Annotation of src/usr.bin/ssh/packet.c, Revision 1.223
1.223 ! dtucker 1: /* $OpenBSD: packet.c,v 1.222 2016/01/14 16:17:40 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"
1.197 djm 80: #include "ssherr.h"
1.201 markus 81: #include "sshbuf.h"
1.25 markus 82:
83: #ifdef PACKET_DEBUG
84: #define DBG(x) x
85: #else
86: #define DBG(x)
87: #endif
88:
1.159 markus 89: #define PACKET_MAX_SIZE (256 * 1024)
90:
1.161 andreas 91: struct packet_state {
92: u_int32_t seqnr;
93: u_int32_t packets;
94: u_int64_t blocks;
95: u_int64_t bytes;
96: };
97:
98: struct packet {
99: TAILQ_ENTRY(packet) next;
100: u_char type;
1.201 markus 101: struct sshbuf *payload;
1.161 andreas 102: };
103:
104: struct session_state {
105: /*
106: * This variable contains the file descriptors used for
107: * communicating with the other side. connection_in is used for
108: * reading; connection_out for writing. These can be the same
109: * descriptor, in which case it is assumed to be a socket.
110: */
111: int connection_in;
112: int connection_out;
113:
114: /* Protocol flags for the remote side. */
115: u_int remote_protocol_flags;
1.1 deraadt 116:
1.161 andreas 117: /* Encryption context for receiving data. Only used for decryption. */
1.201 markus 118: struct sshcipher_ctx receive_context;
1.1 deraadt 119:
1.161 andreas 120: /* Encryption context for sending data. Only used for encryption. */
1.201 markus 121: struct sshcipher_ctx send_context;
1.14 markus 122:
1.161 andreas 123: /* Buffer for raw input data from the socket. */
1.201 markus 124: struct sshbuf *input;
1.1 deraadt 125:
1.161 andreas 126: /* Buffer for raw output data going to the socket. */
1.201 markus 127: struct sshbuf *output;
1.1 deraadt 128:
1.161 andreas 129: /* Buffer for the partial outgoing packet being constructed. */
1.201 markus 130: struct sshbuf *outgoing_packet;
1.1 deraadt 131:
1.161 andreas 132: /* Buffer for the incoming packet currently being processed. */
1.201 markus 133: struct sshbuf *incoming_packet;
1.1 deraadt 134:
1.161 andreas 135: /* Scratch buffer for packet compression/decompression. */
1.201 markus 136: struct sshbuf *compression_buffer;
137:
138: /* Incoming/outgoing compression dictionaries */
139: z_stream compression_in_stream;
140: z_stream compression_out_stream;
141: int compression_in_started;
142: int compression_out_started;
143: int compression_in_failures;
144: int compression_out_failures;
1.1 deraadt 145:
1.161 andreas 146: /*
147: * Flag indicating whether packet compression/decompression is
148: * enabled.
149: */
150: int packet_compression;
1.1 deraadt 151:
1.161 andreas 152: /* default maximum packet size */
153: u_int max_packet_size;
1.1 deraadt 154:
1.161 andreas 155: /* Flag indicating whether this module has been initialized. */
156: int initialized;
1.12 markus 157:
1.161 andreas 158: /* Set to true if the connection is interactive. */
159: int interactive_mode;
1.1 deraadt 160:
1.161 andreas 161: /* Set to true if we are the server side. */
162: int server_side;
1.1 deraadt 163:
1.161 andreas 164: /* Set to true if we are authenticated. */
165: int after_authentication;
1.118 markus 166:
1.161 andreas 167: int keep_alive_timeouts;
1.118 markus 168:
1.161 andreas 169: /* The maximum time that we will wait to send or receive a packet */
170: int packet_timeout_ms;
1.151 dtucker 171:
1.161 andreas 172: /* Session key information for Encryption and MAC */
1.201 markus 173: struct newkeys *newkeys[MODE_MAX];
1.161 andreas 174: struct packet_state p_read, p_send;
1.154 dtucker 175:
1.184 dtucker 176: /* Volume-based rekeying */
1.161 andreas 177: u_int64_t max_blocks_in, max_blocks_out;
178: u_int32_t rekey_limit;
1.105 markus 179:
1.184 dtucker 180: /* Time-based rekeying */
1.208 markus 181: u_int32_t rekey_interval; /* how often in seconds */
1.184 dtucker 182: time_t rekey_time; /* time of last rekeying */
