1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1 |
/* $OpenBSD: packet.c,v 1.157 2008/07/10 18:08:11 markus Exp $ */
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
2 |
/*
|
3 |
* Author: Tatu Ylonen <ylo@cs.hut.fi>
|
|
4 |
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
|
|
5 |
* All rights reserved
|
|
6 |
* This file contains code implementing the packet protocol and communication
|
|
7 |
* with the other side. This same code is used both on client and server side.
|
|
8 |
*
|
|
9 |
* As far as I am concerned, the code I have written for this software
|
|
10 |
* can be used freely for any purpose. Any derived versions of this
|
|
11 |
* software must be clearly marked as such, and if the derived work is
|
|
12 |
* incompatible with the protocol description in the RFC file, it must be
|
|
13 |
* called by a name other than "ssh" or "Secure Shell".
|
|
14 |
*
|
|
15 |
*
|
|
16 |
* SSH2 packet format added by Markus Friedl.
|
|
17 |
* Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
|
|
18 |
*
|
|
19 |
* Redistribution and use in source and binary forms, with or without
|
|
20 |
* modification, are permitted provided that the following conditions
|
|
21 |
* are met:
|
|
22 |
* 1. Redistributions of source code must retain the above copyright
|
|
23 |
* notice, this list of conditions and the following disclaimer.
|
|
24 |
* 2. Redistributions in binary form must reproduce the above copyright
|
|
25 |
* notice, this list of conditions and the following disclaimer in the
|
|
26 |
* documentation and/or other materials provided with the distribution.
|
|
27 |
*
|
|
28 |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
29 |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
30 |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
31 |
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
32 |
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
|
33 |
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
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34 |
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
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35 |
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
36 |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|
37 |
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
38 |
*/
|
|
39 |
||
40 |
#include "includes.h" |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
41 |
|
42 |
#include <sys/types.h> |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
43 |
#include "openbsd-compat/sys-queue.h" |
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
44 |
#include <sys/param.h> |
45 |
#include <sys/socket.h> |
|
46 |
#ifdef HAVE_SYS_TIME_H
|
|
47 |
# include <sys/time.h>
|
|
48 |
#endif
|
|
49 |
||
50 |
#include <netinet/in.h> |
|
51 |
#include <netinet/ip.h> |
|
52 |
#include <arpa/inet.h> |
|
53 |
||
54 |
#include <errno.h> |
|
55 |
#include <stdarg.h> |
|
56 |
#include <stdio.h> |
|
57 |
#include <stdlib.h> |
|
58 |
#include <string.h> |
|
59 |
#include <unistd.h> |
|
60 |
#include <signal.h> |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
61 |
|
62 |
#include "xmalloc.h" |
|
63 |
#include "buffer.h" |
|
64 |
#include "packet.h" |
|
65 |
#include "crc32.h" |
|
66 |
#include "compress.h" |
|
67 |
#include "deattack.h" |
|
68 |
#include "channels.h" |
|
69 |
#include "compat.h" |
|
70 |
#include "ssh1.h" |
|
71 |
#include "ssh2.h" |
|
72 |
#include "cipher.h" |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
73 |
#include "key.h" |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
74 |
#include "kex.h" |
75 |
#include "mac.h" |
|
76 |
#include "log.h" |
|
77 |
#include "canohost.h" |
|
78 |
#include "misc.h" |
|
79 |
#include "ssh.h" |
|
80 |
||
81 |
#ifdef PACKET_DEBUG
|
|
82 |
#define DBG(x) x
|
|
83 |
#else
|
|
84 |
#define DBG(x)
|
|
85 |
#endif
|
|
86 |
||
87 |
/*
|
|
88 |
* This variable contains the file descriptors used for communicating with
|
|
89 |
* the other side. connection_in is used for reading; connection_out for
|
|
90 |
* writing. These can be the same descriptor, in which case it is assumed to
|
|
91 |
* be a socket.
|
|
92 |
*/
|
|
93 |
static int connection_in = -1; |
|
94 |
static int connection_out = -1; |
|
95 |
||
96 |
/* Protocol flags for the remote side. */
|
|
97 |
static u_int remote_protocol_flags = 0; |
|
98 |
||
99 |
/* Encryption context for receiving data. This is only used for decryption. */
|
|
100 |
static CipherContext receive_context; |
|
101 |
||
102 |
/* Encryption context for sending data. This is only used for encryption. */
|
|
103 |
static CipherContext send_context; |
|
104 |
||
105 |
/* Buffer for raw input data from the socket. */
|
|
106 |
Buffer input; |
|
107 |
||
108 |
/* Buffer for raw output data going to the socket. */
|
|
109 |
Buffer output; |
|
110 |
||
111 |
/* Buffer for the partial outgoing packet being constructed. */
|
|
112 |
static Buffer outgoing_packet; |
|
113 |
||
114 |
/* Buffer for the incoming packet currently being processed. */
|
|
115 |
static Buffer incoming_packet; |
|
116 |
||
117 |
/* Scratch buffer for packet compression/decompression. */
|
|
118 |
static Buffer compression_buffer; |
|
119 |
static int compression_buffer_ready = 0; |
|
120 |
||
121 |
/* Flag indicating whether packet compression/decompression is enabled. */
|
|
122 |
static int packet_compression = 0; |
|
123 |
||
124 |
/* default maximum packet size */
|
|
125 |
u_int max_packet_size = 32768; |
|
126 |
||
127 |
/* Flag indicating whether this module has been initialized. */
|
|
128 |
static int initialized = 0; |
|
129 |
||
130 |
/* Set to true if the connection is interactive. */
|
|
131 |
static int interactive_mode = 0; |
|
132 |
||
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
133 |
/* Set to true if we are the server side. */
|
134 |
static int server_side = 0; |
|
135 |
||
136 |
/* Set to true if we are authenticated. */
|
|
137 |
static int after_authentication = 0; |
|
138 |
||
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
139 |
int keep_alive_timeouts = 0; |
140 |
||
141 |
/* Set to the maximum time that we will wait to send or receive a packet */
|
|
142 |
static int packet_timeout_ms = -1; |
|
143 |
||
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
144 |
/* Session key information for Encryption and MAC */
|
145 |
Newkeys *newkeys[MODE_MAX]; |
|
146 |
static struct packet_state { |
|
147 |
u_int32_t seqnr; |
|
148 |
u_int32_t packets; |
|
149 |
u_int64_t blocks; |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
150 |
u_int64_t bytes; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
151 |
} p_read, p_send; |
152 |
||
153 |
static u_int64_t max_blocks_in, max_blocks_out; |
|
154 |
static u_int32_t rekey_limit; |
|
155 |
||
156 |
/* Session key for protocol v1 */
|
|
157 |
static u_char ssh1_key[SSH_SESSION_KEY_LENGTH]; |
|
158 |
static u_int ssh1_keylen; |
|
159 |
||
160 |
/* roundup current message to extra_pad bytes */
|
|
161 |
static u_char extra_pad = 0; |
|
162 |
||
163 |
struct packet { |
|
164 |
TAILQ_ENTRY(packet) next; |
|
165 |
u_char type; |
|
166 |
Buffer payload; |
|
167 |
};
|
|
168 |
TAILQ_HEAD(, packet) outgoing; |
|
169 |
||
170 |
/*
|
|
171 |
* Sets the descriptors used for communication. Disables encryption until
|
|
172 |
* packet_set_encryption_key is called.
|
|
173 |
*/
|
|
174 |
void
|
|
175 |
packet_set_connection(int fd_in, int fd_out) |
|
176 |
{
|
|
177 |
Cipher *none = cipher_by_name("none"); |
|
178 |
||
179 |
if (none == NULL) |
|
180 |
fatal("packet_set_connection: cannot load cipher 'none'"); |
|
181 |
connection_in = fd_in; |
|
182 |
connection_out = fd_out; |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
183 |
cipher_init(&send_context, none, (const u_char *)"", |
184 |
0, NULL, 0, CIPHER_ENCRYPT); |
|
185 |
cipher_init(&receive_context, none, (const u_char *)"", |
|
186 |
0, NULL, 0, CIPHER_DECRYPT); |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
187 |
newkeys[MODE_IN] = newkeys[MODE_OUT] = NULL; |
188 |
if (!initialized) { |
|
189 |
initialized = 1; |
|
190 |
buffer_init(&input); |
|
191 |
buffer_init(&output); |
|
192 |
buffer_init(&outgoing_packet); |
|
193 |
buffer_init(&incoming_packet); |
|
194 |
TAILQ_INIT(&outgoing); |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
195 |
p_send.packets = p_read.packets = 0; |
196 |
}
|
|
197 |
}
|
|
198 |
||
199 |
void
|
|
200 |
packet_set_timeout(int timeout, int count) |
|
201 |
{
|
|
202 |
if (timeout == 0 || count == 0) { |
|
203 |
packet_timeout_ms = -1; |
|
204 |
return; |
|
205 |
}
|
|
206 |
if ((INT_MAX / 1000) / count < timeout) |
|
207 |
packet_timeout_ms = INT_MAX; |
|
208 |
else
|
|
209 |
packet_timeout_ms = timeout * count * 1000; |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
210 |
}
|
211 |
||
212 |
/* Returns 1 if remote host is connected via socket, 0 if not. */
|
|
213 |
||
214 |
int
|
|
215 |
packet_connection_is_on_socket(void) |
|
216 |
{
|
|
217 |
struct sockaddr_storage from, to; |
|
218 |
socklen_t fromlen, tolen; |
|
219 |
||
220 |
/* filedescriptors in and out are the same, so it's a socket */
|
|
221 |
if (connection_in == connection_out) |
|
222 |
return 1; |
|
223 |
fromlen = sizeof(from); |
|
224 |
memset(&from, 0, sizeof(from)); |
|
225 |
if (getpeername(connection_in, (struct sockaddr *)&from, &fromlen) < 0) |
|
226 |
return 0; |
|
227 |
tolen = sizeof(to); |
|
228 |
memset(&to, 0, sizeof(to)); |
|
229 |
if (getpeername(connection_out, (struct sockaddr *)&to, &tolen) < 0) |
|
230 |
return 0; |
|
231 |
if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0) |
|
232 |
return 0; |
|
233 |
if (from.ss_family != AF_INET && from.ss_family != AF_INET6) |
|
234 |
return 0; |
|
235 |
return 1; |
|
236 |
}
|
|
237 |
||
238 |
/*
|
|
239 |
* Exports an IV from the CipherContext required to export the key
|
|
240 |
* state back from the unprivileged child to the privileged parent
|
|
241 |
* process.
