| /* |
| * |
| * 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 <grpc/support/port_platform.h> |
| |
| #include "src/core/lib/security/credentials/credentials.h" |
| |
| #include <string.h> |
| |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| #include <grpc/support/sync.h> |
| |
| #include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h" |
| #include "src/core/lib/channel/channel_args.h" |
| #include "src/core/lib/gpr/env.h" |
| #include "src/core/lib/gpr/string.h" |
| #include "src/core/lib/gprpp/ref_counted_ptr.h" |
| #include "src/core/lib/http/httpcli.h" |
| #include "src/core/lib/http/parser.h" |
| #include "src/core/lib/iomgr/load_file.h" |
| #include "src/core/lib/iomgr/polling_entity.h" |
| #include "src/core/lib/security/credentials/alts/alts_credentials.h" |
| #include "src/core/lib/security/credentials/alts/check_gcp_environment.h" |
| #include "src/core/lib/security/credentials/google_default/google_default_credentials.h" |
| #include "src/core/lib/security/credentials/jwt/jwt_credentials.h" |
| #include "src/core/lib/security/credentials/oauth2/oauth2_credentials.h" |
| #include "src/core/lib/slice/slice_internal.h" |
| #include "src/core/lib/slice/slice_string_helpers.h" |
| #include "src/core/lib/surface/api_trace.h" |
| |
| /* -- Constants. -- */ |
| |
| #define GRPC_COMPUTE_ENGINE_DETECTION_HOST "metadata.google.internal" |
| |
| /* -- Default credentials. -- */ |
| |
| /* A sticky bit that will be set only if the result of metadata server detection |
| * is positive. We do not set the bit if the result is negative. Because it |
| * means the detection is done via network test that is unreliable and the |
| * unreliable result should not be referred by successive calls. */ |
| static int g_metadata_server_available = 0; |
| static int g_is_on_gce = 0; |
| static gpr_mu g_state_mu; |
| /* Protect a metadata_server_detector instance that can be modified by more than |
| * one gRPC threads */ |
| static gpr_mu* g_polling_mu; |
| static gpr_once g_once = GPR_ONCE_INIT; |
| static grpc_core::internal::grpc_gce_tenancy_checker g_gce_tenancy_checker = |
| grpc_alts_is_running_on_gcp; |
| |
| static void init_default_credentials(void) { gpr_mu_init(&g_state_mu); } |
| |
| typedef struct { |
| grpc_polling_entity pollent; |
| int is_done; |
| int success; |
| grpc_http_response response; |
| } metadata_server_detector; |
| |
| grpc_core::RefCountedPtr<grpc_channel_security_connector> |
| grpc_google_default_channel_credentials::create_security_connector( |
| grpc_core::RefCountedPtr<grpc_call_credentials> call_creds, |
| const char* target, const grpc_channel_args* args, |
| grpc_channel_args** new_args) { |
| bool is_grpclb_load_balancer = grpc_channel_arg_get_bool( |
| grpc_channel_args_find(args, GRPC_ARG_ADDRESS_IS_GRPCLB_LOAD_BALANCER), |
| false); |
| bool is_backend_from_grpclb_load_balancer = grpc_channel_arg_get_bool( |
| grpc_channel_args_find( |
| args, GRPC_ARG_ADDRESS_IS_BACKEND_FROM_GRPCLB_LOAD_BALANCER), |
| false); |
| bool use_alts = |
| is_grpclb_load_balancer || is_backend_from_grpclb_load_balancer; |
| /* Return failure if ALTS is selected but not running on GCE. */ |
| if (use_alts && !g_is_on_gce) { |
| gpr_log(GPR_ERROR, "ALTS is selected, but not running on GCE."); |
| return nullptr; |
| } |
| |
| grpc_core::RefCountedPtr<grpc_channel_security_connector> sc = |
| use_alts ? alts_creds_->create_security_connector(call_creds, target, |
