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
27 #include "src/core/lib/iomgr/socket_utils_posix.h"
28
29 #ifndef GRPC_SET_SOCKET_DUALSTACK_CUSTOM
30
31 // This should be 0 in production, but it may be enabled for testing or
32 // debugging purposes, to simulate an environment where IPv6 sockets can't
33 // also speak IPv4.
34 int grpc_forbid_dualstack_sockets_for_testing = 0;
35
grpc_set_socket_dualstack(int fd)36 int grpc_set_socket_dualstack(int fd) {
37 if (!grpc_forbid_dualstack_sockets_for_testing) {
38 const int off = 0;
39 return 0 == setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &off, sizeof(off));
40 } else {
41 // Force an IPv6-only socket, for testing purposes.
42 const int on = 1;
43 setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on));
44 return 0;
45 }
46 }
47 #endif // GRPC_SET_SOCKET_DUALSTACK_CUSTOM
48 #endif // GRPC_POSIX_SOCKET_UTILS_COMMON
49