Annotation of src/usr.bin/ssh/packet.c, Revision 1.219
1.219 ! mmcc 1: /* $OpenBSD: packet.c,v 1.218 2015/12/04 16:41:28 markus 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));
1.219 ! mmcc 511: free(ssh->remote_ipaddr);
! 512: ssh->remote_ipaddr = NULL;
1.201 markus 513: free(ssh->state);
514: ssh->state = NULL;
1.1 deraadt 515: }
516:
517: /* Sets remote side protocol flags. */
518:
1.2 provos 519: void
1.201 markus 520: ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
1.1 deraadt 521: {
1.201 markus 522: ssh->state->remote_protocol_flags = protocol_flags;
1.1 deraadt 523: }
524:
525: /* Returns the remote protocol flags set earlier by the above function. */
526:
1.40 markus 527: u_int
1.201 markus 528: ssh_packet_get_protocol_flags(struct ssh *ssh)
1.1 deraadt 529: {
1.201 markus 530: return ssh->state->remote_protocol_flags;
1.1 deraadt 531: }
532:
1.16 markus 533: /*
534: * Starts packet compression from the next packet on in both directions.
535: * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
536: */
1.1 deraadt 537:
1.201 markus 538: static int
539: ssh_packet_init_compression(struct ssh *ssh)
1.60 markus 540: {
1.201 markus 541: if (!ssh->state->compression_buffer &&
542: ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
543: return SSH_ERR_ALLOC_FAIL;
544: return 0;
1.60 markus 545: }
546:
1.201 markus 547: static int
548: start_compression_out(struct ssh *ssh, int level)
1.1 deraadt 549: {
1.201 markus 550: if (level < 1 || level > 9)
551: return SSH_ERR_INVALID_ARGUMENT;
552: debug("Enabling compression at level %d.", level);
553: if (ssh->state->compression_out_started == 1)
554: deflateEnd(&ssh->state->compression_out_stream);
555: switch (deflateInit(&ssh->state->compression_out_stream, level)) {
556: case Z_OK:
557: ssh->state->compression_out_started = 1;
558: break;
559: case Z_MEM_ERROR:
560: return SSH_ERR_ALLOC_FAIL;
561: default:
562: return SSH_ERR_INTERNAL_ERROR;
563: }
564: return 0;
1.1 deraadt 565: }
566:
1.201 markus 567: static int
568: start_compression_in(struct ssh *ssh)
569: {
570: if (ssh->state->compression_in_started == 1)
571: inflateEnd(&ssh->state->compression_in_stream);
572: switch (inflateInit(&ssh->state->compression_in_stream)) {
573: case Z_OK:
574: ssh->state->compression_in_started = 1;
575: break;
576: case Z_MEM_ERROR:
577: return SSH_ERR_ALLOC_FAIL;
578: default:
579: return SSH_ERR_INTERNAL_ERROR;
580: }
581: return 0;
582: }
1.95 markus 583:
1.201 markus 584: int
585: ssh_packet_start_compression(struct ssh *ssh, int level)
1.1 deraadt 586: {
1.197 djm 587: int r;
1.97 deraadt 588:
1.201 markus 589: if (ssh->state->packet_compression && !compat20)
590: return SSH_ERR_INTERNAL_ERROR;
591: ssh->state->packet_compression = 1;
592: if ((r = ssh_packet_init_compression(ssh)) != 0 ||
593: (r = start_compression_in(ssh)) != 0 ||
594: (r = start_compression_out(ssh, level)) != 0)
595: return r;
596: return 0;
1.95 markus 597: }
598:
1.201 markus 599: /* XXX remove need for separate compression buffer */
600: static int
601: compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.95 markus 602: {
1.201 markus 603: u_char buf[4096];
604: int r, status;
605:
606: if (ssh->state->compression_out_started != 1)
607: return SSH_ERR_INTERNAL_ERROR;
608:
609: /* This case is not handled below. */
610: if (sshbuf_len(in) == 0)
611: return 0;
612:
613: /* Input is the contents of the input buffer. */
614: if ((ssh->state->compression_out_stream.next_in =
615: sshbuf_mutable_ptr(in)) == NULL)
616: return SSH_ERR_INTERNAL_ERROR;
617: ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
618:
619: /* Loop compressing until deflate() returns with avail_out != 0. */
620: do {
621: /* Set up fixed-size output buffer. */
622: ssh->state->compression_out_stream.next_out = buf;
623: ssh->state->compression_out_stream.avail_out = sizeof(buf);
624:
625: /* Compress as much data into the buffer as possible. */
626: status = deflate(&ssh->state->compression_out_stream,
627: Z_PARTIAL_FLUSH);
628: switch (status) {
629: case Z_MEM_ERROR:
630: return SSH_ERR_ALLOC_FAIL;
631: case Z_OK:
632: /* Append compressed data to output_buffer. */
633: if ((r = sshbuf_put(out, buf, sizeof(buf) -
634: ssh->state->compression_out_stream.avail_out)) != 0)
635: return r;
636: break;
637: case Z_STREAM_ERROR:
638: default:
639: ssh->state->compression_out_failures++;
640: return SSH_ERR_INVALID_FORMAT;
641: }
642: } while (ssh->state->compression_out_stream.avail_out == 0);
643: return 0;
1.1 deraadt 644: }
645:
1.201 markus 646: static int
647: uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.1 deraadt 648: {
1.201 markus 649: u_char buf[4096];
650: int r, status;
1.1 deraadt 651:
1.201 markus 652: if (ssh->state->compression_in_started != 1)
653: return SSH_ERR_INTERNAL_ERROR;
1.25 markus 654:
1.201 markus 655: if ((ssh->state->compression_in_stream.next_in =
656: sshbuf_mutable_ptr(in)) == NULL)
657: return SSH_ERR_INTERNAL_ERROR;
658: ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
1.97 deraadt 659:
1.201 markus 660: for (;;) {
661: /* Set up fixed-size output buffer. */
662: ssh->state->compression_in_stream.next_out = buf;
663: ssh->state->compression_in_stream.avail_out = sizeof(buf);
664:
665: status = inflate(&ssh->state->compression_in_stream,
666: Z_PARTIAL_FLUSH);
667: switch (status) {
668: case Z_OK:
669: if ((r = sshbuf_put(out, buf, sizeof(buf) -
670: ssh->state->compression_in_stream.avail_out)) != 0)
671: return r;
672: break;
673: case Z_BUF_ERROR:
674: /*
675: * Comments in zlib.h say that we should keep calling
676: * inflate() until we get an error. This appears to
677: * be the error that we get.
678: */
679: return 0;
680: case Z_DATA_ERROR:
681: return SSH_ERR_INVALID_FORMAT;
682: case Z_MEM_ERROR:
683: return SSH_ERR_ALLOC_FAIL;
684: case Z_STREAM_ERROR:
685: default:
686: ssh->state->compression_in_failures++;
687: return SSH_ERR_INTERNAL_ERROR;
688: }
689: }
690: /* NOTREACHED */
1.1 deraadt 691: }
1.125 deraadt 692:
1.201 markus 693: /* Serialise compression state into a blob for privsep */
694: static int
695: ssh_packet_get_compress_state(struct sshbuf *m, struct ssh *ssh)
1.1 deraadt 696: {
1.201 markus 697: struct session_state *state = ssh->state;
698: struct sshbuf *b;
699: int r;
700:
701: if ((b = sshbuf_new()) == NULL)
702: return SSH_ERR_ALLOC_FAIL;
703: if (state->compression_in_started) {
704: if ((r = sshbuf_put_string(b, &state->compression_in_stream,
705: sizeof(state->compression_in_stream))) != 0)
706: goto out;
707: } else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
708: goto out;
709: if (state->compression_out_started) {
710: if ((r = sshbuf_put_string(b, &state->compression_out_stream,
711: sizeof(state->compression_out_stream))) != 0)
712: goto out;
713: } else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
714: goto out;
715: r = sshbuf_put_stringb(m, b);
716: out:
717: sshbuf_free(b);
718: return r;
1.1 deraadt 719: }
1.125 deraadt 720:
1.201 markus 721: /* Deserialise compression state from a blob for privsep */
722: static int
723: ssh_packet_set_compress_state(struct ssh *ssh, struct sshbuf *m)
1.162 andreas 724: {
1.201 markus 725: struct session_state *state = ssh->state;
726: struct sshbuf *b = NULL;
727: int r;
728: const u_char *inblob, *outblob;
729: size_t inl, outl;
1.162 andreas 730:
1.201 markus 731: if ((r = sshbuf_froms(m, &b)) != 0)
732: goto out;
733: if ((r = sshbuf_get_string_direct(b, &inblob, &inl)) != 0 ||
734: (r = sshbuf_get_string_direct(b, &outblob, &outl)) != 0)
735: goto out;
736: if (inl == 0)
737: state->compression_in_started = 0;
738: else if (inl != sizeof(state->compression_in_stream)) {
739: r = SSH_ERR_INTERNAL_ERROR;
740: goto out;
741: } else {
742: state->compression_in_started = 1;
743: memcpy(&state->compression_in_stream, inblob, inl);
744: }
745: if (outl == 0)
746: state->compression_out_started = 0;
747: else if (outl != sizeof(state->compression_out_stream)) {
748: r = SSH_ERR_INTERNAL_ERROR;
749: goto out;
750: } else {
751: state->compression_out_started = 1;
752: memcpy(&state->compression_out_stream, outblob, outl);
753: }
754: r = 0;
755: out:
756: sshbuf_free(b);
757: return r;
1.1 deraadt 758: }
1.125 deraadt 759:
1.24 markus 760: void
1.201 markus 761: ssh_packet_set_compress_hooks(struct ssh *ssh, void *ctx,
762: void *(*allocfunc)(void *, u_int, u_int),
763: void (*freefunc)(void *, void *))
764: {
765: ssh->state->compression_out_stream.zalloc = (alloc_func)allocfunc;
766: ssh->state->compression_out_stream.zfree = (free_func)freefunc;
767: ssh->state->compression_out_stream.opaque = ctx;
768: ssh->state->compression_in_stream.zalloc = (alloc_func)allocfunc;
769: ssh->state->compression_in_stream.zfree = (free_func)freefunc;
770: ssh->state->compression_in_stream.opaque = ctx;
1.24 markus 771: }
1.125 deraadt 772:
1.201 markus 773: /*
774: * Causes any further packets to be encrypted using the given key. The same
775: * key is used for both sending and reception. However, both directions are
776: * encrypted independently of each other.
777: */
1.125 deraadt 778:
1.2 provos 779: void
1.201 markus 780: ssh_packet_set_encryption_key(struct ssh *ssh, const u_char *key, u_int keylen, int number)
1.1 deraadt 781: {
1.211 djm 782: #ifndef WITH_SSH1
783: fatal("no SSH protocol 1 support");
784: #else /* WITH_SSH1 */
1.201 markus 785: struct session_state *state = ssh->state;
786: const struct sshcipher *cipher = cipher_by_number(number);
787: int r;
788: const char *wmsg;
1.125 deraadt 789:
1.201 markus 790: if (cipher == NULL)
791: fatal("%s: unknown cipher number %d", __func__, number);
792: if (keylen < 20)
793: fatal("%s: keylen too small: %d", __func__, keylen);
794: if (keylen > SSH_SESSION_KEY_LENGTH)
795: fatal("%s: keylen too big: %d", __func__, keylen);
796: memcpy(state->ssh1_key, key, keylen);
797: state->ssh1_keylen = keylen;
798: if ((r = cipher_init(&state->send_context, cipher, key, keylen,
799: NULL, 0, CIPHER_ENCRYPT)) != 0 ||
800: (r = cipher_init(&state->receive_context, cipher, key, keylen,
801: NULL, 0, CIPHER_DECRYPT) != 0))
802: fatal("%s: cipher_init failed: %s", __func__, ssh_err(r));
803: if (!state->cipher_warning_done &&
804: ((wmsg = cipher_warning_message(&state->send_context)) != NULL ||
805: (wmsg = cipher_warning_message(&state->send_context)) != NULL)) {
806: error("Warning: %s", wmsg);
807: state->cipher_warning_done = 1;
808: }
1.211 djm 809: #endif /* WITH_SSH1 */
1.170 djm 810: }
811:
1.16 markus 812: /*
813: * Finalizes and sends the packet. If the encryption key has been set,
814: * encrypts the packet before sending.
