Use existing read buffer in security handshaker if present

10 files changed, 525 insertions, 220 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3ac6c9b63d..b3cbbbaea5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -466,6 +466,9 @@ endif()
 if(_gRPC_PLATFORM_LINUX)
 add_dependencies(buildtests_c handshake_server)
 endif()
+if(_gRPC_PLATFORM_LINUX)
+add_dependencies(buildtests_c handshake_server_with_readahead_handshaker)
+endif()
 add_dependencies(buildtests_c hpack_parser_test)
 add_dependencies(buildtests_c hpack_table_test)
 add_dependencies(buildtests_c http_parser_test)
@@ -7395,6 +7398,7 @@ if(_gRPC_PLATFORM_LINUX)
 
 add_executable(handshake_server
   test/core/handshake/server_ssl.c
+  test/core/handshake/server_ssl_common.c
 )
 
 
@@ -7424,6 +7428,40 @@ target_link_libraries(handshake_server
 endif()
 endif (gRPC_BUILD_TESTS)
 if (gRPC_BUILD_TESTS)
+if(_gRPC_PLATFORM_LINUX)
+
+add_executable(handshake_server_with_readahead_handshaker
+  test/core/handshake/readahead_handshaker_server_ssl.c
+  test/core/handshake/server_ssl_common.c
+)
+
+
+target_include_directories(handshake_server_with_readahead_handshaker
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/include
+  PRIVATE ${BORINGSSL_ROOT_DIR}/include
+  PRIVATE ${PROTOBUF_ROOT_DIR}/src
+  PRIVATE ${BENCHMARK_ROOT_DIR}/include
+  PRIVATE ${ZLIB_ROOT_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/zlib
+  PRIVATE ${CARES_INCLUDE_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/cares/cares
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/gflags/include
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/third_party/abseil-cpp
+)
+
+target_link_libraries(handshake_server_with_readahead_handshaker
+  ${_gRPC_SSL_LIBRARIES}
+  ${_gRPC_ALLTARGETS_LIBRARIES}
+  grpc_test_util
+  grpc
+  gpr_test_util
+  gpr
+)
+
+endif()
+endif (gRPC_BUILD_TESTS)
+if (gRPC_BUILD_TESTS)
 
 add_executable(hpack_parser_test
   test/core/transport/chttp2/hpack_parser_test.c
diff --git a/Makefile b/Makefile
index 325c9123d9..7c0ee0d17e 100644
--- a/Makefile
+++ b/Makefile
@@ -1023,6 +1023,7 @@ grpc_ssl_credentials_test: $(BINDIR)/$(CONFIG)/grpc_ssl_credentials_test
 grpc_verify_jwt: $(BINDIR)/$(CONFIG)/grpc_verify_jwt
 handshake_client: $(BINDIR)/$(CONFIG)/handshake_client
 handshake_server: $(BINDIR)/$(CONFIG)/handshake_server
+handshake_server_with_readahead_handshaker: $(BINDIR)/$(CONFIG)/handshake_server_with_readahead_handshaker
 hpack_parser_fuzzer_test: $(BINDIR)/$(CONFIG)/hpack_parser_fuzzer_test
 hpack_parser_test: $(BINDIR)/$(CONFIG)/hpack_parser_test
 hpack_table_test: $(BINDIR)/$(CONFIG)/hpack_table_test
@@ -1417,6 +1418,7 @@ buildtests_c: privatelibs_c \
   $(BINDIR)/$(CONFIG)/grpc_ssl_credentials_test \
   $(BINDIR)/$(CONFIG)/handshake_client \
   $(BINDIR)/$(CONFIG)/handshake_server \
+  $(BINDIR)/$(CONFIG)/handshake_server_with_readahead_handshaker \
   $(BINDIR)/$(CONFIG)/hpack_parser_test \
   $(BINDIR)/$(CONFIG)/hpack_table_test \
   $(BINDIR)/$(CONFIG)/http_parser_test \
@@ -1894,6 +1896,8 @@ test_c: buildtests_c
 	$(Q) $(BINDIR)/$(CONFIG)/handshake_client || ( echo test handshake_client failed ; exit 1 )
 	$(E) "[RUN]     Testing handshake_server"
 	$(Q) $(BINDIR)/$(CONFIG)/handshake_server || ( echo test handshake_server failed ; exit 1 )
+	$(E) "[RUN]     Testing handshake_server_with_readahead_handshaker"
+	$(Q) $(BINDIR)/$(CONFIG)/handshake_server_with_readahead_handshaker || ( echo test handshake_server_with_readahead_handshaker failed ; exit 1 )
 	$(E) "[RUN]     Testing hpack_parser_test"
 	$(Q) $(BINDIR)/$(CONFIG)/hpack_parser_test || ( echo test hpack_parser_test failed ; exit 1 )
 	$(E) "[RUN]     Testing hpack_table_test"
@@ -11221,6 +11225,7 @@ endif
 
 HANDSHAKE_SERVER_SRC = \
     test/core/handshake/server_ssl.c \
+    test/core/handshake/server_ssl_common.c \
 
 HANDSHAKE_SERVER_OBJS = $(addprefix $(OBJDIR)/$(CONFIG)/, $(addsuffix .o, $(basename $(HANDSHAKE_SERVER_SRC))))
 ifeq ($(NO_SECURE),true)
@@ -11242,6 +11247,8 @@ endif
 
 $(OBJDIR)/$(CONFIG)/test/core/handshake/server_ssl.o:  $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
 
