blob: 6d3e9172db6cdfa4306d78603384b6742c66c581 [file] [log] [blame]
djm@openbsd.orgdce74ea2020-01-30 07:20:05 +00001/* $OpenBSD: packet.c,v 1.290 2020/01/30 07:20:05 djm Exp $ */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002/*
Damien Miller95def091999-11-25 00:26:21 +11003 * Author: Tatu Ylonen <ylo@cs.hut.fi>
Damien Miller95def091999-11-25 00:26:21 +11004 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * All rights reserved
Damien Miller95def091999-11-25 00:26:21 +11006 * 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.
Damien Miller33b13562000-04-04 14:38:59 +10008 *
Damien Millere4340be2000-09-16 13:29:08 +11009 * 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".
Damien Miller33b13562000-04-04 14:38:59 +100014 *
Damien Millere4340be2000-09-16 13:29:08 +110015 *
16 * SSH2 packet format added by Markus Friedl.
Ben Lindstrom44697232001-07-04 03:32:30 +000017 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
Damien Millere4340be2000-09-16 13:29:08 +110018 *
19 * Redistribution and use in source and binary forms, with or without
20 * modification, are permitted provided that the following conditions
21 * are met:
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.
27 *
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.
Damien Miller95def091999-11-25 00:26:21 +110038 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100039
40#include "includes.h"
deraadt@openbsd.org9136ec12016-09-12 01:22:38 +000041
Damien Millere3b60b52006-07-10 21:08:03 +100042#include <sys/types.h>
Damien Millera0898b82003-04-09 21:05:52 +100043#include "openbsd-compat/sys-queue.h"
Damien Miller8ec8c3e2006-07-10 20:35:38 +100044#include <sys/socket.h>
Damien Miller9aec9192006-08-05 10:57:45 +100045#ifdef HAVE_SYS_TIME_H
46# include <sys/time.h>
47#endif
Damien Miller8ec8c3e2006-07-10 20:35:38 +100048
Damien Miller8ec8c3e2006-07-10 20:35:38 +100049#include <netinet/in.h>
Damien Miller68f8e992006-03-15 11:24:12 +110050#include <netinet/ip.h>
Darren Tuckerdace2332006-09-22 19:22:17 +100051#include <arpa/inet.h>
Damien Millerd4a8b7e1999-10-27 13:42:43 +100052
Darren Tucker39972492006-07-12 22:22:46 +100053#include <errno.h>
djm@openbsd.org95767262016-03-07 19:02:43 +000054#include <netdb.h>
Darren Tucker5d196262006-07-12 22:15:16 +100055#include <stdarg.h>
Damien Millera7a73ee2006-08-05 11:37:59 +100056#include <stdio.h>
Damien Millere7a1e5c2006-08-05 11:34:19 +100057#include <stdlib.h>
Damien Millere3476ed2006-07-24 14:13:33 +100058#include <string.h>
Damien Millere6b3b612006-07-24 14:01:23 +100059#include <unistd.h>
deraadt@openbsd.org087266e2015-01-20 23:14:00 +000060#include <limits.h>
Darren Tucker6fc7e1c2019-10-28 15:53:25 +110061#ifdef HAVE_POLL_H
djm@openbsd.org0a843d92018-12-27 03:25:24 +000062#include <poll.h>
Darren Tucker6fc7e1c2019-10-28 15:53:25 +110063#endif
Damien Millerd7834352006-08-05 12:39:39 +100064#include <signal.h>
Darren Tuckerc53c2af2013-05-16 20:28:16 +100065#include <time.h>
Darren Tucker5d196262006-07-12 22:15:16 +100066
Darren Tuckerc77bc732018-07-20 13:48:51 +100067/*
68 * Explicitly include OpenSSL before zlib as some versions of OpenSSL have
69 * "free_func" in their headers, which zlib typedefs.
70 */
71#ifdef WITH_OPENSSL
72# include <openssl/bn.h>
73# include <openssl/evp.h>
74# ifdef OPENSSL_HAS_ECC
75# include <openssl/ec.h>
76# endif
77#endif
78
dtucker@openbsd.org7f8e66f2020-01-23 10:24:29 +000079#ifdef WITH_ZLIB
markus@openbsd.org091c3022015-01-19 19:52:16 +000080#include <zlib.h>
dtucker@openbsd.org7f8e66f2020-01-23 10:24:29 +000081#endif
markus@openbsd.org091c3022015-01-19 19:52:16 +000082
Damien Millerd4a8b7e1999-10-27 13:42:43 +100083#include "xmalloc.h"
Damien Miller33b13562000-04-04 14:38:59 +100084#include "compat.h"
85#include "ssh2.h"
Damien Miller874d77b2000-10-14 16:23:11 +110086#include "cipher.h"
markus@openbsd.org091c3022015-01-19 19:52:16 +000087#include "sshkey.h"
Damien Miller33b13562000-04-04 14:38:59 +100088#include "kex.h"
markus@openbsd.org128343b2015-01-13 19:31:40 +000089#include "digest.h"
Ben Lindstrom06b33aa2001-02-15 03:01:59 +000090#include "mac.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000091#include "log.h"
92#include "canohost.h"
Damien Miller4d007762002-02-05 11:52:54 +110093#include "misc.h"
Damien Miller7acefbb2014-07-18 14:11:24 +100094#include "channels.h"
Ben Lindstrom402c6cc2002-06-21 00:43:42 +000095#include "ssh.h"
markus@openbsd.org091c3022015-01-19 19:52:16 +000096#include "packet.h"
markus@openbsd.org091c3022015-01-19 19:52:16 +000097#include "ssherr.h"
98#include "sshbuf.h"
Damien Miller33b13562000-04-04 14:38:59 +100099
100#ifdef PACKET_DEBUG
101#define DBG(x) x
102#else
103#define DBG(x)
104#endif
105
Damien Miller13ae44c2009-01-28 16:38:41 +1100106#define PACKET_MAX_SIZE (256 * 1024)
107
Darren Tuckerf7288d72009-06-21 18:12:20 +1000108struct packet_state {
Damien Millera5539d22003-04-09 20:50:06 +1000109 u_int32_t seqnr;
110 u_int32_t packets;
111 u_int64_t blocks;
Damien Millerb61f3fc2008-07-11 17:36:48 +1000112 u_int64_t bytes;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000113};
Damien Miller13ae44c2009-01-28 16:38:41 +1100114
Damien Millera5539d22003-04-09 20:50:06 +1000115struct packet {
116 TAILQ_ENTRY(packet) next;
117 u_char type;
markus@openbsd.org091c3022015-01-19 19:52:16 +0000118 struct sshbuf *payload;
Damien Millera5539d22003-04-09 20:50:06 +1000119};
Darren Tuckerf7288d72009-06-21 18:12:20 +1000120
121struct session_state {
122 /*
123 * This variable contains the file descriptors used for
124 * communicating with the other side. connection_in is used for
125 * reading; connection_out for writing. These can be the same
126 * descriptor, in which case it is assumed to be a socket.
127 */
128 int connection_in;
129 int connection_out;
130
131 /* Protocol flags for the remote side. */
132 u_int remote_protocol_flags;
133
134 /* Encryption context for receiving data. Only used for decryption. */
djm@openbsd.org4706c1d2016-08-03 05:41:57 +0000135 struct sshcipher_ctx *receive_context;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000136
137 /* Encryption context for sending data. Only used for encryption. */
djm@openbsd.org4706c1d2016-08-03 05:41:57 +0000138 struct sshcipher_ctx *send_context;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000139
140 /* Buffer for raw input data from the socket. */
markus@openbsd.org091c3022015-01-19 19:52:16 +0000141 struct sshbuf *input;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000142
143 /* Buffer for raw output data going to the socket. */
markus@openbsd.org091c3022015-01-19 19:52:16 +0000144 struct sshbuf *output;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000145
146 /* Buffer for the partial outgoing packet being constructed. */
markus@openbsd.org091c3022015-01-19 19:52:16 +0000147 struct sshbuf *outgoing_packet;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000148
149 /* Buffer for the incoming packet currently being processed. */
markus@openbsd.org091c3022015-01-19 19:52:16 +0000150 struct sshbuf *incoming_packet;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000151
152 /* Scratch buffer for packet compression/decompression. */
markus@openbsd.org091c3022015-01-19 19:52:16 +0000153 struct sshbuf *compression_buffer;
154
dtucker@openbsd.org7f8e66f2020-01-23 10:24:29 +0000155#ifdef WITH_ZLIB
markus@openbsd.org091c3022015-01-19 19:52:16 +0000156 /* Incoming/outgoing compression dictionaries */
157 z_stream compression_in_stream;
158 z_stream compression_out_stream;
dtucker@openbsd.org7f8e66f2020-01-23 10:24:29 +0000159#endif
markus@openbsd.org091c3022015-01-19 19:52:16 +0000160 int compression_in_started;
161 int compression_out_started;
162 int compression_in_failures;
163 int compression_out_failures;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000164
Darren Tuckerf7288d72009-06-21 18:12:20 +1000165 /* default maximum packet size */
166 u_int max_packet_size;
167
168 /* Flag indicating whether this module has been initialized. */
169 int initialized;
170
171 /* Set to true if the connection is interactive. */
172 int interactive_mode;
173
174 /* Set to true if we are the server side. */
175 int server_side;
176
177 /* Set to true if we are authenticated. */
178 int after_authentication;
179
180 int keep_alive_timeouts;
181
182 /* The maximum time that we will wait to send or receive a packet */
183 int packet_timeout_ms;
184
185 /* Session key information for Encryption and MAC */
markus@openbsd.org091c3022015-01-19 19:52:16 +0000186 struct newkeys *newkeys[MODE_MAX];
Darren Tuckerf7288d72009-06-21 18:12:20 +1000187 struct packet_state p_read, p_send;
188
Darren Tuckerc53c2af2013-05-16 20:28:16 +1000189 /* Volume-based rekeying */
dtucker@openbsd.org921ff002016-01-29 02:54:45 +0000190 u_int64_t max_blocks_in, max_blocks_out, rekey_limit;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000191
Darren Tuckerc53c2af2013-05-16 20:28:16 +1000192 /* Time-based rekeying */
markus@openbsd.org02db4682015-02-13 18:57:00 +0000193 u_int32_t rekey_interval; /* how often in seconds */
Darren Tuckerc53c2af2013-05-16 20:28:16 +1000194 time_t rekey_time; /* time of last rekeying */
195
Darren Tuckerf7288d72009-06-21 18:12:20 +1000196 /* roundup current message to extra_pad bytes */
197 u_char extra_pad;
198
199 /* XXX discard incoming data after MAC error */
200 u_int packet_discard;
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +0000201 size_t packet_discard_mac_already;
markus@openbsd.org091c3022015-01-19 19:52:16 +0000202 struct sshmac *packet_discard_mac;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000203
204 /* Used in packet_read_poll2() */
205 u_int packlen;
206
Darren Tucker7b935c72009-06-21 18:59:36 +1000207 /* Used in packet_send2 */
208 int rekeying;
209
markus@openbsd.org8d057842016-09-30 09:19:13 +0000210 /* Used in ssh_packet_send_mux() */
211 int mux;
212
Darren Tucker7b935c72009-06-21 18:59:36 +1000213 /* Used in packet_set_interactive */
214 int set_interactive_called;
215
216 /* Used in packet_set_maxsize */
217 int set_maxsize_called;
218
markus@openbsd.org091c3022015-01-19 19:52:16 +0000219 /* One-off warning about weak ciphers */
220 int cipher_warning_done;
221
djm@openbsd.org39af7b42016-10-11 21:47:45 +0000222 /* Hook for fuzzing inbound packets */
223 ssh_packet_hook_fn *hook_in;
224 void *hook_in_ctx;
225
Darren Tuckerf7288d72009-06-21 18:12:20 +1000226 TAILQ_HEAD(, packet) outgoing;
227};
228
markus@openbsd.org091c3022015-01-19 19:52:16 +0000229struct ssh *
230ssh_alloc_session_state(void)
Darren Tuckerf7288d72009-06-21 18:12:20 +1000231{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000232 struct ssh *ssh = NULL;
233 struct session_state *state = NULL;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000234
markus@openbsd.org091c3022015-01-19 19:52:16 +0000235 if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
236 (state = calloc(1, sizeof(*state))) == NULL ||
djm@openbsd.org0a843d92018-12-27 03:25:24 +0000237 (ssh->kex = kex_new()) == NULL ||
markus@openbsd.org091c3022015-01-19 19:52:16 +0000238 (state->input = sshbuf_new()) == NULL ||
239 (state->output = sshbuf_new()) == NULL ||
240 (state->outgoing_packet = sshbuf_new()) == NULL ||
241 (state->incoming_packet = sshbuf_new()) == NULL)
242 goto fail;
243 TAILQ_INIT(&state->outgoing);
markus@openbsd.orgf582f0e2015-01-19 20:30:23 +0000244 TAILQ_INIT(&ssh->private_keys);
245 TAILQ_INIT(&ssh->public_keys);
markus@openbsd.org091c3022015-01-19 19:52:16 +0000246 state->connection_in = -1;
247 state->connection_out = -1;
248 state->max_packet_size = 32768;
249 state->packet_timeout_ms = -1;
250 state->p_send.packets = state->p_read.packets = 0;
251 state->initialized = 1;
252 /*
253 * ssh_packet_send2() needs to queue packets until
254 * we've done the initial key exchange.
255 */
256 state->rekeying = 1;
257 ssh->state = state;
258 return ssh;
259 fail:
djm@openbsd.org0a843d92018-12-27 03:25:24 +0000260 if (ssh) {
261 kex_free(ssh->kex);
262 free(ssh);
263 }
markus@openbsd.org091c3022015-01-19 19:52:16 +0000264 if (state) {
265 sshbuf_free(state->input);
266 sshbuf_free(state->output);
267 sshbuf_free(state->incoming_packet);
268 sshbuf_free(state->outgoing_packet);
269 free(state);
270 }
markus@openbsd.org091c3022015-01-19 19:52:16 +0000271 return NULL;
Darren Tuckerf7288d72009-06-21 18:12:20 +1000272}
Damien Millera5539d22003-04-09 20:50:06 +1000273
djm@openbsd.org39af7b42016-10-11 21:47:45 +0000274void
275ssh_packet_set_input_hook(struct ssh *ssh, ssh_packet_hook_fn *hook, void *ctx)
276{
277 ssh->state->hook_in = hook;
278 ssh->state->hook_in_ctx = ctx;
279}
280
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +0000281/* Returns nonzero if rekeying is in progress */
282int
283ssh_packet_is_rekeying(struct ssh *ssh)
284{
djm@openbsd.org0a843d92018-12-27 03:25:24 +0000285 return ssh->state->rekeying || ssh->kex->done == 0;
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +0000286}
287
Damien Miller5428f641999-11-25 11:54:57 +1100288/*
naddy@openbsd.org768405f2017-05-03 21:08:09 +0000289 * Sets the descriptors used for communication.
Damien Miller5428f641999-11-25 11:54:57 +1100290 */
markus@openbsd.org091c3022015-01-19 19:52:16 +0000291struct ssh *
292ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000293{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000294 struct session_state *state;
295 const struct sshcipher *none = cipher_by_name("none");
Damien Miller86687062014-07-02 15:28:02 +1000296 int r;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000297
djm@openbsd.org4509b5d2015-01-30 01:13:33 +0000298 if (none == NULL) {
299 error("%s: cannot load cipher 'none'", __func__);
300 return NULL;
301 }
markus@openbsd.org091c3022015-01-19 19:52:16 +0000302 if (ssh == NULL)
303 ssh = ssh_alloc_session_state();
djm@openbsd.org4509b5d2015-01-30 01:13:33 +0000304 if (ssh == NULL) {
dtucker@openbsd.org4b7dd222019-06-07 14:18:48 +0000305 error("%s: could not allocate state", __func__);
djm@openbsd.org4509b5d2015-01-30 01:13:33 +0000306 return NULL;
307 }
markus@openbsd.org091c3022015-01-19 19:52:16 +0000308 state = ssh->state;
309 state->connection_in = fd_in;
310 state->connection_out = fd_out;
311 if ((r = cipher_init(&state->send_context, none,
Damien Miller86687062014-07-02 15:28:02 +1000312 (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
markus@openbsd.org091c3022015-01-19 19:52:16 +0000313 (r = cipher_init(&state->receive_context, none,
djm@openbsd.org4509b5d2015-01-30 01:13:33 +0000314 (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
315 error("%s: cipher_init failed: %s", __func__, ssh_err(r));
djm@openbsd.org95767262016-03-07 19:02:43 +0000316 free(ssh); /* XXX need ssh_free_session_state? */
djm@openbsd.org4509b5d2015-01-30 01:13:33 +0000317 return NULL;
318 }
markus@openbsd.org091c3022015-01-19 19:52:16 +0000319 state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
djm@openbsd.orgd4c02952015-02-11 01:20:38 +0000320 /*
321 * Cache the IP address of the remote connection for use in error
322 * messages that might be generated after the connection has closed.
