| /* |
| * |
| * Copyright 2015 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 "src/core/lib/security/transport/security_handshaker.h" |
| |
| #include <stdbool.h> |
| #include <string.h> |
| |
| #include <grpc/slice_buffer.h> |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| |
| #include "src/core/lib/channel/channel_args.h" |
| #include "src/core/lib/channel/handshaker.h" |
| #include "src/core/lib/channel/handshaker_registry.h" |
| #include "src/core/lib/security/context/security_context.h" |
| #include "src/core/lib/security/transport/secure_endpoint.h" |
| #include "src/core/lib/security/transport/tsi_error.h" |
| #include "src/core/lib/slice/slice_internal.h" |
| |
| #define GRPC_INITIAL_HANDSHAKE_BUFFER_SIZE 256 |
| |
| typedef struct { |
| grpc_handshaker base; |
| |
| // State set at creation time. |
| tsi_handshaker *handshaker; |
| grpc_security_connector *connector; |
| |
| gpr_mu mu; |
| gpr_refcount refs; |
| |
| bool shutdown; |
| // Endpoint and read buffer to destroy after a shutdown. |
| grpc_endpoint *endpoint_to_destroy; |
| grpc_slice_buffer *read_buffer_to_destroy; |
| |
| // State saved while performing the handshake. |
| grpc_handshaker_args *args; |
| grpc_closure *on_handshake_done; |
| |
| unsigned char *handshake_buffer; |
| size_t handshake_buffer_size; |
| grpc_slice_buffer outgoing; |
| grpc_closure on_handshake_data_sent_to_peer; |
| grpc_closure on_handshake_data_received_from_peer; |
| grpc_closure on_peer_checked; |
| grpc_auth_context *auth_context; |
| tsi_handshaker_result *handshaker_result; |
| } security_handshaker; |
| |
| static void security_handshaker_unref(grpc_exec_ctx *exec_ctx, |
| security_handshaker *h) { |
| if (gpr_unref(&h->refs)) { |
| gpr_mu_destroy(&h->mu); |
| tsi_handshaker_destroy(h->handshaker); |
| tsi_handshaker_result_destroy(h->handshaker_result); |
| if (h->endpoint_to_destroy != NULL) { |
| grpc_endpoint_destroy(exec_ctx, h->endpoint_to_destroy); |
| } |
| if (h->read_buffer_to_destroy != NULL) { |
| grpc_slice_buffer_destroy_internal(exec_ctx, h->read_buffer_to_destroy); |
| gpr_free(h->read_buffer_to_destroy); |
| } |
| gpr_free(h->handshake_buffer); |
| grpc_slice_buffer_destroy_internal(exec_ctx, &h->outgoing); |
| GRPC_AUTH_CONTEXT_UNREF(h->auth_context, "handshake"); |
| GRPC_SECURITY_CONNECTOR_UNREF(exec_ctx, h->connector, "handshake"); |
| gpr_free(h); |
| } |
| } |
| |
| // Set args fields to NULL, saving the endpoint and read buffer for |
| // later destruction. |
| static void cleanup_args_for_failure_locked(grpc_exec_ctx *exec_ctx, |
| security_handshaker *h) { |
| h->endpoint_to_destroy = h->args->endpoint; |
| h->args->endpoint = NULL; |
| h->read_buffer_to_destroy = h->args->read_buffer; |
| h->args->read_buffer = NULL; |
| grpc_channel_args_destroy(exec_ctx, h->args->args); |
| h->args->args = NULL; |
| } |
| |
| // If the handshake failed or we're shutting down, clean up and invoke the |
| // callback with the error. |
| static void security_handshake_failed_locked(grpc_exec_ctx *exec_ctx, |
| security_handshaker *h, |
| grpc_error *error) { |
| if (error == GRPC_ERROR_NONE) { |
| // If we were shut down after the handshake succeeded but before an |
| // endpoint callback was invoked, we need to generate our own error. |
| error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Handshaker shutdown"); |
| } |
| const char *msg = grpc_error_string(error); |
| gpr_log(GPR_DEBUG, "Security handshake failed: %s", msg); |
| |
| if (!h->shutdown) { |
| // TODO(ctiller): It is currently necessary to shutdown endpoints |
| // before destroying them, even if we know that there are no |
| // pending read/write callbacks. This should be fixed, at which |
| // point this can be removed. |
| grpc_endpoint_shutdown(exec_ctx, h->args->endpoint, GRPC_ERROR_REF(error)); |
