| /* |
| * |
| * 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/security/auth.h" |
| |
| #include <string.h> |
| |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| |
| #include "src/core/support/string.h" |
| #include "src/core/channel/channel_stack.h" |
| #include "src/core/security/security_context.h" |
| #include "src/core/security/credentials.h" |
| #include "src/core/surface/call.h" |
| |
| /* We can have a per-call credentials. */ |
| typedef struct { |
| grpc_credentials *creds; |
| grpc_mdstr *host; |
| grpc_call_op op; |
| } call_data; |
| |
| /* We can have a per-channel credentials. */ |
| typedef struct { |
| grpc_channel_security_context *security_context; |
| grpc_mdctx *md_ctx; |
| grpc_mdstr *authority_string; |
| grpc_mdstr *error_msg_key; |
| } channel_data; |
| |
| static void do_nothing(void *ignored, grpc_op_error error) {} |
| |
| static void bubbleup_error(grpc_call_element *elem, const char *error_msg) { |
| grpc_call_op finish_op; |
| channel_data *channeld = elem->channel_data; |
| |
| gpr_log(GPR_ERROR, "%s", error_msg); |
| finish_op.type = GRPC_RECV_METADATA; |
| finish_op.dir = GRPC_CALL_UP; |
| finish_op.flags = 0; |
| finish_op.data.metadata = grpc_mdelem_from_metadata_strings( |
| channeld->md_ctx, channeld->error_msg_key, |
| grpc_mdstr_from_string(channeld->md_ctx, error_msg)); |
| finish_op.done_cb = do_nothing; |
| finish_op.user_data = NULL; |
| grpc_call_next_op(elem, &finish_op); |
| grpc_call_element_send_cancel(elem); |
| } |
| |
| static void on_credentials_metadata(void *user_data, grpc_mdelem **md_elems, |
| size_t num_md, |
| grpc_credentials_status status) { |
| grpc_call_element *elem = (grpc_call_element *)user_data; |
| size_t i; |
| for (i = 0; i < num_md; i++) { |
| grpc_call_element_send_metadata(elem, grpc_mdelem_ref(md_elems[i])); |
| } |
| grpc_call_next_op(elem, &((call_data *)elem->call_data)->op); |
| } |
| |
| static void send_security_metadata(grpc_call_element *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_credentials *channel_creds = |
| channeld->security_context->request_metadata_creds; |
| /* TODO(jboeuf): |
| Decide on the policy in this case: |
| - populate both channel and call? |
| - the call takes precedence over the channel? |
| - leave this decision up to the channel credentials? */ |
| if (calld->creds != NULL) { |
| gpr_log(GPR_ERROR, "Ignoring per call credentials for now."); |
| } |
| if (channel_creds != NULL && |
| grpc_credentials_has_request_metadata(channel_creds)) { |
| calld->op = *op; /* Copy op (originates from the caller's stack). */ |
| grpc_credentials_get_request_metadata(channel_creds, |
| on_credentials_metadata, elem); |
| } else { |
| grpc_call_next_op(elem, op); |
| } |
| } |
| |
| static void on_host_checked(void *user_data, grpc_security_status status) { |
| grpc_call_element *elem = (grpc_call_element *)user_data; |
| call_data *calld = elem->call_data; |
| |
| if (status == GRPC_SECURITY_OK) { |
| send_security_metadata(elem, &calld->op); |
| } else { |
| char *error_msg; |
| gpr_asprintf(&error_msg, "Invalid host %s set in :authority metadata.", |
| grpc_mdstr_as_c_string(calld->host)); |
| bubbleup_error(elem, error_msg); |
| gpr_free(error_msg); |
| } |
| } |
| |
| /* 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; |
| |
| switch (op->type) { |
| case GRPC_SEND_METADATA: |
| /* Pointer comparison is OK for md_elems created from the same context. */ |
| if (op->data.metadata->key == channeld->authority_string) { |
| if (calld->host != NULL) grpc_mdstr_unref(calld->host); |
| calld->host = grpc_mdstr_ref(op->data.metadata->value); |
| } |
| grpc_call_next_op(elem, op); |
| break; |
| |
| case GRPC_SEND_START: |
| if (calld->host != NULL) { |
| grpc_security_status status; |
| const char *call_host = grpc_mdstr_as_c_string(calld->host); |
| calld->op = *op; /* Copy op (originates from the caller's stack). */ |
| status = grpc_channel_security_context_check_call_host( |
| channeld->security_context, call_host, on_host_checked, elem); |
| if (status != GRPC_SECURITY_OK) { |
| if (status == GRPC_SECURITY_ERROR) { |
| char *error_msg; |
| gpr_asprintf(&error_msg, |
| "Invalid host %s set in :authority metadata.", |
| call_host); |
| bubbleup_error(elem, error_msg); |
| gpr_free(error_msg); |
| } |
| break; |
| } |
| } |
| send_security_metadata(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) { |
| grpc_channel_next_op(elem, op); |
| } |
| |
| /* Constructor for call_data */ |
| static void init_call_elem(grpc_call_element *elem, |
| const void *server_transport_data) { |
| /* TODO(jboeuf): |
| Find a way to pass-in the credentials from the caller here. */ |
| call_data *calld = elem->call_data; |
| calld->creds = NULL; |
| calld->host = NULL; |
| } |
| |
| /* Destructor for call_data */ |
| static void destroy_call_elem(grpc_call_element *elem) { |
| call_data *calld = elem->call_data; |
| if (calld->creds != NULL) { |
| grpc_credentials_unref(calld->creds); |
| } |
| if (calld->host != NULL) { |
| grpc_mdstr_unref(calld->host); |
| } |
| } |
| |
| /* Constructor for channel_data */ |
| static void init_channel_elem(grpc_channel_element *elem, |
| const grpc_channel_args *args, |
| grpc_mdctx *metadata_context, int is_first, |
| int is_last) { |
| grpc_security_context *ctx = grpc_find_security_context_in_args(args); |
| /* 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); |
| GPR_ASSERT(ctx != NULL); |
| |
| /* initialize members */ |
| GPR_ASSERT(ctx->is_client_side); |
| channeld->security_context = |
| (grpc_channel_security_context *)grpc_security_context_ref(ctx); |
| channeld->md_ctx = metadata_context; |
| channeld->authority_string = |
| grpc_mdstr_from_string(channeld->md_ctx, ":authority"); |
| channeld->error_msg_key = |
| grpc_mdstr_from_string(channeld->md_ctx, "grpc-message"); |
| } |
| |
| /* Destructor for channel data */ |
| static void destroy_channel_elem(grpc_channel_element *elem) { |
| /* grab pointers to our data from the channel element */ |
| channel_data *channeld = elem->channel_data; |
| grpc_channel_security_context *ctx = channeld->security_context; |
| if (ctx != NULL) grpc_security_context_unref(&ctx->base); |
| if (channeld->authority_string != NULL) { |
| grpc_mdstr_unref(channeld->authority_string); |
| } |
| if (channeld->error_msg_key != NULL) { |
| grpc_mdstr_unref(channeld->error_msg_key); |
| } |
| } |
| |
| const grpc_channel_filter grpc_client_auth_filter = { |
| call_op, channel_op, sizeof(call_data), |
| init_call_elem, destroy_call_elem, sizeof(channel_data), |
| init_channel_elem, destroy_channel_elem, "auth"}; |