+$(OBJDIR)/$(CONFIG)/test/core/handshake/server_ssl_common.o:  $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
+
 deps_handshake_server: $(HANDSHAKE_SERVER_OBJS:.o=.dep)
 
 ifneq ($(NO_SECURE),true)
@@ -11251,6 +11258,41 @@ endif
 endif
 
 
+HANDSHAKE_SERVER_WITH_READAHEAD_HANDSHAKER_SRC = \
+    test/core/handshake/readahead_handshaker_server_ssl.c \
+    test/core/handshake/server_ssl_common.c \
+
+HANDSHAKE_SERVER_WITH_READAHEAD_HANDSHAKER_OBJS = $(addprefix $(OBJDIR)/$(CONFIG)/, $(addsuffix .o, $(basename $(HANDSHAKE_SERVER_WITH_READAHEAD_HANDSHAKER_SRC))))
+ifeq ($(NO_SECURE),true)
+
+# You can't build secure targets if you don't have OpenSSL.
+
+$(BINDIR)/$(CONFIG)/handshake_server_with_readahead_handshaker: openssl_dep_error
+
+else
+
+
+
+$(BINDIR)/$(CONFIG)/handshake_server_with_readahead_handshaker: $(HANDSHAKE_SERVER_WITH_READAHEAD_HANDSHAKER_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
+	$(E) "[LD]      Linking $@"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(LD) $(LDFLAGS) $(HANDSHAKE_SERVER_WITH_READAHEAD_HANDSHAKER_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LDLIBS) $(LDLIBS_SECURE) -o $(BINDIR)/$(CONFIG)/handshake_server_with_readahead_handshaker
+
+endif
+
+$(OBJDIR)/$(CONFIG)/test/core/handshake/readahead_handshaker_server_ssl.o:  $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
+
+$(OBJDIR)/$(CONFIG)/test/core/handshake/server_ssl_common.o:  $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
+
+deps_handshake_server_with_readahead_handshaker: $(HANDSHAKE_SERVER_WITH_READAHEAD_HANDSHAKER_OBJS:.o=.dep)
+
+ifneq ($(NO_SECURE),true)
+ifneq ($(NO_DEPS),true)
+-include $(HANDSHAKE_SERVER_WITH_READAHEAD_HANDSHAKER_OBJS:.o=.dep)
+endif
+endif
+
+
 HPACK_PARSER_FUZZER_TEST_SRC = \
     test/core/transport/chttp2/hpack_parser_fuzzer_test.c \
 
diff --git a/build.yaml b/build.yaml
index 592cbb9f8c..adefb5d6d7 100644
--- a/build.yaml
+++ b/build.yaml
@@ -2579,6 +2579,23 @@ targets:
   language: c
   src:
   - test/core/handshake/server_ssl.c
+  - test/core/handshake/server_ssl_common.c
+  deps:
+  - grpc_test_util
+  - grpc
+  - gpr_test_util
+  - gpr
+  exclude_iomgrs:
+  - uv
+  platforms:
+  - linux
+  secure: true
+- name: handshake_server_with_readahead_handshaker
+  build: test
+  language: c
+  src:
+  - test/core/handshake/readahead_handshaker_server_ssl.c
+  - test/core/handshake/server_ssl_common.c
   deps:
   - grpc_test_util
   - grpc
diff --git a/src/core/lib/security/transport/security_handshaker.cc b/src/core/lib/security/transport/security_handshaker.cc
index 3d19605617..b42f2699ae 100644
--- a/src/core/lib/security/transport/security_handshaker.cc
+++ b/src/core/lib/security/transport/security_handshaker.cc
@@ -65,6 +65,25 @@ typedef struct {
   tsi_handshaker_result *handshaker_result;
 } security_handshaker;
 
+static size_t move_read_buffer_into_handshake_buffer(grpc_exec_ctx *exec_ctx,
+                                                     security_handshaker *h) {
+  size_t bytes_in_read_buffer = h->args->read_buffer->length;
+  if (h->handshake_buffer_size < bytes_in_read_buffer) {
+    h->handshake_buffer =
+        (uint8_t *)gpr_realloc(h->handshake_buffer, bytes_in_read_buffer);
+    h->handshake_buffer_size = bytes_in_read_buffer;
+  }
+  size_t offset = 0;
+  while (h->args->read_buffer->count > 0) {
+    grpc_slice next_slice = grpc_slice_buffer_take_first(h->args->read_buffer);
+    memcpy(h->handshake_buffer + offset, GRPC_SLICE_START_PTR(next_slice),
+           GRPC_SLICE_LENGTH(next_slice));
+    offset += GRPC_SLICE_LENGTH(next_slice);
+    grpc_slice_unref_internal(exec_ctx, next_slice);
+  }
+  return bytes_in_read_buffer;
+}
+
 static void security_handshaker_unref(grpc_exec_ctx *exec_ctx,
                                       security_handshaker *h) {
   if (gpr_unref(&h->refs)) {
@@ -177,8 +196,6 @@ static void on_peer_checked_inner(grpc_exec_ctx *exec_ctx,
   }
   tsi_handshaker_result_destroy(h->handshaker_result);
   h->handshaker_result = NULL;
-  // Clear out the read buffer before it gets passed to the transport.
