xref: /freebsd/lib/libc/rpc/bindresvport.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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 #include <sys/cdefs.h>
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  */
63 int
64 bindresvport(int sd, struct sockaddr_in *sin)
65 {
66 	return bindresvport_sa(sd, (struct sockaddr *)sin);
67 }
68 
69 /*
70  * Bind a socket to a privileged IP port
71  */
72 int
73 bindresvport_sa(int sd, struct sockaddr *sa)
74 {
75 	int old, error, af;
76 	struct sockaddr_storage myaddr;
77 	struct sockaddr_in *sin;
78 #ifdef INET6
79 	struct sockaddr_in6 *sin6;
80 #endif
81 	int proto, portrange, portlow;
82 	u_int16_t *portp;
83 	socklen_t salen;
84 
85 	if (sa == NULL) {
86 		salen = sizeof(myaddr);
87 		sa = (struct sockaddr *)&myaddr;
88 
89 		if (_getsockname(sd, sa, &salen) == -1)
90 			return -1;	/* errno is correctly set */
91 
92 		af = sa->sa_family;
93 		memset(sa, 0, salen);
94 	} else
95 		af = sa->sa_family;
96 
97 	switch (af) {
98 	case AF_INET:
99 		proto = IPPROTO_IP;
100 		portrange = IP_PORTRANGE;
101 		portlow = IP_PORTRANGE_LOW;
102 		sin = (struct sockaddr_in *)sa;
103 		salen = sizeof(struct sockaddr_in);
104 		portp = &sin->sin_port;
105 		break;
106 #ifdef INET6
107 	case AF_INET6:
108 		proto = IPPROTO_IPV6;
109 		portrange = IPV6_PORTRANGE;
110 		portlow = IPV6_PORTRANGE_LOW;
111 		sin6 = (struct sockaddr_in6 *)sa;
112 		salen = sizeof(struct sockaddr_in6);
113 		portp = &sin6->sin6_port;
114 		break;
115 #endif
116 	default:
117 		errno = EPFNOSUPPORT;
118 		return (-1);
119 	}
120 	sa->sa_family = af;
121 	sa->sa_len = salen;
122 
123 	if (*portp == 0) {
124 		socklen_t oldlen = sizeof(old);
125 
126 		error = _getsockopt(sd, proto, portrange, &old, &oldlen);
127 		if (error < 0)
128 			return (error);
129 
130 		error = _setsockopt(sd, proto, portrange, &portlow,
131 		    sizeof(portlow));
132 		if (error < 0)
133 			return (error);
134 	}
135 
136 	error = _bind(sd, sa, salen);
137 
138 	if (*portp == 0) {
139 		int saved_errno = errno;
140 
141 		if (error < 0) {
142 			if (_setsockopt(sd, proto, portrange, &old,
143 			    sizeof(old)) < 0)
144 				errno = saved_errno;
145 			return (error);
146 		}
147 
148 		if (sa != (struct sockaddr *)&myaddr) {
149 			/* Hmm, what did the kernel assign? */
150 			if (_getsockname(sd, sa, &salen) < 0)
151 				errno = saved_errno;
152 			return (error);
153 		}
154 	}
155 	return (error);
156 }
157