| // |
| // 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 <grpc/support/port_platform.h> |
| |
| #include "src/core/ext/filters/message_size/message_size_filter.h" |
| |
| #include <limits.h> |
| #include <string.h> |
| |
| #include <grpc/impl/codegen/grpc_types.h> |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| #include <grpc/support/string_util.h> |
| |
| #include "src/core/lib/channel/channel_args.h" |
| #include "src/core/lib/channel/channel_stack_builder.h" |
| #include "src/core/lib/gpr/string.h" |
| #include "src/core/lib/gprpp/ref_counted.h" |
| #include "src/core/lib/gprpp/ref_counted_ptr.h" |
| #include "src/core/lib/surface/channel_init.h" |
| #include "src/core/lib/transport/service_config.h" |
| |
| typedef struct { |
| int max_send_size; |
| int max_recv_size; |
| } message_size_limits; |
| |
| namespace grpc_core { |
| namespace { |
| |
| class MessageSizeLimits : public RefCounted<MessageSizeLimits> { |
| public: |
| static RefCountedPtr<MessageSizeLimits> CreateFromJson(const grpc_json* json); |
| |
| const message_size_limits& limits() const { return limits_; } |
| |
| private: |
| // So New() can call our private ctor. |
| template <typename T, typename... Args> |
| friend T* grpc_core::New(Args&&... args); |
| |
| MessageSizeLimits(int max_send_size, int max_recv_size) { |
| limits_.max_send_size = max_send_size; |
| limits_.max_recv_size = max_recv_size; |
| } |
| |
| message_size_limits limits_; |
| }; |
| |
| RefCountedPtr<MessageSizeLimits> MessageSizeLimits::CreateFromJson( |
| const grpc_json* json) { |
| int max_request_message_bytes = -1; |
| int max_response_message_bytes = -1; |
| for (grpc_json* field = json->child; field != nullptr; field = field->next) { |
| if (field->key == nullptr) continue; |
| if (strcmp(field->key, "maxRequestMessageBytes") == 0) { |
| if (max_request_message_bytes >= 0) return nullptr; // Duplicate. |
| if (field->type != GRPC_JSON_STRING && field->type != GRPC_JSON_NUMBER) { |
| return nullptr; |
| } |
| max_request_message_bytes = gpr_parse_nonnegative_int(field->value); |
| if (max_request_message_bytes == -1) return nullptr; |
| } else if (strcmp(field->key, "maxResponseMessageBytes") == 0) { |
| if (max_response_message_bytes >= 0) return nullptr; // Duplicate. |
| if (field->type != GRPC_JSON_STRING && field->type != GRPC_JSON_NUMBER) { |
| return nullptr; |
| } |
| max_response_message_bytes = gpr_parse_nonnegative_int(field->value); |
| if (max_response_message_bytes == -1) return nullptr; |
| } |
| } |
| return MakeRefCounted<MessageSizeLimits>(max_request_message_bytes, |
| max_response_message_bytes); |
| } |
| |
| } // namespace |
| } // namespace grpc_core |
| |
| static void recv_message_ready(void* user_data, grpc_error* error); |
| static void recv_trailing_metadata_ready(void* user_data, grpc_error* error); |
| |
| namespace { |
| |
| struct channel_data { |
| message_size_limits limits; |
| // Maps path names to refcounted_message_size_limits structs. |
| grpc_core::RefCountedPtr<grpc_core::SliceHashTable< |
| grpc_core::RefCountedPtr<grpc_core::MessageSizeLimits>>> |
| method_limit_table; |
| }; |
| |
| struct call_data { |
| call_data(grpc_call_element* elem, const channel_data& chand, |
| const grpc_call_element_args& args) |
| : call_combiner(args.call_combiner), limits(chand.limits) { |
| GRPC_CLOSURE_INIT(&recv_message_ready, ::recv_message_ready, elem, |
