1 /* $OpenBSD: packet.c,v 1.214 2015/08/20 22:32:42 deraadt Exp $ */
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,
34  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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"
41 
42 #ifdef WIN32
43 #include "winfixssh.h"
44 #endif
45 
46 #ifndef WIN32
47 #include <sys/param.h>	/* MIN roundup */
48 #endif
49 #include <sys/types.h>
50 #include "sys-queue.h"
51 #ifndef WIN32
52 #include <sys/socket.h>
53 #endif
54 #ifdef HAVE_SYS_TIME_H
55 # include <sys/time.h>
56 #endif
57 
58 #ifndef WIN32
59 #include <netinet/in.h>
60 #include <netinet/ip.h>
61 #include <arpa/inet.h>
62 #endif
63 
64 #include <errno.h>
65 #include <stdarg.h>
66 #include <stdio.h>
67 #include <stdlib.h>
68 #include <string.h>
69 #ifndef WIN32
70 #include <unistd.h>
71 #endif
72 #include <limits.h>
73 #include <signal.h>
74 #include <time.h>
75 
76 //#include <zlib.h>
77 
78 #include "buffer.h"	/* typedefs XXX */
79 #include "key.h"	/* typedefs XXX */
80 
81 #include "xmalloc.h"
82 #include "crc32.h"
83 #include "compat.h"
84 #include "ssh1.h"
85 #include "ssh2.h"
86 #include "cipher.h"
87 #include "sshkey.h"
88 #include "kex.h"
89 #include "digest.h"
90 #include "mac.h"
91 #include "log.h"
92 #include "canohost.h"
93 #include "misc.h"
94 #include "channels.h"
95 #include "ssh.h"
96 #include "packet.h"
97 #include "ssherr.h"
98 #include "sshbuf.h"
99 
100 #ifdef PACKET_DEBUG
101 #define DBG(x) x
102 #else
103 #define DBG(x)
104 #endif
105 
106 #define PACKET_MAX_SIZE (256 * 1024)
107 
108 #if 0
109 struct packet_state {
110 	u_int32_t seqnr;
111 	u_int32_t packets;
112 	u_int64_t blocks;
113 	u_int64_t bytes;
114 };
115 #endif
116 
117 struct packet {
118 	TAILQ_ENTRY(packet) next;
119 	u_char type;
120 	struct sshbuf *payload;
121 };
122 
123 struct session_state {
124 	/*
125 	 * This variable contains the file descriptors used for
126 	 * communicating with the other side.  connection_in is used for
127 	 * reading; connection_out for writing.  These can be the same
128 	 * descriptor, in which case it is assumed to be a socket.
129 	 */
130 	int connection_in;
131 	int connection_out;
132 
133 	/* Protocol flags for the remote side. */
134 	u_int remote_protocol_flags;
135 
136 	/* Encryption context for receiving data.  Only used for decryption. */
137 	struct sshcipher_ctx receive_context;
138 
139 	/* Encryption context for sending data.  Only used for encryption. */
140 	struct sshcipher_ctx send_context;
141 
142 	/* Buffer for raw input data from the socket. */
143 	struct sshbuf *input;
144 
145 	/* Buffer for raw output data going to the socket. */
146 	struct sshbuf *output;
147 
148 	/* Buffer for the partial outgoing packet being constructed. */
149 	struct sshbuf *outgoing_packet;
150 
151 	/* Buffer for the incoming packet currently being processed. */
152 	struct sshbuf *incoming_packet;
153 
154 	/* Scratch buffer for packet compression/decompression. */
155 	struct sshbuf *compression_buffer;
156 
157 	/* Incoming/outgoing compression dictionaries */
158 	//z_stream compression_in_stream;
159 	//z_stream compression_out_stream;
160 	int compression_in_started;
161 	int compression_out_started;
162 	int compression_in_failures;
163 	int compression_out_failures;
164 
165 	/*
166 	 * Flag indicating whether packet compression/decompression is
167 	 * enabled.
168 	 */
169 	int packet_compression;
170 
171 	/* default maximum packet size */
172 	u_int max_packet_size;
173 
174 	/* Flag indicating whether this module has been initialized. */
175 	int initialized;
176 
177 	/* Set to true if the connection is interactive. */
178 	int interactive_mode;
179 
180 	/* Set to true if we are the server side. */
181 	int server_side;
182 
183 	/* Set to true if we are authenticated. */
184 	int after_authentication;
185 
186 	int keep_alive_timeouts;
187 
188 	/* The maximum time that we will wait to send or receive a packet */
189 	int packet_timeout_ms;
190 
191 	/* Session key information for Encryption and MAC */
192 	struct newkeys *newkeys[MODE_MAX];
193 	//struct packet_state p_read, p_send;
194 
195 	/* Volume-based rekeying */
196 	u_int64_t max_blocks_in, max_blocks_out;
197 	u_int32_t rekey_limit;
198 
199 	/* Time-based rekeying */
200 	u_int32_t rekey_interval;	/* how often in seconds */
201 	time_t rekey_time;	/* time of last rekeying */
202 
203 	/* Session key for protocol v1 */
204 	u_char ssh1_key[SSH_SESSION_KEY_LENGTH];
205 	u_int ssh1_keylen;
206 
207 	/* roundup current message to extra_pad bytes */
208 	u_char extra_pad;
209 
210 	/* XXX discard incoming data after MAC error */
211 	u_int packet_discard;
212 	struct sshmac *packet_discard_mac;
213 
214 	/* Used in packet_read_poll2() */
215 	u_int packlen;
216 
217 	/* Used in packet_send2 */
218 	int rekeying;
219 
220 	/* Used in packet_set_interactive */
221 	int set_interactive_called;
222 
223 	/* Used in packet_set_maxsize */
224 	int set_maxsize_called;
225 
226 	/* One-off warning about weak ciphers */
227 	int cipher_warning_done;
228 
229 	/* SSH1 CRC compensation attack detector */
230 	//struct deattack_ctx deattack;
231 
232 	TAILQ_HEAD(, packet) outgoing;
233 };
234 
235 
236 #if 0
237 struct ssh *
238 ssh_alloc_session_state(void)
239 {
240 	struct ssh *ssh = NULL;
241 	struct session_state *state = NULL;
242 
243 	if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
244 	    (state = calloc(1, sizeof(*state))) == NULL ||
245 	    (state->input = sshbuf_new()) == NULL ||
246 	    (state->output = sshbuf_new()) == NULL ||
247 	    (state->outgoing_packet = sshbuf_new()) == NULL ||
248 	    (state->incoming_packet = sshbuf_new()) == NULL)
249 		goto fail;
250 	TAILQ_INIT(&state->outgoing);
251 	TAILQ_INIT(&ssh->private_keys);
252 	TAILQ_INIT(&ssh->public_keys);
253 	state->connection_in = -1;
254 	state->connection_out = -1;
255 	state->max_packet_size = 32768;
256 	state->packet_timeout_ms = -1;
257 	state->p_send.packets = state->p_read.packets = 0;
258 	state->initialized = 1;
259 	/*
260 	 * ssh_packet_send2() needs to queue packets until
261 	 * we've done the initial key exchange.
262 	 */
263 	state->rekeying = 1;
264 	ssh->state = state;
265 	return ssh;
266  fail:
267 	if (state) {
268 		sshbuf_free(state->input);
269 		sshbuf_free(state->output);
270 		sshbuf_free(state->incoming_packet);
271 		sshbuf_free(state->outgoing_packet);
272 		free(state);
273 	}
274 	free(ssh);
275 	return NULL;
276 }
277 #endif
278 
279 
280 /*
281  * Sets the descriptors used for communication.  Disables encryption until
282  * packet_set_encryption_key is called.
283  */
284 int
ssh_packet_set_connection(ncrack_ssh_state * nstate)285 ssh_packet_set_connection(ncrack_ssh_state *nstate)
286 {
287 	//struct session_state *state;
288 	const struct sshcipher *none = cipher_by_name("none");
289 	int r;
290 
291 	if (none == NULL) {
292 		ssh_error("%s: cannot load cipher 'none'", __func__);
293 		return -1;
294 	}
295 
296 #if 0
297 	if (ssh == NULL)
298 		ssh = ssh_alloc_session_state();
299 	if (ssh == NULL) {
300 		ssh_error("%s: cound not allocate state", __func__);
301 		return NULL;
302 	}
303 #endif
304 
305   nstate->input = sshbuf_new();
306   nstate->output = sshbuf_new();
307   nstate->outgoing_packet = sshbuf_new();
308   nstate->incoming_packet = sshbuf_new();
309   nstate->p_send.packets = nstate->p_read.packets = 0;
310 
311 	//state = ssh->state;
312 	//state->connection_in = fd_in;
313 	//state->connection_out = fd_out;
314 	if ((r = cipher_init(&nstate->send_context, none,
315 	    (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
316 	    (r = cipher_init(&nstate->receive_context, none,
317 	    (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
318 		ssh_error("%s: cipher_init failed: %s", __func__, ssh_err(r));
319 		//free(ssh);
320 		return -1;
321 	}
322 	nstate->newkeys[MODE_IN] = nstate->newkeys[MODE_OUT] = NULL;
323 	//deattack_init(&nstate->deattack);
324 	/*
325 	 * Cache the IP address of the remote connection for use in error
326 	 * messages that might be generated after the connection has closed.
327 	 */
328 	//(void)ssh_remote_ipaddr(ssh);
329 	//return ssh;
330   return 0;
331 }
332 
333 
334 void
ssh_packet_set_timeout(struct ssh * ssh,int timeout,int count)335 ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
336 {
337 	struct session_state *state = ssh->state;
338 
339 	if (timeout <= 0 || count <= 0) {
340 		state->packet_timeout_ms = -1;
341 		return;
342 	}
343 	if ((INT_MAX / 1000) / count < timeout)
344 		state->packet_timeout_ms = INT_MAX;
345 	else
346 		state->packet_timeout_ms = timeout * count * 1000;
347 }
348 
349 int
ssh_packet_stop_discard(ncrack_ssh_state * nstate)350 ssh_packet_stop_discard(ncrack_ssh_state *nstate)
351 {
352 	//struct session_state *state = ssh->state;
353 	int r;
354 
355 	if (nstate->packet_discard_mac) {
356 		char buf[1024];
357 
358 		memset(buf, 'a', sizeof(buf));
359 		while (sshbuf_len(nstate->incoming_packet) <
360 		    PACKET_MAX_SIZE)
361 			if ((r = sshbuf_put(nstate->incoming_packet, buf,
362 			    sizeof(buf))) != 0)
363 				return r;
364 		(void) mac_compute(nstate->packet_discard_mac,
365 		    nstate->p_read.seqnr,
366 		    sshbuf_ptr(nstate->incoming_packet), PACKET_MAX_SIZE,
367 		    NULL, 0);
368 	}
369 	//logit("Finished discarding for %.200s", ssh_remote_ipaddr(ssh));
370 	return SSH_ERR_MAC_INVALID;
371 }
372 
373 static int
ssh_packet_start_discard(ncrack_ssh_state * nstate,struct sshenc * enc,struct sshmac * mac,u_int packet_length,u_int discard)374 ssh_packet_start_discard(ncrack_ssh_state *nstate, struct sshenc *enc,
375     struct sshmac *mac, u_int packet_length, u_int discard)
376 {
377 	//struct session_state *state = ssh->state;
378 	int r;
379 
380 	if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
381 		if ((r = sshpkt_disconnect(nstate, "Packet corrupt")) != 0)
382 			return r;
383 		return SSH_ERR_MAC_INVALID;
384 	}
385 	if (packet_length != PACKET_MAX_SIZE && mac && mac->enabled)
386 		nstate->packet_discard_mac = mac;
387 	if (sshbuf_len(nstate->input) >= discard &&
388 	   (r = ssh_packet_stop_discard(nstate)) != 0)
389 		return r;
390 	nstate->packet_discard = discard - sshbuf_len(nstate->input);
391 	return 0;
392 }
393 
394 /* Returns 1 if remote host is connected via socket, 0 if not. */
395 
396 int
ssh_packet_connection_is_on_socket(struct ssh * ssh)397 ssh_packet_connection_is_on_socket(struct ssh *ssh)
398 {
399 #if 0
400 	struct session_state *state = ssh->state;
401 	struct sockaddr_storage from, to;
402 	socklen_t fromlen, tolen;
403 
404 	/* filedescriptors in and out are the same, so it's a socket */
405 	if (state->connection_in == state->connection_out)
406 		return 1;
407 	fromlen = sizeof(from);
408 	memset(&from, 0, sizeof(from));
409 	if (getpeername(state->connection_in, (struct sockaddr *)&from,
410 	    &fromlen) < 0)
411 		return 0;
412 	tolen = sizeof(to);
413 	memset(&to, 0, sizeof(to));
414 	if (getpeername(state->connection_out, (struct sockaddr *)&to,
415 	    &tolen) < 0)
416 		return 0;
417 	if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
418 		return 0;
419 	if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
420 		return 0;
421 #endif
422 	return 1;
423 }
424 
425 
426 void
ssh_packet_get_bytes(struct ssh * ssh,u_int64_t * ibytes,u_int64_t * obytes)427 ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
428 {
429 #if 0
430 	if (ibytes)
431 		*ibytes = ssh->state->p_read.bytes;
432 	if (obytes)
433 		*obytes = ssh->state->p_send.bytes;
434 #endif
435 }
436 
437 int
ssh_packet_connection_af(struct ssh * ssh)438 ssh_packet_connection_af(struct ssh *ssh)
439 {
440 #if 0
441 	struct sockaddr_storage to;
442 	socklen_t tolen = sizeof(to);
443 
444 	memset(&to, 0, sizeof(to));
445 	if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
446 	    &tolen) < 0)
447 		return 0;
448 #ifdef IPV4_IN_IPV6
449 	if (to.ss_family == AF_INET6 &&
450 	    IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr))
451 		return AF_INET;
452 #endif
453 	return to.ss_family;
454 #endif
455   return -1; // temp
456 }
457 
458 /* Sets the connection into non-blocking mode. */
459 
460 #if 0
461 void
462 ssh_packet_set_nonblocking(struct ssh *ssh)
463 {
464 	/* Set the socket into non-blocking mode. */
465 	set_nonblock(ssh->state->connection_in);
466 
467 	if (ssh->state->connection_out != ssh->state->connection_in)
468 		set_nonblock(ssh->state->connection_out);
469 }
470 #endif
471 
472 /* Returns the socket used for reading. */
473 
474 int
ssh_packet_get_connection_in(struct ssh * ssh)475 ssh_packet_get_connection_in(struct ssh *ssh)
476 {
477 	return ssh->state->connection_in;
478 }
479 
480 /* Returns the descriptor used for writing. */
481 
482 int
ssh_packet_get_connection_out(struct ssh * ssh)483 ssh_packet_get_connection_out(struct ssh *ssh)
484 {
485 	return ssh->state->connection_out;
486 }
487 
488 /*
489  * Returns the IP-address of the remote host as a string.  The returned
490  * string must not be freed.
