1 /* $OpenBSD: packet.c,v 1.269 2017/12/18 23:13:42 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 /* Returns the routing domain of the input socket, or NULL if unavailable */
564 ssh_packet_rdomain_in(struct ssh *ssh)
566 if (ssh->rdomain_in != NULL)
567 return ssh->rdomain_in;
568 if (!ssh_packet_connection_is_on_socket(ssh))
570 ssh->rdomain_in = get_rdomain(ssh->state->connection_in);
571 return ssh->rdomain_in;
574 /* Closes the connection and clears and frees internal data structures. */
577 ssh_packet_close_internal(struct ssh *ssh, int do_close)
579 struct session_state *state = ssh->state;
582 if (!state->initialized)
584 state->initialized = 0;
586 if (state->connection_in == state->connection_out) {
587 close(state->connection_out);
589 close(state->connection_in);
590 close(state->connection_out);
593 sshbuf_free(state->input);
594 sshbuf_free(state->output);
595 sshbuf_free(state->outgoing_packet);
596 sshbuf_free(state->incoming_packet);
597 for (mode = 0; mode < MODE_MAX; mode++) {
598 kex_free_newkeys(state->newkeys[mode]); /* current keys */
599 state->newkeys[mode] = NULL;
600 ssh_clear_newkeys(ssh, mode); /* next keys */
602 /* comression state is in shared mem, so we can only release it once */
603 if (do_close && state->compression_buffer) {
604 sshbuf_free(state->compression_buffer);
605 if (state->compression_out_started) {
606 z_streamp stream = &state->compression_out_stream;
607 debug("compress outgoing: "
608 "raw data %llu, compressed %llu, factor %.2f",
609 (unsigned long long)stream->total_in,
610 (unsigned long long)stream->total_out,
611 stream->total_in == 0 ? 0.0 :
612 (double) stream->total_out / stream->total_in);
613 if (state->compression_out_failures == 0)
616 if (state->compression_in_started) {
617 z_streamp stream = &state->compression_in_stream;
618 debug("compress incoming: "
619 "raw data %llu, compressed %llu, factor %.2f",
620 (unsigned long long)stream->total_out,
621 (unsigned long long)stream->total_in,
622 stream->total_out == 0 ? 0.0 :
623 (double) stream->total_in / stream->total_out);
624 if (state->compression_in_failures == 0)
628 cipher_free(state->send_context);
629 cipher_free(state->receive_context);
630 state->send_context = state->receive_context = NULL;
632 free(ssh->remote_ipaddr);
633 ssh->remote_ipaddr = NULL;
640 ssh_packet_close(struct ssh *ssh)
642 ssh_packet_close_internal(ssh, 1);
646 ssh_packet_clear_keys(struct ssh *ssh)
648 ssh_packet_close_internal(ssh, 0);
651 /* Sets remote side protocol flags. */
654 ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
656 ssh->state->remote_protocol_flags = protocol_flags;
659 /* Returns the remote protocol flags set earlier by the above function. */
662 ssh_packet_get_protocol_flags(struct ssh *ssh)
664 return ssh->state->remote_protocol_flags;
668 * Starts packet compression from the next packet on in both directions.
669 * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
673 ssh_packet_init_compression(struct ssh *ssh)
675 if (!ssh->state->compression_buffer &&
676 ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
677 return SSH_ERR_ALLOC_FAIL;
682 start_compression_out(struct ssh *ssh, int level)
684 if (level < 1 || level > 9)
685 return SSH_ERR_INVALID_ARGUMENT;
686 debug("Enabling compression at level %d.", level);
687 if (ssh->state->compression_out_started == 1)
688 deflateEnd(&ssh->state->compression_out_stream);
689 switch (deflateInit(&ssh->state->compression_out_stream, level)) {
691 ssh->state->compression_out_started = 1;
694 return SSH_ERR_ALLOC_FAIL;
696 return SSH_ERR_INTERNAL_ERROR;
702 start_compression_in(struct ssh *ssh)
704 if (ssh->state->compression_in_started == 1)
705 inflateEnd(&ssh->state->compression_in_stream);
706 switch (inflateInit(&ssh->state->compression_in_stream)) {
708 ssh->state->compression_in_started = 1;
711 return SSH_ERR_ALLOC_FAIL;
713 return SSH_ERR_INTERNAL_ERROR;
719 ssh_packet_start_compression(struct ssh *ssh, int level)
723 if (ssh->state->packet_compression)
724 return SSH_ERR_INTERNAL_ERROR;
725 ssh->state->packet_compression = 1;
726 if ((r = ssh_packet_init_compression(ssh)) != 0 ||
727 (r = start_compression_in(ssh)) != 0 ||
728 (r = start_compression_out(ssh, level)) != 0)
733 /* XXX remove need for separate compression buffer */
735 compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
740 if (ssh->state->compression_out_started != 1)
741 return SSH_ERR_INTERNAL_ERROR;
743 /* This case is not handled below. */
744 if (sshbuf_len(in) == 0)
747 /* Input is the contents of the input buffer. */
748 if ((ssh->state->compression_out_stream.next_in =
749 sshbuf_mutable_ptr(in)) == NULL)
750 return SSH_ERR_INTERNAL_ERROR;
751 ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
753 /* Loop compressing until deflate() returns with avail_out != 0. */
755 /* Set up fixed-size output buffer. */
756 ssh->state->compression_out_stream.next_out = buf;
757 ssh->state->compression_out_stream.avail_out = sizeof(buf);
759 /* Compress as much data into the buffer as possible. */
760 status = deflate(&ssh->state->compression_out_stream,
764 return SSH_ERR_ALLOC_FAIL;
766 /* Append compressed data to output_buffer. */
767 if ((r = sshbuf_put(out, buf, sizeof(buf) -
768 ssh->state->compression_out_stream.avail_out)) != 0)
773 ssh->state->compression_out_failures++;
774 return SSH_ERR_INVALID_FORMAT;
776 } while (ssh->state->compression_out_stream.avail_out == 0);
781 uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
786 if (ssh->state->compression_in_started != 1)
787 return SSH_ERR_INTERNAL_ERROR;
789 if ((ssh->state->compression_in_stream.next_in =
790 sshbuf_mutable_ptr(in)) == NULL)
791 return SSH_ERR_INTERNAL_ERROR;
792 ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
795 /* Set up fixed-size output buffer. */
796 ssh->state->compression_in_stream.next_out = buf;
797 ssh->state->compression_in_stream.avail_out = sizeof(buf);
799 status = inflate(&ssh->state->compression_in_stream,
803 if ((r = sshbuf_put(out, buf, sizeof(buf) -
804 ssh->state->compression_in_stream.avail_out)) != 0)
809 * Comments in zlib.h say that we should keep calling
810 * inflate() until we get an error. This appears to
811 * be the error that we get.
