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/*
*
* 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_server_filter.h"
#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <string.h>
#include "src/core/lib/profiling/timers.h"
#include "src/core/lib/security/util/b64.h"
#include "src/core/lib/slice/percent_encoding.h"
#include "src/core/lib/slice/slice_internal.h"
#include "src/core/lib/slice/slice_string_helpers.h"
#include "src/core/lib/transport/static_metadata.h"
#define EXPECTED_CONTENT_TYPE "application/grpc"
#define EXPECTED_CONTENT_TYPE_LENGTH sizeof(EXPECTED_CONTENT_TYPE) - 1
extern int grpc_http_trace;
typedef struct call_data {
grpc_linked_mdelem status;
grpc_linked_mdelem content_type;
/* did this request come with path query containing request payload */
bool seen_path_with_query;
/* flag to ensure payload_bin is delivered only once */
bool payload_bin_delivered;
grpc_metadata_batch *recv_initial_metadata;
bool *recv_idempotent_request;
bool *recv_cacheable_request;
/** Closure to call when finished with the hs_on_recv hook */
grpc_closure *on_done_recv;
/** Closure to call when we retrieve read message from the path URI
*/
grpc_closure *recv_message_ready;
grpc_closure *on_complete;
grpc_byte_stream **pp_recv_message;
grpc_slice_buffer read_slice_buffer;
grpc_slice_buffer_stream read_stream;
/** 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 hs_on_recv;
grpc_closure hs_on_complete;
grpc_closure hs_recv_message_ready;
} call_data;
typedef struct channel_data { uint8_t unused; } channel_data;
static grpc_error *server_filter_outgoing_metadata(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem,
grpc_metadata_batch *b) {
if (b->idx.named.grpc_message != NULL) {
grpc_slice pct_encoded_msg = grpc_percent_encode_slice(
GRPC_MDVALUE(b->idx.named.grpc_message->md),
grpc_compatible_percent_encoding_unreserved_bytes);
if (grpc_slice_is_equivalent(pct_encoded_msg,
GRPC_MDVALUE(b->idx.named.grpc_message->md))) {
grpc_slice_unref_internal(exec_ctx, pct_encoded_msg);
} else {
grpc_metadata_batch_set_value(exec_ctx, b->idx.named.grpc_message,
pct_encoded_msg);
}
}
return GRPC_ERROR_NONE;
}
static void add_error(const char *error_name, grpc_error **cumulative,
grpc_error *new) {
if (new == GRPC_ERROR_NONE) return;
if (*cumulative == GRPC_ERROR_NONE) {
*cumulative = GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_name);
}
*cumulative = grpc_error_add_child(*cumulative, new);
}
static grpc_error *server_filter_incoming_metadata(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem,
grpc_metadata_batch *b) {
call_data *calld = elem->call_data;
grpc_error *error = GRPC_ERROR_NONE;
static const char *error_name = "Failed processing incoming headers";
if (b->idx.named.method != NULL) {
if (grpc_mdelem_eq(b->idx.named.method->md, GRPC_MDELEM_METHOD_POST)) {
*calld->recv_idempotent_request = false;
*calld->recv_cacheable_request = false;
} else if (grpc_mdelem_eq(b->idx.named.method->md,
GRPC_MDELEM_METHOD_PUT)) {
*calld->recv_idempotent_request = true;
} else if (grpc_mdelem_eq(b->idx.named.method->md,
GRPC_MDELEM_METHOD_GET)) {
*calld->recv_cacheable_request = true;
} else {
add_error(error_name, &error,
grpc_attach_md_to_error(
GRPC_ERROR_CREATE_FROM_STATIC_STRING("Bad header"),
b->idx.named.method->md));
}
grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.method);
} else {
add_error(
error_name, &error,
grpc_error_set_str(
GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing header"),
GRPC_ERROR_STR_KEY, grpc_slice_from_static_string(":method")));
}
if (b->idx.named.te != NULL) {
if (!grpc_mdelem_eq(b->idx.named.te->md, GRPC_MDELEM_TE_TRAILERS)) {
add_error(error_name, &error,
grpc_attach_md_to_error(
GRPC_ERROR_CREATE_FROM_STATIC_STRING("Bad header"),
b->idx.named.te->md));
}
grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.te);
} else {
add_error(error_name, &error,
grpc_error_set_str(
GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing header"),
GRPC_ERROR_STR_KEY, grpc_slice_from_static_string("te")));
}
if (b->idx.named.scheme != NULL) {
if (!grpc_mdelem_eq(b->idx.named.scheme->md, GRPC_MDELEM_SCHEME_HTTP) &&
!grpc_mdelem_eq(b->idx.named.scheme->md, GRPC_MDELEM_SCHEME_HTTPS) &&
!grpc_mdelem_eq(b->idx.named.scheme->md, GRPC_MDELEM_SCHEME_GRPC)) {