| grpc_schedule_on_exec_ctx); |
| GRPC_CLOSURE_INIT(&recv_trailing_metadata_ready, |
| ::recv_trailing_metadata_ready, elem, |
| grpc_schedule_on_exec_ctx); |
| // Get max sizes from channel data, then merge in per-method config values. |
| // Note: Per-method config is only available on the client, so we |
| // apply the max request size to the send limit and the max response |
| // size to the receive limit. |
| if (chand.method_limit_table != nullptr) { |
| grpc_core::RefCountedPtr<grpc_core::MessageSizeLimits> limits = |
| grpc_core::ServiceConfig::MethodConfigTableLookup( |
| *chand.method_limit_table, args.path); |
| if (limits != nullptr) { |
| if (limits->limits().max_send_size >= 0 && |
| (limits->limits().max_send_size < this->limits.max_send_size || |
| this->limits.max_send_size < 0)) { |
| this->limits.max_send_size = limits->limits().max_send_size; |
| } |
| if (limits->limits().max_recv_size >= 0 && |
| (limits->limits().max_recv_size < this->limits.max_recv_size || |
| this->limits.max_recv_size < 0)) { |
| this->limits.max_recv_size = limits->limits().max_recv_size; |
| } |
| } |
| } |
| } |
| |
| ~call_data() { GRPC_ERROR_UNREF(error); } |
| |
| grpc_call_combiner* call_combiner; |
| message_size_limits limits; |
| // Receive closures are chained: we inject this closure as the |
| // recv_message_ready up-call on transport_stream_op, and remember to |
| // call our next_recv_message_ready member after handling it. |
| grpc_closure recv_message_ready; |
| grpc_closure recv_trailing_metadata_ready; |
| // The error caused by a message that is too large, or GRPC_ERROR_NONE |
| grpc_error* error = GRPC_ERROR_NONE; |
| // Used by recv_message_ready. |
| grpc_core::OrphanablePtr<grpc_core::ByteStream>* recv_message = nullptr; |
| // Original recv_message_ready callback, invoked after our own. |
| grpc_closure* next_recv_message_ready = nullptr; |
| // Original recv_trailing_metadata callback, invoked after our own. |
| grpc_closure* original_recv_trailing_metadata_ready; |
| bool seen_recv_trailing_metadata = false; |
| grpc_error* recv_trailing_metadata_error; |
| }; |
| |
| } // namespace |
| |
| // Callback invoked when we receive a message. Here we check the max |
| // receive message size. |
| static void recv_message_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 (*calld->recv_message != nullptr && calld->limits.max_recv_size >= 0 && |
| (*calld->recv_message)->length() > |
| static_cast<size_t>(calld->limits.max_recv_size)) { |
| char* message_string; |
| gpr_asprintf(&message_string, |
| "Received message larger than max (%u vs. %d)", |
| (*calld->recv_message)->length(), calld->limits.max_recv_size); |
| grpc_error* new_error = grpc_error_set_int( |
| GRPC_ERROR_CREATE_FROM_COPIED_STRING(message_string), |
| GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_RESOURCE_EXHAUSTED); |
| GRPC_ERROR_UNREF(calld->error); |
| if (error == GRPC_ERROR_NONE) { |
| error = new_error; |
| } else { |
| error = grpc_error_add_child(error, new_error); |
| } |
| calld->error = GRPC_ERROR_REF(error); |
| gpr_free(message_string); |
| } else { |
| GRPC_ERROR_REF(error); |
| } |
| // Invoke the next callback. |
| grpc_closure* closure = calld->next_recv_message_ready; |
| calld->next_recv_message_ready = nullptr; |
| if (calld->seen_recv_trailing_metadata) { |
| /* We might potentially see another RECV_MESSAGE op. In that case, we do not |
