Annotation of src/usr.bin/ssh/packet.c, Revision 1.218
1.218 ! markus 1: /* $OpenBSD: packet.c,v 1.217 2015/11/08 21:59:11 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: }
1.201 markus 335: logit("Finished discarding for %.200s", ssh_remote_ipaddr(ssh));
336: return SSH_ERR_MAC_INVALID;
1.159 markus 337: }
338:
1.201 markus 339: static int
340: ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
341: struct sshmac *mac, u_int packet_length, u_int discard)
1.159 markus 342: {
1.201 markus 343: struct session_state *state = ssh->state;
344: int r;
345:
346: if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
347: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
348: return r;
349: return SSH_ERR_MAC_INVALID;
350: }
1.159 markus 351: if (packet_length != PACKET_MAX_SIZE && mac && mac->enabled)
1.201 markus 352: state->packet_discard_mac = mac;
353: if (sshbuf_len(state->input) >= discard &&
354: (r = ssh_packet_stop_discard(ssh)) != 0)
355: return r;
356: state->packet_discard = discard - sshbuf_len(state->input);
357: return 0;
1.159 markus 358: }
359:
1.19 markus 360: /* Returns 1 if remote host is connected via socket, 0 if not. */
361:
362: int
1.201 markus 363: ssh_packet_connection_is_on_socket(struct ssh *ssh)
1.19 markus 364: {
1.201 markus 365: struct session_state *state = ssh->state;
1.19 markus 366: struct sockaddr_storage from, to;
367: socklen_t fromlen, tolen;
368:
369: /* filedescriptors in and out are the same, so it's a socket */
1.201 markus 370: if (state->connection_in == state->connection_out)
1.19 markus 371: return 1;
372: fromlen = sizeof(from);
373: memset(&from, 0, sizeof(from));
1.201 markus 374: if (getpeername(state->connection_in, (struct sockaddr *)&from,
1.161 andreas 375: &fromlen) < 0)
1.19 markus 376: return 0;
377: tolen = sizeof(to);
378: memset(&to, 0, sizeof(to));
1.201 markus 379: if (getpeername(state->connection_out, (struct sockaddr *)&to,
1.161 andreas 380: &tolen) < 0)
1.19 markus 381: return 0;
382: if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
383: return 0;
384: if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
385: return 0;
386: return 1;
387: }
388:
1.91 markus 389: void
1.201 markus 390: ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
1.91 markus 391: {
1.201 markus 392: if (ibytes)
393: *ibytes = ssh->state->p_read.bytes;
394: if (obytes)
395: *obytes = ssh->state->p_send.bytes;
1.91 markus 396: }
1.125 deraadt 397:
1.91 markus 398: int
1.201 markus 399: ssh_packet_connection_af(struct ssh *ssh)
1.19 markus 400: {
401: struct sockaddr_storage to;
1.21 deraadt 402: socklen_t tolen = sizeof(to);
1.19 markus 403:
404: memset(&to, 0, sizeof(to));
1.201 markus 405: if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
1.161 andreas 406: &tolen) < 0)
1.19 markus 407: return 0;
1.173 djm 408: return to.ss_family;
1.19 markus 409: }
410:
1.1 deraadt 411: /* Sets the connection into non-blocking mode. */
412:
1.2 provos 413: void
1.201 markus 414: ssh_packet_set_nonblocking(struct ssh *ssh)
1.1 deraadt 415: {
1.14 markus 416: /* Set the socket into non-blocking mode. */
1.201 markus 417: set_nonblock(ssh->state->connection_in);
1.14 markus 418:
1.201 markus 419: if (ssh->state->connection_out != ssh->state->connection_in)
420: set_nonblock(ssh->state->connection_out);
1.1 deraadt 421: }
422:
423: /* Returns the socket used for reading. */
424:
1.2 provos 425: int
1.201 markus 426: ssh_packet_get_connection_in(struct ssh *ssh)
1.1 deraadt 427: {
1.201 markus 428: return ssh->state->connection_in;
1.1 deraadt 429: }
430:
431: /* Returns the descriptor used for writing. */
432:
1.2 provos 433: int
1.201 markus 434: ssh_packet_get_connection_out(struct ssh *ssh)
1.1 deraadt 435: {
1.201 markus 436: return ssh->state->connection_out;
437: }
438:
439: /*
440: * Returns the IP-address of the remote host as a string. The returned
441: * string must not be freed.
442: */
443:
444: const char *
445: ssh_remote_ipaddr(struct ssh *ssh)
446: {
447: /* Check whether we have cached the ipaddr. */
448: if (ssh->remote_ipaddr == NULL)
449: ssh->remote_ipaddr = ssh_packet_connection_is_on_socket(ssh) ?
450: get_peer_ipaddr(ssh->state->connection_in) :
451: strdup("UNKNOWN");
452: if (ssh->remote_ipaddr == NULL)
453: return "UNKNOWN";
454: return ssh->remote_ipaddr;
1.1 deraadt 455: }
456:
457: /* Closes the connection and clears and frees internal data structures. */
458:
1.2 provos 459: void
1.201 markus 460: ssh_packet_close(struct ssh *ssh)
1.1 deraadt 461: {
1.201 markus 462: struct session_state *state = ssh->state;
463: int r;
464: u_int mode;
465:
466: if (!state->initialized)
1.14 markus 467: return;
1.201 markus 468: state->initialized = 0;
469: if (state->connection_in == state->connection_out) {
470: shutdown(state->connection_out, SHUT_RDWR);
471: close(state->connection_out);
1.14 markus 472: } else {
1.201 markus 473: close(state->connection_in);
474: close(state->connection_out);
1.14 markus 475: }
1.201 markus 476: sshbuf_free(state->input);
477: sshbuf_free(state->output);
478: sshbuf_free(state->outgoing_packet);
479: sshbuf_free(state->incoming_packet);
480: for (mode = 0; mode < MODE_MAX; mode++)
481: kex_free_newkeys(state->newkeys[mode]);
482: if (state->compression_buffer) {
483: sshbuf_free(state->compression_buffer);
484: if (state->compression_out_started) {
485: z_streamp stream = &state->compression_out_stream;
486: debug("compress outgoing: "
487: "raw data %llu, compressed %llu, factor %.2f",
488: (unsigned long long)stream->total_in,
489: (unsigned long long)stream->total_out,
490: stream->total_in == 0 ? 0.0 :
491: (double) stream->total_out / stream->total_in);
492: if (state->compression_out_failures == 0)
493: deflateEnd(stream);
494: }
495: if (state->compression_in_started) {
496: z_streamp stream = &state->compression_out_stream;
497: debug("compress incoming: "
498: "raw data %llu, compressed %llu, factor %.2f",
499: (unsigned long long)stream->total_out,
500: (unsigned long long)stream->total_in,
501: stream->total_out == 0 ? 0.0 :
502: (double) stream->total_in / stream->total_out);
503: if (state->compression_in_failures == 0)
504: inflateEnd(stream);
505: }
1.14 markus 506: }
1.201 markus 507: if ((r = cipher_cleanup(&state->send_context)) != 0)
508: error("%s: cipher_cleanup failed: %s", __func__, ssh_err(r));
509: if ((r = cipher_cleanup(&state->receive_context)) != 0)
510: error("%s: cipher_cleanup failed: %s", __func__, ssh_err(r));
511: if (ssh->remote_ipaddr) {
512: free(ssh->remote_ipaddr);
513: ssh->remote_ipaddr = NULL;
514: }
515: free(ssh->state);
516: ssh->state = NULL;
1.1 deraadt 517: }
518:
519: /* Sets remote side protocol flags. */
520:
1.2 provos 521: void
1.201 markus 522: ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
1.1 deraadt 523: {
1.201 markus 524: ssh->state->remote_protocol_flags = protocol_flags;
1.1 deraadt 525: }
526:
527: /* Returns the remote protocol flags set earlier by the above function. */
528:
1.40 markus 529: u_int
1.201 markus 530: ssh_packet_get_protocol_flags(struct ssh *ssh)
1.1 deraadt 531: {
1.201 markus 532: return ssh->state->remote_protocol_flags;
1.1 deraadt 533: }
534:
1.16 markus 535: /*
536: * Starts packet compression from the next packet on in both directions.
537: * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
538: */
1.1 deraadt 539:
1.201 markus 540: static int
541: ssh_packet_init_compression(struct ssh *ssh)
1.60 markus 542: {
1.201 markus 543: if (!ssh->state->compression_buffer &&
544: ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
545: return SSH_ERR_ALLOC_FAIL;
546: return 0;
1.60 markus 547: }
548:
1.201 markus 549: static int
550: start_compression_out(struct ssh *ssh, int level)
1.1 deraadt 551: {
1.201 markus 552: if (level < 1 || level > 9)
553: return SSH_ERR_INVALID_ARGUMENT;
554: debug("Enabling compression at level %d.", level);
555: if (ssh->state->compression_out_started == 1)
556: deflateEnd(&ssh->state->compression_out_stream);
557: switch (deflateInit(&ssh->state->compression_out_stream, level)) {
558: case Z_OK:
559: ssh->state->compression_out_started = 1;
560: break;
561: case Z_MEM_ERROR:
562: return SSH_ERR_ALLOC_FAIL;
563: default:
564: return SSH_ERR_INTERNAL_ERROR;
565: }
566: return 0;
1.1 deraadt 567: }
568:
1.201 markus 569: static int
570: start_compression_in(struct ssh *ssh)
571: {
572: if (ssh->state->compression_in_started == 1)
573: inflateEnd(&ssh->state->compression_in_stream);
574: switch (inflateInit(&ssh->state->compression_in_stream)) {
575: case Z_OK:
576: ssh->state->compression_in_started = 1;
577: break;
578: case Z_MEM_ERROR:
579: return SSH_ERR_ALLOC_FAIL;
580: default:
581: return SSH_ERR_INTERNAL_ERROR;
582: }
583: return 0;
584: }
1.95 markus 585:
1.201 markus 586: int
587: ssh_packet_start_compression(struct ssh *ssh, int level)
1.1 deraadt 588: {
1.197 djm 589: int r;
1.97 deraadt 590:
1.201 markus 591: if (ssh->state->packet_compression && !compat20)
592: return SSH_ERR_INTERNAL_ERROR;
593: ssh->state->packet_compression = 1;
594: if ((r = ssh_packet_init_compression(ssh)) != 0 ||
595: (r = start_compression_in(ssh)) != 0 ||
596: (r = start_compression_out(ssh, level)) != 0)
597: return r;
598: return 0;
1.95 markus 599: }
600:
1.201 markus 601: /* XXX remove need for separate compression buffer */
602: static int
603: compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.95 markus 604: {
1.201 markus 605: u_char buf[4096];
606: int r, status;
607:
608: if (ssh->state->compression_out_started != 1)
609: return SSH_ERR_INTERNAL_ERROR;
610:
611: /* This case is not handled below. */
612: if (sshbuf_len(in) == 0)
613: return 0;
614:
615: /* Input is the contents of the input buffer. */
616: if ((ssh->state->compression_out_stream.next_in =
617: sshbuf_mutable_ptr(in)) == NULL)
618: return SSH_ERR_INTERNAL_ERROR;
619: ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
620:
621: /* Loop compressing until deflate() returns with avail_out != 0. */
622: do {
623: /* Set up fixed-size output buffer. */
624: ssh->state->compression_out_stream.next_out = buf;
625: ssh->state->compression_out_stream.avail_out = sizeof(buf);
626:
627: /* Compress as much data into the buffer as possible. */
628: status = deflate(&ssh->state->compression_out_stream,
629: Z_PARTIAL_FLUSH);
630: switch (status) {
631: case Z_MEM_ERROR:
632: return SSH_ERR_ALLOC_FAIL;
633: case Z_OK:
634: /* Append compressed data to output_buffer. */
635: if ((r = sshbuf_put(out, buf, sizeof(buf) -
636: ssh->state->compression_out_stream.avail_out)) != 0)
637: return r;
638: break;
639: case Z_STREAM_ERROR:
640: default:
641: ssh->state->compression_out_failures++;
642: return SSH_ERR_INVALID_FORMAT;
643: }
644: } while (ssh->state->compression_out_stream.avail_out == 0);
645: return 0;
1.1 deraadt 646: }
647:
1.201 markus 648: static int
649: uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.1 deraadt 650: {
1.201 markus 651: u_char buf[4096];
652: int r, status;
1.1 deraadt 653:
1.201 markus 654: if (ssh->state->compression_in_started != 1)
655: return SSH_ERR_INTERNAL_ERROR;
1.25 markus 656:
1.201 markus 657: if ((ssh->state->compression_in_stream.next_in =
658: sshbuf_mutable_ptr(in)) == NULL)
659: return SSH_ERR_INTERNAL_ERROR;
660: ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
1.97 deraadt 661:
1.201 markus 662: for (;;) {
663: /* Set up fixed-size output buffer. */
664: ssh->state->compression_in_stream.next_out = buf;
665: ssh->state->compression_in_stream.avail_out = sizeof(buf);
666:
667: status = inflate(&ssh->state->compression_in_stream,
668: Z_PARTIAL_FLUSH);
669: switch (status) {
670: case Z_OK:
671: if ((r = sshbuf_put(out, buf, sizeof(buf) -
672: ssh->state->compression_in_stream.avail_out)) != 0)
673: return r;
674: break;
675: case Z_BUF_ERROR:
676: /*
677: * Comments in zlib.h say that we should keep calling
678: * inflate() until we get an error. This appears to
679: * be the error that we get.
