bindresvport.c revision 261046 
1/*	$NetBSD: bindresvport.c,v 1.19 2000/07/06 03:03:59 christos Exp $	*/
2
3/*-
4 * Copyright (c) 2009, Sun Microsystems, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 * - Redistributions of source code must retain the above copyright notice,
10 *   this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright notice,
12 *   this list of conditions and the following disclaimer in the documentation
13 *   and/or other materials provided with the distribution.
14 * - Neither the name of Sun Microsystems, Inc. nor the names of its
15 *   contributors may be used to endorse or promote products derived
16 *   from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#if defined(LIBC_SCCS) && !defined(lint)
32static char *sccsid2 = "from: @(#)bindresvport.c 1.8 88/02/08 SMI";
33static char *sccsid = "from: @(#)bindresvport.c	2.2 88/07/29 4.0 RPCSRC";
34#endif
35/* from: $OpenBSD: bindresvport.c,v 1.7 1996/07/30 16:25:47 downsj Exp $ */
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD: stable/10/lib/libc/rpc/bindresvport.c 261046 2014-01-22 23:45:27Z mav $");
38
39/*
40 * Copyright (c) 1987 by Sun Microsystems, Inc.
41 *
42 * Portions Copyright(C) 1996, Jason Downs.  All rights reserved.
43 */
44
45#include "namespace.h"
46#include <sys/types.h>
47#include <sys/socket.h>
48
49#include <netinet/in.h>
50
51#include <errno.h>
52#include <string.h>
53#include <unistd.h>
54
55#include <rpc/rpc.h>
56
57#include <string.h>
58#include "un-namespace.h"
59
60/*
61 * Bind a socket to a privileged IP port
62 */
63int
64bindresvport(sd, sin)
65	int sd;
66	struct sockaddr_in *sin;
67{
68	return bindresvport_sa(sd, (struct sockaddr *)sin);
69}
70
71/*
72 * Bind a socket to a privileged IP port
73 */
74int
75bindresvport_sa(sd, sa)
76	int sd;
77	struct sockaddr *sa;
78{
79	int old, error, af;
80	struct sockaddr_storage myaddr;
81	struct sockaddr_in *sin;
82#ifdef INET6
83	struct sockaddr_in6 *sin6;
84#endif
85	int proto, portrange, portlow;
86	u_int16_t *portp;
87	socklen_t salen;
88
89	if (sa == NULL) {
90		salen = sizeof(myaddr);
91		sa = (struct sockaddr *)&myaddr;
92
93		if (_getsockname(sd, sa, &salen) == -1)
94			return -1;	/* errno is correctly set */
95
96		af = sa->sa_family;
97		memset(sa, 0, salen);
98	} else
99		af = sa->sa_family;
100
101	switch (af) {
102	case AF_INET:
103		proto = IPPROTO_IP;
104		portrange = IP_PORTRANGE;
105		portlow = IP_PORTRANGE_LOW;
106		sin = (struct sockaddr_in *)sa;
107		salen = sizeof(struct sockaddr_in);
108		portp = &sin->sin_port;
109		break;
110#ifdef INET6
111	case AF_INET6:
112		proto = IPPROTO_IPV6;
113		portrange = IPV6_PORTRANGE;
114		portlow = IPV6_PORTRANGE_LOW;
115		sin6 = (struct sockaddr_in6 *)sa;
116		salen = sizeof(struct sockaddr_in6);
117		portp = &sin6->sin6_port;
118		break;
119#endif
120	default:
121		errno = EPFNOSUPPORT;
122		return (-1);
123	}
124	sa->sa_family = af;
125	sa->sa_len = salen;
126
127	if (*portp == 0) {
128		socklen_t oldlen = sizeof(old);
129
130		error = _getsockopt(sd, proto, portrange, &old, &oldlen);
131		if (error < 0)
132			return (error);
133
134		error = _setsockopt(sd, proto, portrange, &portlow,
135		    sizeof(portlow));
136		if (error < 0)
137			return (error);
138	}
139
140	error = _bind(sd, sa, salen);
141
142	if (*portp == 0) {
143		int saved_errno = errno;
144
145		if (error < 0) {
146			if (_setsockopt(sd, proto, portrange, &old,
147			    sizeof(old)) < 0)
148				errno = saved_errno;
149			return (error);
150		}
151
152		if (sa != (struct sockaddr *)&myaddr) {
153			/* Hmm, what did the kernel assign? */
154			if (_getsockname(sd, sa, &salen) < 0)
155				errno = saved_errno;
156			return (error);
157		}
158	}
159	return (error);
160}
161