1 /* $OpenBSD: packet.c,v 1.264 2017/09/12 06:32:07 djm Exp $ */
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
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.
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".
16 * SSH2 packet format added by Markus Friedl.
17 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
19 * Redistribution and use in source and binary forms, with or without
20 * modification, are permitted provided that the following conditions
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.
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.
43 #include <sys/types.h>
44 #include "openbsd-compat/sys-queue.h"
45 #include <sys/socket.h>
46 #ifdef HAVE_SYS_TIME_H
47 # include <sys/time.h>
50 #include <netinet/in.h>
51 #include <netinet/ip.h>
52 #include <arpa/inet.h>
67 #include "buffer.h" /* typedefs XXX */
68 #include "key.h" /* typedefs XXX */
87 #include "blacklist_client.h"
95 #define PACKET_MAX_SIZE (256 * 1024)
105 TAILQ_ENTRY(packet) next;
107 struct sshbuf *payload;
110 struct session_state {
112 * This variable contains the file descriptors used for
113 * communicating with the other side. connection_in is used for
114 * reading; connection_out for writing. These can be the same
115 * descriptor, in which case it is assumed to be a socket.
120 /* Protocol flags for the remote side. */
121 u_int remote_protocol_flags;
123 /* Encryption context for receiving data. Only used for decryption. */
124 struct sshcipher_ctx *receive_context;
126 /* Encryption context for sending data. Only used for encryption. */
127 struct sshcipher_ctx *send_context;
129 /* Buffer for raw input data from the socket. */
130 struct sshbuf *input;
132 /* Buffer for raw output data going to the socket. */
133 struct sshbuf *output;
135 /* Buffer for the partial outgoing packet being constructed. */
136 struct sshbuf *outgoing_packet;
138 /* Buffer for the incoming packet currently being processed. */
139 struct sshbuf *incoming_packet;
141 /* Scratch buffer for packet compression/decompression. */
142 struct sshbuf *compression_buffer;
144 /* Incoming/outgoing compression dictionaries */
145 z_stream compression_in_stream;
146 z_stream compression_out_stream;
147 int compression_in_started;
148 int compression_out_started;
149 int compression_in_failures;
150 int compression_out_failures;
153 * Flag indicating whether packet compression/decompression is
156 int packet_compression;
158 /* default maximum packet size */
159 u_int max_packet_size;
161 /* Flag indicating whether this module has been initialized. */
164 /* Set to true if the connection is interactive. */
165 int interactive_mode;
167 /* Set to true if we are the server side. */
170 /* Set to true if we are authenticated. */
171 int after_authentication;
173 int keep_alive_timeouts;
175 /* The maximum time that we will wait to send or receive a packet */
176 int packet_timeout_ms;
178 /* Session key information for Encryption and MAC */
179 struct newkeys *newkeys[MODE_MAX];
180 struct packet_state p_read, p_send;
182 /* Volume-based rekeying */
183 u_int64_t max_blocks_in, max_blocks_out, rekey_limit;
185 /* Time-based rekeying */
186 u_int32_t rekey_interval; /* how often in seconds */
187 time_t rekey_time; /* time of last rekeying */
189 /* roundup current message to extra_pad bytes */
192 /* XXX discard incoming data after MAC error */
193 u_int packet_discard;
194 size_t packet_discard_mac_already;
195 struct sshmac *packet_discard_mac;
197 /* Used in packet_read_poll2() */
200 /* Used in packet_send2 */
203 /* Used in ssh_packet_send_mux() */
206 /* Used in packet_set_interactive */
207 int set_interactive_called;
209 /* Used in packet_set_maxsize */
210 int set_maxsize_called;
212 /* One-off warning about weak ciphers */
213 int cipher_warning_done;
215 /* Hook for fuzzing inbound packets */
216 ssh_packet_hook_fn *hook_in;
219 TAILQ_HEAD(, packet) outgoing;
223 ssh_alloc_session_state(void)
225 struct ssh *ssh = NULL;
226 struct session_state *state = NULL;
228 if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
229 (state = calloc(1, sizeof(*state))) == NULL ||
230 (state->input = sshbuf_new()) == NULL ||
231 (state->output = sshbuf_new()) == NULL ||
232 (state->outgoing_packet = sshbuf_new()) == NULL ||
233 (state->incoming_packet = sshbuf_new()) == NULL)
235 TAILQ_INIT(&state->outgoing);
236 TAILQ_INIT(&ssh->private_keys);
237 TAILQ_INIT(&ssh->public_keys);
238 state->connection_in = -1;
239 state->connection_out = -1;
240 state->max_packet_size = 32768;
241 state->packet_timeout_ms = -1;
242 state->p_send.packets = state->p_read.packets = 0;
243 state->initialized = 1;
245 * ssh_packet_send2() needs to queue packets until
246 * we've done the initial key exchange.
253 sshbuf_free(state->input);
254 sshbuf_free(state->output);
255 sshbuf_free(state->incoming_packet);
256 sshbuf_free(state->outgoing_packet);
264 ssh_packet_set_input_hook(struct ssh *ssh, ssh_packet_hook_fn *hook, void *ctx)
266 ssh->state->hook_in = hook;
267 ssh->state->hook_in_ctx = ctx;
270 /* Returns nonzero if rekeying is in progress */
272 ssh_packet_is_rekeying(struct ssh *ssh)
274 return ssh->state->rekeying ||
275 (ssh->kex != NULL && ssh->kex->done == 0);
279 * Sets the descriptors used for communication.
282 ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
284 struct session_state *state;
285 const struct sshcipher *none = cipher_by_name("none");
289 error("%s: cannot load cipher 'none'", __func__);
293 ssh = ssh_alloc_session_state();
295 error("%s: cound not allocate state", __func__);
299 state->connection_in = fd_in;
300 state->connection_out = fd_out;
301 if ((r = cipher_init(&state->send_context, none,
302 (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
303 (r = cipher_init(&state->receive_context, none,
304 (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
305 error("%s: cipher_init failed: %s", __func__, ssh_err(r));
306 free(ssh); /* XXX need ssh_free_session_state? */
309 state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
311 * Cache the IP address of the remote connection for use in error
312 * messages that might be generated after the connection has closed.
314 (void)ssh_remote_ipaddr(ssh);
319 ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
321 struct session_state *state = ssh->state;
323 if (timeout <= 0 || count <= 0) {
324 state->packet_timeout_ms = -1;
327 if ((INT_MAX / 1000) / count < timeout)
328 state->packet_timeout_ms = INT_MAX;
330 state->packet_timeout_ms = timeout * count * 1000;
334 ssh_packet_set_mux(struct ssh *ssh)
337 ssh->state->rekeying = 0;
341 ssh_packet_get_mux(struct ssh *ssh)
343 return ssh->state->mux;
347 ssh_packet_set_log_preamble(struct ssh *ssh, const char *fmt, ...)
352 free(ssh->log_preamble);
354 ssh->log_preamble = NULL;
357 r = vasprintf(&ssh->log_preamble, fmt, args);
359 if (r < 0 || ssh->log_preamble == NULL)
360 return SSH_ERR_ALLOC_FAIL;
366 ssh_packet_stop_discard(struct ssh *ssh)
368 struct session_state *state = ssh->state;
371 if (state->packet_discard_mac) {
373 size_t dlen = PACKET_MAX_SIZE;
375 if (dlen > state->packet_discard_mac_already)
376 dlen -= state->packet_discard_mac_already;
377 memset(buf, 'a', sizeof(buf));
378 while (sshbuf_len(state->incoming_packet) < dlen)
379 if ((r = sshbuf_put(state->incoming_packet, buf,
382 (void) mac_compute(state->packet_discard_mac,
384 sshbuf_ptr(state->incoming_packet), dlen,
387 logit("Finished discarding for %.200s port %d",
388 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
389 return SSH_ERR_MAC_INVALID;
393 ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
394 struct sshmac *mac, size_t mac_already, u_int discard)
396 struct session_state *state = ssh->state;
399 if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
400 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
402 return SSH_ERR_MAC_INVALID;
405 * Record number of bytes over which the mac has already
406 * been computed in order to minimize timing attacks.