680: */
681: return 0;
682: case Z_DATA_ERROR:
683: return SSH_ERR_INVALID_FORMAT;
684: case Z_MEM_ERROR:
685: return SSH_ERR_ALLOC_FAIL;
686: case Z_STREAM_ERROR:
687: default:
688: ssh->state->compression_in_failures++;
689: return SSH_ERR_INTERNAL_ERROR;
690: }
691: }
692: /* NOTREACHED */
1.1 deraadt 693: }
1.125 deraadt 694:
1.201 markus 695: /* Serialise compression state into a blob for privsep */
696: static int
697: ssh_packet_get_compress_state(struct sshbuf *m, struct ssh *ssh)
1.1 deraadt 698: {
1.201 markus 699: struct session_state *state = ssh->state;
700: struct sshbuf *b;
701: int r;
702:
703: if ((b = sshbuf_new()) == NULL)
704: return SSH_ERR_ALLOC_FAIL;
705: if (state->compression_in_started) {
706: if ((r = sshbuf_put_string(b, &state->compression_in_stream,
707: sizeof(state->compression_in_stream))) != 0)
708: goto out;
709: } else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
710: goto out;
711: if (state->compression_out_started) {
712: if ((r = sshbuf_put_string(b, &state->compression_out_stream,
713: sizeof(state->compression_out_stream))) != 0)
714: goto out;
715: } else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
716: goto out;
717: r = sshbuf_put_stringb(m, b);
718: out:
719: sshbuf_free(b);
720: return r;
1.1 deraadt 721: }
1.125 deraadt 722:
1.201 markus 723: /* Deserialise compression state from a blob for privsep */
724: static int
725: ssh_packet_set_compress_state(struct ssh *ssh, struct sshbuf *m)
1.162 andreas 726: {
1.201 markus 727: struct session_state *state = ssh->state;
728: struct sshbuf *b = NULL;
729: int r;
730: const u_char *inblob, *outblob;
731: size_t inl, outl;
1.162 andreas 732:
1.201 markus 733: if ((r = sshbuf_froms(m, &b)) != 0)
734: goto out;
735: if ((r = sshbuf_get_string_direct(b, &inblob, &inl)) != 0 ||
736: (r = sshbuf_get_string_direct(b, &outblob, &outl)) != 0)
737: goto out;
738: if (inl == 0)
739: state->compression_in_started = 0;
740: else if (inl != sizeof(state->compression_in_stream)) {
741: r = SSH_ERR_INTERNAL_ERROR;
742: goto out;
743: } else {
744: state->compression_in_started = 1;
745: memcpy(&state->compression_in_stream, inblob, inl);
746: }
747: if (outl == 0)
748: state->compression_out_started = 0;
749: else if (outl != sizeof(state->compression_out_stream)) {
750: r = SSH_ERR_INTERNAL_ERROR;
751: goto out;
752: } else {
753: state->compression_out_started = 1;
754: memcpy(&state->compression_out_stream, outblob, outl);
755: }
756: r = 0;
757: out:
758: sshbuf_free(b);
759: return r;
1.1 deraadt 760: }
1.125 deraadt 761:
1.24 markus 762: void
1.201 markus 763: ssh_packet_set_compress_hooks(struct ssh *ssh, void *ctx,
764: void *(*allocfunc)(void *, u_int, u_int),
765: void (*freefunc)(void *, void *))
766: {
767: ssh->state->compression_out_stream.zalloc = (alloc_func)allocfunc;
768: ssh->state->compression_out_stream.zfree = (free_func)freefunc;
769: ssh->state->compression_out_stream.opaque = ctx;
770: ssh->state->compression_in_stream.zalloc = (alloc_func)allocfunc;
771: ssh->state->compression_in_stream.zfree = (free_func)freefunc;
772: ssh->state->compression_in_stream.opaque = ctx;
1.24 markus 773: }
1.125 deraadt 774:
1.201 markus 775: /*
776: * Causes any further packets to be encrypted using the given key. The same
777: * key is used for both sending and reception. However, both directions are
778: * encrypted independently of each other.
779: */
1.125 deraadt 780:
1.2 provos 781: void
1.201 markus 782: ssh_packet_set_encryption_key(struct ssh *ssh, const u_char *key, u_int keylen, int number)
1.1 deraadt 783: {
1.211 djm 784: #ifndef WITH_SSH1
785: fatal("no SSH protocol 1 support");
786: #else /* WITH_SSH1 */
1.201 markus 787: struct session_state *state = ssh->state;
788: const struct sshcipher *cipher = cipher_by_number(number);
789: int r;
790: const char *wmsg;
1.125 deraadt 791:
1.201 markus 792: if (cipher == NULL)
793: fatal("%s: unknown cipher number %d", __func__, number);
794: if (keylen < 20)
795: fatal("%s: keylen too small: %d", __func__, keylen);
796: if (keylen > SSH_SESSION_KEY_LENGTH)
797: fatal("%s: keylen too big: %d", __func__, keylen);
798: memcpy(state->ssh1_key, key, keylen);
799: state->ssh1_keylen = keylen;
800: if ((r = cipher_init(&state->send_context, cipher, key, keylen,
801: NULL, 0, CIPHER_ENCRYPT)) != 0 ||
802: (r = cipher_init(&state->receive_context, cipher, key, keylen,
803: NULL, 0, CIPHER_DECRYPT) != 0))
804: fatal("%s: cipher_init failed: %s", __func__, ssh_err(r));
805: if (!state->cipher_warning_done &&
806: ((wmsg = cipher_warning_message(&state->send_context)) != NULL ||
807: (wmsg = cipher_warning_message(&state->send_context)) != NULL)) {
808: error("Warning: %s", wmsg);
809: state->cipher_warning_done = 1;
810: }
1.211 djm 811: #endif /* WITH_SSH1 */
1.170 djm 812: }
813:
1.16 markus 814: /*
815: * Finalizes and sends the packet. If the encryption key has been set,
816: * encrypts the packet before sending.
817: */
1.14 markus 818:
1.201 markus 819: int
820: ssh_packet_send1(struct ssh *ssh)
1.1 deraadt 821: {
1.201 markus 822: struct session_state *state = ssh->state;
1.89 markus 823: u_char buf[8], *cp;
1.201 markus 824: int r, padding, len;
1.40 markus 825: u_int checksum;
1.14 markus 826:
1.16 markus 827: /*
828: * If using packet compression, compress the payload of the outgoing
829: * packet.
830: */
1.201 markus 831: if (state->packet_compression) {
832: sshbuf_reset(state->compression_buffer);
1.14 markus 833: /* Skip padding. */
1.201 markus 834: if ((r = sshbuf_consume(state->outgoing_packet, 8)) != 0)
835: goto out;
1.14 markus 836: /* padding */
1.201 markus 837: if ((r = sshbuf_put(state->compression_buffer,
838: "\0\0\0\0\0\0\0\0", 8)) != 0)
839: goto out;
840: if ((r = compress_buffer(ssh, state->outgoing_packet,
841: state->compression_buffer)) != 0)
842: goto out;
843: sshbuf_reset(state->outgoing_packet);
844: if ((r = sshbuf_putb(state->outgoing_packet,
845: state->compression_buffer)) != 0)
846: goto out;
1.14 markus 847: }
848: /* Compute packet length without padding (add checksum, remove padding). */
1.201 markus 849: len = sshbuf_len(state->outgoing_packet) + 4 - 8;
1.14 markus 850:
1.32 markus 851: /* Insert padding. Initialized to zero in packet_start1() */
1.14 markus 852: padding = 8 - len % 8;
1.201 markus 853: if (!state->send_context.plaintext) {
854: cp = sshbuf_mutable_ptr(state->outgoing_packet);
855: if (cp == NULL) {
856: r = SSH_ERR_INTERNAL_ERROR;
857: goto out;
1.14 markus 858: }
1.201 markus 859: arc4random_buf(cp + 8 - padding, padding);
1.14 markus 860: }
1.201 markus 861: if ((r = sshbuf_consume(state->outgoing_packet, 8 - padding)) != 0)
862: goto out;
1.14 markus 863:
864: /* Add check bytes. */
1.201 markus 865: checksum = ssh_crc32(sshbuf_ptr(state->outgoing_packet),
866: sshbuf_len(state->outgoing_packet));
867: POKE_U32(buf, checksum);
868: if ((r = sshbuf_put(state->outgoing_packet, buf, 4)) != 0)
869: goto out;
1.1 deraadt 870:
871: #ifdef PACKET_DEBUG
1.14 markus 872: fprintf(stderr, "packet_send plain: ");
1.201 markus 873: sshbuf_dump(state->outgoing_packet, stderr);
1.1 deraadt 874: #endif
875:
1.14 markus 876: /* Append to output. */
1.201 markus 877: POKE_U32(buf, len);
878: if ((r = sshbuf_put(state->output, buf, 4)) != 0)
879: goto out;
880: if ((r = sshbuf_reserve(state->output,
881: sshbuf_len(state->outgoing_packet), &cp)) != 0)
882: goto out;
883: if ((r = cipher_crypt(&state->send_context, 0, cp,
884: sshbuf_ptr(state->outgoing_packet),
885: sshbuf_len(state->outgoing_packet), 0, 0)) != 0)
886: goto out;
1.14 markus 887:
1.1 deraadt 888: #ifdef PACKET_DEBUG
1.14 markus 889: fprintf(stderr, "encrypted: ");
1.201 markus 890: sshbuf_dump(state->output, stderr);
1.1 deraadt 891: #endif
1.201 markus 892: state->p_send.packets++;
893: state->p_send.bytes += len +
894: sshbuf_len(state->outgoing_packet);
895: sshbuf_reset(state->outgoing_packet);
1.1 deraadt 896:
1.16 markus 897: /*
1.120 djm 898: * Note that the packet is now only buffered in output. It won't be
1.205 djm 899: * actually sent until ssh_packet_write_wait or ssh_packet_write_poll
900: * is called.
1.16 markus 901: */
1.201 markus 902: r = 0;
903: out:
904: return r;
1.1 deraadt 905: }
906:
1.201 markus 907: int
908: ssh_set_newkeys(struct ssh *ssh, int mode)
1.57 markus 909: {
1.201 markus 910: struct session_state *state = ssh->state;
911: struct sshenc *enc;
912: struct sshmac *mac;
913: struct sshcomp *comp;
914: struct sshcipher_ctx *cc;
1.105 markus 915: u_int64_t *max_blocks;
1.201 markus 916: const char *wmsg;
1.197 djm 917: int r, crypt_type;
1.57 markus 918:
1.100 markus 919: debug2("set_newkeys: mode %d", mode);
1.57 markus 920:
1.88 markus 921: if (mode == MODE_OUT) {
1.201 markus 922: cc = &state->send_context;
1.115 avsm 923: crypt_type = CIPHER_ENCRYPT;
1.201 markus 924: state->p_send.packets = state->p_send.blocks = 0;
925: max_blocks = &state->max_blocks_out;
1.88 markus 926: } else {
1.201 markus 927: cc = &state->receive_context;
1.115 avsm 928: crypt_type = CIPHER_DECRYPT;
1.201 markus 929: state->p_read.packets = state->p_read.blocks = 0;
930: max_blocks = &state->max_blocks_in;
1.88 markus 931: }
1.201 markus 932: if (state->newkeys[mode] != NULL) {
1.100 markus 933: debug("set_newkeys: rekeying");
1.201 markus 934: if ((r = cipher_cleanup(cc)) != 0)
935: return r;
936: enc = &state->newkeys[mode]->enc;
937: mac = &state->newkeys[mode]->mac;
938: comp = &state->newkeys[mode]->comp;
1.148 pvalchev 939: mac_clear(mac);
1.192 djm 940: explicit_bzero(enc->iv, enc->iv_len);
941: explicit_bzero(enc->key, enc->key_len);
942: explicit_bzero(mac->key, mac->key_len);
1.186 djm 943: free(enc->name);
944: free(enc->iv);
945: free(enc->key);
946: free(mac->name);
947: free(mac->key);
948: free(comp->name);
1.201 markus 949: free(state->newkeys[mode]);
1.57 markus 950: }
1.201 markus 951: /* move newkeys from kex to state */
952: if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
953: return SSH_ERR_INTERNAL_ERROR;
954: ssh->kex->newkeys[mode] = NULL;
955: enc = &state->newkeys[mode]->enc;
956: mac = &state->newkeys[mode]->mac;
957: comp = &state->newkeys[mode]->comp;
958: if (cipher_authlen(enc->cipher) == 0) {
959: if ((r = mac_init(mac)) != 0)
960: return r;
961: }
962: mac->enabled = 1;
1.57 markus 963: DBG(debug("cipher_init_context: %d", mode));
1.197 djm 964: if ((r = cipher_init(cc, enc->cipher, enc->key, enc->key_len,
965: enc->iv, enc->iv_len, crypt_type)) != 0)
1.201 markus 966: return r;
967: if (!state->cipher_warning_done &&
968: (wmsg = cipher_warning_message(cc)) != NULL) {
969: error("Warning: %s", wmsg);
970: state->cipher_warning_done = 1;
971: }
1.91 markus 972: /* Deleting the keys does not gain extra security */
1.192 djm 973: /* explicit_bzero(enc->iv, enc->block_size);
974: explicit_bzero(enc->key, enc->key_len);
975: explicit_bzero(mac->key, mac->key_len); */
1.118 markus 976: if ((comp->type == COMP_ZLIB ||
1.161 andreas 977: (comp->type == COMP_DELAYED &&
1.201 markus 978: state->after_authentication)) && comp->enabled == 0) {
979: if ((r = ssh_packet_init_compression(ssh)) < 0)
980: return r;
981: if (mode == MODE_OUT) {
982: if ((r = start_compression_out(ssh, 6)) != 0)
983: return r;
984: } else {
985: if ((r = start_compression_in(ssh)) != 0)
986: return r;
987: }
1.57 markus 988: comp->enabled = 1;
989: }
1.109 markus 990: /*
991: * The 2^(blocksize*2) limit is too expensive for 3DES,
992: * blowfish, etc, so enforce a 1GB limit for small blocksizes.
