1 /* $OpenBSD: packet.c,v 1.277 2018/07/16 03:09:13 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>
66 * Explicitly include OpenSSL before zlib as some versions of OpenSSL have
67 * "free_func" in their headers, which zlib typedefs.
70 # include <openssl/bn.h>
71 # include <openssl/evp.h>
72 # ifdef OPENSSL_HAS_ECC
73 # include <openssl/ec.h>
96 #include "blacklist_client.h"
104 #define PACKET_MAX_SIZE (256 * 1024)
106 struct packet_state {
114 TAILQ_ENTRY(packet) next;
116 struct sshbuf *payload;
119 struct session_state {
121 * This variable contains the file descriptors used for
122 * communicating with the other side. connection_in is used for
123 * reading; connection_out for writing. These can be the same
124 * descriptor, in which case it is assumed to be a socket.
129 /* Protocol flags for the remote side. */
130 u_int remote_protocol_flags;
132 /* Encryption context for receiving data. Only used for decryption. */
133 struct sshcipher_ctx *receive_context;
135 /* Encryption context for sending data. Only used for encryption. */
136 struct sshcipher_ctx *send_context;
138 /* Buffer for raw input data from the socket. */
139 struct sshbuf *input;
141 /* Buffer for raw output data going to the socket. */
142 struct sshbuf *output;
144 /* Buffer for the partial outgoing packet being constructed. */
145 struct sshbuf *outgoing_packet;
147 /* Buffer for the incoming packet currently being processed. */
148 struct sshbuf *incoming_packet;
150 /* Scratch buffer for packet compression/decompression. */
151 struct sshbuf *compression_buffer;
153 /* Incoming/outgoing compression dictionaries */
154 z_stream compression_in_stream;
155 z_stream compression_out_stream;
156 int compression_in_started;
157 int compression_out_started;
158 int compression_in_failures;
159 int compression_out_failures;
161 /* default maximum packet size */
162 u_int max_packet_size;
164 /* Flag indicating whether this module has been initialized. */
167 /* Set to true if the connection is interactive. */
168 int interactive_mode;
170 /* Set to true if we are the server side. */
173 /* Set to true if we are authenticated. */
174 int after_authentication;
176 int keep_alive_timeouts;
178 /* The maximum time that we will wait to send or receive a packet */
179 int packet_timeout_ms;
181 /* Session key information for Encryption and MAC */
182 struct newkeys *newkeys[MODE_MAX];
183 struct packet_state p_read, p_send;
185 /* Volume-based rekeying */
186 u_int64_t max_blocks_in, max_blocks_out, rekey_limit;
188 /* Time-based rekeying */
189 u_int32_t rekey_interval; /* how often in seconds */
190 time_t rekey_time; /* time of last rekeying */
192 /* roundup current message to extra_pad bytes */
195 /* XXX discard incoming data after MAC error */
196 u_int packet_discard;
197 size_t packet_discard_mac_already;
198 struct sshmac *packet_discard_mac;
200 /* Used in packet_read_poll2() */
203 /* Used in packet_send2 */
206 /* Used in ssh_packet_send_mux() */
209 /* Used in packet_set_interactive */
210 int set_interactive_called;
212 /* Used in packet_set_maxsize */
213 int set_maxsize_called;
215 /* One-off warning about weak ciphers */
216 int cipher_warning_done;
218 /* Hook for fuzzing inbound packets */
219 ssh_packet_hook_fn *hook_in;
222 TAILQ_HEAD(, packet) outgoing;
226 ssh_alloc_session_state(void)
228 struct ssh *ssh = NULL;
229 struct session_state *state = NULL;
231 if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
232 (state = calloc(1, sizeof(*state))) == NULL ||
233 (state->input = sshbuf_new()) == NULL ||
234 (state->output = sshbuf_new()) == NULL ||
235 (state->outgoing_packet = sshbuf_new()) == NULL ||
236 (state->incoming_packet = sshbuf_new()) == NULL)
238 TAILQ_INIT(&state->outgoing);
239 TAILQ_INIT(&ssh->private_keys);
240 TAILQ_INIT(&ssh->public_keys);
241 state->connection_in = -1;
242 state->connection_out = -1;
243 state->max_packet_size = 32768;
244 state->packet_timeout_ms = -1;
245 state->p_send.packets = state->p_read.packets = 0;
246 state->initialized = 1;
248 * ssh_packet_send2() needs to queue packets until
249 * we've done the initial key exchange.
256 sshbuf_free(state->input);
257 sshbuf_free(state->output);
258 sshbuf_free(state->incoming_packet);
259 sshbuf_free(state->outgoing_packet);
267 ssh_packet_set_input_hook(struct ssh *ssh, ssh_packet_hook_fn *hook, void *ctx)
269 ssh->state->hook_in = hook;
270 ssh->state->hook_in_ctx = ctx;
273 /* Returns nonzero if rekeying is in progress */
275 ssh_packet_is_rekeying(struct ssh *ssh)
277 return ssh->state->rekeying ||
278 (ssh->kex != NULL && ssh->kex->done == 0);
282 * Sets the descriptors used for communication.
285 ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
287 struct session_state *state;
288 const struct sshcipher *none = cipher_by_name("none");
292 error("%s: cannot load cipher 'none'", __func__);
296 ssh = ssh_alloc_session_state();
298 error("%s: cound not allocate state", __func__);
302 state->connection_in = fd_in;
303 state->connection_out = fd_out;
304 if ((r = cipher_init(&state->send_context, none,
305 (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
306 (r = cipher_init(&state->receive_context, none,
307 (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
308 error("%s: cipher_init failed: %s", __func__, ssh_err(r));
309 free(ssh); /* XXX need ssh_free_session_state? */
312 state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
314 * Cache the IP address of the remote connection for use in error
315 * messages that might be generated after the connection has closed.
317 (void)ssh_remote_ipaddr(ssh);
322 ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
324 struct session_state *state = ssh->state;
326 if (timeout <= 0 || count <= 0) {
327 state->packet_timeout_ms = -1;
330 if ((INT_MAX / 1000) / count < timeout)
331 state->packet_timeout_ms = INT_MAX;
333 state->packet_timeout_ms = timeout * count * 1000;
337 ssh_packet_set_mux(struct ssh *ssh)
340 ssh->state->rekeying = 0;
344 ssh_packet_get_mux(struct ssh *ssh)
346 return ssh->state->mux;
350 ssh_packet_set_log_preamble(struct ssh *ssh, const char *fmt, ...)
355 free(ssh->log_preamble);
357 ssh->log_preamble = NULL;
360 r = vasprintf(&ssh->log_preamble, fmt, args);
362 if (r < 0 || ssh->log_preamble == NULL)
363 return SSH_ERR_ALLOC_FAIL;
369 ssh_packet_stop_discard(struct ssh *ssh)
371 struct session_state *state = ssh->state;
374 if (state->packet_discard_mac) {
376 size_t dlen = PACKET_MAX_SIZE;
378 if (dlen > state->packet_discard_mac_already)
379 dlen -= state->packet_discard_mac_already;
380 memset(buf, 'a', sizeof(buf));
381 while (sshbuf_len(state->incoming_packet) < dlen)
382 if ((r = sshbuf_put(state->incoming_packet, buf,
385 (void) mac_compute(state->packet_discard_mac,
387 sshbuf_ptr(state->incoming_packet), dlen,
390 logit("Finished discarding for %.200s port %d",
391 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
392 return SSH_ERR_MAC_INVALID;
396 ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
397 struct sshmac *mac, size_t mac_already, u_int discard)
399 struct session_state *state = ssh->state;
402 if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
403 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
405 return SSH_ERR_MAC_INVALID;
408 * Record number of bytes over which the mac has already
409 * been computed in order to minimize timing attacks.
