Annotation of src/usr.bin/ssh/packet.c, Revision 1.221
1.221 ! mmcc 1: /* $OpenBSD: packet.c,v 1.220 2015/12/11 03:24:25 djm Exp $ */
1.1 deraadt 2: /*
1.15 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.35 deraadt 6: * This file contains code implementing the packet protocol and communication
7: * with the other side. This same code is used both on client and server side.
1.29 markus 8: *
1.35 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
1.29 markus 14: *
1.25 markus 15: *
16: * SSH2 packet format added by Markus Friedl.
1.69 markus 17: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.25 markus 18: *
1.35 deraadt 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.
1.15 deraadt 38: */
1.1 deraadt 39:
1.203 deraadt 40: #include <sys/param.h> /* MIN roundup */
1.142 deraadt 41: #include <sys/types.h>
1.105 markus 42: #include <sys/queue.h>
1.132 stevesk 43: #include <sys/socket.h>
1.138 stevesk 44: #include <sys/time.h>
1.132 stevesk 45: #include <netinet/in.h>
1.121 stevesk 46: #include <netinet/ip.h>
1.134 stevesk 47:
1.135 stevesk 48: #include <errno.h>
1.134 stevesk 49: #include <stdarg.h>
1.141 stevesk 50: #include <stdio.h>
1.140 stevesk 51: #include <stdlib.h>
1.137 stevesk 52: #include <string.h>
1.136 stevesk 53: #include <unistd.h>
1.203 deraadt 54: #include <limits.h>
1.142 deraadt 55: #include <signal.h>
1.184 dtucker 56: #include <time.h>
1.1 deraadt 57:
1.201 markus 58: #include <zlib.h>
59:
60: #include "buffer.h" /* typedefs XXX */
61: #include "key.h" /* typedefs XXX */
62:
1.1 deraadt 63: #include "xmalloc.h"
64: #include "crc32.h"
1.9 dugsong 65: #include "deattack.h"
1.25 markus 66: #include "compat.h"
1.45 markus 67: #include "ssh1.h"
1.25 markus 68: #include "ssh2.h"
1.37 markus 69: #include "cipher.h"
1.201 markus 70: #include "sshkey.h"
1.25 markus 71: #include "kex.h"
1.200 markus 72: #include "digest.h"
1.50 markus 73: #include "mac.h"
1.46 markus 74: #include "log.h"
75: #include "canohost.h"
1.87 stevesk 76: #include "misc.h"
1.198 millert 77: #include "channels.h"
1.95 markus 78: #include "ssh.h"
1.201 markus 79: #include "packet.h"
80: #include "roaming.h"
1.197 djm 81: #include "ssherr.h"
1.201 markus 82: #include "sshbuf.h"
1.25 markus 83:
84: #ifdef PACKET_DEBUG
85: #define DBG(x) x
86: #else
87: #define DBG(x)
88: #endif
89:
1.159 markus 90: #define PACKET_MAX_SIZE (256 * 1024)
91:
1.161 andreas 92: struct packet_state {
93: u_int32_t seqnr;
94: u_int32_t packets;
95: u_int64_t blocks;
96: u_int64_t bytes;
97: };
98:
99: struct packet {
100: TAILQ_ENTRY(packet) next;
101: u_char type;
1.201 markus 102: struct sshbuf *payload;
1.161 andreas 103: };
104:
105: struct session_state {
106: /*
107: * This variable contains the file descriptors used for
108: * communicating with the other side. connection_in is used for
109: * reading; connection_out for writing. These can be the same
110: * descriptor, in which case it is assumed to be a socket.
111: */
112: int connection_in;
113: int connection_out;
114:
115: /* Protocol flags for the remote side. */
116: u_int remote_protocol_flags;
1.1 deraadt 117:
1.161 andreas 118: /* Encryption context for receiving data. Only used for decryption. */
1.201 markus 119: struct sshcipher_ctx receive_context;
1.1 deraadt 120:
1.161 andreas 121: /* Encryption context for sending data. Only used for encryption. */
1.201 markus 122: struct sshcipher_ctx send_context;
1.14 markus 123:
1.161 andreas 124: /* Buffer for raw input data from the socket. */
1.201 markus 125: struct sshbuf *input;
1.1 deraadt 126:
1.161 andreas 127: /* Buffer for raw output data going to the socket. */
1.201 markus 128: struct sshbuf *output;
1.1 deraadt 129:
1.161 andreas 130: /* Buffer for the partial outgoing packet being constructed. */
1.201 markus 131: struct sshbuf *outgoing_packet;
1.1 deraadt 132:
1.161 andreas 133: /* Buffer for the incoming packet currently being processed. */
1.201 markus 134: struct sshbuf *incoming_packet;
1.1 deraadt 135:
1.161 andreas 136: /* Scratch buffer for packet compression/decompression. */
1.201 markus 137: struct sshbuf *compression_buffer;
138:
139: /* Incoming/outgoing compression dictionaries */
140: z_stream compression_in_stream;
141: z_stream compression_out_stream;
142: int compression_in_started;
143: int compression_out_started;
144: int compression_in_failures;
145: int compression_out_failures;
1.1 deraadt 146:
1.161 andreas 147: /*
148: * Flag indicating whether packet compression/decompression is
149: * enabled.
150: */
151: int packet_compression;
1.1 deraadt 152:
1.161 andreas 153: /* default maximum packet size */
154: u_int max_packet_size;
1.1 deraadt 155:
1.161 andreas 156: /* Flag indicating whether this module has been initialized. */
157: int initialized;
1.12 markus 158:
1.161 andreas 159: /* Set to true if the connection is interactive. */
160: int interactive_mode;
1.1 deraadt 161:
1.161 andreas 162: /* Set to true if we are the server side. */
163: int server_side;
1.1 deraadt 164:
1.161 andreas 165: /* Set to true if we are authenticated. */
166: int after_authentication;
1.118 markus 167:
1.161 andreas 168: int keep_alive_timeouts;
1.118 markus 169:
1.161 andreas 170: /* The maximum time that we will wait to send or receive a packet */
171: int packet_timeout_ms;
1.151 dtucker 172:
1.161 andreas 173: /* Session key information for Encryption and MAC */
1.201 markus 174: struct newkeys *newkeys[MODE_MAX];
1.161 andreas 175: struct packet_state p_read, p_send;
1.154 dtucker 176:
1.184 dtucker 177: /* Volume-based rekeying */
1.161 andreas 178: u_int64_t max_blocks_in, max_blocks_out;
179: u_int32_t rekey_limit;
1.105 markus 180:
1.184 dtucker 181: /* Time-based rekeying */
1.208 markus 182: u_int32_t rekey_interval; /* how often in seconds */
1.184 dtucker 183: time_t rekey_time; /* time of last rekeying */
184:
1.161 andreas 185: /* Session key for protocol v1 */
186: u_char ssh1_key[SSH_SESSION_KEY_LENGTH];
187: u_int ssh1_keylen;
1.25 markus 188:
1.161 andreas 189: /* roundup current message to extra_pad bytes */
190: u_char extra_pad;
1.95 markus 191:
1.161 andreas 192: /* XXX discard incoming data after MAC error */
193: u_int packet_discard;
1.201 markus 194: struct sshmac *packet_discard_mac;
1.71 markus 195:
1.161 andreas 196: /* Used in packet_read_poll2() */
197: u_int packlen;
1.159 markus 198:
1.165 andreas 199: /* Used in packet_send2 */
200: int rekeying;
201:
202: /* Used in packet_set_interactive */
203: int set_interactive_called;
204:
205: /* Used in packet_set_maxsize */
206: int set_maxsize_called;
207:
1.201 markus 208: /* One-off warning about weak ciphers */
209: int cipher_warning_done;
210:
211: /* SSH1 CRC compensation attack detector */
212: struct deattack_ctx deattack;
213:
1.161 andreas 214: TAILQ_HEAD(, packet) outgoing;
1.105 markus 215: };
1.161 andreas 216:
1.201 markus 217: struct ssh *
218: ssh_alloc_session_state(void)
1.161 andreas 219: {
1.201 markus 220: struct ssh *ssh = NULL;
221: struct session_state *state = NULL;
1.161 andreas 222:
1.201 markus 223: if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
224: (state = calloc(1, sizeof(*state))) == NULL ||
225: (state->input = sshbuf_new()) == NULL ||
226: (state->output = sshbuf_new()) == NULL ||
227: (state->outgoing_packet = sshbuf_new()) == NULL ||
228: (state->incoming_packet = sshbuf_new()) == NULL)
229: goto fail;
230: TAILQ_INIT(&state->outgoing);
1.202 markus 231: TAILQ_INIT(&ssh->private_keys);
232: TAILQ_INIT(&ssh->public_keys);
1.201 markus 233: state->connection_in = -1;
234: state->connection_out = -1;
235: state->max_packet_size = 32768;
236: state->packet_timeout_ms = -1;
237: state->p_send.packets = state->p_read.packets = 0;
238: state->initialized = 1;
239: /*
240: * ssh_packet_send2() needs to queue packets until
241: * we've done the initial key exchange.
242: */
243: state->rekeying = 1;
244: ssh->state = state;
245: return ssh;
246: fail:
247: if (state) {
248: sshbuf_free(state->input);
249: sshbuf_free(state->output);
250: sshbuf_free(state->incoming_packet);
251: sshbuf_free(state->outgoing_packet);
252: free(state);
253: }
254: free(ssh);
255: return NULL;
1.161 andreas 256: }
1.105 markus 257:
1.16 markus 258: /*
259: * Sets the descriptors used for communication. Disables encryption until
260: * packet_set_encryption_key is called.
261: */
1.201 markus 262: struct ssh *
263: ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
1.1 deraadt 264: {
1.201 markus 265: struct session_state *state;
266: const struct sshcipher *none = cipher_by_name("none");
1.197 djm 267: int r;
1.97 deraadt 268:
1.205 djm 269: if (none == NULL) {
270: error("%s: cannot load cipher 'none'", __func__);
271: return NULL;
272: }
1.201 markus 273: if (ssh == NULL)
274: ssh = ssh_alloc_session_state();
1.205 djm 275: if (ssh == NULL) {
276: error("%s: cound not allocate state", __func__);
277: return NULL;
278: }
1.201 markus 279: state = ssh->state;
280: state->connection_in = fd_in;
281: state->connection_out = fd_out;
282: if ((r = cipher_init(&state->send_context, none,
1.197 djm 283: (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
1.201 markus 284: (r = cipher_init(&state->receive_context, none,
1.205 djm 285: (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
286: error("%s: cipher_init failed: %s", __func__, ssh_err(r));
1.209 jsg 287: free(ssh);
1.205 djm 288: return NULL;
289: }
1.201 markus 290: state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
291: deattack_init(&state->deattack);
1.207 djm 292: /*
293: * Cache the IP address of the remote connection for use in error
294: * messages that might be generated after the connection has closed.
295: */
296: (void)ssh_remote_ipaddr(ssh);
1.201 markus 297: return ssh;
1.1 deraadt 298: }
299:
1.154 dtucker 300: void
1.201 markus 301: ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
1.154 dtucker 302: {
1.201 markus 303: struct session_state *state = ssh->state;
304:
1.174 djm 305: if (timeout <= 0 || count <= 0) {
1.201 markus 306: state->packet_timeout_ms = -1;
1.154 dtucker 307: return;
308: }
309: if ((INT_MAX / 1000) / count < timeout)
1.201 markus 310: state->packet_timeout_ms = INT_MAX;
1.154 dtucker 311: else
1.201 markus 312: state->packet_timeout_ms = timeout * count * 1000;
1.154 dtucker 313: }
314:
1.201 markus 315: int
316: ssh_packet_stop_discard(struct ssh *ssh)
1.159 markus 317: {
1.201 markus 318: struct session_state *state = ssh->state;
319: int r;
320:
321: if (state->packet_discard_mac) {
1.159 markus 322: char buf[1024];
1.201 markus 323:
1.159 markus 324: memset(buf, 'a', sizeof(buf));
1.201 markus 325: while (sshbuf_len(state->incoming_packet) <
1.161 andreas 326: PACKET_MAX_SIZE)
1.201 markus 327: if ((r = sshbuf_put(state->incoming_packet, buf,
328: sizeof(buf))) != 0)
329: return r;
330: (void) mac_compute(state->packet_discard_mac,
331: state->p_read.seqnr,
332: sshbuf_ptr(state->incoming_packet), PACKET_MAX_SIZE,
333: NULL, 0);
1.159 markus 334: }
1.220 djm 335: logit("Finished discarding for %.200s port %d",
336: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.201 markus 337: return SSH_ERR_MAC_INVALID;
1.159 markus 338: }
339:
1.201 markus 340: static int
341: ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
342: struct sshmac *mac, u_int packet_length, u_int discard)
1.159 markus 343: {
1.201 markus 344: struct session_state *state = ssh->state;
345: int r;
346:
347: if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
348: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
349: return r;
350: return SSH_ERR_MAC_INVALID;
351: }
1.159 markus 352: if (packet_length != PACKET_MAX_SIZE && mac && mac->enabled)
1.201 markus 353: state->packet_discard_mac = mac;
354: if (sshbuf_len(state->input) >= discard &&
355: (r = ssh_packet_stop_discard(ssh)) != 0)
356: return r;
357: state->packet_discard = discard - sshbuf_len(state->input);
358: return 0;
1.159 markus 359: }
360:
1.19 markus 361: /* Returns 1 if remote host is connected via socket, 0 if not. */
362:
363: int
1.201 markus 364: ssh_packet_connection_is_on_socket(struct ssh *ssh)
1.19 markus 365: {
1.201 markus 366: struct session_state *state = ssh->state;
1.19 markus 367: struct sockaddr_storage from, to;
368: socklen_t fromlen, tolen;
369:
370: /* filedescriptors in and out are the same, so it's a socket */
1.201 markus 371: if (state->connection_in == state->connection_out)
1.19 markus 372: return 1;
373: fromlen = sizeof(from);
374: memset(&from, 0, sizeof(from));
1.201 markus 375: if (getpeername(state->connection_in, (struct sockaddr *)&from,
1.161 andreas 376: &fromlen) < 0)
1.19 markus 377: return 0;
378: tolen = sizeof(to);
379: memset(&to, 0, sizeof(to));
1.201 markus 380: if (getpeername(state->connection_out, (struct sockaddr *)&to,
1.161 andreas 381: &tolen) < 0)
1.19 markus 382: return 0;
383: if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
384: return 0;
385: if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
386: return 0;
387: return 1;
388: }
389:
1.91 markus 390: void
1.201 markus 391: ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
1.91 markus 392: {
1.201 markus 393: if (ibytes)
394: *ibytes = ssh->state->p_read.bytes;
395: if (obytes)
396: *obytes = ssh->state->p_send.bytes;
1.91 markus 397: }
1.125 deraadt 398:
1.91 markus 399: int
1.201 markus 400: ssh_packet_connection_af(struct ssh *ssh)
1.19 markus 401: {
402: struct sockaddr_storage to;
1.21 deraadt 403: socklen_t tolen = sizeof(to);
1.19 markus 404:
405: memset(&to, 0, sizeof(to));
1.201 markus 406: if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
1.161 andreas 407: &tolen) < 0)
1.19 markus 408: return 0;
1.173 djm 409: return to.ss_family;
1.19 markus 410: }
411:
1.1 deraadt 412: /* Sets the connection into non-blocking mode. */
413:
1.2 provos 414: void
1.201 markus 415: ssh_packet_set_nonblocking(struct ssh *ssh)
1.1 deraadt 416: {
1.14 markus 417: /* Set the socket into non-blocking mode. */
1.201 markus 418: set_nonblock(ssh->state->connection_in);
1.14 markus 419:
1.201 markus 420: if (ssh->state->connection_out != ssh->state->connection_in)
421: set_nonblock(ssh->state->connection_out);
1.1 deraadt 422: }
423:
424: /* Returns the socket used for reading. */
425:
1.2 provos 426: int
1.201 markus 427: ssh_packet_get_connection_in(struct ssh *ssh)
1.1 deraadt 428: {
1.201 markus 429: return ssh->state->connection_in;
1.1 deraadt 430: }
431:
432: /* Returns the descriptor used for writing. */
433:
1.2 provos 434: int
1.201 markus 435: ssh_packet_get_connection_out(struct ssh *ssh)
1.1 deraadt 436: {
1.201 markus 437: return ssh->state->connection_out;
438: }
439:
440: /*
441: * Returns the IP-address of the remote host as a string. The returned
442: * string must not be freed.
