bindresvport.c revision 1.15 
1/*	$NetBSD: bindresvport.c,v 1.15 1999/05/03 15:32:13 christos Exp $	*/
2
3/*
4 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
5 * unrestricted use provided that this legend is included on all tape
6 * media and as a part of the software program in whole or part.  Users
7 * may copy or modify Sun RPC without charge, but are not authorized
8 * to license or distribute it to anyone else except as part of a product or
9 * program developed by the user.
10 *
11 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
12 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
13 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
14 *
15 * Sun RPC is provided with no support and without any obligation on the
16 * part of Sun Microsystems, Inc. to assist in its use, correction,
17 * modification or enhancement.
18 *
19 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
20 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
21 * OR ANY PART THEREOF.
22 *
23 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
24 * or profits or other special, indirect and consequential damages, even if
25 * Sun has been advised of the possibility of such damages.
26 *
27 * Sun Microsystems, Inc.
28 * 2550 Garcia Avenue
29 * Mountain View, California  94043
30 */
31
32#include <sys/cdefs.h>
33#if defined(LIBC_SCCS) && !defined(lint)
34#if 0
35static char *sccsid = "@(#)bindresvport.c 1.8 88/02/08 SMI";
36static char *sccsid = "@(#)bindresvport.c	2.2 88/07/29 4.0 RPCSRC";
37#else
38__RCSID("$NetBSD: bindresvport.c,v 1.15 1999/05/03 15:32:13 christos Exp $");
39#endif
40#endif
41
42/*
43 * Copyright (c) 1987 by Sun Microsystems, Inc.
44 */
45
46#include "namespace.h"
47
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#ifdef __weak_alias
60__weak_alias(bindresvport,_bindresvport);
61#endif
62
63/*
64 * Bind a socket to a privileged IP port
65 */
66int
67bindresvport(sd, sin)
68	int sd;
69	struct sockaddr_in *sin;
70{
71	int res, old;
72	struct sockaddr_in myaddr;
73	socklen_t sinlen = sizeof(struct sockaddr_in);
74
75	if (sin == NULL) {
76		sin = &myaddr;
77		memset(sin, 0, (size_t)sinlen);
78		sin->sin_len = sinlen;
79		sin->sin_family = AF_INET;
80	} else if (sin->sin_family != AF_INET) {
81		errno = EPFNOSUPPORT;
82		return (-1);
83	}
84
85	if (sin->sin_port == 0) {
86		int on;
87		socklen_t oldlen = sizeof(old);
88
89		res = getsockopt(sd, IPPROTO_IP, IP_PORTRANGE, &old, &oldlen);
90		if (res < 0)
91			return(res);
92		on = IP_PORTRANGE_LOW;
93		res = setsockopt(sd, IPPROTO_IP, IP_PORTRANGE, &on, sizeof(on));
94		if (res < 0)
95			return(res);
96	}
97
98	res = bind(sd, (struct sockaddr *)(void *)sin, sinlen);
99
100	if (sin->sin_port == 0) {
101		int saved_errno = errno;
102
103		if (res < 0) {
104			if (setsockopt(sd, IPPROTO_IP, IP_PORTRANGE,
105			    &old, sizeof(old)) < 0)
106				errno = saved_errno;
107			return (res);
108		}
109
110		if (sin != &myaddr) {	/* What did the kernel assign? */
111			if (getsockname(sd, (struct sockaddr *)(void *)sin,
112			    &sinlen) < 0)
113				errno = saved_errno;
114			return (res);
115		}
116	}
117	return (res);
118}
119