408 if (mac && mac->enabled) {
409 state->packet_discard_mac = mac;
410 state->packet_discard_mac_already = mac_already;
412 if (sshbuf_len(state->input) >= discard)
413 return ssh_packet_stop_discard(ssh);
414 state->packet_discard = discard - sshbuf_len(state->input);
418 /* Returns 1 if remote host is connected via socket, 0 if not. */
421 ssh_packet_connection_is_on_socket(struct ssh *ssh)
423 struct session_state *state = ssh->state;
424 struct sockaddr_storage from, to;
425 socklen_t fromlen, tolen;
427 if (state->connection_in == -1 || state->connection_out == -1)
430 /* filedescriptors in and out are the same, so it's a socket */
431 if (state->connection_in == state->connection_out)
433 fromlen = sizeof(from);
434 memset(&from, 0, sizeof(from));
435 if (getpeername(state->connection_in, (struct sockaddr *)&from,
439 memset(&to, 0, sizeof(to));
440 if (getpeername(state->connection_out, (struct sockaddr *)&to,
443 if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
445 if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
451 ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
454 *ibytes = ssh->state->p_read.bytes;
456 *obytes = ssh->state->p_send.bytes;
460 ssh_packet_connection_af(struct ssh *ssh)
462 struct sockaddr_storage to;
463 socklen_t tolen = sizeof(to);
465 memset(&to, 0, sizeof(to));
466 if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
470 if (to.ss_family == AF_INET6 &&
471 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr))
477 /* Sets the connection into non-blocking mode. */
480 ssh_packet_set_nonblocking(struct ssh *ssh)
482 /* Set the socket into non-blocking mode. */
483 set_nonblock(ssh->state->connection_in);
485 if (ssh->state->connection_out != ssh->state->connection_in)
486 set_nonblock(ssh->state->connection_out);
489 /* Returns the socket used for reading. */
492 ssh_packet_get_connection_in(struct ssh *ssh)
494 return ssh->state->connection_in;
497 /* Returns the descriptor used for writing. */
500 ssh_packet_get_connection_out(struct ssh *ssh)
502 return ssh->state->connection_out;
506 * Returns the IP-address of the remote host as a string. The returned
507 * string must not be freed.
511 ssh_remote_ipaddr(struct ssh *ssh)
513 const int sock = ssh->state->connection_in;
515 /* Check whether we have cached the ipaddr. */
516 if (ssh->remote_ipaddr == NULL) {
517 if (ssh_packet_connection_is_on_socket(ssh)) {
518 ssh->remote_ipaddr = get_peer_ipaddr(sock);
519 ssh->remote_port = get_peer_port(sock);
520 ssh->local_ipaddr = get_local_ipaddr(sock);
521 ssh->local_port = get_local_port(sock);
523 ssh->remote_ipaddr = strdup("UNKNOWN");
524 ssh->remote_port = 65535;
525 ssh->local_ipaddr = strdup("UNKNOWN");
526 ssh->local_port = 65535;
529 return ssh->remote_ipaddr;
532 /* Returns the port number of the remote host. */
535 ssh_remote_port(struct ssh *ssh)
537 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
538 return ssh->remote_port;
542 * Returns the IP-address of the local host as a string. The returned
543 * string must not be freed.
547 ssh_local_ipaddr(struct ssh *ssh)
549 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
550 return ssh->local_ipaddr;
553 /* Returns the port number of the local host. */
556 ssh_local_port(struct ssh *ssh)
558 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
559 return ssh->local_port;
562 /* Closes the connection and clears and frees internal data structures. */
565 ssh_packet_close_internal(struct ssh *ssh, int do_close)
567 struct session_state *state = ssh->state;
570 if (!state->initialized)
572 state->initialized = 0;
574 if (state->connection_in == state->connection_out) {
575 close(state->connection_out);
577 close(state->connection_in);
578 close(state->connection_out);
581 sshbuf_free(state->input);
582 sshbuf_free(state->output);
583 sshbuf_free(state->outgoing_packet);
584 sshbuf_free(state->incoming_packet);
585 for (mode = 0; mode < MODE_MAX; mode++) {
586 kex_free_newkeys(state->newkeys[mode]); /* current keys */
587 state->newkeys[mode] = NULL;
588 ssh_clear_newkeys(ssh, mode); /* next keys */
590 /* comression state is in shared mem, so we can only release it once */
591 if (do_close && state->compression_buffer) {
592 sshbuf_free(state->compression_buffer);
593 if (state->compression_out_started) {
594 z_streamp stream = &state->compression_out_stream;
595 debug("compress outgoing: "
596 "raw data %llu, compressed %llu, factor %.2f",
597 (unsigned long long)stream->total_in,
598 (unsigned long long)stream->total_out,
599 stream->total_in == 0 ? 0.0 :
600 (double) stream->total_out / stream->total_in);
601 if (state->compression_out_failures == 0)
604 if (state->compression_in_started) {
605 z_streamp stream = &state->compression_in_stream;
606 debug("compress incoming: "
607 "raw data %llu, compressed %llu, factor %.2f",
608 (unsigned long long)stream->total_out,
609 (unsigned long long)stream->total_in,
610 stream->total_out == 0 ? 0.0 :
611 (double) stream->total_in / stream->total_out);
612 if (state->compression_in_failures == 0)
616 cipher_free(state->send_context);
617 cipher_free(state->receive_context);
618 state->send_context = state->receive_context = NULL;
620 free(ssh->remote_ipaddr);
621 ssh->remote_ipaddr = NULL;
628 ssh_packet_close(struct ssh *ssh)
630 ssh_packet_close_internal(ssh, 1);
634 ssh_packet_clear_keys(struct ssh *ssh)
636 ssh_packet_close_internal(ssh, 0);
639 /* Sets remote side protocol flags. */
642 ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
644 ssh->state->remote_protocol_flags = protocol_flags;
647 /* Returns the remote protocol flags set earlier by the above function. */
650 ssh_packet_get_protocol_flags(struct ssh *ssh)
652 return ssh->state->remote_protocol_flags;
656 * Starts packet compression from the next packet on in both directions.
657 * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
661 ssh_packet_init_compression(struct ssh *ssh)
663 if (!ssh->state->compression_buffer &&
664 ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
665 return SSH_ERR_ALLOC_FAIL;
670 start_compression_out(struct ssh *ssh, int level)
672 if (level < 1 || level > 9)
673 return SSH_ERR_INVALID_ARGUMENT;
674 debug("Enabling compression at level %d.", level);
675 if (ssh->state->compression_out_started == 1)
676 deflateEnd(&ssh->state->compression_out_stream);
677 switch (deflateInit(&ssh->state->compression_out_stream, level)) {
679 ssh->state->compression_out_started = 1;
682 return SSH_ERR_ALLOC_FAIL;
684 return SSH_ERR_INTERNAL_ERROR;
690 start_compression_in(struct ssh *ssh)
692 if (ssh->state->compression_in_started == 1)
693 inflateEnd(&ssh->state->compression_in_stream);
694 switch (inflateInit(&ssh->state->compression_in_stream)) {
696 ssh->state->compression_in_started = 1;
699 return SSH_ERR_ALLOC_FAIL;
701 return SSH_ERR_INTERNAL_ERROR;
707 ssh_packet_start_compression(struct ssh *ssh, int level)
711 if (ssh->state->packet_compression)
712 return SSH_ERR_INTERNAL_ERROR;
713 ssh->state->packet_compression = 1;
714 if ((r = ssh_packet_init_compression(ssh)) != 0 ||
715 (r = start_compression_in(ssh)) != 0 ||
716 (r = start_compression_out(ssh, level)) != 0)
721 /* XXX remove need for separate compression buffer */
723 compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
728 if (ssh->state->compression_out_started != 1)
729 return SSH_ERR_INTERNAL_ERROR;
731 /* This case is not handled below. */
732 if (sshbuf_len(in) == 0)
735 /* Input is the contents of the input buffer. */
736 if ((ssh->state->compression_out_stream.next_in =
737 sshbuf_mutable_ptr(in)) == NULL)
738 return SSH_ERR_INTERNAL_ERROR;
739 ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
741 /* Loop compressing until deflate() returns with avail_out != 0. */
743 /* Set up fixed-size output buffer. */
744 ssh->state->compression_out_stream.next_out = buf;
745 ssh->state->compression_out_stream.avail_out = sizeof(buf);
747 /* Compress as much data into the buffer as possible. */
748 status = deflate(&ssh->state->compression_out_stream,
752 return SSH_ERR_ALLOC_FAIL;
754 /* Append compressed data to output_buffer. */
755 if ((r = sshbuf_put(out, buf, sizeof(buf) -
756 ssh->state->compression_out_stream.avail_out)) != 0)
761 ssh->state->compression_out_failures++;
762 return SSH_ERR_INVALID_FORMAT;
764 } while (ssh->state->compression_out_stream.avail_out == 0);
769 uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
774 if (ssh->state->compression_in_started != 1)
775 return SSH_ERR_INTERNAL_ERROR;
777 if ((ssh->state->compression_in_stream.next_in =
778 sshbuf_mutable_ptr(in)) == NULL)
779 return SSH_ERR_INTERNAL_ERROR;
780 ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
783 /* Set up fixed-size output buffer. */
784 ssh->state->compression_in_stream.next_out = buf;
785 ssh->state->compression_in_stream.avail_out = sizeof(buf);
787 status = inflate(&ssh->state->compression_in_stream,
791 if ((r = sshbuf_put(out, buf, sizeof(buf) -
792 ssh->state->compression_in_stream.avail_out)) != 0)
797 * Comments in zlib.h say that we should keep calling
798 * inflate() until we get an error. This appears to
799 * be the error that we get.
