1 /* $OpenBSD: packet.c,v 1.283 2019/03/01 03:29:32 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 * 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>
103 #define PACKET_MAX_SIZE (256 * 1024)
105 struct packet_state {
113 TAILQ_ENTRY(packet) next;
115 struct sshbuf *payload;
118 struct session_state {
120 * This variable contains the file descriptors used for
121 * communicating with the other side. connection_in is used for
122 * reading; connection_out for writing. These can be the same
123 * descriptor, in which case it is assumed to be a socket.
128 /* Protocol flags for the remote side. */
129 u_int remote_protocol_flags;
131 /* Encryption context for receiving data. Only used for decryption. */
132 struct sshcipher_ctx *receive_context;
134 /* Encryption context for sending data. Only used for encryption. */
135 struct sshcipher_ctx *send_context;
137 /* Buffer for raw input data from the socket. */
138 struct sshbuf *input;
140 /* Buffer for raw output data going to the socket. */
141 struct sshbuf *output;
143 /* Buffer for the partial outgoing packet being constructed. */
144 struct sshbuf *outgoing_packet;
146 /* Buffer for the incoming packet currently being processed. */
147 struct sshbuf *incoming_packet;
149 /* Scratch buffer for packet compression/decompression. */
150 struct sshbuf *compression_buffer;
152 /* Incoming/outgoing compression dictionaries */
153 z_stream compression_in_stream;
154 z_stream compression_out_stream;
155 int compression_in_started;
156 int compression_out_started;
157 int compression_in_failures;
158 int compression_out_failures;
160 /* default maximum packet size */
161 u_int max_packet_size;
163 /* Flag indicating whether this module has been initialized. */
166 /* Set to true if the connection is interactive. */
167 int interactive_mode;
169 /* Set to true if we are the server side. */
172 /* Set to true if we are authenticated. */
173 int after_authentication;
175 int keep_alive_timeouts;
177 /* The maximum time that we will wait to send or receive a packet */
178 int packet_timeout_ms;
180 /* Session key information for Encryption and MAC */
181 struct newkeys *newkeys[MODE_MAX];
182 struct packet_state p_read, p_send;
184 /* Volume-based rekeying */
185 u_int64_t max_blocks_in, max_blocks_out, rekey_limit;
187 /* Time-based rekeying */
188 u_int32_t rekey_interval; /* how often in seconds */
189 time_t rekey_time; /* time of last rekeying */
191 /* roundup current message to extra_pad bytes */
194 /* XXX discard incoming data after MAC error */
195 u_int packet_discard;
196 size_t packet_discard_mac_already;
197 struct sshmac *packet_discard_mac;
199 /* Used in packet_read_poll2() */
202 /* Used in packet_send2 */
205 /* Used in ssh_packet_send_mux() */
208 /* Used in packet_set_interactive */
209 int set_interactive_called;
211 /* Used in packet_set_maxsize */
212 int set_maxsize_called;
214 /* One-off warning about weak ciphers */
215 int cipher_warning_done;
217 /* Hook for fuzzing inbound packets */
218 ssh_packet_hook_fn *hook_in;
221 TAILQ_HEAD(, packet) outgoing;
225 ssh_alloc_session_state(void)
227 struct ssh *ssh = NULL;
228 struct session_state *state = NULL;
230 if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
231 (state = calloc(1, sizeof(*state))) == NULL ||
232 (ssh->kex = kex_new()) == 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.
260 sshbuf_free(state->input);
261 sshbuf_free(state->output);
262 sshbuf_free(state->incoming_packet);
263 sshbuf_free(state->outgoing_packet);
270 ssh_packet_set_input_hook(struct ssh *ssh, ssh_packet_hook_fn *hook, void *ctx)
272 ssh->state->hook_in = hook;
273 ssh->state->hook_in_ctx = ctx;
276 /* Returns nonzero if rekeying is in progress */
278 ssh_packet_is_rekeying(struct ssh *ssh)
280 return ssh->state->rekeying || ssh->kex->done == 0;
284 * Sets the descriptors used for communication.
287 ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
289 struct session_state *state;
290 const struct sshcipher *none = cipher_by_name("none");
294 error("%s: cannot load cipher 'none'", __func__);
298 ssh = ssh_alloc_session_state();
300 error("%s: cound not allocate state", __func__);
304 state->connection_in = fd_in;
305 state->connection_out = fd_out;
306 if ((r = cipher_init(&state->send_context, none,
307 (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
308 (r = cipher_init(&state->receive_context, none,
309 (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
310 error("%s: cipher_init failed: %s", __func__, ssh_err(r));
311 free(ssh); /* XXX need ssh_free_session_state? */
314 state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
316 * Cache the IP address of the remote connection for use in error
317 * messages that might be generated after the connection has closed.
319 (void)ssh_remote_ipaddr(ssh);
324 ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
326 struct session_state *state = ssh->state;
328 if (timeout <= 0 || count <= 0) {
329 state->packet_timeout_ms = -1;
332 if ((INT_MAX / 1000) / count < timeout)
333 state->packet_timeout_ms = INT_MAX;
335 state->packet_timeout_ms = timeout * count * 1000;
339 ssh_packet_set_mux(struct ssh *ssh)
342 ssh->state->rekeying = 0;
346 ssh_packet_get_mux(struct ssh *ssh)
348 return ssh->state->mux;
352 ssh_packet_set_log_preamble(struct ssh *ssh, const char *fmt, ...)
357 free(ssh->log_preamble);
359 ssh->log_preamble = NULL;
362 r = vasprintf(&ssh->log_preamble, fmt, args);
364 if (r < 0 || ssh->log_preamble == NULL)
365 return SSH_ERR_ALLOC_FAIL;
371 ssh_packet_stop_discard(struct ssh *ssh)
373 struct session_state *state = ssh->state;
376 if (state->packet_discard_mac) {
378 size_t dlen = PACKET_MAX_SIZE;
380 if (dlen > state->packet_discard_mac_already)
381 dlen -= state->packet_discard_mac_already;
382 memset(buf, 'a', sizeof(buf));
383 while (sshbuf_len(state->incoming_packet) < dlen)
384 if ((r = sshbuf_put(state->incoming_packet, buf,
387 (void) mac_compute(state->packet_discard_mac,
389 sshbuf_ptr(state->incoming_packet), dlen,
392 logit("Finished discarding for %.200s port %d",
393 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
394 return SSH_ERR_MAC_INVALID;
398 ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
399 struct sshmac *mac, size_t mac_already, u_int discard)
401 struct session_state *state = ssh->state;
404 if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
405 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
407 return SSH_ERR_MAC_INVALID;
410 * Record number of bytes over which the mac has already
411 * been computed in order to minimize timing attacks.
