From 2ad297344d3239b6bd75e73d68c2d15733bd8f97 Mon Sep 17 00:00:00 2001
From: Richard Belleville <rbellevi@google.com>
Date: Thu, 22 Feb 2024 16:53:49 -0800
Subject: [PATCH 01/16] [Documentation] Make Bazel requirements installable
 directly via pip (#35973)

This fixes the documentation generation tooling.

Closes #35973

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35973 from gnossen:requirements_bazel_fix 1e78fab0084ac09984e0def8cb8245cd9a00ee85
PiperOrigin-RevId: 609544722
---
 requirements.bazel.txt | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/requirements.bazel.txt b/requirements.bazel.txt
index 2ef85776d14..f46432cc888 100644
--- a/requirements.bazel.txt
+++ b/requirements.bazel.txt
@@ -3,7 +3,6 @@ coverage==4.5.4
 cython==0.29.21
 protobuf>=3.5.0.post1, < 4.0dev
 wheel==0.38.1
-google-auth==1.24.0
 oauth2client==4.1.0
 requests==2.25.1
 urllib3==1.26.18
@@ -13,12 +12,11 @@ idna==2.7
 gevent==22.08.0
 zope.event==4.5.0
 setuptools==44.1.1
-xds-protos==0.0.11
 absl-py==1.4.0
 google-cloud-trace==1.11.3
 opencensus-context==0.1.3
 google-cloud-monitoring==2.16.0
-google-api-core==2.14.0
+google-api-core==1.34.1
 proto-plus==1.22.3
 google-auth==2.23.4
 googleapis-common-protos==1.61.0
@@ -30,9 +28,9 @@ greenlet==1.1.3.post0
 zope.interface==6.1
 opentelemetry-sdk==1.21.0
 opentelemetry-api==1.21.0
-importlib-metadata==7.0.1
+importlib-metadata==6.11.0
 Deprecated==1.2.14
-opentelemetry-semantic-conventions==0.43b0
+opentelemetry-semantic-conventions==0.42b0
 typing-extensions==4.9.0
 pyasn1-modules==0.3.0
 zipp==3.17.0

From 3d32d7a15df6c496d914d1408763e66e745cc514 Mon Sep 17 00:00:00 2001
From: Craig Tiller <ctiller@google.com>
Date: Thu, 22 Feb 2024 20:08:48 -0800
Subject: [PATCH 02/16] [chaotic-good] Extend connection timeouts (#35937)

5 seconds is really too small when we've got dozens of connections being established on a busy system. We need a deadline, but it can be significantly looser.

Closes #35937

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35937 from ctiller:timeout1 dc26a82985840155260eb4307053198a0f379d9d
PiperOrigin-RevId: 609587934
---
 .../ext/transport/chaotic_good/client/chaotic_good_connector.cc | 2 +-
 .../ext/transport/chaotic_good/server/chaotic_good_server.cc    | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/core/ext/transport/chaotic_good/client/chaotic_good_connector.cc b/src/core/ext/transport/chaotic_good/client/chaotic_good_connector.cc
index 856e3e56740..d7c438b1311 100644
--- a/src/core/ext/transport/chaotic_good/client/chaotic_good_connector.cc
+++ b/src/core/ext/transport/chaotic_good/client/chaotic_good_connector.cc
@@ -67,7 +67,7 @@ namespace chaotic_good {
 using grpc_event_engine::experimental::EventEngine;
 namespace {
 const int32_t kDataAlignmentBytes = 64;
-const int32_t kTimeoutSecs = 5;
+const int32_t kTimeoutSecs = 120;
 }  // namespace
 
 ChaoticGoodConnector::ChaoticGoodConnector(
diff --git a/src/core/ext/transport/chaotic_good/server/chaotic_good_server.cc b/src/core/ext/transport/chaotic_good/server/chaotic_good_server.cc
index 4359d5648ad..c7815f8b9a2 100644
--- a/src/core/ext/transport/chaotic_good/server/chaotic_good_server.cc
+++ b/src/core/ext/transport/chaotic_good/server/chaotic_good_server.cc
@@ -70,7 +70,7 @@ namespace grpc_core {
 namespace chaotic_good {
 
 namespace {
-const Duration kConnectionDeadline = Duration::Seconds(5);
+const Duration kConnectionDeadline = Duration::Seconds(120);
 }  // namespace
 
 using grpc_event_engine::experimental::EventEngine;

From 1ad14040efa69c5da638a39f9e715826e021faa5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Svensson?= <bjorn.a.svensson@est.tech>
Date: Fri, 23 Feb 2024 10:36:24 -0800
Subject: [PATCH 03/16] [EventEngine] Set DSCP on listener socket (#35983)

Prepare the listener socket with the configured DSCP value to mark outgoing packets correctly.
This is already done correctly for clients.

During implementation and delivery of the DSCP feature both experiments `event_engine_listener` and `event_engine_client` were default `OFF`. Unfortunately the `event_engine_listener` experiment was not enabled correctly during verification, which resulted in that the working `iomgr` codepath was used instead.
This PR adds the missing action which I now have verified correctly.

Fixes #35954

Closes #35983

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35983 from Nordix:fix-dscp 72969db88e701a30f7bc405eb2f3c1c653fd178f
PiperOrigin-RevId: 609770886
---
 .../lib/event_engine/posix_engine/posix_engine_listener_utils.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/core/lib/event_engine/posix_engine/posix_engine_listener_utils.cc b/src/core/lib/event_engine/posix_engine/posix_engine_listener_utils.cc
index 6f4bfe104e9..c5052d38180 100644
--- a/src/core/lib/event_engine/posix_engine/posix_engine_listener_utils.cc
+++ b/src/core/lib/event_engine/posix_engine/posix_engine_listener_utils.cc
@@ -169,6 +169,7 @@ absl::Status PrepareSocket(const PosixTcpOptions& options,
       !ResolvedAddressIsVSock(socket.addr)) {
     GRPC_RETURN_IF_ERROR(socket.sock.SetSocketLowLatency(1));
     GRPC_RETURN_IF_ERROR(socket.sock.SetSocketReuseAddr(1));
+    GRPC_RETURN_IF_ERROR(socket.sock.SetSocketDscp(options.dscp));
     socket.sock.TrySetSocketTcpUserTimeout(options, false);
   }
   GRPC_RETURN_IF_ERROR(socket.sock.SetSocketNoSigpipeIfPossible());

From 6c29a8720e6220c42ffcca2cb6d12de5469de075 Mon Sep 17 00:00:00 2001
From: AJ Heller <hork@google.com>
Date: Fri, 23 Feb 2024 12:10:47 -0800
Subject: [PATCH 04/16] [test] Remove passthru_endpiont and its microbenchmarks
 (#35986)