815 return SSH_ERR_INVALID_FORMAT;
817 return SSH_ERR_ALLOC_FAIL;
820 ssh->state->compression_in_failures++;
821 return SSH_ERR_INTERNAL_ERROR;
828 ssh_clear_newkeys(struct ssh *ssh, int mode)
830 if (ssh->kex && ssh->kex->newkeys[mode]) {
831 kex_free_newkeys(ssh->kex->newkeys[mode]);
832 ssh->kex->newkeys[mode] = NULL;
837 ssh_set_newkeys(struct ssh *ssh, int mode)
839 struct session_state *state = ssh->state;
842 struct sshcomp *comp;
843 struct sshcipher_ctx **ccp;
844 struct packet_state *ps;
845 u_int64_t *max_blocks;
849 debug2("set_newkeys: mode %d", mode);
851 if (mode == MODE_OUT) {
852 ccp = &state->send_context;
853 crypt_type = CIPHER_ENCRYPT;
855 max_blocks = &state->max_blocks_out;
857 ccp = &state->receive_context;
858 crypt_type = CIPHER_DECRYPT;
860 max_blocks = &state->max_blocks_in;
862 if (state->newkeys[mode] != NULL) {
863 debug("set_newkeys: rekeying, input %llu bytes %llu blocks, "
864 "output %llu bytes %llu blocks",
865 (unsigned long long)state->p_read.bytes,
866 (unsigned long long)state->p_read.blocks,
867 (unsigned long long)state->p_send.bytes,
868 (unsigned long long)state->p_send.blocks);
871 kex_free_newkeys(state->newkeys[mode]);
872 state->newkeys[mode] = NULL;
874 /* note that both bytes and the seqnr are not reset */
875 ps->packets = ps->blocks = 0;
876 /* move newkeys from kex to state */
877 if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
878 return SSH_ERR_INTERNAL_ERROR;
879 ssh->kex->newkeys[mode] = NULL;
880 enc = &state->newkeys[mode]->enc;
881 mac = &state->newkeys[mode]->mac;
882 comp = &state->newkeys[mode]->comp;
883 if (cipher_authlen(enc->cipher) == 0) {
884 if ((r = mac_init(mac)) != 0)
888 DBG(debug("cipher_init_context: %d", mode));
889 if ((r = cipher_init(ccp, enc->cipher, enc->key, enc->key_len,
890 enc->iv, enc->iv_len, crypt_type)) != 0)
892 if (!state->cipher_warning_done &&
893 (wmsg = cipher_warning_message(*ccp)) != NULL) {
894 error("Warning: %s", wmsg);
895 state->cipher_warning_done = 1;
897 /* Deleting the keys does not gain extra security */
898 /* explicit_bzero(enc->iv, enc->block_size);
899 explicit_bzero(enc->key, enc->key_len);
900 explicit_bzero(mac->key, mac->key_len); */
901 if ((comp->type == COMP_ZLIB ||
902 (comp->type == COMP_DELAYED &&
903 state->after_authentication)) && comp->enabled == 0) {
904 if ((r = ssh_packet_init_compression(ssh)) < 0)
906 if (mode == MODE_OUT) {
907 if ((r = start_compression_out(ssh, 6)) != 0)
910 if ((r = start_compression_in(ssh)) != 0)
916 * The 2^(blocksize*2) limit is too expensive for 3DES,
917 * so enforce a 1GB limit for small blocksizes.
918 * See RFC4344 section 3.2.
920 if (enc->block_size >= 16)
921 *max_blocks = (u_int64_t)1 << (enc->block_size*2);
923 *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
924 if (state->rekey_limit)
925 *max_blocks = MINIMUM(*max_blocks,
926 state->rekey_limit / enc->block_size);
927 debug("rekey after %llu blocks", (unsigned long long)*max_blocks);
931 #define MAX_PACKETS (1U<<31)
933 ssh_packet_need_rekeying(struct ssh *ssh, u_int outbound_packet_len)
935 struct session_state *state = ssh->state;
936 u_int32_t out_blocks;
938 /* XXX client can't cope with rekeying pre-auth */
939 if (!state->after_authentication)
942 /* Haven't keyed yet or KEX in progress. */
943 if (ssh->kex == NULL || ssh_packet_is_rekeying(ssh))
946 /* Peer can't rekey */
947 if (ssh->compat & SSH_BUG_NOREKEY)
951 * Permit one packet in or out per rekey - this allows us to
952 * make progress when rekey limits are very small.
954 if (state->p_send.packets == 0 && state->p_read.packets == 0)
957 /* Time-based rekeying */
958 if (state->rekey_interval != 0 &&
959 (int64_t)state->rekey_time + state->rekey_interval <= monotime())
963 * Always rekey when MAX_PACKETS sent in either direction
964 * As per RFC4344 section 3.1 we do this after 2^31 packets.
966 if (state->p_send.packets > MAX_PACKETS ||
967 state->p_read.packets > MAX_PACKETS)
970 /* Rekey after (cipher-specific) maxiumum blocks */
971 out_blocks = ROUNDUP(outbound_packet_len,
972 state->newkeys[MODE_OUT]->enc.block_size);
973 return (state->max_blocks_out &&
974 (state->p_send.blocks + out_blocks > state->max_blocks_out)) ||
975 (state->max_blocks_in &&
976 (state->p_read.blocks > state->max_blocks_in));
980 * Delayed compression for SSH2 is enabled after authentication:
981 * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
982 * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
985 ssh_packet_enable_delayed_compress(struct ssh *ssh)
987 struct session_state *state = ssh->state;
988 struct sshcomp *comp = NULL;
992 * Remember that we are past the authentication step, so rekeying
993 * with COMP_DELAYED will turn on compression immediately.