413 if (mac && mac->enabled) {
414 state->packet_discard_mac = mac;
415 state->packet_discard_mac_already = mac_already;
417 if (sshbuf_len(state->input) >= discard)
418 return ssh_packet_stop_discard(ssh);
419 state->packet_discard = discard - sshbuf_len(state->input);
423 /* Returns 1 if remote host is connected via socket, 0 if not. */
426 ssh_packet_connection_is_on_socket(struct ssh *ssh)
428 struct session_state *state;
429 struct sockaddr_storage from, to;
430 socklen_t fromlen, tolen;
432 if (ssh == NULL || ssh->state == NULL)
436 if (state->connection_in == -1 || state->connection_out == -1)
438 /* filedescriptors in and out are the same, so it's a socket */
439 if (state->connection_in == state->connection_out)
441 fromlen = sizeof(from);
442 memset(&from, 0, sizeof(from));
443 if (getpeername(state->connection_in, (struct sockaddr *)&from,
447 memset(&to, 0, sizeof(to));
448 if (getpeername(state->connection_out, (struct sockaddr *)&to,
451 if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
453 if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
459 ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
462 *ibytes = ssh->state->p_read.bytes;
464 *obytes = ssh->state->p_send.bytes;
468 ssh_packet_connection_af(struct ssh *ssh)
470 struct sockaddr_storage to;
471 socklen_t tolen = sizeof(to);
473 memset(&to, 0, sizeof(to));
474 if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
478 if (to.ss_family == AF_INET6 &&
479 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr))
485 /* Sets the connection into non-blocking mode. */
488 ssh_packet_set_nonblocking(struct ssh *ssh)
490 /* Set the socket into non-blocking mode. */
491 set_nonblock(ssh->state->connection_in);
493 if (ssh->state->connection_out != ssh->state->connection_in)
494 set_nonblock(ssh->state->connection_out);
497 /* Returns the socket used for reading. */
500 ssh_packet_get_connection_in(struct ssh *ssh)
502 return ssh->state->connection_in;
505 /* Returns the descriptor used for writing. */
508 ssh_packet_get_connection_out(struct ssh *ssh)
510 return ssh->state->connection_out;
514 * Returns the IP-address of the remote host as a string. The returned
515 * string must not be freed.
519 ssh_remote_ipaddr(struct ssh *ssh)
523 /* Check whether we have cached the ipaddr. */
524 if (ssh->remote_ipaddr == NULL) {
525 if (ssh_packet_connection_is_on_socket(ssh)) {
526 sock = ssh->state->connection_in;
527 ssh->remote_ipaddr = get_peer_ipaddr(sock);
528 ssh->remote_port = get_peer_port(sock);
529 ssh->local_ipaddr = get_local_ipaddr(sock);
530 ssh->local_port = get_local_port(sock);
532 ssh->remote_ipaddr = strdup("UNKNOWN");
533 ssh->remote_port = 65535;
534 ssh->local_ipaddr = strdup("UNKNOWN");
535 ssh->local_port = 65535;
538 return ssh->remote_ipaddr;
541 /* Returns the port number of the remote host. */
544 ssh_remote_port(struct ssh *ssh)
546 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
547 return ssh->remote_port;
551 * Returns the IP-address of the local host as a string. The returned
552 * string must not be freed.
556 ssh_local_ipaddr(struct ssh *ssh)
558 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
559 return ssh->local_ipaddr;
562 /* Returns the port number of the local host. */
565 ssh_local_port(struct ssh *ssh)
567 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
568 return ssh->local_port;
571 /* Returns the routing domain of the input socket, or NULL if unavailable */
573 ssh_packet_rdomain_in(struct ssh *ssh)
575 if (ssh->rdomain_in != NULL)
576 return ssh->rdomain_in;
577 if (!ssh_packet_connection_is_on_socket(ssh))
579 ssh->rdomain_in = get_rdomain(ssh->state->connection_in);
580 return ssh->rdomain_in;
583 /* Closes the connection and clears and frees internal data structures. */
586 ssh_packet_close_internal(struct ssh *ssh, int do_close)
588 struct session_state *state = ssh->state;
591 if (!state->initialized)
593 state->initialized = 0;
595 if (state->connection_in == state->connection_out) {
596 close(state->connection_out);
598 close(state->connection_in);
599 close(state->connection_out);
602 sshbuf_free(state->input);
603 sshbuf_free(state->output);
604 sshbuf_free(state->outgoing_packet);
605 sshbuf_free(state->incoming_packet);
606 for (mode = 0; mode < MODE_MAX; mode++) {
607 kex_free_newkeys(state->newkeys[mode]); /* current keys */
608 state->newkeys[mode] = NULL;
609 ssh_clear_newkeys(ssh, mode); /* next keys */
611 /* compression state is in shared mem, so we can only release it once */
612 if (do_close && state->compression_buffer) {
613 sshbuf_free(state->compression_buffer);
614 if (state->compression_out_started) {
615 z_streamp stream = &state->compression_out_stream;
616 debug("compress outgoing: "
617 "raw data %llu, compressed %llu, factor %.2f",
618 (unsigned long long)stream->total_in,
619 (unsigned long long)stream->total_out,
620 stream->total_in == 0 ? 0.0 :
621 (double) stream->total_out / stream->total_in);
622 if (state->compression_out_failures == 0)
625 if (state->compression_in_started) {
626 z_streamp stream = &state->compression_in_stream;
627 debug("compress incoming: "
628 "raw data %llu, compressed %llu, factor %.2f",
629 (unsigned long long)stream->total_out,
630 (unsigned long long)stream->total_in,
631 stream->total_out == 0 ? 0.0 :
632 (double) stream->total_in / stream->total_out);
633 if (state->compression_in_failures == 0)
637 cipher_free(state->send_context);
638 cipher_free(state->receive_context);
639 state->send_context = state->receive_context = NULL;
641 free(ssh->local_ipaddr);
642 ssh->local_ipaddr = NULL;
643 free(ssh->remote_ipaddr);
644 ssh->remote_ipaddr = NULL;
651 ssh_packet_close(struct ssh *ssh)
653 ssh_packet_close_internal(ssh, 1);
657 ssh_packet_clear_keys(struct ssh *ssh)
659 ssh_packet_close_internal(ssh, 0);
662 /* Sets remote side protocol flags. */
665 ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
667 ssh->state->remote_protocol_flags = protocol_flags;
670 /* Returns the remote protocol flags set earlier by the above function. */
673 ssh_packet_get_protocol_flags(struct ssh *ssh)
675 return ssh->state->remote_protocol_flags;
679 * Starts packet compression from the next packet on in both directions.
