Merge github.com:grpc/grpc into fix_errors

46 files changed, 565 insertions, 243 deletions

diff --git a/BUILD b/BUILD
index a756f5ac62..75ce780d16 100644
--- a/BUILD
+++ b/BUILD
@@ -421,6 +421,8 @@ grpc_cc_library(
         "src/core/lib/channel/connected_channel.c",
         "src/core/lib/channel/deadline_filter.c",
         "src/core/lib/channel/handshaker.c",
+        "src/core/lib/channel/handshaker_factory.c",
+        "src/core/lib/channel/handshaker_registry.c",
         "src/core/lib/channel/http_client_filter.c",
         "src/core/lib/channel/http_server_filter.c",
         "src/core/lib/channel/message_size_filter.c",
@@ -539,6 +541,8 @@ grpc_cc_library(
         "src/core/lib/channel/context.h",
         "src/core/lib/channel/deadline_filter.h",
         "src/core/lib/channel/handshaker.h",
+        "src/core/lib/channel/handshaker_factory.h",
+        "src/core/lib/channel/handshaker_registry.h",
         "src/core/lib/channel/http_client_filter.h",
         "src/core/lib/channel/http_server_filter.h",
         "src/core/lib/channel/message_size_filter.h",
diff --git a/CMakeLists.txt b/CMakeLists.txt
index f406e11f34..5dc0162ca2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -292,6 +292,8 @@ add_library(grpc
   src/core/lib/channel/connected_channel.c
   src/core/lib/channel/deadline_filter.c
   src/core/lib/channel/handshaker.c
+  src/core/lib/channel/handshaker_factory.c
+  src/core/lib/channel/handshaker_registry.c
   src/core/lib/channel/http_client_filter.c
   src/core/lib/channel/http_server_filter.c
   src/core/lib/channel/message_size_filter.c
@@ -576,6 +578,8 @@ add_library(grpc_cronet
   src/core/lib/channel/connected_channel.c
   src/core/lib/channel/deadline_filter.c
   src/core/lib/channel/handshaker.c
+  src/core/lib/channel/handshaker_factory.c
+  src/core/lib/channel/handshaker_registry.c
   src/core/lib/channel/http_client_filter.c
   src/core/lib/channel/http_server_filter.c
   src/core/lib/channel/message_size_filter.c
@@ -831,6 +835,8 @@ add_library(grpc_unsecure
   src/core/lib/channel/connected_channel.c
   src/core/lib/channel/deadline_filter.c
   src/core/lib/channel/handshaker.c
+  src/core/lib/channel/handshaker_factory.c
+  src/core/lib/channel/handshaker_registry.c
   src/core/lib/channel/http_client_filter.c
   src/core/lib/channel/http_server_filter.c
   src/core/lib/channel/message_size_filter.c
@@ -1301,6 +1307,8 @@ add_library(grpc++_cronet
   src/core/lib/channel/connected_channel.c
   src/core/lib/channel/deadline_filter.c
   src/core/lib/channel/handshaker.c
+  src/core/lib/channel/handshaker_factory.c
+  src/core/lib/channel/handshaker_registry.c
   src/core/lib/channel/http_client_filter.c
   src/core/lib/channel/http_server_filter.c
   src/core/lib/channel/message_size_filter.c
diff --git a/Makefile b/Makefile
index 0b2bc0c692..bc2be439ac 100644
--- a/Makefile
+++ b/Makefile
@@ -2631,6 +2631,8 @@ LIBGRPC_SRC = \
     src/core/lib/channel/connected_channel.c \
     src/core/lib/channel/deadline_filter.c \
     src/core/lib/channel/handshaker.c \
+    src/core/lib/channel/handshaker_factory.c \
+    src/core/lib/channel/handshaker_registry.c \
     src/core/lib/channel/http_client_filter.c \
     src/core/lib/channel/http_server_filter.c \
     src/core/lib/channel/message_size_filter.c \
@@ -2933,6 +2935,8 @@ LIBGRPC_CRONET_SRC = \
     src/core/lib/channel/connected_channel.c \
     src/core/lib/channel/deadline_filter.c \
     src/core/lib/channel/handshaker.c \
+    src/core/lib/channel/handshaker_factory.c \
+    src/core/lib/channel/handshaker_registry.c \
     src/core/lib/channel/http_client_filter.c \
     src/core/lib/channel/http_server_filter.c \
     src/core/lib/channel/message_size_filter.c \
@@ -3225,6 +3229,8 @@ LIBGRPC_TEST_UTIL_SRC = \
     src/core/lib/channel/connected_channel.c \
     src/core/lib/channel/deadline_filter.c \
     src/core/lib/channel/handshaker.c \
+    src/core/lib/channel/handshaker_factory.c \
+    src/core/lib/channel/handshaker_registry.c \
     src/core/lib/channel/http_client_filter.c \
     src/core/lib/channel/http_server_filter.c \
     src/core/lib/channel/message_size_filter.c \
@@ -3446,6 +3452,8 @@ LIBGRPC_UNSECURE_SRC = \
     src/core/lib/channel/connected_channel.c \
     src/core/lib/channel/deadline_filter.c \
     src/core/lib/channel/handshaker.c \
+    src/core/lib/channel/handshaker_factory.c \
+    src/core/lib/channel/handshaker_registry.c \
     src/core/lib/channel/http_client_filter.c \
     src/core/lib/channel/http_server_filter.c \
     src/core/lib/channel/message_size_filter.c \
@@ -4028,6 +4036,8 @@ LIBGRPC++_CRONET_SRC = \
     src/core/lib/channel/connected_channel.c \
     src/core/lib/channel/deadline_filter.c \
     src/core/lib/channel/handshaker.c \
+    src/core/lib/channel/handshaker_factory.c \
+    src/core/lib/channel/handshaker_registry.c \
     src/core/lib/channel/http_client_filter.c \
     src/core/lib/channel/http_server_filter.c \
     src/core/lib/channel/message_size_filter.c \
diff --git a/binding.gyp b/binding.gyp
index 296fb4e43a..ce50f58ccd 100644
--- a/binding.gyp
+++ b/binding.gyp
@@ -572,6 +572,8 @@
         'src/core/lib/channel/connected_channel.c',
         'src/core/lib/channel/deadline_filter.c',
         'src/core/lib/channel/handshaker.c',
+        'src/core/lib/channel/handshaker_factory.c',
+        'src/core/lib/channel/handshaker_registry.c',
         'src/core/lib/channel/http_client_filter.c',
         'src/core/lib/channel/http_server_filter.c',
         'src/core/lib/channel/message_size_filter.c',
diff --git a/build.yaml b/build.yaml
index ab23c8080f..94cb53fcfa 100644
--- a/build.yaml
+++ b/build.yaml
@@ -171,6 +171,8 @@ filegroups:
   - src/core/lib/channel/context.h
   - src/core/lib/channel/deadline_filter.h
   - src/core/lib/channel/handshaker.h
+  - src/core/lib/channel/handshaker_factory.h
+  - src/core/lib/channel/handshaker_registry.h
   - src/core/lib/channel/http_client_filter.h
   - src/core/lib/channel/http_server_filter.h
   - src/core/lib/channel/message_size_filter.h
@@ -273,6 +275,8 @@ filegroups:
   - src/core/lib/channel/connected_channel.c
   - src/core/lib/channel/deadline_filter.c
   - src/core/lib/channel/handshaker.c
+  - src/core/lib/channel/handshaker_factory.c
+  - src/core/lib/channel/handshaker_registry.c
   - src/core/lib/channel/http_client_filter.c
   - src/core/lib/channel/http_server_filter.c
   - src/core/lib/channel/message_size_filter.c
diff --git a/config.m4 b/config.m4
index 4c30d11c26..e5ad3cf603 100644
--- a/config.m4
+++ b/config.m4
@@ -88,6 +88,8 @@ if test "$PHP_GRPC" != "no"; then
     src/core/lib/channel/connected_channel.c \
     src/core/lib/channel/deadline_filter.c \
     src/core/lib/channel/handshaker.c \
+    src/core/lib/channel/handshaker_factory.c \
+    src/core/lib/channel/handshaker_registry.c \
     src/core/lib/channel/http_client_filter.c \
     src/core/lib/channel/http_server_filter.c \
     src/core/lib/channel/message_size_filter.c \
diff --git a/gRPC-Core.podspec b/gRPC-Core.podspec
index 6606185668..718ca095a2 100644
--- a/gRPC-Core.podspec
+++ b/gRPC-Core.podspec
@@ -256,6 +256,8 @@ Pod::Spec.new do |s|
                       'src/core/lib/channel/context.h',
                       'src/core/lib/channel/deadline_filter.h',
                       'src/core/lib/channel/handshaker.h',
+                      'src/core/lib/channel/handshaker_factory.h',
+                      'src/core/lib/channel/handshaker_registry.h',
                       'src/core/lib/channel/http_client_filter.h',
                       'src/core/lib/channel/http_server_filter.h',
                       'src/core/lib/channel/message_size_filter.h',
@@ -438,6 +440,8 @@ Pod::Spec.new do |s|
                       'src/core/lib/channel/connected_channel.c',
                       'src/core/lib/channel/deadline_filter.c',
                       'src/core/lib/channel/handshaker.c',
+                      'src/core/lib/channel/handshaker_factory.c',
+                      'src/core/lib/channel/handshaker_registry.c',
                       'src/core/lib/channel/http_client_filter.c',
                       'src/core/lib/channel/http_server_filter.c',
                       'src/core/lib/channel/message_size_filter.c',
@@ -668,6 +672,8 @@ Pod::Spec.new do |s|
                               'src/core/lib/channel/context.h',
                               'src/core/lib/channel/deadline_filter.h',
                               'src/core/lib/channel/handshaker.h',
+                              'src/core/lib/channel/handshaker_factory.h',
+                              'src/core/lib/channel/handshaker_registry.h',
                               'src/core/lib/channel/http_client_filter.h',
                               'src/core/lib/channel/http_server_filter.h',
                               'src/core/lib/channel/message_size_filter.h',
diff --git a/grpc.gemspec b/grpc.gemspec
index ab57b444ed..2fcc18f119 100755
--- a/grpc.gemspec
+++ b/grpc.gemspec
@@ -173,6 +173,8 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/lib/channel/context.h )
   s.files += %w( src/core/lib/channel/deadline_filter.h )
   s.files += %w( src/core/lib/channel/handshaker.h )
+  s.files += %w( src/core/lib/channel/handshaker_factory.h )
+  s.files += %w( src/core/lib/channel/handshaker_registry.h )
   s.files += %w( src/core/lib/channel/http_client_filter.h )
   s.files += %w( src/core/lib/channel/http_server_filter.h )
   s.files += %w( src/core/lib/channel/message_size_filter.h )
@@ -355,6 +357,8 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/lib/channel/connected_channel.c )
   s.files += %w( src/core/lib/channel/deadline_filter.c )
   s.files += %w( src/core/lib/channel/handshaker.c )
+  s.files += %w( src/core/lib/channel/handshaker_factory.c )
+  s.files += %w( src/core/lib/channel/handshaker_registry.c )
   s.files += %w( src/core/lib/channel/http_client_filter.c )
   s.files += %w( src/core/lib/channel/http_server_filter.c )
   s.files += %w( src/core/lib/channel/message_size_filter.c )
diff --git a/package.xml b/package.xml
index 3313ead9e2..778178380b 100644
--- a/package.xml
+++ b/package.xml
@@ -181,6 +181,8 @@
     <file baseinstalldir="/" name="src/core/lib/channel/context.h" role="src" />
     <file baseinstalldir="/" name="src/core/lib/channel/deadline_filter.h" role="src" />
     <file baseinstalldir="/" name="src/core/lib/channel/handshaker.h" role="src" />
+    <file baseinstalldir="/" name="src/core/lib/channel/handshaker_factory.h" role="src" />
+    <file baseinstalldir="/" name="src/core/lib/channel/handshaker_registry.h" role="src" />
     <file baseinstalldir="/" name="src/core/lib/channel/http_client_filter.h" role="src" />
     <file baseinstalldir="/" name="src/core/lib/channel/http_server_filter.h" role="src" />
     <file baseinstalldir="/" name="src/core/lib/channel/message_size_filter.h" role="src" />
@@ -363,6 +365,8 @@
     <file baseinstalldir="/" name="src/core/lib/channel/connected_channel.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/channel/deadline_filter.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/channel/handshaker.c" role="src" />
+    <file baseinstalldir="/" name="src/core/lib/channel/handshaker_factory.c" role="src" />
+    <file baseinstalldir="/" name="src/core/lib/channel/handshaker_registry.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/channel/http_client_filter.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/channel/http_server_filter.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/channel/message_size_filter.c" role="src" />
diff --git a/src/core/ext/client_channel/client_channel_plugin.c b/src/core/ext/client_channel/client_channel_plugin.c
index 988b7a1d5c..d50bba60f6 100644
--- a/src/core/ext/client_channel/client_channel_plugin.c
+++ b/src/core/ext/client_channel/client_channel_plugin.c
@@ -38,6 +38,7 @@
 #include <grpc/support/alloc.h>
 