add_error(error_name, &error,
grpc_attach_md_to_error(
GRPC_ERROR_CREATE_FROM_STATIC_STRING("Bad header"),
b->idx.named.scheme->md));
}
grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.scheme);
} else {
add_error(
error_name, &error,
grpc_error_set_str(
GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing header"),
GRPC_ERROR_STR_KEY, grpc_slice_from_static_string(":scheme")));
}
if (b->idx.named.content_type != NULL) {
if (!grpc_mdelem_eq(b->idx.named.content_type->md,
GRPC_MDELEM_CONTENT_TYPE_APPLICATION_SLASH_GRPC)) {
if (grpc_slice_buf_start_eq(GRPC_MDVALUE(b->idx.named.content_type->md),
EXPECTED_CONTENT_TYPE,
EXPECTED_CONTENT_TYPE_LENGTH) &&
(GRPC_SLICE_START_PTR(GRPC_MDVALUE(
b->idx.named.content_type->md))[EXPECTED_CONTENT_TYPE_LENGTH] ==
'+' ||
GRPC_SLICE_START_PTR(GRPC_MDVALUE(
b->idx.named.content_type->md))[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. */
char *val = grpc_dump_slice(GRPC_MDVALUE(b->idx.named.content_type->md),
GPR_DUMP_ASCII);
gpr_log(GPR_INFO, "Unexpected content-type '%s'", val);
gpr_free(val);
}
}
grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.content_type);
}
if (b->idx.named.path == NULL) {
add_error(error_name, &error,
grpc_error_set_str(
GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing header"),
GRPC_ERROR_STR_KEY, grpc_slice_from_static_string(":path")));
} else if (*calld->recv_cacheable_request == true) {
/* We have a cacheable request made with GET verb. The path contains the
* query parameter which is base64 encoded request payload. */
const char k_query_separator = '?';
grpc_slice path_slice = GRPC_MDVALUE(b->idx.named.path->md);
uint8_t *path_ptr = (uint8_t *)GRPC_SLICE_START_PTR(path_slice);
size_t path_length = GRPC_SLICE_LENGTH(path_slice);
/* offset of the character '?' */
size_t offset = 0;
for (offset = 0; offset < path_length && *path_ptr != k_query_separator;
path_ptr++, offset++)
;
if (offset < path_length) {
grpc_slice query_slice =
grpc_slice_sub(path_slice, offset + 1, path_length);
/* substitute path metadata with just the path (not query) */
grpc_mdelem mdelem_path_without_query = grpc_mdelem_from_slices(
exec_ctx, GRPC_MDSTR_PATH, grpc_slice_sub(path_slice, 0, offset));
grpc_metadata_batch_substitute(exec_ctx, b, b->idx.named.path,
mdelem_path_without_query);
/* decode payload from query and add to the slice buffer to be returned */
const int k_url_safe = 1;
grpc_slice_buffer_add(
&calld->read_slice_buffer,
grpc_base64_decode(exec_ctx,
(const char *)GRPC_SLICE_START_PTR(query_slice),
k_url_safe));
grpc_slice_buffer_stream_init(&calld->read_stream,
&calld->read_slice_buffer, 0);
calld->seen_path_with_query = true;
grpc_slice_unref_internal(exec_ctx, query_slice);
} else {
gpr_log(GPR_ERROR, "GET request without QUERY");
}
}
if (b->idx.named.host != NULL && b->idx.named.authority == NULL) {
grpc_linked_mdelem *el = b->idx.named.host;
grpc_mdelem md = GRPC_MDELEM_REF(el->md);
grpc_metadata_batch_remove(exec_ctx, b, el);
add_error(
error_name, &error,
grpc_metadata_batch_add_head(
exec_ctx, b, el, grpc_mdelem_from_slices(
exec_ctx, GRPC_MDSTR_AUTHORITY,
grpc_slice_ref_internal(GRPC_MDVALUE(md)))));
GRPC_MDELEM_UNREF(exec_ctx, md);
}
if (b->idx.named.authority == NULL) {
add_error(
error_name, &error,
grpc_error_set_str(
GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing header"),
GRPC_ERROR_STR_KEY, grpc_slice_from_static_string(":authority")));
}
return error;
}
static void hs_on_recv(grpc_exec_ctx *exec_ctx, void *user_data,
grpc_error *err) {
grpc_call_element *elem = user_data;
call_data *calld = elem->call_data;
if (err == GRPC_ERROR_NONE) {
err = server_filter_incoming_metadata(exec_ctx, elem,
calld->recv_initial_metadata);
} else {
GRPC_ERROR_REF(err);
}
grpc_closure_run(exec_ctx, calld->on_done_recv, err);
}
static void hs_on_complete(grpc_exec_ctx *exec_ctx, void *user_data,
grpc_error *err) {
grpc_call_element *elem = user_data;
call_data *calld = elem->call_data;
/* Call recv_message_ready if we got the payload via the path field */
if (calld->seen_path_with_query && calld->recv_message_ready != NULL) {
*calld->pp_recv_message = calld->payload_bin_delivered
? NULL
: (grpc_byte_stream *)&calld->read_stream;