| // Not shutting down, so the write failed. Clean up before |
| // invoking the callback. |
| cleanup_args_for_failure_locked(exec_ctx, h); |
| // Set shutdown to true so that subsequent calls to |
| // security_handshaker_shutdown() do nothing. |
| h->shutdown = true; |
| } |
| // Invoke callback. |
| GRPC_CLOSURE_SCHED(exec_ctx, h->on_handshake_done, error); |
| } |
| |
| static void on_peer_checked(grpc_exec_ctx *exec_ctx, void *arg, |
| grpc_error *error) { |
| security_handshaker *h = arg; |
| gpr_mu_lock(&h->mu); |
| if (error != GRPC_ERROR_NONE || h->shutdown) { |
| security_handshake_failed_locked(exec_ctx, h, GRPC_ERROR_REF(error)); |
| goto done; |
| } |
| // Create frame protector. |
| tsi_frame_protector *protector; |
| tsi_result result = tsi_handshaker_result_create_frame_protector( |
| h->handshaker_result, NULL, &protector); |
| if (result != TSI_OK) { |
| error = grpc_set_tsi_error_result( |
| GRPC_ERROR_CREATE_FROM_STATIC_STRING("Frame protector creation failed"), |
| result); |
| security_handshake_failed_locked(exec_ctx, h, error); |
| goto done; |
| } |
| // Get unused bytes. |
| unsigned char *unused_bytes = NULL; |
| size_t unused_bytes_size = 0; |
| result = tsi_handshaker_result_get_unused_bytes( |
| h->handshaker_result, &unused_bytes, &unused_bytes_size); |
| // Create secure endpoint. |
| if (unused_bytes_size > 0) { |
| grpc_slice slice = |
| grpc_slice_from_copied_buffer((char *)unused_bytes, unused_bytes_size); |
| h->args->endpoint = |
| grpc_secure_endpoint_create(protector, h->args->endpoint, &slice, 1); |
| grpc_slice_unref_internal(exec_ctx, slice); |
| } else { |
| h->args->endpoint = |
| grpc_secure_endpoint_create(protector, h->args->endpoint, NULL, 0); |
| } |
| tsi_handshaker_result_destroy(h->handshaker_result); |
| h->handshaker_result = NULL; |
| // Clear out the read buffer before it gets passed to the transport. |
| grpc_slice_buffer_reset_and_unref_internal(exec_ctx, h->args->read_buffer); |
| // Add auth context to channel args. |
| grpc_arg auth_context_arg = grpc_auth_context_to_arg(h->auth_context); |
| grpc_channel_args *tmp_args = h->args->args; |
| h->args->args = |
| grpc_channel_args_copy_and_add(tmp_args, &auth_context_arg, 1); |
| grpc_channel_args_destroy(exec_ctx, tmp_args); |
| // Invoke callback. |
| GRPC_CLOSURE_SCHED(exec_ctx, h->on_handshake_done, GRPC_ERROR_NONE); |
| // Set shutdown to true so that subsequent calls to |
| // security_handshaker_shutdown() do nothing. |
| h->shutdown = true; |
| done: |
| gpr_mu_unlock(&h->mu); |
| security_handshaker_unref(exec_ctx, h); |
| } |
| |
| static grpc_error *check_peer_locked(grpc_exec_ctx *exec_ctx, |
| security_handshaker *h) { |
| tsi_peer peer; |
| tsi_result result = |
| tsi_handshaker_result_extract_peer(h->handshaker_result, &peer); |
| if (result != TSI_OK) { |
| return grpc_set_tsi_error_result( |
| GRPC_ERROR_CREATE_FROM_STATIC_STRING("Peer extraction failed"), result); |
| } |
| grpc_security_connector_check_peer(exec_ctx, h->connector, peer, |
| &h->auth_context, &h->on_peer_checked); |
| return GRPC_ERROR_NONE; |
| } |
| |
| static grpc_error *on_handshake_next_done_locked( |
| grpc_exec_ctx *exec_ctx, security_handshaker *h, tsi_result result, |
| const unsigned char *bytes_to_send, size_t bytes_to_send_size, |
| tsi_handshaker_result *handshaker_result) { |
| grpc_error *error = GRPC_ERROR_NONE; |
| // Read more if we need to. |
| if (result == TSI_INCOMPLETE_DATA) { |
| GPR_ASSERT(bytes_to_send_size == 0); |
| grpc_endpoint_read(exec_ctx, h->args->endpoint, h->args->read_buffer, |
| &h->on_handshake_data_received_from_peer); |
| return error; |
| } |
| if (result != TSI_OK) { |
| return grpc_set_tsi_error_result( |
| GRPC_ERROR_CREATE_FROM_STATIC_STRING("Handshake failed"), result); |