993: */
994: if (enc->block_size >= 16)
995: *max_blocks = (u_int64_t)1 << (enc->block_size*2);
996: else
997: *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1.201 markus 998: if (state->rekey_limit)
1.161 andreas 999: *max_blocks = MIN(*max_blocks,
1.201 markus 1000: state->rekey_limit / enc->block_size);
1001: return 0;
1.57 markus 1002: }
1003:
1.16 markus 1004: /*
1.118 markus 1005: * Delayed compression for SSH2 is enabled after authentication:
1.143 dtucker 1006: * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1.118 markus 1007: * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
1008: */
1.201 markus 1009: static int
1010: ssh_packet_enable_delayed_compress(struct ssh *ssh)
1.118 markus 1011: {
1.201 markus 1012: struct session_state *state = ssh->state;
1013: struct sshcomp *comp = NULL;
1014: int r, mode;
1.118 markus 1015:
1016: /*
1017: * Remember that we are past the authentication step, so rekeying
1018: * with COMP_DELAYED will turn on compression immediately.
1019: */
1.201 markus 1020: state->after_authentication = 1;
1.118 markus 1021: for (mode = 0; mode < MODE_MAX; mode++) {
1.145 markus 1022: /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1.201 markus 1023: if (state->newkeys[mode] == NULL)
1.145 markus 1024: continue;
1.201 markus 1025: comp = &state->newkeys[mode]->comp;
1.118 markus 1026: if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1.201 markus 1027: if ((r = ssh_packet_init_compression(ssh)) != 0)
1028: return r;
1029: if (mode == MODE_OUT) {
1030: if ((r = start_compression_out(ssh, 6)) != 0)
1031: return r;
1032: } else {
1033: if ((r = start_compression_in(ssh)) != 0)
1034: return r;
1035: }
1.118 markus 1036: comp->enabled = 1;
1037: }
1038: }
1.201 markus 1039: return 0;
1.118 markus 1040: }
1041:
1042: /*
1.25 markus 1043: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1044: */
1.201 markus 1045: int
1046: ssh_packet_send2_wrapped(struct ssh *ssh)
1.25 markus 1047: {
1.201 markus 1048: struct session_state *state = ssh->state;
1.200 markus 1049: u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1.178 markus 1050: u_char padlen, pad = 0;
1.201 markus 1051: u_int authlen = 0, aadlen = 0;
1052: u_int len;
1053: struct sshenc *enc = NULL;
1054: struct sshmac *mac = NULL;
1055: struct sshcomp *comp = NULL;
1056: int r, block_size;
1057:
1058: if (state->newkeys[MODE_OUT] != NULL) {
1059: enc = &state->newkeys[MODE_OUT]->enc;
1060: mac = &state->newkeys[MODE_OUT]->mac;
1061: comp = &state->newkeys[MODE_OUT]->comp;
1.180 markus 1062: /* disable mac for authenticated encryption */
1063: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1064: mac = NULL;
1.25 markus 1065: }
1.88 markus 1066: block_size = enc ? enc->block_size : 8;
1.180 markus 1067: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1068:
1.201 markus 1069: type = (sshbuf_ptr(state->outgoing_packet))[5];
1.25 markus 1070:
1071: #ifdef PACKET_DEBUG
1072: fprintf(stderr, "plain: ");
1.201 markus 1073: sshbuf_dump(state->outgoing_packet, stderr);
1.25 markus 1074: #endif
1075:
1076: if (comp && comp->enabled) {
1.201 markus 1077: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1078: /* skip header, compress only payload */
1.201 markus 1079: if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1080: goto out;
1081: sshbuf_reset(state->compression_buffer);
1082: if ((r = compress_buffer(ssh, state->outgoing_packet,
1083: state->compression_buffer)) != 0)
1084: goto out;
1085: sshbuf_reset(state->outgoing_packet);
1086: if ((r = sshbuf_put(state->outgoing_packet,
1087: "\0\0\0\0\0", 5)) != 0 ||
1088: (r = sshbuf_putb(state->outgoing_packet,
1089: state->compression_buffer)) != 0)
1090: goto out;
1091: DBG(debug("compression: raw %d compressed %zd", len,
1092: sshbuf_len(state->outgoing_packet)));
1.25 markus 1093: }
1094:
1095: /* sizeof (packet_len + pad_len + payload) */
1.201 markus 1096: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1097:
1098: /*
1099: * calc size of padding, alloc space, get random data,
1100: * minimum padding is 4 bytes
1101: */
1.178 markus 1102: len -= aadlen; /* packet length is not encrypted for EtM modes */
1.25 markus 1103: padlen = block_size - (len % block_size);
1104: if (padlen < 4)
1105: padlen += block_size;
1.201 markus 1106: if (state->extra_pad) {
1.71 markus 1107: /* will wrap if extra_pad+padlen > 255 */
1.201 markus 1108: state->extra_pad =
1109: roundup(state->extra_pad, block_size);
1110: pad = state->extra_pad -
1111: ((len + padlen) % state->extra_pad);
1.193 djm 1112: DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1.201 markus 1113: __func__, pad, len, padlen, state->extra_pad));
1.71 markus 1114: padlen += pad;
1.201 markus 1115: state->extra_pad = 0;
1.71 markus 1116: }
1.201 markus 1117: if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1118: goto out;
1119: if (enc && !state->send_context.plaintext) {
1.32 markus 1120: /* random padding */
1.201 markus 1121: arc4random_buf(cp, padlen);
1.32 markus 1122: } else {
1123: /* clear padding */
1.192 djm 1124: explicit_bzero(cp, padlen);
1.25 markus 1125: }
1.178 markus 1126: /* sizeof (packet_len + pad_len + payload + padding) */
1.201 markus 1127: len = sshbuf_len(state->outgoing_packet);
1128: cp = sshbuf_mutable_ptr(state->outgoing_packet);
1129: if (cp == NULL) {
1130: r = SSH_ERR_INTERNAL_ERROR;
1131: goto out;
1132: }
1.25 markus 1133: /* packet_length includes payload, padding and padding length field */
1.201 markus 1134: POKE_U32(cp, len - 4);
1.89 markus 1135: cp[4] = padlen;
1.178 markus 1136: DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1137: len, padlen, aadlen));
1.25 markus 1138:
1139: /* compute MAC over seqnr and packet(length fields, payload, padding) */
1.178 markus 1140: if (mac && mac->enabled && !mac->etm) {
1.201 markus 1141: if ((r = mac_compute(mac, state->p_send.seqnr,
1142: sshbuf_ptr(state->outgoing_packet), len,
1.200 markus 1143: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1144: goto out;
1145: DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1.25 markus 1146: }
1147: /* encrypt packet and append to output buffer. */
1.201 markus 1148: if ((r = sshbuf_reserve(state->output,
1149: sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1150: goto out;
1151: if ((r = cipher_crypt(&state->send_context, state->p_send.seqnr, cp,
1152: sshbuf_ptr(state->outgoing_packet),
1153: len - aadlen, aadlen, authlen)) != 0)
1154: goto out;
1.25 markus 1155: /* append unencrypted MAC */
1.178 markus 1156: if (mac && mac->enabled) {
1157: if (mac->etm) {
1158: /* EtM: compute mac over aadlen + cipher text */
1.201 markus 1159: if ((r = mac_compute(mac, state->p_send.seqnr,
1160: cp, len, macbuf, sizeof(macbuf))) != 0)
1161: goto out;
1.178 markus 1162: DBG(debug("done calc MAC(EtM) out #%d",
1.201 markus 1163: state->p_send.seqnr));
1.178 markus 1164: }
1.201 markus 1165: if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1166: goto out;
1.178 markus 1167: }
1.25 markus 1168: #ifdef PACKET_DEBUG
1169: fprintf(stderr, "encrypted: ");
1.201 markus 1170: sshbuf_dump(state->output, stderr);
1.25 markus 1171: #endif
1.29 markus 1172: /* increment sequence number for outgoing packets */
1.201 markus 1173: if (++state->p_send.seqnr == 0)
1.106 itojun 1174: logit("outgoing seqnr wraps around");
1.201 markus 1175: if (++state->p_send.packets == 0)
1176: if (!(ssh->compat & SSH_BUG_NOREKEY))
1177: return SSH_ERR_NEED_REKEY;
1178: state->p_send.blocks += len / block_size;
1179: state->p_send.bytes += len;
1180: sshbuf_reset(state->outgoing_packet);
1.25 markus 1181:
1.57 markus 1182: if (type == SSH2_MSG_NEWKEYS)
1.201 markus 1183: r = ssh_set_newkeys(ssh, MODE_OUT);
1184: else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1185: r = ssh_packet_enable_delayed_compress(ssh);
1186: else
1187: r = 0;
1188: out:
1189: return r;
1.25 markus 1190: }
1191:
1.201 markus 1192: int
1193: ssh_packet_send2(struct ssh *ssh)
1.105 markus 1194: {
1.201 markus 1195: struct session_state *state = ssh->state;
1.105 markus 1196: struct packet *p;
1.201 markus 1197: u_char type;
1198: int r;
1.105 markus 1199:
1.201 markus 1200: type = sshbuf_ptr(state->outgoing_packet)[5];
1.105 markus 1201:
1202: /* during rekeying we can only send key exchange messages */
1.201 markus 1203: if (state->rekeying) {
1.175 markus 1204: if ((type < SSH2_MSG_TRANSPORT_MIN) ||
1205: (type > SSH2_MSG_TRANSPORT_MAX) ||
1206: (type == SSH2_MSG_SERVICE_REQUEST) ||
1.218 ! markus 1207: (type == SSH2_MSG_SERVICE_ACCEPT) ||
! 1208: (type == SSH2_MSG_EXT_INFO)) {
1.105 markus 1209: debug("enqueue packet: %u", type);
1.201 markus 1210: p = calloc(1, sizeof(*p));
1211: if (p == NULL)
1212: return SSH_ERR_ALLOC_FAIL;
1.105 markus 1213: p->type = type;
1.201 markus 1214: p->payload = state->outgoing_packet;
1215: TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1216: state->outgoing_packet = sshbuf_new();
1217: if (state->outgoing_packet == NULL)
1218: return SSH_ERR_ALLOC_FAIL;
1219: return 0;
1.105 markus 1220: }
1221: }
1222:
1223: /* rekeying starts with sending KEXINIT */
1224: if (type == SSH2_MSG_KEXINIT)
1.201 markus 1225: state->rekeying = 1;
1.105 markus 1226:
1.201 markus 1227: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1228: return r;
1.105 markus 1229:
1230: /* after a NEWKEYS message we can send the complete queue */
1231: if (type == SSH2_MSG_NEWKEYS) {
1.201 markus 1232: state->rekeying = 0;
1233: state->rekey_time = monotime();
1234: while ((p = TAILQ_FIRST(&state->outgoing))) {
1.105 markus 1235: type = p->type;
1236: debug("dequeue packet: %u", type);
1.201 markus 1237: sshbuf_free(state->outgoing_packet);
1238: state->outgoing_packet = p->payload;
1239: TAILQ_REMOVE(&state->outgoing, p, next);
1.186 djm 1240: free(p);
1.201 markus 1241: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1242: return r;
1.105 markus 1243: }
1244: }
1.201 markus 1245: return 0;
1.25 markus 1246: }
1247:
1248: /*
1.16 markus 1249: * Waits until a packet has been received, and returns its type. Note that
1250: * no other data is processed until this returns, so this function should not
1251: * be used during the interactive session.
