Merge pull request #12359 from justinburke/tsi_factory_locking

Add reference counting to tsi_ssl_handshaker_factories

src/core/lib/http/httpcli_security_connector.c

@@ -43,7 +43,8 @@ static void httpcli_ssl_destroy(grpc_exec_ctx *exec_ctx,
   grpc_httpcli_ssl_channel_security_connector *c =
       (grpc_httpcli_ssl_channel_security_connector *)sc;
   if (c->handshaker_factory != NULL) {
-    tsi_ssl_client_handshaker_factory_destroy(c->handshaker_factory);
+    tsi_ssl_client_handshaker_factory_unref(c->handshaker_factory);
+    c->handshaker_factory = NULL;
   }
   if (c->secure_peer_name != NULL) gpr_free(c->secure_peer_name);
   gpr_free(sc);

src/core/lib/security/transport/security_connector.c

@@ -455,14 +455,14 @@ grpc_server_security_connector *grpc_fake_server_security_connector_create(
 
 typedef struct {
   grpc_channel_security_connector base;
-  tsi_ssl_client_handshaker_factory *handshaker_factory;
+  tsi_ssl_client_handshaker_factory *client_handshaker_factory;
   char *target_name;
   char *overridden_target_name;
 } grpc_ssl_channel_security_connector;
 
 typedef struct {
   grpc_server_security_connector base;
-  tsi_ssl_server_handshaker_factory *handshaker_factory;
+  tsi_ssl_server_handshaker_factory *server_handshaker_factory;
 } grpc_ssl_server_security_connector;
 
 static void ssl_channel_destroy(grpc_exec_ctx *exec_ctx,
@@ -470,9 +470,8 @@ static void ssl_channel_destroy(grpc_exec_ctx *exec_ctx,
   grpc_ssl_channel_security_connector *c =
       (grpc_ssl_channel_security_connector *)sc;
   grpc_call_credentials_unref(exec_ctx, c->base.request_metadata_creds);
-  if (c->handshaker_factory != NULL) {
+  tsi_ssl_client_handshaker_factory_unref(c->client_handshaker_factory);
-    tsi_ssl_client_handshaker_factory_destroy(c->handshaker_factory);
+  c->client_handshaker_factory = NULL;
-  }
   if (c->target_name != NULL) gpr_free(c->target_name);
   if (c->overridden_target_name != NULL) gpr_free(c->overridden_target_name);
   gpr_free(sc);
@@ -482,9 +481,8 @@ static void ssl_server_destroy(grpc_exec_ctx *exec_ctx,
                                grpc_security_connector *sc) {
   grpc_ssl_server_security_connector *c =
       (grpc_ssl_server_security_connector *)sc;
-  if (c->handshaker_factory != NULL) {
+  tsi_ssl_server_handshaker_factory_unref(c->server_handshaker_factory);
-    tsi_ssl_server_handshaker_factory_destroy(c->handshaker_factory);
+  c->server_handshaker_factory = NULL;
-  }
   gpr_free(sc);
 }
 
@@ -496,7 +494,7 @@ static void ssl_channel_add_handshakers(grpc_exec_ctx *exec_ctx,
   // Instantiate TSI handshaker.
   tsi_handshaker *tsi_hs = NULL;
   tsi_result result = tsi_ssl_client_handshaker_factory_create_handshaker(
-      c->handshaker_factory,
+      c->client_handshaker_factory,
       c->overridden_target_name != NULL ? c->overridden_target_name
                                         : c->target_name,
       &tsi_hs);
@@ -521,7 +519,7 @@ static void ssl_server_add_handshakers(grpc_exec_ctx *exec_ctx,
   // Instantiate TSI handshaker.
   tsi_handshaker *tsi_hs = NULL;
   tsi_result result = tsi_ssl_server_handshaker_factory_create_handshaker(
-      c->handshaker_factory, &tsi_hs);
+      c->server_handshaker_factory, &tsi_hs);
   if (result != TSI_OK) {
     gpr_log(GPR_ERROR, "Handshaker creation failed with error %s.",
             tsi_result_to_string(result));
@@ -852,7 +850,7 @@ grpc_security_status grpc_ssl_channel_security_connector_create(
   result = tsi_create_ssl_client_handshaker_factory(
       has_key_cert_pair ? &config->pem_key_cert_pair : NULL, pem_root_certs,
       ssl_cipher_suites(), alpn_protocol_strings, (uint16_t)num_alpn_protocols,
-      &c->handshaker_factory);
+      &c->client_handshaker_factory);
   if (result != TSI_OK) {
     gpr_log(GPR_ERROR, "Handshaker factory creation failed with %s.",
             tsi_result_to_string(result));
@@ -897,7 +895,7 @@ grpc_security_status grpc_ssl_server_security_connector_create(
       config->pem_root_certs, get_tsi_client_certificate_request_type(
                                   config->client_certificate_request),
       ssl_cipher_suites(), alpn_protocol_strings, (uint16_t)num_alpn_protocols,
-      &c->handshaker_factory);
+      &c->server_handshaker_factory);
   if (result != TSI_OK) {
     gpr_log(GPR_ERROR, "Handshaker factory creation failed with %s.",
             tsi_result_to_string(result));