323 */
324 (void)ssh_remote_ipaddr(ssh);
markus@openbsd.org091c3022015-01-19 19:52:16 +0000325 return ssh;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000326}
327
Darren Tucker3fc464e2008-06-13 06:42:45 +1000328void
markus@openbsd.org091c3022015-01-19 19:52:16 +0000329ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
Darren Tucker3fc464e2008-06-13 06:42:45 +1000330{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000331 struct session_state *state = ssh->state;
332
Damien Miller8ed4de82011-12-19 10:52:50 +1100333 if (timeout <= 0 || count <= 0) {
markus@openbsd.org091c3022015-01-19 19:52:16 +0000334 state->packet_timeout_ms = -1;
Darren Tucker3fc464e2008-06-13 06:42:45 +1000335 return;
336 }
337 if ((INT_MAX / 1000) / count < timeout)
markus@openbsd.org091c3022015-01-19 19:52:16 +0000338 state->packet_timeout_ms = INT_MAX;
Darren Tucker3fc464e2008-06-13 06:42:45 +1000339 else
markus@openbsd.org091c3022015-01-19 19:52:16 +0000340 state->packet_timeout_ms = timeout * count * 1000;
Darren Tucker3fc464e2008-06-13 06:42:45 +1000341}
342
markus@openbsd.org8d057842016-09-30 09:19:13 +0000343void
344ssh_packet_set_mux(struct ssh *ssh)
345{
346 ssh->state->mux = 1;
347 ssh->state->rekeying = 0;
348}
349
350int
351ssh_packet_get_mux(struct ssh *ssh)
352{
353 return ssh->state->mux;
354}
355
markus@openbsd.org091c3022015-01-19 19:52:16 +0000356int
djm@openbsd.org07edd7e2017-02-03 23:03:33 +0000357ssh_packet_set_log_preamble(struct ssh *ssh, const char *fmt, ...)
358{
359 va_list args;
360 int r;
361
362 free(ssh->log_preamble);
363 if (fmt == NULL)
364 ssh->log_preamble = NULL;
365 else {
366 va_start(args, fmt);
367 r = vasprintf(&ssh->log_preamble, fmt, args);
368 va_end(args);
369 if (r < 0 || ssh->log_preamble == NULL)
370 return SSH_ERR_ALLOC_FAIL;
371 }
372 return 0;
373}
374
375int
markus@openbsd.org091c3022015-01-19 19:52:16 +0000376ssh_packet_stop_discard(struct ssh *ssh)
Damien Miller13ae44c2009-01-28 16:38:41 +1100377{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000378 struct session_state *state = ssh->state;
379 int r;
380
381 if (state->packet_discard_mac) {
Damien Miller13ae44c2009-01-28 16:38:41 +1100382 char buf[1024];
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +0000383 size_t dlen = PACKET_MAX_SIZE;
markus@openbsd.org091c3022015-01-19 19:52:16 +0000384
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +0000385 if (dlen > state->packet_discard_mac_already)
386 dlen -= state->packet_discard_mac_already;
Damien Miller13ae44c2009-01-28 16:38:41 +1100387 memset(buf, 'a', sizeof(buf));
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +0000388 while (sshbuf_len(state->incoming_packet) < dlen)
markus@openbsd.org091c3022015-01-19 19:52:16 +0000389 if ((r = sshbuf_put(state->incoming_packet, buf,
390 sizeof(buf))) != 0)
391 return r;
392 (void) mac_compute(state->packet_discard_mac,
393 state->p_read.seqnr,
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +0000394 sshbuf_ptr(state->incoming_packet), dlen,
markus@openbsd.org091c3022015-01-19 19:52:16 +0000395 NULL, 0);
Damien Miller13ae44c2009-01-28 16:38:41 +1100396 }
djm@openbsd.orga4b9e0f2015-12-11 03:24:25 +0000397 logit("Finished discarding for %.200s port %d",
398 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
markus@openbsd.org091c3022015-01-19 19:52:16 +0000399 return SSH_ERR_MAC_INVALID;
Damien Miller13ae44c2009-01-28 16:38:41 +1100400}
401
markus@openbsd.org091c3022015-01-19 19:52:16 +0000402static int
403ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +0000404 struct sshmac *mac, size_t mac_already, u_int discard)
Damien Miller13ae44c2009-01-28 16:38:41 +1100405{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000406 struct session_state *state = ssh->state;
407 int r;
408
409 if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
410 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
411 return r;
412 return SSH_ERR_MAC_INVALID;
413 }
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +0000414 /*
415 * Record number of bytes over which the mac has already
416 * been computed in order to minimize timing attacks.
417 */
418 if (mac && mac->enabled) {
markus@openbsd.org091c3022015-01-19 19:52:16 +0000419 state->packet_discard_mac = mac;
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +0000420 state->packet_discard_mac_already = mac_already;
421 }
422 if (sshbuf_len(state->input) >= discard)
423 return ssh_packet_stop_discard(ssh);
markus@openbsd.org091c3022015-01-19 19:52:16 +0000424 state->packet_discard = discard - sshbuf_len(state->input);
425 return 0;
Damien Miller13ae44c2009-01-28 16:38:41 +1100426}
427
Damien Miller34132e52000-01-14 15:45:46 +1100428/* Returns 1 if remote host is connected via socket, 0 if not. */
429
430int
markus@openbsd.org091c3022015-01-19 19:52:16 +0000431ssh_packet_connection_is_on_socket(struct ssh *ssh)
Damien Miller34132e52000-01-14 15:45:46 +1100432{
djm@openbsd.org854ae202018-06-01 04:05:29 +0000433 struct session_state *state;
Damien Miller34132e52000-01-14 15:45:46 +1100434 struct sockaddr_storage from, to;
435 socklen_t fromlen, tolen;
436
djm@openbsd.org854ae202018-06-01 04:05:29 +0000437 if (ssh == NULL || ssh->state == NULL)
djm@openbsd.org95767262016-03-07 19:02:43 +0000438 return 0;
439
djm@openbsd.org854ae202018-06-01 04:05:29 +0000440 state = ssh->state;
441 if (state->connection_in == -1 || state->connection_out == -1)
442 return 0;
Damien Miller34132e52000-01-14 15:45:46 +1100443 /* filedescriptors in and out are the same, so it's a socket */
markus@openbsd.org091c3022015-01-19 19:52:16 +0000444 if (state->connection_in == state->connection_out)
Damien Miller34132e52000-01-14 15:45:46 +1100445 return 1;
446 fromlen = sizeof(from);
447 memset(&from, 0, sizeof(from));
markus@openbsd.org091c3022015-01-19 19:52:16 +0000448 if (getpeername(state->connection_in, (struct sockaddr *)&from,
deraadt@openbsd.org4d28fa72019-06-28 13:35:04 +0000449 &fromlen) == -1)
Damien Miller34132e52000-01-14 15:45:46 +1100450 return 0;
451 tolen = sizeof(to);
452 memset(&to, 0, sizeof(to));
markus@openbsd.org091c3022015-01-19 19:52:16 +0000453 if (getpeername(state->connection_out, (struct sockaddr *)&to,
deraadt@openbsd.org4d28fa72019-06-28 13:35:04 +0000454 &tolen) == -1)
Damien Miller34132e52000-01-14 15:45:46 +1100455 return 0;
456 if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
457 return 0;
458 if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
459 return 0;
460 return 1;
461}
462
Ben Lindstromf6027d32002-03-22 01:42:04 +0000463void
markus@openbsd.org091c3022015-01-19 19:52:16 +0000464ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
Ben Lindstromf6027d32002-03-22 01:42:04 +0000465{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000466 if (ibytes)
467 *ibytes = ssh->state->p_read.bytes;
468 if (obytes)
469 *obytes = ssh->state->p_send.bytes;
Ben Lindstromf6027d32002-03-22 01:42:04 +0000470}
471
472int
markus@openbsd.org091c3022015-01-19 19:52:16 +0000473ssh_packet_connection_af(struct ssh *ssh)
Damien Miller34132e52000-01-14 15:45:46 +1100474{
475 struct sockaddr_storage to;
Damien Miller6fe375d2000-01-23 09:38:00 +1100476 socklen_t tolen = sizeof(to);
Damien Miller34132e52000-01-14 15:45:46 +1100477
478 memset(&to, 0, sizeof(to));
markus@openbsd.org091c3022015-01-19 19:52:16 +0000479 if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
deraadt@openbsd.org4d28fa72019-06-28 13:35:04 +0000480 &tolen) == -1)
Damien Miller34132e52000-01-14 15:45:46 +1100481 return 0;
Damien Milleraa100c52002-04-26 16:54:34 +1000482#ifdef IPV4_IN_IPV6
Damien Millera8e06ce2003-11-21 23:48:55 +1100483 if (to.ss_family == AF_INET6 &&
Damien Milleraa100c52002-04-26 16:54:34 +1000484 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr))
Damien Millerd2ac5d72011-05-15 08:43:13 +1000485 return AF_INET;
Damien Milleraa100c52002-04-26 16:54:34 +1000486#endif
Damien Millerd2ac5d72011-05-15 08:43:13 +1000487 return to.ss_family;
Damien Miller34132e52000-01-14 15:45:46 +1100488}
489
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000490/* Sets the connection into non-blocking mode. */
491
492void
markus@openbsd.org091c3022015-01-19 19:52:16 +0000493ssh_packet_set_nonblocking(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000494{
Damien Miller95def091999-11-25 00:26:21 +1100495 /* Set the socket into non-blocking mode. */
markus@openbsd.org091c3022015-01-19 19:52:16 +0000496 set_nonblock(ssh->state->connection_in);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000497
markus@openbsd.org091c3022015-01-19 19:52:16 +0000498 if (ssh->state->connection_out != ssh->state->connection_in)
499 set_nonblock(ssh->state->connection_out);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000500}
501
502/* Returns the socket used for reading. */
503
504int
markus@openbsd.org091c3022015-01-19 19:52:16 +0000505ssh_packet_get_connection_in(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000506{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000507 return ssh->state->connection_in;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000508}
509
510/* Returns the descriptor used for writing. */
511
512int
markus@openbsd.org091c3022015-01-19 19:52:16 +0000513ssh_packet_get_connection_out(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000514{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000515 return ssh->state->connection_out;
516}
517
518/*
519 * Returns the IP-address of the remote host as a string. The returned
520 * string must not be freed.
521 */
522
523const char *
524ssh_remote_ipaddr(struct ssh *ssh)
525{
djm@openbsd.org854ae202018-06-01 04:05:29 +0000526 int sock;
djm@openbsd.orga4b9e0f2015-12-11 03:24:25 +0000527
markus@openbsd.org091c3022015-01-19 19:52:16 +0000528 /* Check whether we have cached the ipaddr. */
djm@openbsd.orga4b9e0f2015-12-11 03:24:25 +0000529 if (ssh->remote_ipaddr == NULL) {
530 if (ssh_packet_connection_is_on_socket(ssh)) {
djm@openbsd.org854ae202018-06-01 04:05:29 +0000531 sock = ssh->state->connection_in;
djm@openbsd.orga4b9e0f2015-12-11 03:24:25 +0000532 ssh->remote_ipaddr = get_peer_ipaddr(sock);
djm@openbsd.org95767262016-03-07 19:02:43 +0000533 ssh->remote_port = get_peer_port(sock);
534 ssh->local_ipaddr = get_local_ipaddr(sock);
535 ssh->local_port = get_local_port(sock);
djm@openbsd.orga4b9e0f2015-12-11 03:24:25 +0000536 } else {
tobhe@openbsd.orgf65cf112019-12-16 13:58:53 +0000537 ssh->remote_ipaddr = xstrdup("UNKNOWN");
djm@openbsd.org95767262016-03-07 19:02:43 +0000538 ssh->remote_port = 65535;
tobhe@openbsd.orgf65cf112019-12-16 13:58:53 +0000539 ssh->local_ipaddr = xstrdup("UNKNOWN");
djm@openbsd.org95767262016-03-07 19:02:43 +0000540 ssh->local_port = 65535;
djm@openbsd.orga4b9e0f2015-12-11 03:24:25 +0000541 }
542 }
markus@openbsd.org091c3022015-01-19 19:52:16 +0000543 return ssh->remote_ipaddr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000544}
545
djm@openbsd.orga4b9e0f2015-12-11 03:24:25 +0000546/* Returns the port number of the remote host. */
547
548int
549ssh_remote_port(struct ssh *ssh)
550{
551 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
552 return ssh->remote_port;
553}
554
djm@openbsd.org95767262016-03-07 19:02:43 +0000555/*
556 * Returns the IP-address of the local host as a string. The returned
557 * string must not be freed.
558 */
559
560const char *
561ssh_local_ipaddr(struct ssh *ssh)
562{
563 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
564 return ssh->local_ipaddr;
565}
566
567/* Returns the port number of the local host. */
568
569int
570ssh_local_port(struct ssh *ssh)
571{
572 (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
573 return ssh->local_port;
574}
575
djm@openbsd.org35eb33f2017-10-25 00:17:08 +0000576/* Returns the routing domain of the input socket, or NULL if unavailable */
577const char *
578ssh_packet_rdomain_in(struct ssh *ssh)
579{
580 if (ssh->rdomain_in != NULL)
581 return ssh->rdomain_in;
582 if (!ssh_packet_connection_is_on_socket(ssh))
583 return NULL;
584 ssh->rdomain_in = get_rdomain(ssh->state->connection_in);
585 return ssh->rdomain_in;
586}
587
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000588/* Closes the connection and clears and frees internal data structures. */
589
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000590static void
591ssh_packet_close_internal(struct ssh *ssh, int do_close)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000592{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000593 struct session_state *state = ssh->state;
markus@openbsd.org091c3022015-01-19 19:52:16 +0000594 u_int mode;
595
596 if (!state->initialized)
Damien Miller95def091999-11-25 00:26:21 +1100597 return;
markus@openbsd.org091c3022015-01-19 19:52:16 +0000598 state->initialized = 0;
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000599 if (do_close) {
600 if (state->connection_in == state->connection_out) {
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000601 close(state->connection_out);
602 } else {
603 close(state->connection_in);
604 close(state->connection_out);
605 }
Damien Miller95def091999-11-25 00:26:21 +1100606 }
markus@openbsd.org091c3022015-01-19 19:52:16 +0000607 sshbuf_free(state->input);
608 sshbuf_free(state->output);
609 sshbuf_free(state->outgoing_packet);
610 sshbuf_free(state->incoming_packet);
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000611 for (mode = 0; mode < MODE_MAX; mode++) {
612 kex_free_newkeys(state->newkeys[mode]); /* current keys */
613 state->newkeys[mode] = NULL;
614 ssh_clear_newkeys(ssh, mode); /* next keys */
615 }
dtucker@openbsd.org7f8e66f2020-01-23 10:24:29 +0000616#ifdef WITH_ZLIB
dtucker@openbsd.orgfbce7c12020-01-23 10:53:04 +0000617 /* compression state is in shared mem, so we can only release it once */
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000618 if (do_close && state->compression_buffer) {
markus@openbsd.org091c3022015-01-19 19:52:16 +0000619 sshbuf_free(state->compression_buffer);
620 if (state->compression_out_started) {
621 z_streamp stream = &state->compression_out_stream;
622 debug("compress outgoing: "
623 "raw data %llu, compressed %llu, factor %.2f",
624 (unsigned long long)stream->total_in,
625 (unsigned long long)stream->total_out,
626 stream->total_in == 0 ? 0.0 :
627 (double) stream->total_out / stream->total_in);
628 if (state->compression_out_failures == 0)
629 deflateEnd(stream);
630 }
631 if (state->compression_in_started) {
dtucker@openbsd.org550c0532017-06-06 09:12:17 +0000632 z_streamp stream = &state->compression_in_stream;
markus@openbsd.org091c3022015-01-19 19:52:16 +0000633 debug("compress incoming: "
634 "raw data %llu, compressed %llu, factor %.2f",
635 (unsigned long long)stream->total_out,
636 (unsigned long long)stream->total_in,
637 stream->total_out == 0 ? 0.0 :
638 (double) stream->total_in / stream->total_out);
639 if (state->compression_in_failures == 0)
640 inflateEnd(stream);
641 }
Damien Miller95def091999-11-25 00:26:21 +1100642 }
dtucker@openbsd.org7f8e66f2020-01-23 10:24:29 +0000643#endif /* WITH_ZLIB */
djm@openbsd.org4706c1d2016-08-03 05:41:57 +0000644 cipher_free(state->send_context);
645 cipher_free(state->receive_context);
646 state->send_context = state->receive_context = NULL;
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000647 if (do_close) {
djm@openbsd.orgde2997a2018-07-16 03:09:13 +0000648 free(ssh->local_ipaddr);
649 ssh->local_ipaddr = NULL;
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000650 free(ssh->remote_ipaddr);
651 ssh->remote_ipaddr = NULL;
652 free(ssh->state);
653 ssh->state = NULL;
654 }
655}
656
657void
658ssh_packet_close(struct ssh *ssh)
659{
660 ssh_packet_close_internal(ssh, 1);
661}
662
663void
664ssh_packet_clear_keys(struct ssh *ssh)
665{
666 ssh_packet_close_internal(ssh, 0);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000667}
668
669/* Sets remote side protocol flags. */
670
671void
markus@openbsd.org091c3022015-01-19 19:52:16 +0000672ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000673{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000674 ssh->state->remote_protocol_flags = protocol_flags;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000675}
676
677/* Returns the remote protocol flags set earlier by the above function. */
678
Ben Lindstrom46c16222000-12-22 01:43:59 +0000679u_int
markus@openbsd.org091c3022015-01-19 19:52:16 +0000680ssh_packet_get_protocol_flags(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000681{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000682 return ssh->state->remote_protocol_flags;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000683}
684
Damien Miller5428f641999-11-25 11:54:57 +1100685/*
686 * Starts packet compression from the next packet on in both directions.