1252: */
1.1 deraadt 1253:
1.2 provos 1254: int
1.201 markus 1255: ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.1 deraadt 1256: {
1.201 markus 1257: struct session_state *state = ssh->state;
1258: int len, r, ms_remain, cont;
1.56 millert 1259: fd_set *setp;
1.14 markus 1260: char buf[8192];
1.155 deraadt 1261: struct timeval timeout, start, *timeoutp = NULL;
1262:
1.25 markus 1263: DBG(debug("packet_read()"));
1.14 markus 1264:
1.214 deraadt 1265: setp = calloc(howmany(state->connection_in + 1,
1.161 andreas 1266: NFDBITS), sizeof(fd_mask));
1.201 markus 1267: if (setp == NULL)
1268: return SSH_ERR_ALLOC_FAIL;
1.56 millert 1269:
1.205 djm 1270: /*
1271: * Since we are blocking, ensure that all written packets have
1272: * been sent.
1273: */
1.210 markus 1274: if ((r = ssh_packet_write_wait(ssh)) != 0)
1275: goto out;
1.14 markus 1276:
1277: /* Stay in the loop until we have received a complete packet. */
1278: for (;;) {
1279: /* Try to read a packet from the buffer. */
1.201 markus 1280: r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1281: if (r != 0)
1282: break;
1.62 markus 1283: if (!compat20 && (
1.201 markus 1284: *typep == SSH_SMSG_SUCCESS
1285: || *typep == SSH_SMSG_FAILURE
1286: || *typep == SSH_CMSG_EOF
1287: || *typep == SSH_CMSG_EXIT_CONFIRMATION))
1288: if ((r = sshpkt_get_end(ssh)) != 0)
1289: break;
1.14 markus 1290: /* If we got a packet, return it. */
1.201 markus 1291: if (*typep != SSH_MSG_NONE)
1292: break;
1.16 markus 1293: /*
1294: * Otherwise, wait for some data to arrive, add it to the
1295: * buffer, and try again.
1296: */
1.201 markus 1297: memset(setp, 0, howmany(state->connection_in + 1,
1.161 andreas 1298: NFDBITS) * sizeof(fd_mask));
1.201 markus 1299: FD_SET(state->connection_in, setp);
1.16 markus 1300:
1.201 markus 1301: if (state->packet_timeout_ms > 0) {
1302: ms_remain = state->packet_timeout_ms;
1.154 dtucker 1303: timeoutp = &timeout;
1304: }
1.14 markus 1305: /* Wait for some data to arrive. */
1.154 dtucker 1306: for (;;) {
1.201 markus 1307: if (state->packet_timeout_ms != -1) {
1.154 dtucker 1308: ms_to_timeval(&timeout, ms_remain);
1309: gettimeofday(&start, NULL);
1310: }
1.201 markus 1311: if ((r = select(state->connection_in + 1, setp,
1.161 andreas 1312: NULL, NULL, timeoutp)) >= 0)
1.154 dtucker 1313: break;
1.161 andreas 1314: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 1315: break;
1.201 markus 1316: if (state->packet_timeout_ms == -1)
1.154 dtucker 1317: continue;
1318: ms_subtract_diff(&start, &ms_remain);
1319: if (ms_remain <= 0) {
1.201 markus 1320: r = 0;
1.154 dtucker 1321: break;
1322: }
1323: }
1.204 djm 1324: if (r == 0)
1325: return SSH_ERR_CONN_TIMEOUT;
1.14 markus 1326: /* Read data from the socket. */
1.163 andreas 1327: do {
1328: cont = 0;
1.201 markus 1329: len = roaming_read(state->connection_in, buf,
1.163 andreas 1330: sizeof(buf), &cont);
1331: } while (len == 0 && cont);
1.210 markus 1332: if (len == 0) {
1333: r = SSH_ERR_CONN_CLOSED;
1334: goto out;
1335: }
1336: if (len < 0) {
1337: r = SSH_ERR_SYSTEM_ERROR;
1338: goto out;
1339: }
1.204 djm 1340:
1.14 markus 1341: /* Append it to the buffer. */
1.204 djm 1342: if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1.210 markus 1343: goto out;
1.14 markus 1344: }
1.210 markus 1345: out:
1.201 markus 1346: free(setp);
1347: return r;
1.1 deraadt 1348: }
1349:
1.77 djm 1350: int
1.201 markus 1351: ssh_packet_read(struct ssh *ssh)
1.77 djm 1352: {
1.201 markus 1353: u_char type;
1354: int r;
1355:
1356: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1357: fatal("%s: %s", __func__, ssh_err(r));
1358: return type;
1.77 djm 1359: }
1360:
1.16 markus 1361: /*
1362: * Waits until a packet has been received, verifies that its type matches
1363: * that given, and gives a fatal error and exits if there is a mismatch.
1364: */
1.1 deraadt 1365:
1.205 djm 1366: int
1367: ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1.1 deraadt 1368: {
1.205 djm 1369: int r;
1370: u_char type;
1.1 deraadt 1371:
1.205 djm 1372: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1373: return r;
1374: if (type != expected_type) {
1375: if ((r = sshpkt_disconnect(ssh,
1.201 markus 1376: "Protocol error: expected packet type %d, got %d",
1.205 djm 1377: expected_type, type)) != 0)
1378: return r;
1379: return SSH_ERR_PROTOCOL_ERROR;
1380: }
1381: return 0;
1.1 deraadt 1382: }
1383:
1384: /* Checks if a full packet is available in the data received so far via
1.14 markus 1385: * packet_process_incoming. If so, reads the packet; otherwise returns
1386: * SSH_MSG_NONE. This does not wait for data from the connection.
1387: *
1.150 dtucker 1388: * SSH_MSG_DISCONNECT is handled specially here. Also,
1389: * SSH_MSG_IGNORE messages are skipped by this function and are never returned
1390: * to higher levels.
1.14 markus 1391: */
1.1 deraadt 1392:
1.201 markus 1393: int
1394: ssh_packet_read_poll1(struct ssh *ssh, u_char *typep)
1.1 deraadt 1395: {
1.201 markus 1396: struct session_state *state = ssh->state;
1.40 markus 1397: u_int len, padded_len;
1.205 djm 1398: const char *emsg;
1.201 markus 1399: const u_char *cp;
1400: u_char *p;
1.40 markus 1401: u_int checksum, stored_checksum;
1.201 markus 1402: int r;
1403:
1404: *typep = SSH_MSG_NONE;
1.14 markus 1405:
1406: /* Check if input size is less than minimum packet size. */
1.201 markus 1407: if (sshbuf_len(state->input) < 4 + 8)
1408: return 0;
1.14 markus 1409: /* Get length of incoming packet. */
1.201 markus 1410: len = PEEK_U32(sshbuf_ptr(state->input));
1.205 djm 1411: if (len < 1 + 2 + 2 || len > 256 * 1024) {
1412: if ((r = sshpkt_disconnect(ssh, "Bad packet length %u",
1413: len)) != 0)
1414: return r;
1415: return SSH_ERR_CONN_CORRUPT;
1416: }
1.14 markus 1417: padded_len = (len + 8) & ~7;
1418:
1419: /* Check if the packet has been entirely received. */
1.201 markus 1420: if (sshbuf_len(state->input) < 4 + padded_len)
1421: return 0;
1.14 markus 1422:
1423: /* The entire packet is in buffer. */
1424:
1425: /* Consume packet length. */
1.201 markus 1426: if ((r = sshbuf_consume(state->input, 4)) != 0)
1427: goto out;
1.14 markus 1428:
1.62 markus 1429: /*
1430: * Cryptographic attack detector for ssh
1431: * (C)1998 CORE-SDI, Buenos Aires Argentina
1432: * Ariel Futoransky(futo@core-sdi.com)
1433: */
1.201 markus 1434: if (!state->receive_context.plaintext) {
1.205 djm 1435: emsg = NULL;
1.201 markus 1436: switch (detect_attack(&state->deattack,
1437: sshbuf_ptr(state->input), padded_len)) {
1438: case DEATTACK_OK:
1439: break;
1.144 djm 1440: case DEATTACK_DETECTED:
1.205 djm 1441: emsg = "crc32 compensation attack detected";
1442: break;
1.144 djm 1443: case DEATTACK_DOS_DETECTED:
1.205 djm 1444: emsg = "deattack denial of service detected";
1445: break;
1.201 markus 1446: default:
1.205 djm 1447: emsg = "deattack error";
1448: break;
1449: }
1450: if (emsg != NULL) {
1451: error("%s", emsg);
1452: if ((r = sshpkt_disconnect(ssh, "%s", emsg)) != 0 ||
1453: (r = ssh_packet_write_wait(ssh)) != 0)
1454: return r;
1455: return SSH_ERR_CONN_CORRUPT;
1.144 djm 1456: }
1457: }
1.62 markus 1458:
1459: /* Decrypt data to incoming_packet. */
1.201 markus 1460: sshbuf_reset(state->incoming_packet);
1461: if ((r = sshbuf_reserve(state->incoming_packet, padded_len, &p)) != 0)
1462: goto out;
1463: if ((r = cipher_crypt(&state->receive_context, 0, p,
1464: sshbuf_ptr(state->input), padded_len, 0, 0)) != 0)
1465: goto out;
1.62 markus 1466:
1.201 markus 1467: if ((r = sshbuf_consume(state->input, padded_len)) != 0)
1468: goto out;
1.1 deraadt 1469:
1470: #ifdef PACKET_DEBUG
1.14 markus 1471: fprintf(stderr, "read_poll plain: ");
1.201 markus 1472: sshbuf_dump(state->incoming_packet, stderr);
1.1 deraadt 1473: #endif
1474:
1.14 markus 1475: /* Compute packet checksum. */
1.201 markus 1476: checksum = ssh_crc32(sshbuf_ptr(state->incoming_packet),
1477: sshbuf_len(state->incoming_packet) - 4);
1.14 markus 1478:
1479: /* Skip padding. */
1.201 markus 1480: if ((r = sshbuf_consume(state->incoming_packet, 8 - len % 8)) != 0)
1481: goto out;
1.14 markus 1482:
1483: /* Test check bytes. */
1.205 djm 1484: if (len != sshbuf_len(state->incoming_packet)) {
1485: error("%s: len %d != sshbuf_len %zd", __func__,
1.201 markus 1486: len, sshbuf_len(state->incoming_packet));
1.205 djm 1487: if ((r = sshpkt_disconnect(ssh, "invalid packet length")) != 0 ||
1488: (r = ssh_packet_write_wait(ssh)) != 0)
1489: return r;
1490: return SSH_ERR_CONN_CORRUPT;
1491: }
1.14 markus 1492:
1.201 markus 1493: cp = sshbuf_ptr(state->incoming_packet) + len - 4;
1494: stored_checksum = PEEK_U32(cp);
1.205 djm 1495: if (checksum != stored_checksum) {
1496: error("Corrupted check bytes on input");
1497: if ((r = sshpkt_disconnect(ssh, "connection corrupted")) != 0 ||
1498: (r = ssh_packet_write_wait(ssh)) != 0)
1499: return r;
1500: return SSH_ERR_CONN_CORRUPT;
1501: }
1.201 markus 1502: if ((r = sshbuf_consume_end(state->incoming_packet, 4)) < 0)
1503: goto out;
1504:
1505: if (state->packet_compression) {
1506: sshbuf_reset(state->compression_buffer);
1507: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1508: state->compression_buffer)) != 0)
1509: goto out;
1510: sshbuf_reset(state->incoming_packet);
1511: if ((r = sshbuf_putb(state->incoming_packet,
1512: state->compression_buffer)) != 0)
1513: goto out;
1514: }
1515: state->p_read.packets++;
1516: state->p_read.bytes += padded_len + 4;
1517: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1518: goto out;
1.205 djm 1519: if (*typep < SSH_MSG_MIN || *typep > SSH_MSG_MAX) {
1520: error("Invalid ssh1 packet type: %d", *typep);
1521: if ((r = sshpkt_disconnect(ssh, "invalid packet type")) != 0 ||
1522: (r = ssh_packet_write_wait(ssh)) != 0)
1523: return r;
1524: return SSH_ERR_PROTOCOL_ERROR;
1525: }
1.201 markus 1526: r = 0;
1527: out:
1528: return r;
1.1 deraadt 1529: }
1.14 markus 1530:
1.201 markus 1531: int
1532: ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1533: {
1.201 markus 1534: struct session_state *state = ssh->state;
1.40 markus 1535: u_int padlen, need;
1.201 markus 1536: u_char *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1537: u_int maclen, aadlen = 0, authlen = 0, block_size;
1538: struct sshenc *enc = NULL;
1539: struct sshmac *mac = NULL;
1540: struct sshcomp *comp = NULL;
1.200 markus 1541: int r;
1.201 markus 1542:
1543: *typep = SSH_MSG_NONE;
1544:
1545: if (state->packet_discard)
1546: return 0;
1547:
1548: if (state->newkeys[MODE_IN] != NULL) {
1549: enc = &state->newkeys[MODE_IN]->enc;
1550: mac = &state->newkeys[MODE_IN]->mac;
1551: comp = &state->newkeys[MODE_IN]->comp;
1.180 markus 1552: /* disable mac for authenticated encryption */
1553: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1554: mac = NULL;
1.25 markus 1555: }
1556: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.88 markus 1557: block_size = enc ? enc->block_size : 8;