803 return SSH_ERR_INVALID_FORMAT;
805 return SSH_ERR_ALLOC_FAIL;
808 ssh->state->compression_in_failures++;
809 return SSH_ERR_INTERNAL_ERROR;
816 ssh_clear_newkeys(struct ssh *ssh, int mode)
818 if (ssh->kex && ssh->kex->newkeys[mode]) {
819 kex_free_newkeys(ssh->kex->newkeys[mode]);
820 ssh->kex->newkeys[mode] = NULL;
825 ssh_set_newkeys(struct ssh *ssh, int mode)
827 struct session_state *state = ssh->state;
830 struct sshcomp *comp;
831 struct sshcipher_ctx **ccp;
832 struct packet_state *ps;
833 u_int64_t *max_blocks;
837 debug2("set_newkeys: mode %d", mode);
839 if (mode == MODE_OUT) {
840 ccp = &state->send_context;
841 crypt_type = CIPHER_ENCRYPT;
843 max_blocks = &state->max_blocks_out;
845 ccp = &state->receive_context;
846 crypt_type = CIPHER_DECRYPT;
848 max_blocks = &state->max_blocks_in;
850 if (state->newkeys[mode] != NULL) {
851 debug("set_newkeys: rekeying, input %llu bytes %llu blocks, "
852 "output %llu bytes %llu blocks",
853 (unsigned long long)state->p_read.bytes,
854 (unsigned long long)state->p_read.blocks,
855 (unsigned long long)state->p_send.bytes,
856 (unsigned long long)state->p_send.blocks);
859 kex_free_newkeys(state->newkeys[mode]);
860 state->newkeys[mode] = NULL;
862 /* note that both bytes and the seqnr are not reset */
863 ps->packets = ps->blocks = 0;
864 /* move newkeys from kex to state */
865 if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
866 return SSH_ERR_INTERNAL_ERROR;
867 ssh->kex->newkeys[mode] = NULL;
868 enc = &state->newkeys[mode]->enc;
869 mac = &state->newkeys[mode]->mac;
870 comp = &state->newkeys[mode]->comp;
871 if (cipher_authlen(enc->cipher) == 0) {
872 if ((r = mac_init(mac)) != 0)
876 DBG(debug("cipher_init_context: %d", mode));
877 if ((r = cipher_init(ccp, enc->cipher, enc->key, enc->key_len,
878 enc->iv, enc->iv_len, crypt_type)) != 0)
880 if (!state->cipher_warning_done &&
881 (wmsg = cipher_warning_message(*ccp)) != NULL) {
882 error("Warning: %s", wmsg);
883 state->cipher_warning_done = 1;
885 /* Deleting the keys does not gain extra security */
886 /* explicit_bzero(enc->iv, enc->block_size);
887 explicit_bzero(enc->key, enc->key_len);
888 explicit_bzero(mac->key, mac->key_len); */
889 if ((comp->type == COMP_ZLIB ||
890 (comp->type == COMP_DELAYED &&
891 state->after_authentication)) && comp->enabled == 0) {
892 if ((r = ssh_packet_init_compression(ssh)) < 0)
894 if (mode == MODE_OUT) {
895 if ((r = start_compression_out(ssh, 6)) != 0)
898 if ((r = start_compression_in(ssh)) != 0)
904 * The 2^(blocksize*2) limit is too expensive for 3DES,
905 * so enforce a 1GB limit for small blocksizes.
906 * See RFC4344 section 3.2.
908 if (enc->block_size >= 16)
909 *max_blocks = (u_int64_t)1 << (enc->block_size*2);
911 *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
912 if (state->rekey_limit)
913 *max_blocks = MINIMUM(*max_blocks,
914 state->rekey_limit / enc->block_size);
915 debug("rekey after %llu blocks", (unsigned long long)*max_blocks);
919 #define MAX_PACKETS (1U<<31)
921 ssh_packet_need_rekeying(struct ssh *ssh, u_int outbound_packet_len)
923 struct session_state *state = ssh->state;
924 u_int32_t out_blocks;
926 /* XXX client can't cope with rekeying pre-auth */
927 if (!state->after_authentication)
930 /* Haven't keyed yet or KEX in progress. */
931 if (ssh->kex == NULL || ssh_packet_is_rekeying(ssh))
934 /* Peer can't rekey */
935 if (ssh->compat & SSH_BUG_NOREKEY)
939 * Permit one packet in or out per rekey - this allows us to
940 * make progress when rekey limits are very small.
942 if (state->p_send.packets == 0 && state->p_read.packets == 0)
945 /* Time-based rekeying */
946 if (state->rekey_interval != 0 &&
947 (int64_t)state->rekey_time + state->rekey_interval <= monotime())
951 * Always rekey when MAX_PACKETS sent in either direction
952 * As per RFC4344 section 3.1 we do this after 2^31 packets.
954 if (state->p_send.packets > MAX_PACKETS ||
955 state->p_read.packets > MAX_PACKETS)
958 /* Rekey after (cipher-specific) maxiumum blocks */
959 out_blocks = ROUNDUP(outbound_packet_len,
960 state->newkeys[MODE_OUT]->enc.block_size);
961 return (state->max_blocks_out &&
962 (state->p_send.blocks + out_blocks > state->max_blocks_out)) ||
963 (state->max_blocks_in &&
964 (state->p_read.blocks > state->max_blocks_in));
968 * Delayed compression for SSH2 is enabled after authentication:
969 * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
970 * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
973 ssh_packet_enable_delayed_compress(struct ssh *ssh)
975 struct session_state *state = ssh->state;
976 struct sshcomp *comp = NULL;
980 * Remember that we are past the authentication step, so rekeying
981 * with COMP_DELAYED will turn on compression immediately.