995 state->after_authentication = 1;
996 for (mode = 0; mode < MODE_MAX; mode++) {
997 /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
998 if (state->newkeys[mode] == NULL)
1000 comp = &state->newkeys[mode]->comp;
1001 if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1002 if ((r = ssh_packet_init_compression(ssh)) != 0)
1004 if (mode == MODE_OUT) {
1005 if ((r = start_compression_out(ssh, 6)) != 0)
1008 if ((r = start_compression_in(ssh)) != 0)
1017 /* Used to mute debug logging for noisy packet types */
1019 ssh_packet_log_type(u_char type)
1022 case SSH2_MSG_CHANNEL_DATA:
1023 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1024 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1032 * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1035 ssh_packet_send2_wrapped(struct ssh *ssh)
1037 struct session_state *state = ssh->state;
1038 u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1039 u_char tmp, padlen, pad = 0;
1040 u_int authlen = 0, aadlen = 0;
1042 struct sshenc *enc = NULL;
1043 struct sshmac *mac = NULL;
1044 struct sshcomp *comp = NULL;
1047 if (state->newkeys[MODE_OUT] != NULL) {
1048 enc = &state->newkeys[MODE_OUT]->enc;
1049 mac = &state->newkeys[MODE_OUT]->mac;
1050 comp = &state->newkeys[MODE_OUT]->comp;
1051 /* disable mac for authenticated encryption */
1052 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1055 block_size = enc ? enc->block_size : 8;
1056 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1058 type = (sshbuf_ptr(state->outgoing_packet))[5];
1059 if (ssh_packet_log_type(type))
1060 debug3("send packet: type %u", type);
1062 fprintf(stderr, "plain: ");
1063 sshbuf_dump(state->outgoing_packet, stderr);
1066 if (comp && comp->enabled) {
1067 len = sshbuf_len(state->outgoing_packet);
1068 /* skip header, compress only payload */
1069 if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1071 sshbuf_reset(state->compression_buffer);
1072 if ((r = compress_buffer(ssh, state->outgoing_packet,
1073 state->compression_buffer)) != 0)
1075 sshbuf_reset(state->outgoing_packet);
1076 if ((r = sshbuf_put(state->outgoing_packet,
1077 "\0\0\0\0\0", 5)) != 0 ||
1078 (r = sshbuf_putb(state->outgoing_packet,
1079 state->compression_buffer)) != 0)
1081 DBG(debug("compression: raw %d compressed %zd", len,
1082 sshbuf_len(state->outgoing_packet)));
1085 /* sizeof (packet_len + pad_len + payload) */
1086 len = sshbuf_len(state->outgoing_packet);
1089 * calc size of padding, alloc space, get random data,
1090 * minimum padding is 4 bytes
1092 len -= aadlen; /* packet length is not encrypted for EtM modes */
1093 padlen = block_size - (len % block_size);
1095 padlen += block_size;
1096 if (state->extra_pad) {
1097 tmp = state->extra_pad;
1099 ROUNDUP(state->extra_pad, block_size);
1100 /* check if roundup overflowed */
1101 if (state->extra_pad < tmp)
1102 return SSH_ERR_INVALID_ARGUMENT;
1103 tmp = (len + padlen) % state->extra_pad;
1104 /* Check whether pad calculation below will underflow */
1105 if (tmp > state->extra_pad)
1106 return SSH_ERR_INVALID_ARGUMENT;
1107 pad = state->extra_pad - tmp;
1108 DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1109 __func__, pad, len, padlen, state->extra_pad));
1112 /* Check whether padlen calculation overflowed */
1114 return SSH_ERR_INVALID_ARGUMENT; /* overflow */
1115 state->extra_pad = 0;
1117 if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1119 if (enc && !cipher_ctx_is_plaintext(state->send_context)) {
1120 /* random padding */
1121 arc4random_buf(cp, padlen);
1124 explicit_bzero(cp, padlen);
1126 /* sizeof (packet_len + pad_len + payload + padding) */
1127 len = sshbuf_len(state->outgoing_packet);
1128 cp = sshbuf_mutable_ptr(state->outgoing_packet);
1130 r = SSH_ERR_INTERNAL_ERROR;
1133 /* packet_length includes payload, padding and padding length field */
1134 POKE_U32(cp, len - 4);
1136 DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1137 len, padlen, aadlen));
1139 /* compute MAC over seqnr and packet(length fields, payload, padding) */
1140 if (mac && mac->enabled && !mac->etm) {
1141 if ((r = mac_compute(mac, state->p_send.seqnr,
1142 sshbuf_ptr(state->outgoing_packet), len,
1143 macbuf, sizeof(macbuf))) != 0)
1145 DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1147 /* encrypt packet and append to output buffer. */
1148 if ((r = sshbuf_reserve(state->output,
1149 sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1151 if ((r = cipher_crypt(state->send_context, state->p_send.seqnr, cp,
1152 sshbuf_ptr(state->outgoing_packet),
1153 len - aadlen, aadlen, authlen)) != 0)
1155 /* append unencrypted MAC */
1156 if (mac && mac->enabled) {
1158 /* EtM: compute mac over aadlen + cipher text */
1159 if ((r = mac_compute(mac, state->p_send.seqnr,
1160 cp, len, macbuf, sizeof(macbuf))) != 0)
1162 DBG(debug("done calc MAC(EtM) out #%d",
1163 state->p_send.seqnr));
1165 if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1169 fprintf(stderr, "encrypted: ");
1170 sshbuf_dump(state->output, stderr);
1172 /* increment sequence number for outgoing packets */
1173 if (++state->p_send.seqnr == 0)
1174 logit("outgoing seqnr wraps around");
1175 if (++state->p_send.packets == 0)
1176 if (!(ssh->compat & SSH_BUG_NOREKEY))
1177 return SSH_ERR_NEED_REKEY;
1178 state->p_send.blocks += len / block_size;
1179 state->p_send.bytes += len;
1180 sshbuf_reset(state->outgoing_packet);
1182 if (type == SSH2_MSG_NEWKEYS)
1183 r = ssh_set_newkeys(ssh, MODE_OUT);
1184 else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1185 r = ssh_packet_enable_delayed_compress(ssh);
1192 /* returns non-zero if the specified packet type is usec by KEX */
1194 ssh_packet_type_is_kex(u_char type)
1197 type >= SSH2_MSG_TRANSPORT_MIN &&
1198 type <= SSH2_MSG_TRANSPORT_MAX &&
1199 type != SSH2_MSG_SERVICE_REQUEST &&
1200 type != SSH2_MSG_SERVICE_ACCEPT &&
1201 type != SSH2_MSG_EXT_INFO;
1205 ssh_packet_send2(struct ssh *ssh)
1207 struct session_state *state = ssh->state;
1212 if (sshbuf_len(state->outgoing_packet) < 6)
1213 return SSH_ERR_INTERNAL_ERROR;
1214 type = sshbuf_ptr(state->outgoing_packet)[5];
1215 need_rekey = !ssh_packet_type_is_kex(type) &&
1216 ssh_packet_need_rekeying(ssh, sshbuf_len(state->outgoing_packet));
1219 * During rekeying we can only send key exchange messages.
1220 * Queue everything else.
1222 if ((need_rekey || state->rekeying) && !ssh_packet_type_is_kex(type)) {
1224 debug3("%s: rekex triggered", __func__);
1225 debug("enqueue packet: %u", type);
1226 p = calloc(1, sizeof(*p));
1228 return SSH_ERR_ALLOC_FAIL;
1230 p->payload = state->outgoing_packet;
1231 TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1232 state->outgoing_packet = sshbuf_new();
1233 if (state->outgoing_packet == NULL)
1234 return SSH_ERR_ALLOC_FAIL;
1237 * This packet triggered a rekey, so send the
1239 * NB. reenters this function via kex_start_rekex().
