1 /*
2 *
3 * Copyright 2020 gRPC authors.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 */
18
19 #include <grpc/support/port_platform.h>
20
21 #include "src/core/lib/iomgr/port.h"
22
23 #ifdef GRPC_POSIX_SOCKET_UTILS_COMMON
24
25 #include <netinet/in.h>
26 #include "src/core/lib/iomgr/socket_utils_posix.h"
27
28 #ifndef GRPC_SET_SOCKET_DUALSTACK_CUSTOM
29
30 /* This should be 0 in production, but it may be enabled for testing or
31 debugging purposes, to simulate an environment where IPv6 sockets can't
32 also speak IPv4. */
33 int grpc_forbid_dualstack_sockets_for_testing = 0;
34
grpc_set_socket_dualstack(int fd)35 int grpc_set_socket_dualstack(int fd) {
36 if (!grpc_forbid_dualstack_sockets_for_testing) {
37 const int off = 0;
38 return 0 == setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &off, sizeof(off));
39 } else {
40 /* Force an IPv6-only socket, for testing purposes. */
41 const int on = 1;
42 setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on));
43 return 0;
44 }
45 }
46 #endif // GRPC_SET_SOCKET_DUALSTACK_CUSTOM
47 #endif // GRPC_POSIX_SOCKET_UTILS_COMMON
48