687 * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
688 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000689
markus@openbsd.org091c3022015-01-19 19:52:16 +0000690static int
691ssh_packet_init_compression(struct ssh *ssh)
Ben Lindstromfb50cdf2001-04-05 23:20:46 +0000692{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000693 if (!ssh->state->compression_buffer &&
694 ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
695 return SSH_ERR_ALLOC_FAIL;
696 return 0;
697}
698
dtucker@openbsd.org7f8e66f2020-01-23 10:24:29 +0000699#ifdef WITH_ZLIB
markus@openbsd.org091c3022015-01-19 19:52:16 +0000700static int
701start_compression_out(struct ssh *ssh, int level)
702{
703 if (level < 1 || level > 9)
704 return SSH_ERR_INVALID_ARGUMENT;
705 debug("Enabling compression at level %d.", level);
706 if (ssh->state->compression_out_started == 1)
707 deflateEnd(&ssh->state->compression_out_stream);
708 switch (deflateInit(&ssh->state->compression_out_stream, level)) {
709 case Z_OK:
710 ssh->state->compression_out_started = 1;
711 break;
712 case Z_MEM_ERROR:
713 return SSH_ERR_ALLOC_FAIL;
714 default:
715 return SSH_ERR_INTERNAL_ERROR;
716 }
717 return 0;
718}
719
720static int
721start_compression_in(struct ssh *ssh)
722{
723 if (ssh->state->compression_in_started == 1)
724 inflateEnd(&ssh->state->compression_in_stream);
725 switch (inflateInit(&ssh->state->compression_in_stream)) {
726 case Z_OK:
727 ssh->state->compression_in_started = 1;
728 break;
729 case Z_MEM_ERROR:
730 return SSH_ERR_ALLOC_FAIL;
731 default:
732 return SSH_ERR_INTERNAL_ERROR;
733 }
734 return 0;
735}
736
markus@openbsd.org091c3022015-01-19 19:52:16 +0000737/* XXX remove need for separate compression buffer */
738static int
739compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
740{
741 u_char buf[4096];
742 int r, status;
743
744 if (ssh->state->compression_out_started != 1)
745 return SSH_ERR_INTERNAL_ERROR;
746
747 /* This case is not handled below. */
748 if (sshbuf_len(in) == 0)
749 return 0;
750
751 /* Input is the contents of the input buffer. */
752 if ((ssh->state->compression_out_stream.next_in =
753 sshbuf_mutable_ptr(in)) == NULL)
754 return SSH_ERR_INTERNAL_ERROR;
755 ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
756
757 /* Loop compressing until deflate() returns with avail_out != 0. */
758 do {
759 /* Set up fixed-size output buffer. */
760 ssh->state->compression_out_stream.next_out = buf;
761 ssh->state->compression_out_stream.avail_out = sizeof(buf);
762
763 /* Compress as much data into the buffer as possible. */
764 status = deflate(&ssh->state->compression_out_stream,
765 Z_PARTIAL_FLUSH);
766 switch (status) {
767 case Z_MEM_ERROR:
768 return SSH_ERR_ALLOC_FAIL;
769 case Z_OK:
770 /* Append compressed data to output_buffer. */
771 if ((r = sshbuf_put(out, buf, sizeof(buf) -
772 ssh->state->compression_out_stream.avail_out)) != 0)
773 return r;
774 break;
775 case Z_STREAM_ERROR:
776 default:
777 ssh->state->compression_out_failures++;
778 return SSH_ERR_INVALID_FORMAT;
779 }
780 } while (ssh->state->compression_out_stream.avail_out == 0);
781 return 0;
782}
783
784static int
785uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
786{
787 u_char buf[4096];
788 int r, status;
789
790 if (ssh->state->compression_in_started != 1)
791 return SSH_ERR_INTERNAL_ERROR;
792
793 if ((ssh->state->compression_in_stream.next_in =
794 sshbuf_mutable_ptr(in)) == NULL)
795 return SSH_ERR_INTERNAL_ERROR;
796 ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
797
798 for (;;) {
799 /* Set up fixed-size output buffer. */
800 ssh->state->compression_in_stream.next_out = buf;
801 ssh->state->compression_in_stream.avail_out = sizeof(buf);
802
803 status = inflate(&ssh->state->compression_in_stream,
804 Z_PARTIAL_FLUSH);
805 switch (status) {
806 case Z_OK:
807 if ((r = sshbuf_put(out, buf, sizeof(buf) -
808 ssh->state->compression_in_stream.avail_out)) != 0)
809 return r;
810 break;
811 case Z_BUF_ERROR:
812 /*
813 * Comments in zlib.h say that we should keep calling
814 * inflate() until we get an error. This appears to
815 * be the error that we get.
816 */
817 return 0;
818 case Z_DATA_ERROR:
819 return SSH_ERR_INVALID_FORMAT;
820 case Z_MEM_ERROR:
821 return SSH_ERR_ALLOC_FAIL;
822 case Z_STREAM_ERROR:
823 default:
824 ssh->state->compression_in_failures++;
825 return SSH_ERR_INTERNAL_ERROR;
826 }
827 }
828 /* NOTREACHED */
829}
830
dtucker@openbsd.org7f8e66f2020-01-23 10:24:29 +0000831#else /* WITH_ZLIB */
832
833static int
834start_compression_out(struct ssh *ssh, int level)
835{
836 return SSH_ERR_INTERNAL_ERROR;
837}
838
839static int
840start_compression_in(struct ssh *ssh)
841{
842 return SSH_ERR_INTERNAL_ERROR;
843}
844
845static int
846compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
847{
848 return SSH_ERR_INTERNAL_ERROR;
849}
850
851static int
852uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
853{
854 return SSH_ERR_INTERNAL_ERROR;
855}
856#endif /* WITH_ZLIB */
857
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000858void
859ssh_clear_newkeys(struct ssh *ssh, int mode)
860{
djm@openbsd.org2d75d742017-06-01 06:16:43 +0000861 if (ssh->kex && ssh->kex->newkeys[mode]) {
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000862 kex_free_newkeys(ssh->kex->newkeys[mode]);
863 ssh->kex->newkeys[mode] = NULL;
864 }
865}
866
markus@openbsd.org091c3022015-01-19 19:52:16 +0000867int
868ssh_set_newkeys(struct ssh *ssh, int mode)
Ben Lindstrom2d90e002001-04-04 02:00:54 +0000869{
markus@openbsd.org091c3022015-01-19 19:52:16 +0000870 struct session_state *state = ssh->state;
871 struct sshenc *enc;
872 struct sshmac *mac;
873 struct sshcomp *comp;
djm@openbsd.org4706c1d2016-08-03 05:41:57 +0000874 struct sshcipher_ctx **ccp;
markus@openbsd.org06ce56b2016-09-06 09:22:56 +0000875 struct packet_state *ps;
Damien Millera5539d22003-04-09 20:50:06 +1000876 u_int64_t *max_blocks;
djm@openbsd.org2d75d742017-06-01 06:16:43 +0000877 const char *wmsg;
Damien Miller86687062014-07-02 15:28:02 +1000878 int r, crypt_type;
djm@openbsd.orge9552d62019-03-01 03:29:32 +0000879 const char *dir = mode == MODE_OUT ? "out" : "in";
Ben Lindstrom2d90e002001-04-04 02:00:54 +0000880
Ben Lindstrom064496f2002-12-23 02:04:22 +0000881 debug2("set_newkeys: mode %d", mode);
Ben Lindstrom2d90e002001-04-04 02:00:54 +0000882
Damien Miller963f6b22002-02-19 15:21:23 +1100883 if (mode == MODE_OUT) {
djm@openbsd.org4706c1d2016-08-03 05:41:57 +0000884 ccp = &state->send_context;
Darren Tucker3f9fdc72004-06-22 12:56:01 +1000885 crypt_type = CIPHER_ENCRYPT;
markus@openbsd.org06ce56b2016-09-06 09:22:56 +0000886 ps = &state->p_send;
markus@openbsd.org091c3022015-01-19 19:52:16 +0000887 max_blocks = &state->max_blocks_out;
Damien Miller963f6b22002-02-19 15:21:23 +1100888 } else {
djm@openbsd.org4706c1d2016-08-03 05:41:57 +0000889 ccp = &state->receive_context;
Darren Tucker3f9fdc72004-06-22 12:56:01 +1000890 crypt_type = CIPHER_DECRYPT;
markus@openbsd.org06ce56b2016-09-06 09:22:56 +0000891 ps = &state->p_read;
markus@openbsd.org091c3022015-01-19 19:52:16 +0000892 max_blocks = &state->max_blocks_in;
Damien Miller963f6b22002-02-19 15:21:23 +1100893 }
markus@openbsd.org091c3022015-01-19 19:52:16 +0000894 if (state->newkeys[mode] != NULL) {
djm@openbsd.orge9552d62019-03-01 03:29:32 +0000895 debug("%s: rekeying %s, input %llu bytes %llu blocks, "
896 "output %llu bytes %llu blocks", __func__, dir,
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000897 (unsigned long long)state->p_read.bytes,
898 (unsigned long long)state->p_read.blocks,
899 (unsigned long long)state->p_send.bytes,
900 (unsigned long long)state->p_send.blocks);
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +0000901 kex_free_newkeys(state->newkeys[mode]);
902 state->newkeys[mode] = NULL;
Ben Lindstrom2d90e002001-04-04 02:00:54 +0000903 }
markus@openbsd.org06ce56b2016-09-06 09:22:56 +0000904 /* note that both bytes and the seqnr are not reset */
905 ps->packets = ps->blocks = 0;
markus@openbsd.org091c3022015-01-19 19:52:16 +0000906 /* move newkeys from kex to state */
907 if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
908 return SSH_ERR_INTERNAL_ERROR;
909 ssh->kex->newkeys[mode] = NULL;
910 enc = &state->newkeys[mode]->enc;
911 mac = &state->newkeys[mode]->mac;
912 comp = &state->newkeys[mode]->comp;
913 if (cipher_authlen(enc->cipher) == 0) {
914 if ((r = mac_init(mac)) != 0)
915 return r;
916 }
917 mac->enabled = 1;
djm@openbsd.orge9552d62019-03-01 03:29:32 +0000918 DBG(debug("%s: cipher_init_context: %s", __func__, dir));
djm@openbsd.org8a818342019-01-04 03:23:00 +0000919 cipher_free(*ccp);
920 *ccp = NULL;
djm@openbsd.org4706c1d2016-08-03 05:41:57 +0000921 if ((r = cipher_init(ccp, enc->cipher, enc->key, enc->key_len,
Damien Miller86687062014-07-02 15:28:02 +1000922 enc->iv, enc->iv_len, crypt_type)) != 0)
markus@openbsd.org091c3022015-01-19 19:52:16 +0000923 return r;
924 if (!state->cipher_warning_done &&
djm@openbsd.org4706c1d2016-08-03 05:41:57 +0000925 (wmsg = cipher_warning_message(*ccp)) != NULL) {
markus@openbsd.org091c3022015-01-19 19:52:16 +0000926 error("Warning: %s", wmsg);
927 state->cipher_warning_done = 1;
928 }
Ben Lindstromf6027d32002-03-22 01:42:04 +0000929 /* Deleting the keys does not gain extra security */
Damien Millera5103f42014-02-04 11:20:14 +1100930 /* explicit_bzero(enc->iv, enc->block_size);
931 explicit_bzero(enc->key, enc->key_len);
932 explicit_bzero(mac->key, mac->key_len); */
sf@openbsd.org168b46f2018-07-09 13:37:10 +0000933 if ((comp->type == COMP_ZLIB ||
934 (comp->type == COMP_DELAYED &&
935 state->after_authentication)) && comp->enabled == 0) {
markus@openbsd.org091c3022015-01-19 19:52:16 +0000936 if ((r = ssh_packet_init_compression(ssh)) < 0)
937 return r;
938 if (mode == MODE_OUT) {
939 if ((r = start_compression_out(ssh, 6)) != 0)
940 return r;
941 } else {
942 if ((r = start_compression_in(ssh)) != 0)
943 return r;
944 }
Ben Lindstrom2d90e002001-04-04 02:00:54 +0000945 comp->enabled = 1;
Ben Lindstrom2d90e002001-04-04 02:00:54 +0000946 }
Darren Tucker81a0b372003-07-14 17:31:06 +1000947 /*
948 * The 2^(blocksize*2) limit is too expensive for 3DES,
djm@openbsd.orgacaf34f2017-05-07 23:12:57 +0000949 * so enforce a 1GB limit for small blocksizes.
dtucker@openbsd.orgad053162017-06-09 04:40:04 +0000950 * See RFC4344 section 3.2.
Darren Tucker81a0b372003-07-14 17:31:06 +1000951 */
952 if (enc->block_size >= 16)
953 *max_blocks = (u_int64_t)1 << (enc->block_size*2);
954 else
955 *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
markus@openbsd.org091c3022015-01-19 19:52:16 +0000956 if (state->rekey_limit)
deraadt@openbsd.org9136ec12016-09-12 01:22:38 +0000957 *max_blocks = MINIMUM(*max_blocks,
markus@openbsd.org091c3022015-01-19 19:52:16 +0000958 state->rekey_limit / enc->block_size);
djm@openbsd.orge9552d62019-03-01 03:29:32 +0000959 debug("rekey %s after %llu blocks", dir,
960 (unsigned long long)*max_blocks);
markus@openbsd.org091c3022015-01-19 19:52:16 +0000961 return 0;
Ben Lindstrom2d90e002001-04-04 02:00:54 +0000962}
963
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +0000964#define MAX_PACKETS (1U<<31)
965static int
966ssh_packet_need_rekeying(struct ssh *ssh, u_int outbound_packet_len)
967{
968 struct session_state *state = ssh->state;
969 u_int32_t out_blocks;
970
971 /* XXX client can't cope with rekeying pre-auth */
972 if (!state->after_authentication)
973 return 0;
974
975 /* Haven't keyed yet or KEX in progress. */
djm@openbsd.org0a843d92018-12-27 03:25:24 +0000976 if (ssh_packet_is_rekeying(ssh))
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +0000977 return 0;
978
979 /* Peer can't rekey */
980 if (ssh->compat & SSH_BUG_NOREKEY)
981 return 0;
982
983 /*
984 * Permit one packet in or out per rekey - this allows us to
985 * make progress when rekey limits are very small.
986 */
987 if (state->p_send.packets == 0 && state->p_read.packets == 0)
988 return 0;
989
990 /* Time-based rekeying */
991 if (state->rekey_interval != 0 &&
dtucker@openbsd.orgc998bf02017-02-03 02:56:00 +0000992 (int64_t)state->rekey_time + state->rekey_interval <= monotime())
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +0000993 return 1;
994
dtucker@openbsd.orgad053162017-06-09 04:40:04 +0000995 /*
996 * Always rekey when MAX_PACKETS sent in either direction
997 * As per RFC4344 section 3.1 we do this after 2^31 packets.
998 */
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +0000999 if (state->p_send.packets > MAX_PACKETS ||
1000 state->p_read.packets > MAX_PACKETS)
1001 return 1;
1002
Damien Miller10479cc2018-04-10 10:19:02 +10001003 /* Rekey after (cipher-specific) maximum blocks */
deraadt@openbsd.org9136ec12016-09-12 01:22:38 +00001004 out_blocks = ROUNDUP(outbound_packet_len,
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +00001005 state->newkeys[MODE_OUT]->enc.block_size);
1006 return (state->max_blocks_out &&
1007 (state->p_send.blocks + out_blocks > state->max_blocks_out)) ||
1008 (state->max_blocks_in &&
1009 (state->p_read.blocks > state->max_blocks_in));
1010}
1011
Damien Miller5428f641999-11-25 11:54:57 +11001012/*
Damien Miller9786e6e2005-07-26 21:54:56 +10001013 * Delayed compression for SSH2 is enabled after authentication:
Darren Tuckerf676c572006-08-05 18:51:08 +10001014 * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
Damien Miller9786e6e2005-07-26 21:54:56 +10001015 * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
1016 */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001017static int
1018ssh_packet_enable_delayed_compress(struct ssh *ssh)
Damien Miller9786e6e2005-07-26 21:54:56 +10001019{
markus@openbsd.org091c3022015-01-19 19:52:16 +00001020 struct session_state *state = ssh->state;
1021 struct sshcomp *comp = NULL;
1022 int r, mode;
Damien Miller9786e6e2005-07-26 21:54:56 +10001023
1024 /*
1025 * Remember that we are past the authentication step, so rekeying
sf@openbsd.org168b46f2018-07-09 13:37:10 +00001026 * with COMP_DELAYED will turn on compression immediately.