491  */
492 
493 const char *
ssh_remote_ipaddr(struct ssh * ssh)494 ssh_remote_ipaddr(struct ssh *ssh)
495 {
496 #if 0
497 	/* Check whether we have cached the ipaddr. */
498 	if (ssh->remote_ipaddr == NULL)
499 		ssh->remote_ipaddr = ssh_packet_connection_is_on_socket(ssh) ?
500 		    get_peer_ipaddr(ssh->state->connection_in) :
501 		    strdup("UNKNOWN");
502 	if (ssh->remote_ipaddr == NULL)
503 		return "UNKNOWN";
504 	return ssh->remote_ipaddr;
505 #endif
506   return NULL; // temp
507 }
508 
509 /* Closes the connection and clears and frees internal data structures. */
510 
511 void
ssh_packet_close(struct ssh * ssh)512 ssh_packet_close(struct ssh *ssh)
513 {
514 #if 0
515 	struct session_state *state = ssh->state;
516 	int r;
517 	u_int mode;
518 
519 	if (!state->initialized)
520 		return;
521 	state->initialized = 0;
522 	if (state->connection_in == state->connection_out) {
523 		shutdown(state->connection_out, SHUT_RDWR);
524 		close(state->connection_out);
525 	} else {
526 		close(state->connection_in);
527 		close(state->connection_out);
528 	}
529 	sshbuf_free(state->input);
530 	sshbuf_free(state->output);
531 	sshbuf_free(state->outgoing_packet);
532 	sshbuf_free(state->incoming_packet);
533 	for (mode = 0; mode < MODE_MAX; mode++)
534 		kex_free_newkeys(state->newkeys[mode]);
535 	if (state->compression_buffer) {
536 #if 0
537 		sshbuf_free(state->compression_buffer);
538 		if (state->compression_out_started) {
539 			z_streamp stream = &state->compression_out_stream;
540 			debug("compress outgoing: "
541 			    "raw data %llu, compressed %llu, factor %.2f",
542 				(unsigned long long)stream->total_in,
543 				(unsigned long long)stream->total_out,
544 				stream->total_in == 0 ? 0.0 :
545 				(double) stream->total_out / stream->total_in);
546 			if (state->compression_out_failures == 0)
547 				deflateEnd(stream);
548 		}
549 		if (state->compression_in_started) {
550 			z_streamp stream = &state->compression_out_stream;
551 			debug("compress incoming: "
552 			    "raw data %llu, compressed %llu, factor %.2f",
553 			    (unsigned long long)stream->total_out,
554 			    (unsigned long long)stream->total_in,
555 			    stream->total_out == 0 ? 0.0 :
556 			    (double) stream->total_in / stream->total_out);
557 			if (state->compression_in_failures == 0)
558 				inflateEnd(stream);
559 		}
560 #endif
561 	}
562 	if ((r = cipher_cleanup(&state->send_context)) != 0)
563 		ssh_error("%s: cipher_cleanup failed: %s", __func__, ssh_err(r));
564 	if ((r = cipher_cleanup(&state->receive_context)) != 0)
565 		ssh_error("%s: cipher_cleanup failed: %s", __func__, ssh_err(r));
566 	if (ssh->remote_ipaddr) {
567 		free(ssh->remote_ipaddr);
568 		ssh->remote_ipaddr = NULL;
569 	}
570 	free(ssh->state);
571 	ssh->state = NULL;
572 #endif
573 }
574 
575 /* Sets remote side protocol flags. */
576 
577 void
ssh_packet_set_protocol_flags(struct ssh * ssh,u_int protocol_flags)578 ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
579 {
580 	ssh->state->remote_protocol_flags = protocol_flags;
581 }
582 
583 /* Returns the remote protocol flags set earlier by the above function. */
584 
585 u_int
ssh_packet_get_protocol_flags(struct ssh * ssh)586 ssh_packet_get_protocol_flags(struct ssh *ssh)
587 {
588 	return ssh->state->remote_protocol_flags;
589 }
590 
591 
592 #if 0
593 /*
594  * Starts packet compression from the next packet on in both directions.
595  * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
596  */
597 
598 static int
599 ssh_packet_init_compression(struct ssh *ssh)
600 {
601 	if (!ssh->state->compression_buffer &&
602 	   ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
603 		return SSH_ERR_ALLOC_FAIL;
604 	return 0;
605 }
606 
607 static int
608 start_compression_out(struct ssh *ssh, int level)
609 {
610 	if (level < 1 || level > 9)
611 		return SSH_ERR_INVALID_ARGUMENT;
612 	debug("Enabling compression at level %d.", level);
613 	if (ssh->state->compression_out_started == 1)
614 		deflateEnd(&ssh->state->compression_out_stream);
615 	switch (deflateInit(&ssh->state->compression_out_stream, level)) {
616 	case Z_OK:
617 		ssh->state->compression_out_started = 1;
618 		break;
619 	case Z_MEM_ERROR:
620 		return SSH_ERR_ALLOC_FAIL;
621 	default:
622 		return SSH_ERR_INTERNAL_ERROR;
623 	}
624 	return 0;
625 }
626 
627 static int
628 start_compression_in(struct ssh *ssh)
629 {
630 	if (ssh->state->compression_in_started == 1)
631 		inflateEnd(&ssh->state->compression_in_stream);
632 	switch (inflateInit(&ssh->state->compression_in_stream)) {
633 	case Z_OK:
634 		ssh->state->compression_in_started = 1;
635 		break;
636 	case Z_MEM_ERROR:
637 		return SSH_ERR_ALLOC_FAIL;
638 	default:
639 		return SSH_ERR_INTERNAL_ERROR;
640 	}
641 	return 0;
642 }
643 
644 int
645 ssh_packet_start_compression(struct ssh *ssh, int level)
646 {
647 	int r;
648 
649 	if (ssh->state->packet_compression && !compat20)
650 		return SSH_ERR_INTERNAL_ERROR;
651 	ssh->state->packet_compression = 1;
652 	if ((r = ssh_packet_init_compression(ssh)) != 0 ||
653 	    (r = start_compression_in(ssh)) != 0 ||
654 	    (r = start_compression_out(ssh, level)) != 0)
655 		return r;
656 	return 0;
657 }
658 
659 /* XXX remove need for separate compression buffer */
660 static int
661 compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
662 {
663 	u_char buf[4096];
664 	int r, status;
665 
666 	if (ssh->state->compression_out_started != 1)
667 		return SSH_ERR_INTERNAL_ERROR;
668 
669 	/* This case is not handled below. */
670 	if (sshbuf_len(in) == 0)
671 		return 0;
672 
673 	/* Input is the contents of the input buffer. */
674 	if ((ssh->state->compression_out_stream.next_in =
675 	    sshbuf_mutable_ptr(in)) == NULL)
676 		return SSH_ERR_INTERNAL_ERROR;
677 	ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
678 
679 	/* Loop compressing until deflate() returns with avail_out != 0. */
680 	do {
681 		/* Set up fixed-size output buffer. */
682 		ssh->state->compression_out_stream.next_out = buf;
683 		ssh->state->compression_out_stream.avail_out = sizeof(buf);
684 
685 		/* Compress as much data into the buffer as possible. */
686 		status = deflate(&ssh->state->compression_out_stream,
687 		    Z_PARTIAL_FLUSH);
688 		switch (status) {
689 		case Z_MEM_ERROR:
690 			return SSH_ERR_ALLOC_FAIL;
691 		case Z_OK:
692 			/* Append compressed data to output_buffer. */
693 			if ((r = sshbuf_put(out, buf, sizeof(buf) -
694 			    ssh->state->compression_out_stream.avail_out)) != 0)
695 				return r;
696 			break;
697 		case Z_STREAM_ERROR:
698 		default:
699 			ssh->state->compression_out_failures++;
700 			return SSH_ERR_INVALID_FORMAT;
701 		}
702 	} while (ssh->state->compression_out_stream.avail_out == 0);
703 	return 0;
704 }
705 
706 static int
707 uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
708 {
709 	u_char buf[4096];
710 	int r, status;
711 
712 	if (ssh->state->compression_in_started != 1)
713 		return SSH_ERR_INTERNAL_ERROR;
714 
715 	if ((ssh->state->compression_in_stream.next_in =
716 	    sshbuf_mutable_ptr(in)) == NULL)
717 		return SSH_ERR_INTERNAL_ERROR;
718 	ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
719 
720 	for (;;) {
721 		/* Set up fixed-size output buffer. */
722 		ssh->state->compression_in_stream.next_out = buf;
723 		ssh->state->compression_in_stream.avail_out = sizeof(buf);
724 
725 		status = inflate(&ssh->state->compression_in_stream,
726 		    Z_PARTIAL_FLUSH);
727 		switch (status) {
728 		case Z_OK:
729 			if ((r = sshbuf_put(out, buf, sizeof(buf) -
730 			    ssh->state->compression_in_stream.avail_out)) != 0)
731 				return r;
732 			break;
733 		case Z_BUF_ERROR:
734 			/*
735 			 * Comments in zlib.h say that we should keep calling
736 			 * inflate() until we get an error.  This appears to
737 			 * be the error that we get.
738 			 */
739 			return 0;
740 		case Z_DATA_ERROR:
741 			return SSH_ERR_INVALID_FORMAT;
742 		case Z_MEM_ERROR:
743 			return SSH_ERR_ALLOC_FAIL;
744 		case Z_STREAM_ERROR:
745 		default:
746 			ssh->state->compression_in_failures++;
747 			return SSH_ERR_INTERNAL_ERROR;
748 		}
749 	}
750 	/* NOTREACHED */
751 }
752 
753 /* Serialise compression state into a blob for privsep */
754 static int
755 ssh_packet_get_compress_state(struct sshbuf *m, struct ssh *ssh)
756 {
757 	struct session_state *state = ssh->state;
758 	struct sshbuf *b;
759 	int r;
760 
761 	if ((b = sshbuf_new()) == NULL)
762 		return SSH_ERR_ALLOC_FAIL;
763 	if (state->compression_in_started) {
764 		if ((r = sshbuf_put_string(b, &state->compression_in_stream,
765 		    sizeof(state->compression_in_stream))) != 0)
766 			goto out;
767 	} else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
768 		goto out;
769 	if (state->compression_out_started) {
770 		if ((r = sshbuf_put_string(b, &state->compression_out_stream,
771 		    sizeof(state->compression_out_stream))) != 0)
772 			goto out;
773 	} else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
774 		goto out;
775 	r = sshbuf_put_stringb(m, b);
776  out:
777 	sshbuf_free(b);
778 	return r;
779 }
780 
781 /* Deserialise compression state from a blob for privsep */
782 static int
783 ssh_packet_set_compress_state(struct ssh *ssh, struct sshbuf *m)
784 {
785 	struct session_state *state = ssh->state;
786 	struct sshbuf *b = NULL;
787 	int r;
788 	const u_char *inblob, *outblob;
789 	size_t inl, outl;
790 
791 	if ((r = sshbuf_froms(m, &b)) != 0)
792 		goto out;
793 	if ((r = sshbuf_get_string_direct(b, &inblob, &inl)) != 0 ||
794 	    (r = sshbuf_get_string_direct(b, &outblob, &outl)) != 0)
795 		goto out;
796 	if (inl == 0)
797 		state->compression_in_started = 0;
798 	else if (inl != sizeof(state->compression_in_stream)) {
799 		r = SSH_ERR_INTERNAL_ERROR;
800 		goto out;
801 	} else {
802 		state->compression_in_started = 1;
803 		memcpy(&state->compression_in_stream, inblob, inl);
804 	}
805 	if (outl == 0)
806 		state->compression_out_started = 0;
807 	else if (outl != sizeof(state->compression_out_stream)) {
808 		r = SSH_ERR_INTERNAL_ERROR;
809 		goto out;
810 	} else {
811 		state->compression_out_started = 1;
812 		memcpy(&state->compression_out_stream, outblob, outl);
813 	}
814 	r = 0;
815  out:
816 	sshbuf_free(b);
817 	return r;
818 }
819 
820 void
821 ssh_packet_set_compress_hooks(struct ssh *ssh, void *ctx,
822     void *(*allocfunc)(void *, u_int, u_int),
823     void (*freefunc)(void *, void *))
824 {
825 	ssh->state->compression_out_stream.zalloc = (alloc_func)allocfunc;
826 	ssh->state->compression_out_stream.zfree = (free_func)freefunc;
827 	ssh->state->compression_out_stream.opaque = ctx;
828 	ssh->state->compression_in_stream.zalloc = (alloc_func)allocfunc;
829 	ssh->state->compression_in_stream.zfree = (free_func)freefunc;
830 	ssh->state->compression_in_stream.opaque = ctx;
831 }
832 #endif
833 
834 
835 /*
836  * Causes any further packets to be encrypted using the given key.  The same
837  * key is used for both sending and reception.  However, both directions are
838  * encrypted independently of each other.
839  */
840 
841 void
ssh_packet_set_encryption_key(struct ssh * ssh,const u_char * key,u_int keylen,int number)842 ssh_packet_set_encryption_key(struct ssh *ssh, const u_char *key, u_int keylen, int number)
843 {
844 #ifndef WITH_SSH1
845 	fatal("no SSH protocol 1 support");
846 #else /* WITH_SSH1 */
847 	struct session_state *state = ssh->state;
848 	const struct sshcipher *cipher = cipher_by_number(number);
849 	int r;
850 	const char *wmsg;
851 
852 	if (cipher == NULL)
853 		fatal("%s: unknown cipher number %d", __func__, number);
854 	if (keylen < 20)
855 		fatal("%s: keylen too small: %d", __func__, keylen);
856 	if (keylen > SSH_SESSION_KEY_LENGTH)
857 		fatal("%s: keylen too big: %d", __func__, keylen);
858 	memcpy(state->ssh1_key, key, keylen);
859 	state->ssh1_keylen = keylen;
860 	if ((r = cipher_init(&state->send_context, cipher, key, keylen,
861 	    NULL, 0, CIPHER_ENCRYPT)) != 0 ||
862 	    (r = cipher_init(&state->receive_context, cipher, key, keylen,
863 	    NULL, 0, CIPHER_DECRYPT) != 0))
864 		fatal("%s: cipher_init failed: %s", __func__, ssh_err(r));
865 	if (!state->cipher_warning_done &&
866 	    ((wmsg = cipher_warning_message(&state->send_context)) != NULL ||
867 	    (wmsg = cipher_warning_message(&state->send_context)) != NULL)) {
868 		ssh_error("Warning: %s", wmsg);
869 		state->cipher_warning_done = 1;
870 	}
871 #endif /* WITH_SSH1 */
872 }
873 
874 /*
875  * Finalizes and sends the packet.  If the encryption key has been set,
876  * encrypts the packet before sending.