|
|
242 |
*/
|
|
243 |
||
244 |
void
|
|
245 |
packet_get_keyiv(int mode, u_char *iv, u_int len) |
|
246 |
{
|
|
247 |
CipherContext *cc; |
|
248 |
||
249 |
if (mode == MODE_OUT) |
|
250 |
cc = &send_context; |
|
251 |
else
|
|
252 |
cc = &receive_context; |
|
253 |
||
254 |
cipher_get_keyiv(cc, iv, len); |
|
255 |
}
|
|
256 |
||
257 |
int
|
|
258 |
packet_get_keycontext(int mode, u_char *dat) |
|
259 |
{
|
|
260 |
CipherContext *cc; |
|
261 |
||
262 |
if (mode == MODE_OUT) |
|
263 |
cc = &send_context; |
|
264 |
else
|
|
265 |
cc = &receive_context; |
|
266 |
||
267 |
return (cipher_get_keycontext(cc, dat)); |
|
268 |
}
|
|
269 |
||
270 |
void
|
|
271 |
packet_set_keycontext(int mode, u_char *dat) |
|
272 |
{
|
|
273 |
CipherContext *cc; |
|
274 |
||
275 |
if (mode == MODE_OUT) |
|
276 |
cc = &send_context; |
|
277 |
else
|
|
278 |
cc = &receive_context; |
|
279 |
||
280 |
cipher_set_keycontext(cc, dat); |
|
281 |
}
|
|
282 |
||
283 |
int
|
|
284 |
packet_get_keyiv_len(int mode) |
|
285 |
{
|
|
286 |
CipherContext *cc; |
|
287 |
||
288 |
if (mode == MODE_OUT) |
|
289 |
cc = &send_context; |
|
290 |
else
|
|
291 |
cc = &receive_context; |
|
292 |
||
293 |
return (cipher_get_keyiv_len(cc)); |
|
294 |
}
|
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
295 |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
296 |
void
|
297 |
packet_set_iv(int mode, u_char *dat) |
|
298 |
{
|
|
299 |
CipherContext *cc; |
|
300 |
||
301 |
if (mode == MODE_OUT) |
|
302 |
cc = &send_context; |
|
303 |
else
|
|
304 |
cc = &receive_context; |
|
305 |
||
306 |
cipher_set_keyiv(cc, dat); |
|
307 |
}
|
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
308 |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
309 |
int
|
310 |
packet_get_ssh1_cipher(void) |
|
311 |
{
|
|
312 |
return (cipher_get_number(receive_context.cipher)); |
|
313 |
}
|
|
314 |
||
315 |
void
|
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
316 |
packet_get_state(int mode, u_int32_t *seqnr, u_int64_t *blocks, u_int32_t *packets, |
317 |
u_int64_t *bytes) |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
318 |
{
|
319 |
struct packet_state *state; |
|
320 |
||
321 |
state = (mode == MODE_IN) ? &p_read : &p_send; |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
322 |
if (seqnr) |
323 |
*seqnr = state->seqnr; |
|
324 |
if (blocks) |
|
325 |
*blocks = state->blocks; |
|
326 |
if (packets) |
|
327 |
*packets = state->packets; |
|
328 |
if (bytes) |
|
329 |
*bytes = state->bytes; |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
330 |
}
|
331 |
||
332 |
void
|
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
333 |
packet_set_state(int mode, u_int32_t seqnr, u_int64_t blocks, u_int32_t packets, |
334 |
u_int64_t bytes) |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
335 |
{
|
336 |
struct packet_state *state; |
|
337 |
||
338 |
state = (mode == MODE_IN) ? &p_read : &p_send; |
|
339 |
state->seqnr = seqnr; |
|
340 |
state->blocks = blocks; |
|
341 |
state->packets = packets; |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
342 |
state->bytes = bytes; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
343 |
}
|
344 |
||
345 |
/* returns 1 if connection is via ipv4 */
|
|
346 |
||
347 |
int
|
|
348 |
packet_connection_is_ipv4(void) |
|
349 |
{
|
|
350 |
struct sockaddr_storage to; |
|
351 |
socklen_t tolen = sizeof(to); |
|
352 |
||
353 |
memset(&to, 0, sizeof(to)); |
|
354 |
if (getsockname(connection_out, (struct sockaddr *)&to, &tolen) < 0) |
|
355 |
return 0; |
|
356 |
if (to.ss_family == AF_INET) |
|
357 |
return 1; |
|
358 |
#ifdef IPV4_IN_IPV6
|
|
359 |
if (to.ss_family == AF_INET6 && |
|
360 |
IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr)) |
|
361 |
return 1; |
|
362 |
#endif
|
|
363 |
return 0; |
|
364 |
}
|
|
365 |
||
366 |
/* Sets the connection into non-blocking mode. */
|
|
367 |
||
368 |
void
|
|
369 |
packet_set_nonblocking(void) |
|
370 |
{
|
|
371 |
/* Set the socket into non-blocking mode. */
|
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
372 |
set_nonblock(connection_in); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
373 |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
374 |
if (connection_out != connection_in) |
375 |
set_nonblock(connection_out); |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
376 |
}
|
377 |
||
378 |
/* Returns the socket used for reading. */
|
|
379 |
||
380 |
int
|
|
381 |
packet_get_connection_in(void) |
|
382 |
{
|
|
383 |
return connection_in; |
|
384 |
}
|
|
385 |
||
386 |
/* Returns the descriptor used for writing. */
|
|
387 |
||
388 |
int
|
|
389 |
packet_get_connection_out(void) |
|
390 |
{
|
|
391 |
return connection_out; |
|
392 |
}
|
|
393 |
||
394 |
/* Closes the connection and clears and frees internal data structures. */
|
|
395 |
||
396 |
void
|
|
397 |
packet_close(void) |
|
398 |
{
|
|
399 |
if (!initialized) |
|
400 |
return; |
|
401 |
initialized = 0; |
|
402 |
if (connection_in == connection_out) { |
|
403 |
shutdown(connection_out, SHUT_RDWR); |
|
404 |
close(connection_out); |
|
405 |
} else { |
|
406 |
close(connection_in); |
|
407 |
close(connection_out); |
|
408 |
}
|
|
409 |
buffer_free(&input); |
|
410 |
buffer_free(&output); |
|
411 |
buffer_free(&outgoing_packet); |
|
412 |
buffer_free(&incoming_packet); |
|
413 |
if (compression_buffer_ready) { |
|
414 |
buffer_free(&compression_buffer); |
|
415 |
buffer_compress_uninit(); |
|
416 |
}
|
|
417 |
cipher_cleanup(&send_context); |
|
418 |
cipher_cleanup(&receive_context); |
|
419 |
}
|
|
420 |
||
421 |
/* Sets remote side protocol flags. */
|
|
422 |
||
423 |
void
|
|
424 |
packet_set_protocol_flags(u_int protocol_flags) |
|
425 |
{
|
|
426 |
remote_protocol_flags = protocol_flags; |
|
427 |
}
|
|
428 |
||
429 |
/* Returns the remote protocol flags set earlier by the above function. */
|
|
430 |
||
431 |
u_int
|
|
432 |
packet_get_protocol_flags(void) |
|
433 |
{
|
|
434 |
return remote_protocol_flags; |
|
435 |
}
|
|
436 |
||
437 |
/*
|
|
438 |
* Starts packet compression from the next packet on in both directions.
|
|
439 |
* Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
|
|
440 |
*/
|
|
441 |
||
442 |
static void |
|
443 |
packet_init_compression(void) |
|
444 |
{
|
|
445 |
if (compression_buffer_ready == 1) |
|
446 |
return; |
|
447 |
compression_buffer_ready = 1; |
|
448 |
buffer_init(&compression_buffer); |
|
449 |
}
|
|
450 |
||
451 |
void
|
|
452 |
packet_start_compression(int level) |
|
453 |
{
|
|
454 |
if (packet_compression && !compat20) |
|
455 |
fatal("Compression already enabled."); |
|
456 |
packet_compression = 1; |
|
457 |
packet_init_compression(); |
|
458 |
buffer_compress_init_send(level); |
|
459 |
buffer_compress_init_recv(); |
|
460 |
}
|
|
461 |
||
462 |
/*
|
|
463 |
* Causes any further packets to be encrypted using the given key. The same
|
|
464 |
* key is used for both sending and reception. However, both directions are
|
|
465 |
* encrypted independently of each other.