443: */
444:
445: const char *
446: ssh_remote_ipaddr(struct ssh *ssh)
447: {
1.220 djm 448: const int sock = ssh->state->connection_in;
449:
1.201 markus 450: /* Check whether we have cached the ipaddr. */
1.220 djm 451: if (ssh->remote_ipaddr == NULL) {
452: if (ssh_packet_connection_is_on_socket(ssh)) {
453: ssh->remote_ipaddr = get_peer_ipaddr(sock);
454: ssh->remote_port = get_sock_port(sock, 0);
455: } else {
456: ssh->remote_ipaddr = strdup("UNKNOWN");
457: ssh->remote_port = 0;
458: }
459: }
1.201 markus 460: return ssh->remote_ipaddr;
1.1 deraadt 461: }
462:
1.220 djm 463: /* Returns the port number of the remote host. */
464:
465: int
466: ssh_remote_port(struct ssh *ssh)
467: {
468: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
469: return ssh->remote_port;
470: }
471:
1.1 deraadt 472: /* Closes the connection and clears and frees internal data structures. */
473:
1.2 provos 474: void
1.201 markus 475: ssh_packet_close(struct ssh *ssh)
1.1 deraadt 476: {
1.201 markus 477: struct session_state *state = ssh->state;
478: int r;
479: u_int mode;
480:
481: if (!state->initialized)
1.14 markus 482: return;
1.201 markus 483: state->initialized = 0;
484: if (state->connection_in == state->connection_out) {
485: shutdown(state->connection_out, SHUT_RDWR);
486: close(state->connection_out);
1.14 markus 487: } else {
1.201 markus 488: close(state->connection_in);
489: close(state->connection_out);
1.14 markus 490: }
1.201 markus 491: sshbuf_free(state->input);
492: sshbuf_free(state->output);
493: sshbuf_free(state->outgoing_packet);
494: sshbuf_free(state->incoming_packet);
495: for (mode = 0; mode < MODE_MAX; mode++)
496: kex_free_newkeys(state->newkeys[mode]);
497: if (state->compression_buffer) {
498: sshbuf_free(state->compression_buffer);
499: if (state->compression_out_started) {
500: z_streamp stream = &state->compression_out_stream;
501: debug("compress outgoing: "
502: "raw data %llu, compressed %llu, factor %.2f",
503: (unsigned long long)stream->total_in,
504: (unsigned long long)stream->total_out,
505: stream->total_in == 0 ? 0.0 :
506: (double) stream->total_out / stream->total_in);
507: if (state->compression_out_failures == 0)
508: deflateEnd(stream);
509: }
510: if (state->compression_in_started) {
511: z_streamp stream = &state->compression_out_stream;
512: debug("compress incoming: "
513: "raw data %llu, compressed %llu, factor %.2f",
514: (unsigned long long)stream->total_out,
515: (unsigned long long)stream->total_in,
516: stream->total_out == 0 ? 0.0 :
517: (double) stream->total_in / stream->total_out);
518: if (state->compression_in_failures == 0)
519: inflateEnd(stream);
520: }
1.14 markus 521: }
1.201 markus 522: if ((r = cipher_cleanup(&state->send_context)) != 0)
523: error("%s: cipher_cleanup failed: %s", __func__, ssh_err(r));
524: if ((r = cipher_cleanup(&state->receive_context)) != 0)
525: error("%s: cipher_cleanup failed: %s", __func__, ssh_err(r));
1.219 mmcc 526: free(ssh->remote_ipaddr);
527: ssh->remote_ipaddr = NULL;
1.201 markus 528: free(ssh->state);
529: ssh->state = NULL;
1.1 deraadt 530: }
531:
532: /* Sets remote side protocol flags. */
533:
1.2 provos 534: void
1.201 markus 535: ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
1.1 deraadt 536: {
1.201 markus 537: ssh->state->remote_protocol_flags = protocol_flags;
1.1 deraadt 538: }
539:
540: /* Returns the remote protocol flags set earlier by the above function. */
541:
1.40 markus 542: u_int
1.201 markus 543: ssh_packet_get_protocol_flags(struct ssh *ssh)
1.1 deraadt 544: {
1.201 markus 545: return ssh->state->remote_protocol_flags;
1.1 deraadt 546: }
547:
1.16 markus 548: /*
549: * Starts packet compression from the next packet on in both directions.
550: * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
551: */
1.1 deraadt 552:
1.201 markus 553: static int
554: ssh_packet_init_compression(struct ssh *ssh)
1.60 markus 555: {
1.201 markus 556: if (!ssh->state->compression_buffer &&
557: ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
558: return SSH_ERR_ALLOC_FAIL;
559: return 0;
1.60 markus 560: }
561:
1.201 markus 562: static int
563: start_compression_out(struct ssh *ssh, int level)
1.1 deraadt 564: {
1.201 markus 565: if (level < 1 || level > 9)
566: return SSH_ERR_INVALID_ARGUMENT;
567: debug("Enabling compression at level %d.", level);
568: if (ssh->state->compression_out_started == 1)
569: deflateEnd(&ssh->state->compression_out_stream);
570: switch (deflateInit(&ssh->state->compression_out_stream, level)) {
571: case Z_OK:
572: ssh->state->compression_out_started = 1;
573: break;
574: case Z_MEM_ERROR:
575: return SSH_ERR_ALLOC_FAIL;
576: default:
577: return SSH_ERR_INTERNAL_ERROR;
578: }
579: return 0;
1.1 deraadt 580: }
581:
1.201 markus 582: static int
583: start_compression_in(struct ssh *ssh)
584: {
585: if (ssh->state->compression_in_started == 1)
586: inflateEnd(&ssh->state->compression_in_stream);
587: switch (inflateInit(&ssh->state->compression_in_stream)) {
588: case Z_OK:
589: ssh->state->compression_in_started = 1;
590: break;
591: case Z_MEM_ERROR:
592: return SSH_ERR_ALLOC_FAIL;
593: default:
594: return SSH_ERR_INTERNAL_ERROR;
595: }
596: return 0;
597: }
1.95 markus 598:
1.201 markus 599: int
600: ssh_packet_start_compression(struct ssh *ssh, int level)
1.1 deraadt 601: {
1.197 djm 602: int r;
1.97 deraadt 603:
1.201 markus 604: if (ssh->state->packet_compression && !compat20)
605: return SSH_ERR_INTERNAL_ERROR;
606: ssh->state->packet_compression = 1;
607: if ((r = ssh_packet_init_compression(ssh)) != 0 ||
608: (r = start_compression_in(ssh)) != 0 ||
609: (r = start_compression_out(ssh, level)) != 0)
610: return r;
611: return 0;
1.95 markus 612: }
613:
1.201 markus 614: /* XXX remove need for separate compression buffer */
615: static int
616: compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.95 markus 617: {
1.201 markus 618: u_char buf[4096];
619: int r, status;
620:
621: if (ssh->state->compression_out_started != 1)
622: return SSH_ERR_INTERNAL_ERROR;
623:
624: /* This case is not handled below. */
625: if (sshbuf_len(in) == 0)
626: return 0;
627:
628: /* Input is the contents of the input buffer. */
629: if ((ssh->state->compression_out_stream.next_in =
630: sshbuf_mutable_ptr(in)) == NULL)
631: return SSH_ERR_INTERNAL_ERROR;
632: ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
633:
634: /* Loop compressing until deflate() returns with avail_out != 0. */
635: do {
636: /* Set up fixed-size output buffer. */
637: ssh->state->compression_out_stream.next_out = buf;
638: ssh->state->compression_out_stream.avail_out = sizeof(buf);
639:
640: /* Compress as much data into the buffer as possible. */
641: status = deflate(&ssh->state->compression_out_stream,
642: Z_PARTIAL_FLUSH);
643: switch (status) {
644: case Z_MEM_ERROR:
645: return SSH_ERR_ALLOC_FAIL;
646: case Z_OK:
647: /* Append compressed data to output_buffer. */
648: if ((r = sshbuf_put(out, buf, sizeof(buf) -
649: ssh->state->compression_out_stream.avail_out)) != 0)
650: return r;
651: break;
652: case Z_STREAM_ERROR:
653: default:
654: ssh->state->compression_out_failures++;
655: return SSH_ERR_INVALID_FORMAT;
656: }
657: } while (ssh->state->compression_out_stream.avail_out == 0);
658: return 0;
1.1 deraadt 659: }
660:
1.201 markus 661: static int
662: uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.1 deraadt 663: {
1.201 markus 664: u_char buf[4096];
665: int r, status;
1.1 deraadt 666:
1.201 markus 667: if (ssh->state->compression_in_started != 1)
668: return SSH_ERR_INTERNAL_ERROR;
1.25 markus 669:
1.201 markus 670: if ((ssh->state->compression_in_stream.next_in =
671: sshbuf_mutable_ptr(in)) == NULL)
672: return SSH_ERR_INTERNAL_ERROR;
673: ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
1.97 deraadt 674:
1.201 markus 675: for (;;) {
676: /* Set up fixed-size output buffer. */
677: ssh->state->compression_in_stream.next_out = buf;
678: ssh->state->compression_in_stream.avail_out = sizeof(buf);
679:
680: status = inflate(&ssh->state->compression_in_stream,
681: Z_PARTIAL_FLUSH);
682: switch (status) {
683: case Z_OK:
684: if ((r = sshbuf_put(out, buf, sizeof(buf) -
685: ssh->state->compression_in_stream.avail_out)) != 0)
686: return r;
687: break;
688: case Z_BUF_ERROR:
689: /*
690: * Comments in zlib.h say that we should keep calling
691: * inflate() until we get an error. This appears to
692: * be the error that we get.
693: */
694: return 0;
695: case Z_DATA_ERROR:
696: return SSH_ERR_INVALID_FORMAT;
697: case Z_MEM_ERROR:
698: return SSH_ERR_ALLOC_FAIL;
699: case Z_STREAM_ERROR:
700: default:
701: ssh->state->compression_in_failures++;
702: return SSH_ERR_INTERNAL_ERROR;
703: }
704: }
705: /* NOTREACHED */
1.1 deraadt 706: }
1.125 deraadt 707:
1.201 markus 708: /* Serialise compression state into a blob for privsep */
709: static int
710: ssh_packet_get_compress_state(struct sshbuf *m, struct ssh *ssh)
1.1 deraadt 711: {
1.201 markus 712: struct session_state *state = ssh->state;
713: struct sshbuf *b;
714: int r;
715:
716: if ((b = sshbuf_new()) == NULL)
717: return SSH_ERR_ALLOC_FAIL;
718: if (state->compression_in_started) {
719: if ((r = sshbuf_put_string(b, &state->compression_in_stream,
720: sizeof(state->compression_in_stream))) != 0)
721: goto out;
722: } else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
723: goto out;
724: if (state->compression_out_started) {
725: if ((r = sshbuf_put_string(b, &state->compression_out_stream,
726: sizeof(state->compression_out_stream))) != 0)
727: goto out;
728: } else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
729: goto out;
730: r = sshbuf_put_stringb(m, b);
731: out:
732: sshbuf_free(b);
733: return r;
1.1 deraadt 734: }
1.125 deraadt 735:
1.201 markus 736: /* Deserialise compression state from a blob for privsep */
737: static int
738: ssh_packet_set_compress_state(struct ssh *ssh, struct sshbuf *m)
1.162 andreas 739: {
1.201 markus 740: struct session_state *state = ssh->state;
741: struct sshbuf *b = NULL;
742: int r;
743: const u_char *inblob, *outblob;
744: size_t inl, outl;
1.162 andreas 745:
1.201 markus 746: if ((r = sshbuf_froms(m, &b)) != 0)
747: goto out;
748: if ((r = sshbuf_get_string_direct(b, &inblob, &inl)) != 0 ||
749: (r = sshbuf_get_string_direct(b, &outblob, &outl)) != 0)
750: goto out;
751: if (inl == 0)
752: state->compression_in_started = 0;
753: else if (inl != sizeof(state->compression_in_stream)) {
754: r = SSH_ERR_INTERNAL_ERROR;
755: goto out;
756: } else {
757: state->compression_in_started = 1;
758: memcpy(&state->compression_in_stream, inblob, inl);
759: }
760: if (outl == 0)
761: state->compression_out_started = 0;
762: else if (outl != sizeof(state->compression_out_stream)) {
763: r = SSH_ERR_INTERNAL_ERROR;
764: goto out;
765: } else {
766: state->compression_out_started = 1;
767: memcpy(&state->compression_out_stream, outblob, outl);
768: }
769: r = 0;
770: out:
771: sshbuf_free(b);
772: return r;
1.1 deraadt 773: }
1.125 deraadt 774:
1.24 markus 775: void
1.201 markus 776: ssh_packet_set_compress_hooks(struct ssh *ssh, void *ctx,
777: void *(*allocfunc)(void *, u_int, u_int),
778: void (*freefunc)(void *, void *))
779: {
780: ssh->state->compression_out_stream.zalloc = (alloc_func)allocfunc;
781: ssh->state->compression_out_stream.zfree = (free_func)freefunc;
782: ssh->state->compression_out_stream.opaque = ctx;
783: ssh->state->compression_in_stream.zalloc = (alloc_func)allocfunc;
784: ssh->state->compression_in_stream.zfree = (free_func)freefunc;
785: ssh->state->compression_in_stream.opaque = ctx;
1.24 markus 786: }
1.125 deraadt 787:
1.201 markus 788: /*
789: * Causes any further packets to be encrypted using the given key. The same
790: * key is used for both sending and reception. However, both directions are
791: * encrypted independently of each other.