877  */
878 
879 int
ssh_packet_send1(ncrack_ssh_state * nstate)880 ssh_packet_send1(ncrack_ssh_state *nstate)
881 {
882 	//struct session_state *state = ssh->state;
883 	u_char buf[8], *cp;
884 	int r, padding, len;
885 	u_int checksum;
886 
887 	/*
888 	 * If using packet compression, compress the payload of the outgoing
889 	 * packet.
890 	 */
891 #if 0
892 	if (nstate->packet_compression) {
893 		sshbuf_reset(nstate->compression_buffer);
894 		/* Skip padding. */
895 		if ((r = sshbuf_consume(nstate->outgoing_packet, 8)) != 0)
896 			goto out;
897 		/* padding */
898 		if ((r = sshbuf_put(nstate->compression_buffer,
899 		    "\0\0\0\0\0\0\0\0", 8)) != 0)
900 			goto out;
901 		if ((r = compress_buffer(ssh, nstate->outgoing_packet,
902 		    nstate->compression_buffer)) != 0)
903 			goto out;
904 		sshbuf_reset(nstate->outgoing_packet);
905                 if ((r = sshbuf_putb(nstate->outgoing_packet,
906                     nstate->compression_buffer)) != 0)
907 			goto out;
908 	}
909 #endif
910 	/* Compute packet length without padding (add checksum, remove padding). */
911 	len = sshbuf_len(nstate->outgoing_packet) + 4 - 8;
912 
913 	/* Insert padding. Initialized to zero in packet_start1() */
914 	padding = 8 - len % 8;
915 	if (!nstate->send_context.plaintext) {
916 		cp = sshbuf_mutable_ptr(nstate->outgoing_packet);
917 		if (cp == NULL) {
918 			r = SSH_ERR_INTERNAL_ERROR;
919 			goto out;
920 		}
921 		arc4random_buf(cp + 8 - padding, padding);
922 	}
923 	if ((r = sshbuf_consume(nstate->outgoing_packet, 8 - padding)) != 0)
924 		goto out;
925 
926 	/* Add check bytes. */
927 	checksum = ssh_crc32(sshbuf_ptr(nstate->outgoing_packet),
928 	    sshbuf_len(nstate->outgoing_packet));
929 	POKE_U32(buf, checksum);
930 	if ((r = sshbuf_put(nstate->outgoing_packet, buf, 4)) != 0)
931 		goto out;
932 
933 #ifdef PACKET_DEBUG
934 	fprintf(stderr, "packet_send plain: ");
935 	sshbuf_dump(nstate->outgoing_packet, stderr);
936 #endif
937 
938 	/* Append to output. */
939 	POKE_U32(buf, len);
940 	if ((r = sshbuf_put(nstate->output, buf, 4)) != 0)
941 		goto out;
942 	if ((r = sshbuf_reserve(nstate->output,
943 	    sshbuf_len(nstate->outgoing_packet), &cp)) != 0)
944 		goto out;
945 	if ((r = cipher_crypt(&nstate->send_context, 0, cp,
946 	    sshbuf_ptr(nstate->outgoing_packet),
947 	    sshbuf_len(nstate->outgoing_packet), 0, 0)) != 0)
948 		goto out;
949 
950 #ifdef PACKET_DEBUG
951 	fprintf(stderr, "encrypted: ");
952 	sshbuf_dump(nstate->output, stderr);
953 #endif
954 	nstate->p_send.packets++;
955 	nstate->p_send.bytes += len +
956 	    sshbuf_len(nstate->outgoing_packet);
957 	sshbuf_reset(nstate->outgoing_packet);
958 
959 	/*
960 	 * Note that the packet is now only buffered in output.  It won't be
961 	 * actually sent until ssh_packet_write_wait or ssh_packet_write_poll
962 	 * is called.
963 	 */
964 	r = 0;
965  out:
966 	return r;
967 }
968 
969 int
ssh_set_newkeys(ncrack_ssh_state * nstate,int mode)970 ssh_set_newkeys(ncrack_ssh_state *nstate, int mode)
971 {
972 	//struct session_state *state = ssh->state;
973 	struct sshenc *enc;
974 	struct sshmac *mac;
975 	struct sshcomp *comp;
976 	struct sshcipher_ctx *cc;
977 	u_int64_t *max_blocks;
978 	const char *wmsg;
979 	int r, crypt_type;
980 
981 	debug2("set_newkeys: mode %d", mode);
982 
983 	if (mode == MODE_OUT) {
984 		cc = &nstate->send_context;
985 		crypt_type = CIPHER_ENCRYPT;
986 		nstate->p_send.packets = nstate->p_send.blocks = 0;
987 		max_blocks = &nstate->max_blocks_out;
988 	} else {
989 		cc = &nstate->receive_context;
990 		crypt_type = CIPHER_DECRYPT;
991 		nstate->p_read.packets = nstate->p_read.blocks = 0;
992 		max_blocks = &nstate->max_blocks_in;
993 	}
994 	if (nstate->newkeys[mode] != NULL) {
995 		debug("set_newkeys: rekeying");
996 		if ((r = cipher_cleanup(cc)) != 0)
997 			return r;
998 		enc  = &nstate->newkeys[mode]->enc;
999 		mac  = &nstate->newkeys[mode]->mac;
1000 		comp = &nstate->newkeys[mode]->comp;
1001 		mac_clear(mac);
1002 		explicit_bzero(enc->iv,  enc->iv_len);
1003 		explicit_bzero(enc->key, enc->key_len);
1004 		explicit_bzero(mac->key, mac->key_len);
1005 		free(enc->name);
1006 		free(enc->iv);
1007 		free(enc->key);
1008 		free(mac->name);
1009 		free(mac->key);
1010 		free(comp->name);
1011 		free(nstate->newkeys[mode]);
1012 	}
1013 	/* move newkeys from kex to state */
1014 	if ((nstate->newkeys[mode] = nstate->kex->newkeys[mode]) == NULL)
1015 		return SSH_ERR_INTERNAL_ERROR;
1016 	nstate->kex->newkeys[mode] = NULL;
1017 	enc  = &nstate->newkeys[mode]->enc;
1018 	mac  = &nstate->newkeys[mode]->mac;
1019 	comp = &nstate->newkeys[mode]->comp;
1020 	if (cipher_authlen(enc->cipher) == 0) {
1021 		if ((r = mac_init(mac)) != 0)
1022 			return r;
1023 	}
1024 	mac->enabled = 1;
1025 	DBG(debug("cipher_init_context: %d", mode));
1026 	if ((r = cipher_init(cc, enc->cipher, enc->key, enc->key_len,
1027 	    enc->iv, enc->iv_len, crypt_type)) != 0)
1028 		return r;
1029 	if (!nstate->cipher_warning_done &&
1030 	    (wmsg = cipher_warning_message(cc)) != NULL) {
1031 		ssh_error("Warning: %s", wmsg);
1032 		nstate->cipher_warning_done = 1;
1033 	}
1034 	/* Deleting the keys does not gain extra security */
1035 	/* explicit_bzero(enc->iv,  enc->block_size);
1036 	   explicit_bzero(enc->key, enc->key_len);
1037 	   explicit_bzero(mac->key, mac->key_len); */
1038 
1039 #if 0
1040 	if ((comp->type == COMP_ZLIB ||
1041 	    (comp->type == COMP_DELAYED &&
1042 	     state->after_authentication)) && comp->enabled == 0) {
1043 		if ((r = ssh_packet_init_compression(ssh)) < 0)
1044 			return r;
1045 		if (mode == MODE_OUT) {
1046 			if ((r = start_compression_out(ssh, 6)) != 0)
1047 				return r;
1048 		} else {
1049 			if ((r = start_compression_in(ssh)) != 0)
1050 				return r;
1051 		}
1052 		comp->enabled = 1;
1053 	}
1054 #endif
1055 	/*
1056 	 * The 2^(blocksize*2) limit is too expensive for 3DES,
1057 	 * blowfish, etc, so enforce a 1GB limit for small blocksizes.
1058 	 */
1059 	if (enc->block_size >= 16)
1060 		*max_blocks = (u_int64_t)1 << (enc->block_size*2);
1061 	else
1062 		*max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1063 	if (nstate->rekey_limit)
1064 		*max_blocks = MIN(*max_blocks,
1065 		    nstate->rekey_limit / enc->block_size);
1066 	return 0;
1067 }
1068 
1069 
1070 #if 0
1071 /*
1072  * Delayed compression for SSH2 is enabled after authentication:
1073  * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1074  * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
1075  */
1076 static int
1077 ssh_packet_enable_delayed_compress(struct ssh *ssh)
1078 {
1079 	struct session_state *state = ssh->state;
1080 	struct sshcomp *comp = NULL;
1081 	int r, mode;
1082 
1083 	/*
1084 	 * Remember that we are past the authentication step, so rekeying
1085 	 * with COMP_DELAYED will turn on compression immediately.
1086 	 */
1087 	state->after_authentication = 1;
1088 	for (mode = 0; mode < MODE_MAX; mode++) {
1089 		/* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1090 		if (state->newkeys[mode] == NULL)
1091 			continue;
1092 		comp = &state->newkeys[mode]->comp;
1093 		if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1094 			if ((r = ssh_packet_init_compression(ssh)) != 0)
1095 				return r;
1096 			if (mode == MODE_OUT) {
1097 				if ((r = start_compression_out(ssh, 6)) != 0)
1098 					return r;
1099 			} else {
1100 				if ((r = start_compression_in(ssh)) != 0)
1101 					return r;
1102 			}
1103 			comp->enabled = 1;
1104 		}
1105 	}
1106 	return 0;
1107 }
1108 #endif
1109 
1110 
1111 /*
1112  * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1113  */
1114 int
ssh_packet_send2_wrapped(ncrack_ssh_state * nstate)1115 ssh_packet_send2_wrapped(ncrack_ssh_state *nstate)
1116 {
1117 	//struct session_state *state = ssh->state;
1118 	u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1119 	u_char padlen, pad = 0;
1120 	u_int authlen = 0, aadlen = 0;
1121 	u_int len;
1122 	struct sshenc *enc   = NULL;
1123 	struct sshmac *mac   = NULL;
1124 	struct sshcomp *comp = NULL;
1125 	int r, block_size;
1126 
1127 	if (nstate->newkeys[MODE_OUT] != NULL) {
1128 		enc  = &nstate->newkeys[MODE_OUT]->enc;
1129 		mac  = &nstate->newkeys[MODE_OUT]->mac;
1130 		comp = &nstate->newkeys[MODE_OUT]->comp;
1131 		/* disable mac for authenticated encryption */
1132 		if ((authlen = cipher_authlen(enc->cipher)) != 0)
1133 			mac = NULL;
1134 	}
1135 	block_size = enc ? enc->block_size : 8;
1136 	aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1137 
1138 	type = (sshbuf_ptr(nstate->outgoing_packet))[5];
1139 
1140 #ifdef PACKET_DEBUG
1141 	fprintf(stderr, "plain:     ");
1142 	sshbuf_dump(nstate->outgoing_packet, stderr);
1143 #endif
1144 
1145 	if (comp && comp->enabled) {
1146 #if 0
1147 		len = sshbuf_len(state->outgoing_packet);
1148 		/* skip header, compress only payload */
1149 		if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1150 			goto out;
1151 		sshbuf_reset(state->compression_buffer);
1152 		if ((r = compress_buffer(ssh, state->outgoing_packet,
1153 		    state->compression_buffer)) != 0)
1154 			goto out;
1155 		sshbuf_reset(state->outgoing_packet);
1156 		if ((r = sshbuf_put(state->outgoing_packet,
1157 		    "\0\0\0\0\0", 5)) != 0 ||
1158 		    (r = sshbuf_putb(state->outgoing_packet,
1159 		    state->compression_buffer)) != 0)
1160 			goto out;
1161 		DBG(debug("compression: raw %d compressed %zd", len,
1162 		    sshbuf_len(state->outgoing_packet)));
1163 #endif
1164 	}
1165 
1166 	/* sizeof (packet_len + pad_len + payload) */
1167 	len = sshbuf_len(nstate->outgoing_packet);
1168 
1169 	/*
1170 	 * calc size of padding, alloc space, get random data,
1171 	 * minimum padding is 4 bytes
1172 	 */
1173 	len -= aadlen; /* packet length is not encrypted for EtM modes */
1174 	padlen = block_size - (len % block_size);
1175 	if (padlen < 4)
1176 		padlen += block_size;
1177 	if (nstate->extra_pad) {
1178 		/* will wrap if extra_pad+padlen > 255 */
1179 		nstate->extra_pad =
1180 		    roundup(nstate->extra_pad, block_size);
1181 		pad = nstate->extra_pad -
1182 		    ((len + padlen) % nstate->extra_pad);
1183 		DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1184 		    __func__, pad, len, padlen, nstate->extra_pad));
1185 		padlen += pad;
1186 		nstate->extra_pad = 0;
1187 	}
1188 	if ((r = sshbuf_reserve(nstate->outgoing_packet, padlen, &cp)) != 0)
1189 		goto out;
1190 	if (enc && !nstate->send_context.plaintext) {
1191 		/* random padding */
1192 		arc4random_buf(cp, padlen);
1193 	} else {
1194 		/* clear padding */
1195 		explicit_bzero(cp, padlen);
1196 	}
1197 	/* sizeof (packet_len + pad_len + payload + padding) */
1198 	len = sshbuf_len(nstate->outgoing_packet);
1199 	cp = sshbuf_mutable_ptr(nstate->outgoing_packet);
1200 	if (cp == NULL) {
1201 		r = SSH_ERR_INTERNAL_ERROR;
1202 		goto out;
1203 	}
1204 	/* packet_length includes payload, padding and padding length field */
1205 	POKE_U32(cp, len - 4);
1206 	cp[4] = padlen;
1207 	DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1208 	    len, padlen, aadlen));
1209 
1210 	/* compute MAC over seqnr and packet(length fields, payload, padding) */
1211 	if (mac && mac->enabled && !mac->etm) {
1212 		if ((r = mac_compute(mac, nstate->p_send.seqnr,
1213 		    sshbuf_ptr(nstate->outgoing_packet), len,
1214 		    macbuf, sizeof(macbuf))) != 0)
1215 			goto out;
1216 		DBG(debug("done calc MAC out #%d", nstate->p_send.seqnr));
1217 	}
1218 	/* encrypt packet and append to output buffer. */
1219 	if ((r = sshbuf_reserve(nstate->output,
1220 	    sshbuf_len(nstate->outgoing_packet) + authlen, &cp)) != 0)
1221 		goto out;
1222 	if ((r = cipher_crypt(&nstate->send_context, nstate->p_send.seqnr, cp,
1223 	    sshbuf_ptr(nstate->outgoing_packet),
1224 	    len - aadlen, aadlen, authlen)) != 0)
1225 		goto out;
1226 	/* append unencrypted MAC */
1227 	if (mac && mac->enabled) {
1228 		if (mac->etm) {
1229 			/* EtM: compute mac over aadlen + cipher text */
1230 			if ((r = mac_compute(mac, nstate->p_send.seqnr,
1231 			    cp, len, macbuf, sizeof(macbuf))) != 0)
1232 				goto out;
1233 			DBG(debug("done calc MAC(EtM) out #%d",
1234 			    nstate->p_send.seqnr));
1235 		}
1236 		if ((r = sshbuf_put(nstate->output, macbuf, mac->mac_len)) != 0)
1237 			goto out;
1238 	}
1239 #ifdef PACKET_DEBUG
1240 	fprintf(stderr, "encrypted: ");
1241 	sshbuf_dump(nstate->output, stderr);
1242 #endif
1243 	/* increment sequence number for outgoing packets */
1244 	if (++nstate->p_send.seqnr == 0)
1245 		logit("outgoing seqnr wraps around");
1246 	if (++nstate->p_send.packets == 0)
1247 		if (!(nstate->compat & SSH_BUG_NOREKEY))
1248 			return SSH_ERR_NEED_REKEY;
1249 	nstate->p_send.blocks += len / block_size;
1250 	nstate->p_send.bytes += len;
1251 	sshbuf_reset(nstate->outgoing_packet);
1252 
1253 	if (type == SSH2_MSG_NEWKEYS)
1254 		r = ssh_set_newkeys(nstate, MODE_OUT);
1255 	//else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1256 	//	r = ssh_packet_enable_delayed_compress(ssh);
1257 	else
1258 		r = 0;
1259  out:
1260 	return r;
1261 }
1262 
1263 int
ssh_packet_send2(ncrack_ssh_state * nstate)1264 ssh_packet_send2(ncrack_ssh_state *nstate)
1265 {
1266 	//struct session_state *state = ssh->state;
1267 	struct packet *p;
1268 	u_char type;
1269 	int r;
1270 
1271 	type = sshbuf_ptr(nstate->outgoing_packet)[5];
1272 
1273 	/* during rekeying we can only send key exchange messages */
1274 	if (nstate->rekeying) {
1275 
1276 		if ((type < SSH2_MSG_TRANSPORT_MIN) ||
1277 		    (type > SSH2_MSG_TRANSPORT_MAX) ||
1278 		    (type == SSH2_MSG_SERVICE_REQUEST) ||
1279 		    (type == SSH2_MSG_SERVICE_ACCEPT)) {
1280 			debug("enqueue packet: %u", type);
1281 			p = calloc(1, sizeof(*p));
1282 			if (p == NULL)
1283 				return SSH_ERR_ALLOC_FAIL;
1284 			p->type = type;
1285 			p->payload = nstate->outgoing_packet;
1286 
1287 			//TAILQ_INSERT_TAIL(&nstate->outgoing, p, next);
1288 
1289 			nstate->outgoing_packet = sshbuf_new();
1290 			if (nstate->outgoing_packet == NULL)
1291 				return SSH_ERR_ALLOC_FAIL;
1292 			return 0;
1293 		}
1294 	}
1295 
1296 	/* rekeying starts with sending KEXINIT */
1297 	if (type == SSH2_MSG_KEXINIT)
1298 		nstate->rekeying = 1;
1299 
1300 	if ((r = ssh_packet_send2_wrapped(nstate)) != 0)
1301 		return r;
1302 
1303 	/* after a NEWKEYS message we can send the complete queue */
1304 	if (type == SSH2_MSG_NEWKEYS) {
1305 
1306 		nstate->rekeying = 0;
1307 
1308 		//state->rekey_time = monotime();
1309 		//while ((p = TAILQ_FIRST(&state->outgoing))) {
1310 		//	type = p->type;
1311 		//	debug("dequeue packet: %u", type);
1312 		//	sshbuf_free(state->outgoing_packet);
1313 		//	state->outgoing_packet = p->payload;
1314 		//	TAILQ_REMOVE(&state->outgoing, p, next);
1315 		//	free(p);
1316 			//if ((r = ssh_packet_send2_wrapped(nstate)) != 0)
1317 			//	return r;
1318 		//}
1319 	}
1320 	return 0;
1321 }
1322 
1323 /*
1324  * Waits until a packet has been received, and returns its type.  Note that
1325  * no other data is processed until this returns, so this function should not
1326  * be used during the interactive session.