1241 return kex_start_rekex(ssh);
1246 /* rekeying starts with sending KEXINIT */
1247 if (type == SSH2_MSG_KEXINIT)
1248 state->rekeying = 1;
1250 if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1253 /* after a NEWKEYS message we can send the complete queue */
1254 if (type == SSH2_MSG_NEWKEYS) {
1255 state->rekeying = 0;
1256 state->rekey_time = monotime();
1257 while ((p = TAILQ_FIRST(&state->outgoing))) {
1260 * If this packet triggers a rekex, then skip the
1261 * remaining packets in the queue for now.
1262 * NB. re-enters this function via kex_start_rekex.
1264 if (ssh_packet_need_rekeying(ssh,
1265 sshbuf_len(p->payload))) {
1266 debug3("%s: queued packet triggered rekex",
1268 return kex_start_rekex(ssh);
1270 debug("dequeue packet: %u", type);
1271 sshbuf_free(state->outgoing_packet);
1272 state->outgoing_packet = p->payload;
1273 TAILQ_REMOVE(&state->outgoing, p, next);
1274 memset(p, 0, sizeof(*p));
1276 if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1284 * Waits until a packet has been received, and returns its type. Note that
1285 * no other data is processed until this returns, so this function should not
1286 * be used during the interactive session.
1290 ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1292 struct session_state *state = ssh->state;
1293 int len, r, ms_remain;
1296 struct timeval timeout, start, *timeoutp = NULL;
1298 DBG(debug("packet_read()"));
1300 setp = calloc(howmany(state->connection_in + 1,
1301 NFDBITS), sizeof(fd_mask));
1303 return SSH_ERR_ALLOC_FAIL;
1306 * Since we are blocking, ensure that all written packets have
1309 if ((r = ssh_packet_write_wait(ssh)) != 0)
1312 /* Stay in the loop until we have received a complete packet. */
1314 /* Try to read a packet from the buffer. */
1315 r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1318 /* If we got a packet, return it. */
1319 if (*typep != SSH_MSG_NONE)
1322 * Otherwise, wait for some data to arrive, add it to the
1323 * buffer, and try again.
1325 memset(setp, 0, howmany(state->connection_in + 1,
1326 NFDBITS) * sizeof(fd_mask));
1327 FD_SET(state->connection_in, setp);
1329 if (state->packet_timeout_ms > 0) {
1330 ms_remain = state->packet_timeout_ms;
1331 timeoutp = &timeout;
1333 /* Wait for some data to arrive. */
1335 if (state->packet_timeout_ms != -1) {
1336 ms_to_timeval(&timeout, ms_remain);
1337 monotime_tv(&start);
1339 if ((r = select(state->connection_in + 1, setp,
1340 NULL, NULL, timeoutp)) >= 0)
1342 if (errno != EAGAIN && errno != EINTR &&
1343 errno != EWOULDBLOCK)
1345 if (state->packet_timeout_ms == -1)
1347 ms_subtract_diff(&start, &ms_remain);
1348 if (ms_remain <= 0) {
1354 r = SSH_ERR_CONN_TIMEOUT;
1357 /* Read data from the socket. */
1358 len = read(state->connection_in, buf, sizeof(buf));
1360 r = SSH_ERR_CONN_CLOSED;
1364 r = SSH_ERR_SYSTEM_ERROR;
1368 /* Append it to the buffer. */
1369 if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1378 ssh_packet_read(struct ssh *ssh)
1383 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1384 fatal("%s: %s", __func__, ssh_err(r));
1389 * Waits until a packet has been received, verifies that its type matches
1390 * that given, and gives a fatal error and exits if there is a mismatch.
1394 ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1399 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1401 if (type != expected_type) {
1402 if ((r = sshpkt_disconnect(ssh,
1403 "Protocol error: expected packet type %d, got %d",
1404 expected_type, type)) != 0)
1406 return SSH_ERR_PROTOCOL_ERROR;
1412 ssh_packet_read_poll2_mux(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1414 struct session_state *state = ssh->state;
1420 return SSH_ERR_INTERNAL_ERROR;
1421 *typep = SSH_MSG_NONE;
1422 cp = sshbuf_ptr(state->input);
1423 if (state->packlen == 0) {
1424 if (sshbuf_len(state->input) < 4 + 1)
1425 return 0; /* packet is incomplete */
1426 state->packlen = PEEK_U32(cp);
1427 if (state->packlen < 4 + 1 ||
1428 state->packlen > PACKET_MAX_SIZE)
1429 return SSH_ERR_MESSAGE_INCOMPLETE;
1431 need = state->packlen + 4;
1432 if (sshbuf_len(state->input) < need)
1433 return 0; /* packet is incomplete */
1434 sshbuf_reset(state->incoming_packet);
1435 if ((r = sshbuf_put(state->incoming_packet, cp + 4,
1436 state->packlen)) != 0 ||
1437 (r = sshbuf_consume(state->input, need)) != 0 ||
1438 (r = sshbuf_get_u8(state->incoming_packet, NULL)) != 0 ||
1439 (r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1441 if (ssh_packet_log_type(*typep))
1442 debug3("%s: type %u", __func__, *typep);
1443 /* sshbuf_dump(state->incoming_packet, stderr); */
1444 /* reset for next packet */
1450 ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1452 struct session_state *state = ssh->state;
1455 u_int maclen, aadlen = 0, authlen = 0, block_size;
1456 struct sshenc *enc = NULL;
1457 struct sshmac *mac = NULL;
1458 struct sshcomp *comp = NULL;
1462 return ssh_packet_read_poll2_mux(ssh, typep, seqnr_p);
1464 *typep = SSH_MSG_NONE;
1466 if (state->packet_discard)
1469 if (state->newkeys[MODE_IN] != NULL) {
1470 enc = &state->newkeys[MODE_IN]->enc;
1471 mac = &state->newkeys[MODE_IN]->mac;
1472 comp = &state->newkeys[MODE_IN]->comp;
1473 /* disable mac for authenticated encryption */
1474 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1477 maclen = mac && mac->enabled ? mac->mac_len : 0;
1478 block_size = enc ? enc->block_size : 8;
1479 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1481 if (aadlen && state->packlen == 0) {
1482 if (cipher_get_length(state->receive_context,
1483 &state->packlen, state->p_read.seqnr,
1484 sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1486 if (state->packlen < 1 + 4 ||
1487 state->packlen > PACKET_MAX_SIZE) {
1489 sshbuf_dump(state->input, stderr);
1491 logit("Bad packet length %u.", state->packlen);
1492 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1494 return SSH_ERR_CONN_CORRUPT;
1496 sshbuf_reset(state->incoming_packet);
1497 } else if (state->packlen == 0) {
1499 * check if input size is less than the cipher block size,
1500 * decrypt first block and extract length of incoming packet
1502 if (sshbuf_len(state->input) < block_size)
1504 sshbuf_reset(state->incoming_packet);
1505 if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1508 if ((r = cipher_crypt(state->receive_context,
1509 state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1510 block_size, 0, 0)) != 0)
1512 state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1513 if (state->packlen < 1 + 4 ||
1514 state->packlen > PACKET_MAX_SIZE) {
1516 fprintf(stderr, "input: \n");
1517 sshbuf_dump(state->input, stderr);
1518 fprintf(stderr, "incoming_packet: \n");
1519 sshbuf_dump(state->incoming_packet, stderr);
1521 logit("Bad packet length %u.", state->packlen);
1522 return ssh_packet_start_discard(ssh, enc, mac, 0,
1525 if ((r = sshbuf_consume(state->input, block_size)) != 0)
1528 DBG(debug("input: packet len %u", state->packlen+4));
1531 /* only the payload is encrypted */
1532 need = state->packlen;
1535 * the payload size and the payload are encrypted, but we
1536 * have a partial packet of block_size bytes
1538 need = 4 + state->packlen - block_size;
1540 DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1541 " aadlen %d", block_size, need, maclen, authlen, aadlen));
1542 if (need % block_size != 0) {
1543 logit("padding error: need %d block %d mod %d",
1544 need, block_size, need % block_size);
1545 return ssh_packet_start_discard(ssh, enc, mac, 0,
1546 PACKET_MAX_SIZE - block_size);
1549 * check if the entire packet has been received and
1550 * decrypt into incoming_packet:
1551 * 'aadlen' bytes are unencrypted, but authenticated.
