summaryrefslogtreecommitdiff
path: root/lib/libc/rpc/bindresvport.c
blob: 53a1339206d7f65daac0a508f205af84ccdf01b8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
/*
 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
 * unrestricted use provided that this legend is included on all tape
 * media and as a part of the software program in whole or part.  Users
 * may copy or modify Sun RPC without charge, but are not authorized
 * to license or distribute it to anyone else except as part of a product or
 * program developed by the user.
 * 
 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
 * 
 * Sun RPC is provided with no support and without any obligation on the
 * part of Sun Microsystems, Inc. to assist in its use, correction,
 * modification or enhancement.
 * 
 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
 * OR ANY PART THEREOF.
 * 
 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
 * or profits or other special, indirect and consequential damages, even if
 * Sun has been advised of the possibility of such damages.
 * 
 * Sun Microsystems, Inc.
 * 2550 Garcia Avenue
 * Mountain View, California  94043
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$OpenBSD: bindresvport.c,v 1.14 2002/09/06 18:35:12 deraadt Exp $";
#endif /* LIBC_SCCS and not lint */

/*
 * Copyright (c) 1987 by Sun Microsystems, Inc.
 *
 * Portions Copyright(C) 1996, Jason Downs.  All rights reserved.
 */

#include <string.h>
#include <sys/types.h>
#include <sys/errno.h>
#include <sys/socket.h>
#include <netinet/in.h>

/*
 * Bind a socket to a privileged IP port
 */
int
bindresvport(sd, sin)
	int sd;
	struct sockaddr_in *sin;
{
	return bindresvport_sa(sd, (struct sockaddr *)sin);
}

/*
 * Bind a socket to a privileged port for whatever protocol.
 */
int
bindresvport_sa(sd, sa)
	int sd;
	struct sockaddr *sa;
{
	int old, error, af;
	struct sockaddr_storage myaddr;
	struct sockaddr_in *sin;
	struct sockaddr_in6 *sin6;
	int proto, portrange, portlow;
	u_int16_t port;
	socklen_t salen;

	if (sa == NULL) {
		salen = sizeof(myaddr);
		sa = (struct sockaddr *)&myaddr;

		if (getsockname(sd, sa, &salen) == -1)
			return -1;	/* errno is correctly set */

		af = sa->sa_family;
		memset(&myaddr, 0, salen);
	} else
		af = sa->sa_family;

	if (af == AF_INET) {
		proto = IPPROTO_IP;
		portrange = IP_PORTRANGE;
		portlow = IP_PORTRANGE_LOW;
		sin = (struct sockaddr_in *)sa;
		salen = sizeof(struct sockaddr_in);
		port = sin->sin_port;
	} else if (af == AF_INET6) {
		proto = IPPROTO_IPV6;
		portrange = IPV6_PORTRANGE;
		portlow = IPV6_PORTRANGE_LOW;
		sin6 = (struct sockaddr_in6 *)sa;
		salen = sizeof(struct sockaddr_in6);
		port = sin6->sin6_port;
	} else {
		errno = EPFNOSUPPORT;
		return (-1);
	}
	sa->sa_family = af;
	sa->sa_len = salen;

	if (port == 0) {
		socklen_t oldlen = sizeof(old);

		error = getsockopt(sd, proto, portrange, &old, &oldlen);
		if (error < 0)
			return (error);

		error = setsockopt(sd, proto, portrange, &portlow,
		    sizeof(portlow));
		if (error < 0)
			return (error);
	}

	error = bind(sd, sa, salen);

	if (port == 0) {
		int saved_errno = errno;

		if (error) {
			if (setsockopt(sd, proto, portrange, &old,
			    sizeof(old)) < 0)
				errno = saved_errno;
			return (error);
		}

		if (sa != (struct sockaddr *)&myaddr) {
			/* Hmm, what did the kernel assign... */
			if (getsockname(sd, sa, &salen) < 0)
				errno = saved_errno;
			return (error);
		}
	}
	return (error);
}