1327  */
1328 
1329 #if 0
1330 int
1331 ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1332 {
1333 	struct session_state *state = ssh->state;
1334 	int len, r, ms_remain, cont;
1335 	fd_set *setp;
1336 	char buf[8192];
1337 	struct timeval timeout, start, *timeoutp = NULL;
1338 
1339 	DBG(debug("packet_read()"));
1340 
1341 	setp = calloc(howmany(state->connection_in + 1,
1342 	    NFDBITS), sizeof(fd_mask));
1343 	if (setp == NULL)
1344 		return SSH_ERR_ALLOC_FAIL;
1345 
1346 	/*
1347 	 * Since we are blocking, ensure that all written packets have
1348 	 * been sent.
1349 	 */
1350 	if ((r = ssh_packet_write_wait(ssh)) != 0)
1351 		goto out;
1352 
1353 	/* Stay in the loop until we have received a complete packet. */
1354 	for (;;) {
1355 		/* Try to read a packet from the buffer. */
1356 		r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1357 		if (r != 0)
1358 			break;
1359 		if (!compat20 && (
1360 		    *typep == SSH_SMSG_SUCCESS
1361 		    || *typep == SSH_SMSG_FAILURE
1362 		    || *typep == SSH_CMSG_EOF
1363 		    || *typep == SSH_CMSG_EXIT_CONFIRMATION))
1364 			if ((r = sshpkt_get_end(ssh)) != 0)
1365 				break;
1366 		/* If we got a packet, return it. */
1367 		if (*typep != SSH_MSG_NONE)
1368 			break;
1369 		/*
1370 		 * Otherwise, wait for some data to arrive, add it to the
1371 		 * buffer, and try again.
1372 		 */
1373 		memset(setp, 0, howmany(state->connection_in + 1,
1374 		    NFDBITS) * sizeof(fd_mask));
1375 		FD_SET(state->connection_in, setp);
1376 
1377 		if (state->packet_timeout_ms > 0) {
1378 			ms_remain = state->packet_timeout_ms;
1379 			timeoutp = &timeout;
1380 		}
1381 		/* Wait for some data to arrive. */
1382 		for (;;) {
1383 			if (state->packet_timeout_ms != -1) {
1384 				ms_to_timeval(&timeout, ms_remain);
1385 				gettimeofday(&start, NULL);
1386 			}
1387 			if ((r = select(state->connection_in + 1, setp,
1388 			    NULL, NULL, timeoutp)) >= 0)
1389 				break;
1390 			if (errno != EAGAIN && errno != EINTR &&
1391 			    errno != EWOULDBLOCK)
1392 				break;
1393 			if (state->packet_timeout_ms == -1)
1394 				continue;
1395 			ms_subtract_diff(&start, &ms_remain);
1396 			if (ms_remain <= 0) {
1397 				r = 0;
1398 				break;
1399 			}
1400 		}
1401 		if (r == 0)
1402 			return SSH_ERR_CONN_TIMEOUT;
1403 		/* Read data from the socket. */
1404 		do {
1405 			cont = 0;
1406 			//len = roaming_read(state->connection_in, buf, sizeof(buf), &cont);
1407 		} while (len == 0 && cont);
1408 		if (len == 0) {
1409 			r = SSH_ERR_CONN_CLOSED;
1410 			goto out;
1411 		}
1412 		if (len < 0) {
1413 			r = SSH_ERR_SYSTEM_ERROR;
1414 			goto out;
1415 		}
1416 
1417 		/* Append it to the buffer. */
1418 		if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1419 			goto out;
1420 	}
1421  out:
1422 	free(setp);
1423 	return r;
1424 }
1425 
1426 int
1427 ssh_packet_read(struct ssh *ssh)
1428 {
1429 	u_char type;
1430 	int r;
1431 
1432 	if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1433 		fatal("%s: %s", __func__, ssh_err(r));
1434 	return type;
1435 }
1436 #endif
1437 
1438 int
ncrackssh_ssh_packet_read(ncrack_ssh_state * nstate)1439 ncrackssh_ssh_packet_read(ncrack_ssh_state *nstate)
1440 {
1441 	u_char type;
1442 	int r;
1443 	if ((r = ssh_packet_read_poll_seqnr(nstate, &type, NULL)) != 0)
1444     ;
1445     //printf("ssh_packet_read_poll_seqnr returned err: %d\n", r);
1446 		//fatal("%s: %s", __func__, ssh_err(r));
1447 
1448   //ssh_packet_read_poll_seqnr(nstate, &type, NULL);
1449 
1450 	return type;
1451 }
1452 
1453 
1454 
1455 #if 0
1456 /*
1457  * Waits until a packet has been received, verifies that its type matches
1458  * that given, and gives a fatal error and exits if there is a mismatch.
1459  */
1460 
1461 int
1462 ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1463 {
1464 	int r;
1465 	u_char type;
1466 
1467 	if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1468 		return r;
1469 	if (type != expected_type) {
1470 		if ((r = sshpkt_disconnect(ssh,
1471 		    "Protocol error: expected packet type %d, got %d",
1472 		    expected_type, type)) != 0)
1473 			return r;
1474 		return SSH_ERR_PROTOCOL_ERROR;
1475 	}
1476 	return 0;
1477 }
1478 #endif
1479 
1480 /* Checks if a full packet is available in the data received so far via
1481  * packet_process_incoming.  If so, reads the packet; otherwise returns
1482  * SSH_MSG_NONE.  This does not wait for data from the connection.
1483  *
1484  * SSH_MSG_DISCONNECT is handled specially here.  Also,
1485  * SSH_MSG_IGNORE messages are skipped by this function and are never returned
1486  * to higher levels.
1487  */
1488 
1489 int
ssh_packet_read_poll1(ncrack_ssh_state * nstate,u_char * typep)1490 ssh_packet_read_poll1(ncrack_ssh_state *nstate, u_char *typep)
1491 {
1492 	//struct session_state *state = ssh->state;
1493 	u_int len, padded_len;
1494 	//const char *emsg;
1495 	const u_char *cp;
1496 	u_char *p;
1497 	u_int checksum, stored_checksum;
1498 	int r;
1499 
1500 	*typep = SSH_MSG_NONE;
1501 
1502 	/* Check if input size is less than minimum packet size. */
1503 	if (sshbuf_len(nstate->input) < 4 + 8)
1504 		return 0;
1505 	/* Get length of incoming packet. */
1506 	len = PEEK_U32(sshbuf_ptr(nstate->input));
1507 	if (len < 1 + 2 + 2 || len > 256 * 1024) {
1508 		if ((r = sshpkt_disconnect(nstate, "Bad packet length %u",
1509 		    len)) != 0)
1510 			return r;
1511 		return SSH_ERR_CONN_CORRUPT;
1512 	}
1513 	padded_len = (len + 8) & ~7;
1514 
1515 	/* Check if the packet has been entirely received. */
1516 	if (sshbuf_len(nstate->input) < 4 + padded_len)
1517 		return 0;
1518 
1519 	/* The entire packet is in buffer. */
1520 
1521 	/* Consume packet length. */
1522 	if ((r = sshbuf_consume(nstate->input, 4)) != 0)
1523 		goto out;
1524 
1525 
1526 #if 0
1527 	/*
1528 	 * Cryptographic attack detector for ssh
1529 	 * (C)1998 CORE-SDI, Buenos Aires Argentina
1530 	 * Ariel Futoransky(futo@core-sdi.com)
1531 	 */
1532 	if (!nstate->receive_context.plaintext) {
1533 		emsg = NULL;
1534 		switch (detect_attack(&nstate->deattack,
1535 		    sshbuf_ptr(nstate->input), padded_len)) {
1536 		case DEATTACK_OK:
1537 			break;
1538 		case DEATTACK_DETECTED:
1539 			emsg = "crc32 compensation attack detected";
1540 			break;
1541 		case DEATTACK_DOS_DETECTED:
1542 			emsg = "deattack denial of service detected";
1543 			break;
1544 		default:
1545 			emsg = "deattack error";
1546 			break;
1547 		}
1548 		if (emsg != NULL) {
1549 			ssh_error("%s", emsg);
1550 			if ((r = sshpkt_disconnect(nstate, "%s", emsg)) != 0 ||
1551 			    (r = ssh_packet_write_wait(nstate)) != 0)
1552 					return r;
1553 			return SSH_ERR_CONN_CORRUPT;
1554 		}
1555 	}
1556 #endif
1557 
1558 	/* Decrypt data to incoming_packet. */
1559 	sshbuf_reset(nstate->incoming_packet);
1560 	if ((r = sshbuf_reserve(nstate->incoming_packet, padded_len, &p)) != 0)
1561 		goto out;
1562 	if ((r = cipher_crypt(&nstate->receive_context, 0, p,
1563 	    sshbuf_ptr(nstate->input), padded_len, 0, 0)) != 0)
1564 		goto out;
1565 
1566 	if ((r = sshbuf_consume(nstate->input, padded_len)) != 0)
1567 		goto out;
1568 
1569 #ifdef PACKET_DEBUG
1570 	fprintf(stderr, "read_poll plain: ");
1571 	sshbuf_dump(nstate->incoming_packet, stderr);
1572 #endif
1573 
1574 	/* Compute packet checksum. */
1575 	checksum = ssh_crc32(sshbuf_ptr(nstate->incoming_packet),
1576 	    sshbuf_len(nstate->incoming_packet) - 4);
1577 
1578 	/* Skip padding. */
1579 	if ((r = sshbuf_consume(nstate->incoming_packet, 8 - len % 8)) != 0)
1580 		goto out;
1581 
1582 	/* Test check bytes. */
1583 	if (len != sshbuf_len(nstate->incoming_packet)) {
1584 		ssh_error("%s: len %d != sshbuf_len %zd", __func__,
1585 		    len, sshbuf_len(nstate->incoming_packet));
1586 		if ((r = sshpkt_disconnect(nstate, "invalid packet length")) != 0 ||
1587 		    (r = ssh_packet_write_wait(nstate)) != 0)
1588 			return r;
1589 		return SSH_ERR_CONN_CORRUPT;
1590 	}
1591 
1592 	cp = sshbuf_ptr(nstate->incoming_packet) + len - 4;
1593 	stored_checksum = PEEK_U32(cp);
1594 	if (checksum != stored_checksum) {
1595 		ssh_error("Corrupted check bytes on input");
1596 		if ((r = sshpkt_disconnect(nstate, "connection corrupted")) != 0 ||
1597 		    (r = ssh_packet_write_wait(nstate)) != 0)
1598 			return r;
1599 		return SSH_ERR_CONN_CORRUPT;
1600 	}
1601 	if ((r = sshbuf_consume_end(nstate->incoming_packet, 4)) < 0)
1602 		goto out;
1603 
1604 #if 0
1605 	if (nstate->packet_compression) {
1606 		sshbuf_reset(nstate->compression_buffer);
1607 		if ((r = uncompress_buffer(ssh, nstate->incoming_packet,
1608 		    nstate->compression_buffer)) != 0)
1609 			goto out;
1610 		sshbuf_reset(nstate->incoming_packet);
1611 		if ((r = sshbuf_putb(nstate->incoming_packet,
1612 		    nstate->compression_buffer)) != 0)
1613 			goto out;
1614 	}
1615 #endif
1616 	nstate->p_read.packets++;
1617 	nstate->p_read.bytes += padded_len + 4;
1618 	if ((r = sshbuf_get_u8(nstate->incoming_packet, typep)) != 0)
1619 		goto out;
1620 	if (*typep < SSH_MSG_MIN || *typep > SSH_MSG_MAX) {
1621 		ssh_error("Invalid ssh1 packet type: %d", *typep);
1622 		if ((r = sshpkt_disconnect(nstate, "invalid packet type")) != 0 ||
1623 		    (r = ssh_packet_write_wait(nstate)) != 0)
1624 			return r;
1625 		return SSH_ERR_PROTOCOL_ERROR;
1626 	}
1627 	r = 0;
1628  out:
1629 	return r;
1630 }
1631 
1632 int
ssh_packet_read_poll2(ncrack_ssh_state * nstate,u_char * typep,u_int32_t * seqnr_p)1633 ssh_packet_read_poll2(ncrack_ssh_state *nstate, u_char *typep, u_int32_t *seqnr_p)
1634 {
1635 	//struct session_state *state = ssh->state;
1636 	u_int padlen, need;
1637 	u_char *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1638 	u_int maclen, aadlen = 0, authlen = 0, block_size;
1639 	struct sshenc *enc   = NULL;
1640 	struct sshmac *mac   = NULL;
1641 	//struct sshcomp *comp = NULL;
1642 	int r;
1643 
1644 	*typep = SSH_MSG_NONE;
1645 
1646 	if (nstate->packet_discard)
1647 	  return 0;
1648 
1649 	if (nstate->newkeys[MODE_IN] != NULL) {
1650 		enc  = &nstate->newkeys[MODE_IN]->enc;
1651 		mac  = &nstate->newkeys[MODE_IN]->mac;
1652 		//comp = &nstate->newkeys[MODE_IN]->comp;
1653 		/* disable mac for authenticated encryption */
1654 		if ((authlen = cipher_authlen(enc->cipher)) != 0)
1655 			mac = NULL;
1656 	}
1657 