815: */
1.14 markus 816:
1.201 markus 817: int
818: ssh_packet_send1(struct ssh *ssh)
1.1 deraadt 819: {
1.201 markus 820: struct session_state *state = ssh->state;
1.89 markus 821: u_char buf[8], *cp;
1.201 markus 822: int r, padding, len;
1.40 markus 823: u_int checksum;
1.14 markus 824:
1.16 markus 825: /*
826: * If using packet compression, compress the payload of the outgoing
827: * packet.
828: */
1.201 markus 829: if (state->packet_compression) {
830: sshbuf_reset(state->compression_buffer);
1.14 markus 831: /* Skip padding. */
1.201 markus 832: if ((r = sshbuf_consume(state->outgoing_packet, 8)) != 0)
833: goto out;
1.14 markus 834: /* padding */
1.201 markus 835: if ((r = sshbuf_put(state->compression_buffer,
836: "\0\0\0\0\0\0\0\0", 8)) != 0)
837: goto out;
838: if ((r = compress_buffer(ssh, state->outgoing_packet,
839: state->compression_buffer)) != 0)
840: goto out;
841: sshbuf_reset(state->outgoing_packet);
842: if ((r = sshbuf_putb(state->outgoing_packet,
843: state->compression_buffer)) != 0)
844: goto out;
1.14 markus 845: }
846: /* Compute packet length without padding (add checksum, remove padding). */
1.201 markus 847: len = sshbuf_len(state->outgoing_packet) + 4 - 8;
1.14 markus 848:
1.32 markus 849: /* Insert padding. Initialized to zero in packet_start1() */
1.14 markus 850: padding = 8 - len % 8;
1.201 markus 851: if (!state->send_context.plaintext) {
852: cp = sshbuf_mutable_ptr(state->outgoing_packet);
853: if (cp == NULL) {
854: r = SSH_ERR_INTERNAL_ERROR;
855: goto out;
1.14 markus 856: }
1.201 markus 857: arc4random_buf(cp + 8 - padding, padding);
1.14 markus 858: }
1.201 markus 859: if ((r = sshbuf_consume(state->outgoing_packet, 8 - padding)) != 0)
860: goto out;
1.14 markus 861:
862: /* Add check bytes. */
1.201 markus 863: checksum = ssh_crc32(sshbuf_ptr(state->outgoing_packet),
864: sshbuf_len(state->outgoing_packet));
865: POKE_U32(buf, checksum);
866: if ((r = sshbuf_put(state->outgoing_packet, buf, 4)) != 0)
867: goto out;
1.1 deraadt 868:
869: #ifdef PACKET_DEBUG
1.14 markus 870: fprintf(stderr, "packet_send plain: ");
1.201 markus 871: sshbuf_dump(state->outgoing_packet, stderr);
1.1 deraadt 872: #endif
873:
1.14 markus 874: /* Append to output. */
1.201 markus 875: POKE_U32(buf, len);
876: if ((r = sshbuf_put(state->output, buf, 4)) != 0)
877: goto out;
878: if ((r = sshbuf_reserve(state->output,
879: sshbuf_len(state->outgoing_packet), &cp)) != 0)
880: goto out;
881: if ((r = cipher_crypt(&state->send_context, 0, cp,
882: sshbuf_ptr(state->outgoing_packet),
883: sshbuf_len(state->outgoing_packet), 0, 0)) != 0)
884: goto out;
1.14 markus 885:
1.1 deraadt 886: #ifdef PACKET_DEBUG
1.14 markus 887: fprintf(stderr, "encrypted: ");
1.201 markus 888: sshbuf_dump(state->output, stderr);
1.1 deraadt 889: #endif
1.201 markus 890: state->p_send.packets++;
891: state->p_send.bytes += len +
892: sshbuf_len(state->outgoing_packet);
893: sshbuf_reset(state->outgoing_packet);
1.1 deraadt 894:
1.16 markus 895: /*
1.120 djm 896: * Note that the packet is now only buffered in output. It won't be
1.205 djm 897: * actually sent until ssh_packet_write_wait or ssh_packet_write_poll
898: * is called.
1.16 markus 899: */
1.201 markus 900: r = 0;
901: out:
902: return r;
1.1 deraadt 903: }
904:
1.201 markus 905: int
906: ssh_set_newkeys(struct ssh *ssh, int mode)
1.57 markus 907: {
1.201 markus 908: struct session_state *state = ssh->state;
909: struct sshenc *enc;
910: struct sshmac *mac;
911: struct sshcomp *comp;
912: struct sshcipher_ctx *cc;
1.105 markus 913: u_int64_t *max_blocks;
1.201 markus 914: const char *wmsg;
1.197 djm 915: int r, crypt_type;
1.57 markus 916:
1.100 markus 917: debug2("set_newkeys: mode %d", mode);
1.57 markus 918:
1.88 markus 919: if (mode == MODE_OUT) {
1.201 markus 920: cc = &state->send_context;
1.115 avsm 921: crypt_type = CIPHER_ENCRYPT;
1.201 markus 922: state->p_send.packets = state->p_send.blocks = 0;
923: max_blocks = &state->max_blocks_out;
1.88 markus 924: } else {
1.201 markus 925: cc = &state->receive_context;
1.115 avsm 926: crypt_type = CIPHER_DECRYPT;
1.201 markus 927: state->p_read.packets = state->p_read.blocks = 0;
928: max_blocks = &state->max_blocks_in;
1.88 markus 929: }
1.201 markus 930: if (state->newkeys[mode] != NULL) {
1.100 markus 931: debug("set_newkeys: rekeying");
1.201 markus 932: if ((r = cipher_cleanup(cc)) != 0)
933: return r;
934: enc = &state->newkeys[mode]->enc;
935: mac = &state->newkeys[mode]->mac;
936: comp = &state->newkeys[mode]->comp;
1.148 pvalchev 937: mac_clear(mac);
1.192 djm 938: explicit_bzero(enc->iv, enc->iv_len);
939: explicit_bzero(enc->key, enc->key_len);
940: explicit_bzero(mac->key, mac->key_len);
1.186 djm 941: free(enc->name);
942: free(enc->iv);
943: free(enc->key);
944: free(mac->name);
945: free(mac->key);
946: free(comp->name);
1.201 markus 947: free(state->newkeys[mode]);
1.57 markus 948: }
1.201 markus 949: /* move newkeys from kex to state */
950: if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
951: return SSH_ERR_INTERNAL_ERROR;
952: ssh->kex->newkeys[mode] = NULL;
953: enc = &state->newkeys[mode]->enc;
954: mac = &state->newkeys[mode]->mac;
955: comp = &state->newkeys[mode]->comp;
956: if (cipher_authlen(enc->cipher) == 0) {
957: if ((r = mac_init(mac)) != 0)
958: return r;
959: }
960: mac->enabled = 1;
1.57 markus 961: DBG(debug("cipher_init_context: %d", mode));
1.197 djm 962: if ((r = cipher_init(cc, enc->cipher, enc->key, enc->key_len,
963: enc->iv, enc->iv_len, crypt_type)) != 0)
1.201 markus 964: return r;
965: if (!state->cipher_warning_done &&
966: (wmsg = cipher_warning_message(cc)) != NULL) {
967: error("Warning: %s", wmsg);
968: state->cipher_warning_done = 1;
969: }
1.91 markus 970: /* Deleting the keys does not gain extra security */
1.192 djm 971: /* explicit_bzero(enc->iv, enc->block_size);
972: explicit_bzero(enc->key, enc->key_len);
973: explicit_bzero(mac->key, mac->key_len); */
1.118 markus 974: if ((comp->type == COMP_ZLIB ||
1.161 andreas 975: (comp->type == COMP_DELAYED &&
1.201 markus 976: state->after_authentication)) && comp->enabled == 0) {
977: if ((r = ssh_packet_init_compression(ssh)) < 0)
978: return r;
979: if (mode == MODE_OUT) {
980: if ((r = start_compression_out(ssh, 6)) != 0)
981: return r;
982: } else {
983: if ((r = start_compression_in(ssh)) != 0)
984: return r;
985: }
1.57 markus 986: comp->enabled = 1;
987: }
1.109 markus 988: /*
989: * The 2^(blocksize*2) limit is too expensive for 3DES,
990: * blowfish, etc, so enforce a 1GB limit for small blocksizes.
991: */
992: if (enc->block_size >= 16)
993: *max_blocks = (u_int64_t)1 << (enc->block_size*2);
994: else
995: *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1.201 markus 996: if (state->rekey_limit)
1.161 andreas 997: *max_blocks = MIN(*max_blocks,
1.201 markus 998: state->rekey_limit / enc->block_size);
999: return 0;
1.57 markus 1000: }
1001:
1.16 markus 1002: /*
1.118 markus 1003: * Delayed compression for SSH2 is enabled after authentication:
1.143 dtucker 1004: * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1.118 markus 1005: * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
1006: */
1.201 markus 1007: static int
1008: ssh_packet_enable_delayed_compress(struct ssh *ssh)
1.118 markus 1009: {
1.201 markus 1010: struct session_state *state = ssh->state;
1011: struct sshcomp *comp = NULL;
1012: int r, mode;
1.118 markus 1013:
1014: /*
1015: * Remember that we are past the authentication step, so rekeying
1016: * with COMP_DELAYED will turn on compression immediately.
