| /* |
| * |
| * 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/channel/http_server_filter.h" |
| |
| #include <string.h> |
| #include <grpc/grpc_http.h> |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| |
| typedef struct { |
| grpc_mdelem *path; |
| grpc_mdelem *content_type; |
| grpc_byte_buffer *content; |
| } gettable; |
| |
| typedef struct call_data { |
| gpr_uint8 got_initial_metadata; |
| gpr_uint8 seen_path; |
| gpr_uint8 seen_post; |
| gpr_uint8 sent_status; |
| gpr_uint8 seen_scheme; |
| gpr_uint8 seen_te_trailers; |
| grpc_linked_mdelem status; |
| } call_data; |
| |
| typedef struct channel_data { |
| grpc_mdelem *te_trailers; |
| grpc_mdelem *method_post; |
| grpc_mdelem *http_scheme; |
| grpc_mdelem *https_scheme; |
| /* TODO(klempner): Remove this once we stop using it */ |
| grpc_mdelem *grpc_scheme; |
| grpc_mdelem *content_type; |
| grpc_mdelem *status_ok; |
| grpc_mdelem *status_not_found; |
| grpc_mdstr *path_key; |
| grpc_mdstr *authority_key; |
| grpc_mdstr *host_key; |
| |
| grpc_mdctx *mdctx; |
| |
| size_t gettable_count; |
| gettable *gettables; |
| } channel_data; |
| |
| /* used to silence 'variable not used' warnings */ |
| static void ignore_unused(void *ignored) {} |
| |
| static grpc_mdelem *server_filter(void *user_data, grpc_mdelem *md) { |
| grpc_call_element *elem = user_data; |
| channel_data *channeld = elem->channel_data; |
| call_data *calld = elem->call_data; |
| |
| /* Check if it is one of the headers we care about. */ |
| if (md == channeld->te_trailers || md == channeld->method_post || |
| md == channeld->http_scheme || md == channeld->https_scheme || |
| md == channeld->grpc_scheme || md == channeld->content_type) { |
| /* swallow it */ |
| if (md == channeld->method_post) { |
| calld->seen_post = 1; |
| } else if (md->key == channeld->http_scheme->key) { |
| calld->seen_scheme = 1; |
| } else if (md == channeld->te_trailers) { |
| calld->seen_te_trailers = 1; |
| } |
| /* TODO(klempner): Track that we've seen all the headers we should |
| require */ |
| return NULL; |
| } else if (md->key == channeld->content_type->key) { |
| if (strncmp(grpc_mdstr_as_c_string(md->value), "application/grpc+", 17) == |
| 0) { |
| /* 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", |
| channeld->content_type->key); |
| } |
| return NULL; |
| } else if (md->key == channeld->te_trailers->key || |
| md->key == channeld->method_post->key || |
| md->key == channeld->http_scheme->key || |
| md->key == channeld->content_type->key) { |
| gpr_log(GPR_ERROR, "Invalid %s: header: '%s'", |
| grpc_mdstr_as_c_string(md->key), grpc_mdstr_as_c_string(md->value)); |
| /* swallow it and error everything out. */ |
| /* TODO(klempner): We ought to generate more descriptive error messages |
| on the wire here. */ |
| grpc_call_element_send_cancel(elem); |
| return NULL; |
| } else if (md->key == channeld->path_key) { |
| if (calld->seen_path) { |
| gpr_log(GPR_ERROR, "Received :path twice"); |
| return NULL; |
| } |
| calld->seen_path = 1; |
| return md; |
| } else if (md->key == channeld->host_key) { |
| /* translate host to :authority since :authority may be |
| omitted */ |
| grpc_mdelem *authority = grpc_mdelem_from_metadata_strings( |
| channeld->mdctx, grpc_mdstr_ref(channeld->authority_key), |
| grpc_mdstr_ref(md->value)); |
| grpc_mdelem_unref(md); |
| return authority; |
| } else { |
| return md; |
| } |
| } |
| |