411 if (mac && mac->enabled) {
412 state->packet_discard_mac = mac;
413 state->packet_discard_mac_already = mac_already;
415 if (sshbuf_len(state->input) >= discard)
416 return ssh_packet_stop_discard(ssh);
417 state->packet_discard = discard - sshbuf_len(state->input);
421 /* Returns 1 if remote host is connected via socket, 0 if not. */
424 ssh_packet_connection_is_on_socket(struct ssh *ssh)
426 struct session_state *state;
427 struct sockaddr_storage from, to;
428 socklen_t fromlen, tolen;
430 if (ssh == NULL || ssh->state == NULL)
434 if (state->connection_in == -1 || state->connection_out == -1)
436 /* filedescriptors in and out are the same, so it's a socket */
437 if (state->connection_in == state->connection_out)
439 fromlen = sizeof(from);
440 memset(&from, 0, sizeof(from));
441 if (getpeername(state->connection_in, (struct sockaddr *)&from,
445 memset(&to, 0, sizeof(to));
446 if (getpeername(state->connection_out, (struct sockaddr *)&to,
449 if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
451 if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
457 ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
460 *ibytes = ssh->state->p_read.bytes;
462 *obytes = ssh->state->p_send.bytes;
466 ssh_packet_connection_af(struct ssh *ssh)
468 struct sockaddr_storage to;
469 socklen_t tolen = sizeof(to);
471 memset(&to, 0, sizeof(to));
472 if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
476 if (to.ss_family == AF_INET6 &&
477 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr))
483 /* Sets the connection into non-blocking mode. */
486 ssh_packet_set_nonblocking(struct ssh *ssh)
488 /* Set the socket into non-blocking mode. */
489 set_nonblock(ssh->state->connection_in);
491 if (ssh->state->connection_out != ssh->state->connection_in)
492 set_nonblock(ssh->state->connection_out);
495 /* Returns the socket used for reading. */
498 ssh_packet_get_connection_in(struct ssh *ssh)
500 return ssh->state->connection_in;
503 /* Returns the descriptor used for writing. */
506 ssh_packet_get_connection_out(struct ssh *ssh)
508 return ssh->state->connection_out;
512 * Returns the IP-address of the remote host as a string. The returned
513 * string must not be freed.
517 ssh_remote_ipaddr(struct ssh *ssh)
521 /* Check whether we have cached the ipaddr. */
522 if (ssh->remote_ipaddr == NULL) {
523 if (ssh_packet_connection_is_on_socket(ssh)) {
524 sock = ssh->state->connection_in;
525 ssh->remote_ipaddr = get_peer_ipaddr(sock);
526 ssh->remote_port = get_peer_port(sock);
527 ssh->local_ipaddr = get_local_ipaddr(sock);
528 ssh->local_port = get_local_port(sock);
530 ssh->remote_ipaddr = strdup("UNKNOWN");
531 ssh->remote_port = 65535;
532 ssh->local_ipaddr = strdup("UNKNOWN");
533 ssh->local_port = 65535;
536 return ssh->remote_ipaddr;
539 /* Returns the port number of the remote host. */
542 ssh_remote_port(struct ssh *ssh)
544 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
545 return ssh->remote_port;
549 * Returns the IP-address of the local host as a string. The returned
550 * string must not be freed.
554 ssh_local_ipaddr(struct ssh *ssh)
556 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
557 return ssh->local_ipaddr;
560 /* Returns the port number of the local host. */
563 ssh_local_port(struct ssh *ssh)
565 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
566 return ssh->local_port;
569 /* Returns the routing domain of the input socket, or NULL if unavailable */
571 ssh_packet_rdomain_in(struct ssh *ssh)
573 if (ssh->rdomain_in != NULL)
574 return ssh->rdomain_in;
575 if (!ssh_packet_connection_is_on_socket(ssh))
577 ssh->rdomain_in = get_rdomain(ssh->state->connection_in);
578 return ssh->rdomain_in;
581 /* Closes the connection and clears and frees internal data structures. */
584 ssh_packet_close_internal(struct ssh *ssh, int do_close)
586 struct session_state *state = ssh->state;
589 if (!state->initialized)
591 state->initialized = 0;
593 if (state->connection_in == state->connection_out) {
594 close(state->connection_out);
596 close(state->connection_in);
597 close(state->connection_out);
600 sshbuf_free(state->input);
601 sshbuf_free(state->output);
602 sshbuf_free(state->outgoing_packet);
603 sshbuf_free(state->incoming_packet);
604 for (mode = 0; mode < MODE_MAX; mode++) {
605 kex_free_newkeys(state->newkeys[mode]); /* current keys */
606 state->newkeys[mode] = NULL;
607 ssh_clear_newkeys(ssh, mode); /* next keys */
609 /* compression state is in shared mem, so we can only release it once */
610 if (do_close && state->compression_buffer) {
611 sshbuf_free(state->compression_buffer);
612 if (state->compression_out_started) {
613 z_streamp stream = &state->compression_out_stream;
614 debug("compress outgoing: "
615 "raw data %llu, compressed %llu, factor %.2f",
616 (unsigned long long)stream->total_in,
617 (unsigned long long)stream->total_out,
618 stream->total_in == 0 ? 0.0 :
619 (double) stream->total_out / stream->total_in);
620 if (state->compression_out_failures == 0)
623 if (state->compression_in_started) {
624 z_streamp stream = &state->compression_in_stream;
625 debug("compress incoming: "
626 "raw data %llu, compressed %llu, factor %.2f",
627 (unsigned long long)stream->total_out,
628 (unsigned long long)stream->total_in,
629 stream->total_out == 0 ? 0.0 :
630 (double) stream->total_in / stream->total_out);
631 if (state->compression_in_failures == 0)
635 cipher_free(state->send_context);
636 cipher_free(state->receive_context);
637 state->send_context = state->receive_context = NULL;
639 free(ssh->local_ipaddr);
640 ssh->local_ipaddr = NULL;
641 free(ssh->remote_ipaddr);
642 ssh->remote_ipaddr = NULL;
649 ssh_packet_close(struct ssh *ssh)
651 ssh_packet_close_internal(ssh, 1);
655 ssh_packet_clear_keys(struct ssh *ssh)
657 ssh_packet_close_internal(ssh, 0);
660 /* Sets remote side protocol flags. */
663 ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
665 ssh->state->remote_protocol_flags = protocol_flags;
668 /* Returns the remote protocol flags set earlier by the above function. */
671 ssh_packet_get_protocol_flags(struct ssh *ssh)
673 return ssh->state->remote_protocol_flags;
677 * Starts packet compression from the next packet on in both directions.
678 * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
682 ssh_packet_init_compression(struct ssh *ssh)
684 if (!ssh->state->compression_buffer &&
685 ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
686 return SSH_ERR_ALLOC_FAIL;
691 start_compression_out(struct ssh *ssh, int level)
693 if (level < 1 || level > 9)
694 return SSH_ERR_INVALID_ARGUMENT;
695 debug("Enabling compression at level %d.", level);
696 if (ssh->state->compression_out_started == 1)
697 deflateEnd(&ssh->state->compression_out_stream);
698 switch (deflateInit(&ssh->state->compression_out_stream, level)) {
700 ssh->state->compression_out_started = 1;
703 return SSH_ERR_ALLOC_FAIL;
705 return SSH_ERR_INTERNAL_ERROR;
711 start_compression_in(struct ssh *ssh)
713 if (ssh->state->compression_in_started == 1)
714 inflateEnd(&ssh->state->compression_in_stream);
715 switch (inflateInit(&ssh->state->compression_in_stream)) {
717 ssh->state->compression_in_started = 1;
720 return SSH_ERR_ALLOC_FAIL;
722 return SSH_ERR_INTERNAL_ERROR;
727 /* XXX remove need for separate compression buffer */
729 compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
734 if (ssh->state->compression_out_started != 1)
735 return SSH_ERR_INTERNAL_ERROR;
737 /* This case is not handled below. */
738 if (sshbuf_len(in) == 0)
741 /* Input is the contents of the input buffer. */
742 if ((ssh->state->compression_out_stream.next_in =
743 sshbuf_mutable_ptr(in)) == NULL)
744 return SSH_ERR_INTERNAL_ERROR;
745 ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
747 /* Loop compressing until deflate() returns with avail_out != 0. */
749 /* Set up fixed-size output buffer. */
750 ssh->state->compression_out_stream.next_out = buf;
751 ssh->state->compression_out_stream.avail_out = sizeof(buf);
753 /* Compress as much data into the buffer as possible. */
754 status = deflate(&ssh->state->compression_out_stream,
758 return SSH_ERR_ALLOC_FAIL;
760 /* Append compressed data to output_buffer. */
761 if ((r = sshbuf_put(out, buf, sizeof(buf) -
762 ssh->state->compression_out_stream.avail_out)) != 0)
767 ssh->state->compression_out_failures++;
768 return SSH_ERR_INVALID_FORMAT;
770 } while (ssh->state->compression_out_stream.avail_out == 0);
775 uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
780 if (ssh->state->compression_in_started != 1)
781 return SSH_ERR_INTERNAL_ERROR;
783 if ((ssh->state->compression_in_stream.next_in =
784 sshbuf_mutable_ptr(in)) == NULL)
785 return SSH_ERR_INTERNAL_ERROR;
786 ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
789 /* Set up fixed-size output buffer. */
790 ssh->state->compression_in_stream.next_out = buf;
791 ssh->state->compression_in_stream.avail_out = sizeof(buf);
793 status = inflate(&ssh->state->compression_in_stream,
797 if ((r = sshbuf_put(out, buf, sizeof(buf) -
798 ssh->state->compression_in_stream.avail_out)) != 0)
803 * Comments in zlib.h say that we should keep calling
804 * inflate() until we get an error. This appears to
805 * be the error that we get.