183:
1.161 andreas 184: /* Session key for protocol v1 */
185: u_char ssh1_key[SSH_SESSION_KEY_LENGTH];
186: u_int ssh1_keylen;
1.25 markus 187:
1.161 andreas 188: /* roundup current message to extra_pad bytes */
189: u_char extra_pad;
1.95 markus 190:
1.161 andreas 191: /* XXX discard incoming data after MAC error */
192: u_int packet_discard;
1.201 markus 193: struct sshmac *packet_discard_mac;
1.71 markus 194:
1.161 andreas 195: /* Used in packet_read_poll2() */
196: u_int packlen;
1.159 markus 197:
1.165 andreas 198: /* Used in packet_send2 */
199: int rekeying;
200:
201: /* Used in packet_set_interactive */
202: int set_interactive_called;
203:
204: /* Used in packet_set_maxsize */
205: int set_maxsize_called;
206:
1.201 markus 207: /* One-off warning about weak ciphers */
208: int cipher_warning_done;
209:
210: /* SSH1 CRC compensation attack detector */
211: struct deattack_ctx deattack;
212:
1.161 andreas 213: TAILQ_HEAD(, packet) outgoing;
1.105 markus 214: };
1.161 andreas 215:
1.201 markus 216: struct ssh *
217: ssh_alloc_session_state(void)
1.161 andreas 218: {
1.201 markus 219: struct ssh *ssh = NULL;
220: struct session_state *state = NULL;
1.161 andreas 221:
1.201 markus 222: if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
223: (state = calloc(1, sizeof(*state))) == NULL ||
224: (state->input = sshbuf_new()) == NULL ||
225: (state->output = sshbuf_new()) == NULL ||
226: (state->outgoing_packet = sshbuf_new()) == NULL ||
227: (state->incoming_packet = sshbuf_new()) == NULL)
228: goto fail;
229: TAILQ_INIT(&state->outgoing);
1.202 markus 230: TAILQ_INIT(&ssh->private_keys);
231: TAILQ_INIT(&ssh->public_keys);
1.201 markus 232: state->connection_in = -1;
233: state->connection_out = -1;
234: state->max_packet_size = 32768;
235: state->packet_timeout_ms = -1;
236: state->p_send.packets = state->p_read.packets = 0;
237: state->initialized = 1;
238: /*
239: * ssh_packet_send2() needs to queue packets until
240: * we've done the initial key exchange.
241: */
242: state->rekeying = 1;
243: ssh->state = state;
244: return ssh;
245: fail:
246: if (state) {
247: sshbuf_free(state->input);
248: sshbuf_free(state->output);
249: sshbuf_free(state->incoming_packet);
250: sshbuf_free(state->outgoing_packet);
251: free(state);
252: }
253: free(ssh);
254: return NULL;
1.161 andreas 255: }
1.105 markus 256:
1.16 markus 257: /*
258: * Sets the descriptors used for communication. Disables encryption until
259: * packet_set_encryption_key is called.
260: */
1.201 markus 261: struct ssh *
262: ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
1.1 deraadt 263: {
1.201 markus 264: struct session_state *state;
265: const struct sshcipher *none = cipher_by_name("none");
1.197 djm 266: int r;
1.97 deraadt 267:
1.205 djm 268: if (none == NULL) {
269: error("%s: cannot load cipher 'none'", __func__);
270: return NULL;
271: }
1.201 markus 272: if (ssh == NULL)
273: ssh = ssh_alloc_session_state();
1.205 djm 274: if (ssh == NULL) {
275: error("%s: cound not allocate state", __func__);
276: return NULL;
277: }
1.201 markus 278: state = ssh->state;
279: state->connection_in = fd_in;
280: state->connection_out = fd_out;
281: if ((r = cipher_init(&state->send_context, none,
1.197 djm 282: (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
1.201 markus 283: (r = cipher_init(&state->receive_context, none,
1.205 djm 284: (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
285: error("%s: cipher_init failed: %s", __func__, ssh_err(r));
1.209 jsg 286: free(ssh);
1.205 djm 287: return NULL;
288: }
1.201 markus 289: state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
290: deattack_init(&state->deattack);
1.207 djm 291: /*
292: * Cache the IP address of the remote connection for use in error
293: * messages that might be generated after the connection has closed.