792: */
1.125 deraadt 793:
1.2 provos 794: void
1.201 markus 795: ssh_packet_set_encryption_key(struct ssh *ssh, const u_char *key, u_int keylen, int number)
1.1 deraadt 796: {
1.211 djm 797: #ifndef WITH_SSH1
798: fatal("no SSH protocol 1 support");
799: #else /* WITH_SSH1 */
1.201 markus 800: struct session_state *state = ssh->state;
801: const struct sshcipher *cipher = cipher_by_number(number);
802: int r;
803: const char *wmsg;
1.125 deraadt 804:
1.201 markus 805: if (cipher == NULL)
806: fatal("%s: unknown cipher number %d", __func__, number);
807: if (keylen < 20)
808: fatal("%s: keylen too small: %d", __func__, keylen);
809: if (keylen > SSH_SESSION_KEY_LENGTH)
810: fatal("%s: keylen too big: %d", __func__, keylen);
811: memcpy(state->ssh1_key, key, keylen);
812: state->ssh1_keylen = keylen;
813: if ((r = cipher_init(&state->send_context, cipher, key, keylen,
814: NULL, 0, CIPHER_ENCRYPT)) != 0 ||
815: (r = cipher_init(&state->receive_context, cipher, key, keylen,
816: NULL, 0, CIPHER_DECRYPT) != 0))
817: fatal("%s: cipher_init failed: %s", __func__, ssh_err(r));
818: if (!state->cipher_warning_done &&
819: ((wmsg = cipher_warning_message(&state->send_context)) != NULL ||
820: (wmsg = cipher_warning_message(&state->send_context)) != NULL)) {
821: error("Warning: %s", wmsg);
822: state->cipher_warning_done = 1;
823: }
1.211 djm 824: #endif /* WITH_SSH1 */
1.170 djm 825: }
826:
1.16 markus 827: /*
828: * Finalizes and sends the packet. If the encryption key has been set,
829: * encrypts the packet before sending.
830: */
1.14 markus 831:
1.201 markus 832: int
833: ssh_packet_send1(struct ssh *ssh)
1.1 deraadt 834: {
1.201 markus 835: struct session_state *state = ssh->state;
1.89 markus 836: u_char buf[8], *cp;
1.201 markus 837: int r, padding, len;
1.40 markus 838: u_int checksum;
1.14 markus 839:
1.16 markus 840: /*
841: * If using packet compression, compress the payload of the outgoing
842: * packet.
843: */
1.201 markus 844: if (state->packet_compression) {
845: sshbuf_reset(state->compression_buffer);
1.14 markus 846: /* Skip padding. */
1.201 markus 847: if ((r = sshbuf_consume(state->outgoing_packet, 8)) != 0)
848: goto out;
1.14 markus 849: /* padding */
1.201 markus 850: if ((r = sshbuf_put(state->compression_buffer,
851: "\0\0\0\0\0\0\0\0", 8)) != 0)
852: goto out;
853: if ((r = compress_buffer(ssh, state->outgoing_packet,
854: state->compression_buffer)) != 0)
855: goto out;
856: sshbuf_reset(state->outgoing_packet);
857: if ((r = sshbuf_putb(state->outgoing_packet,
858: state->compression_buffer)) != 0)
859: goto out;
1.14 markus 860: }
861: /* Compute packet length without padding (add checksum, remove padding). */
1.201 markus 862: len = sshbuf_len(state->outgoing_packet) + 4 - 8;
1.14 markus 863:
1.32 markus 864: /* Insert padding. Initialized to zero in packet_start1() */
1.14 markus 865: padding = 8 - len % 8;
1.201 markus 866: if (!state->send_context.plaintext) {
867: cp = sshbuf_mutable_ptr(state->outgoing_packet);
868: if (cp == NULL) {
869: r = SSH_ERR_INTERNAL_ERROR;
870: goto out;
1.14 markus 871: }
1.201 markus 872: arc4random_buf(cp + 8 - padding, padding);
1.14 markus 873: }
1.201 markus 874: if ((r = sshbuf_consume(state->outgoing_packet, 8 - padding)) != 0)
875: goto out;
1.14 markus 876:
877: /* Add check bytes. */
1.201 markus 878: checksum = ssh_crc32(sshbuf_ptr(state->outgoing_packet),
879: sshbuf_len(state->outgoing_packet));
880: POKE_U32(buf, checksum);
881: if ((r = sshbuf_put(state->outgoing_packet, buf, 4)) != 0)
882: goto out;
1.1 deraadt 883:
884: #ifdef PACKET_DEBUG
1.14 markus 885: fprintf(stderr, "packet_send plain: ");
1.201 markus 886: sshbuf_dump(state->outgoing_packet, stderr);
1.1 deraadt 887: #endif
888:
1.14 markus 889: /* Append to output. */
1.201 markus 890: POKE_U32(buf, len);
891: if ((r = sshbuf_put(state->output, buf, 4)) != 0)
892: goto out;
893: if ((r = sshbuf_reserve(state->output,
894: sshbuf_len(state->outgoing_packet), &cp)) != 0)
895: goto out;
896: if ((r = cipher_crypt(&state->send_context, 0, cp,
897: sshbuf_ptr(state->outgoing_packet),
898: sshbuf_len(state->outgoing_packet), 0, 0)) != 0)
899: goto out;
1.14 markus 900:
1.1 deraadt 901: #ifdef PACKET_DEBUG
1.14 markus 902: fprintf(stderr, "encrypted: ");
1.201 markus 903: sshbuf_dump(state->output, stderr);
1.1 deraadt 904: #endif
1.201 markus 905: state->p_send.packets++;
906: state->p_send.bytes += len +
907: sshbuf_len(state->outgoing_packet);
908: sshbuf_reset(state->outgoing_packet);
1.1 deraadt 909:
1.16 markus 910: /*
1.120 djm 911: * Note that the packet is now only buffered in output. It won't be
1.205 djm 912: * actually sent until ssh_packet_write_wait or ssh_packet_write_poll
913: * is called.
1.16 markus 914: */
1.201 markus 915: r = 0;
916: out:
917: return r;
1.1 deraadt 918: }
919:
1.201 markus 920: int
921: ssh_set_newkeys(struct ssh *ssh, int mode)
1.57 markus 922: {
1.201 markus 923: struct session_state *state = ssh->state;
924: struct sshenc *enc;
925: struct sshmac *mac;
926: struct sshcomp *comp;
927: struct sshcipher_ctx *cc;
1.105 markus 928: u_int64_t *max_blocks;
1.201 markus 929: const char *wmsg;
1.197 djm 930: int r, crypt_type;
1.57 markus 931:
1.100 markus 932: debug2("set_newkeys: mode %d", mode);
1.57 markus 933:
1.88 markus 934: if (mode == MODE_OUT) {
1.201 markus 935: cc = &state->send_context;
1.115 avsm 936: crypt_type = CIPHER_ENCRYPT;
1.201 markus 937: state->p_send.packets = state->p_send.blocks = 0;
938: max_blocks = &state->max_blocks_out;
1.88 markus 939: } else {
1.201 markus 940: cc = &state->receive_context;
1.115 avsm 941: crypt_type = CIPHER_DECRYPT;
1.201 markus 942: state->p_read.packets = state->p_read.blocks = 0;
943: max_blocks = &state->max_blocks_in;
1.88 markus 944: }
1.201 markus 945: if (state->newkeys[mode] != NULL) {
1.100 markus 946: debug("set_newkeys: rekeying");
1.201 markus 947: if ((r = cipher_cleanup(cc)) != 0)
948: return r;
949: enc = &state->newkeys[mode]->enc;
950: mac = &state->newkeys[mode]->mac;
951: comp = &state->newkeys[mode]->comp;
1.148 pvalchev 952: mac_clear(mac);
1.192 djm 953: explicit_bzero(enc->iv, enc->iv_len);
954: explicit_bzero(enc->key, enc->key_len);
955: explicit_bzero(mac->key, mac->key_len);
1.186 djm 956: free(enc->name);
957: free(enc->iv);
958: free(enc->key);
959: free(mac->name);
960: free(mac->key);
961: free(comp->name);
1.201 markus 962: free(state->newkeys[mode]);
1.57 markus 963: }
1.201 markus 964: /* move newkeys from kex to state */
965: if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
966: return SSH_ERR_INTERNAL_ERROR;
967: ssh->kex->newkeys[mode] = NULL;
968: enc = &state->newkeys[mode]->enc;
969: mac = &state->newkeys[mode]->mac;
970: comp = &state->newkeys[mode]->comp;
971: if (cipher_authlen(enc->cipher) == 0) {
972: if ((r = mac_init(mac)) != 0)
973: return r;
974: }
975: mac->enabled = 1;
1.57 markus 976: DBG(debug("cipher_init_context: %d", mode));
1.197 djm 977: if ((r = cipher_init(cc, enc->cipher, enc->key, enc->key_len,
978: enc->iv, enc->iv_len, crypt_type)) != 0)
1.201 markus 979: return r;
980: if (!state->cipher_warning_done &&
981: (wmsg = cipher_warning_message(cc)) != NULL) {
982: error("Warning: %s", wmsg);
983: state->cipher_warning_done = 1;
984: }
1.91 markus 985: /* Deleting the keys does not gain extra security */
1.192 djm 986: /* explicit_bzero(enc->iv, enc->block_size);
987: explicit_bzero(enc->key, enc->key_len);
988: explicit_bzero(mac->key, mac->key_len); */
1.118 markus 989: if ((comp->type == COMP_ZLIB ||
1.161 andreas 990: (comp->type == COMP_DELAYED &&
1.201 markus 991: state->after_authentication)) && comp->enabled == 0) {
992: if ((r = ssh_packet_init_compression(ssh)) < 0)
993: return r;
994: if (mode == MODE_OUT) {
995: if ((r = start_compression_out(ssh, 6)) != 0)
996: return r;
997: } else {
998: if ((r = start_compression_in(ssh)) != 0)
999: return r;
1000: }
1.57 markus 1001: comp->enabled = 1;
1002: }
1.109 markus 1003: /*
1004: * The 2^(blocksize*2) limit is too expensive for 3DES,
1005: * blowfish, etc, so enforce a 1GB limit for small blocksizes.
1006: */
1007: if (enc->block_size >= 16)
1008: *max_blocks = (u_int64_t)1 << (enc->block_size*2);
1009: else
1010: *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1.201 markus 1011: if (state->rekey_limit)
1.161 andreas 1012: *max_blocks = MIN(*max_blocks,
1.201 markus 1013: state->rekey_limit / enc->block_size);
1014: return 0;
1.57 markus 1015: }
1016:
1.16 markus 1017: /*
1.118 markus 1018: * Delayed compression for SSH2 is enabled after authentication:
1.143 dtucker 1019: * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1.118 markus 1020: * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
1021: */
1.201 markus 1022: static int
1023: ssh_packet_enable_delayed_compress(struct ssh *ssh)
1.118 markus 1024: {
1.201 markus 1025: struct session_state *state = ssh->state;
1026: struct sshcomp *comp = NULL;
1027: int r, mode;
1.118 markus 1028:
1029: /*
1030: * Remember that we are past the authentication step, so rekeying
1031: * with COMP_DELAYED will turn on compression immediately.
