xref: /netbsd-src/crypto/external/bsd/openssh/dist/msg.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: msg.c,v 1.9 2020/02/27 00:24:40 christos Exp $	*/
2 /* $OpenBSD: msg.c,v 1.18 2020/01/22 04:49:16 djm Exp $ */
3 
4 /*
5  * Copyright (c) 2002 Markus Friedl.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
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.
15  *
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.
26  */
27 
28 #include "includes.h"
29 __RCSID("$NetBSD: msg.c,v 1.9 2020/02/27 00:24:40 christos Exp $");
30 #include <sys/types.h>
31 #include <sys/uio.h>
32 
33 #include <errno.h>
34 #include <stdio.h>
35 #include <string.h>
36 #include <unistd.h>
37 #include <stdarg.h>
38 #include <time.h>
39 
40 #include "sshbuf.h"
41 #include "ssherr.h"
42 #include "log.h"
43 #include "atomicio.h"
44 #include "msg.h"
45 #include "misc.h"
46 
47 int
48 ssh_msg_send(int fd, u_char type, struct sshbuf *m)
49 {
50 	u_char buf[5];
51 	u_int mlen = sshbuf_len(m);
52 
53 	debug3("%s: type %u", __func__, (unsigned int)type & 0xff);
54 
55 	put_u32(buf, mlen + 1);
56 	buf[4] = type;		/* 1st byte of payload is mesg-type */
57 	if (atomicio(vwrite, fd, buf, sizeof(buf)) != sizeof(buf)) {
58 		error("%s: write: %s", __func__, strerror(errno));
59 		return (-1);
60 	}
61 	if (atomicio(vwrite, fd, sshbuf_mutable_ptr(m), mlen) != mlen) {
62 		error("%s: write: %s", __func__, strerror(errno));
63 		return (-1);
64 	}
65 	return (0);
66 }
67 
68 int
69 ssh_msg_recv(int fd, struct sshbuf *m)
70 {
71 	u_char buf[4], *p;
72 	u_int msg_len;
73 	int r;
74 
75 	debug3("ssh_msg_recv entering");
76 
77 	if (atomicio(read, fd, buf, sizeof(buf)) != sizeof(buf)) {
78 		if (errno != EPIPE)
79 			error("%s: read header: %s", __func__, strerror(errno));
80 		return (-1);
81 	}
82 	msg_len = get_u32(buf);
83 	if (msg_len > 256 * 1024) {
84 		error("%s: read: bad msg_len %u", __func__, msg_len);
85 		return (-1);
86 	}
87 	sshbuf_reset(m);
88 	if ((r = sshbuf_reserve(m, msg_len, &p)) != 0) {
89 		error("%s: buffer error: %s", __func__, ssh_err(r));
90 		return -1;
91 	}
92 	if (atomicio(read, fd, p, msg_len) != msg_len) {
93 		error("%s: read: %s", __func__, strerror(errno));
94 		return (-1);
95 	}
96 	return (0);
97 }
98