680 * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
684 ssh_packet_init_compression(struct ssh *ssh)
686 if (!ssh->state->compression_buffer &&
687 ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
688 return SSH_ERR_ALLOC_FAIL;
693 start_compression_out(struct ssh *ssh, int level)
695 if (level < 1 || level > 9)
696 return SSH_ERR_INVALID_ARGUMENT;
697 debug("Enabling compression at level %d.", level);
698 if (ssh->state->compression_out_started == 1)
699 deflateEnd(&ssh->state->compression_out_stream);
700 switch (deflateInit(&ssh->state->compression_out_stream, level)) {
702 ssh->state->compression_out_started = 1;
705 return SSH_ERR_ALLOC_FAIL;
707 return SSH_ERR_INTERNAL_ERROR;
713 start_compression_in(struct ssh *ssh)
715 if (ssh->state->compression_in_started == 1)
716 inflateEnd(&ssh->state->compression_in_stream);
717 switch (inflateInit(&ssh->state->compression_in_stream)) {
719 ssh->state->compression_in_started = 1;
722 return SSH_ERR_ALLOC_FAIL;
724 return SSH_ERR_INTERNAL_ERROR;
729 /* XXX remove need for separate compression buffer */
731 compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
736 if (ssh->state->compression_out_started != 1)
737 return SSH_ERR_INTERNAL_ERROR;
739 /* This case is not handled below. */
740 if (sshbuf_len(in) == 0)
743 /* Input is the contents of the input buffer. */
744 if ((ssh->state->compression_out_stream.next_in =
745 sshbuf_mutable_ptr(in)) == NULL)
746 return SSH_ERR_INTERNAL_ERROR;
747 ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
749 /* Loop compressing until deflate() returns with avail_out != 0. */
751 /* Set up fixed-size output buffer. */
752 ssh->state->compression_out_stream.next_out = buf;
753 ssh->state->compression_out_stream.avail_out = sizeof(buf);
755 /* Compress as much data into the buffer as possible. */
756 status = deflate(&ssh->state->compression_out_stream,
760 return SSH_ERR_ALLOC_FAIL;
762 /* Append compressed data to output_buffer. */
763 if ((r = sshbuf_put(out, buf, sizeof(buf) -
764 ssh->state->compression_out_stream.avail_out)) != 0)
769 ssh->state->compression_out_failures++;
770 return SSH_ERR_INVALID_FORMAT;
772 } while (ssh->state->compression_out_stream.avail_out == 0);
777 uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
782 if (ssh->state->compression_in_started != 1)
783 return SSH_ERR_INTERNAL_ERROR;
785 if ((ssh->state->compression_in_stream.next_in =
786 sshbuf_mutable_ptr(in)) == NULL)
787 return SSH_ERR_INTERNAL_ERROR;
788 ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
791 /* Set up fixed-size output buffer. */
792 ssh->state->compression_in_stream.next_out = buf;
793 ssh->state->compression_in_stream.avail_out = sizeof(buf);
795 status = inflate(&ssh->state->compression_in_stream,
799 if ((r = sshbuf_put(out, buf, sizeof(buf) -
800 ssh->state->compression_in_stream.avail_out)) != 0)
805 * Comments in zlib.h say that we should keep calling
806 * inflate() until we get an error. This appears to
807 * be the error that we get.
811 return SSH_ERR_INVALID_FORMAT;
813 return SSH_ERR_ALLOC_FAIL;
816 ssh->state->compression_in_failures++;
817 return SSH_ERR_INTERNAL_ERROR;
824 ssh_clear_newkeys(struct ssh *ssh, int mode)
826 if (ssh->kex && ssh->kex->newkeys[mode]) {
827 kex_free_newkeys(ssh->kex->newkeys[mode]);
828 ssh->kex->newkeys[mode] = NULL;
833 ssh_set_newkeys(struct ssh *ssh, int mode)
835 struct session_state *state = ssh->state;
838 struct sshcomp *comp;
839 struct sshcipher_ctx **ccp;
840 struct packet_state *ps;
841 u_int64_t *max_blocks;
844 const char *dir = mode == MODE_OUT ? "out" : "in";
846 debug2("set_newkeys: mode %d", mode);
848 if (mode == MODE_OUT) {
849 ccp = &state->send_context;
850 crypt_type = CIPHER_ENCRYPT;
852 max_blocks = &state->max_blocks_out;
854 ccp = &state->receive_context;
855 crypt_type = CIPHER_DECRYPT;
857 max_blocks = &state->max_blocks_in;
859 if (state->newkeys[mode] != NULL) {
860 debug("%s: rekeying %s, input %llu bytes %llu blocks, "
861 "output %llu bytes %llu blocks", __func__, dir,
862 (unsigned long long)state->p_read.bytes,
863 (unsigned long long)state->p_read.blocks,
864 (unsigned long long)state->p_send.bytes,
865 (unsigned long long)state->p_send.blocks);
866 kex_free_newkeys(state->newkeys[mode]);
867 state->newkeys[mode] = NULL;
869 /* note that both bytes and the seqnr are not reset */
870 ps->packets = ps->blocks = 0;
871 /* move newkeys from kex to state */
872 if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
873 return SSH_ERR_INTERNAL_ERROR;
874 ssh->kex->newkeys[mode] = NULL;
875 enc = &state->newkeys[mode]->enc;
876 mac = &state->newkeys[mode]->mac;
877 comp = &state->newkeys[mode]->comp;
878 if (cipher_authlen(enc->cipher) == 0) {
879 if ((r = mac_init(mac)) != 0)
883 DBG(debug("%s: cipher_init_context: %s", __func__, dir));
886 if ((r = cipher_init(ccp, enc->cipher, enc->key, enc->key_len,
887 enc->iv, enc->iv_len, crypt_type)) != 0)
889 if (!state->cipher_warning_done &&
890 (wmsg = cipher_warning_message(*ccp)) != NULL) {
891 error("Warning: %s", wmsg);
892 state->cipher_warning_done = 1;
894 /* Deleting the keys does not gain extra security */
895 /* explicit_bzero(enc->iv, enc->block_size);
896 explicit_bzero(enc->key, enc->key_len);
897 explicit_bzero(mac->key, mac->key_len); */
898 if ((comp->type == COMP_ZLIB ||
899 (comp->type == COMP_DELAYED &&
900 state->after_authentication)) && comp->enabled == 0) {
901 if ((r = ssh_packet_init_compression(ssh)) < 0)
903 if (mode == MODE_OUT) {
904 if ((r = start_compression_out(ssh, 6)) != 0)
907 if ((r = start_compression_in(ssh)) != 0)
913 * The 2^(blocksize*2) limit is too expensive for 3DES,
914 * so enforce a 1GB limit for small blocksizes.
