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.
42 #include <sys/types.h>
43 #include "openbsd-compat/sys-queue.h"
44 #include <sys/socket.h>
45 #ifdef HAVE_SYS_TIME_H
46 # include <sys/time.h>
49 #include <netinet/in.h>
50 #include <netinet/ip.h>
51 #include <arpa/inet.h>
66 #include "buffer.h" /* typedefs XXX */
67 #include "key.h" /* typedefs XXX */
93 #define PACKET_MAX_SIZE (256 * 1024)
103 TAILQ_ENTRY(packet) next;
105 struct sshbuf *payload;
108 struct session_state {
110 * This variable contains the file descriptors used for
111 * communicating with the other side. connection_in is used for
112 * reading; connection_out for writing. These can be the same
113 * descriptor, in which case it is assumed to be a socket.
118 /* Protocol flags for the remote side. */
119 u_int remote_protocol_flags;
121 /* Encryption context for receiving data. Only used for decryption. */
122 struct sshcipher_ctx *receive_context;
124 /* Encryption context for sending data. Only used for encryption. */
125 struct sshcipher_ctx *send_context;
127 /* Buffer for raw input data from the socket. */
128 struct sshbuf *input;
130 /* Buffer for raw output data going to the socket. */
131 struct sshbuf *output;
133 /* Buffer for the partial outgoing packet being constructed. */
134 struct sshbuf *outgoing_packet;
136 /* Buffer for the incoming packet currently being processed. */
137 struct sshbuf *incoming_packet;
139 /* Scratch buffer for packet compression/decompression. */
140 struct sshbuf *compression_buffer;
142 /* Incoming/outgoing compression dictionaries */
143 z_stream compression_in_stream;
144 z_stream compression_out_stream;
145 int compression_in_started;
146 int compression_out_started;
147 int compression_in_failures;
148 int compression_out_failures;
151 * Flag indicating whether packet compression/decompression is
154 int packet_compression;
156 /* default maximum packet size */
157 u_int max_packet_size;
159 /* Flag indicating whether this module has been initialized. */
162 /* Set to true if the connection is interactive. */
163 int interactive_mode;
165 /* Set to true if we are the server side. */
168 /* Set to true if we are authenticated. */
169 int after_authentication;
171 int keep_alive_timeouts;
173 /* The maximum time that we will wait to send or receive a packet */
174 int packet_timeout_ms;
176 /* Session key information for Encryption and MAC */
177 struct newkeys *newkeys[MODE_MAX];
178 struct packet_state p_read, p_send;
180 /* Volume-based rekeying */
181 u_int64_t max_blocks_in, max_blocks_out, rekey_limit;
183 /* Time-based rekeying */
184 u_int32_t rekey_interval; /* how often in seconds */
185 time_t rekey_time; /* time of last rekeying */
187 /* roundup current message to extra_pad bytes */
190 /* XXX discard incoming data after MAC error */
191 u_int packet_discard;
192 size_t packet_discard_mac_already;
193 struct sshmac *packet_discard_mac;
195 /* Used in packet_read_poll2() */
198 /* Used in packet_send2 */
201 /* Used in ssh_packet_send_mux() */
204 /* Used in packet_set_interactive */
205 int set_interactive_called;
207 /* Used in packet_set_maxsize */
208 int set_maxsize_called;
210 /* One-off warning about weak ciphers */
211 int cipher_warning_done;
213 /* Hook for fuzzing inbound packets */
214 ssh_packet_hook_fn *hook_in;
217 TAILQ_HEAD(, packet) outgoing;
221 ssh_alloc_session_state(void)
223 struct ssh *ssh = NULL;
224 struct session_state *state = NULL;
226 if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
227 (state = calloc(1, sizeof(*state))) == NULL ||
228 (state->input = sshbuf_new()) == NULL ||
229 (state->output = sshbuf_new()) == NULL ||
230 (state->outgoing_packet = sshbuf_new()) == NULL ||
231 (state->incoming_packet = sshbuf_new()) == NULL)
233 TAILQ_INIT(&state->outgoing);
234 TAILQ_INIT(&ssh->private_keys);
235 TAILQ_INIT(&ssh->public_keys);
236 state->connection_in = -1;
237 state->connection_out = -1;
238 state->max_packet_size = 32768;
239 state->packet_timeout_ms = -1;
240 state->p_send.packets = state->p_read.packets = 0;
241 state->initialized = 1;
243 * ssh_packet_send2() needs to queue packets until
244 * we've done the initial key exchange.
251 sshbuf_free(state->input);
252 sshbuf_free(state->output);
253 sshbuf_free(state->incoming_packet);
254 sshbuf_free(state->outgoing_packet);
262 ssh_packet_set_input_hook(struct ssh *ssh, ssh_packet_hook_fn *hook, void *ctx)
264 ssh->state->hook_in = hook;
265 ssh->state->hook_in_ctx = ctx;
268 /* Returns nonzero if rekeying is in progress */
270 ssh_packet_is_rekeying(struct ssh *ssh)
272 return ssh->state->rekeying ||
273 (ssh->kex != NULL && ssh->kex->done == 0);
277 * Sets the descriptors used for communication.
280 ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
282 struct session_state *state;
283 const struct sshcipher *none = cipher_by_name("none");
287 error("%s: cannot load cipher 'none'", __func__);
291 ssh = ssh_alloc_session_state();
293 error("%s: cound not allocate state", __func__);
297 state->connection_in = fd_in;
298 state->connection_out = fd_out;
299 if ((r = cipher_init(&state->send_context, none,
300 (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
301 (r = cipher_init(&state->receive_context, none,
302 (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
303 error("%s: cipher_init failed: %s", __func__, ssh_err(r));
304 free(ssh); /* XXX need ssh_free_session_state? */
307 state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
309 * Cache the IP address of the remote connection for use in error
310 * messages that might be generated after the connection has closed.
312 (void)ssh_remote_ipaddr(ssh);
317 ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
319 struct session_state *state = ssh->state;
321 if (timeout <= 0 || count <= 0) {
322 state->packet_timeout_ms = -1;
325 if ((INT_MAX / 1000) / count < timeout)
326 state->packet_timeout_ms = INT_MAX;
328 state->packet_timeout_ms = timeout * count * 1000;
332 ssh_packet_set_mux(struct ssh *ssh)
335 ssh->state->rekeying = 0;
339 ssh_packet_get_mux(struct ssh *ssh)
341 return ssh->state->mux;
345 ssh_packet_set_log_preamble(struct ssh *ssh, const char *fmt, ...)
350 free(ssh->log_preamble);
352 ssh->log_preamble = NULL;
355 r = vasprintf(&ssh->log_preamble, fmt, args);
357 if (r < 0 || ssh->log_preamble == NULL)
358 return SSH_ERR_ALLOC_FAIL;
364 ssh_packet_stop_discard(struct ssh *ssh)
366 struct session_state *state = ssh->state;
369 if (state->packet_discard_mac) {
371 size_t dlen = PACKET_MAX_SIZE;
373 if (dlen > state->packet_discard_mac_already)
374 dlen -= state->packet_discard_mac_already;
375 memset(buf, 'a', sizeof(buf));
376 while (sshbuf_len(state->incoming_packet) < dlen)
377 if ((r = sshbuf_put(state->incoming_packet, buf,
380 (void) mac_compute(state->packet_discard_mac,
382 sshbuf_ptr(state->incoming_packet), dlen,
385 logit("Finished discarding for %.200s port %d",
386 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
387 return SSH_ERR_MAC_INVALID;
391 ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
392 struct sshmac *mac, size_t mac_already, u_int discard)
394 struct session_state *state = ssh->state;
397 if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
398 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
400 return SSH_ERR_MAC_INVALID;
403 * Record number of bytes over which the mac has already
404 * been computed in order to minimize timing attacks.