-  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, h->args->read_buffer);
   // Add auth context to channel args.
   grpc_arg auth_context_arg = grpc_auth_context_to_arg(h->auth_context);
   grpc_channel_args *tmp_args = h->args->args;
@@ -311,23 +328,8 @@ static void on_handshake_data_received_from_peer(grpc_exec_ctx *exec_ctx,
     return;
   }
   // Copy all slices received.
-  size_t i;
-  size_t bytes_received_size = 0;
-  for (i = 0; i < h->args->read_buffer->count; i++) {
-    bytes_received_size += GRPC_SLICE_LENGTH(h->args->read_buffer->slices[i]);
-  }
-  if (bytes_received_size > h->handshake_buffer_size) {
-    h->handshake_buffer =
-        (uint8_t *)gpr_realloc(h->handshake_buffer, bytes_received_size);
-    h->handshake_buffer_size = bytes_received_size;
-  }
-  size_t offset = 0;
-  for (i = 0; i < h->args->read_buffer->count; i++) {
-    size_t slice_size = GPR_SLICE_LENGTH(h->args->read_buffer->slices[i]);
-    memcpy(h->handshake_buffer + offset,
-           GRPC_SLICE_START_PTR(h->args->read_buffer->slices[i]), slice_size);
-    offset += slice_size;
-  }
+  size_t bytes_received_size =
+      move_read_buffer_into_handshake_buffer(exec_ctx, h);
   // Call TSI handshaker.
   error = do_handshaker_next_locked(exec_ctx, h, h->handshake_buffer,
                                     bytes_received_size);
@@ -403,7 +405,10 @@ static void security_handshaker_do_handshake(grpc_exec_ctx *exec_ctx,
   h->args = args;
   h->on_handshake_done = on_handshake_done;
   gpr_ref(&h->refs);
-  grpc_error *error = do_handshaker_next_locked(exec_ctx, h, NULL, 0);
+  size_t bytes_received_size =
+      move_read_buffer_into_handshake_buffer(exec_ctx, h);
+  grpc_error *error = do_handshaker_next_locked(
+      exec_ctx, h, h->handshake_buffer, bytes_received_size);
   if (error != GRPC_ERROR_NONE) {
     security_handshake_failed_locked(exec_ctx, h, error);
     gpr_mu_unlock(&h->mu);
diff --git a/test/core/handshake/readahead_handshaker_server_ssl.c b/test/core/handshake/readahead_handshaker_server_ssl.c
new file mode 100644
index 0000000000..f25c35615c
--- /dev/null
+++ b/test/core/handshake/readahead_handshaker_server_ssl.c
@@ -0,0 +1,103 @@
+/*
+ *
+ * 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 <arpa/inet.h>
+#include <openssl/err.h>
+#include <openssl/ssl.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+#include <grpc/grpc.h>
+#include <grpc/grpc_security.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/sync.h>
+#include <grpc/support/thd.h>
+#include "src/core/lib/iomgr/load_file.h"
+#include "test/core/util/port.h"
+#include "test/core/util/test_config.h"
+
+#include "src/core/lib/channel/handshaker_factory.h"
+#include "src/core/lib/channel/handshaker_registry.h"
+#include "src/core/lib/security/transport/security_handshaker.h"
+
+#include "test/core/handshake/server_ssl_common.h"
+
+/* The purpose of this test is to exercise the case when a
+ * grpc *security_handshaker* begins its handshake with data already
+ * in the read buffer of the handshaker arg. This scenario is created by
+ * adding a fake "readahead" handshaker at the beginning of the server's
+ * handshaker list, which just reads from the connection and then places
+ * read bytes into the read buffer of the handshake arg (to be passed down
+ * to the security_handshaker). This test is meant to protect code relying on
+ * this functionality that lives outside of this repo. */
+
+static void readahead_handshaker_destroy(grpc_exec_ctx *ctx,
+                                         grpc_handshaker *handshaker) {
+  gpr_free(handshaker);
+}
+
+static void readahead_handshaker_shutdown(grpc_exec_ctx *ctx,
+                                          grpc_handshaker *handshaker,
+                                          grpc_error *error) {}
+
+static void readahead_handshaker_do_handshake(