915 * See RFC4344 section 3.2.
917 if (enc->block_size >= 16)
918 *max_blocks = (u_int64_t)1 << (enc->block_size*2);
920 *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
921 if (state->rekey_limit)
922 *max_blocks = MINIMUM(*max_blocks,
923 state->rekey_limit / enc->block_size);
924 debug("rekey %s after %llu blocks", dir,
925 (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_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) maximum 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) {
1342 r = SSH_ERR_SYSTEM_ERROR;
1345 if (state->packet_timeout_ms == -1)
1347 ms_subtract_diff(&start, &ms_remain);
1348 if (ms_remain <= 0) {
1354 r = SSH_ERR_CONN_TIMEOUT;
1357 /* Read data from the socket. */
1358 len = read(state->connection_in, buf, sizeof(buf));
1360 r = SSH_ERR_CONN_CLOSED;
1364 r = SSH_ERR_SYSTEM_ERROR;
1368 /* Append it to the buffer. */
1369 if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1378 ssh_packet_read(struct ssh *ssh)
1383 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1384 fatal("%s: %s", __func__, ssh_err(r));
1389 * Waits until a packet has been received, verifies that its type matches
1390 * that given, and gives a fatal error and exits if there is a mismatch.
1394 ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1399 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1401 if (type != expected_type) {
1402 if ((r = sshpkt_disconnect(ssh,
1403 "Protocol error: expected packet type %d, got %d",
1404 expected_type, type)) != 0)
1406 return SSH_ERR_PROTOCOL_ERROR;
1412 ssh_packet_read_poll2_mux(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1414 struct session_state *state = ssh->state;
1420 return SSH_ERR_INTERNAL_ERROR;
1421 *typep = SSH_MSG_NONE;
1422 cp = sshbuf_ptr(state->input);
1423 if (state->packlen == 0) {
1424 if (sshbuf_len(state->input) < 4 + 1)
1425 return 0; /* packet is incomplete */
1426 state->packlen = PEEK_U32(cp);
1427 if (state->packlen < 4 + 1 ||
1428 state->packlen > PACKET_MAX_SIZE)
1429 return SSH_ERR_MESSAGE_INCOMPLETE;
1431 need = state->packlen + 4;
1432 if (sshbuf_len(state->input) < need)
1433 return 0; /* packet is incomplete */
1434 sshbuf_reset(state->incoming_packet);
1435 if ((r = sshbuf_put(state->incoming_packet, cp + 4,
1436 state->packlen)) != 0 ||
1437 (r = sshbuf_consume(state->input, need)) != 0 ||
1438 (r = sshbuf_get_u8(state->incoming_packet, NULL)) != 0 ||
1439 (r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1441 if (ssh_packet_log_type(*typep))
1442 debug3("%s: type %u", __func__, *typep);
1443 /* sshbuf_dump(state->incoming_packet, stderr); */
1444 /* reset for next packet */
1450 ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1452 struct session_state *state = ssh->state;
1455 u_int maclen, aadlen = 0, authlen = 0, block_size;
1456 struct sshenc *enc = NULL;
1457 struct sshmac *mac = NULL;
1458 struct sshcomp *comp = NULL;
1462 return ssh_packet_read_poll2_mux(ssh, typep, seqnr_p);
1464 *typep = SSH_MSG_NONE;
1466 if (state->packet_discard)
1469 if (state->newkeys[MODE_IN] != NULL) {
1470 enc = &state->newkeys[MODE_IN]->enc;
1471 mac = &state->newkeys[MODE_IN]->mac;
1472 comp = &state->newkeys[MODE_IN]->comp;
1473 /* disable mac for authenticated encryption */
1474 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1477 maclen = mac && mac->enabled ? mac->mac_len : 0;
1478 block_size = enc ? enc->block_size : 8;
1479 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1481 if (aadlen && state->packlen == 0) {
1482 if (cipher_get_length(state->receive_context,
1483 &state->packlen, state->p_read.seqnr,
1484 sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1486 if (state->packlen < 1 + 4 ||
1487 state->packlen > PACKET_MAX_SIZE) {
1489 sshbuf_dump(state->input, stderr);
1491 logit("Bad packet length %u.", state->packlen);
1492 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1494 return SSH_ERR_CONN_CORRUPT;
1496 sshbuf_reset(state->incoming_packet);
1497 } else if (state->packlen == 0) {
1499 * check if input size is less than the cipher block size,
1500 * decrypt first block and extract length of incoming packet
1502 if (sshbuf_len(state->input) < block_size)
1504 sshbuf_reset(state->incoming_packet);
1505 if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1508 if ((r = cipher_crypt(state->receive_context,
1509 state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1510 block_size, 0, 0)) != 0)
1512 state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1513 if (state->packlen < 1 + 4 ||
1514 state->packlen > PACKET_MAX_SIZE) {
1516 fprintf(stderr, "input: \n");
1517 sshbuf_dump(state->input, stderr);
1518 fprintf(stderr, "incoming_packet: \n");
1519 sshbuf_dump(state->incoming_packet, stderr);
1521 logit("Bad packet length %u.", state->packlen);
1522 return ssh_packet_start_discard(ssh, enc, mac, 0,
1525 if ((r = sshbuf_consume(state->input, block_size)) != 0)
1528 DBG(debug("input: packet len %u", state->packlen+4));
1531 /* only the payload is encrypted */
1532 need = state->packlen;
1535 * the payload size and the payload are encrypted, but we
1536 * have a partial packet of block_size bytes
1538 need = 4 + state->packlen - block_size;
1540 DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1541 " aadlen %d", block_size, need, maclen, authlen, aadlen));
1542 if (need % block_size != 0) {
1543 logit("padding error: need %d block %d mod %d",
1544 need, block_size, need % block_size);
1545 return ssh_packet_start_discard(ssh, enc, mac, 0,
1546 PACKET_MAX_SIZE - block_size);
1549 * check if the entire packet has been received and
1550 * decrypt into incoming_packet:
1551 * 'aadlen' bytes are unencrypted, but authenticated.
1552 * 'need' bytes are encrypted, followed by either
1553 * 'authlen' bytes of authentication tag or
1554 * 'maclen' bytes of message authentication code.