406 if (mac && mac->enabled) {
407 state->packet_discard_mac = mac;
408 state->packet_discard_mac_already = mac_already;
410 if (sshbuf_len(state->input) >= discard)
411 return ssh_packet_stop_discard(ssh);
412 state->packet_discard = discard - sshbuf_len(state->input);
416 /* Returns 1 if remote host is connected via socket, 0 if not. */
419 ssh_packet_connection_is_on_socket(struct ssh *ssh)
421 struct session_state *state = ssh->state;
422 struct sockaddr_storage from, to;
423 socklen_t fromlen, tolen;
425 if (state->connection_in == -1 || state->connection_out == -1)
428 /* filedescriptors in and out are the same, so it's a socket */
429 if (state->connection_in == state->connection_out)
431 fromlen = sizeof(from);
432 memset(&from, 0, sizeof(from));
433 if (getpeername(state->connection_in, (struct sockaddr *)&from,
437 memset(&to, 0, sizeof(to));
438 if (getpeername(state->connection_out, (struct sockaddr *)&to,
441 if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
443 if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
449 ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
452 *ibytes = ssh->state->p_read.bytes;
454 *obytes = ssh->state->p_send.bytes;
458 ssh_packet_connection_af(struct ssh *ssh)
460 struct sockaddr_storage to;
461 socklen_t tolen = sizeof(to);
463 memset(&to, 0, sizeof(to));
464 if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
468 if (to.ss_family == AF_INET6 &&
469 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr))
475 /* Sets the connection into non-blocking mode. */
478 ssh_packet_set_nonblocking(struct ssh *ssh)
480 /* Set the socket into non-blocking mode. */
481 set_nonblock(ssh->state->connection_in);
483 if (ssh->state->connection_out != ssh->state->connection_in)
484 set_nonblock(ssh->state->connection_out);
487 /* Returns the socket used for reading. */
490 ssh_packet_get_connection_in(struct ssh *ssh)
492 return ssh->state->connection_in;
495 /* Returns the descriptor used for writing. */
498 ssh_packet_get_connection_out(struct ssh *ssh)
500 return ssh->state->connection_out;
504 * Returns the IP-address of the remote host as a string. The returned
505 * string must not be freed.
509 ssh_remote_ipaddr(struct ssh *ssh)
511 const int sock = ssh->state->connection_in;
513 /* Check whether we have cached the ipaddr. */
514 if (ssh->remote_ipaddr == NULL) {
515 if (ssh_packet_connection_is_on_socket(ssh)) {
516 ssh->remote_ipaddr = get_peer_ipaddr(sock);
517 ssh->remote_port = get_peer_port(sock);
518 ssh->local_ipaddr = get_local_ipaddr(sock);
519 ssh->local_port = get_local_port(sock);
521 ssh->remote_ipaddr = strdup("UNKNOWN");
522 ssh->remote_port = 65535;
523 ssh->local_ipaddr = strdup("UNKNOWN");
524 ssh->local_port = 65535;
527 return ssh->remote_ipaddr;
530 /* Returns the port number of the remote host. */
533 ssh_remote_port(struct ssh *ssh)
535 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
536 return ssh->remote_port;
540 * Returns the IP-address of the local host as a string. The returned
541 * string must not be freed.
545 ssh_local_ipaddr(struct ssh *ssh)
547 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
548 return ssh->local_ipaddr;
551 /* Returns the port number of the local host. */
554 ssh_local_port(struct ssh *ssh)
556 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
557 return ssh->local_port;
560 /* Returns the routing domain of the input socket, or NULL if unavailable */
562 ssh_packet_rdomain_in(struct ssh *ssh)
564 if (ssh->rdomain_in != NULL)
565 return ssh->rdomain_in;
566 if (!ssh_packet_connection_is_on_socket(ssh))
568 ssh->rdomain_in = get_rdomain(ssh->state->connection_in);
569 return ssh->rdomain_in;
572 /* Closes the connection and clears and frees internal data structures. */
575 ssh_packet_close_internal(struct ssh *ssh, int do_close)
577 struct session_state *state = ssh->state;
580 if (!state->initialized)
582 state->initialized = 0;
584 if (state->connection_in == state->connection_out) {
585 close(state->connection_out);
587 close(state->connection_in);
588 close(state->connection_out);
591 sshbuf_free(state->input);
592 sshbuf_free(state->output);
593 sshbuf_free(state->outgoing_packet);
594 sshbuf_free(state->incoming_packet);
595 for (mode = 0; mode < MODE_MAX; mode++) {
596 kex_free_newkeys(state->newkeys[mode]); /* current keys */
597 state->newkeys[mode] = NULL;
598 ssh_clear_newkeys(ssh, mode); /* next keys */
600 /* comression state is in shared mem, so we can only release it once */
601 if (do_close && state->compression_buffer) {
602 sshbuf_free(state->compression_buffer);
603 if (state->compression_out_started) {
604 z_streamp stream = &state->compression_out_stream;
605 debug("compress outgoing: "
606 "raw data %llu, compressed %llu, factor %.2f",
607 (unsigned long long)stream->total_in,
608 (unsigned long long)stream->total_out,
609 stream->total_in == 0 ? 0.0 :
610 (double) stream->total_out / stream->total_in);
611 if (state->compression_out_failures == 0)
614 if (state->compression_in_started) {
615 z_streamp stream = &state->compression_in_stream;
616 debug("compress incoming: "
617 "raw data %llu, compressed %llu, factor %.2f",
618 (unsigned long long)stream->total_out,
619 (unsigned long long)stream->total_in,
620 stream->total_out == 0 ? 0.0 :
621 (double) stream->total_in / stream->total_out);
622 if (state->compression_in_failures == 0)
626 cipher_free(state->send_context);
627 cipher_free(state->receive_context);
628 state->send_context = state->receive_context = NULL;
630 free(ssh->remote_ipaddr);
631 ssh->remote_ipaddr = NULL;
638 ssh_packet_close(struct ssh *ssh)
640 ssh_packet_close_internal(ssh, 1);
644 ssh_packet_clear_keys(struct ssh *ssh)
646 ssh_packet_close_internal(ssh, 0);
649 /* Sets remote side protocol flags. */
652 ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
654 ssh->state->remote_protocol_flags = protocol_flags;
657 /* Returns the remote protocol flags set earlier by the above function. */
660 ssh_packet_get_protocol_flags(struct ssh *ssh)
662 return ssh->state->remote_protocol_flags;
666 * Starts packet compression from the next packet on in both directions.
667 * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
671 ssh_packet_init_compression(struct ssh *ssh)
673 if (!ssh->state->compression_buffer &&
674 ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
675 return SSH_ERR_ALLOC_FAIL;
680 start_compression_out(struct ssh *ssh, int level)
682 if (level < 1 || level > 9)
683 return SSH_ERR_INVALID_ARGUMENT;
684 debug("Enabling compression at level %d.", level);
685 if (ssh->state->compression_out_started == 1)
686 deflateEnd(&ssh->state->compression_out_stream);
687 switch (deflateInit(&ssh->state->compression_out_stream, level)) {
689 ssh->state->compression_out_started = 1;
692 return SSH_ERR_ALLOC_FAIL;
694 return SSH_ERR_INTERNAL_ERROR;
700 start_compression_in(struct ssh *ssh)
702 if (ssh->state->compression_in_started == 1)
703 inflateEnd(&ssh->state->compression_in_stream);
704 switch (inflateInit(&ssh->state->compression_in_stream)) {
706 ssh->state->compression_in_started = 1;
709 return SSH_ERR_ALLOC_FAIL;
711 return SSH_ERR_INTERNAL_ERROR;
717 ssh_packet_start_compression(struct ssh *ssh, int level)
721 if (ssh->state->packet_compression)
722 return SSH_ERR_INTERNAL_ERROR;
723 ssh->state->packet_compression = 1;
724 if ((r = ssh_packet_init_compression(ssh)) != 0 ||
725 (r = start_compression_in(ssh)) != 0 ||
726 (r = start_compression_out(ssh, level)) != 0)
731 /* XXX remove need for separate compression buffer */
733 compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
738 if (ssh->state->compression_out_started != 1)
739 return SSH_ERR_INTERNAL_ERROR;
741 /* This case is not handled below. */
742 if (sshbuf_len(in) == 0)
745 /* Input is the contents of the input buffer. */
746 if ((ssh->state->compression_out_stream.next_in =
747 sshbuf_mutable_ptr(in)) == NULL)
748 return SSH_ERR_INTERNAL_ERROR;
749 ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
751 /* Loop compressing until deflate() returns with avail_out != 0. */
753 /* Set up fixed-size output buffer. */
754 ssh->state->compression_out_stream.next_out = buf;
755 ssh->state->compression_out_stream.avail_out = sizeof(buf);
757 /* Compress as much data into the buffer as possible. */
758 status = deflate(&ssh->state->compression_out_stream,
762 return SSH_ERR_ALLOC_FAIL;
764 /* Append compressed data to output_buffer. */
765 if ((r = sshbuf_put(out, buf, sizeof(buf) -
766 ssh->state->compression_out_stream.avail_out)) != 0)
771 ssh->state->compression_out_failures++;
772 return SSH_ERR_INVALID_FORMAT;
774 } while (ssh->state->compression_out_stream.avail_out == 0);
779 uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
784 if (ssh->state->compression_in_started != 1)
785 return SSH_ERR_INTERNAL_ERROR;
787 if ((ssh->state->compression_in_stream.next_in =
788 sshbuf_mutable_ptr(in)) == NULL)
789 return SSH_ERR_INTERNAL_ERROR;
790 ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
793 /* Set up fixed-size output buffer. */
794 ssh->state->compression_in_stream.next_out = buf;
795 ssh->state->compression_in_stream.avail_out = sizeof(buf);
797 status = inflate(&ssh->state->compression_in_stream,
801 if ((r = sshbuf_put(out, buf, sizeof(buf) -
802 ssh->state->compression_in_stream.avail_out)) != 0)
807 * Comments in zlib.h say that we should keep calling
808 * inflate() until we get an error. This appears to
809 * be the error that we get.