| args, new_args) |
| : ssl_creds_->create_security_connector(call_creds, target, args, |
| new_args); |
| /* grpclb-specific channel args are removed from the channel args set |
| * to ensure backends and fallback adresses will have the same set of channel |
| * args. By doing that, it guarantees the connections to backends will not be |
| * torn down and re-connected when switching in and out of fallback mode. |
| */ |
| if (use_alts) { |
| static const char* args_to_remove[] = { |
| GRPC_ARG_ADDRESS_IS_GRPCLB_LOAD_BALANCER, |
| GRPC_ARG_ADDRESS_IS_BACKEND_FROM_GRPCLB_LOAD_BALANCER, |
| }; |
| *new_args = grpc_channel_args_copy_and_add_and_remove( |
| args, args_to_remove, GPR_ARRAY_SIZE(args_to_remove), nullptr, 0); |
| } |
| return sc; |
| } |
| |
| static void on_metadata_server_detection_http_response(void* user_data, |
| grpc_error* error) { |
| metadata_server_detector* detector = |
| static_cast<metadata_server_detector*>(user_data); |
| if (error == GRPC_ERROR_NONE && detector->response.status == 200 && |
| detector->response.hdr_count > 0) { |
| /* Internet providers can return a generic response to all requests, so |
| it is necessary to check that metadata header is present also. */ |
| size_t i; |
| for (i = 0; i < detector->response.hdr_count; i++) { |
| grpc_http_header* header = &detector->response.hdrs[i]; |
| if (strcmp(header->key, "Metadata-Flavor") == 0 && |
| strcmp(header->value, "Google") == 0) { |
| detector->success = 1; |
| break; |
| } |
| } |
| } |
| gpr_mu_lock(g_polling_mu); |
| detector->is_done = 1; |
| GRPC_LOG_IF_ERROR( |
| "Pollset kick", |
| grpc_pollset_kick(grpc_polling_entity_pollset(&detector->pollent), |
| nullptr)); |
| gpr_mu_unlock(g_polling_mu); |
| } |
| |
| static void destroy_pollset(void* p, grpc_error* e) { |
| grpc_pollset_destroy(static_cast<grpc_pollset*>(p)); |
| } |
| |
| static int is_metadata_server_reachable() { |
| metadata_server_detector detector; |
| grpc_httpcli_request request; |
| grpc_httpcli_context context; |
| grpc_closure destroy_closure; |
| /* The http call is local. If it takes more than one sec, it is for sure not |
| on compute engine. */ |
| grpc_millis max_detection_delay = GPR_MS_PER_SEC; |
| grpc_pollset* pollset = |
| static_cast<grpc_pollset*>(gpr_zalloc(grpc_pollset_size())); |
| grpc_pollset_init(pollset, &g_polling_mu); |
| detector.pollent = grpc_polling_entity_create_from_pollset(pollset); |
| detector.is_done = 0; |
| detector.success = 0; |
| memset(&detector.response, 0, sizeof(detector.response)); |
| memset(&request, 0, sizeof(grpc_httpcli_request)); |
| request.host = (char*)GRPC_COMPUTE_ENGINE_DETECTION_HOST; |
| request.http.path = (char*)"/"; |
| grpc_httpcli_context_init(&context); |
| grpc_resource_quota* resource_quota = |
| grpc_resource_quota_create("google_default_credentials"); |
| grpc_httpcli_get( |
| &context, &detector.pollent, resource_quota, &request, |
| grpc_core::ExecCtx::Get()->Now() + max_detection_delay, |
| GRPC_CLOSURE_CREATE(on_metadata_server_detection_http_response, &detector, |
| grpc_schedule_on_exec_ctx), |
| &detector.response); |
| grpc_resource_quota_unref_internal(resource_quota); |
| grpc_core::ExecCtx::Get()->Flush(); |
| /* Block until we get the response. This is not ideal but this should only be |
| called once for the lifetime of the process by the default credentials. */ |
| gpr_mu_lock(g_polling_mu); |
| while (!detector.is_done) { |
