xref: /dragonfly/lib/libc/rpc/bindresvport.c (revision f9a239ec)
1 /*
2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3  * unrestricted use provided that this legend is included on all tape
4  * media and as a part of the software program in whole or part.  Users
5  * may copy or modify Sun RPC without charge, but are not authorized
6  * to license or distribute it to anyone else except as part of a product or
7  * program developed by the user.
8  *
9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
12  *
13  * Sun RPC is provided with no support and without any obligation on the
14  * part of Sun Microsystems, Inc. to assist in its use, correction,
15  * modification or enhancement.
16  *
17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
19  * OR ANY PART THEREOF.
20  *
21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
22  * or profits or other special, indirect and consequential damages, even if
23  * Sun has been advised of the possibility of such damages.
24  *
25  * Sun Microsystems, Inc.
26  * 2550 Garcia Avenue
27  * Mountain View, California  94043
28  *
29  * @(#)bindresvport.c 1.8 88/02/08 SMI
30  * @(#)bindresvport.c	2.2 88/07/29 4.0 RPCSRC
31  * $FreeBSD: src/lib/libc/rpc/bindresvport.c,v 1.12 2000/01/26 09:02:42 shin Exp $
32  * $DragonFly: src/lib/libc/rpc/bindresvport.c,v 1.3 2005/01/31 22:29:38 dillon Exp $
33  */
34 
35 /*
36  * Copyright (c) 1987 by Sun Microsystems, Inc.
37  *
38  * Portions Copyright(C) 1996, Jason Downs.  All rights reserved.
39  */
40 
41 #include "namespace.h"
42 #include <sys/types.h>
43 #include <sys/errno.h>
44 #include <sys/socket.h>
45 #include <netinet/in.h>
46 #include <unistd.h>
47 #include <string.h>
48 #include "un-namespace.h"
49 
50 /*
51  * Bind a socket to a privileged IP port
52  */
53 int
54 bindresvport(sd, sin)
55 	int sd;
56 	struct sockaddr_in *sin;
57 {
58 	return bindresvport_sa(sd, (struct sockaddr *)sin);
59 }
60 
61 /*
62  * Bind a socket to a privileged port for whatever protocol.
63  */
64 int
65 bindresvport_sa(sd, sa)
66 	int sd;
67 	struct sockaddr *sa;
68 {
69 	int old, error, af;
70 	struct sockaddr_storage myaddr;
71 	struct sockaddr_in *sin;
72 	struct sockaddr_in6 *sin6;
73 	int proto, portrange, portlow;
74 	u_int16_t port;
75 	int salen;
76 
77 	if (sa == NULL) {
78 		salen = sizeof(myaddr);
79 		sa = (struct sockaddr *)&myaddr;
80 
81 		if (_getsockname(sd, sa, &salen) == -1)
82 			return -1;	/* errno is correctly set */
83 
84 		af = sa->sa_family;
85 		memset(&myaddr, 0, salen);
86 	} else
87 		af = sa->sa_family;
88 
89 	if (af == AF_INET) {
90 		proto = IPPROTO_IP;
91 		portrange = IP_PORTRANGE;
92 		portlow = IP_PORTRANGE_LOW;
93 		sin = (struct sockaddr_in *)sa;
94 		salen = sizeof(struct sockaddr_in);
95 		port = sin->sin_port;
96 	} else if (af == AF_INET6) {
97 		proto = IPPROTO_IPV6;
98 		portrange = IPV6_PORTRANGE;
99 		portlow = IPV6_PORTRANGE_LOW;
100 		sin6 = (struct sockaddr_in6 *)sa;
101 		salen = sizeof(struct sockaddr_in6);
102 		port = sin6->sin6_port;
103 	} else {
104 		errno = EPFNOSUPPORT;
105 		return (-1);
106 	}
107 	sa->sa_family = af;
108 	sa->sa_len = salen;
109 
110 	if (port == 0) {
111 		int oldlen = sizeof(old);
112 
113 		error = _getsockopt(sd, proto, portrange, &old, &oldlen);
114 		if (error < 0)
115 			return (error);
116 
117 		error = setsockopt(sd, proto, portrange, &portlow,
118 		    sizeof(portlow));
119 		if (error < 0)
120 			return (error);
121 	}
122 
123 	error = _bind(sd, sa, salen);
124 
125 	if (port == 0) {
126 		int saved_errno = errno;
127 
128 		if (error) {
129 			if (_setsockopt(sd, proto, portrange, &old,
130 			    sizeof(old)) < 0)
131 				errno = saved_errno;
132 			return (error);
133 		}
134 
135 		if (sa != (struct sockaddr *)&myaddr) {
136 			/* Hmm, what did the kernel assign... */
137 			if (_getsockname(sd, sa, &salen) < 0)
138 				errno = saved_errno;
139 			return (error);
140 		}
141 	}
142 	return (error);
143 }
144