--- /dev/null
+//
+// Copyright 2017 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 <grpc/support/port_platform.h>
+
+#include "src/core/ext/filters/workarounds/workaround_cronet_compression_filter.h"
+
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+
+#include "src/core/ext/filters/workarounds/workaround_utils.h"
+#include "src/core/lib/channel/channel_stack_builder.h"
+#include "src/core/lib/surface/channel_init.h"
+#include "src/core/lib/transport/metadata.h"
+
+namespace {
+struct call_data {
+ // Receive closures are chained: we inject this closure as the
+ // recv_initial_metadata_ready up-call on transport_stream_op, and remember to
+ // call our next_recv_initial_metadata_ready member after handling it.
+ grpc_closure recv_initial_metadata_ready;
+ // Used by recv_initial_metadata_ready.
+ grpc_metadata_batch* recv_initial_metadata;
+ // Original recv_initial_metadata_ready callback, invoked after our own.
+ grpc_closure* next_recv_initial_metadata_ready;
+
+ // Marks whether the workaround is active
+ bool workaround_active;
+};
+} // namespace
+
+// Find the user agent metadata element in the batch
+static bool get_user_agent_mdelem(const grpc_metadata_batch* batch,
+ grpc_mdelem* md) {
+ if (batch->idx.named.user_agent != nullptr) {
+ *md = batch->idx.named.user_agent->md;
+ return true;
+ }
+ return false;
+}
+
+// Callback invoked when we receive an initial metadata.
+static void recv_initial_metadata_ready(void* user_data, grpc_error* error) {
+ grpc_call_element* elem = static_cast<grpc_call_element*>(user_data);
+ call_data* calld = static_cast<call_data*>(elem->call_data);
+
+ if (GRPC_ERROR_NONE == error) {
+ grpc_mdelem md;
+ if (get_user_agent_mdelem(calld->recv_initial_metadata, &md)) {
+ grpc_workaround_user_agent_md* user_agent_md = grpc_parse_user_agent(md);
+ if (user_agent_md
+ ->workaround_active[GRPC_WORKAROUND_ID_CRONET_COMPRESSION]) {
+ calld->workaround_active = true;
+ }
+ }
+ }
+
+ // Invoke the next callback.
+ GRPC_CLOSURE_RUN(calld->next_recv_initial_metadata_ready,
+ GRPC_ERROR_REF(error));
+}
+
+// Start transport stream op.
+static void start_transport_stream_op_batch(
+ grpc_call_element* elem, grpc_transport_stream_op_batch* op) {
+ call_data* calld = static_cast<call_data*>(elem->call_data);
+
+ // Inject callback for receiving initial metadata
+ if (op->recv_initial_metadata) {
+ calld->next_recv_initial_metadata_ready =
+ op->payload->recv_initial_metadata.recv_initial_metadata_ready;
+ op->payload->recv_initial_metadata.recv_initial_metadata_ready =
+ &calld->recv_initial_metadata_ready;
+ calld->recv_initial_metadata =
+ op->payload->recv_initial_metadata.recv_initial_metadata;
+ }
+
+ if (op->send_message) {
+ /* Send message happens after client's user-agent (initial metadata) is
+ * received, so workaround_active must be set already */
+ if (calld->workaround_active) {
+ op->payload->send_message.send_message->set_flags(
+ op->payload->send_message.send_message->flags() |
+ GRPC_WRITE_NO_COMPRESS);
+ }
+ }
+
+ // Chain to the next filter.
+ grpc_call_next_op(elem, op);
+}
+
+// Constructor for call_data.
+static grpc_error* init_call_elem(grpc_call_element* elem,
+ const grpc_call_element_args* args) {
+ call_data* calld = static_cast<call_data*>(elem->call_data);
+ calld->next_recv_initial_metadata_ready = nullptr;
+ calld->workaround_active = false;
+ GRPC_CLOSURE_INIT(&calld->recv_initial_metadata_ready,
+ recv_initial_metadata_ready, elem,
+ grpc_schedule_on_exec_ctx);
+ return GRPC_ERROR_NONE;
+}
+
+// Destructor for call_data.