1552 * 'need' bytes are encrypted, followed by either
1553 * 'authlen' bytes of authentication tag or
1554 * 'maclen' bytes of message authentication code.
1556 if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1557 return 0; /* packet is incomplete */
1559 fprintf(stderr, "read_poll enc/full: ");
1560 sshbuf_dump(state->input, stderr);
1562 /* EtM: check mac over encrypted input */
1563 if (mac && mac->enabled && mac->etm) {
1564 if ((r = mac_check(mac, state->p_read.seqnr,
1565 sshbuf_ptr(state->input), aadlen + need,
1566 sshbuf_ptr(state->input) + aadlen + need + authlen,
1568 if (r == SSH_ERR_MAC_INVALID)
1569 logit("Corrupted MAC on input.");
1573 if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1576 if ((r = cipher_crypt(state->receive_context, state->p_read.seqnr, cp,
1577 sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1579 if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1581 if (mac && mac->enabled) {
1582 /* Not EtM: check MAC over cleartext */
1583 if (!mac->etm && (r = mac_check(mac, state->p_read.seqnr,
1584 sshbuf_ptr(state->incoming_packet),
1585 sshbuf_len(state->incoming_packet),
1586 sshbuf_ptr(state->input), maclen)) != 0) {
1587 if (r != SSH_ERR_MAC_INVALID)
1589 logit("Corrupted MAC on input.");
1590 if (need + block_size > PACKET_MAX_SIZE)
1591 return SSH_ERR_INTERNAL_ERROR;
1592 return ssh_packet_start_discard(ssh, enc, mac,
1593 sshbuf_len(state->incoming_packet),
1594 PACKET_MAX_SIZE - need - block_size);
1596 /* Remove MAC from input buffer */
1597 DBG(debug("MAC #%d ok", state->p_read.seqnr));
1598 if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1601 if (seqnr_p != NULL)
1602 *seqnr_p = state->p_read.seqnr;
1603 if (++state->p_read.seqnr == 0)
1604 logit("incoming seqnr wraps around");
1605 if (++state->p_read.packets == 0)
1606 if (!(ssh->compat & SSH_BUG_NOREKEY))
1607 return SSH_ERR_NEED_REKEY;
1608 state->p_read.blocks += (state->packlen + 4) / block_size;
1609 state->p_read.bytes += state->packlen + 4;
1612 padlen = sshbuf_ptr(state->incoming_packet)[4];
1613 DBG(debug("input: padlen %d", padlen));
1615 if ((r = sshpkt_disconnect(ssh,
1616 "Corrupted padlen %d on input.", padlen)) != 0 ||
1617 (r = ssh_packet_write_wait(ssh)) != 0)
1619 return SSH_ERR_CONN_CORRUPT;
1622 /* skip packet size + padlen, discard padding */
1623 if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1624 ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1627 DBG(debug("input: len before de-compress %zd",
1628 sshbuf_len(state->incoming_packet)));
1629 if (comp && comp->enabled) {
1630 sshbuf_reset(state->compression_buffer);
1631 if ((r = uncompress_buffer(ssh, state->incoming_packet,
1632 state->compression_buffer)) != 0)
1634 sshbuf_reset(state->incoming_packet);
1635 if ((r = sshbuf_putb(state->incoming_packet,
1636 state->compression_buffer)) != 0)
1638 DBG(debug("input: len after de-compress %zd",
1639 sshbuf_len(state->incoming_packet)));
1642 * get packet type, implies consume.
1643 * return length of payload (without type field)
1645 if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1647 if (ssh_packet_log_type(*typep))
1648 debug3("receive packet: type %u", *typep);
1649 if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1650 if ((r = sshpkt_disconnect(ssh,
1651 "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1652 (r = ssh_packet_write_wait(ssh)) != 0)
1654 return SSH_ERR_PROTOCOL_ERROR;
1656 if (state->hook_in != NULL &&
1657 (r = state->hook_in(ssh, state->incoming_packet, typep,
1658 state->hook_in_ctx)) != 0)
1660 if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1661 r = ssh_packet_enable_delayed_compress(ssh);
1665 fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1666 sshbuf_dump(state->incoming_packet, stderr);
1668 /* reset for next packet */
1671 /* do we need to rekey? */
1672 if (ssh_packet_need_rekeying(ssh, 0)) {
1673 debug3("%s: rekex triggered", __func__);
1674 if ((r = kex_start_rekex(ssh)) != 0)
1682 ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1684 struct session_state *state = ssh->state;
1685 u_int reason, seqnr;
1691 r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1695 state->keep_alive_timeouts = 0;
1696 DBG(debug("received packet type %d", *typep));
1699 case SSH2_MSG_IGNORE:
1700 debug3("Received SSH2_MSG_IGNORE");
1702 case SSH2_MSG_DEBUG:
1703 if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1704 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1705 (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1709 debug("Remote: %.900s", msg);
1712 case SSH2_MSG_DISCONNECT:
1713 if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1714 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1716 /* Ignore normal client exit notifications */
1717 do_log2(ssh->state->server_side &&
1718 reason == SSH2_DISCONNECT_BY_APPLICATION ?