grpc_closure_run(exec_ctx, calld->recv_message_ready, GRPC_ERROR_REF(err));
calld->recv_message_ready = NULL;
calld->payload_bin_delivered = true;
}
grpc_closure_run(exec_ctx, calld->on_complete, GRPC_ERROR_REF(err));
}
static void hs_recv_message_ready(grpc_exec_ctx *exec_ctx, void *user_data,
grpc_error *err) {
grpc_call_element *elem = user_data;
call_data *calld = elem->call_data;
if (calld->seen_path_with_query) {
/* do nothing. This is probably a GET request, and payload will be returned
in hs_on_complete callback. */
} else {
grpc_closure_run(exec_ctx, calld->recv_message_ready, GRPC_ERROR_REF(err));
}
}
static void hs_mutate_op(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
grpc_transport_stream_op *op) {
/* grab pointers to our data from the call element */
call_data *calld = elem->call_data;
if (op->send_initial_metadata != NULL) {
grpc_error *error = GRPC_ERROR_NONE;
static const char *error_name = "Failed sending initial metadata";
add_error(error_name, &error, grpc_metadata_batch_add_head(
exec_ctx, op->send_initial_metadata,
&calld->status, GRPC_MDELEM_STATUS_200));
add_error(error_name, &error,
grpc_metadata_batch_add_tail(
exec_ctx, op->send_initial_metadata, &calld->content_type,
GRPC_MDELEM_CONTENT_TYPE_APPLICATION_SLASH_GRPC));
add_error(error_name, &error,
server_filter_outgoing_metadata(exec_ctx, elem,
op->send_initial_metadata));
if (error != GRPC_ERROR_NONE) {
grpc_transport_stream_op_finish_with_failure(exec_ctx, op, error);
return;
}
}
if (op->recv_initial_metadata) {
/* substitute our callback for the higher callback */
GPR_ASSERT(op->recv_idempotent_request != NULL);
GPR_ASSERT(op->recv_cacheable_request != NULL);
calld->recv_initial_metadata = op->recv_initial_metadata;
calld->recv_idempotent_request = op->recv_idempotent_request;
calld->recv_cacheable_request = op->recv_cacheable_request;
calld->on_done_recv = op->recv_initial_metadata_ready;
op->recv_initial_metadata_ready = &calld->hs_on_recv;
}
if (op->recv_message) {
calld->recv_message_ready = op->recv_message_ready;
calld->pp_recv_message = op->recv_message;
if (op->recv_message_ready) {
op->recv_message_ready = &calld->hs_recv_message_ready;
}
if (op->on_complete) {
calld->on_complete = op->on_complete;
op->on_complete = &calld->hs_on_complete;
}
}
if (op->send_trailing_metadata) {
grpc_error *error = server_filter_outgoing_metadata(
exec_ctx, elem, op->send_trailing_metadata);
if (error != GRPC_ERROR_NONE) {
grpc_transport_stream_op_finish_with_failure(exec_ctx, op, error);
return;
}
}
}
static void hs_start_transport_op(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem,
grpc_transport_stream_op *op) {
GRPC_CALL_LOG_OP(GPR_INFO, elem, op);
GPR_TIMER_BEGIN("hs_start_transport_op", 0);
hs_mutate_op(exec_ctx, elem, op);
grpc_call_next_op(exec_ctx, elem, op);
GPR_TIMER_END("hs_start_transport_op", 0);
}
/* Constructor for call_data */
static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem,
const grpc_call_element_args *args) {
/* grab pointers to our data from the call element */
call_data *calld = elem->call_data;
/* initialize members */
grpc_closure_init(&calld->hs_on_recv, hs_on_recv, elem,
grpc_schedule_on_exec_ctx);
grpc_closure_init(&calld->hs_on_complete, hs_on_complete, elem,
grpc_schedule_on_exec_ctx);
grpc_closure_init(&calld->hs_recv_message_ready, hs_recv_message_ready, elem,
grpc_schedule_on_exec_ctx);
grpc_slice_buffer_init(&calld->read_slice_buffer);
return GRPC_ERROR_NONE;
}
/* Destructor for call_data */
static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
const grpc_call_final_info *final_info,
grpc_closure *ignored) {
call_data *calld = elem->call_data;
grpc_slice_buffer_destroy_internal(exec_ctx, &calld->read_slice_buffer);
}
/* Constructor for channel_data */
static grpc_error *init_channel_elem(grpc_exec_ctx *exec_ctx,
grpc_channel_element *elem,
grpc_channel_element_args *args) {
GPR_ASSERT(!args->is_last);
return GRPC_ERROR_NONE;
}
/* Destructor for channel data */
static void destroy_channel_elem(grpc_exec_ctx *exec_ctx,
grpc_channel_element *elem) {}
const grpc_channel_filter grpc_http_server_filter = {
hs_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,
grpc_channel_next_get_info,
"http-server"};
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