Merge pull request #1506 from jboeuf/call_creds

Adding support for per call credentials in core.

5 files changed, 208 insertions, 60 deletions

diff --git a/src/core/security/auth.c b/src/core/security/auth.c
index 2322c12aa5..faf12d8f14 100644
--- a/src/core/security/auth.c
+++ b/src/core/security/auth.c
@@ -40,6 +40,7 @@
 
 #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"
@@ -67,6 +68,15 @@ typedef struct {
   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_mdelem **md_elems,
                                     size_t num_md,
                                     grpc_credentials_status status) {
@@ -75,6 +85,10 @@ static void on_credentials_metadata(void *user_data, grpc_mdelem **md_elems,
   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);
@@ -108,37 +122,48 @@ static char *build_service_url(const char *url_scheme, call_data *calld) {
 
 static void send_security_metadata(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 *channeld = elem->channel_data;
-
+  channel_data *chand = elem->channel_data;
+  grpc_client_security_context *ctx =
+      (grpc_client_security_context *)op->context[GRPC_CONTEXT_SECURITY];
+  char *service_url = NULL;
   grpc_credentials *channel_creds =
-      channeld->security_connector->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.");
+      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 != NULL &&
-      grpc_credentials_has_request_metadata(channel_creds)) {
-    char *service_url =
-        build_service_url(channeld->security_connector->base.url_scheme, calld);
-    calld->op = *op; /* Copy op (originates from the caller's stack). */
-    grpc_credentials_get_request_metadata(channel_creds, service_url,
-                                          on_credentials_metadata, elem);
-    gpr_free(service_url);
+
+  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 {
-    grpc_call_next_op(elem, op);
+    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;
-  channel_data *chand = elem->channel_data;
 
   if (status == GRPC_SECURITY_OK) {
     send_security_metadata(elem, &calld->op);
@@ -146,11 +171,8 @@ static void on_host_checked(void *user_data, grpc_security_status status) {
     char *error_msg;
     gpr_asprintf(&error_msg, "Invalid host %s set in :authority metadata.",
                  grpc_mdstr_as_c_string(calld->host));
-    grpc_transport_op_add_cancellation(
-        &calld->op, GRPC_STATUS_UNAUTHENTICATED,
-        grpc_mdstr_from_string(chand->md_ctx, error_msg));
+    bubble_up_error(elem, error_msg);
     gpr_free(error_msg);
-    grpc_call_next_op(elem, &calld->op);
   }
 }
 
@@ -163,7 +185,7 @@ 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 *channeld = elem->channel_data;
+  channel_data *chand = elem->channel_data;
   grpc_linked_mdelem *l;
   size_t i;
 
@@ -179,10 +201,10 @@ static void auth_start_transport_op(grpc_call_element *elem,
         grpc_mdelem *md = l->md;
         /* Pointer comparison is OK for md_elems created from the same context.
          */
-        if (md->key == channeld->authority_string) {
+        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 == channeld->path_string) {
+        } else if (md->key == chand->path_string) {
           if (calld->method != NULL) grpc_mdstr_unref(calld->method);
           calld->method = grpc_mdstr_ref(md->value);
         }
@@ -192,18 +214,15 @@ static void auth_start_transport_op(grpc_call_element *elem,
         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(
-            channeld->security_connector, call_host, on_host_checked, elem);
+            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);
-            grpc_transport_op_add_cancellation(
-                &calld->op, GRPC_STATUS_UNAUTHENTICATED,
-                grpc_mdstr_from_string(channeld->md_ctx, error_msg));
+            bubble_up_error(elem, error_msg);
             gpr_free(error_msg);
-            grpc_call_next_op(elem, &calld->op);
           }
           return; /* early exit */
         }
@@ -228,8 +247,6 @@ static void channel_op(grpc_channel_element *elem,
 static void init_call_elem(grpc_call_element *elem,
                            const void *server_transport_data,
                            grpc_transport_op *initial_op) {
-  /* 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;
@@ -242,9 +259,7 @@ static void init_call_elem(grpc_call_element *elem,
 /* 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);
-  }
+  grpc_credentials_unref(calld->creds);
   if (calld->host != NULL) {
     grpc_mdstr_unref(calld->host);
   }
@@ -260,7 +275,7 @@ static void init_channel_elem(grpc_channel_element *elem,
                               int is_last) {
   grpc_security_connector *ctx = grpc_find_security_connector_in_args(args);
   /* grab pointers to our data from the channel element */
-  channel_data *channeld = elem->channel_data;
+  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
@@ -271,35 +286,35 @@ static void init_channel_elem(grpc_channel_element *elem,
 