1658 	maclen = mac && mac->enabled ? mac->mac_len : 0;
1659 	block_size = enc ? enc->block_size : 8;
1660 	aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1661 
1662 	if (aadlen && nstate->packlen == 0) {
1663 		if (cipher_get_length(&nstate->receive_context,
1664 		    &nstate->packlen, nstate->p_read.seqnr,
1665 		    sshbuf_ptr(nstate->input), sshbuf_len(nstate->input)) != 0)
1666 			return 0;
1667 		if (nstate->packlen < 1 + 4 ||
1668 		    nstate->packlen > PACKET_MAX_SIZE) {
1669 #ifdef PACKET_DEBUG
1670 			sshbuf_dump(nstate->input, stderr);
1671 #endif
1672 			logit("Bad packet length %u.", nstate->packlen);
1673 			if ((r = sshpkt_disconnect(nstate, "Packet corrupt")) != 0)
1674 				return r;
1675 		}
1676 		sshbuf_reset(nstate->incoming_packet);
1677 	} else if (nstate->packlen == 0) {
1678 		/*
1679 		 * check if input size is less than the cipher block size,
1680 		 * decrypt first block and extract length of incoming packet
1681 		 */
1682 		if (sshbuf_len(nstate->input) < block_size)
1683 			return 0;
1684 		sshbuf_reset(nstate->incoming_packet);
1685 		if ((r = sshbuf_reserve(nstate->incoming_packet, block_size,
1686 		    &cp)) != 0)
1687 			goto out;
1688 		if ((r = cipher_crypt(&nstate->receive_context,
1689 		    nstate->p_send.seqnr, cp, sshbuf_ptr(nstate->input),
1690 		    block_size, 0, 0)) != 0)
1691 			goto out;
1692 		nstate->packlen = PEEK_U32(sshbuf_ptr(nstate->incoming_packet));
1693 		if (nstate->packlen < 1 + 4 ||
1694 		    nstate->packlen > PACKET_MAX_SIZE) {
1695 #ifdef PACKET_DEBUG
1696 			fprintf(stderr, "input: \n");
1697 			sshbuf_dump(nstate->input, stderr);
1698 			fprintf(stderr, "incoming_packet: \n");
1699 			sshbuf_dump(nstate->incoming_packet, stderr);
1700 #endif
1701 			logit("Bad packet length %u.", nstate->packlen);
1702 			return ssh_packet_start_discard(nstate, enc, mac,
1703 			    nstate->packlen, PACKET_MAX_SIZE);
1704 		}
1705 		if ((r = sshbuf_consume(nstate->input, block_size)) != 0)
1706 			goto out;
1707 	}
1708 	DBG(debug("input: packet len %u", nstate->packlen+4));
1709 
1710 	if (aadlen) {
1711 		/* only the payload is encrypted */
1712 		need = nstate->packlen;
1713 	} else {
1714 		/*
1715 		 * the payload size and the payload are encrypted, but we
1716 		 * have a partial packet of block_size bytes
1717 		 */
1718 		need = 4 + nstate->packlen - block_size;
1719 	}
1720 	DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1721 	    " aadlen %d", block_size, need, maclen, authlen, aadlen));
1722 	if (need % block_size != 0) {
1723 		logit("padding error: need %d block %d mod %d",
1724 		    need, block_size, need % block_size);
1725 		return ssh_packet_start_discard(nstate, enc, mac,
1726 		    nstate->packlen, PACKET_MAX_SIZE - block_size);
1727 	}
1728 	/*
1729 	 * check if the entire packet has been received and
1730 	 * decrypt into incoming_packet:
1731 	 * 'aadlen' bytes are unencrypted, but authenticated.
1732 	 * 'need' bytes are encrypted, followed by either
1733 	 * 'authlen' bytes of authentication tag or
1734 	 * 'maclen' bytes of message authentication code.
1735 	 */
1736 	if (sshbuf_len(nstate->input) < aadlen + need + authlen + maclen)
1737 		return 0;
1738 #ifdef PACKET_DEBUG
1739 	fprintf(stderr, "read_poll enc/full: ");
1740 	sshbuf_dump(nstate->input, stderr);
1741 #endif
1742 	/* EtM: compute mac over encrypted input */
1743 	if (mac && mac->enabled && mac->etm) {
1744 		if ((r = mac_compute(mac, nstate->p_read.seqnr,
1745 		    sshbuf_ptr(nstate->input), aadlen + need,
1746 		    macbuf, sizeof(macbuf))) != 0)
1747 			goto out;
1748 	}
1749 	if ((r = sshbuf_reserve(nstate->incoming_packet, aadlen + need,
1750 	    &cp)) != 0)
1751 		goto out;
1752 	if ((r = cipher_crypt(&nstate->receive_context, nstate->p_read.seqnr, cp,
1753 	    sshbuf_ptr(nstate->input), need, aadlen, authlen)) != 0)
1754 		goto out;
1755 	if ((r = sshbuf_consume(nstate->input, aadlen + need + authlen)) != 0)
1756 		goto out;
1757 	/*
1758 	 * compute MAC over seqnr and packet,
1759 	 * increment sequence number for incoming packet
1760 	 */
1761 	if (mac && mac->enabled) {
1762 		if (!mac->etm)
1763 			if ((r = mac_compute(mac, nstate->p_read.seqnr,
1764 			    sshbuf_ptr(nstate->incoming_packet),
1765 			    sshbuf_len(nstate->incoming_packet),
1766 			    macbuf, sizeof(macbuf))) != 0)
1767 				goto out;
1768 		if (timingsafe_bcmp(macbuf, sshbuf_ptr(nstate->input),
1769 		    mac->mac_len) != 0) {
1770 			logit("Corrupted MAC on input.");
1771 			if (need > PACKET_MAX_SIZE)
1772 				return SSH_ERR_INTERNAL_ERROR;
1773 			return ssh_packet_start_discard(nstate, enc, mac,
1774 			    nstate->packlen, PACKET_MAX_SIZE - need);
1775 		}
1776 
1777 		DBG(debug("MAC #%d ok", nstate->p_read.seqnr));
1778 		if ((r = sshbuf_consume(nstate->input, mac->mac_len)) != 0)
1779 			goto out;
1780 	}
1781 	if (seqnr_p != NULL)
1782 		*seqnr_p = nstate->p_read.seqnr;
1783 	if (++nstate->p_read.seqnr == 0)
1784 		logit("incoming seqnr wraps around");
1785 	if (++nstate->p_read.packets == 0)
1786 		if (!(nstate->compat & SSH_BUG_NOREKEY))
1787 			return SSH_ERR_NEED_REKEY;
1788 	nstate->p_read.blocks += (nstate->packlen + 4) / block_size;
1789 	nstate->p_read.bytes += nstate->packlen + 4;
1790 
1791 	/* get padlen */
1792 	padlen = sshbuf_ptr(nstate->incoming_packet)[4];
1793 	DBG(debug("input: padlen %d", padlen));
1794 	if (padlen < 4)	{
1795 		if ((r = sshpkt_disconnect(nstate,
1796 		    "Corrupted padlen %d on input.", padlen)) != 0 ||
1797 		    (r = ssh_packet_write_wait(nstate)) != 0)
1798 			return r;
1799 		return SSH_ERR_CONN_CORRUPT;
1800 	}
1801 
1802 	/* skip packet size + padlen, discard padding */
1803 	if ((r = sshbuf_consume(nstate->incoming_packet, 4 + 1)) != 0 ||
1804 	    ((r = sshbuf_consume_end(nstate->incoming_packet, padlen)) != 0))
1805 		goto out;
1806 
1807 	DBG(debug("input: len before de-compress %zd",
1808 	    sshbuf_len(nstate->incoming_packet)));
1809 
1810 #if 0
1811 	if (comp && comp->enabled) {
1812 		sshbuf_reset(nstate->compression_buffer);
1813 		if ((r = uncompress_buffer(ssh, nstate->incoming_packet,
1814 		    nstate->compression_buffer)) != 0)
1815 			goto out;
1816 		sshbuf_reset(nstate->incoming_packet);
1817 		if ((r = sshbuf_putb(nstate->incoming_packet,
1818 		    nstate->compression_buffer)) != 0)
1819 			goto out;
1820 		DBG(debug("input: len after de-compress %zd",
1821 		    sshbuf_len(nstate->incoming_packet)));
1822 	}
1823 #endif
1824 	/*
1825 	 * get packet type, implies consume.
1826 	 * return length of payload (without type field)
1827 	 */
1828 	if ((r = sshbuf_get_u8(nstate->incoming_packet, typep)) != 0)
1829 		goto out;
1830 	if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1831 		if ((r = sshpkt_disconnect(nstate,
1832 		    "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1833 		    (r = ssh_packet_write_wait(nstate)) != 0)
1834 			return r;
1835 		return SSH_ERR_PROTOCOL_ERROR;
1836 	}
1837 	if (*typep == SSH2_MSG_NEWKEYS) {
1838 		r = ssh_set_newkeys(nstate, MODE_IN);
1839   }
1840 #if 0
1841 	else if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !nstate->server_side)
1842 		r = ssh_packet_enable_delayed_compress(ssh);
1843 #endif
1844 	else
1845 		r = 0;
1846 #ifdef PACKET_DEBUG
1847 	fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1848 	sshbuf_dump(nstate->incoming_packet, stderr);
1849 #endif
1850 	/* reset for next packet */
1851 	nstate->packlen = 0;
1852  out:
1853 	return r;
1854 }
1855 
1856 int
ssh_packet_read_poll_seqnr(ncrack_ssh_state * nstate,u_char * typep,u_int32_t * seqnr_p)1857 ssh_packet_read_poll_seqnr(ncrack_ssh_state *nstate, u_char *typep, u_int32_t *seqnr_p)
1858 {
1859 //	struct session_state *state = ssh->state;
1860 	u_int reason, seqnr;
1861 	int r;
1862 	u_char *msg;
1863 
1864 	for (;;) {
1865 		msg = NULL;
1866 		if (nstate->compat20) {
1867 			r = ssh_packet_read_poll2(nstate, typep, seqnr_p);
1868 			if (r != 0)
1869 				return r;
1870 			if (*typep) {
1871 				nstate->keep_alive_timeouts = 0;
1872 				DBG(debug("received packet type %d", *typep));
1873 			}
1874 			switch (*typep) {
1875 			case SSH2_MSG_IGNORE:
1876 				debug3("Received SSH2_MSG_IGNORE");
1877 				break;
1878 			case SSH2_MSG_DEBUG:
1879 				if ((r = sshpkt_get_u8(nstate, NULL)) != 0 ||
1880 				    (r = sshpkt_get_string(nstate, &msg, NULL)) != 0 ||
1881 				    (r = sshpkt_get_string(nstate, NULL, NULL)) != 0) {
1882 					if (msg)
1883 						free(msg);
1884 					return r;
1885 				}
1886 				debug("Remote: %.900s", msg);
1887 				free(msg);
1888 				break;
1889 			case SSH2_MSG_DISCONNECT:
1890 				if ((r = sshpkt_get_u32(nstate, &reason)) != 0 ||
1891 				    (r = sshpkt_get_string(nstate, &msg, NULL)) != 0)
1892 					return r;
1893 				/* Ignore normal client exit notifications */
1894 #if 0
1895 				do_log2(ssh->state->server_side &&
1896 				    reason == SSH2_DISCONNECT_BY_APPLICATION ?
1897 				    SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1898 				    "Received disconnect from %s: %u: %.400s",
1899 				    ssh_remote_ipaddr(ssh), reason, msg);
1900 #endif
1901 				free(msg);
1902 				return SSH_ERR_DISCONNECTED;
1903 			case SSH2_MSG_UNIMPLEMENTED:
1904 				if ((r = sshpkt_get_u32(nstate, &seqnr)) != 0)
1905 					return r;
1906 				debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1907 				    seqnr);
1908 				break;
1909 			default:
1910 				return 0;
1911 			}
1912 		}
1913     else {
1914 			r = ssh_packet_read_poll1(nstate, typep);
1915 			switch (*typep) {
1916 			case SSH_MSG_NONE:
1917 				return SSH_MSG_NONE;
1918 			case SSH_MSG_IGNORE:
1919 				break;
1920 			case SSH_MSG_DEBUG:
1921 				if ((r = sshpkt_get_string(nstate, &msg, NULL)) != 0)
1922 					return r;
1923 				debug("Remote: %.900s", msg);
1924 				free(msg);
1925 				break;
1926 			case SSH_MSG_DISCONNECT:
1927 				if ((r = sshpkt_get_string(nstate, &msg, NULL)) != 0)
1928 					return r;
1929 				//ssh_error("Received disconnect from %s: %.400s",
1930 				//    ssh_remote_ipaddr(ssh), msg);
1931 				free(msg);
1932 				return SSH_ERR_DISCONNECTED;
1933 			default:
1934 				DBG(debug("received packet type %d", *typep));
1935 				return 0;
1936 			}
1937 		}
1938 	}
1939 }
1940 
1941 /*
1942  * Buffers the given amount of input characters.  This is intended to be used
1943  * together with packet_read_poll.