809 return SSH_ERR_INVALID_FORMAT;
811 return SSH_ERR_ALLOC_FAIL;
814 ssh->state->compression_in_failures++;
815 return SSH_ERR_INTERNAL_ERROR;
822 ssh_clear_newkeys(struct ssh *ssh, int mode)
824 if (ssh->kex && ssh->kex->newkeys[mode]) {
825 kex_free_newkeys(ssh->kex->newkeys[mode]);
826 ssh->kex->newkeys[mode] = NULL;
831 ssh_set_newkeys(struct ssh *ssh, int mode)
833 struct session_state *state = ssh->state;
836 struct sshcomp *comp;
837 struct sshcipher_ctx **ccp;
838 struct packet_state *ps;
839 u_int64_t *max_blocks;
843 debug2("set_newkeys: mode %d", mode);
845 if (mode == MODE_OUT) {
846 ccp = &state->send_context;
847 crypt_type = CIPHER_ENCRYPT;
849 max_blocks = &state->max_blocks_out;
851 ccp = &state->receive_context;
852 crypt_type = CIPHER_DECRYPT;
854 max_blocks = &state->max_blocks_in;
856 if (state->newkeys[mode] != NULL) {
857 debug("set_newkeys: rekeying, input %llu bytes %llu blocks, "
858 "output %llu bytes %llu blocks",
859 (unsigned long long)state->p_read.bytes,
860 (unsigned long long)state->p_read.blocks,
861 (unsigned long long)state->p_send.bytes,
862 (unsigned long long)state->p_send.blocks);
865 kex_free_newkeys(state->newkeys[mode]);
866 state->newkeys[mode] = NULL;
868 /* note that both bytes and the seqnr are not reset */
869 ps->packets = ps->blocks = 0;
870 /* move newkeys from kex to state */
871 if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
872 return SSH_ERR_INTERNAL_ERROR;
873 ssh->kex->newkeys[mode] = NULL;
874 enc = &state->newkeys[mode]->enc;
875 mac = &state->newkeys[mode]->mac;
876 comp = &state->newkeys[mode]->comp;
877 if (cipher_authlen(enc->cipher) == 0) {
878 if ((r = mac_init(mac)) != 0)
882 DBG(debug("cipher_init_context: %d", mode));
883 if ((r = cipher_init(ccp, enc->cipher, enc->key, enc->key_len,
884 enc->iv, enc->iv_len, crypt_type)) != 0)
886 if (!state->cipher_warning_done &&
887 (wmsg = cipher_warning_message(*ccp)) != NULL) {
888 error("Warning: %s", wmsg);
889 state->cipher_warning_done = 1;
891 /* Deleting the keys does not gain extra security */
892 /* explicit_bzero(enc->iv, enc->block_size);
893 explicit_bzero(enc->key, enc->key_len);
894 explicit_bzero(mac->key, mac->key_len); */
895 if ((comp->type == COMP_ZLIB ||
896 (comp->type == COMP_DELAYED &&
897 state->after_authentication)) && comp->enabled == 0) {
898 if ((r = ssh_packet_init_compression(ssh)) < 0)
900 if (mode == MODE_OUT) {
901 if ((r = start_compression_out(ssh, 6)) != 0)
904 if ((r = start_compression_in(ssh)) != 0)
910 * The 2^(blocksize*2) limit is too expensive for 3DES,
911 * so enforce a 1GB limit for small blocksizes.
912 * See RFC4344 section 3.2.
914 if (enc->block_size >= 16)
915 *max_blocks = (u_int64_t)1 << (enc->block_size*2);
917 *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
918 if (state->rekey_limit)
919 *max_blocks = MINIMUM(*max_blocks,
920 state->rekey_limit / enc->block_size);
921 debug("rekey after %llu blocks", (unsigned long long)*max_blocks);
925 #define MAX_PACKETS (1U<<31)
927 ssh_packet_need_rekeying(struct ssh *ssh, u_int outbound_packet_len)
929 struct session_state *state = ssh->state;
930 u_int32_t out_blocks;
932 /* XXX client can't cope with rekeying pre-auth */
933 if (!state->after_authentication)
936 /* Haven't keyed yet or KEX in progress. */
937 if (ssh->kex == NULL || ssh_packet_is_rekeying(ssh))
940 /* Peer can't rekey */
941 if (ssh->compat & SSH_BUG_NOREKEY)
945 * Permit one packet in or out per rekey - this allows us to
946 * make progress when rekey limits are very small.
948 if (state->p_send.packets == 0 && state->p_read.packets == 0)
951 /* Time-based rekeying */
952 if (state->rekey_interval != 0 &&
953 (int64_t)state->rekey_time + state->rekey_interval <= monotime())
957 * Always rekey when MAX_PACKETS sent in either direction
958 * As per RFC4344 section 3.1 we do this after 2^31 packets.
960 if (state->p_send.packets > MAX_PACKETS ||
961 state->p_read.packets > MAX_PACKETS)
964 /* Rekey after (cipher-specific) maximum blocks */
965 out_blocks = ROUNDUP(outbound_packet_len,
966 state->newkeys[MODE_OUT]->enc.block_size);
967 return (state->max_blocks_out &&
968 (state->p_send.blocks + out_blocks > state->max_blocks_out)) ||
969 (state->max_blocks_in &&
970 (state->p_read.blocks > state->max_blocks_in));
974 * Delayed compression for SSH2 is enabled after authentication:
975 * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
976 * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
979 ssh_packet_enable_delayed_compress(struct ssh *ssh)
981 struct session_state *state = ssh->state;
982 struct sshcomp *comp = NULL;
986 * Remember that we are past the authentication step, so rekeying
987 * with COMP_DELAYED will turn on compression immediately.