1032: */
1.201 markus 1033: state->after_authentication = 1;
1.118 markus 1034: for (mode = 0; mode < MODE_MAX; mode++) {
1.145 markus 1035: /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1.201 markus 1036: if (state->newkeys[mode] == NULL)
1.145 markus 1037: continue;
1.201 markus 1038: comp = &state->newkeys[mode]->comp;
1.118 markus 1039: if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1.201 markus 1040: if ((r = ssh_packet_init_compression(ssh)) != 0)
1041: return r;
1042: if (mode == MODE_OUT) {
1043: if ((r = start_compression_out(ssh, 6)) != 0)
1044: return r;
1045: } else {
1046: if ((r = start_compression_in(ssh)) != 0)
1047: return r;
1048: }
1.118 markus 1049: comp->enabled = 1;
1050: }
1051: }
1.201 markus 1052: return 0;
1.118 markus 1053: }
1054:
1055: /*
1.25 markus 1056: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1057: */
1.201 markus 1058: int
1059: ssh_packet_send2_wrapped(struct ssh *ssh)
1.25 markus 1060: {
1.201 markus 1061: struct session_state *state = ssh->state;
1.200 markus 1062: u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1.178 markus 1063: u_char padlen, pad = 0;
1.201 markus 1064: u_int authlen = 0, aadlen = 0;
1065: u_int len;
1066: struct sshenc *enc = NULL;
1067: struct sshmac *mac = NULL;
1068: struct sshcomp *comp = NULL;
1069: int r, block_size;
1070:
1071: if (state->newkeys[MODE_OUT] != NULL) {
1072: enc = &state->newkeys[MODE_OUT]->enc;
1073: mac = &state->newkeys[MODE_OUT]->mac;
1074: comp = &state->newkeys[MODE_OUT]->comp;
1.180 markus 1075: /* disable mac for authenticated encryption */
1076: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1077: mac = NULL;
1.25 markus 1078: }
1.88 markus 1079: block_size = enc ? enc->block_size : 8;
1.180 markus 1080: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1081:
1.201 markus 1082: type = (sshbuf_ptr(state->outgoing_packet))[5];
1.25 markus 1083:
1084: #ifdef PACKET_DEBUG
1085: fprintf(stderr, "plain: ");
1.201 markus 1086: sshbuf_dump(state->outgoing_packet, stderr);
1.25 markus 1087: #endif
1088:
1089: if (comp && comp->enabled) {
1.201 markus 1090: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1091: /* skip header, compress only payload */
1.201 markus 1092: if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1093: goto out;
1094: sshbuf_reset(state->compression_buffer);
1095: if ((r = compress_buffer(ssh, state->outgoing_packet,
1096: state->compression_buffer)) != 0)
1097: goto out;
1098: sshbuf_reset(state->outgoing_packet);
1099: if ((r = sshbuf_put(state->outgoing_packet,
1100: "\0\0\0\0\0", 5)) != 0 ||
1101: (r = sshbuf_putb(state->outgoing_packet,
1102: state->compression_buffer)) != 0)
1103: goto out;
1104: DBG(debug("compression: raw %d compressed %zd", len,
1105: sshbuf_len(state->outgoing_packet)));
1.25 markus 1106: }
1107:
1108: /* sizeof (packet_len + pad_len + payload) */
1.201 markus 1109: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1110:
1111: /*
1112: * calc size of padding, alloc space, get random data,
1113: * minimum padding is 4 bytes
1114: */
1.178 markus 1115: len -= aadlen; /* packet length is not encrypted for EtM modes */
1.25 markus 1116: padlen = block_size - (len % block_size);
1117: if (padlen < 4)
1118: padlen += block_size;
1.201 markus 1119: if (state->extra_pad) {
1.71 markus 1120: /* will wrap if extra_pad+padlen > 255 */
1.201 markus 1121: state->extra_pad =
1122: roundup(state->extra_pad, block_size);
1123: pad = state->extra_pad -
1124: ((len + padlen) % state->extra_pad);
1.193 djm 1125: DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1.201 markus 1126: __func__, pad, len, padlen, state->extra_pad));
1.71 markus 1127: padlen += pad;
1.201 markus 1128: state->extra_pad = 0;
1.71 markus 1129: }
1.201 markus 1130: if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1131: goto out;
1132: if (enc && !state->send_context.plaintext) {
1.32 markus 1133: /* random padding */
1.201 markus 1134: arc4random_buf(cp, padlen);
1.32 markus 1135: } else {
1136: /* clear padding */
1.192 djm 1137: explicit_bzero(cp, padlen);
1.25 markus 1138: }
1.178 markus 1139: /* sizeof (packet_len + pad_len + payload + padding) */
1.201 markus 1140: len = sshbuf_len(state->outgoing_packet);
1141: cp = sshbuf_mutable_ptr(state->outgoing_packet);
1142: if (cp == NULL) {
1143: r = SSH_ERR_INTERNAL_ERROR;
1144: goto out;
1145: }
1.25 markus 1146: /* packet_length includes payload, padding and padding length field */
1.201 markus 1147: POKE_U32(cp, len - 4);
1.89 markus 1148: cp[4] = padlen;
1.178 markus 1149: DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1150: len, padlen, aadlen));
1.25 markus 1151:
1152: /* compute MAC over seqnr and packet(length fields, payload, padding) */
1.178 markus 1153: if (mac && mac->enabled && !mac->etm) {
1.201 markus 1154: if ((r = mac_compute(mac, state->p_send.seqnr,
1155: sshbuf_ptr(state->outgoing_packet), len,
1.200 markus 1156: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1157: goto out;
1158: DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1.25 markus 1159: }
1160: /* encrypt packet and append to output buffer. */
1.201 markus 1161: if ((r = sshbuf_reserve(state->output,
1162: sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1163: goto out;
1164: if ((r = cipher_crypt(&state->send_context, state->p_send.seqnr, cp,
1165: sshbuf_ptr(state->outgoing_packet),
1166: len - aadlen, aadlen, authlen)) != 0)
1167: goto out;
1.25 markus 1168: /* append unencrypted MAC */
1.178 markus 1169: if (mac && mac->enabled) {
1170: if (mac->etm) {
1171: /* EtM: compute mac over aadlen + cipher text */
1.201 markus 1172: if ((r = mac_compute(mac, state->p_send.seqnr,
1173: cp, len, macbuf, sizeof(macbuf))) != 0)
1174: goto out;
1.178 markus 1175: DBG(debug("done calc MAC(EtM) out #%d",
1.201 markus 1176: state->p_send.seqnr));
1.178 markus 1177: }
1.201 markus 1178: if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1179: goto out;
1.178 markus 1180: }
1.25 markus 1181: #ifdef PACKET_DEBUG
1182: fprintf(stderr, "encrypted: ");
1.201 markus 1183: sshbuf_dump(state->output, stderr);
1.25 markus 1184: #endif
1.29 markus 1185: /* increment sequence number for outgoing packets */
1.201 markus 1186: if (++state->p_send.seqnr == 0)
1.106 itojun 1187: logit("outgoing seqnr wraps around");
1.201 markus 1188: if (++state->p_send.packets == 0)
1189: if (!(ssh->compat & SSH_BUG_NOREKEY))
1190: return SSH_ERR_NEED_REKEY;
1191: state->p_send.blocks += len / block_size;
1192: state->p_send.bytes += len;
1193: sshbuf_reset(state->outgoing_packet);
1.25 markus 1194:
1.57 markus 1195: if (type == SSH2_MSG_NEWKEYS)
1.201 markus 1196: r = ssh_set_newkeys(ssh, MODE_OUT);
1197: else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1198: r = ssh_packet_enable_delayed_compress(ssh);
1199: else
1200: r = 0;
1201: out:
1202: return r;
1.25 markus 1203: }
1204:
1.201 markus 1205: int
1206: ssh_packet_send2(struct ssh *ssh)
1.105 markus 1207: {
1.201 markus 1208: struct session_state *state = ssh->state;
1.105 markus 1209: struct packet *p;
1.201 markus 1210: u_char type;
1211: int r;
1.105 markus 1212:
1.201 markus 1213: type = sshbuf_ptr(state->outgoing_packet)[5];
1.105 markus 1214:
1215: /* during rekeying we can only send key exchange messages */
1.201 markus 1216: if (state->rekeying) {
1.175 markus 1217: if ((type < SSH2_MSG_TRANSPORT_MIN) ||
1218: (type > SSH2_MSG_TRANSPORT_MAX) ||
1219: (type == SSH2_MSG_SERVICE_REQUEST) ||
1.218 markus 1220: (type == SSH2_MSG_SERVICE_ACCEPT) ||
1221: (type == SSH2_MSG_EXT_INFO)) {
1.105 markus 1222: debug("enqueue packet: %u", type);
1.201 markus 1223: p = calloc(1, sizeof(*p));
1224: if (p == NULL)
1225: return SSH_ERR_ALLOC_FAIL;
1.105 markus 1226: p->type = type;
1.201 markus 1227: p->payload = state->outgoing_packet;
1228: TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1229: state->outgoing_packet = sshbuf_new();
1230: if (state->outgoing_packet == NULL)
1231: return SSH_ERR_ALLOC_FAIL;
1232: return 0;
1.105 markus 1233: }
1234: }
1235:
1236: /* rekeying starts with sending KEXINIT */
1237: if (type == SSH2_MSG_KEXINIT)
1.201 markus 1238: state->rekeying = 1;
1.105 markus 1239:
1.201 markus 1240: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1241: return r;
1.105 markus 1242:
1243: /* after a NEWKEYS message we can send the complete queue */
1244: if (type == SSH2_MSG_NEWKEYS) {
1.201 markus 1245: state->rekeying = 0;
1246: state->rekey_time = monotime();
1247: while ((p = TAILQ_FIRST(&state->outgoing))) {
1.105 markus 1248: type = p->type;
1249: debug("dequeue packet: %u", type);
1.201 markus 1250: sshbuf_free(state->outgoing_packet);
1251: state->outgoing_packet = p->payload;
1252: TAILQ_REMOVE(&state->outgoing, p, next);
1.186 djm 1253: free(p);
1.201 markus 1254: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1255: return r;
1.105 markus 1256: }
1257: }
1.201 markus 1258: return 0;
1.25 markus 1259: }
1260:
1261: /*
1.16 markus 1262: * Waits until a packet has been received, and returns its type. Note that
1263: * no other data is processed until this returns, so this function should not
1264: * be used during the interactive session.
1265: */
1.1 deraadt 1266:
1.2 provos 1267: int
1.201 markus 1268: ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.1 deraadt 1269: {
1.201 markus 1270: struct session_state *state = ssh->state;
1271: int len, r, ms_remain, cont;
1.56 millert 1272: fd_set *setp;
1.14 markus 1273: char buf[8192];
1.155 deraadt 1274: struct timeval timeout, start, *timeoutp = NULL;
1275:
1.25 markus 1276: DBG(debug("packet_read()"));
1.14 markus 1277:
1.214 deraadt 1278: setp = calloc(howmany(state->connection_in + 1,
1.161 andreas 1279: NFDBITS), sizeof(fd_mask));
1.201 markus 1280: if (setp == NULL)
1281: return SSH_ERR_ALLOC_FAIL;
1.56 millert 1282:
1.205 djm 1283: /*
1284: * Since we are blocking, ensure that all written packets have
1285: * been sent.
1286: */
1.210 markus 1287: if ((r = ssh_packet_write_wait(ssh)) != 0)
1288: goto out;
1.14 markus 1289:
1290: /* Stay in the loop until we have received a complete packet. */
1291: for (;;) {
1292: /* Try to read a packet from the buffer. */
1.201 markus 1293: r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1294: if (r != 0)
1295: break;
1.62 markus 1296: if (!compat20 && (
1.201 markus 1297: *typep == SSH_SMSG_SUCCESS
1298: || *typep == SSH_SMSG_FAILURE
1299: || *typep == SSH_CMSG_EOF
1300: || *typep == SSH_CMSG_EXIT_CONFIRMATION))
1301: if ((r = sshpkt_get_end(ssh)) != 0)
1302: break;
1.14 markus 1303: /* If we got a packet, return it. */
1.201 markus 1304: if (*typep != SSH_MSG_NONE)
1305: break;
1.16 markus 1306: /*
1307: * Otherwise, wait for some data to arrive, add it to the
1308: * buffer, and try again.
1309: */
1.201 markus 1310: memset(setp, 0, howmany(state->connection_in + 1,
1.161 andreas 1311: NFDBITS) * sizeof(fd_mask));
1.201 markus 1312: FD_SET(state->connection_in, setp);
1.16 markus 1313:
1.201 markus 1314: if (state->packet_timeout_ms > 0) {
1315: ms_remain = state->packet_timeout_ms;
1.154 dtucker 1316: timeoutp = &timeout;
1317: }
1.14 markus 1318: /* Wait for some data to arrive. */
1.154 dtucker 1319: for (;;) {
1.201 markus 1320: if (state->packet_timeout_ms != -1) {
1.154 dtucker 1321: ms_to_timeval(&timeout, ms_remain);
1322: gettimeofday(&start, NULL);
1323: }
1.201 markus 1324: if ((r = select(state->connection_in + 1, setp,
1.161 andreas 1325: NULL, NULL, timeoutp)) >= 0)
1.154 dtucker 1326: break;
1.161 andreas 1327: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 1328: break;
1.201 markus 1329: if (state->packet_timeout_ms == -1)
1.154 dtucker 1330: continue;
1331: ms_subtract_diff(&start, &ms_remain);
1332: if (ms_remain <= 0) {
1.201 markus 1333: r = 0;
1.154 dtucker 1334: break;
1335: }
1336: }
1.204 djm 1337: if (r == 0)
1338: return SSH_ERR_CONN_TIMEOUT;
1.14 markus 1339: /* Read data from the socket. */
1.163 andreas 1340: do {
1341: cont = 0;
1.201 markus 1342: len = roaming_read(state->connection_in, buf,
1.163 andreas 1343: sizeof(buf), &cont);
1344: } while (len == 0 && cont);
1.210 markus 1345: if (len == 0) {
1346: r = SSH_ERR_CONN_CLOSED;
1347: goto out;
1348: }
1349: if (len < 0) {
1350: r = SSH_ERR_SYSTEM_ERROR;
1351: goto out;
1352: }
1.204 djm 1353:
1.14 markus 1354: /* Append it to the buffer. */
1.204 djm 1355: if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1.210 markus 1356: goto out;
1.14 markus 1357: }
1.210 markus 1358: out:
1.201 markus 1359: free(setp);
1360: return r;
1.1 deraadt 1361: }
1362:
1.77 djm 1363: int
1.201 markus 1364: ssh_packet_read(struct ssh *ssh)
1.77 djm 1365: {
1.201 markus 1366: u_char type;
1367: int r;
1368:
1369: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1370: fatal("%s: %s", __func__, ssh_err(r));
1371: return type;
1.77 djm 1372: }
1373:
1.16 markus 1374: /*
1375: * Waits until a packet has been received, verifies that its type matches
1376: * that given, and gives a fatal error and exits if there is a mismatch.
1377: */
1.1 deraadt 1378:
1.205 djm 1379: int
1380: ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1.1 deraadt 1381: {
1.205 djm 1382: int r;
1383: u_char type;
1.1 deraadt 1384:
1.205 djm 1385: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1386: return r;
1387: if (type != expected_type) {
1388: if ((r = sshpkt_disconnect(ssh,
1.201 markus 1389: "Protocol error: expected packet type %d, got %d",
1.205 djm 1390: expected_type, type)) != 0)
1391: return r;
1392: return SSH_ERR_PROTOCOL_ERROR;
1393: }
1394: return 0;
1.1 deraadt 1395: }
1396:
1397: /* Checks if a full packet is available in the data received so far via
1.14 markus 1398: * packet_process_incoming. If so, reads the packet; otherwise returns
1399: * SSH_MSG_NONE. This does not wait for data from the connection.
1400: *
1.150 dtucker 1401: * SSH_MSG_DISCONNECT is handled specially here. Also,
1402: * SSH_MSG_IGNORE messages are skipped by this function and are never returned
1403: * to higher levels.