| } |
| // Update handshaker result. |
| if (handshaker_result != NULL) { |
| GPR_ASSERT(h->handshaker_result == NULL); |
| h->handshaker_result = handshaker_result; |
| } |
| if (bytes_to_send_size > 0) { |
| // Send data to peer, if needed. |
| grpc_slice to_send = grpc_slice_from_copied_buffer( |
| (const char *)bytes_to_send, bytes_to_send_size); |
| grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &h->outgoing); |
| grpc_slice_buffer_add(&h->outgoing, to_send); |
| grpc_endpoint_write(exec_ctx, h->args->endpoint, &h->outgoing, |
| &h->on_handshake_data_sent_to_peer); |
| } else if (handshaker_result == NULL) { |
| // There is nothing to send, but need to read from peer. |
| grpc_endpoint_read(exec_ctx, h->args->endpoint, h->args->read_buffer, |
| &h->on_handshake_data_received_from_peer); |
| } else { |
| // Handshake has finished, check peer and so on. |
| error = check_peer_locked(exec_ctx, h); |
| } |
| return error; |
| } |
| |
| static void on_handshake_next_done_grpc_wrapper( |
| tsi_result result, void *user_data, const unsigned char *bytes_to_send, |
| size_t bytes_to_send_size, tsi_handshaker_result *handshaker_result) { |
| security_handshaker *h = user_data; |
| // This callback will be invoked by TSI in a non-grpc thread, so it's |
| // safe to create our own exec_ctx here. |
| grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT; |
| gpr_mu_lock(&h->mu); |
| grpc_error *error = |
| on_handshake_next_done_locked(&exec_ctx, h, result, bytes_to_send, |
| bytes_to_send_size, handshaker_result); |
| if (error != GRPC_ERROR_NONE) { |
| security_handshake_failed_locked(&exec_ctx, h, error); |
| gpr_mu_unlock(&h->mu); |
| security_handshaker_unref(&exec_ctx, h); |
| } else { |
| gpr_mu_unlock(&h->mu); |
| } |
| grpc_exec_ctx_finish(&exec_ctx); |
| } |
| |
| static grpc_error *do_handshaker_next_locked( |
| grpc_exec_ctx *exec_ctx, security_handshaker *h, |
| const unsigned char *bytes_received, size_t bytes_received_size) { |
| // Invoke TSI handshaker. |
| unsigned char *bytes_to_send = NULL; |
| size_t bytes_to_send_size = 0; |
| tsi_handshaker_result *handshaker_result = NULL; |
| tsi_result result = tsi_handshaker_next( |
| h->handshaker, bytes_received, bytes_received_size, &bytes_to_send, |
| &bytes_to_send_size, &handshaker_result, |
| &on_handshake_next_done_grpc_wrapper, h); |
| if (result == TSI_ASYNC) { |
| // Handshaker operating asynchronously. Nothing else to do here; |
| // callback will be invoked in a TSI thread. |
| return GRPC_ERROR_NONE; |
| } |
| // Handshaker returned synchronously. Invoke callback directly in |
| // this thread with our existing exec_ctx. |
| return on_handshake_next_done_locked(exec_ctx, h, result, bytes_to_send, |
| bytes_to_send_size, handshaker_result); |
| } |
| |
| static void on_handshake_data_received_from_peer(grpc_exec_ctx *exec_ctx, |
| void *arg, grpc_error *error) { |
| security_handshaker *h = arg; |
| gpr_mu_lock(&h->mu); |
| if (error != GRPC_ERROR_NONE || h->shutdown) { |
| security_handshake_failed_locked( |
| exec_ctx, h, GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING( |
| "Handshake read failed", &error, 1)); |
| gpr_mu_unlock(&h->mu); |
| security_handshaker_unref(exec_ctx, h); |
| return; |
| } |
| // Copy all slices received. |
| size_t i; |
| size_t bytes_received_size = 0; |
| for (i = 0; i < h->args->read_buffer->count; i++) { |
| bytes_received_size += GRPC_SLICE_LENGTH(h->args->read_buffer->slices[i]); |
| } |
| if (bytes_received_size > h->handshake_buffer_size) { |
| h->handshake_buffer = gpr_realloc(h->handshake_buffer, bytes_received_size); |
| h->handshake_buffer_size = bytes_received_size; |
| } |
| size_t offset = 0; |
| for (i = 0; i < h->args->read_buffer->count; i++) { |
