| /* |
| * Copyright 2015, 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/http_client_filter.h" |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| #include <grpc/support/string_util.h> |
| #include <string.h> |
| #include "src/core/lib/profiling/timers.h" |
| #include "src/core/lib/support/string.h" |
| #include "src/core/lib/transport/static_metadata.h" |
| #include "src/core/lib/transport/transport_impl.h" |
| |
| #define EXPECTED_CONTENT_TYPE "application/grpc" |
| #define EXPECTED_CONTENT_TYPE_LENGTH sizeof(EXPECTED_CONTENT_TYPE) - 1 |
| |
| typedef struct call_data { |
| grpc_linked_mdelem method; |
| grpc_linked_mdelem scheme; |
| grpc_linked_mdelem authority; |
| grpc_linked_mdelem te_trailers; |
| grpc_linked_mdelem content_type; |
| grpc_linked_mdelem user_agent; |
| |
| grpc_metadata_batch *recv_initial_metadata; |
| |
| /** Closure to call when finished with the hc_on_recv hook */ |
| grpc_closure *on_done_recv; |
| /** Receive closures are chained: we inject this closure as the on_done_recv |
| up-call on transport_op, and remember to call our on_done_recv member |
| after handling it. */ |
| grpc_closure hc_on_recv; |
| } call_data; |
| |
| typedef struct channel_data { |
| grpc_mdelem *static_scheme; |
| grpc_mdelem *user_agent; |
| } channel_data; |
| |
| typedef struct { |
| grpc_call_element *elem; |
| grpc_exec_ctx *exec_ctx; |
| } client_recv_filter_args; |
| |
| static grpc_mdelem *client_recv_filter(void *user_data, grpc_mdelem *md) { |
| client_recv_filter_args *a = user_data; |
| if (md == GRPC_MDELEM_STATUS_200) { |
| return NULL; |
| } else if (md->key == GRPC_MDSTR_STATUS) { |
| grpc_call_element_send_cancel(a->exec_ctx, a->elem); |
| return NULL; |
| } else if (md == GRPC_MDELEM_CONTENT_TYPE_APPLICATION_SLASH_GRPC) { |
| return NULL; |
| } else if (md->key == GRPC_MDSTR_CONTENT_TYPE) { |
| const char *value_str = grpc_mdstr_as_c_string(md->value); |
| if (strncmp(value_str, EXPECTED_CONTENT_TYPE, |
| EXPECTED_CONTENT_TYPE_LENGTH) == 0 && |
| (value_str[EXPECTED_CONTENT_TYPE_LENGTH] == '+' || |
| value_str[EXPECTED_CONTENT_TYPE_LENGTH] == ';')) { |
| /* Although the C implementation doesn't (currently) generate them, |
| any custom +-suffix is explicitly valid. */ |
| /* TODO(klempner): We should consider preallocating common values such |
| as +proto or +json, or at least stashing them if we see them. */ |
| /* TODO(klempner): Should we be surfacing this to application code? */ |
| } else { |
| /* TODO(klempner): We're currently allowing this, but we shouldn't |
| see it without a proxy so log for now. */ |
| gpr_log(GPR_INFO, "Unexpected content-type '%s'", value_str); |
| } |
| return NULL; |
| } |
| return md; |
| } |
| |
| static void hc_on_recv(grpc_exec_ctx *exec_ctx, void *user_data, |
| grpc_error *error) { |
| grpc_call_element *elem = user_data; |
| call_data *calld = elem->call_data; |
| client_recv_filter_args a; |
| a.elem = elem; |
| a.exec_ctx = exec_ctx; |
| grpc_metadata_batch_filter(calld->recv_initial_metadata, client_recv_filter, |
| &a); |
| calld->on_done_recv->cb(exec_ctx, calld->on_done_recv->cb_arg, error); |
| } |
| |
| static grpc_mdelem *client_strip_filter(void *user_data, grpc_mdelem *md) { |
| /* eat the things we'd like to set ourselves */ |
| if (md->key == GRPC_MDSTR_METHOD) return NULL; |
| if (md->key == GRPC_MDSTR_SCHEME) return NULL; |
| if (md->key == GRPC_MDSTR_TE) return NULL; |
| if (md->key == GRPC_MDSTR_CONTENT_TYPE) return NULL; |
| if (md->key == GRPC_MDSTR_USER_AGENT) return NULL; |
| return md; |
| } |
| |
| static void hc_mutate_op(grpc_call_element *elem, |
| grpc_transport_stream_op *op) { |
| /* grab pointers to our data from the call element */ |
| call_data *calld = elem->call_data; |
| channel_data *channeld = elem->channel_data; |
| if (op->send_initial_metadata != NULL) { |
| grpc_metadata_batch_filter(op->send_initial_metadata, client_strip_filter, |
| elem); |
| /* Send : prefixed headers, which have to be before any application |
| layer headers. */ |
| grpc_metadata_batch_add_head( |
| op->send_initial_metadata, &calld->method, |
| op->send_initial_metadata_flags & |
| GRPC_INITIAL_METADATA_IDEMPOTENT_REQUEST |
| ? GRPC_MDELEM_METHOD_PUT |
| : GRPC_MDELEM_METHOD_POST); |
| grpc_metadata_batch_add_head(op->send_initial_metadata, &calld->scheme, |
| channeld->static_scheme); |
| grpc_metadata_batch_add_tail(op->send_initial_metadata, &calld->te_trailers, |
| GRPC_MDELEM_TE_TRAILERS); |
