xref: /netbsd-src/crypto/external/bsd/openssh/dist/msg.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: msg.c,v 1.4 2015/04/03 23:58:19 christos Exp $	*/
2 /* $OpenBSD: msg.c,v 1.16 2015/01/15 09:40:00 djm Exp $ */
3 /*
4  * Copyright (c) 2002 Markus Friedl.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include "includes.h"
28 __RCSID("$NetBSD: msg.c,v 1.4 2015/04/03 23:58:19 christos Exp $");
29 #include <sys/types.h>
30 #include <sys/uio.h>
31 
32 #include <errno.h>
33 #include <stdio.h>
34 #include <string.h>
35 #include <unistd.h>
36 #include <stdarg.h>
37 #include <time.h>
38 
39 #include "sshbuf.h"
40 #include "ssherr.h"
41 #include "log.h"
42 #include "atomicio.h"
43 #include "msg.h"
44 #include "misc.h"
45 
46 int
47 ssh_msg_send(int fd, u_char type, struct sshbuf *m)
48 {
49 	u_char buf[5];
50 	u_int mlen = sshbuf_len(m);
51 
52 	debug3("ssh_msg_send: type %u", (unsigned int)type & 0xff);
53 
54 	put_u32(buf, mlen + 1);
55 	buf[4] = type;		/* 1st byte of payload is mesg-type */
56 	if (atomicio(vwrite, fd, buf, sizeof(buf)) != sizeof(buf)) {
57 		error("ssh_msg_send: write");
58 		return (-1);
59 	}
60 	if (atomicio(vwrite, fd, __UNCONST(sshbuf_ptr(m)), mlen) != mlen) {
61 		error("ssh_msg_send: write");
62 		return (-1);
63 	}
64 	return (0);
65 }
66 
67 int
68 ssh_msg_recv(int fd, struct sshbuf *m)
69 {
70 	u_char buf[4], *p;
71 	u_int msg_len;
72 	int r;
73 
74 	debug3("ssh_msg_recv entering");
75 
76 	if (atomicio(read, fd, buf, sizeof(buf)) != sizeof(buf)) {
77 		if (errno != EPIPE)
78 			error("ssh_msg_recv: read: header");
79 		return (-1);
80 	}
81 	msg_len = get_u32(buf);
82 	if (msg_len > 256 * 1024) {
83 		error("ssh_msg_recv: read: bad msg_len %u", msg_len);
84 		return (-1);
85 	}
86 	sshbuf_reset(m);
87 	if ((r = sshbuf_reserve(m, msg_len, &p)) != 0) {
88 		error("%s: buffer error: %s", __func__, ssh_err(r));
89 		return -1;
90 	}
91 	if (atomicio(read, fd, p, msg_len) != msg_len) {
92 		error("ssh_msg_recv: read: %s", strerror(errno));
93 		return (-1);
94 	}
95 	return (0);
96 }
97