Closes #35986

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35986 from drfloob:rm-passthru-endpoint 12c491f7f6ffd474fdf6af9cdee6ca1dd012aca4
PiperOrigin-RevId: 609800868
---
 CMakeLists.txt                                |  74 ---
 build_autogenerated.yaml                      | 148 -----
 grpc.gyp                                      |   2 -
 test/core/util/BUILD                          |   2 -
 test/core/util/passthru_endpoint.cc           | 525 ------------------
 test/core/util/passthru_endpoint.h            |  58 --
 .../bm_fullstack_streaming_ping_pong.cc       |  18 -
 .../bm_fullstack_streaming_pump.cc            |   6 -
 .../bm_fullstack_unary_ping_pong.cc           |  55 --
 test/cpp/microbenchmarks/fullstack_fixtures.h |  41 --
 10 files changed, 929 deletions(-)
 delete mode 100644 test/core/util/passthru_endpoint.cc
 delete mode 100644 test/core/util/passthru_endpoint.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index a2a098e5755..fb3dc1cb780 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3940,7 +3940,6 @@ add_library(benchmark_helpers ${_gRPC_STATIC_WIN32}
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -4713,7 +4712,6 @@ add_library(grpc++_test_util
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -5689,7 +5687,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -5851,7 +5848,6 @@ add_executable(test_core_iomgr_timer_list_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -5993,7 +5989,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -6116,7 +6111,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -6661,7 +6655,6 @@ add_executable(alts_security_connector_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -7037,7 +7030,6 @@ add_executable(auth_context_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -7132,7 +7124,6 @@ add_executable(authorization_matchers_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -7272,7 +7263,6 @@ add_executable(aws_request_signer_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -7576,7 +7566,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -7633,7 +7622,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -8247,7 +8235,6 @@ add_executable(buffer_list_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -9304,7 +9291,6 @@ add_executable(cel_authorization_engine_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -9679,7 +9665,6 @@ add_executable(channel_creds_registry_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -10012,7 +9997,6 @@ add_executable(check_gcp_environment_linux_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -10064,7 +10048,6 @@ add_executable(check_gcp_environment_windows_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -10864,7 +10847,6 @@ add_executable(cmdline_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -11005,7 +10987,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -11375,7 +11356,6 @@ add_executable(connectivity_state_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -12770,7 +12750,6 @@ add_executable(endpoint_pair_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -12921,7 +12900,6 @@ add_executable(error_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -12973,7 +12951,6 @@ add_executable(error_utils_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -13025,7 +13002,6 @@ add_executable(evaluate_args_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -13667,7 +13643,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -14387,7 +14362,6 @@ add_executable(format_request_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -14890,7 +14864,6 @@ add_executable(grpc_alts_credentials_options_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -14985,7 +14958,6 @@ add_executable(grpc_authorization_engine_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -15037,7 +15009,6 @@ add_executable(grpc_authorization_policy_provider_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -15425,7 +15396,6 @@ add_executable(grpc_ipv6_loopback_available_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -15667,7 +15637,6 @@ add_executable(grpc_tls_certificate_distributor_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -15719,7 +15688,6 @@ add_executable(grpc_tls_certificate_provider_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -15771,7 +15739,6 @@ add_executable(grpc_tls_certificate_verifier_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -15823,7 +15790,6 @@ add_executable(grpc_tls_credentials_options_comparator_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -15875,7 +15841,6 @@ add_executable(grpc_tls_credentials_options_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -16610,7 +16575,6 @@ add_executable(histogram_test
   test/core/util/histogram_test.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -16704,7 +16668,6 @@ add_executable(hpack_encoder_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -16756,7 +16719,6 @@ add_executable(hpack_parser_table_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -16808,7 +16770,6 @@ add_executable(hpack_parser_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -17528,7 +17489,6 @@ add_executable(insecure_security_connector_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -18193,7 +18153,6 @@ add_executable(json_token_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -18245,7 +18204,6 @@ add_executable(jwt_verifier_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -18980,7 +18938,6 @@ add_executable(matchers_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -19468,7 +19425,6 @@ add_executable(message_compress_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -19562,7 +19518,6 @@ add_executable(metadata_map_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -20867,7 +20822,6 @@ add_executable(parser_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -21190,7 +21144,6 @@ add_executable(ping_abuse_policy_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -21284,7 +21237,6 @@ add_executable(ping_configuration_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -21398,7 +21350,6 @@ add_executable(ping_rate_policy_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -22882,7 +22833,6 @@ add_executable(rbac_translator_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -23250,7 +23200,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -23304,7 +23253,6 @@ add_executable(resolve_address_using_ares_resolver_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -23358,7 +23306,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -23412,7 +23359,6 @@ add_executable(resolve_address_using_native_resolver_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -26117,7 +26063,6 @@ add_executable(secure_endpoint_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -26169,7 +26114,6 @@ add_executable(security_connector_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -26388,7 +26332,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -26460,7 +26403,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -26927,7 +26869,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -27238,7 +27179,6 @@ add_executable(settings_timeout_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -27964,7 +27904,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -28351,7 +28290,6 @@ add_executable(status_conversion_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -28699,7 +28637,6 @@ add_executable(streams_not_seen_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -28922,7 +28859,6 @@ add_executable(system_roots_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -29009,7 +28945,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -29108,7 +29043,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -29162,7 +29096,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -29599,7 +29532,6 @@ add_executable(test_core_iomgr_timer_heap_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -29651,7 +29583,6 @@ add_executable(test_core_security_credentials_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -29703,7 +29634,6 @@ add_executable(test_core_security_ssl_credentials_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -30630,7 +30560,6 @@ add_executable(timeout_encoding_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -30932,7 +30861,6 @@ add_executable(tls_security_connector_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
@@ -32497,7 +32425,6 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     test/core/util/histogram.cc
     test/core/util/mock_endpoint.cc
     test/core/util/parse_hexstring.cc
-    test/core/util/passthru_endpoint.cc
     test/core/util/resolve_localhost_ip46.cc
     test/core/util/slice_splitter.cc
     test/core/util/tracer_util.cc
@@ -33595,7 +33522,6 @@ add_executable(xds_credentials_test
   test/core/util/histogram.cc
   test/core/util/mock_endpoint.cc
   test/core/util/parse_hexstring.cc
-  test/core/util/passthru_endpoint.cc
   test/core/util/resolve_localhost_ip46.cc
   test/core/util/slice_splitter.cc
   test/core/util/tracer_util.cc
diff --git a/build_autogenerated.yaml b/build_autogenerated.yaml
index 9047e2c274f..ea4c8a834f7 100644
--- a/build_autogenerated.yaml
+++ b/build_autogenerated.yaml
@@ -3578,7 +3578,6 @@ libs:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -3596,7 +3595,6 @@ libs:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -4001,7 +3999,6 @@ libs:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -4023,7 +4020,6 @@ libs:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -5096,7 +5092,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -5108,7 +5103,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -5169,7 +5163,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -5181,7 +5174,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -5259,7 +5251,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -5275,7 +5266,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -5324,7 +5314,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -5335,7 +5324,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -5517,7 +5505,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -5529,7 +5516,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -5635,7 +5621,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -5647,7 +5632,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -5679,7 +5663,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -5691,7 +5674,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -5740,7 +5722,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -5752,7 +5733,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -5887,7 +5867,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -5902,7 +5881,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -5928,7 +5906,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -5943,7 +5920,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -6250,7 +6226,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -6262,7 +6237,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -7257,7 +7231,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -7358,7 +7331,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -7477,7 +7449,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -7489,7 +7460,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -7586,7 +7556,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -7598,7 +7567,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -7618,7 +7586,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -7630,7 +7597,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -8032,7 +7998,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -8044,7 +8009,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -8090,7 +8054,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -8102,7 +8065,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -8257,7 +8219,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -8269,7 +8230,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -8942,7 +8902,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -8955,7 +8914,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -9001,7 +8959,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -9014,7 +8971,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -9035,7 +8991,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -9047,7 +9002,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -9067,7 +9021,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -9079,7 +9032,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -9435,7 +9387,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -9447,7 +9398,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -10064,7 +10014,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -10080,7 +10029,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -10294,7 +10242,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -10306,7 +10253,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -10337,7 +10283,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -10350,7 +10295,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -10370,7 +10314,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -10382,7 +10325,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -10546,7 +10488,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -10558,7 +10499,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -10618,7 +10558,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -10630,7 +10569,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -10650,7 +10588,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -10662,7 +10599,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -10682,7 +10618,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -10694,7 +10629,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -10714,7 +10648,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -10726,7 +10659,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -10746,7 +10678,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -10758,7 +10689,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -11055,7 +10985,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -11067,7 +10996,6 @@ targets:
   - test/core/util/histogram_test.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -11099,7 +11027,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -11111,7 +11038,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -11132,7 +11058,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -11144,7 +11069,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -11165,7 +11089,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -11177,7 +11100,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -11501,7 +11423,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -11513,7 +11434,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -11899,7 +11819,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -11911,7 +11830,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -11932,7 +11850,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -11944,7 +11861,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -12405,7 +12321,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -12417,7 +12332,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -12735,7 +12649,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -12747,7 +12660,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -12778,7 +12690,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -12790,7 +12701,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -13341,7 +13251,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -13357,7 +13266,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -13575,7 +13483,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -13587,7 +13494,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -13620,7 +13526,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -13632,7 +13537,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -13714,7 +13618,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -13726,7 +13629,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -14368,7 +14270,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -14380,7 +14281,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -14618,7 +14518,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -14630,7 +14529,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -14657,7 +14555,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -14670,7 +14567,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -14691,7 +14587,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -14703,7 +14598,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -14730,7 +14624,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -14743,7 +14636,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -17040,7 +16932,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -17053,7 +16944,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -17073,7 +16963,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -17085,7 +16974,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -17155,7 +17043,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -17170,7 +17057,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -17196,7 +17082,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -17211,7 +17096,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -17386,7 +17270,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -17401,7 +17284,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -17541,7 +17423,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -17553,7 +17434,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -17984,7 +17864,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -17996,7 +17875,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -18124,7 +18002,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -18136,7 +18013,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -18284,7 +18160,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -18297,7 +18172,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -18369,7 +18243,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -18381,7 +18254,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -18416,7 +18288,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -18428,7 +18299,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -18468,7 +18338,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -18481,7 +18350,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -18504,7 +18372,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -18516,7 +18383,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -18727,7 +18593,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -18739,7 +18604,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -18760,7 +18624,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -18772,7 +18635,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -18792,7 +18654,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -18804,7 +18665,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -19178,7 +19038,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -19190,7 +19049,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -19277,7 +19135,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -19289,7 +19146,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -20161,7 +20017,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -20179,7 +20034,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
@@ -20546,7 +20400,6 @@ targets:
   - test/core/util/mock_authorization_endpoint.h
   - test/core/util/mock_endpoint.h
   - test/core/util/parse_hexstring.h
-  - test/core/util/passthru_endpoint.h
   - test/core/util/resolve_localhost_ip46.h
   - test/core/util/slice_splitter.h
   - test/core/util/tracer_util.h
@@ -20558,7 +20411,6 @@ targets:
   - test/core/util/histogram.cc
   - test/core/util/mock_endpoint.cc
   - test/core/util/parse_hexstring.cc
-  - test/core/util/passthru_endpoint.cc
   - test/core/util/resolve_localhost_ip46.cc
   - test/core/util/slice_splitter.cc
   - test/core/util/tracer_util.cc
diff --git a/grpc.gyp b/grpc.gyp
index 6448b135e88..0e655558818 100644
--- a/grpc.gyp
+++ b/grpc.gyp
@@ -1794,7 +1794,6 @@
         'test/core/util/histogram.cc',
         'test/core/util/mock_endpoint.cc',
         'test/core/util/parse_hexstring.cc',
-        'test/core/util/passthru_endpoint.cc',
         'test/core/util/resolve_localhost_ip46.cc',
         'test/core/util/slice_splitter.cc',
         'test/core/util/tracer_util.cc',
@@ -1952,7 +1951,6 @@
         'test/core/util/histogram.cc',
         'test/core/util/mock_endpoint.cc',
         'test/core/util/parse_hexstring.cc',
-        'test/core/util/passthru_endpoint.cc',
         'test/core/util/resolve_localhost_ip46.cc',
         'test/core/util/slice_splitter.cc',
         'test/core/util/tracer_util.cc',
diff --git a/test/core/util/BUILD b/test/core/util/BUILD
index 2de9ece5fff..d8ace2ee84e 100644
--- a/test/core/util/BUILD
+++ b/test/core/util/BUILD
@@ -63,7 +63,6 @@ grpc_cc_library(
         "histogram.cc",
         "mock_endpoint.cc",
         "parse_hexstring.cc",
-        "passthru_endpoint.cc",
         "resolve_localhost_ip46.cc",
         "slice_splitter.cc",
         "tracer_util.cc",
@@ -77,7 +76,6 @@ grpc_cc_library(
         "mock_authorization_endpoint.h",
         "mock_endpoint.h",
         "parse_hexstring.h",
-        "passthru_endpoint.h",
         "resolve_localhost_ip46.h",
         "slice_splitter.h",
         "tracer_util.h",
diff --git a/test/core/util/passthru_endpoint.cc b/test/core/util/passthru_endpoint.cc
deleted file mode 100644
index cc37aabd278..00000000000
--- a/test/core/util/passthru_endpoint.cc
+++ /dev/null
@@ -1,525 +0,0 @@
-//
-//
-// Copyright 2016 gRPC authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-//
-
-#include "test/core/util/passthru_endpoint.h"
-
-#include <string.h>
-
-#include <algorithm>
-#include <functional>
-#include <memory>
-#include <string>
-
-#include "absl/status/status.h"
-#include "absl/strings/str_format.h"
-#include "absl/strings/string_view.h"
-#include "absl/types/optional.h"
-
-#include <grpc/event_engine/event_engine.h>
-#include <grpc/slice.h>
-#include <grpc/slice_buffer.h>
-#include <grpc/support/alloc.h>
-#include <grpc/support/log.h>
-
-#include "src/core/lib/event_engine/default_event_engine.h"
-#include "src/core/lib/gprpp/debug_location.h"
-#include "src/core/lib/gprpp/time.h"
-#include "src/core/lib/iomgr/closure.h"
-#include "src/core/lib/iomgr/error.h"
-#include "src/core/lib/iomgr/exec_ctx.h"
-#include "src/core/lib/iomgr/iomgr_fwd.h"
-
-using ::grpc_event_engine::experimental::EventEngine;
-using ::grpc_event_engine::experimental::GetDefaultEventEngine;
-
-typedef struct passthru_endpoint passthru_endpoint;
-
-typedef struct {
-  bool is_armed;
-  grpc_endpoint* ep;
-  grpc_slice_buffer* slices;
-  grpc_closure* cb;
-} pending_op;
-
-typedef struct {
-  absl::optional<EventEngine::TaskHandle> timer_handle;
-  uint64_t allowed_write_bytes;
-  uint64_t allowed_read_bytes;
-  std::vector<grpc_passthru_endpoint_channel_action> actions;
-  std::function<void()> on_complete;
-} grpc_passthru_endpoint_channel_effects;
-
-typedef struct {
-  grpc_endpoint base;
-  passthru_endpoint* parent;
-  grpc_slice_buffer read_buffer;
-  grpc_slice_buffer write_buffer;
-  grpc_slice_buffer* on_read_out;
-  grpc_closure* on_read;
-  pending_op pending_read_op;
-  pending_op pending_write_op;
-  uint64_t bytes_read_so_far;
-  uint64_t bytes_written_so_far;
-} half;
-
-struct passthru_endpoint {
-  gpr_mu mu;
-  int halves;
-  grpc_passthru_endpoint_stats* stats;
-  grpc_passthru_endpoint_channel_effects* channel_effects;
-  bool simulate_channel_actions;
-  bool shutdown;
-  half client;
-  half server;
-};
-
-static void do_pending_read_op_locked(half* m, grpc_error_handle error) {
-  GPR_ASSERT(m->pending_read_op.is_armed);
-  GPR_ASSERT(m->bytes_read_so_far <=
-             m->parent->channel_effects->allowed_read_bytes);
-  if (m->parent->shutdown) {
-    grpc_core::ExecCtx::Run(DEBUG_LOCATION, m->pending_read_op.cb,
-                            GRPC_ERROR_CREATE("Already shutdown"));
-    // Move any pending data into pending_read_op.slices so that it may be
-    // free'ed by the executing callback.
-    grpc_slice_buffer_move_into(&m->read_buffer, m->pending_read_op.slices);
-    m->pending_read_op.is_armed = false;
-    return;
-  }
-
-  if (m->bytes_read_so_far == m->parent->channel_effects->allowed_read_bytes) {
-    // Keep it in pending state.
-    return;
-  }
-  // This delayed processing should only be invoked when read_buffer has
-  // something in it.
-  GPR_ASSERT(m->read_buffer.count > 0);
-  uint64_t readable_length = std::min<uint64_t>(
-      m->read_buffer.length,
-      m->parent->channel_effects->allowed_read_bytes - m->bytes_read_so_far);
-  GPR_ASSERT(readable_length > 0);
-  grpc_slice_buffer_move_first(&m->read_buffer, readable_length,
-                               m->pending_read_op.slices);
-  grpc_core::ExecCtx::Run(DEBUG_LOCATION, m->pending_read_op.cb, error);
-  if (m->parent->simulate_channel_actions) {
-    m->bytes_read_so_far += readable_length;
-  }
-  m->pending_read_op.is_armed = false;
-}
-
-static void me_read(grpc_endpoint* ep, grpc_slice_buffer* slices,
-                    grpc_closure* cb, bool /*urgent*/,
-                    int /*min_progress_size*/) {
-  half* m = reinterpret_cast<half*>(ep);
-  gpr_mu_lock(&m->parent->mu);
-  if (m->parent->shutdown) {
-    grpc_core::ExecCtx::Run(DEBUG_LOCATION, cb,
-                            GRPC_ERROR_CREATE("Already shutdown"));
-  } else if (m->read_buffer.count > 0) {
-    GPR_ASSERT(!m->pending_read_op.is_armed);
-    GPR_ASSERT(!m->on_read);
-    m->pending_read_op.is_armed = true;
-    m->pending_read_op.cb = cb;
-    m->pending_read_op.ep = ep;
-    m->pending_read_op.slices = slices;
-    do_pending_read_op_locked(m, absl::OkStatus());
-  } else {
-    GPR_ASSERT(!m->pending_read_op.is_armed);
-    m->on_read = cb;
-    m->on_read_out = slices;
-  }
-  gpr_mu_unlock(&m->parent->mu);
-}
-
-// Copy src slice and split the copy at n bytes into two separate slices
-void grpc_slice_copy_split(grpc_slice src, uint64_t n, grpc_slice& split1,
-                           grpc_slice& split2) {
-  GPR_ASSERT(n <= GRPC_SLICE_LENGTH(src));
-  if (n == GRPC_SLICE_LENGTH(src)) {
-    split1 = grpc_slice_copy(src);
-    split2 = grpc_empty_slice();
-    return;
-  }
-  split1 = GRPC_SLICE_MALLOC(n);
-  memcpy(GRPC_SLICE_START_PTR(split1), GRPC_SLICE_START_PTR(src), n);
-  split2 = GRPC_SLICE_MALLOC(GRPC_SLICE_LENGTH(src) - n);
-  memcpy(GRPC_SLICE_START_PTR(split2), GRPC_SLICE_START_PTR(src) + n,
-         GRPC_SLICE_LENGTH(src) - n);
-}
-
-static half* other_half(half* h) {
-  if (h == &h->parent->client) return &h->parent->server;
-  return &h->parent->client;
-}
-
-static void do_pending_write_op_locked(half* m, grpc_error_handle error) {
-  GPR_ASSERT(m->pending_write_op.is_armed);
-  GPR_ASSERT(m->bytes_written_so_far <=
-             m->parent->channel_effects->allowed_write_bytes);
-  if (m->parent->shutdown) {
-    grpc_core::ExecCtx::Run(DEBUG_LOCATION, m->pending_write_op.cb,
-                            GRPC_ERROR_CREATE("Already shutdown"));
-    m->pending_write_op.is_armed = false;
-    grpc_slice_buffer_reset_and_unref(m->pending_write_op.slices);
-    return;
-  }
-  if (m->bytes_written_so_far ==
-      m->parent->channel_effects->allowed_write_bytes) {
-    // Keep it in pending state.
-    return;
-  }
-
-  half* other = other_half(m);
-  uint64_t max_writable =
-      std::min<uint64_t>(m->pending_write_op.slices->length,
-                         m->parent->channel_effects->allowed_write_bytes -
-                             m->bytes_written_so_far);
-  uint64_t max_readable = other->parent->channel_effects->allowed_read_bytes -
-                          other->bytes_read_so_far;
-  uint64_t immediate_bytes_read =
-      other->on_read != nullptr ? std::min<uint64_t>(max_readable, max_writable)
-                                : 0;
-
-  GPR_ASSERT(max_writable > 0);
-  GPR_ASSERT(max_readable >= 0);
-  // At the end of this process, we should have written max_writable bytes;
-  if (m->parent->simulate_channel_actions) {
-    m->bytes_written_so_far += max_writable;
-  }
-  // Estimate if the original write would still be pending at the end of this
-  // process
-  bool would_write_be_pending =
-      max_writable < m->pending_write_op.slices->length;
-  if (!m->parent->simulate_channel_actions) {
-    GPR_ASSERT(!would_write_be_pending);
-  }
-  grpc_slice_buffer* slices = m->pending_write_op.slices;
-  grpc_slice_buffer* dest =
-      other->on_read != nullptr ? other->on_read_out : &other->read_buffer;
-  while (max_writable > 0) {
-    grpc_slice slice = grpc_slice_buffer_take_first(slices);
-    uint64_t slice_length = GRPC_SLICE_LENGTH(slice);
-    GPR_ASSERT(slice_length > 0);
-    grpc_slice split1, split2;
-    uint64_t split_length = 0;
-    if (slice_length <= max_readable) {
-      split_length = std::min<uint64_t>(slice_length, max_writable);
-    } else if (max_readable > 0) {
-      // slice_length > max_readable
-      split_length = std::min<uint64_t>(max_readable, max_writable);
-    } else {
-      // slice_length still > max_readable but max_readable is 0.
-      // In this case put the bytes into other->read_buffer. During a future
-      // read if max_readable still remains zero at the time of read, the
-      // pending read logic will kick in.
-      dest = &other->read_buffer;
-      split_length = std::min<uint64_t>(slice_length, max_writable);
-    }
-
-    grpc_slice_copy_split(slice, split_length, split1, split2);
-    grpc_slice_unref(slice);
-    // Write a copy of the slice to the destination to be read
-    grpc_slice_buffer_add_indexed(dest, split1);
-    // Re-insert split2 into source for next iteration.
-    if (GRPC_SLICE_LENGTH(split2) > 0) {
-      grpc_slice_buffer_undo_take_first(slices, split2);
-    } else {
-      grpc_slice_unref(split2);
-    }
-
-    if (max_readable > 0) {
-      GPR_ASSERT(max_readable >= static_cast<uint64_t>(split_length));
-      max_readable -= split_length;
-    }
-
-    GPR_ASSERT(max_writable >= static_cast<uint64_t>(split_length));
-    max_writable -= split_length;
-  }
-
-  if (immediate_bytes_read > 0) {
-    GPR_ASSERT(!other->pending_read_op.is_armed);
-    if (m->parent->simulate_channel_actions) {
-      other->bytes_read_so_far += immediate_bytes_read;
-    }
-    grpc_core::ExecCtx::Run(DEBUG_LOCATION, other->on_read, error);
-    other->on_read = nullptr;
-  }
-
-  if (!would_write_be_pending) {
-    // No slices should be left
-    GPR_ASSERT(m->pending_write_op.slices->count == 0);
-    grpc_slice_buffer_reset_and_unref(m->pending_write_op.slices);
-    m->pending_write_op.is_armed = false;
-    grpc_core::ExecCtx::Run(DEBUG_LOCATION, m->pending_write_op.cb, error);
-  }
-}
-
-static void me_write(grpc_endpoint* ep, grpc_slice_buffer* slices,
-                     grpc_closure* cb, void* /*arg*/, int /*max_frame_size*/) {
-  half* m = reinterpret_cast<half*>(ep);
-  gpr_mu_lock(&m->parent->mu);
-  gpr_atm_full_fetch_add(&m->parent->stats->num_writes, (gpr_atm)1);
-  if (m->parent->shutdown) {
-    grpc_core::ExecCtx::Run(DEBUG_LOCATION, cb,
-                            GRPC_ERROR_CREATE("Endpoint already shutdown"));
-  } else {
-    GPR_ASSERT(!m->pending_write_op.is_armed);
-    // Copy slices into m->pending_write_op.slices
-    m->pending_write_op.slices = &m->write_buffer;
-    GPR_ASSERT(m->pending_write_op.slices->count == 0);
-    for (int i = 0; i < static_cast<int>(slices->count); i++) {
-      if (GRPC_SLICE_LENGTH(slices->slices[i]) > 0) {
-        grpc_slice_buffer_add_indexed(m->pending_write_op.slices,
-                                      grpc_slice_copy(slices->slices[i]));
-      }
-    }
-    if (m->pending_write_op.slices->count > 0) {
-      m->pending_write_op.is_armed = true;
-      m->pending_write_op.cb = cb;
-      m->pending_write_op.ep = ep;
-      do_pending_write_op_locked(m, absl::OkStatus());
-    } else {
-      // There is nothing to write. Schedule callback to be run right away.
-      grpc_core::ExecCtx::Run(DEBUG_LOCATION, cb, absl::OkStatus());
-    }
-  }
-  gpr_mu_unlock(&m->parent->mu);
-}
-
-void flush_pending_ops_locked(half* m, grpc_error_handle error) {
-  if (m->pending_read_op.is_armed) {
-    do_pending_read_op_locked(m, error);
-  }
-  if (m->pending_write_op.is_armed) {
-    do_pending_write_op_locked(m, error);
-  }
-}
-
-static void me_add_to_pollset(grpc_endpoint* /*ep*/,
-                              grpc_pollset* /*pollset*/) {}
-
-static void me_add_to_pollset_set(grpc_endpoint* /*ep*/,
-                                  grpc_pollset_set* /*pollset*/) {}
-
-static void me_delete_from_pollset_set(grpc_endpoint* /*ep*/,
-                                       grpc_pollset_set* /*pollset*/) {}
-
-static void shutdown_locked(half* m, grpc_error_handle why) {
-  m->parent->shutdown = true;
-  flush_pending_ops_locked(m, absl::OkStatus());
-  if (m->on_read) {
-    grpc_core::ExecCtx::Run(DEBUG_LOCATION, m->on_read,
-                            GRPC_ERROR_CREATE_REFERENCING("Shutdown", &why, 1));
-    m->on_read = nullptr;
-  }
-  m = other_half(m);
-  flush_pending_ops_locked(m, absl::OkStatus());
-  if (m->on_read) {
-    grpc_core::ExecCtx::Run(DEBUG_LOCATION, m->on_read,
-                            GRPC_ERROR_CREATE_REFERENCING("Shutdown", &why, 1));
-    m->on_read = nullptr;
-  }
-}
-
-static void me_shutdown(grpc_endpoint* ep, grpc_error_handle why) {
-  half* m = reinterpret_cast<half*>(ep);
-  gpr_mu_lock(&m->parent->mu);
-  shutdown_locked(m, why);
-  gpr_mu_unlock(&m->parent->mu);
-}
-
-void grpc_passthru_endpoint_destroy(passthru_endpoint* p) {
-  gpr_mu_destroy(&p->mu);
-  grpc_passthru_endpoint_stats_destroy(p->stats);
-  delete p->channel_effects;
-  grpc_slice_buffer_destroy(&p->client.read_buffer);
-  grpc_slice_buffer_destroy(&p->server.read_buffer);
-  grpc_slice_buffer_destroy(&p->client.write_buffer);
-  grpc_slice_buffer_destroy(&p->server.write_buffer);
-  gpr_free(p);
-}
-
-static void do_next_sched_channel_action(void* arg, grpc_error_handle error);
-
-static void me_destroy(grpc_endpoint* ep) {
-  passthru_endpoint* p = (reinterpret_cast<half*>(ep))->parent;
-  gpr_mu_lock(&p->mu);
-  if (0 == --p->halves && p->channel_effects->actions.empty()) {
-    // no pending channel actions exist
-    gpr_mu_unlock(&p->mu);
-    grpc_passthru_endpoint_destroy(p);
-  } else {
-    if (p->halves == 0 && p->simulate_channel_actions) {
-      if (p->channel_effects->timer_handle.has_value()) {
-        if (GetDefaultEventEngine()->Cancel(
-                *p->channel_effects->timer_handle)) {
-          gpr_mu_unlock(&p->mu);
-          // This will destroy the passthru endpoint so just return after that.
-          do_next_sched_channel_action(ep, absl::CancelledError());
-          return;
-        }
-        p->channel_effects->timer_handle.reset();
-      }
-    }
-    gpr_mu_unlock(&p->mu);
-  }
-}
-
-static absl::string_view me_get_peer(grpc_endpoint* ep) {
-  passthru_endpoint* p = (reinterpret_cast<half*>(ep))->parent;
-  return (reinterpret_cast<half*>(ep)) == &p->client
-             ? "fake:mock_client_endpoint"
-             : "fake:mock_server_endpoint";
-}
-
-static absl::string_view me_get_local_address(grpc_endpoint* ep) {
-  passthru_endpoint* p = (reinterpret_cast<half*>(ep))->parent;
-  return (reinterpret_cast<half*>(ep)) == &p->client
-             ? "fake:mock_client_endpoint"
-             : "fake:mock_server_endpoint";
-}
-
-static int me_get_fd(grpc_endpoint* /*ep*/) { return -1; }
-
-static bool me_can_track_err(grpc_endpoint* /*ep*/) { return false; }
-
-static const grpc_endpoint_vtable vtable = {
-    me_read,
-    me_write,
-    me_add_to_pollset,
-    me_add_to_pollset_set,
-    me_delete_from_pollset_set,
-    me_shutdown,
-    me_destroy,
-    me_get_peer,
-    me_get_local_address,
-    me_get_fd,
-    me_can_track_err,
-};
-
-static void half_init(half* m, passthru_endpoint* parent,
-                      const char* half_name) {
-  m->base.vtable = &vtable;
-  m->parent = parent;
-  grpc_slice_buffer_init(&m->read_buffer);
-  grpc_slice_buffer_init(&m->write_buffer);
-  m->pending_write_op.slices = nullptr;
-  m->on_read = nullptr;
-  m->bytes_read_so_far = 0;
-  m->bytes_written_so_far = 0;
-  m->pending_write_op.is_armed = false;
-  m->pending_read_op.is_armed = false;
-  std::string name =
-      absl::StrFormat("passthru_endpoint_%s_%p", half_name, parent);
-}
-
-void grpc_passthru_endpoint_create(grpc_endpoint** client,
-                                   grpc_endpoint** server,
-                                   grpc_passthru_endpoint_stats* stats,
-                                   bool simulate_channel_actions) {
-  passthru_endpoint* m =
-      static_cast<passthru_endpoint*>(gpr_malloc(sizeof(*m)));
-  m->halves = 2;
-  m->shutdown = false;
-  if (stats == nullptr) {
-    m->stats = grpc_passthru_endpoint_stats_create();
-  } else {
-    gpr_ref(&stats->refs);
-    m->stats = stats;
-  }
-  m->channel_effects = new grpc_passthru_endpoint_channel_effects();
-  m->simulate_channel_actions = simulate_channel_actions;
-  if (!simulate_channel_actions) {
-    m->channel_effects->allowed_read_bytes = UINT64_MAX;
-    m->channel_effects->allowed_write_bytes = UINT64_MAX;
-  }
-  half_init(&m->client, m, "client");
-  half_init(&m->server, m, "server");
-  gpr_mu_init(&m->mu);
-  *client = &m->client.base;
-  *server = &m->server.base;
-}
-
-grpc_passthru_endpoint_stats* grpc_passthru_endpoint_stats_create() {
-  grpc_passthru_endpoint_stats* stats =
-      static_cast<grpc_passthru_endpoint_stats*>(
-          gpr_malloc(sizeof(grpc_passthru_endpoint_stats)));
-  memset(stats, 0, sizeof(*stats));
-  gpr_ref_init(&stats->refs, 1);
-  return stats;
-}
-
-void grpc_passthru_endpoint_stats_destroy(grpc_passthru_endpoint_stats* stats) {
-  if (gpr_unref(&stats->refs)) {
-    gpr_free(stats);
-  }
-}
-
-static void sched_next_channel_action_locked(half* m);
-
-static void do_next_sched_channel_action(void* arg, grpc_error_handle error) {
-  half* m = reinterpret_cast<half*>(arg);
-  gpr_mu_lock(&m->parent->mu);
-  GPR_ASSERT(!m->parent->channel_effects->actions.empty());
-  if (m->parent->halves == 0) {
-    gpr_mu_unlock(&m->parent->mu);
-    grpc_passthru_endpoint_destroy(m->parent);
-    return;
-  }
-  auto curr_action = m->parent->channel_effects->actions[0];
-  m->parent->channel_effects->actions.erase(
-      m->parent->channel_effects->actions.begin());
-  m->parent->channel_effects->allowed_read_bytes +=
-      curr_action.add_n_readable_bytes;
-  m->parent->channel_effects->allowed_write_bytes +=
-      curr_action.add_n_writable_bytes;
-  flush_pending_ops_locked(m, error);
-  flush_pending_ops_locked(other_half(m), error);
-  sched_next_channel_action_locked(m);
-  gpr_mu_unlock(&m->parent->mu);
-}
-
-static void sched_next_channel_action_locked(half* m) {
-  if (m->parent->channel_effects->actions.empty()) {
-    grpc_error_handle err = GRPC_ERROR_CREATE("Channel actions complete");
-    shutdown_locked(m, err);
-    return;
-  }
-  m->parent->channel_effects->timer_handle = GetDefaultEventEngine()->RunAfter(
-      grpc_core::Duration::Milliseconds(
-          m->parent->channel_effects->actions[0].wait_ms),
-      [m] {
-        grpc_core::ApplicationCallbackExecCtx callback_exec_ctx;
-        grpc_core::ExecCtx exec_ctx;
-        do_next_sched_channel_action(m, absl::OkStatus());
-      });
-}
-
-void start_scheduling_grpc_passthru_endpoint_channel_effects(
-    grpc_endpoint* ep,
-    const std::vector<grpc_passthru_endpoint_channel_action>& actions) {
-  half* m = reinterpret_cast<half*>(ep);
-  gpr_mu_lock(&m->parent->mu);
-  if (!m->parent->simulate_channel_actions || m->parent->shutdown) {
-    gpr_mu_unlock(&m->parent->mu);
-    return;
-  }
-  m->parent->channel_effects->actions = actions;
-  sched_next_channel_action_locked(m);
-  gpr_mu_unlock(&m->parent->mu);
-}
diff --git a/test/core/util/passthru_endpoint.h b/test/core/util/passthru_endpoint.h
deleted file mode 100644
index 4fc94753e70..00000000000
--- a/test/core/util/passthru_endpoint.h
+++ /dev/null
@@ -1,58 +0,0 @@
-//
-//
-// Copyright 2016 gRPC authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-//
-
-#ifndef GRPC_TEST_CORE_UTIL_PASSTHRU_ENDPOINT_H
-#define GRPC_TEST_CORE_UTIL_PASSTHRU_ENDPOINT_H
-
-#include <stdint.h>
-
-#include <vector>
-
-#include <grpc/support/atm.h>
-#include <grpc/support/sync.h>
-
-#include "src/core/lib/iomgr/endpoint.h"
-
-// The struct is refcounted, always use grpc_passthru_endpoint_stats_create and
-// grpc_passthru_endpoint_stats_destroy, rather then embedding it in your
-// objects by value.
-typedef struct {
-  gpr_refcount refs;
-  gpr_atm num_writes;
-} grpc_passthru_endpoint_stats;
-
-typedef struct {
-  uint64_t wait_ms;
-  uint64_t add_n_writable_bytes;
-  uint64_t add_n_readable_bytes;
-} grpc_passthru_endpoint_channel_action;
-
-void grpc_passthru_endpoint_create(grpc_endpoint** client,
-                                   grpc_endpoint** server,
-                                   grpc_passthru_endpoint_stats* stats,
-                                   bool simulate_channel_actions = false);
-
-grpc_passthru_endpoint_stats* grpc_passthru_endpoint_stats_create();
-
-void grpc_passthru_endpoint_stats_destroy(grpc_passthru_endpoint_stats* stats);
-
-void start_scheduling_grpc_passthru_endpoint_channel_effects(
-    grpc_endpoint* ep,
-    const std::vector<grpc_passthru_endpoint_channel_action>& actions);
-
-#endif  // GRPC_TEST_CORE_UTIL_PASSTHRU_ENDPOINT_H
diff --git a/test/cpp/microbenchmarks/bm_fullstack_streaming_ping_pong.cc b/test/cpp/microbenchmarks/bm_fullstack_streaming_ping_pong.cc
index 06e40752940..38480c6463b 100644
--- a/test/cpp/microbenchmarks/bm_fullstack_streaming_ping_pong.cc
+++ b/test/cpp/microbenchmarks/bm_fullstack_streaming_ping_pong.cc
@@ -52,34 +52,22 @@ static void StreamingPingPongArgs(benchmark::internal::Benchmark* b) {
   }
 }
 
-BENCHMARK_TEMPLATE(BM_StreamingPingPong, InProcessCHTTP2, NoOpMutator,
-                   NoOpMutator)
-    ->Apply(StreamingPingPongArgs);
 BENCHMARK_TEMPLATE(BM_StreamingPingPong, TCP, NoOpMutator, NoOpMutator)
     ->Apply(StreamingPingPongArgs);
 BENCHMARK_TEMPLATE(BM_StreamingPingPong, InProcess, NoOpMutator, NoOpMutator)
     ->Apply(StreamingPingPongArgs);
 
-BENCHMARK_TEMPLATE(BM_StreamingPingPongMsgs, InProcessCHTTP2, NoOpMutator,
-                   NoOpMutator)
-    ->Range(0, kMaxMessageSize);
 BENCHMARK_TEMPLATE(BM_StreamingPingPongMsgs, TCP, NoOpMutator, NoOpMutator)
     ->Range(0, kMaxMessageSize);
 BENCHMARK_TEMPLATE(BM_StreamingPingPongMsgs, InProcess, NoOpMutator,
                    NoOpMutator)
     ->Range(0, kMaxMessageSize);
 
