1/*
2 * Copyright (C) 2014 Linux Test Project, Inc.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of version 2 of the GNU General Public
6 * License as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it would be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11 *
12 * Further, this software is distributed without any warranty that it
13 * is free of the rightful claim of any third person regarding
14 * infringement or the like.  Any license provided herein, whether
15 * implied or otherwise, applies only to this software file.  Patent
16 * licenses, if any, provided herein do not apply to combinations of
17 * this program with other software, or any other product whatsoever.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write the Free Software Foundation, Inc.
21 */
22
23#include <sys/types.h>
24#include <sys/socket.h>
25#include <netinet/in.h>
26
27#include "test.h"
28
29unsigned short tst_get_unused_port(void (cleanup_fn)(void),
30	unsigned short family, int type)
31{
32	int sock;
33	socklen_t slen;
34	struct sockaddr_storage _addr;
35	struct sockaddr *addr = (struct sockaddr *)&_addr;
36	struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
37	struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
38
39	switch (family) {
40	case AF_INET:
41		addr4->sin_family = AF_INET;
42		addr4->sin_port = 0;
43		addr4->sin_addr.s_addr = INADDR_ANY;
44		slen = sizeof(*addr4);
45		break;
46
47	case AF_INET6:
48		addr6->sin6_family = AF_INET6;
49		addr6->sin6_port = 0;
50		addr6->sin6_addr = in6addr_any;
51		slen = sizeof(*addr6);
52		break;
53
54	default:
55		tst_brkm(TBROK, cleanup_fn,
56			"tst_get_unused_port unknown family");
57		return -1;
58	}
59
60	sock = socket(addr->sa_family, type, 0);
61	if (sock < 0) {
62		tst_brkm(TBROK | TERRNO, cleanup_fn, "socket failed");
63		return -1;
64	}
65
66	if (bind(sock, addr, slen) < 0) {
67		tst_brkm(TBROK | TERRNO, cleanup_fn, "bind failed");
68		return -1;
69	}
70
71	if (getsockname(sock, addr, &slen) == -1) {
72		tst_brkm(TBROK | TERRNO, cleanup_fn, "getsockname failed");
73		return -1;
74	}
75
76	if (close(sock) == -1) {
77		tst_brkm(TBROK | TERRNO, cleanup_fn, "close failed");
78		return -1;
79	}
80
81	switch (family) {
82	case AF_INET:
83		return addr4->sin_port;
84	case AF_INET6:
85		return addr6->sin6_port;
86	default:
87		return -1;
88	}
89}
90