blob: 45da5af4a1b60a5e37bd8c76572835295ac5299c [file] [log] [blame]
/*
* Copyright (C) 2017 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "sysdeps/network.h"
#include <errno.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <string>
#include "adb_unique_fd.h"
static void set_error(std::string* error) {
if (error) {
*error = strerror(errno);
}
}
static sockaddr* loopback_addr4(sockaddr_storage* addr, socklen_t* addrlen, int port) {
struct sockaddr_in* addr4 = reinterpret_cast<sockaddr_in*>(addr);
*addrlen = sizeof(*addr4);
addr4->sin_family = AF_INET;
addr4->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
addr4->sin_port = htons(port);
return reinterpret_cast<sockaddr*>(addr);
}
static sockaddr* loopback_addr6(sockaddr_storage* addr, socklen_t* addrlen, int port) {
struct sockaddr_in6* addr6 = reinterpret_cast<sockaddr_in6*>(addr);
*addrlen = sizeof(*addr6);
addr6->sin6_family = AF_INET6;
addr6->sin6_addr = in6addr_loopback;
addr6->sin6_port = htons(port);
return reinterpret_cast<sockaddr*>(addr);
}
static int _network_loopback_client(bool ipv6, int port, int type, std::string* error) {
unique_fd s(socket(ipv6 ? AF_INET6 : AF_INET, type, 0));
if (s == -1) {
set_error(error);
return -1;
}
struct sockaddr_storage addr_storage = {};
socklen_t addrlen = sizeof(addr_storage);
sockaddr* addr = (ipv6 ? loopback_addr6 : loopback_addr4)(&addr_storage, &addrlen, 0);
if (bind(s.get(), addr, addrlen) != 0) {
set_error(error);
return -1;
}
addr = (ipv6 ? loopback_addr6 : loopback_addr4)(&addr_storage, &addrlen, port);
if (connect(s.get(), addr, addrlen) != 0) {
set_error(error);
return -1;
}
return s.release();
}
int network_loopback_client(int port, int type, std::string* error) {
// Try IPv4 first, use IPv6 as a fallback.
int rc = _network_loopback_client(false, port, type, error);
if (rc == -1) {
return _network_loopback_client(true, port, type, error);
}
return rc;
}
static int _network_loopback_server(bool ipv6, int port, int type, std::string* error) {
unique_fd s(socket(ipv6 ? AF_INET6 : AF_INET, type, 0));
if (s == -1) {
set_error(error);
return -1;
}
int n = 1;
setsockopt(s.get(), SOL_SOCKET, SO_REUSEADDR, &n, sizeof(n));
struct sockaddr_storage addr_storage = {};
socklen_t addrlen = sizeof(addr_storage);
sockaddr* addr = (ipv6 ? loopback_addr6 : loopback_addr4)(&addr_storage, &addrlen, port);
if (bind(s, addr, addrlen) != 0) {
set_error(error);
return -1;
}
if (type == SOCK_STREAM || type == SOCK_SEQPACKET) {
// Arbitrarily selected value, ported from libcutils.
if (listen(s, 4) != 0) {
set_error(error);
return -1;
}
}
return s.release();
}
int network_loopback_server(int port, int type, std::string* error) {
int rc = _network_loopback_server(false, port, type, error);
// Only attempt to listen on IPv6 if IPv4 is unavailable.
// We don't want to start an IPv6 server if there's already an IPv4 one running.
if (rc == -1 && (errno == EADDRNOTAVAIL || errno == EAFNOSUPPORT)) {
return _network_loopback_server(true, port, type, error);
}
return rc;
}