Damien Miller9786e6e2005-07-26 21:54:56 +10001027 */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001028 state->after_authentication = 1;
Damien Miller9786e6e2005-07-26 21:54:56 +10001029 for (mode = 0; mode < MODE_MAX; mode++) {
Darren Tucker4aa665b2006-09-21 13:00:25 +10001030 /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001031 if (state->newkeys[mode] == NULL)
Darren Tucker4aa665b2006-09-21 13:00:25 +10001032 continue;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001033 comp = &state->newkeys[mode]->comp;
sf@openbsd.org168b46f2018-07-09 13:37:10 +00001034 if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
markus@openbsd.org091c3022015-01-19 19:52:16 +00001035 if ((r = ssh_packet_init_compression(ssh)) != 0)
1036 return r;
1037 if (mode == MODE_OUT) {
1038 if ((r = start_compression_out(ssh, 6)) != 0)
1039 return r;
1040 } else {
1041 if ((r = start_compression_in(ssh)) != 0)
1042 return r;
1043 }
Damien Miller9786e6e2005-07-26 21:54:56 +10001044 comp->enabled = 1;
1045 }
1046 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001047 return 0;
Damien Miller9786e6e2005-07-26 21:54:56 +10001048}
1049
djm@openbsd.org28136472016-01-29 05:46:01 +00001050/* Used to mute debug logging for noisy packet types */
markus@openbsd.org8d057842016-09-30 09:19:13 +00001051int
djm@openbsd.org28136472016-01-29 05:46:01 +00001052ssh_packet_log_type(u_char type)
1053{
1054 switch (type) {
1055 case SSH2_MSG_CHANNEL_DATA:
1056 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1057 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1058 return 0;
1059 default:
1060 return 1;
1061 }
1062}
1063
Damien Miller9786e6e2005-07-26 21:54:56 +10001064/*
Damien Miller33b13562000-04-04 14:38:59 +10001065 * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1066 */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001067int
1068ssh_packet_send2_wrapped(struct ssh *ssh)
Damien Miller33b13562000-04-04 14:38:59 +10001069{
markus@openbsd.org091c3022015-01-19 19:52:16 +00001070 struct session_state *state = ssh->state;
markus@openbsd.org128343b2015-01-13 19:31:40 +00001071 u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
djm@openbsd.orgeb999a42016-07-18 06:08:01 +00001072 u_char tmp, padlen, pad = 0;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001073 u_int authlen = 0, aadlen = 0;
1074 u_int len;
1075 struct sshenc *enc = NULL;
1076 struct sshmac *mac = NULL;
1077 struct sshcomp *comp = NULL;
1078 int r, block_size;
Damien Miller33b13562000-04-04 14:38:59 +10001079
markus@openbsd.org091c3022015-01-19 19:52:16 +00001080 if (state->newkeys[MODE_OUT] != NULL) {
1081 enc = &state->newkeys[MODE_OUT]->enc;
1082 mac = &state->newkeys[MODE_OUT]->mac;
1083 comp = &state->newkeys[MODE_OUT]->comp;
Damien Miller1d75abf2013-01-09 16:12:19 +11001084 /* disable mac for authenticated encryption */
1085 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1086 mac = NULL;
Damien Miller33b13562000-04-04 14:38:59 +10001087 }
Damien Miller963f6b22002-02-19 15:21:23 +11001088 block_size = enc ? enc->block_size : 8;
Damien Miller1d75abf2013-01-09 16:12:19 +11001089 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
Damien Miller33b13562000-04-04 14:38:59 +10001090
markus@openbsd.org091c3022015-01-19 19:52:16 +00001091 type = (sshbuf_ptr(state->outgoing_packet))[5];
djm@openbsd.org28136472016-01-29 05:46:01 +00001092 if (ssh_packet_log_type(type))
1093 debug3("send packet: type %u", type);
Damien Miller33b13562000-04-04 14:38:59 +10001094#ifdef PACKET_DEBUG
1095 fprintf(stderr, "plain: ");
markus@openbsd.org091c3022015-01-19 19:52:16 +00001096 sshbuf_dump(state->outgoing_packet, stderr);
Damien Miller33b13562000-04-04 14:38:59 +10001097#endif
1098
1099 if (comp && comp->enabled) {
markus@openbsd.org091c3022015-01-19 19:52:16 +00001100 len = sshbuf_len(state->outgoing_packet);
Damien Miller33b13562000-04-04 14:38:59 +10001101 /* skip header, compress only payload */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001102 if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1103 goto out;
1104 sshbuf_reset(state->compression_buffer);
1105 if ((r = compress_buffer(ssh, state->outgoing_packet,
1106 state->compression_buffer)) != 0)
1107 goto out;
1108 sshbuf_reset(state->outgoing_packet);
1109 if ((r = sshbuf_put(state->outgoing_packet,
1110 "\0\0\0\0\0", 5)) != 0 ||
1111 (r = sshbuf_putb(state->outgoing_packet,
1112 state->compression_buffer)) != 0)
1113 goto out;
1114 DBG(debug("compression: raw %d compressed %zd", len,
1115 sshbuf_len(state->outgoing_packet)));
Damien Miller33b13562000-04-04 14:38:59 +10001116 }
1117
1118 /* sizeof (packet_len + pad_len + payload) */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001119 len = sshbuf_len(state->outgoing_packet);
Damien Miller33b13562000-04-04 14:38:59 +10001120
1121 /*
1122 * calc size of padding, alloc space, get random data,
1123 * minimum padding is 4 bytes
1124 */
Damien Milleraf43a7a2012-12-12 10:46:31 +11001125 len -= aadlen; /* packet length is not encrypted for EtM modes */
Damien Miller33b13562000-04-04 14:38:59 +10001126 padlen = block_size - (len % block_size);
1127 if (padlen < 4)
1128 padlen += block_size;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001129 if (state->extra_pad) {
djm@openbsd.orgeb999a42016-07-18 06:08:01 +00001130 tmp = state->extra_pad;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001131 state->extra_pad =
deraadt@openbsd.org9136ec12016-09-12 01:22:38 +00001132 ROUNDUP(state->extra_pad, block_size);
djm@openbsd.orgeb999a42016-07-18 06:08:01 +00001133 /* check if roundup overflowed */
1134 if (state->extra_pad < tmp)
1135 return SSH_ERR_INVALID_ARGUMENT;
1136 tmp = (len + padlen) % state->extra_pad;
1137 /* Check whether pad calculation below will underflow */
1138 if (tmp > state->extra_pad)
1139 return SSH_ERR_INVALID_ARGUMENT;
1140 pad = state->extra_pad - tmp;
Damien Miller2a328432014-04-20 13:24:01 +10001141 DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
markus@openbsd.org091c3022015-01-19 19:52:16 +00001142 __func__, pad, len, padlen, state->extra_pad));
djm@openbsd.orgeb999a42016-07-18 06:08:01 +00001143 tmp = padlen;
Damien Miller9f643902001-11-12 11:02:52 +11001144 padlen += pad;
djm@openbsd.orgeb999a42016-07-18 06:08:01 +00001145 /* Check whether padlen calculation overflowed */
1146 if (padlen < tmp)
1147 return SSH_ERR_INVALID_ARGUMENT; /* overflow */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001148 state->extra_pad = 0;
Damien Miller9f643902001-11-12 11:02:52 +11001149 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001150 if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1151 goto out;
djm@openbsd.org4706c1d2016-08-03 05:41:57 +00001152 if (enc && !cipher_ctx_is_plaintext(state->send_context)) {
Damien Millere247cc42000-05-07 12:03:14 +10001153 /* random padding */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001154 arc4random_buf(cp, padlen);
Damien Millere247cc42000-05-07 12:03:14 +10001155 } else {
1156 /* clear padding */
Damien Millera5103f42014-02-04 11:20:14 +11001157 explicit_bzero(cp, padlen);
Damien Miller33b13562000-04-04 14:38:59 +10001158 }
Damien Milleraf43a7a2012-12-12 10:46:31 +11001159 /* sizeof (packet_len + pad_len + payload + padding) */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001160 len = sshbuf_len(state->outgoing_packet);
1161 cp = sshbuf_mutable_ptr(state->outgoing_packet);
1162 if (cp == NULL) {
1163 r = SSH_ERR_INTERNAL_ERROR;
1164 goto out;
1165 }
Damien Milleraf43a7a2012-12-12 10:46:31 +11001166 /* packet_length includes payload, padding and padding length field */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001167 POKE_U32(cp, len - 4);
Ben Lindstrom4a7714a2002-02-26 18:04:38 +00001168 cp[4] = padlen;
Damien Milleraf43a7a2012-12-12 10:46:31 +11001169 DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1170 len, padlen, aadlen));
Damien Miller33b13562000-04-04 14:38:59 +10001171
1172 /* compute MAC over seqnr and packet(length fields, payload, padding) */
Damien Milleraf43a7a2012-12-12 10:46:31 +11001173 if (mac && mac->enabled && !mac->etm) {
markus@openbsd.org091c3022015-01-19 19:52:16 +00001174 if ((r = mac_compute(mac, state->p_send.seqnr,
1175 sshbuf_ptr(state->outgoing_packet), len,
markus@openbsd.org128343b2015-01-13 19:31:40 +00001176 macbuf, sizeof(macbuf))) != 0)
markus@openbsd.org091c3022015-01-19 19:52:16 +00001177 goto out;
1178 DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
Damien Miller33b13562000-04-04 14:38:59 +10001179 }
1180 /* encrypt packet and append to output buffer. */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001181 if ((r = sshbuf_reserve(state->output,
1182 sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1183 goto out;
djm@openbsd.org4706c1d2016-08-03 05:41:57 +00001184 if ((r = cipher_crypt(state->send_context, state->p_send.seqnr, cp,
markus@openbsd.org091c3022015-01-19 19:52:16 +00001185 sshbuf_ptr(state->outgoing_packet),
1186 len - aadlen, aadlen, authlen)) != 0)
1187 goto out;
Damien Miller33b13562000-04-04 14:38:59 +10001188 /* append unencrypted MAC */
Damien Milleraf43a7a2012-12-12 10:46:31 +11001189 if (mac && mac->enabled) {
1190 if (mac->etm) {
1191 /* EtM: compute mac over aadlen + cipher text */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001192 if ((r = mac_compute(mac, state->p_send.seqnr,
1193 cp, len, macbuf, sizeof(macbuf))) != 0)
1194 goto out;
Damien Milleraf43a7a2012-12-12 10:46:31 +11001195 DBG(debug("done calc MAC(EtM) out #%d",
markus@openbsd.org091c3022015-01-19 19:52:16 +00001196 state->p_send.seqnr));
Damien Milleraf43a7a2012-12-12 10:46:31 +11001197 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001198 if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1199 goto out;
Damien Milleraf43a7a2012-12-12 10:46:31 +11001200 }
Damien Miller33b13562000-04-04 14:38:59 +10001201#ifdef PACKET_DEBUG
1202 fprintf(stderr, "encrypted: ");
markus@openbsd.org091c3022015-01-19 19:52:16 +00001203 sshbuf_dump(state->output, stderr);
Damien Miller33b13562000-04-04 14:38:59 +10001204#endif
Damien Miller4af51302000-04-16 11:18:38 +10001205 /* increment sequence number for outgoing packets */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001206 if (++state->p_send.seqnr == 0)
Damien Miller996acd22003-04-09 20:59:48 +10001207 logit("outgoing seqnr wraps around");
markus@openbsd.org091c3022015-01-19 19:52:16 +00001208 if (++state->p_send.packets == 0)
1209 if (!(ssh->compat & SSH_BUG_NOREKEY))
1210 return SSH_ERR_NEED_REKEY;
1211 state->p_send.blocks += len / block_size;
1212 state->p_send.bytes += len;
1213 sshbuf_reset(state->outgoing_packet);
Damien Miller33b13562000-04-04 14:38:59 +10001214
Ben Lindstrom2d90e002001-04-04 02:00:54 +00001215 if (type == SSH2_MSG_NEWKEYS)
markus@openbsd.org091c3022015-01-19 19:52:16 +00001216 r = ssh_set_newkeys(ssh, MODE_OUT);
1217 else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1218 r = ssh_packet_enable_delayed_compress(ssh);
1219 else
1220 r = 0;
1221 out:
1222 return r;
Damien Miller33b13562000-04-04 14:38:59 +10001223}
1224
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +00001225/* returns non-zero if the specified packet type is usec by KEX */
1226static int
1227ssh_packet_type_is_kex(u_char type)
1228{
1229 return
1230 type >= SSH2_MSG_TRANSPORT_MIN &&
1231 type <= SSH2_MSG_TRANSPORT_MAX &&
1232 type != SSH2_MSG_SERVICE_REQUEST &&
1233 type != SSH2_MSG_SERVICE_ACCEPT &&
1234 type != SSH2_MSG_EXT_INFO;
1235}
1236
markus@openbsd.org091c3022015-01-19 19:52:16 +00001237int
1238ssh_packet_send2(struct ssh *ssh)
Damien Millera5539d22003-04-09 20:50:06 +10001239{
markus@openbsd.org091c3022015-01-19 19:52:16 +00001240 struct session_state *state = ssh->state;
Damien Millera5539d22003-04-09 20:50:06 +10001241 struct packet *p;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001242 u_char type;
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +00001243 int r, need_rekey;
Damien Millera5539d22003-04-09 20:50:06 +10001244
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +00001245 if (sshbuf_len(state->outgoing_packet) < 6)
1246 return SSH_ERR_INTERNAL_ERROR;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001247 type = sshbuf_ptr(state->outgoing_packet)[5];
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +00001248 need_rekey = !ssh_packet_type_is_kex(type) &&
1249 ssh_packet_need_rekeying(ssh, sshbuf_len(state->outgoing_packet));
Damien Millera5539d22003-04-09 20:50:06 +10001250
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +00001251 /*
1252 * During rekeying we can only send key exchange messages.
1253 * Queue everything else.
1254 */
1255 if ((need_rekey || state->rekeying) && !ssh_packet_type_is_kex(type)) {
1256 if (need_rekey)
1257 debug3("%s: rekex triggered", __func__);
1258 debug("enqueue packet: %u", type);
1259 p = calloc(1, sizeof(*p));
1260 if (p == NULL)
1261 return SSH_ERR_ALLOC_FAIL;
1262 p->type = type;
1263 p->payload = state->outgoing_packet;
1264 TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1265 state->outgoing_packet = sshbuf_new();
1266 if (state->outgoing_packet == NULL)
1267 return SSH_ERR_ALLOC_FAIL;
1268 if (need_rekey) {
1269 /*
1270 * This packet triggered a rekey, so send the
1271 * KEXINIT now.
1272 * NB. reenters this function via kex_start_rekex().
1273 */
1274 return kex_start_rekex(ssh);
Damien Millera5539d22003-04-09 20:50:06 +10001275 }
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +00001276 return 0;
Damien Millera5539d22003-04-09 20:50:06 +10001277 }
1278
1279 /* rekeying starts with sending KEXINIT */
1280 if (type == SSH2_MSG_KEXINIT)
markus@openbsd.org091c3022015-01-19 19:52:16 +00001281 state->rekeying = 1;
Damien Millera5539d22003-04-09 20:50:06 +10001282
markus@openbsd.org091c3022015-01-19 19:52:16 +00001283 if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1284 return r;
Damien Millera5539d22003-04-09 20:50:06 +10001285
1286 /* after a NEWKEYS message we can send the complete queue */
1287 if (type == SSH2_MSG_NEWKEYS) {
markus@openbsd.org091c3022015-01-19 19:52:16 +00001288 state->rekeying = 0;
1289 state->rekey_time = monotime();
1290 while ((p = TAILQ_FIRST(&state->outgoing))) {
Damien Millera5539d22003-04-09 20:50:06 +10001291 type = p->type;
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +00001292 /*
1293 * If this packet triggers a rekex, then skip the
1294 * remaining packets in the queue for now.
1295 * NB. re-enters this function via kex_start_rekex.
1296 */
1297 if (ssh_packet_need_rekeying(ssh,
1298 sshbuf_len(p->payload))) {
1299 debug3("%s: queued packet triggered rekex",
1300 __func__);
1301 return kex_start_rekex(ssh);
1302 }
Damien Millera5539d22003-04-09 20:50:06 +10001303 debug("dequeue packet: %u", type);
markus@openbsd.org091c3022015-01-19 19:52:16 +00001304 sshbuf_free(state->outgoing_packet);
1305 state->outgoing_packet = p->payload;
1306 TAILQ_REMOVE(&state->outgoing, p, next);
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +00001307 memset(p, 0, sizeof(*p));
Darren Tuckera627d422013-06-02 07:31:17 +10001308 free(p);
markus@openbsd.org091c3022015-01-19 19:52:16 +00001309 if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1310 return r;
Damien Millera5539d22003-04-09 20:50:06 +10001311 }
1312 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001313 return 0;
Damien Miller33b13562000-04-04 14:38:59 +10001314}
1315
Damien Miller33b13562000-04-04 14:38:59 +10001316/*
Damien Miller5428f641999-11-25 11:54:57 +11001317 * Waits until a packet has been received, and returns its type. Note that
1318 * no other data is processed until this returns, so this function should not
1319 * be used during the interactive session.