1.180 markus 1558: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1559:
1.201 markus 1560: if (aadlen && state->packlen == 0) {
1561: if (cipher_get_length(&state->receive_context,
1562: &state->packlen, state->p_read.seqnr,
1563: sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1564: return 0;
1565: if (state->packlen < 1 + 4 ||
1566: state->packlen > PACKET_MAX_SIZE) {
1.178 markus 1567: #ifdef PACKET_DEBUG
1.201 markus 1568: sshbuf_dump(state->input, stderr);
1.178 markus 1569: #endif
1.201 markus 1570: logit("Bad packet length %u.", state->packlen);
1571: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1572: return r;
1.217 djm 1573: return SSH_ERR_CONN_CORRUPT;
1.178 markus 1574: }
1.201 markus 1575: sshbuf_reset(state->incoming_packet);
1576: } else if (state->packlen == 0) {
1.25 markus 1577: /*
1578: * check if input size is less than the cipher block size,
1579: * decrypt first block and extract length of incoming packet
1580: */
1.201 markus 1581: if (sshbuf_len(state->input) < block_size)
1582: return 0;
1583: sshbuf_reset(state->incoming_packet);
1584: if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1585: &cp)) != 0)
1586: goto out;
1587: if ((r = cipher_crypt(&state->receive_context,
1588: state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1589: block_size, 0, 0)) != 0)
1590: goto out;
1591: state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1592: if (state->packlen < 1 + 4 ||
1593: state->packlen > PACKET_MAX_SIZE) {
1.110 markus 1594: #ifdef PACKET_DEBUG
1.201 markus 1595: fprintf(stderr, "input: \n");
1596: sshbuf_dump(state->input, stderr);
1597: fprintf(stderr, "incoming_packet: \n");
1598: sshbuf_dump(state->incoming_packet, stderr);
1.110 markus 1599: #endif
1.201 markus 1600: logit("Bad packet length %u.", state->packlen);
1601: return ssh_packet_start_discard(ssh, enc, mac,
1602: state->packlen, PACKET_MAX_SIZE);
1.25 markus 1603: }
1.201 markus 1604: if ((r = sshbuf_consume(state->input, block_size)) != 0)
1605: goto out;
1.25 markus 1606: }
1.201 markus 1607: DBG(debug("input: packet len %u", state->packlen+4));
1608:
1.178 markus 1609: if (aadlen) {
1610: /* only the payload is encrypted */
1.201 markus 1611: need = state->packlen;
1.178 markus 1612: } else {
1613: /*
1614: * the payload size and the payload are encrypted, but we
1615: * have a partial packet of block_size bytes
1616: */
1.201 markus 1617: need = 4 + state->packlen - block_size;
1.178 markus 1618: }
1.180 markus 1619: DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1620: " aadlen %d", block_size, need, maclen, authlen, aadlen));
1.158 markus 1621: if (need % block_size != 0) {
1622: logit("padding error: need %d block %d mod %d",
1.25 markus 1623: need, block_size, need % block_size);
1.201 markus 1624: return ssh_packet_start_discard(ssh, enc, mac,
1625: state->packlen, PACKET_MAX_SIZE - block_size);
1.158 markus 1626: }
1.25 markus 1627: /*
1628: * check if the entire packet has been received and
1.178 markus 1629: * decrypt into incoming_packet:
1630: * 'aadlen' bytes are unencrypted, but authenticated.
1.180 markus 1631: * 'need' bytes are encrypted, followed by either
1632: * 'authlen' bytes of authentication tag or
1.178 markus 1633: * 'maclen' bytes of message authentication code.
1.25 markus 1634: */
1.201 markus 1635: if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1636: return 0;
1.25 markus 1637: #ifdef PACKET_DEBUG
1638: fprintf(stderr, "read_poll enc/full: ");
1.201 markus 1639: sshbuf_dump(state->input, stderr);
1.25 markus 1640: #endif
1.178 markus 1641: /* EtM: compute mac over encrypted input */
1.201 markus 1642: if (mac && mac->enabled && mac->etm) {
1643: if ((r = mac_compute(mac, state->p_read.seqnr,
1644: sshbuf_ptr(state->input), aadlen + need,
1.200 markus 1645: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1646: goto out;
1647: }
1648: if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1649: &cp)) != 0)
1650: goto out;
1651: if ((r = cipher_crypt(&state->receive_context, state->p_read.seqnr, cp,
1652: sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1653: goto out;
1654: if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1655: goto out;
1.25 markus 1656: /*
1657: * compute MAC over seqnr and packet,
1658: * increment sequence number for incoming packet
1659: */
1.29 markus 1660: if (mac && mac->enabled) {
1.178 markus 1661: if (!mac->etm)
1.201 markus 1662: if ((r = mac_compute(mac, state->p_read.seqnr,
1663: sshbuf_ptr(state->incoming_packet),
1664: sshbuf_len(state->incoming_packet),
1.200 markus 1665: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1666: goto out;
1667: if (timingsafe_bcmp(macbuf, sshbuf_ptr(state->input),
1.161 andreas 1668: mac->mac_len) != 0) {
1.159 markus 1669: logit("Corrupted MAC on input.");
1670: if (need > PACKET_MAX_SIZE)
1.201 markus 1671: return SSH_ERR_INTERNAL_ERROR;
1672: return ssh_packet_start_discard(ssh, enc, mac,
1673: state->packlen, PACKET_MAX_SIZE - need);
1674: }
1675:
1676: DBG(debug("MAC #%d ok", state->p_read.seqnr));
1677: if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1678: goto out;
1.25 markus 1679: }
1.77 djm 1680: if (seqnr_p != NULL)
1.201 markus 1681: *seqnr_p = state->p_read.seqnr;
1682: if (++state->p_read.seqnr == 0)
1.106 itojun 1683: logit("incoming seqnr wraps around");
1.201 markus 1684: if (++state->p_read.packets == 0)
1685: if (!(ssh->compat & SSH_BUG_NOREKEY))
1686: return SSH_ERR_NEED_REKEY;
1687: state->p_read.blocks += (state->packlen + 4) / block_size;
1688: state->p_read.bytes += state->packlen + 4;
1.25 markus 1689:
1690: /* get padlen */
1.201 markus 1691: padlen = sshbuf_ptr(state->incoming_packet)[4];
1.25 markus 1692: DBG(debug("input: padlen %d", padlen));
1.205 djm 1693: if (padlen < 4) {
1694: if ((r = sshpkt_disconnect(ssh,
1695: "Corrupted padlen %d on input.", padlen)) != 0 ||
1696: (r = ssh_packet_write_wait(ssh)) != 0)
1697: return r;
1698: return SSH_ERR_CONN_CORRUPT;
1699: }
1.25 markus 1700:
1701: /* skip packet size + padlen, discard padding */
1.201 markus 1702: if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1703: ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1704: goto out;
1.25 markus 1705:
1.201 markus 1706: DBG(debug("input: len before de-compress %zd",
1707: sshbuf_len(state->incoming_packet)));
1.25 markus 1708: if (comp && comp->enabled) {
1.201 markus 1709: sshbuf_reset(state->compression_buffer);
1710: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1711: state->compression_buffer)) != 0)
1712: goto out;
1713: sshbuf_reset(state->incoming_packet);
1714: if ((r = sshbuf_putb(state->incoming_packet,
1715: state->compression_buffer)) != 0)
1716: goto out;
1717: DBG(debug("input: len after de-compress %zd",
1718: sshbuf_len(state->incoming_packet)));
1.25 markus 1719: }
1720: /*
1721: * get packet type, implies consume.
1722: * return length of payload (without type field)
1723: */
1.201 markus 1724: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1725: goto out;
1.205 djm 1726: if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1727: if ((r = sshpkt_disconnect(ssh,
1728: "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1729: (r = ssh_packet_write_wait(ssh)) != 0)
1730: return r;
1731: return SSH_ERR_PROTOCOL_ERROR;
1732: }
1.201 markus 1733: if (*typep == SSH2_MSG_NEWKEYS)
1734: r = ssh_set_newkeys(ssh, MODE_IN);
1735: else if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1736: r = ssh_packet_enable_delayed_compress(ssh);
1737: else
1738: r = 0;
1.25 markus 1739: #ifdef PACKET_DEBUG
1.201 markus 1740: fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1741: sshbuf_dump(state->incoming_packet, stderr);
1.25 markus 1742: #endif
1.62 markus 1743: /* reset for next packet */
1.201 markus 1744: state->packlen = 0;
1745: out:
1746: return r;
1.25 markus 1747: }
1748:
1749: int
1.201 markus 1750: ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1751: {
1.201 markus 1752: struct session_state *state = ssh->state;
1.96 deraadt 1753: u_int reason, seqnr;
1.201 markus 1754: int r;
1755: u_char *msg;
1.62 markus 1756:
1.25 markus 1757: for (;;) {
1.201 markus 1758: msg = NULL;
1.62 markus 1759: if (compat20) {
1.201 markus 1760: r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1761: if (r != 0)
1762: return r;
1763: if (*typep) {
1764: state->keep_alive_timeouts = 0;
1765: DBG(debug("received packet type %d", *typep));
1.153 djm 1766: }
1.201 markus 1767: switch (*typep) {
1.150 dtucker 1768: case SSH2_MSG_IGNORE:
1.151 dtucker 1769: debug3("Received SSH2_MSG_IGNORE");
1.150 dtucker 1770: break;
1.25 markus 1771: case SSH2_MSG_DEBUG:
1.201 markus 1772: if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1773: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1774: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1775: if (msg)
1776: free(msg);
1777: return r;
1778: }
1.25 markus 1779: debug("Remote: %.900s", msg);
1.186 djm 1780: free(msg);
1.25 markus 1781: break;
1782: case SSH2_MSG_DISCONNECT:
1.201 markus 1783: if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1784: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1785: return r;
1.182 djm 1786: /* Ignore normal client exit notifications */
1.201 markus 1787: do_log2(ssh->state->server_side &&
1.182 djm 1788: reason == SSH2_DISCONNECT_BY_APPLICATION ?
1789: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1790: "Received disconnect from %s: %u: %.400s",
1.201 markus 1791: ssh_remote_ipaddr(ssh), reason, msg);
1.186 djm 1792: free(msg);
1.201 markus 1793: return SSH_ERR_DISCONNECTED;
1.84 markus 1794: case SSH2_MSG_UNIMPLEMENTED:
1.201 markus 1795: if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1796: return r;
1.96 deraadt 1797: debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1798: seqnr);
1.150 dtucker 1799: break;
1.25 markus 1800: default:
1.201 markus 1801: return 0;
1.48 stevesk 1802: }
1.25 markus 1803: } else {
1.201 markus 1804: r = ssh_packet_read_poll1(ssh, typep);
1805: switch (*typep) {
1.188 djm 1806: case SSH_MSG_NONE:
1807: return SSH_MSG_NONE;
1.25 markus 1808: case SSH_MSG_IGNORE:
1809: break;
1810: case SSH_MSG_DEBUG:
1.201 markus 1811: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1812: return r;
1.25 markus 1813: debug("Remote: %.900s", msg);
1.186 djm 1814: free(msg);
1.25 markus 1815: break;
1816: case SSH_MSG_DISCONNECT:
1.201 markus 1817: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1818: return r;
1.181 djm 1819: error("Received disconnect from %s: %.400s",
1.201 markus 1820: ssh_remote_ipaddr(ssh), msg);
1821: free(msg);
1822: return SSH_ERR_DISCONNECTED;
1.25 markus 1823: default:
1.201 markus 1824: DBG(debug("received packet type %d", *typep));
1825: return 0;
1.48 stevesk 1826: }
1.25 markus 1827: }
1828: }
1829: }
1830:
1.16 markus 1831: /*
1832: * Buffers the given amount of input characters. This is intended to be used
1833: * together with packet_read_poll.