1.14 markus 1404: */
1.1 deraadt 1405:
1.201 markus 1406: int
1407: ssh_packet_read_poll1(struct ssh *ssh, u_char *typep)
1.1 deraadt 1408: {
1.201 markus 1409: struct session_state *state = ssh->state;
1.40 markus 1410: u_int len, padded_len;
1.205 djm 1411: const char *emsg;
1.201 markus 1412: const u_char *cp;
1413: u_char *p;
1.40 markus 1414: u_int checksum, stored_checksum;
1.201 markus 1415: int r;
1416:
1417: *typep = SSH_MSG_NONE;
1.14 markus 1418:
1419: /* Check if input size is less than minimum packet size. */
1.201 markus 1420: if (sshbuf_len(state->input) < 4 + 8)
1421: return 0;
1.14 markus 1422: /* Get length of incoming packet. */
1.201 markus 1423: len = PEEK_U32(sshbuf_ptr(state->input));
1.205 djm 1424: if (len < 1 + 2 + 2 || len > 256 * 1024) {
1425: if ((r = sshpkt_disconnect(ssh, "Bad packet length %u",
1426: len)) != 0)
1427: return r;
1428: return SSH_ERR_CONN_CORRUPT;
1429: }
1.14 markus 1430: padded_len = (len + 8) & ~7;
1431:
1432: /* Check if the packet has been entirely received. */
1.201 markus 1433: if (sshbuf_len(state->input) < 4 + padded_len)
1434: return 0;
1.14 markus 1435:
1436: /* The entire packet is in buffer. */
1437:
1438: /* Consume packet length. */
1.201 markus 1439: if ((r = sshbuf_consume(state->input, 4)) != 0)
1440: goto out;
1.14 markus 1441:
1.62 markus 1442: /*
1443: * Cryptographic attack detector for ssh
1444: * (C)1998 CORE-SDI, Buenos Aires Argentina
1445: * Ariel Futoransky(futo@core-sdi.com)
1446: */
1.201 markus 1447: if (!state->receive_context.plaintext) {
1.205 djm 1448: emsg = NULL;
1.201 markus 1449: switch (detect_attack(&state->deattack,
1450: sshbuf_ptr(state->input), padded_len)) {
1451: case DEATTACK_OK:
1452: break;
1.144 djm 1453: case DEATTACK_DETECTED:
1.205 djm 1454: emsg = "crc32 compensation attack detected";
1455: break;
1.144 djm 1456: case DEATTACK_DOS_DETECTED:
1.205 djm 1457: emsg = "deattack denial of service detected";
1458: break;
1.201 markus 1459: default:
1.205 djm 1460: emsg = "deattack error";
1461: break;
1462: }
1463: if (emsg != NULL) {
1464: error("%s", emsg);
1465: if ((r = sshpkt_disconnect(ssh, "%s", emsg)) != 0 ||
1466: (r = ssh_packet_write_wait(ssh)) != 0)
1467: return r;
1468: return SSH_ERR_CONN_CORRUPT;
1.144 djm 1469: }
1470: }
1.62 markus 1471:
1472: /* Decrypt data to incoming_packet. */
1.201 markus 1473: sshbuf_reset(state->incoming_packet);
1474: if ((r = sshbuf_reserve(state->incoming_packet, padded_len, &p)) != 0)
1475: goto out;
1476: if ((r = cipher_crypt(&state->receive_context, 0, p,
1477: sshbuf_ptr(state->input), padded_len, 0, 0)) != 0)
1478: goto out;
1.62 markus 1479:
1.201 markus 1480: if ((r = sshbuf_consume(state->input, padded_len)) != 0)
1481: goto out;
1.1 deraadt 1482:
1483: #ifdef PACKET_DEBUG
1.14 markus 1484: fprintf(stderr, "read_poll plain: ");
1.201 markus 1485: sshbuf_dump(state->incoming_packet, stderr);
1.1 deraadt 1486: #endif
1487:
1.14 markus 1488: /* Compute packet checksum. */
1.201 markus 1489: checksum = ssh_crc32(sshbuf_ptr(state->incoming_packet),
1490: sshbuf_len(state->incoming_packet) - 4);
1.14 markus 1491:
1492: /* Skip padding. */
1.201 markus 1493: if ((r = sshbuf_consume(state->incoming_packet, 8 - len % 8)) != 0)
1494: goto out;
1.14 markus 1495:
1496: /* Test check bytes. */
1.205 djm 1497: if (len != sshbuf_len(state->incoming_packet)) {
1498: error("%s: len %d != sshbuf_len %zd", __func__,
1.201 markus 1499: len, sshbuf_len(state->incoming_packet));
1.205 djm 1500: if ((r = sshpkt_disconnect(ssh, "invalid packet length")) != 0 ||
1501: (r = ssh_packet_write_wait(ssh)) != 0)
1502: return r;
1503: return SSH_ERR_CONN_CORRUPT;
1504: }
1.14 markus 1505:
1.201 markus 1506: cp = sshbuf_ptr(state->incoming_packet) + len - 4;
1507: stored_checksum = PEEK_U32(cp);
1.205 djm 1508: if (checksum != stored_checksum) {
1509: error("Corrupted check bytes on input");
1510: if ((r = sshpkt_disconnect(ssh, "connection corrupted")) != 0 ||
1511: (r = ssh_packet_write_wait(ssh)) != 0)
1512: return r;
1513: return SSH_ERR_CONN_CORRUPT;
1514: }
1.201 markus 1515: if ((r = sshbuf_consume_end(state->incoming_packet, 4)) < 0)
1516: goto out;
1517:
1518: if (state->packet_compression) {
1519: sshbuf_reset(state->compression_buffer);
1520: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1521: state->compression_buffer)) != 0)
1522: goto out;
1523: sshbuf_reset(state->incoming_packet);
1524: if ((r = sshbuf_putb(state->incoming_packet,
1525: state->compression_buffer)) != 0)
1526: goto out;
1527: }
1528: state->p_read.packets++;
1529: state->p_read.bytes += padded_len + 4;
1530: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1531: goto out;
1.205 djm 1532: if (*typep < SSH_MSG_MIN || *typep > SSH_MSG_MAX) {
1533: error("Invalid ssh1 packet type: %d", *typep);
1534: if ((r = sshpkt_disconnect(ssh, "invalid packet type")) != 0 ||
1535: (r = ssh_packet_write_wait(ssh)) != 0)
1536: return r;
1537: return SSH_ERR_PROTOCOL_ERROR;
1538: }
1.201 markus 1539: r = 0;
1540: out:
1541: return r;
1.1 deraadt 1542: }
1.14 markus 1543:
1.201 markus 1544: int
1545: ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1546: {
1.201 markus 1547: struct session_state *state = ssh->state;
1.40 markus 1548: u_int padlen, need;
1.201 markus 1549: u_char *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1550: u_int maclen, aadlen = 0, authlen = 0, block_size;
1551: struct sshenc *enc = NULL;
1552: struct sshmac *mac = NULL;
1553: struct sshcomp *comp = NULL;
1.200 markus 1554: int r;
1.201 markus 1555:
1556: *typep = SSH_MSG_NONE;
1557:
1558: if (state->packet_discard)
1559: return 0;
1560:
1561: if (state->newkeys[MODE_IN] != NULL) {
1562: enc = &state->newkeys[MODE_IN]->enc;
1563: mac = &state->newkeys[MODE_IN]->mac;
1564: comp = &state->newkeys[MODE_IN]->comp;
1.180 markus 1565: /* disable mac for authenticated encryption */
1566: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1567: mac = NULL;
1.25 markus 1568: }
1569: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.88 markus 1570: block_size = enc ? enc->block_size : 8;
1.180 markus 1571: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1572:
1.201 markus 1573: if (aadlen && state->packlen == 0) {
1574: if (cipher_get_length(&state->receive_context,
1575: &state->packlen, state->p_read.seqnr,
1576: sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1577: return 0;
1578: if (state->packlen < 1 + 4 ||
1579: state->packlen > PACKET_MAX_SIZE) {
1.178 markus 1580: #ifdef PACKET_DEBUG
1.201 markus 1581: sshbuf_dump(state->input, stderr);
1.178 markus 1582: #endif
1.201 markus 1583: logit("Bad packet length %u.", state->packlen);
1584: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1585: return r;
1.217 djm 1586: return SSH_ERR_CONN_CORRUPT;
1.178 markus 1587: }
1.201 markus 1588: sshbuf_reset(state->incoming_packet);
1589: } else if (state->packlen == 0) {
1.25 markus 1590: /*
1591: * check if input size is less than the cipher block size,
1592: * decrypt first block and extract length of incoming packet
1593: */
1.201 markus 1594: if (sshbuf_len(state->input) < block_size)
1595: return 0;
1596: sshbuf_reset(state->incoming_packet);
1597: if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1598: &cp)) != 0)
1599: goto out;
1600: if ((r = cipher_crypt(&state->receive_context,
1601: state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1602: block_size, 0, 0)) != 0)
1603: goto out;
1604: state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1605: if (state->packlen < 1 + 4 ||
1606: state->packlen > PACKET_MAX_SIZE) {
1.110 markus 1607: #ifdef PACKET_DEBUG
1.201 markus 1608: fprintf(stderr, "input: \n");
1609: sshbuf_dump(state->input, stderr);
1610: fprintf(stderr, "incoming_packet: \n");
1611: sshbuf_dump(state->incoming_packet, stderr);
1.110 markus 1612: #endif
1.201 markus 1613: logit("Bad packet length %u.", state->packlen);
1614: return ssh_packet_start_discard(ssh, enc, mac,
1615: state->packlen, PACKET_MAX_SIZE);
1.25 markus 1616: }
1.201 markus 1617: if ((r = sshbuf_consume(state->input, block_size)) != 0)
1618: goto out;
1.25 markus 1619: }
1.201 markus 1620: DBG(debug("input: packet len %u", state->packlen+4));
1621:
1.178 markus 1622: if (aadlen) {
1623: /* only the payload is encrypted */
1.201 markus 1624: need = state->packlen;
1.178 markus 1625: } else {
1626: /*
1627: * the payload size and the payload are encrypted, but we
1628: * have a partial packet of block_size bytes
1629: */
1.201 markus 1630: need = 4 + state->packlen - block_size;
1.178 markus 1631: }
1.180 markus 1632: DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1633: " aadlen %d", block_size, need, maclen, authlen, aadlen));
1.158 markus 1634: if (need % block_size != 0) {
1635: logit("padding error: need %d block %d mod %d",
1.25 markus 1636: need, block_size, need % block_size);
1.201 markus 1637: return ssh_packet_start_discard(ssh, enc, mac,
1638: state->packlen, PACKET_MAX_SIZE - block_size);
1.158 markus 1639: }
1.25 markus 1640: /*
1641: * check if the entire packet has been received and
1.178 markus 1642: * decrypt into incoming_packet:
1643: * 'aadlen' bytes are unencrypted, but authenticated.
1.180 markus 1644: * 'need' bytes are encrypted, followed by either
1645: * 'authlen' bytes of authentication tag or
1.178 markus 1646: * 'maclen' bytes of message authentication code.
1.25 markus 1647: */
1.201 markus 1648: if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1649: return 0;
1.25 markus 1650: #ifdef PACKET_DEBUG
1651: fprintf(stderr, "read_poll enc/full: ");
1.201 markus 1652: sshbuf_dump(state->input, stderr);
1.25 markus 1653: #endif
1.178 markus 1654: /* EtM: compute mac over encrypted input */
1.201 markus 1655: if (mac && mac->enabled && mac->etm) {
1656: if ((r = mac_compute(mac, state->p_read.seqnr,
1657: sshbuf_ptr(state->input), aadlen + need,
1.200 markus 1658: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1659: goto out;
1660: }
1661: if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1662: &cp)) != 0)
1663: goto out;
1664: if ((r = cipher_crypt(&state->receive_context, state->p_read.seqnr, cp,
1665: sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1666: goto out;
1667: if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1668: goto out;
1.25 markus 1669: /*
1670: * compute MAC over seqnr and packet,
1671: * increment sequence number for incoming packet
1672: */
1.29 markus 1673: if (mac && mac->enabled) {
1.178 markus 1674: if (!mac->etm)
1.201 markus 1675: if ((r = mac_compute(mac, state->p_read.seqnr,
1676: sshbuf_ptr(state->incoming_packet),
1677: sshbuf_len(state->incoming_packet),
1.200 markus 1678: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1679: goto out;
1680: if (timingsafe_bcmp(macbuf, sshbuf_ptr(state->input),
1.161 andreas 1681: mac->mac_len) != 0) {
1.159 markus 1682: logit("Corrupted MAC on input.");
1683: if (need > PACKET_MAX_SIZE)
1.201 markus 1684: return SSH_ERR_INTERNAL_ERROR;
1685: return ssh_packet_start_discard(ssh, enc, mac,
1686: state->packlen, PACKET_MAX_SIZE - need);
1687: }
1688:
1689: DBG(debug("MAC #%d ok", state->p_read.seqnr));
1690: if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1691: goto out;
1.25 markus 1692: }
1.77 djm 1693: if (seqnr_p != NULL)
1.201 markus 1694: *seqnr_p = state->p_read.seqnr;
1695: if (++state->p_read.seqnr == 0)
1.106 itojun 1696: logit("incoming seqnr wraps around");
1.201 markus 1697: if (++state->p_read.packets == 0)
1698: if (!(ssh->compat & SSH_BUG_NOREKEY))
1699: return SSH_ERR_NEED_REKEY;
1700: state->p_read.blocks += (state->packlen + 4) / block_size;
1701: state->p_read.bytes += state->packlen + 4;
1.25 markus 1702:
1703: /* get padlen */
1.201 markus 1704: padlen = sshbuf_ptr(state->incoming_packet)[4];
1.25 markus 1705: DBG(debug("input: padlen %d", padlen));
1.205 djm 1706: if (padlen < 4) {
1707: if ((r = sshpkt_disconnect(ssh,
1708: "Corrupted padlen %d on input.", padlen)) != 0 ||
1709: (r = ssh_packet_write_wait(ssh)) != 0)
1710: return r;
1711: return SSH_ERR_CONN_CORRUPT;
1712: }
1.25 markus 1713:
1714: /* skip packet size + padlen, discard padding */
1.201 markus 1715: if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1716: ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1717: goto out;
1.25 markus 1718:
1.201 markus 1719: DBG(debug("input: len before de-compress %zd",
1720: sshbuf_len(state->incoming_packet)));
1.25 markus 1721: if (comp && comp->enabled) {
1.201 markus 1722: sshbuf_reset(state->compression_buffer);
1723: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1724: state->compression_buffer)) != 0)
1725: goto out;
1726: sshbuf_reset(state->incoming_packet);
1727: if ((r = sshbuf_putb(state->incoming_packet,
1728: state->compression_buffer)) != 0)
1729: goto out;
1730: DBG(debug("input: len after de-compress %zd",
1731: sshbuf_len(state->incoming_packet)));
1.25 markus 1732: }
1733: /*
1734: * get packet type, implies consume.