983 state->after_authentication = 1;
984 for (mode = 0; mode < MODE_MAX; mode++) {
985 /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
986 if (state->newkeys[mode] == NULL)
988 comp = &state->newkeys[mode]->comp;
989 if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
990 if ((r = ssh_packet_init_compression(ssh)) != 0)
992 if (mode == MODE_OUT) {
993 if ((r = start_compression_out(ssh, 6)) != 0)
996 if ((r = start_compression_in(ssh)) != 0)
1005 /* Used to mute debug logging for noisy packet types */
1007 ssh_packet_log_type(u_char type)
1010 case SSH2_MSG_CHANNEL_DATA:
1011 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1012 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1020 * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1023 ssh_packet_send2_wrapped(struct ssh *ssh)
1025 struct session_state *state = ssh->state;
1026 u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1027 u_char tmp, padlen, pad = 0;
1028 u_int authlen = 0, aadlen = 0;
1030 struct sshenc *enc = NULL;
1031 struct sshmac *mac = NULL;
1032 struct sshcomp *comp = NULL;
1035 if (state->newkeys[MODE_OUT] != NULL) {
1036 enc = &state->newkeys[MODE_OUT]->enc;
1037 mac = &state->newkeys[MODE_OUT]->mac;
1038 comp = &state->newkeys[MODE_OUT]->comp;
1039 /* disable mac for authenticated encryption */
1040 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1043 block_size = enc ? enc->block_size : 8;
1044 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1046 type = (sshbuf_ptr(state->outgoing_packet))[5];
1047 if (ssh_packet_log_type(type))
1048 debug3("send packet: type %u", type);
1050 fprintf(stderr, "plain: ");
1051 sshbuf_dump(state->outgoing_packet, stderr);
1054 if (comp && comp->enabled) {
1055 len = sshbuf_len(state->outgoing_packet);
1056 /* skip header, compress only payload */
1057 if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1059 sshbuf_reset(state->compression_buffer);
1060 if ((r = compress_buffer(ssh, state->outgoing_packet,
1061 state->compression_buffer)) != 0)
1063 sshbuf_reset(state->outgoing_packet);
1064 if ((r = sshbuf_put(state->outgoing_packet,
1065 "\0\0\0\0\0", 5)) != 0 ||
1066 (r = sshbuf_putb(state->outgoing_packet,
1067 state->compression_buffer)) != 0)
1069 DBG(debug("compression: raw %d compressed %zd", len,
1070 sshbuf_len(state->outgoing_packet)));
1073 /* sizeof (packet_len + pad_len + payload) */
1074 len = sshbuf_len(state->outgoing_packet);
1077 * calc size of padding, alloc space, get random data,
1078 * minimum padding is 4 bytes
1080 len -= aadlen; /* packet length is not encrypted for EtM modes */
1081 padlen = block_size - (len % block_size);
1083 padlen += block_size;
1084 if (state->extra_pad) {
1085 tmp = state->extra_pad;
1087 ROUNDUP(state->extra_pad, block_size);
1088 /* check if roundup overflowed */
1089 if (state->extra_pad < tmp)
1090 return SSH_ERR_INVALID_ARGUMENT;
1091 tmp = (len + padlen) % state->extra_pad;
1092 /* Check whether pad calculation below will underflow */
1093 if (tmp > state->extra_pad)
1094 return SSH_ERR_INVALID_ARGUMENT;
1095 pad = state->extra_pad - tmp;
1096 DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1097 __func__, pad, len, padlen, state->extra_pad));
1100 /* Check whether padlen calculation overflowed */
1102 return SSH_ERR_INVALID_ARGUMENT; /* overflow */
1103 state->extra_pad = 0;
1105 if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1107 if (enc && !cipher_ctx_is_plaintext(state->send_context)) {
1108 /* random padding */
1109 arc4random_buf(cp, padlen);
1112 explicit_bzero(cp, padlen);
1114 /* sizeof (packet_len + pad_len + payload + padding) */
1115 len = sshbuf_len(state->outgoing_packet);
1116 cp = sshbuf_mutable_ptr(state->outgoing_packet);
1118 r = SSH_ERR_INTERNAL_ERROR;
1121 /* packet_length includes payload, padding and padding length field */
1122 POKE_U32(cp, len - 4);
1124 DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1125 len, padlen, aadlen));
1127 /* compute MAC over seqnr and packet(length fields, payload, padding) */
1128 if (mac && mac->enabled && !mac->etm) {
1129 if ((r = mac_compute(mac, state->p_send.seqnr,
1130 sshbuf_ptr(state->outgoing_packet), len,
1131 macbuf, sizeof(macbuf))) != 0)
1133 DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1135 /* encrypt packet and append to output buffer. */
1136 if ((r = sshbuf_reserve(state->output,
1137 sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1139 if ((r = cipher_crypt(state->send_context, state->p_send.seqnr, cp,
1140 sshbuf_ptr(state->outgoing_packet),
1141 len - aadlen, aadlen, authlen)) != 0)
1143 /* append unencrypted MAC */
1144 if (mac && mac->enabled) {
1146 /* EtM: compute mac over aadlen + cipher text */
1147 if ((r = mac_compute(mac, state->p_send.seqnr,
1148 cp, len, macbuf, sizeof(macbuf))) != 0)
1150 DBG(debug("done calc MAC(EtM) out #%d",
1151 state->p_send.seqnr));
1153 if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1157 fprintf(stderr, "encrypted: ");
1158 sshbuf_dump(state->output, stderr);
1160 /* increment sequence number for outgoing packets */
1161 if (++state->p_send.seqnr == 0)
1162 logit("outgoing seqnr wraps around");
1163 if (++state->p_send.packets == 0)
1164 if (!(ssh->compat & SSH_BUG_NOREKEY))
1165 return SSH_ERR_NEED_REKEY;
1166 state->p_send.blocks += len / block_size;
1167 state->p_send.bytes += len;
1168 sshbuf_reset(state->outgoing_packet);
1170 if (type == SSH2_MSG_NEWKEYS)
1171 r = ssh_set_newkeys(ssh, MODE_OUT);
1172 else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1173 r = ssh_packet_enable_delayed_compress(ssh);
1180 /* returns non-zero if the specified packet type is usec by KEX */
1182 ssh_packet_type_is_kex(u_char type)
1185 type >= SSH2_MSG_TRANSPORT_MIN &&
1186 type <= SSH2_MSG_TRANSPORT_MAX &&
1187 type != SSH2_MSG_SERVICE_REQUEST &&
1188 type != SSH2_MSG_SERVICE_ACCEPT &&
1189 type != SSH2_MSG_EXT_INFO;
1193 ssh_packet_send2(struct ssh *ssh)
1195 struct session_state *state = ssh->state;
1200 if (sshbuf_len(state->outgoing_packet) < 6)
1201 return SSH_ERR_INTERNAL_ERROR;
1202 type = sshbuf_ptr(state->outgoing_packet)[5];
1203 need_rekey = !ssh_packet_type_is_kex(type) &&
1204 ssh_packet_need_rekeying(ssh, sshbuf_len(state->outgoing_packet));
1207 * During rekeying we can only send key exchange messages.
1208 * Queue everything else.
1210 if ((need_rekey || state->rekeying) && !ssh_packet_type_is_kex(type)) {
1212 debug3("%s: rekex triggered", __func__);
1213 debug("enqueue packet: %u", type);
1214 p = calloc(1, sizeof(*p));
1216 return SSH_ERR_ALLOC_FAIL;
1218 p->payload = state->outgoing_packet;
1219 TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1220 state->outgoing_packet = sshbuf_new();
1221 if (state->outgoing_packet == NULL)
1222 return SSH_ERR_ALLOC_FAIL;
1225 * This packet triggered a rekey, so send the
1227 * NB. reenters this function via kex_start_rekex().
1229 return kex_start_rekex(ssh);
1234 /* rekeying starts with sending KEXINIT */
1235 if (type == SSH2_MSG_KEXINIT)
1236 state->rekeying = 1;
1238 if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1241 /* after a NEWKEYS message we can send the complete queue */
1242 if (type == SSH2_MSG_NEWKEYS) {
1243 state->rekeying = 0;
1244 state->rekey_time = monotime();
1245 while ((p = TAILQ_FIRST(&state->outgoing))) {
1248 * If this packet triggers a rekex, then skip the
1249 * remaining packets in the queue for now.
1250 * NB. re-enters this function via kex_start_rekex.