1320 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001321
1322int
markus@openbsd.org091c3022015-01-19 19:52:16 +00001323ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001324{
markus@openbsd.org091c3022015-01-19 19:52:16 +00001325 struct session_state *state = ssh->state;
markus@openbsd.orga3068632016-01-14 16:17:39 +00001326 int len, r, ms_remain;
Ben Lindstromcb978aa2001-03-05 07:07:49 +00001327 fd_set *setp;
Damien Miller95def091999-11-25 00:26:21 +11001328 char buf[8192];
Darren Tucker3fc464e2008-06-13 06:42:45 +10001329 struct timeval timeout, start, *timeoutp = NULL;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001330
Darren Tucker99bb7612008-06-13 22:02:50 +10001331 DBG(debug("packet_read()"));
1332
deraadt@openbsd.orgce445b02015-08-20 22:32:42 +00001333 setp = calloc(howmany(state->connection_in + 1,
Darren Tuckerf7288d72009-06-21 18:12:20 +10001334 NFDBITS), sizeof(fd_mask));
markus@openbsd.org091c3022015-01-19 19:52:16 +00001335 if (setp == NULL)
1336 return SSH_ERR_ALLOC_FAIL;
Ben Lindstromcb978aa2001-03-05 07:07:49 +00001337
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001338 /*
1339 * Since we are blocking, ensure that all written packets have
1340 * been sent.
1341 */
markus@openbsd.org4daeb672015-03-24 20:10:08 +00001342 if ((r = ssh_packet_write_wait(ssh)) != 0)
1343 goto out;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001344
Damien Miller95def091999-11-25 00:26:21 +11001345 /* Stay in the loop until we have received a complete packet. */
1346 for (;;) {
1347 /* Try to read a packet from the buffer. */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001348 r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1349 if (r != 0)
1350 break;
Damien Miller95def091999-11-25 00:26:21 +11001351 /* If we got a packet, return it. */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001352 if (*typep != SSH_MSG_NONE)
1353 break;
Damien Miller5428f641999-11-25 11:54:57 +11001354 /*
1355 * Otherwise, wait for some data to arrive, add it to the
1356 * buffer, and try again.
1357 */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001358 memset(setp, 0, howmany(state->connection_in + 1,
Darren Tuckerf7288d72009-06-21 18:12:20 +10001359 NFDBITS) * sizeof(fd_mask));
markus@openbsd.org091c3022015-01-19 19:52:16 +00001360 FD_SET(state->connection_in, setp);
Damien Miller5428f641999-11-25 11:54:57 +11001361
markus@openbsd.org091c3022015-01-19 19:52:16 +00001362 if (state->packet_timeout_ms > 0) {
1363 ms_remain = state->packet_timeout_ms;
Darren Tucker3fc464e2008-06-13 06:42:45 +10001364 timeoutp = &timeout;
1365 }
Damien Miller95def091999-11-25 00:26:21 +11001366 /* Wait for some data to arrive. */
Darren Tucker3fc464e2008-06-13 06:42:45 +10001367 for (;;) {
markus@openbsd.org091c3022015-01-19 19:52:16 +00001368 if (state->packet_timeout_ms != -1) {
Darren Tucker3fc464e2008-06-13 06:42:45 +10001369 ms_to_timeval(&timeout, ms_remain);
dtucker@openbsd.org@openbsd.org5db6fbf2017-11-25 06:46:22 +00001370 monotime_tv(&start);
Darren Tucker3fc464e2008-06-13 06:42:45 +10001371 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001372 if ((r = select(state->connection_in + 1, setp,
Darren Tuckerf7288d72009-06-21 18:12:20 +10001373 NULL, NULL, timeoutp)) >= 0)
Darren Tucker3fc464e2008-06-13 06:42:45 +10001374 break;
Damien Millerea437422009-10-02 11:49:03 +10001375 if (errno != EAGAIN && errno != EINTR &&
dtucker@openbsd.org1da59342018-05-25 03:20:59 +00001376 errno != EWOULDBLOCK) {
1377 r = SSH_ERR_SYSTEM_ERROR;
1378 goto out;
1379 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001380 if (state->packet_timeout_ms == -1)
Darren Tucker3fc464e2008-06-13 06:42:45 +10001381 continue;
1382 ms_subtract_diff(&start, &ms_remain);
1383 if (ms_remain <= 0) {
markus@openbsd.org091c3022015-01-19 19:52:16 +00001384 r = 0;
Darren Tucker3fc464e2008-06-13 06:42:45 +10001385 break;
1386 }
1387 }
djm@openbsd.orgd7abb772017-02-28 06:10:08 +00001388 if (r == 0) {
1389 r = SSH_ERR_CONN_TIMEOUT;
1390 goto out;
1391 }
Damien Miller95def091999-11-25 00:26:21 +11001392 /* Read data from the socket. */
markus@openbsd.orga3068632016-01-14 16:17:39 +00001393 len = read(state->connection_in, buf, sizeof(buf));
markus@openbsd.org4daeb672015-03-24 20:10:08 +00001394 if (len == 0) {
1395 r = SSH_ERR_CONN_CLOSED;
1396 goto out;
1397 }
deraadt@openbsd.org4d28fa72019-06-28 13:35:04 +00001398 if (len == -1) {
markus@openbsd.org4daeb672015-03-24 20:10:08 +00001399 r = SSH_ERR_SYSTEM_ERROR;
1400 goto out;
1401 }
djm@openbsd.orgfae7bbe2015-01-28 21:15:47 +00001402
Damien Miller95def091999-11-25 00:26:21 +11001403 /* Append it to the buffer. */
djm@openbsd.orgfae7bbe2015-01-28 21:15:47 +00001404 if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
markus@openbsd.org4daeb672015-03-24 20:10:08 +00001405 goto out;
Damien Miller95def091999-11-25 00:26:21 +11001406 }
markus@openbsd.org4daeb672015-03-24 20:10:08 +00001407 out:
markus@openbsd.org091c3022015-01-19 19:52:16 +00001408 free(setp);
1409 return r;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001410}
1411
Damien Miller278f9072001-12-21 15:00:19 +11001412int
markus@openbsd.org091c3022015-01-19 19:52:16 +00001413ssh_packet_read(struct ssh *ssh)
Damien Miller278f9072001-12-21 15:00:19 +11001414{
markus@openbsd.org091c3022015-01-19 19:52:16 +00001415 u_char type;
1416 int r;
1417
1418 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1419 fatal("%s: %s", __func__, ssh_err(r));
1420 return type;
Damien Miller278f9072001-12-21 15:00:19 +11001421}
1422
Damien Miller5428f641999-11-25 11:54:57 +11001423/*
1424 * Waits until a packet has been received, verifies that its type matches
1425 * that given, and gives a fatal error and exits if there is a mismatch.
1426 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001427
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001428int
1429ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001430{
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001431 int r;
1432 u_char type;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001433
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001434 if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1435 return r;
1436 if (type != expected_type) {
1437 if ((r = sshpkt_disconnect(ssh,
markus@openbsd.org091c3022015-01-19 19:52:16 +00001438 "Protocol error: expected packet type %d, got %d",
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001439 expected_type, type)) != 0)
1440 return r;
1441 return SSH_ERR_PROTOCOL_ERROR;
1442 }
1443 return 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001444}
1445
markus@openbsd.org8d057842016-09-30 09:19:13 +00001446static int
1447ssh_packet_read_poll2_mux(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1448{
1449 struct session_state *state = ssh->state;
1450 const u_char *cp;
1451 size_t need;
1452 int r;
1453
1454 if (ssh->kex)
1455 return SSH_ERR_INTERNAL_ERROR;
1456 *typep = SSH_MSG_NONE;
1457 cp = sshbuf_ptr(state->input);
1458 if (state->packlen == 0) {
1459 if (sshbuf_len(state->input) < 4 + 1)
1460 return 0; /* packet is incomplete */
1461 state->packlen = PEEK_U32(cp);
1462 if (state->packlen < 4 + 1 ||
1463 state->packlen > PACKET_MAX_SIZE)
1464 return SSH_ERR_MESSAGE_INCOMPLETE;
1465 }
1466 need = state->packlen + 4;
1467 if (sshbuf_len(state->input) < need)
1468 return 0; /* packet is incomplete */
1469 sshbuf_reset(state->incoming_packet);
1470 if ((r = sshbuf_put(state->incoming_packet, cp + 4,
1471 state->packlen)) != 0 ||
1472 (r = sshbuf_consume(state->input, need)) != 0 ||
1473 (r = sshbuf_get_u8(state->incoming_packet, NULL)) != 0 ||
1474 (r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1475 return r;
1476 if (ssh_packet_log_type(*typep))
1477 debug3("%s: type %u", __func__, *typep);
1478 /* sshbuf_dump(state->incoming_packet, stderr); */
1479 /* reset for next packet */
1480 state->packlen = 0;
1481 return r;
1482}
1483
markus@openbsd.org091c3022015-01-19 19:52:16 +00001484int
1485ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
Damien Miller33b13562000-04-04 14:38:59 +10001486{
markus@openbsd.org091c3022015-01-19 19:52:16 +00001487 struct session_state *state = ssh->state;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001488 u_int padlen, need;
djm@openbsd.org6d311932016-07-08 03:44:42 +00001489 u_char *cp;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001490 u_int maclen, aadlen = 0, authlen = 0, block_size;
1491 struct sshenc *enc = NULL;
1492 struct sshmac *mac = NULL;
1493 struct sshcomp *comp = NULL;
markus@openbsd.org128343b2015-01-13 19:31:40 +00001494 int r;
Damien Miller33b13562000-04-04 14:38:59 +10001495
markus@openbsd.org8d057842016-09-30 09:19:13 +00001496 if (state->mux)
1497 return ssh_packet_read_poll2_mux(ssh, typep, seqnr_p);
1498
markus@openbsd.org091c3022015-01-19 19:52:16 +00001499 *typep = SSH_MSG_NONE;
Damien Miller13ae44c2009-01-28 16:38:41 +11001500
markus@openbsd.org091c3022015-01-19 19:52:16 +00001501 if (state->packet_discard)
1502 return 0;
1503
1504 if (state->newkeys[MODE_IN] != NULL) {
1505 enc = &state->newkeys[MODE_IN]->enc;
1506 mac = &state->newkeys[MODE_IN]->mac;
1507 comp = &state->newkeys[MODE_IN]->comp;
Damien Miller1d75abf2013-01-09 16:12:19 +11001508 /* disable mac for authenticated encryption */
1509 if ((authlen = cipher_authlen(enc->cipher)) != 0)
1510 mac = NULL;
Damien Miller33b13562000-04-04 14:38:59 +10001511 }
1512 maclen = mac && mac->enabled ? mac->mac_len : 0;
Damien Miller963f6b22002-02-19 15:21:23 +11001513 block_size = enc ? enc->block_size : 8;
Damien Miller1d75abf2013-01-09 16:12:19 +11001514 aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
Damien Miller33b13562000-04-04 14:38:59 +10001515
markus@openbsd.org091c3022015-01-19 19:52:16 +00001516 if (aadlen && state->packlen == 0) {
djm@openbsd.org4706c1d2016-08-03 05:41:57 +00001517 if (cipher_get_length(state->receive_context,
markus@openbsd.org091c3022015-01-19 19:52:16 +00001518 &state->packlen, state->p_read.seqnr,
1519 sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1520 return 0;
1521 if (state->packlen < 1 + 4 ||
1522 state->packlen > PACKET_MAX_SIZE) {
Damien Milleraf43a7a2012-12-12 10:46:31 +11001523#ifdef PACKET_DEBUG
markus@openbsd.org091c3022015-01-19 19:52:16 +00001524 sshbuf_dump(state->input, stderr);
Damien Milleraf43a7a2012-12-12 10:46:31 +11001525#endif
markus@openbsd.org091c3022015-01-19 19:52:16 +00001526 logit("Bad packet length %u.", state->packlen);
1527 if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1528 return r;
djm@openbsd.org2fecfd42015-11-08 21:59:11 +00001529 return SSH_ERR_CONN_CORRUPT;
Damien Milleraf43a7a2012-12-12 10:46:31 +11001530 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001531 sshbuf_reset(state->incoming_packet);
1532 } else if (state->packlen == 0) {
Damien Miller33b13562000-04-04 14:38:59 +10001533 /*
1534 * check if input size is less than the cipher block size,
1535 * decrypt first block and extract length of incoming packet
1536 */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001537 if (sshbuf_len(state->input) < block_size)
1538 return 0;
1539 sshbuf_reset(state->incoming_packet);
1540 if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1541 &cp)) != 0)
1542 goto out;
djm@openbsd.org4706c1d2016-08-03 05:41:57 +00001543 if ((r = cipher_crypt(state->receive_context,
markus@openbsd.org091c3022015-01-19 19:52:16 +00001544 state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1545 block_size, 0, 0)) != 0)
1546 goto out;
1547 state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1548 if (state->packlen < 1 + 4 ||
1549 state->packlen > PACKET_MAX_SIZE) {
Darren Tuckera8151da2003-09-22 21:06:46 +10001550#ifdef PACKET_DEBUG
markus@openbsd.org091c3022015-01-19 19:52:16 +00001551 fprintf(stderr, "input: \n");
1552 sshbuf_dump(state->input, stderr);
1553 fprintf(stderr, "incoming_packet: \n");
1554 sshbuf_dump(state->incoming_packet, stderr);
Darren Tuckera8151da2003-09-22 21:06:46 +10001555#endif
markus@openbsd.org091c3022015-01-19 19:52:16 +00001556 logit("Bad packet length %u.", state->packlen);
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +00001557 return ssh_packet_start_discard(ssh, enc, mac, 0,
1558 PACKET_MAX_SIZE);
Damien Miller33b13562000-04-04 14:38:59 +10001559 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001560 if ((r = sshbuf_consume(state->input, block_size)) != 0)
1561 goto out;
Damien Miller33b13562000-04-04 14:38:59 +10001562 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001563 DBG(debug("input: packet len %u", state->packlen+4));
1564
Damien Milleraf43a7a2012-12-12 10:46:31 +11001565 if (aadlen) {
1566 /* only the payload is encrypted */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001567 need = state->packlen;
Damien Milleraf43a7a2012-12-12 10:46:31 +11001568 } else {
1569 /*
1570 * the payload size and the payload are encrypted, but we
1571 * have a partial packet of block_size bytes
1572 */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001573 need = 4 + state->packlen - block_size;
Damien Milleraf43a7a2012-12-12 10:46:31 +11001574 }
Damien Miller1d75abf2013-01-09 16:12:19 +11001575 DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1576 " aadlen %d", block_size, need, maclen, authlen, aadlen));
Darren Tucker99d11a32008-12-01 21:40:48 +11001577 if (need % block_size != 0) {
1578 logit("padding error: need %d block %d mod %d",
Damien Miller33b13562000-04-04 14:38:59 +10001579 need, block_size, need % block_size);
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +00001580 return ssh_packet_start_discard(ssh, enc, mac, 0,
1581 PACKET_MAX_SIZE - block_size);
Darren Tucker99d11a32008-12-01 21:40:48 +11001582 }
Damien Miller33b13562000-04-04 14:38:59 +10001583 /*
1584 * check if the entire packet has been received and
Damien Milleraf43a7a2012-12-12 10:46:31 +11001585 * decrypt into incoming_packet:
1586 * 'aadlen' bytes are unencrypted, but authenticated.
Damien Miller1d75abf2013-01-09 16:12:19 +11001587 * 'need' bytes are encrypted, followed by either
1588 * 'authlen' bytes of authentication tag or
Damien Milleraf43a7a2012-12-12 10:46:31 +11001589 * 'maclen' bytes of message authentication code.