src/core/tsi/ssl_transport_security.c

@@ -67,7 +67,13 @@
 
 /* --- Structure definitions. ---*/
 
+struct tsi_ssl_handshaker_factory {
+  const tsi_ssl_handshaker_factory_vtable *vtable;
+  gpr_refcount refcount;
+};
+
 struct tsi_ssl_client_handshaker_factory {
+  tsi_ssl_handshaker_factory base;
   SSL_CTX *ssl_context;
   unsigned char *alpn_protocol_list;
   size_t alpn_protocol_list_length;
@@ -77,6 +83,7 @@ struct tsi_ssl_server_handshaker_factory {
   /* Several contexts to support SNI.
      The tsi_peer array contains the subject names of the server certificates
      associated with the contexts at the same index.  */
+  tsi_ssl_handshaker_factory base;
   SSL_CTX **ssl_contexts;
   tsi_peer *ssl_context_x509_subject_names;
   size_t ssl_context_count;
@@ -90,6 +97,7 @@ typedef struct {
   BIO *into_ssl;
   BIO *from_ssl;
   tsi_result result;
+  tsi_ssl_handshaker_factory *factory_ref;
 } tsi_ssl_handshaker;
 
 typedef struct {
@@ -846,6 +854,47 @@ static const tsi_frame_protector_vtable frame_protector_vtable = {
     ssl_protector_destroy,
 };
 
+/* --- tsi_server_handshaker_factory methods implementation. --- */
+
+static void tsi_ssl_handshaker_factory_destroy(
+    tsi_ssl_handshaker_factory *self) {
+  if (self == NULL) return;
+
+  if (self->vtable != NULL && self->vtable->destroy != NULL) {
+    self->vtable->destroy(self);
+  }
+  /* Note, we don't free(self) here because this object is always directly
+   * embedded in another object. If tsi_ssl_handshaker_factory_init allocates
+   * any memory, it should be free'd here. */
+}
+
+static tsi_ssl_handshaker_factory *tsi_ssl_handshaker_factory_ref(
+    tsi_ssl_handshaker_factory *self) {
+  if (self == NULL) return NULL;
+  gpr_refn(&self->refcount, 1);
+  return self;
+}
+
+static void tsi_ssl_handshaker_factory_unref(tsi_ssl_handshaker_factory *self) {
+  if (self == NULL) return;
+
+  if (gpr_unref(&self->refcount)) {
+    tsi_ssl_handshaker_factory_destroy(self);
+  }
+}
+
+static tsi_ssl_handshaker_factory_vtable handshaker_factory_vtable = {NULL};
+
+/* Initializes a tsi_ssl_handshaker_factory object. Caller is responsible for
+ * allocating memory for the factory. */
+static void tsi_ssl_handshaker_factory_init(
+    tsi_ssl_handshaker_factory *factory) {
+  GPR_ASSERT(factory != NULL);
+
+  factory->vtable = &handshaker_factory_vtable;
+  gpr_ref_init(&factory->refcount, 1);
+}
+
 /* --- tsi_handshaker methods implementation. ---*/
 
 static tsi_result ssl_handshaker_get_bytes_to_send_to_peer(tsi_handshaker *self,
@@ -1013,6 +1062,7 @@ static tsi_result ssl_handshaker_create_frame_protector(
 static void ssl_handshaker_destroy(tsi_handshaker *self) {
   tsi_ssl_handshaker *impl = (tsi_ssl_handshaker *)self;
   SSL_free(impl->ssl); /* The BIO objects are owned by ssl */
+  tsi_ssl_handshaker_factory_unref(impl->factory_ref);
   gpr_free(impl);
 }
 
