Later CLs will clean up the ClientHello construction a bit (draft-12
avoids computing ClientHelloOuter twice). I suspect the transcript
handling on the client can also be simpler, but I'll see what's
convenient after I've changed how ClientHelloOuter is constructed.
Changes of note between draft-10 and draft-13:
- There is now an ECH confirmation signal in both HRR and SH. We don't
actually make much use of this in our client right now, but it
resolves a bunch of weird issues around HRR, including edge cases if
HRR applies to one ClientHello but not the other.
- The confirmation signal no longer depends on key_share and PSK, so we
don't have to work around a weird ordering issue.
- ech_is_inner is now folded into the main encrypted_client_hello code
point. This works better with some stuff around HRR.
- Padding is moved from the padding extension, computed with
ClientHelloInner, to something we fill in afterwards. This makes it
easier to pad up the whole thing to a multiple of 32. I've accordingly
updated to the latest recommended padding construction, and updated
the GREASE logic to match.
- ech_outer_extensions is much easier to process because the order is
required to be consistent. We were doing that anyway, and now a simple
linear scan works.
- ClientHelloOuterAAD now uses an all zero placeholder payload of the
same length. This lets us simplify the server code, but, for now, I've
kept the client code the same. I'll follow this up with a CL to avoid
computing ClientHelloOuter twice.
- ClientHelloOuterAAD is allowed to contain a placeholder PSK. I haven't
filled that in and will do it in a follow-up CL.
Bug: 275
Change-Id: I7464345125c53968b2fe692f9268e392120fc2eb
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48912
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Based on an initial implementation by Dan McArdle at
https://boringssl-review.googlesource.com/c/boringssl/+/46784
This CL contains most of a client implementation for
draft-ietf-tls-esni-10. The pieces missing so far, which will be done in
follow-up CLs are:
1. While the ClientHelloInner is padded, the server Certificate message
is not. I'll add that once we resolve the spec discussions on how to
do that. (We were originally going to use TLS record-level padding,
but that doesn't work well with QUIC.)
2. The client should check the public name is a valid DNS name before
copying it into ClientHelloOuter.server_name.
3. The ClientHelloOuter handshake flow is not yet implemented. This CL
can detect when the server selects ClientHelloOuter, but for now the
handshake immediately fails. A follow-up CL will remove that logic
and instead add the APIs and extra checks needed.
Otherwise, this should be complete, including padding and compression.
The main interesting point design-wise is that we run through
ClientHello construction multiple times. We need to construct
ClientHelloInner and ClientHelloOuter. Then each of those has slight
variants: EncodedClientHelloInner is the compressed form, and
ClientHelloOuterAAD just has the ECH extension erased to avoid a
circular dependency.
I've computed ClientHelloInner and EncodedClientHelloInner concurrently
because the compression scheme requires shifting the extensions around
to be contiguous. However, I've computed ClientHelloOuterAAD and
ClientHelloOuter by running through the logic twice. This probably can
be done better, but the next draft revises the construction anyway, so
I'm thinking I'll rework it then. (In the next draft, we use a
placeholder payload of the same length, so we can construct the
ClientHello once and fill in the payload.)
Additionally, now that we have a client available in ssl_test, this adds
a threading test to confirm that SSL_CTX_set1_ech_keys is properly
synchronized. (Confirmed that, if I drop the lock in
SSL_CTX_set1_ech_keys, TSan notices.)
Change-Id: Icaff68b595035bdcc73c468ff638e67c84239ef4
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48004
Reviewed-by: Adam Langley <agl@google.com>
This implements draft-ietf-tls-esni-10.
This will be used to test the client implementation. While I'm here,
I've switched the setup logic in the server tests to use the new
ServerECHConfig type. I'll probably need to patch in various features
later for testing, but this should be a usable starting point.