+    grpc_exec_ctx *ctx, grpc_handshaker *handshaker,
+    grpc_tcp_server_acceptor *acceptor, grpc_closure *on_handshake_done,
+    grpc_handshaker_args *args) {
+  grpc_endpoint_read(ctx, args->endpoint, args->read_buffer, on_handshake_done);
+}
+
+const grpc_handshaker_vtable readahead_handshaker_vtable = {
+    readahead_handshaker_destroy, readahead_handshaker_shutdown,
+    readahead_handshaker_do_handshake};
+
+static grpc_handshaker *readahead_handshaker_create(grpc_exec_ctx *ctx) {
+  grpc_handshaker *h = (grpc_handshaker *)gpr_zalloc(sizeof(grpc_handshaker));
+  grpc_handshaker_init(&readahead_handshaker_vtable, h);
+  return h;
+}
+
+static void readahead_handshaker_factory_add_handshakers(
+    grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *hf,
+    const grpc_channel_args *args, grpc_handshake_manager *handshake_mgr) {
+  grpc_handshake_manager_add(handshake_mgr,
+                             readahead_handshaker_create(exec_ctx));
+}
+
+static void readahead_handshaker_factory_destroy(
+    grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *handshaker_factory) {}
+
+static const grpc_handshaker_factory_vtable
+    readahead_handshaker_factory_vtable = {
+        readahead_handshaker_factory_add_handshakers,
+        readahead_handshaker_factory_destroy};
+
+int main(int argc, char *argv[]) {
+  grpc_handshaker_factory readahead_handshaker_factory = {
+      &readahead_handshaker_factory_vtable};
+  grpc_init();
+  grpc_handshaker_factory_register(true /* at_start */, HANDSHAKER_SERVER,
+                                   &readahead_handshaker_factory);
+  const char *full_alpn_list[] = {"grpc-exp", "h2"};
+  GPR_ASSERT(server_ssl_test(full_alpn_list, 2, "grpc-exp"));
+  grpc_shutdown();
+  return 0;
+}
diff --git a/test/core/handshake/server_ssl.c b/test/core/handshake/server_ssl.c
index 85a8b4de41..8b96076338 100644
--- a/test/core/handshake/server_ssl.c
+++ b/test/core/handshake/server_ssl.c
@@ -34,205 +34,7 @@
 #include "test/core/util/port.h"
 #include "test/core/util/test_config.h"
 
-#define SSL_CERT_PATH "src/core/tsi/test_creds/server1.pem"
-#define SSL_KEY_PATH "src/core/tsi/test_creds/server1.key"
-#define SSL_CA_PATH "src/core/tsi/test_creds/ca.pem"
-
-// Handshake completed signal to server thread.
-static gpr_event client_handshake_complete;
-
-static int create_socket(int port) {
-  int s;
-  struct sockaddr_in addr;
-
-  addr.sin_family = AF_INET;
-  addr.sin_port = htons((uint16_t)port);
-  addr.sin_addr.s_addr = htonl(INADDR_ANY);
-
-  s = socket(AF_INET, SOCK_STREAM, 0);
-  if (s < 0) {
-    perror("Unable to create socket");
-    return -1;
-  }
-
-  if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
-    perror("Unable to connect");
-    return -1;
-  }
-
-  return s;
-}
-
-// Simple gRPC server. This listens until client_handshake_complete occurs.
-static void server_thread(void *arg) {
-  const int port = *(int *)arg;
-
-  // Load key pair and establish server SSL credentials.
-  grpc_ssl_pem_key_cert_pair pem_key_cert_pair;
-  grpc_slice ca_slice, cert_slice, key_slice;
-  GPR_ASSERT(GRPC_LOG_IF_ERROR("load_file",
-                               grpc_load_file(SSL_CA_PATH, 1, &ca_slice)));
-  GPR_ASSERT(GRPC_LOG_IF_ERROR("load_file",
-                               grpc_load_file(SSL_CERT_PATH, 1, &cert_slice)));
-  GPR_ASSERT(GRPC_LOG_IF_ERROR("load_file",
-                               grpc_load_file(SSL_KEY_PATH, 1, &key_slice)));
-  const char *ca_cert = (const char *)GRPC_SLICE_START_PTR(ca_slice);
-  pem_key_cert_pair.private_key = (const char *)GRPC_SLICE_START_PTR(key_slice);
-  pem_key_cert_pair.cert_chain = (const char *)GRPC_SLICE_START_PTR(cert_slice);
-  grpc_server_credentials *ssl_creds = grpc_ssl_server_credentials_create(
-      ca_cert, &pem_key_cert_pair, 1, 0, NULL);
-
-  // Start server listening on local port.