-BENCHMARK_TEMPLATE(BM_StreamingPingPong, MinInProcessCHTTP2, NoOpMutator,
-                   NoOpMutator)
-    ->Apply(StreamingPingPongArgs);
 BENCHMARK_TEMPLATE(BM_StreamingPingPong, MinTCP, NoOpMutator, NoOpMutator)
     ->Apply(StreamingPingPongArgs);
 BENCHMARK_TEMPLATE(BM_StreamingPingPong, MinInProcess, NoOpMutator, NoOpMutator)
     ->Apply(StreamingPingPongArgs);
 
-BENCHMARK_TEMPLATE(BM_StreamingPingPongMsgs, MinInProcessCHTTP2, NoOpMutator,
-                   NoOpMutator)
-    ->Range(0, kMaxMessageSize);
 BENCHMARK_TEMPLATE(BM_StreamingPingPongMsgs, MinTCP, NoOpMutator, NoOpMutator)
     ->Range(0, kMaxMessageSize);
 BENCHMARK_TEMPLATE(BM_StreamingPingPongMsgs, MinInProcess, NoOpMutator,
@@ -106,12 +94,6 @@ static void StreamingPingPongWithCoalescingApiArgs(
   }
 }
 
-BENCHMARK_TEMPLATE(BM_StreamingPingPongWithCoalescingApi, InProcessCHTTP2,
-                   NoOpMutator, NoOpMutator)
-    ->Apply(StreamingPingPongWithCoalescingApiArgs);
-BENCHMARK_TEMPLATE(BM_StreamingPingPongWithCoalescingApi, MinInProcessCHTTP2,
-                   NoOpMutator, NoOpMutator)
-    ->Apply(StreamingPingPongWithCoalescingApiArgs);
 BENCHMARK_TEMPLATE(BM_StreamingPingPongWithCoalescingApi, InProcess,
                    NoOpMutator, NoOpMutator)
     ->Apply(StreamingPingPongWithCoalescingApiArgs);
diff --git a/test/cpp/microbenchmarks/bm_fullstack_streaming_pump.cc b/test/cpp/microbenchmarks/bm_fullstack_streaming_pump.cc
index a4d5a42b7fd..6eae11f4be1 100644
--- a/test/cpp/microbenchmarks/bm_fullstack_streaming_pump.cc
+++ b/test/cpp/microbenchmarks/bm_fullstack_streaming_pump.cc
@@ -35,24 +35,18 @@ BENCHMARK_TEMPLATE(BM_PumpStreamClientToServer, UDS)
     ->Range(0, 128 * 1024 * 1024);
 BENCHMARK_TEMPLATE(BM_PumpStreamClientToServer, InProcess)
     ->Range(0, 128 * 1024 * 1024);
-BENCHMARK_TEMPLATE(BM_PumpStreamClientToServer, InProcessCHTTP2)
-    ->Range(0, 128 * 1024 * 1024);
 BENCHMARK_TEMPLATE(BM_PumpStreamServerToClient, TCP)
     ->Range(0, 128 * 1024 * 1024);
 BENCHMARK_TEMPLATE(BM_PumpStreamServerToClient, UDS)
     ->Range(0, 128 * 1024 * 1024);
 BENCHMARK_TEMPLATE(BM_PumpStreamServerToClient, InProcess)
     ->Range(0, 128 * 1024 * 1024);
-BENCHMARK_TEMPLATE(BM_PumpStreamServerToClient, InProcessCHTTP2)
-    ->Range(0, 128 * 1024 * 1024);
 BENCHMARK_TEMPLATE(BM_PumpStreamClientToServer, MinTCP)->Arg(0);
 BENCHMARK_TEMPLATE(BM_PumpStreamClientToServer, MinUDS)->Arg(0);
 BENCHMARK_TEMPLATE(BM_PumpStreamClientToServer, MinInProcess)->Arg(0);
-BENCHMARK_TEMPLATE(BM_PumpStreamClientToServer, MinInProcessCHTTP2)->Arg(0);
 BENCHMARK_TEMPLATE(BM_PumpStreamServerToClient, MinTCP)->Arg(0);
 BENCHMARK_TEMPLATE(BM_PumpStreamServerToClient, MinUDS)->Arg(0);
 BENCHMARK_TEMPLATE(BM_PumpStreamServerToClient, MinInProcess)->Arg(0);
-BENCHMARK_TEMPLATE(BM_PumpStreamServerToClient, MinInProcessCHTTP2)->Arg(0);
 
 }  // namespace testing
 }  // namespace grpc
diff --git a/test/cpp/microbenchmarks/bm_fullstack_unary_ping_pong.cc b/test/cpp/microbenchmarks/bm_fullstack_unary_ping_pong.cc
index b587a75d2e4..290b095cd3c 100644
--- a/test/cpp/microbenchmarks/bm_fullstack_unary_ping_pong.cc
+++ b/test/cpp/microbenchmarks/bm_fullstack_unary_ping_pong.cc
@@ -56,61 +56,6 @@ BENCHMARK_TEMPLATE(BM_UnaryPingPong, SockPair, NoOpMutator, NoOpMutator)
     ->Args({0, 0});
 BENCHMARK_TEMPLATE(BM_UnaryPingPong, MinSockPair, NoOpMutator, NoOpMutator)
     ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2, NoOpMutator, NoOpMutator)
-    ->Apply(SweepSizesArgs);
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, MinInProcessCHTTP2, NoOpMutator,
-                   NoOpMutator)
-    ->Apply(SweepSizesArgs);
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2,
-                   Client_AddMetadata<RandomBinaryMetadata<10>, 1>, NoOpMutator)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2,
-                   Client_AddMetadata<RandomBinaryMetadata<31>, 1>, NoOpMutator)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2,
-                   Client_AddMetadata<RandomBinaryMetadata<100>, 1>,
-                   NoOpMutator)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2,
-                   Client_AddMetadata<RandomBinaryMetadata<10>, 2>, NoOpMutator)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2,
-                   Client_AddMetadata<RandomBinaryMetadata<31>, 2>, NoOpMutator)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2,
-                   Client_AddMetadata<RandomBinaryMetadata<100>, 2>,
-                   NoOpMutator)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2, NoOpMutator,
-                   Server_AddInitialMetadata<RandomBinaryMetadata<10>, 1>)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2, NoOpMutator,
-                   Server_AddInitialMetadata<RandomBinaryMetadata<31>, 1>)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2, NoOpMutator,
-                   Server_AddInitialMetadata<RandomBinaryMetadata<100>, 1>)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2,
-                   Client_AddMetadata<RandomAsciiMetadata<10>, 1>, NoOpMutator)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2,
-                   Client_AddMetadata<RandomAsciiMetadata<31>, 1>, NoOpMutator)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2,
-                   Client_AddMetadata<RandomAsciiMetadata<100>, 1>, NoOpMutator)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2, NoOpMutator,
-                   Server_AddInitialMetadata<RandomAsciiMetadata<10>, 1>)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2, NoOpMutator,
-                   Server_AddInitialMetadata<RandomAsciiMetadata<31>, 1>)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2, NoOpMutator,
-                   Server_AddInitialMetadata<RandomAsciiMetadata<100>, 1>)
-    ->Args({0, 0});
-BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcessCHTTP2, NoOpMutator,
-                   Server_AddInitialMetadata<RandomAsciiMetadata<10>, 100>)
-    ->Args({0, 0});
 BENCHMARK_TEMPLATE(BM_UnaryPingPong, InProcess,
                    Client_AddMetadata<RandomBinaryMetadata<10>, 1>, NoOpMutator)
     ->Args({0, 0});
diff --git a/test/cpp/microbenchmarks/fullstack_fixtures.h b/test/cpp/microbenchmarks/fullstack_fixtures.h
index 6c395b989bd..ca3b49e0706 100644
--- a/test/cpp/microbenchmarks/fullstack_fixtures.h
+++ b/test/cpp/microbenchmarks/fullstack_fixtures.h
@@ -40,7 +40,6 @@
 #include "src/core/lib/surface/completion_queue.h"
 #include "src/core/lib/surface/server.h"
 #include "src/cpp/client/create_channel_internal.h"
-#include "test/core/util/passthru_endpoint.h"
 #include "test/core/util/port.h"
 #include "test/core/util/test_config.h"
 #include "test/cpp/microbenchmarks/helpers.h"
@@ -254,45 +253,6 @@ class SockPair : public EndpointPairFixture {
                             fixture_configuration) {}
 };
 
-// Use InProcessCHTTP2 instead. This class (with stats as an explicit parameter)
-// is here only to be able to initialize both the base class and stats_ with the
-// same stats instance without accessing the stats_ fields before the object is
-// properly initialized.
-class InProcessCHTTP2WithExplicitStats : public EndpointPairFixture {
- public:
-  InProcessCHTTP2WithExplicitStats(
-      Service* service, grpc_passthru_endpoint_stats* stats,
-      const FixtureConfiguration& fixture_configuration)
-      : EndpointPairFixture(service, MakeEndpoints(stats),
-                            fixture_configuration),
-        stats_(stats) {}
-
-  ~InProcessCHTTP2WithExplicitStats() override {
-    if (stats_ != nullptr) {
-      grpc_passthru_endpoint_stats_destroy(stats_);
-    }
-  }
-
- private:
-  grpc_passthru_endpoint_stats* stats_;
-
-  static grpc_endpoint_pair MakeEndpoints(grpc_passthru_endpoint_stats* stats) {
-    grpc_endpoint_pair p;
-    grpc_passthru_endpoint_create(&p.client, &p.server, stats);
-    return p;
-  }
-};
-
-class InProcessCHTTP2 : public InProcessCHTTP2WithExplicitStats {
- public:
-  explicit InProcessCHTTP2(Service* service,
-                           const FixtureConfiguration& fixture_configuration =
-                               FixtureConfiguration())
-      : InProcessCHTTP2WithExplicitStats(service,
-                                         grpc_passthru_endpoint_stats_create(),
-                                         fixture_configuration) {}
-};
-
 ////////////////////////////////////////////////////////////////////////////////
 // Minimal stack fixtures
 
@@ -319,7 +279,6 @@ typedef MinStackize<TCP> MinTCP;
 typedef MinStackize<UDS> MinUDS;
 typedef MinStackize<InProcess> MinInProcess;
 typedef MinStackize<SockPair> MinSockPair;
-typedef MinStackize<InProcessCHTTP2> MinInProcessCHTTP2;
 
 }  // namespace testing
 }  // namespace grpc

From ca36ff84baec83237c0e0d5ca3ecd7461b55caf4 Mon Sep 17 00:00:00 2001
From: Xuan Wang <xuanwn@google.com>
Date: Fri, 23 Feb 2024 13:23:48 -0800
Subject: [PATCH 05/16] [Python o11y] Fix readme (#35988)

Fix `readme.rst`.

Tested locally by running `python setup.py doc`, no more errors from observability.

Only error is related to grpc_status:
```
WARNING: autodoc: failed to import module 'rpc_status' from module 'grpc_status'; the following exception was raised:
cannot import name 'status_pb2' from 'google.rpc' (unknown location)
```

<!--

If you know who should review your pull request, please assign it to that
person, otherwise the pull request would get assigned randomly.

If your pull request is for a specific language, please add the appropriate
lang label.

-->

Closes #35988

PiperOrigin-RevId: 609820414
---
 doc/python/sphinx/grpc_observability.rst   |  2 +-
 doc/python/sphinx/index.rst                |  1 +
 src/python/grpcio/grpc/_observability.py   | 54 +++++++++++-----------
 src/python/grpcio_observability/README.rst |  2 +-
 4 files changed, 30 insertions(+), 29 deletions(-)

diff --git a/doc/python/sphinx/grpc_observability.rst b/doc/python/sphinx/grpc_observability.rst
index c0316f5d4f7..b79746d8fad 100644
--- a/doc/python/sphinx/grpc_observability.rst
+++ b/doc/python/sphinx/grpc_observability.rst
@@ -1,5 +1,5 @@
 gRPC Python Observability
-====================
+=========================
 
 Module Contents
 ---------------
diff --git a/doc/python/sphinx/index.rst b/doc/python/sphinx/index.rst
index 2bdd60b826d..04f190f1116 100644
--- a/doc/python/sphinx/index.rst
+++ b/doc/python/sphinx/index.rst
@@ -18,6 +18,7 @@ API Reference
    grpc_reflection
    grpc_status
    grpc_testing
+   grpc_observability
    glossary
 
 
diff --git a/src/python/grpcio/grpc/_observability.py b/src/python/grpcio/grpc/_observability.py
index 8bbbcd2bcea..3b365481922 100644
--- a/src/python/grpcio/grpc/_observability.py
+++ b/src/python/grpcio/grpc/_observability.py
@@ -74,11 +74,11 @@ class ObservabilityPlugin(
         interface and wrapped in a PyCapsule using `client_call_tracer` as name.
 
         Args:
-        method_name: The method name of the call in byte format.
-        target: The channel target of the call in byte format.
+          method_name: The method name of the call in byte format.
+          target: The channel target of the call in byte format.
 
         Returns:
-        A PyCapsule which stores a ClientCallTracer object.
+          A PyCapsule which stores a ClientCallTracer object.
         """
         raise NotImplementedError()
 
@@ -95,7 +95,7 @@ class ObservabilityPlugin(
         interface and wrapped in a PyCapsule using `client_call_tracer` as name.
 
         Args:
-        client_call_tracer: A PyCapsule which stores a ClientCallTracer object.
+          client_call_tracer: A PyCapsule which stores a ClientCallTracer object.
         """
         raise NotImplementedError()
 
@@ -111,12 +111,12 @@ class ObservabilityPlugin(
         This method can be used to propagate census context.
 
         Args:
-        trace_id: The identifier for the trace associated with the span as a
-         32-character hexadecimal encoded string,
-         e.g. 26ed0036f2eff2b7317bccce3e28d01f
-        span_id: The identifier for the span as a 16-character hexadecimal encoded
-         string. e.g. 113ec879e62583bc
-        is_sampled: A bool indicates whether the span is sampled.
+          trace_id: The identifier for the trace associated with the span as a
+            32-character hexadecimal encoded string,
+            e.g. 26ed0036f2eff2b7317bccce3e28d01f
+          span_id: The identifier for the span as a 16-character hexadecimal encoded
+            string. e.g. 113ec879e62583bc
+          is_sampled: A bool indicates whether the span is sampled.
         """
         raise NotImplementedError()
 
@@ -135,7 +135,7 @@ class ObservabilityPlugin(
         using `server_call_tracer_factory` as name.
 
         Returns:
-        A PyCapsule which stores a ServerCallTracerFactory object.
+          A PyCapsule which stores a ServerCallTracerFactory object.
         """
         raise NotImplementedError()
 
@@ -149,12 +149,12 @@ class ObservabilityPlugin(
         called at the end of each RPC.
 
         Args:
-        method: The fully-qualified name of the RPC method being invoked.
-        target: The target name of the RPC method being invoked.
-        rpc_latency: The latency for the RPC in seconds, equals to the time between
-         when the client invokes the RPC and when the client receives the status.
-        status_code: An element of grpc.StatusCode in string format representing the
-         final status for the RPC.
+          method: The fully-qualified name of the RPC method being invoked.
+          target: The target name of the RPC method being invoked.
+          rpc_latency: The latency for the RPC in seconds, equals to the time between
+            when the client invokes the RPC and when the client receives the status.
+          status_code: An element of grpc.StatusCode in string format representing the
+            final status for the RPC.
         """
         raise NotImplementedError()
 
@@ -162,7 +162,7 @@ class ObservabilityPlugin(
         """Enable or disable tracing.
 
         Args:
-        enable: A bool indicates whether tracing should be enabled.
+          enable: A bool indicates whether tracing should be enabled.
         """
         self._tracing_enabled = enable
 
@@ -170,7 +170,7 @@ class ObservabilityPlugin(
         """Enable or disable stats(metrics).
 
         Args:
-        enable: A bool indicates whether stats should be enabled.
+          enable: A bool indicates whether stats should be enabled.
         """
         self._stats_enabled = enable
 
@@ -192,7 +192,7 @@ def get_plugin() -> Generator[Optional[ObservabilityPlugin], None, None]:
     """Get the ObservabilityPlugin in _observability module.
 
     Returns:
-    The ObservabilityPlugin currently registered with the _observability
+      The ObservabilityPlugin currently registered with the _observability
     module. Or None if no plugin exists at the time of calling this method.
     """
     with _plugin_lock:
@@ -203,11 +203,11 @@ def set_plugin(observability_plugin: Optional[ObservabilityPlugin]) -> None:
     """Save ObservabilityPlugin to _observability module.
 
     Args:
-    observability_plugin: The ObservabilityPlugin to save.
+      observability_plugin: The ObservabilityPlugin to save.
 
     Raises:
       ValueError: If an ObservabilityPlugin was already registered at the
-      time of calling this method.
+        time of calling this method.
     """
     global _OBSERVABILITY_PLUGIN  # pylint: disable=global-statement
     with _plugin_lock:
@@ -223,11 +223,11 @@ def observability_init(observability_plugin: ObservabilityPlugin) -> None:
     channels/servers are built.
 
     Args:
-    observability_plugin: The ObservabilityPlugin to use.
+      observability_plugin: The ObservabilityPlugin to use.
 
     Raises:
       ValueError: If an ObservabilityPlugin was already registered at the
-      time of calling this method.
+        time of calling this method.
     """
     set_plugin(observability_plugin)
     try:
@@ -256,7 +256,7 @@ def delete_call_tracer(client_call_tracer_capsule: Any) -> None:
     interface and wrapped in a PyCapsule using `client_call_tracer` as the name.
 
     Args:
-    client_call_tracer_capsule: A PyCapsule which stores a ClientCallTracer object.
+      client_call_tracer_capsule: A PyCapsule which stores a ClientCallTracer object.
     """
     with get_plugin() as plugin:
         if not (plugin and plugin.observability_enabled):
@@ -270,8 +270,8 @@ def maybe_record_rpc_latency(state: "_channel._RPCState") -> None:
     This method will be called at the end of each RPC.
 
     Args:
-    state: a grpc._channel._RPCState object which contains the stats related to the
-    RPC.
+      state: a grpc._channel._RPCState object which contains the stats related to the
+        RPC.
     """
     # TODO(xuanwn): use channel args to exclude those metrics.
     for exclude_prefix in _SERVICES_TO_EXCLUDE:
diff --git a/src/python/grpcio_observability/README.rst b/src/python/grpcio_observability/README.rst
index 0e5df12528b..3db863b30e3 100644
--- a/src/python/grpcio_observability/README.rst
+++ b/src/python/grpcio_observability/README.rst
@@ -57,7 +57,7 @@ GCC-like stuff, but you may end up having a bad time.
 
 
 Dependencies
--------------------------
+------------
 gRPC Python Observability Depends on the following packages:
 
 ::

From ad06808bf6de241c1ae40634813a8c0504d4896b Mon Sep 17 00:00:00 2001
From: Yousuk Seung <ysseung@google.com>
Date: Fri, 23 Feb 2024 13:27:04 -0800
Subject: [PATCH 06/16] [tracing] Pass index in stream for traced byte ranges

PiperOrigin-RevId: 609821314
---
 .../chttp2/transport/context_list_entry.h     | 23 +++++++++++--------
 .../ext/transport/chttp2/transport/internal.h |  3 +++
 .../ext/transport/chttp2/transport/writing.cc |  4 +++-
 3 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/src/core/ext/transport/chttp2/transport/context_list_entry.h b/src/core/ext/transport/chttp2/transport/context_list_entry.h
index 7f42da8f175..8368d807a99 100644
--- a/src/core/ext/transport/chttp2/transport/context_list_entry.h
+++ b/src/core/ext/transport/chttp2/transport/context_list_entry.h
@@ -38,38 +38,41 @@ namespace grpc_core {
 // sent over the wire. A data chunk being written over the wire is multiplexed
 // with bytes from multiple RPCs. If one such RPC is traced, we store the
 // following information about the traced RPC:
-// - byte_offset_in_stream: Number of bytes belonging to that traced RPC which
-// have been sent so far from the start of the RPC stream.
-// - relative_start_pos_in_chunk: Starting offset of the traced RPC within
-// the current chunk that is being sent.
-// - num_traced_bytes_in_chunk: Number of bytes belonging to the traced RPC
-// within the current chunk.
 class ContextListEntry {
  public:
-  ContextListEntry(void* context, int64_t relative_start_pos,
+  ContextListEntry(void* context, int64_t outbuf_offset,
                    int64_t num_traced_bytes, size_t byte_offset,
+                   size_t stream_index,
                    std::shared_ptr<TcpTracerInterface> tcp_tracer)
       : trace_context_(context),
-        relative_start_pos_in_chunk_(relative_start_pos),
+        outbuf_offset_(outbuf_offset),
         num_traced_bytes_in_chunk_(num_traced_bytes),
         byte_offset_in_stream_(byte_offset),
+        stream_index_(stream_index),
         tcp_tracer_(std::move(tcp_tracer)) {}
 
   ContextListEntry() = delete;
 
   void* TraceContext() { return trace_context_; }
-  int64_t RelativeStartPosInChunk() { return relative_start_pos_in_chunk_; }
+  int64_t OutbufOffset() { return outbuf_offset_; }
   int64_t NumTracedBytesInChunk() { return num_traced_bytes_in_chunk_; }
   size_t ByteOffsetInStream() { return byte_offset_in_stream_; }
+  size_t StreamIndex() { return stream_index_; }
   std::shared_ptr<TcpTracerInterface> ReleaseTcpTracer() {
     return std::move(tcp_tracer_);
   }
 
  private:
   void* trace_context_;
-  int64_t relative_start_pos_in_chunk_;
+  // Offset of the head of the current chunk in the output buffer.
+  int64_t outbuf_offset_;
+  // Number of bytes traced in the current chunk.
   int64_t num_traced_bytes_in_chunk_;
+  // Offset of the head of the current chunk in the RPC stream.
   size_t byte_offset_in_stream_;
+  // Index of the current chunk in the RPC stream.
+  // Set to zero for the first chunk of the RPC stream.
+  size_t stream_index_;
   std::shared_ptr<TcpTracerInterface> tcp_tracer_;
 };
 
diff --git a/src/core/ext/transport/chttp2/transport/internal.h b/src/core/ext/transport/chttp2/transport/internal.h
index d41d6356f2a..8e0e8c522f1 100644
--- a/src/core/ext/transport/chttp2/transport/internal.h
+++ b/src/core/ext/transport/chttp2/transport/internal.h
@@ -640,6 +640,9 @@ struct grpc_chttp2_stream {
   /// Byte counter for number of bytes written
   size_t byte_counter = 0;
 