| * want to run the recv_trailing_metadata_ready closure again. The newer |
| * RECV_MESSAGE op cannot cause any errors since the transport has already |
| * invoked the recv_trailing_metadata_ready closure and all further |
| * RECV_MESSAGE ops will get null payloads. */ |
| calld->seen_recv_trailing_metadata = false; |
| GRPC_CALL_COMBINER_START(calld->call_combiner, |
| &calld->recv_trailing_metadata_ready, |
| calld->recv_trailing_metadata_error, |
| "continue recv_trailing_metadata_ready"); |
| } |
| GRPC_CLOSURE_RUN(closure, error); |
| } |
| |
| // Callback invoked on completion of recv_trailing_metadata |
| // Notifies the recv_trailing_metadata batch of any message size failures |
| static void recv_trailing_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 (calld->next_recv_message_ready != nullptr) { |
| calld->seen_recv_trailing_metadata = true; |
| calld->recv_trailing_metadata_error = GRPC_ERROR_REF(error); |
| GRPC_CALL_COMBINER_STOP(calld->call_combiner, |
| "deferring recv_trailing_metadata_ready until " |
| "after recv_message_ready"); |
| return; |
| } |
| error = |
| grpc_error_add_child(GRPC_ERROR_REF(error), GRPC_ERROR_REF(calld->error)); |
| // Invoke the next callback. |
| GRPC_CLOSURE_RUN(calld->original_recv_trailing_metadata_ready, 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); |
| // Check max send message size. |
| if (op->send_message && calld->limits.max_send_size >= 0 && |
| op->payload->send_message.send_message->length() > |
| static_cast<size_t>(calld->limits.max_send_size)) { |
| char* message_string; |
| gpr_asprintf(&message_string, "Sent message larger than max (%u vs. %d)", |
| op->payload->send_message.send_message->length(), |
| calld->limits.max_send_size); |
| grpc_transport_stream_op_batch_finish_with_failure( |
| op, |
| grpc_error_set_int(GRPC_ERROR_CREATE_FROM_COPIED_STRING(message_string), |
| GRPC_ERROR_INT_GRPC_STATUS, |
| GRPC_STATUS_RESOURCE_EXHAUSTED), |
| calld->call_combiner); |
| gpr_free(message_string); |
| return; |
| } |
| // Inject callback for receiving a message. |
| if (op->recv_message) { |
| calld->next_recv_message_ready = |
| op->payload->recv_message.recv_message_ready; |
| calld->recv_message = op->payload->recv_message.recv_message; |
| op->payload->recv_message.recv_message_ready = &calld->recv_message_ready; |
| } |
| // Inject callback for receiving trailing metadata. |
| if (op->recv_trailing_metadata) { |
| calld->original_recv_trailing_metadata_ready = |
| op->payload->recv_trailing_metadata.recv_trailing_metadata_ready; |
| op->payload->recv_trailing_metadata.recv_trailing_metadata_ready = |
| &calld->recv_trailing_metadata_ready; |
| } |
| // 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) { |
| channel_data* chand = static_cast<channel_data*>(elem->channel_data); |
| new (elem->call_data) call_data(elem, *chand, *args); |
| 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) { |
| call_data* calld = (call_data*)elem->call_data; |
| calld->~call_data(); |
| } |
| |
| static int default_size(const grpc_channel_args* args, |
| int without_minimal_stack) { |
| if (grpc_channel_args_want_minimal_stack(args)) { |
| return -1; |
| } |
| return without_minimal_stack; |
| } |
| |
| message_size_limits get_message_size_limits( |
| const grpc_channel_args* channel_args) { |
| message_size_limits lim; |
| lim.max_send_size = |