@@ -1030,6 +1080,7 @@ static const tsi_handshaker_vtable handshaker_vtable = {
 
 static tsi_result create_tsi_ssl_handshaker(SSL_CTX *ctx, int is_client,
                                             const char *server_name_indication,
+                                            tsi_ssl_handshaker_factory *factory,
                                             tsi_handshaker **handshaker) {
   SSL *ssl = SSL_new(ctx);
   BIO *into_ssl = NULL;
@@ -1085,6 +1136,8 @@ static tsi_result create_tsi_ssl_handshaker(SSL_CTX *ctx, int is_client,
   impl->from_ssl = from_ssl;
   impl->result = TSI_HANDSHAKE_IN_PROGRESS;
   impl->base.vtable = &handshaker_vtable;
+  impl->factory_ref = tsi_ssl_handshaker_factory_ref(factory);
+
   *handshaker = &impl->base;
   return TSI_OK;
 }
@@ -1121,11 +1174,20 @@ tsi_result tsi_ssl_client_handshaker_factory_create_handshaker(
     tsi_ssl_client_handshaker_factory *self, const char *server_name_indication,
     tsi_handshaker **handshaker) {
   return create_tsi_ssl_handshaker(self->ssl_context, 1, server_name_indication,
-                                   handshaker);
+                                   &self->base, handshaker);
 }
 
-void tsi_ssl_client_handshaker_factory_destroy(
+void tsi_ssl_client_handshaker_factory_unref(
     tsi_ssl_client_handshaker_factory *self) {
+  if (self == NULL) return;
+  tsi_ssl_handshaker_factory_unref(&self->base);
+}
+
+static void tsi_ssl_client_handshaker_factory_destroy(
+    tsi_ssl_handshaker_factory *factory) {
+  if (factory == NULL) return;
+  tsi_ssl_client_handshaker_factory *self =
+      (tsi_ssl_client_handshaker_factory *)factory;
   if (self->ssl_context != NULL) SSL_CTX_free(self->ssl_context);
   if (self->alpn_protocol_list != NULL) gpr_free(self->alpn_protocol_list);
   gpr_free(self);
@@ -1150,11 +1212,21 @@ tsi_result tsi_ssl_server_handshaker_factory_create_handshaker(
   if (self->ssl_context_count == 0) return TSI_INVALID_ARGUMENT;
   /* Create the handshaker with the first context. We will switch if needed
      because of SNI in ssl_server_handshaker_factory_servername_callback.  */
-  return create_tsi_ssl_handshaker(self->ssl_contexts[0], 0, NULL, handshaker);
+  return create_tsi_ssl_handshaker(self->ssl_contexts[0], 0, NULL, &self->base,
+                                   handshaker);
 }
 
-void tsi_ssl_server_handshaker_factory_destroy(
+void tsi_ssl_server_handshaker_factory_unref(
     tsi_ssl_server_handshaker_factory *self) {
+  if (self == NULL) return;
+  tsi_ssl_handshaker_factory_unref(&self->base);
+}
+
+static void tsi_ssl_server_handshaker_factory_destroy(
+    tsi_ssl_handshaker_factory *factory) {
+  if (factory == NULL) return;
+  tsi_ssl_server_handshaker_factory *self =
+      (tsi_ssl_server_handshaker_factory *)factory;
   size_t i;
   for (i = 0; i < self->ssl_context_count; i++) {
     if (self->ssl_contexts[i] != NULL) {
@@ -1263,6 +1335,9 @@ static int server_handshaker_factory_npn_advertised_callback(
 
 /* --- tsi_ssl_handshaker_factory constructors. --- */
 
+static tsi_ssl_handshaker_factory_vtable client_handshaker_factory_vtable = {
+    tsi_ssl_client_handshaker_factory_destroy};
+
 tsi_result tsi_create_ssl_client_handshaker_factory(
     const tsi_ssl_pem_key_cert_pair *pem_key_cert_pair,
     const char *pem_root_certs, const char *cipher_suites,
@@ -1285,6 +1360,9 @@ tsi_result tsi_create_ssl_client_handshaker_factory(
   }
 
   impl = gpr_zalloc(sizeof(*impl));
+  tsi_ssl_handshaker_factory_init(&impl->base);
+  impl->base.vtable = &client_handshaker_factory_vtable;
+
   impl->ssl_context = ssl_context;
 
   do {
@@ -1322,7 +1400,7 @@ tsi_result tsi_create_ssl_client_handshaker_factory(
     }
   } while (0);
   if (result != TSI_OK) {
-    tsi_ssl_client_handshaker_factory_destroy(impl);
+    tsi_ssl_handshaker_factory_unref(&impl->base);
     return result;
   }
   SSL_CTX_set_verify(ssl_context, SSL_VERIFY_PEER, NULL);
@@ -1332,6 +1410,9 @@ tsi_result tsi_create_ssl_client_handshaker_factory(
   return TSI_OK;
 }
 