989 state->after_authentication = 1;
990 for (mode = 0; mode < MODE_MAX; mode++) {
991 /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
992 if (state->newkeys[mode] == NULL)
994 comp = &state->newkeys[mode]->comp;
995 if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
996 if ((r = ssh_packet_init_compression(ssh)) != 0)
998 if (mode == MODE_OUT) {
999 if ((r = start_compression_out(ssh, 6)) != 0)
1002 if ((r = start_compression_in(ssh)) != 0)
1011 /* Used to mute debug logging for noisy packet types */
1013 ssh_packet_log_type(u_char type)
1016 case SSH2_MSG_CHANNEL_DATA:
1017 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1018 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1026 * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1029 ssh_packet_send2_wrapped(struct ssh *ssh)
1031 struct session_state *state = ssh->state;
1032 u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1033 u_char tmp, padlen, pad = 0;
1034 u_int authlen = 0, aadlen = 0;
1036 struct sshenc *enc = NULL;
1037 struct sshmac *mac = NULL;
1038 struct sshcomp *comp = NULL;
1041 if (state->newkeys[MODE_OUT] != NULL) {
1042 enc = &state->newkeys[MODE_OUT]->enc;
1043 mac = &state->newkeys[MODE_OUT]->mac;
1044 comp = &state->newkeys[MODE_OUT]->comp;
1045 /* disable mac for authenticated encryption */
1046 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1049 block_size = enc ? enc->block_size : 8;
1050 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1052 type = (sshbuf_ptr(state->outgoing_packet))[5];
1053 if (ssh_packet_log_type(type))
1054 debug3("send packet: type %u", type);
1056 fprintf(stderr, "plain: ");
1057 sshbuf_dump(state->outgoing_packet, stderr);
1060 if (comp && comp->enabled) {
1061 len = sshbuf_len(state->outgoing_packet);
1062 /* skip header, compress only payload */
1063 if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1065 sshbuf_reset(state->compression_buffer);
1066 if ((r = compress_buffer(ssh, state->outgoing_packet,
1067 state->compression_buffer)) != 0)
1069 sshbuf_reset(state->outgoing_packet);
1070 if ((r = sshbuf_put(state->outgoing_packet,
1071 "\0\0\0\0\0", 5)) != 0 ||
1072 (r = sshbuf_putb(state->outgoing_packet,
1073 state->compression_buffer)) != 0)
1075 DBG(debug("compression: raw %d compressed %zd", len,
1076 sshbuf_len(state->outgoing_packet)));
1079 /* sizeof (packet_len + pad_len + payload) */
1080 len = sshbuf_len(state->outgoing_packet);
1083 * calc size of padding, alloc space, get random data,
1084 * minimum padding is 4 bytes
1086 len -= aadlen; /* packet length is not encrypted for EtM modes */
1087 padlen = block_size - (len % block_size);
1089 padlen += block_size;
1090 if (state->extra_pad) {
1091 tmp = state->extra_pad;
1093 ROUNDUP(state->extra_pad, block_size);
1094 /* check if roundup overflowed */
1095 if (state->extra_pad < tmp)
1096 return SSH_ERR_INVALID_ARGUMENT;
1097 tmp = (len + padlen) % state->extra_pad;
1098 /* Check whether pad calculation below will underflow */
1099 if (tmp > state->extra_pad)
1100 return SSH_ERR_INVALID_ARGUMENT;
1101 pad = state->extra_pad - tmp;
1102 DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1103 __func__, pad, len, padlen, state->extra_pad));
1106 /* Check whether padlen calculation overflowed */
1108 return SSH_ERR_INVALID_ARGUMENT; /* overflow */
1109 state->extra_pad = 0;
1111 if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1113 if (enc && !cipher_ctx_is_plaintext(state->send_context)) {
1114 /* random padding */
1115 arc4random_buf(cp, padlen);
1118 explicit_bzero(cp, padlen);
1120 /* sizeof (packet_len + pad_len + payload + padding) */
1121 len = sshbuf_len(state->outgoing_packet);
1122 cp = sshbuf_mutable_ptr(state->outgoing_packet);
1124 r = SSH_ERR_INTERNAL_ERROR;
1127 /* packet_length includes payload, padding and padding length field */
1128 POKE_U32(cp, len - 4);
1130 DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1131 len, padlen, aadlen));
1133 /* compute MAC over seqnr and packet(length fields, payload, padding) */
1134 if (mac && mac->enabled && !mac->etm) {
1135 if ((r = mac_compute(mac, state->p_send.seqnr,
1136 sshbuf_ptr(state->outgoing_packet), len,
1137 macbuf, sizeof(macbuf))) != 0)
1139 DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1141 /* encrypt packet and append to output buffer. */
1142 if ((r = sshbuf_reserve(state->output,
1143 sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1145 if ((r = cipher_crypt(state->send_context, state->p_send.seqnr, cp,
1146 sshbuf_ptr(state->outgoing_packet),
1147 len - aadlen, aadlen, authlen)) != 0)
1149 /* append unencrypted MAC */
1150 if (mac && mac->enabled) {
1152 /* EtM: compute mac over aadlen + cipher text */
1153 if ((r = mac_compute(mac, state->p_send.seqnr,
1154 cp, len, macbuf, sizeof(macbuf))) != 0)
1156 DBG(debug("done calc MAC(EtM) out #%d",
1157 state->p_send.seqnr));
1159 if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1163 fprintf(stderr, "encrypted: ");
1164 sshbuf_dump(state->output, stderr);
1166 /* increment sequence number for outgoing packets */
1167 if (++state->p_send.seqnr == 0)
1168 logit("outgoing seqnr wraps around");
1169 if (++state->p_send.packets == 0)
1170 if (!(ssh->compat & SSH_BUG_NOREKEY))
1171 return SSH_ERR_NEED_REKEY;
1172 state->p_send.blocks += len / block_size;
1173 state->p_send.bytes += len;
1174 sshbuf_reset(state->outgoing_packet);
1176 if (type == SSH2_MSG_NEWKEYS)
1177 r = ssh_set_newkeys(ssh, MODE_OUT);
1178 else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1179 r = ssh_packet_enable_delayed_compress(ssh);
1186 /* returns non-zero if the specified packet type is usec by KEX */
1188 ssh_packet_type_is_kex(u_char type)
1191 type >= SSH2_MSG_TRANSPORT_MIN &&
1192 type <= SSH2_MSG_TRANSPORT_MAX &&
1193 type != SSH2_MSG_SERVICE_REQUEST &&
1194 type != SSH2_MSG_SERVICE_ACCEPT &&
1195 type != SSH2_MSG_EXT_INFO;
1199 ssh_packet_send2(struct ssh *ssh)
1201 struct session_state *state = ssh->state;
1206 if (sshbuf_len(state->outgoing_packet) < 6)
1207 return SSH_ERR_INTERNAL_ERROR;
1208 type = sshbuf_ptr(state->outgoing_packet)[5];
1209 need_rekey = !ssh_packet_type_is_kex(type) &&
1210 ssh_packet_need_rekeying(ssh, sshbuf_len(state->outgoing_packet));
1213 * During rekeying we can only send key exchange messages.
1214 * Queue everything else.
1216 if ((need_rekey || state->rekeying) && !ssh_packet_type_is_kex(type)) {
1218 debug3("%s: rekex triggered", __func__);
1219 debug("enqueue packet: %u", type);
1220 p = calloc(1, sizeof(*p));
1222 return SSH_ERR_ALLOC_FAIL;
1224 p->payload = state->outgoing_packet;
1225 TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1226 state->outgoing_packet = sshbuf_new();
1227 if (state->outgoing_packet == NULL)
1228 return SSH_ERR_ALLOC_FAIL;
1231 * This packet triggered a rekey, so send the
1233 * NB. reenters this function via kex_start_rekex().
1235 return kex_start_rekex(ssh);
1240 /* rekeying starts with sending KEXINIT */
1241 if (type == SSH2_MSG_KEXINIT)
1242 state->rekeying = 1;
1244 if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1247 /* after a NEWKEYS message we can send the complete queue */
1248 if (type == SSH2_MSG_NEWKEYS) {
1249 state->rekeying = 0;
1250 state->rekey_time = monotime();
1251 while ((p = TAILQ_FIRST(&state->outgoing))) {
1254 * If this packet triggers a rekex, then skip the
1255 * remaining packets in the queue for now.
1256 * NB. re-enters this function via kex_start_rekex.
1258 if (ssh_packet_need_rekeying(ssh,
1259 sshbuf_len(p->payload))) {
1260 debug3("%s: queued packet triggered rekex",
1262 return kex_start_rekex(ssh);
1264 debug("dequeue packet: %u", type);
1265 sshbuf_free(state->outgoing_packet);
1266 state->outgoing_packet = p->payload;
1267 TAILQ_REMOVE(&state->outgoing, p, next);
1268 memset(p, 0, sizeof(*p));
1270 if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1278 * Waits until a packet has been received, and returns its type. Note that
1279 * no other data is processed until this returns, so this function should not
1280 * be used during the interactive session.