813 return SSH_ERR_INVALID_FORMAT;
815 return SSH_ERR_ALLOC_FAIL;
818 ssh->state->compression_in_failures++;
819 return SSH_ERR_INTERNAL_ERROR;
826 ssh_clear_newkeys(struct ssh *ssh, int mode)
828 if (ssh->kex && ssh->kex->newkeys[mode]) {
829 kex_free_newkeys(ssh->kex->newkeys[mode]);
830 ssh->kex->newkeys[mode] = NULL;
835 ssh_set_newkeys(struct ssh *ssh, int mode)
837 struct session_state *state = ssh->state;
840 struct sshcomp *comp;
841 struct sshcipher_ctx **ccp;
842 struct packet_state *ps;
843 u_int64_t *max_blocks;
847 debug2("set_newkeys: mode %d", mode);
849 if (mode == MODE_OUT) {
850 ccp = &state->send_context;
851 crypt_type = CIPHER_ENCRYPT;
853 max_blocks = &state->max_blocks_out;
855 ccp = &state->receive_context;
856 crypt_type = CIPHER_DECRYPT;
858 max_blocks = &state->max_blocks_in;
860 if (state->newkeys[mode] != NULL) {
861 debug("set_newkeys: rekeying, input %llu bytes %llu blocks, "
862 "output %llu bytes %llu blocks",
863 (unsigned long long)state->p_read.bytes,
864 (unsigned long long)state->p_read.blocks,
865 (unsigned long long)state->p_send.bytes,
866 (unsigned long long)state->p_send.blocks);
869 kex_free_newkeys(state->newkeys[mode]);
870 state->newkeys[mode] = NULL;
872 /* note that both bytes and the seqnr are not reset */
873 ps->packets = ps->blocks = 0;
874 /* move newkeys from kex to state */
875 if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
876 return SSH_ERR_INTERNAL_ERROR;
877 ssh->kex->newkeys[mode] = NULL;
878 enc = &state->newkeys[mode]->enc;
879 mac = &state->newkeys[mode]->mac;
880 comp = &state->newkeys[mode]->comp;
881 if (cipher_authlen(enc->cipher) == 0) {
882 if ((r = mac_init(mac)) != 0)
886 DBG(debug("cipher_init_context: %d", mode));
887 if ((r = cipher_init(ccp, enc->cipher, enc->key, enc->key_len,
888 enc->iv, enc->iv_len, crypt_type)) != 0)
890 if (!state->cipher_warning_done &&
891 (wmsg = cipher_warning_message(*ccp)) != NULL) {
892 error("Warning: %s", wmsg);
893 state->cipher_warning_done = 1;
895 /* Deleting the keys does not gain extra security */
896 /* explicit_bzero(enc->iv, enc->block_size);
897 explicit_bzero(enc->key, enc->key_len);
898 explicit_bzero(mac->key, mac->key_len); */
899 if ((comp->type == COMP_ZLIB ||
900 (comp->type == COMP_DELAYED &&
901 state->after_authentication)) && comp->enabled == 0) {
902 if ((r = ssh_packet_init_compression(ssh)) < 0)
904 if (mode == MODE_OUT) {
905 if ((r = start_compression_out(ssh, 6)) != 0)
908 if ((r = start_compression_in(ssh)) != 0)
914 * The 2^(blocksize*2) limit is too expensive for 3DES,
915 * so enforce a 1GB limit for small blocksizes.
916 * See RFC4344 section 3.2.
918 if (enc->block_size >= 16)
919 *max_blocks = (u_int64_t)1 << (enc->block_size*2);
921 *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
922 if (state->rekey_limit)
923 *max_blocks = MINIMUM(*max_blocks,
924 state->rekey_limit / enc->block_size);
925 debug("rekey after %llu blocks", (unsigned long long)*max_blocks);
929 #define MAX_PACKETS (1U<<31)
931 ssh_packet_need_rekeying(struct ssh *ssh, u_int outbound_packet_len)
933 struct session_state *state = ssh->state;
934 u_int32_t out_blocks;
936 /* XXX client can't cope with rekeying pre-auth */
937 if (!state->after_authentication)
940 /* Haven't keyed yet or KEX in progress. */
941 if (ssh->kex == NULL || ssh_packet_is_rekeying(ssh))
944 /* Peer can't rekey */
945 if (ssh->compat & SSH_BUG_NOREKEY)
949 * Permit one packet in or out per rekey - this allows us to
950 * make progress when rekey limits are very small.
952 if (state->p_send.packets == 0 && state->p_read.packets == 0)
955 /* Time-based rekeying */
956 if (state->rekey_interval != 0 &&
957 (int64_t)state->rekey_time + state->rekey_interval <= monotime())
961 * Always rekey when MAX_PACKETS sent in either direction
962 * As per RFC4344 section 3.1 we do this after 2^31 packets.
964 if (state->p_send.packets > MAX_PACKETS ||
965 state->p_read.packets > MAX_PACKETS)
968 /* Rekey after (cipher-specific) maxiumum blocks */
969 out_blocks = ROUNDUP(outbound_packet_len,
970 state->newkeys[MODE_OUT]->enc.block_size);
971 return (state->max_blocks_out &&
972 (state->p_send.blocks + out_blocks > state->max_blocks_out)) ||
973 (state->max_blocks_in &&
974 (state->p_read.blocks > state->max_blocks_in));
978 * Delayed compression for SSH2 is enabled after authentication:
979 * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
980 * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
983 ssh_packet_enable_delayed_compress(struct ssh *ssh)
985 struct session_state *state = ssh->state;
986 struct sshcomp *comp = NULL;
990 * Remember that we are past the authentication step, so rekeying
991 * with COMP_DELAYED will turn on compression immediately.