|
|
466 |
*/
|
|
467 |
||
468 |
void
|
|
469 |
packet_set_encryption_key(const u_char *key, u_int keylen, |
|
470 |
int number) |
|
471 |
{
|
|
472 |
Cipher *cipher = cipher_by_number(number); |
|
473 |
||
474 |
if (cipher == NULL) |
|
475 |
fatal("packet_set_encryption_key: unknown cipher number %d", number); |
|
476 |
if (keylen < 20) |
|
477 |
fatal("packet_set_encryption_key: keylen too small: %d", keylen); |
|
478 |
if (keylen > SSH_SESSION_KEY_LENGTH) |
|
479 |
fatal("packet_set_encryption_key: keylen too big: %d", keylen); |
|
480 |
memcpy(ssh1_key, key, keylen); |
|
481 |
ssh1_keylen = keylen; |
|
482 |
cipher_init(&send_context, cipher, key, keylen, NULL, 0, CIPHER_ENCRYPT); |
|
483 |
cipher_init(&receive_context, cipher, key, keylen, NULL, 0, CIPHER_DECRYPT); |
|
484 |
}
|
|
485 |
||
486 |
u_int
|
|
487 |
packet_get_encryption_key(u_char *key) |
|
488 |
{
|
|
489 |
if (key == NULL) |
|
490 |
return (ssh1_keylen); |
|
491 |
memcpy(key, ssh1_key, ssh1_keylen); |
|
492 |
return (ssh1_keylen); |
|
493 |
}
|
|
494 |
||
495 |
/* Start constructing a packet to send. */
|
|
496 |
void
|
|
497 |
packet_start(u_char type) |
|
498 |
{
|
|
499 |
u_char buf[9]; |
|
500 |
int len; |
|
501 |
||
502 |
DBG(debug("packet_start[%d]", type)); |
|
503 |
len = compat20 ? 6 : 9; |
|
504 |
memset(buf, 0, len - 1); |
|
505 |
buf[len - 1] = type; |
|
506 |
buffer_clear(&outgoing_packet); |
|
507 |
buffer_append(&outgoing_packet, buf, len); |
|
508 |
}
|
|
509 |
||
510 |
/* Append payload. */
|
|
511 |
void
|
|
512 |
packet_put_char(int value) |
|
513 |
{
|
|
514 |
char ch = value; |
|
515 |
||
516 |
buffer_append(&outgoing_packet, &ch, 1); |
|
517 |
}
|
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
518 |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
519 |
void
|
520 |
packet_put_int(u_int value) |
|
521 |
{
|
|
522 |
buffer_put_int(&outgoing_packet, value); |
|
523 |
}
|
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
524 |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
525 |
void
|
526 |
packet_put_string(const void *buf, u_int len) |
|
527 |
{
|
|
528 |
buffer_put_string(&outgoing_packet, buf, len); |
|
529 |
}
|
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
530 |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
531 |
void
|
532 |
packet_put_cstring(const char *str) |
|
533 |
{
|
|
534 |
buffer_put_cstring(&outgoing_packet, str); |
|
535 |
}
|
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
536 |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
537 |
void
|
538 |
packet_put_raw(const void *buf, u_int len) |
|
539 |
{
|
|
540 |
buffer_append(&outgoing_packet, buf, len); |
|
541 |
}
|
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
542 |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
543 |
void
|
544 |
packet_put_bignum(BIGNUM * value) |
|
545 |
{
|
|
546 |
buffer_put_bignum(&outgoing_packet, value); |
|
547 |
}
|
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
548 |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
549 |
void
|
550 |
packet_put_bignum2(BIGNUM * value) |
|
551 |
{
|
|
552 |
buffer_put_bignum2(&outgoing_packet, value); |
|
553 |
}
|
|
554 |
||
555 |
/*
|
|
556 |
* Finalizes and sends the packet. If the encryption key has been set,
|
|
557 |
* encrypts the packet before sending.
|
|
558 |
*/
|
|
559 |
||
560 |
static void |
|
561 |
packet_send1(void) |
|
562 |
{
|
|
563 |
u_char buf[8], *cp; |
|
564 |
int i, padding, len; |
|
565 |
u_int checksum; |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
566 |
u_int32_t rnd = 0; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
567 |
|
568 |
/*
|
|
569 |
* If using packet compression, compress the payload of the outgoing
|
|
570 |
* packet.
|
|
571 |
*/
|
|
572 |
if (packet_compression) { |
|
573 |
buffer_clear(&compression_buffer); |
|
574 |
/* Skip padding. */
|
|
575 |
buffer_consume(&outgoing_packet, 8); |
|
576 |
/* padding */
|
|
577 |
buffer_append(&compression_buffer, "\0\0\0\0\0\0\0\0", 8); |
|
578 |
buffer_compress(&outgoing_packet, &compression_buffer); |
|
579 |
buffer_clear(&outgoing_packet); |
|
580 |
buffer_append(&outgoing_packet, buffer_ptr(&compression_buffer), |
|
581 |
buffer_len(&compression_buffer)); |
|
582 |
}
|
|
583 |
/* Compute packet length without padding (add checksum, remove padding). */
|
|
584 |
len = buffer_len(&outgoing_packet) + 4 - 8; |
|
585 |
||
586 |
/* Insert padding. Initialized to zero in packet_start1() */
|
|
587 |
padding = 8 - len % 8; |
|
588 |
if (!send_context.plaintext) { |
|
589 |
cp = buffer_ptr(&outgoing_packet); |
|
590 |
for (i = 0; i < padding; i++) { |
|
591 |
if (i % 4 == 0) |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
592 |
rnd = arc4random(); |
593 |
cp[7 - i] = rnd & 0xff; |
|
594 |
rnd >>= 8; |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
595 |
}
|
596 |
}
|
|
597 |
buffer_consume(&outgoing_packet, 8 - padding); |
|
598 |
||
599 |
/* Add check bytes. */
|
|
600 |
checksum = ssh_crc32(buffer_ptr(&outgoing_packet), |
|
601 |
buffer_len(&outgoing_packet)); |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
602 |
put_u32(buf, checksum); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
603 |
buffer_append(&outgoing_packet, buf, 4); |
604 |
||
605 |
#ifdef PACKET_DEBUG
|
|
606 |
fprintf(stderr, "packet_send plain: "); |
|
607 |
buffer_dump(&outgoing_packet); |
|
608 |
#endif
|
|
609 |
||
610 |
/* Append to output. */
|
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
611 |
put_u32(buf, len); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
612 |
buffer_append(&output, buf, 4); |
613 |
cp = buffer_append_space(&output, buffer_len(&outgoing_packet)); |
|
614 |
cipher_crypt(&send_context, cp, buffer_ptr(&outgoing_packet), |
|
615 |
buffer_len(&outgoing_packet)); |
|
616 |
||
617 |
#ifdef PACKET_DEBUG
|
|
618 |
fprintf(stderr, "encrypted: "); |
|
619 |
buffer_dump(&output); |
|
620 |
#endif
|
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
621 |
p_send.packets++; |
622 |
p_send.bytes += len + buffer_len(&outgoing_packet); |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
623 |
buffer_clear(&outgoing_packet); |
624 |
||
625 |
/*
|
|
1.6.1
by Colin Watson
Import upstream version 4.3p2 |
626 |
* Note that the packet is now only buffered in output. It won't be
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
627 |
* actually sent until packet_write_wait or packet_write_poll is
|
628 |
* called.
|
|
629 |
*/
|
|
630 |
}
|
|
631 |
||
632 |
void
|
|
633 |
set_newkeys(int mode) |
|
634 |
{
|
|
635 |
Enc *enc; |
|
636 |
Mac *mac; |
|
637 |
Comp *comp; |
|
638 |
CipherContext *cc; |
|
639 |
u_int64_t *max_blocks; |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
640 |
int crypt_type; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
641 |
|
642 |
debug2("set_newkeys: mode %d", mode); |
|
643 |
||
644 |
if (mode == MODE_OUT) { |
|
645 |
cc = &send_context; |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
646 |
crypt_type = CIPHER_ENCRYPT; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
647 |
p_send.packets = p_send.blocks = 0; |
648 |
max_blocks = &max_blocks_out; |
|
649 |
} else { |
|
650 |
cc = &receive_context; |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
651 |
crypt_type = CIPHER_DECRYPT; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
652 |
p_read.packets = p_read.blocks = 0; |
653 |
max_blocks = &max_blocks_in; |
|
654 |
}
|
|
655 |
if (newkeys[mode] != NULL) { |
|
656 |
debug("set_newkeys: rekeying"); |
|
657 |
cipher_cleanup(cc); |
|
658 |
enc = &newkeys[mode]->enc; |
|
659 |
mac = &newkeys[mode]->mac; |
|
660 |
comp = &newkeys[mode]->comp; |
|
1.13.2
by Colin Watson
Import upstream version 4.7p1 |
661 |
mac_clear(mac); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
662 |
xfree(enc->name); |
663 |
xfree(enc->iv); |
|
664 |
xfree(enc->key); |
|
665 |
xfree(mac->name); |
|
666 |
xfree(mac->key); |
|
667 |
xfree(comp->name); |
|
668 |
xfree(newkeys[mode]); |
|
669 |
}
|
|
670 |
newkeys[mode] = kex_get_newkeys(mode); |
|
671 |
if (newkeys[mode] == NULL) |
|
672 |
fatal("newkeys: no keys for mode %d", mode); |
|
673 |
enc = &newkeys[mode]->enc; |
|
674 |
mac = &newkeys[mode]->mac; |
|
675 |
comp = &newkeys[mode]->comp; |
|
1.13.2
by Colin Watson
Import upstream version 4.7p1 |
676 |
if (mac_init(mac) == 0) |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
677 |
mac->enabled = 1; |
678 |
DBG(debug("cipher_init_context: %d", mode)); |
|
679 |
cipher_init(cc, enc->cipher, enc->key, enc->key_len, |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
680 |
enc->iv, enc->block_size, crypt_type); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
681 |
/* Deleting the keys does not gain extra security */
|
682 |
/* memset(enc->iv, 0, enc->block_size);
|
|
1.13.2
by Colin Watson
Import upstream version 4.7p1 |
683 |
memset(enc->key, 0, enc->key_len);
|
684 |
memset(mac->key, 0, mac->key_len); */
|
|
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
685 |
if ((comp->type == COMP_ZLIB || |
686 |
(comp->type == COMP_DELAYED && after_authentication)) && |
|
687 |
comp->enabled == 0) { |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
688 |
packet_init_compression(); |
689 |
if (mode == MODE_OUT) |
|
690 |
buffer_compress_init_send(6); |
|
691 |
else
|
|
692 |
buffer_compress_init_recv(); |
|
693 |
comp->enabled = 1; |
|
694 |
}
|
|
695 |
/*
|
|
696 |
* The 2^(blocksize*2) limit is too expensive for 3DES,
|
|
697 |
* blowfish, etc, so enforce a 1GB limit for small blocksizes.