1735: * return length of payload (without type field)
1736: */
1.201 markus 1737: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1738: goto out;
1.205 djm 1739: if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1740: if ((r = sshpkt_disconnect(ssh,
1741: "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1742: (r = ssh_packet_write_wait(ssh)) != 0)
1743: return r;
1744: return SSH_ERR_PROTOCOL_ERROR;
1745: }
1.201 markus 1746: if (*typep == SSH2_MSG_NEWKEYS)
1747: r = ssh_set_newkeys(ssh, MODE_IN);
1748: else if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1749: r = ssh_packet_enable_delayed_compress(ssh);
1750: else
1751: r = 0;
1.25 markus 1752: #ifdef PACKET_DEBUG
1.201 markus 1753: fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1754: sshbuf_dump(state->incoming_packet, stderr);
1.25 markus 1755: #endif
1.62 markus 1756: /* reset for next packet */
1.201 markus 1757: state->packlen = 0;
1758: out:
1759: return r;
1.25 markus 1760: }
1761:
1762: int
1.201 markus 1763: ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1764: {
1.201 markus 1765: struct session_state *state = ssh->state;
1.96 deraadt 1766: u_int reason, seqnr;
1.201 markus 1767: int r;
1768: u_char *msg;
1.62 markus 1769:
1.25 markus 1770: for (;;) {
1.201 markus 1771: msg = NULL;
1.62 markus 1772: if (compat20) {
1.201 markus 1773: r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1774: if (r != 0)
1775: return r;
1776: if (*typep) {
1777: state->keep_alive_timeouts = 0;
1778: DBG(debug("received packet type %d", *typep));
1.153 djm 1779: }
1.201 markus 1780: switch (*typep) {
1.150 dtucker 1781: case SSH2_MSG_IGNORE:
1.151 dtucker 1782: debug3("Received SSH2_MSG_IGNORE");
1.150 dtucker 1783: break;
1.25 markus 1784: case SSH2_MSG_DEBUG:
1.201 markus 1785: if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1786: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1787: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1.219 mmcc 1788: free(msg);
1.201 markus 1789: return r;
1790: }
1.25 markus 1791: debug("Remote: %.900s", msg);
1.186 djm 1792: free(msg);
1.25 markus 1793: break;
1794: case SSH2_MSG_DISCONNECT:
1.201 markus 1795: if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1796: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1797: return r;
1.182 djm 1798: /* Ignore normal client exit notifications */
1.201 markus 1799: do_log2(ssh->state->server_side &&
1.182 djm 1800: reason == SSH2_DISCONNECT_BY_APPLICATION ?
1801: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1.220 djm 1802: "Received disconnect from %s port %d:"
1803: "%u: %.400s", ssh_remote_ipaddr(ssh),
1804: ssh_remote_port(ssh), reason, msg);
1.186 djm 1805: free(msg);
1.201 markus 1806: return SSH_ERR_DISCONNECTED;
1.84 markus 1807: case SSH2_MSG_UNIMPLEMENTED:
1.201 markus 1808: if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1809: return r;
1.96 deraadt 1810: debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1811: seqnr);
1.150 dtucker 1812: break;
1.25 markus 1813: default:
1.201 markus 1814: return 0;
1.48 stevesk 1815: }
1.25 markus 1816: } else {
1.201 markus 1817: r = ssh_packet_read_poll1(ssh, typep);
1818: switch (*typep) {
1.188 djm 1819: case SSH_MSG_NONE:
1820: return SSH_MSG_NONE;
1.25 markus 1821: case SSH_MSG_IGNORE:
1822: break;
1823: case SSH_MSG_DEBUG:
1.201 markus 1824: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1825: return r;
1.25 markus 1826: debug("Remote: %.900s", msg);
1.186 djm 1827: free(msg);
1.25 markus 1828: break;
1829: case SSH_MSG_DISCONNECT:
1.201 markus 1830: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1831: return r;
1.220 djm 1832: error("Received disconnect from %s port %d: "
1833: "%.400s", ssh_remote_ipaddr(ssh),
1834: ssh_remote_port(ssh), msg);
1.201 markus 1835: free(msg);
1836: return SSH_ERR_DISCONNECTED;
1.25 markus 1837: default:
1.201 markus 1838: DBG(debug("received packet type %d", *typep));
1839: return 0;
1.48 stevesk 1840: }
1.25 markus 1841: }
1842: }
1843: }
1844:
1.16 markus 1845: /*
1846: * Buffers the given amount of input characters. This is intended to be used
1847: * together with packet_read_poll.
1848: */
1.1 deraadt 1849:
1.204 djm 1850: int
1.201 markus 1851: ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1.1 deraadt 1852: {
1.201 markus 1853: struct session_state *state = ssh->state;
1854: int r;
1855:
1856: if (state->packet_discard) {
1857: state->keep_alive_timeouts = 0; /* ?? */
1858: if (len >= state->packet_discard) {
1859: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1.204 djm 1860: return r;
1.201 markus 1861: }
1862: state->packet_discard -= len;
1.204 djm 1863: return 0;
1.159 markus 1864: }
1.201 markus 1865: if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1.204 djm 1866: return r;
1867:
1868: return 0;
1.28 markus 1869: }
1870:
1871: int
1.201 markus 1872: ssh_packet_remaining(struct ssh *ssh)
1.28 markus 1873: {
1.201 markus 1874: return sshbuf_len(ssh->state->incoming_packet);
1.1 deraadt 1875: }
1876:
1.16 markus 1877: /*
1878: * Sends a diagnostic message from the server to the client. This message
1879: * can be sent at any time (but not while constructing another message). The
1880: * message is printed immediately, but only if the client is being executed
1881: * in verbose mode. These messages are primarily intended to ease debugging
1882: * authentication problems. The length of the formatted message must not
1.205 djm 1883: * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1.16 markus 1884: */
1.2 provos 1885: void
1.201 markus 1886: ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1887: {
1.14 markus 1888: char buf[1024];
1889: va_list args;
1.201 markus 1890: int r;
1.39 markus 1891:
1.201 markus 1892: if (compat20 && (ssh->compat & SSH_BUG_DEBUG))
1.39 markus 1893: return;
1.14 markus 1894:
1895: va_start(args, fmt);
1896: vsnprintf(buf, sizeof(buf), fmt, args);
1897: va_end(args);
1898:
1.30 markus 1899: if (compat20) {
1.201 markus 1900: if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1901: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1902: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1903: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1904: (r = sshpkt_send(ssh)) != 0)
1905: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1906: } else {
1.201 markus 1907: if ((r = sshpkt_start(ssh, SSH_MSG_DEBUG)) != 0 ||
1908: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1909: (r = sshpkt_send(ssh)) != 0)
1910: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1911: }
1.205 djm 1912: if ((r = ssh_packet_write_wait(ssh)) != 0)
1913: fatal("%s: %s", __func__, ssh_err(r));
1914: }
1915:
1916: /*
1917: * Pretty-print connection-terminating errors and exit.
1918: */
1919: void
1920: sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1921: {
1922: switch (r) {
1923: case SSH_ERR_CONN_CLOSED:
1.220 djm 1924: logit("Connection closed by %.200s port %d",
1925: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.205 djm 1926: cleanup_exit(255);
1927: case SSH_ERR_CONN_TIMEOUT:
1.220 djm 1928: logit("Connection %s %.200s port %d timed out",
1929: ssh->state->server_side ? "from" : "to",
1930: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.205 djm 1931: cleanup_exit(255);
1.212 djm 1932: case SSH_ERR_DISCONNECTED:
1.220 djm 1933: logit("Disconnected from %.200s port %d",
1934: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 1935: cleanup_exit(255);
1936: case SSH_ERR_SYSTEM_ERROR:
1937: if (errno == ECONNRESET) {
1.220 djm 1938: logit("Connection reset by %.200s port %d",
1939: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 1940: cleanup_exit(255);
1.213 djm 1941: }
1942: /* FALLTHROUGH */
1943: case SSH_ERR_NO_CIPHER_ALG_MATCH:
1944: case SSH_ERR_NO_MAC_ALG_MATCH:
1945: case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1946: case SSH_ERR_NO_KEX_ALG_MATCH:
1947: case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1948: if (ssh && ssh->kex && ssh->kex->failed_choice) {
1.220 djm 1949: fatal("Unable to negotiate with %.200s port %d: %s. "
1.213 djm 1950: "Their offer: %s", ssh_remote_ipaddr(ssh),
1.220 djm 1951: ssh_remote_port(ssh), ssh_err(r),
1952: ssh->kex->failed_choice);
1.212 djm 1953: }
1954: /* FALLTHROUGH */
1.205 djm 1955: default:
1.220 djm 1956: fatal("%s%sConnection %s %.200s port %d: %s",
1.205 djm 1957: tag != NULL ? tag : "", tag != NULL ? ": " : "",
1.220 djm 1958: ssh->state->server_side ? "from" : "to",
1959: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), ssh_err(r));
1.205 djm 1960: }
1.1 deraadt 1961: }
1962:
1.16 markus 1963: /*
1964: * Logs the error plus constructs and sends a disconnect packet, closes the
1965: * connection, and exits. This function never returns. The error message
1966: * should not contain a newline. The length of the formatted message must
1967: * not exceed 1024 bytes.
1968: */
1.2 provos 1969: void
1.201 markus 1970: ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1971: {
1.14 markus 1972: char buf[1024];
1973: va_list args;
1974: static int disconnecting = 0;
1.201 markus 1975: int r;
1.97 deraadt 1976:
1.14 markus 1977: if (disconnecting) /* Guard against recursive invocations. */
1978: fatal("packet_disconnect called recursively.");
1979: disconnecting = 1;
1980:
1.16 markus 1981: /*
1982: * Format the message. Note that the caller must make sure the
1983: * message is of limited size.
1984: */
1.14 markus 1985: va_start(args, fmt);
1986: vsnprintf(buf, sizeof(buf), fmt, args);
1987: va_end(args);
1988:
1.99 markus 1989: /* Display the error locally */
1.106 itojun 1990: logit("Disconnecting: %.100s", buf);
1.99 markus 1991:
1.205 djm 1992: /*
1993: * Send the disconnect message to the other side, and wait
1994: * for it to get sent.
1995: */
1996: if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1997: sshpkt_fatal(ssh, __func__, r);
1998:
1999: if ((r = ssh_packet_write_wait(ssh)) != 0)
2000: sshpkt_fatal(ssh, __func__, r);
1.14 markus 2001:
2002: /* Close the connection. */
1.201 markus 2003: ssh_packet_close(ssh);
1.112 markus 2004: cleanup_exit(255);
1.1 deraadt 2005: }
2006:
1.205 djm 2007: /*
2008: * Checks if there is any buffered output, and tries to write some of
2009: * the output.
2010: */
2011: int
1.201 markus 2012: ssh_packet_write_poll(struct ssh *ssh)
1.1 deraadt 2013: {
1.201 markus 2014: struct session_state *state = ssh->state;
2015: int len = sshbuf_len(state->output);
2016: int cont, r;
1.97 deraadt 2017:
1.14 markus 2018: if (len > 0) {
1.163 andreas 2019: cont = 0;
1.201 markus 2020: len = roaming_write(state->connection_out,
2021: sshbuf_ptr(state->output), len, &cont);
1.156 djm 2022: if (len == -1) {
2023: if (errno == EINTR || errno == EAGAIN)
1.205 djm 2024: return 0;
2025: return SSH_ERR_SYSTEM_ERROR;
1.14 markus 2026: }
1.163 andreas 2027: if (len == 0 && !cont)
1.205 djm 2028: return SSH_ERR_CONN_CLOSED;
1.201 markus 2029: if ((r = sshbuf_consume(state->output, len)) != 0)
1.205 djm 2030: return r;
1.14 markus 2031: }
1.205 djm 2032: return 0;
1.1 deraadt 2033: }
2034:
1.16 markus 2035: /*
2036: * Calls packet_write_poll repeatedly until all pending output data has been
2037: * written.