 #include "src/core/ext/client_channel/client_channel.h"
+#include "src/core/ext/client_channel/http_connect_handshaker.h"
 #include "src/core/ext/client_channel/lb_policy_registry.h"
 #include "src/core/ext/client_channel/resolver_registry.h"
 #include "src/core/ext/client_channel/subchannel_index.h"
@@ -84,6 +85,7 @@ void grpc_client_channel_init(void) {
                                    set_default_host_if_unset, NULL);
   grpc_channel_init_register_stage(GRPC_CLIENT_CHANNEL, INT_MAX, append_filter,
                                    (void *)&grpc_client_channel_filter);
+  grpc_http_connect_register_handshaker_factory();
 }
 
 void grpc_client_channel_shutdown(void) {
diff --git a/src/core/ext/client_channel/http_connect_handshaker.c b/src/core/ext/client_channel/http_connect_handshaker.c
index 27b117af84..ace804c47f 100644
--- a/src/core/ext/client_channel/http_connect_handshaker.c
+++ b/src/core/ext/client_channel/http_connect_handshaker.c
@@ -44,6 +44,7 @@
 #include "src/core/ext/client_channel/resolver_registry.h"
 #include "src/core/ext/client_channel/uri_parser.h"
 #include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/channel/handshaker_registry.h"
 #include "src/core/lib/http/format_request.h"
 #include "src/core/lib/http/parser.h"
 #include "src/core/lib/slice/slice_internal.h"
@@ -347,3 +348,32 @@ done:
   grpc_uri_destroy(uri);
   return proxy_name;
 }
+
+//
+// handshaker factory
+//
+
+static void handshaker_factory_add_handshakers(
+    grpc_exec_ctx* exec_ctx, grpc_handshaker_factory* factory,
+    const grpc_channel_args* args, grpc_handshake_manager* handshake_mgr) {
+  char* proxy_name = grpc_get_http_proxy_server();
+  if (proxy_name != NULL) {
+    grpc_handshake_manager_add(handshake_mgr,
+                               grpc_http_connect_handshaker_create(proxy_name));
+    gpr_free(proxy_name);
+  }
+}
+
+static void handshaker_factory_destroy(grpc_exec_ctx* exec_ctx,
+                                       grpc_handshaker_factory* factory) {}
+
+static const grpc_handshaker_factory_vtable handshaker_factory_vtable = {
+    handshaker_factory_add_handshakers, handshaker_factory_destroy};
+
+static grpc_handshaker_factory handshaker_factory = {
+    &handshaker_factory_vtable};
+
+void grpc_http_connect_register_handshaker_factory() {
+  grpc_handshaker_factory_register(true /* at_start */, HANDSHAKER_CLIENT,
+                                   &handshaker_factory);
+}
diff --git a/src/core/ext/client_channel/http_connect_handshaker.h b/src/core/ext/client_channel/http_connect_handshaker.h
index ea293852e6..56485f1373 100644
--- a/src/core/ext/client_channel/http_connect_handshaker.h
+++ b/src/core/ext/client_channel/http_connect_handshaker.h
@@ -36,11 +36,14 @@
 
 #include "src/core/lib/channel/handshaker.h"
 
-/// Does NOT take ownership of \a proxy_server.
+/// Creates a new HTTP CONNECT handshaker.
 grpc_handshaker* grpc_http_connect_handshaker_create(const char* proxy_server);
 
 /// Returns the name of the proxy to use, or NULL if no proxy is configured.
 /// Caller takes ownership of result.
 char* grpc_get_http_proxy_server();
 
+/// Registers handshaker factory.
+void grpc_http_connect_register_handshaker_factory();
+
 #endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_HTTP_CONNECT_HANDSHAKER_H */
diff --git a/src/core/ext/transport/chttp2/client/chttp2_connector.c b/src/core/ext/transport/chttp2/client/chttp2_connector.c
index 2385f91dbd..2c5dfaea60 100644
--- a/src/core/ext/transport/chttp2/client/chttp2_connector.c
+++ b/src/core/ext/transport/chttp2/client/chttp2_connector.c
@@ -46,6 +46,7 @@
 #include "src/core/ext/transport/chttp2/transport/chttp2_transport.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/handshaker.h"
+#include "src/core/lib/channel/handshaker_registry.h"
 #include "src/core/lib/iomgr/tcp_client.h"
 #include "src/core/lib/slice/slice_internal.h"
 
@@ -58,9 +59,6 @@ typedef struct {
   bool shutdown;
   bool connecting;
 