1284 ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1286 struct session_state *state = ssh->state;
1287 int len, r, ms_remain;
1290 struct timeval timeout, start, *timeoutp = NULL;
1292 DBG(debug("packet_read()"));
1294 setp = calloc(howmany(state->connection_in + 1,
1295 NFDBITS), sizeof(fd_mask));
1297 return SSH_ERR_ALLOC_FAIL;
1300 * Since we are blocking, ensure that all written packets have
1303 if ((r = ssh_packet_write_wait(ssh)) != 0)
1306 /* Stay in the loop until we have received a complete packet. */
1308 /* Try to read a packet from the buffer. */
1309 r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1312 /* If we got a packet, return it. */
1313 if (*typep != SSH_MSG_NONE)
1316 * Otherwise, wait for some data to arrive, add it to the
1317 * buffer, and try again.
1319 memset(setp, 0, howmany(state->connection_in + 1,
1320 NFDBITS) * sizeof(fd_mask));
1321 FD_SET(state->connection_in, setp);
1323 if (state->packet_timeout_ms > 0) {
1324 ms_remain = state->packet_timeout_ms;
1325 timeoutp = &timeout;
1327 /* Wait for some data to arrive. */
1329 if (state->packet_timeout_ms != -1) {
1330 ms_to_timeval(&timeout, ms_remain);
1331 monotime_tv(&start);
1333 if ((r = select(state->connection_in + 1, setp,
1334 NULL, NULL, timeoutp)) >= 0)
1336 if (errno != EAGAIN && errno != EINTR &&
1337 errno != EWOULDBLOCK) {
1338 r = SSH_ERR_SYSTEM_ERROR;
1341 if (state->packet_timeout_ms == -1)
1343 ms_subtract_diff(&start, &ms_remain);
1344 if (ms_remain <= 0) {
1350 r = SSH_ERR_CONN_TIMEOUT;
1353 /* Read data from the socket. */
1354 len = read(state->connection_in, buf, sizeof(buf));
1356 r = SSH_ERR_CONN_CLOSED;
1360 r = SSH_ERR_SYSTEM_ERROR;
1364 /* Append it to the buffer. */
1365 if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1374 ssh_packet_read(struct ssh *ssh)
1379 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1380 fatal("%s: %s", __func__, ssh_err(r));
1385 * Waits until a packet has been received, verifies that its type matches
1386 * that given, and gives a fatal error and exits if there is a mismatch.
1390 ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1395 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1397 if (type != expected_type) {
1398 if ((r = sshpkt_disconnect(ssh,
1399 "Protocol error: expected packet type %d, got %d",
1400 expected_type, type)) != 0)
1402 return SSH_ERR_PROTOCOL_ERROR;
1408 ssh_packet_read_poll2_mux(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1410 struct session_state *state = ssh->state;
1416 return SSH_ERR_INTERNAL_ERROR;
1417 *typep = SSH_MSG_NONE;
1418 cp = sshbuf_ptr(state->input);
1419 if (state->packlen == 0) {
1420 if (sshbuf_len(state->input) < 4 + 1)
1421 return 0; /* packet is incomplete */
1422 state->packlen = PEEK_U32(cp);
1423 if (state->packlen < 4 + 1 ||
1424 state->packlen > PACKET_MAX_SIZE)
1425 return SSH_ERR_MESSAGE_INCOMPLETE;
1427 need = state->packlen + 4;
1428 if (sshbuf_len(state->input) < need)
1429 return 0; /* packet is incomplete */
1430 sshbuf_reset(state->incoming_packet);
1431 if ((r = sshbuf_put(state->incoming_packet, cp + 4,
1432 state->packlen)) != 0 ||
1433 (r = sshbuf_consume(state->input, need)) != 0 ||
1434 (r = sshbuf_get_u8(state->incoming_packet, NULL)) != 0 ||
1435 (r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1437 if (ssh_packet_log_type(*typep))
1438 debug3("%s: type %u", __func__, *typep);
1439 /* sshbuf_dump(state->incoming_packet, stderr); */
1440 /* reset for next packet */
1446 ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1448 struct session_state *state = ssh->state;
1451 u_int maclen, aadlen = 0, authlen = 0, block_size;
1452 struct sshenc *enc = NULL;
1453 struct sshmac *mac = NULL;
1454 struct sshcomp *comp = NULL;
1458 return ssh_packet_read_poll2_mux(ssh, typep, seqnr_p);
1460 *typep = SSH_MSG_NONE;
1462 if (state->packet_discard)
1465 if (state->newkeys[MODE_IN] != NULL) {
1466 enc = &state->newkeys[MODE_IN]->enc;
1467 mac = &state->newkeys[MODE_IN]->mac;
1468 comp = &state->newkeys[MODE_IN]->comp;
1469 /* disable mac for authenticated encryption */
1470 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1473 maclen = mac && mac->enabled ? mac->mac_len : 0;
1474 block_size = enc ? enc->block_size : 8;
1475 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1477 if (aadlen && state->packlen == 0) {
1478 if (cipher_get_length(state->receive_context,
1479 &state->packlen, state->p_read.seqnr,
1480 sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1482 if (state->packlen < 1 + 4 ||
1483 state->packlen > PACKET_MAX_SIZE) {
1485 sshbuf_dump(state->input, stderr);
1487 logit("Bad packet length %u.", state->packlen);
1488 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1490 return SSH_ERR_CONN_CORRUPT;
1492 sshbuf_reset(state->incoming_packet);
1493 } else if (state->packlen == 0) {
1495 * check if input size is less than the cipher block size,
1496 * decrypt first block and extract length of incoming packet
1498 if (sshbuf_len(state->input) < block_size)
1500 sshbuf_reset(state->incoming_packet);
1501 if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1504 if ((r = cipher_crypt(state->receive_context,
1505 state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1506 block_size, 0, 0)) != 0)
1508 state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1509 if (state->packlen < 1 + 4 ||
1510 state->packlen > PACKET_MAX_SIZE) {
1512 fprintf(stderr, "input: \n");
1513 sshbuf_dump(state->input, stderr);
1514 fprintf(stderr, "incoming_packet: \n");
1515 sshbuf_dump(state->incoming_packet, stderr);
1517 logit("Bad packet length %u.", state->packlen);
1518 return ssh_packet_start_discard(ssh, enc, mac, 0,
1521 if ((r = sshbuf_consume(state->input, block_size)) != 0)
1524 DBG(debug("input: packet len %u", state->packlen+4));
1527 /* only the payload is encrypted */
1528 need = state->packlen;
1531 * the payload size and the payload are encrypted, but we
1532 * have a partial packet of block_size bytes
1534 need = 4 + state->packlen - block_size;
1536 DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1537 " aadlen %d", block_size, need, maclen, authlen, aadlen));
1538 if (need % block_size != 0) {
1539 logit("padding error: need %d block %d mod %d",
1540 need, block_size, need % block_size);
1541 return ssh_packet_start_discard(ssh, enc, mac, 0,
1542 PACKET_MAX_SIZE - block_size);
1545 * check if the entire packet has been received and
1546 * decrypt into incoming_packet:
1547 * 'aadlen' bytes are unencrypted, but authenticated.
1548 * 'need' bytes are encrypted, followed by either
1549 * 'authlen' bytes of authentication tag or
1550 * 'maclen' bytes of message authentication code.
