1/* $NetBSD: bindresvport.c,v 1.25 2013/03/11 20:19:28 tron Exp $ */
2
3/*
4 * Copyright (c) 2010, Oracle America, Inc.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met:
9 *
10 * * Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * * Redistributions in binary form must reproduce the above
13 * copyright notice, this list of conditions and the following
14 * disclaimer in the documentation and/or other materials
15 * provided with the distribution.
16 * * Neither the name of the "Oracle America, 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
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
25 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#include <sys/cdefs.h>
35#if defined(LIBC_SCCS) && !defined(lint)
36#if 0
37static char *sccsid = "@(#)bindresvport.c 1.8 88/02/08 SMI";
38static char *sccsid = "@(#)bindresvport.c 2.2 88/07/29 4.0 RPCSRC";
39#else
40__RCSID("$NetBSD: bindresvport.c,v 1.25 2013/03/11 20:19:28 tron Exp $");
41#endif
42#endif
43
44/*
45 * Copyright (c) 1987 by Sun Microsystems, Inc.
46 */
47
48#include "namespace.h"
49
50#include <sys/types.h>
51#include <sys/socket.h>
52
53#include <netinet/in.h>
54
55#include <errno.h>
56#include <string.h>
57#include <unistd.h>
58
59#include <rpc/rpc.h>
60#include "svc_fdset.h"
61
62#ifdef __weak_alias
63__weak_alias(bindresvport,_bindresvport)
64__weak_alias(bindresvport_sa,_bindresvport_sa)
65#endif
66
67/*
68 * Bind a socket to a privileged IP port
69 */
70int
71bindresvport(int sd, struct sockaddr_in *brsin)
72{
73 return bindresvport_sa(sd, (struct sockaddr *)(void *)brsin);
74}
75
76/*
77 * Bind a socket to a privileged IP port
78 */
79int
80bindresvport_sa(int sd, struct sockaddr *sa)
81{
82 int error, old;
83 struct sockaddr_storage myaddr;
84 struct sockaddr_in *brsin;
85#ifdef INET6
86 struct sockaddr_in6 *brsin6;
87#endif
88 int proto, portrange, portlow;
89 u_int16_t *portp;
90 socklen_t salen;
91 int af;
92
93 if (sa == NULL) {
94 salen = sizeof(myaddr);
95 sa = (struct sockaddr *)(void *)&myaddr;
96
97 if (getsockname(sd, sa, &salen) == -1)
98 return -1; /* errno is correctly set */
99
100 af = sa->sa_family;
101 memset(sa, 0, salen);
102 } else
103 af = sa->sa_family;
104
105 switch (af) {
106 case AF_INET:
107 proto = IPPROTO_IP;
108 portrange = IP_PORTRANGE;
109 portlow = IP_PORTRANGE_LOW;
110 brsin = (struct sockaddr_in *)(void *)sa;
111 salen = sizeof(struct sockaddr_in);
112 portp = &brsin->sin_port;
113 break;
114#ifdef INET6
115 case AF_INET6:
116 proto = IPPROTO_IPV6;
117 portrange = IPV6_PORTRANGE;
118 portlow = IPV6_PORTRANGE_LOW;
119 brsin6 = (struct sockaddr_in6 *)(void *)sa;
120 salen = sizeof(struct sockaddr_in6);
121 portp = &brsin6->sin6_port;
122 break;
123#endif
124 default:
125 errno = EPFNOSUPPORT;
126 return (-1);
127 }
128 sa->sa_family = af;
129 sa->sa_len = salen;
130
131 if (*portp == 0) {
132 socklen_t oldlen = sizeof(old);
133
134 error = getsockopt(sd, proto, portrange, &old, &oldlen);
135 if (error < 0)
136 return (error);
137 error = setsockopt(sd, proto, portrange, &portlow,
138 (socklen_t)sizeof(portlow));
139 if (error < 0)
140 return (error);
141 }
142
143 error = bind(sd, sa, salen);
144
145 if (*portp == 0) {
146 int saved_errno = errno;
147
148 if (error < 0) {
149 if (setsockopt(sd, proto, portrange, &old,
150 (socklen_t)sizeof(old)) < 0)
151 errno = saved_errno;
152 return (error);
153 }
154
155 if (sa != (struct sockaddr *)(void *)&myaddr) {
156 /* What did the kernel assign? */
157 if (getsockname(sd, sa, &salen) < 0)
158 errno = saved_errno;
159 return (error);
160 }
161 }
162 return (error);
163}
164