1017: */
1.201 markus 1018: state->after_authentication = 1;
1.118 markus 1019: for (mode = 0; mode < MODE_MAX; mode++) {
1.145 markus 1020: /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1.201 markus 1021: if (state->newkeys[mode] == NULL)
1.145 markus 1022: continue;
1.201 markus 1023: comp = &state->newkeys[mode]->comp;
1.118 markus 1024: if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1.201 markus 1025: if ((r = ssh_packet_init_compression(ssh)) != 0)
1026: return r;
1027: if (mode == MODE_OUT) {
1028: if ((r = start_compression_out(ssh, 6)) != 0)
1029: return r;
1030: } else {
1031: if ((r = start_compression_in(ssh)) != 0)
1032: return r;
1033: }
1.118 markus 1034: comp->enabled = 1;
1035: }
1036: }
1.201 markus 1037: return 0;
1.118 markus 1038: }
1039:
1040: /*
1.25 markus 1041: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1042: */
1.201 markus 1043: int
1044: ssh_packet_send2_wrapped(struct ssh *ssh)
1.25 markus 1045: {
1.201 markus 1046: struct session_state *state = ssh->state;
1.200 markus 1047: u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1.178 markus 1048: u_char padlen, pad = 0;
1.201 markus 1049: u_int authlen = 0, aadlen = 0;
1050: u_int len;
1051: struct sshenc *enc = NULL;
1052: struct sshmac *mac = NULL;
1053: struct sshcomp *comp = NULL;
1054: int r, block_size;
1055:
1056: if (state->newkeys[MODE_OUT] != NULL) {
1057: enc = &state->newkeys[MODE_OUT]->enc;
1058: mac = &state->newkeys[MODE_OUT]->mac;
1059: comp = &state->newkeys[MODE_OUT]->comp;
1.180 markus 1060: /* disable mac for authenticated encryption */
1061: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1062: mac = NULL;
1.25 markus 1063: }
1.88 markus 1064: block_size = enc ? enc->block_size : 8;
1.180 markus 1065: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1066:
1.201 markus 1067: type = (sshbuf_ptr(state->outgoing_packet))[5];
1.25 markus 1068:
1069: #ifdef PACKET_DEBUG
1070: fprintf(stderr, "plain: ");
1.201 markus 1071: sshbuf_dump(state->outgoing_packet, stderr);
1.25 markus 1072: #endif
1073:
1074: if (comp && comp->enabled) {
1.201 markus 1075: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1076: /* skip header, compress only payload */
1.201 markus 1077: if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1078: goto out;
1079: sshbuf_reset(state->compression_buffer);
1080: if ((r = compress_buffer(ssh, state->outgoing_packet,
1081: state->compression_buffer)) != 0)
1082: goto out;
1083: sshbuf_reset(state->outgoing_packet);
1084: if ((r = sshbuf_put(state->outgoing_packet,
1085: "\0\0\0\0\0", 5)) != 0 ||
1086: (r = sshbuf_putb(state->outgoing_packet,
1087: state->compression_buffer)) != 0)
1088: goto out;
1089: DBG(debug("compression: raw %d compressed %zd", len,
1090: sshbuf_len(state->outgoing_packet)));
1.25 markus 1091: }
1092:
1093: /* sizeof (packet_len + pad_len + payload) */
1.201 markus 1094: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1095:
1096: /*
1097: * calc size of padding, alloc space, get random data,
1098: * minimum padding is 4 bytes
1099: */
1.178 markus 1100: len -= aadlen; /* packet length is not encrypted for EtM modes */
1.25 markus 1101: padlen = block_size - (len % block_size);
1102: if (padlen < 4)
1103: padlen += block_size;
1.201 markus 1104: if (state->extra_pad) {
1.71 markus 1105: /* will wrap if extra_pad+padlen > 255 */
1.201 markus 1106: state->extra_pad =
1107: roundup(state->extra_pad, block_size);
1108: pad = state->extra_pad -
1109: ((len + padlen) % state->extra_pad);
1.193 djm 1110: DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1.201 markus 1111: __func__, pad, len, padlen, state->extra_pad));
1.71 markus 1112: padlen += pad;
1.201 markus 1113: state->extra_pad = 0;
1.71 markus 1114: }
1.201 markus 1115: if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1116: goto out;
1117: if (enc && !state->send_context.plaintext) {
1.32 markus 1118: /* random padding */
1.201 markus 1119: arc4random_buf(cp, padlen);
1.32 markus 1120: } else {
1121: /* clear padding */
1.192 djm 1122: explicit_bzero(cp, padlen);
1.25 markus 1123: }
1.178 markus 1124: /* sizeof (packet_len + pad_len + payload + padding) */
1.201 markus 1125: len = sshbuf_len(state->outgoing_packet);
1126: cp = sshbuf_mutable_ptr(state->outgoing_packet);
1127: if (cp == NULL) {
1128: r = SSH_ERR_INTERNAL_ERROR;
1129: goto out;
1130: }
1.25 markus 1131: /* packet_length includes payload, padding and padding length field */
1.201 markus 1132: POKE_U32(cp, len - 4);
1.89 markus 1133: cp[4] = padlen;
1.178 markus 1134: DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1135: len, padlen, aadlen));
1.25 markus 1136:
1137: /* compute MAC over seqnr and packet(length fields, payload, padding) */
1.178 markus 1138: if (mac && mac->enabled && !mac->etm) {
1.201 markus 1139: if ((r = mac_compute(mac, state->p_send.seqnr,
1140: sshbuf_ptr(state->outgoing_packet), len,
1.200 markus 1141: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1142: goto out;
1143: DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1.25 markus 1144: }
1145: /* encrypt packet and append to output buffer. */
1.201 markus 1146: if ((r = sshbuf_reserve(state->output,
1147: sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1148: goto out;
1149: if ((r = cipher_crypt(&state->send_context, state->p_send.seqnr, cp,
1150: sshbuf_ptr(state->outgoing_packet),
1151: len - aadlen, aadlen, authlen)) != 0)
1152: goto out;
1.25 markus 1153: /* append unencrypted MAC */
1.178 markus 1154: if (mac && mac->enabled) {
1155: if (mac->etm) {
1156: /* EtM: compute mac over aadlen + cipher text */
1.201 markus 1157: if ((r = mac_compute(mac, state->p_send.seqnr,
1158: cp, len, macbuf, sizeof(macbuf))) != 0)
1159: goto out;
1.178 markus 1160: DBG(debug("done calc MAC(EtM) out #%d",
1.201 markus 1161: state->p_send.seqnr));
1.178 markus 1162: }
1.201 markus 1163: if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1164: goto out;
1.178 markus 1165: }
1.25 markus 1166: #ifdef PACKET_DEBUG
1167: fprintf(stderr, "encrypted: ");
1.201 markus 1168: sshbuf_dump(state->output, stderr);
1.25 markus 1169: #endif
1.29 markus 1170: /* increment sequence number for outgoing packets */
1.201 markus 1171: if (++state->p_send.seqnr == 0)
1.106 itojun 1172: logit("outgoing seqnr wraps around");
1.201 markus 1173: if (++state->p_send.packets == 0)
1174: if (!(ssh->compat & SSH_BUG_NOREKEY))
1175: return SSH_ERR_NEED_REKEY;
1176: state->p_send.blocks += len / block_size;
1177: state->p_send.bytes += len;
1178: sshbuf_reset(state->outgoing_packet);
1.25 markus 1179:
1.57 markus 1180: if (type == SSH2_MSG_NEWKEYS)
1.201 markus 1181: r = ssh_set_newkeys(ssh, MODE_OUT);
1182: else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1183: r = ssh_packet_enable_delayed_compress(ssh);
1184: else
1185: r = 0;
1186: out:
1187: return r;
1.25 markus 1188: }
1189:
1.201 markus 1190: int
1191: ssh_packet_send2(struct ssh *ssh)
1.105 markus 1192: {
1.201 markus 1193: struct session_state *state = ssh->state;
1.105 markus 1194: struct packet *p;
1.201 markus 1195: u_char type;
1196: int r;
1.105 markus 1197:
1.201 markus 1198: type = sshbuf_ptr(state->outgoing_packet)[5];
1.105 markus 1199:
1200: /* during rekeying we can only send key exchange messages */
1.201 markus 1201: if (state->rekeying) {
1.175 markus 1202: if ((type < SSH2_MSG_TRANSPORT_MIN) ||
1203: (type > SSH2_MSG_TRANSPORT_MAX) ||
1204: (type == SSH2_MSG_SERVICE_REQUEST) ||
1.218 markus 1205: (type == SSH2_MSG_SERVICE_ACCEPT) ||
1206: (type == SSH2_MSG_EXT_INFO)) {
1.105 markus 1207: debug("enqueue packet: %u", type);
1.201 markus 1208: p = calloc(1, sizeof(*p));
1209: if (p == NULL)
1210: return SSH_ERR_ALLOC_FAIL;
1.105 markus 1211: p->type = type;
1.201 markus 1212: p->payload = state->outgoing_packet;
1213: TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1214: state->outgoing_packet = sshbuf_new();
1215: if (state->outgoing_packet == NULL)
1216: return SSH_ERR_ALLOC_FAIL;
1217: return 0;
1.105 markus 1218: }
1219: }
1220:
1221: /* rekeying starts with sending KEXINIT */
1222: if (type == SSH2_MSG_KEXINIT)
1.201 markus 1223: state->rekeying = 1;
1.105 markus 1224:
1.201 markus 1225: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1226: return r;
1.105 markus 1227:
1228: /* after a NEWKEYS message we can send the complete queue */
1229: if (type == SSH2_MSG_NEWKEYS) {
1.201 markus 1230: state->rekeying = 0;
1231: state->rekey_time = monotime();
1232: while ((p = TAILQ_FIRST(&state->outgoing))) {
1.105 markus 1233: type = p->type;
1234: debug("dequeue packet: %u", type);
1.201 markus 1235: sshbuf_free(state->outgoing_packet);
1236: state->outgoing_packet = p->payload;
1237: TAILQ_REMOVE(&state->outgoing, p, next);
1.186 djm 1238: free(p);
1.201 markus 1239: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1240: return r;
1.105 markus 1241: }
1242: }
1.201 markus 1243: return 0;
1.25 markus 1244: }
1245:
1246: /*
1.16 markus 1247: * Waits until a packet has been received, and returns its type. Note that
1248: * no other data is processed until this returns, so this function should not
1249: * be used during the interactive session.
1250: */
1.1 deraadt 1251:
1.2 provos 1252: int
1.201 markus 1253: ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.1 deraadt 1254: {
1.201 markus 1255: struct session_state *state = ssh->state;
1256: int len, r, ms_remain, cont;
1.56 millert 1257: fd_set *setp;
1.14 markus 1258: char buf[8192];
1.155 deraadt 1259: struct timeval timeout, start, *timeoutp = NULL;
1260:
1.25 markus 1261: DBG(debug("packet_read()"));
1.14 markus 1262:
1.214 deraadt 1263: setp = calloc(howmany(state->connection_in + 1,
1.161 andreas 1264: NFDBITS), sizeof(fd_mask));
1.201 markus 1265: if (setp == NULL)
1266: return SSH_ERR_ALLOC_FAIL;
1.56 millert 1267:
1.205 djm 1268: /*
1269: * Since we are blocking, ensure that all written packets have
1270: * been sent.
1271: */
1.210 markus 1272: if ((r = ssh_packet_write_wait(ssh)) != 0)
1273: goto out;
1.14 markus 1274:
1275: /* Stay in the loop until we have received a complete packet. */
1276: for (;;) {
1277: /* Try to read a packet from the buffer. */
1.201 markus 1278: r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1279: if (r != 0)
1280: break;
1.62 markus 1281: if (!compat20 && (
1.201 markus 1282: *typep == SSH_SMSG_SUCCESS
1283: || *typep == SSH_SMSG_FAILURE
1284: || *typep == SSH_CMSG_EOF
1285: || *typep == SSH_CMSG_EXIT_CONFIRMATION))
1286: if ((r = sshpkt_get_end(ssh)) != 0)
1287: break;
1.14 markus 1288: /* If we got a packet, return it. */
1.201 markus 1289: if (*typep != SSH_MSG_NONE)
1290: break;
1.16 markus 1291: /*
1292: * Otherwise, wait for some data to arrive, add it to the
1293: * buffer, and try again.
1294: */
1.201 markus 1295: memset(setp, 0, howmany(state->connection_in + 1,
1.161 andreas 1296: NFDBITS) * sizeof(fd_mask));
1.201 markus 1297: FD_SET(state->connection_in, setp);
1.16 markus 1298:
1.201 markus 1299: if (state->packet_timeout_ms > 0) {
1300: ms_remain = state->packet_timeout_ms;
1.154 dtucker 1301: timeoutp = &timeout;
1302: }
1.14 markus 1303: /* Wait for some data to arrive. */
1.154 dtucker 1304: for (;;) {
1.201 markus 1305: if (state->packet_timeout_ms != -1) {
1.154 dtucker 1306: ms_to_timeval(&timeout, ms_remain);
1307: gettimeofday(&start, NULL);
1308: }
1.201 markus 1309: if ((r = select(state->connection_in + 1, setp,
1.161 andreas 1310: NULL, NULL, timeoutp)) >= 0)
1.154 dtucker 1311: break;
1.161 andreas 1312: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 1313: break;
1.201 markus 1314: if (state->packet_timeout_ms == -1)
1.154 dtucker 1315: continue;
1316: ms_subtract_diff(&start, &ms_remain);
1317: if (ms_remain <= 0) {
1.201 markus 1318: r = 0;
1.154 dtucker 1319: break;
1320: }
1321: }
1.204 djm 1322: if (r == 0)
1323: return SSH_ERR_CONN_TIMEOUT;
1.14 markus 1324: /* Read data from the socket. */
1.163 andreas 1325: do {
1326: cont = 0;
1.201 markus 1327: len = roaming_read(state->connection_in, buf,
1.163 andreas 1328: sizeof(buf), &cont);
1329: } while (len == 0 && cont);
1.210 markus 1330: if (len == 0) {
1331: r = SSH_ERR_CONN_CLOSED;
1332: goto out;
1333: }
1334: if (len < 0) {
1335: r = SSH_ERR_SYSTEM_ERROR;
1336: goto out;
1337: }
1.204 djm 1338:
1.14 markus 1339: /* Append it to the buffer. */
1.204 djm 1340: if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1.210 markus 1341: goto out;
1.14 markus 1342: }
1.210 markus 1343: out:
1.201 markus 1344: free(setp);
1345: return r;
1.1 deraadt 1346: }
1347:
1.77 djm 1348: int
1.201 markus 1349: ssh_packet_read(struct ssh *ssh)
1.77 djm 1350: {
1.201 markus 1351: u_char type;
1352: int r;
1353:
1354: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1355: fatal("%s: %s", __func__, ssh_err(r));
1356: return type;
1.77 djm 1357: }
1358:
1.16 markus 1359: /*
1360: * Waits until a packet has been received, verifies that its type matches
1361: * that given, and gives a fatal error and exits if there is a mismatch.
