xref: /netbsd/lib/libc/rpc/bindresvport.c (revision bf9ec67e)
1 /*	$NetBSD: bindresvport.c,v 1.20 2001/11/04 13:57:30 lukem 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
35 static char *sccsid = "@(#)bindresvport.c 1.8 88/02/08 SMI";
36 static char *sccsid = "@(#)bindresvport.c	2.2 88/07/29 4.0 RPCSRC";
37 #else
38 __RCSID("$NetBSD: bindresvport.c,v 1.20 2001/11/04 13:57:30 lukem 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 __weak_alias(bindresvport_sa,_bindresvport_sa)
62 #endif
63 
64 /*
65  * Bind a socket to a privileged IP port
66  */
67 int
68 bindresvport(sd, brsin)
69 	int sd;
70 	struct sockaddr_in *brsin;
71 {
72 	return bindresvport_sa(sd, (struct sockaddr *)(void *)brsin);
73 }
74 
75 /*
76  * Bind a socket to a privileged IP port
77  */
78 int
79 bindresvport_sa(sd, sa)
80 	int sd;
81 	struct sockaddr *sa;
82 {
83 	int error, old;
84 	struct sockaddr_storage myaddr;
85 	struct sockaddr_in *brsin;
86 #ifdef INET6
87 	struct sockaddr_in6 *brsin6;
88 #endif
89 	int proto, portrange, portlow;
90 	u_int16_t *portp;
91 	socklen_t salen;
92 	int af;
93 
94 	if (sa == NULL) {
95 		salen = sizeof(myaddr);
96 		sa = (struct sockaddr *)(void *)&myaddr;
97 
98 		if (getsockname(sd, sa, &salen) == -1)
99 			return -1;	/* errno is correctly set */
100 
101 		af = sa->sa_family;
102 		memset(sa, 0, salen);
103 	} else
104 		af = sa->sa_family;
105 
106 	switch (af) {
107 	case AF_INET:
108 		proto = IPPROTO_IP;
109 		portrange = IP_PORTRANGE;
110 		portlow = IP_PORTRANGE_LOW;
111 		brsin = (struct sockaddr_in *)(void *)sa;
112 		salen = sizeof(struct sockaddr_in);
113 		portp = &brsin->sin_port;
114 		break;
115 #ifdef INET6
116 	case AF_INET6:
117 		proto = IPPROTO_IPV6;
118 		portrange = IPV6_PORTRANGE;
119 		portlow = IPV6_PORTRANGE_LOW;
120 		brsin6 = (struct sockaddr_in6 *)(void *)sa;
121 		salen = sizeof(struct sockaddr_in6);
122 		portp = &brsin6->sin6_port;
123 		break;
124 #endif
125 	default:
126 		errno = EPFNOSUPPORT;
127 		return (-1);
128 	}
129 	sa->sa_family = af;
130 	sa->sa_len = salen;
131 
132 	if (*portp == 0) {
133 		socklen_t oldlen = sizeof(old);
134 
135 		error = getsockopt(sd, proto, portrange, &old, &oldlen);
136 		if (error < 0)
137 			return (error);
138 		error = setsockopt(sd, proto, portrange, &portlow,
139 		    sizeof(portlow));
140 		if (error < 0)
141 			return (error);
142 	}
143 
144 	error = bind(sd, sa, salen);
145 
146 	if (*portp == 0) {
147 		int saved_errno = errno;
148 
149 		if (error < 0) {
150 			if (setsockopt(sd, proto, portrange, &old,
151 			    sizeof(old)) < 0)
152 				errno = saved_errno;
153 			return (error);
154 		}
155 
156 		if (sa != (struct sockaddr *)(void *)&myaddr) {
157 			/* What did the kernel assign? */
158 			if (getsockname(sd, sa, &salen) < 0)
159 				errno = saved_errno;
160 			return (error);
161 		}
162 	}
163 	return (error);
164 }
165