-  grpc_chttp2_add_handshakers_func add_handshakers;
-  void *add_handshakers_user_data;
-
   grpc_closure *notify;
   grpc_connect_in_args args;
   grpc_connect_out_args *result;
@@ -151,16 +149,8 @@ static void on_handshake_done(grpc_exec_ctx *exec_ctx, void *arg,
 static void start_handshake_locked(grpc_exec_ctx *exec_ctx,
                                    chttp2_connector *c) {
   c->handshake_mgr = grpc_handshake_manager_create();
-  char *proxy_name = grpc_get_http_proxy_server();
-  if (proxy_name != NULL) {
-    grpc_handshake_manager_add(c->handshake_mgr,
-                               grpc_http_connect_handshaker_create(proxy_name));
-    gpr_free(proxy_name);
-  }
-  if (c->add_handshakers != NULL) {
-    c->add_handshakers(exec_ctx, c->add_handshakers_user_data,
+  grpc_handshakers_add(exec_ctx, HANDSHAKER_CLIENT, c->args.channel_args,
                        c->handshake_mgr);
-  }
   grpc_handshake_manager_do_handshake(
       exec_ctx, c->handshake_mgr, c->endpoint, c->args.channel_args,
       c->args.deadline, NULL /* acceptor */, on_handshake_done, c);
@@ -250,15 +240,11 @@ static const grpc_connector_vtable chttp2_connector_vtable = {
     chttp2_connector_ref, chttp2_connector_unref, chttp2_connector_shutdown,
     chttp2_connector_connect};
 
-grpc_connector *grpc_chttp2_connector_create(
-    grpc_exec_ctx *exec_ctx, grpc_chttp2_add_handshakers_func add_handshakers,
-    void *add_handshakers_user_data) {
+grpc_connector *grpc_chttp2_connector_create() {
   chttp2_connector *c = gpr_malloc(sizeof(*c));
   memset(c, 0, sizeof(*c));
   c->base.vtable = &chttp2_connector_vtable;
   gpr_mu_init(&c->mu);
   gpr_ref_init(&c->refs, 1);
-  c->add_handshakers = add_handshakers;
-  c->add_handshakers_user_data = add_handshakers_user_data;
   return &c->base;
 }
diff --git a/src/core/ext/transport/chttp2/client/chttp2_connector.h b/src/core/ext/transport/chttp2/client/chttp2_connector.h
index 58eba22417..f5d1025432 100644
--- a/src/core/ext/transport/chttp2/client/chttp2_connector.h
+++ b/src/core/ext/transport/chttp2/client/chttp2_connector.h
@@ -35,17 +35,7 @@
 #define GRPC_CORE_EXT_TRANSPORT_CHTTP2_CLIENT_CHTTP2_CONNECTOR_H
 
 #include "src/core/ext/client_channel/connector.h"
-#include "src/core/lib/channel/handshaker.h"
-#include "src/core/lib/iomgr/exec_ctx.h"
 
-typedef void (*grpc_chttp2_add_handshakers_func)(
-    grpc_exec_ctx* exec_ctx, void* user_data,
-    grpc_handshake_manager* handshake_mgr);
-
-/// If \a add_handshakers is non-NULL, it will be called with
-/// \a add_handshakers_user_data to add handshakers.
-grpc_connector* grpc_chttp2_connector_create(
-    grpc_exec_ctx* exec_ctx, grpc_chttp2_add_handshakers_func add_handshakers,
-    void* add_handshakers_user_data);
+grpc_connector* grpc_chttp2_connector_create();
 
 #endif /* GRPC_CORE_EXT_TRANSPORT_CHTTP2_CLIENT_CHTTP2_CONNECTOR_H */
diff --git a/src/core/ext/transport/chttp2/client/insecure/channel_create.c b/src/core/ext/transport/chttp2/client/insecure/channel_create.c
index 1d3592ef06..c9f4021216 100644
--- a/src/core/ext/transport/chttp2/client/insecure/channel_create.c
+++ b/src/core/ext/transport/chttp2/client/insecure/channel_create.c
@@ -53,8 +53,7 @@ static void client_channel_factory_unref(
 static grpc_subchannel *client_channel_factory_create_subchannel(
     grpc_exec_ctx *exec_ctx, grpc_client_channel_factory *cc_factory,
     const grpc_subchannel_args *args) {
-  grpc_connector *connector = grpc_chttp2_connector_create(
-      exec_ctx, NULL /* add_handshakers */, NULL /* user_data */);
+  grpc_connector *connector = grpc_chttp2_connector_create();
   grpc_subchannel *s = grpc_subchannel_create(exec_ctx, connector, args);
   grpc_connector_unref(exec_ctx, connector);
   return s;
@@ -96,17 +95,16 @@ grpc_channel *grpc_insecure_channel_create(const char *target,
       "grpc_insecure_channel_create(target=%p, args=%p, reserved=%p)", 3,
       (target, args, reserved));
   GPR_ASSERT(reserved == NULL);
-  grpc_client_channel_factory *factory =
-      (grpc_client_channel_factory *)&client_channel_factory;
   // Add channel arg containing the client channel factory.
-  grpc_arg arg = grpc_client_channel_factory_create_channel_arg(factory);
+  grpc_arg arg =
+      grpc_client_channel_factory_create_channel_arg(&client_channel_factory);
   grpc_channel_args *new_args = grpc_channel_args_copy_and_add(args, &arg, 1);
   // Create channel.
   grpc_channel *channel = client_channel_factory_create_channel(
-      &exec_ctx, factory, target, GRPC_CLIENT_CHANNEL_TYPE_REGULAR, new_args);
+      &exec_ctx, &client_channel_factory, target,
+      GRPC_CLIENT_CHANNEL_TYPE_REGULAR, new_args);
   // Clean up.
   grpc_channel_args_destroy(&exec_ctx, new_args);
-  grpc_client_channel_factory_unref(&exec_ctx, factory);
   grpc_exec_ctx_finish(&exec_ctx);
   return channel != NULL ? channel : grpc_lame_client_channel_create(
                                          target, GRPC_STATUS_INTERNAL,
diff --git a/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c b/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c
index 54663ef6a4..f979d9bad5 100644
--- a/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c
+++ b/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c
@@ -46,40 +46,16 @@
 #include "src/core/lib/surface/api_trace.h"
 #include "src/core/lib/surface/channel.h"
 
-typedef struct {
-  grpc_client_channel_factory base;
-  gpr_refcount refs;
-  grpc_channel_security_connector *security_connector;
-} client_channel_factory;
-
 static void client_channel_factory_ref(
-    grpc_client_channel_factory *cc_factory) {
-  client_channel_factory *f = (client_channel_factory *)cc_factory;
-  gpr_ref(&f->refs);
-}
+    grpc_client_channel_factory *cc_factory) {}
 
 static void client_channel_factory_unref(
-    grpc_exec_ctx *exec_ctx, grpc_client_channel_factory *cc_factory) {
-  client_channel_factory *f = (client_channel_factory *)cc_factory;
-  if (gpr_unref(&f->refs)) {
-    GRPC_SECURITY_CONNECTOR_UNREF(exec_ctx, &f->security_connector->base,
-                                  "client_channel_factory");
-    gpr_free(f);
-  }
-}
-
-static void add_handshakers(grpc_exec_ctx *exec_ctx, void *security_connector,
-                            grpc_handshake_manager *handshake_mgr) {
-  grpc_channel_security_connector_add_handshakers(exec_ctx, security_connector,
-                                                  handshake_mgr);
-}
+    grpc_exec_ctx *exec_ctx, grpc_client_channel_factory *cc_factory) {}
 
 static grpc_subchannel *client_channel_factory_create_subchannel(
     grpc_exec_ctx *exec_ctx, grpc_client_channel_factory *cc_factory,
     const grpc_subchannel_args *args) {
-  client_channel_factory *f = (client_channel_factory *)cc_factory;
-  grpc_connector *connector = grpc_chttp2_connector_create(
-      exec_ctx, add_handshakers, f->security_connector);
+  grpc_connector *connector = grpc_chttp2_connector_create();
   grpc_subchannel *s = grpc_subchannel_create(exec_ctx, connector, args);
   grpc_connector_unref(exec_ctx, connector);
   return s;
@@ -106,6 +82,9 @@ static const grpc_client_channel_factory_vtable client_channel_factory_vtable =
      client_channel_factory_create_subchannel,
      client_channel_factory_create_channel};
 