| grpc_pollset_worker* worker = nullptr; |
| if (!GRPC_LOG_IF_ERROR( |
| "pollset_work", |
| grpc_pollset_work(grpc_polling_entity_pollset(&detector.pollent), |
| &worker, GRPC_MILLIS_INF_FUTURE))) { |
| detector.is_done = 1; |
| detector.success = 0; |
| } |
| } |
| gpr_mu_unlock(g_polling_mu); |
| grpc_httpcli_context_destroy(&context); |
| GRPC_CLOSURE_INIT(&destroy_closure, destroy_pollset, |
| grpc_polling_entity_pollset(&detector.pollent), |
| grpc_schedule_on_exec_ctx); |
| grpc_pollset_shutdown(grpc_polling_entity_pollset(&detector.pollent), |
| &destroy_closure); |
| g_polling_mu = nullptr; |
| grpc_core::ExecCtx::Get()->Flush(); |
| gpr_free(grpc_polling_entity_pollset(&detector.pollent)); |
| grpc_http_response_destroy(&detector.response); |
| return detector.success; |
| } |
| |
| /* Takes ownership of creds_path if not NULL. */ |
| static grpc_error* create_default_creds_from_path( |
| char* creds_path, grpc_core::RefCountedPtr<grpc_call_credentials>* creds) { |
| grpc_json* json = nullptr; |
| grpc_auth_json_key key; |
| grpc_auth_refresh_token token; |
| grpc_core::RefCountedPtr<grpc_call_credentials> result; |
| grpc_slice creds_data = grpc_empty_slice(); |
| grpc_error* error = GRPC_ERROR_NONE; |
| if (creds_path == nullptr) { |
| error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("creds_path unset"); |
| goto end; |
| } |
| error = grpc_load_file(creds_path, 0, &creds_data); |
| if (error != GRPC_ERROR_NONE) { |
| goto end; |
| } |
| json = grpc_json_parse_string_with_len( |
| reinterpret_cast<char*> GRPC_SLICE_START_PTR(creds_data), |
| GRPC_SLICE_LENGTH(creds_data)); |
| if (json == nullptr) { |
| error = grpc_error_set_str( |
| GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to parse JSON"), |
| GRPC_ERROR_STR_RAW_BYTES, grpc_slice_ref_internal(creds_data)); |
| goto end; |
| } |
| |
| /* First, try an auth json key. */ |
| key = grpc_auth_json_key_create_from_json(json); |
| if (grpc_auth_json_key_is_valid(&key)) { |
| result = |
| grpc_service_account_jwt_access_credentials_create_from_auth_json_key( |
| key, grpc_max_auth_token_lifetime()); |
| if (result == nullptr) { |
| error = GRPC_ERROR_CREATE_FROM_STATIC_STRING( |
| "grpc_service_account_jwt_access_credentials_create_from_auth_json_" |
| "key failed"); |
| } |
| goto end; |
| } |
| |
| /* Then try a refresh token if the auth json key was invalid. */ |
| token = grpc_auth_refresh_token_create_from_json(json); |
| if (grpc_auth_refresh_token_is_valid(&token)) { |
| result = |
| grpc_refresh_token_credentials_create_from_auth_refresh_token(token); |
| if (result == nullptr) { |
| error = GRPC_ERROR_CREATE_FROM_STATIC_STRING( |
| "grpc_refresh_token_credentials_create_from_auth_refresh_token " |
| "failed"); |
| } |
| goto end; |
| } |
| |
| end: |
| GPR_ASSERT((result == nullptr) + (error == GRPC_ERROR_NONE) == 1); |
| if (creds_path != nullptr) gpr_free(creds_path); |
| grpc_slice_unref_internal(creds_data); |
| if (json != nullptr) grpc_json_destroy(json); |
| *creds = result; |
| return error; |
| } |
| |
| grpc_channel_credentials* grpc_google_default_credentials_create() { |
| grpc_channel_credentials* result = nullptr; |
| grpc_core::RefCountedPtr<grpc_call_credentials> call_creds; |
| grpc_error* error = GRPC_ERROR_CREATE_FROM_STATIC_STRING( |
| "Failed to create Google credentials"); |
| grpc_error* err; |
| grpc_core::ExecCtx exec_ctx; |
| |
| GRPC_API_TRACE("grpc_google_default_credentials_create(void)", 0, ()); |