1252 if (ssh_packet_need_rekeying(ssh,
1253 sshbuf_len(p->payload))) {
1254 debug3("%s: queued packet triggered rekex",
1256 return kex_start_rekex(ssh);
1258 debug("dequeue packet: %u", type);
1259 sshbuf_free(state->outgoing_packet);
1260 state->outgoing_packet = p->payload;
1261 TAILQ_REMOVE(&state->outgoing, p, next);
1262 memset(p, 0, sizeof(*p));
1264 if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1272 * Waits until a packet has been received, and returns its type. Note that
1273 * no other data is processed until this returns, so this function should not
1274 * be used during the interactive session.
1278 ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1280 struct session_state *state = ssh->state;
1281 int len, r, ms_remain;
1284 struct timeval timeout, start, *timeoutp = NULL;
1286 DBG(debug("packet_read()"));
1288 setp = calloc(howmany(state->connection_in + 1,
1289 NFDBITS), sizeof(fd_mask));
1291 return SSH_ERR_ALLOC_FAIL;
1294 * Since we are blocking, ensure that all written packets have
1297 if ((r = ssh_packet_write_wait(ssh)) != 0)
1300 /* Stay in the loop until we have received a complete packet. */
1302 /* Try to read a packet from the buffer. */
1303 r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1306 /* If we got a packet, return it. */
1307 if (*typep != SSH_MSG_NONE)
1310 * Otherwise, wait for some data to arrive, add it to the
1311 * buffer, and try again.
1313 memset(setp, 0, howmany(state->connection_in + 1,
1314 NFDBITS) * sizeof(fd_mask));
1315 FD_SET(state->connection_in, setp);
1317 if (state->packet_timeout_ms > 0) {
1318 ms_remain = state->packet_timeout_ms;
1319 timeoutp = &timeout;
1321 /* Wait for some data to arrive. */
1323 if (state->packet_timeout_ms != -1) {
1324 ms_to_timeval(&timeout, ms_remain);
1325 gettimeofday(&start, NULL);
1327 if ((r = select(state->connection_in + 1, setp,
1328 NULL, NULL, timeoutp)) >= 0)
1330 if (errno != EAGAIN && errno != EINTR &&
1331 errno != EWOULDBLOCK)
1333 if (state->packet_timeout_ms == -1)
1335 ms_subtract_diff(&start, &ms_remain);
1336 if (ms_remain <= 0) {
1342 r = SSH_ERR_CONN_TIMEOUT;
1345 /* Read data from the socket. */
1346 len = read(state->connection_in, buf, sizeof(buf));
1348 r = SSH_ERR_CONN_CLOSED;
1352 r = SSH_ERR_SYSTEM_ERROR;
1356 /* Append it to the buffer. */
1357 if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1366 ssh_packet_read(struct ssh *ssh)
1371 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1372 fatal("%s: %s", __func__, ssh_err(r));
1377 * Waits until a packet has been received, verifies that its type matches
1378 * that given, and gives a fatal error and exits if there is a mismatch.
1382 ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1387 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1389 if (type != expected_type) {
1390 if ((r = sshpkt_disconnect(ssh,
1391 "Protocol error: expected packet type %d, got %d",
1392 expected_type, type)) != 0)
1394 return SSH_ERR_PROTOCOL_ERROR;
1400 ssh_packet_read_poll2_mux(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1402 struct session_state *state = ssh->state;
1408 return SSH_ERR_INTERNAL_ERROR;
1409 *typep = SSH_MSG_NONE;
1410 cp = sshbuf_ptr(state->input);
1411 if (state->packlen == 0) {
1412 if (sshbuf_len(state->input) < 4 + 1)
1413 return 0; /* packet is incomplete */
1414 state->packlen = PEEK_U32(cp);
1415 if (state->packlen < 4 + 1 ||
1416 state->packlen > PACKET_MAX_SIZE)
1417 return SSH_ERR_MESSAGE_INCOMPLETE;
1419 need = state->packlen + 4;
1420 if (sshbuf_len(state->input) < need)
1421 return 0; /* packet is incomplete */
1422 sshbuf_reset(state->incoming_packet);
1423 if ((r = sshbuf_put(state->incoming_packet, cp + 4,
1424 state->packlen)) != 0 ||
1425 (r = sshbuf_consume(state->input, need)) != 0 ||
1426 (r = sshbuf_get_u8(state->incoming_packet, NULL)) != 0 ||
1427 (r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1429 if (ssh_packet_log_type(*typep))
1430 debug3("%s: type %u", __func__, *typep);
1431 /* sshbuf_dump(state->incoming_packet, stderr); */
1432 /* reset for next packet */
1438 ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1440 struct session_state *state = ssh->state;
1443 u_int maclen, aadlen = 0, authlen = 0, block_size;
1444 struct sshenc *enc = NULL;
1445 struct sshmac *mac = NULL;
1446 struct sshcomp *comp = NULL;
1450 return ssh_packet_read_poll2_mux(ssh, typep, seqnr_p);
1452 *typep = SSH_MSG_NONE;
1454 if (state->packet_discard)
1457 if (state->newkeys[MODE_IN] != NULL) {
1458 enc = &state->newkeys[MODE_IN]->enc;
1459 mac = &state->newkeys[MODE_IN]->mac;
1460 comp = &state->newkeys[MODE_IN]->comp;
1461 /* disable mac for authenticated encryption */
1462 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1465 maclen = mac && mac->enabled ? mac->mac_len : 0;
1466 block_size = enc ? enc->block_size : 8;
1467 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1469 if (aadlen && state->packlen == 0) {
1470 if (cipher_get_length(state->receive_context,
1471 &state->packlen, state->p_read.seqnr,
1472 sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1474 if (state->packlen < 1 + 4 ||
1475 state->packlen > PACKET_MAX_SIZE) {
1477 sshbuf_dump(state->input, stderr);
1479 logit("Bad packet length %u.", state->packlen);
1480 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1482 return SSH_ERR_CONN_CORRUPT;
1484 sshbuf_reset(state->incoming_packet);
1485 } else if (state->packlen == 0) {
1487 * check if input size is less than the cipher block size,
1488 * decrypt first block and extract length of incoming packet
1490 if (sshbuf_len(state->input) < block_size)
1492 sshbuf_reset(state->incoming_packet);
1493 if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1496 if ((r = cipher_crypt(state->receive_context,
1497 state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1498 block_size, 0, 0)) != 0)
1500 state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1501 if (state->packlen < 1 + 4 ||
1502 state->packlen > PACKET_MAX_SIZE) {
1504 fprintf(stderr, "input: \n");
1505 sshbuf_dump(state->input, stderr);
1506 fprintf(stderr, "incoming_packet: \n");
1507 sshbuf_dump(state->incoming_packet, stderr);
1509 logit("Bad packet length %u.", state->packlen);
1510 return ssh_packet_start_discard(ssh, enc, mac, 0,
1513 if ((r = sshbuf_consume(state->input, block_size)) != 0)
1516 DBG(debug("input: packet len %u", state->packlen+4));
1519 /* only the payload is encrypted */
1520 need = state->packlen;
1523 * the payload size and the payload are encrypted, but we
1524 * have a partial packet of block_size bytes
1526 need = 4 + state->packlen - block_size;
1528 DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1529 " aadlen %d", block_size, need, maclen, authlen, aadlen));
1530 if (need % block_size != 0) {
1531 logit("padding error: need %d block %d mod %d",
1532 need, block_size, need % block_size);
1533 return ssh_packet_start_discard(ssh, enc, mac, 0,
1534 PACKET_MAX_SIZE - block_size);
1537 * check if the entire packet has been received and
1538 * decrypt into incoming_packet:
1539 * 'aadlen' bytes are unencrypted, but authenticated.
1540 * 'need' bytes are encrypted, followed by either
1541 * 'authlen' bytes of authentication tag or
1542 * 'maclen' bytes of message authentication code.