1556 if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1557 return 0; /* packet is incomplete */
1559 fprintf(stderr, "read_poll enc/full: ");
1560 sshbuf_dump(state->input, stderr);
1562 /* EtM: check mac over encrypted input */
1563 if (mac && mac->enabled && mac->etm) {
1564 if ((r = mac_check(mac, state->p_read.seqnr,
1565 sshbuf_ptr(state->input), aadlen + need,
1566 sshbuf_ptr(state->input) + aadlen + need + authlen,
1568 if (r == SSH_ERR_MAC_INVALID)
1569 logit("Corrupted MAC on input.");
1573 if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1576 if ((r = cipher_crypt(state->receive_context, state->p_read.seqnr, cp,
1577 sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1579 if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1581 if (mac && mac->enabled) {
1582 /* Not EtM: check MAC over cleartext */
1583 if (!mac->etm && (r = mac_check(mac, state->p_read.seqnr,
1584 sshbuf_ptr(state->incoming_packet),
1585 sshbuf_len(state->incoming_packet),
1586 sshbuf_ptr(state->input), maclen)) != 0) {
1587 if (r != SSH_ERR_MAC_INVALID)
1589 logit("Corrupted MAC on input.");
1590 if (need + block_size > PACKET_MAX_SIZE)
1591 return SSH_ERR_INTERNAL_ERROR;
1592 return ssh_packet_start_discard(ssh, enc, mac,
1593 sshbuf_len(state->incoming_packet),
1594 PACKET_MAX_SIZE - need - block_size);
1596 /* Remove MAC from input buffer */
1597 DBG(debug("MAC #%d ok", state->p_read.seqnr));
1598 if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1601 if (seqnr_p != NULL)
1602 *seqnr_p = state->p_read.seqnr;
1603 if (++state->p_read.seqnr == 0)
1604 logit("incoming seqnr wraps around");
1605 if (++state->p_read.packets == 0)
1606 if (!(ssh->compat & SSH_BUG_NOREKEY))
1607 return SSH_ERR_NEED_REKEY;
1608 state->p_read.blocks += (state->packlen + 4) / block_size;
1609 state->p_read.bytes += state->packlen + 4;
1612 padlen = sshbuf_ptr(state->incoming_packet)[4];
1613 DBG(debug("input: padlen %d", padlen));
1615 if ((r = sshpkt_disconnect(ssh,
1616 "Corrupted padlen %d on input.", padlen)) != 0 ||
1617 (r = ssh_packet_write_wait(ssh)) != 0)
1619 return SSH_ERR_CONN_CORRUPT;
1622 /* skip packet size + padlen, discard padding */
1623 if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1624 ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1627 DBG(debug("input: len before de-compress %zd",
1628 sshbuf_len(state->incoming_packet)));
1629 if (comp && comp->enabled) {
1630 sshbuf_reset(state->compression_buffer);
1631 if ((r = uncompress_buffer(ssh, state->incoming_packet,
1632 state->compression_buffer)) != 0)
1634 sshbuf_reset(state->incoming_packet);
1635 if ((r = sshbuf_putb(state->incoming_packet,
1636 state->compression_buffer)) != 0)
1638 DBG(debug("input: len after de-compress %zd",
1639 sshbuf_len(state->incoming_packet)));
1642 * get packet type, implies consume.
1643 * return length of payload (without type field)
1645 if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1647 if (ssh_packet_log_type(*typep))
1648 debug3("receive packet: type %u", *typep);
1649 if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1650 if ((r = sshpkt_disconnect(ssh,
1651 "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1652 (r = ssh_packet_write_wait(ssh)) != 0)
1654 return SSH_ERR_PROTOCOL_ERROR;
1656 if (state->hook_in != NULL &&
1657 (r = state->hook_in(ssh, state->incoming_packet, typep,
1658 state->hook_in_ctx)) != 0)
1660 if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1661 r = ssh_packet_enable_delayed_compress(ssh);
1665 fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1666 sshbuf_dump(state->incoming_packet, stderr);
1668 /* reset for next packet */
1671 /* do we need to rekey? */
1672 if (ssh_packet_need_rekeying(ssh, 0)) {
1673 debug3("%s: rekex triggered", __func__);
1674 if ((r = kex_start_rekex(ssh)) != 0)
1682 ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1684 struct session_state *state = ssh->state;
1685 u_int reason, seqnr;
1691 r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1695 state->keep_alive_timeouts = 0;
1696 DBG(debug("received packet type %d", *typep));
1699 case SSH2_MSG_IGNORE:
1700 debug3("Received SSH2_MSG_IGNORE");
1702 case SSH2_MSG_DEBUG:
1703 if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1704 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1705 (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1709 debug("Remote: %.900s", msg);
1712 case SSH2_MSG_DISCONNECT:
1713 if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1714 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1716 /* Ignore normal client exit notifications */
1717 do_log2(ssh->state->server_side &&
1718 reason == SSH2_DISCONNECT_BY_APPLICATION ?
1719 SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1720 "Received disconnect from %s port %d:"
1721 "%u: %.400s", ssh_remote_ipaddr(ssh),
1722 ssh_remote_port(ssh), reason, msg);
1724 return SSH_ERR_DISCONNECTED;
1725 case SSH2_MSG_UNIMPLEMENTED:
1726 if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1728 debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1738 * Buffers the given amount of input characters. This is intended to be used
1739 * together with packet_read_poll.
1743 ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1745 struct session_state *state = ssh->state;
1748 if (state->packet_discard) {
1749 state->keep_alive_timeouts = 0; /* ?? */
1750 if (len >= state->packet_discard) {
1751 if ((r = ssh_packet_stop_discard(ssh)) != 0)
1754 state->packet_discard -= len;
1757 if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1764 ssh_packet_remaining(struct ssh *ssh)
1766 return sshbuf_len(ssh->state->incoming_packet);
1770 * Sends a diagnostic message from the server to the client. This message
1771 * can be sent at any time (but not while constructing another message). The
1772 * message is printed immediately, but only if the client is being executed
1773 * in verbose mode. These messages are primarily intended to ease debugging
1774 * authentication problems. The length of the formatted message must not
1775 * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1778 ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1784 if ((ssh->compat & SSH_BUG_DEBUG))
1787 va_start(args, fmt);
1788 vsnprintf(buf, sizeof(buf), fmt, args);
1791 debug3("sending debug message: %s", buf);
1793 if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1794 (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1795 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1796 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1797 (r = sshpkt_send(ssh)) != 0 ||
1798 (r = ssh_packet_write_wait(ssh)) != 0)
1799 fatal("%s: %s", __func__, ssh_err(r));
1803 sshpkt_fmt_connection_id(struct ssh *ssh, char *s, size_t l)
1805 snprintf(s, l, "%.200s%s%s port %d",
1806 ssh->log_preamble ? ssh->log_preamble : "",
1807 ssh->log_preamble ? " " : "",
1808 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1812 * Pretty-print connection-terminating errors and exit.