2038: */
1.205 djm 2039: int
1.201 markus 2040: ssh_packet_write_wait(struct ssh *ssh)
1.1 deraadt 2041: {
1.56 millert 2042: fd_set *setp;
1.205 djm 2043: int ret, r, ms_remain = 0;
1.154 dtucker 2044: struct timeval start, timeout, *timeoutp = NULL;
1.201 markus 2045: struct session_state *state = ssh->state;
1.56 millert 2046:
1.214 deraadt 2047: setp = calloc(howmany(state->connection_out + 1,
1.161 andreas 2048: NFDBITS), sizeof(fd_mask));
1.201 markus 2049: if (setp == NULL)
1.205 djm 2050: return SSH_ERR_ALLOC_FAIL;
1.216 gsoares 2051: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2052: free(setp);
1.215 djm 2053: return r;
1.216 gsoares 2054: }
1.201 markus 2055: while (ssh_packet_have_data_to_write(ssh)) {
2056: memset(setp, 0, howmany(state->connection_out + 1,
1.161 andreas 2057: NFDBITS) * sizeof(fd_mask));
1.201 markus 2058: FD_SET(state->connection_out, setp);
1.154 dtucker 2059:
1.201 markus 2060: if (state->packet_timeout_ms > 0) {
2061: ms_remain = state->packet_timeout_ms;
1.154 dtucker 2062: timeoutp = &timeout;
2063: }
2064: for (;;) {
1.201 markus 2065: if (state->packet_timeout_ms != -1) {
1.154 dtucker 2066: ms_to_timeval(&timeout, ms_remain);
2067: gettimeofday(&start, NULL);
2068: }
1.201 markus 2069: if ((ret = select(state->connection_out + 1,
1.161 andreas 2070: NULL, setp, NULL, timeoutp)) >= 0)
1.154 dtucker 2071: break;
1.161 andreas 2072: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 2073: break;
1.201 markus 2074: if (state->packet_timeout_ms == -1)
1.154 dtucker 2075: continue;
2076: ms_subtract_diff(&start, &ms_remain);
2077: if (ms_remain <= 0) {
2078: ret = 0;
2079: break;
2080: }
2081: }
2082: if (ret == 0) {
1.205 djm 2083: free(setp);
2084: return SSH_ERR_CONN_TIMEOUT;
2085: }
2086: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2087: free(setp);
2088: return r;
1.154 dtucker 2089: }
1.14 markus 2090: }
1.186 djm 2091: free(setp);
1.205 djm 2092: return 0;
1.1 deraadt 2093: }
2094:
2095: /* Returns true if there is buffered data to write to the connection. */
2096:
1.2 provos 2097: int
1.201 markus 2098: ssh_packet_have_data_to_write(struct ssh *ssh)
1.1 deraadt 2099: {
1.201 markus 2100: return sshbuf_len(ssh->state->output) != 0;
1.1 deraadt 2101: }
2102:
2103: /* Returns true if there is not too much data to write to the connection. */
2104:
1.2 provos 2105: int
1.201 markus 2106: ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1.1 deraadt 2107: {
1.201 markus 2108: if (ssh->state->interactive_mode)
2109: return sshbuf_len(ssh->state->output) < 16384;
1.14 markus 2110: else
1.201 markus 2111: return sshbuf_len(ssh->state->output) < 128 * 1024;
1.1 deraadt 2112: }
2113:
1.201 markus 2114: void
2115: ssh_packet_set_tos(struct ssh *ssh, int tos)
1.101 markus 2116: {
1.201 markus 2117: if (!ssh_packet_connection_is_on_socket(ssh))
1.101 markus 2118: return;
1.201 markus 2119: switch (ssh_packet_connection_af(ssh)) {
1.173 djm 2120: case AF_INET:
2121: debug3("%s: set IP_TOS 0x%02x", __func__, tos);
1.201 markus 2122: if (setsockopt(ssh->state->connection_in,
1.173 djm 2123: IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2124: error("setsockopt IP_TOS %d: %.100s:",
2125: tos, strerror(errno));
2126: break;
2127: case AF_INET6:
2128: debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
1.201 markus 2129: if (setsockopt(ssh->state->connection_in,
1.173 djm 2130: IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2131: error("setsockopt IPV6_TCLASS %d: %.100s:",
2132: tos, strerror(errno));
2133: break;
2134: }
1.101 markus 2135: }
2136:
1.1 deraadt 2137: /* Informs that the current session is interactive. Sets IP flags for that. */
2138:
1.2 provos 2139: void
1.201 markus 2140: ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
1.1 deraadt 2141: {
1.201 markus 2142: struct session_state *state = ssh->state;
2143:
2144: if (state->set_interactive_called)
1.43 markus 2145: return;
1.201 markus 2146: state->set_interactive_called = 1;
1.1 deraadt 2147:
1.14 markus 2148: /* Record that we are in interactive mode. */
1.201 markus 2149: state->interactive_mode = interactive;
1.1 deraadt 2150:
1.19 markus 2151: /* Only set socket options if using a socket. */
1.201 markus 2152: if (!ssh_packet_connection_is_on_socket(ssh))
1.14 markus 2153: return;
1.201 markus 2154: set_nodelay(state->connection_in);
2155: ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2156: qos_bulk);
1.1 deraadt 2157: }
2158:
2159: /* Returns true if the current connection is interactive. */
2160:
1.2 provos 2161: int
1.201 markus 2162: ssh_packet_is_interactive(struct ssh *ssh)
1.1 deraadt 2163: {
1.201 markus 2164: return ssh->state->interactive_mode;
1.12 markus 2165: }
2166:
1.113 deraadt 2167: int
1.201 markus 2168: ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
1.12 markus 2169: {
1.201 markus 2170: struct session_state *state = ssh->state;
2171:
2172: if (state->set_maxsize_called) {
1.106 itojun 2173: logit("packet_set_maxsize: called twice: old %d new %d",
1.201 markus 2174: state->max_packet_size, s);
1.14 markus 2175: return -1;
2176: }
2177: if (s < 4 * 1024 || s > 1024 * 1024) {
1.106 itojun 2178: logit("packet_set_maxsize: bad size %d", s);
1.14 markus 2179: return -1;
2180: }
1.201 markus 2181: state->set_maxsize_called = 1;
1.66 markus 2182: debug("packet_set_maxsize: setting to %d", s);
1.201 markus 2183: state->max_packet_size = s;
1.14 markus 2184: return s;
1.53 markus 2185: }
2186:
1.161 andreas 2187: int
1.201 markus 2188: ssh_packet_inc_alive_timeouts(struct ssh *ssh)
1.161 andreas 2189: {
1.201 markus 2190: return ++ssh->state->keep_alive_timeouts;
1.161 andreas 2191: }
2192:
2193: void
1.201 markus 2194: ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
1.161 andreas 2195: {
1.201 markus 2196: ssh->state->keep_alive_timeouts = ka;
1.161 andreas 2197: }
2198:
2199: u_int
1.201 markus 2200: ssh_packet_get_maxsize(struct ssh *ssh)
1.71 markus 2201: {
1.201 markus 2202: return ssh->state->max_packet_size;
1.71 markus 2203: }
2204:
1.53 markus 2205: /*
2206: * 9.2. Ignored Data Message
1.61 markus 2207: *
1.53 markus 2208: * byte SSH_MSG_IGNORE
2209: * string data
1.61 markus 2210: *
1.53 markus 2211: * All implementations MUST understand (and ignore) this message at any
2212: * time (after receiving the protocol version). No implementation is
2213: * required to send them. This message can be used as an additional
2214: * protection measure against advanced traffic analysis techniques.
2215: */
1.54 markus 2216: void
1.201 markus 2217: ssh_packet_send_ignore(struct ssh *ssh, int nbytes)
1.54 markus 2218: {
1.115 avsm 2219: u_int32_t rnd = 0;
1.201 markus 2220: int r, i;
1.54 markus 2221:
1.201 markus 2222: if ((r = sshpkt_start(ssh, compat20 ?
2223: SSH2_MSG_IGNORE : SSH_MSG_IGNORE)) != 0 ||
2224: (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2225: fatal("%s: %s", __func__, ssh_err(r));
1.75 deraadt 2226: for (i = 0; i < nbytes; i++) {
1.53 markus 2227: if (i % 4 == 0)
1.115 avsm 2228: rnd = arc4random();
1.201 markus 2229: if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2230: fatal("%s: %s", __func__, ssh_err(r));
1.115 avsm 2231: rnd >>= 8;
1.53 markus 2232: }
1.105 markus 2233: }
2234:
1.113 deraadt 2235: #define MAX_PACKETS (1U<<31)
1.105 markus 2236: int
1.201 markus 2237: ssh_packet_need_rekeying(struct ssh *ssh)
1.105 markus 2238: {
1.201 markus 2239: struct session_state *state = ssh->state;
2240:
2241: if (ssh->compat & SSH_BUG_NOREKEY)
1.105 markus 2242: return 0;
2243: return
1.201 markus 2244: (state->p_send.packets > MAX_PACKETS) ||
2245: (state->p_read.packets > MAX_PACKETS) ||
2246: (state->max_blocks_out &&
2247: (state->p_send.blocks > state->max_blocks_out)) ||
2248: (state->max_blocks_in &&
2249: (state->p_read.blocks > state->max_blocks_in)) ||
2250: (state->rekey_interval != 0 && state->rekey_time +
2251: state->rekey_interval <= monotime());
1.105 markus 2252: }
2253:
2254: void
1.201 markus 2255: ssh_packet_set_rekey_limits(struct ssh *ssh, u_int32_t bytes, time_t seconds)
1.105 markus 2256: {
1.184 dtucker 2257: debug3("rekey after %lld bytes, %d seconds", (long long)bytes,
2258: (int)seconds);
1.201 markus 2259: ssh->state->rekey_limit = bytes;
2260: ssh->state->rekey_interval = seconds;
1.184 dtucker 2261: }
2262:
2263: time_t
1.201 markus 2264: ssh_packet_get_rekey_timeout(struct ssh *ssh)
1.184 dtucker 2265: {
2266: time_t seconds;
2267:
1.201 markus 2268: seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
1.187 dtucker 2269: monotime();
1.185 dtucker 2270: return (seconds <= 0 ? 1 : seconds);
1.118 markus 2271: }
2272:
2273: void
1.201 markus 2274: ssh_packet_set_server(struct ssh *ssh)
1.118 markus 2275: {
1.201 markus 2276: ssh->state->server_side = 1;
1.118 markus 2277: }
2278:
2279: void
1.201 markus 2280: ssh_packet_set_authenticated(struct ssh *ssh)
1.118 markus 2281: {
1.201 markus 2282: ssh->state->after_authentication = 1;
1.161 andreas 2283: }
2284:
2285: void *
1.201 markus 2286: ssh_packet_get_input(struct ssh *ssh)
1.161 andreas 2287: {
1.201 markus 2288: return (void *)ssh->state->input;
1.161 andreas 2289: }
2290:
2291: void *
1.201 markus 2292: ssh_packet_get_output(struct ssh *ssh)
1.161 andreas 2293: {
1.201 markus 2294: return (void *)ssh->state->output;
1.166 andreas 2295: }
2296:
1.201 markus 2297: /* XXX TODO update roaming to new API (does not work anyway) */
1.166 andreas 2298: /*
2299: * Save the state for the real connection, and use a separate state when
2300: * resuming a suspended connection.
2301: */
2302: void
1.201 markus 2303: ssh_packet_backup_state(struct ssh *ssh,
2304: struct ssh *backup_state)
1.166 andreas 2305: {
1.201 markus 2306: struct ssh *tmp;
1.166 andreas 2307:
1.201 markus 2308: close(ssh->state->connection_in);
2309: ssh->state->connection_in = -1;
2310: close(ssh->state->connection_out);
2311: ssh->state->connection_out = -1;
1.166 andreas 2312: if (backup_state)
2313: tmp = backup_state;
2314: else
1.201 markus 2315: tmp = ssh_alloc_session_state();
2316: backup_state = ssh;
2317: ssh = tmp;
1.166 andreas 2318: }
2319:
1.201 markus 2320: /* XXX FIXME FIXME FIXME */
1.166 andreas 2321: /*
2322: * Swap in the old state when resuming a connecion.
2323: */
2324: void
1.201 markus 2325: ssh_packet_restore_state(struct ssh *ssh,
2326: struct ssh *backup_state)
1.166 andreas 2327: {
1.201 markus 2328: struct ssh *tmp;
1.166 andreas 2329: u_int len;
1.201 markus 2330: int r;
1.166 andreas 2331:
2332: tmp = backup_state;
1.201 markus 2333: backup_state = ssh;
2334: ssh = tmp;
2335: ssh->state->connection_in = backup_state->state->connection_in;
2336: backup_state->state->connection_in = -1;
2337: ssh->state->connection_out = backup_state->state->connection_out;
2338: backup_state->state->connection_out = -1;
2339: len = sshbuf_len(backup_state->state->input);
1.166 andreas 2340: if (len > 0) {
1.201 markus 2341: if ((r = sshbuf_putb(ssh->state->input,
2342: backup_state->state->input)) != 0)
2343: fatal("%s: %s", __func__, ssh_err(r));
2344: sshbuf_reset(backup_state->state->input);
1.166 andreas 2345: add_recv_bytes(len);
1.196 markus 2346: }
2347: }
2348:
2349: /* Reset after_authentication and reset compression in post-auth privsep */
1.201 markus 2350: static int
2351: ssh_packet_set_postauth(struct ssh *ssh)
1.196 markus 2352: {
1.201 markus 2353: struct sshcomp *comp;
2354: int r, mode;
1.196 markus 2355:
2356: debug("%s: called", __func__);
2357: /* This was set in net child, but is not visible in user child */
1.201 markus 2358: ssh->state->after_authentication = 1;
2359: ssh->state->rekeying = 0;
1.196 markus 2360: for (mode = 0; mode < MODE_MAX; mode++) {
1.201 markus 2361: if (ssh->state->newkeys[mode] == NULL)
1.196 markus 2362: continue;
1.201 markus 2363: comp = &ssh->state->newkeys[mode]->comp;
2364: if (comp && comp->enabled &&
2365: (r = ssh_packet_init_compression(ssh)) != 0)
2366: return r;
2367: }
2368: return 0;
2369: }
2370:
2371: /* Packet state (de-)serialization for privsep */
2372:
2373: /* turn kex into a blob for packet state serialization */
2374: static int
2375: kex_to_blob(struct sshbuf *m, struct kex *kex)
2376: {
2377: int r;
2378:
2379: if ((r = sshbuf_put_string(m, kex->session_id,
2380: kex->session_id_len)) != 0 ||
2381: (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2382: (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2383: (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2384: (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2385: (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2386: (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2387: (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2388: (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2389: return r;
2390: return 0;
2391: }
2392:
2393: /* turn key exchange results into a blob for packet state serialization */
2394: static int
2395: newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2396: {
2397: struct sshbuf *b;
2398: struct sshcipher_ctx *cc;
2399: struct sshcomp *comp;
2400: struct sshenc *enc;
2401: struct sshmac *mac;
2402: struct newkeys *newkey;
2403: int r;
2404:
2405: if ((newkey = ssh->state->newkeys[mode]) == NULL)
2406: return SSH_ERR_INTERNAL_ERROR;
2407: enc = &newkey->enc;
2408: mac = &newkey->mac;
2409: comp = &newkey->comp;
2410: cc = (mode == MODE_OUT) ? &ssh->state->send_context :
2411: &ssh->state->receive_context;
2412: if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2413: return r;
2414: if ((b = sshbuf_new()) == NULL)
2415: return SSH_ERR_ALLOC_FAIL;
2416: /* The cipher struct is constant and shared, you export pointer */
2417: if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2418: (r = sshbuf_put(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2419: (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2420: (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2421: (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2422: (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2423: goto out;
2424: if (cipher_authlen(enc->cipher) == 0) {
2425: if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2426: (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2427: (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2428: goto out;
2429: }
2430: if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2431: (r = sshbuf_put_u32(b, comp->enabled)) != 0 ||
2432: (r = sshbuf_put_cstring(b, comp->name)) != 0)
2433: goto out;
2434: r = sshbuf_put_stringb(m, b);
2435: out:
1.221 ! mmcc 2436: sshbuf_free(b);
1.201 markus 2437: return r;
2438: }
2439:
2440: /* serialize packet state into a blob */
2441: int
2442: ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2443: {
2444: struct session_state *state = ssh->state;
2445: u_char *p;
2446: size_t slen, rlen;
2447: int r, ssh1cipher;
2448:
2449: if (!compat20) {
2450: ssh1cipher = cipher_get_number(state->receive_context.cipher);
2451: slen = cipher_get_keyiv_len(&state->send_context);
2452: rlen = cipher_get_keyiv_len(&state->receive_context);
2453: if ((r = sshbuf_put_u32(m, state->remote_protocol_flags)) != 0 ||
2454: (r = sshbuf_put_u32(m, ssh1cipher)) != 0 ||
2455: (r = sshbuf_put_string(m, state->ssh1_key, state->ssh1_keylen)) != 0 ||
2456: (r = sshbuf_put_u32(m, slen)) != 0 ||
2457: (r = sshbuf_reserve(m, slen, &p)) != 0 ||