-  char *addr;
-  gpr_asprintf(&addr, "127.0.0.1:%d", port);
-  grpc_server *server = grpc_server_create(NULL, NULL);
-  GPR_ASSERT(grpc_server_add_secure_http2_port(server, addr, ssl_creds));
-  free(addr);
-
-  grpc_completion_queue *cq = grpc_completion_queue_create_for_next(NULL);
-
-  grpc_server_register_completion_queue(server, cq, NULL);
-  grpc_server_start(server);
-
-  // Wait a bounded number of time until client_handshake_complete is set,
-  // sleeping between polls.
-  int retries = 10;
-  while (!gpr_event_get(&client_handshake_complete) && retries-- > 0) {
-    const gpr_timespec cq_deadline = grpc_timeout_seconds_to_deadline(1);
-    grpc_event ev = grpc_completion_queue_next(cq, cq_deadline, NULL);
-    GPR_ASSERT(ev.type == GRPC_QUEUE_TIMEOUT);
-  }
-
-  gpr_log(GPR_INFO, "Shutting down server");
-  grpc_server_shutdown_and_notify(server, cq, NULL);
-  grpc_completion_queue_shutdown(cq);
-
-  const gpr_timespec cq_deadline = grpc_timeout_seconds_to_deadline(5);
-  grpc_event ev = grpc_completion_queue_next(cq, cq_deadline, NULL);
-  GPR_ASSERT(ev.type == GRPC_OP_COMPLETE);
-
-  grpc_server_destroy(server);
-  grpc_completion_queue_destroy(cq);
-  grpc_server_credentials_release(ssl_creds);
-  grpc_slice_unref(cert_slice);
-  grpc_slice_unref(key_slice);
-  grpc_slice_unref(ca_slice);
-}
-
-// This test launches a gRPC server on a separate thread and then establishes a
-// TLS handshake via a minimal TLS client. The TLS client has configurable (via
-// alpn_list) ALPN settings and can probe at the supported ALPN preferences
-// using this (via alpn_expected).
-static bool server_ssl_test(const char *alpn_list[], unsigned int alpn_list_len,
-                            const char *alpn_expected) {
-  bool success = true;
-
-  grpc_init();
-  int port = grpc_pick_unused_port_or_die();
-  gpr_event_init(&client_handshake_complete);
-
-  // Launch the gRPC server thread.
-  gpr_thd_options thdopt = gpr_thd_options_default();
-  gpr_thd_id thdid;
-  gpr_thd_options_set_joinable(&thdopt);
-  GPR_ASSERT(gpr_thd_new(&thdid, server_thread, &port, &thdopt));
-
-  SSL_load_error_strings();
-  OpenSSL_add_ssl_algorithms();
-
-  const SSL_METHOD *method = TLSv1_2_client_method();
-  SSL_CTX *ctx = SSL_CTX_new(method);
-  if (!ctx) {
-    perror("Unable to create SSL context");
-    ERR_print_errors_fp(stderr);
-    abort();
-  }
-
-  // Load key pair.
-  if (SSL_CTX_use_certificate_file(ctx, SSL_CERT_PATH, SSL_FILETYPE_PEM) < 0) {
-    ERR_print_errors_fp(stderr);
-    abort();
-  }
-  if (SSL_CTX_use_PrivateKey_file(ctx, SSL_KEY_PATH, SSL_FILETYPE_PEM) < 0) {
-    ERR_print_errors_fp(stderr);
-    abort();
-  }
-
-  // Set the cipher list to match the one expressed in
-  // src/core/tsi/ssl_transport_security.c.
-  const char *cipher_list =
-      "ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-"
-      "SHA384:ECDHE-RSA-AES256-GCM-SHA384";
-  if (!SSL_CTX_set_cipher_list(ctx, cipher_list)) {
-    ERR_print_errors_fp(stderr);
-    gpr_log(GPR_ERROR, "Couldn't set server cipher list.");
-    abort();
-  }
-
-  // Configure ALPN list the client will send to the server. This must match the
-  // wire format, see documentation for SSL_CTX_set_alpn_protos.
-  unsigned int alpn_protos_len = alpn_list_len;
-  for (unsigned int i = 0; i < alpn_list_len; ++i) {
-    alpn_protos_len += (unsigned int)strlen(alpn_list[i]);
-  }
-  unsigned char *alpn_protos = gpr_malloc(alpn_protos_len);
-  unsigned char *p = alpn_protos;
-  for (unsigned int i = 0; i < alpn_list_len; ++i) {
-    const uint8_t len = (uint8_t)strlen(alpn_list[i]);
-    *p++ = len;
-    memcpy(p, alpn_list[i], len);
-    p += len;
-  }
-  GPR_ASSERT(SSL_CTX_set_alpn_protos(ctx, alpn_protos, alpn_protos_len) == 0);
-
-  // Try and connect to server. We allow a bounded number of retries as we might
-  // be racing with the server setup on its separate thread.