| size_t slice_size = GPR_SLICE_LENGTH(h->args->read_buffer->slices[i]); |
| memcpy(h->handshake_buffer + offset, |
| GRPC_SLICE_START_PTR(h->args->read_buffer->slices[i]), slice_size); |
| offset += slice_size; |
| } |
| // Call TSI handshaker. |
| error = do_handshaker_next_locked(exec_ctx, h, h->handshake_buffer, |
| bytes_received_size); |
| |
| if (error != GRPC_ERROR_NONE) { |
| security_handshake_failed_locked(exec_ctx, h, error); |
| gpr_mu_unlock(&h->mu); |
| security_handshaker_unref(exec_ctx, h); |
| } else { |
| gpr_mu_unlock(&h->mu); |
| } |
| } |
| |
| static void on_handshake_data_sent_to_peer(grpc_exec_ctx *exec_ctx, void *arg, |
| grpc_error *error) { |
| security_handshaker *h = arg; |
| gpr_mu_lock(&h->mu); |
| if (error != GRPC_ERROR_NONE || h->shutdown) { |
| security_handshake_failed_locked( |
| exec_ctx, h, GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING( |
| "Handshake write failed", &error, 1)); |
| gpr_mu_unlock(&h->mu); |
| security_handshaker_unref(exec_ctx, h); |
| return; |
| } |
| // We may be done. |
| if (h->handshaker_result == NULL) { |
| grpc_endpoint_read(exec_ctx, h->args->endpoint, h->args->read_buffer, |
| &h->on_handshake_data_received_from_peer); |
| } else { |
| error = check_peer_locked(exec_ctx, h); |
| if (error != GRPC_ERROR_NONE) { |
| security_handshake_failed_locked(exec_ctx, h, error); |
| gpr_mu_unlock(&h->mu); |
| security_handshaker_unref(exec_ctx, h); |
| return; |
| } |
| } |
| gpr_mu_unlock(&h->mu); |
| } |
| |
| // |
| // public handshaker API |
| // |
| |
| static void security_handshaker_destroy(grpc_exec_ctx *exec_ctx, |
| grpc_handshaker *handshaker) { |
| security_handshaker *h = (security_handshaker *)handshaker; |
| security_handshaker_unref(exec_ctx, h); |
| } |
| |
| static void security_handshaker_shutdown(grpc_exec_ctx *exec_ctx, |
| grpc_handshaker *handshaker, |
| grpc_error *why) { |
| security_handshaker *h = (security_handshaker *)handshaker; |
| gpr_mu_lock(&h->mu); |
| if (!h->shutdown) { |
| h->shutdown = true; |
| grpc_endpoint_shutdown(exec_ctx, h->args->endpoint, GRPC_ERROR_REF(why)); |
| cleanup_args_for_failure_locked(exec_ctx, h); |
| } |
| gpr_mu_unlock(&h->mu); |
| GRPC_ERROR_UNREF(why); |
| } |
| |
| static void security_handshaker_do_handshake(grpc_exec_ctx *exec_ctx, |
| grpc_handshaker *handshaker, |
| grpc_tcp_server_acceptor *acceptor, |
| grpc_closure *on_handshake_done, |
| grpc_handshaker_args *args) { |
| security_handshaker *h = (security_handshaker *)handshaker; |
| gpr_mu_lock(&h->mu); |
| h->args = args; |
| h->on_handshake_done = on_handshake_done; |
| gpr_ref(&h->refs); |
| grpc_error *error = do_handshaker_next_locked(exec_ctx, h, NULL, 0); |
| if (error != GRPC_ERROR_NONE) { |
| security_handshake_failed_locked(exec_ctx, h, error); |
| gpr_mu_unlock(&h->mu); |
| security_handshaker_unref(exec_ctx, h); |
| return; |
| } |
| gpr_mu_unlock(&h->mu); |
| } |
| |
| static const grpc_handshaker_vtable security_handshaker_vtable = { |
| security_handshaker_destroy, security_handshaker_shutdown, |
| security_handshaker_do_handshake}; |
| |
| static grpc_handshaker *security_handshaker_create( |
| grpc_exec_ctx *exec_ctx, tsi_handshaker *handshaker, |
| grpc_security_connector *connector) { |
| security_handshaker *h = gpr_zalloc(sizeof(security_handshaker)); |
| grpc_handshaker_init(&security_handshaker_vtable, &h->base); |
| h->handshaker = handshaker; |
| h->connector = GRPC_SECURITY_CONNECTOR_REF(connector, "handshake"); |
| gpr_mu_init(&h->mu); |
| gpr_ref_init(&h->refs, 1); |
| h->handshake_buffer_size = GRPC_INITIAL_HANDSHAKE_BUFFER_SIZE; |
| h->handshake_buffer = gpr_malloc(h->handshake_buffer_size); |
| GRPC_CLOSURE_INIT(&h->on_handshake_data_sent_to_peer, |
| on_handshake_data_sent_to_peer, h, |
| grpc_schedule_on_exec_ctx); |