993 state->after_authentication = 1;
994 for (mode = 0; mode < MODE_MAX; mode++) {
995 /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
996 if (state->newkeys[mode] == NULL)
998 comp = &state->newkeys[mode]->comp;
999 if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1000 if ((r = ssh_packet_init_compression(ssh)) != 0)
1002 if (mode == MODE_OUT) {
1003 if ((r = start_compression_out(ssh, 6)) != 0)
1006 if ((r = start_compression_in(ssh)) != 0)
1015 /* Used to mute debug logging for noisy packet types */
1017 ssh_packet_log_type(u_char type)
1020 case SSH2_MSG_CHANNEL_DATA:
1021 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1022 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1030 * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1033 ssh_packet_send2_wrapped(struct ssh *ssh)
1035 struct session_state *state = ssh->state;
1036 u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1037 u_char tmp, padlen, pad = 0;
1038 u_int authlen = 0, aadlen = 0;
1040 struct sshenc *enc = NULL;
1041 struct sshmac *mac = NULL;
1042 struct sshcomp *comp = NULL;
1045 if (state->newkeys[MODE_OUT] != NULL) {
1046 enc = &state->newkeys[MODE_OUT]->enc;
1047 mac = &state->newkeys[MODE_OUT]->mac;
1048 comp = &state->newkeys[MODE_OUT]->comp;
1049 /* disable mac for authenticated encryption */
1050 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1053 block_size = enc ? enc->block_size : 8;
1054 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1056 type = (sshbuf_ptr(state->outgoing_packet))[5];
1057 if (ssh_packet_log_type(type))
1058 debug3("send packet: type %u", type);
1060 fprintf(stderr, "plain: ");
1061 sshbuf_dump(state->outgoing_packet, stderr);
1064 if (comp && comp->enabled) {
1065 len = sshbuf_len(state->outgoing_packet);
1066 /* skip header, compress only payload */
1067 if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1069 sshbuf_reset(state->compression_buffer);
1070 if ((r = compress_buffer(ssh, state->outgoing_packet,
1071 state->compression_buffer)) != 0)
1073 sshbuf_reset(state->outgoing_packet);
1074 if ((r = sshbuf_put(state->outgoing_packet,
1075 "\0\0\0\0\0", 5)) != 0 ||
1076 (r = sshbuf_putb(state->outgoing_packet,
1077 state->compression_buffer)) != 0)
1079 DBG(debug("compression: raw %d compressed %zd", len,
1080 sshbuf_len(state->outgoing_packet)));
1083 /* sizeof (packet_len + pad_len + payload) */
1084 len = sshbuf_len(state->outgoing_packet);
1087 * calc size of padding, alloc space, get random data,
1088 * minimum padding is 4 bytes
1090 len -= aadlen; /* packet length is not encrypted for EtM modes */
1091 padlen = block_size - (len % block_size);
1093 padlen += block_size;
1094 if (state->extra_pad) {
1095 tmp = state->extra_pad;
1097 ROUNDUP(state->extra_pad, block_size);
1098 /* check if roundup overflowed */
1099 if (state->extra_pad < tmp)
1100 return SSH_ERR_INVALID_ARGUMENT;
1101 tmp = (len + padlen) % state->extra_pad;
1102 /* Check whether pad calculation below will underflow */
1103 if (tmp > state->extra_pad)
1104 return SSH_ERR_INVALID_ARGUMENT;
1105 pad = state->extra_pad - tmp;
1106 DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1107 __func__, pad, len, padlen, state->extra_pad));
1110 /* Check whether padlen calculation overflowed */
1112 return SSH_ERR_INVALID_ARGUMENT; /* overflow */
1113 state->extra_pad = 0;
1115 if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1117 if (enc && !cipher_ctx_is_plaintext(state->send_context)) {
1118 /* random padding */
1119 arc4random_buf(cp, padlen);
1122 explicit_bzero(cp, padlen);
1124 /* sizeof (packet_len + pad_len + payload + padding) */
1125 len = sshbuf_len(state->outgoing_packet);
1126 cp = sshbuf_mutable_ptr(state->outgoing_packet);
1128 r = SSH_ERR_INTERNAL_ERROR;
1131 /* packet_length includes payload, padding and padding length field */
1132 POKE_U32(cp, len - 4);
1134 DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1135 len, padlen, aadlen));
1137 /* compute MAC over seqnr and packet(length fields, payload, padding) */
1138 if (mac && mac->enabled && !mac->etm) {
1139 if ((r = mac_compute(mac, state->p_send.seqnr,
1140 sshbuf_ptr(state->outgoing_packet), len,
1141 macbuf, sizeof(macbuf))) != 0)
1143 DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1145 /* encrypt packet and append to output buffer. */
1146 if ((r = sshbuf_reserve(state->output,
1147 sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1149 if ((r = cipher_crypt(state->send_context, state->p_send.seqnr, cp,
1150 sshbuf_ptr(state->outgoing_packet),
1151 len - aadlen, aadlen, authlen)) != 0)
1153 /* append unencrypted MAC */
1154 if (mac && mac->enabled) {
1156 /* EtM: compute mac over aadlen + cipher text */
1157 if ((r = mac_compute(mac, state->p_send.seqnr,
1158 cp, len, macbuf, sizeof(macbuf))) != 0)
1160 DBG(debug("done calc MAC(EtM) out #%d",
1161 state->p_send.seqnr));
1163 if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1167 fprintf(stderr, "encrypted: ");
1168 sshbuf_dump(state->output, stderr);
1170 /* increment sequence number for outgoing packets */
1171 if (++state->p_send.seqnr == 0)
1172 logit("outgoing seqnr wraps around");
1173 if (++state->p_send.packets == 0)
1174 if (!(ssh->compat & SSH_BUG_NOREKEY))
1175 return SSH_ERR_NEED_REKEY;
1176 state->p_send.blocks += len / block_size;
1177 state->p_send.bytes += len;
1178 sshbuf_reset(state->outgoing_packet);
1180 if (type == SSH2_MSG_NEWKEYS)
1181 r = ssh_set_newkeys(ssh, MODE_OUT);
1182 else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1183 r = ssh_packet_enable_delayed_compress(ssh);
1190 /* returns non-zero if the specified packet type is usec by KEX */
1192 ssh_packet_type_is_kex(u_char type)
1195 type >= SSH2_MSG_TRANSPORT_MIN &&
1196 type <= SSH2_MSG_TRANSPORT_MAX &&
1197 type != SSH2_MSG_SERVICE_REQUEST &&
1198 type != SSH2_MSG_SERVICE_ACCEPT &&
1199 type != SSH2_MSG_EXT_INFO;
1203 ssh_packet_send2(struct ssh *ssh)
1205 struct session_state *state = ssh->state;
1210 if (sshbuf_len(state->outgoing_packet) < 6)
1211 return SSH_ERR_INTERNAL_ERROR;
1212 type = sshbuf_ptr(state->outgoing_packet)[5];
1213 need_rekey = !ssh_packet_type_is_kex(type) &&
1214 ssh_packet_need_rekeying(ssh, sshbuf_len(state->outgoing_packet));
1217 * During rekeying we can only send key exchange messages.
1218 * Queue everything else.
1220 if ((need_rekey || state->rekeying) && !ssh_packet_type_is_kex(type)) {
1222 debug3("%s: rekex triggered", __func__);
1223 debug("enqueue packet: %u", type);
1224 p = calloc(1, sizeof(*p));
1226 return SSH_ERR_ALLOC_FAIL;
1228 p->payload = state->outgoing_packet;
1229 TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1230 state->outgoing_packet = sshbuf_new();
1231 if (state->outgoing_packet == NULL)
1232 return SSH_ERR_ALLOC_FAIL;
1235 * This packet triggered a rekey, so send the
1237 * NB. reenters this function via kex_start_rekex().
1239 return kex_start_rekex(ssh);
1244 /* rekeying starts with sending KEXINIT */
1245 if (type == SSH2_MSG_KEXINIT)
1246 state->rekeying = 1;
1248 if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1251 /* after a NEWKEYS message we can send the complete queue */
1252 if (type == SSH2_MSG_NEWKEYS) {
1253 state->rekeying = 0;
1254 state->rekey_time = monotime();
1255 while ((p = TAILQ_FIRST(&state->outgoing))) {
1258 * If this packet triggers a rekex, then skip the
1259 * remaining packets in the queue for now.
1260 * NB. re-enters this function via kex_start_rekex.
1262 if (ssh_packet_need_rekeying(ssh,
1263 sshbuf_len(p->payload))) {
1264 debug3("%s: queued packet triggered rekex",
1266 return kex_start_rekex(ssh);
1268 debug("dequeue packet: %u", type);
1269 sshbuf_free(state->outgoing_packet);
1270 state->outgoing_packet = p->payload;
1271 TAILQ_REMOVE(&state->outgoing, p, next);
1272 memset(p, 0, sizeof(*p));
1274 if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1282 * Waits until a packet has been received, and returns its type. Note that
1283 * no other data is processed until this returns, so this function should not
1284 * be used during the interactive session.