+  /// Number of times written
+  int64_t write_counter = 0;
+
   /// Only set when enabled.
   grpc_core::CallTracerInterface* call_tracer = nullptr;
 
diff --git a/src/core/ext/transport/chttp2/transport/writing.cc b/src/core/ext/transport/chttp2/transport/writing.cc
index bb812f59f0f..275c7c63691 100644
--- a/src/core/ext/transport/chttp2/transport/writing.cc
+++ b/src/core/ext/transport/chttp2/transport/writing.cc
@@ -665,6 +665,7 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
       // Add this stream to the list of the contexts to be traced at TCP
       num_stream_bytes = t->outbuf.c_slice_buffer()->length - orig_len;
       s->byte_counter += static_cast<size_t>(num_stream_bytes);
+      ++s->write_counter;
       if (s->traced && grpc_endpoint_can_track_err(t->ep)) {
         grpc_core::CopyContextFn copy_context_fn =
             grpc_core::GrpcHttp2GetCopyContextFn();
@@ -672,7 +673,8 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
             grpc_core::GrpcHttp2GetWriteTimestampsCallback() != nullptr) {
           t->cl->emplace_back(copy_context_fn(s->context),
                               outbuf_relative_start_pos, num_stream_bytes,
-                              s->byte_counter, s->tcp_tracer);
+                              s->byte_counter, s->write_counter - 1,
+                              s->tcp_tracer);
         }
       }
       outbuf_relative_start_pos += num_stream_bytes;

From 77879c4be7ec1cf8121b2a64d2f21c8f9b880f18 Mon Sep 17 00:00:00 2001
From: Yousuk Seung <ysseung@google.com>
Date: Fri, 23 Feb 2024 16:10:43 -0800
Subject: [PATCH 07/16] Clarify caller should call dtor with New()

PiperOrigin-RevId: 609863609
---
 src/core/lib/resource_quota/arena.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/core/lib/resource_quota/arena.h b/src/core/lib/resource_quota/arena.h
index edcab2caf87..fdc93621c3c 100644
--- a/src/core/lib/resource_quota/arena.h
+++ b/src/core/lib/resource_quota/arena.h
@@ -173,6 +173,8 @@ class Arena {
     }
   }
 
+  // Allocates T from the arena.
+  // The caller is responsible for calling p->~T(), but should NOT delete.
   // TODO(roth): We currently assume that all callers need alignment of 16
   // bytes, which may be wrong in some cases. When we have time, we should
   // change this to instead use the alignment of the type being allocated by
@@ -185,6 +187,7 @@ class Arena {
   }
 
   // Like New, but has the arena call p->~T() at arena destruction time.
+  // The caller should NOT delete.
   template <typename T, typename... Args>
   T* ManagedNew(Args&&... args) {
     auto* p = New<ManagedNewImpl<T>>(std::forward<Args>(args)...);

From ed065878e0d1a6083605612aa44cb030875cd90e Mon Sep 17 00:00:00 2001
From: Yousuk Seung <ysseung@google.com>
Date: Sat, 24 Feb 2024 13:21:02 -0800
Subject: [PATCH 08/16] [experiments] enable work_serializer_dispatch (posix)
 (#35992)

<!--

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Closes #35992

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35992 from yousukseung:work-serializer-windows 7b21f46dde6a7b346fca17276a45eb2da2e5d478
PiperOrigin-RevId: 610042481
---
 bazel/experiments.bzl                   | 24 ++++++------------------
 src/core/lib/experiments/experiments.cc |  2 +-
 src/core/lib/experiments/experiments.h  |  3 ++-
 src/core/lib/experiments/rollouts.yaml  |  7 ++++++-
 4 files changed, 15 insertions(+), 21 deletions(-)

diff --git a/bazel/experiments.bzl b/bazel/experiments.bzl
index 7f1380110bb..36ab8d6eb23 100644
--- a/bazel/experiments.bzl
+++ b/bazel/experiments.bzl
@@ -73,11 +73,9 @@ EXPERIMENTS = {
             ],
             "core_end2end_test": [
                 "promise_based_server_call",
-                "work_serializer_dispatch",
             ],
             "cpp_end2end_test": [
                 "promise_based_server_call",
-                "work_serializer_dispatch",
             ],
             "endpoint_test": [
                 "tcp_frame_size_tuning",
@@ -90,9 +88,6 @@ EXPERIMENTS = {
                 "tcp_frame_size_tuning",
                 "tcp_rcv_lowat",
             ],
-            "lb_unit_test": [
-                "work_serializer_dispatch",
-            ],
             "logging_test": [
                 "promise_based_server_call",
             ],
@@ -102,7 +97,6 @@ EXPERIMENTS = {
             ],
             "xds_end2end_test": [
                 "promise_based_server_call",
-                "work_serializer_dispatch",
             ],
         },
         "on": {
@@ -144,11 +138,9 @@ EXPERIMENTS = {
             ],
             "core_end2end_test": [
                 "promise_based_server_call",
-                "work_serializer_dispatch",
             ],
             "cpp_end2end_test": [
                 "promise_based_server_call",
-                "work_serializer_dispatch",
             ],
             "endpoint_test": [
                 "tcp_frame_size_tuning",
@@ -161,9 +153,6 @@ EXPERIMENTS = {
                 "tcp_frame_size_tuning",
                 "tcp_rcv_lowat",
             ],
-            "lb_unit_test": [
-                "work_serializer_dispatch",
-            ],
             "logging_test": [
                 "promise_based_server_call",
             ],
@@ -173,7 +162,6 @@ EXPERIMENTS = {
             ],
             "xds_end2end_test": [
                 "promise_based_server_call",
-                "work_serializer_dispatch",
             ],
         },
         "on": {
@@ -212,11 +200,9 @@ EXPERIMENTS = {
                 "event_engine_client",
                 "promise_based_client_call",
                 "promise_based_server_call",
-                "work_serializer_dispatch",
             ],
             "cpp_end2end_test": [
                 "promise_based_server_call",
-                "work_serializer_dispatch",
             ],
             "endpoint_test": [
                 "tcp_frame_size_tuning",
@@ -235,9 +221,6 @@ EXPERIMENTS = {
             "lame_client_test": [
                 "promise_based_client_call",
             ],
-            "lb_unit_test": [
-                "work_serializer_dispatch",
-            ],
             "logging_test": [
                 "promise_based_server_call",
             ],
@@ -247,7 +230,6 @@ EXPERIMENTS = {
             ],
             "xds_end2end_test": [
                 "promise_based_server_call",
-                "work_serializer_dispatch",
             ],
         },
         "on": {
@@ -256,6 +238,10 @@ EXPERIMENTS = {
             ],
             "core_end2end_test": [
                 "event_engine_listener",
+                "work_serializer_dispatch",
+            ],
+            "cpp_end2end_test": [
+                "work_serializer_dispatch",
             ],
             "cpp_lb_end2end_test": [
                 "pick_first_happy_eyeballs",
@@ -271,6 +257,7 @@ EXPERIMENTS = {
             "lb_unit_test": [
                 "pick_first_happy_eyeballs",
                 "round_robin_delegate_to_pick_first",
+                "work_serializer_dispatch",
                 "wrr_delegate_to_pick_first",
             ],
             "resolver_component_tests_runner_invoker": [
@@ -282,6 +269,7 @@ EXPERIMENTS = {
             "xds_end2end_test": [
                 "pick_first_happy_eyeballs",
                 "round_robin_delegate_to_pick_first",
+                "work_serializer_dispatch",
                 "wrr_delegate_to_pick_first",
             ],
         },
diff --git a/src/core/lib/experiments/experiments.cc b/src/core/lib/experiments/experiments.cc
index 9158321b54b..4ed2c0a792d 100644
--- a/src/core/lib/experiments/experiments.cc
+++ b/src/core/lib/experiments/experiments.cc
@@ -792,7 +792,7 @@ const ExperimentMetadata g_experiment_metadata[] = {
      true},
     {"work_serializer_dispatch", description_work_serializer_dispatch,
      additional_constraints_work_serializer_dispatch,
-     required_experiments_work_serializer_dispatch, 1, false, true},
+     required_experiments_work_serializer_dispatch, 1, true, true},
     {"wrr_delegate_to_pick_first", description_wrr_delegate_to_pick_first,
      additional_constraints_wrr_delegate_to_pick_first, nullptr, 0, true, true},
 };
diff --git a/src/core/lib/experiments/experiments.h b/src/core/lib/experiments/experiments.h
index 7d607aee64a..a02aaab2157 100644
--- a/src/core/lib/experiments/experiments.h
+++ b/src/core/lib/experiments/experiments.h
@@ -232,7 +232,8 @@ inline bool IsV3CompressionFilterEnabled() { return false; }
 inline bool IsV3ServerAuthFilterEnabled() { return false; }
 #define GRPC_EXPERIMENT_IS_INCLUDED_WORK_SERIALIZER_CLEARS_TIME_CACHE
 inline bool IsWorkSerializerClearsTimeCacheEnabled() { return true; }
-inline bool IsWorkSerializerDispatchEnabled() { return false; }
+#define GRPC_EXPERIMENT_IS_INCLUDED_WORK_SERIALIZER_DISPATCH
+inline bool IsWorkSerializerDispatchEnabled() { return true; }
 #define GRPC_EXPERIMENT_IS_INCLUDED_WRR_DELEGATE_TO_PICK_FIRST
 inline bool IsWrrDelegateToPickFirstEnabled() { return true; }
 #endif
diff --git a/src/core/lib/experiments/rollouts.yaml b/src/core/lib/experiments/rollouts.yaml
index 85a9ed8d472..88d076e2af4 100644
--- a/src/core/lib/experiments/rollouts.yaml
+++ b/src/core/lib/experiments/rollouts.yaml
@@ -123,6 +123,11 @@
 - name: work_serializer_clears_time_cache
   default: true
 - name: work_serializer_dispatch
-  default: false
+  default:
+    # TODO(ysseung): Not fully tested.
+    ios: broken
+    posix: true
+    # TODO(ysseung): Test flakes not fully resolved.
+    windows: broken
 - name: wrr_delegate_to_pick_first
   default: true

From 4ac804bec9062a2674bc0566743d5399e80343e2 Mon Sep 17 00:00:00 2001
From: Craig Tiller <ctiller@google.com>
Date: Sun, 25 Feb 2024 10:09:27 -0800
Subject: [PATCH 09/16] [call-v3] Correctly detect v3 filters even if the
 immediate base class is not ImplementCallFilter<> (#35997)

Fixes max_age filter not getting a v3 init_call implementation

Closes #35997

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35997 from ctiller:naughty df17e57e91cc9a951ef413385429d8d04659111d
PiperOrigin-RevId: 610194630
---
 src/core/ext/filters/channel_idle/channel_idle_filter.cc | 1 +
 src/core/lib/channel/promise_based_filter.h              | 8 +++++---
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/core/ext/filters/channel_idle/channel_idle_filter.cc b/src/core/ext/filters/channel_idle/channel_idle_filter.cc
index 8e5fead77a2..880d10ab01c 100644
--- a/src/core/ext/filters/channel_idle/channel_idle_filter.cc
+++ b/src/core/ext/filters/channel_idle/channel_idle_filter.cc
@@ -294,6 +294,7 @@ const grpc_channel_filter MaxAgeFilter::kFilter =
     MakePromiseBasedFilter<MaxAgeFilter, FilterEndpoint::kServer>("max_age");
 
 void RegisterChannelIdleFilters(CoreConfiguration::Builder* builder) {
+  GPR_ASSERT(MaxAgeFilter::kFilter.init_call != nullptr);
   if (!IsV3ChannelIdleFiltersEnabled()) return;
   builder->channel_init()
       ->RegisterFilter<ClientIdleFilter>(GRPC_CLIENT_CHANNEL)
diff --git a/src/core/lib/channel/promise_based_filter.h b/src/core/lib/channel/promise_based_filter.h
index bb642bc7f21..971e98895b1 100644
--- a/src/core/lib/channel/promise_based_filter.h
+++ b/src/core/lib/channel/promise_based_filter.h
@@ -1065,8 +1065,10 @@ MakeFilterCall(Derived* derived) {
 //   the filter does not intercept call finalization.
 // - void OnFinalize(const grpc_call_final_info*):
 //   the filter intercepts call finalization.
+class ImplementChannelFilterTag {};
 template <typename Derived>
-class ImplementChannelFilter : public ChannelFilter {
+class ImplementChannelFilter : public ChannelFilter,
+                               public ImplementChannelFilterTag {
  public:
   // Natively construct a v3 call.
   void InitCall(CallSpineInterface* call_spine) {
@@ -1914,7 +1916,7 @@ struct ChannelFilterWithFlagsMethods {
 template <typename F, FilterEndpoint kEndpoint, uint8_t kFlags = 0>
 absl::enable_if_t<
     std::is_base_of<ChannelFilter, F>::value &&
-        !std::is_base_of<ImplementChannelFilter<F>, F>::value &&
+        !std::is_base_of<ImplementChannelFilterTag, F>::value &&
         !std::is_base_of<HackyHackyHackySkipInV3FilterStacks, F>::value,
     grpc_channel_filter>
 MakePromiseBasedFilter(const char* name) {
@@ -2001,7 +2003,7 @@ MakePromiseBasedFilter(const char* name) {
 }
 
 template <typename F, FilterEndpoint kEndpoint, uint8_t kFlags = 0>
-absl::enable_if_t<std::is_base_of<ImplementChannelFilter<F>, F>::value,
+absl::enable_if_t<std::is_base_of<ImplementChannelFilterTag, F>::value,
                   grpc_channel_filter>
 MakePromiseBasedFilter(const char* name) {
   using CallData = promise_filter_detail::CallData<kEndpoint>;

From d2efbfe449b6696c9ef96646362e50d58e5a7265 Mon Sep 17 00:00:00 2001
From: Craig Tiller <ctiller@google.com>
Date: Sun, 25 Feb 2024 21:35:17 -0800
Subject: [PATCH 10/16] Log gRPC experiments at INFO

Often we need to debug something after a crash and this set of breadcrumbs would be hugely beneficial.

PiperOrigin-RevId: 610285566
---
 src/core/lib/experiments/config.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/core/lib/experiments/config.cc b/src/core/lib/experiments/config.cc
index 24c5cceb12b..6a480c22db1 100644
--- a/src/core/lib/experiments/config.cc
+++ b/src/core/lib/experiments/config.cc
@@ -201,7 +201,7 @@ void PrintExperimentsList() {
   for (auto name_index : visitation_order) {
     const size_t i = name_index.second;
     gpr_log(
-        GPR_DEBUG, "%s",
+        GPR_INFO, "%s",
         absl::StrCat(
             "gRPC EXPERIMENT ", g_experiment_metadata[i].name,
             std::string(max_experiment_length -

From d4afc993ed0f1fdf9ca3663181222df9504a5f93 Mon Sep 17 00:00:00 2001
From: Jan Katins <jan.katins@katzien.de>
Date: Mon, 26 Feb 2024 18:22:44 +0100
Subject: [PATCH 11/16] [python] Fix typo in code comment (#35981)

Found this while reading the code.
---
 src/python/grpcio/grpc/aio/_interceptor.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/python/grpcio/grpc/aio/_interceptor.py b/src/python/grpcio/grpc/aio/_interceptor.py
index 38312b7955b..e7ceb00fbbf 100644
--- a/src/python/grpcio/grpc/aio/_interceptor.py
+++ b/src/python/grpcio/grpc/aio/_interceptor.py
@@ -476,7 +476,7 @@ class _InterceptedStreamResponseMixin:
     _response_aiter: Optional[AsyncIterable[ResponseType]]
 
     def _init_stream_response_mixin(self) -> None:
-        # Is initalized later, otherwise if the iterator is not finnally
+        # Is initalized later, otherwise if the iterator is not finally
         # consumed a logging warning is emmited by Asyncio.
         self._response_aiter = None
 

From 641213ee58aa8f430d4753a546af688562a3e1c1 Mon Sep 17 00:00:00 2001
From: Yousuk Seung <ysseung@google.com>
Date: Mon, 26 Feb 2024 11:20:00 -0800
Subject: [PATCH 12/16] [tracing] Remove debugging annotations

PiperOrigin-RevId: 610469149
---
 .../chttp2/transport/chttp2_transport.cc      | 38 ++++++------------
 .../ext/transport/chttp2/transport/internal.h |  1 -
 .../ext/transport/chttp2/transport/writing.cc | 32 +++++++--------
 src/core/lib/surface/call.cc                  | 39 +++----------------
 src/python/grpcio/grpc/aio/_interceptor.py    |  2 +-
 5 files changed, 33 insertions(+), 79 deletions(-)

diff --git a/src/core/ext/transport/chttp2/transport/chttp2_transport.cc b/src/core/ext/transport/chttp2/transport/chttp2_transport.cc
index 5f851d60a07..9c767bdd07e 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_transport.cc
+++ b/src/core/ext/transport/chttp2/transport/chttp2_transport.cc
@@ -1300,7 +1300,6 @@ static void null_then_sched_closure(grpc_closure** closure) {
 }
 
 void grpc_chttp2_complete_closure_step(grpc_chttp2_transport* t,
-                                       grpc_chttp2_stream* s,
                                        grpc_closure** pclosure,
                                        grpc_error_handle error,
                                        const char* desc,
@@ -1325,12 +1324,6 @@ void grpc_chttp2_complete_closure_step(grpc_chttp2_transport* t,
         write_state_name(t->write_state), whence.file(), whence.line());
   }
 
-  if (s->call_tracer) {
-    s->call_tracer->RecordAnnotation(
-        absl::StrFormat("on_complete: s=%p %p desc=%s err=%s", s, closure, desc,
-                        grpc_core::StatusToString(error).c_str()));
-  }
-
   if (!error.ok()) {
     grpc_error_handle cl_err =
         grpc_core::internal::StatusMoveFromHeapPtr(closure->error_data.error);
@@ -1405,13 +1398,6 @@ static void perform_stream_op_locked(void* stream_op,
     }
   }
 
-  if (s->call_tracer) {
-    s->call_tracer->RecordAnnotation(absl::StrFormat(
-        "perform_stream_op_locked[s=%p; op=%p]: %s; on_complete = %p", s, op,
-        grpc_transport_stream_op_batch_string(op, true).c_str(),
-        op->on_complete));
-  }
-
   grpc_closure* on_complete = op->on_complete;
   // on_complete will be null if and only if there are no send ops in the batch.
   if (on_complete != nullptr) {
@@ -1483,7 +1469,7 @@ static void perform_stream_op_locked(void* stream_op,
     } else {
       s->send_initial_metadata = nullptr;
       grpc_chttp2_complete_closure_step(
-          t, s, &s->send_initial_metadata_finished,
+          t, &s->send_initial_metadata_finished,
           GRPC_ERROR_CREATE_REFERENCING(
               "Attempt to send initial metadata after stream was closed",
               &s->write_closed_error, 1),
@@ -1503,7 +1489,7 @@ static void perform_stream_op_locked(void* stream_op,
       // We should NOT return an error here, so as to avoid a cancel OP being
       // started. The surface layer will notice that the stream has been closed
       // for writes and fail the send message op.
-      grpc_chttp2_complete_closure_step(t, s, &s->send_message_finished,
+      grpc_chttp2_complete_closure_step(t, &s->send_message_finished,
                                         absl::OkStatus(),
                                         "fetching_send_message_finished");
     } else {
@@ -1543,7 +1529,7 @@ static void perform_stream_op_locked(void* stream_op,
 
       int64_t notify_offset = s->next_message_end_offset;
       if (notify_offset <= s->flow_controlled_bytes_written) {
-        grpc_chttp2_complete_closure_step(t, s, &s->send_message_finished,
+        grpc_chttp2_complete_closure_step(t, &s->send_message_finished,
                                           absl::OkStatus(),
                                           "fetching_send_message_finished");
       } else {
@@ -1587,7 +1573,7 @@ static void perform_stream_op_locked(void* stream_op,
       s->send_trailing_metadata = nullptr;
       s->sent_trailing_metadata_op = nullptr;
       grpc_chttp2_complete_closure_step(
-          t, s, &s->send_trailing_metadata_finished,
+          t, &s->send_trailing_metadata_finished,
           op->payload->send_trailing_metadata.send_trailing_metadata->empty()
               ? absl::OkStatus()
               : GRPC_ERROR_CREATE("Attempt to send trailing metadata after "
@@ -1640,7 +1626,7 @@ static void perform_stream_op_locked(void* stream_op,
   }
 
   if (on_complete != nullptr) {
-    grpc_chttp2_complete_closure_step(t, s, &on_complete, absl::OkStatus(),
+    grpc_chttp2_complete_closure_step(t, &on_complete, absl::OkStatus(),
                                       "op->on_complete");
   }
 
@@ -2307,13 +2293,13 @@ static grpc_error_handle removal_error(grpc_error_handle extra_error,
   return error;
 }
 
-static void flush_write_list(grpc_chttp2_transport* t, grpc_chttp2_stream* s,
+static void flush_write_list(grpc_chttp2_transport* t,
                              grpc_chttp2_write_cb** list,
                              grpc_error_handle error) {
   while (*list) {
     grpc_chttp2_write_cb* cb = *list;
     *list = cb->next;
-    grpc_chttp2_complete_closure_step(t, s, &cb->closure, error,
+    grpc_chttp2_complete_closure_step(t, &cb->closure, error,
                                       "on_write_finished_cb");
     cb->next = t->write_cb_pool;
     t->write_cb_pool = cb;
@@ -2326,18 +2312,18 @@ void grpc_chttp2_fail_pending_writes(grpc_chttp2_transport* t,
   error =
       removal_error(error, s, "Pending writes failed due to stream closure");
   s->send_initial_metadata = nullptr;
-  grpc_chttp2_complete_closure_step(t, s, &s->send_initial_metadata_finished,
+  grpc_chttp2_complete_closure_step(t, &s->send_initial_metadata_finished,
                                     error, "send_initial_metadata_finished");
 
   s->send_trailing_metadata = nullptr;
   s->sent_trailing_metadata_op = nullptr;
-  grpc_chttp2_complete_closure_step(t, s, &s->send_trailing_metadata_finished,
+  grpc_chttp2_complete_closure_step(t, &s->send_trailing_metadata_finished,
                                     error, "send_trailing_metadata_finished");
 