| /* Called either: |
| - in response to an API call (or similar) from above, to send something |
| - a network event (or similar) from below, to receive something |
| op contains type and call direction information, in addition to the data |
| that is being sent or received. */ |
| static void call_op(grpc_call_element *elem, grpc_call_element *from_elem, |
| grpc_call_op *op) { |
| /* grab pointers to our data from the call element */ |
| call_data *calld = elem->call_data; |
| channel_data *channeld = elem->channel_data; |
| GRPC_CALL_LOG_OP(GPR_INFO, elem, op); |
| |
| switch (op->type) { |
| case GRPC_RECV_METADATA: |
| grpc_metadata_batch_filter(&op->data.metadata, server_filter, elem); |
| if (!calld->got_initial_metadata) { |
| calld->got_initial_metadata = 1; |
| /* Have we seen the required http2 transport headers? |
| (:method, :scheme, content-type, with :path and :authority covered |
| at the channel level right now) */ |
| if (calld->seen_post && calld->seen_scheme && calld->seen_te_trailers && |
| calld->seen_path) { |
| grpc_call_next_op(elem, op); |
| } else { |
| if (!calld->seen_post) { |
| gpr_log(GPR_ERROR, "Missing :method header"); |
| } |
| if (!calld->seen_scheme) { |
| gpr_log(GPR_ERROR, "Missing :scheme header"); |
| } |
| if (!calld->seen_te_trailers) { |
| gpr_log(GPR_ERROR, "Missing te trailers header"); |
| } |
| /* Error this call out */ |
| grpc_metadata_batch_destroy(&op->data.metadata); |
| op->done_cb(op->user_data, GRPC_OP_OK); |
| grpc_call_element_send_cancel(elem); |
| } |
| } else { |
| grpc_call_next_op(elem, op); |
| } |
| break; |
| case GRPC_SEND_METADATA: |
| /* If we haven't sent status 200 yet, we need to so so because it needs to |
| come before any non : prefixed metadata. */ |
| if (!calld->sent_status) { |
| calld->sent_status = 1; |
| grpc_metadata_batch_add_head(&op->data.metadata, &calld->status, |
| grpc_mdelem_ref(channeld->status_ok)); |
| } |
| grpc_call_next_op(elem, op); |
| break; |
| default: |
| /* pass control up or down the stack depending on op->dir */ |
| grpc_call_next_op(elem, op); |
| break; |
| } |
| } |
| |
| /* Called on special channel events, such as disconnection or new incoming |
| calls on the server */ |
| static void channel_op(grpc_channel_element *elem, |
| grpc_channel_element *from_elem, grpc_channel_op *op) { |
| /* grab pointers to our data from the channel element */ |
| channel_data *channeld = elem->channel_data; |
| |
| ignore_unused(channeld); |
| |
| switch (op->type) { |
| default: |
| /* pass control up or down the stack depending on op->dir */ |
| grpc_channel_next_op(elem, op); |
| break; |
| } |
| } |
| |
| /* Constructor for call_data */ |
| static void init_call_elem(grpc_call_element *elem, |
| const void *server_transport_data) { |
| /* grab pointers to our data from the call element */ |
| call_data *calld = elem->call_data; |
| channel_data *channeld = elem->channel_data; |
| |
| ignore_unused(channeld); |
| |
| /* initialize members */ |
| memset(calld, 0, sizeof(*calld)); |
| } |
| |
| /* Destructor for call_data */ |
| static void destroy_call_elem(grpc_call_element *elem) {} |
| |
| /* Constructor for channel_data */ |
| static void init_channel_elem(grpc_channel_element *elem, |
| const grpc_channel_args *args, grpc_mdctx *mdctx, |
| int is_first, int is_last) { |
| size_t i; |
| size_t gettable_capacity = 0; |
| |
| /* grab pointers to our data from the channel element */ |
