FEATURE: Add memcached_sasl_authenticate_connection_ascii()

libmemcached/sasl.cc

@@ -43,6 +43,8 @@
 #include <sasl/sasl.h>
 #include <pthread.h>
 
+#define ASCII_SASL
+
 void memcached_set_sasl_callbacks(memcached_st *ptr,
                                   const sasl_callback_t *callbacks)
 {
@@ -120,7 +122,11 @@ static void sasl_startup_function(void)
 
 } // extern "C"
 
+#ifdef ASCII_SASL
+static memcached_return_t memcached_sasl_authenticate_connection_binary(memcached_server_st *server)
+#else
 memcached_return_t memcached_sasl_authenticate_connection(memcached_server_st *server)
+#endif
 {
   if (LIBMEMCACHED_WITH_SASL_SUPPORT == 0)
   {
@@ -270,6 +276,146 @@ memcached_return_t memcached_sasl_authenticate_connection(memcached_server_st *s
   return memcached_set_error(*server, rc, MEMCACHED_AT);
 }
 
+#ifdef ASCII_SASL
+static memcached_return_t memcached_sasl_authenticate_connection_ascii(memcached_server_st *server)
+{
+  char req_hdr[1024];
+  unsigned int hdrlen;
+  char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE + MEMCACHED_MAX_KEY];
+
+  hdrlen = snprintf(req_hdr, 1024, "sasl mech\r\n");
+  assert(hdrlen < 1024);
+
+  if (memcached_io_write(server, req_hdr, hdrlen, 1) != hdrlen) {
+    return MEMCACHED_WRITE_FAILURE;
+  }
+
+  memcached_server_response_increment(server);
+
+  memcached_return_t rc = memcached_response(server, buffer, sizeof(buffer), NULL);
+  assert(memcached_response(server, buffer, sizeof(buffer), NULL) == MEMCACHED_END);
+  if (memcached_failed(rc)) {
+    if (rc == MEMCACHED_PROTOCOL_ERROR) {
+      /* If the server doesn't support SASL it will return PROTOCOL_ERROR.
+       * This error may also be returned for other errors, but let's assume
+       * that the server don't support SASL and treat it as success and
+       * let the client fail with the next operation if the error was
+       * caused by another problem....
+       */
+      rc= MEMCACHED_SUCCESS;
+    }
+    return rc;
+  }
+
+  /* set ip addresses */
+  char laddr[NI_MAXHOST + NI_MAXSERV];
+  char raddr[NI_MAXHOST + NI_MAXSERV];
+
+  if (memcached_failed(rc = resolve_names(*server, laddr, sizeof(laddr), raddr, sizeof(raddr)))) {
+    return rc;
+  }
+
+  int pthread_error;
+  if ((pthread_error = pthread_once(&sasl_startup_once, sasl_startup_function)) != 0) {
+    return memcached_set_errno(*server, pthread_error, MEMCACHED_AT);
+  }
+
+  (void)pthread_mutex_lock(&sasl_startup_state_LOCK);
+  if (sasl_startup_state != SASL_OK) {
+    const char *sasl_error_msg= sasl_errstring(sasl_startup_state, NULL, NULL);
+    return memcached_set_error(*server, MEMCACHED_AUTH_PROBLEM, MEMCACHED_AT, 
+                               memcached_string_make_from_cstr(sasl_error_msg));
+  }
+  (void)pthread_mutex_unlock(&sasl_startup_state_LOCK);
+
+  sasl_conn_t *conn;
+  int ret;
+  if ((ret= sasl_client_new("memcached", server->hostname, laddr, raddr, server->root->sasl.callbacks, 0, &conn) ) != SASL_OK) {
+    const char *sasl_error_msg= sasl_errstring(ret, NULL, NULL);
+
+    sasl_dispose(&conn);
+
+    return memcached_set_error(*server, MEMCACHED_AUTH_PROBLEM, MEMCACHED_AT, 
+                               memcached_string_make_from_cstr(sasl_error_msg));
+  }
+
+  const char *data;
+  const char *chosenmech;
+  unsigned int len;
+  ret= sasl_client_start(conn, memcached_result_value(&server->root->result), NULL, &data, &len, &chosenmech);
+  if (ret != SASL_OK and ret != SASL_CONTINUE)
+  {
+    const char *sasl_error_msg= sasl_errstring(ret, NULL, NULL);
+
+    sasl_dispose(&conn);
+
+    return memcached_set_error(*server, MEMCACHED_AUTH_PROBLEM, MEMCACHED_AT, 
+                               memcached_string_make_from_cstr(sasl_error_msg));
+  }
+
+  hdrlen = snprintf(req_hdr, 1024, "sasl auth %s %u\r\n", chosenmech, len);
+
+  do {
+    /* send the packet */
+
+    struct libmemcached_io_vector_st vector[] = {
+      { hdrlen, req_hdr },
+      { len, data },
+      { 2, "\r\n" },
+    };
+
+    if (memcached_io_writev(server, vector, 3, true) == -1) {
+      rc = MEMCACHED_WRITE_FAILURE;
+      break;
+    }
+
+    memcached_server_response_increment(server);
+
+    rc = memcached_response(server, buffer, sizeof(buffer), NULL);
+    if (rc == MEMCACHED_SUCCESS) {
+      assert(memcached_response(server, buffer, sizeof(buffer), NULL) == MEMCACHED_END);
+    } else {
+      break;
+    }
+
+    ret = sasl_client_step(conn, memcached_result_value(&server->root->result),
+                           memcached_result_length(&server->root->result),
+                           NULL, &data, &len);
+    if (ret != SASL_OK && ret != SASL_CONTINUE) {
+      rc= MEMCACHED_AUTH_PROBLEM;
+      break;
+    }
+
+    hdrlen = snprintf(req_hdr, 1024, "sasl auth %u\r\n", len);
+  } while (true);
+
+  /* Release resources */
+  sasl_dispose(&conn);
+
+  return memcached_set_error(*server, rc, MEMCACHED_AT);
+}
+
+memcached_return_t memcached_sasl_authenticate_connection(memcached_server_st *server)
+{
+  if (LIBMEMCACHED_WITH_SASL_SUPPORT == 0)
+  {
+    return MEMCACHED_NOT_SUPPORTED;
+  }
+
+  if (server == NULL)
+  {
+    return MEMCACHED_INVALID_ARGUMENTS;
+  }
+
+  /* SANITY CHECK: SASL can only be used with the binary protocol */
+  if (server->root->flags.binary_protocol) {
+    return memcached_sasl_authenticate_connection_binary(server);
+  } else {
+    return memcached_sasl_authenticate_connection_ascii(server);
+  }
+}
+#endif
+
 static int get_username(void *context, int id, const char **result, unsigned int *len)
 {
   if (!context || !result || (id != SASL_CB_USER && id != SASL_CB_AUTHNAME))
@@ -313,11 +459,13 @@ memcached_return_t memcached_set_sasl_auth_data(memcached_st *ptr,
     return MEMCACHED_INVALID_ARGUMENTS;
   }
 
+#ifndef ASCII_SASL
   memcached_return_t ret;
   if (memcached_failed(ret= memcached_behavior_set(ptr, MEMCACHED_BEHAVIOR_BINARY_PROTOCOL, 1)))
   {
     return memcached_set_error(*ptr, ret, MEMCACHED_AT, memcached_literal_param("Unable change to binary protocol which is required for SASL."));
   }
+#endif
 
   memcached_destroy_sasl_auth_data(ptr);