+static tsi_ssl_handshaker_factory_vtable server_handshaker_factory_vtable = {
+    tsi_ssl_server_handshaker_factory_destroy};
+
 tsi_result tsi_create_ssl_server_handshaker_factory(
     const tsi_ssl_pem_key_cert_pair *pem_key_cert_pairs,
     size_t num_key_cert_pairs, const char *pem_client_root_certs,
@@ -1364,12 +1445,15 @@ tsi_result tsi_create_ssl_server_handshaker_factory_ex(
   }
 
   impl = gpr_zalloc(sizeof(*impl));
+  tsi_ssl_handshaker_factory_init(&impl->base);
+  impl->base.vtable = &server_handshaker_factory_vtable;
+
   impl->ssl_contexts = gpr_zalloc(num_key_cert_pairs * sizeof(SSL_CTX *));
   impl->ssl_context_x509_subject_names =
       gpr_zalloc(num_key_cert_pairs * sizeof(tsi_peer));
   if (impl->ssl_contexts == NULL ||
       impl->ssl_context_x509_subject_names == NULL) {
-    tsi_ssl_server_handshaker_factory_destroy(impl);
+    tsi_ssl_handshaker_factory_unref(&impl->base);
     return TSI_OUT_OF_RESOURCES;
   }
   impl->ssl_context_count = num_key_cert_pairs;
@@ -1379,7 +1463,7 @@ tsi_result tsi_create_ssl_server_handshaker_factory_ex(
                                            &impl->alpn_protocol_list,
                                            &impl->alpn_protocol_list_length);
     if (result != TSI_OK) {
-      tsi_ssl_server_handshaker_factory_destroy(impl);
+      tsi_ssl_handshaker_factory_unref(&impl->base);
       return result;
     }
   }
@@ -1451,10 +1535,11 @@ tsi_result tsi_create_ssl_server_handshaker_factory_ex(
     } while (0);
 
     if (result != TSI_OK) {
-      tsi_ssl_server_handshaker_factory_destroy(impl);
+      tsi_ssl_handshaker_factory_unref(&impl->base);
       return result;
     }
   }
+
   *factory = impl;
   return TSI_OK;
 }
@@ -1501,3 +1586,15 @@ int tsi_ssl_peer_matches_name(const tsi_peer *peer, const char *name) {
 
   return 0; /* Not found. */
 }
+
+/* --- Testing support. --- */
+const tsi_ssl_handshaker_factory_vtable *tsi_ssl_handshaker_factory_swap_vtable(
+    tsi_ssl_handshaker_factory *factory,
+    tsi_ssl_handshaker_factory_vtable *new_vtable) {
+  GPR_ASSERT(factory != NULL);
+  GPR_ASSERT(factory->vtable != NULL);
+
+  const tsi_ssl_handshaker_factory_vtable *orig_vtable = factory->vtable;
+  factory->vtable = new_vtable;
+  return orig_vtable;
+}

src/core/tsi/ssl_transport_security.h

@@ -96,10 +96,10 @@ tsi_result tsi_ssl_client_handshaker_factory_create_handshaker(
     tsi_ssl_client_handshaker_factory *self, const char *server_name_indication,
     tsi_handshaker **handshaker);
 
-/* Destroys the handshaker factory. WARNING: it is unsafe to destroy a factory
+/* Decrements reference count of the handshaker factory. Handshaker factory will
-   while handshakers created with this factory are still in use.  */
+ * be destroyed once no references exist. */
-void tsi_ssl_client_handshaker_factory_destroy(
+void tsi_ssl_client_handshaker_factory_unref(
-    tsi_ssl_client_handshaker_factory *self);
+    tsi_ssl_client_handshaker_factory *factory);
 
 /* --- tsi_ssl_server_handshaker_factory object ---
 
@@ -158,9 +158,9 @@ tsi_result tsi_create_ssl_server_handshaker_factory_ex(
 tsi_result tsi_ssl_server_handshaker_factory_create_handshaker(
     tsi_ssl_server_handshaker_factory *self, tsi_handshaker **handshaker);
 
