1 /* $OpenBSD: msg.c,v 1.21 2024/05/17 00:30:24 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 <sys/types.h>
27 #include <sys/uio.h>
28
29 #include <errno.h>
30 #include <stdio.h>
31 #include <string.h>
32 #include <unistd.h>
33 #include <stdarg.h>
34
35 #include "sshbuf.h"
36 #include "ssherr.h"
37 #include "log.h"
38 #include "atomicio.h"
39 #include "msg.h"
40 #include "misc.h"
41
42 int
ssh_msg_send(int fd,u_char type,struct sshbuf * m)43 ssh_msg_send(int fd, u_char type, struct sshbuf *m)
44 {
45 u_char buf[5];
46 u_int mlen = sshbuf_len(m);
47
48 debug3_f("type %u len %zu", (unsigned int)type & 0xff, sshbuf_len(m));
49
50 put_u32(buf, mlen + 1);
51 buf[4] = type; /* 1st byte of payload is mesg-type */
52 if (atomicio(vwrite, fd, buf, sizeof(buf)) != sizeof(buf)) {
53 error_f("write: %s", strerror(errno));
54 return (-1);
55 }
56 if (atomicio(vwrite, fd, sshbuf_mutable_ptr(m), mlen) != mlen) {
57 error_f("write: %s", strerror(errno));
58 return (-1);
59 }
60 debug3_f("done");
61 return (0);
62 }
63
64 int
ssh_msg_recv(int fd,struct sshbuf * m)65 ssh_msg_recv(int fd, struct sshbuf *m)
66 {
67 u_char buf[4], *p;
68 u_int msg_len;
69 int r;
70
71 debug3("ssh_msg_recv entering");
72
73 if (atomicio(read, fd, buf, sizeof(buf)) != sizeof(buf)) {
74 if (errno != EPIPE)
75 error_f("read header: %s", strerror(errno));
76 return (-1);
77 }
78 msg_len = get_u32(buf);
79 if (msg_len > sshbuf_max_size(m)) {
80 error_f("read: bad msg_len %u", msg_len);
81 return (-1);
82 }
83 sshbuf_reset(m);
84 if ((r = sshbuf_reserve(m, msg_len, &p)) != 0) {
85 error_fr(r, "reserve");
86 return -1;
87 }
88 if (atomicio(read, fd, p, msg_len) != msg_len) {
89 error_f("read: %s", strerror(errno));
90 return (-1);
91 }
92 return (0);
93 }
94