| channel_data *channeld = elem->channel_data; |
| |
| /* The first and the last filters tend to be implemented differently to |
| handle the case that there's no 'next' filter to call on the up or down |
| path */ |
| GPR_ASSERT(!is_first); |
| GPR_ASSERT(!is_last); |
| |
| /* initialize members */ |
| channeld->te_trailers = grpc_mdelem_from_strings(mdctx, "te", "trailers"); |
| channeld->status_ok = grpc_mdelem_from_strings(mdctx, ":status", "200"); |
| channeld->status_not_found = |
| grpc_mdelem_from_strings(mdctx, ":status", "404"); |
| channeld->method_post = grpc_mdelem_from_strings(mdctx, ":method", "POST"); |
| channeld->http_scheme = grpc_mdelem_from_strings(mdctx, ":scheme", "http"); |
| channeld->https_scheme = grpc_mdelem_from_strings(mdctx, ":scheme", "https"); |
| channeld->grpc_scheme = grpc_mdelem_from_strings(mdctx, ":scheme", "grpc"); |
| channeld->path_key = grpc_mdstr_from_string(mdctx, ":path"); |
| channeld->authority_key = grpc_mdstr_from_string(mdctx, ":authority"); |
| channeld->host_key = grpc_mdstr_from_string(mdctx, "host"); |
| channeld->content_type = |
| grpc_mdelem_from_strings(mdctx, "content-type", "application/grpc"); |
| |
| channeld->mdctx = mdctx; |
| |
| /* initialize http download support */ |
| channeld->gettable_count = 0; |
| channeld->gettables = NULL; |
| for (i = 0; i < args->num_args; i++) { |
| if (0 == strcmp(args->args[i].key, GRPC_ARG_SERVE_OVER_HTTP)) { |
| gettable *g; |
| gpr_slice slice; |
| grpc_http_server_page *p = args->args[i].value.pointer.p; |
| if (channeld->gettable_count == gettable_capacity) { |
| gettable_capacity = |
| GPR_MAX(gettable_capacity * 3 / 2, gettable_capacity + 1); |
| channeld->gettables = gpr_realloc(channeld->gettables, |
| gettable_capacity * sizeof(gettable)); |
| } |
| g = &channeld->gettables[channeld->gettable_count++]; |
| g->path = grpc_mdelem_from_strings(mdctx, ":path", p->path); |
| g->content_type = |
| grpc_mdelem_from_strings(mdctx, "content-type", p->content_type); |
| slice = gpr_slice_from_copied_string(p->content); |
| g->content = grpc_byte_buffer_create(&slice, 1); |
| gpr_slice_unref(slice); |
| } |
| } |
| } |
| |
| /* Destructor for channel data */ |
| static void destroy_channel_elem(grpc_channel_element *elem) { |
| size_t i; |
| |
| /* grab pointers to our data from the channel element */ |
| channel_data *channeld = elem->channel_data; |
| |
| for (i = 0; i < channeld->gettable_count; i++) { |
| grpc_mdelem_unref(channeld->gettables[i].path); |
| grpc_mdelem_unref(channeld->gettables[i].content_type); |
| grpc_byte_buffer_destroy(channeld->gettables[i].content); |
| } |
| gpr_free(channeld->gettables); |
| |
| grpc_mdelem_unref(channeld->te_trailers); |
| grpc_mdelem_unref(channeld->status_ok); |
| grpc_mdelem_unref(channeld->status_not_found); |
| grpc_mdelem_unref(channeld->method_post); |
| grpc_mdelem_unref(channeld->http_scheme); |
| grpc_mdelem_unref(channeld->https_scheme); |
| grpc_mdelem_unref(channeld->grpc_scheme); |
| grpc_mdelem_unref(channeld->content_type); |
| grpc_mdstr_unref(channeld->path_key); |
| grpc_mdstr_unref(channeld->authority_key); |
| grpc_mdstr_unref(channeld->host_key); |
| } |
| |
| const grpc_channel_filter grpc_http_server_filter = { |
| call_op, channel_op, sizeof(call_data), init_call_elem, destroy_call_elem, |
| sizeof(channel_data), init_channel_elem, destroy_channel_elem, |
| "http-server"}; |