1288 ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1290 struct session_state *state = ssh->state;
1291 int len, r, ms_remain;
1294 struct timeval timeout, start, *timeoutp = NULL;
1296 DBG(debug("packet_read()"));
1298 setp = calloc(howmany(state->connection_in + 1,
1299 NFDBITS), sizeof(fd_mask));
1301 return SSH_ERR_ALLOC_FAIL;
1304 * Since we are blocking, ensure that all written packets have
1307 if ((r = ssh_packet_write_wait(ssh)) != 0)
1310 /* Stay in the loop until we have received a complete packet. */
1312 /* Try to read a packet from the buffer. */
1313 r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1316 /* If we got a packet, return it. */
1317 if (*typep != SSH_MSG_NONE)
1320 * Otherwise, wait for some data to arrive, add it to the
1321 * buffer, and try again.
1323 memset(setp, 0, howmany(state->connection_in + 1,
1324 NFDBITS) * sizeof(fd_mask));
1325 FD_SET(state->connection_in, setp);
1327 if (state->packet_timeout_ms > 0) {
1328 ms_remain = state->packet_timeout_ms;
1329 timeoutp = &timeout;
1331 /* Wait for some data to arrive. */
1333 if (state->packet_timeout_ms != -1) {
1334 ms_to_timeval(&timeout, ms_remain);
1335 monotime_tv(&start);
1337 if ((r = select(state->connection_in + 1, setp,
1338 NULL, NULL, timeoutp)) >= 0)
1340 if (errno != EAGAIN && errno != EINTR &&
1341 errno != EWOULDBLOCK)
1343 if (state->packet_timeout_ms == -1)
1345 ms_subtract_diff(&start, &ms_remain);
1346 if (ms_remain <= 0) {
1352 r = SSH_ERR_CONN_TIMEOUT;
1355 /* Read data from the socket. */
1356 len = read(state->connection_in, buf, sizeof(buf));
1358 r = SSH_ERR_CONN_CLOSED;
1362 r = SSH_ERR_SYSTEM_ERROR;
1366 /* Append it to the buffer. */
1367 if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1376 ssh_packet_read(struct ssh *ssh)
1381 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1382 fatal("%s: %s", __func__, ssh_err(r));
1387 * Waits until a packet has been received, verifies that its type matches
1388 * that given, and gives a fatal error and exits if there is a mismatch.
1392 ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1397 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1399 if (type != expected_type) {
1400 if ((r = sshpkt_disconnect(ssh,
1401 "Protocol error: expected packet type %d, got %d",
1402 expected_type, type)) != 0)
1404 return SSH_ERR_PROTOCOL_ERROR;
1410 ssh_packet_read_poll2_mux(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1412 struct session_state *state = ssh->state;
1418 return SSH_ERR_INTERNAL_ERROR;
1419 *typep = SSH_MSG_NONE;
1420 cp = sshbuf_ptr(state->input);
1421 if (state->packlen == 0) {
1422 if (sshbuf_len(state->input) < 4 + 1)
1423 return 0; /* packet is incomplete */
1424 state->packlen = PEEK_U32(cp);
1425 if (state->packlen < 4 + 1 ||
1426 state->packlen > PACKET_MAX_SIZE)
1427 return SSH_ERR_MESSAGE_INCOMPLETE;
1429 need = state->packlen + 4;
1430 if (sshbuf_len(state->input) < need)
1431 return 0; /* packet is incomplete */
1432 sshbuf_reset(state->incoming_packet);
1433 if ((r = sshbuf_put(state->incoming_packet, cp + 4,
1434 state->packlen)) != 0 ||
1435 (r = sshbuf_consume(state->input, need)) != 0 ||
1436 (r = sshbuf_get_u8(state->incoming_packet, NULL)) != 0 ||
1437 (r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1439 if (ssh_packet_log_type(*typep))
1440 debug3("%s: type %u", __func__, *typep);
1441 /* sshbuf_dump(state->incoming_packet, stderr); */
1442 /* reset for next packet */
1448 ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1450 struct session_state *state = ssh->state;
1453 u_int maclen, aadlen = 0, authlen = 0, block_size;
1454 struct sshenc *enc = NULL;
1455 struct sshmac *mac = NULL;
1456 struct sshcomp *comp = NULL;
1460 return ssh_packet_read_poll2_mux(ssh, typep, seqnr_p);
1462 *typep = SSH_MSG_NONE;
1464 if (state->packet_discard)
1467 if (state->newkeys[MODE_IN] != NULL) {
1468 enc = &state->newkeys[MODE_IN]->enc;
1469 mac = &state->newkeys[MODE_IN]->mac;
1470 comp = &state->newkeys[MODE_IN]->comp;
1471 /* disable mac for authenticated encryption */
1472 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1475 maclen = mac && mac->enabled ? mac->mac_len : 0;
1476 block_size = enc ? enc->block_size : 8;
1477 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1479 if (aadlen && state->packlen == 0) {
1480 if (cipher_get_length(state->receive_context,
1481 &state->packlen, state->p_read.seqnr,
1482 sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1484 if (state->packlen < 1 + 4 ||
1485 state->packlen > PACKET_MAX_SIZE) {
1487 sshbuf_dump(state->input, stderr);
1489 logit("Bad packet length %u.", state->packlen);
1490 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1492 return SSH_ERR_CONN_CORRUPT;
1494 sshbuf_reset(state->incoming_packet);
1495 } else if (state->packlen == 0) {
1497 * check if input size is less than the cipher block size,
1498 * decrypt first block and extract length of incoming packet
1500 if (sshbuf_len(state->input) < block_size)
1502 sshbuf_reset(state->incoming_packet);
1503 if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1506 if ((r = cipher_crypt(state->receive_context,
1507 state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1508 block_size, 0, 0)) != 0)
1510 state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1511 if (state->packlen < 1 + 4 ||
1512 state->packlen > PACKET_MAX_SIZE) {
1514 fprintf(stderr, "input: \n");
1515 sshbuf_dump(state->input, stderr);
1516 fprintf(stderr, "incoming_packet: \n");
1517 sshbuf_dump(state->incoming_packet, stderr);
1519 logit("Bad packet length %u.", state->packlen);
1520 return ssh_packet_start_discard(ssh, enc, mac, 0,
1523 if ((r = sshbuf_consume(state->input, block_size)) != 0)
1526 DBG(debug("input: packet len %u", state->packlen+4));
1529 /* only the payload is encrypted */
1530 need = state->packlen;
1533 * the payload size and the payload are encrypted, but we
1534 * have a partial packet of block_size bytes
1536 need = 4 + state->packlen - block_size;
1538 DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1539 " aadlen %d", block_size, need, maclen, authlen, aadlen));
1540 if (need % block_size != 0) {
1541 logit("padding error: need %d block %d mod %d",
1542 need, block_size, need % block_size);
1543 return ssh_packet_start_discard(ssh, enc, mac, 0,
1544 PACKET_MAX_SIZE - block_size);
1547 * check if the entire packet has been received and
1548 * decrypt into incoming_packet:
1549 * 'aadlen' bytes are unencrypted, but authenticated.
1550 * 'need' bytes are encrypted, followed by either
1551 * 'authlen' bytes of authentication tag or
1552 * 'maclen' bytes of message authentication code.