-  grpc_chttp2_complete_closure_step(t, s, &s->send_message_finished, error,
+  grpc_chttp2_complete_closure_step(t, &s->send_message_finished, error,
                                     "fetching_send_message_finished");
-  flush_write_list(t, s, &s->on_write_finished_cbs, error);
-  flush_write_list(t, s, &s->on_flow_controlled_cbs, error);
+  flush_write_list(t, &s->on_write_finished_cbs, error);
+  flush_write_list(t, &s->on_flow_controlled_cbs, error);
 }
 
 grpc_chttp2_transport::RemovedStreamHandle grpc_chttp2_mark_stream_closed(
diff --git a/src/core/ext/transport/chttp2/transport/internal.h b/src/core/ext/transport/chttp2/transport/internal.h
index 8e0e8c522f1..94976850645 100644
--- a/src/core/ext/transport/chttp2/transport/internal.h
+++ b/src/core/ext/transport/chttp2/transport/internal.h
@@ -778,7 +778,6 @@ void grpc_chttp2_add_incoming_goaway(grpc_chttp2_transport* t,
 void grpc_chttp2_parsing_become_skip_parser(grpc_chttp2_transport* t);
 
 void grpc_chttp2_complete_closure_step(grpc_chttp2_transport* t,
-                                       grpc_chttp2_stream* s,
                                        grpc_closure** pclosure,
                                        grpc_error_handle error,
                                        const char* desc,
diff --git a/src/core/ext/transport/chttp2/transport/writing.cc b/src/core/ext/transport/chttp2/transport/writing.cc
index 275c7c63691..5357b2ccf22 100644
--- a/src/core/ext/transport/chttp2/transport/writing.cc
+++ b/src/core/ext/transport/chttp2/transport/writing.cc
@@ -82,10 +82,9 @@ static void add_to_write_list(grpc_chttp2_write_cb** list,
   *list = cb;
 }
 
-static void finish_write_cb(grpc_chttp2_transport* t, grpc_chttp2_stream* s,
-                            grpc_chttp2_write_cb* cb, grpc_error_handle error) {
-  grpc_chttp2_complete_closure_step(t, s, &cb->closure, error,
-                                    "finish_write_cb");
+static void finish_write_cb(grpc_chttp2_transport* t, grpc_chttp2_write_cb* cb,
+                            grpc_error_handle error) {
+  grpc_chttp2_complete_closure_step(t, &cb->closure, error, "finish_write_cb");
   cb->next = t->write_cb_pool;
   t->write_cb_pool = cb;
 }
@@ -186,9 +185,9 @@ static void maybe_initiate_ping(grpc_chttp2_transport* t) {
       });
 }
 
-static bool update_list(grpc_chttp2_transport* t, grpc_chttp2_stream* s,
-                        int64_t send_bytes, grpc_chttp2_write_cb** list,
-                        int64_t* ctr, grpc_error_handle error) {
+static bool update_list(grpc_chttp2_transport* t, int64_t send_bytes,
+                        grpc_chttp2_write_cb** list, int64_t* ctr,
+                        grpc_error_handle error) {
   bool sched_any = false;
   grpc_chttp2_write_cb* cb = *list;
   *list = nullptr;
@@ -197,7 +196,7 @@ static bool update_list(grpc_chttp2_transport* t, grpc_chttp2_stream* s,
     grpc_chttp2_write_cb* next = cb->next;
     if (cb->call_at_byte <= *ctr) {
       sched_any = true;
-      finish_write_cb(t, s, cb, error);
+      finish_write_cb(t, cb, error);
     } else {
       add_to_write_list(list, cb);
     }
@@ -424,8 +423,7 @@ class DataSendContext {
 
   void CallCallbacks() {
     if (update_list(
-            t_, s_,
-            static_cast<int64_t>(s_->sending_bytes - sending_bytes_before_),
+            t_, static_cast<int64_t>(s_->sending_bytes - sending_bytes_before_),
             &s_->on_flow_controlled_cbs, &s_->flow_controlled_bytes_flowed,
             absl::OkStatus())) {
       write_context_->NoteScheduledResults();
@@ -484,9 +482,9 @@ class StreamWriteContext {
     s_->send_initial_metadata = nullptr;
     s_->sent_initial_metadata = true;
     write_context_->NoteScheduledResults();
-    grpc_chttp2_complete_closure_step(
-        t_, s_, &s_->send_initial_metadata_finished, absl::OkStatus(),
-        "send_initial_metadata_finished");
+    grpc_chttp2_complete_closure_step(t_, &s_->send_initial_metadata_finished,
+                                      absl::OkStatus(),
+                                      "send_initial_metadata_finished");
     if (s_->call_tracer) {
       grpc_core::HttpAnnotation::WriteStats write_stats;
       write_stats.target_write_size = write_context_->target_write_size();
@@ -583,9 +581,9 @@ class StreamWriteContext {
     SentLastFrame();
 
     write_context_->NoteScheduledResults();
-    grpc_chttp2_complete_closure_step(
-        t_, s_, &s_->send_trailing_metadata_finished, absl::OkStatus(),
-        "send_trailing_metadata_finished");
+    grpc_chttp2_complete_closure_step(t_, &s_->send_trailing_metadata_finished,
+                                      absl::OkStatus(),
+                                      "send_trailing_metadata_finished");
   }
 
   bool stream_became_writable() { return stream_became_writable_; }
@@ -746,7 +744,7 @@ void grpc_chttp2_end_write(grpc_chttp2_transport* t, grpc_error_handle error) {
 
   while (grpc_chttp2_list_pop_writing_stream(t, &s)) {
     if (s->sending_bytes != 0) {
-      update_list(t, s, static_cast<int64_t>(s->sending_bytes),
+      update_list(t, static_cast<int64_t>(s->sending_bytes),
                   &s->on_write_finished_cbs, &s->flow_controlled_bytes_written,
                   error);
       s->sending_bytes = 0;
diff --git a/src/core/lib/surface/call.cc b/src/core/lib/surface/call.cc
index 3074c042602..b4e66974aaf 100644
--- a/src/core/lib/surface/call.cc
+++ b/src/core/lib/surface/call.cc
@@ -648,31 +648,12 @@ class FilterStackCall final : public Call {
     }
     bool completed_batch_step(PendingOp op) {
       auto mask = PendingOpMask(op);
-      // Acquire call tracer before ops_pending_.fetch_sub to avoid races with
-      // call_ being set to nullptr in PostCompletion method. Store the
-      // call_tracer_ and call_ variables locally as well because they could be
-      // modified by another thread after the fetch_sub operation.
-      CallTracerAnnotationInterface* call_tracer = call_tracer_;
-      FilterStackCall* call = call_;
-      bool is_call_trace_enabled = grpc_call_trace.enabled();
-      bool is_call_ops_annotate_enabled =
-          (IsTraceRecordCallopsEnabled() && call_tracer != nullptr);
-      if (is_call_ops_annotate_enabled) {
-        call->InternalRef("Call ops annotate");
-      }
       auto r = ops_pending_.fetch_sub(mask, std::memory_order_acq_rel);
-      if (is_call_trace_enabled || is_call_ops_annotate_enabled) {
-        std::string trace_string = absl::StrFormat(
-            "BATCH:%p COMPLETE:%s REMAINING:%s (tag:%p)", this,
-            PendingOpString(mask).c_str(), PendingOpString(r & ~mask).c_str(),
-            completion_data_.notify_tag.tag);
-        if (is_call_trace_enabled) {
-          gpr_log(GPR_DEBUG, "%s", trace_string.c_str());
-        }
-        if (is_call_ops_annotate_enabled) {
-          call_tracer->RecordAnnotation(trace_string);
-          call->InternalUnref("Call ops annotate");
-        }
+      if (grpc_call_trace.enabled()) {
+        gpr_log(GPR_DEBUG, "BATCH:%p COMPLETE:%s REMAINING:%s (tag:%p)", this,
+                PendingOpString(mask).c_str(),
+                PendingOpString(r & ~mask).c_str(),
+                completion_data_.notify_tag.tag);
       }
       GPR_ASSERT((r & mask) != 0);
       return r == mask;
@@ -1538,7 +1519,6 @@ grpc_call_error FilterStackCall::StartBatch(const grpc_op* ops, size_t nops,
   grpc_transport_stream_op_batch_payload* stream_op_payload;
   uint32_t seen_ops = 0;
   intptr_t pending_ops = 0;
-  CallTracerAnnotationInterface* call_tracer = nullptr;
 
   for (i = 0; i < nops; i++) {
     if (seen_ops & (1u << ops[i].op)) {
@@ -1899,15 +1879,6 @@ grpc_call_error FilterStackCall::StartBatch(const grpc_op* ops, size_t nops,
     stream_op->on_complete = &bctl->finish_batch_;
   }
 
-  call_tracer = static_cast<CallTracerAnnotationInterface*>(
-      ContextGet(GRPC_CONTEXT_CALL_TRACER_ANNOTATION_INTERFACE));
-  if ((IsTraceRecordCallopsEnabled() && call_tracer != nullptr)) {
-    call_tracer->RecordAnnotation(absl::StrFormat(
-        "BATCH:%p START:%s BATCH:%s (tag:%p)", bctl,
-        PendingOpString(pending_ops).c_str(),
-        grpc_transport_stream_op_batch_string(stream_op, true).c_str(),
-        bctl->completion_data_.notify_tag.tag));
-  }
   if (grpc_call_trace.enabled()) {
     gpr_log(GPR_DEBUG, "BATCH:%p START:%s BATCH:%s (tag:%p)", bctl,
             PendingOpString(pending_ops).c_str(),
diff --git a/src/python/grpcio/grpc/aio/_interceptor.py b/src/python/grpcio/grpc/aio/_interceptor.py
index e7ceb00fbbf..38312b7955b 100644
--- a/src/python/grpcio/grpc/aio/_interceptor.py
+++ b/src/python/grpcio/grpc/aio/_interceptor.py
@@ -476,7 +476,7 @@ class _InterceptedStreamResponseMixin:
     _response_aiter: Optional[AsyncIterable[ResponseType]]
 
     def _init_stream_response_mixin(self) -> None:
-        # Is initalized later, otherwise if the iterator is not finally
+        # Is initalized later, otherwise if the iterator is not finnally
         # consumed a logging warning is emmited by Asyncio.
         self._response_aiter = None
 

From a1b7e1e523ec5737e156481b1cf62cf377d3d27a Mon Sep 17 00:00:00 2001
From: Gregory Cooke <gregorycooke@google.com>
Date: Mon, 26 Feb 2024 13:09:55 -0800
Subject: [PATCH 13/16] [Security] Crl helpers (#35963)

Re-applies after the revert
Fixes the Openssl 1.0.2 portability errors

Closes #35963

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35963 from gtcooke94:CrlHelpers 9cfb401a47ac0d553d3243ff9e7008a356051690
PiperOrigin-RevId: 610503595
---
 BUILD                                         |   1 +
 CMakeLists.txt                                |   2 +
 build_autogenerated.yaml                      |   6 +-
 .../credentials/tls/grpc_tls_crl_provider.cc  |  27 ++-
 src/core/tsi/ssl_transport_security.cc        |   9 +-
 src/core/tsi/ssl_transport_security_utils.cc  |  70 ++++++
 src/core/tsi/ssl_transport_security_utils.h   |  18 ++
 src/python/grpcio/grpc/aio/_interceptor.py    |   2 +-
 test/core/security/BUILD                      |   2 +
 .../security/grpc_tls_crl_provider_test.cc    |  67 ++++--
 test/core/tsi/BUILD                           |  11 +
 .../tsi/ssl_transport_security_utils_test.cc  | 208 +++++++++++++++++-
 test/core/tsi/test_creds/crl_data/BUILD       |   1 +
 test/core/tsi/test_creds/crl_data/README      |   5 +
 test/core/tsi/test_creds/crl_data/crls/BUILD  |   2 +
 .../crl_data/crls/invalid_content.crl         |  15 ++
 .../crl_data/crls/invalid_signature.crl       |  15 ++
 test/core/tsi/test_creds/crl_data/evil_ca.key |  28 +++
 test/core/tsi/test_creds/crl_data/evil_ca.pem |  21 ++
 .../tsi/test_creds/crl_data/evil_ca_gen.sh    |  18 ++
 .../test_creds/crl_data/intermediate_gen.sh   |   2 -
 test/core/tsi/transport_security_test_lib.cc  |  24 ++
 test/core/tsi/transport_security_test_lib.h   |   8 +
 23 files changed, 518 insertions(+), 44 deletions(-)
 create mode 100644 test/core/tsi/test_creds/crl_data/crls/invalid_content.crl
 create mode 100644 test/core/tsi/test_creds/crl_data/crls/invalid_signature.crl
 create mode 100644 test/core/tsi/test_creds/crl_data/evil_ca.key
 create mode 100644 test/core/tsi/test_creds/crl_data/evil_ca.pem
 create mode 100644 test/core/tsi/test_creds/crl_data/evil_ca_gen.sh

diff --git a/BUILD b/BUILD
index 96b6778cb0f..af9e76174d4 100644
--- a/BUILD
+++ b/BUILD
@@ -3879,6 +3879,7 @@ grpc_cc_library(
     external_deps = [
         "absl/base:core_headers",
         "absl/status",
+        "absl/status:statusor",
         "absl/strings",
         "libcrypto",
         "libssl",
diff --git a/CMakeLists.txt b/CMakeLists.txt
index fb3dc1cb780..6be079f93a5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -15896,6 +15896,7 @@ add_executable(grpc_tls_crl_provider_test
   test/core/event_engine/event_engine_test_utils.cc
   test/core/event_engine/fuzzing_event_engine/fuzzing_event_engine.cc
   test/core/security/grpc_tls_crl_provider_test.cc
+  test/core/tsi/transport_security_test_lib.cc
 )
 if(WIN32 AND MSVC)
   if(BUILD_SHARED_LIBS)
@@ -28070,6 +28071,7 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 
   add_executable(ssl_transport_security_utils_test
     test/core/tsi/ssl_transport_security_utils_test.cc
+    test/core/tsi/transport_security_test_lib.cc
   )
   if(WIN32 AND MSVC)
     if(BUILD_SHARED_LIBS)
diff --git a/build_autogenerated.yaml b/build_autogenerated.yaml
index ea4c8a834f7..cd50e12b948 100644
--- a/build_autogenerated.yaml
+++ b/build_autogenerated.yaml
@@ -10702,12 +10702,14 @@ targets:
   headers:
   - test/core/event_engine/event_engine_test_utils.h
   - test/core/event_engine/fuzzing_event_engine/fuzzing_event_engine.h
+  - test/core/tsi/transport_security_test_lib.h
   src:
   - test/core/event_engine/fuzzing_event_engine/fuzzing_event_engine.proto
   - test/core/util/fuzz_config_vars.proto
   - test/core/event_engine/event_engine_test_utils.cc
   - test/core/event_engine/fuzzing_event_engine/fuzzing_event_engine.cc
   - test/core/security/grpc_tls_crl_provider_test.cc
+  - test/core/tsi/transport_security_test_lib.cc
   deps:
   - gtest
   - protobuf
@@ -17928,9 +17930,11 @@ targets:
   gtest: true
   build: test
   language: c++
-  headers: []
+  headers:
+  - test/core/tsi/transport_security_test_lib.h
   src:
   - test/core/tsi/ssl_transport_security_utils_test.cc
+  - test/core/tsi/transport_security_test_lib.cc
   deps:
   - gtest
   - grpc_test_util
diff --git a/src/core/lib/security/credentials/tls/grpc_tls_crl_provider.cc b/src/core/lib/security/credentials/tls/grpc_tls_crl_provider.cc
index f9c0868f7c1..f8adf5f12cc 100644
--- a/src/core/lib/security/credentials/tls/grpc_tls_crl_provider.cc
+++ b/src/core/lib/security/credentials/tls/grpc_tls_crl_provider.cc
@@ -53,15 +53,22 @@ namespace grpc_core {
 namespace experimental {
 
 namespace {
-std::string IssuerFromCrl(X509_CRL* crl) {
+// TODO(gtcooke94) Move ssl_transport_security_utils to it's own BUILD target
+// and add this to it.
+absl::StatusOr<std::string> IssuerFromCrl(X509_CRL* crl) {
   if (crl == nullptr) {
-    return "";
+    return absl::InvalidArgumentError("crl cannot be null");
   }
-  char* buf = X509_NAME_oneline(X509_CRL_get_issuer(crl), nullptr, 0);
-  std::string ret;
-  if (buf != nullptr) {
-    ret = buf;
+  X509_NAME* issuer = X509_CRL_get_issuer(crl);
+  if (issuer == nullptr) {
+    return absl::InvalidArgumentError("crl cannot have null issuer");
   }
+  unsigned char* buf = nullptr;
+  int len = i2d_X509_NAME(issuer, &buf);
+  if (len < 0 || buf == nullptr) {
+    return absl::InvalidArgumentError("crl cannot have null issuer");
+  }
+  std::string ret(reinterpret_cast<char const*>(buf), len);
   OPENSSL_free(buf);
   return ret;
 }
@@ -103,11 +110,11 @@ absl::StatusOr<std::unique_ptr<Crl>> Crl::Parse(absl::string_view crl_string) {
 }
 
 absl::StatusOr<std::unique_ptr<CrlImpl>> CrlImpl::Create(X509_CRL* crl) {
-  std::string issuer = IssuerFromCrl(crl);
-  if (issuer.empty()) {
-    return absl::InvalidArgumentError("Issuer of crl cannot be empty");
+  absl::StatusOr<std::string> issuer = IssuerFromCrl(crl);
+  if (!issuer.ok()) {
+    return issuer.status();
   }
-  return std::make_unique<CrlImpl>(crl, issuer);
+  return std::make_unique<CrlImpl>(crl, *issuer);
 }
 
 CrlImpl::~CrlImpl() { X509_CRL_free(crl_); }
diff --git a/src/core/tsi/ssl_transport_security.cc b/src/core/tsi/ssl_transport_security.cc
index 7bba63a63f0..c9082e8c192 100644
--- a/src/core/tsi/ssl_transport_security.cc
+++ b/src/core/tsi/ssl_transport_security.cc
@@ -1004,15 +1004,14 @@ static int GetCrlFromProvider(X509_STORE_CTX* ctx, X509_CRL** crl_out,
   auto* provider = static_cast<grpc_core::experimental::CrlProvider*>(
       SSL_CTX_get_ex_data(ssl_ctx, g_ssl_ctx_ex_crl_provider_index));
 
-  char* buf = X509_NAME_oneline(X509_get_issuer_name(cert), nullptr, 0);
-  if (buf == nullptr) {
-    gpr_log(GPR_ERROR, "Certificate has null issuer, cannot do CRL lookup");
+  absl::StatusOr<std::string> issuer_name = grpc_core::IssuerFromCert(cert);
+  if (!issuer_name.ok()) {
+    gpr_log(GPR_INFO, "Could not get certificate issuer name");
     return 0;
   }
-  grpc_core::experimental::CertificateInfoImpl cert_impl(buf);
+  grpc_core::experimental::CertificateInfoImpl cert_impl(*issuer_name);
   std::shared_ptr<grpc_core::experimental::Crl> internal_crl =
       provider->GetCrl(cert_impl);
-  OPENSSL_free(buf);
   // There wasn't a CRL found in the provider. Returning 0 will end up causing
   // OpenSSL to return X509_V_ERR_UNABLE_TO_GET_CRL. We then catch that error
   // and behave how we want for a missing CRL.
diff --git a/src/core/tsi/ssl_transport_security_utils.cc b/src/core/tsi/ssl_transport_security_utils.cc
index 7d258046600..62bf21a2eed 100644
--- a/src/core/tsi/ssl_transport_security_utils.cc
+++ b/src/core/tsi/ssl_transport_security_utils.cc
@@ -23,6 +23,10 @@
 #include <openssl/crypto.h>
 #include <openssl/err.h>
 #include <openssl/ssl.h>
+#include <openssl/x509v3.h>
+
+#include "absl/status/status.h"
+#include "absl/status/statusor.h"
 
 #include "src/core/tsi/transport_security_interface.h"
 
@@ -247,4 +251,70 @@ tsi_result SslProtectorUnprotect(const unsigned char* protected_frames_bytes,
   return result;
 }
 
+bool VerifyCrlSignature(X509_CRL* crl, X509* issuer) {
+  if (issuer == nullptr || crl == nullptr) {
+    return false;
+  }
+  EVP_PKEY* ikey = X509_get_pubkey(issuer);
+  if (ikey == nullptr) {
+    // Can't verify signature because we couldn't get the pubkey, fail the
+    // check.
+    EVP_PKEY_free(ikey);
+    return false;
+  }
+  bool ret = X509_CRL_verify(crl, ikey) == 1;
+  EVP_PKEY_free(ikey);
+  return ret;
+}
+
+bool VerifyCrlCertIssuerNamesMatch(X509_CRL* crl, X509* cert) {
+  if (cert == nullptr || crl == nullptr) {
+    return false;
+  }
+  X509_NAME* cert_issuer_name = X509_get_issuer_name(cert);
+  if (cert == nullptr) {
+    return false;
+  }
+  X509_NAME* crl_issuer_name = X509_CRL_get_issuer(crl);
+  if (crl_issuer_name == nullptr) {
+    return false;
+  }
+  return X509_NAME_cmp(cert_issuer_name, crl_issuer_name) == 0;
+}
+
+bool HasCrlSignBit(X509* cert) {
+  if (cert == nullptr) {
+    return false;
+  }
+  // X509_get_key_usage was introduced in 1.1.1
+  // A missing key usage extension means all key usages are valid.
+#if OPENSSL_VERSION_NUMBER < 0x10100000
+  // X509_check_ca sets cert->ex_flags. We dont use the return value, but those
+  // flags being set is important.
+  // https://github.com/openssl/openssl/blob/e818b74be2170fbe957a07b0da4401c2b694b3b8/crypto/x509v3/v3_purp.c#L585
+  X509_check_ca(cert);
+  if (!(cert->ex_flags & EXFLAG_KUSAGE)) {
+    return true;
+  }
+  return (cert->ex_kusage & KU_CRL_SIGN) != 0;
+#else
+  return (X509_get_key_usage(cert) & KU_CRL_SIGN) != 0;
+#endif  // OPENSSL_VERSION_NUMBER < 0x10100000
+}
+
+absl::StatusOr<std::string> IssuerFromCert(X509* cert) {
+  if (cert == nullptr) {
+    return absl::InvalidArgumentError("cert cannot be null");
+  }
+  X509_NAME* issuer = X509_get_issuer_name(cert);
+  unsigned char* buf = nullptr;
+  int len = i2d_X509_NAME(issuer, &buf);
+  if (len < 0 || buf == nullptr) {
+    return absl::InvalidArgumentError("could not read issuer name from cert");
+  }
+  std::string ret(reinterpret_cast<char const*>(buf), len);
+  OPENSSL_free(buf);
+  return ret;
+}
+
 }  // namespace grpc_core
diff --git a/src/core/tsi/ssl_transport_security_utils.h b/src/core/tsi/ssl_transport_security_utils.h
index 14b38e644d1..22cacc84fbc 100644
--- a/src/core/tsi/ssl_transport_security_utils.h
+++ b/src/core/tsi/ssl_transport_security_utils.h
@@ -23,6 +23,8 @@
 