294: */
295: (void)ssh_remote_ipaddr(ssh);
1.201 markus 296: return ssh;
1.1 deraadt 297: }
298:
1.154 dtucker 299: void
1.201 markus 300: ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
1.154 dtucker 301: {
1.201 markus 302: struct session_state *state = ssh->state;
303:
1.174 djm 304: if (timeout <= 0 || count <= 0) {
1.201 markus 305: state->packet_timeout_ms = -1;
1.154 dtucker 306: return;
307: }
308: if ((INT_MAX / 1000) / count < timeout)
1.201 markus 309: state->packet_timeout_ms = INT_MAX;
1.154 dtucker 310: else
1.201 markus 311: state->packet_timeout_ms = timeout * count * 1000;
1.154 dtucker 312: }
313:
1.201 markus 314: int
315: ssh_packet_stop_discard(struct ssh *ssh)
1.159 markus 316: {
1.201 markus 317: struct session_state *state = ssh->state;
318: int r;
319:
320: if (state->packet_discard_mac) {
1.159 markus 321: char buf[1024];
1.201 markus 322:
1.159 markus 323: memset(buf, 'a', sizeof(buf));
1.201 markus 324: while (sshbuf_len(state->incoming_packet) <
1.161 andreas 325: PACKET_MAX_SIZE)
1.201 markus 326: if ((r = sshbuf_put(state->incoming_packet, buf,
327: sizeof(buf))) != 0)
328: return r;
329: (void) mac_compute(state->packet_discard_mac,
330: state->p_read.seqnr,
331: sshbuf_ptr(state->incoming_packet), PACKET_MAX_SIZE,
332: NULL, 0);
1.159 markus 333: }
1.220 djm 334: logit("Finished discarding for %.200s port %d",
335: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.201 markus 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: {
1.220 djm 447: const int sock = ssh->state->connection_in;
448:
1.201 markus 449: /* Check whether we have cached the ipaddr. */
1.220 djm 450: if (ssh->remote_ipaddr == NULL) {
451: if (ssh_packet_connection_is_on_socket(ssh)) {
452: ssh->remote_ipaddr = get_peer_ipaddr(sock);
453: ssh->remote_port = get_sock_port(sock, 0);
454: } else {
455: ssh->remote_ipaddr = strdup("UNKNOWN");
456: ssh->remote_port = 0;
457: }
458: }
1.201 markus 459: return ssh->remote_ipaddr;
1.1 deraadt 460: }
461:
1.220 djm 462: /* Returns the port number of the remote host. */
463:
464: int
465: ssh_remote_port(struct ssh *ssh)
466: {
467: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
468: return ssh->remote_port;
469: }
470:
1.1 deraadt 471: /* Closes the connection and clears and frees internal data structures. */
472:
1.2 provos 473: void
1.201 markus 474: ssh_packet_close(struct ssh *ssh)
1.1 deraadt 475: {
1.201 markus 476: struct session_state *state = ssh->state;
477: int r;
478: u_int mode;
479:
480: if (!state->initialized)
1.14 markus 481: return;
1.201 markus 482: state->initialized = 0;
483: if (state->connection_in == state->connection_out) {
484: shutdown(state->connection_out, SHUT_RDWR);
485: close(state->connection_out);
1.14 markus 486: } else {
1.201 markus 487: close(state->connection_in);
488: close(state->connection_out);
1.14 markus 489: }
1.201 markus 490: sshbuf_free(state->input);
491: sshbuf_free(state->output);
492: sshbuf_free(state->outgoing_packet);
493: sshbuf_free(state->incoming_packet);
494: for (mode = 0; mode < MODE_MAX; mode++)
495: kex_free_newkeys(state->newkeys[mode]);
496: if (state->compression_buffer) {
497: sshbuf_free(state->compression_buffer);
498: if (state->compression_out_started) {
499: z_streamp stream = &state->compression_out_stream;
500: debug("compress outgoing: "
501: "raw data %llu, compressed %llu, factor %.2f",
502: (unsigned long long)stream->total_in,
503: (unsigned long long)stream->total_out,
504: stream->total_in == 0 ? 0.0 :
505: (double) stream->total_out / stream->total_in);
506: if (state->compression_out_failures == 0)
507: deflateEnd(stream);
508: }
509: if (state->compression_in_started) {
510: z_streamp stream = &state->compression_out_stream;
511: debug("compress incoming: "
512: "raw data %llu, compressed %llu, factor %.2f",
513: (unsigned long long)stream->total_out,
514: (unsigned long long)stream->total_in,
515: stream->total_out == 0 ? 0.0 :
516: (double) stream->total_in / stream->total_out);
517: if (state->compression_in_failures == 0)
518: inflateEnd(stream);
519: }
1.14 markus 520: }
1.201 markus 521: if ((r = cipher_cleanup(&state->send_context)) != 0)
522: error("%s: cipher_cleanup failed: %s", __func__, ssh_err(r));
523: if ((r = cipher_cleanup(&state->receive_context)) != 0)
524: error("%s: cipher_cleanup failed: %s", __func__, ssh_err(r));
1.219 mmcc 525: free(ssh->remote_ipaddr);
526: ssh->remote_ipaddr = NULL;
1.201 markus 527: free(ssh->state);
528: ssh->state = NULL;
1.1 deraadt 529: }
530:
531: /* Sets remote side protocol flags. */
532:
1.2 provos 533: void
1.201 markus 534: ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
1.1 deraadt 535: {
1.201 markus 536: ssh->state->remote_protocol_flags = protocol_flags;
1.1 deraadt 537: }
538:
539: /* Returns the remote protocol flags set earlier by the above function. */
540:
1.40 markus 541: u_int
1.201 markus 542: ssh_packet_get_protocol_flags(struct ssh *ssh)
1.1 deraadt 543: {
1.201 markus 544: return ssh->state->remote_protocol_flags;
1.1 deraadt 545: }
546:
1.16 markus 547: /*
548: * Starts packet compression from the next packet on in both directions.