1554 if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1555 return 0; /* packet is incomplete */
1557 fprintf(stderr, "read_poll enc/full: ");
1558 sshbuf_dump(state->input, stderr);
1560 /* EtM: check mac over encrypted input */
1561 if (mac && mac->enabled && mac->etm) {
1562 if ((r = mac_check(mac, state->p_read.seqnr,
1563 sshbuf_ptr(state->input), aadlen + need,
1564 sshbuf_ptr(state->input) + aadlen + need + authlen,
1566 if (r == SSH_ERR_MAC_INVALID)
1567 logit("Corrupted MAC on input.");
1571 if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1574 if ((r = cipher_crypt(state->receive_context, state->p_read.seqnr, cp,
1575 sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1577 if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1579 if (mac && mac->enabled) {
1580 /* Not EtM: check MAC over cleartext */
1581 if (!mac->etm && (r = mac_check(mac, state->p_read.seqnr,
1582 sshbuf_ptr(state->incoming_packet),
1583 sshbuf_len(state->incoming_packet),
1584 sshbuf_ptr(state->input), maclen)) != 0) {
1585 if (r != SSH_ERR_MAC_INVALID)
1587 logit("Corrupted MAC on input.");
1588 if (need + block_size > PACKET_MAX_SIZE)
1589 return SSH_ERR_INTERNAL_ERROR;
1590 return ssh_packet_start_discard(ssh, enc, mac,
1591 sshbuf_len(state->incoming_packet),
1592 PACKET_MAX_SIZE - need - block_size);
1594 /* Remove MAC from input buffer */
1595 DBG(debug("MAC #%d ok", state->p_read.seqnr));
1596 if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1599 if (seqnr_p != NULL)
1600 *seqnr_p = state->p_read.seqnr;
1601 if (++state->p_read.seqnr == 0)
1602 logit("incoming seqnr wraps around");
1603 if (++state->p_read.packets == 0)
1604 if (!(ssh->compat & SSH_BUG_NOREKEY))
1605 return SSH_ERR_NEED_REKEY;
1606 state->p_read.blocks += (state->packlen + 4) / block_size;
1607 state->p_read.bytes += state->packlen + 4;
1610 padlen = sshbuf_ptr(state->incoming_packet)[4];
1611 DBG(debug("input: padlen %d", padlen));
1613 if ((r = sshpkt_disconnect(ssh,
1614 "Corrupted padlen %d on input.", padlen)) != 0 ||
1615 (r = ssh_packet_write_wait(ssh)) != 0)
1617 return SSH_ERR_CONN_CORRUPT;
1620 /* skip packet size + padlen, discard padding */
1621 if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1622 ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1625 DBG(debug("input: len before de-compress %zd",
1626 sshbuf_len(state->incoming_packet)));
1627 if (comp && comp->enabled) {
1628 sshbuf_reset(state->compression_buffer);
1629 if ((r = uncompress_buffer(ssh, state->incoming_packet,
1630 state->compression_buffer)) != 0)
1632 sshbuf_reset(state->incoming_packet);
1633 if ((r = sshbuf_putb(state->incoming_packet,
1634 state->compression_buffer)) != 0)
1636 DBG(debug("input: len after de-compress %zd",
1637 sshbuf_len(state->incoming_packet)));
1640 * get packet type, implies consume.
1641 * return length of payload (without type field)
1643 if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1645 if (ssh_packet_log_type(*typep))
1646 debug3("receive packet: type %u", *typep);
1647 if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1648 if ((r = sshpkt_disconnect(ssh,
1649 "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1650 (r = ssh_packet_write_wait(ssh)) != 0)
1652 return SSH_ERR_PROTOCOL_ERROR;
1654 if (state->hook_in != NULL &&
1655 (r = state->hook_in(ssh, state->incoming_packet, typep,
1656 state->hook_in_ctx)) != 0)
1658 if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1659 r = ssh_packet_enable_delayed_compress(ssh);
1663 fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1664 sshbuf_dump(state->incoming_packet, stderr);
1666 /* reset for next packet */
1669 /* do we need to rekey? */
1670 if (ssh_packet_need_rekeying(ssh, 0)) {
1671 debug3("%s: rekex triggered", __func__);
1672 if ((r = kex_start_rekex(ssh)) != 0)
1680 ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1682 struct session_state *state = ssh->state;
1683 u_int reason, seqnr;
1689 r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1693 state->keep_alive_timeouts = 0;
1694 DBG(debug("received packet type %d", *typep));
1697 case SSH2_MSG_IGNORE:
1698 debug3("Received SSH2_MSG_IGNORE");
1700 case SSH2_MSG_DEBUG:
1701 if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1702 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1703 (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1707 debug("Remote: %.900s", msg);
1710 case SSH2_MSG_DISCONNECT:
1711 if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1712 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1714 /* Ignore normal client exit notifications */
1715 do_log2(ssh->state->server_side &&
1716 reason == SSH2_DISCONNECT_BY_APPLICATION ?
1717 SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1718 "Received disconnect from %s port %d:"
1719 "%u: %.400s", ssh_remote_ipaddr(ssh),
1720 ssh_remote_port(ssh), reason, msg);
1722 return SSH_ERR_DISCONNECTED;
1723 case SSH2_MSG_UNIMPLEMENTED:
1724 if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1726 debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1736 * Buffers the given amount of input characters. This is intended to be used
1737 * together with packet_read_poll.
1741 ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1743 struct session_state *state = ssh->state;
1746 if (state->packet_discard) {
1747 state->keep_alive_timeouts = 0; /* ?? */
1748 if (len >= state->packet_discard) {
1749 if ((r = ssh_packet_stop_discard(ssh)) != 0)
1752 state->packet_discard -= len;
1755 if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1762 ssh_packet_remaining(struct ssh *ssh)
1764 return sshbuf_len(ssh->state->incoming_packet);
1768 * Sends a diagnostic message from the server to the client. This message
1769 * can be sent at any time (but not while constructing another message). The
1770 * message is printed immediately, but only if the client is being executed
1771 * in verbose mode. These messages are primarily intended to ease debugging
1772 * authentication problems. The length of the formatted message must not
1773 * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1776 ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1782 if ((ssh->compat & SSH_BUG_DEBUG))
1785 va_start(args, fmt);
1786 vsnprintf(buf, sizeof(buf), fmt, args);
1789 debug3("sending debug message: %s", buf);
1791 if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1792 (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1793 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1794 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1795 (r = sshpkt_send(ssh)) != 0 ||
1796 (r = ssh_packet_write_wait(ssh)) != 0)
1797 fatal("%s: %s", __func__, ssh_err(r));
1801 sshpkt_fmt_connection_id(struct ssh *ssh, char *s, size_t l)
1803 snprintf(s, l, "%.200s%s%s port %d",
1804 ssh->log_preamble ? ssh->log_preamble : "",
1805 ssh->log_preamble ? " " : "",
1806 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1810 * Pretty-print connection-terminating errors and exit.
1813 sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1815 char remote_id[512];
1817 sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1820 case SSH_ERR_CONN_CLOSED:
1821 ssh_packet_clear_keys(ssh);
1822 logdie("Connection closed by %s", remote_id);
1823 case SSH_ERR_CONN_TIMEOUT:
1824 ssh_packet_clear_keys(ssh);
1825 logdie("Connection %s %s timed out",
1826 ssh->state->server_side ? "from" : "to", remote_id);
1827 case SSH_ERR_DISCONNECTED:
1828 ssh_packet_clear_keys(ssh);
1829 logdie("Disconnected from %s", remote_id);
1830 case SSH_ERR_SYSTEM_ERROR:
1831 if (errno == ECONNRESET) {
1832 ssh_packet_clear_keys(ssh);
1833 logdie("Connection reset by %s", remote_id);
1836 case SSH_ERR_NO_CIPHER_ALG_MATCH:
1837 case SSH_ERR_NO_MAC_ALG_MATCH:
1838 case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1839 case SSH_ERR_NO_KEX_ALG_MATCH:
1840 case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1841 if (ssh && ssh->kex && ssh->kex->failed_choice) {
1842 ssh_packet_clear_keys(ssh);
1843 logdie("Unable to negotiate with %s: %s. "
1844 "Their offer: %s", remote_id, ssh_err(r),
1845 ssh->kex->failed_choice);
1849 ssh_packet_clear_keys(ssh);
1850 logdie("%s%sConnection %s %s: %s",
1851 tag != NULL ? tag : "", tag != NULL ? ": " : "",
1852 ssh->state->server_side ? "from" : "to",
1853 remote_id, ssh_err(r));
1858 * Logs the error plus constructs and sends a disconnect packet, closes the
1859 * connection, and exits. This function never returns. The error message
1860 * should not contain a newline. The length of the formatted message must
1861 * not exceed 1024 bytes.