+static grpc_client_channel_factory client_channel_factory = {
+    &client_channel_factory_vtable};
+
 /* Create a secure client channel:
    Asynchronously: - resolve target
                    - connect to it (trying alternatives as presented)
@@ -138,33 +117,26 @@ grpc_channel *grpc_secure_channel_create(grpc_channel_credentials *creds,
     return grpc_lame_client_channel_create(
         target, GRPC_STATUS_INTERNAL, "Failed to create security connector.");
   }
-  // Create client channel factory.
-  client_channel_factory *f = gpr_malloc(sizeof(*f));
-  memset(f, 0, sizeof(*f));
-  f->base.vtable = &client_channel_factory_vtable;
-  gpr_ref_init(&f->refs, 1);
-  GRPC_SECURITY_CONNECTOR_REF(&security_connector->base,
-                              "grpc_secure_channel_create");
-  f->security_connector = security_connector;
   // Add channel args containing the client channel factory and security
   // connector.
-  grpc_arg new_args[2];
-  new_args[0] = grpc_client_channel_factory_create_channel_arg(&f->base);
-  new_args[1] = grpc_security_connector_to_arg(&security_connector->base);
-  grpc_channel_args *args_copy = grpc_channel_args_copy_and_add(
+  grpc_arg args_to_add[2];
+  args_to_add[0] =
+      grpc_client_channel_factory_create_channel_arg(&client_channel_factory);
+  args_to_add[1] = grpc_security_connector_to_arg(&security_connector->base);
+  grpc_channel_args *new_args = grpc_channel_args_copy_and_add(
       new_args_from_connector != NULL ? new_args_from_connector : args,
-      new_args, GPR_ARRAY_SIZE(new_args));
+      args_to_add, GPR_ARRAY_SIZE(args_to_add));
   if (new_args_from_connector != NULL) {
     grpc_channel_args_destroy(&exec_ctx, new_args_from_connector);
   }
   // Create channel.
   grpc_channel *channel = client_channel_factory_create_channel(
-      &exec_ctx, &f->base, target, GRPC_CLIENT_CHANNEL_TYPE_REGULAR, args_copy);
+      &exec_ctx, &client_channel_factory, target,
+      GRPC_CLIENT_CHANNEL_TYPE_REGULAR, new_args);
   // Clean up.
-  GRPC_SECURITY_CONNECTOR_UNREF(&exec_ctx, &f->security_connector->base,
+  GRPC_SECURITY_CONNECTOR_UNREF(&exec_ctx, &security_connector->base,
                                 "secure_client_channel_factory_create_channel");
-  grpc_channel_args_destroy(&exec_ctx, args_copy);
-  grpc_client_channel_factory_unref(&exec_ctx, &f->base);
+  grpc_channel_args_destroy(&exec_ctx, new_args);
   grpc_exec_ctx_finish(&exec_ctx);
   return channel; /* may be NULL */
 }
diff --git a/src/core/ext/transport/chttp2/server/chttp2_server.c b/src/core/ext/transport/chttp2/server/chttp2_server.c
index 86fe8d1ccd..56a1a0de9b 100644
--- a/src/core/ext/transport/chttp2/server/chttp2_server.c
+++ b/src/core/ext/transport/chttp2/server/chttp2_server.c
@@ -46,6 +46,7 @@
 #include "src/core/ext/transport/chttp2/transport/chttp2_transport.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/handshaker.h"
+#include "src/core/lib/channel/handshaker_registry.h"
 #include "src/core/lib/channel/http_server_filter.h"
 #include "src/core/lib/iomgr/endpoint.h"
 #include "src/core/lib/iomgr/resolve_address.h"
@@ -54,24 +55,6 @@
 #include "src/core/lib/surface/api_trace.h"
 #include "src/core/lib/surface/server.h"
 
-void grpc_chttp2_server_handshaker_factory_add_handshakers(
-    grpc_exec_ctx *exec_ctx,
-    grpc_chttp2_server_handshaker_factory *handshaker_factory,
-    grpc_handshake_manager *handshake_mgr) {
-  if (handshaker_factory != NULL) {
-    handshaker_factory->vtable->add_handshakers(exec_ctx, handshaker_factory,
-                                                handshake_mgr);
-  }
-}
-
-void grpc_chttp2_server_handshaker_factory_destroy(
-    grpc_exec_ctx *exec_ctx,
-    grpc_chttp2_server_handshaker_factory *handshaker_factory) {
-  if (handshaker_factory != NULL) {
-    handshaker_factory->vtable->destroy(exec_ctx, handshaker_factory);
-  }
-}
-
 typedef struct pending_handshake_manager_node {
   grpc_handshake_manager *handshake_mgr;
   struct pending_handshake_manager_node *next;
@@ -81,7 +64,6 @@ typedef struct {
   grpc_server *server;
   grpc_tcp_server *tcp_server;
   grpc_channel_args *args;
-  grpc_chttp2_server_handshaker_factory *handshaker_factory;
   gpr_mu mu;
   bool shutdown;
   grpc_closure tcp_server_shutdown_complete;
@@ -198,8 +180,8 @@ static void on_accept(grpc_exec_ctx *exec_ctx, void *arg, grpc_endpoint *tcp,
   connection_state->accepting_pollset = accepting_pollset;
   connection_state->acceptor = acceptor;
   connection_state->handshake_mgr = handshake_mgr;
-  grpc_chttp2_server_handshaker_factory_add_handshakers(
-      exec_ctx, state->handshaker_factory, connection_state->handshake_mgr);
+  grpc_handshakers_add(exec_ctx, HANDSHAKER_SERVER, state->args,
+                       connection_state->handshake_mgr);
   // TODO(roth): We should really get this timeout value from channel
   // args instead of hard-coding it.
   const gpr_timespec deadline = gpr_time_add(
@@ -233,8 +215,6 @@ static void tcp_server_shutdown_complete(grpc_exec_ctx *exec_ctx, void *arg,
   // Flush queued work before destroying handshaker factory, since that
   // may do a synchronous unref.
   grpc_exec_ctx_flush(exec_ctx);
-  grpc_chttp2_server_handshaker_factory_destroy(exec_ctx,
-                                                state->handshaker_factory);
   if (destroy_done != NULL) {
     destroy_done->cb(exec_ctx, destroy_done->cb_arg, GRPC_ERROR_REF(error));
     grpc_exec_ctx_flush(exec_ctx);
@@ -259,10 +239,10 @@ static void server_destroy_listener(grpc_exec_ctx *exec_ctx,
   grpc_tcp_server_unref(exec_ctx, tcp_server);
 }
 
-grpc_error *grpc_chttp2_server_add_port(
-    grpc_exec_ctx *exec_ctx, grpc_server *server, const char *addr,
-    grpc_channel_args *args,
-    grpc_chttp2_server_handshaker_factory *handshaker_factory, int *port_num) {
+grpc_error *grpc_chttp2_server_add_port(grpc_exec_ctx *exec_ctx,
+                                        grpc_server *server, const char *addr,
+                                        grpc_channel_args *args,
+                                        int *port_num) {
   grpc_resolved_addresses *resolved = NULL;
   grpc_tcp_server *tcp_server = NULL;
   size_t i;
@@ -293,7 +273,6 @@ grpc_error *grpc_chttp2_server_add_port(
   state->server = server;
   state->tcp_server = tcp_server;
   state->args = args;
-  state->handshaker_factory = handshaker_factory;
   state->shutdown = true;
   gpr_mu_init(&state->mu);
 
@@ -348,7 +327,6 @@ error:
     grpc_tcp_server_unref(exec_ctx, tcp_server);
   } else {
     grpc_channel_args_destroy(exec_ctx, args);
-    grpc_chttp2_server_handshaker_factory_destroy(exec_ctx, handshaker_factory);
     gpr_free(state);
   }
   *port_num = 0;
diff --git a/src/core/ext/transport/chttp2/server/chttp2_server.h b/src/core/ext/transport/chttp2/server/chttp2_server.h
index aa364b565d..2581ebaae9 100644
--- a/src/core/ext/transport/chttp2/server/chttp2_server.h
+++ b/src/core/ext/transport/chttp2/server/chttp2_server.h
@@ -36,43 +36,12 @@
 
 #include <grpc/impl/codegen/grpc_types.h>
 
-#include "src/core/lib/channel/handshaker.h"
 #include "src/core/lib/iomgr/exec_ctx.h"
 
-/// A server handshaker factory is used to create handshakers for server
-/// connections.
-typedef struct grpc_chttp2_server_handshaker_factory
-    grpc_chttp2_server_handshaker_factory;
-
-typedef struct {
-  void (*add_handshakers)(
-      grpc_exec_ctx *exec_ctx,
-      grpc_chttp2_server_handshaker_factory *handshaker_factory,
-      grpc_handshake_manager *handshake_mgr);
-  void (*destroy)(grpc_exec_ctx *exec_ctx,
-                  grpc_chttp2_server_handshaker_factory *handshaker_factory);
-} grpc_chttp2_server_handshaker_factory_vtable;
-
-struct grpc_chttp2_server_handshaker_factory {
-  const grpc_chttp2_server_handshaker_factory_vtable *vtable;
-};
-
-void grpc_chttp2_server_handshaker_factory_add_handshakers(
-    grpc_exec_ctx *exec_ctx,
-    grpc_chttp2_server_handshaker_factory *handshaker_factory,
-    grpc_handshake_manager *handshake_mgr);
-
-void grpc_chttp2_server_handshaker_factory_destroy(
-    grpc_exec_ctx *exec_ctx,
-    grpc_chttp2_server_handshaker_factory *handshaker_factory);
-
 /// Adds a port to \a server.  Sets \a port_num to the port number.
-/// If \a handshaker_factory is not NULL, it will be used to create
-/// handshakers for the port.
-/// Takes ownership of \a args and \a handshaker_factory.
-grpc_error *grpc_chttp2_server_add_port(
-    grpc_exec_ctx *exec_ctx, grpc_server *server, const char *addr,
-    grpc_channel_args *args,
-    grpc_chttp2_server_handshaker_factory *handshaker_factory, int *port_num);
+/// Takes ownership of \a args.
+grpc_error *grpc_chttp2_server_add_port(grpc_exec_ctx *exec_ctx,
+                                        grpc_server *server, const char *addr,
+                                        grpc_channel_args *args, int *port_num);
 
