Merge github.com:grpc/grpc into you-complete-me

1 files changed, 330 insertions, 0 deletions

diff --git a/src/core/security/client_auth_filter.c b/src/core/security/client_auth_filter.c
new file mode 100644
index 0000000000..b2bce1fd32
--- /dev/null
+++ b/src/core/security/client_auth_filter.c
@@ -0,0 +1,330 @@
+/*
+ *
+ * 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_filters.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/security_connector.h"
+#include "src/core/security/credentials.h"
+#include "src/core/surface/call.h"
+
+#define MAX_CREDENTIALS_METADATA_COUNT 4
+
+/* We can have a per-call credentials. */
+typedef struct {
+  grpc_credentials *creds;
+  grpc_mdstr *host;
+  grpc_mdstr *method;
+  grpc_transport_op op;
+  size_t op_md_idx;
+  int sent_initial_metadata;
+  grpc_linked_mdelem md_links[MAX_CREDENTIALS_METADATA_COUNT];
+} call_data;
+
+/* We can have a per-channel credentials. */
+typedef struct {
+  grpc_channel_security_connector *security_connector;
+  grpc_mdctx *md_ctx;
+  grpc_mdstr *authority_string;
+  grpc_mdstr *path_string;
+  grpc_mdstr *error_msg_key;
+  grpc_mdstr *status_key;
+} channel_data;
+
+static void bubble_up_error(grpc_call_element *elem, const char *error_msg) {
+  call_data *calld = elem->call_data;
+  channel_data *chand = elem->channel_data;
+  grpc_transport_op_add_cancellation(
+      &calld->op, GRPC_STATUS_UNAUTHENTICATED,
+      grpc_mdstr_from_string(chand->md_ctx, error_msg));
+  grpc_call_next_op(elem, &calld->op);
+}
+
+static void on_credentials_metadata(void *user_data,
+                                    grpc_credentials_md *md_elems,
+                                    size_t num_md,
+                                    grpc_credentials_status status) {
+  grpc_call_element *elem = (grpc_call_element *)user_data;
+  call_data *calld = elem->call_data;
+  channel_data *chand = elem->channel_data;
+  grpc_transport_op *op = &calld->op;
+  grpc_metadata_batch *mdb;
+  size_t i;
+  if (status != GRPC_CREDENTIALS_OK) {
+    bubble_up_error(elem, "Credentials failed to get metadata.");
+    return;
+  }
+  GPR_ASSERT(num_md <= MAX_CREDENTIALS_METADATA_COUNT);
+  GPR_ASSERT(op->send_ops && op->send_ops->nops > calld->op_md_idx &&
+             op->send_ops->ops[calld->op_md_idx].type == GRPC_OP_METADATA);
+  mdb = &op->send_ops->ops[calld->op_md_idx].data.metadata;
+  for (i = 0; i < num_md; i++) {
+    grpc_metadata_batch_add_tail(
+        mdb, &calld->md_links[i],
+        grpc_mdelem_from_slices(chand->md_ctx, gpr_slice_ref(md_elems[i].key),
+                                gpr_slice_ref(md_elems[i].value)));
+  }
+  grpc_call_next_op(elem, op);
+}
+
+static char *build_service_url(const char *url_scheme, call_data *calld) {
+  char *service_url;
+  char *service = gpr_strdup(grpc_mdstr_as_c_string(calld->method));
+  char *last_slash = strrchr(service, '/');
+  if (last_slash == NULL) {
+    gpr_log(GPR_ERROR, "No '/' found in fully qualified method name");
+    service[0] = '\0';
+  } else if (last_slash == service) {
+    /* No service part in fully qualified method name: will just be "/". */
+    service[1] = '\0';
+  } else {
+    *last_slash = '\0';
+  }
+  if (url_scheme == NULL) url_scheme = "";
+  gpr_asprintf(&service_url, "%s://%s%s", url_scheme,
+               grpc_mdstr_as_c_string(calld->host), service);
+  gpr_free(service);
+  return service_url;
+}
+
+static void send_security_metadata(grpc_call_element *elem,
+                                   grpc_transport_op *op) {
+  call_data *calld = elem->call_data;
+  channel_data *chand = elem->channel_data;
+  grpc_client_security_context *ctx =
+      (grpc_client_security_context *)op->context[GRPC_CONTEXT_SECURITY].value;
+  char *service_url = NULL;
+  grpc_credentials *channel_creds =
+      chand->security_connector->request_metadata_creds;
+  int channel_creds_has_md =
+      (channel_creds != NULL) &&
+      grpc_credentials_has_request_metadata(channel_creds);
+  int call_creds_has_md = (ctx != NULL) && (ctx->creds != NULL) &&
+                          grpc_credentials_has_request_metadata(ctx->creds);
+
+  if (!channel_creds_has_md && !call_creds_has_md) {
+    /* Skip sending metadata altogether. */
+    grpc_call_next_op(elem, op);
+    return;
+  }
+
+  if (channel_creds_has_md && call_creds_has_md) {
+    calld->creds = grpc_composite_credentials_create(channel_creds, ctx->creds);
+    if (calld->creds == NULL) {
+      bubble_up_error(elem,
+                      "Incompatible credentials set on channel and call.");
+      return;
+    }
+  } else {
+    calld->creds =
+        grpc_credentials_ref(call_creds_has_md ? ctx->creds : channel_creds);