1552 if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1553 return 0; /* packet is incomplete */
1555 fprintf(stderr, "read_poll enc/full: ");
1556 sshbuf_dump(state->input, stderr);
1558 /* EtM: check mac over encrypted input */
1559 if (mac && mac->enabled && mac->etm) {
1560 if ((r = mac_check(mac, state->p_read.seqnr,
1561 sshbuf_ptr(state->input), aadlen + need,
1562 sshbuf_ptr(state->input) + aadlen + need + authlen,
1564 if (r == SSH_ERR_MAC_INVALID)
1565 logit("Corrupted MAC on input.");
1569 if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1572 if ((r = cipher_crypt(state->receive_context, state->p_read.seqnr, cp,
1573 sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1575 if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1577 if (mac && mac->enabled) {
1578 /* Not EtM: check MAC over cleartext */
1579 if (!mac->etm && (r = mac_check(mac, state->p_read.seqnr,
1580 sshbuf_ptr(state->incoming_packet),
1581 sshbuf_len(state->incoming_packet),
1582 sshbuf_ptr(state->input), maclen)) != 0) {
1583 if (r != SSH_ERR_MAC_INVALID)
1585 logit("Corrupted MAC on input.");
1586 if (need + block_size > PACKET_MAX_SIZE)
1587 return SSH_ERR_INTERNAL_ERROR;
1588 return ssh_packet_start_discard(ssh, enc, mac,
1589 sshbuf_len(state->incoming_packet),
1590 PACKET_MAX_SIZE - need - block_size);
1592 /* Remove MAC from input buffer */
1593 DBG(debug("MAC #%d ok", state->p_read.seqnr));
1594 if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1597 if (seqnr_p != NULL)
1598 *seqnr_p = state->p_read.seqnr;
1599 if (++state->p_read.seqnr == 0)
1600 logit("incoming seqnr wraps around");
1601 if (++state->p_read.packets == 0)
1602 if (!(ssh->compat & SSH_BUG_NOREKEY))
1603 return SSH_ERR_NEED_REKEY;
1604 state->p_read.blocks += (state->packlen + 4) / block_size;
1605 state->p_read.bytes += state->packlen + 4;
1608 padlen = sshbuf_ptr(state->incoming_packet)[4];
1609 DBG(debug("input: padlen %d", padlen));
1611 if ((r = sshpkt_disconnect(ssh,
1612 "Corrupted padlen %d on input.", padlen)) != 0 ||
1613 (r = ssh_packet_write_wait(ssh)) != 0)
1615 return SSH_ERR_CONN_CORRUPT;
1618 /* skip packet size + padlen, discard padding */
1619 if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1620 ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1623 DBG(debug("input: len before de-compress %zd",
1624 sshbuf_len(state->incoming_packet)));
1625 if (comp && comp->enabled) {
1626 sshbuf_reset(state->compression_buffer);
1627 if ((r = uncompress_buffer(ssh, state->incoming_packet,
1628 state->compression_buffer)) != 0)
1630 sshbuf_reset(state->incoming_packet);
1631 if ((r = sshbuf_putb(state->incoming_packet,
1632 state->compression_buffer)) != 0)
1634 DBG(debug("input: len after de-compress %zd",
1635 sshbuf_len(state->incoming_packet)));
1638 * get packet type, implies consume.
1639 * return length of payload (without type field)
1641 if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1643 if (ssh_packet_log_type(*typep))
1644 debug3("receive packet: type %u", *typep);
1645 if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1646 if ((r = sshpkt_disconnect(ssh,
1647 "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1648 (r = ssh_packet_write_wait(ssh)) != 0)
1650 return SSH_ERR_PROTOCOL_ERROR;
1652 if (state->hook_in != NULL &&
1653 (r = state->hook_in(ssh, state->incoming_packet, typep,
1654 state->hook_in_ctx)) != 0)
1656 if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1657 r = ssh_packet_enable_delayed_compress(ssh);
1661 fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1662 sshbuf_dump(state->incoming_packet, stderr);
1664 /* reset for next packet */
1667 /* do we need to rekey? */
1668 if (ssh_packet_need_rekeying(ssh, 0)) {
1669 debug3("%s: rekex triggered", __func__);
1670 if ((r = kex_start_rekex(ssh)) != 0)
1678 ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1680 struct session_state *state = ssh->state;
1681 u_int reason, seqnr;
1687 r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1691 state->keep_alive_timeouts = 0;
1692 DBG(debug("received packet type %d", *typep));
1695 case SSH2_MSG_IGNORE:
1696 debug3("Received SSH2_MSG_IGNORE");
1698 case SSH2_MSG_DEBUG:
1699 if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1700 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1701 (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1705 debug("Remote: %.900s", msg);
1708 case SSH2_MSG_DISCONNECT:
1709 if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1710 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1712 /* Ignore normal client exit notifications */
1713 do_log2(ssh->state->server_side &&
1714 reason == SSH2_DISCONNECT_BY_APPLICATION ?
1715 SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1716 "Received disconnect from %s port %d:"
1717 "%u: %.400s", ssh_remote_ipaddr(ssh),
1718 ssh_remote_port(ssh), reason, msg);
1720 return SSH_ERR_DISCONNECTED;
1721 case SSH2_MSG_UNIMPLEMENTED:
1722 if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1724 debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1734 * Buffers the given amount of input characters. This is intended to be used
1735 * together with packet_read_poll.
1739 ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1741 struct session_state *state = ssh->state;
1744 if (state->packet_discard) {
1745 state->keep_alive_timeouts = 0; /* ?? */
1746 if (len >= state->packet_discard) {
1747 if ((r = ssh_packet_stop_discard(ssh)) != 0)
1750 state->packet_discard -= len;
1753 if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1760 ssh_packet_remaining(struct ssh *ssh)
1762 return sshbuf_len(ssh->state->incoming_packet);
1766 * Sends a diagnostic message from the server to the client. This message
1767 * can be sent at any time (but not while constructing another message). The
1768 * message is printed immediately, but only if the client is being executed
1769 * in verbose mode. These messages are primarily intended to ease debugging
1770 * authentication problems. The length of the formatted message must not
1771 * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1774 ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1780 if ((ssh->compat & SSH_BUG_DEBUG))
1783 va_start(args, fmt);
1784 vsnprintf(buf, sizeof(buf), fmt, args);
1787 debug3("sending debug message: %s", buf);
1789 if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1790 (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1791 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1792 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1793 (r = sshpkt_send(ssh)) != 0 ||
1794 (r = ssh_packet_write_wait(ssh)) != 0)
1795 fatal("%s: %s", __func__, ssh_err(r));
1799 sshpkt_fmt_connection_id(struct ssh *ssh, char *s, size_t l)
1801 snprintf(s, l, "%.200s%s%s port %d",
1802 ssh->log_preamble ? ssh->log_preamble : "",
1803 ssh->log_preamble ? " " : "",
1804 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1808 * Pretty-print connection-terminating errors and exit.
1811 sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1813 char remote_id[512];
1815 sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1818 case SSH_ERR_CONN_CLOSED:
1819 ssh_packet_clear_keys(ssh);
1820 logdie("Connection closed by %s", remote_id);
1821 case SSH_ERR_CONN_TIMEOUT:
1822 ssh_packet_clear_keys(ssh);
1823 logdie("Connection %s %s timed out",
1824 ssh->state->server_side ? "from" : "to", remote_id);
1825 case SSH_ERR_DISCONNECTED:
1826 ssh_packet_clear_keys(ssh);
1827 logdie("Disconnected from %s", remote_id);
1828 case SSH_ERR_SYSTEM_ERROR:
1829 if (errno == ECONNRESET) {
1830 ssh_packet_clear_keys(ssh);
1831 logdie("Connection reset by %s", remote_id);
1834 case SSH_ERR_NO_CIPHER_ALG_MATCH:
1835 case SSH_ERR_NO_MAC_ALG_MATCH:
1836 case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1837 case SSH_ERR_NO_KEX_ALG_MATCH:
1838 case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1839 if (ssh && ssh->kex && ssh->kex->failed_choice) {
1840 BLACKLIST_NOTIFY(BLACKLIST_AUTH_FAIL, "ssh");
1841 ssh_packet_clear_keys(ssh);
1842 logdie("Unable to negotiate with %s: %s. "
1843 "Their offer: %s", remote_id, ssh_err(r),
1844 ssh->kex->failed_choice);
1848 ssh_packet_clear_keys(ssh);
1849 logdie("%s%sConnection %s %s: %s",
1850 tag != NULL ? tag : "", tag != NULL ? ": " : "",
1851 ssh->state->server_side ? "from" : "to",
1852 remote_id, ssh_err(r));
1857 * Logs the error plus constructs and sends a disconnect packet, closes the
1858 * connection, and exits. This function never returns. The error message
1859 * should not contain a newline. The length of the formatted message must
1860 * not exceed 1024 bytes.
