xref: /freebsd/lib/libc/rpc/bindresvport.c (revision dcc4d2939f789a6d1f272ffeab2068ba2b7525ea)
1 /*	$NetBSD: bindresvport.c,v 1.19 2000/07/06 03:03:59 christos Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  * Copyright (c) 2009, Sun Microsystems, Inc.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions are met:
11  * - Redistributions of source code must retain the above copyright notice,
12  *   this list of conditions and the following disclaimer.
13  * - Redistributions in binary form must reproduce the above copyright notice,
14  *   this list of conditions and the following disclaimer in the documentation
15  *   and/or other materials provided with the distribution.
16  * - Neither the name of Sun Microsystems, Inc. nor the names of its
17  *   contributors may be used to endorse or promote products derived
18  *   from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
24  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #if defined(LIBC_SCCS) && !defined(lint)
34 static char *sccsid2 = "from: @(#)bindresvport.c 1.8 88/02/08 SMI";
35 static char *sccsid = "from: @(#)bindresvport.c	2.2 88/07/29 4.0 RPCSRC";
36 #endif
37 /* from: $OpenBSD: bindresvport.c,v 1.7 1996/07/30 16:25:47 downsj Exp $ */
38 /*
39  * Copyright (c) 1987 by Sun Microsystems, Inc.
40  *
41  * Portions Copyright(C) 1996, Jason Downs.  All rights reserved.
42  */
43 
44 #include "namespace.h"
45 #include <sys/types.h>
46 #include <sys/socket.h>
47 
48 #include <netinet/in.h>
49 
50 #include <errno.h>
51 #include <string.h>
52 #include <unistd.h>
53 
54 #include <rpc/rpc.h>
55 
56 #include <string.h>
57 #include "un-namespace.h"
58 
59 /*
60  * Bind a socket to a privileged IP port
61  */
62 int
63 bindresvport(int sd, struct sockaddr_in *sin)
64 {
65 	return bindresvport_sa(sd, (struct sockaddr *)sin);
66 }
67 
68 /*
69  * Bind a socket to a privileged IP port
70  */
71 int
72 bindresvport_sa(int sd, struct sockaddr *sa)
73 {
74 	int old, error, af;
75 	struct sockaddr_storage myaddr;
76 	struct sockaddr_in *sin;
77 #ifdef INET6
78 	struct sockaddr_in6 *sin6;
79 #endif
80 	int proto, portrange, portlow;
81 	u_int16_t *portp;
82 	socklen_t salen;
83 
84 	if (sa == NULL) {
85 		salen = sizeof(myaddr);
86 		sa = (struct sockaddr *)&myaddr;
87 
88 		if (_getsockname(sd, sa, &salen) == -1)
89 			return -1;	/* errno is correctly set */
90 
91 		af = sa->sa_family;
92 		memset(sa, 0, salen);
93 	} else
94 		af = sa->sa_family;
95 
96 	switch (af) {
97 	case AF_INET:
98 		proto = IPPROTO_IP;
99 		portrange = IP_PORTRANGE;
100 		portlow = IP_PORTRANGE_LOW;
101 		sin = (struct sockaddr_in *)sa;
102 		salen = sizeof(struct sockaddr_in);
103 		portp = &sin->sin_port;
104 		break;
105 #ifdef INET6
106 	case AF_INET6:
107 		proto = IPPROTO_IPV6;
108 		portrange = IPV6_PORTRANGE;
109 		portlow = IPV6_PORTRANGE_LOW;
110 		sin6 = (struct sockaddr_in6 *)sa;
111 		salen = sizeof(struct sockaddr_in6);
112 		portp = &sin6->sin6_port;
113 		break;
114 #endif
115 	default:
116 		errno = EPFNOSUPPORT;
117 		return (-1);
118 	}
119 	sa->sa_family = af;
120 	sa->sa_len = salen;
121 
122 	if (*portp == 0) {
123 		socklen_t oldlen = sizeof(old);
124 
125 		error = _getsockopt(sd, proto, portrange, &old, &oldlen);
126 		if (error < 0)
127 			return (error);
128 
129 		error = _setsockopt(sd, proto, portrange, &portlow,
130 		    sizeof(portlow));
131 		if (error < 0)
132 			return (error);
133 	}
134 
135 	error = _bind(sd, sa, salen);
136 
137 	if (*portp == 0) {
138 		int saved_errno = errno;
139 
140 		if (error < 0) {
141 			if (_setsockopt(sd, proto, portrange, &old,
142 			    sizeof(old)) < 0)
143 				errno = saved_errno;
144 			return (error);
145 		}
146 
147 		if (sa != (struct sockaddr *)&myaddr) {
148 			/* Hmm, what did the kernel assign? */
149 			if (_getsockname(sd, sa, &salen) < 0)
150 				errno = saved_errno;
151 			return (error);
152 		}
153 	}
154 	return (error);
155 }
156