1944  */
1945 
1946 int
ssh_packet_process_incoming(ncrack_ssh_state * nstate,const char * buf,u_int len)1947 ssh_packet_process_incoming(ncrack_ssh_state *nstate, const char *buf, u_int len)
1948 {
1949 	//struct session_state *state = ssh->state;
1950 	int r;
1951 
1952 	if (nstate->packet_discard) {
1953 		nstate->keep_alive_timeouts = 0; /* ?? */
1954 		if (len >= nstate->packet_discard) {
1955 			if ((r = ssh_packet_stop_discard(nstate)) != 0)
1956 				return r;
1957 		}
1958 		nstate->packet_discard -= len;
1959 		return 0;
1960 	}
1961 	if ((r = sshbuf_put(nstate->input, buf, len)) != 0)
1962 		return r;
1963 
1964 	return 0;
1965 }
1966 
1967 int
ssh_packet_remaining(ncrack_ssh_state * nstate)1968 ssh_packet_remaining(ncrack_ssh_state *nstate)
1969 {
1970 	return sshbuf_len(nstate->incoming_packet);
1971 }
1972 
1973 
1974 #if 0
1975 /*
1976  * Sends a diagnostic message from the server to the client.  This message
1977  * can be sent at any time (but not while constructing another message). The
1978  * message is printed immediately, but only if the client is being executed
1979  * in verbose mode.  These messages are primarily intended to ease debugging
1980  * authentication problems.   The length of the formatted message must not
1981  * exceed 1024 bytes.  This will automatically call ssh_packet_write_wait.
1982  */
1983 void
1984 ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1985 {
1986 	char buf[1024];
1987 	va_list args;
1988 	int r;
1989 
1990 	if (compat20 && (ssh->compat & SSH_BUG_DEBUG))
1991 		return;
1992 
1993 	va_start(args, fmt);
1994 	vsnprintf(buf, sizeof(buf), fmt, args);
1995 	va_end(args);
1996 
1997 	if (compat20) {
1998 		if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1999 		    (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
2000 		    (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2001 		    (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2002 		    (r = sshpkt_send(ssh)) != 0)
2003 			fatal("%s: %s", __func__, ssh_err(r));
2004 	} else {
2005 		if ((r = sshpkt_start(ssh, SSH_MSG_DEBUG)) != 0 ||
2006 		    (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2007 		    (r = sshpkt_send(ssh)) != 0)
2008 			fatal("%s: %s", __func__, ssh_err(r));
2009 	}
2010 	if ((r = ssh_packet_write_wait(ssh)) != 0)
2011 		fatal("%s: %s", __func__, ssh_err(r));
2012 }
2013 #endif
2014 
2015 /*
2016  * Pretty-print connection-terminating errors and exit.
2017  */
2018 void
sshpkt_fatal(struct ssh * ssh,const char * tag,int r)2019 sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
2020 {
2021 	switch (r) {
2022 	case SSH_ERR_CONN_CLOSED:
2023 		logit("Connection closed by %.200s", ssh_remote_ipaddr(ssh));
2024 		cleanup_exit(255);
2025 	case SSH_ERR_CONN_TIMEOUT:
2026 		logit("Connection to %.200s timed out", ssh_remote_ipaddr(ssh));
2027 		cleanup_exit(255);
2028 	case SSH_ERR_DISCONNECTED:
2029 		logit("Disconnected from %.200s",
2030 		    ssh_remote_ipaddr(ssh));
2031 		cleanup_exit(255);
2032 	case SSH_ERR_SYSTEM_ERROR:
2033 		if (errno == ECONNRESET) {
2034 			logit("Connection reset by %.200s",
2035 			    ssh_remote_ipaddr(ssh));
2036 			cleanup_exit(255);
2037 		}
2038 		/* FALLTHROUGH */
2039 	case SSH_ERR_NO_CIPHER_ALG_MATCH:
2040 	case SSH_ERR_NO_MAC_ALG_MATCH:
2041 	case SSH_ERR_NO_COMPRESS_ALG_MATCH:
2042 	case SSH_ERR_NO_KEX_ALG_MATCH:
2043 	case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
2044 		if (ssh && ssh->kex && ssh->kex->failed_choice) {
2045 			fatal("Unable to negotiate with %.200s: %s. "
2046 			    "Their offer: %s", ssh_remote_ipaddr(ssh),
2047 			    ssh_err(r), ssh->kex->failed_choice);
2048 		}
2049 		/* FALLTHROUGH */
2050 	default:
2051 		fatal("%s%sConnection to %.200s: %s",
2052 		    tag != NULL ? tag : "", tag != NULL ? ": " : "",
2053 		    ssh_remote_ipaddr(ssh), ssh_err(r));
2054 	}
2055 }
2056 
2057 #if 0
2058 /*
2059  * Logs the error plus constructs and sends a disconnect packet, closes the
2060  * connection, and exits.  This function never returns. The error message
2061  * should not contain a newline.  The length of the formatted message must
2062  * not exceed 1024 bytes.
2063  */
2064 void
2065 ssh_packet_disconnect(ssh *ssh, const char *fmt,...)
2066 {
2067 	char buf[1024];
2068 	va_list args;
2069 	static int disconnecting = 0;
2070 	int r;
2071 
2072 	if (disconnecting)	/* Guard against recursive invocations. */
2073 		fatal("packet_disconnect called recursively.");
2074 	disconnecting = 1;
2075 
2076 	/*
2077 	 * Format the message.  Note that the caller must make sure the
2078 	 * message is of limited size.
2079 	 */
2080 	va_start(args, fmt);
2081 	vsnprintf(buf, sizeof(buf), fmt, args);
2082 	va_end(args);
2083 
2084 	/* Display the error locally */
2085 	logit("Disconnecting: %.100s", buf);
2086 
2087 	/*
2088 	 * Send the disconnect message to the other side, and wait
2089 	 * for it to get sent.
2090 	 */
2091 	if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
2092 		sshpkt_fatal(ssh, __func__, r);
2093 
2094 	if ((r = ssh_packet_write_wait(ssh)) != 0)
2095 		sshpkt_fatal(ssh, __func__, r);
2096 
2097 	/* Close the connection. */
2098 	ssh_packet_close(ssh);
2099 	cleanup_exit(255);
2100 }
2101 #endif
2102 
2103 /*
2104  * Checks if there is any buffered output, and tries to write some of
2105  * the output.
2106  */
2107 int
ssh_packet_write_poll(ncrack_ssh_state * nstate)2108 ssh_packet_write_poll(ncrack_ssh_state *nstate)
2109 {
2110 	//struct session_state *state = ssh->state;
2111 	int len = sshbuf_len(nstate->output);
2112 	int cont, r;
2113 
2114 	if (len > 0) {
2115 		cont = 0;
2116 		//len = roaming_write(state->connection_out, sshbuf_ptr(state->output), len, &cont);
2117 		if (len == -1) {
2118 			if (errno == EINTR || errno == EAGAIN ||
2119 			    errno == EWOULDBLOCK)
2120 				return 0;
2121 			return SSH_ERR_SYSTEM_ERROR;
2122 		}
2123 		if (len == 0 && !cont)
2124 			return SSH_ERR_CONN_CLOSED;
2125 		if ((r = sshbuf_consume(nstate->output, len)) != 0)
2126 			return r;
2127 	}
2128 	return 0;
2129 }
2130 
2131 /*
2132  * Calls packet_write_poll repeatedly until all pending output data has been
2133  * written.
2134  */
2135 int
ssh_packet_write_wait(ncrack_ssh_state * nstate)2136 ssh_packet_write_wait(ncrack_ssh_state *nstate)
2137 {
2138 	//fd_set *setp;
2139 	//int ret, r, ms_remain = 0;
2140 	//struct timeval start, timeout, *timeoutp = NULL;
2141 	//struct session_state *state = ssh->state;
2142 
2143 	//setp = calloc(howmany(state->connection_out + 1,
2144 	//    NFDBITS), sizeof(fd_mask));
2145 	//if (setp == NULL)
2146 	//	return SSH_ERR_ALLOC_FAIL;
2147 	ssh_packet_write_poll(nstate);
2148 
2149 #if 0
2150 	while (ssh_packet_have_data_to_write(nstate)) {
2151 		memset(setp, 0, howmany(nstate->connection_out + 1,
2152 		    NFDBITS) * sizeof(fd_mask));
2153 		FD_SET(nstate->connection_out, setp);
2154 
2155 		if (nstate->packet_timeout_ms > 0) {
2156 			ms_remain = nstate->packet_timeout_ms;
2157 			timeoutp = &timeout;
2158 		}
2159 		for (;;) {
2160 			if (nstate->packet_timeout_ms != -1) {
2161 				ms_to_timeval(&timeout, ms_remain);
2162 				gettimeofday(&start, NULL);
2163 			}
2164 			if ((ret = select(state->connection_out + 1,
2165 			    NULL, setp, NULL, timeoutp)) >= 0)
2166 				break;
2167 			if (errno != EAGAIN && errno != EINTR &&
2168 			    errno != EWOULDBLOCK)
2169 				break;
2170 			if (state->packet_timeout_ms == -1)
2171 				continue;
2172 			ms_subtract_diff(&start, &ms_remain);
2173 			if (ms_remain <= 0) {
2174 				ret = 0;
2175 				break;
2176 			}
2177 		}
2178 		if (ret == 0) {
2179 			free(setp);
2180 			return SSH_ERR_CONN_TIMEOUT;
2181 		}
2182 		if ((r = ssh_packet_write_poll(nstate)) != 0) {
2183 			free(setp);
2184 			return r;
2185 		}
2186 	}
2187 	free(setp);
2188 #endif
2189 	return 0;
2190 }
2191 
2192 /* Returns true if there is buffered data to write to the connection. */
2193 
2194 int
ssh_packet_have_data_to_write(struct ssh * ssh)2195 ssh_packet_have_data_to_write(struct ssh *ssh)
2196 {
2197 	return sshbuf_len(ssh->state->output) != 0;
2198 }
2199 
2200 /* Returns true if there is not too much data to write to the connection. */
2201 
2202 int
ssh_packet_not_very_much_data_to_write(struct ssh * ssh)2203 ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
2204 {
2205 	if (ssh->state->interactive_mode)
2206 		return sshbuf_len(ssh->state->output) < 16384;
2207 	else
2208 		return sshbuf_len(ssh->state->output) < 128 * 1024;
2209 }
2210 
2211 void
ssh_packet_set_tos(struct ssh * ssh,int tos)2212 ssh_packet_set_tos(struct ssh *ssh, int tos)
2213 {
2214 #ifndef IP_TOS_IS_BROKEN
2215 	if (!ssh_packet_connection_is_on_socket(ssh))
2216 		return;
2217 	switch (ssh_packet_connection_af(ssh)) {
2218 # ifdef IP_TOS
2219 	case AF_INET:
2220 		debug3("%s: set IP_TOS 0x%02x", __func__, tos);
2221 		if (setsockopt(ssh->state->connection_in,
2222 		    IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2223 			ssh_error("setsockopt IP_TOS %d: %.100s:",
2224 			    tos, strerror(errno));
2225 		break;
2226 # endif /* IP_TOS */
2227 # ifdef IPV6_TCLASS
2228 	case AF_INET6:
2229 		debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
2230 		if (setsockopt(ssh->state->connection_in,
2231 		    IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2232 			ssh_error("setsockopt IPV6_TCLASS %d: %.100s:",
2233 			    tos, strerror(errno));
2234 		break;
2235 # endif /* IPV6_TCLASS */
2236 	}
2237 #endif /* IP_TOS_IS_BROKEN */
2238 }
2239 
2240 /* Informs that the current session is interactive.  Sets IP flags for that. */
2241 
2242 void
ssh_packet_set_interactive(struct ssh * ssh,int interactive,int qos_interactive,int qos_bulk)2243 ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
2244 {
2245 	struct session_state *state = ssh->state;
2246 
2247 	if (state->set_interactive_called)
2248 		return;
2249 	state->set_interactive_called = 1;
2250 
2251 	/* Record that we are in interactive mode. */
2252 	state->interactive_mode = interactive;
2253 
2254 	/* Only set socket options if using a socket.  */
2255 	if (!ssh_packet_connection_is_on_socket(ssh))
2256 		return;
2257 	set_nodelay(state->connection_in);
2258 	ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2259 	    qos_bulk);
2260 }
2261 
2262 /* Returns true if the current connection is interactive. */
2263 
2264 int
ssh_packet_is_interactive(struct ssh * ssh)2265 ssh_packet_is_interactive(struct ssh *ssh)
2266 {
2267 	return ssh->state->interactive_mode;
2268 }
2269 
2270 int
ssh_packet_set_maxsize(struct ssh * ssh,u_int s)2271 ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
2272 {
2273 	struct session_state *state = ssh->state;
2274 
2275 	if (state->set_maxsize_called) {
2276 		logit("packet_set_maxsize: called twice: old %d new %d",
2277 		    state->max_packet_size, s);
2278 		return -1;
2279 	}
2280 	if (s < 4 * 1024 || s > 1024 * 1024) {
2281 		logit("packet_set_maxsize: bad size %d", s);
2282 		return -1;
2283 	}
2284 	state->set_maxsize_called = 1;
2285 	debug("packet_set_maxsize: setting to %d", s);
2286 	state->max_packet_size = s;
2287 	return s;
2288 }
2289 
2290 int
ssh_packet_inc_alive_timeouts(struct ssh * ssh)2291 ssh_packet_inc_alive_timeouts(struct ssh *ssh)
2292 {
2293 	return ++ssh->state->keep_alive_timeouts;
2294 }
2295 
2296 void
ssh_packet_set_alive_timeouts(struct ssh * ssh,int ka)2297 ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
2298 {
2299 	ssh->state->keep_alive_timeouts = ka;
2300 }
2301 
2302 u_int
ssh_packet_get_maxsize(struct ssh * ssh)2303 ssh_packet_get_maxsize(struct ssh *ssh)
2304 {
2305 	return ssh->state->max_packet_size;
2306 }
2307 
2308 #if 0
2309 /*
2310  * 9.2.  Ignored Data Message
2311  *
2312  *   byte      SSH_MSG_IGNORE
2313  *   string    data
2314  *
2315  * All implementations MUST understand (and ignore) this message at any
2316  * time (after receiving the protocol version). No implementation is
2317  * required to send them. This message can be used as an additional
2318  * protection measure against advanced traffic analysis techniques.