Damien Miller33b13562000-04-04 14:38:59 +10001590 */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001591 if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
djm@openbsd.org6d311932016-07-08 03:44:42 +00001592 return 0; /* packet is incomplete */
Damien Miller33b13562000-04-04 14:38:59 +10001593#ifdef PACKET_DEBUG
1594 fprintf(stderr, "read_poll enc/full: ");
markus@openbsd.org091c3022015-01-19 19:52:16 +00001595 sshbuf_dump(state->input, stderr);
Damien Miller33b13562000-04-04 14:38:59 +10001596#endif
djm@openbsd.org6d311932016-07-08 03:44:42 +00001597 /* EtM: check mac over encrypted input */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001598 if (mac && mac->enabled && mac->etm) {
djm@openbsd.org6d311932016-07-08 03:44:42 +00001599 if ((r = mac_check(mac, state->p_read.seqnr,
markus@openbsd.org091c3022015-01-19 19:52:16 +00001600 sshbuf_ptr(state->input), aadlen + need,
djm@openbsd.org6d311932016-07-08 03:44:42 +00001601 sshbuf_ptr(state->input) + aadlen + need + authlen,
1602 maclen)) != 0) {
1603 if (r == SSH_ERR_MAC_INVALID)
1604 logit("Corrupted MAC on input.");
markus@openbsd.org091c3022015-01-19 19:52:16 +00001605 goto out;
djm@openbsd.org6d311932016-07-08 03:44:42 +00001606 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001607 }
1608 if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1609 &cp)) != 0)
1610 goto out;
djm@openbsd.org4706c1d2016-08-03 05:41:57 +00001611 if ((r = cipher_crypt(state->receive_context, state->p_read.seqnr, cp,
markus@openbsd.org091c3022015-01-19 19:52:16 +00001612 sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1613 goto out;
1614 if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1615 goto out;
Damien Miller4af51302000-04-16 11:18:38 +10001616 if (mac && mac->enabled) {
djm@openbsd.org6d311932016-07-08 03:44:42 +00001617 /* Not EtM: check MAC over cleartext */
1618 if (!mac->etm && (r = mac_check(mac, state->p_read.seqnr,
1619 sshbuf_ptr(state->incoming_packet),
1620 sshbuf_len(state->incoming_packet),
1621 sshbuf_ptr(state->input), maclen)) != 0) {
1622 if (r != SSH_ERR_MAC_INVALID)
markus@openbsd.org091c3022015-01-19 19:52:16 +00001623 goto out;
Damien Miller13ae44c2009-01-28 16:38:41 +11001624 logit("Corrupted MAC on input.");
markus@openbsd.org0fb1a612017-03-11 13:07:35 +00001625 if (need + block_size > PACKET_MAX_SIZE)
markus@openbsd.org091c3022015-01-19 19:52:16 +00001626 return SSH_ERR_INTERNAL_ERROR;
1627 return ssh_packet_start_discard(ssh, enc, mac,
markus@openbsd.orgb98a2a82016-07-18 11:35:33 +00001628 sshbuf_len(state->incoming_packet),
markus@openbsd.org0fb1a612017-03-11 13:07:35 +00001629 PACKET_MAX_SIZE - need - block_size);
Damien Miller13ae44c2009-01-28 16:38:41 +11001630 }
djm@openbsd.org6d311932016-07-08 03:44:42 +00001631 /* Remove MAC from input buffer */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001632 DBG(debug("MAC #%d ok", state->p_read.seqnr));
1633 if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1634 goto out;
Damien Miller33b13562000-04-04 14:38:59 +10001635 }
Damien Miller278f9072001-12-21 15:00:19 +11001636 if (seqnr_p != NULL)
markus@openbsd.org091c3022015-01-19 19:52:16 +00001637 *seqnr_p = state->p_read.seqnr;
1638 if (++state->p_read.seqnr == 0)
Damien Miller996acd22003-04-09 20:59:48 +10001639 logit("incoming seqnr wraps around");
markus@openbsd.org091c3022015-01-19 19:52:16 +00001640 if (++state->p_read.packets == 0)
1641 if (!(ssh->compat & SSH_BUG_NOREKEY))
1642 return SSH_ERR_NEED_REKEY;
1643 state->p_read.blocks += (state->packlen + 4) / block_size;
1644 state->p_read.bytes += state->packlen + 4;
Damien Miller33b13562000-04-04 14:38:59 +10001645
1646 /* get padlen */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001647 padlen = sshbuf_ptr(state->incoming_packet)[4];
Damien Miller33b13562000-04-04 14:38:59 +10001648 DBG(debug("input: padlen %d", padlen));
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001649 if (padlen < 4) {
1650 if ((r = sshpkt_disconnect(ssh,
1651 "Corrupted padlen %d on input.", padlen)) != 0 ||
1652 (r = ssh_packet_write_wait(ssh)) != 0)
1653 return r;
1654 return SSH_ERR_CONN_CORRUPT;
1655 }
Damien Miller33b13562000-04-04 14:38:59 +10001656
1657 /* skip packet size + padlen, discard padding */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001658 if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1659 ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1660 goto out;
Damien Miller33b13562000-04-04 14:38:59 +10001661
markus@openbsd.org091c3022015-01-19 19:52:16 +00001662 DBG(debug("input: len before de-compress %zd",
1663 sshbuf_len(state->incoming_packet)));
Damien Miller33b13562000-04-04 14:38:59 +10001664 if (comp && comp->enabled) {
markus@openbsd.org091c3022015-01-19 19:52:16 +00001665 sshbuf_reset(state->compression_buffer);
1666 if ((r = uncompress_buffer(ssh, state->incoming_packet,
1667 state->compression_buffer)) != 0)
1668 goto out;
1669 sshbuf_reset(state->incoming_packet);
1670 if ((r = sshbuf_putb(state->incoming_packet,
1671 state->compression_buffer)) != 0)
1672 goto out;
1673 DBG(debug("input: len after de-compress %zd",
1674 sshbuf_len(state->incoming_packet)));
Damien Miller33b13562000-04-04 14:38:59 +10001675 }
1676 /*
1677 * get packet type, implies consume.
1678 * return length of payload (without type field)
1679 */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001680 if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1681 goto out;
djm@openbsd.org28136472016-01-29 05:46:01 +00001682 if (ssh_packet_log_type(*typep))
1683 debug3("receive packet: type %u", *typep);
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001684 if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1685 if ((r = sshpkt_disconnect(ssh,
1686 "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1687 (r = ssh_packet_write_wait(ssh)) != 0)
1688 return r;
1689 return SSH_ERR_PROTOCOL_ERROR;
1690 }
djm@openbsd.org39af7b42016-10-11 21:47:45 +00001691 if (state->hook_in != NULL &&
1692 (r = state->hook_in(ssh, state->incoming_packet, typep,
1693 state->hook_in_ctx)) != 0)
1694 return r;
markus@openbsd.org28652bc2016-09-19 19:02:19 +00001695 if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
markus@openbsd.org091c3022015-01-19 19:52:16 +00001696 r = ssh_packet_enable_delayed_compress(ssh);
1697 else
1698 r = 0;
Damien Miller33b13562000-04-04 14:38:59 +10001699#ifdef PACKET_DEBUG
markus@openbsd.org091c3022015-01-19 19:52:16 +00001700 fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1701 sshbuf_dump(state->incoming_packet, stderr);
Damien Miller33b13562000-04-04 14:38:59 +10001702#endif
Ben Lindstrom80c6d772001-06-05 21:09:18 +00001703 /* reset for next packet */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001704 state->packlen = 0;
djm@openbsd.org19bcf2e2016-02-08 10:57:07 +00001705
1706 /* do we need to rekey? */
1707 if (ssh_packet_need_rekeying(ssh, 0)) {
1708 debug3("%s: rekex triggered", __func__);
1709 if ((r = kex_start_rekex(ssh)) != 0)
1710 return r;
1711 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001712 out:
1713 return r;
Damien Miller33b13562000-04-04 14:38:59 +10001714}
1715
1716int
markus@openbsd.org091c3022015-01-19 19:52:16 +00001717ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
Damien Miller33b13562000-04-04 14:38:59 +10001718{
markus@openbsd.org091c3022015-01-19 19:52:16 +00001719 struct session_state *state = ssh->state;
Ben Lindstrom3f584742002-06-23 21:49:25 +00001720 u_int reason, seqnr;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001721 int r;
1722 u_char *msg;
Damien Miller33b13562000-04-04 14:38:59 +10001723
Ben Lindstrom80c6d772001-06-05 21:09:18 +00001724 for (;;) {
markus@openbsd.org091c3022015-01-19 19:52:16 +00001725 msg = NULL;
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001726 r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1727 if (r != 0)
1728 return r;
1729 if (*typep) {
1730 state->keep_alive_timeouts = 0;
1731 DBG(debug("received packet type %d", *typep));
1732 }
1733 switch (*typep) {
1734 case SSH2_MSG_IGNORE:
1735 debug3("Received SSH2_MSG_IGNORE");
1736 break;
1737 case SSH2_MSG_DEBUG:
1738 if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1739 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1740 (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1741 free(msg);
markus@openbsd.org091c3022015-01-19 19:52:16 +00001742 return r;
Darren Tucker136e56f2008-06-08 12:49:30 +10001743 }
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001744 debug("Remote: %.900s", msg);
1745 free(msg);
1746 break;
1747 case SSH2_MSG_DISCONNECT:
1748 if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1749 (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1750 return r;
1751 /* Ignore normal client exit notifications */
1752 do_log2(ssh->state->server_side &&
1753 reason == SSH2_DISCONNECT_BY_APPLICATION ?
1754 SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1755 "Received disconnect from %s port %d:"
1756 "%u: %.400s", ssh_remote_ipaddr(ssh),
1757 ssh_remote_port(ssh), reason, msg);
1758 free(msg);
1759 return SSH_ERR_DISCONNECTED;
1760 case SSH2_MSG_UNIMPLEMENTED:
1761 if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1762 return r;
1763 debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1764 seqnr);
1765 break;
1766 default:
1767 return 0;
Damien Miller33b13562000-04-04 14:38:59 +10001768 }
1769 }
1770}
1771
Damien Miller5428f641999-11-25 11:54:57 +11001772/*
1773 * Buffers the given amount of input characters. This is intended to be used
1774 * together with packet_read_poll.
1775 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001776
djm@openbsd.orgfae7bbe2015-01-28 21:15:47 +00001777int
markus@openbsd.org091c3022015-01-19 19:52:16 +00001778ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001779{
markus@openbsd.org091c3022015-01-19 19:52:16 +00001780 struct session_state *state = ssh->state;
1781 int r;
1782
1783 if (state->packet_discard) {
1784 state->keep_alive_timeouts = 0; /* ?? */
1785 if (len >= state->packet_discard) {
1786 if ((r = ssh_packet_stop_discard(ssh)) != 0)
djm@openbsd.orgfae7bbe2015-01-28 21:15:47 +00001787 return r;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001788 }
1789 state->packet_discard -= len;
djm@openbsd.orgfae7bbe2015-01-28 21:15:47 +00001790 return 0;
Damien Miller13ae44c2009-01-28 16:38:41 +11001791 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00001792 if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
djm@openbsd.orgfae7bbe2015-01-28 21:15:47 +00001793 return r;
1794
1795 return 0;
Damien Miller33b13562000-04-04 14:38:59 +10001796}
1797
Damien Miller4af51302000-04-16 11:18:38 +10001798int
markus@openbsd.org091c3022015-01-19 19:52:16 +00001799ssh_packet_remaining(struct ssh *ssh)
Damien Miller4af51302000-04-16 11:18:38 +10001800{
markus@openbsd.org091c3022015-01-19 19:52:16 +00001801 return sshbuf_len(ssh->state->incoming_packet);
Damien Millerda108ec2010-08-31 22:36:39 +10001802}
1803
Damien Miller5428f641999-11-25 11:54:57 +11001804/*
1805 * Sends a diagnostic message from the server to the client. This message
1806 * can be sent at any time (but not while constructing another message). The
1807 * message is printed immediately, but only if the client is being executed
1808 * in verbose mode. These messages are primarily intended to ease debugging
1809 * authentication problems. The length of the formatted message must not
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001810 * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
Damien Miller5428f641999-11-25 11:54:57 +11001811 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001812void
markus@openbsd.org091c3022015-01-19 19:52:16 +00001813ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001814{
Damien Miller95def091999-11-25 00:26:21 +11001815 char buf[1024];
1816 va_list args;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001817 int r;
Damien Miller95def091999-11-25 00:26:21 +11001818
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001819 if ((ssh->compat & SSH_BUG_DEBUG))
Ben Lindstroma14ee472000-12-07 01:24:58 +00001820 return;
1821
Damien Miller95def091999-11-25 00:26:21 +11001822 va_start(args, fmt);
1823 vsnprintf(buf, sizeof(buf), fmt, args);
1824 va_end(args);
1825
djm@openbsd.orgeb80e262017-10-13 21:13:54 +00001826 debug3("sending debug message: %s", buf);
1827
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001828 if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1829 (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1830 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1831 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1832 (r = sshpkt_send(ssh)) != 0 ||
1833 (r = ssh_packet_write_wait(ssh)) != 0)
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001834 fatal("%s: %s", __func__, ssh_err(r));
1835}
1836
dtucker@openbsd.org48c23a32017-12-10 05:55:29 +00001837void
1838sshpkt_fmt_connection_id(struct ssh *ssh, char *s, size_t l)
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001839{
1840 snprintf(s, l, "%.200s%s%s port %d",
1841 ssh->log_preamble ? ssh->log_preamble : "",
1842 ssh->log_preamble ? " " : "",
1843 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1844}
1845
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001846/*
1847 * Pretty-print connection-terminating errors and exit.
1848 */
djm@openbsd.orgad60b112019-01-19 21:33:13 +00001849static void
1850sshpkt_vfatal(struct ssh *ssh, int r, const char *fmt, va_list ap)
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001851{
djm@openbsd.orgad60b112019-01-19 21:33:13 +00001852 char *tag = NULL, remote_id[512];
djm@openbsd.orgdce74ea2020-01-30 07:20:05 +00001853 int oerrno = errno;
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001854
dtucker@openbsd.org48c23a32017-12-10 05:55:29 +00001855 sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001856
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001857 switch (r) {
1858 case SSH_ERR_CONN_CLOSED:
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +00001859 ssh_packet_clear_keys(ssh);
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001860 logdie("Connection closed by %s", remote_id);
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001861 case SSH_ERR_CONN_TIMEOUT:
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +00001862 ssh_packet_clear_keys(ssh);
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001863 logdie("Connection %s %s timed out",
1864 ssh->state->server_side ? "from" : "to", remote_id);
djm@openbsd.org639d6bc2015-05-01 07:10:01 +00001865 case SSH_ERR_DISCONNECTED:
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +00001866 ssh_packet_clear_keys(ssh);
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001867 logdie("Disconnected from %s", remote_id);
djm@openbsd.org639d6bc2015-05-01 07:10:01 +00001868 case SSH_ERR_SYSTEM_ERROR:
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +00001869 if (errno == ECONNRESET) {
1870 ssh_packet_clear_keys(ssh);
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001871 logdie("Connection reset by %s", remote_id);
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +00001872 }
djm@openbsd.org639d6bc2015-05-01 07:10:01 +00001873 /* FALLTHROUGH */
djm@openbsd.orgf3199122015-07-29 04:43:06 +00001874 case SSH_ERR_NO_CIPHER_ALG_MATCH:
1875 case SSH_ERR_NO_MAC_ALG_MATCH:
1876 case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1877 case SSH_ERR_NO_KEX_ALG_MATCH:
1878 case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1879 if (ssh && ssh->kex && ssh->kex->failed_choice) {
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +00001880 ssh_packet_clear_keys(ssh);
djm@openbsd.orgdce74ea2020-01-30 07:20:05 +00001881 errno = oerrno;
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001882 logdie("Unable to negotiate with %s: %s. "
1883 "Their offer: %s", remote_id, ssh_err(r),
djm@openbsd.orga4b9e0f2015-12-11 03:24:25 +00001884 ssh->kex->failed_choice);
djm@openbsd.orgf3199122015-07-29 04:43:06 +00001885 }
1886 /* FALLTHROUGH */
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001887 default:
djm@openbsd.orgad60b112019-01-19 21:33:13 +00001888 if (vasprintf(&tag, fmt, ap) == -1) {
1889 ssh_packet_clear_keys(ssh);
1890 logdie("%s: could not allocate failure message",
1891 __func__);
1892 }
markus@openbsd.org1e0cdf82017-05-31 08:09:45 +00001893 ssh_packet_clear_keys(ssh);
djm@openbsd.orgdce74ea2020-01-30 07:20:05 +00001894 errno = oerrno;
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001895 logdie("%s%sConnection %s %s: %s",
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001896 tag != NULL ? tag : "", tag != NULL ? ": " : "",
djm@openbsd.orga4b9e0f2015-12-11 03:24:25 +00001897 ssh->state->server_side ? "from" : "to",
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001898 remote_id, ssh_err(r));
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001899 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001900}
1901
djm@openbsd.orgad60b112019-01-19 21:33:13 +00001902void
1903sshpkt_fatal(struct ssh *ssh, int r, const char *fmt, ...)
1904{
1905 va_list ap;
1906
1907 va_start(ap, fmt);
1908 sshpkt_vfatal(ssh, r, fmt, ap);
1909 /* NOTREACHED */
1910 va_end(ap);
1911 logdie("%s: should have exited", __func__);
1912}
1913
Damien Miller5428f641999-11-25 11:54:57 +11001914/*
1915 * Logs the error plus constructs and sends a disconnect packet, closes the
1916 * connection, and exits. This function never returns. The error message
1917 * should not contain a newline. The length of the formatted message must
1918 * not exceed 1024 bytes.
1919 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001920void
markus@openbsd.org091c3022015-01-19 19:52:16 +00001921ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001922{
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001923 char buf[1024], remote_id[512];
Damien Miller95def091999-11-25 00:26:21 +11001924 va_list args;
1925 static int disconnecting = 0;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001926 int r;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +00001927
Damien Miller95def091999-11-25 00:26:21 +11001928 if (disconnecting) /* Guard against recursive invocations. */
1929 fatal("packet_disconnect called recursively.");
1930 disconnecting = 1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001931
Damien Miller5428f641999-11-25 11:54:57 +11001932 /*
1933 * Format the message. Note that the caller must make sure the
1934 * message is of limited size.
1935 */
dtucker@openbsd.org48c23a32017-12-10 05:55:29 +00001936 sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
Damien Miller95def091999-11-25 00:26:21 +11001937 va_start(args, fmt);
1938 vsnprintf(buf, sizeof(buf), fmt, args);
1939 va_end(args);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001940
Ben Lindstrom9bda7ae2002-11-09 15:46:24 +00001941 /* Display the error locally */
djm@openbsd.org07edd7e2017-02-03 23:03:33 +00001942 logit("Disconnecting %s: %.100s", remote_id, buf);
Ben Lindstrom9bda7ae2002-11-09 15:46:24 +00001943
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001944 /*
1945 * Send the disconnect message to the other side, and wait
1946 * for it to get sent.