1362: */
1.1 deraadt 1363:
1.205 djm 1364: int
1365: ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1.1 deraadt 1366: {
1.205 djm 1367: int r;
1368: u_char type;
1.1 deraadt 1369:
1.205 djm 1370: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1371: return r;
1372: if (type != expected_type) {
1373: if ((r = sshpkt_disconnect(ssh,
1.201 markus 1374: "Protocol error: expected packet type %d, got %d",
1.205 djm 1375: expected_type, type)) != 0)
1376: return r;
1377: return SSH_ERR_PROTOCOL_ERROR;
1378: }
1379: return 0;
1.1 deraadt 1380: }
1381:
1382: /* Checks if a full packet is available in the data received so far via
1.14 markus 1383: * packet_process_incoming. If so, reads the packet; otherwise returns
1384: * SSH_MSG_NONE. This does not wait for data from the connection.
1385: *
1.150 dtucker 1386: * SSH_MSG_DISCONNECT is handled specially here. Also,
1387: * SSH_MSG_IGNORE messages are skipped by this function and are never returned
1388: * to higher levels.
1.14 markus 1389: */
1.1 deraadt 1390:
1.201 markus 1391: int
1392: ssh_packet_read_poll1(struct ssh *ssh, u_char *typep)
1.1 deraadt 1393: {
1.201 markus 1394: struct session_state *state = ssh->state;
1.40 markus 1395: u_int len, padded_len;
1.205 djm 1396: const char *emsg;
1.201 markus 1397: const u_char *cp;
1398: u_char *p;
1.40 markus 1399: u_int checksum, stored_checksum;
1.201 markus 1400: int r;
1401:
1402: *typep = SSH_MSG_NONE;
1.14 markus 1403:
1404: /* Check if input size is less than minimum packet size. */
1.201 markus 1405: if (sshbuf_len(state->input) < 4 + 8)
1406: return 0;
1.14 markus 1407: /* Get length of incoming packet. */
1.201 markus 1408: len = PEEK_U32(sshbuf_ptr(state->input));
1.205 djm 1409: if (len < 1 + 2 + 2 || len > 256 * 1024) {
1410: if ((r = sshpkt_disconnect(ssh, "Bad packet length %u",
1411: len)) != 0)
1412: return r;
1413: return SSH_ERR_CONN_CORRUPT;
1414: }
1.14 markus 1415: padded_len = (len + 8) & ~7;
1416:
1417: /* Check if the packet has been entirely received. */
1.201 markus 1418: if (sshbuf_len(state->input) < 4 + padded_len)
1419: return 0;
1.14 markus 1420:
1421: /* The entire packet is in buffer. */
1422:
1423: /* Consume packet length. */
1.201 markus 1424: if ((r = sshbuf_consume(state->input, 4)) != 0)
1425: goto out;
1.14 markus 1426:
1.62 markus 1427: /*
1428: * Cryptographic attack detector for ssh
1429: * (C)1998 CORE-SDI, Buenos Aires Argentina
1430: * Ariel Futoransky(futo@core-sdi.com)
1431: */
1.201 markus 1432: if (!state->receive_context.plaintext) {
1.205 djm 1433: emsg = NULL;
1.201 markus 1434: switch (detect_attack(&state->deattack,
1435: sshbuf_ptr(state->input), padded_len)) {
1436: case DEATTACK_OK:
1437: break;
1.144 djm 1438: case DEATTACK_DETECTED:
1.205 djm 1439: emsg = "crc32 compensation attack detected";
1440: break;
1.144 djm 1441: case DEATTACK_DOS_DETECTED:
1.205 djm 1442: emsg = "deattack denial of service detected";
1443: break;
1.201 markus 1444: default:
1.205 djm 1445: emsg = "deattack error";
1446: break;
1447: }
1448: if (emsg != NULL) {
1449: error("%s", emsg);
1450: if ((r = sshpkt_disconnect(ssh, "%s", emsg)) != 0 ||
1451: (r = ssh_packet_write_wait(ssh)) != 0)
1452: return r;
1453: return SSH_ERR_CONN_CORRUPT;
1.144 djm 1454: }
1455: }
1.62 markus 1456:
1457: /* Decrypt data to incoming_packet. */
1.201 markus 1458: sshbuf_reset(state->incoming_packet);
1459: if ((r = sshbuf_reserve(state->incoming_packet, padded_len, &p)) != 0)
1460: goto out;
1461: if ((r = cipher_crypt(&state->receive_context, 0, p,
1462: sshbuf_ptr(state->input), padded_len, 0, 0)) != 0)
1463: goto out;
1.62 markus 1464:
1.201 markus 1465: if ((r = sshbuf_consume(state->input, padded_len)) != 0)
1466: goto out;
1.1 deraadt 1467:
1468: #ifdef PACKET_DEBUG
1.14 markus 1469: fprintf(stderr, "read_poll plain: ");
1.201 markus 1470: sshbuf_dump(state->incoming_packet, stderr);
1.1 deraadt 1471: #endif
1472:
1.14 markus 1473: /* Compute packet checksum. */
1.201 markus 1474: checksum = ssh_crc32(sshbuf_ptr(state->incoming_packet),
1475: sshbuf_len(state->incoming_packet) - 4);
1.14 markus 1476:
1477: /* Skip padding. */
1.201 markus 1478: if ((r = sshbuf_consume(state->incoming_packet, 8 - len % 8)) != 0)
1479: goto out;
1.14 markus 1480:
1481: /* Test check bytes. */
1.205 djm 1482: if (len != sshbuf_len(state->incoming_packet)) {
1483: error("%s: len %d != sshbuf_len %zd", __func__,
1.201 markus 1484: len, sshbuf_len(state->incoming_packet));
1.205 djm 1485: if ((r = sshpkt_disconnect(ssh, "invalid packet length")) != 0 ||
1486: (r = ssh_packet_write_wait(ssh)) != 0)
1487: return r;
1488: return SSH_ERR_CONN_CORRUPT;
1489: }
1.14 markus 1490:
1.201 markus 1491: cp = sshbuf_ptr(state->incoming_packet) + len - 4;
1492: stored_checksum = PEEK_U32(cp);
1.205 djm 1493: if (checksum != stored_checksum) {
1494: error("Corrupted check bytes on input");
1495: if ((r = sshpkt_disconnect(ssh, "connection corrupted")) != 0 ||
1496: (r = ssh_packet_write_wait(ssh)) != 0)
1497: return r;
1498: return SSH_ERR_CONN_CORRUPT;
1499: }
1.201 markus 1500: if ((r = sshbuf_consume_end(state->incoming_packet, 4)) < 0)
1501: goto out;
1502:
1503: if (state->packet_compression) {
1504: sshbuf_reset(state->compression_buffer);
1505: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1506: state->compression_buffer)) != 0)
1507: goto out;
1508: sshbuf_reset(state->incoming_packet);
1509: if ((r = sshbuf_putb(state->incoming_packet,
1510: state->compression_buffer)) != 0)
1511: goto out;
1512: }
1513: state->p_read.packets++;
1514: state->p_read.bytes += padded_len + 4;
1515: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1516: goto out;
1.205 djm 1517: if (*typep < SSH_MSG_MIN || *typep > SSH_MSG_MAX) {
1518: error("Invalid ssh1 packet type: %d", *typep);
1519: if ((r = sshpkt_disconnect(ssh, "invalid packet type")) != 0 ||
1520: (r = ssh_packet_write_wait(ssh)) != 0)
1521: return r;
1522: return SSH_ERR_PROTOCOL_ERROR;
1523: }
1.201 markus 1524: r = 0;
1525: out:
1526: return r;
1.1 deraadt 1527: }
1.14 markus 1528:
1.201 markus 1529: int
1530: ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1531: {
1.201 markus 1532: struct session_state *state = ssh->state;
1.40 markus 1533: u_int padlen, need;
1.201 markus 1534: u_char *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1535: u_int maclen, aadlen = 0, authlen = 0, block_size;
1536: struct sshenc *enc = NULL;
1537: struct sshmac *mac = NULL;
1538: struct sshcomp *comp = NULL;
1.200 markus 1539: int r;
1.201 markus 1540:
1541: *typep = SSH_MSG_NONE;
1542:
1543: if (state->packet_discard)
1544: return 0;
1545:
1546: if (state->newkeys[MODE_IN] != NULL) {
1547: enc = &state->newkeys[MODE_IN]->enc;
1548: mac = &state->newkeys[MODE_IN]->mac;
1549: comp = &state->newkeys[MODE_IN]->comp;
1.180 markus 1550: /* disable mac for authenticated encryption */
1551: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1552: mac = NULL;
1.25 markus 1553: }
1554: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.88 markus 1555: block_size = enc ? enc->block_size : 8;
1.180 markus 1556: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1557:
1.201 markus 1558: if (aadlen && state->packlen == 0) {
1559: if (cipher_get_length(&state->receive_context,
1560: &state->packlen, state->p_read.seqnr,
1561: sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1562: return 0;
1563: if (state->packlen < 1 + 4 ||
1564: state->packlen > PACKET_MAX_SIZE) {
1.178 markus 1565: #ifdef PACKET_DEBUG
1.201 markus 1566: sshbuf_dump(state->input, stderr);
1.178 markus 1567: #endif
1.201 markus 1568: logit("Bad packet length %u.", state->packlen);
1569: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1570: return r;
1.217 djm 1571: return SSH_ERR_CONN_CORRUPT;
1.178 markus 1572: }
1.201 markus 1573: sshbuf_reset(state->incoming_packet);
1574: } else if (state->packlen == 0) {
1.25 markus 1575: /*
1576: * check if input size is less than the cipher block size,
1577: * decrypt first block and extract length of incoming packet
1578: */
1.201 markus 1579: if (sshbuf_len(state->input) < block_size)
1580: return 0;
1581: sshbuf_reset(state->incoming_packet);
1582: if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1583: &cp)) != 0)
1584: goto out;
1585: if ((r = cipher_crypt(&state->receive_context,
1586: state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1587: block_size, 0, 0)) != 0)
1588: goto out;
1589: state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1590: if (state->packlen < 1 + 4 ||
1591: state->packlen > PACKET_MAX_SIZE) {
1.110 markus 1592: #ifdef PACKET_DEBUG
1.201 markus 1593: fprintf(stderr, "input: \n");
1594: sshbuf_dump(state->input, stderr);
1595: fprintf(stderr, "incoming_packet: \n");
1596: sshbuf_dump(state->incoming_packet, stderr);
1.110 markus 1597: #endif
1.201 markus 1598: logit("Bad packet length %u.", state->packlen);
1599: return ssh_packet_start_discard(ssh, enc, mac,
1600: state->packlen, PACKET_MAX_SIZE);
1.25 markus 1601: }
1.201 markus 1602: if ((r = sshbuf_consume(state->input, block_size)) != 0)
1603: goto out;
1.25 markus 1604: }
1.201 markus 1605: DBG(debug("input: packet len %u", state->packlen+4));
1606:
1.178 markus 1607: if (aadlen) {
1608: /* only the payload is encrypted */
1.201 markus 1609: need = state->packlen;
1.178 markus 1610: } else {
1611: /*
1612: * the payload size and the payload are encrypted, but we
1613: * have a partial packet of block_size bytes
1614: */
1.201 markus 1615: need = 4 + state->packlen - block_size;
1.178 markus 1616: }
1.180 markus 1617: DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1618: " aadlen %d", block_size, need, maclen, authlen, aadlen));
1.158 markus 1619: if (need % block_size != 0) {
1620: logit("padding error: need %d block %d mod %d",
1.25 markus 1621: need, block_size, need % block_size);
1.201 markus 1622: return ssh_packet_start_discard(ssh, enc, mac,
1623: state->packlen, PACKET_MAX_SIZE - block_size);
1.158 markus 1624: }
1.25 markus 1625: /*
1626: * check if the entire packet has been received and
1.178 markus 1627: * decrypt into incoming_packet:
1628: * 'aadlen' bytes are unencrypted, but authenticated.