1719 SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1720 "Received disconnect from %s port %d:"
1721 "%u: %.400s", ssh_remote_ipaddr(ssh),
1722 ssh_remote_port(ssh), reason, msg);
1724 return SSH_ERR_DISCONNECTED;
1725 case SSH2_MSG_UNIMPLEMENTED:
1726 if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1728 debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1738 * Buffers the given amount of input characters. This is intended to be used
1739 * together with packet_read_poll.
1743 ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1745 struct session_state *state = ssh->state;
1748 if (state->packet_discard) {
1749 state->keep_alive_timeouts = 0; /* ?? */
1750 if (len >= state->packet_discard) {
1751 if ((r = ssh_packet_stop_discard(ssh)) != 0)
1754 state->packet_discard -= len;
1757 if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1764 ssh_packet_remaining(struct ssh *ssh)
1766 return sshbuf_len(ssh->state->incoming_packet);
1770 * Sends a diagnostic message from the server to the client. This message
1771 * can be sent at any time (but not while constructing another message). The
1772 * message is printed immediately, but only if the client is being executed
1773 * in verbose mode. These messages are primarily intended to ease debugging
1774 * authentication problems. The length of the formatted message must not
1775 * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1778 ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1784 if ((ssh->compat & SSH_BUG_DEBUG))
1787 va_start(args, fmt);
1788 vsnprintf(buf, sizeof(buf), fmt, args);
1791 debug3("sending debug message: %s", buf);
1793 if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1794 (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1795 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1796 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1797 (r = sshpkt_send(ssh)) != 0 ||
1798 (r = ssh_packet_write_wait(ssh)) != 0)
1799 fatal("%s: %s", __func__, ssh_err(r));
1803 sshpkt_fmt_connection_id(struct ssh *ssh, char *s, size_t l)
1805 snprintf(s, l, "%.200s%s%s port %d",
1806 ssh->log_preamble ? ssh->log_preamble : "",
1807 ssh->log_preamble ? " " : "",
1808 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1812 * Pretty-print connection-terminating errors and exit.
1815 sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1817 char remote_id[512];
1819 sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1822 case SSH_ERR_CONN_CLOSED:
1823 ssh_packet_clear_keys(ssh);
1824 logdie("Connection closed by %s", remote_id);
1825 case SSH_ERR_CONN_TIMEOUT:
1826 ssh_packet_clear_keys(ssh);
1827 logdie("Connection %s %s timed out",
1828 ssh->state->server_side ? "from" : "to", remote_id);
1829 case SSH_ERR_DISCONNECTED:
1830 ssh_packet_clear_keys(ssh);
1831 logdie("Disconnected from %s", remote_id);
1832 case SSH_ERR_SYSTEM_ERROR:
1833 if (errno == ECONNRESET) {
1834 ssh_packet_clear_keys(ssh);
1835 logdie("Connection reset by %s", remote_id);
1838 case SSH_ERR_NO_CIPHER_ALG_MATCH:
1839 case SSH_ERR_NO_MAC_ALG_MATCH:
1840 case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1841 case SSH_ERR_NO_KEX_ALG_MATCH:
1842 case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1843 if (ssh && ssh->kex && ssh->kex->failed_choice) {
1844 BLACKLIST_NOTIFY(BLACKLIST_AUTH_FAIL, "ssh");
1845 ssh_packet_clear_keys(ssh);
1846 logdie("Unable to negotiate with %s: %s. "
1847 "Their offer: %s", remote_id, ssh_err(r),
1848 ssh->kex->failed_choice);
1852 ssh_packet_clear_keys(ssh);
1853 logdie("%s%sConnection %s %s: %s",
1854 tag != NULL ? tag : "", tag != NULL ? ": " : "",
1855 ssh->state->server_side ? "from" : "to",
1856 remote_id, ssh_err(r));
1861 * Logs the error plus constructs and sends a disconnect packet, closes the
1862 * connection, and exits. This function never returns. The error message
1863 * should not contain a newline. The length of the formatted message must
1864 * not exceed 1024 bytes.
1867 ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1869 char buf[1024], remote_id[512];
1871 static int disconnecting = 0;
1874 if (disconnecting) /* Guard against recursive invocations. */
1875 fatal("packet_disconnect called recursively.");
1879 * Format the message. Note that the caller must make sure the
1880 * message is of limited size.
1882 sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1883 va_start(args, fmt);
1884 vsnprintf(buf, sizeof(buf), fmt, args);
1887 /* Display the error locally */
1888 logit("Disconnecting %s: %.100s", remote_id, buf);
1891 * Send the disconnect message to the other side, and wait
1892 * for it to get sent.
1894 if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1895 sshpkt_fatal(ssh, __func__, r);
1897 if ((r = ssh_packet_write_wait(ssh)) != 0)
1898 sshpkt_fatal(ssh, __func__, r);
1900 /* Close the connection. */
1901 ssh_packet_close(ssh);
1906 * Checks if there is any buffered output, and tries to write some of
1910 ssh_packet_write_poll(struct ssh *ssh)
1912 struct session_state *state = ssh->state;
1913 int len = sshbuf_len(state->output);
1917 len = write(state->connection_out,
1918 sshbuf_ptr(state->output), len);
1920 if (errno == EINTR || errno == EAGAIN ||
1921 errno == EWOULDBLOCK)
1923 return SSH_ERR_SYSTEM_ERROR;
1926 return SSH_ERR_CONN_CLOSED;
1927 if ((r = sshbuf_consume(state->output, len)) != 0)
1934 * Calls packet_write_poll repeatedly until all pending output data has been
1938 ssh_packet_write_wait(struct ssh *ssh)
1941 int ret, r, ms_remain = 0;
1942 struct timeval start, timeout, *timeoutp = NULL;
1943 struct session_state *state = ssh->state;
1945 setp = calloc(howmany(state->connection_out + 1,
1946 NFDBITS), sizeof(fd_mask));
1948 return SSH_ERR_ALLOC_FAIL;
1949 if ((r = ssh_packet_write_poll(ssh)) != 0) {
1953 while (ssh_packet_have_data_to_write(ssh)) {
1954 memset(setp, 0, howmany(state->connection_out + 1,
1955 NFDBITS) * sizeof(fd_mask));
1956 FD_SET(state->connection_out, setp);
1958 if (state->packet_timeout_ms > 0) {
1959 ms_remain = state->packet_timeout_ms;
1960 timeoutp = &timeout;
1963 if (state->packet_timeout_ms != -1) {
1964 ms_to_timeval(&timeout, ms_remain);
1965 monotime_tv(&start);
1967 if ((ret = select(state->connection_out + 1,
1968 NULL, setp, NULL, timeoutp)) >= 0)
1970 if (errno != EAGAIN && errno != EINTR &&
1971 errno != EWOULDBLOCK)
1973 if (state->packet_timeout_ms == -1)
1975 ms_subtract_diff(&start, &ms_remain);
1976 if (ms_remain <= 0) {
1983 return SSH_ERR_CONN_TIMEOUT;
1985 if ((r = ssh_packet_write_poll(ssh)) != 0) {
1994 /* Returns true if there is buffered data to write to the connection. */
1997 ssh_packet_have_data_to_write(struct ssh *ssh)
1999 return sshbuf_len(ssh->state->output) != 0;
2002 /* Returns true if there is not too much data to write to the connection. */
2005 ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
2007 if (ssh->state->interactive_mode)
2008 return sshbuf_len(ssh->state->output) < 16384;
2010 return sshbuf_len(ssh->state->output) < 128 * 1024;
2014 ssh_packet_set_tos(struct ssh *ssh, int tos)
2016 #ifndef IP_TOS_IS_BROKEN
2017 if (!ssh_packet_connection_is_on_socket(ssh) || tos == INT_MAX)
2019 switch (ssh_packet_connection_af(ssh)) {
2022 debug3("%s: set IP_TOS 0x%02x", __func__, tos);
2023 if (setsockopt(ssh->state->connection_in,
2024 IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2025 error("setsockopt IP_TOS %d: %.100s:",
2026 tos, strerror(errno));
2028 # endif /* IP_TOS */
2031 debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
2032 if (setsockopt(ssh->state->connection_in,
2033 IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2034 error("setsockopt IPV6_TCLASS %d: %.100s:",
2035 tos, strerror(errno));
2037 # endif /* IPV6_TCLASS */
2039 #endif /* IP_TOS_IS_BROKEN */
2042 /* Informs that the current session is interactive. Sets IP flags for that. */
2045 ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
2047 struct session_state *state = ssh->state;
2049 if (state->set_interactive_called)
2051 state->set_interactive_called = 1;