1834: */
1.1 deraadt 1835:
1.204 djm 1836: int
1.201 markus 1837: ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1.1 deraadt 1838: {
1.201 markus 1839: struct session_state *state = ssh->state;
1840: int r;
1841:
1842: if (state->packet_discard) {
1843: state->keep_alive_timeouts = 0; /* ?? */
1844: if (len >= state->packet_discard) {
1845: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1.204 djm 1846: return r;
1.201 markus 1847: }
1848: state->packet_discard -= len;
1.204 djm 1849: return 0;
1.159 markus 1850: }
1.201 markus 1851: if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1.204 djm 1852: return r;
1853:
1854: return 0;
1.28 markus 1855: }
1856:
1857: int
1.201 markus 1858: ssh_packet_remaining(struct ssh *ssh)
1.28 markus 1859: {
1.201 markus 1860: return sshbuf_len(ssh->state->incoming_packet);
1.1 deraadt 1861: }
1862:
1.16 markus 1863: /*
1864: * Sends a diagnostic message from the server to the client. This message
1865: * can be sent at any time (but not while constructing another message). The
1866: * message is printed immediately, but only if the client is being executed
1867: * in verbose mode. These messages are primarily intended to ease debugging
1868: * authentication problems. The length of the formatted message must not
1.205 djm 1869: * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1.16 markus 1870: */
1.2 provos 1871: void
1.201 markus 1872: ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1873: {
1.14 markus 1874: char buf[1024];
1875: va_list args;
1.201 markus 1876: int r;
1.39 markus 1877:
1.201 markus 1878: if (compat20 && (ssh->compat & SSH_BUG_DEBUG))
1.39 markus 1879: return;
1.14 markus 1880:
1881: va_start(args, fmt);
1882: vsnprintf(buf, sizeof(buf), fmt, args);
1883: va_end(args);
1884:
1.30 markus 1885: if (compat20) {
1.201 markus 1886: if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1887: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1888: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1889: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1890: (r = sshpkt_send(ssh)) != 0)
1891: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1892: } else {
1.201 markus 1893: if ((r = sshpkt_start(ssh, SSH_MSG_DEBUG)) != 0 ||
1894: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1895: (r = sshpkt_send(ssh)) != 0)
1896: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1897: }
1.205 djm 1898: if ((r = ssh_packet_write_wait(ssh)) != 0)
1899: fatal("%s: %s", __func__, ssh_err(r));
1900: }
1901:
1902: /*
1903: * Pretty-print connection-terminating errors and exit.
1904: */
1905: void
1906: sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1907: {
1908: switch (r) {
1909: case SSH_ERR_CONN_CLOSED:
1910: logit("Connection closed by %.200s", ssh_remote_ipaddr(ssh));
1911: cleanup_exit(255);
1912: case SSH_ERR_CONN_TIMEOUT:
1.212 djm 1913: logit("Connection to %.200s timed out", ssh_remote_ipaddr(ssh));
1.205 djm 1914: cleanup_exit(255);
1.212 djm 1915: case SSH_ERR_DISCONNECTED:
1916: logit("Disconnected from %.200s",
1917: ssh_remote_ipaddr(ssh));
1918: cleanup_exit(255);
1919: case SSH_ERR_SYSTEM_ERROR:
1920: if (errno == ECONNRESET) {
1921: logit("Connection reset by %.200s",
1922: ssh_remote_ipaddr(ssh));
1923: cleanup_exit(255);
1.213 djm 1924: }
1925: /* FALLTHROUGH */
1926: case SSH_ERR_NO_CIPHER_ALG_MATCH:
1927: case SSH_ERR_NO_MAC_ALG_MATCH:
1928: case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1929: case SSH_ERR_NO_KEX_ALG_MATCH:
1930: case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1931: if (ssh && ssh->kex && ssh->kex->failed_choice) {
1932: fatal("Unable to negotiate with %.200s: %s. "
1933: "Their offer: %s", ssh_remote_ipaddr(ssh),
1934: ssh_err(r), ssh->kex->failed_choice);
1.212 djm 1935: }
1936: /* FALLTHROUGH */
1.205 djm 1937: default:
1938: fatal("%s%sConnection to %.200s: %s",
1939: tag != NULL ? tag : "", tag != NULL ? ": " : "",
1940: ssh_remote_ipaddr(ssh), ssh_err(r));
1941: }
1.1 deraadt 1942: }
1943:
1.16 markus 1944: /*
1945: * Logs the error plus constructs and sends a disconnect packet, closes the
1946: * connection, and exits. This function never returns. The error message
1947: * should not contain a newline. The length of the formatted message must
1948: * not exceed 1024 bytes.
1949: */
1.2 provos 1950: void
1.201 markus 1951: ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1952: {
1.14 markus 1953: char buf[1024];
1954: va_list args;
1955: static int disconnecting = 0;
1.201 markus 1956: int r;
1.97 deraadt 1957:
1.14 markus 1958: if (disconnecting) /* Guard against recursive invocations. */
1959: fatal("packet_disconnect called recursively.");
1960: disconnecting = 1;
1961:
1.16 markus 1962: /*
1963: * Format the message. Note that the caller must make sure the
1964: * message is of limited size.
1965: */
1.14 markus 1966: va_start(args, fmt);
1967: vsnprintf(buf, sizeof(buf), fmt, args);
1968: va_end(args);
1969:
1.99 markus 1970: /* Display the error locally */
1.106 itojun 1971: logit("Disconnecting: %.100s", buf);
1.99 markus 1972:
1.205 djm 1973: /*
1974: * Send the disconnect message to the other side, and wait
1975: * for it to get sent.
1976: */
1977: if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1978: sshpkt_fatal(ssh, __func__, r);
1979:
1980: if ((r = ssh_packet_write_wait(ssh)) != 0)
1981: sshpkt_fatal(ssh, __func__, r);
1.14 markus 1982:
1983: /* Close the connection. */
1.201 markus 1984: ssh_packet_close(ssh);
1.112 markus 1985: cleanup_exit(255);
1.1 deraadt 1986: }
1987:
1.205 djm 1988: /*
1989: * Checks if there is any buffered output, and tries to write some of
1990: * the output.
1991: */
1992: int
1.201 markus 1993: ssh_packet_write_poll(struct ssh *ssh)
1.1 deraadt 1994: {
1.201 markus 1995: struct session_state *state = ssh->state;
1996: int len = sshbuf_len(state->output);
1997: int cont, r;
1.97 deraadt 1998:
1.14 markus 1999: if (len > 0) {
1.163 andreas 2000: cont = 0;
1.201 markus 2001: len = roaming_write(state->connection_out,
2002: sshbuf_ptr(state->output), len, &cont);
1.156 djm 2003: if (len == -1) {
2004: if (errno == EINTR || errno == EAGAIN)
1.205 djm 2005: return 0;
2006: return SSH_ERR_SYSTEM_ERROR;
1.14 markus 2007: }
1.163 andreas 2008: if (len == 0 && !cont)
1.205 djm 2009: return SSH_ERR_CONN_CLOSED;
1.201 markus 2010: if ((r = sshbuf_consume(state->output, len)) != 0)
1.205 djm 2011: return r;
1.14 markus 2012: }
1.205 djm 2013: return 0;
1.1 deraadt 2014: }
2015:
1.16 markus 2016: /*
2017: * Calls packet_write_poll repeatedly until all pending output data has been
2018: * written.
2019: */
1.205 djm 2020: int
1.201 markus 2021: ssh_packet_write_wait(struct ssh *ssh)
1.1 deraadt 2022: {
1.56 millert 2023: fd_set *setp;
1.205 djm 2024: int ret, r, ms_remain = 0;
1.154 dtucker 2025: struct timeval start, timeout, *timeoutp = NULL;
1.201 markus 2026: struct session_state *state = ssh->state;
1.56 millert 2027:
1.214 deraadt 2028: setp = calloc(howmany(state->connection_out + 1,
1.161 andreas 2029: NFDBITS), sizeof(fd_mask));
1.201 markus 2030: if (setp == NULL)
1.205 djm 2031: return SSH_ERR_ALLOC_FAIL;
1.216 gsoares 2032: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2033: free(setp);
1.215 djm 2034: return r;
1.216 gsoares 2035: }
1.201 markus 2036: while (ssh_packet_have_data_to_write(ssh)) {
2037: memset(setp, 0, howmany(state->connection_out + 1,
1.161 andreas 2038: NFDBITS) * sizeof(fd_mask));
1.201 markus 2039: FD_SET(state->connection_out, setp);
1.154 dtucker 2040:
1.201 markus 2041: if (state->packet_timeout_ms > 0) {
2042: ms_remain = state->packet_timeout_ms;
1.154 dtucker 2043: timeoutp = &timeout;
2044: }
2045: for (;;) {
1.201 markus 2046: if (state->packet_timeout_ms != -1) {
1.154 dtucker 2047: ms_to_timeval(&timeout, ms_remain);
2048: gettimeofday(&start, NULL);
2049: }
1.201 markus 2050: if ((ret = select(state->connection_out + 1,
1.161 andreas 2051: NULL, setp, NULL, timeoutp)) >= 0)
1.154 dtucker 2052: break;
1.161 andreas 2053: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 2054: break;
1.201 markus 2055: if (state->packet_timeout_ms == -1)
1.154 dtucker 2056: continue;
2057: ms_subtract_diff(&start, &ms_remain);
2058: if (ms_remain <= 0) {
2059: ret = 0;
2060: break;
2061: }
2062: }
2063: if (ret == 0) {
1.205 djm 2064: free(setp);
2065: return SSH_ERR_CONN_TIMEOUT;
2066: }
2067: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2068: free(setp);
2069: return r;
1.154 dtucker 2070: }
1.14 markus 2071: }
1.186 djm 2072: free(setp);
1.205 djm 2073: return 0;
1.1 deraadt 2074: }
2075:
2076: /* Returns true if there is buffered data to write to the connection. */
2077:
1.2 provos 2078: int
1.201 markus 2079: ssh_packet_have_data_to_write(struct ssh *ssh)
1.1 deraadt 2080: {
1.201 markus 2081: return sshbuf_len(ssh->state->output) != 0;
1.1 deraadt 2082: }
2083:
2084: /* Returns true if there is not too much data to write to the connection. */
2085:
1.2 provos 2086: int
1.201 markus 2087: ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1.1 deraadt 2088: {
1.201 markus 2089: if (ssh->state->interactive_mode)
2090: return sshbuf_len(ssh->state->output) < 16384;
1.14 markus 2091: else
1.201 markus 2092: return sshbuf_len(ssh->state->output) < 128 * 1024;
1.1 deraadt 2093: }
2094:
1.201 markus 2095: void
2096: ssh_packet_set_tos(struct ssh *ssh, int tos)
1.101 markus 2097: {
1.201 markus 2098: if (!ssh_packet_connection_is_on_socket(ssh))
1.101 markus 2099: return;
1.201 markus 2100: switch (ssh_packet_connection_af(ssh)) {
1.173 djm 2101: case AF_INET:
2102: debug3("%s: set IP_TOS 0x%02x", __func__, tos);
1.201 markus 2103: if (setsockopt(ssh->state->connection_in,
1.173 djm 2104: IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2105: error("setsockopt IP_TOS %d: %.100s:",
2106: tos, strerror(errno));
2107: break;
2108: case AF_INET6:
2109: debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
1.201 markus 2110: if (setsockopt(ssh->state->connection_in,
1.173 djm 2111: IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2112: error("setsockopt IPV6_TCLASS %d: %.100s:",
2113: tos, strerror(errno));
2114: break;
2115: }
1.101 markus 2116: }
2117:
1.1 deraadt 2118: /* Informs that the current session is interactive. Sets IP flags for that. */
2119:
1.2 provos 2120: void
1.201 markus 2121: ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
1.1 deraadt 2122: {
1.201 markus 2123: struct session_state *state = ssh->state;
2124:
2125: if (state->set_interactive_called)
1.43 markus 2126: return;
1.201 markus 2127: state->set_interactive_called = 1;
1.1 deraadt 2128:
1.14 markus 2129: /* Record that we are in interactive mode. */
1.201 markus 2130: state->interactive_mode = interactive;
1.1 deraadt 2131:
1.19 markus 2132: /* Only set socket options if using a socket. */
1.201 markus 2133: if (!ssh_packet_connection_is_on_socket(ssh))
1.14 markus 2134: return;
1.201 markus 2135: set_nodelay(state->connection_in);
2136: ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2137: qos_bulk);
1.1 deraadt 2138: }
2139:
2140: /* Returns true if the current connection is interactive. */
2141:
1.2 provos 2142: int
1.201 markus 2143: ssh_packet_is_interactive(struct ssh *ssh)
1.1 deraadt 2144: {
1.201 markus 2145: return ssh->state->interactive_mode;
1.12 markus 2146: }
2147:
1.113 deraadt 2148: int
1.201 markus 2149: ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
1.12 markus 2150: {
1.201 markus 2151: struct session_state *state = ssh->state;
2152:
2153: if (state->set_maxsize_called) {
1.106 itojun 2154: logit("packet_set_maxsize: called twice: old %d new %d",
1.201 markus 2155: state->max_packet_size, s);
1.14 markus 2156: return -1;
2157: }
2158: if (s < 4 * 1024 || s > 1024 * 1024) {
1.106 itojun 2159: logit("packet_set_maxsize: bad size %d", s);
1.14 markus 2160: return -1;
2161: }
1.201 markus 2162: state->set_maxsize_called = 1;
1.66 markus 2163: debug("packet_set_maxsize: setting to %d", s);
1.201 markus 2164: state->max_packet_size = s;
1.14 markus 2165: return s;
1.53 markus 2166: }
2167:
1.161 andreas 2168: int
1.201 markus 2169: ssh_packet_inc_alive_timeouts(struct ssh *ssh)
1.161 andreas 2170: {
1.201 markus 2171: return ++ssh->state->keep_alive_timeouts;
1.161 andreas 2172: }
2173:
2174: void
1.201 markus 2175: ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
1.161 andreas 2176: {
1.201 markus 2177: ssh->state->keep_alive_timeouts = ka;
1.161 andreas 2178: }
2179:
2180: u_int
1.201 markus 2181: ssh_packet_get_maxsize(struct ssh *ssh)
1.71 markus 2182: {
1.201 markus 2183: return ssh->state->max_packet_size;
1.71 markus 2184: }
2185:
1.53 markus 2186: /*
2187: * 9.2. Ignored Data Message
1.61 markus 2188: *
1.53 markus 2189: * byte SSH_MSG_IGNORE
2190: * string data
1.61 markus 2191: *
1.53 markus 2192: * All implementations MUST understand (and ignore) this message at any
2193: * time (after receiving the protocol version). No implementation is
2194: * required to send them. This message can be used as an additional
2195: * protection measure against advanced traffic analysis techniques.