-  int retries = 10;
-  int sock = -1;
-  while (sock == -1 && retries-- > 0) {
-    sock = create_socket(port);
-    if (sock < 0) {
-      sleep(1);
-    }
-  }
-  GPR_ASSERT(sock > 0);
-  gpr_log(GPR_INFO, "Connected to server on port %d", port);
-
-  // Establish a SSL* and connect at SSL layer.
-  SSL *ssl = SSL_new(ctx);
-  GPR_ASSERT(ssl);
-  SSL_set_fd(ssl, sock);
-  if (SSL_connect(ssl) <= 0) {
-    ERR_print_errors_fp(stderr);
-    gpr_log(GPR_ERROR, "Handshake failed.");
-    success = false;
-  } else {
-    gpr_log(GPR_INFO, "Handshake successful.");
-    // Validate ALPN preferred by server matches alpn_expected.
-    const unsigned char *alpn_selected;
-    unsigned int alpn_selected_len;
-    SSL_get0_alpn_selected(ssl, &alpn_selected, &alpn_selected_len);
-    if (strlen(alpn_expected) != alpn_selected_len ||
-        strncmp((const char *)alpn_selected, alpn_expected,
-                alpn_selected_len) != 0) {
-      gpr_log(GPR_ERROR, "Unexpected ALPN protocol preference");
-      success = false;
-    }
-  }
-  gpr_event_set(&client_handshake_complete, &client_handshake_complete);
-
-  SSL_free(ssl);
-  gpr_free(alpn_protos);
-  SSL_CTX_free(ctx);
-  EVP_cleanup();
-  close(sock);
-
-  gpr_thd_join(thdid);
-
-  grpc_shutdown();
-
-  return success;
-}
+#include "test/core/handshake/server_ssl_common.h"
 
 int main(int argc, char *argv[]) {
   // Handshake succeeeds when the client supplies the standard ALPN list.
diff --git a/test/core/handshake/server_ssl_common.c b/test/core/handshake/server_ssl_common.c
new file mode 100644
index 0000000000..d1911ecfde
--- /dev/null
+++ b/test/core/handshake/server_ssl_common.c
@@ -0,0 +1,237 @@
+/*
+ *
+ * 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/handshake/server_ssl_common.h"
+
+#include <arpa/inet.h>
+#include <openssl/err.h>
+#include <openssl/ssl.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+#include <grpc/grpc.h>
+#include <grpc/grpc_security.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/sync.h>
+#include <grpc/support/thd.h>
+#include "src/core/lib/iomgr/load_file.h"
+#include "test/core/util/port.h"
+#include "test/core/util/test_config.h"
+
+#define SSL_CERT_PATH "src/core/tsi/test_creds/server1.pem"
+#define SSL_KEY_PATH "src/core/tsi/test_creds/server1.key"
+#define SSL_CA_PATH "src/core/tsi/test_creds/ca.pem"
+
+// Handshake completed signal to server thread.
+static gpr_event client_handshake_complete;
+
+static int create_socket(int port) {
+  int s;
+  struct sockaddr_in addr;
+
+  addr.sin_family = AF_INET;
+  addr.sin_port = htons((uint16_t)port);
+  addr.sin_addr.s_addr = htonl(INADDR_ANY);
+
+  s = socket(AF_INET, SOCK_STREAM, 0);
+  if (s < 0) {
+    perror("Unable to create socket");
+    return -1;
+  }
+
+  if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
+    perror("Unable to connect");
+    return -1;
+  }
+
+  return s;
+}
+
+// Simple gRPC server. This listens until client_handshake_complete occurs.
+static void server_thread(void *arg) {
+  const int port = *(int *)arg;
+
+  // Load key pair and establish server SSL credentials.
+  grpc_ssl_pem_key_cert_pair pem_key_cert_pair;
+  grpc_slice ca_slice, cert_slice, key_slice;
+  GPR_ASSERT(GRPC_LOG_IF_ERROR("load_file",
+                               grpc_load_file(SSL_CA_PATH, 1, &ca_slice)));
+  GPR_ASSERT(GRPC_LOG_IF_ERROR("load_file",
+                               grpc_load_file(SSL_CERT_PATH, 1, &cert_slice)));
+  GPR_ASSERT(GRPC_LOG_IF_ERROR("load_file",
+                               grpc_load_file(SSL_KEY_PATH, 1, &key_slice)));
+  const char *ca_cert = (const char *)GRPC_SLICE_START_PTR(ca_slice);
+  pem_key_cert_pair.private_key = (const char *)GRPC_SLICE_START_PTR(key_slice);
+  pem_key_cert_pair.cert_chain = (const char *)GRPC_SLICE_START_PTR(cert_slice);
+  grpc_server_credentials *ssl_creds = grpc_ssl_server_credentials_create(
+      ca_cert, &pem_key_cert_pair, 1, 0, NULL);
+
+  // Start server listening on local port.