2319  */
2320 void
2321 ssh_packet_send_ignore(struct ssh *ssh, int nbytes)
2322 {
2323 	u_int32_t rnd = 0;
2324 	int r, i;
2325 
2326 	if ((r = sshpkt_start(ssh, compat20 ?
2327 	    SSH2_MSG_IGNORE : SSH_MSG_IGNORE)) != 0 ||
2328 	    (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2329 		fatal("%s: %s", __func__, ssh_err(r));
2330 	for (i = 0; i < nbytes; i++) {
2331 		if (i % 4 == 0)
2332 			rnd = arc4random();
2333 		if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2334 			fatal("%s: %s", __func__, ssh_err(r));
2335 		rnd >>= 8;
2336 	}
2337 }
2338 #endif
2339 
2340 #define MAX_PACKETS	(1U<<31)
2341 int
ssh_packet_need_rekeying(ncrack_ssh_state * nstate)2342 ssh_packet_need_rekeying(ncrack_ssh_state *nstate)
2343 {
2344 	//struct session_state *state = ssh->state;
2345 
2346 	if (nstate->compat & SSH_BUG_NOREKEY)
2347 		return 0;
2348 	return
2349 	    (nstate->p_send.packets > MAX_PACKETS) ||
2350 	    (nstate->p_read.packets > MAX_PACKETS) ||
2351 	    (nstate->max_blocks_out &&
2352 	        (nstate->p_send.blocks > nstate->max_blocks_out)) ||
2353 	    (nstate->max_blocks_in &&
2354 	        (nstate->p_read.blocks > nstate->max_blocks_in)) ||
2355 	    (nstate->rekey_interval != 0 && nstate->rekey_time +
2356 		 nstate->rekey_interval <= monotime());
2357 }
2358 
2359 void
ssh_packet_set_rekey_limits(struct ssh * ssh,u_int32_t bytes,time_t seconds)2360 ssh_packet_set_rekey_limits(struct ssh *ssh, u_int32_t bytes, time_t seconds)
2361 {
2362 	debug3("rekey after %lld bytes, %d seconds", (long long)bytes,
2363 	    (int)seconds);
2364 	ssh->state->rekey_limit = bytes;
2365 	ssh->state->rekey_interval = seconds;
2366 }
2367 
2368 time_t
ssh_packet_get_rekey_timeout(struct ssh * ssh)2369 ssh_packet_get_rekey_timeout(struct ssh *ssh)
2370 {
2371 	time_t seconds;
2372 
2373 	seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
2374 	    monotime();
2375 	return (seconds <= 0 ? 1 : seconds);
2376 }
2377 
2378 void
ssh_packet_set_server(struct ssh * ssh)2379 ssh_packet_set_server(struct ssh *ssh)
2380 {
2381 	ssh->state->server_side = 1;
2382 }
2383 
2384 void
ssh_packet_set_authenticated(struct ssh * ssh)2385 ssh_packet_set_authenticated(struct ssh *ssh)
2386 {
2387 	ssh->state->after_authentication = 1;
2388 }
2389 
2390 void *
ssh_packet_get_input(struct ssh * ssh)2391 ssh_packet_get_input(struct ssh *ssh)
2392 {
2393 	return (void *)ssh->state->input;
2394 }
2395 
2396 void *
ssh_packet_get_output(struct ssh * ssh)2397 ssh_packet_get_output(struct ssh *ssh)
2398 {
2399 	return (void *)ssh->state->output;
2400 }
2401 
2402 #if 0
2403 /* XXX TODO update roaming to new API (does not work anyway) */
2404 /*
2405  * Save the state for the real connection, and use a separate state when
2406  * resuming a suspended connection.
2407  */
2408 void
2409 ssh_packet_backup_state(struct ssh *ssh,
2410     struct ssh *backup_state)
2411 {
2412 	struct ssh *tmp;
2413 
2414 	close(ssh->state->connection_in);
2415 	ssh->state->connection_in = -1;
2416 	close(ssh->state->connection_out);
2417 	ssh->state->connection_out = -1;
2418 	if (backup_state)
2419 		tmp = backup_state;
2420 	else
2421 		tmp = ssh_alloc_session_state();
2422 	backup_state = ssh;
2423 	ssh = tmp;
2424 }
2425 
2426 /* XXX FIXME FIXME FIXME */
2427 /*
2428  * Swap in the old state when resuming a connecion.
2429  */
2430 void
2431 ssh_packet_restore_state(struct ssh *ssh,
2432     struct ssh *backup_state)
2433 {
2434 	struct ssh *tmp;
2435 	u_int len;
2436 	int r;
2437 
2438 	tmp = backup_state;
2439 	backup_state = ssh;
2440 	ssh = tmp;
2441 	ssh->state->connection_in = backup_state->state->connection_in;
2442 	backup_state->state->connection_in = -1;
2443 	ssh->state->connection_out = backup_state->state->connection_out;
2444 	backup_state->state->connection_out = -1;
2445 	len = sshbuf_len(backup_state->state->input);
2446 	if (len > 0) {
2447 		if ((r = sshbuf_putb(ssh->state->input,
2448 		    backup_state->state->input)) != 0)
2449 			fatal("%s: %s", __func__, ssh_err(r));
2450 		sshbuf_reset(backup_state->state->input);
2451 		add_recv_bytes(len);
2452 	}
2453 }
2454 
2455 /* Reset after_authentication and reset compression in post-auth privsep */
2456 static int
2457 ssh_packet_set_postauth(struct ssh *ssh)
2458 {
2459 	struct sshcomp *comp;
2460 	int r, mode;
2461 
2462 	debug("%s: called", __func__);
2463 	/* This was set in net child, but is not visible in user child */
2464 	ssh->state->after_authentication = 1;
2465 	ssh->state->rekeying = 0;
2466 	for (mode = 0; mode < MODE_MAX; mode++) {
2467 		if (ssh->state->newkeys[mode] == NULL)
2468 			continue;
2469 		comp = &ssh->state->newkeys[mode]->comp;
2470 		if (comp && comp->enabled &&
2471 		    (r = ssh_packet_init_compression(ssh)) != 0)
2472 			return r;
2473 	}
2474 	return 0;
2475 }
2476 
2477 /* Packet state (de-)serialization for privsep */
2478 
2479 /* turn kex into a blob for packet state serialization */
2480 static int
2481 kex_to_blob(struct sshbuf *m, struct kex *kex)
2482 {
2483 	int r;
2484 
2485 	if ((r = sshbuf_put_string(m, kex->session_id,
2486 	    kex->session_id_len)) != 0 ||
2487 	    (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2488 	    (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2489 	    (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2490 	    (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2491 	    (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2492 	    (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2493 	    (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2494 	    (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2495 		return r;
2496 	return 0;
2497 }
2498 
2499 /* turn key exchange results into a blob for packet state serialization */
2500 static int
2501 newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2502 {
2503 	struct sshbuf *b;
2504 	struct sshcipher_ctx *cc;
2505 	struct sshcomp *comp;
2506 	struct sshenc *enc;
2507 	struct sshmac *mac;
2508 	struct newkeys *newkey;
2509 	int r;
2510 
2511 	if ((newkey = ssh->state->newkeys[mode]) == NULL)
2512 		return SSH_ERR_INTERNAL_ERROR;
2513 	enc = &newkey->enc;
2514 	mac = &newkey->mac;
2515 	comp = &newkey->comp;
2516 	cc = (mode == MODE_OUT) ? &ssh->state->send_context :
2517 	    &ssh->state->receive_context;
2518 	if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2519 		return r;
2520 	if ((b = sshbuf_new()) == NULL)
2521 		return SSH_ERR_ALLOC_FAIL;
2522 	/* The cipher struct is constant and shared, you export pointer */
2523 	if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2524 	    (r = sshbuf_put(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2525 	    (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2526 	    (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2527 	    (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2528 	    (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2529 		goto out;
2530 	if (cipher_authlen(enc->cipher) == 0) {
2531 		if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2532 		    (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2533 		    (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2534 			goto out;
2535 	}
2536 	if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2537 	    (r = sshbuf_put_u32(b, comp->enabled)) != 0 ||
2538 	    (r = sshbuf_put_cstring(b, comp->name)) != 0)
2539 		goto out;
2540 	r = sshbuf_put_stringb(m, b);
2541  out:
2542 	if (b != NULL)
2543 		sshbuf_free(b);
2544 	return r;
2545 }
2546 
2547 /* serialize packet state into a blob */
2548 int
2549 ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2550 {
2551 	struct session_state *state = ssh->state;
2552 	u_char *p;
2553 	size_t slen, rlen;
2554 	int r, ssh1cipher;
2555 
2556 	if (!compat20) {
2557 		ssh1cipher = cipher_get_number(state->receive_context.cipher);
2558 		slen = cipher_get_keyiv_len(&state->send_context);
2559 		rlen = cipher_get_keyiv_len(&state->receive_context);
2560 		if ((r = sshbuf_put_u32(m, state->remote_protocol_flags)) != 0 ||
2561 		    (r = sshbuf_put_u32(m, ssh1cipher)) != 0 ||
2562 		    (r = sshbuf_put_string(m, state->ssh1_key, state->ssh1_keylen)) != 0 ||
2563 		    (r = sshbuf_put_u32(m, slen)) != 0 ||
2564 		    (r = sshbuf_reserve(m, slen, &p)) != 0 ||
2565 		    (r = cipher_get_keyiv(&state->send_context, p, slen)) != 0 ||
2566 		    (r = sshbuf_put_u32(m, rlen)) != 0 ||
2567 		    (r = sshbuf_reserve(m, rlen, &p)) != 0 ||
2568 		    (r = cipher_get_keyiv(&state->receive_context, p, rlen)) != 0)
2569 			return r;
2570 	} else {
2571 		if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2572 		    (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2573 		    (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
2574 		    (r = sshbuf_put_u32(m, state->rekey_limit)) != 0 ||
2575 		    (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
2576 		    (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2577 		    (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2578 		    (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2579 		    (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2580 		    (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2581 		    (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2582 		    (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2583 		    (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0)
2584 			return r;
2585 	}
2586 
2587 	slen = cipher_get_keycontext(&state->send_context, NULL);
2588 	rlen = cipher_get_keycontext(&state->receive_context, NULL);
2589 	if ((r = sshbuf_put_u32(m, slen)) != 0 ||
2590 	    (r = sshbuf_reserve(m, slen, &p)) != 0)
2591 		return r;
2592 	if (cipher_get_keycontext(&state->send_context, p) != (int)slen)
2593 		return SSH_ERR_INTERNAL_ERROR;
2594 	if ((r = sshbuf_put_u32(m, rlen)) != 0 ||
2595 	    (r = sshbuf_reserve(m, rlen, &p)) != 0)
2596 		return r;
2597 	if (cipher_get_keycontext(&state->receive_context, p) != (int)rlen)
2598 		return SSH_ERR_INTERNAL_ERROR;
2599 
2600 	if ((r = ssh_packet_get_compress_state(m, ssh)) != 0 ||
2601 	    (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2602 	    (r = sshbuf_put_stringb(m, state->output)) != 0)
2603 		return r;
2604 
2605 	if (compat20) {
2606 		if ((r = sshbuf_put_u64(m, get_sent_bytes())) != 0 ||
2607 		    (r = sshbuf_put_u64(m, get_recv_bytes())) != 0)
2608 			return r;
2609 	}
2610 	return 0;
2611 }
2612 #endif
2613 
2614 #if 0
2615 /* restore key exchange results from blob for packet state de-serialization */
2616 static int
2617 newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2618 {
2619 	struct sshbuf *b = NULL;
2620 	struct sshcomp *comp;
2621 	struct sshenc *enc;
2622 	struct sshmac *mac;
2623 	struct newkeys *newkey = NULL;
2624 	size_t keylen, ivlen, maclen;
2625 	int r;
2626 
2627 	if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2628 		r = SSH_ERR_ALLOC_FAIL;
2629 		goto out;
2630 	}
2631 	if ((r = sshbuf_froms(m, &b)) != 0)
2632 		goto out;
2633 #ifdef DEBUG_PK
2634 	sshbuf_dump(b, stderr);
2635 #endif
2636 	enc = &newkey->enc;
2637 	mac = &newkey->mac;
2638 	comp = &newkey->comp;
2639 
2640 	if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2641 	    (r = sshbuf_get(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2642 	    (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2643 	    (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2644 	    (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2645 	    (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2646 		goto out;
2647 	if (cipher_authlen(enc->cipher) == 0) {
2648 		if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2649 			goto out;
2650 		if ((r = mac_setup(mac, mac->name)) != 0)
2651 			goto out;
2652 		if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2653 		    (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2654 			goto out;
2655 		if (maclen > mac->key_len) {
2656 			r = SSH_ERR_INVALID_FORMAT;
2657 			goto out;
2658 		}
2659 		mac->key_len = maclen;
2660 	}
2661 	if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2662 	    (r = sshbuf_get_u32(b, (u_int *)&comp->enabled)) != 0 ||
2663 	    (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2664 		goto out;
2665 	if (enc->name == NULL ||
2666 	    cipher_by_name(enc->name) != enc->cipher) {
2667 		r = SSH_ERR_INVALID_FORMAT;
2668 		goto out;
2669 	}
2670 	if (sshbuf_len(b) != 0) {
2671 		r = SSH_ERR_INVALID_FORMAT;
2672 		goto out;
2673 	}
2674 	enc->key_len = keylen;
2675 	enc->iv_len = ivlen;
2676 	ssh->kex->newkeys[mode] = newkey;
2677 	newkey = NULL;
2678 	r = 0;
2679  out:
2680 	if (newkey != NULL)
2681 		free(newkey);
2682 	if (b != NULL)
2683 		sshbuf_free(b);
2684 	return r;
2685 }
2686 
2687 /* restore kex from blob for packet state de-serialization */
2688 static int
2689 kex_from_blob(struct sshbuf *m, struct kex **kexp)
2690 {
2691 	struct kex *kex;
2692 	int r;
2693 
2694 	if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2695 	    (kex->my = sshbuf_new()) == NULL ||
2696 	    (kex->peer = sshbuf_new()) == NULL) {
2697 		r = SSH_ERR_ALLOC_FAIL;
2698 		goto out;
2699 	}
2700 	if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2701 	    (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2702 	    (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2703 	    (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2704 	    (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2705 	    (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2706 	    (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2707 	    (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2708 	    (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2709 		goto out;
2710 	kex->server = 1;
2711 	kex->done = 1;
2712 	r = 0;
2713  out:
2714 	if (r != 0 || kexp == NULL) {
2715 		if (kex != NULL) {
2716 			if (kex->my != NULL)
2717 				sshbuf_free(kex->my);
2718 			if (kex->peer != NULL)
2719 				sshbuf_free(kex->peer);
2720 			free(kex);
2721 		}
2722 		if (kexp != NULL)
2723 			*kexp = NULL;
2724 	} else {
2725 		*kexp = kex;
2726 	}
2727 	return r;
2728 }
2729 
2730 /*
2731  * Restore packet state from content of blob 'm' (de-serialization).
