1 /* $NetBSD: fdpass.c,v 1.1 2012/08/13 11:15:05 christos Exp $ */
2 /* $OpenBSD: monitor_fdpass.c,v 1.19 2010/01/12 00:58:25 djm Exp $ */
4 * Copyright 2001 Niels Provos <provos@citi.umich.edu>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 #include <sys/cdefs.h>
29 __RCSID("$NetBSD: fdpass.c,v 1.1 2012/08/13 11:15:05 christos Exp $");
30 #include <sys/types.h>
31 #include <sys/socket.h>
47 send_fd(int sock
, int fd
)
60 if (sizeof(cmsgbuf
.buf
) < CMSG_SPACE(sizeof(int)))
61 errx(1, "%s: %zu < %zu, recompile", __func__
,
62 sizeof(cmsgbuf
.buf
), CMSG_SPACE(sizeof(int)));
64 memset(&msg
, 0, sizeof(msg
));
65 msg
.msg_control
= &cmsgbuf
.buf
;
66 msg
.msg_controllen
= CMSG_SPACE(sizeof(int));
67 cmsg
= CMSG_FIRSTHDR(&msg
);
68 cmsg
->cmsg_len
= CMSG_LEN(sizeof(int));
69 cmsg
->cmsg_level
= SOL_SOCKET
;
70 cmsg
->cmsg_type
= SCM_RIGHTS
;
71 *(int *)CMSG_DATA(cmsg
) = fd
;
72 msg
.msg_controllen
= cmsg
->cmsg_len
;
81 while ((n
= sendmsg(sock
, &msg
, 0)) == -1 &&
82 (errno
== EAGAIN
|| errno
== EINTR
)) {
83 (void)poll(&pfd
, 1, -1);
87 err(1, "%s: sendmsg(%d)", __func__
, fd
);
90 fprintf(stderr
, "%d: send fd %d\n", getpid(), fd
);
93 errx(1, "%s: sendmsg: expected sent 1 got %ld",
106 struct cmsghdr
*cmsg
;
113 if (sizeof(cmsgbuf
.buf
) < CMSG_SPACE(sizeof(int)))
114 errx(1, "%s: %zu < %zu, recompile", __func__
,
115 sizeof(cmsgbuf
.buf
), CMSG_SPACE(sizeof(int)));
117 memset(&msg
, 0, sizeof(msg
));
122 msg
.msg_control
= &cmsgbuf
.buf
;
123 msg
.msg_controllen
= CMSG_SPACE(sizeof(int));
127 while ((n
= recvmsg(sock
, &msg
, 0)) == -1 &&
128 (errno
== EAGAIN
|| errno
== EINTR
)) {
129 (void)poll(&pfd
, 1, -1);
133 err(1, "%s: recvmsg", __func__
);
137 errx(1, "%s: recvmsg: expected received 1 got %ld",
141 cmsg
= CMSG_FIRSTHDR(&msg
);
143 errx(1, "%s: no message header", __func__
);
145 if (cmsg
->cmsg_type
!= SCM_RIGHTS
)
146 err(1, "%s: expected type %d got %d", __func__
,
147 SCM_RIGHTS
, cmsg
->cmsg_type
);
148 fd
= (*(int *)CMSG_DATA(cmsg
));
150 fprintf(stderr
, "%d: recv fd %d\n", getpid(), fd
);
154 static void usage(void) __attribute__((__noreturn__
));
159 fprintf(stderr
, "Usage: %s [-vd] -i <input> -o <output>\n"
160 "\t %s [-v] -p <progname>\n", getprogname(), getprogname());
165 main(int argc
, char *argv
[])
167 int s
[2], fd
, status
, c
, verbose
;
168 char buf
[1024], *prog
;
174 while ((c
= getopt(argc
, argv
, "di:o:p:")) != -1)
192 if ((s
[0] == -1 && s
[1] != -1) || (s
[0] != -1 && s
[1] == -1))
196 if (socketpair(AF_LOCAL
, SOCK_DGRAM
, 0, s
) == -1)
197 err(1, "socketpair");
205 fd
= open("foo", O_RDWR
|O_CREAT
|O_TRUNC
, 0666);
214 snprintf(i
, sizeof(i
), "%d", s
[0]);
215 snprintf(o
, sizeof(o
), "%d", s
[1]);
216 execlp(prog
, prog
, "-i", i
, "-o", o
, NULL
);
222 snprintf(buf
, sizeof(buf
), "ls -l /proc/%d/fd",
226 if (write(fd
, "foo\n", 4) == -1)