1864 ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1866 char buf[1024], remote_id[512];
1868 static int disconnecting = 0;
1871 if (disconnecting) /* Guard against recursive invocations. */
1872 fatal("packet_disconnect called recursively.");
1876 * Format the message. Note that the caller must make sure the
1877 * message is of limited size.
1879 sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1880 va_start(args, fmt);
1881 vsnprintf(buf, sizeof(buf), fmt, args);
1884 /* Display the error locally */
1885 logit("Disconnecting %s: %.100s", remote_id, buf);
1888 * Send the disconnect message to the other side, and wait
1889 * for it to get sent.
1891 if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1892 sshpkt_fatal(ssh, __func__, r);
1894 if ((r = ssh_packet_write_wait(ssh)) != 0)
1895 sshpkt_fatal(ssh, __func__, r);
1897 /* Close the connection. */
1898 ssh_packet_close(ssh);
1903 * Checks if there is any buffered output, and tries to write some of
1907 ssh_packet_write_poll(struct ssh *ssh)
1909 struct session_state *state = ssh->state;
1910 int len = sshbuf_len(state->output);
1914 len = write(state->connection_out,
1915 sshbuf_ptr(state->output), len);
1917 if (errno == EINTR || errno == EAGAIN ||
1918 errno == EWOULDBLOCK)
1920 return SSH_ERR_SYSTEM_ERROR;
1923 return SSH_ERR_CONN_CLOSED;
1924 if ((r = sshbuf_consume(state->output, len)) != 0)
1931 * Calls packet_write_poll repeatedly until all pending output data has been
1935 ssh_packet_write_wait(struct ssh *ssh)
1938 int ret, r, ms_remain = 0;
1939 struct timeval start, timeout, *timeoutp = NULL;
1940 struct session_state *state = ssh->state;
1942 setp = calloc(howmany(state->connection_out + 1,
1943 NFDBITS), sizeof(fd_mask));
1945 return SSH_ERR_ALLOC_FAIL;
1946 if ((r = ssh_packet_write_poll(ssh)) != 0) {
1950 while (ssh_packet_have_data_to_write(ssh)) {
1951 memset(setp, 0, howmany(state->connection_out + 1,
1952 NFDBITS) * sizeof(fd_mask));
1953 FD_SET(state->connection_out, setp);
1955 if (state->packet_timeout_ms > 0) {
1956 ms_remain = state->packet_timeout_ms;
1957 timeoutp = &timeout;
1960 if (state->packet_timeout_ms != -1) {
1961 ms_to_timeval(&timeout, ms_remain);
1962 monotime_tv(&start);
1964 if ((ret = select(state->connection_out + 1,
1965 NULL, setp, NULL, timeoutp)) >= 0)
1967 if (errno != EAGAIN && errno != EINTR &&
1968 errno != EWOULDBLOCK)
1970 if (state->packet_timeout_ms == -1)
1972 ms_subtract_diff(&start, &ms_remain);
1973 if (ms_remain <= 0) {
1980 return SSH_ERR_CONN_TIMEOUT;
1982 if ((r = ssh_packet_write_poll(ssh)) != 0) {
1991 /* Returns true if there is buffered data to write to the connection. */
1994 ssh_packet_have_data_to_write(struct ssh *ssh)
1996 return sshbuf_len(ssh->state->output) != 0;
1999 /* Returns true if there is not too much data to write to the connection. */
2002 ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
2004 if (ssh->state->interactive_mode)
2005 return sshbuf_len(ssh->state->output) < 16384;
2007 return sshbuf_len(ssh->state->output) < 128 * 1024;
2011 ssh_packet_set_tos(struct ssh *ssh, int tos)
2013 #ifndef IP_TOS_IS_BROKEN
2014 if (!ssh_packet_connection_is_on_socket(ssh) || tos == INT_MAX)
2016 switch (ssh_packet_connection_af(ssh)) {
2019 debug3("%s: set IP_TOS 0x%02x", __func__, tos);
2020 if (setsockopt(ssh->state->connection_in,
2021 IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2022 error("setsockopt IP_TOS %d: %.100s:",
2023 tos, strerror(errno));
2025 # endif /* IP_TOS */
2028 debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
2029 if (setsockopt(ssh->state->connection_in,
2030 IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2031 error("setsockopt IPV6_TCLASS %d: %.100s:",
2032 tos, strerror(errno));
2034 # endif /* IPV6_TCLASS */
2036 #endif /* IP_TOS_IS_BROKEN */
2039 /* Informs that the current session is interactive. Sets IP flags for that. */
2042 ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
2044 struct session_state *state = ssh->state;
2046 if (state->set_interactive_called)
2048 state->set_interactive_called = 1;
2050 /* Record that we are in interactive mode. */
2051 state->interactive_mode = interactive;
2053 /* Only set socket options if using a socket. */
2054 if (!ssh_packet_connection_is_on_socket(ssh))
2056 set_nodelay(state->connection_in);
2057 ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2061 /* Returns true if the current connection is interactive. */
2064 ssh_packet_is_interactive(struct ssh *ssh)
2066 return ssh->state->interactive_mode;
2070 ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
2072 struct session_state *state = ssh->state;
2074 if (state->set_maxsize_called) {
2075 logit("packet_set_maxsize: called twice: old %d new %d",
2076 state->max_packet_size, s);
2079 if (s < 4 * 1024 || s > 1024 * 1024) {
2080 logit("packet_set_maxsize: bad size %d", s);
2083 state->set_maxsize_called = 1;
2084 debug("packet_set_maxsize: setting to %d", s);
2085 state->max_packet_size = s;
2090 ssh_packet_inc_alive_timeouts(struct ssh *ssh)
2092 return ++ssh->state->keep_alive_timeouts;
2096 ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
2098 ssh->state->keep_alive_timeouts = ka;
2102 ssh_packet_get_maxsize(struct ssh *ssh)
2104 return ssh->state->max_packet_size;
2108 ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, u_int32_t seconds)
2110 debug3("rekey after %llu bytes, %u seconds", (unsigned long long)bytes,
2111 (unsigned int)seconds);
2112 ssh->state->rekey_limit = bytes;
2113 ssh->state->rekey_interval = seconds;
2117 ssh_packet_get_rekey_timeout(struct ssh *ssh)
2121 seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
2123 return (seconds <= 0 ? 1 : seconds);
2127 ssh_packet_set_server(struct ssh *ssh)
2129 ssh->state->server_side = 1;
2133 ssh_packet_set_authenticated(struct ssh *ssh)
2135 ssh->state->after_authentication = 1;
2139 ssh_packet_get_input(struct ssh *ssh)
2141 return (void *)ssh->state->input;
2145 ssh_packet_get_output(struct ssh *ssh)
2147 return (void *)ssh->state->output;
2150 /* Reset after_authentication and reset compression in post-auth privsep */
2152 ssh_packet_set_postauth(struct ssh *ssh)
2156 debug("%s: called", __func__);
2157 /* This was set in net child, but is not visible in user child */
2158 ssh->state->after_authentication = 1;
2159 ssh->state->rekeying = 0;
2160 if ((r = ssh_packet_enable_delayed_compress(ssh)) != 0)
2165 /* Packet state (de-)serialization for privsep */
2167 /* turn kex into a blob for packet state serialization */
2169 kex_to_blob(struct sshbuf *m, struct kex *kex)
2173 if ((r = sshbuf_put_string(m, kex->session_id,
2174 kex->session_id_len)) != 0 ||
2175 (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2176 (r = sshbuf_put_cstring(m, kex->hostkey_alg)) != 0 ||
2177 (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2178 (r = sshbuf_put_u32(m, kex->hostkey_nid)) != 0 ||
2179 (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2180 (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2181 (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2182 (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2183 (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2184 (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2189 /* turn key exchange results into a blob for packet state serialization */
2191 newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2194 struct sshcipher_ctx *cc;
2195 struct sshcomp *comp;
2198 struct newkeys *newkey;
2201 if ((newkey = ssh->state->newkeys[mode]) == NULL)
2202 return SSH_ERR_INTERNAL_ERROR;
2205 comp = &newkey->comp;
2206 cc = (mode == MODE_OUT) ? ssh->state->send_context :
2207 ssh->state->receive_context;
2208 if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2210 if ((b = sshbuf_new()) == NULL)
2211 return SSH_ERR_ALLOC_FAIL;
2212 if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2213 (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2214 (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2215 (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2216 (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2218 if (cipher_authlen(enc->cipher) == 0) {
2219 if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2220 (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2221 (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2224 if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2225 (r = sshbuf_put_cstring(b, comp->name)) != 0)
2227 r = sshbuf_put_stringb(m, b);
2233 /* serialize packet state into a blob */
2235 ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2237 struct session_state *state = ssh->state;
2240 if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2241 (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2242 (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
2243 (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
2244 (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
2245 (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2246 (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2247 (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2248 (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2249 (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2250 (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2251 (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2252 (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0 ||
2253 (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2254 (r = sshbuf_put_stringb(m, state->output)) != 0)
2260 /* restore key exchange results from blob for packet state de-serialization */
2262 newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2264 struct sshbuf *b = NULL;