 #include <openssl/x509.h>
 
+#include "absl/status/status.h"
+#include "absl/status/statusor.h"
 #include "absl/strings/string_view.h"
 
 #include <grpc/grpc_security_constants.h>
@@ -142,6 +144,22 @@ tsi_result SslProtectorUnprotect(const unsigned char* protected_frames_bytes,
                                  unsigned char* unprotected_bytes,
                                  size_t* unprotected_bytes_size);
 
+// Verifies that `crl` was signed by `issuer.
+// return: true if valid, false otherwise.
+bool VerifyCrlSignature(X509_CRL* crl, X509* issuer);
+
+// Verifies the CRL issuer and certificate issuer name match.
+// return: true if equal, false if not.
+bool VerifyCrlCertIssuerNamesMatch(X509_CRL* crl, X509* cert);
+
+// Verifies the certificate in question has the cRLSign bit present.
+// return: true if cRLSign bit is present, false otherwise.
+bool HasCrlSignBit(X509* cert);
+
+// Gets a stable representation of the issuer name from an X509 certificate.
+// return: a std::string of the DER encoding of the X509_NAME issuer name.
+absl::StatusOr<std::string> IssuerFromCert(X509* cert);
+
 }  // namespace grpc_core
 
 #endif  // GRPC_SRC_CORE_TSI_SSL_TRANSPORT_SECURITY_UTILS_H
diff --git a/src/python/grpcio/grpc/aio/_interceptor.py b/src/python/grpcio/grpc/aio/_interceptor.py
index 38312b7955b..e7ceb00fbbf 100644
--- a/src/python/grpcio/grpc/aio/_interceptor.py
+++ b/src/python/grpcio/grpc/aio/_interceptor.py
@@ -476,7 +476,7 @@ class _InterceptedStreamResponseMixin:
     _response_aiter: Optional[AsyncIterable[ResponseType]]
 
     def _init_stream_response_mixin(self) -> None:
-        # Is initalized later, otherwise if the iterator is not finnally
+        # Is initalized later, otherwise if the iterator is not finally
         # consumed a logging warning is emmited by Asyncio.
         self._response_aiter = None
 
diff --git a/test/core/security/BUILD b/test/core/security/BUILD
index 6b7f7bf4899..2899bc9f523 100644
--- a/test/core/security/BUILD
+++ b/test/core/security/BUILD
@@ -569,6 +569,7 @@ grpc_cc_test(
     srcs = ["grpc_tls_crl_provider_test.cc"],
     data = [
         "//test/core/tsi/test_creds/crl_data:ca.pem",
+        "//test/core/tsi/test_creds/crl_data:intermediate_ca.pem",
         "//test/core/tsi/test_creds/crl_data/crls:ab06acdd.r0",
         "//test/core/tsi/test_creds/crl_data/crls:b9322cac.r0",
         "//test/core/tsi/test_creds/crl_data/crls:current.crl",
@@ -585,6 +586,7 @@ grpc_cc_test(
         "//test/core/event_engine:event_engine_test_utils",
         "//test/core/event_engine/fuzzing_event_engine",
         "//test/core/event_engine/fuzzing_event_engine:fuzzing_event_engine_proto",
+        "//test/core/tsi:transport_security_test_lib",
         "//test/core/util:fuzz_config_vars_proto",
         "//test/core/util:grpc_test_util",
     ],
diff --git a/test/core/security/grpc_tls_crl_provider_test.cc b/test/core/security/grpc_tls_crl_provider_test.cc
index f47028b160b..76cc0bdf34d 100644
--- a/test/core/security/grpc_tls_crl_provider_test.cc
+++ b/test/core/security/grpc_tls_crl_provider_test.cc
@@ -40,16 +40,15 @@
 #include "test/core/event_engine/event_engine_test_utils.h"
 #include "test/core/event_engine/fuzzing_event_engine/fuzzing_event_engine.h"
 #include "test/core/event_engine/fuzzing_event_engine/fuzzing_event_engine.pb.h"
+#include "test/core/tsi/transport_security_test_lib.h"
 #include "test/core/util/test_config.h"
 #include "test/core/util/tls_utils.h"
 
 static constexpr absl::string_view kCrlPath =
     "test/core/tsi/test_creds/crl_data/crls/current.crl";
 static constexpr absl::string_view kCrlName = "current.crl";
-static constexpr absl::string_view kCrlIssuer =
-    "/C=AU/ST=Some-State/O=Internet Widgits Pty Ltd/CN=testca";
-static constexpr absl::string_view kCrlIntermediateIssuer =
-    "/CN=intermediatecert.example.com";
+static constexpr absl::string_view kCrlIntermediateIssuerPath =
+    "test/core/tsi/test_creds/crl_data/intermediate_ca.pem";
 static constexpr absl::string_view kCrlDirectory =
     "test/core/tsi/test_creds/crl_data/crls";
 static constexpr absl::string_view kRootCert =
@@ -88,9 +87,35 @@ class FakeDirectoryReader : public DirectoryReader {
       std::vector<std::string>();
 };
 
-class DirectoryReloaderCrlProviderTest : public ::testing::Test {
+class CrlProviderTest : public ::testing::Test {
  public:
   void SetUp() override {
+    std::string pem_cert = GetFileContents(kRootCert.data());
+    X509* issuer = ReadPemCert(pem_cert);
+    auto base_crl_issuer = IssuerFromCert(issuer);
+    ASSERT_EQ(base_crl_issuer.status(), absl::OkStatus());
+    base_crl_issuer_ = *base_crl_issuer;
+    std::string intermediate_string =
+        GetFileContents(kCrlIntermediateIssuerPath.data());
+    X509* intermediate_issuer = ReadPemCert(intermediate_string);
+    auto intermediate_crl_issuer = IssuerFromCert(intermediate_issuer);
+    ASSERT_EQ(intermediate_crl_issuer.status(), absl::OkStatus());
+    intermediate_crl_issuer_ = *intermediate_crl_issuer;
+    X509_free(issuer);
+    X509_free(intermediate_issuer);
+  }
+
+  void TearDown() override {}
+
+ protected:
+  std::string base_crl_issuer_;
+  std::string intermediate_crl_issuer_;
+};
+
+class DirectoryReloaderCrlProviderTest : public CrlProviderTest {
+ public:
+  void SetUp() override {
+    CrlProviderTest::SetUp();
     event_engine_ =
         std::make_shared<grpc_event_engine::experimental::FuzzingEventEngine>(
             grpc_event_engine::experimental::FuzzingEventEngine::Options(),
@@ -140,15 +165,15 @@ class DirectoryReloaderCrlProviderTest : public ::testing::Test {
       event_engine_;
 };
 
-TEST(CrlProviderTest, CanParseCrl) {
+TEST_F(CrlProviderTest, CanParseCrl) {
   std::string crl_string = GetFileContents(kCrlPath.data());
   absl::StatusOr<std::shared_ptr<Crl>> crl = Crl::Parse(crl_string);
   ASSERT_TRUE(crl.ok()) << crl.status();
   ASSERT_NE(*crl, nullptr);
-  EXPECT_EQ((*crl)->Issuer(), kCrlIssuer);
+  EXPECT_EQ((*crl)->Issuer(), base_crl_issuer_);
 }
 
-TEST(CrlProviderTest, InvalidFile) {
+TEST_F(CrlProviderTest, InvalidFile) {
   std::string crl_string = "INVALID CRL FILE";
   absl::StatusOr<std::shared_ptr<Crl>> crl = Crl::Parse(crl_string);
   EXPECT_EQ(crl.status(),
@@ -156,18 +181,18 @@ TEST(CrlProviderTest, InvalidFile) {
                 "Conversion from PEM string to X509 CRL failed."));
 }
 
-TEST(CrlProviderTest, StaticCrlProviderLookup) {
+TEST_F(CrlProviderTest, StaticCrlProviderLookup) {
   std::vector<std::string> crl_strings = {GetFileContents(kCrlPath.data())};
   absl::StatusOr<std::shared_ptr<CrlProvider>> provider =
       experimental::CreateStaticCrlProvider(crl_strings);
   ASSERT_TRUE(provider.ok()) << provider.status();
-  CertificateInfoImpl cert(kCrlIssuer);
+  CertificateInfoImpl cert(base_crl_issuer_);
   auto crl = (*provider)->GetCrl(cert);
   ASSERT_NE(crl, nullptr);
-  EXPECT_EQ(crl->Issuer(), kCrlIssuer);
+  EXPECT_EQ(crl->Issuer(), base_crl_issuer_);
 }
 
-TEST(CrlProviderTest, StaticCrlProviderLookupIssuerNotFound) {
+TEST_F(CrlProviderTest, StaticCrlProviderLookupIssuerNotFound) {
   std::vector<std::string> crl_strings = {GetFileContents(kCrlPath.data())};
   absl::StatusOr<std::shared_ptr<CrlProvider>> provider =
       experimental::CreateStaticCrlProvider(crl_strings);
@@ -181,14 +206,14 @@ TEST_F(DirectoryReloaderCrlProviderTest, CrlLookupGood) {
   auto provider =
       CreateCrlProvider(kCrlDirectory, std::chrono::seconds(60), nullptr);
   ASSERT_TRUE(provider.ok()) << provider.status();
-  CertificateInfoImpl cert(kCrlIssuer);
+  CertificateInfoImpl cert(base_crl_issuer_);
   auto crl = (*provider)->GetCrl(cert);
   ASSERT_NE(crl, nullptr);
-  EXPECT_EQ(crl->Issuer(), kCrlIssuer);
-  CertificateInfoImpl intermediate(kCrlIntermediateIssuer);
+  EXPECT_EQ(crl->Issuer(), base_crl_issuer_);
+  CertificateInfoImpl intermediate(intermediate_crl_issuer_);
   auto intermediate_crl = (*provider)->GetCrl(intermediate);
   ASSERT_NE(intermediate_crl, nullptr);
-  EXPECT_EQ(intermediate_crl->Issuer(), kCrlIntermediateIssuer);
+  EXPECT_EQ(intermediate_crl->Issuer(), intermediate_crl_issuer_);
 }
 
 TEST_F(DirectoryReloaderCrlProviderTest, CrlLookupMissingIssuer) {
@@ -204,7 +229,7 @@ TEST_F(DirectoryReloaderCrlProviderTest, ReloadsAndDeletes) {
   const std::chrono::seconds kRefreshDuration(60);
   auto provider = CreateCrlProvider(kRefreshDuration, nullptr);
   ASSERT_TRUE(provider.ok()) << provider.status();
-  CertificateInfoImpl cert(kCrlIssuer);
+  CertificateInfoImpl cert(base_crl_issuer_);
   auto should_be_no_crl = (*provider)->GetCrl(cert);
   ASSERT_EQ(should_be_no_crl, nullptr);
   // Give the provider files to find in the directory
@@ -212,7 +237,7 @@ TEST_F(DirectoryReloaderCrlProviderTest, ReloadsAndDeletes) {
   event_engine_->TickForDuration(kRefreshDuration);
   auto crl = (*provider)->GetCrl(cert);
   ASSERT_NE(crl, nullptr);
-  EXPECT_EQ(crl->Issuer(), kCrlIssuer);
+  EXPECT_EQ(crl->Issuer(), base_crl_issuer_);
   // Now we won't see any files in our directory
   directory_reader_->SetFilesInDirectory({});
   event_engine_->TickForDuration(kRefreshDuration);
@@ -229,10 +254,10 @@ TEST_F(DirectoryReloaderCrlProviderTest, WithCorruption) {
   auto provider =
       CreateCrlProvider(kRefreshDuration, std::move(reload_error_callback));
   ASSERT_TRUE(provider.ok()) << provider.status();
-  CertificateInfoImpl cert(kCrlIssuer);
+  CertificateInfoImpl cert(base_crl_issuer_);
   auto crl = (*provider)->GetCrl(cert);
   ASSERT_NE(crl, nullptr);
-  EXPECT_EQ(crl->Issuer(), kCrlIssuer);
+  EXPECT_EQ(crl->Issuer(), base_crl_issuer_);
   EXPECT_EQ(reload_errors.size(), 0);
   // Point the provider at a non-crl file so loading fails
   // Should result in the CRL Reloader keeping the old CRL data
@@ -240,7 +265,7 @@ TEST_F(DirectoryReloaderCrlProviderTest, WithCorruption) {
   event_engine_->TickForDuration(kRefreshDuration);
   auto crl_post_update = (*provider)->GetCrl(cert);
   ASSERT_NE(crl_post_update, nullptr);
-  EXPECT_EQ(crl_post_update->Issuer(), kCrlIssuer);
+  EXPECT_EQ(crl_post_update->Issuer(), base_crl_issuer_);
   EXPECT_EQ(reload_errors.size(), 1);
 }
 
diff --git a/test/core/tsi/BUILD b/test/core/tsi/BUILD
index 372ba9a3747..be8a6f3de82 100644
--- a/test/core/tsi/BUILD
+++ b/test/core/tsi/BUILD
@@ -64,12 +64,23 @@ grpc_cc_test(
 grpc_cc_test(
     name = "ssl_transport_security_utils_test",
     srcs = ["ssl_transport_security_utils_test.cc"],
+    data = [
+        "//test/core/tsi/test_creds/crl_data:ca.pem",
+        "//test/core/tsi/test_creds/crl_data:evil_ca.pem",
+        "//test/core/tsi/test_creds/crl_data:intermediate_ca.pem",
+        "//test/core/tsi/test_creds/crl_data:leaf_signed_by_intermediate.pem",
+        "//test/core/tsi/test_creds/crl_data/crls:current.crl",
+        "//test/core/tsi/test_creds/crl_data/crls:intermediate.crl",
+        "//test/core/tsi/test_creds/crl_data/crls:invalid_content.crl",
+        "//test/core/tsi/test_creds/crl_data/crls:invalid_signature.crl",
+    ],
     external_deps = ["gtest"],
     language = "C++",
     tags = ["no_windows"],
     deps = [
         "//:gpr",
         "//:grpc",
+        "//test/core/tsi:transport_security_test_lib",
         "//test/core/util:grpc_test_util",
     ],
 )
diff --git a/test/core/tsi/ssl_transport_security_utils_test.cc b/test/core/tsi/ssl_transport_security_utils_test.cc
index 00e14627a14..bf5466eae1a 100644
--- a/test/core/tsi/ssl_transport_security_utils_test.cc
+++ b/test/core/tsi/ssl_transport_security_utils_test.cc
@@ -25,6 +25,7 @@
 #include <openssl/bio.h>
 #include <openssl/crypto.h>
 #include <openssl/ssl.h>
+#include <openssl/x509.h>
 
 #include "absl/status/status.h"
 #include "absl/status/statusor.h"
@@ -32,13 +33,30 @@
 #include "absl/strings/str_cat.h"
 #include "absl/strings/string_view.h"
 
+#include "src/core/lib/gprpp/load_file.h"
+#include "src/core/lib/slice/slice.h"
 #include "src/core/tsi/transport_security.h"
 #include "src/core/tsi/transport_security_interface.h"
+#include "test/core/tsi/transport_security_test_lib.h"
 #include "test/core/util/test_config.h"
 
 namespace grpc_core {
 namespace testing {
 
+const char* kValidCrl = "test/core/tsi/test_creds/crl_data/crls/current.crl";
+const char* kCrlIssuer = "test/core/tsi/test_creds/crl_data/ca.pem";
+const char* kModifiedSignature =
+    "test/core/tsi/test_creds/crl_data/crls/invalid_signature.crl";
+const char* kModifiedContent =
+    "test/core/tsi/test_creds/crl_data/crls/invalid_content.crl";
+const char* kIntermediateCrl =
+    "test/core/tsi/test_creds/crl_data/crls/intermediate.crl";
+const char* kIntermediateCrlIssuer =
+    "test/core/tsi/test_creds/crl_data/intermediate_ca.pem";
+const char* kLeafCert =
+    "test/core/tsi/test_creds/crl_data/leaf_signed_by_intermediate.pem";
+const char* kEvilCa = "test/core/tsi/test_creds/crl_data/evil_ca.pem";
+
 using ::testing::ContainerEq;
 using ::testing::NotNull;
 using ::testing::TestWithParam;
@@ -316,8 +334,8 @@ TEST_P(FlowTest,
                                 &protected_output_frames_size),
             tsi_result::TSI_OK);
 
-  // If |GetParam().plaintext_size| is larger than the inner client_buffer size
-  // (kMaxPlaintextBytesPerTlsRecord), then |Protect| will copy up to
+  // If |GetParam().plaintext_size| is larger than the inner client_buffer
+  // size (kMaxPlaintextBytesPerTlsRecord), then |Protect| will copy up to
   // |kMaxPlaintextBytesPerTlsRecord| bytes and output the protected
   // frame. Otherwise we need to manually flush the copied data in order
   // to get the protected frame.
@@ -378,8 +396,8 @@ TEST_P(FlowTest,
                                 &protected_output_frames_size),
             tsi_result::TSI_OK);
 
-  // If |GetParam().plaintext_size| is larger than the inner server_buffer size
-  // (kMaxPlaintextBytesPerTlsRecord), then |Protect| will copy up to
+  // If |GetParam().plaintext_size| is larger than the inner server_buffer
+  // size (kMaxPlaintextBytesPerTlsRecord), then |Protect| will copy up to
   // |kMaxPlaintextBytesPerTlsRecord| bytes and output the protected
   // frame. Otherwise we need to manually flush the copied data in order
   // to get the protected frame.
@@ -429,6 +447,188 @@ INSTANTIATE_TEST_SUITE_P(FrameProtectorUtil, FlowTest,
 
 #endif  // OPENSSL_IS_BORINGSSL
 
+class CrlUtils : public ::testing::Test {
+ public:
+  static void SetUpTestSuite() {
+#if OPENSSL_VERSION_NUMBER >= 0x10100000
+    OPENSSL_init_ssl(/*opts=*/0, /*settings=*/nullptr);
+#else
+    SSL_library_init();
+    SSL_load_error_strings();
+    OpenSSL_add_all_algorithms();
+#endif
+  }
+
+  void SetUp() override {
+    absl::StatusOr<Slice> root_crl = LoadFile(kValidCrl, false);
+    ASSERT_EQ(root_crl.status(), absl::OkStatus()) << root_crl.status();
+    root_crl_ = ReadCrl(root_crl->as_string_view());
+    absl::StatusOr<Slice> intermediate_crl = LoadFile(kIntermediateCrl, false);
+    ASSERT_EQ(intermediate_crl.status(), absl::OkStatus())
+        << intermediate_crl.status();
+    intermediate_crl_ = ReadCrl(intermediate_crl->as_string_view());
+    absl::StatusOr<Slice> invalid_signature_crl =
+        LoadFile(kModifiedSignature, false);
+    ASSERT_EQ(invalid_signature_crl.status(), absl::OkStatus())
+        << invalid_signature_crl.status();
+    invalid_signature_crl_ = ReadCrl(invalid_signature_crl->as_string_view());
+
+    absl::StatusOr<Slice> root_ca = LoadFile(kCrlIssuer, false);
+    ASSERT_EQ(root_ca.status(), absl::OkStatus());
+    root_ca_ = ReadPemCert(root_ca->as_string_view());
+    absl::StatusOr<Slice> intermediate_ca =
+        LoadFile(kIntermediateCrlIssuer, false);
+    ASSERT_EQ(intermediate_ca.status(), absl::OkStatus());
+    intermediate_ca_ = ReadPemCert(intermediate_ca->as_string_view());
+    absl::StatusOr<Slice> leaf_cert = LoadFile(kLeafCert, false);
+    ASSERT_EQ(leaf_cert.status(), absl::OkStatus());
+    leaf_cert_ = ReadPemCert(leaf_cert->as_string_view());
+    absl::StatusOr<Slice> evil_ca = LoadFile(kEvilCa, false);
+    ASSERT_EQ(evil_ca.status(), absl::OkStatus());
+    evil_ca_ = ReadPemCert(evil_ca->as_string_view());
+  }
+
+  void TearDown() override {
+    X509_CRL_free(root_crl_);
+    X509_CRL_free(intermediate_crl_);
+    X509_CRL_free(invalid_signature_crl_);
+    X509_free(root_ca_);
+    X509_free(intermediate_ca_);
+    X509_free(leaf_cert_);
+    X509_free(evil_ca_);
+  }
+
+ protected:
+  X509_CRL* root_crl_;
+  X509_CRL* intermediate_crl_;
+  X509_CRL* invalid_signature_crl_;
+  X509* root_ca_;
+  X509* intermediate_ca_;
+  X509* leaf_cert_;
+  X509* evil_ca_;
+};
+
+TEST_F(CrlUtils, VerifySignatureValid) {
+  EXPECT_TRUE(VerifyCrlSignature(root_crl_, root_ca_));
+}
+
+TEST_F(CrlUtils, VerifySignatureIntermediateValid) {
+  EXPECT_TRUE(VerifyCrlSignature(intermediate_crl_, intermediate_ca_));
+}
+
+TEST_F(CrlUtils, VerifySignatureModifiedSignature) {
+  EXPECT_FALSE(VerifyCrlSignature(invalid_signature_crl_, root_ca_));
+}
+
+TEST_F(CrlUtils, VerifySignatureModifiedContent) {
+  absl::StatusOr<Slice> crl_slice = LoadFile(kModifiedContent, false);
+  ASSERT_EQ(crl_slice.status(), absl::OkStatus()) << crl_slice.status();
+  X509_CRL* crl = ReadCrl(crl_slice->as_string_view());
+  EXPECT_EQ(crl, nullptr);
+}
+
+TEST_F(CrlUtils, VerifySignatureWrongIssuer) {
+  EXPECT_FALSE(VerifyCrlSignature(root_crl_, intermediate_ca_));
+}
+
+TEST_F(CrlUtils, VerifySignatureWrongIssuer2) {
+  EXPECT_FALSE(VerifyCrlSignature(intermediate_crl_, root_ca_));
+}
+
+TEST_F(CrlUtils, VerifySignatureNullCrl) {
+  EXPECT_FALSE(VerifyCrlSignature(nullptr, root_ca_));
+}
+
+TEST_F(CrlUtils, VerifySignatureNullCert) {
+  EXPECT_FALSE(VerifyCrlSignature(intermediate_crl_, nullptr));
+}
+
+TEST_F(CrlUtils, VerifySignatureNullCrlAndCert) {
+  EXPECT_FALSE(VerifyCrlSignature(nullptr, nullptr));
+}
+
+TEST_F(CrlUtils, VerifyIssuerNamesMatch) {
+  EXPECT_TRUE(VerifyCrlCertIssuerNamesMatch(root_crl_, root_ca_));
+}
+
+TEST_F(CrlUtils, VerifyIssuerNamesDontMatch) {
+  EXPECT_FALSE(VerifyCrlCertIssuerNamesMatch(root_crl_, leaf_cert_));
+}
+
+TEST_F(CrlUtils, DuplicatedIssuerNamePassesButSignatureCheckFails) {
+  // The issuer names will match, but it should fail a signature check
+  EXPECT_TRUE(VerifyCrlCertIssuerNamesMatch(root_crl_, evil_ca_));
+  EXPECT_FALSE(VerifyCrlSignature(root_crl_, evil_ca_));
+}
+
+TEST_F(CrlUtils, VerifyIssuerNameNullCrl) {
+  EXPECT_FALSE(VerifyCrlCertIssuerNamesMatch(nullptr, root_ca_));
+}
+
+TEST_F(CrlUtils, VerifyIssuerNameNullCert) {
+  EXPECT_FALSE(VerifyCrlCertIssuerNamesMatch(intermediate_crl_, nullptr));
+}
+
+TEST_F(CrlUtils, VerifyIssuerNameNullCrlAndCert) {
+  EXPECT_FALSE(VerifyCrlCertIssuerNamesMatch(nullptr, nullptr));
+}
+
+TEST_F(CrlUtils, HasCrlSignBitExists) { EXPECT_TRUE(HasCrlSignBit(root_ca_)); }
+
+TEST_F(CrlUtils, HasCrlSignBitMissing) {
+  EXPECT_FALSE(HasCrlSignBit(leaf_cert_));
+}
+
+TEST_F(CrlUtils, HasCrlSignBitNullCert) {
+  EXPECT_FALSE(HasCrlSignBit(nullptr));
+}
+
+TEST_F(CrlUtils, IssuerFromIntermediateCert) {
+  auto issuer = IssuerFromCert(intermediate_ca_);
+  // Build the known name for comparison
+  unsigned char* buf = nullptr;
+  X509_NAME* expected_issuer_name = X509_NAME_new();
+  ASSERT_TRUE(
+      X509_NAME_add_entry_by_txt(expected_issuer_name, "C", MBSTRING_ASC,
+                                 (const unsigned char*)"AU", -1, -1, 0));
+  ASSERT_TRUE(X509_NAME_add_entry_by_txt(
+      expected_issuer_name, "ST", MBSTRING_ASC,
+      (const unsigned char*)"Some-State", -1, -1, 0));
+  ASSERT_TRUE(X509_NAME_add_entry_by_txt(
+      expected_issuer_name, "O", MBSTRING_ASC,
+      (const unsigned char*)"Internet Widgits Pty Ltd", -1, -1, 0));
+  ASSERT_TRUE(
+      X509_NAME_add_entry_by_txt(expected_issuer_name, "CN", MBSTRING_ASC,
+                                 (const unsigned char*)"testca", -1, -1, 0));
+  int len = i2d_X509_NAME(expected_issuer_name, &buf);
+  std::string expected_issuer_name_der(reinterpret_cast<char const*>(buf), len);
+  OPENSSL_free(buf);
+  X509_NAME_free(expected_issuer_name);
+  ASSERT_EQ(issuer.status(), absl::OkStatus());
+  EXPECT_EQ(*issuer, expected_issuer_name_der);
+}
+
+TEST_F(CrlUtils, IssuerFromLeaf) {
+  auto issuer = IssuerFromCert(leaf_cert_);
+  // Build the known name for comparison
+  unsigned char* buf = nullptr;
+  X509_NAME* expected_issuer_name = X509_NAME_new();
+  ASSERT_TRUE(X509_NAME_add_entry_by_txt(
+      expected_issuer_name, "CN", MBSTRING_ASC,
+      (const unsigned char*)"intermediatecert.example.com", -1, -1, 0));
+  int len = i2d_X509_NAME(expected_issuer_name, &buf);
+  std::string expected_issuer_name_der(reinterpret_cast<char const*>(buf), len);
+  OPENSSL_free(buf);
+  X509_NAME_free(expected_issuer_name);
+  ASSERT_EQ(issuer.status(), absl::OkStatus());
+  EXPECT_EQ(*issuer, expected_issuer_name_der);
+}
+
+TEST_F(CrlUtils, IssuerFromCertNull) {
+  auto issuer = IssuerFromCert(nullptr);
+  EXPECT_EQ(issuer.status().code(), absl::StatusCode::kInvalidArgument);
+}
+
 }  // namespace testing
 }  // namespace grpc_core
 