Based on an initial implementation by Dan McArdle in
https://boringssl-review.googlesource.com/c/boringssl/+/46786
Bug: 275
Change-Id: I69523cda70c3da2ae505bcab837fd358195fb9e9
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47967
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Noticed this while I was in the area. We currently use an extremely lax
parse that even tolerates syntax errors. Instead use a strict parse that
ensures our client only sends what we expect.
Change-Id: Ifb0e1e1698489ff217db0c7a0317caa885e20759
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47966
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Having the nil vs. non-nil []byte for the sake of a couple tests with
invalid payloads is tedious. Use separate fields instead.
Bug: 275
Change-Id: I557d914d60ce94d68796c05162ff3dd2ab7684db
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47965
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
An ECHConfig is like a certificate in that knowing the fields isn't
sufficient. The exact byte representation is significant. (The ECHConfig
is bound into the encryption.) But the ECHConfig type only has fields,
so runner can only represent ECHConfigs that are the output of our
serialization function.
This matters less as a client testing a server because the server can
only parse ECHConfigs with fields we support. But as a server testing a
client, we need to see how the client reacts to extra extensions, etc.
Just using []byte to represent ECHConfigs is inconvenient, so instead
pattern this after x509.Certificate: you can parse one from a byte
string (not currently included since we don't need it yet), or you can
construct a new one from a template with the fields you want.
Bug: 275
Change-Id: I6602d0780b1cef12b6c4b442999bdff7b3d7dd70
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47964
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
We misread (or maybe it changed?) the draft padding scheme. The current
text does not round the whole payload to a multiple of 32, just the
server name as a fallback. Switch the GREASE size selection to match.
Although, we may want to change the draft here. See also
https://github.com/tlswg/draft-ietf-tls-esni/issues/433
While I'm here, update some references from draft-09 to draft-10. Also
make the comment less verbose.
Bug: 275
Change-Id: I3c9f34159890bc3b7d71f6877f34b895bc7f9b17
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47644
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
We didn't end up deploying this. We also never implemented the final
RFC, so what we do have isn't useful for someone who wishes to deploy
it anyway.
Update-Note: Token binding APIs are removed.
Change-Id: Iecea7c3dcf9d3e2644a3b7afaf61511310b45d5f
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47584
Reviewed-by: Adam Langley <agl@google.com>
Bug: 275
Change-Id: I8096070386af7d2b5020875ea09bcc0c04ebc8cd
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47245
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: Steven Valdez <svaldez@google.com>
This CL adds an initial implementation of the ECH server, with pieces of
the client in BoGo as necessary for testing. In particular, the server
supports ClientHelloInner compression with ech_outer_extensions. When
ECH decryption fails, it can send retry_configs back to the client.
This server passes the "ech-accept" and "ech-reject" test cases in
tls-interop-runner[0] when tested against both the cloudflare-go and nss
clients. For reproducibility, I started with the main branch at commit
707604c262d8bcf3e944ed1d5a675077304732ce and updated the endpoint's
script to pass the server's ECHConfig and private key to the boringssl
tool.
Follow-up CLs will update HPKE to the latest draft and catch us up to
draft-10.
[0]: https://github.com/xvzcf/tls-interop-runner
Bug: 275
Change-Id: I49be35af46d1fd5dd9c62252f07d0bae179381ab
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/45285
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
The client handshake currently defers creating the finishedHash and
writing things into the transcript, which is a little annoying for ECH.
In preparation for simplifying that, one nuisance is that we retain both
hello and helloBytes, across a long span of code. helloBytes is *almost*
the same as hello.marshal() except:
- When we send a V2ClientHello, helloBytes records that we serialized
the ClientHello completely differently.
- For the JDK11 workaround tests, helloBytes records that we swapped out
the ClientHello entirely.
- By the time we finally write helloBytes into the transcript, hello may
have been updated to the second ClientHello.
This CL resolves the first two issues. It replaces the v2ClientHelloMsg
with an option when serializing the clientHelloMsg, and it has the
ClientHello replacement function return a clientHelloMsg instead of a
[]byte. (This is a little weird because we're conflating parsed and
constructed ClientHellos, but ah well.)