1544 if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1545 return 0; /* packet is incomplete */
1547 fprintf(stderr, "read_poll enc/full: ");
1548 sshbuf_dump(state->input, stderr);
1550 /* EtM: check mac over encrypted input */
1551 if (mac && mac->enabled && mac->etm) {
1552 if ((r = mac_check(mac, state->p_read.seqnr,
1553 sshbuf_ptr(state->input), aadlen + need,
1554 sshbuf_ptr(state->input) + aadlen + need + authlen,
1556 if (r == SSH_ERR_MAC_INVALID)
1557 logit("Corrupted MAC on input.");
1561 if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1564 if ((r = cipher_crypt(state->receive_context, state->p_read.seqnr, cp,
1565 sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1567 if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1569 if (mac && mac->enabled) {
1570 /* Not EtM: check MAC over cleartext */
1571 if (!mac->etm && (r = mac_check(mac, state->p_read.seqnr,
1572 sshbuf_ptr(state->incoming_packet),
1573 sshbuf_len(state->incoming_packet),
1574 sshbuf_ptr(state->input), maclen)) != 0) {
1575 if (r != SSH_ERR_MAC_INVALID)
1577 logit("Corrupted MAC on input.");
1578 if (need + block_size > PACKET_MAX_SIZE)
1579 return SSH_ERR_INTERNAL_ERROR;
1580 return ssh_packet_start_discard(ssh, enc, mac,
1581 sshbuf_len(state->incoming_packet),
1582 PACKET_MAX_SIZE - need - block_size);
1584 /* Remove MAC from input buffer */
1585 DBG(debug("MAC #%d ok", state->p_read.seqnr));
1586 if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1589 if (seqnr_p != NULL)
1590 *seqnr_p = state->p_read.seqnr;
1591 if (++state->p_read.seqnr == 0)
1592 logit("incoming seqnr wraps around");
1593 if (++state->p_read.packets == 0)
1594 if (!(ssh->compat & SSH_BUG_NOREKEY))
1595 return SSH_ERR_NEED_REKEY;
1596 state->p_read.blocks += (state->packlen + 4) / block_size;
1597 state->p_read.bytes += state->packlen + 4;
1600 padlen = sshbuf_ptr(state->incoming_packet)[4];
1601 DBG(debug("input: padlen %d", padlen));
1603 if ((r = sshpkt_disconnect(ssh,
1604 "Corrupted padlen %d on input.", padlen)) != 0 ||
1605 (r = ssh_packet_write_wait(ssh)) != 0)
1607 return SSH_ERR_CONN_CORRUPT;
1610 /* skip packet size + padlen, discard padding */
1611 if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1612 ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1615 DBG(debug("input: len before de-compress %zd",
1616 sshbuf_len(state->incoming_packet)));
1617 if (comp && comp->enabled) {
1618 sshbuf_reset(state->compression_buffer);
1619 if ((r = uncompress_buffer(ssh, state->incoming_packet,
1620 state->compression_buffer)) != 0)
1622 sshbuf_reset(state->incoming_packet);
1623 if ((r = sshbuf_putb(state->incoming_packet,
1624 state->compression_buffer)) != 0)
1626 DBG(debug("input: len after de-compress %zd",
1627 sshbuf_len(state->incoming_packet)));
1630 * get packet type, implies consume.
1631 * return length of payload (without type field)
1633 if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1635 if (ssh_packet_log_type(*typep))
1636 debug3("receive packet: type %u", *typep);
1637 if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1638 if ((r = sshpkt_disconnect(ssh,
1639 "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1640 (r = ssh_packet_write_wait(ssh)) != 0)
1642 return SSH_ERR_PROTOCOL_ERROR;
1644 if (state->hook_in != NULL &&
1645 (r = state->hook_in(ssh, state->incoming_packet, typep,
1646 state->hook_in_ctx)) != 0)
1648 if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1649 r = ssh_packet_enable_delayed_compress(ssh);
1653 fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1654 sshbuf_dump(state->incoming_packet, stderr);
1656 /* reset for next packet */
1659 /* do we need to rekey? */
1660 if (ssh_packet_need_rekeying(ssh, 0)) {
1661 debug3("%s: rekex triggered", __func__);
1662 if ((r = kex_start_rekex(ssh)) != 0)
1670 ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1672 struct session_state *state = ssh->state;
1673 u_int reason, seqnr;
1679 r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1683 state->keep_alive_timeouts = 0;
1684 DBG(debug("received packet type %d", *typep));
1687 case SSH2_MSG_IGNORE:
1688 debug3("Received SSH2_MSG_IGNORE");
1690 case SSH2_MSG_DEBUG:
1691 if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1692 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1693 (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1697 debug("Remote: %.900s", msg);
1700 case SSH2_MSG_DISCONNECT:
1701 if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1702 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1704 /* Ignore normal client exit notifications */
1705 do_log2(ssh->state->server_side &&
1706 reason == SSH2_DISCONNECT_BY_APPLICATION ?
1707 SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1708 "Received disconnect from %s port %d:"
1709 "%u: %.400s", ssh_remote_ipaddr(ssh),
1710 ssh_remote_port(ssh), reason, msg);
1712 return SSH_ERR_DISCONNECTED;
1713 case SSH2_MSG_UNIMPLEMENTED:
1714 if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1716 debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1726 * Buffers the given amount of input characters. This is intended to be used
1727 * together with packet_read_poll.
1731 ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1733 struct session_state *state = ssh->state;
1736 if (state->packet_discard) {
1737 state->keep_alive_timeouts = 0; /* ?? */
1738 if (len >= state->packet_discard) {
1739 if ((r = ssh_packet_stop_discard(ssh)) != 0)
1742 state->packet_discard -= len;
1745 if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1752 ssh_packet_remaining(struct ssh *ssh)
1754 return sshbuf_len(ssh->state->incoming_packet);
1758 * Sends a diagnostic message from the server to the client. This message
1759 * can be sent at any time (but not while constructing another message). The
1760 * message is printed immediately, but only if the client is being executed
1761 * in verbose mode. These messages are primarily intended to ease debugging
1762 * authentication problems. The length of the formatted message must not
1763 * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1766 ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1772 if ((ssh->compat & SSH_BUG_DEBUG))
1775 va_start(args, fmt);
1776 vsnprintf(buf, sizeof(buf), fmt, args);
1779 if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1780 (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1781 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1782 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1783 (r = sshpkt_send(ssh)) != 0 ||
1784 (r = ssh_packet_write_wait(ssh)) != 0)
1785 fatal("%s: %s", __func__, ssh_err(r));
1789 fmt_connection_id(struct ssh *ssh, char *s, size_t l)
1791 snprintf(s, l, "%.200s%s%s port %d",
1792 ssh->log_preamble ? ssh->log_preamble : "",
1793 ssh->log_preamble ? " " : "",
1794 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1798 * Pretty-print connection-terminating errors and exit.
1801 sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1803 char remote_id[512];
1805 fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1808 case SSH_ERR_CONN_CLOSED:
1809 ssh_packet_clear_keys(ssh);
1810 logdie("Connection closed by %s", remote_id);
1811 case SSH_ERR_CONN_TIMEOUT:
1812 ssh_packet_clear_keys(ssh);
1813 logdie("Connection %s %s timed out",
1814 ssh->state->server_side ? "from" : "to", remote_id);
1815 case SSH_ERR_DISCONNECTED:
1816 ssh_packet_clear_keys(ssh);
1817 logdie("Disconnected from %s", remote_id);
1818 case SSH_ERR_SYSTEM_ERROR:
1819 if (errno == ECONNRESET) {
1820 ssh_packet_clear_keys(ssh);
1821 logdie("Connection reset by %s", remote_id);
1824 case SSH_ERR_NO_CIPHER_ALG_MATCH:
1825 case SSH_ERR_NO_MAC_ALG_MATCH:
1826 case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1827 case SSH_ERR_NO_KEX_ALG_MATCH:
1828 case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1829 if (ssh && ssh->kex && ssh->kex->failed_choice) {
1830 BLACKLIST_NOTIFY(BLACKLIST_AUTH_FAIL, "ssh");
1831 ssh_packet_clear_keys(ssh);
1832 logdie("Unable to negotiate with %s: %s. "
1833 "Their offer: %s", remote_id, ssh_err(r),
1834 ssh->kex->failed_choice);
1838 ssh_packet_clear_keys(ssh);
1839 logdie("%s%sConnection %s %s: %s",
1840 tag != NULL ? tag : "", tag != NULL ? ": " : "",
1841 ssh->state->server_side ? "from" : "to",
1842 remote_id, ssh_err(r));
1847 * Logs the error plus constructs and sends a disconnect packet, closes the
1848 * connection, and exits. This function never returns. The error message
1849 * should not contain a newline. The length of the formatted message must
1850 * not exceed 1024 bytes.