|
|
698 |
*/
|
|
699 |
if (enc->block_size >= 16) |
|
700 |
*max_blocks = (u_int64_t)1 << (enc->block_size*2); |
|
701 |
else
|
|
702 |
*max_blocks = ((u_int64_t)1 << 30) / enc->block_size; |
|
703 |
if (rekey_limit) |
|
704 |
*max_blocks = MIN(*max_blocks, rekey_limit / enc->block_size); |
|
705 |
}
|
|
706 |
||
707 |
/*
|
|
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
708 |
* Delayed compression for SSH2 is enabled after authentication:
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
709 |
* This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
|
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
710 |
* and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
|
711 |
*/
|
|
712 |
static void |
|
713 |
packet_enable_delayed_compress(void) |
|
714 |
{
|
|
715 |
Comp *comp = NULL; |
|
716 |
int mode; |
|
717 |
||
718 |
/*
|
|
719 |
* Remember that we are past the authentication step, so rekeying
|
|
720 |
* with COMP_DELAYED will turn on compression immediately.
|
|
721 |
*/
|
|
722 |
after_authentication = 1; |
|
723 |
for (mode = 0; mode < MODE_MAX; mode++) { |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
724 |
/* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
|
725 |
if (newkeys[mode] == NULL) |
|
726 |
continue; |
|
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
727 |
comp = &newkeys[mode]->comp; |
728 |
if (comp && !comp->enabled && comp->type == COMP_DELAYED) { |
|
729 |
packet_init_compression(); |
|
730 |
if (mode == MODE_OUT) |
|
731 |
buffer_compress_init_send(6); |
|
732 |
else
|
|
733 |
buffer_compress_init_recv(); |
|
734 |
comp->enabled = 1; |
|
735 |
}
|
|
736 |
}
|
|
737 |
}
|
|
738 |
||
739 |
/*
|
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
740 |
* Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
|
741 |
*/
|
|
742 |
static void |
|
743 |
packet_send2_wrapped(void) |
|
744 |
{
|
|
745 |
u_char type, *cp, *macbuf = NULL; |
|
746 |
u_char padlen, pad; |
|
747 |
u_int packet_length = 0; |
|
748 |
u_int i, len; |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
749 |
u_int32_t rnd = 0; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
750 |
Enc *enc = NULL; |
751 |
Mac *mac = NULL; |
|
752 |
Comp *comp = NULL; |
|
753 |
int block_size; |
|
754 |
||
755 |
if (newkeys[MODE_OUT] != NULL) { |
|
756 |
enc = &newkeys[MODE_OUT]->enc; |
|
757 |
mac = &newkeys[MODE_OUT]->mac; |
|
758 |
comp = &newkeys[MODE_OUT]->comp; |
|
759 |
}
|
|
760 |
block_size = enc ? enc->block_size : 8; |
|
761 |
||
762 |
cp = buffer_ptr(&outgoing_packet); |
|
763 |
type = cp[5]; |
|
764 |
||
765 |
#ifdef PACKET_DEBUG
|
|
766 |
fprintf(stderr, "plain: "); |
|
767 |
buffer_dump(&outgoing_packet); |
|
768 |
#endif
|
|
769 |
||
770 |
if (comp && comp->enabled) { |
|
771 |
len = buffer_len(&outgoing_packet); |
|
772 |
/* skip header, compress only payload */
|
|
773 |
buffer_consume(&outgoing_packet, 5); |
|
774 |
buffer_clear(&compression_buffer); |
|
775 |
buffer_compress(&outgoing_packet, &compression_buffer); |
|
776 |
buffer_clear(&outgoing_packet); |
|
777 |
buffer_append(&outgoing_packet, "\0\0\0\0\0", 5); |
|
778 |
buffer_append(&outgoing_packet, buffer_ptr(&compression_buffer), |
|
779 |
buffer_len(&compression_buffer)); |
|
780 |
DBG(debug("compression: raw %d compressed %d", len, |
|
781 |
buffer_len(&outgoing_packet))); |
|
782 |
}
|
|
783 |
||
784 |
/* sizeof (packet_len + pad_len + payload) */
|
|
785 |
len = buffer_len(&outgoing_packet); |
|
786 |
||
787 |
/*
|
|
788 |
* calc size of padding, alloc space, get random data,
|
|
789 |
* minimum padding is 4 bytes
|
|
790 |
*/
|
|
791 |
padlen = block_size - (len % block_size); |
|
792 |
if (padlen < 4) |
|
793 |
padlen += block_size; |
|
794 |
if (extra_pad) { |
|
795 |
/* will wrap if extra_pad+padlen > 255 */
|
|
796 |
extra_pad = roundup(extra_pad, block_size); |
|
797 |
pad = extra_pad - ((len + padlen) % extra_pad); |
|
798 |
debug3("packet_send2: adding %d (len %d padlen %d extra_pad %d)", |
|
799 |
pad, len, padlen, extra_pad); |
|
800 |
padlen += pad; |
|
801 |
extra_pad = 0; |
|
802 |
}
|
|
803 |
cp = buffer_append_space(&outgoing_packet, padlen); |
|
804 |
if (enc && !send_context.plaintext) { |
|
805 |
/* random padding */
|
|
806 |
for (i = 0; i < padlen; i++) { |
|
807 |
if (i % 4 == 0) |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
808 |
rnd = arc4random(); |
809 |
cp[i] = rnd & 0xff; |
|
810 |
rnd >>= 8; |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
811 |
}
|
812 |
} else { |
|
813 |
/* clear padding */
|
|
814 |
memset(cp, 0, padlen); |
|
815 |
}
|
|
816 |
/* packet_length includes payload, padding and padding length field */
|
|
817 |
packet_length = buffer_len(&outgoing_packet) - 4; |
|
818 |
cp = buffer_ptr(&outgoing_packet); |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
819 |
put_u32(cp, packet_length); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
820 |
cp[4] = padlen; |
821 |
DBG(debug("send: len %d (includes padlen %d)", packet_length+4, padlen)); |
|
822 |
||
823 |
/* compute MAC over seqnr and packet(length fields, payload, padding) */
|
|
824 |
if (mac && mac->enabled) { |
|
825 |
macbuf = mac_compute(mac, p_send.seqnr, |
|
826 |
buffer_ptr(&outgoing_packet), |
|
827 |
buffer_len(&outgoing_packet)); |
|
828 |
DBG(debug("done calc MAC out #%d", p_send.seqnr)); |
|
829 |
}
|
|
830 |
/* encrypt packet and append to output buffer. */
|
|
831 |
cp = buffer_append_space(&output, buffer_len(&outgoing_packet)); |
|
832 |
cipher_crypt(&send_context, cp, buffer_ptr(&outgoing_packet), |
|
833 |
buffer_len(&outgoing_packet)); |
|
834 |
/* append unencrypted MAC */
|
|
835 |
if (mac && mac->enabled) |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
836 |
buffer_append(&output, macbuf, mac->mac_len); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
837 |
#ifdef PACKET_DEBUG
|
838 |
fprintf(stderr, "encrypted: "); |
|
839 |
buffer_dump(&output); |
|
840 |
#endif
|
|
841 |
/* increment sequence number for outgoing packets */
|
|
842 |
if (++p_send.seqnr == 0) |
|
843 |
logit("outgoing seqnr wraps around"); |
|
844 |
if (++p_send.packets == 0) |
|
845 |
if (!(datafellows & SSH_BUG_NOREKEY)) |
|
846 |
fatal("XXX too many packets with same key"); |
|
847 |
p_send.blocks += (packet_length + 4) / block_size; |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
848 |
p_send.bytes += packet_length + 4; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
849 |
buffer_clear(&outgoing_packet); |
850 |
||
851 |
if (type == SSH2_MSG_NEWKEYS) |
|
852 |
set_newkeys(MODE_OUT); |
|
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
853 |
else if (type == SSH2_MSG_USERAUTH_SUCCESS && server_side) |
854 |
packet_enable_delayed_compress(); |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
855 |
}
|
856 |
||
857 |
static void |
|
858 |
packet_send2(void) |
|
859 |
{
|
|
860 |
static int rekeying = 0; |
|
861 |
struct packet *p; |
|
862 |
u_char type, *cp; |
|
863 |
||
864 |
cp = buffer_ptr(&outgoing_packet); |
|
865 |
type = cp[5]; |
|
866 |
||
867 |
/* during rekeying we can only send key exchange messages */
|
|
868 |
if (rekeying) { |
|
869 |
if (!((type >= SSH2_MSG_TRANSPORT_MIN) && |
|
870 |
(type <= SSH2_MSG_TRANSPORT_MAX))) { |
|
871 |
debug("enqueue packet: %u", type); |
|
872 |
p = xmalloc(sizeof(*p)); |
|
873 |
p->type = type; |
|
874 |
memcpy(&p->payload, &outgoing_packet, sizeof(Buffer)); |
|
875 |
buffer_init(&outgoing_packet); |
|
876 |
TAILQ_INSERT_TAIL(&outgoing, p, next); |
|
877 |
return; |
|
878 |
}
|
|
879 |
}
|
|
880 |
||
881 |
/* rekeying starts with sending KEXINIT */
|
|
882 |
if (type == SSH2_MSG_KEXINIT) |
|
883 |
rekeying = 1; |
|
884 |
||
885 |
packet_send2_wrapped(); |
|
886 |
||
887 |
/* after a NEWKEYS message we can send the complete queue */
|
|
888 |
if (type == SSH2_MSG_NEWKEYS) { |
|
889 |
rekeying = 0; |
|
890 |
while ((p = TAILQ_FIRST(&outgoing))) { |
|
891 |
type = p->type; |
|
892 |
debug("dequeue packet: %u", type); |
|
893 |
buffer_free(&outgoing_packet); |
|
894 |
memcpy(&outgoing_packet, &p->payload, |
|
895 |
sizeof(Buffer)); |
|
896 |
TAILQ_REMOVE(&outgoing, p, next); |
|
897 |
xfree(p); |
|
898 |
packet_send2_wrapped(); |
|
899 |
}
|
|
900 |
}
|
|
901 |
}
|
|
902 |
||
903 |
void
|
|
904 |
packet_send(void) |
|
905 |
{
|
|
906 |
if (compat20) |
|
907 |
packet_send2(); |
|
908 |
else
|
|
909 |
packet_send1(); |
|
910 |
DBG(debug("packet_send done")); |
|
911 |
}
|
|
912 |
||
913 |
/*
|
|
914 |
* Waits until a packet has been received, and returns its type. Note that
|
|
915 |
* no other data is processed until this returns, so this function should not
|
|
916 |
* be used during the interactive session.