A follow-up CL will remove the differed transcript bits and we'll
actually be able to drop helloBytes.
Change-Id: Ib82ac216604e2c4bf421277e57aa5fd3b4cef161
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/46629
Reviewed-by: Adam Langley <agl@google.com>
Re-encoding a message does not necessarily give back the same value.
Bug: 275
Change-Id: I52cddd6152445b70579cbe03525898383bee211d
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/46644
Reviewed-by: David Benjamin <davidben@google.com>
Reviewed-by: Dan McArdle <dmcardle@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
We only need to implement enough of SSL 3.0 to test that the shim does
not.
Change-Id: I25cb48e407f1bc458bbdb3544b9df9fdfbc3d9c9
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/46625
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
In early TLS 1.3 drafts, HelloRetryRequest was a dedicated message type.
Our HelloRetryRequest handling in runner is still based on this. Along
the way, remove the SendServerHelloAsHelloRetryRequest test, since
that's just a generic unexpected message type now.
Change-Id: Idd9c54d0ab66d962657af9a53849c3928f78ce5c
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/46585
Reviewed-by: Adam Langley <agl@google.com>
A linter was complaining about some instance, so just fix the lot of it.
Change-Id: I7e23cbada6e42da887d740b84a05de9f104a86ab
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/45284
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
IETF QUIC draft 33 is replacing the TLS extension
codepoint for QUIC transport parameters from 0xffa5
to 57. To support multiple versions of Chrome, we
need to support both codepoints in BoringSSL. This
CL adds support for the new codepoint in a way that
can be enabled on individual connections.
Note that when BoringSSL is not in QUIC mode, it
will error if it sees the new codepoint as a server
but it will ignore the legacy codepoint as that could
be a different private usage of that codepoint.
Change-Id: I314f8f0b169cedd96eeccc42b44153e97044388c
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/44704
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
This CL implements the backend server behavior described in Section 7.2
of draft-ietf-tls-esni-09.
Bug: 275
Change-Id: I2e162673ce564db0cb75fc9b71ef11ed15037f4b
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/43924
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
(Original CL by svaldez, reworked by davidben.)
Change-Id: I8570808fa5e96a1c9e6e03c4877039a22e73254f
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/42404
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
The Go TLS implementation, at the time runner forked, had custom
testing-only equal methods on all the handshake messages. We've since
removed all of them except for ClientHello, where we repurposed the
function to check ClientHello consistency on HelloVerifyRequest and
HelloRetryRequest.
These are tedious to update. Upstream has since replaced them with
reflect.DeepEqual, but the comparison we want is even tighter. Even
unknown extensions aren't allowed to change. Replace the check with a
custom one that works on the byte serialization and remove
clientHelloMsg.equal.
Along the way, I've fixed the HRR PSK identity logic to match the spec a
bit more and check binders more consistently.
Change-Id: Ib39e8791201c42d37e304ae5110c7aeed62c8b3f
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/43364
Reviewed-by: Adam Langley <agl@google.com>
Reviewed-by: Steven Valdez <svaldez@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
This CL replaces clientHelloMsg's npnAfterAlpn and pskBinderFirst fields
with a new field: prefixExtensions. The extensions in prefixExtensions
are tried first when marshalling clientHelloMsg.
The ability to control extensions' marshalling order will make it
simpler to implement the "outer_extensions" behavior defined in
draft-ietf-tls-esni-07.
Bug: 275
Change-Id: Ib6dcc1e6fa0281f312cb65a9e204415c3f3ef2c6
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/43064
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
This version adds signature algorithms to the extension
Change-Id: I91dc78d33ee81cb7a6221c7bdeefc8ea460a2d6c
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/42424
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
David Benjamin
Steven Valdez
Daniel McArdle
David Schinazi
Watson Ladd
Adam Langley