1815 sshpkt_vfatal(struct ssh *ssh, int r, const char *fmt, va_list ap)
1817 char *tag = NULL, remote_id[512];
1819 sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1822 case SSH_ERR_CONN_CLOSED:
1823 ssh_packet_clear_keys(ssh);
1824 logdie("Connection closed by %s", remote_id);
1825 case SSH_ERR_CONN_TIMEOUT:
1826 ssh_packet_clear_keys(ssh);
1827 logdie("Connection %s %s timed out",
1828 ssh->state->server_side ? "from" : "to", remote_id);
1829 case SSH_ERR_DISCONNECTED:
1830 ssh_packet_clear_keys(ssh);
1831 logdie("Disconnected from %s", remote_id);
1832 case SSH_ERR_SYSTEM_ERROR:
1833 if (errno == ECONNRESET) {
1834 ssh_packet_clear_keys(ssh);
1835 logdie("Connection reset by %s", remote_id);
1838 case SSH_ERR_NO_CIPHER_ALG_MATCH:
1839 case SSH_ERR_NO_MAC_ALG_MATCH:
1840 case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1841 case SSH_ERR_NO_KEX_ALG_MATCH:
1842 case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1843 if (ssh && ssh->kex && ssh->kex->failed_choice) {
1844 ssh_packet_clear_keys(ssh);
1845 logdie("Unable to negotiate with %s: %s. "
1846 "Their offer: %s", remote_id, ssh_err(r),
1847 ssh->kex->failed_choice);
1851 if (vasprintf(&tag, fmt, ap) == -1) {
1852 ssh_packet_clear_keys(ssh);
1853 logdie("%s: could not allocate failure message",
1856 ssh_packet_clear_keys(ssh);
1857 logdie("%s%sConnection %s %s: %s",
1858 tag != NULL ? tag : "", tag != NULL ? ": " : "",
1859 ssh->state->server_side ? "from" : "to",
1860 remote_id, ssh_err(r));
1865 sshpkt_fatal(struct ssh *ssh, int r, const char *fmt, ...)
1870 sshpkt_vfatal(ssh, r, fmt, ap);
1873 logdie("%s: should have exited", __func__);
1877 * Logs the error plus constructs and sends a disconnect packet, closes the
1878 * connection, and exits. This function never returns. The error message
1879 * should not contain a newline. The length of the formatted message must
1880 * not exceed 1024 bytes.
1883 ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1885 char buf[1024], remote_id[512];
1887 static int disconnecting = 0;
1890 if (disconnecting) /* Guard against recursive invocations. */
1891 fatal("packet_disconnect called recursively.");
1895 * Format the message. Note that the caller must make sure the
1896 * message is of limited size.
1898 sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1899 va_start(args, fmt);
1900 vsnprintf(buf, sizeof(buf), fmt, args);
1903 /* Display the error locally */
1904 logit("Disconnecting %s: %.100s", remote_id, buf);
1907 * Send the disconnect message to the other side, and wait
1908 * for it to get sent.
1910 if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1911 sshpkt_fatal(ssh, r, "%s", __func__);
1913 if ((r = ssh_packet_write_wait(ssh)) != 0)
1914 sshpkt_fatal(ssh, r, "%s", __func__);
1916 /* Close the connection. */
1917 ssh_packet_close(ssh);
1922 * Checks if there is any buffered output, and tries to write some of
1926 ssh_packet_write_poll(struct ssh *ssh)
1928 struct session_state *state = ssh->state;
1929 int len = sshbuf_len(state->output);
1933 len = write(state->connection_out,
1934 sshbuf_ptr(state->output), len);
1936 if (errno == EINTR || errno == EAGAIN ||
1937 errno == EWOULDBLOCK)
1939 return SSH_ERR_SYSTEM_ERROR;
1942 return SSH_ERR_CONN_CLOSED;
1943 if ((r = sshbuf_consume(state->output, len)) != 0)
1950 * Calls packet_write_poll repeatedly until all pending output data has been
1954 ssh_packet_write_wait(struct ssh *ssh)
1957 int ret, r, ms_remain = 0;
1958 struct timeval start, timeout, *timeoutp = NULL;
1959 struct session_state *state = ssh->state;
1961 setp = calloc(howmany(state->connection_out + 1,
1962 NFDBITS), sizeof(fd_mask));
1964 return SSH_ERR_ALLOC_FAIL;
1965 if ((r = ssh_packet_write_poll(ssh)) != 0) {
1969 while (ssh_packet_have_data_to_write(ssh)) {
1970 memset(setp, 0, howmany(state->connection_out + 1,
1971 NFDBITS) * sizeof(fd_mask));
1972 FD_SET(state->connection_out, setp);
1974 if (state->packet_timeout_ms > 0) {
1975 ms_remain = state->packet_timeout_ms;
1976 timeoutp = &timeout;
1979 if (state->packet_timeout_ms != -1) {
1980 ms_to_timeval(&timeout, ms_remain);
1981 monotime_tv(&start);
1983 if ((ret = select(state->connection_out + 1,
1984 NULL, setp, NULL, timeoutp)) >= 0)
1986 if (errno != EAGAIN && errno != EINTR &&
1987 errno != EWOULDBLOCK)
1989 if (state->packet_timeout_ms == -1)
1991 ms_subtract_diff(&start, &ms_remain);
1992 if (ms_remain <= 0) {
1999 return SSH_ERR_CONN_TIMEOUT;
2001 if ((r = ssh_packet_write_poll(ssh)) != 0) {
2010 /* Returns true if there is buffered data to write to the connection. */
2013 ssh_packet_have_data_to_write(struct ssh *ssh)
2015 return sshbuf_len(ssh->state->output) != 0;
2018 /* Returns true if there is not too much data to write to the connection. */
2021 ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
2023 if (ssh->state->interactive_mode)
2024 return sshbuf_len(ssh->state->output) < 16384;
2026 return sshbuf_len(ssh->state->output) < 128 * 1024;
2030 ssh_packet_set_tos(struct ssh *ssh, int tos)
2032 #ifndef IP_TOS_IS_BROKEN
2033 if (!ssh_packet_connection_is_on_socket(ssh) || tos == INT_MAX)
2035 switch (ssh_packet_connection_af(ssh)) {
2038 debug3("%s: set IP_TOS 0x%02x", __func__, tos);
2039 if (setsockopt(ssh->state->connection_in,
2040 IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2041 error("setsockopt IP_TOS %d: %.100s:",
2042 tos, strerror(errno));
2044 # endif /* IP_TOS */
2047 debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
2048 if (setsockopt(ssh->state->connection_in,
2049 IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2050 error("setsockopt IPV6_TCLASS %d: %.100s:",
2051 tos, strerror(errno));
2053 # endif /* IPV6_TCLASS */
2055 #endif /* IP_TOS_IS_BROKEN */
2058 /* Informs that the current session is interactive. Sets IP flags for that. */
2061 ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
2063 struct session_state *state = ssh->state;
2065 if (state->set_interactive_called)
2067 state->set_interactive_called = 1;
2069 /* Record that we are in interactive mode. */
2070 state->interactive_mode = interactive;
2072 /* Only set socket options if using a socket. */
2073 if (!ssh_packet_connection_is_on_socket(ssh))
2075 set_nodelay(state->connection_in);
2076 ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2080 /* Returns true if the current connection is interactive. */
2083 ssh_packet_is_interactive(struct ssh *ssh)
2085 return ssh->state->interactive_mode;
2089 ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
2091 struct session_state *state = ssh->state;
2093 if (state->set_maxsize_called) {
2094 logit("packet_set_maxsize: called twice: old %d new %d",
2095 state->max_packet_size, s);
2098 if (s < 4 * 1024 || s > 1024 * 1024) {
2099 logit("packet_set_maxsize: bad size %d", s);
2102 state->set_maxsize_called = 1;
2103 debug("packet_set_maxsize: setting to %d", s);
2104 state->max_packet_size = s;
2109 ssh_packet_inc_alive_timeouts(struct ssh *ssh)
