msg.c revision 124208
1/*
2 * Copyright (c) 2002 Markus Friedl.  All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24#include "includes.h"
25RCSID("$OpenBSD: msg.c,v 1.6 2003/06/28 16:23:06 deraadt Exp $");
26
27#include "buffer.h"
28#include "getput.h"
29#include "log.h"
30#include "atomicio.h"
31#include "msg.h"
32
33void
34ssh_msg_send(int fd, u_char type, Buffer *m)
35{
36	u_char buf[5];
37	u_int mlen = buffer_len(m);
38
39	debug3("ssh_msg_send: type %u", (unsigned int)type & 0xff);
40
41	PUT_32BIT(buf, mlen + 1);
42	buf[4] = type;		/* 1st byte of payload is mesg-type */
43	if (atomicio(vwrite, fd, buf, sizeof(buf)) != sizeof(buf))
44		fatal("ssh_msg_send: write");
45	if (atomicio(vwrite, fd, buffer_ptr(m), mlen) != mlen)
46		fatal("ssh_msg_send: write");
47}
48
49int
50ssh_msg_recv(int fd, Buffer *m)
51{
52	u_char buf[4];
53	ssize_t res;
54	u_int msg_len;
55
56	debug3("ssh_msg_recv entering");
57
58	res = atomicio(read, fd, buf, sizeof(buf));
59	if (res != sizeof(buf)) {
60		if (res == 0)
61			return -1;
62		fatal("ssh_msg_recv: read: header %ld", (long)res);
63	}
64	msg_len = GET_32BIT(buf);
65	if (msg_len > 256 * 1024)
66		fatal("ssh_msg_recv: read: bad msg_len %u", msg_len);
67	buffer_clear(m);
68	buffer_append_space(m, msg_len);
69	res = atomicio(read, fd, buffer_ptr(m), msg_len);
70	if (res != msg_len)
71		fatal("ssh_msg_recv: read: %ld != msg_len", (long)res);
72	return 0;
73}
74