1947 */
1948 if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
djm@openbsd.orgad60b112019-01-19 21:33:13 +00001949 sshpkt_fatal(ssh, r, "%s", __func__);
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001950
1951 if ((r = ssh_packet_write_wait(ssh)) != 0)
djm@openbsd.orgad60b112019-01-19 21:33:13 +00001952 sshpkt_fatal(ssh, r, "%s", __func__);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001953
Damien Miller95def091999-11-25 00:26:21 +11001954 /* Close the connection. */
markus@openbsd.org091c3022015-01-19 19:52:16 +00001955 ssh_packet_close(ssh);
Darren Tucker3e33cec2003-10-02 16:12:36 +10001956 cleanup_exit(255);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001957}
1958
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001959/*
1960 * Checks if there is any buffered output, and tries to write some of
1961 * the output.
1962 */
1963int
markus@openbsd.org091c3022015-01-19 19:52:16 +00001964ssh_packet_write_poll(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001965{
markus@openbsd.org091c3022015-01-19 19:52:16 +00001966 struct session_state *state = ssh->state;
1967 int len = sshbuf_len(state->output);
markus@openbsd.orga3068632016-01-14 16:17:39 +00001968 int r;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +00001969
Damien Miller95def091999-11-25 00:26:21 +11001970 if (len > 0) {
markus@openbsd.orga3068632016-01-14 16:17:39 +00001971 len = write(state->connection_out,
1972 sshbuf_ptr(state->output), len);
Damien Millerd874fa52008-07-05 09:40:56 +10001973 if (len == -1) {
Damien Millerea437422009-10-02 11:49:03 +10001974 if (errno == EINTR || errno == EAGAIN ||
1975 errno == EWOULDBLOCK)
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001976 return 0;
1977 return SSH_ERR_SYSTEM_ERROR;
Damien Miller95def091999-11-25 00:26:21 +11001978 }
markus@openbsd.orga3068632016-01-14 16:17:39 +00001979 if (len == 0)
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001980 return SSH_ERR_CONN_CLOSED;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001981 if ((r = sshbuf_consume(state->output, len)) != 0)
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001982 return r;
Damien Miller95def091999-11-25 00:26:21 +11001983 }
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001984 return 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001985}
1986
Damien Miller5428f641999-11-25 11:54:57 +11001987/*
1988 * Calls packet_write_poll repeatedly until all pending output data has been
1989 * written.
1990 */
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001991int
markus@openbsd.org091c3022015-01-19 19:52:16 +00001992ssh_packet_write_wait(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001993{
Ben Lindstromcb978aa2001-03-05 07:07:49 +00001994 fd_set *setp;
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00001995 int ret, r, ms_remain = 0;
Darren Tucker3fc464e2008-06-13 06:42:45 +10001996 struct timeval start, timeout, *timeoutp = NULL;
markus@openbsd.org091c3022015-01-19 19:52:16 +00001997 struct session_state *state = ssh->state;
Ben Lindstromcb978aa2001-03-05 07:07:49 +00001998
deraadt@openbsd.orgce445b02015-08-20 22:32:42 +00001999 setp = calloc(howmany(state->connection_out + 1,
Darren Tuckerf7288d72009-06-21 18:12:20 +10002000 NFDBITS), sizeof(fd_mask));
markus@openbsd.org091c3022015-01-19 19:52:16 +00002001 if (setp == NULL)
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00002002 return SSH_ERR_ALLOC_FAIL;
gsoares@openbsd.org66d2e222015-10-21 11:33:03 +00002003 if ((r = ssh_packet_write_poll(ssh)) != 0) {
2004 free(setp);
djm@openbsd.org84082182015-09-21 04:31:00 +00002005 return r;
gsoares@openbsd.org66d2e222015-10-21 11:33:03 +00002006 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00002007 while (ssh_packet_have_data_to_write(ssh)) {
2008 memset(setp, 0, howmany(state->connection_out + 1,
Darren Tuckerf7288d72009-06-21 18:12:20 +10002009 NFDBITS) * sizeof(fd_mask));
markus@openbsd.org091c3022015-01-19 19:52:16 +00002010 FD_SET(state->connection_out, setp);
Darren Tucker3fc464e2008-06-13 06:42:45 +10002011
markus@openbsd.org091c3022015-01-19 19:52:16 +00002012 if (state->packet_timeout_ms > 0) {
2013 ms_remain = state->packet_timeout_ms;
Darren Tucker3fc464e2008-06-13 06:42:45 +10002014 timeoutp = &timeout;
2015 }
2016 for (;;) {
markus@openbsd.org091c3022015-01-19 19:52:16 +00002017 if (state->packet_timeout_ms != -1) {
Darren Tucker3fc464e2008-06-13 06:42:45 +10002018 ms_to_timeval(&timeout, ms_remain);
dtucker@openbsd.org@openbsd.org5db6fbf2017-11-25 06:46:22 +00002019 monotime_tv(&start);
Darren Tucker3fc464e2008-06-13 06:42:45 +10002020 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00002021 if ((ret = select(state->connection_out + 1,
Darren Tuckerf7288d72009-06-21 18:12:20 +10002022 NULL, setp, NULL, timeoutp)) >= 0)
Darren Tucker3fc464e2008-06-13 06:42:45 +10002023 break;
Damien Millerea437422009-10-02 11:49:03 +10002024 if (errno != EAGAIN && errno != EINTR &&
2025 errno != EWOULDBLOCK)
Darren Tucker3fc464e2008-06-13 06:42:45 +10002026 break;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002027 if (state->packet_timeout_ms == -1)
Darren Tucker3fc464e2008-06-13 06:42:45 +10002028 continue;
2029 ms_subtract_diff(&start, &ms_remain);
2030 if (ms_remain <= 0) {
2031 ret = 0;
2032 break;
2033 }
2034 }
2035 if (ret == 0) {
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00002036 free(setp);
2037 return SSH_ERR_CONN_TIMEOUT;
Darren Tucker3fc464e2008-06-13 06:42:45 +10002038 }
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00002039 if ((r = ssh_packet_write_poll(ssh)) != 0) {
2040 free(setp);
2041 return r;
2042 }
Damien Miller95def091999-11-25 00:26:21 +11002043 }
Darren Tuckera627d422013-06-02 07:31:17 +10002044 free(setp);
djm@openbsd.org4509b5d2015-01-30 01:13:33 +00002045 return 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002046}
2047
2048/* Returns true if there is buffered data to write to the connection. */
2049
2050int
markus@openbsd.org091c3022015-01-19 19:52:16 +00002051ssh_packet_have_data_to_write(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002052{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002053 return sshbuf_len(ssh->state->output) != 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002054}
2055
2056/* Returns true if there is not too much data to write to the connection. */
2057
2058int
markus@openbsd.org091c3022015-01-19 19:52:16 +00002059ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002060{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002061 if (ssh->state->interactive_mode)
2062 return sshbuf_len(ssh->state->output) < 16384;
Damien Miller95def091999-11-25 00:26:21 +11002063 else
markus@openbsd.org091c3022015-01-19 19:52:16 +00002064 return sshbuf_len(ssh->state->output) < 128 * 1024;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002065}
2066
markus@openbsd.org091c3022015-01-19 19:52:16 +00002067void
2068ssh_packet_set_tos(struct ssh *ssh, int tos)
Ben Lindstroma7433982002-12-23 02:41:41 +00002069{
Damien Millerd2ac5d72011-05-15 08:43:13 +10002070#ifndef IP_TOS_IS_BROKEN
djm@openbsd.org51676ec2017-07-23 23:37:02 +00002071 if (!ssh_packet_connection_is_on_socket(ssh) || tos == INT_MAX)
Ben Lindstroma7433982002-12-23 02:41:41 +00002072 return;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002073 switch (ssh_packet_connection_af(ssh)) {
Damien Millerd2ac5d72011-05-15 08:43:13 +10002074# ifdef IP_TOS
2075 case AF_INET:
2076 debug3("%s: set IP_TOS 0x%02x", __func__, tos);
markus@openbsd.org091c3022015-01-19 19:52:16 +00002077 if (setsockopt(ssh->state->connection_in,
deraadt@openbsd.org4d28fa72019-06-28 13:35:04 +00002078 IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) == -1)
Damien Millerd2ac5d72011-05-15 08:43:13 +10002079 error("setsockopt IP_TOS %d: %.100s:",
2080 tos, strerror(errno));
2081 break;
2082# endif /* IP_TOS */
2083# ifdef IPV6_TCLASS
2084 case AF_INET6:
2085 debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
markus@openbsd.org091c3022015-01-19 19:52:16 +00002086 if (setsockopt(ssh->state->connection_in,
deraadt@openbsd.org4d28fa72019-06-28 13:35:04 +00002087 IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) == -1)
Damien Millerd2ac5d72011-05-15 08:43:13 +10002088 error("setsockopt IPV6_TCLASS %d: %.100s:",
2089 tos, strerror(errno));
2090 break;
Damien Millerd2ac5d72011-05-15 08:43:13 +10002091# endif /* IPV6_TCLASS */
Damien Miller23f425b2011-05-15 08:58:15 +10002092 }
Damien Millerd2ac5d72011-05-15 08:43:13 +10002093#endif /* IP_TOS_IS_BROKEN */
Damien Miller5924ceb2003-11-22 15:02:42 +11002094}
Ben Lindstroma7433982002-12-23 02:41:41 +00002095
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002096/* Informs that the current session is interactive. Sets IP flags for that. */
2097
2098void
markus@openbsd.org091c3022015-01-19 19:52:16 +00002099ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002100{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002101 struct session_state *state = ssh->state;
2102
2103 if (state->set_interactive_called)
Ben Lindstrombf555ba2001-01-18 02:04:35 +00002104 return;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002105 state->set_interactive_called = 1;
Ben Lindstrombf555ba2001-01-18 02:04:35 +00002106
Damien Miller95def091999-11-25 00:26:21 +11002107 /* Record that we are in interactive mode. */
markus@openbsd.org091c3022015-01-19 19:52:16 +00002108 state->interactive_mode = interactive;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002109
Damien Miller34132e52000-01-14 15:45:46 +11002110 /* Only set socket options if using a socket. */
markus@openbsd.org091c3022015-01-19 19:52:16 +00002111 if (!ssh_packet_connection_is_on_socket(ssh))
Ben Lindstrom93b6b772003-04-27 17:55:33 +00002112 return;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002113 set_nodelay(state->connection_in);
2114 ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2115 qos_bulk);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002116}
2117
2118/* Returns true if the current connection is interactive. */
2119
2120int
markus@openbsd.org091c3022015-01-19 19:52:16 +00002121ssh_packet_is_interactive(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002122{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002123 return ssh->state->interactive_mode;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002124}
Damien Miller6162d121999-11-21 13:23:52 +11002125
Darren Tucker1f8311c2004-05-13 16:39:33 +10002126int
markus@openbsd.org091c3022015-01-19 19:52:16 +00002127ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
Damien Miller6162d121999-11-21 13:23:52 +11002128{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002129 struct session_state *state = ssh->state;
2130
2131 if (state->set_maxsize_called) {
Damien Miller996acd22003-04-09 20:59:48 +10002132 logit("packet_set_maxsize: called twice: old %d new %d",
markus@openbsd.org091c3022015-01-19 19:52:16 +00002133 state->max_packet_size, s);
Damien Miller95def091999-11-25 00:26:21 +11002134 return -1;
2135 }
2136 if (s < 4 * 1024 || s > 1024 * 1024) {
Damien Miller996acd22003-04-09 20:59:48 +10002137 logit("packet_set_maxsize: bad size %d", s);
Damien Miller95def091999-11-25 00:26:21 +11002138 return -1;
2139 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00002140 state->set_maxsize_called = 1;
Ben Lindstrom16d45b32001-06-13 04:39:18 +00002141 debug("packet_set_maxsize: setting to %d", s);
markus@openbsd.org091c3022015-01-19 19:52:16 +00002142 state->max_packet_size = s;
Damien Miller95def091999-11-25 00:26:21 +11002143 return s;
Damien Miller6162d121999-11-21 13:23:52 +11002144}
Ben Lindstrom5699c5f2001-03-05 06:17:49 +00002145
Darren Tuckerf7288d72009-06-21 18:12:20 +10002146int
markus@openbsd.org091c3022015-01-19 19:52:16 +00002147ssh_packet_inc_alive_timeouts(struct ssh *ssh)
Darren Tuckerf7288d72009-06-21 18:12:20 +10002148{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002149 return ++ssh->state->keep_alive_timeouts;
Darren Tuckerf7288d72009-06-21 18:12:20 +10002150}
2151
2152void
markus@openbsd.org091c3022015-01-19 19:52:16 +00002153ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
Darren Tuckerf7288d72009-06-21 18:12:20 +10002154{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002155 ssh->state->keep_alive_timeouts = ka;
Darren Tuckerf7288d72009-06-21 18:12:20 +10002156}
2157
2158u_int
markus@openbsd.org091c3022015-01-19 19:52:16 +00002159ssh_packet_get_maxsize(struct ssh *ssh)
Darren Tuckerf7288d72009-06-21 18:12:20 +10002160{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002161 return ssh->state->max_packet_size;
Damien Miller9f643902001-11-12 11:02:52 +11002162}
2163
Damien Millera5539d22003-04-09 20:50:06 +10002164void
dtucker@openbsd.orgc998bf02017-02-03 02:56:00 +00002165ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, u_int32_t seconds)
Damien Millera5539d22003-04-09 20:50:06 +10002166{
dtucker@openbsd.orgc998bf02017-02-03 02:56:00 +00002167 debug3("rekey after %llu bytes, %u seconds", (unsigned long long)bytes,
2168 (unsigned int)seconds);
markus@openbsd.org091c3022015-01-19 19:52:16 +00002169 ssh->state->rekey_limit = bytes;
2170 ssh->state->rekey_interval = seconds;
Darren Tuckerc53c2af2013-05-16 20:28:16 +10002171}
2172
2173time_t
markus@openbsd.org091c3022015-01-19 19:52:16 +00002174ssh_packet_get_rekey_timeout(struct ssh *ssh)
Darren Tuckerc53c2af2013-05-16 20:28:16 +10002175{
2176 time_t seconds;
2177
markus@openbsd.org091c3022015-01-19 19:52:16 +00002178 seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
Darren Tuckerb759c9c2013-06-02 07:46:16 +10002179 monotime();
Darren Tucker5f96f3b2013-05-16 20:29:28 +10002180 return (seconds <= 0 ? 1 : seconds);
Damien Millera5539d22003-04-09 20:50:06 +10002181}
Damien Miller9786e6e2005-07-26 21:54:56 +10002182
2183void
markus@openbsd.org091c3022015-01-19 19:52:16 +00002184ssh_packet_set_server(struct ssh *ssh)
Damien Miller9786e6e2005-07-26 21:54:56 +10002185{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002186 ssh->state->server_side = 1;
djm@openbsd.org0a843d92018-12-27 03:25:24 +00002187 ssh->kex->server = 1; /* XXX unify? */
Damien Miller9786e6e2005-07-26 21:54:56 +10002188}
2189
2190void
markus@openbsd.org091c3022015-01-19 19:52:16 +00002191ssh_packet_set_authenticated(struct ssh *ssh)
Damien Miller9786e6e2005-07-26 21:54:56 +10002192{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002193 ssh->state->after_authentication = 1;
Darren Tuckerf7288d72009-06-21 18:12:20 +10002194}
2195
2196void *
markus@openbsd.org091c3022015-01-19 19:52:16 +00002197ssh_packet_get_input(struct ssh *ssh)
Darren Tuckerf7288d72009-06-21 18:12:20 +10002198{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002199 return (void *)ssh->state->input;
Darren Tuckerf7288d72009-06-21 18:12:20 +10002200}
2201
2202void *
markus@openbsd.org091c3022015-01-19 19:52:16 +00002203ssh_packet_get_output(struct ssh *ssh)
Darren Tuckerf7288d72009-06-21 18:12:20 +10002204{
markus@openbsd.org091c3022015-01-19 19:52:16 +00002205 return (void *)ssh->state->output;
Darren Tuckerf7288d72009-06-21 18:12:20 +10002206}
2207
Damien Millerc31a0cd2014-05-15 14:37:39 +10002208/* Reset after_authentication and reset compression in post-auth privsep */
markus@openbsd.org091c3022015-01-19 19:52:16 +00002209static int
2210ssh_packet_set_postauth(struct ssh *ssh)
Damien Millerc31a0cd2014-05-15 14:37:39 +10002211{
djm@openbsd.org0082fba2016-09-28 16:33:06 +00002212 int r;
Damien Millerc31a0cd2014-05-15 14:37:39 +10002213
2214 debug("%s: called", __func__);
2215 /* This was set in net child, but is not visible in user child */
markus@openbsd.org091c3022015-01-19 19:52:16 +00002216 ssh->state->after_authentication = 1;
2217 ssh->state->rekeying = 0;
djm@openbsd.org0082fba2016-09-28 16:33:06 +00002218 if ((r = ssh_packet_enable_delayed_compress(ssh)) != 0)
2219 return r;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002220 return 0;
2221}
2222
2223/* Packet state (de-)serialization for privsep */
2224
2225/* turn kex into a blob for packet state serialization */
2226static int
2227kex_to_blob(struct sshbuf *m, struct kex *kex)
2228{
2229 int r;
2230
2231 if ((r = sshbuf_put_string(m, kex->session_id,
2232 kex->session_id_len)) != 0 ||
2233 (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
djm@openbsd.org349ecd42017-12-18 23:13:42 +00002234 (r = sshbuf_put_cstring(m, kex->hostkey_alg)) != 0 ||
markus@openbsd.org091c3022015-01-19 19:52:16 +00002235 (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
djm@openbsd.org349ecd42017-12-18 23:13:42 +00002236 (r = sshbuf_put_u32(m, kex->hostkey_nid)) != 0 ||
markus@openbsd.org091c3022015-01-19 19:52:16 +00002237 (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2238 (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2239 (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
djm@openbsd.org0a843d92018-12-27 03:25:24 +00002240 (r = sshbuf_put_stringb(m, kex->client_version)) != 0 ||
2241 (r = sshbuf_put_stringb(m, kex->server_version)) != 0 ||
2242 (r = sshbuf_put_u32(m, kex->flags)) != 0)
markus@openbsd.org091c3022015-01-19 19:52:16 +00002243 return r;
2244 return 0;
2245}
2246
2247/* turn key exchange results into a blob for packet state serialization */
2248static int
2249newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2250{
2251 struct sshbuf *b;
2252 struct sshcipher_ctx *cc;
2253 struct sshcomp *comp;
2254 struct sshenc *enc;
2255 struct sshmac *mac;
2256 struct newkeys *newkey;
2257 int r;
2258
2259 if ((newkey = ssh->state->newkeys[mode]) == NULL)
2260 return SSH_ERR_INTERNAL_ERROR;
2261 enc = &newkey->enc;
2262 mac = &newkey->mac;
2263 comp = &newkey->comp;
djm@openbsd.org4706c1d2016-08-03 05:41:57 +00002264 cc = (mode == MODE_OUT) ? ssh->state->send_context :
2265 ssh->state->receive_context;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002266 if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2267 return r;