2111 return ++ssh->state->keep_alive_timeouts;
2115 ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
2117 ssh->state->keep_alive_timeouts = ka;
2121 ssh_packet_get_maxsize(struct ssh *ssh)
2123 return ssh->state->max_packet_size;
2127 ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, u_int32_t seconds)
2129 debug3("rekey after %llu bytes, %u seconds", (unsigned long long)bytes,
2130 (unsigned int)seconds);
2131 ssh->state->rekey_limit = bytes;
2132 ssh->state->rekey_interval = seconds;
2136 ssh_packet_get_rekey_timeout(struct ssh *ssh)
2140 seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
2142 return (seconds <= 0 ? 1 : seconds);
2146 ssh_packet_set_server(struct ssh *ssh)
2148 ssh->state->server_side = 1;
2149 ssh->kex->server = 1; /* XXX unify? */
2153 ssh_packet_set_authenticated(struct ssh *ssh)
2155 ssh->state->after_authentication = 1;
2159 ssh_packet_get_input(struct ssh *ssh)
2161 return (void *)ssh->state->input;
2165 ssh_packet_get_output(struct ssh *ssh)
2167 return (void *)ssh->state->output;
2170 /* Reset after_authentication and reset compression in post-auth privsep */
2172 ssh_packet_set_postauth(struct ssh *ssh)
2176 debug("%s: called", __func__);
2177 /* This was set in net child, but is not visible in user child */
2178 ssh->state->after_authentication = 1;
2179 ssh->state->rekeying = 0;
2180 if ((r = ssh_packet_enable_delayed_compress(ssh)) != 0)
2185 /* Packet state (de-)serialization for privsep */
2187 /* turn kex into a blob for packet state serialization */
2189 kex_to_blob(struct sshbuf *m, struct kex *kex)
2193 if ((r = sshbuf_put_string(m, kex->session_id,
2194 kex->session_id_len)) != 0 ||
2195 (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2196 (r = sshbuf_put_cstring(m, kex->hostkey_alg)) != 0 ||
2197 (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2198 (r = sshbuf_put_u32(m, kex->hostkey_nid)) != 0 ||
2199 (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2200 (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2201 (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2202 (r = sshbuf_put_stringb(m, kex->client_version)) != 0 ||
2203 (r = sshbuf_put_stringb(m, kex->server_version)) != 0 ||
2204 (r = sshbuf_put_u32(m, kex->flags)) != 0)
2209 /* turn key exchange results into a blob for packet state serialization */
2211 newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2214 struct sshcipher_ctx *cc;
2215 struct sshcomp *comp;
2218 struct newkeys *newkey;
2221 if ((newkey = ssh->state->newkeys[mode]) == NULL)
2222 return SSH_ERR_INTERNAL_ERROR;
2225 comp = &newkey->comp;
2226 cc = (mode == MODE_OUT) ? ssh->state->send_context :
2227 ssh->state->receive_context;
2228 if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2230 if ((b = sshbuf_new()) == NULL)
2231 return SSH_ERR_ALLOC_FAIL;
2232 if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2233 (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2234 (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2235 (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2236 (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2238 if (cipher_authlen(enc->cipher) == 0) {
2239 if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2240 (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2241 (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2244 if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2245 (r = sshbuf_put_cstring(b, comp->name)) != 0)
2247 r = sshbuf_put_stringb(m, b);
2253 /* serialize packet state into a blob */
2255 ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2257 struct session_state *state = ssh->state;
2260 if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2261 (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2262 (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
2263 (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
2264 (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
2265 (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2266 (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2267 (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2268 (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2269 (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2270 (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2271 (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2272 (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0 ||
2273 (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2274 (r = sshbuf_put_stringb(m, state->output)) != 0)
2280 /* restore key exchange results from blob for packet state de-serialization */
2282 newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2284 struct sshbuf *b = NULL;
2285 struct sshcomp *comp;
2288 struct newkeys *newkey = NULL;
2289 size_t keylen, ivlen, maclen;
2292 if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2293 r = SSH_ERR_ALLOC_FAIL;
2296 if ((r = sshbuf_froms(m, &b)) != 0)
2299 sshbuf_dump(b, stderr);
2303 comp = &newkey->comp;
2305 if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2306 (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2307 (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2308 (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2309 (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2311 if ((enc->cipher = cipher_by_name(enc->name)) == NULL) {
2312 r = SSH_ERR_INVALID_FORMAT;
2315 if (cipher_authlen(enc->cipher) == 0) {
2316 if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2318 if ((r = mac_setup(mac, mac->name)) != 0)
2320 if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2321 (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2323 if (maclen > mac->key_len) {
2324 r = SSH_ERR_INVALID_FORMAT;
2327 mac->key_len = maclen;
2329 if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2330 (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2332 if (sshbuf_len(b) != 0) {
2333 r = SSH_ERR_INVALID_FORMAT;
2336 enc->key_len = keylen;
2337 enc->iv_len = ivlen;
2338 ssh->kex->newkeys[mode] = newkey;
2347 /* restore kex from blob for packet state de-serialization */
2349 kex_from_blob(struct sshbuf *m, struct kex **kexp)
2354 if ((kex = kex_new()) == NULL)
2355 return SSH_ERR_ALLOC_FAIL;
2356 if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2357 (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2358 (r = sshbuf_get_cstring(m, &kex->hostkey_alg, NULL)) != 0 ||
2359 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2360 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_nid)) != 0 ||
2361 (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2362 (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2363 (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2364 (r = sshbuf_get_stringb(m, kex->client_version)) != 0 ||
2365 (r = sshbuf_get_stringb(m, kex->server_version)) != 0 ||
2366 (r = sshbuf_get_u32(m, &kex->flags)) != 0)
2372 if (r != 0 || kexp == NULL) {
2384 * Restore packet state from content of blob 'm' (de-serialization).