2196: */
1.54 markus 2197: void
1.201 markus 2198: ssh_packet_send_ignore(struct ssh *ssh, int nbytes)
1.54 markus 2199: {
1.115 avsm 2200: u_int32_t rnd = 0;
1.201 markus 2201: int r, i;
1.54 markus 2202:
1.201 markus 2203: if ((r = sshpkt_start(ssh, compat20 ?
2204: SSH2_MSG_IGNORE : SSH_MSG_IGNORE)) != 0 ||
2205: (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2206: fatal("%s: %s", __func__, ssh_err(r));
1.75 deraadt 2207: for (i = 0; i < nbytes; i++) {
1.53 markus 2208: if (i % 4 == 0)
1.115 avsm 2209: rnd = arc4random();
1.201 markus 2210: if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2211: fatal("%s: %s", __func__, ssh_err(r));
1.115 avsm 2212: rnd >>= 8;
1.53 markus 2213: }
1.105 markus 2214: }
2215:
1.113 deraadt 2216: #define MAX_PACKETS (1U<<31)
1.105 markus 2217: int
1.201 markus 2218: ssh_packet_need_rekeying(struct ssh *ssh)
1.105 markus 2219: {
1.201 markus 2220: struct session_state *state = ssh->state;
2221:
2222: if (ssh->compat & SSH_BUG_NOREKEY)
1.105 markus 2223: return 0;
2224: return
1.201 markus 2225: (state->p_send.packets > MAX_PACKETS) ||
2226: (state->p_read.packets > MAX_PACKETS) ||
2227: (state->max_blocks_out &&
2228: (state->p_send.blocks > state->max_blocks_out)) ||
2229: (state->max_blocks_in &&
2230: (state->p_read.blocks > state->max_blocks_in)) ||
2231: (state->rekey_interval != 0 && state->rekey_time +
2232: state->rekey_interval <= monotime());
1.105 markus 2233: }
2234:
2235: void
1.201 markus 2236: ssh_packet_set_rekey_limits(struct ssh *ssh, u_int32_t bytes, time_t seconds)
1.105 markus 2237: {
1.184 dtucker 2238: debug3("rekey after %lld bytes, %d seconds", (long long)bytes,
2239: (int)seconds);
1.201 markus 2240: ssh->state->rekey_limit = bytes;
2241: ssh->state->rekey_interval = seconds;
1.184 dtucker 2242: }
2243:
2244: time_t
1.201 markus 2245: ssh_packet_get_rekey_timeout(struct ssh *ssh)
1.184 dtucker 2246: {
2247: time_t seconds;
2248:
1.201 markus 2249: seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
1.187 dtucker 2250: monotime();
1.185 dtucker 2251: return (seconds <= 0 ? 1 : seconds);
1.118 markus 2252: }
2253:
2254: void
1.201 markus 2255: ssh_packet_set_server(struct ssh *ssh)
1.118 markus 2256: {
1.201 markus 2257: ssh->state->server_side = 1;
1.118 markus 2258: }
2259:
2260: void
1.201 markus 2261: ssh_packet_set_authenticated(struct ssh *ssh)
1.118 markus 2262: {
1.201 markus 2263: ssh->state->after_authentication = 1;
1.161 andreas 2264: }
2265:
2266: void *
1.201 markus 2267: ssh_packet_get_input(struct ssh *ssh)
1.161 andreas 2268: {
1.201 markus 2269: return (void *)ssh->state->input;
1.161 andreas 2270: }
2271:
2272: void *
1.201 markus 2273: ssh_packet_get_output(struct ssh *ssh)
1.161 andreas 2274: {
1.201 markus 2275: return (void *)ssh->state->output;
1.166 andreas 2276: }
2277:
1.201 markus 2278: /* XXX TODO update roaming to new API (does not work anyway) */
1.166 andreas 2279: /*
2280: * Save the state for the real connection, and use a separate state when
2281: * resuming a suspended connection.
2282: */
2283: void
1.201 markus 2284: ssh_packet_backup_state(struct ssh *ssh,
2285: struct ssh *backup_state)
1.166 andreas 2286: {
1.201 markus 2287: struct ssh *tmp;
1.166 andreas 2288:
1.201 markus 2289: close(ssh->state->connection_in);
2290: ssh->state->connection_in = -1;
2291: close(ssh->state->connection_out);
2292: ssh->state->connection_out = -1;
1.166 andreas 2293: if (backup_state)
2294: tmp = backup_state;
2295: else
1.201 markus 2296: tmp = ssh_alloc_session_state();
2297: backup_state = ssh;
2298: ssh = tmp;
1.166 andreas 2299: }
2300:
1.201 markus 2301: /* XXX FIXME FIXME FIXME */
1.166 andreas 2302: /*
2303: * Swap in the old state when resuming a connecion.
2304: */
2305: void
1.201 markus 2306: ssh_packet_restore_state(struct ssh *ssh,
2307: struct ssh *backup_state)
1.166 andreas 2308: {
1.201 markus 2309: struct ssh *tmp;
1.166 andreas 2310: u_int len;
1.201 markus 2311: int r;
1.166 andreas 2312:
2313: tmp = backup_state;
1.201 markus 2314: backup_state = ssh;
2315: ssh = tmp;
2316: ssh->state->connection_in = backup_state->state->connection_in;
2317: backup_state->state->connection_in = -1;
2318: ssh->state->connection_out = backup_state->state->connection_out;
2319: backup_state->state->connection_out = -1;
2320: len = sshbuf_len(backup_state->state->input);
1.166 andreas 2321: if (len > 0) {
1.201 markus 2322: if ((r = sshbuf_putb(ssh->state->input,
2323: backup_state->state->input)) != 0)
2324: fatal("%s: %s", __func__, ssh_err(r));
2325: sshbuf_reset(backup_state->state->input);
1.166 andreas 2326: add_recv_bytes(len);
1.196 markus 2327: }
2328: }
2329:
2330: /* Reset after_authentication and reset compression in post-auth privsep */
1.201 markus 2331: static int
2332: ssh_packet_set_postauth(struct ssh *ssh)
1.196 markus 2333: {
1.201 markus 2334: struct sshcomp *comp;
2335: int r, mode;
1.196 markus 2336:
2337: debug("%s: called", __func__);
2338: /* This was set in net child, but is not visible in user child */
1.201 markus 2339: ssh->state->after_authentication = 1;
2340: ssh->state->rekeying = 0;
1.196 markus 2341: for (mode = 0; mode < MODE_MAX; mode++) {
1.201 markus 2342: if (ssh->state->newkeys[mode] == NULL)
1.196 markus 2343: continue;
1.201 markus 2344: comp = &ssh->state->newkeys[mode]->comp;
2345: if (comp && comp->enabled &&
2346: (r = ssh_packet_init_compression(ssh)) != 0)
2347: return r;
2348: }
2349: return 0;
2350: }
2351:
2352: /* Packet state (de-)serialization for privsep */
2353:
2354: /* turn kex into a blob for packet state serialization */
2355: static int
2356: kex_to_blob(struct sshbuf *m, struct kex *kex)
2357: {
2358: int r;
2359:
2360: if ((r = sshbuf_put_string(m, kex->session_id,
2361: kex->session_id_len)) != 0 ||
2362: (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2363: (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2364: (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2365: (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2366: (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2367: (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2368: (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2369: (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2370: return r;
2371: return 0;
2372: }
2373:
2374: /* turn key exchange results into a blob for packet state serialization */
2375: static int
2376: newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2377: {
2378: struct sshbuf *b;
2379: struct sshcipher_ctx *cc;
2380: struct sshcomp *comp;
2381: struct sshenc *enc;
2382: struct sshmac *mac;
2383: struct newkeys *newkey;
2384: int r;
2385:
2386: if ((newkey = ssh->state->newkeys[mode]) == NULL)
2387: return SSH_ERR_INTERNAL_ERROR;
2388: enc = &newkey->enc;
2389: mac = &newkey->mac;
2390: comp = &newkey->comp;
2391: cc = (mode == MODE_OUT) ? &ssh->state->send_context :
2392: &ssh->state->receive_context;
2393: if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2394: return r;
2395: if ((b = sshbuf_new()) == NULL)
2396: return SSH_ERR_ALLOC_FAIL;
2397: /* The cipher struct is constant and shared, you export pointer */
2398: if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2399: (r = sshbuf_put(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2400: (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2401: (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2402: (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2403: (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2404: goto out;
2405: if (cipher_authlen(enc->cipher) == 0) {
2406: if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2407: (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2408: (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2409: goto out;
2410: }
2411: if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2412: (r = sshbuf_put_u32(b, comp->enabled)) != 0 ||
2413: (r = sshbuf_put_cstring(b, comp->name)) != 0)
2414: goto out;
2415: r = sshbuf_put_stringb(m, b);
2416: out:
2417: if (b != NULL)
2418: sshbuf_free(b);
2419: return r;
2420: }
2421:
2422: /* serialize packet state into a blob */
2423: int
2424: ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2425: {
2426: struct session_state *state = ssh->state;
2427: u_char *p;
2428: size_t slen, rlen;
2429: int r, ssh1cipher;
2430:
2431: if (!compat20) {
2432: ssh1cipher = cipher_get_number(state->receive_context.cipher);
2433: slen = cipher_get_keyiv_len(&state->send_context);
2434: rlen = cipher_get_keyiv_len(&state->receive_context);
2435: if ((r = sshbuf_put_u32(m, state->remote_protocol_flags)) != 0 ||
2436: (r = sshbuf_put_u32(m, ssh1cipher)) != 0 ||
2437: (r = sshbuf_put_string(m, state->ssh1_key, state->ssh1_keylen)) != 0 ||
2438: (r = sshbuf_put_u32(m, slen)) != 0 ||
2439: (r = sshbuf_reserve(m, slen, &p)) != 0 ||
2440: (r = cipher_get_keyiv(&state->send_context, p, slen)) != 0 ||
2441: (r = sshbuf_put_u32(m, rlen)) != 0 ||
2442: (r = sshbuf_reserve(m, rlen, &p)) != 0 ||
2443: (r = cipher_get_keyiv(&state->receive_context, p, rlen)) != 0)
2444: return r;
2445: } else {
2446: if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2447: (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2448: (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
1.208 markus 2449: (r = sshbuf_put_u32(m, state->rekey_limit)) != 0 ||
2450: (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
1.201 markus 2451: (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2452: (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2453: (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2454: (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2455: (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2456: (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2457: (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2458: (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0)
2459: return r;
2460: }
2461:
2462: slen = cipher_get_keycontext(&state->send_context, NULL);
2463: rlen = cipher_get_keycontext(&state->receive_context, NULL);
2464: if ((r = sshbuf_put_u32(m, slen)) != 0 ||
2465: (r = sshbuf_reserve(m, slen, &p)) != 0)
2466: return r;
2467: if (cipher_get_keycontext(&state->send_context, p) != (int)slen)
2468: return SSH_ERR_INTERNAL_ERROR;
2469: if ((r = sshbuf_put_u32(m, rlen)) != 0 ||
2470: (r = sshbuf_reserve(m, rlen, &p)) != 0)
2471: return r;
2472: if (cipher_get_keycontext(&state->receive_context, p) != (int)rlen)
2473: return SSH_ERR_INTERNAL_ERROR;
2474:
2475: if ((r = ssh_packet_get_compress_state(m, ssh)) != 0 ||
2476: (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2477: (r = sshbuf_put_stringb(m, state->output)) != 0)
2478: return r;
2479:
2480: if (compat20) {
2481: if ((r = sshbuf_put_u64(m, get_sent_bytes())) != 0 ||
2482: (r = sshbuf_put_u64(m, get_recv_bytes())) != 0)
2483: return r;
2484: }
2485: return 0;
2486: }
2487:
2488: /* restore key exchange results from blob for packet state de-serialization */
2489: static int
2490: newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2491: {
2492: struct sshbuf *b = NULL;
2493: struct sshcomp *comp;
2494: struct sshenc *enc;
2495: struct sshmac *mac;
2496: struct newkeys *newkey = NULL;
2497: size_t keylen, ivlen, maclen;
2498: int r;
2499:
2500: if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2501: r = SSH_ERR_ALLOC_FAIL;
2502: goto out;
2503: }
2504: if ((r = sshbuf_froms(m, &b)) != 0)
2505: goto out;
2506: #ifdef DEBUG_PK
2507: sshbuf_dump(b, stderr);
2508: #endif
2509: enc = &newkey->enc;
2510: mac = &newkey->mac;
2511: comp = &newkey->comp;
2512:
2513: if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2514: (r = sshbuf_get(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2515: (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2516: (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2517: (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2518: (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2519: goto out;
2520: if (cipher_authlen(enc->cipher) == 0) {
2521: if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2522: goto out;