+  char *addr;
+  gpr_asprintf(&addr, "127.0.0.1:%d", port);
+  grpc_server *server = grpc_server_create(NULL, NULL);
+  GPR_ASSERT(grpc_server_add_secure_http2_port(server, addr, ssl_creds));
+  free(addr);
+
+  grpc_completion_queue *cq = grpc_completion_queue_create_for_next(NULL);
+
+  grpc_server_register_completion_queue(server, cq, NULL);
+  grpc_server_start(server);
+
+  // Wait a bounded number of time until client_handshake_complete is set,
+  // sleeping between polls.
+  int retries = 10;
+  while (!gpr_event_get(&client_handshake_complete) && retries-- > 0) {
+    const gpr_timespec cq_deadline = grpc_timeout_seconds_to_deadline(1);
+    grpc_event ev = grpc_completion_queue_next(cq, cq_deadline, NULL);
+    GPR_ASSERT(ev.type == GRPC_QUEUE_TIMEOUT);
+  }
+
+  gpr_log(GPR_INFO, "Shutting down server");
+  grpc_server_shutdown_and_notify(server, cq, NULL);
+  grpc_completion_queue_shutdown(cq);
+
+  const gpr_timespec cq_deadline = grpc_timeout_seconds_to_deadline(5);
+  grpc_event ev = grpc_completion_queue_next(cq, cq_deadline, NULL);
+  GPR_ASSERT(ev.type == GRPC_OP_COMPLETE);
+
+  grpc_server_destroy(server);
+  grpc_completion_queue_destroy(cq);
+  grpc_server_credentials_release(ssl_creds);
+  grpc_slice_unref(cert_slice);
+  grpc_slice_unref(key_slice);
+  grpc_slice_unref(ca_slice);
+}
+
+// This test launches a gRPC server on a separate thread and then establishes a
+// TLS handshake via a minimal TLS client. The TLS client has configurable (via
+// alpn_list) ALPN settings and can probe at the supported ALPN preferences
+// using this (via alpn_expected).
+bool server_ssl_test(const char *alpn_list[], unsigned int alpn_list_len,
+                     const char *alpn_expected) {
+  bool success = true;
+
+  grpc_init();
+  int port = grpc_pick_unused_port_or_die();
+  gpr_event_init(&client_handshake_complete);
+
+  // Launch the gRPC server thread.
+  gpr_thd_options thdopt = gpr_thd_options_default();
+  gpr_thd_id thdid;
+  gpr_thd_options_set_joinable(&thdopt);
+  GPR_ASSERT(gpr_thd_new(&thdid, server_thread, &port, &thdopt));
+
+  SSL_load_error_strings();
+  OpenSSL_add_ssl_algorithms();
+
+  const SSL_METHOD *method = TLSv1_2_client_method();
+  SSL_CTX *ctx = SSL_CTX_new(method);
+  if (!ctx) {
+    perror("Unable to create SSL context");
+    ERR_print_errors_fp(stderr);
+    abort();
+  }
+
+  // Load key pair.
+  if (SSL_CTX_use_certificate_file(ctx, SSL_CERT_PATH, SSL_FILETYPE_PEM) < 0) {
+    ERR_print_errors_fp(stderr);
+    abort();
+  }
+  if (SSL_CTX_use_PrivateKey_file(ctx, SSL_KEY_PATH, SSL_FILETYPE_PEM) < 0) {
+    ERR_print_errors_fp(stderr);
+    abort();
+  }
+
+  // Set the cipher list to match the one expressed in
+  // src/core/tsi/ssl_transport_security.c.
+  const char *cipher_list =
+      "ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-"
+      "SHA384:ECDHE-RSA-AES256-GCM-SHA384";
+  if (!SSL_CTX_set_cipher_list(ctx, cipher_list)) {
+    ERR_print_errors_fp(stderr);
+    gpr_log(GPR_ERROR, "Couldn't set server cipher list.");
+    abort();
+  }
+
+  // Configure ALPN list the client will send to the server. This must match the
+  // wire format, see documentation for SSL_CTX_set_alpn_protos.
+  unsigned int alpn_protos_len = alpn_list_len;
+  for (unsigned int i = 0; i < alpn_list_len; ++i) {
+    alpn_protos_len += (unsigned int)strlen(alpn_list[i]);
+  }
+  unsigned char *alpn_protos = gpr_malloc(alpn_protos_len);
+  unsigned char *p = alpn_protos;
+  for (unsigned int i = 0; i < alpn_list_len; ++i) {
+    const uint8_t len = (uint8_t)strlen(alpn_list[i]);
+    *p++ = len;
+    memcpy(p, alpn_list[i], len);
+    p += len;
+  }
+  GPR_ASSERT(SSL_CTX_set_alpn_protos(ctx, alpn_protos, alpn_protos_len) == 0);
+
+  // Try and connect to server. We allow a bounded number of retries as we might
+  // be racing with the server setup on its separate thread.