|
|
917 |
*/
|
|
918 |
||
919 |
int
|
|
920 |
packet_read_seqnr(u_int32_t *seqnr_p) |
|
921 |
{
|
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
922 |
int type, len, ret, ms_remain; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
923 |
fd_set *setp; |
924 |
char buf[8192]; |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
925 |
struct timeval timeout, start, *timeoutp = NULL; |
926 |
||
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
927 |
DBG(debug("packet_read()")); |
928 |
||
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
929 |
setp = (fd_set *)xcalloc(howmany(connection_in+1, NFDBITS), |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
930 |
sizeof(fd_mask)); |
931 |
||
932 |
/* Since we are blocking, ensure that all written packets have been sent. */
|
|
933 |
packet_write_wait(); |
|
934 |
||
935 |
/* Stay in the loop until we have received a complete packet. */
|
|
936 |
for (;;) { |
|
937 |
/* Try to read a packet from the buffer. */
|
|
938 |
type = packet_read_poll_seqnr(seqnr_p); |
|
939 |
if (!compat20 && ( |
|
940 |
type == SSH_SMSG_SUCCESS |
|
941 |
|| type == SSH_SMSG_FAILURE |
|
942 |
|| type == SSH_CMSG_EOF |
|
943 |
|| type == SSH_CMSG_EXIT_CONFIRMATION)) |
|
944 |
packet_check_eom(); |
|
945 |
/* If we got a packet, return it. */
|
|
946 |
if (type != SSH_MSG_NONE) { |
|
947 |
xfree(setp); |
|
948 |
return type; |
|
949 |
}
|
|
950 |
/*
|
|
951 |
* Otherwise, wait for some data to arrive, add it to the
|
|
952 |
* buffer, and try again.
|
|
953 |
*/
|
|
954 |
memset(setp, 0, howmany(connection_in + 1, NFDBITS) * |
|
955 |
sizeof(fd_mask)); |
|
956 |
FD_SET(connection_in, setp); |
|
957 |
||
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
958 |
if (packet_timeout_ms > 0) { |
959 |
ms_remain = packet_timeout_ms; |
|
960 |
timeoutp = &timeout; |
|
961 |
}
|
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
962 |
/* Wait for some data to arrive. */
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
963 |
for (;;) { |
964 |
if (packet_timeout_ms != -1) { |
|
965 |
ms_to_timeval(&timeout, ms_remain); |
|
966 |
gettimeofday(&start, NULL); |
|
967 |
}
|
|
968 |
if ((ret = select(connection_in + 1, setp, NULL, |
|
969 |
NULL, timeoutp)) >= 0) |
|
970 |
break; |
|
971 |
if (errno != EAGAIN && errno != EINTR && |
|
972 |
errno != EWOULDBLOCK) |
|
973 |
break; |
|
974 |
if (packet_timeout_ms == -1) |
|
975 |
continue; |
|
976 |
ms_subtract_diff(&start, &ms_remain); |
|
977 |
if (ms_remain <= 0) { |
|
978 |
ret = 0; |
|
979 |
break; |
|
980 |
}
|
|
981 |
}
|
|
982 |
if (ret == 0) { |
|
983 |
logit("Connection to %.200s timed out while " |
|
984 |
"waiting to read", get_remote_ipaddr()); |
|
985 |
cleanup_exit(255); |
|
986 |
}
|
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
987 |
/* Read data from the socket. */
|
988 |
len = read(connection_in, buf, sizeof(buf)); |
|
989 |
if (len == 0) { |
|
990 |
logit("Connection closed by %.200s", get_remote_ipaddr()); |
|
991 |
cleanup_exit(255); |
|
992 |
}
|
|
993 |
if (len < 0) |
|
994 |
fatal("Read from socket failed: %.100s", strerror(errno)); |
|
995 |
/* Append it to the buffer. */
|
|
996 |
packet_process_incoming(buf, len); |
|
997 |
}
|
|
998 |
/* NOTREACHED */
|
|
999 |
}
|
|
1000 |
||
1001 |
int
|
|
1002 |
packet_read(void) |
|
1003 |
{
|
|
1004 |
return packet_read_seqnr(NULL); |
|
1005 |
}
|
|
1006 |
||
1007 |
/*
|
|
1008 |
* Waits until a packet has been received, verifies that its type matches
|
|
1009 |
* that given, and gives a fatal error and exits if there is a mismatch.
|
|
1010 |
*/
|
|
1011 |
||
1012 |
void
|
|
1013 |
packet_read_expect(int expected_type) |
|
1014 |
{
|
|
1015 |
int type; |
|
1016 |
||
1017 |
type = packet_read(); |
|
1018 |
if (type != expected_type) |
|
1019 |
packet_disconnect("Protocol error: expected packet type %d, got %d", |
|
1020 |
expected_type, type); |
|
1021 |
}
|
|
1022 |
||
1023 |
/* Checks if a full packet is available in the data received so far via
|
|
1024 |
* packet_process_incoming. If so, reads the packet; otherwise returns
|
|
1025 |
* SSH_MSG_NONE. This does not wait for data from the connection.
|
|
1026 |
*
|
|
1027 |
* SSH_MSG_DISCONNECT is handled specially here. Also,
|
|
1028 |
* SSH_MSG_IGNORE messages are skipped by this function and are never returned
|
|
1029 |
* to higher levels.
|
|
1030 |
*/
|
|
1031 |
||
1032 |
static int |
|
1033 |
packet_read_poll1(void) |
|
1034 |
{
|
|
1035 |
u_int len, padded_len; |
|
1036 |
u_char *cp, type; |
|
1037 |
u_int checksum, stored_checksum; |
|
1038 |
||
1039 |
/* Check if input size is less than minimum packet size. */
|
|
1040 |
if (buffer_len(&input) < 4 + 8) |
|
1041 |
return SSH_MSG_NONE; |
|
1042 |
/* Get length of incoming packet. */
|
|
1043 |
cp = buffer_ptr(&input); |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
1044 |
len = get_u32(cp); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1045 |
if (len < 1 + 2 + 2 || len > 256 * 1024) |
1046 |
packet_disconnect("Bad packet length %u.", len); |
|
1047 |
padded_len = (len + 8) & ~7; |
|
1048 |
||
1049 |
/* Check if the packet has been entirely received. */
|
|
1050 |
if (buffer_len(&input) < 4 + padded_len) |
|
1051 |
return SSH_MSG_NONE; |
|
1052 |
||
1053 |
/* The entire packet is in buffer. */
|
|
1054 |
||
1055 |
/* Consume packet length. */
|
|
1056 |
buffer_consume(&input, 4); |
|
1057 |
||
1058 |
/*
|
|
1059 |
* Cryptographic attack detector for ssh
|
|
1060 |
* (C)1998 CORE-SDI, Buenos Aires Argentina
|
|
1061 |
* Ariel Futoransky(futo@core-sdi.com)
|
|
1062 |
*/
|
|
15
by Colin Watson
Resynchronise with Debian. |
1063 |
if (!receive_context.plaintext) { |
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
1064 |
switch (detect_attack(buffer_ptr(&input), padded_len)) { |
15
by Colin Watson
Resynchronise with Debian. |
1065 |
case DEATTACK_DETECTED: |
1066 |
packet_disconnect("crc32 compensation attack: " |
|
1067 |
"network attack detected"); |
|
1068 |
case DEATTACK_DOS_DETECTED: |
|
1069 |
packet_disconnect("deattack denial of " |
|
1070 |
"service detected"); |
|
1071 |
}
|
|
1072 |
}
|
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1073 |
|
1074 |
/* Decrypt data to incoming_packet. */
|
|
1075 |
buffer_clear(&incoming_packet); |
|
1076 |
cp = buffer_append_space(&incoming_packet, padded_len); |
|
1077 |
cipher_crypt(&receive_context, cp, buffer_ptr(&input), padded_len); |
|
1078 |
||
1079 |
buffer_consume(&input, padded_len); |
|
1080 |
||
1081 |
#ifdef PACKET_DEBUG
|
|
1082 |