1.180 markus 1629: * 'need' bytes are encrypted, followed by either
1630: * 'authlen' bytes of authentication tag or
1.178 markus 1631: * 'maclen' bytes of message authentication code.
1.25 markus 1632: */
1.201 markus 1633: if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1634: return 0;
1.25 markus 1635: #ifdef PACKET_DEBUG
1636: fprintf(stderr, "read_poll enc/full: ");
1.201 markus 1637: sshbuf_dump(state->input, stderr);
1.25 markus 1638: #endif
1.178 markus 1639: /* EtM: compute mac over encrypted input */
1.201 markus 1640: if (mac && mac->enabled && mac->etm) {
1641: if ((r = mac_compute(mac, state->p_read.seqnr,
1642: sshbuf_ptr(state->input), aadlen + need,
1.200 markus 1643: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1644: goto out;
1645: }
1646: if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1647: &cp)) != 0)
1648: goto out;
1649: if ((r = cipher_crypt(&state->receive_context, state->p_read.seqnr, cp,
1650: sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1651: goto out;
1652: if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1653: goto out;
1.25 markus 1654: /*
1655: * compute MAC over seqnr and packet,
1656: * increment sequence number for incoming packet
1657: */
1.29 markus 1658: if (mac && mac->enabled) {
1.178 markus 1659: if (!mac->etm)
1.201 markus 1660: if ((r = mac_compute(mac, state->p_read.seqnr,
1661: sshbuf_ptr(state->incoming_packet),
1662: sshbuf_len(state->incoming_packet),
1.200 markus 1663: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1664: goto out;
1665: if (timingsafe_bcmp(macbuf, sshbuf_ptr(state->input),
1.161 andreas 1666: mac->mac_len) != 0) {
1.159 markus 1667: logit("Corrupted MAC on input.");
1668: if (need > PACKET_MAX_SIZE)
1.201 markus 1669: return SSH_ERR_INTERNAL_ERROR;
1670: return ssh_packet_start_discard(ssh, enc, mac,
1671: state->packlen, PACKET_MAX_SIZE - need);
1672: }
1673:
1674: DBG(debug("MAC #%d ok", state->p_read.seqnr));
1675: if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1676: goto out;
1.25 markus 1677: }
1.77 djm 1678: if (seqnr_p != NULL)
1.201 markus 1679: *seqnr_p = state->p_read.seqnr;
1680: if (++state->p_read.seqnr == 0)
1.106 itojun 1681: logit("incoming seqnr wraps around");
1.201 markus 1682: if (++state->p_read.packets == 0)
1683: if (!(ssh->compat & SSH_BUG_NOREKEY))
1684: return SSH_ERR_NEED_REKEY;
1685: state->p_read.blocks += (state->packlen + 4) / block_size;
1686: state->p_read.bytes += state->packlen + 4;
1.25 markus 1687:
1688: /* get padlen */
1.201 markus 1689: padlen = sshbuf_ptr(state->incoming_packet)[4];
1.25 markus 1690: DBG(debug("input: padlen %d", padlen));
1.205 djm 1691: if (padlen < 4) {
1692: if ((r = sshpkt_disconnect(ssh,
1693: "Corrupted padlen %d on input.", padlen)) != 0 ||
1694: (r = ssh_packet_write_wait(ssh)) != 0)
1695: return r;
1696: return SSH_ERR_CONN_CORRUPT;
1697: }
1.25 markus 1698:
1699: /* skip packet size + padlen, discard padding */
1.201 markus 1700: if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1701: ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1702: goto out;
1.25 markus 1703:
1.201 markus 1704: DBG(debug("input: len before de-compress %zd",
1705: sshbuf_len(state->incoming_packet)));
1.25 markus 1706: if (comp && comp->enabled) {
1.201 markus 1707: sshbuf_reset(state->compression_buffer);
1708: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1709: state->compression_buffer)) != 0)
1710: goto out;
1711: sshbuf_reset(state->incoming_packet);
1712: if ((r = sshbuf_putb(state->incoming_packet,
1713: state->compression_buffer)) != 0)
1714: goto out;
1715: DBG(debug("input: len after de-compress %zd",
1716: sshbuf_len(state->incoming_packet)));
1.25 markus 1717: }
1718: /*
1719: * get packet type, implies consume.
1720: * return length of payload (without type field)
1721: */
1.201 markus 1722: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1723: goto out;
1.205 djm 1724: if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1725: if ((r = sshpkt_disconnect(ssh,
1726: "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1727: (r = ssh_packet_write_wait(ssh)) != 0)
1728: return r;
1729: return SSH_ERR_PROTOCOL_ERROR;
1730: }
1.201 markus 1731: if (*typep == SSH2_MSG_NEWKEYS)
1732: r = ssh_set_newkeys(ssh, MODE_IN);
1733: else if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1734: r = ssh_packet_enable_delayed_compress(ssh);
1735: else
1736: r = 0;
1.25 markus 1737: #ifdef PACKET_DEBUG
1.201 markus 1738: fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1739: sshbuf_dump(state->incoming_packet, stderr);
1.25 markus 1740: #endif
1.62 markus 1741: /* reset for next packet */
1.201 markus 1742: state->packlen = 0;
1743: out:
1744: return r;
1.25 markus 1745: }
1746:
1747: int
1.201 markus 1748: ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1749: {
1.201 markus 1750: struct session_state *state = ssh->state;
1.96 deraadt 1751: u_int reason, seqnr;
1.201 markus 1752: int r;
1753: u_char *msg;
1.62 markus 1754:
1.25 markus 1755: for (;;) {
1.201 markus 1756: msg = NULL;
1.62 markus 1757: if (compat20) {
1.201 markus 1758: r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1759: if (r != 0)
1760: return r;
1761: if (*typep) {
1762: state->keep_alive_timeouts = 0;
1763: DBG(debug("received packet type %d", *typep));
1.153 djm 1764: }
1.201 markus 1765: switch (*typep) {
1.150 dtucker 1766: case SSH2_MSG_IGNORE:
1.151 dtucker 1767: debug3("Received SSH2_MSG_IGNORE");
1.150 dtucker 1768: break;
1.25 markus 1769: case SSH2_MSG_DEBUG:
1.201 markus 1770: if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1771: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1772: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1.219 ! mmcc 1773: free(msg);
1.201 markus 1774: return r;
1775: }
1.25 markus 1776: debug("Remote: %.900s", msg);
1.186 djm 1777: free(msg);
1.25 markus 1778: break;
1779: case SSH2_MSG_DISCONNECT:
1.201 markus 1780: if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1781: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1782: return r;
1.182 djm 1783: /* Ignore normal client exit notifications */
1.201 markus 1784: do_log2(ssh->state->server_side &&
1.182 djm 1785: reason == SSH2_DISCONNECT_BY_APPLICATION ?
1786: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1787: "Received disconnect from %s: %u: %.400s",
1.201 markus 1788: ssh_remote_ipaddr(ssh), reason, msg);
1.186 djm 1789: free(msg);
1.201 markus 1790: return SSH_ERR_DISCONNECTED;
1.84 markus 1791: case SSH2_MSG_UNIMPLEMENTED:
1.201 markus 1792: if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1793: return r;
1.96 deraadt 1794: debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1795: seqnr);
1.150 dtucker 1796: break;
1.25 markus 1797: default:
1.201 markus 1798: return 0;
1.48 stevesk 1799: }
1.25 markus 1800: } else {
1.201 markus 1801: r = ssh_packet_read_poll1(ssh, typep);
1802: switch (*typep) {
1.188 djm 1803: case SSH_MSG_NONE:
1804: return SSH_MSG_NONE;
1.25 markus 1805: case SSH_MSG_IGNORE:
1806: break;
1807: case SSH_MSG_DEBUG:
1.201 markus 1808: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1809: return r;
1.25 markus 1810: debug("Remote: %.900s", msg);
1.186 djm 1811: free(msg);
1.25 markus 1812: break;
1813: case SSH_MSG_DISCONNECT:
1.201 markus 1814: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1815: return r;
1.181 djm 1816: error("Received disconnect from %s: %.400s",
1.201 markus 1817: ssh_remote_ipaddr(ssh), msg);
1818: free(msg);
1819: return SSH_ERR_DISCONNECTED;
1.25 markus 1820: default:
1.201 markus 1821: DBG(debug("received packet type %d", *typep));
1822: return 0;
1.48 stevesk 1823: }
1.25 markus 1824: }
1825: }
1826: }
1827:
1.16 markus 1828: /*
1829: * Buffers the given amount of input characters. This is intended to be used
1830: * together with packet_read_poll.
1831: */
1.1 deraadt 1832:
1.204 djm 1833: int
1.201 markus 1834: ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1.1 deraadt 1835: {
1.201 markus 1836: struct session_state *state = ssh->state;
1837: int r;
1838:
1839: if (state->packet_discard) {
1840: state->keep_alive_timeouts = 0; /* ?? */
1841: if (len >= state->packet_discard) {
1842: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1.204 djm 1843: return r;
1.201 markus 1844: }
1845: state->packet_discard -= len;
1.204 djm 1846: return 0;
1.159 markus 1847: }
1.201 markus 1848: if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1.204 djm 1849: return r;
1850:
1851: return 0;
1.28 markus 1852: }
1853:
1854: int
1.201 markus 1855: ssh_packet_remaining(struct ssh *ssh)
1.28 markus 1856: {
1.201 markus 1857: return sshbuf_len(ssh->state->incoming_packet);
1.1 deraadt 1858: }
1859:
1.16 markus 1860: /*
1861: * Sends a diagnostic message from the server to the client. This message
1862: * can be sent at any time (but not while constructing another message). The
1863: * message is printed immediately, but only if the client is being executed
1864: * in verbose mode. These messages are primarily intended to ease debugging
1865: * authentication problems. The length of the formatted message must not
1.205 djm 1866: * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1.16 markus 1867: */
1.2 provos 1868: void
1.201 markus 1869: ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1870: {
1.14 markus 1871: char buf[1024];
1872: va_list args;
1.201 markus 1873: int r;
1.39 markus 1874:
1.201 markus 1875: if (compat20 && (ssh->compat & SSH_BUG_DEBUG))
1.39 markus 1876: return;
1.14 markus 1877:
1878: va_start(args, fmt);
1879: vsnprintf(buf, sizeof(buf), fmt, args);
1880: va_end(args);
1881:
1.30 markus 1882: if (compat20) {
1.201 markus 1883: if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1884: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1885: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1886: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1887: (r = sshpkt_send(ssh)) != 0)
1888: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1889: } else {
1.201 markus 1890: if ((r = sshpkt_start(ssh, SSH_MSG_DEBUG)) != 0 ||
1891: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1892: (r = sshpkt_send(ssh)) != 0)
1893: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1894: }
1.205 djm 1895: if ((r = ssh_packet_write_wait(ssh)) != 0)
1896: fatal("%s: %s", __func__, ssh_err(r));
1897: }
1898:
1899: /*
1900: * Pretty-print connection-terminating errors and exit.