   /* initialize members */
   GPR_ASSERT(ctx->is_client_side);
-  channeld->security_connector =
+  chand->security_connector =
       (grpc_channel_security_connector *)grpc_security_connector_ref(ctx);
-  channeld->md_ctx = metadata_context;
-  channeld->authority_string =
-      grpc_mdstr_from_string(channeld->md_ctx, ":authority");
-  channeld->path_string = grpc_mdstr_from_string(channeld->md_ctx, ":path");
-  channeld->error_msg_key =
-      grpc_mdstr_from_string(channeld->md_ctx, "grpc-message");
-  channeld->status_key =
-      grpc_mdstr_from_string(channeld->md_ctx, "grpc-status");
+  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 *channeld = elem->channel_data;
-  grpc_channel_security_connector *ctx = channeld->security_connector;
+  channel_data *chand = elem->channel_data;
+  grpc_channel_security_connector *ctx = chand->security_connector;
   if (ctx != NULL) grpc_security_connector_unref(&ctx->base);
-  if (channeld->authority_string != NULL) {
-    grpc_mdstr_unref(channeld->authority_string);
+  if (chand->authority_string != NULL) {
+    grpc_mdstr_unref(chand->authority_string);
   }
-  if (channeld->error_msg_key != NULL) {
-    grpc_mdstr_unref(channeld->error_msg_key);
+  if (chand->error_msg_key != NULL) {
+    grpc_mdstr_unref(chand->error_msg_key);
   }
-  if (channeld->status_key != NULL) {
-    grpc_mdstr_unref(channeld->status_key);
+  if (chand->status_key != NULL) {
+    grpc_mdstr_unref(chand->status_key);
   }
-  if (channeld->path_string != NULL) {
-    grpc_mdstr_unref(channeld->path_string);
+  if (chand->path_string != NULL) {
+    grpc_mdstr_unref(chand->path_string);
   }
 }
 