fprintf(stderr, "read_poll plain: "); |
|
1083 |
buffer_dump(&incoming_packet); |
|
1084 |
#endif
|
|
1085 |
||
1086 |
/* Compute packet checksum. */
|
|
1087 |
checksum = ssh_crc32(buffer_ptr(&incoming_packet), |
|
1088 |
buffer_len(&incoming_packet) - 4); |
|
1089 |
||
1090 |
/* Skip padding. */
|
|
1091 |
buffer_consume(&incoming_packet, 8 - len % 8); |
|
1092 |
||
1093 |
/* Test check bytes. */
|
|
1094 |
if (len != buffer_len(&incoming_packet)) |
|
1095 |
packet_disconnect("packet_read_poll1: len %d != buffer_len %d.", |
|
1096 |
len, buffer_len(&incoming_packet)); |
|
1097 |
||
1098 |
cp = (u_char *)buffer_ptr(&incoming_packet) + len - 4; |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
1099 |
stored_checksum = get_u32(cp); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1100 |
if (checksum != stored_checksum) |
1101 |
packet_disconnect("Corrupted check bytes on input."); |
|
1102 |
buffer_consume_end(&incoming_packet, 4); |
|
1103 |
||
1104 |
if (packet_compression) { |
|
1105 |
buffer_clear(&compression_buffer); |
|
1106 |
buffer_uncompress(&incoming_packet, &compression_buffer); |
|
1107 |
buffer_clear(&incoming_packet); |
|
1108 |
buffer_append(&incoming_packet, buffer_ptr(&compression_buffer), |
|
1109 |
buffer_len(&compression_buffer)); |
|
1110 |
}
|
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1111 |
p_read.packets++; |
1112 |
p_read.bytes += padded_len + 4; |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1113 |
type = buffer_get_char(&incoming_packet); |
1.1.2
by Colin Watson
Import upstream version 4.1p1 |
1114 |
if (type < SSH_MSG_MIN || type > SSH_MSG_MAX) |
1115 |
packet_disconnect("Invalid ssh1 packet type: %d", type); |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1116 |
return type; |
1117 |
}
|
|
1118 |
||
1119 |
static int |
|
1120 |
packet_read_poll2(u_int32_t *seqnr_p) |
|
1121 |
{
|
|
1122 |
static u_int packet_length = 0; |
|
1123 |
u_int padlen, need; |
|
1124 |
u_char *macbuf, *cp, type; |
|
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
1125 |
u_int maclen, block_size; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1126 |
Enc *enc = NULL; |
1127 |
Mac *mac = NULL; |
|
1128 |
Comp *comp = NULL; |
|
1129 |
||
1130 |
if (newkeys[MODE_IN] != NULL) { |
|
1131 |
enc = &newkeys[MODE_IN]->enc; |
|
1132 |
mac = &newkeys[MODE_IN]->mac; |
|
1133 |
comp = &newkeys[MODE_IN]->comp; |
|
1134 |
}
|
|
1135 |
maclen = mac && mac->enabled ? mac->mac_len : 0; |
|
1136 |
block_size = enc ? enc->block_size : 8; |
|
1137 |
||
1138 |
if (packet_length == 0) { |
|
1139 |
/*
|
|
1140 |
* check if input size is less than the cipher block size,
|
|
1141 |
* decrypt first block and extract length of incoming packet
|
|
1142 |
*/
|
|
1143 |
if (buffer_len(&input) < block_size) |
|
1144 |
return SSH_MSG_NONE; |
|
1145 |
buffer_clear(&incoming_packet); |
|
1146 |
cp = buffer_append_space(&incoming_packet, block_size); |
|
1147 |
cipher_crypt(&receive_context, cp, buffer_ptr(&input), |
|
1148 |
block_size); |
|
1149 |
cp = buffer_ptr(&incoming_packet); |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
1150 |
packet_length = get_u32(cp); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1151 |
if (packet_length < 1 + 4 || packet_length > 256 * 1024) { |
1152 |
#ifdef PACKET_DEBUG
|
|
1153 |
buffer_dump(&incoming_packet); |
|
1154 |
#endif
|
|
1155 |
packet_disconnect("Bad packet length %u.", packet_length); |
|
1156 |
}
|
|
1157 |
DBG(debug("input: packet len %u", packet_length+4)); |
|
1158 |
buffer_consume(&input, block_size); |
|
1159 |
}
|
|
1160 |
/* we have a partial packet of block_size bytes */
|
|
1161 |
need = 4 + packet_length - block_size; |
|
1162 |
DBG(debug("partial packet %d, need %d, maclen %d", block_size, |
|
1163 |
need, maclen)); |
|
1164 |
if (need % block_size != 0) |
|
1165 |
fatal("padding error: need %d block %d mod %d", |
|
1166 |
need, block_size, need % block_size); |
|
1167 |
/*
|
|
1168 |
* check if the entire packet has been received and
|
|
1169 |
* decrypt into incoming_packet
|
|
1170 |
*/
|
|
1171 |
if (buffer_len(&input) < need + maclen) |
|
1172 |
return SSH_MSG_NONE; |
|
1173 |
#ifdef PACKET_DEBUG
|
|
1174 |
fprintf(stderr, "read_poll enc/full: "); |
|
1175 |
buffer_dump(&input); |
|
1176 |
#endif
|
|
1177 |
cp = buffer_append_space(&incoming_packet, need); |
|
1178 |
cipher_crypt(&receive_context, cp, buffer_ptr(&input), need); |
|
1179 |
buffer_consume(&input, need); |
|
1180 |
/*
|
|
1181 |
* compute MAC over seqnr and packet,
|
|
1182 |
* increment sequence number for incoming packet
|
|
1183 |
*/
|
|
1184 |
if (mac && mac->enabled) { |
|
1185 |
macbuf = mac_compute(mac, p_read.seqnr, |
|
1186 |
buffer_ptr(&incoming_packet), |
|
1187 |
buffer_len(&incoming_packet)); |
|
1188 |
if (memcmp(macbuf, buffer_ptr(&input), mac->mac_len) != 0) |
|
1189 |
packet_disconnect("Corrupted MAC on input."); |
|
1190 |
DBG(debug("MAC #%d ok", p_read.seqnr)); |
|
1191 |
buffer_consume(&input, mac->mac_len); |
|
1192 |
}
|
|
1193 |
if (seqnr_p != NULL) |
|
1194 |
*seqnr_p = p_read.seqnr; |
|
1195 |
if (++p_read.seqnr == 0) |
|
1196 |
logit("incoming seqnr wraps around"); |
|
1197 |
if (++p_read.packets == 0) |
|
1198 |
if (!(datafellows & SSH_BUG_NOREKEY)) |
|
1199 |
fatal("XXX too many packets with same key"); |
|
1200 |
p_read.blocks += (packet_length + 4) / block_size; |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1201 |
p_read.bytes += packet_length + 4; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1202 |
|
1203 |
/* get padlen */
|
|
1204 |
cp = buffer_ptr(&incoming_packet); |
|
1205 |
padlen = cp[4]; |
|
1206 |
DBG(debug("input: padlen %d", padlen)); |
|
1207 |
if (padlen < 4) |
|
1208 |
packet_disconnect("Corrupted padlen %d on input.", padlen); |
|
1209 |
||
1210 |
/* skip packet size + padlen, discard padding */
|
|
1211 |
buffer_consume(&incoming_packet, 4 + 1); |
|
1212 |
buffer_consume_end(&incoming_packet, padlen); |
|
1213 |
||
1214 |
DBG(debug("input: len before de-compress %d", buffer_len(&incoming_packet))); |
|
1215 |
if (comp && comp->enabled) { |
|
1216 |
buffer_clear(&compression_buffer); |
|
1217 |
buffer_uncompress(&incoming_packet, &compression_buffer); |
|
1218 |
buffer_clear(&incoming_packet); |
|
1219 |
buffer_append(&incoming_packet, buffer_ptr(&compression_buffer), |
|
1220 |
buffer_len(&compression_buffer)); |
|
1221 |
DBG(debug("input: len after de-compress %d", |
|
1222 |
buffer_len(&incoming_packet))); |
|
1223 |
}
|
|
1224 |
/*
|
|
1225 |
* get packet type, implies consume.