2385 * Note that 'm' will be partially consumed on parsing or any other errors.
2388 ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2390 struct session_state *state = ssh->state;
2391 const u_char *input, *output;
2395 if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2396 (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2397 (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
2398 (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
2399 (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
2400 (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2401 (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2402 (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2403 (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2404 (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2405 (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2406 (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2407 (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2410 * We set the time here so that in post-auth privsep slave we
2411 * count from the completion of the authentication.
2413 state->rekey_time = monotime();
2414 /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2415 if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2416 (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2419 if ((r = ssh_packet_set_postauth(ssh)) != 0)
2422 sshbuf_reset(state->input);
2423 sshbuf_reset(state->output);
2424 if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2425 (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2426 (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2427 (r = sshbuf_put(state->output, output, olen)) != 0)
2431 return SSH_ERR_INVALID_FORMAT;
2432 debug3("%s: done", __func__);
2438 /* put data to the outgoing packet */
2441 sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2443 return sshbuf_put(ssh->state->outgoing_packet, v, len);
2447 sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2449 return sshbuf_putb(ssh->state->outgoing_packet, b);
2453 sshpkt_put_u8(struct ssh *ssh, u_char val)
2455 return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2459 sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2461 return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2465 sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2467 return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2471 sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2473 return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2477 sshpkt_put_cstring(struct ssh *ssh, const void *v)
2479 return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2483 sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2485 return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2489 sshpkt_getb_froms(struct ssh *ssh, struct sshbuf **valp)
2491 return sshbuf_froms(ssh->state->incoming_packet, valp);
2495 #ifdef OPENSSL_HAS_ECC
2497 sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2499 return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2501 #endif /* OPENSSL_HAS_ECC */
2505 sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2507 return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2509 #endif /* WITH_OPENSSL */
2511 /* fetch data from the incoming packet */
2514 sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2516 return sshbuf_get(ssh->state->incoming_packet, valp, len);
2520 sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2522 return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2526 sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2528 return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2532 sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2534 return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2538 sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2540 return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2544 sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2546 return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2550 sshpkt_peek_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2552 return sshbuf_peek_string_direct(ssh->state->incoming_packet, valp, lenp);
2556 sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2558 return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2562 #ifdef OPENSSL_HAS_ECC
2564 sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2566 return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2568 #endif /* OPENSSL_HAS_ECC */
2571 sshpkt_get_bignum2(struct ssh *ssh, BIGNUM **valp)
2573 return sshbuf_get_bignum2(ssh->state->incoming_packet, valp);
2575 #endif /* WITH_OPENSSL */
2578 sshpkt_get_end(struct ssh *ssh)
2580 if (sshbuf_len(ssh->state->incoming_packet) > 0)
2581 return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2586 sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2589 *lenp = sshbuf_len(ssh->state->incoming_packet);
2590 return sshbuf_ptr(ssh->state->incoming_packet);
2593 /* start a new packet */
2596 sshpkt_start(struct ssh *ssh, u_char type)
2598 u_char buf[6]; /* u32 packet length, u8 pad len, u8 type */
2600 DBG(debug("packet_start[%d]", type));
2601 memset(buf, 0, sizeof(buf));
2602 buf[sizeof(buf) - 1] = type;
2603 sshbuf_reset(ssh->state->outgoing_packet);
2604 return sshbuf_put(ssh->state->outgoing_packet, buf, sizeof(buf));
2608 ssh_packet_send_mux(struct ssh *ssh)
2610 struct session_state *state = ssh->state;
2616 return SSH_ERR_INTERNAL_ERROR;
2617 len = sshbuf_len(state->outgoing_packet);
2619 return SSH_ERR_INTERNAL_ERROR;
2620 cp = sshbuf_mutable_ptr(state->outgoing_packet);
2622 if (ssh_packet_log_type(type))
2623 debug3("%s: type %u", __func__, type);
2624 /* drop everything, but the connection protocol */
2625 if (type >= SSH2_MSG_CONNECTION_MIN &&
2626 type <= SSH2_MSG_CONNECTION_MAX) {
2627 POKE_U32(cp, len - 4);
2628 if ((r = sshbuf_putb(state->output,
2629 state->outgoing_packet)) != 0)
2631 /* sshbuf_dump(state->output, stderr); */
2633 sshbuf_reset(state->outgoing_packet);
2638 * 9.2. Ignored Data Message
2640 * byte SSH_MSG_IGNORE
2643 * All implementations MUST understand (and ignore) this message at any
2644 * time (after receiving the protocol version). No implementation is
2645 * required to send them. This message can be used as an additional
2646 * protection measure against advanced traffic analysis techniques.
2649 sshpkt_msg_ignore(struct ssh *ssh, u_int nbytes)
2655 if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
2656 (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2658 for (i = 0; i < nbytes; i++) {
2661 if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2671 sshpkt_send(struct ssh *ssh)
2673 if (ssh->state && ssh->state->mux)
2674 return ssh_packet_send_mux(ssh);
2675 return ssh_packet_send2(ssh);
2679 sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2685 va_start(args, fmt);
2686 vsnprintf(buf, sizeof(buf), fmt, args);
2689 if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2690 (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2691 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2692 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2693 (r = sshpkt_send(ssh)) != 0)
2698 /* roundup current message to pad bytes */
2700 sshpkt_add_padding(struct ssh *ssh, u_char pad)
2702 ssh->state->extra_pad = pad;