diff --git a/src/core/security/security_context.c b/src/core/security/security_context.c
new file mode 100644
index 0000000000..b90dc5097a
--- /dev/null
+++ b/src/core/security/security_context.c
@@ -0,0 +1,79 @@
+/*
+ *
+ * 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 <string.h>
+
+#include "src/core/security/security_context.h"
+#include "src/core/surface/call.h"
+
+#include <grpc/grpc_security.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+
+grpc_call_error grpc_call_set_credentials(grpc_call *call,
+                                          grpc_credentials *creds) {
+  grpc_client_security_context *ctx = NULL;
+  if (!grpc_call_is_client(call)) {
+    gpr_log(GPR_ERROR, "Method is client-side only.");
+    return GRPC_CALL_ERROR_NOT_ON_SERVER;
+  }
+  if (creds != NULL && !grpc_credentials_has_request_metadata_only(creds)) {
+    gpr_log(GPR_ERROR, "Incompatible credentials to set on a call.");
+    return GRPC_CALL_ERROR;
+  }
+  ctx = (grpc_client_security_context *)grpc_call_context_get(
+      call, GRPC_CONTEXT_SECURITY);
+  if (ctx == NULL) {
+    ctx = grpc_client_security_context_create();
+    ctx->creds = grpc_credentials_ref(creds);
+    grpc_call_context_set(call, GRPC_CONTEXT_SECURITY, ctx,
+                          grpc_client_security_context_destroy);
+  } else {
+    grpc_credentials_unref(ctx->creds);
+    ctx->creds = grpc_credentials_ref(creds);
+  }
+  return GRPC_CALL_OK;
+}
+
+grpc_client_security_context *grpc_client_security_context_create(void) {
+  grpc_client_security_context *ctx =
+      gpr_malloc(sizeof(grpc_client_security_context));
+  memset(ctx, 0, sizeof(grpc_client_security_context));
+  return ctx;
+}
+
+void grpc_client_security_context_destroy(void *ctx) {
+  grpc_client_security_context *c = (grpc_client_security_context *)ctx;
+  grpc_credentials_unref(c->creds);
+  gpr_free(ctx);
+}
diff --git a/src/core/security/security_context.h b/src/core/security/security_context.h
new file mode 100644
index 0000000000..561633b452
--- /dev/null
+++ b/src/core/security/security_context.h
@@ -0,0 +1,48 @@
+/*
+ *
+ * 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.
+ *
+ */
+
+#ifndef GRPC_INTERNAL_CORE_SECURITY_SECURITY_CONTEXT_H
+#define GRPC_INTERNAL_CORE_SECURITY_SECURITY_CONTEXT_H
+
+#include "src/core/security/credentials.h"
+
+/* Security context attached to a client-side call. */
+typedef struct {
+  grpc_credentials *creds;
+} grpc_client_security_context;
+
+grpc_client_security_context *grpc_client_security_context_create(void);
+void grpc_client_security_context_destroy(void *ctx);
+
+#endif  /* GRPC_INTERNAL_CORE_SECURITY_SECURITY_CONTEXT_H */
+
diff --git a/src/core/surface/call.c b/src/core/surface/call.c
index aa58fa13ed..e117f270df 100644
--- a/src/core/surface/call.c
+++ b/src/core/surface/call.c
@@ -1302,3 +1302,5 @@ void grpc_call_context_set(grpc_call *call, grpc_context_index elem, void *value
 void *grpc_call_context_get(grpc_call *call, grpc_context_index elem) {
   return call->context[elem];
 }
+
+gpr_uint8 grpc_call_is_client(grpc_call *call) { return call->is_client; }
diff --git a/src/core/surface/call.h b/src/core/surface/call.h
index 18a77babac..02378b6e8e 100644
--- a/src/core/surface/call.h
+++ b/src/core/surface/call.h
@@ -98,12 +98,14 @@ grpc_completion_queue *grpc_call_get_completion_queue(grpc_call *call);
 void grpc_call_internal_ref(grpc_call *call, const char *reason);
 void grpc_call_internal_unref(grpc_call *call, const char *reason, int allow_immediate_deletion);
 #define GRPC_CALL_INTERNAL_REF(call, reason) grpc_call_internal_ref(call, reason)
-#define GRPC_CALL_INTERNAL_UNREF(call, reason, allow_immediate_deletion) grpc_call_internal_unref(call, reason, allow_immediate_deletion)
+#define GRPC_CALL_INTERNAL_UNREF(call, reason, allow_immediate_deletion) \
+  grpc_call_internal_unref(call, reason, allow_immediate_deletion)
 #else
 void grpc_call_internal_ref(grpc_call *call);
 void grpc_call_internal_unref(grpc_call *call, int allow_immediate_deletion);
 #define GRPC_CALL_INTERNAL_REF(call, reason) grpc_call_internal_ref(call)
-#define GRPC_CALL_INTERNAL_UNREF(call, reason, allow_immediate_deletion) grpc_call_internal_unref(call, allow_immediate_deletion)
+#define GRPC_CALL_INTERNAL_UNREF(call, reason, allow_immediate_deletion) \
+  grpc_call_internal_unref(call, allow_immediate_deletion)
 #endif
 
 grpc_call_error grpc_call_start_ioreq_and_call_back(
@@ -131,4 +133,6 @@ void *grpc_call_context_get(grpc_call *call, grpc_context_index elem);
 #define GRPC_CALL_LOG_BATCH(sev, call, ops, nops, tag) \
   if (grpc_trace_batch) grpc_call_log_batch(sev, call, ops, nops, tag)
 
+gpr_uint8 grpc_call_is_client(grpc_call *call);
+
 #endif /* GRPC_INTERNAL_CORE_SURFACE_CALL_H */