+  int retries = 10;
+  int sock = -1;
+  while (sock == -1 && retries-- > 0) {
+    sock = create_socket(port);
+    if (sock < 0) {
+      sleep(1);
+    }
+  }
+  GPR_ASSERT(sock > 0);
+  gpr_log(GPR_INFO, "Connected to server on port %d", port);
+
+  // Establish a SSL* and connect at SSL layer.
+  SSL *ssl = SSL_new(ctx);
+  GPR_ASSERT(ssl);
+  SSL_set_fd(ssl, sock);
+  if (SSL_connect(ssl) <= 0) {
+    ERR_print_errors_fp(stderr);
+    gpr_log(GPR_ERROR, "Handshake failed.");
+    success = false;
+  } else {
+    gpr_log(GPR_INFO, "Handshake successful.");
+    // Validate ALPN preferred by server matches alpn_expected.
+    const unsigned char *alpn_selected;
+    unsigned int alpn_selected_len;
+    SSL_get0_alpn_selected(ssl, &alpn_selected, &alpn_selected_len);
+    if (strlen(alpn_expected) != alpn_selected_len ||
+        strncmp((const char *)alpn_selected, alpn_expected,
+                alpn_selected_len) != 0) {
+      gpr_log(GPR_ERROR, "Unexpected ALPN protocol preference");
+      success = false;
+    }
+  }
+  gpr_event_set(&client_handshake_complete, &client_handshake_complete);
+
+  SSL_free(ssl);
+  gpr_free(alpn_protos);
+  SSL_CTX_free(ctx);
+  EVP_cleanup();
+  close(sock);
+
+  gpr_thd_join(thdid);
+
+  grpc_shutdown();
+
+  return success;
+}
diff --git a/test/core/handshake/server_ssl_common.h b/test/core/handshake/server_ssl_common.h
new file mode 100644
index 0000000000..67b323d82f
--- /dev/null
+++ b/test/core/handshake/server_ssl_common.h
@@ -0,0 +1,22 @@
+//
+// Created by apolcyn on 10/31/17.
+//
+
+#ifndef GRPC_SERVER_SSL_COMMON_H
+#define GRPC_SERVER_SSL_COMMON_H
+
+#include <grpc/grpc.h>
+#include <grpc/grpc_security.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/sync.h>
+#include <grpc/support/thd.h>
+#include "src/core/lib/iomgr/load_file.h"
+#include "test/core/util/port.h"
+#include "test/core/util/test_config.h"
+
+bool server_ssl_test(const char *alpn_list[], unsigned int alpn_list_len,
+                     const char *alpn_expected);
+
+#endif  // GRPC_SERVER_SSL_COMMON_H
diff --git a/tools/run_tests/generated/sources_and_headers.json b/tools/run_tests/generated/sources_and_headers.json
index 46f4cb6532..9f5e39e054 100644
--- a/tools/run_tests/generated/sources_and_headers.json
+++ b/tools/run_tests/generated/sources_and_headers.json
@@ -1280,7 +1280,26 @@
     "language": "c", 
     "name": "handshake_server", 
     "src": [
-      "test/core/handshake/server_ssl.c"
+      "test/core/handshake/server_ssl.c", 
+      "test/core/handshake/server_ssl_common.c"
+    ], 
+    "third_party": false, 
+    "type": "target"
+  }, 
+  {
+    "deps": [
+      "gpr", 
+      "gpr_test_util", 
+      "grpc", 
+      "grpc_test_util"
+    ], 
+    "headers": [], 
+    "is_filegroup": false, 
+    "language": "c", 
+    "name": "handshake_server_with_readahead_handshaker", 
+    "src": [
+      "test/core/handshake/readahead_handshaker_server_ssl.c", 
+      "test/core/handshake/server_ssl_common.c"
     ], 
     "third_party": false, 
     "type": "target"
diff --git a/tools/run_tests/generated/tests.json b/tools/run_tests/generated/tests.json
index 3b1b6587f6..7f197b4ba0 100644
--- a/tools/run_tests/generated/tests.json
+++ b/tools/run_tests/generated/tests.json
@@ -1603,6 +1603,26 @@
     "args": [], 
     "benchmark": false, 
     "ci_platforms": [
+      "linux"
+    ], 
+    "cpu_cost": 1.0, 
+    "exclude_configs": [], 
+    "exclude_iomgrs": [
+      "uv"
+    ], 
+    "flaky": false, 
+    "gtest": false, 
+    "language": "c", 
+    "name": "handshake_server_with_readahead_handshaker", 
+    "platforms": [
+      "linux"
+    ], 
+    "uses_polling": true
+  }, 
+  {
+    "args": [], 
+    "benchmark": false, 
+    "ci_platforms": [
       "linux", 
       "mac", 
       "posix",