2523: if ((r = mac_setup(mac, mac->name)) != 0)
2524: goto out;
2525: if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2526: (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2527: goto out;
2528: if (maclen > mac->key_len) {
2529: r = SSH_ERR_INVALID_FORMAT;
2530: goto out;
2531: }
2532: mac->key_len = maclen;
2533: }
2534: if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2535: (r = sshbuf_get_u32(b, (u_int *)&comp->enabled)) != 0 ||
2536: (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2537: goto out;
2538: if (enc->name == NULL ||
2539: cipher_by_name(enc->name) != enc->cipher) {
2540: r = SSH_ERR_INVALID_FORMAT;
2541: goto out;
2542: }
2543: if (sshbuf_len(b) != 0) {
2544: r = SSH_ERR_INVALID_FORMAT;
2545: goto out;
2546: }
2547: enc->key_len = keylen;
2548: enc->iv_len = ivlen;
2549: ssh->kex->newkeys[mode] = newkey;
2550: newkey = NULL;
2551: r = 0;
2552: out:
2553: if (newkey != NULL)
2554: free(newkey);
2555: if (b != NULL)
2556: sshbuf_free(b);
2557: return r;
2558: }
2559:
2560: /* restore kex from blob for packet state de-serialization */
2561: static int
2562: kex_from_blob(struct sshbuf *m, struct kex **kexp)
2563: {
2564: struct kex *kex;
2565: int r;
2566:
2567: if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2568: (kex->my = sshbuf_new()) == NULL ||
2569: (kex->peer = sshbuf_new()) == NULL) {
2570: r = SSH_ERR_ALLOC_FAIL;
2571: goto out;
2572: }
2573: if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2574: (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2575: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2576: (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2577: (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2578: (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2579: (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2580: (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2581: (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2582: goto out;
2583: kex->server = 1;
2584: kex->done = 1;
2585: r = 0;
2586: out:
2587: if (r != 0 || kexp == NULL) {
2588: if (kex != NULL) {
2589: if (kex->my != NULL)
2590: sshbuf_free(kex->my);
2591: if (kex->peer != NULL)
2592: sshbuf_free(kex->peer);
2593: free(kex);
2594: }
2595: if (kexp != NULL)
2596: *kexp = NULL;
2597: } else {
2598: *kexp = kex;
2599: }
2600: return r;
2601: }
2602:
2603: /*
2604: * Restore packet state from content of blob 'm' (de-serialization).
2605: * Note that 'm' will be partially consumed on parsing or any other errors.
2606: */
2607: int
2608: ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2609: {
2610: struct session_state *state = ssh->state;
2611: const u_char *ssh1key, *ivin, *ivout, *keyin, *keyout, *input, *output;
2612: size_t ssh1keylen, rlen, slen, ilen, olen;
2613: int r;
2614: u_int ssh1cipher = 0;
2615: u_int64_t sent_bytes = 0, recv_bytes = 0;
2616:
2617: if (!compat20) {
2618: if ((r = sshbuf_get_u32(m, &state->remote_protocol_flags)) != 0 ||
2619: (r = sshbuf_get_u32(m, &ssh1cipher)) != 0 ||
2620: (r = sshbuf_get_string_direct(m, &ssh1key, &ssh1keylen)) != 0 ||
2621: (r = sshbuf_get_string_direct(m, &ivout, &slen)) != 0 ||
2622: (r = sshbuf_get_string_direct(m, &ivin, &rlen)) != 0)
2623: return r;
2624: if (ssh1cipher > INT_MAX)
2625: return SSH_ERR_KEY_UNKNOWN_CIPHER;
2626: ssh_packet_set_encryption_key(ssh, ssh1key, ssh1keylen,
2627: (int)ssh1cipher);
2628: if (cipher_get_keyiv_len(&state->send_context) != (int)slen ||
2629: cipher_get_keyiv_len(&state->receive_context) != (int)rlen)
2630: return SSH_ERR_INVALID_FORMAT;
2631: if ((r = cipher_set_keyiv(&state->send_context, ivout)) != 0 ||
2632: (r = cipher_set_keyiv(&state->receive_context, ivin)) != 0)
2633: return r;
2634: } else {
2635: if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2636: (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2637: (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
1.208 markus 2638: (r = sshbuf_get_u32(m, &state->rekey_limit)) != 0 ||
2639: (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
1.201 markus 2640: (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2641: (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2642: (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2643: (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2644: (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2645: (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2646: (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2647: (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2648: return r;
1.208 markus 2649: /*
2650: * We set the time here so that in post-auth privsep slave we
2651: * count from the completion of the authentication.
2652: */
2653: state->rekey_time = monotime();
1.201 markus 2654: /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2655: if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2656: (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2657: return r;
2658: }
2659: if ((r = sshbuf_get_string_direct(m, &keyout, &slen)) != 0 ||
2660: (r = sshbuf_get_string_direct(m, &keyin, &rlen)) != 0)
2661: return r;
2662: if (cipher_get_keycontext(&state->send_context, NULL) != (int)slen ||
2663: cipher_get_keycontext(&state->receive_context, NULL) != (int)rlen)
2664: return SSH_ERR_INVALID_FORMAT;
2665: cipher_set_keycontext(&state->send_context, keyout);
2666: cipher_set_keycontext(&state->receive_context, keyin);
2667:
2668: if ((r = ssh_packet_set_compress_state(ssh, m)) != 0 ||
2669: (r = ssh_packet_set_postauth(ssh)) != 0)
2670: return r;
2671:
2672: sshbuf_reset(state->input);
2673: sshbuf_reset(state->output);
2674: if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2675: (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2676: (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2677: (r = sshbuf_put(state->output, output, olen)) != 0)
2678: return r;
2679:
2680: if (compat20) {
2681: if ((r = sshbuf_get_u64(m, &sent_bytes)) != 0 ||
2682: (r = sshbuf_get_u64(m, &recv_bytes)) != 0)
2683: return r;
2684: roam_set_bytes(sent_bytes, recv_bytes);
2685: }
2686: if (sshbuf_len(m))
2687: return SSH_ERR_INVALID_FORMAT;
2688: debug3("%s: done", __func__);
2689: return 0;
2690: }
2691:
2692: /* NEW API */
2693:
2694: /* put data to the outgoing packet */
2695:
2696: int
2697: sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2698: {
2699: return sshbuf_put(ssh->state->outgoing_packet, v, len);
2700: }
2701:
2702: int
2703: sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2704: {
2705: return sshbuf_putb(ssh->state->outgoing_packet, b);
2706: }
2707:
2708: int
2709: sshpkt_put_u8(struct ssh *ssh, u_char val)
2710: {
2711: return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2712: }
2713:
2714: int
2715: sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2716: {
2717: return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2718: }
2719:
2720: int
2721: sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2722: {
2723: return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2724: }
2725:
2726: int
2727: sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2728: {
2729: return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2730: }
2731:
2732: int
2733: sshpkt_put_cstring(struct ssh *ssh, const void *v)
2734: {
2735: return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2736: }
2737:
2738: int
2739: sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2740: {
2741: return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2742: }
2743:
1.211 djm 2744: #ifdef WITH_OPENSSL
1.201 markus 2745: int
2746: sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2747: {
2748: return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2749: }
2750:
1.211 djm 2751: #ifdef WITH_SSH1
1.201 markus 2752: int
2753: sshpkt_put_bignum1(struct ssh *ssh, const BIGNUM *v)
2754: {
2755: return sshbuf_put_bignum1(ssh->state->outgoing_packet, v);
2756: }
1.211 djm 2757: #endif /* WITH_SSH1 */
1.201 markus 2758:
2759: int
2760: sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2761: {
2762: return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2763: }
1.211 djm 2764: #endif /* WITH_OPENSSL */
1.201 markus 2765:
2766: /* fetch data from the incoming packet */
2767:
2768: int
2769: sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2770: {
2771: return sshbuf_get(ssh->state->incoming_packet, valp, len);
2772: }
2773:
2774: int
2775: sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2776: {
2777: return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2778: }
2779:
2780: int
2781: sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2782: {
2783: return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2784: }
2785:
2786: int
2787: sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2788: {
2789: return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2790: }
2791:
2792: int
2793: sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2794: {
2795: return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2796: }
2797:
2798: int
2799: sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2800: {
2801: return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2802: }
2803:
2804: int
2805: sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2806: {
2807: return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2808: }
2809:
1.211 djm 2810: #ifdef WITH_OPENSSL
1.201 markus 2811: int
2812: sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2813: {
2814: return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2815: }
2816:
1.211 djm 2817: #ifdef WITH_SSH1
1.201 markus 2818: int
2819: sshpkt_get_bignum1(struct ssh *ssh, BIGNUM *v)
2820: {
2821: return sshbuf_get_bignum1(ssh->state->incoming_packet, v);
2822: }
1.211 djm 2823: #endif /* WITH_SSH1 */
1.201 markus 2824:
2825: int
2826: sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2827: {
2828: return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2829: }
1.211 djm 2830: #endif /* WITH_OPENSSL */
1.201 markus 2831:
2832: int
2833: sshpkt_get_end(struct ssh *ssh)
2834: {
2835: if (sshbuf_len(ssh->state->incoming_packet) > 0)
2836: return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2837: return 0;
2838: }
2839:
2840: const u_char *
2841: sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2842: {
2843: if (lenp != NULL)
2844: *lenp = sshbuf_len(ssh->state->incoming_packet);
2845: return sshbuf_ptr(ssh->state->incoming_packet);
2846: }
2847:
2848: /* start a new packet */
2849:
2850: int
2851: sshpkt_start(struct ssh *ssh, u_char type)
2852: {
2853: u_char buf[9];
2854: int len;
2855:
2856: DBG(debug("packet_start[%d]", type));
2857: len = compat20 ? 6 : 9;
2858: memset(buf, 0, len - 1);
2859: buf[len - 1] = type;
2860: sshbuf_reset(ssh->state->outgoing_packet);
2861: return sshbuf_put(ssh->state->outgoing_packet, buf, len);
2862: }
2863:
2864: /* send it */
2865:
2866: int
2867: sshpkt_send(struct ssh *ssh)
2868: {
2869: if (compat20)
2870: return ssh_packet_send2(ssh);
2871: else
2872: return ssh_packet_send1(ssh);
2873: }
2874:
2875: int
2876: sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2877: {
2878: char buf[1024];
2879: va_list args;
2880: int r;
2881:
2882: va_start(args, fmt);
2883: vsnprintf(buf, sizeof(buf), fmt, args);
2884: va_end(args);
2885:
2886: if (compat20) {
2887: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2888: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2889: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2890: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2891: (r = sshpkt_send(ssh)) != 0)
2892: return r;
2893: } else {
2894: if ((r = sshpkt_start(ssh, SSH_MSG_DISCONNECT)) != 0 ||
2895: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2896: (r = sshpkt_send(ssh)) != 0)
2897: return r;
1.166 andreas 2898: }
1.201 markus 2899: return 0;
2900: }
2901:
2902: /* roundup current message to pad bytes */
2903: int
2904: sshpkt_add_padding(struct ssh *ssh, u_char pad)
2905: {
2906: ssh->state->extra_pad = pad;
2907: return 0;
1.1 deraadt 2908: }
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