xref: /dragonfly/lib/libc/rpc/bindresvport.c (revision 9348a738)
1 /*-
2  * Copyright (c) 2009, Sun Microsystems, Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  * - Redistributions of source code must retain the above copyright notice,
8  *   this list of conditions and the following disclaimer.
9  * - Redistributions in binary form must reproduce the above copyright notice,
10  *   this list of conditions and the following disclaimer in the documentation
11  *   and/or other materials provided with the distribution.
12  * - Neither the name of Sun Microsystems, Inc. nor the names of its
13  *   contributors may be used to endorse or promote products derived
14  *   from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  *
28  * @(#)bindresvport.c 1.8 88/02/08 SMI
29  * @(#)bindresvport.c	2.2 88/07/29 4.0 RPCSRC
30  * $NetBSD: bindresvport.c,v 1.19 2000/07/06 03:03:59 christos Exp $
31  * $FreeBSD: src/lib/libc/rpc/bindresvport.c,v 1.16 2004/10/16 06:11:34 obrien Exp $
32  */
33 
34 /*
35  * Copyright (c) 1987 by Sun Microsystems, Inc.
36  *
37  * Portions Copyright(C) 1996, Jason Downs.  All rights reserved.
38  */
39 
40 #include "namespace.h"
41 #include <sys/types.h>
42 #include <sys/socket.h>
43 
44 #include <netinet/in.h>
45 
46 #include <errno.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 #include <rpc/rpc.h>
51 #include "un-namespace.h"
52 
53 /*
54  * Bind a socket to a privileged IP port
55  */
56 int
57 bindresvport(int sd, struct sockaddr_in *sin)
58 {
59 	return bindresvport_sa(sd, (struct sockaddr *)sin);
60 }
61 
62 /*
63  * Bind a socket to a privileged IP port
64  */
65 int
66 bindresvport_sa(int sd, struct sockaddr *sa)
67 {
68 	int old, error, af;
69 	struct sockaddr_storage myaddr;
70 	struct sockaddr_in *sin;
71 #ifdef INET6
72 	struct sockaddr_in6 *sin6;
73 #endif
74 	int proto, portrange, portlow;
75 	u_int16_t *portp;
76 	socklen_t salen;
77 
78 	if (sa == NULL) {
79 		salen = sizeof(myaddr);
80 		sa = (struct sockaddr *)&myaddr;
81 
82 		if (_getsockname(sd, sa, &salen) == -1)
83 			return -1;	/* errno is correctly set */
84 
85 		af = sa->sa_family;
86 		memset(sa, 0, salen);
87 	} else
88 		af = sa->sa_family;
89 
90 	switch (af) {
91 	case AF_INET:
92 		proto = IPPROTO_IP;
93 		portrange = IP_PORTRANGE;
94 		portlow = IP_PORTRANGE_LOW;
95 		sin = (struct sockaddr_in *)sa;
96 		salen = sizeof(struct sockaddr_in);
97 		portp = &sin->sin_port;
98 		break;
99 #ifdef INET6
100 	case AF_INET6:
101 		proto = IPPROTO_IPV6;
102 		portrange = IPV6_PORTRANGE;
103 		portlow = IPV6_PORTRANGE_LOW;
104 		sin6 = (struct sockaddr_in6 *)sa;
105 		salen = sizeof(struct sockaddr_in6);
106 		portp = &sin6->sin6_port;
107 		break;
108 #endif
109 	default:
110 		errno = EPFNOSUPPORT;
111 		return (-1);
112 	}
113 	sa->sa_family = af;
114 	sa->sa_len = salen;
115 
116 	if (*portp == 0) {
117 		socklen_t oldlen = sizeof(old);
118 
119 		error = _getsockopt(sd, proto, portrange, &old, &oldlen);
120 		if (error < 0)
121 			return (error);
122 
123 		error = _setsockopt(sd, proto, portrange, &portlow,
124 		    sizeof(portlow));
125 		if (error < 0)
126 			return (error);
127 	}
128 
129 	error = _bind(sd, sa, salen);
130 
131 	if (*portp == 0) {
132 		int saved_errno = errno;
133 
134 		if (error < 0) {
135 			if (_setsockopt(sd, proto, portrange, &old,
136 			    sizeof(old)) < 0)
137 				errno = saved_errno;
138 			return (error);
139 		}
140 
141 		if (sa != (struct sockaddr *)&myaddr) {
142 			/* Hmm, what did the kernel assign? */
143 			if (_getsockname(sd, sa, &salen) < 0)
144 				errno = saved_errno;
145 			return (error);
146 		}
147 	}
148 	return (error);
149 }
150