 #endif /* GRPC_CORE_EXT_TRANSPORT_CHTTP2_SERVER_CHTTP2_SERVER_H */
diff --git a/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c b/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c
index 77ed26a54a..c219a7d85f 100644
--- a/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c
+++ b/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c
@@ -47,8 +47,7 @@ int grpc_server_add_insecure_http2_port(grpc_server *server, const char *addr) {
                  (server, addr));
   grpc_error *err = grpc_chttp2_server_add_port(
       &exec_ctx, server, addr,
-      grpc_channel_args_copy(grpc_server_get_channel_args(server)),
-      NULL /* handshaker_factory */, &port_num);
+      grpc_channel_args_copy(grpc_server_get_channel_args(server)), &port_num);
   if (err != GRPC_ERROR_NONE) {
     const char *msg = grpc_error_string(err);
     gpr_log(GPR_ERROR, "%s", msg);
diff --git a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
index f909a760d0..cb2b3f5502 100644
--- a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
+++ b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
@@ -49,34 +49,6 @@
 #include "src/core/lib/surface/api_trace.h"
 #include "src/core/lib/surface/server.h"
 
-typedef struct {
-  grpc_chttp2_server_handshaker_factory base;
-  grpc_server_security_connector *security_connector;
-} server_security_handshaker_factory;
-
-static void server_security_handshaker_factory_add_handshakers(
-    grpc_exec_ctx *exec_ctx, grpc_chttp2_server_handshaker_factory *hf,
-    grpc_handshake_manager *handshake_mgr) {
-  server_security_handshaker_factory *handshaker_factory =
-      (server_security_handshaker_factory *)hf;
-  grpc_server_security_connector_add_handshakers(
-      exec_ctx, handshaker_factory->security_connector, handshake_mgr);
-}
-
-static void server_security_handshaker_factory_destroy(
-    grpc_exec_ctx *exec_ctx, grpc_chttp2_server_handshaker_factory *hf) {
-  server_security_handshaker_factory *handshaker_factory =
-      (server_security_handshaker_factory *)hf;
-  GRPC_SECURITY_CONNECTOR_UNREF(
-      exec_ctx, &handshaker_factory->security_connector->base, "server");
-  gpr_free(hf);
-}
-
-static const grpc_chttp2_server_handshaker_factory_vtable
-    server_security_handshaker_factory_vtable = {
-        server_security_handshaker_factory_add_handshakers,
-        server_security_handshaker_factory_destroy};
-
 int grpc_server_add_secure_http2_port(grpc_server *server, const char *addr,
                                       grpc_server_credentials *creds) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
@@ -105,20 +77,19 @@ int grpc_server_add_secure_http2_port(grpc_server *server, const char *addr,
     gpr_free(msg);
     goto done;
   }
-  // Create handshaker factory.
-  server_security_handshaker_factory *handshaker_factory =
-      gpr_malloc(sizeof(*handshaker_factory));
-  memset(handshaker_factory, 0, sizeof(*handshaker_factory));
-  handshaker_factory->base.vtable = &server_security_handshaker_factory_vtable;
-  handshaker_factory->security_connector = sc;
   // Create channel args.
-  grpc_arg channel_arg = grpc_server_credentials_to_arg(creds);
-  grpc_channel_args *args = grpc_channel_args_copy_and_add(
-      grpc_server_get_channel_args(server), &channel_arg, 1);
+  grpc_arg args_to_add[2];
+  args_to_add[0] = grpc_server_credentials_to_arg(creds);
+  args_to_add[1] = grpc_security_connector_to_arg(&sc->base);
+  grpc_channel_args *args =
+      grpc_channel_args_copy_and_add(grpc_server_get_channel_args(server),
+                                     args_to_add, GPR_ARRAY_SIZE(args_to_add));
   // Add server port.
-  err = grpc_chttp2_server_add_port(&exec_ctx, server, addr, args,
-                                    &handshaker_factory->base, &port_num);
+  err = grpc_chttp2_server_add_port(&exec_ctx, server, addr, args, &port_num);
 done:
+  if (sc != NULL) {
+    GRPC_SECURITY_CONNECTOR_UNREF(&exec_ctx, &sc->base, "server");
+  }
   grpc_exec_ctx_finish(&exec_ctx);
   if (err != GRPC_ERROR_NONE) {
     const char *msg = grpc_error_string(err);
diff --git a/src/core/lib/channel/handshaker_factory.c b/src/core/lib/channel/handshaker_factory.c
new file mode 100644
index 0000000000..3c30a4e1d2
--- /dev/null
+++ b/src/core/lib/channel/handshaker_factory.c
@@ -0,0 +1,54 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "src/core/lib/channel/handshaker_factory.h"
+
+#include <grpc/support/log.h>
+
+void grpc_handshaker_factory_add_handshakers(
+    grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *handshaker_factory,
+    const grpc_channel_args *args, grpc_handshake_manager *handshake_mgr) {
+  if (handshaker_factory != NULL) {
+    GPR_ASSERT(handshaker_factory->vtable != NULL);
+    handshaker_factory->vtable->add_handshakers(exec_ctx, handshaker_factory,
+                                                args, handshake_mgr);
+  }
+}
+
+void grpc_handshaker_factory_destroy(
+    grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *handshaker_factory) {
+  if (handshaker_factory != NULL) {
+    GPR_ASSERT(handshaker_factory->vtable != NULL);
+    handshaker_factory->vtable->destroy(exec_ctx, handshaker_factory);
+  }
+}
diff --git a/src/core/lib/channel/handshaker_factory.h b/src/core/lib/channel/handshaker_factory.h
new file mode 100644
index 0000000000..1984546104
--- /dev/null
+++ b/src/core/lib/channel/handshaker_factory.h
@@ -0,0 +1,66 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPC_CORE_LIB_CHANNEL_HANDSHAKER_FACTORY_H
+#define GRPC_CORE_LIB_CHANNEL_HANDSHAKER_FACTORY_H
+
+#include <grpc/impl/codegen/grpc_types.h>
+
+#include "src/core/lib/channel/handshaker.h"
+#include "src/core/lib/iomgr/exec_ctx.h"
+
+// A handshaker factory is used to create handshakers.
+
+typedef struct grpc_handshaker_factory grpc_handshaker_factory;
+
+typedef struct {
+  void (*add_handshakers)(grpc_exec_ctx *exec_ctx,
+                          grpc_handshaker_factory *handshaker_factory,
+                          const grpc_channel_args *args,
+                          grpc_handshake_manager *handshake_mgr);
+  void (*destroy)(grpc_exec_ctx *exec_ctx,
+                  grpc_handshaker_factory *handshaker_factory);
+} grpc_handshaker_factory_vtable;
+
+struct grpc_handshaker_factory {
+  const grpc_handshaker_factory_vtable *vtable;
+};
+
+void grpc_handshaker_factory_add_handshakers(
+    grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *handshaker_factory,
+    const grpc_channel_args *args, grpc_handshake_manager *handshake_mgr);
+
+void grpc_handshaker_factory_destroy(
+    grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *handshaker_factory);
+
+#endif /* GRPC_CORE_LIB_CHANNEL_HANDSHAKER_FACTORY_H */
diff --git a/src/core/lib/channel/handshaker_registry.c b/src/core/lib/channel/handshaker_registry.c
new file mode 100644
index 0000000000..2e5f04064c
--- /dev/null
+++ b/src/core/lib/channel/handshaker_registry.c
@@ -0,0 +1,113 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "src/core/lib/channel/handshaker_registry.h"
+
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+
+//
+// grpc_handshaker_factory_list
+//
+
+typedef struct {
+  grpc_handshaker_factory** list;
+  size_t num_factories;
+} grpc_handshaker_factory_list;
+
+static void grpc_handshaker_factory_list_register(
+    grpc_handshaker_factory_list* list, bool at_start,
+    grpc_handshaker_factory* factory) {
+  list->list = gpr_realloc(
+      list->list, (list->num_factories + 1) * sizeof(grpc_handshaker_factory*));
+  if (at_start) {
+    memmove(list->list + 1, list->list,
+            sizeof(grpc_handshaker_factory*) * list->num_factories);
+    list->list[0] = factory;
+  } else {
+    list->list[list->num_factories] = factory;
+  }
+  ++list->num_factories;
+}
+
+static void grpc_handshaker_factory_list_add_handshakers(
+    grpc_exec_ctx* exec_ctx, grpc_handshaker_factory_list* list,
+    const grpc_channel_args* args, grpc_handshake_manager* handshake_mgr) {
+  for (size_t i = 0; i < list->num_factories; ++i) {
+    grpc_handshaker_factory_add_handshakers(exec_ctx, list->list[i], args,
+                                            handshake_mgr);
+  }
+}
+
+static void grpc_handshaker_factory_list_destroy(
+    grpc_exec_ctx* exec_ctx, grpc_handshaker_factory_list* list) {
+  for (size_t i = 0; i < list->num_factories; ++i) {
+    grpc_handshaker_factory_destroy(exec_ctx, list->list[i]);
+  }
+  gpr_free(list->list);
+}
+
+//
+// plugin
+//
+
+static grpc_handshaker_factory_list
+    g_handshaker_factory_lists[NUM_HANDSHAKER_TYPES];
+
+void grpc_handshaker_factory_registry_init() {
+  memset(g_handshaker_factory_lists, 0, sizeof(g_handshaker_factory_lists));
+}
+
+void grpc_handshaker_factory_registry_shutdown(grpc_exec_ctx* exec_ctx) {
+  for (size_t i = 0; i < NUM_HANDSHAKER_TYPES; ++i) {
+    grpc_handshaker_factory_list_destroy(exec_ctx,
+                                         &g_handshaker_factory_lists[i]);
+  }
+}
+
+void grpc_handshaker_factory_register(bool at_start,
+                                      grpc_handshaker_type handshaker_type,
+                                      grpc_handshaker_factory* factory) {
+  grpc_handshaker_factory_list_register(
+      &g_handshaker_factory_lists[handshaker_type], at_start, factory);
+}
+
+void grpc_handshakers_add(grpc_exec_ctx* exec_ctx,
+                          grpc_handshaker_type handshaker_type,
+                          const grpc_channel_args* args,
+                          grpc_handshake_manager* handshake_mgr) {
+  grpc_handshaker_factory_list_add_handshakers(
+      exec_ctx, &g_handshaker_factory_lists[handshaker_type], args,
+      handshake_mgr);
+}
diff --git a/src/core/lib/channel/handshaker_registry.h b/src/core/lib/channel/handshaker_registry.h
new file mode 100644
index 0000000000..53c1b173af
--- /dev/null
+++ b/src/core/lib/channel/handshaker_registry.h
@@ -0,0 +1,63 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPC_CORE_LIB_CHANNEL_HANDSHAKER_REGISTRY_H
+#define GRPC_CORE_LIB_CHANNEL_HANDSHAKER_REGISTRY_H
+
+#include <grpc/impl/codegen/grpc_types.h>
+
+#include "src/core/lib/channel/handshaker_factory.h"
+#include "src/core/lib/iomgr/exec_ctx.h"
+
+typedef enum {
+  HANDSHAKER_CLIENT = 0,
+  HANDSHAKER_SERVER,
+  NUM_HANDSHAKER_TYPES,  // Must be last.
+} grpc_handshaker_type;
+
+void grpc_handshaker_factory_registry_init();
+void grpc_handshaker_factory_registry_shutdown(grpc_exec_ctx* exec_ctx);
+
+/// Registers a new handshaker factory.  Takes ownership.
+/// If \a at_start is true, the new handshaker will be at the beginning of
+/// the list.  Otherwise, it will be added to the end.
+void grpc_handshaker_factory_register(bool at_start,
+                                      grpc_handshaker_type handshaker_type,
+                                      grpc_handshaker_factory* factory);
+
+void grpc_handshakers_add(grpc_exec_ctx* exec_ctx,
+                          grpc_handshaker_type handshaker_type,
+                          const grpc_channel_args* args,
+                          grpc_handshake_manager* handshake_mgr);
+
+#endif /* GRPC_CORE_LIB_CHANNEL_HANDSHAKER_REGISTRY_H */
diff --git a/src/core/lib/channel/message_size_filter.c b/src/core/lib/channel/message_size_filter.c
index 3578f20827..d9862c5252 100644
--- a/src/core/lib/channel/message_size_filter.c
+++ b/src/core/lib/channel/message_size_filter.c
@@ -147,6 +147,7 @@ static void start_transport_stream_op(grpc_exec_ctx* exec_ctx,
                                          GRPC_ERROR_INT_GRPC_STATUS,
                                          GRPC_STATUS_INVALID_ARGUMENT));
     gpr_free(message_string);
+    return;
   }
   // Inject callback for receiving a message.
   if (op->recv_message_ready != NULL) {
diff --git a/src/core/lib/security/transport/security_handshaker.c b/src/core/lib/security/transport/security_handshaker.c
index 6891debfd3..37d57d759b 100644
--- a/src/core/lib/security/transport/security_handshaker.c
+++ b/src/core/lib/security/transport/security_handshaker.c
@@ -42,6 +42,7 @@
 