1901: */
1902: void
1903: sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1904: {
1905: switch (r) {
1906: case SSH_ERR_CONN_CLOSED:
1907: logit("Connection closed by %.200s", ssh_remote_ipaddr(ssh));
1908: cleanup_exit(255);
1909: case SSH_ERR_CONN_TIMEOUT:
1.212 djm 1910: logit("Connection to %.200s timed out", ssh_remote_ipaddr(ssh));
1.205 djm 1911: cleanup_exit(255);
1.212 djm 1912: case SSH_ERR_DISCONNECTED:
1913: logit("Disconnected from %.200s",
1914: ssh_remote_ipaddr(ssh));
1915: cleanup_exit(255);
1916: case SSH_ERR_SYSTEM_ERROR:
1917: if (errno == ECONNRESET) {
1918: logit("Connection reset by %.200s",
1919: ssh_remote_ipaddr(ssh));
1920: cleanup_exit(255);
1.213 djm 1921: }
1922: /* FALLTHROUGH */
1923: case SSH_ERR_NO_CIPHER_ALG_MATCH:
1924: case SSH_ERR_NO_MAC_ALG_MATCH:
1925: case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1926: case SSH_ERR_NO_KEX_ALG_MATCH:
1927: case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1928: if (ssh && ssh->kex && ssh->kex->failed_choice) {
1929: fatal("Unable to negotiate with %.200s: %s. "
1930: "Their offer: %s", ssh_remote_ipaddr(ssh),
1931: ssh_err(r), ssh->kex->failed_choice);
1.212 djm 1932: }
1933: /* FALLTHROUGH */
1.205 djm 1934: default:
1935: fatal("%s%sConnection to %.200s: %s",
1936: tag != NULL ? tag : "", tag != NULL ? ": " : "",
1937: ssh_remote_ipaddr(ssh), ssh_err(r));
1938: }
1.1 deraadt 1939: }
1940:
1.16 markus 1941: /*
1942: * Logs the error plus constructs and sends a disconnect packet, closes the
1943: * connection, and exits. This function never returns. The error message
1944: * should not contain a newline. The length of the formatted message must
1945: * not exceed 1024 bytes.
1946: */
1.2 provos 1947: void
1.201 markus 1948: ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1949: {
1.14 markus 1950: char buf[1024];
1951: va_list args;
1952: static int disconnecting = 0;
1.201 markus 1953: int r;
1.97 deraadt 1954:
1.14 markus 1955: if (disconnecting) /* Guard against recursive invocations. */
1956: fatal("packet_disconnect called recursively.");
1957: disconnecting = 1;
1958:
1.16 markus 1959: /*
1960: * Format the message. Note that the caller must make sure the
1961: * message is of limited size.
1962: */
1.14 markus 1963: va_start(args, fmt);
1964: vsnprintf(buf, sizeof(buf), fmt, args);
1965: va_end(args);
1966:
1.99 markus 1967: /* Display the error locally */
1.106 itojun 1968: logit("Disconnecting: %.100s", buf);
1.99 markus 1969:
1.205 djm 1970: /*
1971: * Send the disconnect message to the other side, and wait
1972: * for it to get sent.
1973: */
1974: if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1975: sshpkt_fatal(ssh, __func__, r);
1976:
1977: if ((r = ssh_packet_write_wait(ssh)) != 0)
1978: sshpkt_fatal(ssh, __func__, r);
1.14 markus 1979:
1980: /* Close the connection. */
1.201 markus 1981: ssh_packet_close(ssh);
1.112 markus 1982: cleanup_exit(255);
1.1 deraadt 1983: }
1984:
1.205 djm 1985: /*
1986: * Checks if there is any buffered output, and tries to write some of
1987: * the output.
1988: */
1989: int
1.201 markus 1990: ssh_packet_write_poll(struct ssh *ssh)
1.1 deraadt 1991: {
1.201 markus 1992: struct session_state *state = ssh->state;
1993: int len = sshbuf_len(state->output);
1994: int cont, r;
1.97 deraadt 1995:
1.14 markus 1996: if (len > 0) {
1.163 andreas 1997: cont = 0;
1.201 markus 1998: len = roaming_write(state->connection_out,
1999: sshbuf_ptr(state->output), len, &cont);
1.156 djm 2000: if (len == -1) {
2001: if (errno == EINTR || errno == EAGAIN)
1.205 djm 2002: return 0;
2003: return SSH_ERR_SYSTEM_ERROR;
1.14 markus 2004: }
1.163 andreas 2005: if (len == 0 && !cont)
1.205 djm 2006: return SSH_ERR_CONN_CLOSED;
1.201 markus 2007: if ((r = sshbuf_consume(state->output, len)) != 0)
1.205 djm 2008: return r;
1.14 markus 2009: }
1.205 djm 2010: return 0;
1.1 deraadt 2011: }
2012:
1.16 markus 2013: /*
2014: * Calls packet_write_poll repeatedly until all pending output data has been
2015: * written.
2016: */
1.205 djm 2017: int
1.201 markus 2018: ssh_packet_write_wait(struct ssh *ssh)
1.1 deraadt 2019: {
1.56 millert 2020: fd_set *setp;
1.205 djm 2021: int ret, r, ms_remain = 0;
1.154 dtucker 2022: struct timeval start, timeout, *timeoutp = NULL;
1.201 markus 2023: struct session_state *state = ssh->state;
1.56 millert 2024:
1.214 deraadt 2025: setp = calloc(howmany(state->connection_out + 1,
1.161 andreas 2026: NFDBITS), sizeof(fd_mask));
1.201 markus 2027: if (setp == NULL)
1.205 djm 2028: return SSH_ERR_ALLOC_FAIL;
1.216 gsoares 2029: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2030: free(setp);
1.215 djm 2031: return r;
1.216 gsoares 2032: }
1.201 markus 2033: while (ssh_packet_have_data_to_write(ssh)) {
2034: memset(setp, 0, howmany(state->connection_out + 1,
1.161 andreas 2035: NFDBITS) * sizeof(fd_mask));
1.201 markus 2036: FD_SET(state->connection_out, setp);
1.154 dtucker 2037:
1.201 markus 2038: if (state->packet_timeout_ms > 0) {
2039: ms_remain = state->packet_timeout_ms;
1.154 dtucker 2040: timeoutp = &timeout;
2041: }
2042: for (;;) {
1.201 markus 2043: if (state->packet_timeout_ms != -1) {
1.154 dtucker 2044: ms_to_timeval(&timeout, ms_remain);
2045: gettimeofday(&start, NULL);
2046: }
1.201 markus 2047: if ((ret = select(state->connection_out + 1,
1.161 andreas 2048: NULL, setp, NULL, timeoutp)) >= 0)
1.154 dtucker 2049: break;
1.161 andreas 2050: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 2051: break;
1.201 markus 2052: if (state->packet_timeout_ms == -1)
1.154 dtucker 2053: continue;
2054: ms_subtract_diff(&start, &ms_remain);
2055: if (ms_remain <= 0) {
2056: ret = 0;
2057: break;
2058: }
2059: }
2060: if (ret == 0) {
1.205 djm 2061: free(setp);
2062: return SSH_ERR_CONN_TIMEOUT;
2063: }
2064: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2065: free(setp);
2066: return r;
1.154 dtucker 2067: }
1.14 markus 2068: }
1.186 djm 2069: free(setp);
1.205 djm 2070: return 0;
1.1 deraadt 2071: }
2072:
2073: /* Returns true if there is buffered data to write to the connection. */
2074:
1.2 provos 2075: int
1.201 markus 2076: ssh_packet_have_data_to_write(struct ssh *ssh)
1.1 deraadt 2077: {
1.201 markus 2078: return sshbuf_len(ssh->state->output) != 0;
1.1 deraadt 2079: }
2080:
2081: /* Returns true if there is not too much data to write to the connection. */
2082:
1.2 provos 2083: int
1.201 markus 2084: ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1.1 deraadt 2085: {
1.201 markus 2086: if (ssh->state->interactive_mode)
2087: return sshbuf_len(ssh->state->output) < 16384;
1.14 markus 2088: else
1.201 markus 2089: return sshbuf_len(ssh->state->output) < 128 * 1024;
1.1 deraadt 2090: }
2091:
1.201 markus 2092: void
2093: ssh_packet_set_tos(struct ssh *ssh, int tos)
1.101 markus 2094: {
1.201 markus 2095: if (!ssh_packet_connection_is_on_socket(ssh))
1.101 markus 2096: return;
1.201 markus 2097: switch (ssh_packet_connection_af(ssh)) {
1.173 djm 2098: case AF_INET:
2099: debug3("%s: set IP_TOS 0x%02x", __func__, tos);
1.201 markus 2100: if (setsockopt(ssh->state->connection_in,
1.173 djm 2101: IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2102: error("setsockopt IP_TOS %d: %.100s:",
2103: tos, strerror(errno));
2104: break;
2105: case AF_INET6:
2106: debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
1.201 markus 2107: if (setsockopt(ssh->state->connection_in,
1.173 djm 2108: IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2109: error("setsockopt IPV6_TCLASS %d: %.100s:",
2110: tos, strerror(errno));
2111: break;
2112: }
1.101 markus 2113: }
2114:
1.1 deraadt 2115: /* Informs that the current session is interactive. Sets IP flags for that. */
2116:
1.2 provos 2117: void
1.201 markus 2118: ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
1.1 deraadt 2119: {
1.201 markus 2120: struct session_state *state = ssh->state;
2121:
2122: if (state->set_interactive_called)
1.43 markus 2123: return;
1.201 markus 2124: state->set_interactive_called = 1;
1.1 deraadt 2125:
1.14 markus 2126: /* Record that we are in interactive mode. */
1.201 markus 2127: state->interactive_mode = interactive;
1.1 deraadt 2128:
1.19 markus 2129: /* Only set socket options if using a socket. */
1.201 markus 2130: if (!ssh_packet_connection_is_on_socket(ssh))
1.14 markus 2131: return;
1.201 markus 2132: set_nodelay(state->connection_in);
2133: ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2134: qos_bulk);
1.1 deraadt 2135: }
2136:
2137: /* Returns true if the current connection is interactive. */
2138:
1.2 provos 2139: int
1.201 markus 2140: ssh_packet_is_interactive(struct ssh *ssh)
1.1 deraadt 2141: {
1.201 markus 2142: return ssh->state->interactive_mode;
1.12 markus 2143: }
2144:
1.113 deraadt 2145: int
1.201 markus 2146: ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
1.12 markus 2147: {
1.201 markus 2148: struct session_state *state = ssh->state;
2149:
2150: if (state->set_maxsize_called) {
1.106 itojun 2151: logit("packet_set_maxsize: called twice: old %d new %d",
1.201 markus 2152: state->max_packet_size, s);
1.14 markus 2153: return -1;
2154: }
2155: if (s < 4 * 1024 || s > 1024 * 1024) {
1.106 itojun 2156: logit("packet_set_maxsize: bad size %d", s);
1.14 markus 2157: return -1;
2158: }
1.201 markus 2159: state->set_maxsize_called = 1;
1.66 markus 2160: debug("packet_set_maxsize: setting to %d", s);
1.201 markus 2161: state->max_packet_size = s;
1.14 markus 2162: return s;
1.53 markus 2163: }
2164:
1.161 andreas 2165: int
1.201 markus 2166: ssh_packet_inc_alive_timeouts(struct ssh *ssh)
1.161 andreas 2167: {
1.201 markus 2168: return ++ssh->state->keep_alive_timeouts;
1.161 andreas 2169: }
2170:
2171: void
1.201 markus 2172: ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
1.161 andreas 2173: {
1.201 markus 2174: ssh->state->keep_alive_timeouts = ka;
1.161 andreas 2175: }
2176:
2177: u_int
1.201 markus 2178: ssh_packet_get_maxsize(struct ssh *ssh)
1.71 markus 2179: {
1.201 markus 2180: return ssh->state->max_packet_size;
1.71 markus 2181: }
2182:
1.53 markus 2183: /*
2184: * 9.2. Ignored Data Message
1.61 markus 2185: *
1.53 markus 2186: * byte SSH_MSG_IGNORE
2187: * string data
1.61 markus 2188: *
1.53 markus 2189: * All implementations MUST understand (and ignore) this message at any
2190: * time (after receiving the protocol version). No implementation is
2191: * required to send them. This message can be used as an additional
2192: * protection measure against advanced traffic analysis techniques.
