xref: /freebsd/lib/libc/rpc/bindresvport.c (revision a7623790fb345e6dc986dfd31df0ace115e6f2e4)
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 __FBSDID("$FreeBSD$");
40 
41 /*
42  * Copyright (c) 1987 by Sun Microsystems, Inc.
43  *
44  * Portions Copyright(C) 1996, Jason Downs.  All rights reserved.
45  */
46 
47 #include "namespace.h"
48 #include <sys/types.h>
49 #include <sys/socket.h>
50 
51 #include <netinet/in.h>
52 
53 #include <errno.h>
54 #include <string.h>
55 #include <unistd.h>
56 
57 #include <rpc/rpc.h>
58 
59 #include <string.h>
60 #include "un-namespace.h"
61 
62 /*
63  * Bind a socket to a privileged IP port
64  */
65 int
66 bindresvport(int sd, 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  */
74 int
75 bindresvport_sa(int sd, struct sockaddr *sa)
76 {
77 	int old, error, af;
78 	struct sockaddr_storage myaddr;
79 	struct sockaddr_in *sin;
80 #ifdef INET6
81 	struct sockaddr_in6 *sin6;
82 #endif
83 	int proto, portrange, portlow;
84 	u_int16_t *portp;
85 	socklen_t salen;
86 
87 	if (sa == NULL) {
88 		salen = sizeof(myaddr);
89 		sa = (struct sockaddr *)&myaddr;
90 
91 		if (_getsockname(sd, sa, &salen) == -1)
92 			return -1;	/* errno is correctly set */
93 
94 		af = sa->sa_family;
95 		memset(sa, 0, salen);
96 	} else
97 		af = sa->sa_family;
98 
99 	switch (af) {
100 	case AF_INET:
101 		proto = IPPROTO_IP;
102 		portrange = IP_PORTRANGE;
103 		portlow = IP_PORTRANGE_LOW;
104 		sin = (struct sockaddr_in *)sa;
105 		salen = sizeof(struct sockaddr_in);
106 		portp = &sin->sin_port;
107 		break;
108 #ifdef INET6
109 	case AF_INET6:
110 		proto = IPPROTO_IPV6;
111 		portrange = IPV6_PORTRANGE;
112 		portlow = IPV6_PORTRANGE_LOW;
113 		sin6 = (struct sockaddr_in6 *)sa;
114 		salen = sizeof(struct sockaddr_in6);
115 		portp = &sin6->sin6_port;
116 		break;
117 #endif
118 	default:
119 		errno = EPFNOSUPPORT;
120 		return (-1);
121 	}
122 	sa->sa_family = af;
123 	sa->sa_len = salen;
124 
125 	if (*portp == 0) {
126 		socklen_t oldlen = sizeof(old);
127 
128 		error = _getsockopt(sd, proto, portrange, &old, &oldlen);
129 		if (error < 0)
130 			return (error);
131 
132 		error = _setsockopt(sd, proto, portrange, &portlow,
133 		    sizeof(portlow));
134 		if (error < 0)
135 			return (error);
136 	}
137 
138 	error = _bind(sd, sa, salen);
139 
140 	if (*portp == 0) {
141 		int saved_errno = errno;
142 
143 		if (error < 0) {
144 			if (_setsockopt(sd, proto, portrange, &old,
145 			    sizeof(old)) < 0)
146 				errno = saved_errno;
147 			return (error);
148 		}
149 
150 		if (sa != (struct sockaddr *)&myaddr) {
151 			/* Hmm, what did the kernel assign? */
152 			if (_getsockname(sd, sa, &salen) < 0)
153 				errno = saved_errno;
154 			return (error);
155 		}
156 	}
157 	return (error);
158 }
159