diff --git a/test/core/tsi/test_creds/crl_data/BUILD b/test/core/tsi/test_creds/crl_data/BUILD
index ae3e58f7f72..d079cd5a7f0 100644
--- a/test/core/tsi/test_creds/crl_data/BUILD
+++ b/test/core/tsi/test_creds/crl_data/BUILD
@@ -25,4 +25,5 @@ exports_files([
     "leaf_and_intermediate_chain.pem",
     "intermediate_ca.key",
     "intermediate_ca.pem",
+    "evil_ca.pem",
 ])
diff --git a/test/core/tsi/test_creds/crl_data/README b/test/core/tsi/test_creds/crl_data/README
index 80f3568e95a..d19258c9440 100644
--- a/test/core/tsi/test_creds/crl_data/README
+++ b/test/core/tsi/test_creds/crl_data/README
@@ -46,6 +46,11 @@ Generate a chain with a leaf cert signed by an intermediate CA and revoke the in
 
 Run `intermediate_gen.sh` from the `test/core/tsi/test_creds/crl_data` directory
 
+Generate a CA with the same issuer name but a different public key than the base CA
+----------------------------------------------------------------------------
+
+Run `evil_ca_gen.sh` from the `test/core/tsi/test_creds/crl_data` directory
+
 
 Clean up:
 ---------
diff --git a/test/core/tsi/test_creds/crl_data/crls/BUILD b/test/core/tsi/test_creds/crl_data/crls/BUILD
index 922d279aa6a..ecbaa82a9df 100644
--- a/test/core/tsi/test_creds/crl_data/crls/BUILD
+++ b/test/core/tsi/test_creds/crl_data/crls/BUILD
@@ -19,4 +19,6 @@ exports_files([
     "b9322cac.r0",
     "current.crl",
     "intermediate.crl",
+    "invalid_signature.crl",
+    "invalid_content.crl",
 ])
diff --git a/test/core/tsi/test_creds/crl_data/crls/invalid_content.crl b/test/core/tsi/test_creds/crl_data/crls/invalid_content.crl
new file mode 100644
index 00000000000..22d8b48f0a0
--- /dev/null
+++ b/test/core/tsi/test_creds/crl_data/crls/invalid_content.crl
@@ -0,0 +1,15 @@
+-----BEGIN X509 CRL-----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+-----END X509 CRL-----
diff --git a/test/core/tsi/test_creds/crl_data/crls/invalid_signature.crl b/test/core/tsi/test_creds/crl_data/crls/invalid_signature.crl
new file mode 100644
index 00000000000..2431949ce77
--- /dev/null
+++ b/test/core/tsi/test_creds/crl_data/crls/invalid_signature.crl
@@ -0,0 +1,15 @@
+-----BEGIN X509 CRL-----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+-----END X509 CRL-----
diff --git a/test/core/tsi/test_creds/crl_data/evil_ca.key b/test/core/tsi/test_creds/crl_data/evil_ca.key
new file mode 100644
index 00000000000..41614f98bc4
--- /dev/null
+++ b/test/core/tsi/test_creds/crl_data/evil_ca.key
@@ -0,0 +1,28 @@
+-----BEGIN PRIVATE KEY-----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+-----END PRIVATE KEY-----
diff --git a/test/core/tsi/test_creds/crl_data/evil_ca.pem b/test/core/tsi/test_creds/crl_data/evil_ca.pem
new file mode 100644
index 00000000000..6708690b1db
--- /dev/null
+++ b/test/core/tsi/test_creds/crl_data/evil_ca.pem
@@ -0,0 +1,21 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/test/core/tsi/test_creds/crl_data/evil_ca_gen.sh b/test/core/tsi/test_creds/crl_data/evil_ca_gen.sh
new file mode 100644
index 00000000000..31dec70057c
--- /dev/null
+++ b/test/core/tsi/test_creds/crl_data/evil_ca_gen.sh
@@ -0,0 +1,18 @@
+#!/bin/bash
+# Copyright 2024 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Generates a CA with the same issuer name as the good CA in this directory
+openssl req -x509 -new -newkey rsa:2048 -nodes -keyout evil_ca.key -out evil_ca.pem \
+  -config ca-openssl.cnf -days 3650 -extensions v3_req
diff --git a/test/core/tsi/test_creds/crl_data/intermediate_gen.sh b/test/core/tsi/test_creds/crl_data/intermediate_gen.sh
index dd9fa2b0473..4a3ec030726 100644
--- a/test/core/tsi/test_creds/crl_data/intermediate_gen.sh
+++ b/test/core/tsi/test_creds/crl_data/intermediate_gen.sh
@@ -62,11 +62,9 @@ cp "./intermediate_ca/intermediate.crl" ./crls
 cp current.crl ./crls/
 openssl rehash ./crls/
 
-mkdir crls_missing_intermediate
 cp current.crl ./crls_missing_intermediate/
 openssl rehash ./crls_missing_intermediate/
 
-mkdir crls_missing_root
 cp intermediate.crl ./crls_missing_root/
 openssl rehash ./crls_missing_root/
 
diff --git a/test/core/tsi/transport_security_test_lib.cc b/test/core/tsi/transport_security_test_lib.cc
index 811ecff0076..a0be6edf466 100644
--- a/test/core/tsi/transport_security_test_lib.cc
+++ b/test/core/tsi/transport_security_test_lib.cc
@@ -762,3 +762,27 @@ std::string GenerateSelfSignedCertificate(
   BN_free(n);
   return pem;
 }
+
+X509* ReadPemCert(absl::string_view pem_cert) {
+  BIO* cert_bio =
+      BIO_new_mem_buf(pem_cert.data(), static_cast<int>(pem_cert.size()));
+  // Errors on BIO
+  if (cert_bio == nullptr) {
+    return nullptr;
+  }
+  X509* cert = PEM_read_bio_X509(cert_bio, nullptr, nullptr, nullptr);
+  BIO_free(cert_bio);
+  return cert;
+}
+
+X509_CRL* ReadCrl(absl::string_view crl_pem) {
+  BIO* crl_bio =
+      BIO_new_mem_buf(crl_pem.data(), static_cast<int>(crl_pem.size()));
+  // Errors on BIO
+  if (crl_bio == nullptr) {
+    return nullptr;
+  }
+  X509_CRL* crl = PEM_read_bio_X509_CRL(crl_bio, nullptr, nullptr, nullptr);
+  BIO_free(crl_bio);
+  return crl;
+}
diff --git a/test/core/tsi/transport_security_test_lib.h b/test/core/tsi/transport_security_test_lib.h
index 69f07c1269c..6e3efec2bff 100644
--- a/test/core/tsi/transport_security_test_lib.h
+++ b/test/core/tsi/transport_security_test_lib.h
@@ -19,6 +19,8 @@
 #ifndef GRPC_TEST_CORE_TSI_TRANSPORT_SECURITY_TEST_LIB_H
 #define GRPC_TEST_CORE_TSI_TRANSPORT_SECURITY_TEST_LIB_H
 
+#include <openssl/x509v3.h>
+
 #include <grpc/support/sync.h>
 
 #include "src/core/tsi/transport_security_interface.h"
@@ -238,4 +240,10 @@ struct SelfSignedCertificateOptions {
 std::string GenerateSelfSignedCertificate(
     const SelfSignedCertificateOptions& options);
 
+// Returns the OpenSSL representation of a PEM cert.
+X509* ReadPemCert(absl::string_view pem_cert);
+
+// Returns the OpenSSL representation of a CRL.
+X509_CRL* ReadCrl(absl::string_view crl_pem);
+
 #endif  // GRPC_TEST_CORE_TSI_TRANSPORT_SECURITY_TEST_LIB_H

From 70af2c2fdaf2c3f102827fae869f14334b847ed6 Mon Sep 17 00:00:00 2001
From: Eugene Ostroukhov <eostroukhov@google.com>
Date: Mon, 26 Feb 2024 13:35:25 -0800
Subject: [PATCH 14/16] [xds] xDS client per data plane target (#35730)

Closes #35730

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35730 from eugeneo:tasks/multiple-xds-clients 30b459658ec1ddf62ba416741769fe49b585c333
PiperOrigin-RevId: 610511488
---
 src/core/ext/xds/xds_client_grpc.cc           |  43 ++++--
 src/core/ext/xds/xds_client_grpc.h            |  13 +-
 src/core/ext/xds/xds_server_config_fetcher.cc |   4 +-
 src/core/resolver/xds/xds_resolver.cc         |   3 +-
 test/cpp/end2end/xds/xds_core_end2end_test.cc | 132 ++++++++++--------
 test/cpp/end2end/xds/xds_csds_end2end_test.cc |  79 ++++++++++-
 test/cpp/end2end/xds/xds_end2end_test_lib.cc  |  11 +-
 7 files changed, 204 insertions(+), 81 deletions(-)

diff --git a/src/core/ext/xds/xds_client_grpc.cc b/src/core/ext/xds/xds_client_grpc.cc
index 720ea4208fb..d5e4447cc02 100644
--- a/src/core/ext/xds/xds_client_grpc.cc
+++ b/src/core/ext/xds/xds_client_grpc.cc
@@ -92,7 +92,9 @@ namespace {
 
 Mutex* g_mu = new Mutex;
 const grpc_channel_args* g_channel_args ABSL_GUARDED_BY(*g_mu) = nullptr;
-GrpcXdsClient* g_xds_client ABSL_GUARDED_BY(*g_mu) = nullptr;
+// Key bytes live in clients so they outlive the entries in this map
+NoDestruct<std::map<absl::string_view, GrpcXdsClient*>> g_xds_client_map
+    ABSL_GUARDED_BY(*g_mu);
 char* g_fallback_bootstrap_config ABSL_GUARDED_BY(*g_mu) = nullptr;
 
 }  // namespace
@@ -139,9 +141,9 @@ absl::StatusOr<std::string> GetBootstrapContents(const char* fallback_config) {
 std::vector<RefCountedPtr<GrpcXdsClient>> GetAllXdsClients() {
   MutexLock lock(g_mu);
   std::vector<RefCountedPtr<GrpcXdsClient>> xds_clients;
-  if (g_xds_client != nullptr) {
+  for (const auto& key_client : *g_xds_client_map) {
     auto xds_client =
-        g_xds_client->RefIfNonZero(DEBUG_LOCATION, "DumpAllClientConfigs");
+        key_client.second->RefIfNonZero(DEBUG_LOCATION, "DumpAllClientConfigs");
     if (xds_client != nullptr) {
       xds_clients.emplace_back(xds_client.TakeAsSubclass<GrpcXdsClient>());
     }
@@ -152,7 +154,7 @@ std::vector<RefCountedPtr<GrpcXdsClient>> GetAllXdsClients() {
 }  // namespace
 
 absl::StatusOr<RefCountedPtr<GrpcXdsClient>> GrpcXdsClient::GetOrCreate(
-    const ChannelArgs& args, const char* reason) {
+    absl::string_view key, const ChannelArgs& args, const char* reason) {
   // If getting bootstrap from channel args, create a local XdsClient
   // instance for the channel or server instead of using the global instance.
   absl::optional<absl::string_view> bootstrap_config = args.GetString(
@@ -164,13 +166,14 @@ absl::StatusOr<RefCountedPtr<GrpcXdsClient>> GrpcXdsClient::GetOrCreate(
         GRPC_ARG_TEST_ONLY_DO_NOT_USE_IN_PROD_XDS_CLIENT_CHANNEL_ARGS);
     auto channel_args = ChannelArgs::FromC(xds_channel_args);
     return MakeRefCounted<GrpcXdsClient>(
-        std::move(*bootstrap), channel_args,
+        key, std::move(*bootstrap), channel_args,
         MakeOrphanable<GrpcXdsTransportFactory>(channel_args));
   }
   // Otherwise, use the global instance.
   MutexLock lock(g_mu);
-  if (g_xds_client != nullptr) {
-    auto xds_client = g_xds_client->RefIfNonZero(DEBUG_LOCATION, reason);
+  auto it = g_xds_client_map->find(key);
+  if (it != g_xds_client_map->end()) {
+    auto xds_client = it->second->RefIfNonZero(DEBUG_LOCATION, reason);
     if (xds_client != nullptr) {
       return xds_client.TakeAsSubclass<GrpcXdsClient>();
     }
@@ -188,9 +191,13 @@ absl::StatusOr<RefCountedPtr<GrpcXdsClient>> GrpcXdsClient::GetOrCreate(
   // Instantiate XdsClient.
   auto channel_args = ChannelArgs::FromC(g_channel_args);
   auto xds_client = MakeRefCounted<GrpcXdsClient>(
-      std::move(*bootstrap), channel_args,
+      key, std::move(*bootstrap), channel_args,
       MakeOrphanable<GrpcXdsTransportFactory>(channel_args));
-  g_xds_client = xds_client.get();
+  g_xds_client_map->emplace(xds_client->key(), xds_client.get());
+  if (GRPC_TRACE_FLAG_ENABLED(grpc_xds_client_trace)) {
+    gpr_log(GPR_INFO, "xDS client for key: %s was created",
+            std::string(key).c_str());
+  }
   return xds_client;
 }
 
@@ -211,6 +218,8 @@ grpc_slice GrpcXdsClient::DumpAllClientConfigs()
                                                                 arena.ptr());
     xds_client->mu()->Lock();
     xds_client->DumpClientConfig(&string_pool, arena.ptr(), client_config);
+    envoy_service_status_v3_ClientConfig_set_client_scope(
+        client_config, StdStringToUpbString(xds_client->key()));
   }
   // Serialize the upb message to bytes
   size_t output_length;
@@ -223,7 +232,8 @@ grpc_slice GrpcXdsClient::DumpAllClientConfigs()
 }
 
 GrpcXdsClient::GrpcXdsClient(
-    std::unique_ptr<GrpcXdsBootstrap> bootstrap, const ChannelArgs& args,
+    absl::string_view key, std::unique_ptr<GrpcXdsBootstrap> bootstrap,
+    const ChannelArgs& args,
     OrphanablePtr<XdsTransportFactory> transport_factory)
     : XdsClient(
           std::move(bootstrap), std::move(transport_factory),
@@ -237,13 +247,18 @@ GrpcXdsClient::GrpcXdsClient(
                    args.GetDurationFromIntMillis(
                            GRPC_ARG_XDS_RESOURCE_DOES_NOT_EXIST_TIMEOUT_MS)
                        .value_or(Duration::Seconds(15)))),
+      key_(key),
       certificate_provider_store_(MakeOrphanable<CertificateProviderStore>(
           static_cast<const GrpcXdsBootstrap&>(this->bootstrap())
               .certificate_providers())) {}
 
-GrpcXdsClient::~GrpcXdsClient() {
+void GrpcXdsClient::Orphan() {
   MutexLock lock(g_mu);
-  if (g_xds_client == this) g_xds_client = nullptr;
+  auto it = g_xds_client_map->find(key_);
+  if (it != g_xds_client_map->end() && it->second == this) {
+    g_xds_client_map->erase(it);
+  }
+  XdsClient::Orphan();
 }
 
 grpc_pollset_set* GrpcXdsClient::interested_parties() const {
@@ -258,9 +273,9 @@ void SetXdsChannelArgsForTest(grpc_channel_args* args) {
   g_channel_args = args;
 }
 
-void UnsetGlobalXdsClientForTest() {
+void UnsetGlobalXdsClientsForTest() {
   MutexLock lock(g_mu);
-  g_xds_client = nullptr;
+  g_xds_client_map->clear();
 }
 
 void SetXdsFallbackBootstrapConfig(const char* config) {
diff --git a/src/core/ext/xds/xds_client_grpc.h b/src/core/ext/xds/xds_client_grpc.h
index 7093ec4017b..72df525ab6e 100644
--- a/src/core/ext/xds/xds_client_grpc.h
+++ b/src/core/ext/xds/xds_client_grpc.h
@@ -43,7 +43,7 @@ class GrpcXdsClient : public XdsClient {
  public:
   // Factory function to get or create the global XdsClient instance.
   static absl::StatusOr<RefCountedPtr<GrpcXdsClient>> GetOrCreate(
-      const ChannelArgs& args, const char* reason);
+      absl::string_view key, const ChannelArgs& args, const char* reason);
 
   // Builds ClientStatusResponse containing all resources from all XdsClients
   static grpc_slice DumpAllClientConfigs();
@@ -60,10 +60,12 @@ class GrpcXdsClient : public XdsClient {
   // work for callers that use interested_parties() but not for callers
   // that also use certificate_provider_store(), but we should consider
   // alternatives for that case as well.
-  GrpcXdsClient(std::unique_ptr<GrpcXdsBootstrap> bootstrap,
+  GrpcXdsClient(absl::string_view key,
+                std::unique_ptr<GrpcXdsBootstrap> bootstrap,
                 const ChannelArgs& args,
                 OrphanablePtr<XdsTransportFactory> transport_factory);
-  ~GrpcXdsClient() override;
+
+  void Orphan() override;
 
   // Helpers for encoding the XdsClient object in channel args.
   static absl::string_view ChannelArgName() {
@@ -79,13 +81,16 @@ class GrpcXdsClient : public XdsClient {
     return *certificate_provider_store_;
   }
 
+  absl::string_view key() const { return key_; }
+
  private:
+  std::string key_;
   OrphanablePtr<CertificateProviderStore> certificate_provider_store_;
 };
 
 namespace internal {
 void SetXdsChannelArgsForTest(grpc_channel_args* args);
-void UnsetGlobalXdsClientForTest();
+void UnsetGlobalXdsClientsForTest();
 // Sets bootstrap config to be used when no env var is set.
 // Does not take ownership of config.
 void SetXdsFallbackBootstrapConfig(const char* config);
diff --git a/src/core/ext/xds/xds_server_config_fetcher.cc b/src/core/ext/xds/xds_server_config_fetcher.cc
index b996a7b56d8..6e406843a64 100644
--- a/src/core/ext/xds/xds_server_config_fetcher.cc
+++ b/src/core/ext/xds/xds_server_config_fetcher.cc
@@ -94,6 +94,8 @@ namespace {
 
 using ReadDelayHandle = XdsClient::ReadDelayHandle;
 
+constexpr absl::string_view kServerXdsClientKey = "#server";
+
 TraceFlag grpc_xds_server_config_fetcher_trace(false,
                                                "xds_server_config_fetcher");
 
