diff options
author | 2017-07-21 15:42:00 -0700 | |
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committer | 2017-07-21 15:42:00 -0700 | |
commit | e0778b2c1817f3b7aff5af4b1b15493d4a8a207d (patch) | |
tree | ac0249dc00b2aa50a2a7a0eeb31469d02a333735 /src/core/lib/security/transport/client_auth_filter.c | |
parent | 8321cadeb031cfa7f142479b40fc13e52216790c (diff) |
Add cancellation to asynchronous security APIs.
Diffstat (limited to 'src/core/lib/security/transport/client_auth_filter.c')
-rw-r--r-- | src/core/lib/security/transport/client_auth_filter.c | 186 |
1 files changed, 147 insertions, 39 deletions
diff --git a/src/core/lib/security/transport/client_auth_filter.c b/src/core/lib/security/transport/client_auth_filter.c index 50a51b31cd..531a88434f 100644 --- a/src/core/lib/security/transport/client_auth_filter.c +++ b/src/core/lib/security/transport/client_auth_filter.c @@ -51,8 +51,15 @@ typedef struct { grpc_polling_entity *pollent; gpr_atm security_context_set; gpr_mu security_context_mu; + grpc_credentials_mdelem_array md_array; grpc_linked_mdelem md_links[MAX_CREDENTIALS_METADATA_COUNT]; grpc_auth_metadata_context auth_md_context; + grpc_closure closure; + // Either 0 (no cancellation and no async operation in flight), + // a grpc_closure* (if the lowest bit is 0), + // or a grpc_error* (if the lowest bit is 1). + gpr_atm cancellation_state; + grpc_closure cancel_closure; } call_data; /* We can have a per-channel credentials. */ @@ -61,6 +68,43 @@ typedef struct { grpc_auth_context *auth_context; } channel_data; +static void decode_cancel_state(gpr_atm cancel_state, grpc_closure **func, + grpc_error **error) { + // If the lowest bit is 1, the value is a grpc_error*. + // Otherwise, if non-zdero, the value is a grpc_closure*. + if (cancel_state & 1) { + *error = (grpc_error *)(cancel_state & ~(gpr_atm)1); + } else if (cancel_state != 0) { + *func = (grpc_closure *)cancel_state; + } +} + +static gpr_atm encode_cancel_state_error(grpc_error *error) { + // Set the lowest bit to 1 to indicate that it's an error. + return (gpr_atm)1 | (gpr_atm)error; +} + +// Returns an error if the call has been cancelled. Otherwise, sets the +// cancellation function to be called upon cancellation. +static grpc_error *set_cancel_func(grpc_call_element *elem, + grpc_iomgr_cb_func func) { + call_data *calld = (call_data *)elem->call_data; + // Decode original state. + gpr_atm original_state = gpr_atm_acq_load(&calld->cancellation_state); + grpc_error *original_error = GRPC_ERROR_NONE; + grpc_closure *original_func = NULL; + decode_cancel_state(original_state, &original_func, &original_error); + // If error is set, return it. + if (original_error != GRPC_ERROR_NONE) return GRPC_ERROR_REF(original_error); + // Otherwise, store func. + GRPC_CLOSURE_INIT(&calld->cancel_closure, func, elem, + grpc_schedule_on_exec_ctx); + GPR_ASSERT(((gpr_atm)&calld->cancel_closure & (gpr_atm)1) == 0); + gpr_atm_rel_store(&calld->cancellation_state, + (gpr_atm)&calld->cancel_closure); + return GRPC_ERROR_NONE; +} + static void reset_auth_metadata_context( grpc_auth_metadata_context *auth_md_context) { if (auth_md_context->service_url != NULL) { @@ -86,41 +130,29 @@ static void add_error(grpc_error **combined, grpc_error *error) { *combined = grpc_error_add_child(*combined, error); } -static void on_credentials_metadata(grpc_exec_ctx *exec_ctx, void *user_data, - grpc_credentials_md *md_elems, - size_t num_md, - grpc_credentials_status status, - const char *error_details) { - grpc_transport_stream_op_batch *batch = - (grpc_transport_stream_op_batch *)user_data; +static void on_credentials_metadata(grpc_exec_ctx *exec_ctx, void *arg, + grpc_error *input_error) { + grpc_transport_stream_op_batch *batch = (grpc_transport_stream_op_batch *)arg; grpc_call_element *elem = batch->handler_private.extra_arg; call_data *calld = elem->call_data; reset_auth_metadata_context(&calld->auth_md_context); - grpc_error *error = GRPC_ERROR_NONE; - if (status != GRPC_CREDENTIALS_OK) { - error = grpc_error_set_int( - GRPC_ERROR_CREATE_FROM_COPIED_STRING( - error_details != NULL && strlen(error_details) > 0 - ? error_details - : "Credentials failed to get metadata."), - GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAUTHENTICATED); - } else { - GPR_ASSERT(num_md <= MAX_CREDENTIALS_METADATA_COUNT); + grpc_error *error = GRPC_ERROR_REF(input_error); + if (error == GRPC_ERROR_NONE) { + GPR_ASSERT(calld->md_array.size <= MAX_CREDENTIALS_METADATA_COUNT); GPR_ASSERT(batch->send_initial_metadata); grpc_metadata_batch *mdb = batch->payload->send_initial_metadata.send_initial_metadata; - for (size_t i = 0; i < num_md; i++) { - add_error(&error, - grpc_metadata_batch_add_tail( - exec_ctx, mdb, &calld->md_links[i], - grpc_mdelem_from_slices( - exec_ctx, grpc_slice_ref_internal(md_elems[i].key), - grpc_slice_ref_internal(md_elems[i].value)))); + for (size_t i = 0; i < calld->md_array.size; ++i) { + add_error(&error, grpc_metadata_batch_add_tail( + exec_ctx, mdb, &calld->md_links[i], + GRPC_MDELEM_REF(calld->md_array.md[i]))); } } if (error == GRPC_ERROR_NONE) { grpc_call_next_op(exec_ctx, elem, batch); } else { + error = grpc_error_set_int(error, GRPC_ERROR_INT_GRPC_STATUS, + GRPC_STATUS_UNAUTHENTICATED); grpc_transport_stream_op_batch_finish_with_failure(exec_ctx, batch, error); } } @@ -155,6 +187,14 @@ void build_auth_metadata_context(grpc_security_connector *sc, gpr_free(host); } +static void cancel_get_request_metadata(grpc_exec_ctx *exec_ctx, void *arg, + grpc_error *error) { + grpc_call_element *elem = (grpc_call_element *)arg; + call_data *calld = (call_data *)elem->call_data; + grpc_call_credentials_cancel_get_request_metadata( + exec_ctx, calld->creds, &calld->md_array, GRPC_ERROR_REF(error)); +} + static void send_security_metadata(grpc_exec_ctx *exec_ctx, grpc_call_element *elem, grpc_transport_stream_op_batch *batch) { @@ -193,20 +233,33 @@ static void send_security_metadata(grpc_exec_ctx *exec_ctx, build_auth_metadata_context(&chand->security_connector->base, chand->auth_context, calld); + + grpc_error *cancel_error = set_cancel_func(elem, cancel_get_request_metadata); + if (cancel_error != GRPC_ERROR_NONE) { + grpc_transport_stream_op_batch_finish_with_failure(exec_ctx, batch, + cancel_error); + return; + } GPR_ASSERT(calld->pollent != NULL); - grpc_call_credentials_get_request_metadata( - exec_ctx, calld->creds, calld->pollent, calld->auth_md_context, - on_credentials_metadata, batch); + GRPC_CLOSURE_INIT(&calld->closure, on_credentials_metadata, batch, + grpc_schedule_on_exec_ctx); + grpc_error *error = GRPC_ERROR_NONE; + if (grpc_call_credentials_get_request_metadata( + exec_ctx, calld->creds, calld->pollent, calld->auth_md_context, + &calld->md_array, &calld->closure, &error)) { + // Synchronous return; invoke on_credentials_metadata() directly. + on_credentials_metadata(exec_ctx, batch, error); + GRPC_ERROR_UNREF(error); + } } -static void on_host_checked(grpc_exec_ctx *exec_ctx, void *user_data, - grpc_security_status status) { - grpc_transport_stream_op_batch *batch = - (grpc_transport_stream_op_batch *)user_data; +static void on_host_checked(grpc_exec_ctx *exec_ctx, void *arg, + grpc_error *error) { + grpc_transport_stream_op_batch *batch = (grpc_transport_stream_op_batch *)arg; grpc_call_element *elem = batch->handler_private.extra_arg; call_data *calld = elem->call_data; - if (status == GRPC_SECURITY_OK) { + if (error == GRPC_ERROR_NONE) { send_security_metadata(exec_ctx, elem, batch); } else { char *error_msg; @@ -223,6 +276,16 @@ static void on_host_checked(grpc_exec_ctx *exec_ctx, void *user_data, } } +static void cancel_check_call_host(grpc_exec_ctx *exec_ctx, void *arg, + grpc_error *error) { + grpc_call_element *elem = (grpc_call_element *)arg; + call_data *calld = (call_data *)elem->call_data; + channel_data *chand = (channel_data *)elem->channel_data; + grpc_channel_security_connector_cancel_check_call_host( + exec_ctx, chand->security_connector, &calld->closure, + GRPC_ERROR_REF(error)); +} + static void auth_start_transport_stream_op_batch( grpc_exec_ctx *exec_ctx, grpc_call_element *elem, grpc_transport_stream_op_batch *batch) { @@ -232,7 +295,32 @@ static void auth_start_transport_stream_op_batch( call_data *calld = elem->call_data; channel_data *chand = elem->channel_data; - if (!batch->cancel_stream) { + if (batch->cancel_stream) { + while (true) { + // Decode the original cancellation state. + gpr_atm original_state = gpr_atm_acq_load(&calld->cancellation_state); + grpc_error *cancel_error = GRPC_ERROR_NONE; + grpc_closure *func = NULL; + decode_cancel_state(original_state, &func, &cancel_error); + // If we had already set a cancellation error, there's nothing + // more to do. + if (cancel_error != GRPC_ERROR_NONE) break; + // If there's a cancel func, call it. + // Note that even if the cancel func has been changed by some + // other thread between when we decoded it and now, it will just + // be a no-op. + cancel_error = GRPC_ERROR_REF(batch->payload->cancel_stream.cancel_error); + if (func != NULL) { + GRPC_CLOSURE_SCHED(exec_ctx, func, GRPC_ERROR_REF(cancel_error)); + } + // Encode the new error into cancellation state. + if (gpr_atm_full_cas(&calld->cancellation_state, original_state, + encode_cancel_state_error(cancel_error))) { + break; // Success. + } + // The cas failed, so try again. + } + } else { /* double checked lock over security context to ensure it's set once */ if (gpr_atm_acq_load(&calld->security_context_set) == 0) { gpr_mu_lock(&calld->security_context_mu); @@ -277,12 +365,26 @@ static void auth_start_transport_stream_op_batch( } } if (calld->have_host) { - char *call_host = grpc_slice_to_c_string(calld->host); - batch->handler_private.extra_arg = elem; - grpc_channel_security_connector_check_call_host( - exec_ctx, chand->security_connector, call_host, chand->auth_context, - on_host_checked, batch); - gpr_free(call_host); + grpc_error *cancel_error = set_cancel_func(elem, cancel_check_call_host); + if (cancel_error != GRPC_ERROR_NONE) { + grpc_transport_stream_op_batch_finish_with_failure(exec_ctx, batch, + cancel_error); + } else { + char *call_host = grpc_slice_to_c_string(calld->host); + batch->handler_private.extra_arg = elem; + grpc_error *error = GRPC_ERROR_NONE; + if (grpc_channel_security_connector_check_call_host( + exec_ctx, chand->security_connector, call_host, + chand->auth_context, + GRPC_CLOSURE_INIT(&calld->closure, on_host_checked, batch, + grpc_schedule_on_exec_ctx), + &error)) { + // Synchronous return; invoke on_host_checked() directly. + on_host_checked(exec_ctx, batch, error); + GRPC_ERROR_UNREF(error); + } + gpr_free(call_host); + } GPR_TIMER_END("auth_start_transport_stream_op_batch", 0); return; /* early exit */ } @@ -315,6 +417,7 @@ 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_credentials_mdelem_array_destroy(exec_ctx, &calld->md_array); grpc_call_credentials_unref(exec_ctx, calld->creds); if (calld->have_host) { grpc_slice_unref_internal(exec_ctx, calld->host); @@ -324,6 +427,11 @@ static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem, } reset_auth_metadata_context(&calld->auth_md_context); gpr_mu_destroy(&calld->security_context_mu); + gpr_atm cancel_state = gpr_atm_acq_load(&calld->cancellation_state); + grpc_error *cancel_error = GRPC_ERROR_NONE; + grpc_closure *cancel_func = NULL; + decode_cancel_state(cancel_state, &cancel_func, &cancel_error); + GRPC_ERROR_UNREF(cancel_error); } /* Constructor for channel_data */ |