2268 if ((b = sshbuf_new()) == NULL)
2269 return SSH_ERR_ALLOC_FAIL;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002270 if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
markus@openbsd.org091c3022015-01-19 19:52:16 +00002271 (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2272 (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2273 (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2274 (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2275 goto out;
2276 if (cipher_authlen(enc->cipher) == 0) {
2277 if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2278 (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2279 (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2280 goto out;
2281 }
2282 if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
markus@openbsd.org091c3022015-01-19 19:52:16 +00002283 (r = sshbuf_put_cstring(b, comp->name)) != 0)
2284 goto out;
2285 r = sshbuf_put_stringb(m, b);
2286 out:
mmcc@openbsd.org52d70782015-12-11 04:21:11 +00002287 sshbuf_free(b);
markus@openbsd.org091c3022015-01-19 19:52:16 +00002288 return r;
2289}
2290
2291/* serialize packet state into a blob */
2292int
2293ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2294{
2295 struct session_state *state = ssh->state;
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002296 int r;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002297
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002298 if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2299 (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2300 (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
2301 (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
2302 (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
2303 (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2304 (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2305 (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2306 (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2307 (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2308 (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2309 (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
djm@openbsd.org7461a5b2017-05-08 00:21:36 +00002310 (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0 ||
2311 (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2312 (r = sshbuf_put_stringb(m, state->output)) != 0)
djm@openbsd.org2e58a692017-05-08 06:03:39 +00002313 return r;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002314
markus@openbsd.org091c3022015-01-19 19:52:16 +00002315 return 0;
2316}
2317
2318/* restore key exchange results from blob for packet state de-serialization */
2319static int
2320newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2321{
2322 struct sshbuf *b = NULL;
2323 struct sshcomp *comp;
2324 struct sshenc *enc;
2325 struct sshmac *mac;
2326 struct newkeys *newkey = NULL;
2327 size_t keylen, ivlen, maclen;
2328 int r;
2329
2330 if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2331 r = SSH_ERR_ALLOC_FAIL;
2332 goto out;
2333 }
2334 if ((r = sshbuf_froms(m, &b)) != 0)
2335 goto out;
2336#ifdef DEBUG_PK
2337 sshbuf_dump(b, stderr);
2338#endif
2339 enc = &newkey->enc;
2340 mac = &newkey->mac;
2341 comp = &newkey->comp;
2342
2343 if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
markus@openbsd.org091c3022015-01-19 19:52:16 +00002344 (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2345 (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2346 (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2347 (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2348 goto out;
djm@openbsd.org33f86262017-06-24 06:38:11 +00002349 if ((enc->cipher = cipher_by_name(enc->name)) == NULL) {
2350 r = SSH_ERR_INVALID_FORMAT;
2351 goto out;
2352 }
markus@openbsd.org091c3022015-01-19 19:52:16 +00002353 if (cipher_authlen(enc->cipher) == 0) {
2354 if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2355 goto out;
2356 if ((r = mac_setup(mac, mac->name)) != 0)
2357 goto out;
2358 if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2359 (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2360 goto out;
2361 if (maclen > mac->key_len) {
2362 r = SSH_ERR_INVALID_FORMAT;
2363 goto out;
2364 }
2365 mac->key_len = maclen;
2366 }
2367 if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
markus@openbsd.org091c3022015-01-19 19:52:16 +00002368 (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2369 goto out;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002370 if (sshbuf_len(b) != 0) {
2371 r = SSH_ERR_INVALID_FORMAT;
2372 goto out;
2373 }
2374 enc->key_len = keylen;
2375 enc->iv_len = ivlen;
2376 ssh->kex->newkeys[mode] = newkey;
2377 newkey = NULL;
2378 r = 0;
2379 out:
mmcc@openbsd.orgd59ce082015-12-10 17:08:40 +00002380 free(newkey);
mmcc@openbsd.org52d70782015-12-11 04:21:11 +00002381 sshbuf_free(b);
markus@openbsd.org091c3022015-01-19 19:52:16 +00002382 return r;
2383}
2384
2385/* restore kex from blob for packet state de-serialization */
2386static int
2387kex_from_blob(struct sshbuf *m, struct kex **kexp)
2388{
2389 struct kex *kex;
2390 int r;
2391
djm@openbsd.org0a843d92018-12-27 03:25:24 +00002392 if ((kex = kex_new()) == NULL)
2393 return SSH_ERR_ALLOC_FAIL;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002394 if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2395 (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
djm@openbsd.org349ecd42017-12-18 23:13:42 +00002396 (r = sshbuf_get_cstring(m, &kex->hostkey_alg, NULL)) != 0 ||
markus@openbsd.org091c3022015-01-19 19:52:16 +00002397 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
djm@openbsd.org349ecd42017-12-18 23:13:42 +00002398 (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_nid)) != 0 ||
markus@openbsd.org091c3022015-01-19 19:52:16 +00002399 (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2400 (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2401 (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
djm@openbsd.org0a843d92018-12-27 03:25:24 +00002402 (r = sshbuf_get_stringb(m, kex->client_version)) != 0 ||
2403 (r = sshbuf_get_stringb(m, kex->server_version)) != 0 ||
2404 (r = sshbuf_get_u32(m, &kex->flags)) != 0)
markus@openbsd.org091c3022015-01-19 19:52:16 +00002405 goto out;
2406 kex->server = 1;
2407 kex->done = 1;
2408 r = 0;
2409 out:
2410 if (r != 0 || kexp == NULL) {
djm@openbsd.org0a843d92018-12-27 03:25:24 +00002411 kex_free(kex);
markus@openbsd.org091c3022015-01-19 19:52:16 +00002412 if (kexp != NULL)
2413 *kexp = NULL;
2414 } else {
djm@openbsd.org0a843d92018-12-27 03:25:24 +00002415 kex_free(*kexp);
markus@openbsd.org091c3022015-01-19 19:52:16 +00002416 *kexp = kex;
2417 }
2418 return r;
2419}
2420
2421/*
2422 * Restore packet state from content of blob 'm' (de-serialization).
2423 * Note that 'm' will be partially consumed on parsing or any other errors.
2424 */
2425int
2426ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2427{
2428 struct session_state *state = ssh->state;
djm@openbsd.orgacaf34f2017-05-07 23:12:57 +00002429 const u_char *input, *output;
2430 size_t ilen, olen;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002431 int r;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002432
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002433 if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2434 (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2435 (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
2436 (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
2437 (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
2438 (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2439 (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2440 (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2441 (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2442 (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2443 (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2444 (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2445 (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2446 return r;
2447 /*
2448 * We set the time here so that in post-auth privsep slave we
2449 * count from the completion of the authentication.
2450 */
2451 state->rekey_time = monotime();
2452 /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2453 if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2454 (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2455 return r;
2456
djm@openbsd.org0082fba2016-09-28 16:33:06 +00002457 if ((r = ssh_packet_set_postauth(ssh)) != 0)
markus@openbsd.org091c3022015-01-19 19:52:16 +00002458 return r;
2459
2460 sshbuf_reset(state->input);
2461 sshbuf_reset(state->output);
2462 if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2463 (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2464 (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2465 (r = sshbuf_put(state->output, output, olen)) != 0)
2466 return r;
2467
markus@openbsd.org091c3022015-01-19 19:52:16 +00002468 if (sshbuf_len(m))
2469 return SSH_ERR_INVALID_FORMAT;
2470 debug3("%s: done", __func__);
2471 return 0;
2472}
2473
2474/* NEW API */
2475
2476/* put data to the outgoing packet */
2477
2478int
2479sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2480{
2481 return sshbuf_put(ssh->state->outgoing_packet, v, len);
2482}
2483
2484int
2485sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2486{
2487 return sshbuf_putb(ssh->state->outgoing_packet, b);
2488}
2489
2490int
2491sshpkt_put_u8(struct ssh *ssh, u_char val)
2492{
2493 return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2494}
2495
2496int
2497sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2498{
2499 return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2500}
2501
2502int
2503sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2504{
2505 return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2506}
2507
2508int
2509sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2510{
2511 return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2512}
2513
2514int
2515sshpkt_put_cstring(struct ssh *ssh, const void *v)
2516{
2517 return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2518}
2519
2520int
2521sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2522{
2523 return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2524}
2525
djm@openbsd.org71e67ff2019-01-21 10:35:09 +00002526int
2527sshpkt_getb_froms(struct ssh *ssh, struct sshbuf **valp)
2528{
2529 return sshbuf_froms(ssh->state->incoming_packet, valp);
2530}
2531
djm@openbsd.org734226b2015-04-27 01:52:30 +00002532#ifdef WITH_OPENSSL
2533#ifdef OPENSSL_HAS_ECC
markus@openbsd.org091c3022015-01-19 19:52:16 +00002534int
2535sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2536{
2537 return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2538}
djm@openbsd.org734226b2015-04-27 01:52:30 +00002539#endif /* OPENSSL_HAS_ECC */
markus@openbsd.org091c3022015-01-19 19:52:16 +00002540
markus@openbsd.org091c3022015-01-19 19:52:16 +00002541
2542int
2543sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2544{
2545 return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2546}
Damien Miller773dda22015-01-30 23:10:17 +11002547#endif /* WITH_OPENSSL */
markus@openbsd.org091c3022015-01-19 19:52:16 +00002548
2549/* fetch data from the incoming packet */
2550
2551int
2552sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2553{
2554 return sshbuf_get(ssh->state->incoming_packet, valp, len);
2555}
2556
2557int
2558sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2559{
2560 return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2561}
2562
2563int
2564sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2565{
2566 return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2567}
2568
2569int
2570sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2571{
2572 return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2573}
2574
2575int
2576sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2577{
2578 return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2579}
2580
2581int
2582sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2583{
2584 return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2585}
2586
2587int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002588sshpkt_peek_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2589{
2590 return sshbuf_peek_string_direct(ssh->state->incoming_packet, valp, lenp);
2591}
2592
2593int
markus@openbsd.org091c3022015-01-19 19:52:16 +00002594sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2595{
2596 return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2597}
2598
djm@openbsd.org734226b2015-04-27 01:52:30 +00002599#ifdef WITH_OPENSSL
2600#ifdef OPENSSL_HAS_ECC
markus@openbsd.org091c3022015-01-19 19:52:16 +00002601int
2602sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2603{
2604 return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2605}
djm@openbsd.org734226b2015-04-27 01:52:30 +00002606#endif /* OPENSSL_HAS_ECC */
markus@openbsd.org091c3022015-01-19 19:52:16 +00002607
markus@openbsd.org091c3022015-01-19 19:52:16 +00002608int
djm@openbsd.org7be85722019-01-21 09:54:11 +00002609sshpkt_get_bignum2(struct ssh *ssh, BIGNUM **valp)
markus@openbsd.org091c3022015-01-19 19:52:16 +00002610{
djm@openbsd.org7be85722019-01-21 09:54:11 +00002611 return sshbuf_get_bignum2(ssh->state->incoming_packet, valp);
markus@openbsd.org091c3022015-01-19 19:52:16 +00002612}
Damien Miller773dda22015-01-30 23:10:17 +11002613#endif /* WITH_OPENSSL */
markus@openbsd.org091c3022015-01-19 19:52:16 +00002614
2615int
2616sshpkt_get_end(struct ssh *ssh)
2617{
2618 if (sshbuf_len(ssh->state->incoming_packet) > 0)
2619 return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2620 return 0;
2621}
2622
2623const u_char *
2624sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2625{
2626 if (lenp != NULL)
2627 *lenp = sshbuf_len(ssh->state->incoming_packet);
2628 return sshbuf_ptr(ssh->state->incoming_packet);
2629}
2630
2631/* start a new packet */
2632
2633int
2634sshpkt_start(struct ssh *ssh, u_char type)
2635{
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002636 u_char buf[6]; /* u32 packet length, u8 pad len, u8 type */
markus@openbsd.org091c3022015-01-19 19:52:16 +00002637
2638 DBG(debug("packet_start[%d]", type));
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002639 memset(buf, 0, sizeof(buf));
2640 buf[sizeof(buf) - 1] = type;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002641 sshbuf_reset(ssh->state->outgoing_packet);
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002642 return sshbuf_put(ssh->state->outgoing_packet, buf, sizeof(buf));
markus@openbsd.org091c3022015-01-19 19:52:16 +00002643}
2644
markus@openbsd.org8d057842016-09-30 09:19:13 +00002645static int
2646ssh_packet_send_mux(struct ssh *ssh)
2647{
2648 struct session_state *state = ssh->state;
2649 u_char type, *cp;
2650 size_t len;
2651 int r;
2652
2653 if (ssh->kex)
2654 return SSH_ERR_INTERNAL_ERROR;
2655 len = sshbuf_len(state->outgoing_packet);
2656 if (len < 6)
2657 return SSH_ERR_INTERNAL_ERROR;
2658 cp = sshbuf_mutable_ptr(state->outgoing_packet);
2659 type = cp[5];
2660 if (ssh_packet_log_type(type))
2661 debug3("%s: type %u", __func__, type);
2662 /* drop everything, but the connection protocol */
2663 if (type >= SSH2_MSG_CONNECTION_MIN &&
2664 type <= SSH2_MSG_CONNECTION_MAX) {
2665 POKE_U32(cp, len - 4);
2666 if ((r = sshbuf_putb(state->output,
2667 state->outgoing_packet)) != 0)
2668 return r;
2669 /* sshbuf_dump(state->output, stderr); */
2670 }
2671 sshbuf_reset(state->outgoing_packet);
2672 return 0;
2673}
2674
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002675/*
2676 * 9.2. Ignored Data Message
2677 *
2678 * byte SSH_MSG_IGNORE
2679 * string data
2680 *
2681 * All implementations MUST understand (and ignore) this message at any
2682 * time (after receiving the protocol version). No implementation is
2683 * required to send them. This message can be used as an additional
2684 * protection measure against advanced traffic analysis techniques.
2685 */
2686int
2687sshpkt_msg_ignore(struct ssh *ssh, u_int nbytes)
2688{
2689 u_int32_t rnd = 0;
2690 int r;
2691 u_int i;
2692
2693 if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
2694 (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2695 return r;
2696 for (i = 0; i < nbytes; i++) {
2697 if (i % 4 == 0)
2698 rnd = arc4random();
2699 if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2700 return r;
2701 rnd >>= 8;
2702 }
2703 return 0;
2704}
2705
markus@openbsd.org091c3022015-01-19 19:52:16 +00002706/* send it */
2707
2708int
2709sshpkt_send(struct ssh *ssh)
2710{
markus@openbsd.org8d057842016-09-30 09:19:13 +00002711 if (ssh->state && ssh->state->mux)
2712 return ssh_packet_send_mux(ssh);
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002713 return ssh_packet_send2(ssh);
markus@openbsd.org091c3022015-01-19 19:52:16 +00002714}
2715
2716int
2717sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2718{
2719 char buf[1024];
2720 va_list args;
2721 int r;
2722
2723 va_start(args, fmt);
2724 vsnprintf(buf, sizeof(buf), fmt, args);
2725 va_end(args);
2726
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002727 if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2728 (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2729 (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2730 (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2731 (r = sshpkt_send(ssh)) != 0)
2732 return r;
markus@openbsd.org091c3022015-01-19 19:52:16 +00002733 return 0;
2734}
2735
2736/* roundup current message to pad bytes */
2737int
2738sshpkt_add_padding(struct ssh *ssh, u_char pad)
2739{
2740 ssh->state->extra_pad = pad;
2741 return 0;
Damien Millerc31a0cd2014-05-15 14:37:39 +10002742}