msg.c revision 295367 
1/* $OpenBSD: msg.c,v 1.16 2015/01/15 09:40:00 djm Exp $ */
2/*
3 * Copyright (c) 2002 Markus Friedl.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "includes.h"
27
28#include <sys/types.h>
29#include <sys/uio.h>
30
31#include <errno.h>
32#include <stdio.h>
33#include <string.h>
34#include <unistd.h>
35#include <stdarg.h>
36
37#include "sshbuf.h"
38#include "ssherr.h"
39#include "log.h"
40#include "atomicio.h"
41#include "msg.h"
42#include "misc.h"
43
44int
45ssh_msg_send(int fd, u_char type, struct sshbuf *m)
46{
47	u_char buf[5];
48	u_int mlen = sshbuf_len(m);
49
50	debug3("ssh_msg_send: type %u", (unsigned int)type & 0xff);
51
52	put_u32(buf, mlen + 1);
53	buf[4] = type;		/* 1st byte of payload is mesg-type */
54	if (atomicio(vwrite, fd, buf, sizeof(buf)) != sizeof(buf)) {
55		error("ssh_msg_send: write");
56		return (-1);
57	}
58	if (atomicio(vwrite, fd, (u_char *)sshbuf_ptr(m), mlen) != mlen) {
59		error("ssh_msg_send: write");
60		return (-1);
61	}
62	return (0);
63}
64
65int
66ssh_msg_recv(int fd, struct sshbuf *m)
67{
68	u_char buf[4], *p;
69	u_int msg_len;
70	int r;
71
72	debug3("ssh_msg_recv entering");
73
74	if (atomicio(read, fd, buf, sizeof(buf)) != sizeof(buf)) {
75		if (errno != EPIPE)
76			error("ssh_msg_recv: read: header");
77		return (-1);
78	}
79	msg_len = get_u32(buf);
80	if (msg_len > 256 * 1024) {
81		error("ssh_msg_recv: read: bad msg_len %u", msg_len);
82		return (-1);
83	}
84	sshbuf_reset(m);
85	if ((r = sshbuf_reserve(m, msg_len, &p)) != 0) {
86		error("%s: buffer error: %s", __func__, ssh_err(r));
87		return -1;
88	}
89	if (atomicio(read, fd, p, msg_len) != msg_len) {
90		error("ssh_msg_recv: read: %s", strerror(errno));
91		return (-1);
92	}
93	return (0);
94}
95