2265 struct sshcomp *comp;
2268 struct newkeys *newkey = NULL;
2269 size_t keylen, ivlen, maclen;
2272 if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2273 r = SSH_ERR_ALLOC_FAIL;
2276 if ((r = sshbuf_froms(m, &b)) != 0)
2279 sshbuf_dump(b, stderr);
2283 comp = &newkey->comp;
2285 if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2286 (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2287 (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2288 (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2289 (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2291 if ((enc->cipher = cipher_by_name(enc->name)) == NULL) {
2292 r = SSH_ERR_INVALID_FORMAT;
2295 if (cipher_authlen(enc->cipher) == 0) {
2296 if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2298 if ((r = mac_setup(mac, mac->name)) != 0)
2300 if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2301 (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2303 if (maclen > mac->key_len) {
2304 r = SSH_ERR_INVALID_FORMAT;
2307 mac->key_len = maclen;
2309 if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2310 (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2312 if (sshbuf_len(b) != 0) {
2313 r = SSH_ERR_INVALID_FORMAT;
2316 enc->key_len = keylen;
2317 enc->iv_len = ivlen;
2318 ssh->kex->newkeys[mode] = newkey;
2327 /* restore kex from blob for packet state de-serialization */
2329 kex_from_blob(struct sshbuf *m, struct kex **kexp)
2334 if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2335 (kex->my = sshbuf_new()) == NULL ||
2336 (kex->peer = sshbuf_new()) == NULL) {
2337 r = SSH_ERR_ALLOC_FAIL;
2340 if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2341 (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2342 (r = sshbuf_get_cstring(m, &kex->hostkey_alg, NULL)) != 0 ||
2343 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2344 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_nid)) != 0 ||
2345 (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2346 (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2347 (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2348 (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2349 (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2350 (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2356 if (r != 0 || kexp == NULL) {
2358 sshbuf_free(kex->my);
2359 sshbuf_free(kex->peer);
2371 * Restore packet state from content of blob 'm' (de-serialization).
2372 * Note that 'm' will be partially consumed on parsing or any other errors.
2375 ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2377 struct session_state *state = ssh->state;
2378 const u_char *input, *output;
2382 if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2383 (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2384 (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
2385 (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
2386 (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
2387 (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2388 (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2389 (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2390 (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2391 (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2392 (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2393 (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2394 (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2397 * We set the time here so that in post-auth privsep slave we
2398 * count from the completion of the authentication.
2400 state->rekey_time = monotime();
2401 /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2402 if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2403 (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2406 if ((r = ssh_packet_set_postauth(ssh)) != 0)
2409 sshbuf_reset(state->input);
2410 sshbuf_reset(state->output);
2411 if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2412 (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2413 (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2414 (r = sshbuf_put(state->output, output, olen)) != 0)
2418 return SSH_ERR_INVALID_FORMAT;
2419 debug3("%s: done", __func__);
2425 /* put data to the outgoing packet */
2428 sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2430 return sshbuf_put(ssh->state->outgoing_packet, v, len);
2434 sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2436 return sshbuf_putb(ssh->state->outgoing_packet, b);
2440 sshpkt_put_u8(struct ssh *ssh, u_char val)
2442 return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2446 sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2448 return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2452 sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2454 return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2458 sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2460 return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2464 sshpkt_put_cstring(struct ssh *ssh, const void *v)
2466 return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2470 sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2472 return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2476 #ifdef OPENSSL_HAS_ECC
2478 sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2480 return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2482 #endif /* OPENSSL_HAS_ECC */
2486 sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2488 return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2490 #endif /* WITH_OPENSSL */
2492 /* fetch data from the incoming packet */
2495 sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2497 return sshbuf_get(ssh->state->incoming_packet, valp, len);
2501 sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2503 return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2507 sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2509 return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2513 sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2515 return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2519 sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2521 return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2525 sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2527 return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2531 sshpkt_peek_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2533 return sshbuf_peek_string_direct(ssh->state->incoming_packet, valp, lenp);
2537 sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2539 return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2543 #ifdef OPENSSL_HAS_ECC
2545 sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2547 return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2549 #endif /* OPENSSL_HAS_ECC */
2553 sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2555 return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2557 #endif /* WITH_OPENSSL */
2560 sshpkt_get_end(struct ssh *ssh)
2562 if (sshbuf_len(ssh->state->incoming_packet) > 0)
2563 return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2568 sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2571 *lenp = sshbuf_len(ssh->state->incoming_packet);
2572 return sshbuf_ptr(ssh->state->incoming_packet);
2575 /* start a new packet */
2578 sshpkt_start(struct ssh *ssh, u_char type)
2580 u_char buf[6]; /* u32 packet length, u8 pad len, u8 type */
2582 DBG(debug("packet_start[%d]", type));
2583 memset(buf, 0, sizeof(buf));
2584 buf[sizeof(buf) - 1] = type;
2585 sshbuf_reset(ssh->state->outgoing_packet);
2586 return sshbuf_put(ssh->state->outgoing_packet, buf, sizeof(buf));
2590 ssh_packet_send_mux(struct ssh *ssh)
2592 struct session_state *state = ssh->state;
2598 return SSH_ERR_INTERNAL_ERROR;
2599 len = sshbuf_len(state->outgoing_packet);
2601 return SSH_ERR_INTERNAL_ERROR;
2602 cp = sshbuf_mutable_ptr(state->outgoing_packet);
2604 if (ssh_packet_log_type(type))
2605 debug3("%s: type %u", __func__, type);
2606 /* drop everything, but the connection protocol */
2607 if (type >= SSH2_MSG_CONNECTION_MIN &&
2608 type <= SSH2_MSG_CONNECTION_MAX) {
2609 POKE_U32(cp, len - 4);
2610 if ((r = sshbuf_putb(state->output,
2611 state->outgoing_packet)) != 0)
2613 /* sshbuf_dump(state->output, stderr); */
2615 sshbuf_reset(state->outgoing_packet);
2620 * 9.2. Ignored Data Message
2622 * byte SSH_MSG_IGNORE
2625 * All implementations MUST understand (and ignore) this message at any
2626 * time (after receiving the protocol version). No implementation is
2627 * required to send them. This message can be used as an additional
2628 * protection measure against advanced traffic analysis techniques.
2631 sshpkt_msg_ignore(struct ssh *ssh, u_int nbytes)
2637 if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
2638 (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2640 for (i = 0; i < nbytes; i++) {
2643 if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2653 sshpkt_send(struct ssh *ssh)
2655 if (ssh->state && ssh->state->mux)
2656 return ssh_packet_send_mux(ssh);
2657 return ssh_packet_send2(ssh);
2661 sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2667 va_start(args, fmt);
2668 vsnprintf(buf, sizeof(buf), fmt, args);
2671 if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2672 (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2673 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2674 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2675 (r = sshpkt_send(ssh)) != 0)
2680 /* roundup current message to pad bytes */
2682 sshpkt_add_padding(struct ssh *ssh, u_char pad)
2684 ssh->state->extra_pad = pad;