2053 /* Record that we are in interactive mode. */
2054 state->interactive_mode = interactive;
2056 /* Only set socket options if using a socket. */
2057 if (!ssh_packet_connection_is_on_socket(ssh))
2059 set_nodelay(state->connection_in);
2060 ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2064 /* Returns true if the current connection is interactive. */
2067 ssh_packet_is_interactive(struct ssh *ssh)
2069 return ssh->state->interactive_mode;
2073 ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
2075 struct session_state *state = ssh->state;
2077 if (state->set_maxsize_called) {
2078 logit("packet_set_maxsize: called twice: old %d new %d",
2079 state->max_packet_size, s);
2082 if (s < 4 * 1024 || s > 1024 * 1024) {
2083 logit("packet_set_maxsize: bad size %d", s);
2086 state->set_maxsize_called = 1;
2087 debug("packet_set_maxsize: setting to %d", s);
2088 state->max_packet_size = s;
2093 ssh_packet_inc_alive_timeouts(struct ssh *ssh)
2095 return ++ssh->state->keep_alive_timeouts;
2099 ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
2101 ssh->state->keep_alive_timeouts = ka;
2105 ssh_packet_get_maxsize(struct ssh *ssh)
2107 return ssh->state->max_packet_size;
2111 ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, u_int32_t seconds)
2113 debug3("rekey after %llu bytes, %u seconds", (unsigned long long)bytes,
2114 (unsigned int)seconds);
2115 ssh->state->rekey_limit = bytes;
2116 ssh->state->rekey_interval = seconds;
2120 ssh_packet_get_rekey_timeout(struct ssh *ssh)
2124 seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
2126 return (seconds <= 0 ? 1 : seconds);
2130 ssh_packet_set_server(struct ssh *ssh)
2132 ssh->state->server_side = 1;
2136 ssh_packet_set_authenticated(struct ssh *ssh)
2138 ssh->state->after_authentication = 1;
2142 ssh_packet_get_input(struct ssh *ssh)
2144 return (void *)ssh->state->input;
2148 ssh_packet_get_output(struct ssh *ssh)
2150 return (void *)ssh->state->output;
2153 /* Reset after_authentication and reset compression in post-auth privsep */
2155 ssh_packet_set_postauth(struct ssh *ssh)
2159 debug("%s: called", __func__);
2160 /* This was set in net child, but is not visible in user child */
2161 ssh->state->after_authentication = 1;
2162 ssh->state->rekeying = 0;
2163 if ((r = ssh_packet_enable_delayed_compress(ssh)) != 0)
2168 /* Packet state (de-)serialization for privsep */
2170 /* turn kex into a blob for packet state serialization */
2172 kex_to_blob(struct sshbuf *m, struct kex *kex)
2176 if ((r = sshbuf_put_string(m, kex->session_id,
2177 kex->session_id_len)) != 0 ||
2178 (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2179 (r = sshbuf_put_cstring(m, kex->hostkey_alg)) != 0 ||
2180 (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2181 (r = sshbuf_put_u32(m, kex->hostkey_nid)) != 0 ||
2182 (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2183 (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2184 (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2185 (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2186 (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2187 (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2192 /* turn key exchange results into a blob for packet state serialization */
2194 newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2197 struct sshcipher_ctx *cc;
2198 struct sshcomp *comp;
2201 struct newkeys *newkey;
2204 if ((newkey = ssh->state->newkeys[mode]) == NULL)
2205 return SSH_ERR_INTERNAL_ERROR;
2208 comp = &newkey->comp;
2209 cc = (mode == MODE_OUT) ? ssh->state->send_context :
2210 ssh->state->receive_context;
2211 if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2213 if ((b = sshbuf_new()) == NULL)
2214 return SSH_ERR_ALLOC_FAIL;
2215 if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2216 (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2217 (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2218 (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2219 (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2221 if (cipher_authlen(enc->cipher) == 0) {
2222 if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2223 (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2224 (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2227 if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2228 (r = sshbuf_put_cstring(b, comp->name)) != 0)
2230 r = sshbuf_put_stringb(m, b);
2236 /* serialize packet state into a blob */
2238 ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2240 struct session_state *state = ssh->state;
2243 if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2244 (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2245 (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
2246 (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
2247 (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
2248 (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2249 (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2250 (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2251 (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2252 (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2253 (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2254 (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2255 (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0 ||
2256 (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2257 (r = sshbuf_put_stringb(m, state->output)) != 0)
2263 /* restore key exchange results from blob for packet state de-serialization */
2265 newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2267 struct sshbuf *b = NULL;
2268 struct sshcomp *comp;
2271 struct newkeys *newkey = NULL;
2272 size_t keylen, ivlen, maclen;
2275 if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2276 r = SSH_ERR_ALLOC_FAIL;
2279 if ((r = sshbuf_froms(m, &b)) != 0)
2282 sshbuf_dump(b, stderr);
2286 comp = &newkey->comp;
2288 if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2289 (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2290 (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2291 (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2292 (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2294 if ((enc->cipher = cipher_by_name(enc->name)) == NULL) {
2295 r = SSH_ERR_INVALID_FORMAT;
2298 if (cipher_authlen(enc->cipher) == 0) {
2299 if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2301 if ((r = mac_setup(mac, mac->name)) != 0)
2303 if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2304 (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2306 if (maclen > mac->key_len) {
2307 r = SSH_ERR_INVALID_FORMAT;
2310 mac->key_len = maclen;
2312 if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2313 (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2315 if (sshbuf_len(b) != 0) {
2316 r = SSH_ERR_INVALID_FORMAT;
2319 enc->key_len = keylen;
2320 enc->iv_len = ivlen;
2321 ssh->kex->newkeys[mode] = newkey;
2330 /* restore kex from blob for packet state de-serialization */
2332 kex_from_blob(struct sshbuf *m, struct kex **kexp)
2337 if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2338 (kex->my = sshbuf_new()) == NULL ||
2339 (kex->peer = sshbuf_new()) == NULL) {
2340 r = SSH_ERR_ALLOC_FAIL;
2343 if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2344 (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2345 (r = sshbuf_get_cstring(m, &kex->hostkey_alg, NULL)) != 0 ||
2346 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2347 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_nid)) != 0 ||
2348 (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2349 (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2350 (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2351 (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2352 (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2353 (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2359 if (r != 0 || kexp == NULL) {
2361 sshbuf_free(kex->my);
2362 sshbuf_free(kex->peer);
2374 * Restore packet state from content of blob 'm' (de-serialization).