+static void destroy_call_elem(grpc_call_element* elem,
+ const grpc_call_final_info* final_info,
+ grpc_closure* ignored) {}
+
+// Constructor for channel_data.
+static grpc_error* init_channel_elem(grpc_channel_element* elem,
+ grpc_channel_element_args* args) {
+ return GRPC_ERROR_NONE;
+}
+
+// Destructor for channel_data.
+static void destroy_channel_elem(grpc_channel_element* elem) {}
+
+// Parse the user agent
+static bool parse_user_agent(grpc_mdelem md) {
+ const char grpc_objc_specifier[] = "grpc-objc/";
+ const size_t grpc_objc_specifier_len = sizeof(grpc_objc_specifier) - 1;
+ const char cronet_specifier[] = "cronet_http";
+ const size_t cronet_specifier_len = sizeof(cronet_specifier) - 1;
+
+ char* user_agent_str = grpc_slice_to_c_string(GRPC_MDVALUE(md));
+ bool grpc_objc_specifier_seen = false;
+ bool cronet_specifier_seen = false;
+ char *major_version_str = user_agent_str, *minor_version_str;
+ long major_version = 0, minor_version = 0;
+
+ char* head = strtok(user_agent_str, " ");
+ while (head != nullptr) {
+ if (!grpc_objc_specifier_seen &&
+ 0 == strncmp(head, grpc_objc_specifier, grpc_objc_specifier_len)) {
+ major_version_str = head + grpc_objc_specifier_len;
+ grpc_objc_specifier_seen = true;
+ } else if (grpc_objc_specifier_seen &&
+ 0 == strncmp(head, cronet_specifier, cronet_specifier_len)) {
+ cronet_specifier_seen = true;
+ break;
+ }
+
+ head = strtok(nullptr, " ");
+ }
+ if (grpc_objc_specifier_seen) {
+ major_version_str = strtok(major_version_str, ".");
+ minor_version_str = strtok(nullptr, ".");
+ major_version = atol(major_version_str);
+ minor_version = atol(minor_version_str);
+ }
+
+ gpr_free(user_agent_str);
+ return (grpc_objc_specifier_seen && cronet_specifier_seen &&
+ (major_version < 1 || (major_version == 1 && minor_version <= 3)));
+}
+
+const grpc_channel_filter grpc_workaround_cronet_compression_filter = {
+ start_transport_stream_op_batch,
+ grpc_channel_next_op,
+ sizeof(call_data),
+ init_call_elem,
+ grpc_call_stack_ignore_set_pollset_or_pollset_set,
+ destroy_call_elem,
+ 0,
+ init_channel_elem,
+ destroy_channel_elem,
+ grpc_channel_next_get_info,
+ "workaround_cronet_compression"};
+
+static bool register_workaround_cronet_compression(
+ grpc_channel_stack_builder* builder, void* arg) {
+ const grpc_channel_args* channel_args =
+ grpc_channel_stack_builder_get_channel_arguments(builder);
+ const grpc_arg* a = grpc_channel_args_find(
+ channel_args, GRPC_ARG_WORKAROUND_CRONET_COMPRESSION);
+ if (a == nullptr) {
+ return true;
+ }
+ if (grpc_channel_arg_get_bool(a, false) == false) {
+ return true;
+ }
+ return grpc_channel_stack_builder_prepend_filter(
+ builder, &grpc_workaround_cronet_compression_filter, nullptr, nullptr);
+}
+
+void grpc_workaround_cronet_compression_filter_init(void) {
+ grpc_channel_init_register_stage(
+ GRPC_SERVER_CHANNEL, GRPC_WORKAROUND_PRIORITY_HIGH,
+ register_workaround_cronet_compression, nullptr);
+ grpc_register_workaround(GRPC_WORKAROUND_ID_CRONET_COMPRESSION,
+ parse_user_agent);
+}
+
+void grpc_workaround_cronet_compression_filter_shutdown(void) {}
git://repos.xcallymotion.com / motion2.git / blobdiff