1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *  * Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *  * Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <netinet/in.h>
30
31#include <errno.h>
32#include <sys/types.h>
33#include <sys/socket.h>
34#include <string.h>
35#include <unistd.h>
36
37constexpr int START_PORT = 600;
38constexpr int END_PORT = IPPORT_RESERVED;
39constexpr int NUM_PORTS = (END_PORT - START_PORT);
40
41int bindresvport(int sd, struct sockaddr_in* sin) {
42  sockaddr_in sin0;
43  if (sin == nullptr) {
44    memset(&sin0, 0, sizeof(sin0));
45    sin = &sin0;
46    sin->sin_family = AF_INET;
47  }
48
49  if (sin->sin_family != AF_INET) {
50    errno = EPFNOSUPPORT;
51    return -1;
52  }
53
54  // TODO: thread safety!
55  static short port;
56  if (port == 0) {
57    port = START_PORT + (getpid() % NUM_PORTS);
58  }
59
60  for (size_t i = NUM_PORTS; i > 0; i--, port++) {
61    if (port == END_PORT) port = START_PORT;
62    sin->sin_port = htons(port);
63    int rc = TEMP_FAILURE_RETRY(bind(sd, reinterpret_cast<sockaddr*>(sin), sizeof(*sin)));
64    if (rc >= 0) return rc;
65  }
66  return -1;
67}
68
69const in6_addr in6addr_any = IN6ADDR_ANY_INIT;
70const in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
71