1 /* $NetBSD: sockpair.c,v 1.3 2021/08/14 16:14:58 christos Exp $ */
2
3 /* $OpenLDAP$ */
4 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
5 *
6 * Copyright 1998-2021 The OpenLDAP Foundation.
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted only as authorized by the OpenLDAP
11 * Public License.
12 *
13 * A copy of this license is available in the file LICENSE in the
14 * top-level directory of the distribution or, alternatively, at
15 * <http://www.OpenLDAP.org/license.html>.
16 */
17
18 #include <sys/cdefs.h>
19 __RCSID("$NetBSD: sockpair.c,v 1.3 2021/08/14 16:14:58 christos Exp $");
20
21 #include "portable.h"
22 #include <ac/socket.h>
23 #include <ac/unistd.h>
24
25 #include <lutil.h>
26
27 /* Return a pair of socket descriptors that are connected to each other.
28 * The returned descriptors are suitable for use with select(). The two
29 * descriptors may or may not be identical; the function may return
30 * the same descriptor number in both slots. It is guaranteed that
31 * data written on sds[1] will be readable on sds[0]. The returned
32 * descriptors may be datagram oriented, so data should be written
33 * in reasonably small pieces and read all at once. On Unix systems
34 * this function is best implemented using a single pipe() call.
35 */
36
lutil_pair(ber_socket_t sds[2])37 int lutil_pair( ber_socket_t sds[2] )
38 {
39 #ifdef USE_PIPE
40 return pipe( sds );
41 #else
42 struct sockaddr_in si;
43 int rc;
44 ber_socklen_t len = sizeof(si);
45 ber_socket_t sd;
46
47 sd = socket( AF_INET, SOCK_DGRAM, 0 );
48 if ( sd == AC_SOCKET_INVALID ) {
49 return sd;
50 }
51
52 (void) memset( (void*) &si, '\0', len );
53 si.sin_family = AF_INET;
54 si.sin_port = 0;
55 si.sin_addr.s_addr = htonl( INADDR_LOOPBACK );
56
57 rc = bind( sd, (struct sockaddr *)&si, len );
58 if ( rc == AC_SOCKET_ERROR ) {
59 tcp_close(sd);
60 return rc;
61 }
62
63 rc = getsockname( sd, (struct sockaddr *)&si, &len );
64 if ( rc == AC_SOCKET_ERROR ) {
65 tcp_close(sd);
66 return rc;
67 }
68
69 rc = connect( sd, (struct sockaddr *)&si, len );
70 if ( rc == AC_SOCKET_ERROR ) {
71 tcp_close(sd);
72 return rc;
73 }
74
75 sds[0] = sd;
76 #if !HAVE_WINSOCK
77 sds[1] = dup( sds[0] );
78 #else
79 sds[1] = sds[0];
80 #endif
81 return 0;
82 #endif
83 }
84