| |
| gpr_once_init(&g_once, init_default_credentials); |
| |
| /* First, try the environment variable. */ |
| err = create_default_creds_from_path( |
| gpr_getenv(GRPC_GOOGLE_CREDENTIALS_ENV_VAR), &call_creds); |
| if (err == GRPC_ERROR_NONE) goto end; |
| error = grpc_error_add_child(error, err); |
| |
| /* Then the well-known file. */ |
| err = create_default_creds_from_path( |
| grpc_get_well_known_google_credentials_file_path(), &call_creds); |
| if (err == GRPC_ERROR_NONE) goto end; |
| error = grpc_error_add_child(error, err); |
| |
| gpr_mu_lock(&g_state_mu); |
| |
| /* Try a platform-provided hint for GCE. */ |
| if (!g_metadata_server_available) { |
| g_is_on_gce = g_gce_tenancy_checker(); |
| g_metadata_server_available = g_is_on_gce; |
| } |
| /* TODO: Add a platform-provided hint for GAE. */ |
| |
| /* Do a network test for metadata server. */ |
| if (!g_metadata_server_available) { |
| g_metadata_server_available = is_metadata_server_reachable(); |
| } |
| gpr_mu_unlock(&g_state_mu); |
| |
| if (g_metadata_server_available) { |
| call_creds = grpc_core::RefCountedPtr<grpc_call_credentials>( |
| grpc_google_compute_engine_credentials_create(nullptr)); |
| if (call_creds == nullptr) { |
| error = grpc_error_add_child( |
| error, GRPC_ERROR_CREATE_FROM_STATIC_STRING( |
| "Failed to get credentials from network")); |
| } |
| } |
| |
| end: |
| if (call_creds != nullptr) { |
| /* Create google default credentials. */ |
| grpc_channel_credentials* ssl_creds = |
| grpc_ssl_credentials_create(nullptr, nullptr, nullptr, nullptr); |
| GPR_ASSERT(ssl_creds != nullptr); |
| grpc_alts_credentials_options* options = |
| grpc_alts_credentials_client_options_create(); |
| grpc_channel_credentials* alts_creds = |
| grpc_alts_credentials_create(options); |
| grpc_alts_credentials_options_destroy(options); |
| auto creds = |
| grpc_core::MakeRefCounted<grpc_google_default_channel_credentials>( |
| alts_creds != nullptr ? alts_creds->Ref() : nullptr, |
| ssl_creds != nullptr ? ssl_creds->Ref() : nullptr); |
| if (ssl_creds) ssl_creds->Unref(); |
| if (alts_creds) alts_creds->Unref(); |
| result = grpc_composite_channel_credentials_create( |
| creds.get(), call_creds.get(), nullptr); |
| GPR_ASSERT(result != nullptr); |
| } else { |
| gpr_log(GPR_ERROR, "Could not create google default credentials: %s", |
| grpc_error_string(error)); |
| } |
| GRPC_ERROR_UNREF(error); |
| return result; |
| } |
| |
| namespace grpc_core { |
| namespace internal { |
| |
| void set_gce_tenancy_checker_for_testing(grpc_gce_tenancy_checker checker) { |
| g_gce_tenancy_checker = checker; |
| } |
| |
| void grpc_flush_cached_google_default_credentials(void) { |
| grpc_core::ExecCtx exec_ctx; |
| gpr_once_init(&g_once, init_default_credentials); |
| gpr_mu_lock(&g_state_mu); |
| g_metadata_server_available = 0; |
| gpr_mu_unlock(&g_state_mu); |
| } |
| |
| } // namespace internal |
| } // namespace grpc_core |
| |
| /* -- Well known credentials path. -- */ |
| |
| static grpc_well_known_credentials_path_getter creds_path_getter = nullptr; |
| |
| char* grpc_get_well_known_google_credentials_file_path(void) { |
| if (creds_path_getter != nullptr) return creds_path_getter(); |
| return grpc_get_well_known_google_credentials_file_path_impl(); |
| } |
| |
| void grpc_override_well_known_credentials_path_getter( |
| grpc_well_known_credentials_path_getter getter) { |
| creds_path_getter = getter; |
| } |