2732  * Note that 'm' will be partially consumed on parsing or any other errors.
2733  */
2734 int
2735 ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2736 {
2737 #if 0
2738 	struct session_state *state = ssh->state;
2739 	const u_char *ssh1key, *ivin, *ivout, *keyin, *keyout, *input, *output;
2740 	size_t ssh1keylen, rlen, slen, ilen, olen;
2741 	int r;
2742 	u_int ssh1cipher = 0;
2743 	u_int64_t sent_bytes = 0, recv_bytes = 0;
2744 
2745 	if (!compat20) {
2746 		if ((r = sshbuf_get_u32(m, &state->remote_protocol_flags)) != 0 ||
2747 		    (r = sshbuf_get_u32(m, &ssh1cipher)) != 0 ||
2748 		    (r = sshbuf_get_string_direct(m, &ssh1key, &ssh1keylen)) != 0 ||
2749 		    (r = sshbuf_get_string_direct(m, &ivout, &slen)) != 0 ||
2750 		    (r = sshbuf_get_string_direct(m, &ivin, &rlen)) != 0)
2751 			return r;
2752 		if (ssh1cipher > INT_MAX)
2753 			return SSH_ERR_KEY_UNKNOWN_CIPHER;
2754 		ssh_packet_set_encryption_key(ssh, ssh1key, ssh1keylen,
2755 		    (int)ssh1cipher);
2756 		if (cipher_get_keyiv_len(&state->send_context) != (int)slen ||
2757 		    cipher_get_keyiv_len(&state->receive_context) != (int)rlen)
2758 			return SSH_ERR_INVALID_FORMAT;
2759 		if ((r = cipher_set_keyiv(&state->send_context, ivout)) != 0 ||
2760 		    (r = cipher_set_keyiv(&state->receive_context, ivin)) != 0)
2761 			return r;
2762 	} else {
2763 		if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2764 		    (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2765 		    (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
2766 		    (r = sshbuf_get_u32(m, &state->rekey_limit)) != 0 ||
2767 		    (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
2768 		    (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2769 		    (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2770 		    (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2771 		    (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2772 		    (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2773 		    (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2774 		    (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2775 		    (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2776 			return r;
2777 		/*
2778 		 * We set the time here so that in post-auth privsep slave we
2779 		 * count from the completion of the authentication.
2780 		 */
2781 		state->rekey_time = monotime();
2782 		/* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2783 		if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2784 		    (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2785 			return r;
2786 	}
2787 	if ((r = sshbuf_get_string_direct(m, &keyout, &slen)) != 0 ||
2788 	    (r = sshbuf_get_string_direct(m, &keyin, &rlen)) != 0)
2789 		return r;
2790 	if (cipher_get_keycontext(&state->send_context, NULL) != (int)slen ||
2791 	    cipher_get_keycontext(&state->receive_context, NULL) != (int)rlen)
2792 		return SSH_ERR_INVALID_FORMAT;
2793 	cipher_set_keycontext(&state->send_context, keyout);
2794 	cipher_set_keycontext(&state->receive_context, keyin);
2795 
2796 	if ((r = ssh_packet_set_compress_state(ssh, m)) != 0 ||
2797 	    (r = ssh_packet_set_postauth(ssh)) != 0)
2798 		return r;
2799 
2800 	sshbuf_reset(state->input);
2801 	sshbuf_reset(state->output);
2802 	if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2803 	    (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2804 	    (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2805 	    (r = sshbuf_put(state->output, output, olen)) != 0)
2806 		return r;
2807 
2808 	if (compat20) {
2809 		if ((r = sshbuf_get_u64(m, &sent_bytes)) != 0 ||
2810 		    (r = sshbuf_get_u64(m, &recv_bytes)) != 0)
2811 			return r;
2812 		roam_set_bytes(sent_bytes, recv_bytes);
2813 	}
2814 	if (sshbuf_len(m))
2815 		return SSH_ERR_INVALID_FORMAT;
2816 	debug3("%s: done", __func__);
2817 	return 0;
2818 #endif
2819 }
2820 #endif
2821 
2822 /* NEW API */
2823 
2824 /* put data to the outgoing packet */
2825 
2826 int
sshpkt_put(ncrack_ssh_state * nstate,const void * v,size_t len)2827 sshpkt_put(ncrack_ssh_state *nstate, const void *v, size_t len)
2828 {
2829 	return sshbuf_put(nstate->outgoing_packet, v, len);
2830 }
2831 
2832 
2833 int
sshpkt_putb(ncrack_ssh_state * nstate,const struct sshbuf * b)2834 sshpkt_putb(ncrack_ssh_state *nstate, const struct sshbuf *b)
2835 {
2836 	return sshbuf_putb(nstate->outgoing_packet, b);
2837 }
2838 
2839 
2840 int
sshpkt_put_u8(ncrack_ssh_state * nstate,u_char val)2841 sshpkt_put_u8(ncrack_ssh_state *nstate, u_char val)
2842 {
2843 	return sshbuf_put_u8(nstate->outgoing_packet, val);
2844 }
2845 
2846 int
sshpkt_put_u32(ncrack_ssh_state * nstate,u_int32_t val)2847 sshpkt_put_u32(ncrack_ssh_state *nstate, u_int32_t val)
2848 {
2849 	return sshbuf_put_u32(nstate->outgoing_packet, val);
2850 }
2851 
2852 int
sshpkt_put_u64(ncrack_ssh_state * nstate,u_int64_t val)2853 sshpkt_put_u64(ncrack_ssh_state *nstate, u_int64_t val)
2854 {
2855 	return sshbuf_put_u64(nstate->outgoing_packet, val);
2856 }
2857 
2858 int
sshpkt_put_string(ncrack_ssh_state * nstate,const void * v,size_t len)2859 sshpkt_put_string(ncrack_ssh_state *nstate, const void *v, size_t len)
2860 {
2861 	return sshbuf_put_string(nstate->outgoing_packet, v, len);
2862 }
2863 
2864 int
sshpkt_put_cstring(ncrack_ssh_state * nstate,const void * v)2865 sshpkt_put_cstring(ncrack_ssh_state *nstate, const void *v)
2866 {
2867 	return sshbuf_put_cstring(nstate->outgoing_packet, v);
2868 }
2869 
2870 int
sshpkt_put_stringb(ncrack_ssh_state * nstate,const struct sshbuf * v)2871 sshpkt_put_stringb(ncrack_ssh_state *nstate, const struct sshbuf *v)
2872 {
2873 	return sshbuf_put_stringb(nstate->outgoing_packet, v);
2874 }
2875 
2876 #ifdef WITH_OPENSSL
2877 #ifdef OPENSSL_HAS_ECC
2878 int
sshpkt_put_ec(ncrack_ssh_state * nstate,const EC_POINT * v,const EC_GROUP * g)2879 sshpkt_put_ec(ncrack_ssh_state *nstate, const EC_POINT *v, const EC_GROUP *g)
2880 {
2881 	return sshbuf_put_ec(nstate->outgoing_packet, v, g);
2882 }
2883 #endif /* OPENSSL_HAS_ECC */
2884 
2885 #ifdef WITH_SSH1
2886 int
sshpkt_put_bignum1(ncrack_ssh_state * nstate,const BIGNUM * v)2887 sshpkt_put_bignum1(ncrack_ssh_state *nstate, const BIGNUM *v)
2888 {
2889 	return sshbuf_put_bignum1(nstate->outgoing_packet, v);
2890 }
2891 #endif /* WITH_SSH1 */
2892 
2893 int
sshpkt_put_bignum2(ncrack_ssh_state * nstate,const BIGNUM * v)2894 sshpkt_put_bignum2(ncrack_ssh_state *nstate, const BIGNUM *v)
2895 {
2896 	return sshbuf_put_bignum2(nstate->outgoing_packet, v);
2897 }
2898 #endif /* WITH_OPENSSL */
2899 
2900 /* fetch data from the incoming packet */
2901 
2902 int
sshpkt_get(ncrack_ssh_state * nstate,void * valp,size_t len)2903 sshpkt_get(ncrack_ssh_state *nstate, void *valp, size_t len)
2904 {
2905 	return sshbuf_get(nstate->incoming_packet, valp, len);
2906 }
2907 
2908 int
sshpkt_get_u8(ncrack_ssh_state * nstate,u_char * valp)2909 sshpkt_get_u8(ncrack_ssh_state *nstate, u_char *valp)
2910 {
2911 	return sshbuf_get_u8(nstate->incoming_packet, valp);
2912 }
2913 
2914 int
sshpkt_get_u32(ncrack_ssh_state * nstate,u_int32_t * valp)2915 sshpkt_get_u32(ncrack_ssh_state *nstate, u_int32_t *valp)
2916 {
2917 	return sshbuf_get_u32(nstate->incoming_packet, valp);
2918 }
2919 
2920 int
sshpkt_get_u64(ncrack_ssh_state * nstate,u_int64_t * valp)2921 sshpkt_get_u64(ncrack_ssh_state *nstate, u_int64_t *valp)
2922 {
2923 	return sshbuf_get_u64(nstate->incoming_packet, valp);
2924 }
2925 
2926 int
sshpkt_get_string(ncrack_ssh_state * nstate,u_char ** valp,size_t * lenp)2927 sshpkt_get_string(ncrack_ssh_state *nstate, u_char **valp, size_t *lenp)
2928 {
2929 	return sshbuf_get_string(nstate->incoming_packet, valp, lenp);
2930 }
2931 
2932 int
sshpkt_get_string_direct(ncrack_ssh_state * nstate,const u_char ** valp,size_t * lenp)2933 sshpkt_get_string_direct(ncrack_ssh_state *nstate, const u_char **valp, size_t *lenp)
2934 {
2935 	return sshbuf_get_string_direct(nstate->incoming_packet, valp, lenp);
2936 }
2937 
2938 int
sshpkt_get_cstring(ncrack_ssh_state * nstate,char ** valp,size_t * lenp)2939 sshpkt_get_cstring(ncrack_ssh_state *nstate, char **valp, size_t *lenp)
2940 {
2941 	return sshbuf_get_cstring(nstate->incoming_packet, valp, lenp);
2942 }
2943 
2944 #ifdef WITH_OPENSSL
2945 #ifdef OPENSSL_HAS_ECC
2946 int
sshpkt_get_ec(ncrack_ssh_state * nstate,EC_POINT * v,const EC_GROUP * g)2947 sshpkt_get_ec(ncrack_ssh_state *nstate, EC_POINT *v, const EC_GROUP *g)
2948 {
2949 	return sshbuf_get_ec(nstate->incoming_packet, v, g);
2950 }
2951 #endif /* OPENSSL_HAS_ECC */
2952 
2953 #ifdef WITH_SSH1
2954 int
sshpkt_get_bignum1(ncrack_ssh_state * nstate,BIGNUM * v)2955 sshpkt_get_bignum1(ncrack_ssh_state *nstate, BIGNUM *v)
2956 {
2957 	return sshbuf_get_bignum1(nstate->incoming_packet, v);
2958 }
2959 #endif /* WITH_SSH1 */
2960 
2961 int
sshpkt_get_bignum2(ncrack_ssh_state * nstate,BIGNUM * v)2962 sshpkt_get_bignum2(ncrack_ssh_state *nstate, BIGNUM *v)
2963 {
2964 	return sshbuf_get_bignum2(nstate->incoming_packet, v);
2965 }
2966 #endif /* WITH_OPENSSL */
2967 
2968 int
sshpkt_get_end(ncrack_ssh_state * nstate)2969 sshpkt_get_end(ncrack_ssh_state *nstate)
2970 {
2971 	if (sshbuf_len(nstate->incoming_packet) > 0)
2972 		return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2973 	return 0;
2974 }
2975 
2976 const u_char *
sshpkt_ptr(ncrack_ssh_state * nstate,size_t * lenp)2977 sshpkt_ptr(ncrack_ssh_state *nstate, size_t *lenp)
2978 {
2979 	if (lenp != NULL)
2980 		*lenp = sshbuf_len(nstate->incoming_packet);
2981 	return sshbuf_ptr(nstate->incoming_packet);
2982 }
2983 
2984 
2985 
2986 /* start a new packet */
2987 
2988 int
sshpkt_start(ncrack_ssh_state * nstate,u_char type)2989 sshpkt_start(ncrack_ssh_state *nstate, u_char type)
2990 {
2991 	u_char buf[9];
2992 	int len;
2993 
2994 
2995   // NCRACK: INITIALIZE COMPAT20 HERE FOR NOW
2996 	nstate->compat20 = 1;
2997 	nstate->packet_length = 0;
2998   nstate->packlen = 0;
2999 
3000 
3001 	DBG(debug("packet_start[%d]", type));
3002 	len = nstate->compat20 ? 6 : 9;
3003 	memset(buf, 0, len - 1);
3004 	buf[len - 1] = type;
3005 	sshbuf_reset(nstate->outgoing_packet);
3006 	return sshbuf_put(nstate->outgoing_packet, buf, len);
3007 }
3008 
3009 
3010 /* send it */
3011 
3012 int
sshpkt_send(ncrack_ssh_state * nstate)3013 sshpkt_send(ncrack_ssh_state *nstate)
3014 {
3015 	if (nstate->compat20)
3016 		return ssh_packet_send2(nstate);
3017 	else
3018 		return ssh_packet_send1(nstate);
3019 }
3020 
3021 int
sshpkt_disconnect(ncrack_ssh_state * nstate,const char * fmt,...)3022 sshpkt_disconnect(ncrack_ssh_state *nstate, const char *fmt,...)
3023 {
3024 	char buf[1024];
3025 	va_list args;
3026 	int r;
3027 
3028 	va_start(args, fmt);
3029 	vsnprintf(buf, sizeof(buf), fmt, args);
3030 	va_end(args);
3031 
3032 	if (compat20) {
3033 		if ((r = sshpkt_start(nstate, SSH2_MSG_DISCONNECT)) != 0 ||
3034 		    (r = sshpkt_put_u32(nstate, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
3035 		    (r = sshpkt_put_cstring(nstate, buf)) != 0 ||
3036 		    (r = sshpkt_put_cstring(nstate, "")) != 0 ||
3037 		    (r = sshpkt_send(nstate)) != 0)
3038 			return r;
3039 	} else {
3040 		if ((r = sshpkt_start(nstate, SSH_MSG_DISCONNECT)) != 0 ||
3041 		    (r = sshpkt_put_cstring(nstate, buf)) != 0 ||
3042 		    (r = sshpkt_send(nstate)) != 0)
3043 			return r;
3044 	}
3045 	return 0;
3046 }
3047 
3048 /* roundup current message to pad bytes */
3049 int
sshpkt_add_padding(ncrack_ssh_state * nstate,u_char pad)3050 sshpkt_add_padding(ncrack_ssh_state *nstate, u_char pad)
3051 {
3052 	nstate->extra_pad = pad;
3053 	return 0;
3054 }
3055 
3056 
3057