1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 1987 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #pragma ident "%Z%%M% %I% %E% SMI"
28
29 #include <sys/types.h>
30 #include <errno.h>
31 #include <sys/socket.h>
32 #include <netinet/in.h>
33
34 /*
35 * Bind a socket to a privileged IP port
36 */
37 int
bindresvport(int sd,struct sockaddr_in * sin)38 bindresvport(int sd, struct sockaddr_in *sin)
39 {
40 int res;
41 static short port;
42 struct sockaddr_in myaddr;
43 int i;
44
45 #define STARTPORT 600
46 #define ENDPORT (IPPORT_RESERVED - 1)
47 #define NPORTS (ENDPORT - STARTPORT + 1)
48
49 if (sin == (struct sockaddr_in *)0) {
50 sin = &myaddr;
51 bzero(sin, sizeof (*sin));
52 sin->sin_family = AF_INET;
53 } else if (sin->sin_family != AF_INET) {
54 errno = EPFNOSUPPORT;
55 return (-1);
56 }
57 if (port == 0) {
58 port = (getpid() % NPORTS) + STARTPORT;
59 }
60 res = -1;
61 errno = EADDRINUSE;
62 for (i = 0; i < NPORTS && res < 0 && errno == EADDRINUSE; i++) {
63 sin->sin_port = htons(port++);
64 if (port > ENDPORT) {
65 port = STARTPORT;
66 }
67 res = bind(sd, sin, sizeof(struct sockaddr_in));
68 }
69 return (res);
70 }
71