2193: */
1.54 markus 2194: void
1.201 markus 2195: ssh_packet_send_ignore(struct ssh *ssh, int nbytes)
1.54 markus 2196: {
1.115 avsm 2197: u_int32_t rnd = 0;
1.201 markus 2198: int r, i;
1.54 markus 2199:
1.201 markus 2200: if ((r = sshpkt_start(ssh, compat20 ?
2201: SSH2_MSG_IGNORE : SSH_MSG_IGNORE)) != 0 ||
2202: (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2203: fatal("%s: %s", __func__, ssh_err(r));
1.75 deraadt 2204: for (i = 0; i < nbytes; i++) {
1.53 markus 2205: if (i % 4 == 0)
1.115 avsm 2206: rnd = arc4random();
1.201 markus 2207: if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2208: fatal("%s: %s", __func__, ssh_err(r));
1.115 avsm 2209: rnd >>= 8;
1.53 markus 2210: }
1.105 markus 2211: }
2212:
1.113 deraadt 2213: #define MAX_PACKETS (1U<<31)
1.105 markus 2214: int
1.201 markus 2215: ssh_packet_need_rekeying(struct ssh *ssh)
1.105 markus 2216: {
1.201 markus 2217: struct session_state *state = ssh->state;
2218:
2219: if (ssh->compat & SSH_BUG_NOREKEY)
1.105 markus 2220: return 0;
2221: return
1.201 markus 2222: (state->p_send.packets > MAX_PACKETS) ||
2223: (state->p_read.packets > MAX_PACKETS) ||
2224: (state->max_blocks_out &&
2225: (state->p_send.blocks > state->max_blocks_out)) ||
2226: (state->max_blocks_in &&
2227: (state->p_read.blocks > state->max_blocks_in)) ||
2228: (state->rekey_interval != 0 && state->rekey_time +
2229: state->rekey_interval <= monotime());
1.105 markus 2230: }
2231:
2232: void
1.201 markus 2233: ssh_packet_set_rekey_limits(struct ssh *ssh, u_int32_t bytes, time_t seconds)
1.105 markus 2234: {
1.184 dtucker 2235: debug3("rekey after %lld bytes, %d seconds", (long long)bytes,
2236: (int)seconds);
1.201 markus 2237: ssh->state->rekey_limit = bytes;
2238: ssh->state->rekey_interval = seconds;
1.184 dtucker 2239: }
2240:
2241: time_t
1.201 markus 2242: ssh_packet_get_rekey_timeout(struct ssh *ssh)
1.184 dtucker 2243: {
2244: time_t seconds;
2245:
1.201 markus 2246: seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
1.187 dtucker 2247: monotime();
1.185 dtucker 2248: return (seconds <= 0 ? 1 : seconds);
1.118 markus 2249: }
2250:
2251: void
1.201 markus 2252: ssh_packet_set_server(struct ssh *ssh)
1.118 markus 2253: {
1.201 markus 2254: ssh->state->server_side = 1;
1.118 markus 2255: }
2256:
2257: void
1.201 markus 2258: ssh_packet_set_authenticated(struct ssh *ssh)
1.118 markus 2259: {
1.201 markus 2260: ssh->state->after_authentication = 1;
1.161 andreas 2261: }
2262:
2263: void *
1.201 markus 2264: ssh_packet_get_input(struct ssh *ssh)
1.161 andreas 2265: {
1.201 markus 2266: return (void *)ssh->state->input;
1.161 andreas 2267: }
2268:
2269: void *
1.201 markus 2270: ssh_packet_get_output(struct ssh *ssh)
1.161 andreas 2271: {
1.201 markus 2272: return (void *)ssh->state->output;
1.166 andreas 2273: }
2274:
1.201 markus 2275: /* XXX TODO update roaming to new API (does not work anyway) */
1.166 andreas 2276: /*
2277: * Save the state for the real connection, and use a separate state when
2278: * resuming a suspended connection.
2279: */
2280: void
1.201 markus 2281: ssh_packet_backup_state(struct ssh *ssh,
2282: struct ssh *backup_state)
1.166 andreas 2283: {
1.201 markus 2284: struct ssh *tmp;
1.166 andreas 2285:
1.201 markus 2286: close(ssh->state->connection_in);
2287: ssh->state->connection_in = -1;
2288: close(ssh->state->connection_out);
2289: ssh->state->connection_out = -1;
1.166 andreas 2290: if (backup_state)
2291: tmp = backup_state;
2292: else
1.201 markus 2293: tmp = ssh_alloc_session_state();
2294: backup_state = ssh;
2295: ssh = tmp;
1.166 andreas 2296: }
2297:
1.201 markus 2298: /* XXX FIXME FIXME FIXME */
1.166 andreas 2299: /*
2300: * Swap in the old state when resuming a connecion.
2301: */
2302: void
1.201 markus 2303: ssh_packet_restore_state(struct ssh *ssh,
2304: struct ssh *backup_state)
1.166 andreas 2305: {
1.201 markus 2306: struct ssh *tmp;
1.166 andreas 2307: u_int len;
1.201 markus 2308: int r;
1.166 andreas 2309:
2310: tmp = backup_state;
1.201 markus 2311: backup_state = ssh;
2312: ssh = tmp;
2313: ssh->state->connection_in = backup_state->state->connection_in;
2314: backup_state->state->connection_in = -1;
2315: ssh->state->connection_out = backup_state->state->connection_out;
2316: backup_state->state->connection_out = -1;
2317: len = sshbuf_len(backup_state->state->input);
1.166 andreas 2318: if (len > 0) {
1.201 markus 2319: if ((r = sshbuf_putb(ssh->state->input,
2320: backup_state->state->input)) != 0)
2321: fatal("%s: %s", __func__, ssh_err(r));
2322: sshbuf_reset(backup_state->state->input);
1.166 andreas 2323: add_recv_bytes(len);
1.196 markus 2324: }
2325: }
2326:
2327: /* Reset after_authentication and reset compression in post-auth privsep */
1.201 markus 2328: static int
2329: ssh_packet_set_postauth(struct ssh *ssh)
1.196 markus 2330: {
1.201 markus 2331: struct sshcomp *comp;
2332: int r, mode;
1.196 markus 2333:
2334: debug("%s: called", __func__);
2335: /* This was set in net child, but is not visible in user child */
1.201 markus 2336: ssh->state->after_authentication = 1;
2337: ssh->state->rekeying = 0;
1.196 markus 2338: for (mode = 0; mode < MODE_MAX; mode++) {
1.201 markus 2339: if (ssh->state->newkeys[mode] == NULL)
1.196 markus 2340: continue;
1.201 markus 2341: comp = &ssh->state->newkeys[mode]->comp;
2342: if (comp && comp->enabled &&
2343: (r = ssh_packet_init_compression(ssh)) != 0)
2344: return r;
2345: }
2346: return 0;
2347: }
2348:
2349: /* Packet state (de-)serialization for privsep */
2350:
2351: /* turn kex into a blob for packet state serialization */
2352: static int
2353: kex_to_blob(struct sshbuf *m, struct kex *kex)
2354: {
2355: int r;
2356:
2357: if ((r = sshbuf_put_string(m, kex->session_id,
2358: kex->session_id_len)) != 0 ||
2359: (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2360: (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2361: (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2362: (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2363: (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2364: (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2365: (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2366: (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2367: return r;
2368: return 0;
2369: }
2370:
2371: /* turn key exchange results into a blob for packet state serialization */
2372: static int
2373: newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2374: {
2375: struct sshbuf *b;
2376: struct sshcipher_ctx *cc;
2377: struct sshcomp *comp;
2378: struct sshenc *enc;
2379: struct sshmac *mac;
2380: struct newkeys *newkey;
2381: int r;
2382:
2383: if ((newkey = ssh->state->newkeys[mode]) == NULL)
2384: return SSH_ERR_INTERNAL_ERROR;
2385: enc = &newkey->enc;
2386: mac = &newkey->mac;
2387: comp = &newkey->comp;
2388: cc = (mode == MODE_OUT) ? &ssh->state->send_context :
2389: &ssh->state->receive_context;
2390: if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2391: return r;
2392: if ((b = sshbuf_new()) == NULL)
2393: return SSH_ERR_ALLOC_FAIL;
2394: /* The cipher struct is constant and shared, you export pointer */
2395: if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2396: (r = sshbuf_put(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2397: (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2398: (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2399: (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2400: (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2401: goto out;
2402: if (cipher_authlen(enc->cipher) == 0) {
2403: if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2404: (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2405: (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2406: goto out;
2407: }
2408: if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2409: (r = sshbuf_put_u32(b, comp->enabled)) != 0 ||
2410: (r = sshbuf_put_cstring(b, comp->name)) != 0)
2411: goto out;
2412: r = sshbuf_put_stringb(m, b);
2413: out:
2414: if (b != NULL)
2415: sshbuf_free(b);
2416: return r;
2417: }
2418:
2419: /* serialize packet state into a blob */
2420: int
2421: ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2422: {
2423: struct session_state *state = ssh->state;
2424: u_char *p;
2425: size_t slen, rlen;
2426: int r, ssh1cipher;
2427:
2428: if (!compat20) {
2429: ssh1cipher = cipher_get_number(state->receive_context.cipher);
2430: slen = cipher_get_keyiv_len(&state->send_context);
2431: rlen = cipher_get_keyiv_len(&state->receive_context);
2432: if ((r = sshbuf_put_u32(m, state->remote_protocol_flags)) != 0 ||
2433: (r = sshbuf_put_u32(m, ssh1cipher)) != 0 ||
2434: (r = sshbuf_put_string(m, state->ssh1_key, state->ssh1_keylen)) != 0 ||
2435: (r = sshbuf_put_u32(m, slen)) != 0 ||
2436: (r = sshbuf_reserve(m, slen, &p)) != 0 ||
2437: (r = cipher_get_keyiv(&state->send_context, p, slen)) != 0 ||
2438: (r = sshbuf_put_u32(m, rlen)) != 0 ||
2439: (r = sshbuf_reserve(m, rlen, &p)) != 0 ||
2440: (r = cipher_get_keyiv(&state->receive_context, p, rlen)) != 0)
2441: return r;
2442: } else {
2443: if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2444: (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2445: (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
1.208 markus 2446: (r = sshbuf_put_u32(m, state->rekey_limit)) != 0 ||
2447: (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
1.201 markus 2448: (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2449: (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2450: (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2451: (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2452: (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2453: (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2454: (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2455: (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0)
2456: return r;
2457: }
2458:
2459: slen = cipher_get_keycontext(&state->send_context, NULL);
2460: rlen = cipher_get_keycontext(&state->receive_context, NULL);
2461: if ((r = sshbuf_put_u32(m, slen)) != 0 ||
2462: (r = sshbuf_reserve(m, slen, &p)) != 0)
2463: return r;
2464: if (cipher_get_keycontext(&state->send_context, p) != (int)slen)
2465: return SSH_ERR_INTERNAL_ERROR;
2466: if ((r = sshbuf_put_u32(m, rlen)) != 0 ||
2467: (r = sshbuf_reserve(m, rlen, &p)) != 0)
2468: return r;
2469: if (cipher_get_keycontext(&state->receive_context, p) != (int)rlen)
2470: return SSH_ERR_INTERNAL_ERROR;
2471:
2472: if ((r = ssh_packet_get_compress_state(m, ssh)) != 0 ||
2473: (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2474: (r = sshbuf_put_stringb(m, state->output)) != 0)
2475: return r;
2476:
2477: if (compat20) {
2478: if ((r = sshbuf_put_u64(m, get_sent_bytes())) != 0 ||
2479: (r = sshbuf_put_u64(m, get_recv_bytes())) != 0)
2480: return r;
2481: }
2482: return 0;
2483: }
2484:
2485: /* restore key exchange results from blob for packet state de-serialization */
2486: static int
2487: newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2488: {
2489: struct sshbuf *b = NULL;
2490: struct sshcomp *comp;
2491: struct sshenc *enc;
2492: struct sshmac *mac;
2493: struct newkeys *newkey = NULL;
2494: size_t keylen, ivlen, maclen;
2495: int r;
2496:
2497: if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2498: r = SSH_ERR_ALLOC_FAIL;
2499: goto out;
2500: }
2501: if ((r = sshbuf_froms(m, &b)) != 0)
2502: goto out;
2503: #ifdef DEBUG_PK
2504: sshbuf_dump(b, stderr);
2505: #endif
2506: enc = &newkey->enc;
2507: mac = &newkey->mac;
2508: comp = &newkey->comp;
2509:
2510: if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2511: (r = sshbuf_get(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2512: (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2513: (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2514: (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2515: (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2516: goto out;
2517: if (cipher_authlen(enc->cipher) == 0) {
2518: if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2519: goto out;
2520: if ((r = mac_setup(mac, mac->name)) != 0)
2521: goto out;
2522: if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2523: (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2524: goto out;
2525: if (maclen > mac->key_len) {
2526: r = SSH_ERR_INVALID_FORMAT;
2527: goto out;
2528: }
2529: mac->key_len = maclen;
2530: }
2531: if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2532: (r = sshbuf_get_u32(b, (u_int *)&comp->enabled)) != 0 ||
2533: (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2534: goto out;
2535: if (enc->name == NULL ||
2536: cipher_by_name(enc->name) != enc->cipher) {
2537: r = SSH_ERR_INVALID_FORMAT;
2538: goto out;
2539: }
2540: if (sshbuf_len(b) != 0) {
2541: r = SSH_ERR_INVALID_FORMAT;
2542: goto out;
2543: }
2544: enc->key_len = keylen;
2545: enc->iv_len = ivlen;
2546: ssh->kex->newkeys[mode] = newkey;
2547: newkey = NULL;
2548: r = 0;
2549: out:
1.219 ! mmcc 2550: free(newkey);
1.201 markus 2551: if (b != NULL)
2552: sshbuf_free(b);
2553: return r;
2554: }
2555:
2556: /* restore kex from blob for packet state de-serialization */
2557: static int
2558: kex_from_blob(struct sshbuf *m, struct kex **kexp)
2559: {
2560: struct kex *kex;
2561: int r;
2562:
2563: if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2564: (kex->my = sshbuf_new()) == NULL ||
2565: (kex->peer = sshbuf_new()) == NULL) {
2566: r = SSH_ERR_ALLOC_FAIL;
2567: goto out;
2568: }
2569: if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2570: (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2571: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2572: (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2573: (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2574: (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2575: (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2576: (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2577: (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2578: goto out;
2579: kex->server = 1;
2580: kex->done = 1;
2581: r = 0;
2582: out:
2583: if (r != 0 || kexp == NULL) {
2584: if (kex != NULL) {
2585: if (kex->my != NULL)
2586: sshbuf_free(kex->my);
2587: if (kex->peer != NULL)
2588: sshbuf_free(kex->peer);
2589: free(kex);
2590: }
2591: if (kexp != NULL)
2592: *kexp = NULL;
2593: } else {
2594: *kexp = kex;
2595: }
2596: return r;
2597: }
2598:
2599: /*
2600: * Restore packet state from content of blob 'm' (de-serialization).