|
|
1226 |
* return length of payload (without type field)
|
|
1227 |
*/
|
|
1228 |
type = buffer_get_char(&incoming_packet); |
|
1.1.2
by Colin Watson
Import upstream version 4.1p1 |
1229 |
if (type < SSH2_MSG_MIN || type >= SSH2_MSG_LOCAL_MIN) |
1230 |
packet_disconnect("Invalid ssh2 packet type: %d", type); |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1231 |
if (type == SSH2_MSG_NEWKEYS) |
1232 |
set_newkeys(MODE_IN); |
|
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
1233 |
else if (type == SSH2_MSG_USERAUTH_SUCCESS && !server_side) |
1234 |
packet_enable_delayed_compress(); |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1235 |
#ifdef PACKET_DEBUG
|
1236 |
fprintf(stderr, "read/plain[%d]:\r\n", type); |
|
1237 |
buffer_dump(&incoming_packet); |
|
1238 |
#endif
|
|
1239 |
/* reset for next packet */
|
|
1240 |
packet_length = 0; |
|
1241 |
return type; |
|
1242 |
}
|
|
1243 |
||
1244 |
int
|
|
1245 |
packet_read_poll_seqnr(u_int32_t *seqnr_p) |
|
1246 |
{
|
|
1247 |
u_int reason, seqnr; |
|
1248 |
u_char type; |
|
1249 |
char *msg; |
|
1250 |
||
1251 |
for (;;) { |
|
1252 |
if (compat20) { |
|
1253 |
type = packet_read_poll2(seqnr_p); |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1254 |
if (type) { |
1255 |
keep_alive_timeouts = 0; |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1256 |
DBG(debug("received packet type %d", type)); |
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1257 |
}
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1258 |
switch (type) { |
1259 |
case SSH2_MSG_IGNORE: |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1260 |
debug3("Received SSH2_MSG_IGNORE"); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1261 |
break; |
1262 |
case SSH2_MSG_DEBUG: |
|
1263 |
packet_get_char(); |
|
1264 |
msg = packet_get_string(NULL); |
|
1265 |
debug("Remote: %.900s", msg); |
|
1266 |
xfree(msg); |
|
1267 |
msg = packet_get_string(NULL); |
|
1268 |
xfree(msg); |
|
1269 |
break; |
|
1270 |
case SSH2_MSG_DISCONNECT: |
|
1271 |
reason = packet_get_int(); |
|
1272 |
msg = packet_get_string(NULL); |
|
1273 |
logit("Received disconnect from %s: %u: %.400s", |
|
1274 |
get_remote_ipaddr(), reason, msg); |
|
1275 |
xfree(msg); |
|
1276 |
cleanup_exit(255); |
|
1277 |
break; |
|
1278 |
case SSH2_MSG_UNIMPLEMENTED: |
|
1279 |
seqnr = packet_get_int(); |
|
1280 |
debug("Received SSH2_MSG_UNIMPLEMENTED for %u", |
|
1281 |
seqnr); |
|
1282 |
break; |
|
1283 |
default: |
|
1284 |
return type; |
|
1285 |
}
|
|
1286 |
} else { |
|
1287 |
type = packet_read_poll1(); |
|
1288 |
switch (type) { |
|
1289 |
case SSH_MSG_IGNORE: |
|
1290 |
break; |
|
1291 |
case SSH_MSG_DEBUG: |
|
1292 |
msg = packet_get_string(NULL); |
|
1293 |
debug("Remote: %.900s", msg); |
|
1294 |
xfree(msg); |
|
1295 |
break; |
|
1296 |
case SSH_MSG_DISCONNECT: |
|
1297 |
msg = packet_get_string(NULL); |
|
1298 |
logit("Received disconnect from %s: %.400s", |
|
1299 |
get_remote_ipaddr(), msg); |
|
1300 |
cleanup_exit(255); |
|
1301 |
break; |
|
1302 |
default: |
|
1303 |
if (type) |
|
1304 |
DBG(debug("received packet type %d", type)); |
|
1305 |
return type; |
|
1306 |
}
|
|
1307 |
}
|
|
1308 |
}
|
|
1309 |
}
|
|
1310 |
||
1311 |
int
|
|
1312 |
packet_read_poll(void) |
|
1313 |
{
|
|
1314 |
return packet_read_poll_seqnr(NULL); |
|
1315 |
}
|
|
1316 |
||
1317 |
/*
|
|
1318 |
* Buffers the given amount of input characters. This is intended to be used
|
|
1319 |
* together with packet_read_poll.
|
|
1320 |
*/
|
|
1321 |
||
1322 |
void
|
|
1323 |
packet_process_incoming(const char *buf, u_int len) |
|
1324 |
{
|
|
1325 |
buffer_append(&input, buf, len); |
|
1326 |
}
|
|
1327 |
||
1328 |
/* Returns a character from the packet. */
|
|
1329 |
||
1330 |
u_int
|
|
1331 |
packet_get_char(void) |
|
1332 |
{
|
|
1333 |
char ch; |
|
1334 |
||
1335 |
buffer_get(&incoming_packet, &ch, 1); |
|
1336 |
return (u_char) ch; |
|
1337 |
}
|
|
1338 |
||
1339 |
/* Returns an integer from the packet data. */
|
|
1340 |
||
1341 |
u_int
|
|
1342 |
packet_get_int(void) |
|
1343 |
{
|
|
1344 |
return buffer_get_int(&incoming_packet); |
|
1345 |
}
|
|
1346 |
||
1347 |
/*
|
|
1348 |
* Returns an arbitrary precision integer from the packet data. The integer
|
|
1349 |
* must have been initialized before this call.
|
|
1350 |
*/
|
|
1351 |
||
1352 |
void
|
|
1353 |
packet_get_bignum(BIGNUM * value) |
|
1354 |
{
|
|
1355 |
buffer_get_bignum(&incoming_packet, value); |
|
1356 |
}
|
|
1357 |
||
1358 |
void
|
|
1359 |
packet_get_bignum2(BIGNUM * value) |
|
1360 |
{
|
|
1361 |
buffer_get_bignum2(&incoming_packet, value); |
|
1362 |
}
|
|
1363 |
||
1364 |
void * |
|
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
1365 |
packet_get_raw(u_int *length_ptr) |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1366 |
{
|
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
1367 |
u_int bytes = buffer_len(&incoming_packet); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1368 |
|
1369 |
if (length_ptr != NULL) |
|
1370 |
*length_ptr = bytes; |
|
1371 |
return buffer_ptr(&incoming_packet); |
|
1372 |
}
|
|
1373 |
||
1374 |
int
|
|
1375 |
packet_remaining(void) |
|
1376 |
{
|
|
1377 |
return buffer_len(&incoming_packet); |
|
1378 |
}
|
|
1379 |
||
1380 |
/*
|
|
1381 |
* Returns a string from the packet data. The string is allocated using
|
|
1382 |
* xmalloc; it is the responsibility of the calling program to free it when
|
|
1383 |
* no longer needed. The length_ptr argument may be NULL, or point to an
|
|
1384 |
* integer into which the length of the string is stored.
|
|
1385 |
*/
|
|
1386 |
||
1387 |
void * |
|
1388 |
packet_get_string(u_int *length_ptr) |
|
1389 |
{
|
|
1390 |
return buffer_get_string(&incoming_packet, length_ptr); |
|
1391 |
}
|
|
1392 |
||
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1393 |
void * |
1394 |
packet_get_string_ptr(u_int *length_ptr) |
|
1395 |
{
|
|
1396 |
return buffer_get_string_ptr(&incoming_packet, length_ptr); |
|
1397 |
}
|
|
1398 |
||
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1399 |
/*
|
1400 |
* Sends a diagnostic message from the server to the client. This message
|
|
1401 |
* can be sent at any time (but not while constructing another message). The
|
|
1402 |
* message is printed immediately, but only if the client is being executed
|
|
1403 |
* in verbose mode. These messages are primarily intended to ease debugging
|
|
1404 |
* authentication problems. The length of the formatted message must not
|
|
1405 |
* exceed 1024 bytes. This will automatically call packet_write_wait.
|
|
1406 |
*/
|
|
1407 |
||
1408 |
void
|
|
1409 |
packet_send_debug(const char *fmt,...) |
|
1410 |
{
|
|
1411 |
char buf[1024]; |
|
1412 |
va_list args; |
|
1413 |
||
1414 |
if (compat20 && (datafellows & SSH_BUG_DEBUG)) |
|
1415 |
return; |
|
1416 |
||
1417 |
va_start(args, fmt); |
|
1418 |
vsnprintf(buf, sizeof(buf), fmt, args); |
|
1419 |
va_end(args); |
|
1420 |
||
1421 |
if (compat20) { |
|
1422 |
packet_start(SSH2_MSG_DEBUG); |
|
1423 |
packet_put_char(0); /* bool: always display */ |
|
1424 |
packet_put_cstring(buf); |
|
1425 |
packet_put_cstring(""); |
|
1426 |
} else { |
|
1427 |
packet_start(SSH_MSG_DEBUG); |
|
1428 |
packet_put_cstring(buf); |
|
1429 |
}
|
|
1430 |
packet_send(); |
|
1431 |
packet_write_wait(); |
|
1432 |
}
|
|
1433 |
||
1434 |
/*
|
|
1435 |
* Logs the error plus constructs and sends a disconnect packet, closes the
|
|
1436 |
* connection, and exits. This function never returns. The error message
|
|
1437 |
* should not contain a newline. The length of the formatted message must
|
|
1438 |
* not exceed 1024 bytes.
|
|
1439 |
*/
|
|
1440 |
||
1441 |
void
|
|
1442 |
packet_disconnect(const char *fmt,...) |
|
1443 |
{
|
|
1444 |
char buf[1024]; |
|
1445 |
va_list args; |
|
1446 |
static int disconnecting = 0; |
|
1447 |
||
1448 |
if (disconnecting) /* Guard against recursive invocations. */ |
|
1449 |
fatal("packet_disconnect called recursively."); |
|
1450 |
disconnecting = 1; |
|
1451 |
||
1452 |
/*
|
|
1453 |
* Format the message. Note that the caller must make sure the
|
|
1454 |
* message is of limited size.
|
|
1455 |
*/
|
|
1456 |
va_start(args, fmt); |
|
1457 |
vsnprintf(buf, sizeof(buf), fmt, args); |
|
1458 |
va_end(args); |
|
1459 |
||
1460 |
/* Display the error locally */
|
|
1461 |
logit("Disconnecting: %.100s", buf); |
|
1462 |
||
1463 |
/* Send the disconnect message to the other side, and wait for it to get sent. */
|
|
1464 |
if (compat20) { |
|
1465 |
packet_start(SSH2_MSG_DISCONNECT); |
|
1466 |
packet_put_int(SSH2_DISCONNECT_PROTOCOL_ERROR); |
|
1467 |
packet_put_cstring(buf); |
|
1468 |
packet_put_cstring(""); |
|
1469 |
} else { |
|
1470 |
packet_start(SSH_MSG_DISCONNECT); |
|
1471 |
packet_put_cstring(buf); |
|
1472 |
}
|
|
1473 |
packet_send(); |
|
1474 |
packet_write_wait(); |
|
1475 |
||
1476 |
/* Stop listening for connections. */
|
|
1477 |
channel_close_all(); |
|
1478 |
||
1479 |
/* Close the connection. */
|
|
1480 |
packet_close(); |
|
1481 |
cleanup_exit(255); |
|
1482 |
}
|
|
1483 |
||
1484 |
/* Checks if there is any buffered output, and tries to write some of the output. */
|
|
1485 |
||
1486 |
void
|
|
1487 |
packet_write_poll(void) |
|
1488 |
{
|
|
1489 |
int len = buffer_len(&output); |
|
1490 |
||
1491 |
if (len > 0) { |
|
1492 |
len = write(connection_out, buffer_ptr(&output), len); |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1493 |
if (len == -1) { |
1494 |
if (errno == EINTR || errno == EAGAIN || |
|
1495 |
errno == EWOULDBLOCK) |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1496 |
return; |
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1497 |
fatal("Write failed: %.100s", strerror(errno)); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1498 |
}
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1499 |
if (len == 0) |
1500 |
fatal("Write connection closed"); |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1501 |
buffer_consume(&output, len); |
1502 |
}
|
|
1503 |
}
|
|
1504 |
||
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1505 |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1506 |
/*
|
1507 |
* Calls packet_write_poll repeatedly until all pending output data has been
|
|
1508 |
* written.
