1 /* $OpenBSD: dispatch.c,v 1.27 2015/05/01 07:10:01 djm Exp $ */
2 /*
3 * Copyright (c) 2000 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
30 #include <signal.h>
31 #include <stdarg.h>
32
33 #include "ssh1.h"
34 #include "ssh2.h"
35 #include "log.h"
36 #include "dispatch.h"
37 #include "packet.h"
38 #include "compat.h"
39 #include "ssherr.h"
40
41 int
dispatch_protocol_error(int type,u_int32_t seq,void * ctx)42 dispatch_protocol_error(int type, u_int32_t seq, void *ctx)
43 {
44 struct ssh *ssh = active_state; /* XXX */
45 int r;
46
47 logit("dispatch_protocol_error: type %d seq %u", type, seq);
48 if (!compat20)
49 fatal("protocol error");
50 if ((r = sshpkt_start(ssh, SSH2_MSG_UNIMPLEMENTED)) != 0 ||
51 (r = sshpkt_put_u32(ssh, seq)) != 0 ||
52 (r = sshpkt_send(ssh)) != 0 ||
53 (r = ssh_packet_write_wait(ssh)) != 0)
54 sshpkt_fatal(ssh, __func__, r);
55 return 0;
56 }
57
58 int
dispatch_protocol_ignore(int type,u_int32_t seq,void * ssh)59 dispatch_protocol_ignore(int type, u_int32_t seq, void *ssh)
60 {
61 logit("dispatch_protocol_ignore: type %d seq %u", type, seq);
62 return 0;
63 }
64
65 void
ssh_dispatch_init(struct ssh * ssh,dispatch_fn * dflt)66 ssh_dispatch_init(struct ssh *ssh, dispatch_fn *dflt)
67 {
68 u_int i;
69 for (i = 0; i < DISPATCH_MAX; i++)
70 ssh->dispatch[i] = dflt;
71 }
72
73 void
ssh_dispatch_range(struct ssh * ssh,u_int from,u_int to,dispatch_fn * fn)74 ssh_dispatch_range(struct ssh *ssh, u_int from, u_int to, dispatch_fn *fn)
75 {
76 u_int i;
77
78 for (i = from; i <= to; i++) {
79 if (i >= DISPATCH_MAX)
80 break;
81 ssh->dispatch[i] = fn;
82 }
83 }
84
85 void
ssh_dispatch_set(struct ssh * ssh,int type,dispatch_fn * fn)86 ssh_dispatch_set(struct ssh *ssh, int type, dispatch_fn *fn)
87 {
88 ssh->dispatch[type] = fn;
89 }
90
91 int
ssh_dispatch_run(struct ssh * ssh,int mode,volatile sig_atomic_t * done,void * ctxt)92 ssh_dispatch_run(struct ssh *ssh, int mode, volatile sig_atomic_t *done,
93 void *ctxt)
94 {
95 int r;
96 u_char type;
97 u_int32_t seqnr;
98
99 for (;;) {
100 if (mode == DISPATCH_BLOCK) {
101 r = ssh_packet_read_seqnr(ssh, &type, &seqnr);
102 if (r != 0)
103 return r;
104 } else {
105 r = ssh_packet_read_poll_seqnr(ssh, &type, &seqnr);
106 if (r != 0)
107 return r;
108 if (type == SSH_MSG_NONE)
109 return 0;
110 }
111 if (type > 0 && type < DISPATCH_MAX &&
112 ssh->dispatch[type] != NULL) {
113 if (ssh->dispatch_skip_packets) {
114 debug2("skipped packet (type %u)", type);
115 ssh->dispatch_skip_packets--;
116 continue;
117 }
118 /* XXX 'ssh' will replace 'ctxt' later */
119 r = (*ssh->dispatch[type])(type, seqnr, ctxt);
120 if (r != 0)
121 return r;
122 } else {
123 r = sshpkt_disconnect(ssh,
124 "protocol error: rcvd type %d", type);
125 if (r != 0)
126 return r;
127 return SSH_ERR_DISCONNECTED;
128 }
129 if (done != NULL && *done)
130 return 0;
131 }
132 }
133
134 void
ssh_dispatch_run_fatal(struct ssh * ssh,int mode,volatile sig_atomic_t * done,void * ctxt)135 ssh_dispatch_run_fatal(struct ssh *ssh, int mode, volatile sig_atomic_t *done,
136 void *ctxt)
137 {
138 int r;
139
140 if ((r = ssh_dispatch_run(ssh, mode, done, ctxt)) != 0)
141 sshpkt_fatal(ssh, __func__, r);
142 }
143