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/handshaker.h"
+#include "src/core/lib/channel/handshaker_registry.h"
 #include "src/core/lib/security/context/security_context.h"
 #include "src/core/lib/security/transport/secure_endpoint.h"
 #include "src/core/lib/security/transport/tsi_error.h"
@@ -438,6 +439,45 @@ static grpc_handshaker *fail_handshaker_create() {
 }
 
 //
+// handshaker factories
+//
+
+static void client_handshaker_factory_add_handshakers(
+    grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *handshaker_factory,
+    const grpc_channel_args *args, grpc_handshake_manager *handshake_mgr) {
+  grpc_channel_security_connector *security_connector =
+      (grpc_channel_security_connector *)grpc_find_security_connector_in_args(
+          args);
+  grpc_channel_security_connector_add_handshakers(exec_ctx, security_connector,
+                                                  handshake_mgr);
+}
+
+static void server_handshaker_factory_add_handshakers(
+    grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *hf,
+    const grpc_channel_args *args, grpc_handshake_manager *handshake_mgr) {
+  grpc_server_security_connector *security_connector =
+      (grpc_server_security_connector *)grpc_find_security_connector_in_args(
+          args);
+  grpc_server_security_connector_add_handshakers(exec_ctx, security_connector,
+                                                 handshake_mgr);
+}
+
+static void handshaker_factory_destroy(
+    grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *handshaker_factory) {}
+
+static const grpc_handshaker_factory_vtable client_handshaker_factory_vtable = {
+    client_handshaker_factory_add_handshakers, handshaker_factory_destroy};
+
+static grpc_handshaker_factory client_handshaker_factory = {
+    &client_handshaker_factory_vtable};
+
+static const grpc_handshaker_factory_vtable server_handshaker_factory_vtable = {
+    server_handshaker_factory_add_handshakers, handshaker_factory_destroy};
+
+static grpc_handshaker_factory server_handshaker_factory = {
+    &server_handshaker_factory_vtable};
+
+//
 // exported functions
 //
 
@@ -452,3 +492,10 @@ grpc_handshaker *grpc_security_handshaker_create(
     return security_handshaker_create(exec_ctx, handshaker, connector);
   }
 }
+
+void grpc_security_register_handshaker_factories() {
+  grpc_handshaker_factory_register(false /* at_start */, HANDSHAKER_CLIENT,
+                                   &client_handshaker_factory);
+  grpc_handshaker_factory_register(false /* at_start */, HANDSHAKER_SERVER,
+                                   &server_handshaker_factory);
+}
diff --git a/src/core/lib/security/transport/security_handshaker.h b/src/core/lib/security/transport/security_handshaker.h
index 5ddbf4b451..0b9eda178f 100644
--- a/src/core/lib/security/transport/security_handshaker.h
+++ b/src/core/lib/security/transport/security_handshaker.h
@@ -43,4 +43,7 @@ grpc_handshaker *grpc_security_handshaker_create(
     grpc_exec_ctx *exec_ctx, tsi_handshaker *handshaker,
     grpc_security_connector *connector);
 
+/// Registers security handshaker factories.
+void grpc_security_register_handshaker_factories();
+
 #endif /* GRPC_CORE_LIB_SECURITY_TRANSPORT_SECURITY_HANDSHAKER_H */
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index 009e36fd87..0d63ef051a 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -1053,12 +1053,7 @@ static void post_batch_completion(grpc_exec_ctx *exec_ctx,
   }
 }
 
-static void finish_batch_step(grpc_exec_ctx *exec_ctx, batch_control *bctl,
-                              const char *but_why) {
-  gpr_log(GPR_DEBUG,
-          "finish_batch_step: call=%p bctl=%p why='%s' still_needed=%" PRIdPTR,
-          bctl->call, bctl, but_why,
-          gpr_atm_no_barrier_load(&bctl->steps_to_complete.count));
+static void finish_batch_step(grpc_exec_ctx *exec_ctx, batch_control *bctl) {
   if (gpr_unref(&bctl->steps_to_complete)) {
     post_batch_completion(exec_ctx, bctl);
   }
@@ -1074,7 +1069,7 @@ static void continue_receiving_slices(grpc_exec_ctx *exec_ctx,
       call->receiving_message = 0;
       grpc_byte_stream_destroy(exec_ctx, call->receiving_stream);
       call->receiving_stream = NULL;
-      finish_batch_step(exec_ctx, bctl, "continue_receiving_slices");
+      finish_batch_step(exec_ctx, bctl);
       return;
     }
     if (grpc_byte_stream_next(exec_ctx, call->receiving_stream,
@@ -1105,7 +1100,7 @@ static void receiving_slice_ready(grpc_exec_ctx *exec_ctx, void *bctlp,
     call->receiving_stream = NULL;
     grpc_byte_buffer_destroy(*call->receiving_buffer);
     *call->receiving_buffer = NULL;
-    finish_batch_step(exec_ctx, bctl, "receiving_slice_ready with error");
+    finish_batch_step(exec_ctx, bctl);
   }
 }
 
