xref: /titanic_44/usr/src/cmd/ssh/libopenbsd-compat/common/bindresvport.c (revision 5c51f1241dbbdf2656d0e10011981411ed0c9673)
1 /* This file has be modified from the original OpenBSD source */
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 "includes.h"
33 
34 #ifndef HAVE_BINDRESVPORT_SA
35 
36 #if defined(LIBC_SCCS) && !defined(lint)
37 static char *rcsid = "$OpenBSD: bindresvport.c,v 1.13 2000/01/26 03:43:21 deraadt Exp $";
38 #endif /* LIBC_SCCS and not lint */
39 
40 /*
41  * Copyright (c) 1987 by Sun Microsystems, Inc.
42  *
43  * Portions Copyright(C) 1996, Jason Downs.  All rights reserved.
44  */
45 
46 #include "includes.h"
47 
48 #define STARTPORT 600
49 #define ENDPORT (IPPORT_RESERVED - 1)
50 #define NPORTS	(ENDPORT - STARTPORT + 1)
51 
52 /*
53  * Bind a socket to a privileged IP port
54  */
55 int
56 bindresvport_sa(sd, sa)
57 	int sd;
58 	struct sockaddr *sa;
59 {
60 	int error, af;
61 	struct sockaddr_storage myaddr;
62 	struct sockaddr_in *sin;
63 	struct sockaddr_in6 *sin6;
64 	u_int16_t *portp;
65 	u_int16_t port;
66 	socklen_t salen;
67 	int i;
68 
69 	if (sa == NULL) {
70 		memset(&myaddr, 0, sizeof(myaddr));
71 		sa = (struct sockaddr *)&myaddr;
72 
73 		if (getsockname(sd, sa, &salen) == -1)
74 			return -1;	/* errno is correctly set */
75 
76 		af = sa->sa_family;
77 		memset(&myaddr, 0, salen);
78 	} else
79 		af = sa->sa_family;
80 
81 	if (af == AF_INET) {
82 		/* LINTED */
83 		sin = (struct sockaddr_in *)sa;
84 		salen = sizeof(struct sockaddr_in);
85 		portp = &sin->sin_port;
86 	} else if (af == AF_INET6) {
87 		/* LINTED */
88 		sin6 = (struct sockaddr_in6 *)sa;
89 		salen = sizeof(struct sockaddr_in6);
90 		portp = &sin6->sin6_port;
91 	} else {
92 		errno = EPFNOSUPPORT;
93 		return (-1);
94 	}
95 	sa->sa_family = af;
96 
97 	port = ntohs(*portp);
98 	if (port == 0)
99 		port = (arc4random() % NPORTS) + STARTPORT;
100 
101 	/* Avoid warning */
102 	error = -1;
103 
104 	for(i = 0; i < NPORTS; i++) {
105 		*portp = htons(port);
106 
107 		error = bind(sd, sa, salen);
108 
109 		/* Terminate on success */
110 		if (error == 0)
111 			break;
112 
113 		/* Terminate on errors, except "address already in use" */
114 		if ((error < 0) && !((errno == EADDRINUSE) || (errno == EINVAL)))
115 			break;
116 
117 		port++;
118 		if (port > ENDPORT)
119 			port = STARTPORT;
120 	}
121 
122 	return (error);
123 }
124 
125 #endif /* HAVE_BINDRESVPORT_SA */
126 
127 #pragma ident	"%Z%%M%	%I%	%E% SMI"
128