-/* Destroys the handshaker factory. WARNING: it is unsafe to destroy a factory
+/* Decrements reference count of the handshaker factory. Handshaker factory will
-   while handshakers created with this factory are still in use.  */
+ * be destroyed once no references exist. */
-void tsi_ssl_server_handshaker_factory_destroy(
+void tsi_ssl_server_handshaker_factory_unref(
     tsi_ssl_server_handshaker_factory *self);
 
 /* Util that checks that an ssl peer matches a specific name.
@@ -170,6 +170,29 @@ void tsi_ssl_server_handshaker_factory_destroy(
    - handle public suffix wildchar more strictly (e.g. *.co.uk) */
 int tsi_ssl_peer_matches_name(const tsi_peer *peer, const char *name);
 
+/* --- Testing support. ---
+
+   These functions and typedefs are not intended to be used outside of testing.
+   */
+
+/* Base type of client and server handshaker factories. */
+typedef struct tsi_ssl_handshaker_factory tsi_ssl_handshaker_factory;
+
+/* Function pointer to handshaker_factory destructor. */
+typedef void (*tsi_ssl_handshaker_factory_destructor)(
+    tsi_ssl_handshaker_factory *factory);
+
+/* Virtual table for tsi_ssl_handshaker_factory. */
+typedef struct {
+  tsi_ssl_handshaker_factory_destructor destroy;
+} tsi_ssl_handshaker_factory_vtable;
+
+/* Set destructor of handshaker_factory to new_destructor, returns previous
+   destructor. */
+const tsi_ssl_handshaker_factory_vtable *tsi_ssl_handshaker_factory_swap_vtable(
+    tsi_ssl_handshaker_factory *factory,
+    tsi_ssl_handshaker_factory_vtable *new_vtable);
+
 #ifdef __cplusplus
 }
 #endif

test/core/tsi/ssl_transport_security_test.c

@@ -23,7 +23,9 @@
 #include "src/core/lib/iomgr/load_file.h"
 #include "src/core/lib/security/transport/security_connector.h"
 #include "src/core/tsi/ssl_transport_security.h"
+#include "src/core/tsi/transport_security.h"
 #include "src/core/tsi/transport_security_adapter.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"
 
@@ -312,10 +314,10 @@ static void ssl_test_destruct(tsi_test_fixture *fixture) {
       key_cert_lib->bad_client_pem_key_cert_pair);
   gpr_free(key_cert_lib->root_cert);
   gpr_free(key_cert_lib);
-  /* Destroy others. */
+  /* Unreference others. */
-  tsi_ssl_server_handshaker_factory_destroy(
+  tsi_ssl_server_handshaker_factory_unref(
       ssl_fixture->server_handshaker_factory);
-  tsi_ssl_client_handshaker_factory_destroy(
+  tsi_ssl_client_handshaker_factory_unref(
       ssl_fixture->client_handshaker_factory);
 }
 
@@ -536,6 +538,118 @@ void ssl_tsi_test_do_round_trip_odd_buffer_size() {
   }
 }
 