| default_size(channel_args, GRPC_DEFAULT_MAX_SEND_MESSAGE_LENGTH); |
| lim.max_recv_size = |
| default_size(channel_args, GRPC_DEFAULT_MAX_RECV_MESSAGE_LENGTH); |
| for (size_t i = 0; i < channel_args->num_args; ++i) { |
| if (strcmp(channel_args->args[i].key, GRPC_ARG_MAX_SEND_MESSAGE_LENGTH) == |
| 0) { |
| const grpc_integer_options options = {lim.max_send_size, -1, INT_MAX}; |
| lim.max_send_size = |
| grpc_channel_arg_get_integer(&channel_args->args[i], options); |
| } |
| if (strcmp(channel_args->args[i].key, |
| GRPC_ARG_MAX_RECEIVE_MESSAGE_LENGTH) == 0) { |
| const grpc_integer_options options = {lim.max_recv_size, -1, INT_MAX}; |
| lim.max_recv_size = |
| grpc_channel_arg_get_integer(&channel_args->args[i], options); |
| } |
| } |
| return lim; |
| } |
| |
| // Constructor for channel_data. |
| static grpc_error* init_channel_elem(grpc_channel_element* elem, |
| grpc_channel_element_args* args) { |
| GPR_ASSERT(!args->is_last); |
| channel_data* chand = static_cast<channel_data*>(elem->channel_data); |
| chand->limits = get_message_size_limits(args->channel_args); |
| // Get method config table from channel args. |
| const grpc_arg* channel_arg = |
| grpc_channel_args_find(args->channel_args, GRPC_ARG_SERVICE_CONFIG); |
| const char* service_config_str = grpc_channel_arg_get_string(channel_arg); |
| if (service_config_str != nullptr) { |
| grpc_core::UniquePtr<grpc_core::ServiceConfig> service_config = |
| grpc_core::ServiceConfig::Create(service_config_str); |
| if (service_config != nullptr) { |
| chand->method_limit_table = service_config->CreateMethodConfigTable( |
| grpc_core::MessageSizeLimits::CreateFromJson); |
| } |
| } |
| return GRPC_ERROR_NONE; |
| } |
| |
| // Destructor for channel_data. |
| static void destroy_channel_elem(grpc_channel_element* elem) { |
| channel_data* chand = static_cast<channel_data*>(elem->channel_data); |
| chand->method_limit_table.reset(); |
| } |
| |
| const grpc_channel_filter grpc_message_size_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, |
| sizeof(channel_data), |
| init_channel_elem, |
| destroy_channel_elem, |
| grpc_channel_next_get_info, |
| "message_size"}; |
| |
| static bool maybe_add_message_size_filter(grpc_channel_stack_builder* builder, |
| void* arg) { |
| const grpc_channel_args* channel_args = |
| grpc_channel_stack_builder_get_channel_arguments(builder); |
| bool enable = false; |
| message_size_limits lim = get_message_size_limits(channel_args); |
| if (lim.max_send_size != -1 || lim.max_recv_size != -1) { |
| enable = true; |
| } |
| const grpc_arg* a = |
| grpc_channel_args_find(channel_args, GRPC_ARG_SERVICE_CONFIG); |
| if (a != nullptr) { |
| enable = true; |
| } |
| if (enable) { |
| return grpc_channel_stack_builder_prepend_filter( |
| builder, &grpc_message_size_filter, nullptr, nullptr); |
| } else { |
| return true; |
| } |
| } |
| |
| void grpc_message_size_filter_init(void) { |
| grpc_channel_init_register_stage(GRPC_CLIENT_SUBCHANNEL, |
| GRPC_CHANNEL_INIT_BUILTIN_PRIORITY, |
| maybe_add_message_size_filter, nullptr); |
| grpc_channel_init_register_stage(GRPC_CLIENT_DIRECT_CHANNEL, |
| GRPC_CHANNEL_INIT_BUILTIN_PRIORITY, |
| maybe_add_message_size_filter, nullptr); |
| grpc_channel_init_register_stage(GRPC_SERVER_CHANNEL, |
| GRPC_CHANNEL_INIT_BUILTIN_PRIORITY, |
| maybe_add_message_size_filter, nullptr); |
| } |
| |
| void grpc_message_size_filter_shutdown(void) {} |