@@ -1372,7 +1374,7 @@ grpc_server_config_fetcher* grpc_server_config_fetcher_xds_create(
       "update=%p, user_data=%p}, args=%p)",
       3, (notifier.on_serving_status_update, notifier.user_data, args));
   auto xds_client = grpc_core::GrpcXdsClient::GetOrCreate(
-      channel_args, "XdsServerConfigFetcher");
+      grpc_core::kServerXdsClientKey, channel_args, "XdsServerConfigFetcher");
   if (!xds_client.ok()) {
     gpr_log(GPR_ERROR, "Failed to create xds client: %s",
             xds_client.status().ToString().c_str());
diff --git a/src/core/resolver/xds/xds_resolver.cc b/src/core/resolver/xds/xds_resolver.cc
index ce2f33482dd..39f7688a219 100644
--- a/src/core/resolver/xds/xds_resolver.cc
+++ b/src/core/resolver/xds/xds_resolver.cc
@@ -880,7 +880,8 @@ void XdsResolver::ClusterSelectionFilter::Call::OnClientInitialMetadata(
 //
 
 void XdsResolver::StartLocked() {
-  auto xds_client = GrpcXdsClient::GetOrCreate(args_, "xds resolver");
+  auto xds_client =
+      GrpcXdsClient::GetOrCreate(uri_.ToString(), args_, "xds resolver");
   if (!xds_client.ok()) {
     gpr_log(GPR_ERROR,
             "Failed to create xds client -- channel will remain in "
diff --git a/test/cpp/end2end/xds/xds_core_end2end_test.cc b/test/cpp/end2end/xds/xds_core_end2end_test.cc
index 4f4f792affd..a0afbaaec82 100644
--- a/test/cpp/end2end/xds/xds_core_end2end_test.cc
+++ b/test/cpp/end2end/xds/xds_core_end2end_test.cc
@@ -13,8 +13,10 @@
 // limitations under the License.
 //
 
+#include <algorithm>
 #include <memory>
 #include <string>
+#include <type_traits>
 #include <vector>
 
 #include <gmock/gmock.h>
@@ -24,9 +26,11 @@
 
 #include "src/core/client_channel/backup_poller.h"
 #include "src/core/lib/config/config_vars.h"
+#include "src/proto/grpc/testing/xds/v3/listener.pb.h"
 #include "test/core/util/resolve_localhost_ip46.h"
 #include "test/core/util/scoped_env_var.h"
 #include "test/cpp/end2end/xds/xds_end2end_test_lib.h"
+#include "test/cpp/end2end/xds/xds_server.h"
 
 namespace grpc {
 namespace testing {
@@ -167,7 +171,21 @@ INSTANTIATE_TEST_SUITE_P(XdsTest, GlobalXdsClientTest,
                              XdsTestType::kBootstrapFromEnvVar)),
                          &XdsTestType::Name);
 
-TEST_P(GlobalXdsClientTest, MultipleChannelsShareXdsClient) {
+TEST_P(GlobalXdsClientTest, MultipleChannelsSameTargetShareXdsClient) {
+  CreateAndStartBackends(1);
+  EdsResourceArgs args({{"locality0", CreateEndpointsForBackends()}});
+  balancer_->ads_service()->SetEdsResource(BuildEdsResource(args));
+  WaitForAllBackends(DEBUG_LOCATION);
+  // Create second channel and tell it to connect to the same server.
+  auto channel2 = CreateChannel(/*failover_timeout_ms=*/0, kServerName);
+  channel2->GetState(/*try_to_connect=*/true);
+  ASSERT_TRUE(channel2->WaitForConnected(grpc_timeout_seconds_to_deadline(1)));
+  // Make sure there's only one client connected.
+  EXPECT_EQ(1UL, balancer_->ads_service()->clients().size());
+}
+
+TEST_P(GlobalXdsClientTest,
+       MultipleChannelsDifferentTargetDoNotShareXdsClient) {
   CreateAndStartBackends(1);
   const char* kNewServerName = "new-server.example.com";
   Listener listener = default_listener_;
@@ -181,8 +199,8 @@ TEST_P(GlobalXdsClientTest, MultipleChannelsShareXdsClient) {
   auto channel2 = CreateChannel(/*failover_timeout_ms=*/0, kNewServerName);
   channel2->GetState(/*try_to_connect=*/true);
   ASSERT_TRUE(channel2->WaitForConnected(grpc_timeout_seconds_to_deadline(1)));
-  // Make sure there's only one client connected.
-  EXPECT_EQ(1UL, balancer_->ads_service()->clients().size());
+  // Make sure there are two clients connected.
+  EXPECT_EQ(2UL, balancer_->ads_service()->clients().size());
 }
 
 TEST_P(
@@ -219,64 +237,62 @@ TEST_P(
 }
 
 // Tests that the NACK for multiple bad LDS resources includes both errors.
-// This needs to be in GlobalXdsClientTest because the only way to request
-// two LDS resources in the same XdsClient is for two channels to share
-// the same XdsClient.
+// This needs to use xDS server as this is the only scenario when XdsClient
+// is shared.
 TEST_P(GlobalXdsClientTest, MultipleBadLdsResources) {
-  CreateAndStartBackends(1);
-  constexpr char kServerName2[] = "server.other.com";
-  constexpr char kServerName3[] = "server.another.com";
-  auto listener = default_listener_;
-  listener.clear_api_listener();
-  balancer_->ads_service()->SetLdsResource(listener);
-  listener.set_name(kServerName2);
-  balancer_->ads_service()->SetLdsResource(listener);
-  listener = default_listener_;
-  listener.set_name(kServerName3);
-  SetListenerAndRouteConfiguration(balancer_.get(), listener,
-                                   default_route_config_);
-  EdsResourceArgs args({{"locality0", CreateEndpointsForBackends()}});
+  CreateBackends(2, true);
+  EdsResourceArgs args({{"locality0", CreateEndpointsForBackends(0, 2)}});
   balancer_->ads_service()->SetEdsResource(BuildEdsResource(args));
-  const auto response_state = WaitForLdsNack(DEBUG_LOCATION);
+  auto listener = default_server_listener_;
+  listener.clear_address();
+  listener.set_name(GetServerListenerName(backends_[0]->port()));
+  balancer_->ads_service()->SetLdsResource(listener);
+  backends_[0]->Start();
+  auto response_state = WaitForLdsNack(DEBUG_LOCATION);
   ASSERT_TRUE(response_state.has_value()) << "timed out waiting for NACK";
-  EXPECT_EQ(response_state->error_message,
-            "xDS response validation errors: ["
-            "resource index 0: server.example.com: "
-            "INVALID_ARGUMENT: Listener has neither address nor ApiListener]");
-  // Need to create a second channel to subscribe to a second LDS resource.
-  auto channel2 = CreateChannel(0, kServerName2);
-  auto stub2 = grpc::testing::EchoTestService::NewStub(channel2);
-  {
-    ClientContext context;
-    EchoRequest request;
-    request.set_message(kRequestMessage);
-    EchoResponse response;
-    grpc::Status status = stub2->Echo(&context, request, &response);
-    EXPECT_FALSE(status.ok());
-    // Wait for second NACK to be reported to xDS server.
-    const auto response_state = WaitForLdsNack(DEBUG_LOCATION);
-    ASSERT_TRUE(response_state.has_value()) << "timed out waiting for NACK";
-    EXPECT_EQ(
-        response_state->error_message,
-        "xDS response validation errors: ["
-        "resource index 0: server.other.com: "
-        "INVALID_ARGUMENT: Listener has neither address nor ApiListener; "
-        "resource index 1: server.example.com: "
-        "INVALID_ARGUMENT: Listener has neither address nor ApiListener]");
-  }
-  // Now start a new channel with a third server name, this one with a
-  // valid resource.
-  auto channel3 = CreateChannel(0, kServerName3);
-  auto stub3 = grpc::testing::EchoTestService::NewStub(channel3);
-  {
-    ClientContext context;
-    EchoRequest request;
-    request.set_message(kRequestMessage);
-    EchoResponse response;
-    grpc::Status status = stub3->Echo(&context, request, &response);
-    EXPECT_TRUE(status.ok()) << "code=" << status.error_code()
-                             << " message=" << status.error_message();
-  }
+  EXPECT_EQ(
+      response_state->error_message,
+      absl::StrFormat(
+          "xDS response validation errors: ["
+          "resource index 0: "
+          "grpc/server?xds.resource.listening_address=127.0.0.1:%lu: "
+          "INVALID_ARGUMENT: Listener has neither address nor ApiListener]",
+          backends_[0]->port()));
+  listener = default_server_listener_;
+  listener.clear_address();
+  listener.set_name(GetServerListenerName(backends_[1]->port()));
+  balancer_->ads_service()->SetLdsResource(listener);
+  backends_[1]->Start();
+  constexpr absl::string_view kMessageFormat =
+      "xDS response validation errors: ["
+      "resource index 0: "
+      "grpc/server?xds.resource.listening_address=127.0.0.1:%d: "
+      "INVALID_ARGUMENT: Listener has neither address nor "
+      "ApiListener; "
+      "resource index 1: "
+      "grpc/server?xds.resource.listening_address=127.0.0.1:%d: "
+      "INVALID_ARGUMENT: Listener has neither address nor "
+      "ApiListener"
+      "]";
+  const std::string expected_message1 = absl::StrFormat(
+      kMessageFormat, backends_[0]->port(), backends_[1]->port());
+  const std::string expected_message2 = absl::StrFormat(
+      kMessageFormat, backends_[1]->port(), backends_[0]->port());
+  response_state = WaitForNack(
+      DEBUG_LOCATION, [&]() -> absl::optional<AdsServiceImpl::ResponseState> {
+        auto response = balancer_->ads_service()->lds_response_state();
+        if (response.has_value() &&
+            response->state == AdsServiceImpl::ResponseState::NACKED) {
+          if (response->error_message == expected_message1 ||
+              response->error_message == expected_message2) {
+            return response;
+          }
+          gpr_log(GPR_INFO, "non-matching NACK message: %s",
+                  response->error_message.c_str());
+        }
+        return absl::nullopt;
+      });
+  EXPECT_TRUE(response_state.has_value()) << "timed out waiting for NACK";
 }
 
 // Tests that we don't trigger does-not-exist callbacks for a resource
diff --git a/test/cpp/end2end/xds/xds_csds_end2end_test.cc b/test/cpp/end2end/xds/xds_csds_end2end_test.cc
index 117e5555285..cde8148b9c5 100644
--- a/test/cpp/end2end/xds/xds_csds_end2end_test.cc
+++ b/test/cpp/end2end/xds/xds_csds_end2end_test.cc
@@ -22,6 +22,7 @@
 
 #include "absl/memory/memory.h"
 #include "absl/strings/str_cat.h"
+#include "absl/strings/strip.h"
 
 #include <grpcpp/create_channel.h>
 #include <grpcpp/security/credentials.h>
@@ -344,7 +345,7 @@ TEST_P(ClientStatusDiscoveryServiceTest, XdsConfigDumpVanilla) {
   // Fetches the client config
   auto csds_response = FetchCsdsResponse();
   gpr_log(GPR_INFO, "xDS config dump: %s", csds_response.DebugString().c_str());
-  EXPECT_EQ(1, csds_response.config_size());
+  ASSERT_EQ(1, csds_response.config_size());
   const auto& client_config = csds_response.config(0);
   // Validate the Node information
   EXPECT_THAT(client_config.node(),
@@ -615,6 +616,82 @@ TEST_P(ClientStatusDiscoveryServiceTest, XdsConfigDumpClusterRequested) {
                       ClientResourceStatus::REQUESTED, ::testing::_))));
 }
 
+TEST_P(ClientStatusDiscoveryServiceTest, XdsConfigDumpMultiClient) {
+  Listener listener = default_listener_;
+  const char* kServer2Name = "server2.example.com";
+  listener.set_name(kServer2Name);
+  balancer_->ads_service()->SetLdsResource(listener);
+  SetListenerAndRouteConfiguration(balancer_.get(), listener,
+                                   default_route_config_);
+  CreateAndStartBackends(1);
+  const size_t kNumRpcs = 5;
+  EdsResourceArgs args({{"locality0", CreateEndpointsForBackends(0, 1)}});
+  balancer_->ads_service()->SetEdsResource(BuildEdsResource(args));
+  // Send several RPCs to ensure the xDS setup works
+  CheckRpcSendOk(DEBUG_LOCATION, kNumRpcs);
+  // Connect to a second server
+  auto channel2 = CreateChannel(0, kServer2Name);
+  channel2->GetState(/*try_to_connect=*/true);
+  ASSERT_TRUE(channel2->WaitForConnected(grpc_timeout_seconds_to_deadline(1)));
+  // Fetches the client config
+  auto csds_response = FetchCsdsResponse();
+  ASSERT_EQ(2, csds_response.config_size());
+  std::vector<std::string> scopes;
+  for (const auto& client_config : csds_response.config()) {
+    // Validate the Node information
+    EXPECT_THAT(client_config.node(),
+                EqNode("xds_end2end_test", ::testing::HasSubstr("C-core"),
+                       ::testing::HasSubstr(grpc_version_string()),
+                       ::testing::ElementsAre(
+                           "envoy.lb.does_not_support_overprovisioning")));
+    scopes.emplace_back(client_config.client_scope());
+    absl::string_view server = client_config.client_scope();
+    // Listener matcher depends on whether RDS is enabled.
+    ::testing::Matcher<google::protobuf::Any> api_listener_matcher;
+    if (GetParam().enable_rds_testing()) {
+      api_listener_matcher = IsRdsEnabledHCM();
+    } else {
+      api_listener_matcher =
+          EqNoRdsHCM(kDefaultRouteConfigurationName, kDefaultClusterName);
+    }
+    // Construct list of all matchers.
+    std::vector<::testing::Matcher<
+        envoy::service::status::v3::ClientConfig_GenericXdsConfig>>
+        matchers = {
+            // Listener
+            EqGenericXdsConfig(
+                kLdsTypeUrl, absl::StripPrefix(server, "xds:"), "3",
+                UnpackListener(EqListener(absl::StripPrefix(server, "xds:"),
+                                          api_listener_matcher)),
+                ClientResourceStatus::ACKED, ::testing::_),
+            // Cluster
+            EqGenericXdsConfig(kCdsTypeUrl, kDefaultClusterName, "1",
+                               UnpackCluster(EqCluster(kDefaultClusterName)),
+                               ClientResourceStatus::ACKED, ::testing::_),
+            // ClusterLoadAssignment
+            EqGenericXdsConfig(
+                kEdsTypeUrl, kDefaultEdsServiceName, "1",
+                UnpackClusterLoadAssignment(EqClusterLoadAssignment(
+                    kDefaultEdsServiceName, backends_[0]->port(),
+                    kDefaultLocalityWeight)),
+                ClientResourceStatus::ACKED, ::testing::_),
+        };
+    // If RDS is enabled, add matcher for RDS resource.
+    if (GetParam().enable_rds_testing()) {
+      matchers.push_back(EqGenericXdsConfig(
+          kRdsTypeUrl, kDefaultRouteConfigurationName, "2",
+          UnpackRouteConfiguration(EqRouteConfiguration(
+              kDefaultRouteConfigurationName, kDefaultClusterName)),
+          ClientResourceStatus::ACKED, ::testing::_));
+    }
+    // Validate the dumped xDS configs
+    EXPECT_THAT(client_config.generic_xds_configs(),
+                ::testing::UnorderedElementsAreArray(matchers));
+  }
+  EXPECT_THAT(scopes, ::testing::UnorderedElementsAre(
+                          "xds:server.example.com", "xds:server2.example.com"));
+}
+
 class CsdsShortAdsTimeoutTest : public ClientStatusDiscoveryServiceTest {
  protected:
   void SetUp() override {
diff --git a/test/cpp/end2end/xds/xds_end2end_test_lib.cc b/test/cpp/end2end/xds/xds_end2end_test_lib.cc
index b95d91a1dd9..c398694266f 100644
--- a/test/cpp/end2end/xds/xds_end2end_test_lib.cc
+++ b/test/cpp/end2end/xds/xds_end2end_test_lib.cc
@@ -523,7 +523,7 @@ void XdsEnd2endTest::InitClient(XdsBootstrapBuilder builder,
     // because it's not expecting the client to connect.  It also
     // ensures that each test can independently set the global channel
     // args for the xDS channel.
-    grpc_core::internal::UnsetGlobalXdsClientForTest();
+    grpc_core::internal::UnsetGlobalXdsClientsForTest();
   }
   // Create channel and stub.
   ResetStub();
@@ -558,7 +558,14 @@ std::shared_ptr<Channel> XdsEnd2endTest::CreateChannel(
         GRPC_ARG_TEST_ONLY_DO_NOT_USE_IN_PROD_XDS_CLIENT_CHANNEL_ARGS,
         &xds_channel_args_, &kChannelArgsArgVtable);
   }
-  std::string uri = absl::StrCat("xds://", xds_authority, "/", server_name);
+  std::vector<absl::string_view> parts = {"xds:"};
+  if (xds_authority != nullptr && xds_authority[0] != '\0') {
+    parts.emplace_back("//");
+    parts.emplace_back(xds_authority);
+    parts.emplace_back("/");
+  }
+  parts.emplace_back(server_name);
+  std::string uri = absl::StrJoin(parts, "");
   std::shared_ptr<ChannelCredentials> channel_creds =
       GetParam().use_xds_credentials()
           ? XdsCredentials(CreateTlsFallbackCredentials())

From 8b4079f4dd48a836adbc62e194d07048f6f7f7b5 Mon Sep 17 00:00:00 2001
From: Yash Tibrewal <yashkt@google.com>
Date: Mon, 26 Feb 2024 13:48:51 -0800
Subject: [PATCH 15/16] [shutdown] Add logs when shutdown is done (#36002)

Needed for some shutdown debugging. I was thinking whether to use `fprintf` to stderr directly instead of using `gpr_log`, the reason being that grpc has shutdown and it may be bad to use `gpr_log` after shutdown. Currently atleast, we do not modify the `gpr_log` function on `init`/`shutdown` so it seems fine to continue using it. Additionally, given that this is just for own internal debugging purposes, I don't want to sprinkle `fprintf` around if it's not necessary.

Closes #36002

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/36002 from yashykt:LogOnGrpcShutdown 61b9ad573aafceafed790beb1c6e6b065911ecf0
PiperOrigin-RevId: 610515417
---
 src/core/lib/surface/init.cc | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/core/lib/surface/init.cc b/src/core/lib/surface/init.cc
index 25ba6fb97cf..276bf5600ee 100644
--- a/src/core/lib/surface/init.cc
+++ b/src/core/lib/surface/init.cc
@@ -136,8 +136,8 @@ void grpc_shutdown_internal_locked(void)
   g_shutting_down_cv->SignalAll();
 }
 
-void grpc_shutdown_internal(void* /*ignored*/) {
-  GRPC_API_TRACE("grpc_shutdown_internal", 0, ());
+void grpc_shutdown_from_cleanup_thread(void* /*ignored*/) {
+  GRPC_API_TRACE("grpc_shutdown_from_cleanup_thread", 0, ());
   grpc_core::MutexLock lock(g_init_mu);
   // We have released lock from the shutdown thread and it is possible that
   // another grpc_init has been called, and do nothing if that is the case.
@@ -145,6 +145,7 @@ void grpc_shutdown_internal(void* /*ignored*/) {
     return;
   }
   grpc_shutdown_internal_locked();
+  gpr_log(GPR_DEBUG, "grpc_shutdown from cleanup thread done");
 }
 
 void grpc_shutdown(void) {
@@ -165,6 +166,7 @@ void grpc_shutdown(void) {
       gpr_log(GPR_DEBUG, "grpc_shutdown starts clean-up now");
       g_shutting_down = true;
       grpc_shutdown_internal_locked();
+      gpr_log(GPR_DEBUG, "grpc_shutdown done");
     } else {
       // spawn a detached thread to do the actual clean up in case we are
       // currently in an executor thread.
@@ -172,7 +174,7 @@ void grpc_shutdown(void) {
       g_initializations++;
       g_shutting_down = true;
       grpc_core::Thread cleanup_thread(
-          "grpc_shutdown", grpc_shutdown_internal, nullptr, nullptr,
+          "grpc_shutdown", grpc_shutdown_from_cleanup_thread, nullptr, nullptr,
           grpc_core::Thread::Options().set_joinable(false).set_tracked(false));
       cleanup_thread.Start();
     }

From 7acea32fc456e53efe18b506a0eb326f0fa9e700 Mon Sep 17 00:00:00 2001
From: "Mark D. Roth" <roth@google.com>
Date: Tue, 27 Feb 2024 01:09:28 +0000
Subject: [PATCH 16/16] fix test

---
 test/cpp/end2end/xds/xds_wrr_end2end_test.cc | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/test/cpp/end2end/xds/xds_wrr_end2end_test.cc b/test/cpp/end2end/xds/xds_wrr_end2end_test.cc
index ad9036bdf10..16799140b8a 100644
--- a/test/cpp/end2end/xds/xds_wrr_end2end_test.cc
+++ b/test/cpp/end2end/xds/xds_wrr_end2end_test.cc
@@ -113,7 +113,7 @@ TEST_P(WrrTest, MetricsHaveLocalityLabel) {
       grpc_core::GlobalInstrumentsRegistryTestPeer::
           FindDoubleHistogramHandleByName("grpc.lb.wrr.endpoint_weights")
               .value();
-  const std::string target = absl::StrCat("xds:///", kServerName);
+  const std::string target = absl::StrCat("xds:", kServerName);
   const absl::string_view kLabelValues[] = {/*target=*/target};
   // Register stats plugin before initializing client.
   auto stats_plugin = grpc_core::FakeStatsPluginBuilder()
@@ -137,10 +137,7 @@ TEST_P(WrrTest, MetricsHaveLocalityLabel) {
   EdsResourceArgs args({{"locality0", CreateEndpointsForBackends(0, 1)},
                         {"locality1", CreateEndpointsForBackends(1, 2)}});
   balancer_->ads_service()->SetEdsResource(BuildEdsResource(args));
-  CheckRpcSendOk(DEBUG_LOCATION, 10);
-  // Both backends got some requests.  The exact count doesn't matter.
-  EXPECT_GT(backends_[0]->backend_service()->request_count(), 0);
-  EXPECT_GT(backends_[1]->backend_service()->request_count(), 0);
+  WaitForAllBackends(DEBUG_LOCATION);
   // Make sure we have a metric value for each of the two localities.
   EXPECT_THAT(
       stats_plugin->GetHistogramValue(kEndpointWeights, kLabelValues,