+  }
+
+  service_url =
+      build_service_url(chand->security_connector->base.url_scheme, calld);
+  calld->op = *op; /* Copy op (originates from the caller's stack). */
+  grpc_credentials_get_request_metadata(calld->creds, service_url,
+                                        on_credentials_metadata, elem);
+  gpr_free(service_url);
+}
+
+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));
+    bubble_up_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 auth_start_transport_op(grpc_call_element *elem,
+                                    grpc_transport_op *op) {
+  /* grab pointers to our data from the call element */
+  call_data *calld = elem->call_data;
+  channel_data *chand = elem->channel_data;
+  grpc_linked_mdelem *l;
+  size_t i;
+
+  /* TODO(jboeuf): write the call auth context. */
+
+  if (op->send_ops && !calld->sent_initial_metadata) {
+    size_t nops = op->send_ops->nops;
+    grpc_stream_op *ops = op->send_ops->ops;
+    for (i = 0; i < nops; i++) {
+      grpc_stream_op *sop = &ops[i];
+      if (sop->type != GRPC_OP_METADATA) continue;
+      calld->op_md_idx = i;
+      calld->sent_initial_metadata = 1;
+      for (l = sop->data.metadata.list.head; l != NULL; l = l->next) {
+        grpc_mdelem *md = l->md;
+        /* Pointer comparison is OK for md_elems created from the same context.
+         */
+        if (md->key == chand->authority_string) {
+          if (calld->host != NULL) grpc_mdstr_unref(calld->host);
+          calld->host = grpc_mdstr_ref(md->value);
+        } else if (md->key == chand->path_string) {
+          if (calld->method != NULL) grpc_mdstr_unref(calld->method);
+          calld->method = grpc_mdstr_ref(md->value);
+        }
+      }
+      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_connector_check_call_host(
+            chand->security_connector, 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);
+            bubble_up_error(elem, error_msg);
+            gpr_free(error_msg);
+          }
+          return; /* early exit */
+        }
+      }
+      send_security_metadata(elem, op);
+      return; /* early exit */
+    }
+  }
+
+  /* pass control up or down the stack */
+  grpc_call_next_op(elem, op);
+}
+
+/* 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,
+                           grpc_transport_op *initial_op) {
+  call_data *calld = elem->call_data;
+  calld->creds = NULL;
+  calld->host = NULL;
+  calld->method = NULL;
+  calld->sent_initial_metadata = 0;
+
+  GPR_ASSERT(!initial_op || !initial_op->send_ops);
+}
+
+/* Destructor for call_data */
+static void destroy_call_elem(grpc_call_element *elem) {
+  call_data *calld = elem->call_data;
+  grpc_credentials_unref(calld->creds);
+  if (calld->host != NULL) {
+    grpc_mdstr_unref(calld->host);
+  }
+  if (calld->method != NULL) {
+    grpc_mdstr_unref(calld->method);
+  }
+}
+
+/* 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_connector *sc = grpc_find_security_connector_in_args(args);
+  /* grab pointers to our data from the channel element */
+  channel_data *chand = 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(sc != NULL);
+
+  /* initialize members */
+  GPR_ASSERT(sc->is_client_side);
+  chand->security_connector =
+      (grpc_channel_security_connector *)grpc_security_connector_ref(sc);
+  chand->md_ctx = metadata_context;
+  chand->authority_string =
+      grpc_mdstr_from_string(chand->md_ctx, ":authority");
+  chand->path_string = grpc_mdstr_from_string(chand->md_ctx, ":path");
+  chand->error_msg_key =
+      grpc_mdstr_from_string(chand->md_ctx, "grpc-message");
+  chand->status_key =
+      grpc_mdstr_from_string(chand->md_ctx, "grpc-status");
+}
+
+/* Destructor for channel data */
+static void destroy_channel_elem(grpc_channel_element *elem) {
+  /* grab pointers to our data from the channel element */
+  channel_data *chand = elem->channel_data;
+  grpc_channel_security_connector *ctx = chand->security_connector;
+  if (ctx != NULL) grpc_security_connector_unref(&ctx->base);
+  if (chand->authority_string != NULL) {
+    grpc_mdstr_unref(chand->authority_string);
+  }
+  if (chand->error_msg_key != NULL) {
+    grpc_mdstr_unref(chand->error_msg_key);
+  }
+  if (chand->status_key != NULL) {
+    grpc_mdstr_unref(chand->status_key);
+  }
+  if (chand->path_string != NULL) {
+    grpc_mdstr_unref(chand->path_string);
+  }
+}
+
+const grpc_channel_filter grpc_client_auth_filter = {
+    auth_start_transport_op, channel_op, sizeof(call_data), init_call_elem,
+    destroy_call_elem, sizeof(channel_data), init_channel_elem,
+    destroy_channel_elem, "client-auth"};