@@ -1115,7 +1110,7 @@ static void process_data_after_md(grpc_exec_ctx *exec_ctx,
   if (call->receiving_stream == NULL) {
     *call->receiving_buffer = NULL;
     call->receiving_message = 0;
-    finish_batch_step(exec_ctx, bctl, "no message");
+    finish_batch_step(exec_ctx, bctl);
   } else {
     call->test_only_last_message_flags = call->receiving_stream->flags;
     if ((call->receiving_stream->flags & GRPC_WRITE_INTERNAL_COMPRESS) &&
@@ -1141,11 +1136,12 @@ static void receiving_stream_ready(grpc_exec_ctx *exec_ctx, void *bctlp,
   }
   if (call->has_initial_md_been_received || error != GRPC_ERROR_NONE ||
       call->receiving_stream == NULL) {
+    gpr_mu_unlock(&bctl->call->mu);
     process_data_after_md(exec_ctx, bctlp);
   } else {
     call->saved_receiving_stream_ready_bctlp = bctlp;
+    gpr_mu_unlock(&bctl->call->mu);
   }
-  gpr_mu_unlock(&bctl->call->mu);
 }
 
 static void validate_filtered_metadata(grpc_exec_ctx *exec_ctx,
@@ -1243,7 +1239,7 @@ static void receiving_initial_metadata_ready(grpc_exec_ctx *exec_ctx,
 
   gpr_mu_unlock(&call->mu);
 
-  finish_batch_step(exec_ctx, bctl, "receiving_initial_metadata_ready");
+  finish_batch_step(exec_ctx, bctl);
 }
 
 static void finish_batch(grpc_exec_ctx *exec_ctx, void *bctlp,
@@ -1251,7 +1247,7 @@ static void finish_batch(grpc_exec_ctx *exec_ctx, void *bctlp,
   batch_control *bctl = bctlp;
 
   add_batch_error(exec_ctx, bctl, GRPC_ERROR_REF(error));
-  finish_batch_step(exec_ctx, bctl, "finish_batch");
+  finish_batch_step(exec_ctx, bctl);
 }
 
 static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/surface/init.c b/src/core/lib/surface/init.c
index 91b8f2b068..cfa1882775 100644
--- a/src/core/lib/surface/init.c
+++ b/src/core/lib/surface/init.c
@@ -44,6 +44,7 @@
 #include "src/core/lib/channel/compress_filter.h"
 #include "src/core/lib/channel/connected_channel.h"
 #include "src/core/lib/channel/deadline_filter.h"
+#include "src/core/lib/channel/handshaker_registry.h"
 #include "src/core/lib/channel/http_client_filter.h"
 #include "src/core/lib/channel/http_server_filter.h"
 #include "src/core/lib/channel/message_size_filter.h"
@@ -206,6 +207,8 @@ void grpc_init(void) {
     grpc_executor_init();
     gpr_timers_global_init();
     grpc_cq_global_init();
+    grpc_handshaker_factory_registry_init();
+    grpc_security_init();
     for (i = 0; i < g_number_of_plugins; i++) {
       if (g_all_of_the_plugins[i].init != NULL) {
         g_all_of_the_plugins[i].init();
@@ -240,6 +243,7 @@ void grpc_shutdown(void) {
       }
     }
     grpc_mdctx_global_shutdown(&exec_ctx);
+    grpc_handshaker_factory_registry_shutdown(&exec_ctx);
     grpc_slice_intern_shutdown();
   }
   gpr_mu_unlock(&g_init_mu);
diff --git a/src/core/lib/surface/init.h b/src/core/lib/surface/init.h
index b1bf57c10d..3d1c528be0 100644
--- a/src/core/lib/surface/init.h
+++ b/src/core/lib/surface/init.h
@@ -36,6 +36,7 @@
 
 void grpc_register_security_filters(void);
 void grpc_security_pre_init(void);
+void grpc_security_init(void);
 int grpc_is_initialized(void);
 
 #endif /* GRPC_CORE_LIB_SURFACE_INIT_H */
diff --git a/src/core/lib/surface/init_secure.c b/src/core/lib/surface/init_secure.c
index 520a8aa84f..a44407d3bb 100644
--- a/src/core/lib/surface/init_secure.c
+++ b/src/core/lib/surface/init_secure.c
@@ -41,6 +41,7 @@
 #include "src/core/lib/security/transport/auth_filters.h"
 #include "src/core/lib/security/transport/secure_endpoint.h"
 #include "src/core/lib/security/transport/security_connector.h"
+#include "src/core/lib/security/transport/security_handshaker.h"
 #include "src/core/lib/surface/channel_init.h"
 #include "src/core/lib/tsi/transport_security_interface.h"
 
@@ -87,3 +88,5 @@ void grpc_register_security_filters(void) {
   grpc_channel_init_register_stage(GRPC_SERVER_CHANNEL, INT_MAX,
                                    maybe_prepend_server_auth_filter, NULL);
 }
+
+void grpc_security_init() { grpc_security_register_handshaker_factories(); }
diff --git a/src/core/lib/surface/init_unsecure.c b/src/core/lib/surface/init_unsecure.c
index f952739e0a..dbc9223ae0 100644
--- a/src/core/lib/surface/init_unsecure.c
+++ b/src/core/lib/surface/init_unsecure.c
@@ -36,3 +36,5 @@
 void grpc_security_pre_init(void) {}
 
 void grpc_register_security_filters(void) {}
+
+void grpc_security_init(void) {}
diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index dfb64f8744..5d1a9ee327 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -82,6 +82,8 @@ CORE_SOURCE_FILES = [
   'src/core/lib/channel/connected_channel.c',
   'src/core/lib/channel/deadline_filter.c',
   'src/core/lib/channel/handshaker.c',
+  'src/core/lib/channel/handshaker_factory.c',
+  'src/core/lib/channel/handshaker_registry.c',
   'src/core/lib/channel/http_client_filter.c',
   'src/core/lib/channel/http_server_filter.c',
   'src/core/lib/channel/message_size_filter.c',
diff --git a/test/core/end2end/tests/resource_quota_server.c b/test/core/end2end/tests/resource_quota_server.c
index a3c6c6c2bd..f65d60327c 100644
--- a/test/core/end2end/tests/resource_quota_server.c
+++ b/test/core/end2end/tests/resource_quota_server.c
@@ -351,10 +351,6 @@ void resource_quota_server(grpc_end2end_test_config config) {
    * the client has received it. This means that we should see strictly more
    * failures on the client than on the server. */
   GPR_ASSERT(cancelled_calls_on_client >= cancelled_calls_on_server);
-  /* However, we shouldn't see radically more... 0.9 is a guessed bound on what
-   * we'd want that ratio to be... to at least trigger some investigation should
-   * that ratio become much higher. */
-  GPR_ASSERT(cancelled_calls_on_server >= 0.9 * cancelled_calls_on_client);
 
   grpc_byte_buffer_destroy(request_payload);
   grpc_slice_unref(request_payload_slice);
diff --git a/tools/doxygen/Doxyfile.core.internal b/tools/doxygen/Doxyfile.core.internal
index f9343a2b73..f1dd43c33b 100644
--- a/tools/doxygen/Doxyfile.core.internal
+++ b/tools/doxygen/Doxyfile.core.internal
@@ -797,6 +797,8 @@ src/core/lib/channel/connected_channel.h \
 src/core/lib/channel/context.h \
 src/core/lib/channel/deadline_filter.h \
 src/core/lib/channel/handshaker.h \
+src/core/lib/channel/handshaker_factory.h \
+src/core/lib/channel/handshaker_registry.h \
 src/core/lib/channel/http_client_filter.h \
 src/core/lib/channel/http_server_filter.h \
 src/core/lib/channel/message_size_filter.h \
@@ -979,6 +981,8 @@ src/core/lib/channel/compress_filter.c \
 src/core/lib/channel/connected_channel.c \
 src/core/lib/channel/deadline_filter.c \
 src/core/lib/channel/handshaker.c \
+src/core/lib/channel/handshaker_factory.c \
+src/core/lib/channel/handshaker_registry.c \
 src/core/lib/channel/http_client_filter.c \
 src/core/lib/channel/http_server_filter.c \
 src/core/lib/channel/message_size_filter.c \
diff --git a/tools/run_tests/README.md b/tools/run_tests/README.md
index dd727f4309..e709ddd2c0 100644
--- a/tools/run_tests/README.md
+++ b/tools/run_tests/README.md
@@ -22,6 +22,10 @@ The script is also capable of running interop tests for grpc-java and grpc-go, u
 ######Example
 `tools/run_tests/run_interop_tests.py -l csharp -s c++ --use_docker` (run interop tests with C# client and C++ server)
 
+Note: if you see an error like `no space left on device` when running the
+interop tests using Docker, make sure that Docker is building the image files in
+a location with sufficient disk space.
+
 #Performance benchmarks (run_performance_tests.py)
 