1863 ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1865 char buf[1024], remote_id[512];
1867 static int disconnecting = 0;
1870 if (disconnecting) /* Guard against recursive invocations. */
1871 fatal("packet_disconnect called recursively.");
1875 * Format the message. Note that the caller must make sure the
1876 * message is of limited size.
1878 sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1879 va_start(args, fmt);
1880 vsnprintf(buf, sizeof(buf), fmt, args);
1883 /* Display the error locally */
1884 logit("Disconnecting %s: %.100s", remote_id, buf);
1887 * Send the disconnect message to the other side, and wait
1888 * for it to get sent.
1890 if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1891 sshpkt_fatal(ssh, __func__, r);
1893 if ((r = ssh_packet_write_wait(ssh)) != 0)
1894 sshpkt_fatal(ssh, __func__, r);
1896 /* Close the connection. */
1897 ssh_packet_close(ssh);
1902 * Checks if there is any buffered output, and tries to write some of
1906 ssh_packet_write_poll(struct ssh *ssh)
1908 struct session_state *state = ssh->state;
1909 int len = sshbuf_len(state->output);
1913 len = write(state->connection_out,
1914 sshbuf_ptr(state->output), len);
1916 if (errno == EINTR || errno == EAGAIN ||
1917 errno == EWOULDBLOCK)
1919 return SSH_ERR_SYSTEM_ERROR;
1922 return SSH_ERR_CONN_CLOSED;
1923 if ((r = sshbuf_consume(state->output, len)) != 0)
1930 * Calls packet_write_poll repeatedly until all pending output data has been
1934 ssh_packet_write_wait(struct ssh *ssh)
1937 int ret, r, ms_remain = 0;
1938 struct timeval start, timeout, *timeoutp = NULL;
1939 struct session_state *state = ssh->state;
1941 setp = calloc(howmany(state->connection_out + 1,
1942 NFDBITS), sizeof(fd_mask));
1944 return SSH_ERR_ALLOC_FAIL;
1945 if ((r = ssh_packet_write_poll(ssh)) != 0) {
1949 while (ssh_packet_have_data_to_write(ssh)) {
1950 memset(setp, 0, howmany(state->connection_out + 1,
1951 NFDBITS) * sizeof(fd_mask));
1952 FD_SET(state->connection_out, setp);
1954 if (state->packet_timeout_ms > 0) {
1955 ms_remain = state->packet_timeout_ms;
1956 timeoutp = &timeout;
1959 if (state->packet_timeout_ms != -1) {
1960 ms_to_timeval(&timeout, ms_remain);
1961 monotime_tv(&start);
1963 if ((ret = select(state->connection_out + 1,
1964 NULL, setp, NULL, timeoutp)) >= 0)
1966 if (errno != EAGAIN && errno != EINTR &&
1967 errno != EWOULDBLOCK)
1969 if (state->packet_timeout_ms == -1)
1971 ms_subtract_diff(&start, &ms_remain);
1972 if (ms_remain <= 0) {
1979 return SSH_ERR_CONN_TIMEOUT;
1981 if ((r = ssh_packet_write_poll(ssh)) != 0) {
1990 /* Returns true if there is buffered data to write to the connection. */
1993 ssh_packet_have_data_to_write(struct ssh *ssh)
1995 return sshbuf_len(ssh->state->output) != 0;
1998 /* Returns true if there is not too much data to write to the connection. */
2001 ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
2003 if (ssh->state->interactive_mode)
2004 return sshbuf_len(ssh->state->output) < 16384;
2006 return sshbuf_len(ssh->state->output) < 128 * 1024;
2010 ssh_packet_set_tos(struct ssh *ssh, int tos)
2012 #ifndef IP_TOS_IS_BROKEN
2013 if (!ssh_packet_connection_is_on_socket(ssh) || tos == INT_MAX)
2015 switch (ssh_packet_connection_af(ssh)) {
2018 debug3("%s: set IP_TOS 0x%02x", __func__, tos);
2019 if (setsockopt(ssh->state->connection_in,
2020 IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2021 error("setsockopt IP_TOS %d: %.100s:",
2022 tos, strerror(errno));
2024 # endif /* IP_TOS */
2027 debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
2028 if (setsockopt(ssh->state->connection_in,
2029 IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2030 error("setsockopt IPV6_TCLASS %d: %.100s:",
2031 tos, strerror(errno));
2033 # endif /* IPV6_TCLASS */
2035 #endif /* IP_TOS_IS_BROKEN */
2038 /* Informs that the current session is interactive. Sets IP flags for that. */
2041 ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
2043 struct session_state *state = ssh->state;
2045 if (state->set_interactive_called)
2047 state->set_interactive_called = 1;
2049 /* Record that we are in interactive mode. */
2050 state->interactive_mode = interactive;
2052 /* Only set socket options if using a socket. */
2053 if (!ssh_packet_connection_is_on_socket(ssh))
2055 set_nodelay(state->connection_in);
2056 ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2060 /* Returns true if the current connection is interactive. */
2063 ssh_packet_is_interactive(struct ssh *ssh)
2065 return ssh->state->interactive_mode;
2069 ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
2071 struct session_state *state = ssh->state;
2073 if (state->set_maxsize_called) {
2074 logit("packet_set_maxsize: called twice: old %d new %d",
2075 state->max_packet_size, s);
2078 if (s < 4 * 1024 || s > 1024 * 1024) {
2079 logit("packet_set_maxsize: bad size %d", s);
2082 state->set_maxsize_called = 1;
2083 debug("packet_set_maxsize: setting to %d", s);
2084 state->max_packet_size = s;
2089 ssh_packet_inc_alive_timeouts(struct ssh *ssh)
2091 return ++ssh->state->keep_alive_timeouts;
2095 ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
2097 ssh->state->keep_alive_timeouts = ka;
2101 ssh_packet_get_maxsize(struct ssh *ssh)
2103 return ssh->state->max_packet_size;
2107 ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, u_int32_t seconds)
2109 debug3("rekey after %llu bytes, %u seconds", (unsigned long long)bytes,
2110 (unsigned int)seconds);
2111 ssh->state->rekey_limit = bytes;
2112 ssh->state->rekey_interval = seconds;
2116 ssh_packet_get_rekey_timeout(struct ssh *ssh)
2120 seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
2122 return (seconds <= 0 ? 1 : seconds);
2126 ssh_packet_set_server(struct ssh *ssh)
2128 ssh->state->server_side = 1;
2132 ssh_packet_set_authenticated(struct ssh *ssh)
2134 ssh->state->after_authentication = 1;
2138 ssh_packet_get_input(struct ssh *ssh)
2140 return (void *)ssh->state->input;
2144 ssh_packet_get_output(struct ssh *ssh)
2146 return (void *)ssh->state->output;
2149 /* Reset after_authentication and reset compression in post-auth privsep */
2151 ssh_packet_set_postauth(struct ssh *ssh)
2155 debug("%s: called", __func__);
2156 /* This was set in net child, but is not visible in user child */
2157 ssh->state->after_authentication = 1;
2158 ssh->state->rekeying = 0;
2159 if ((r = ssh_packet_enable_delayed_compress(ssh)) != 0)
2164 /* Packet state (de-)serialization for privsep */
2166 /* turn kex into a blob for packet state serialization */
2168 kex_to_blob(struct sshbuf *m, struct kex *kex)
2172 if ((r = sshbuf_put_string(m, kex->session_id,
2173 kex->session_id_len)) != 0 ||
2174 (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2175 (r = sshbuf_put_cstring(m, kex->hostkey_alg)) != 0 ||
2176 (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2177 (r = sshbuf_put_u32(m, kex->hostkey_nid)) != 0 ||
2178 (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2179 (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2180 (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2181 (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2182 (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2183 (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2188 /* turn key exchange results into a blob for packet state serialization */
2190 newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2193 struct sshcipher_ctx *cc;
2194 struct sshcomp *comp;
2197 struct newkeys *newkey;
2200 if ((newkey = ssh->state->newkeys[mode]) == NULL)
2201 return SSH_ERR_INTERNAL_ERROR;
2204 comp = &newkey->comp;
2205 cc = (mode == MODE_OUT) ? ssh->state->send_context :
2206 ssh->state->receive_context;
2207 if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2209 if ((b = sshbuf_new()) == NULL)
2210 return SSH_ERR_ALLOC_FAIL;
2211 if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2212 (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2213 (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2214 (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2215 (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2217 if (cipher_authlen(enc->cipher) == 0) {
2218 if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2219 (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2220 (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2223 if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2224 (r = sshbuf_put_cstring(b, comp->name)) != 0)
2226 r = sshbuf_put_stringb(m, b);
2232 /* serialize packet state into a blob */
2234 ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2236 struct session_state *state = ssh->state;
2239 if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2240 (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2241 (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
2242 (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
2243 (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
2244 (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2245 (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2246 (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2247 (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2248 (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2249 (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2250 (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2251 (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0 ||
2252 (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2253 (r = sshbuf_put_stringb(m, state->output)) != 0)
2259 /* restore key exchange results from blob for packet state de-serialization */
2261 newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2263 struct sshbuf *b = NULL;