1853 ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1855 char buf[1024], remote_id[512];
1857 static int disconnecting = 0;
1860 if (disconnecting) /* Guard against recursive invocations. */
1861 fatal("packet_disconnect called recursively.");
1865 * Format the message. Note that the caller must make sure the
1866 * message is of limited size.
1868 fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1869 va_start(args, fmt);
1870 vsnprintf(buf, sizeof(buf), fmt, args);
1873 /* Display the error locally */
1874 logit("Disconnecting %s: %.100s", remote_id, buf);
1877 * Send the disconnect message to the other side, and wait
1878 * for it to get sent.
1880 if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1881 sshpkt_fatal(ssh, __func__, r);
1883 if ((r = ssh_packet_write_wait(ssh)) != 0)
1884 sshpkt_fatal(ssh, __func__, r);
1886 /* Close the connection. */
1887 ssh_packet_close(ssh);
1892 * Checks if there is any buffered output, and tries to write some of
1896 ssh_packet_write_poll(struct ssh *ssh)
1898 struct session_state *state = ssh->state;
1899 int len = sshbuf_len(state->output);
1903 len = write(state->connection_out,
1904 sshbuf_ptr(state->output), len);
1906 if (errno == EINTR || errno == EAGAIN ||
1907 errno == EWOULDBLOCK)
1909 return SSH_ERR_SYSTEM_ERROR;
1912 return SSH_ERR_CONN_CLOSED;
1913 if ((r = sshbuf_consume(state->output, len)) != 0)
1920 * Calls packet_write_poll repeatedly until all pending output data has been
1924 ssh_packet_write_wait(struct ssh *ssh)
1927 int ret, r, ms_remain = 0;
1928 struct timeval start, timeout, *timeoutp = NULL;
1929 struct session_state *state = ssh->state;
1931 setp = calloc(howmany(state->connection_out + 1,
1932 NFDBITS), sizeof(fd_mask));
1934 return SSH_ERR_ALLOC_FAIL;
1935 if ((r = ssh_packet_write_poll(ssh)) != 0) {
1939 while (ssh_packet_have_data_to_write(ssh)) {
1940 memset(setp, 0, howmany(state->connection_out + 1,
1941 NFDBITS) * sizeof(fd_mask));
1942 FD_SET(state->connection_out, setp);
1944 if (state->packet_timeout_ms > 0) {
1945 ms_remain = state->packet_timeout_ms;
1946 timeoutp = &timeout;
1949 if (state->packet_timeout_ms != -1) {
1950 ms_to_timeval(&timeout, ms_remain);
1951 gettimeofday(&start, NULL);
1953 if ((ret = select(state->connection_out + 1,
1954 NULL, setp, NULL, timeoutp)) >= 0)
1956 if (errno != EAGAIN && errno != EINTR &&
1957 errno != EWOULDBLOCK)
1959 if (state->packet_timeout_ms == -1)
1961 ms_subtract_diff(&start, &ms_remain);
1962 if (ms_remain <= 0) {
1969 return SSH_ERR_CONN_TIMEOUT;
1971 if ((r = ssh_packet_write_poll(ssh)) != 0) {
1980 /* Returns true if there is buffered data to write to the connection. */
1983 ssh_packet_have_data_to_write(struct ssh *ssh)
1985 return sshbuf_len(ssh->state->output) != 0;
1988 /* Returns true if there is not too much data to write to the connection. */
1991 ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1993 if (ssh->state->interactive_mode)
1994 return sshbuf_len(ssh->state->output) < 16384;
1996 return sshbuf_len(ssh->state->output) < 128 * 1024;
2000 ssh_packet_set_tos(struct ssh *ssh, int tos)
2002 #ifndef IP_TOS_IS_BROKEN
2003 if (!ssh_packet_connection_is_on_socket(ssh) || tos == INT_MAX)
2005 switch (ssh_packet_connection_af(ssh)) {
2008 debug3("%s: set IP_TOS 0x%02x", __func__, tos);
2009 if (setsockopt(ssh->state->connection_in,
2010 IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2011 error("setsockopt IP_TOS %d: %.100s:",
2012 tos, strerror(errno));
2014 # endif /* IP_TOS */
2017 debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
2018 if (setsockopt(ssh->state->connection_in,
2019 IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2020 error("setsockopt IPV6_TCLASS %d: %.100s:",
2021 tos, strerror(errno));
2023 # endif /* IPV6_TCLASS */
2025 #endif /* IP_TOS_IS_BROKEN */
2028 /* Informs that the current session is interactive. Sets IP flags for that. */
2031 ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
2033 struct session_state *state = ssh->state;
2035 if (state->set_interactive_called)
2037 state->set_interactive_called = 1;
2039 /* Record that we are in interactive mode. */
2040 state->interactive_mode = interactive;
2042 /* Only set socket options if using a socket. */
2043 if (!ssh_packet_connection_is_on_socket(ssh))
2045 set_nodelay(state->connection_in);
2046 ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2050 /* Returns true if the current connection is interactive. */
2053 ssh_packet_is_interactive(struct ssh *ssh)
2055 return ssh->state->interactive_mode;
2059 ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
2061 struct session_state *state = ssh->state;
2063 if (state->set_maxsize_called) {
2064 logit("packet_set_maxsize: called twice: old %d new %d",
2065 state->max_packet_size, s);
2068 if (s < 4 * 1024 || s > 1024 * 1024) {
2069 logit("packet_set_maxsize: bad size %d", s);
2072 state->set_maxsize_called = 1;
2073 debug("packet_set_maxsize: setting to %d", s);
2074 state->max_packet_size = s;
2079 ssh_packet_inc_alive_timeouts(struct ssh *ssh)
2081 return ++ssh->state->keep_alive_timeouts;
2085 ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
2087 ssh->state->keep_alive_timeouts = ka;
2091 ssh_packet_get_maxsize(struct ssh *ssh)
2093 return ssh->state->max_packet_size;
2097 ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, u_int32_t seconds)
2099 debug3("rekey after %llu bytes, %u seconds", (unsigned long long)bytes,
2100 (unsigned int)seconds);
2101 ssh->state->rekey_limit = bytes;
2102 ssh->state->rekey_interval = seconds;
2106 ssh_packet_get_rekey_timeout(struct ssh *ssh)
2110 seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
2112 return (seconds <= 0 ? 1 : seconds);
2116 ssh_packet_set_server(struct ssh *ssh)
2118 ssh->state->server_side = 1;
2122 ssh_packet_set_authenticated(struct ssh *ssh)
2124 ssh->state->after_authentication = 1;
2128 ssh_packet_get_input(struct ssh *ssh)
2130 return (void *)ssh->state->input;
2134 ssh_packet_get_output(struct ssh *ssh)
2136 return (void *)ssh->state->output;
2139 /* Reset after_authentication and reset compression in post-auth privsep */
2141 ssh_packet_set_postauth(struct ssh *ssh)
2145 debug("%s: called", __func__);
2146 /* This was set in net child, but is not visible in user child */
2147 ssh->state->after_authentication = 1;
2148 ssh->state->rekeying = 0;
2149 if ((r = ssh_packet_enable_delayed_compress(ssh)) != 0)
2154 /* Packet state (de-)serialization for privsep */
2156 /* turn kex into a blob for packet state serialization */
2158 kex_to_blob(struct sshbuf *m, struct kex *kex)
2162 if ((r = sshbuf_put_string(m, kex->session_id,
2163 kex->session_id_len)) != 0 ||
2164 (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2165 (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2166 (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2167 (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2168 (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2169 (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2170 (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2171 (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2176 /* turn key exchange results into a blob for packet state serialization */
2178 newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2181 struct sshcipher_ctx *cc;
2182 struct sshcomp *comp;
2185 struct newkeys *newkey;
2188 if ((newkey = ssh->state->newkeys[mode]) == NULL)
2189 return SSH_ERR_INTERNAL_ERROR;
2192 comp = &newkey->comp;
2193 cc = (mode == MODE_OUT) ? ssh->state->send_context :
2194 ssh->state->receive_context;
2195 if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2197 if ((b = sshbuf_new()) == NULL)
2198 return SSH_ERR_ALLOC_FAIL;
2199 if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2200 (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2201 (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2202 (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2203 (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2205 if (cipher_authlen(enc->cipher) == 0) {
2206 if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2207 (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2208 (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2211 if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2212 (r = sshbuf_put_cstring(b, comp->name)) != 0)
2214 r = sshbuf_put_stringb(m, b);
2220 /* serialize packet state into a blob */
2222 ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2224 struct session_state *state = ssh->state;
2227 if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2228 (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2229 (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
2230 (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
2231 (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
2232 (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2233 (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2234 (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2235 (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2236 (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2237 (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2238 (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2239 (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0 ||
2240 (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2241 (r = sshbuf_put_stringb(m, state->output)) != 0)
2247 /* restore key exchange results from blob for packet state de-serialization */