 Runs predefined benchmark scenarios for given languages. Besides the simple configuration of running all the scenarios locally,
diff --git a/tools/run_tests/generated/sources_and_headers.json b/tools/run_tests/generated/sources_and_headers.json
index 0550902184..54029b0f76 100644
--- a/tools/run_tests/generated/sources_and_headers.json
+++ b/tools/run_tests/generated/sources_and_headers.json
@@ -6681,6 +6681,8 @@
       "src/core/lib/channel/context.h", 
       "src/core/lib/channel/deadline_filter.h", 
       "src/core/lib/channel/handshaker.h", 
+      "src/core/lib/channel/handshaker_factory.h", 
+      "src/core/lib/channel/handshaker_registry.h", 
       "src/core/lib/channel/http_client_filter.h", 
       "src/core/lib/channel/http_server_filter.h", 
       "src/core/lib/channel/message_size_filter.h", 
@@ -6804,6 +6806,10 @@
       "src/core/lib/channel/deadline_filter.h", 
       "src/core/lib/channel/handshaker.c", 
       "src/core/lib/channel/handshaker.h", 
+      "src/core/lib/channel/handshaker_factory.c", 
+      "src/core/lib/channel/handshaker_factory.h", 
+      "src/core/lib/channel/handshaker_registry.c", 
+      "src/core/lib/channel/handshaker_registry.h", 
       "src/core/lib/channel/http_client_filter.c", 
       "src/core/lib/channel/http_client_filter.h", 
       "src/core/lib/channel/http_server_filter.c", 
diff --git a/vsprojects/README.md b/vsprojects/README.md
index 7af69c2726..afd6430bfe 100644
--- a/vsprojects/README.md
+++ b/vsprojects/README.md
@@ -2,7 +2,7 @@ This directory contains MS Visual Studio project & solution files.
 
 #Supported Visual Studio versions
 
-Currently supported versions are Visual Studio 2013 (our primary focus) and 2010.
+Currently supported versions are Visual Studio 2013 (our primary focus).
 
 #Building
 We are using [NuGet](http://www.nuget.org) to pull zlib and openssl dependencies.
diff --git a/vsprojects/build_vs2010.bat b/vsprojects/build_vs2010.bat
deleted file mode 100644
index d951295369..0000000000
--- a/vsprojects/build_vs2010.bat
+++ /dev/null
@@ -1,39 +0,0 @@
-@rem Copyright 2016, Google Inc.
-@rem All rights reserved.
-@rem
-@rem Redistribution and use in source and binary forms, with or without
-@rem modification, are permitted provided that the following conditions are
-@rem met:
-@rem
-@rem     * Redistributions of source code must retain the above copyright
-@rem notice, this list of conditions and the following disclaimer.
-@rem     * Redistributions in binary form must reproduce the above
-@rem copyright notice, this list of conditions and the following disclaimer
-@rem in the documentation and/or other materials provided with the
-@rem distribution.
-@rem     * Neither the name of Google Inc. nor the names of its
-@rem contributors may be used to endorse or promote products derived from
-@rem this software without specific prior written permission.
-@rem
-@rem THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-@rem "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-@rem LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-@rem A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-@rem OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-@rem SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-@rem LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-@rem DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-@rem THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-@rem (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-@rem OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-@rem Convenience wrapper that runs specified gRPC target using msbuild
-@rem Usage: build_vs2010.bat TARGET_NAME
-
-setlocal
-@rem Set VS variables (uses Visual Studio 2010)
-@call "%VS100COMNTOOLS%\..\..\vc\vcvarsall.bat" x86
-
-msbuild %*
-exit /b %ERRORLEVEL%
-endlocal
diff --git a/vsprojects/coapp/zlib/README.md b/vsprojects/coapp/zlib/README.md
index d62e9030ed..e9a89c030e 100644
--- a/vsprojects/coapp/zlib/README.md
+++ b/vsprojects/coapp/zlib/README.md
@@ -10,7 +10,7 @@ Multiple versions of VS installed to be able to build all the targets:
 * Visual Studio 2013
 * Visual Studio 2010 (you might need SP1 to prevent LNK1123 error)
 
-CoApp toolkit: http://downloads.coapp.org/files/CoApp.Tools.Powershell.msi
+CoApp toolkit: http://coapp.org/files/CoApp.Tools.Powershell.msi
 
 More details on installation: http://coapp.org/tutorials/installation.html
 
@@ -33,4 +33,4 @@ This will create three NuGet packages:
 * the symbols package (debug symbols)
 
 Later, you can push the package to NuGet.org repo.
-Attention: before pusing the resulting nuget package to public nuget repo, you have to be 100% sure it works correctly - there’s no way how to delete or update an already existing package.
\ No newline at end of file
+Attention: before pusing the resulting nuget package to public nuget repo, you have to be 100% sure it works correctly - there’s no way how to delete or update an already existing package.
diff --git a/vsprojects/vcxproj/grpc/grpc.vcxproj b/vsprojects/vcxproj/grpc/grpc.vcxproj
index b408a0c634..b184107208 100644
--- a/vsprojects/vcxproj/grpc/grpc.vcxproj
+++ b/vsprojects/vcxproj/grpc/grpc.vcxproj
@@ -306,6 +306,8 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\context.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\deadline_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\http_server_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\message_size_filter.h" />
@@ -498,6 +500,10 @@
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.c">
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\http_server_filter.c">
diff --git a/vsprojects/vcxproj/grpc/grpc.vcxproj.filters b/vsprojects/vcxproj/grpc/grpc.vcxproj.filters
index f64d4aaa54..96c9364263 100644
--- a/vsprojects/vcxproj/grpc/grpc.vcxproj.filters
+++ b/vsprojects/vcxproj/grpc/grpc.vcxproj.filters
@@ -25,6 +25,12 @@
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.c">
       <Filter>src\core\lib\channel</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.c">
+      <Filter>src\core\lib\channel</Filter>
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.c">
+      <Filter>src\core\lib\channel</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.c">
       <Filter>src\core\lib\channel</Filter>
     </ClCompile>
@@ -767,6 +773,12 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.h">
       <Filter>src\core\lib\channel</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.h">
+      <Filter>src\core\lib\channel</Filter>
+    </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.h">
+      <Filter>src\core\lib\channel</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.h">
       <Filter>src\core\lib\channel</Filter>
     </ClInclude>
diff --git a/vsprojects/vcxproj/grpc_test_util/grpc_test_util.vcxproj b/vsprojects/vcxproj/grpc_test_util/grpc_test_util.vcxproj
index 6c7af6ca01..72536a6216 100644
--- a/vsprojects/vcxproj/grpc_test_util/grpc_test_util.vcxproj
+++ b/vsprojects/vcxproj/grpc_test_util/grpc_test_util.vcxproj
@@ -199,6 +199,8 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\context.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\deadline_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\http_server_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\message_size_filter.h" />
@@ -349,6 +351,10 @@
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.c">
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\http_server_filter.c">
diff --git a/vsprojects/vcxproj/grpc_test_util/grpc_test_util.vcxproj.filters b/vsprojects/vcxproj/grpc_test_util/grpc_test_util.vcxproj.filters
index eea0fe8009..7deb60e8bc 100644
--- a/vsprojects/vcxproj/grpc_test_util/grpc_test_util.vcxproj.filters
+++ b/vsprojects/vcxproj/grpc_test_util/grpc_test_util.vcxproj.filters
@@ -82,6 +82,12 @@
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.c">
       <Filter>src\core\lib\channel</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.c">
+      <Filter>src\core\lib\channel</Filter>
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.c">
+      <Filter>src\core\lib\channel</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.c">
       <Filter>src\core\lib\channel</Filter>
     </ClCompile>
@@ -560,6 +566,12 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.h">
       <Filter>src\core\lib\channel</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.h">
+      <Filter>src\core\lib\channel</Filter>
+    </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.h">
+      <Filter>src\core\lib\channel</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.h">
       <Filter>src\core\lib\channel</Filter>
     </ClInclude>
diff --git a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj
index ea491dc69a..72238af255 100644
--- a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj
+++ b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj
@@ -296,6 +296,8 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\context.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\deadline_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\http_server_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\message_size_filter.h" />
@@ -466,6 +468,10 @@
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.c">
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\http_server_filter.c">
diff --git a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
index 1bff26e9b8..405c7ea991 100644
--- a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
+++ b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
@@ -28,6 +28,12 @@
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.c">
       <Filter>src\core\lib\channel</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.c">
+      <Filter>src\core\lib\channel</Filter>
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.c">
+      <Filter>src\core\lib\channel</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.c">
       <Filter>src\core\lib\channel</Filter>
     </ClCompile>
@@ -680,6 +686,12 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker.h">
       <Filter>src\core\lib\channel</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_factory.h">
+      <Filter>src\core\lib\channel</Filter>
+    </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\handshaker_registry.h">
+      <Filter>src\core\lib\channel</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\lib\channel\http_client_filter.h">
       <Filter>src\core\lib\channel</Filter>
     </ClInclude>