1 /* $OpenBSD: msg.c,v 1.18 2020/01/22 04:49:16 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
44 int
ssh_msg_send(int fd,u_char type,struct sshbuf * m)45 ssh_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("%s: type %u", __func__, (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("%s: write: %s", __func__, strerror(errno));
56 return (-1);
57 }
58 if (atomicio(vwrite, fd, sshbuf_mutable_ptr(m), mlen) != mlen) {
59 error("%s: write: %s", __func__, strerror(errno));
60 return (-1);
61 }
62 return (0);
63 }
64
65 int
ssh_msg_recv(int fd,struct sshbuf * m)66 ssh_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("%s: read header: %s", __func__, strerror(errno));
77 return (-1);
78 }
79 msg_len = get_u32(buf);
80 if (msg_len > 256 * 1024) {
81 error("%s: read: bad msg_len %u", __func__, 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("%s: read: %s", __func__, strerror(errno));
91 return (-1);
92 }
93 return (0);
94 }
95