| GRPC_CLOSURE_INIT(&h->on_handshake_data_received_from_peer, |
| on_handshake_data_received_from_peer, h, |
| grpc_schedule_on_exec_ctx); |
| GRPC_CLOSURE_INIT(&h->on_peer_checked, on_peer_checked, h, |
| grpc_schedule_on_exec_ctx); |
| grpc_slice_buffer_init(&h->outgoing); |
| return &h->base; |
| } |
| |
| // |
| // fail_handshaker |
| // |
| |
| static void fail_handshaker_destroy(grpc_exec_ctx *exec_ctx, |
| grpc_handshaker *handshaker) { |
| gpr_free(handshaker); |
| } |
| |
| static void fail_handshaker_shutdown(grpc_exec_ctx *exec_ctx, |
| grpc_handshaker *handshaker, |
| grpc_error *why) { |
| GRPC_ERROR_UNREF(why); |
| } |
| |
| static void fail_handshaker_do_handshake(grpc_exec_ctx *exec_ctx, |
| grpc_handshaker *handshaker, |
| grpc_tcp_server_acceptor *acceptor, |
| grpc_closure *on_handshake_done, |
| grpc_handshaker_args *args) { |
| GRPC_CLOSURE_SCHED(exec_ctx, on_handshake_done, |
| GRPC_ERROR_CREATE_FROM_STATIC_STRING( |
| "Failed to create security handshaker")); |
| } |
| |
| static const grpc_handshaker_vtable fail_handshaker_vtable = { |
| fail_handshaker_destroy, fail_handshaker_shutdown, |
| fail_handshaker_do_handshake}; |
| |
| static grpc_handshaker *fail_handshaker_create() { |
| grpc_handshaker *h = gpr_malloc(sizeof(*h)); |
| grpc_handshaker_init(&fail_handshaker_vtable, h); |
| return h; |
| } |
| |
| // |
| // handshaker factories |
| // |
| |
| static void client_handshaker_factory_add_handshakers( |
| grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *handshaker_factory, |
| const grpc_channel_args *args, grpc_handshake_manager *handshake_mgr) { |
| grpc_channel_security_connector *security_connector = |
| (grpc_channel_security_connector *)grpc_security_connector_find_in_args( |
| args); |
| grpc_channel_security_connector_add_handshakers(exec_ctx, security_connector, |
| handshake_mgr); |
| } |
| |
| static void server_handshaker_factory_add_handshakers( |
| grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *hf, |
| const grpc_channel_args *args, grpc_handshake_manager *handshake_mgr) { |
| grpc_server_security_connector *security_connector = |
| (grpc_server_security_connector *)grpc_security_connector_find_in_args( |
| args); |
| grpc_server_security_connector_add_handshakers(exec_ctx, security_connector, |
| handshake_mgr); |
| } |
| |
| static void handshaker_factory_destroy( |
| grpc_exec_ctx *exec_ctx, grpc_handshaker_factory *handshaker_factory) {} |
| |
| static const grpc_handshaker_factory_vtable client_handshaker_factory_vtable = { |
| client_handshaker_factory_add_handshakers, handshaker_factory_destroy}; |
| |
| static grpc_handshaker_factory client_handshaker_factory = { |
| &client_handshaker_factory_vtable}; |
| |
| static const grpc_handshaker_factory_vtable server_handshaker_factory_vtable = { |
| server_handshaker_factory_add_handshakers, handshaker_factory_destroy}; |
| |
| static grpc_handshaker_factory server_handshaker_factory = { |
| &server_handshaker_factory_vtable}; |
| |
| // |
| // exported functions |
| // |
| |
| grpc_handshaker *grpc_security_handshaker_create( |
| grpc_exec_ctx *exec_ctx, tsi_handshaker *handshaker, |
| grpc_security_connector *connector) { |
| // If no TSI handshaker was created, return a handshaker that always fails. |
| // Otherwise, return a real security handshaker. |
| if (handshaker == NULL) { |
| return fail_handshaker_create(); |
| } else { |
| return security_handshaker_create(exec_ctx, handshaker, connector); |
| } |
| } |
| |
| void grpc_security_register_handshaker_factories() { |
| grpc_handshaker_factory_register(false /* at_start */, HANDSHAKER_CLIENT, |
| &client_handshaker_factory); |
| grpc_handshaker_factory_register(false /* at_start */, HANDSHAKER_SERVER, |
| &server_handshaker_factory); |
| } |