2249 newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2251 struct sshbuf *b = NULL;
2252 struct sshcomp *comp;
2255 struct newkeys *newkey = NULL;
2256 size_t keylen, ivlen, maclen;
2259 if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2260 r = SSH_ERR_ALLOC_FAIL;
2263 if ((r = sshbuf_froms(m, &b)) != 0)
2266 sshbuf_dump(b, stderr);
2270 comp = &newkey->comp;
2272 if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2273 (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2274 (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2275 (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2276 (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2278 if ((enc->cipher = cipher_by_name(enc->name)) == NULL) {
2279 r = SSH_ERR_INVALID_FORMAT;
2282 if (cipher_authlen(enc->cipher) == 0) {
2283 if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2285 if ((r = mac_setup(mac, mac->name)) != 0)
2287 if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2288 (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2290 if (maclen > mac->key_len) {
2291 r = SSH_ERR_INVALID_FORMAT;
2294 mac->key_len = maclen;
2296 if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2297 (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2299 if (sshbuf_len(b) != 0) {
2300 r = SSH_ERR_INVALID_FORMAT;
2303 enc->key_len = keylen;
2304 enc->iv_len = ivlen;
2305 ssh->kex->newkeys[mode] = newkey;
2314 /* restore kex from blob for packet state de-serialization */
2316 kex_from_blob(struct sshbuf *m, struct kex **kexp)
2321 if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2322 (kex->my = sshbuf_new()) == NULL ||
2323 (kex->peer = sshbuf_new()) == NULL) {
2324 r = SSH_ERR_ALLOC_FAIL;
2327 if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2328 (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2329 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2330 (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2331 (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2332 (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2333 (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2334 (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2335 (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2341 if (r != 0 || kexp == NULL) {
2343 sshbuf_free(kex->my);
2344 sshbuf_free(kex->peer);
2356 * Restore packet state from content of blob 'm' (de-serialization).
2357 * Note that 'm' will be partially consumed on parsing or any other errors.
2360 ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2362 struct session_state *state = ssh->state;
2363 const u_char *input, *output;
2367 if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2368 (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2369 (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
2370 (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
2371 (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
2372 (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2373 (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2374 (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2375 (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2376 (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2377 (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2378 (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2379 (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2382 * We set the time here so that in post-auth privsep slave we
2383 * count from the completion of the authentication.
2385 state->rekey_time = monotime();
2386 /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2387 if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2388 (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2391 if ((r = ssh_packet_set_postauth(ssh)) != 0)
2394 sshbuf_reset(state->input);
2395 sshbuf_reset(state->output);
2396 if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2397 (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2398 (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2399 (r = sshbuf_put(state->output, output, olen)) != 0)
2403 return SSH_ERR_INVALID_FORMAT;
2404 debug3("%s: done", __func__);
2410 /* put data to the outgoing packet */
2413 sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2415 return sshbuf_put(ssh->state->outgoing_packet, v, len);
2419 sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2421 return sshbuf_putb(ssh->state->outgoing_packet, b);
2425 sshpkt_put_u8(struct ssh *ssh, u_char val)
2427 return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2431 sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2433 return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2437 sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2439 return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2443 sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2445 return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2449 sshpkt_put_cstring(struct ssh *ssh, const void *v)
2451 return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2455 sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2457 return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2461 #ifdef OPENSSL_HAS_ECC
2463 sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2465 return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2467 #endif /* OPENSSL_HAS_ECC */
2471 sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2473 return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2475 #endif /* WITH_OPENSSL */
2477 /* fetch data from the incoming packet */
2480 sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2482 return sshbuf_get(ssh->state->incoming_packet, valp, len);
2486 sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2488 return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2492 sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2494 return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2498 sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2500 return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2504 sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2506 return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2510 sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2512 return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2516 sshpkt_peek_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2518 return sshbuf_peek_string_direct(ssh->state->incoming_packet, valp, lenp);
2522 sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2524 return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2528 #ifdef OPENSSL_HAS_ECC
2530 sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2532 return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2534 #endif /* OPENSSL_HAS_ECC */
2538 sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2540 return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2542 #endif /* WITH_OPENSSL */
2545 sshpkt_get_end(struct ssh *ssh)
2547 if (sshbuf_len(ssh->state->incoming_packet) > 0)
2548 return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2553 sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2556 *lenp = sshbuf_len(ssh->state->incoming_packet);
2557 return sshbuf_ptr(ssh->state->incoming_packet);
2560 /* start a new packet */
2563 sshpkt_start(struct ssh *ssh, u_char type)
2565 u_char buf[6]; /* u32 packet length, u8 pad len, u8 type */
2567 DBG(debug("packet_start[%d]", type));
2568 memset(buf, 0, sizeof(buf));
2569 buf[sizeof(buf) - 1] = type;
2570 sshbuf_reset(ssh->state->outgoing_packet);
2571 return sshbuf_put(ssh->state->outgoing_packet, buf, sizeof(buf));
2575 ssh_packet_send_mux(struct ssh *ssh)
2577 struct session_state *state = ssh->state;
2583 return SSH_ERR_INTERNAL_ERROR;
2584 len = sshbuf_len(state->outgoing_packet);
2586 return SSH_ERR_INTERNAL_ERROR;
2587 cp = sshbuf_mutable_ptr(state->outgoing_packet);
2589 if (ssh_packet_log_type(type))
2590 debug3("%s: type %u", __func__, type);
2591 /* drop everything, but the connection protocol */
2592 if (type >= SSH2_MSG_CONNECTION_MIN &&
2593 type <= SSH2_MSG_CONNECTION_MAX) {
2594 POKE_U32(cp, len - 4);
2595 if ((r = sshbuf_putb(state->output,
2596 state->outgoing_packet)) != 0)
2598 /* sshbuf_dump(state->output, stderr); */
2600 sshbuf_reset(state->outgoing_packet);
2605 * 9.2. Ignored Data Message
2607 * byte SSH_MSG_IGNORE
2610 * All implementations MUST understand (and ignore) this message at any
2611 * time (after receiving the protocol version). No implementation is
2612 * required to send them. This message can be used as an additional
2613 * protection measure against advanced traffic analysis techniques.
2616 sshpkt_msg_ignore(struct ssh *ssh, u_int nbytes)
2622 if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
2623 (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2625 for (i = 0; i < nbytes; i++) {
2628 if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2638 sshpkt_send(struct ssh *ssh)
2640 if (ssh->state && ssh->state->mux)
2641 return ssh_packet_send_mux(ssh);
2642 return ssh_packet_send2(ssh);
2646 sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2652 va_start(args, fmt);
2653 vsnprintf(buf, sizeof(buf), fmt, args);
2656 if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2657 (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2658 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2659 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2660 (r = sshpkt_send(ssh)) != 0)
2665 /* roundup current message to pad bytes */
2667 sshpkt_add_padding(struct ssh *ssh, u_char pad)
2669 ssh->state->extra_pad = pad;