2458: (r = cipher_get_keyiv(&state->send_context, p, slen)) != 0 ||
2459: (r = sshbuf_put_u32(m, rlen)) != 0 ||
2460: (r = sshbuf_reserve(m, rlen, &p)) != 0 ||
2461: (r = cipher_get_keyiv(&state->receive_context, p, rlen)) != 0)
2462: return r;
2463: } else {
2464: if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2465: (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2466: (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
1.208 markus 2467: (r = sshbuf_put_u32(m, state->rekey_limit)) != 0 ||
2468: (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
1.201 markus 2469: (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2470: (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2471: (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2472: (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2473: (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2474: (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2475: (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2476: (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0)
2477: return r;
2478: }
2479:
2480: slen = cipher_get_keycontext(&state->send_context, NULL);
2481: rlen = cipher_get_keycontext(&state->receive_context, NULL);
2482: if ((r = sshbuf_put_u32(m, slen)) != 0 ||
2483: (r = sshbuf_reserve(m, slen, &p)) != 0)
2484: return r;
2485: if (cipher_get_keycontext(&state->send_context, p) != (int)slen)
2486: return SSH_ERR_INTERNAL_ERROR;
2487: if ((r = sshbuf_put_u32(m, rlen)) != 0 ||
2488: (r = sshbuf_reserve(m, rlen, &p)) != 0)
2489: return r;
2490: if (cipher_get_keycontext(&state->receive_context, p) != (int)rlen)
2491: return SSH_ERR_INTERNAL_ERROR;
2492:
2493: if ((r = ssh_packet_get_compress_state(m, ssh)) != 0 ||
2494: (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2495: (r = sshbuf_put_stringb(m, state->output)) != 0)
2496: return r;
2497:
2498: if (compat20) {
2499: if ((r = sshbuf_put_u64(m, get_sent_bytes())) != 0 ||
2500: (r = sshbuf_put_u64(m, get_recv_bytes())) != 0)
2501: return r;
2502: }
2503: return 0;
2504: }
2505:
2506: /* restore key exchange results from blob for packet state de-serialization */
2507: static int
2508: newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2509: {
2510: struct sshbuf *b = NULL;
2511: struct sshcomp *comp;
2512: struct sshenc *enc;
2513: struct sshmac *mac;
2514: struct newkeys *newkey = NULL;
2515: size_t keylen, ivlen, maclen;
2516: int r;
2517:
2518: if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2519: r = SSH_ERR_ALLOC_FAIL;
2520: goto out;
2521: }
2522: if ((r = sshbuf_froms(m, &b)) != 0)
2523: goto out;
2524: #ifdef DEBUG_PK
2525: sshbuf_dump(b, stderr);
2526: #endif
2527: enc = &newkey->enc;
2528: mac = &newkey->mac;
2529: comp = &newkey->comp;
2530:
2531: if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2532: (r = sshbuf_get(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2533: (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2534: (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2535: (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2536: (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2537: goto out;
2538: if (cipher_authlen(enc->cipher) == 0) {
2539: if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2540: goto out;
2541: if ((r = mac_setup(mac, mac->name)) != 0)
2542: goto out;
2543: if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2544: (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2545: goto out;
2546: if (maclen > mac->key_len) {
2547: r = SSH_ERR_INVALID_FORMAT;
2548: goto out;
2549: }
2550: mac->key_len = maclen;
2551: }
2552: if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2553: (r = sshbuf_get_u32(b, (u_int *)&comp->enabled)) != 0 ||
2554: (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2555: goto out;
2556: if (enc->name == NULL ||
2557: cipher_by_name(enc->name) != enc->cipher) {
2558: r = SSH_ERR_INVALID_FORMAT;
2559: goto out;
2560: }
2561: if (sshbuf_len(b) != 0) {
2562: r = SSH_ERR_INVALID_FORMAT;
2563: goto out;
2564: }
2565: enc->key_len = keylen;
2566: enc->iv_len = ivlen;
2567: ssh->kex->newkeys[mode] = newkey;
2568: newkey = NULL;
2569: r = 0;
2570: out:
1.219 mmcc 2571: free(newkey);
1.221 ! mmcc 2572: sshbuf_free(b);
1.201 markus 2573: return r;
2574: }
2575:
2576: /* restore kex from blob for packet state de-serialization */
2577: static int
2578: kex_from_blob(struct sshbuf *m, struct kex **kexp)
2579: {
2580: struct kex *kex;
2581: int r;
2582:
2583: if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2584: (kex->my = sshbuf_new()) == NULL ||
2585: (kex->peer = sshbuf_new()) == NULL) {
2586: r = SSH_ERR_ALLOC_FAIL;
2587: goto out;
2588: }
2589: if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2590: (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2591: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2592: (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2593: (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2594: (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2595: (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2596: (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2597: (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2598: goto out;
2599: kex->server = 1;
2600: kex->done = 1;
2601: r = 0;
2602: out:
2603: if (r != 0 || kexp == NULL) {
2604: if (kex != NULL) {
1.221 ! mmcc 2605: sshbuf_free(kex->my);
! 2606: sshbuf_free(kex->peer);
1.201 markus 2607: free(kex);
2608: }
2609: if (kexp != NULL)
2610: *kexp = NULL;
2611: } else {
2612: *kexp = kex;
2613: }
2614: return r;
2615: }
2616:
2617: /*
2618: * Restore packet state from content of blob 'm' (de-serialization).
2619: * Note that 'm' will be partially consumed on parsing or any other errors.
2620: */
2621: int
2622: ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2623: {
2624: struct session_state *state = ssh->state;
2625: const u_char *ssh1key, *ivin, *ivout, *keyin, *keyout, *input, *output;
2626: size_t ssh1keylen, rlen, slen, ilen, olen;
2627: int r;
2628: u_int ssh1cipher = 0;
2629: u_int64_t sent_bytes = 0, recv_bytes = 0;
2630:
2631: if (!compat20) {
2632: if ((r = sshbuf_get_u32(m, &state->remote_protocol_flags)) != 0 ||
2633: (r = sshbuf_get_u32(m, &ssh1cipher)) != 0 ||
2634: (r = sshbuf_get_string_direct(m, &ssh1key, &ssh1keylen)) != 0 ||
2635: (r = sshbuf_get_string_direct(m, &ivout, &slen)) != 0 ||
2636: (r = sshbuf_get_string_direct(m, &ivin, &rlen)) != 0)
2637: return r;
2638: if (ssh1cipher > INT_MAX)
2639: return SSH_ERR_KEY_UNKNOWN_CIPHER;
2640: ssh_packet_set_encryption_key(ssh, ssh1key, ssh1keylen,
2641: (int)ssh1cipher);
2642: if (cipher_get_keyiv_len(&state->send_context) != (int)slen ||
2643: cipher_get_keyiv_len(&state->receive_context) != (int)rlen)
2644: return SSH_ERR_INVALID_FORMAT;
2645: if ((r = cipher_set_keyiv(&state->send_context, ivout)) != 0 ||
2646: (r = cipher_set_keyiv(&state->receive_context, ivin)) != 0)
2647: return r;
2648: } else {
2649: if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2650: (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2651: (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
1.208 markus 2652: (r = sshbuf_get_u32(m, &state->rekey_limit)) != 0 ||
2653: (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
1.201 markus 2654: (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2655: (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2656: (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2657: (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2658: (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2659: (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2660: (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2661: (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2662: return r;
1.208 markus 2663: /*
2664: * We set the time here so that in post-auth privsep slave we
2665: * count from the completion of the authentication.
2666: */
2667: state->rekey_time = monotime();
1.201 markus 2668: /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2669: if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2670: (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2671: return r;
2672: }
2673: if ((r = sshbuf_get_string_direct(m, &keyout, &slen)) != 0 ||
2674: (r = sshbuf_get_string_direct(m, &keyin, &rlen)) != 0)
2675: return r;
2676: if (cipher_get_keycontext(&state->send_context, NULL) != (int)slen ||
2677: cipher_get_keycontext(&state->receive_context, NULL) != (int)rlen)
2678: return SSH_ERR_INVALID_FORMAT;
2679: cipher_set_keycontext(&state->send_context, keyout);
2680: cipher_set_keycontext(&state->receive_context, keyin);
2681:
2682: if ((r = ssh_packet_set_compress_state(ssh, m)) != 0 ||
2683: (r = ssh_packet_set_postauth(ssh)) != 0)
2684: return r;
2685:
2686: sshbuf_reset(state->input);
2687: sshbuf_reset(state->output);
2688: if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2689: (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2690: (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2691: (r = sshbuf_put(state->output, output, olen)) != 0)
2692: return r;
2693:
2694: if (compat20) {
2695: if ((r = sshbuf_get_u64(m, &sent_bytes)) != 0 ||
2696: (r = sshbuf_get_u64(m, &recv_bytes)) != 0)
2697: return r;
2698: roam_set_bytes(sent_bytes, recv_bytes);
2699: }
2700: if (sshbuf_len(m))
2701: return SSH_ERR_INVALID_FORMAT;
2702: debug3("%s: done", __func__);
2703: return 0;
2704: }
2705:
2706: /* NEW API */
2707:
2708: /* put data to the outgoing packet */
2709:
2710: int
2711: sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2712: {
2713: return sshbuf_put(ssh->state->outgoing_packet, v, len);
2714: }
2715:
2716: int
2717: sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2718: {
2719: return sshbuf_putb(ssh->state->outgoing_packet, b);
2720: }
2721:
2722: int
2723: sshpkt_put_u8(struct ssh *ssh, u_char val)
2724: {
2725: return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2726: }
2727:
2728: int
2729: sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2730: {
2731: return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2732: }
2733:
2734: int
2735: sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2736: {
2737: return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2738: }
2739:
2740: int
2741: sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2742: {
2743: return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2744: }
2745:
2746: int
2747: sshpkt_put_cstring(struct ssh *ssh, const void *v)
2748: {
2749: return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2750: }
2751:
2752: int
2753: sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2754: {
2755: return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2756: }
2757:
1.211 djm 2758: #ifdef WITH_OPENSSL
1.201 markus 2759: int
2760: sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2761: {
2762: return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2763: }
2764:
1.211 djm 2765: #ifdef WITH_SSH1
1.201 markus 2766: int
2767: sshpkt_put_bignum1(struct ssh *ssh, const BIGNUM *v)
2768: {
2769: return sshbuf_put_bignum1(ssh->state->outgoing_packet, v);
2770: }
1.211 djm 2771: #endif /* WITH_SSH1 */
1.201 markus 2772:
2773: int
2774: sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2775: {
2776: return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2777: }
1.211 djm 2778: #endif /* WITH_OPENSSL */
1.201 markus 2779:
2780: /* fetch data from the incoming packet */
2781:
2782: int
2783: sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2784: {
2785: return sshbuf_get(ssh->state->incoming_packet, valp, len);
2786: }
2787:
2788: int
2789: sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2790: {
2791: return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2792: }
2793:
2794: int
2795: sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2796: {
2797: return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2798: }
2799:
2800: int
2801: sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2802: {
2803: return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2804: }
2805:
2806: int
2807: sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2808: {
2809: return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2810: }
2811:
2812: int
2813: sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2814: {
2815: return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2816: }
2817:
2818: int
2819: sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2820: {
2821: return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2822: }
2823:
1.211 djm 2824: #ifdef WITH_OPENSSL
1.201 markus 2825: int
2826: sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2827: {
2828: return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2829: }
2830:
1.211 djm 2831: #ifdef WITH_SSH1
1.201 markus 2832: int
2833: sshpkt_get_bignum1(struct ssh *ssh, BIGNUM *v)
2834: {
2835: return sshbuf_get_bignum1(ssh->state->incoming_packet, v);
2836: }
1.211 djm 2837: #endif /* WITH_SSH1 */
1.201 markus 2838:
2839: int
2840: sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2841: {
2842: return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2843: }
1.211 djm 2844: #endif /* WITH_OPENSSL */
1.201 markus 2845:
2846: int
2847: sshpkt_get_end(struct ssh *ssh)
2848: {
2849: if (sshbuf_len(ssh->state->incoming_packet) > 0)
2850: return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2851: return 0;
2852: }
2853:
2854: const u_char *
2855: sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2856: {
2857: if (lenp != NULL)
2858: *lenp = sshbuf_len(ssh->state->incoming_packet);
2859: return sshbuf_ptr(ssh->state->incoming_packet);
2860: }
2861:
2862: /* start a new packet */
2863:
2864: int
2865: sshpkt_start(struct ssh *ssh, u_char type)
2866: {
2867: u_char buf[9];
2868: int len;
2869:
2870: DBG(debug("packet_start[%d]", type));
2871: len = compat20 ? 6 : 9;
2872: memset(buf, 0, len - 1);
2873: buf[len - 1] = type;
2874: sshbuf_reset(ssh->state->outgoing_packet);
2875: return sshbuf_put(ssh->state->outgoing_packet, buf, len);
2876: }
2877:
2878: /* send it */
2879:
2880: int
2881: sshpkt_send(struct ssh *ssh)
2882: {
2883: if (compat20)
2884: return ssh_packet_send2(ssh);
2885: else
2886: return ssh_packet_send1(ssh);
2887: }
2888:
2889: int
2890: sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2891: {
2892: char buf[1024];
2893: va_list args;
2894: int r;
2895:
2896: va_start(args, fmt);
2897: vsnprintf(buf, sizeof(buf), fmt, args);
2898: va_end(args);
2899:
2900: if (compat20) {
2901: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2902: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2903: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2904: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2905: (r = sshpkt_send(ssh)) != 0)
2906: return r;
2907: } else {
2908: if ((r = sshpkt_start(ssh, SSH_MSG_DISCONNECT)) != 0 ||
2909: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2910: (r = sshpkt_send(ssh)) != 0)
2911: return r;
1.166 andreas 2912: }
1.201 markus 2913: return 0;
2914: }
2915:
2916: /* roundup current message to pad bytes */
2917: int
2918: sshpkt_add_padding(struct ssh *ssh, u_char pad)
2919: {
2920: ssh->state->extra_pad = pad;
2921: return 0;
1.1 deraadt 2922: }
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