+static const tsi_ssl_handshaker_factory_vtable *original_vtable;
+static bool handshaker_factory_destructor_called;
+
+static void ssl_tsi_test_handshaker_factory_destructor(
+    tsi_ssl_handshaker_factory *factory) {
+  GPR_ASSERT(factory != NULL);
+  handshaker_factory_destructor_called = true;
+  if (original_vtable != NULL && original_vtable->destroy != NULL) {
+    original_vtable->destroy(factory);
+  }
+}
+
+static tsi_ssl_handshaker_factory_vtable test_handshaker_factory_vtable = {
+    ssl_tsi_test_handshaker_factory_destructor};
+
+void test_tsi_ssl_client_handshaker_factory_refcounting() {
+  int i;
+  const char *cert_chain =
+      load_file(SSL_TSI_TEST_CREDENTIALS_DIR, "client.pem");
+
+  tsi_ssl_client_handshaker_factory *client_handshaker_factory;
+  GPR_ASSERT(tsi_create_ssl_client_handshaker_factory(
+                 NULL, cert_chain, NULL, NULL, 0, &client_handshaker_factory) ==
+             TSI_OK);
+
+  handshaker_factory_destructor_called = false;
+  original_vtable = tsi_ssl_handshaker_factory_swap_vtable(
+      (tsi_ssl_handshaker_factory *)client_handshaker_factory,
+      &test_handshaker_factory_vtable);
+
+  tsi_handshaker *handshaker[3];
+
+  for (i = 0; i < 3; ++i) {
+    GPR_ASSERT(tsi_ssl_client_handshaker_factory_create_handshaker(
+                   client_handshaker_factory, "google.com", &handshaker[i]) ==
+               TSI_OK);
+  }
+
+  tsi_handshaker_destroy(handshaker[1]);
+  GPR_ASSERT(!handshaker_factory_destructor_called);
+
+  tsi_handshaker_destroy(handshaker[0]);
+  GPR_ASSERT(!handshaker_factory_destructor_called);
+
+  tsi_ssl_client_handshaker_factory_unref(client_handshaker_factory);
+  GPR_ASSERT(!handshaker_factory_destructor_called);
+
+  tsi_handshaker_destroy(handshaker[2]);
+  GPR_ASSERT(handshaker_factory_destructor_called);
+
+  gpr_free((void *)cert_chain);
+}
+
+void test_tsi_ssl_server_handshaker_factory_refcounting() {
+  int i;
+  tsi_ssl_server_handshaker_factory *server_handshaker_factory;
+  tsi_handshaker *handshaker[3];
+  const char *cert_chain =
+      load_file(SSL_TSI_TEST_CREDENTIALS_DIR, "server0.pem");
+  tsi_ssl_pem_key_cert_pair cert_pair;
+
+  cert_pair.cert_chain = cert_chain;
+  cert_pair.private_key =
+      load_file(SSL_TSI_TEST_CREDENTIALS_DIR, "server0.key");
+
+  GPR_ASSERT(tsi_create_ssl_server_handshaker_factory(
+                 &cert_pair, 1, cert_chain, 0, NULL, NULL, 0,
+                 &server_handshaker_factory) == TSI_OK);
+
+  handshaker_factory_destructor_called = false;
+  original_vtable = tsi_ssl_handshaker_factory_swap_vtable(
+      (tsi_ssl_handshaker_factory *)server_handshaker_factory,
+      &test_handshaker_factory_vtable);
+
+  for (i = 0; i < 3; ++i) {
+    GPR_ASSERT(tsi_ssl_server_handshaker_factory_create_handshaker(
+                   server_handshaker_factory, &handshaker[i]) == TSI_OK);
+  }
+
+  tsi_handshaker_destroy(handshaker[1]);
+  GPR_ASSERT(!handshaker_factory_destructor_called);
+
+  tsi_handshaker_destroy(handshaker[0]);
+  GPR_ASSERT(!handshaker_factory_destructor_called);
+
+  tsi_ssl_server_handshaker_factory_unref(server_handshaker_factory);
+  GPR_ASSERT(!handshaker_factory_destructor_called);
+
+  tsi_handshaker_destroy(handshaker[2]);
+  GPR_ASSERT(handshaker_factory_destructor_called);
+
+  ssl_test_pem_key_cert_pair_destroy(cert_pair);
+}
+
+/* Attempting to create a handshaker factory with invalid parameters should fail
+ * but not crash. */
+void test_tsi_ssl_client_handshaker_factory_bad_params() {
+  const char *cert_chain = "This is not a valid PEM file.";
+
+  tsi_ssl_client_handshaker_factory *client_handshaker_factory;
+  GPR_ASSERT(tsi_create_ssl_client_handshaker_factory(
+                 NULL, cert_chain, NULL, NULL, 0, &client_handshaker_factory) ==
+             TSI_INVALID_ARGUMENT);
+  tsi_ssl_client_handshaker_factory_unref(client_handshaker_factory);
+}
+
+void ssl_tsi_test_handshaker_factory_internals() {
+  test_tsi_ssl_client_handshaker_factory_refcounting();
+  test_tsi_ssl_server_handshaker_factory_refcounting();
+  test_tsi_ssl_client_handshaker_factory_bad_params();
+}
+
 int main(int argc, char **argv) {
   grpc_test_init(argc, argv);
   grpc_init();
@@ -553,6 +667,7 @@ int main(int argc, char **argv) {
   ssl_tsi_test_do_handshake_alpn_client_server_ok();
   ssl_tsi_test_do_round_trip_for_all_configs();
   ssl_tsi_test_do_round_trip_odd_buffer_size();
+  ssl_tsi_test_handshaker_factory_internals();
   grpc_shutdown();
   return 0;
 }