2601: * Note that 'm' will be partially consumed on parsing or any other errors.
2602: */
2603: int
2604: ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2605: {
2606: struct session_state *state = ssh->state;
2607: const u_char *ssh1key, *ivin, *ivout, *keyin, *keyout, *input, *output;
2608: size_t ssh1keylen, rlen, slen, ilen, olen;
2609: int r;
2610: u_int ssh1cipher = 0;
2611: u_int64_t sent_bytes = 0, recv_bytes = 0;
2612:
2613: if (!compat20) {
2614: if ((r = sshbuf_get_u32(m, &state->remote_protocol_flags)) != 0 ||
2615: (r = sshbuf_get_u32(m, &ssh1cipher)) != 0 ||
2616: (r = sshbuf_get_string_direct(m, &ssh1key, &ssh1keylen)) != 0 ||
2617: (r = sshbuf_get_string_direct(m, &ivout, &slen)) != 0 ||
2618: (r = sshbuf_get_string_direct(m, &ivin, &rlen)) != 0)
2619: return r;
2620: if (ssh1cipher > INT_MAX)
2621: return SSH_ERR_KEY_UNKNOWN_CIPHER;
2622: ssh_packet_set_encryption_key(ssh, ssh1key, ssh1keylen,
2623: (int)ssh1cipher);
2624: if (cipher_get_keyiv_len(&state->send_context) != (int)slen ||
2625: cipher_get_keyiv_len(&state->receive_context) != (int)rlen)
2626: return SSH_ERR_INVALID_FORMAT;
2627: if ((r = cipher_set_keyiv(&state->send_context, ivout)) != 0 ||
2628: (r = cipher_set_keyiv(&state->receive_context, ivin)) != 0)
2629: return r;
2630: } else {
2631: if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2632: (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2633: (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
1.208 markus 2634: (r = sshbuf_get_u32(m, &state->rekey_limit)) != 0 ||
2635: (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
1.201 markus 2636: (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2637: (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2638: (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2639: (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2640: (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2641: (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2642: (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2643: (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2644: return r;
1.208 markus 2645: /*
2646: * We set the time here so that in post-auth privsep slave we
2647: * count from the completion of the authentication.
2648: */
2649: state->rekey_time = monotime();
1.201 markus 2650: /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2651: if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2652: (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2653: return r;
2654: }
2655: if ((r = sshbuf_get_string_direct(m, &keyout, &slen)) != 0 ||
2656: (r = sshbuf_get_string_direct(m, &keyin, &rlen)) != 0)
2657: return r;
2658: if (cipher_get_keycontext(&state->send_context, NULL) != (int)slen ||
2659: cipher_get_keycontext(&state->receive_context, NULL) != (int)rlen)
2660: return SSH_ERR_INVALID_FORMAT;
2661: cipher_set_keycontext(&state->send_context, keyout);
2662: cipher_set_keycontext(&state->receive_context, keyin);
2663:
2664: if ((r = ssh_packet_set_compress_state(ssh, m)) != 0 ||
2665: (r = ssh_packet_set_postauth(ssh)) != 0)
2666: return r;
2667:
2668: sshbuf_reset(state->input);
2669: sshbuf_reset(state->output);
2670: if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2671: (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2672: (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2673: (r = sshbuf_put(state->output, output, olen)) != 0)
2674: return r;
2675:
2676: if (compat20) {
2677: if ((r = sshbuf_get_u64(m, &sent_bytes)) != 0 ||
2678: (r = sshbuf_get_u64(m, &recv_bytes)) != 0)
2679: return r;
2680: roam_set_bytes(sent_bytes, recv_bytes);
2681: }
2682: if (sshbuf_len(m))
2683: return SSH_ERR_INVALID_FORMAT;
2684: debug3("%s: done", __func__);
2685: return 0;
2686: }
2687:
2688: /* NEW API */
2689:
2690: /* put data to the outgoing packet */
2691:
2692: int
2693: sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2694: {
2695: return sshbuf_put(ssh->state->outgoing_packet, v, len);
2696: }
2697:
2698: int
2699: sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2700: {
2701: return sshbuf_putb(ssh->state->outgoing_packet, b);
2702: }
2703:
2704: int
2705: sshpkt_put_u8(struct ssh *ssh, u_char val)
2706: {
2707: return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2708: }
2709:
2710: int
2711: sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2712: {
2713: return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2714: }
2715:
2716: int
2717: sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2718: {
2719: return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2720: }
2721:
2722: int
2723: sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2724: {
2725: return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2726: }
2727:
2728: int
2729: sshpkt_put_cstring(struct ssh *ssh, const void *v)
2730: {
2731: return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2732: }
2733:
2734: int
2735: sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2736: {
2737: return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2738: }
2739:
1.211 djm 2740: #ifdef WITH_OPENSSL
1.201 markus 2741: int
2742: sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2743: {
2744: return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2745: }
2746:
1.211 djm 2747: #ifdef WITH_SSH1
1.201 markus 2748: int
2749: sshpkt_put_bignum1(struct ssh *ssh, const BIGNUM *v)
2750: {
2751: return sshbuf_put_bignum1(ssh->state->outgoing_packet, v);
2752: }
1.211 djm 2753: #endif /* WITH_SSH1 */
1.201 markus 2754:
2755: int
2756: sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2757: {
2758: return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2759: }
1.211 djm 2760: #endif /* WITH_OPENSSL */
1.201 markus 2761:
2762: /* fetch data from the incoming packet */
2763:
2764: int
2765: sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2766: {
2767: return sshbuf_get(ssh->state->incoming_packet, valp, len);
2768: }
2769:
2770: int
2771: sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2772: {
2773: return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2774: }
2775:
2776: int
2777: sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2778: {
2779: return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2780: }
2781:
2782: int
2783: sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2784: {
2785: return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2786: }
2787:
2788: int
2789: sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2790: {
2791: return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2792: }
2793:
2794: int
2795: sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2796: {
2797: return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2798: }
2799:
2800: int
2801: sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2802: {
2803: return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2804: }
2805:
1.211 djm 2806: #ifdef WITH_OPENSSL
1.201 markus 2807: int
2808: sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2809: {
2810: return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2811: }
2812:
1.211 djm 2813: #ifdef WITH_SSH1
1.201 markus 2814: int
2815: sshpkt_get_bignum1(struct ssh *ssh, BIGNUM *v)
2816: {
2817: return sshbuf_get_bignum1(ssh->state->incoming_packet, v);
2818: }
1.211 djm 2819: #endif /* WITH_SSH1 */
1.201 markus 2820:
2821: int
2822: sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2823: {
2824: return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2825: }
1.211 djm 2826: #endif /* WITH_OPENSSL */
1.201 markus 2827:
2828: int
2829: sshpkt_get_end(struct ssh *ssh)
2830: {
2831: if (sshbuf_len(ssh->state->incoming_packet) > 0)
2832: return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2833: return 0;
2834: }
2835:
2836: const u_char *
2837: sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2838: {
2839: if (lenp != NULL)
2840: *lenp = sshbuf_len(ssh->state->incoming_packet);
2841: return sshbuf_ptr(ssh->state->incoming_packet);
2842: }
2843:
2844: /* start a new packet */
2845:
2846: int
2847: sshpkt_start(struct ssh *ssh, u_char type)
2848: {
2849: u_char buf[9];
2850: int len;
2851:
2852: DBG(debug("packet_start[%d]", type));
2853: len = compat20 ? 6 : 9;
2854: memset(buf, 0, len - 1);
2855: buf[len - 1] = type;
2856: sshbuf_reset(ssh->state->outgoing_packet);
2857: return sshbuf_put(ssh->state->outgoing_packet, buf, len);
2858: }
2859:
2860: /* send it */
2861:
2862: int
2863: sshpkt_send(struct ssh *ssh)
2864: {
2865: if (compat20)
2866: return ssh_packet_send2(ssh);
2867: else
2868: return ssh_packet_send1(ssh);
2869: }
2870:
2871: int
2872: sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2873: {
2874: char buf[1024];
2875: va_list args;
2876: int r;
2877:
2878: va_start(args, fmt);
2879: vsnprintf(buf, sizeof(buf), fmt, args);
2880: va_end(args);
2881:
2882: if (compat20) {
2883: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2884: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2885: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2886: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2887: (r = sshpkt_send(ssh)) != 0)
2888: return r;
2889: } else {
2890: if ((r = sshpkt_start(ssh, SSH_MSG_DISCONNECT)) != 0 ||
2891: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2892: (r = sshpkt_send(ssh)) != 0)
2893: return r;
1.166 andreas 2894: }
1.201 markus 2895: return 0;
2896: }
2897:
2898: /* roundup current message to pad bytes */
2899: int
2900: sshpkt_add_padding(struct ssh *ssh, u_char pad)
2901: {
2902: ssh->state->extra_pad = pad;
2903: return 0;
1.1 deraadt 2904: }