2264 struct sshcomp *comp;
2267 struct newkeys *newkey = NULL;
2268 size_t keylen, ivlen, maclen;
2271 if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2272 r = SSH_ERR_ALLOC_FAIL;
2275 if ((r = sshbuf_froms(m, &b)) != 0)
2278 sshbuf_dump(b, stderr);
2282 comp = &newkey->comp;
2284 if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2285 (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2286 (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2287 (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2288 (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2290 if ((enc->cipher = cipher_by_name(enc->name)) == NULL) {
2291 r = SSH_ERR_INVALID_FORMAT;
2294 if (cipher_authlen(enc->cipher) == 0) {
2295 if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2297 if ((r = mac_setup(mac, mac->name)) != 0)
2299 if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2300 (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2302 if (maclen > mac->key_len) {
2303 r = SSH_ERR_INVALID_FORMAT;
2306 mac->key_len = maclen;
2308 if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2309 (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2311 if (sshbuf_len(b) != 0) {
2312 r = SSH_ERR_INVALID_FORMAT;
2315 enc->key_len = keylen;
2316 enc->iv_len = ivlen;
2317 ssh->kex->newkeys[mode] = newkey;
2326 /* restore kex from blob for packet state de-serialization */
2328 kex_from_blob(struct sshbuf *m, struct kex **kexp)
2333 if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2334 (kex->my = sshbuf_new()) == NULL ||
2335 (kex->peer = sshbuf_new()) == NULL) {
2336 r = SSH_ERR_ALLOC_FAIL;
2339 if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2340 (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2341 (r = sshbuf_get_cstring(m, &kex->hostkey_alg, NULL)) != 0 ||
2342 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2343 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_nid)) != 0 ||
2344 (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2345 (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2346 (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2347 (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2348 (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2349 (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2355 if (r != 0 || kexp == NULL) {
2357 sshbuf_free(kex->my);
2358 sshbuf_free(kex->peer);
2370 * Restore packet state from content of blob 'm' (de-serialization).
2371 * Note that 'm' will be partially consumed on parsing or any other errors.
2374 ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2376 struct session_state *state = ssh->state;
2377 const u_char *input, *output;
2381 if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2382 (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2383 (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
2384 (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
2385 (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
2386 (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2387 (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2388 (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2389 (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2390 (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2391 (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2392 (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2393 (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2396 * We set the time here so that in post-auth privsep slave we
2397 * count from the completion of the authentication.
2399 state->rekey_time = monotime();
2400 /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2401 if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2402 (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2405 if ((r = ssh_packet_set_postauth(ssh)) != 0)
2408 sshbuf_reset(state->input);
2409 sshbuf_reset(state->output);
2410 if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2411 (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2412 (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2413 (r = sshbuf_put(state->output, output, olen)) != 0)
2417 return SSH_ERR_INVALID_FORMAT;
2418 debug3("%s: done", __func__);
2424 /* put data to the outgoing packet */
2427 sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2429 return sshbuf_put(ssh->state->outgoing_packet, v, len);
2433 sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2435 return sshbuf_putb(ssh->state->outgoing_packet, b);
2439 sshpkt_put_u8(struct ssh *ssh, u_char val)
2441 return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2445 sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2447 return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2451 sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2453 return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2457 sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2459 return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2463 sshpkt_put_cstring(struct ssh *ssh, const void *v)
2465 return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2469 sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2471 return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2475 #ifdef OPENSSL_HAS_ECC
2477 sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2479 return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2481 #endif /* OPENSSL_HAS_ECC */
2485 sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2487 return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2489 #endif /* WITH_OPENSSL */
2491 /* fetch data from the incoming packet */
2494 sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2496 return sshbuf_get(ssh->state->incoming_packet, valp, len);
2500 sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2502 return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2506 sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2508 return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2512 sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2514 return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2518 sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2520 return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2524 sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2526 return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2530 sshpkt_peek_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2532 return sshbuf_peek_string_direct(ssh->state->incoming_packet, valp, lenp);
2536 sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2538 return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2542 #ifdef OPENSSL_HAS_ECC
2544 sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2546 return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2548 #endif /* OPENSSL_HAS_ECC */
2552 sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2554 return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2556 #endif /* WITH_OPENSSL */
2559 sshpkt_get_end(struct ssh *ssh)
2561 if (sshbuf_len(ssh->state->incoming_packet) > 0)
2562 return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2567 sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2570 *lenp = sshbuf_len(ssh->state->incoming_packet);
2571 return sshbuf_ptr(ssh->state->incoming_packet);
2574 /* start a new packet */
2577 sshpkt_start(struct ssh *ssh, u_char type)
2579 u_char buf[6]; /* u32 packet length, u8 pad len, u8 type */
2581 DBG(debug("packet_start[%d]", type));
2582 memset(buf, 0, sizeof(buf));
2583 buf[sizeof(buf) - 1] = type;
2584 sshbuf_reset(ssh->state->outgoing_packet);
2585 return sshbuf_put(ssh->state->outgoing_packet, buf, sizeof(buf));
2589 ssh_packet_send_mux(struct ssh *ssh)
2591 struct session_state *state = ssh->state;
2597 return SSH_ERR_INTERNAL_ERROR;
2598 len = sshbuf_len(state->outgoing_packet);
2600 return SSH_ERR_INTERNAL_ERROR;
2601 cp = sshbuf_mutable_ptr(state->outgoing_packet);
2603 if (ssh_packet_log_type(type))
2604 debug3("%s: type %u", __func__, type);
2605 /* drop everything, but the connection protocol */
2606 if (type >= SSH2_MSG_CONNECTION_MIN &&
2607 type <= SSH2_MSG_CONNECTION_MAX) {
2608 POKE_U32(cp, len - 4);
2609 if ((r = sshbuf_putb(state->output,
2610 state->outgoing_packet)) != 0)
2612 /* sshbuf_dump(state->output, stderr); */
2614 sshbuf_reset(state->outgoing_packet);
2619 * 9.2. Ignored Data Message
2621 * byte SSH_MSG_IGNORE
2624 * All implementations MUST understand (and ignore) this message at any
2625 * time (after receiving the protocol version). No implementation is
2626 * required to send them. This message can be used as an additional
2627 * protection measure against advanced traffic analysis techniques.
2630 sshpkt_msg_ignore(struct ssh *ssh, u_int nbytes)
2636 if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
2637 (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2639 for (i = 0; i < nbytes; i++) {
2642 if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2652 sshpkt_send(struct ssh *ssh)
2654 if (ssh->state && ssh->state->mux)
2655 return ssh_packet_send_mux(ssh);
2656 return ssh_packet_send2(ssh);
2660 sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2666 va_start(args, fmt);
2667 vsnprintf(buf, sizeof(buf), fmt, args);
2670 if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2671 (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2672 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2673 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2674 (r = sshpkt_send(ssh)) != 0)
2679 /* roundup current message to pad bytes */
2681 sshpkt_add_padding(struct ssh *ssh, u_char pad)
2683 ssh->state->extra_pad = pad;