|
|
1509 |
*/
|
|
1510 |
||
1511 |
void
|
|
1512 |
packet_write_wait(void) |
|
1513 |
{
|
|
1514 |
fd_set *setp; |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1515 |
int ret, ms_remain; |
1516 |
struct timeval start, timeout, *timeoutp = NULL; |
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1517 |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
1518 |
setp = (fd_set *)xcalloc(howmany(connection_out + 1, NFDBITS), |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1519 |
sizeof(fd_mask)); |
1520 |
packet_write_poll(); |
|
1521 |
while (packet_have_data_to_write()) { |
|
1522 |
memset(setp, 0, howmany(connection_out + 1, NFDBITS) * |
|
1523 |
sizeof(fd_mask)); |
|
1524 |
FD_SET(connection_out, setp); |
|
1.13.3
by Colin Watson
Import upstream version 5.1p1 |
1525 |
|
1526 |
if (packet_timeout_ms > 0) { |
|
1527 |
ms_remain = packet_timeout_ms; |
|
1528 |
timeoutp = &timeout; |
|
1529 |
}
|
|
1530 |
for (;;) { |
|
1531 |
if (packet_timeout_ms != -1) { |
|
1532 |
ms_to_timeval(&timeout, ms_remain); |
|
1533 |
gettimeofday(&start, NULL); |
|
1534 |
}
|
|
1535 |
if ((ret = select(connection_out + 1, NULL, setp, |
|
1536 |
NULL, timeoutp)) >= 0) |
|
1537 |
break; |
|
1538 |
if (errno != EAGAIN && errno != EINTR && |
|
1539 |
errno != EWOULDBLOCK) |
|
1540 |
break; |
|
1541 |
if (packet_timeout_ms == -1) |
|
1542 |
continue; |
|
1543 |
ms_subtract_diff(&start, &ms_remain); |
|
1544 |
if (ms_remain <= 0) { |
|
1545 |
ret = 0; |
|
1546 |
break; |
|
1547 |
}
|
|
1548 |
}
|
|
1549 |
if (ret == 0) { |
|
1550 |
logit("Connection to %.200s timed out while " |
|
1551 |
"waiting to write", get_remote_ipaddr()); |
|
1552 |
cleanup_exit(255); |
|
1553 |
}
|
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1554 |
packet_write_poll(); |
1555 |
}
|
|
1556 |
xfree(setp); |
|
1557 |
}
|
|
1558 |
||
1559 |
/* Returns true if there is buffered data to write to the connection. */
|
|
1560 |
||
1561 |
int
|
|
1562 |
packet_have_data_to_write(void) |
|
1563 |
{
|
|
1564 |
return buffer_len(&output) != 0; |
|
1565 |
}
|
|
1566 |
||
1567 |
/* Returns true if there is not too much data to write to the connection. */
|
|
1568 |
||
1569 |
int
|
|
1570 |
packet_not_very_much_data_to_write(void) |
|
1571 |
{
|
|
1572 |
if (interactive_mode) |
|
1573 |
return buffer_len(&output) < 16384; |
|
1574 |
else
|
|
1575 |
return buffer_len(&output) < 128 * 1024; |
|
1576 |
}
|
|
1577 |
||
1578 |
||
1579 |
static void |
|
1580 |
packet_set_tos(int interactive) |
|
1581 |
{
|
|
1582 |
#if defined(IP_TOS) && !defined(IP_TOS_IS_BROKEN)
|
|
1583 |
int tos = interactive ? IPTOS_LOWDELAY : IPTOS_THROUGHPUT; |
|
1584 |
||
1585 |
if (!packet_connection_is_on_socket() || |
|
1586 |
!packet_connection_is_ipv4()) |
|
1587 |
return; |
|
1588 |
if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, &tos, |
|
1589 |
sizeof(tos)) < 0) |
|
1590 |
error("setsockopt IP_TOS %d: %.100s:", |
|
1591 |
tos, strerror(errno)); |
|
1592 |
#endif
|
|
1593 |
}
|
|
1594 |
||
1595 |
/* Informs that the current session is interactive. Sets IP flags for that. */
|
|
1596 |
||
1597 |
void
|
|
1598 |
packet_set_interactive(int interactive) |
|
1599 |
{
|
|
1600 |
static int called = 0; |
|
1601 |
||
1602 |
if (called) |
|
1603 |
return; |
|
1604 |
called = 1; |
|
1605 |
||
1606 |
/* Record that we are in interactive mode. */
|
|
1607 |
interactive_mode = interactive; |
|
1608 |
||
1609 |
/* Only set socket options if using a socket. */
|
|
1610 |
if (!packet_connection_is_on_socket()) |
|
1611 |
return; |
|
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
1612 |
set_nodelay(connection_in); |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1613 |
packet_set_tos(interactive); |
1614 |
}
|
|
1615 |
||
1616 |
/* Returns true if the current connection is interactive. */
|
|
1617 |
||
1618 |
int
|
|
1619 |
packet_is_interactive(void) |
|
1620 |
{
|
|
1621 |
return interactive_mode; |
|
1622 |
}
|
|
1623 |
||
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
1624 |
int
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1625 |
packet_set_maxsize(u_int s) |
1626 |
{
|
|
1627 |
static int called = 0; |
|
1628 |
||
1629 |
if (called) { |
|
1630 |
logit("packet_set_maxsize: called twice: old %d new %d", |
|
1631 |
max_packet_size, s); |
|
1632 |
return -1; |
|
1633 |
}
|
|
1634 |
if (s < 4 * 1024 || s > 1024 * 1024) { |
|
1635 |
logit("packet_set_maxsize: bad size %d", s); |
|
1636 |
return -1; |
|
1637 |
}
|
|
1638 |
called = 1; |
|
1639 |
debug("packet_set_maxsize: setting to %d", s); |
|
1640 |
max_packet_size = s; |
|
1641 |
return s; |
|
1642 |
}
|
|
1643 |
||
1644 |
/* roundup current message to pad bytes */
|
|
1645 |
void
|
|
1646 |
packet_add_padding(u_char pad) |
|
1647 |
{
|
|
1648 |
extra_pad = pad; |
|
1649 |
}
|
|
1650 |
||
1651 |
/*
|
|
1652 |
* 9.2. Ignored Data Message
|
|
1653 |
*
|
|
1654 |
* byte SSH_MSG_IGNORE
|
|
1655 |
* string data
|
|
1656 |
*
|
|
1657 |
* All implementations MUST understand (and ignore) this message at any
|
|
1658 |
* time (after receiving the protocol version). No implementation is
|
|
1659 |
* required to send them. This message can be used as an additional
|
|
1660 |
* protection measure against advanced traffic analysis techniques.
|
|
1661 |
*/
|
|
1662 |
void
|
|
1663 |
packet_send_ignore(int nbytes) |
|
1664 |
{
|
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
1665 |
u_int32_t rnd = 0; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1666 |
int i; |
1667 |
||
1668 |
packet_start(compat20 ? SSH2_MSG_IGNORE : SSH_MSG_IGNORE); |
|
1669 |
packet_put_int(nbytes); |
|
1670 |
for (i = 0; i < nbytes; i++) { |
|
1671 |
if (i % 4 == 0) |
|
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
1672 |
rnd = arc4random(); |
1.13.1
by Colin Watson
Import upstream version 4.6p1 |
1673 |
packet_put_char((u_char)rnd & 0xff); |
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
1674 |
rnd >>= 8; |
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1675 |
}
|
1676 |
}
|
|
1677 |
||
1.1.1
by Colin Watson
Import upstream version 3.9p1 |
1678 |
#define MAX_PACKETS (1U<<31)
|
1
by Noah Meyerhans
Import upstream version 3.8.1p1 |
1679 |
int
|
1680 |
packet_need_rekeying(void) |
|
1681 |
{
|
|
1682 |
if (datafellows & SSH_BUG_NOREKEY) |
|
1683 |
return 0; |
|
1684 |
return
|
|
1685 |
(p_send.packets > MAX_PACKETS) || |
|
1686 |
(p_read.packets > MAX_PACKETS) || |
|
1687 |
(max_blocks_out && (p_send.blocks > max_blocks_out)) || |
|
1688 |
(max_blocks_in && (p_read.blocks > max_blocks_in)); |
|
1689 |
}
|
|
1690 |
||
1691 |
void
|
|
1692 |
packet_set_rekey_limit(u_int32_t bytes) |
|
1693 |
{
|
|
1694 |
rekey_limit = bytes; |
|
1695 |
}
|
|
1.1.3
by Colin Watson
Import upstream version 4.2p1 |
1696 |
|
1697 |
void
|
|
1698 |
packet_set_server(void) |
|
1699 |
{
|
|
1700 |
server_side = 1; |
|
1701 |
}
|
|
1702 |
||
1703 |
void
|
|
1704 |
packet_set_authenticated(void) |
|
1705 |
{
|
|
1706 |
after_authentication = 1; |
|
1707 |
}
|