1 // Copyright (C) 2020 The Android Open Source Project
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include <dlfcn.h>
16 #include <netinet/in.h>
17 #include <sys/socket.h>
18 #include <sys/types.h>
19
20 static int (*real_bind)(int sockfd, const sockaddr* addr, socklen_t addrlen) =
21 (int (*)(int, const sockaddr*, socklen_t))dlsym(RTLD_NEXT, "bind");
22
bind(int sockfd,const sockaddr * addr,socklen_t addrlen)23 extern "C" int bind(int sockfd, const sockaddr* addr, socklen_t addrlen) {
24 if (addr->sa_family != AF_INET) return real_bind(sockfd, addr, addrlen);
25 const sockaddr_in* sin = (const sockaddr_in*)addr;
26 if (sin->sin_addr.s_addr != 0) return real_bind(sockfd, addr, addrlen);
27 sockaddr_in new_sin = *sin;
28 new_sin.sin_addr.s_addr = 0x0100007f;
29 return real_bind(sockfd, (sockaddr*)&new_sin, addrlen);
30 }
31