2375 * Note that 'm' will be partially consumed on parsing or any other errors.
2378 ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2380 struct session_state *state = ssh->state;
2381 const u_char *input, *output;
2385 if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2386 (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2387 (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
2388 (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
2389 (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
2390 (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2391 (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2392 (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2393 (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2394 (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2395 (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2396 (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2397 (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2400 * We set the time here so that in post-auth privsep slave we
2401 * count from the completion of the authentication.
2403 state->rekey_time = monotime();
2404 /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2405 if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2406 (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2409 if ((r = ssh_packet_set_postauth(ssh)) != 0)
2412 sshbuf_reset(state->input);
2413 sshbuf_reset(state->output);
2414 if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2415 (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2416 (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2417 (r = sshbuf_put(state->output, output, olen)) != 0)
2421 return SSH_ERR_INVALID_FORMAT;
2422 debug3("%s: done", __func__);
2428 /* put data to the outgoing packet */
2431 sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2433 return sshbuf_put(ssh->state->outgoing_packet, v, len);
2437 sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2439 return sshbuf_putb(ssh->state->outgoing_packet, b);
2443 sshpkt_put_u8(struct ssh *ssh, u_char val)
2445 return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2449 sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2451 return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2455 sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2457 return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2461 sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2463 return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2467 sshpkt_put_cstring(struct ssh *ssh, const void *v)
2469 return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2473 sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2475 return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2479 #ifdef OPENSSL_HAS_ECC
2481 sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2483 return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2485 #endif /* OPENSSL_HAS_ECC */
2489 sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2491 return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2493 #endif /* WITH_OPENSSL */
2495 /* fetch data from the incoming packet */
2498 sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2500 return sshbuf_get(ssh->state->incoming_packet, valp, len);
2504 sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2506 return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2510 sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2512 return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2516 sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2518 return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2522 sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2524 return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2528 sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2530 return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2534 sshpkt_peek_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2536 return sshbuf_peek_string_direct(ssh->state->incoming_packet, valp, lenp);
2540 sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2542 return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2546 #ifdef OPENSSL_HAS_ECC
2548 sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2550 return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2552 #endif /* OPENSSL_HAS_ECC */
2556 sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2558 return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2560 #endif /* WITH_OPENSSL */
2563 sshpkt_get_end(struct ssh *ssh)
2565 if (sshbuf_len(ssh->state->incoming_packet) > 0)
2566 return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2571 sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2574 *lenp = sshbuf_len(ssh->state->incoming_packet);
2575 return sshbuf_ptr(ssh->state->incoming_packet);
2578 /* start a new packet */
2581 sshpkt_start(struct ssh *ssh, u_char type)
2583 u_char buf[6]; /* u32 packet length, u8 pad len, u8 type */
2585 DBG(debug("packet_start[%d]", type));
2586 memset(buf, 0, sizeof(buf));
2587 buf[sizeof(buf) - 1] = type;
2588 sshbuf_reset(ssh->state->outgoing_packet);
2589 return sshbuf_put(ssh->state->outgoing_packet, buf, sizeof(buf));
2593 ssh_packet_send_mux(struct ssh *ssh)
2595 struct session_state *state = ssh->state;
2601 return SSH_ERR_INTERNAL_ERROR;
2602 len = sshbuf_len(state->outgoing_packet);
2604 return SSH_ERR_INTERNAL_ERROR;
2605 cp = sshbuf_mutable_ptr(state->outgoing_packet);
2607 if (ssh_packet_log_type(type))
2608 debug3("%s: type %u", __func__, type);
2609 /* drop everything, but the connection protocol */
2610 if (type >= SSH2_MSG_CONNECTION_MIN &&
2611 type <= SSH2_MSG_CONNECTION_MAX) {
2612 POKE_U32(cp, len - 4);
2613 if ((r = sshbuf_putb(state->output,
2614 state->outgoing_packet)) != 0)
2616 /* sshbuf_dump(state->output, stderr); */
2618 sshbuf_reset(state->outgoing_packet);
2623 * 9.2. Ignored Data Message
2625 * byte SSH_MSG_IGNORE
2628 * All implementations MUST understand (and ignore) this message at any
2629 * time (after receiving the protocol version). No implementation is
2630 * required to send them. This message can be used as an additional
2631 * protection measure against advanced traffic analysis techniques.
2634 sshpkt_msg_ignore(struct ssh *ssh, u_int nbytes)
2640 if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
2641 (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2643 for (i = 0; i < nbytes; i++) {
2646 if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2656 sshpkt_send(struct ssh *ssh)
2658 if (ssh->state && ssh->state->mux)
2659 return ssh_packet_send_mux(ssh);
2660 return ssh_packet_send2(ssh);
2664 sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2670 va_start(args, fmt);
2671 vsnprintf(buf, sizeof(buf), fmt, args);
2674 if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2675 (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2676 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2677 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2678 (r = sshpkt_send(ssh)) != 0)
2683 /* roundup current message to pad bytes */
2685 sshpkt_add_padding(struct ssh *ssh, u_char pad)
2687 ssh->state->extra_pad = pad;