| grpc_metadata_batch_add_tail( |
| op->send_initial_metadata, &calld->content_type, |
| GRPC_MDELEM_CONTENT_TYPE_APPLICATION_SLASH_GRPC); |
| grpc_metadata_batch_add_tail(op->send_initial_metadata, &calld->user_agent, |
| GRPC_MDELEM_REF(channeld->user_agent)); |
| } |
| |
| if (op->recv_initial_metadata != NULL) { |
| /* substitute our callback for the higher callback */ |
| calld->recv_initial_metadata = op->recv_initial_metadata; |
| calld->on_done_recv = op->recv_initial_metadata_ready; |
| op->recv_initial_metadata_ready = &calld->hc_on_recv; |
| } |
| } |
| |
| static void hc_start_transport_op(grpc_exec_ctx *exec_ctx, |
| grpc_call_element *elem, |
| grpc_transport_stream_op *op) { |
| GPR_TIMER_BEGIN("hc_start_transport_op", 0); |
| GRPC_CALL_LOG_OP(GPR_INFO, elem, op); |
| hc_mutate_op(elem, op); |
| GPR_TIMER_END("hc_start_transport_op", 0); |
| grpc_call_next_op(exec_ctx, elem, op); |
| } |
| |
| /* Constructor for call_data */ |
| static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem, |
| grpc_call_element_args *args) { |
| call_data *calld = elem->call_data; |
| calld->on_done_recv = NULL; |
| grpc_closure_init(&calld->hc_on_recv, hc_on_recv, elem); |
| } |
| |
| /* Destructor for call_data */ |
| static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem, |
| const grpc_call_stats *stats, void *ignored) {} |
| |
| static grpc_mdelem *scheme_from_args(const grpc_channel_args *args) { |
| unsigned i; |
| size_t j; |
| grpc_mdelem *valid_schemes[] = {GRPC_MDELEM_SCHEME_HTTP, |
| GRPC_MDELEM_SCHEME_HTTPS}; |
| if (args != NULL) { |
| for (i = 0; i < args->num_args; ++i) { |
| if (args->args[i].type == GRPC_ARG_STRING && |
| strcmp(args->args[i].key, GRPC_ARG_HTTP2_SCHEME) == 0) { |
| for (j = 0; j < GPR_ARRAY_SIZE(valid_schemes); j++) { |
| if (0 == strcmp(grpc_mdstr_as_c_string(valid_schemes[j]->value), |
| args->args[i].value.string)) { |
| return valid_schemes[j]; |
| } |
| } |
| } |
| } |
| } |
| return GRPC_MDELEM_SCHEME_HTTP; |
| } |
| |
| static grpc_mdstr *user_agent_from_args(const grpc_channel_args *args, |
| const char *transport_name) { |
| gpr_strvec v; |
| size_t i; |
| int is_first = 1; |
| char *tmp; |
| grpc_mdstr *result; |
| |
| gpr_strvec_init(&v); |
| |
| for (i = 0; args && i < args->num_args; i++) { |
| if (0 == strcmp(args->args[i].key, GRPC_ARG_PRIMARY_USER_AGENT_STRING)) { |
| if (args->args[i].type != GRPC_ARG_STRING) { |
| gpr_log(GPR_ERROR, "Channel argument '%s' should be a string", |
| GRPC_ARG_PRIMARY_USER_AGENT_STRING); |
| } else { |
| if (!is_first) gpr_strvec_add(&v, gpr_strdup(" ")); |
| is_first = 0; |
| gpr_strvec_add(&v, gpr_strdup(args->args[i].value.string)); |
| } |
| } |
| } |
| |
| gpr_asprintf(&tmp, "%sgrpc-c/%s (%s; %s)", is_first ? "" : " ", |
| grpc_version_string(), GPR_PLATFORM_STRING, transport_name); |
| is_first = 0; |
| gpr_strvec_add(&v, tmp); |
| |
| for (i = 0; args && i < args->num_args; i++) { |
| if (0 == strcmp(args->args[i].key, GRPC_ARG_SECONDARY_USER_AGENT_STRING)) { |
| if (args->args[i].type != GRPC_ARG_STRING) { |
| gpr_log(GPR_ERROR, "Channel argument '%s' should be a string", |
| GRPC_ARG_SECONDARY_USER_AGENT_STRING); |
| } else { |
| if (!is_first) gpr_strvec_add(&v, gpr_strdup(" ")); |
| is_first = 0; |
| gpr_strvec_add(&v, gpr_strdup(args->args[i].value.string)); |
| } |
| } |
| } |
| |
| tmp = gpr_strvec_flatten(&v, NULL); |
| gpr_strvec_destroy(&v); |
| result = grpc_mdstr_from_string(tmp); |
| gpr_free(tmp); |
| |
| return result; |
| } |
| |
| /* Constructor for channel_data */ |
| static void init_channel_elem(grpc_exec_ctx *exec_ctx, |
| grpc_channel_element *elem, |
| grpc_channel_element_args *args) { |
| channel_data *chand = elem->channel_data; |
| GPR_ASSERT(!args->is_last); |
| GPR_ASSERT(args->optional_transport != NULL); |
| chand->static_scheme = scheme_from_args(args->channel_args); |
| chand->user_agent = grpc_mdelem_from_metadata_strings( |
| GRPC_MDSTR_USER_AGENT, |
| user_agent_from_args(args->channel_args, |
| args->optional_transport->vtable->name)); |
| } |
| |
| /* Destructor for channel data */ |
| static void destroy_channel_elem(grpc_exec_ctx *exec_ctx, |
| grpc_channel_element *elem) { |
| channel_data *chand = elem->channel_data; |
| GRPC_MDELEM_UNREF(chand->user_agent); |
| } |
| |
| const grpc_channel_filter grpc_http_client_filter = { |
| hc_start_transport_op, |
| 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_call_next_get_peer, |
| "http-client"}; |