549: * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
550: */
1.1 deraadt 551:
1.201 markus 552: static int
553: ssh_packet_init_compression(struct ssh *ssh)
1.60 markus 554: {
1.201 markus 555: if (!ssh->state->compression_buffer &&
556: ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
557: return SSH_ERR_ALLOC_FAIL;
558: return 0;
1.60 markus 559: }
560:
1.201 markus 561: static int
562: start_compression_out(struct ssh *ssh, int level)
1.1 deraadt 563: {
1.201 markus 564: if (level < 1 || level > 9)
565: return SSH_ERR_INVALID_ARGUMENT;
566: debug("Enabling compression at level %d.", level);
567: if (ssh->state->compression_out_started == 1)
568: deflateEnd(&ssh->state->compression_out_stream);
569: switch (deflateInit(&ssh->state->compression_out_stream, level)) {
570: case Z_OK:
571: ssh->state->compression_out_started = 1;
572: break;
573: case Z_MEM_ERROR:
574: return SSH_ERR_ALLOC_FAIL;
575: default:
576: return SSH_ERR_INTERNAL_ERROR;
577: }
578: return 0;
1.1 deraadt 579: }
580:
1.201 markus 581: static int
582: start_compression_in(struct ssh *ssh)
583: {
584: if (ssh->state->compression_in_started == 1)
585: inflateEnd(&ssh->state->compression_in_stream);
586: switch (inflateInit(&ssh->state->compression_in_stream)) {
587: case Z_OK:
588: ssh->state->compression_in_started = 1;
589: break;
590: case Z_MEM_ERROR:
591: return SSH_ERR_ALLOC_FAIL;
592: default:
593: return SSH_ERR_INTERNAL_ERROR;
594: }
595: return 0;
596: }
1.95 markus 597:
1.201 markus 598: int
599: ssh_packet_start_compression(struct ssh *ssh, int level)
1.1 deraadt 600: {
1.197 djm 601: int r;
1.97 deraadt 602:
1.201 markus 603: if (ssh->state->packet_compression && !compat20)
604: return SSH_ERR_INTERNAL_ERROR;
605: ssh->state->packet_compression = 1;
606: if ((r = ssh_packet_init_compression(ssh)) != 0 ||
607: (r = start_compression_in(ssh)) != 0 ||
608: (r = start_compression_out(ssh, level)) != 0)
609: return r;
610: return 0;
1.95 markus 611: }
612:
1.201 markus 613: /* XXX remove need for separate compression buffer */
614: static int
615: compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.95 markus 616: {
1.201 markus 617: u_char buf[4096];
618: int r, status;
619:
620: if (ssh->state->compression_out_started != 1)
621: return SSH_ERR_INTERNAL_ERROR;
622:
623: /* This case is not handled below. */
624: if (sshbuf_len(in) == 0)
625: return 0;
626:
627: /* Input is the contents of the input buffer. */
628: if ((ssh->state->compression_out_stream.next_in =
629: sshbuf_mutable_ptr(in)) == NULL)
630: return SSH_ERR_INTERNAL_ERROR;
631: ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
632:
633: /* Loop compressing until deflate() returns with avail_out != 0. */
634: do {
635: /* Set up fixed-size output buffer. */
636: ssh->state->compression_out_stream.next_out = buf;
637: ssh->state->compression_out_stream.avail_out = sizeof(buf);
638:
639: /* Compress as much data into the buffer as possible. */
640: status = deflate(&ssh->state->compression_out_stream,
641: Z_PARTIAL_FLUSH);
642: switch (status) {
643: case Z_MEM_ERROR:
644: return SSH_ERR_ALLOC_FAIL;
645: case Z_OK:
646: /* Append compressed data to output_buffer. */
647: if ((r = sshbuf_put(out, buf, sizeof(buf) -
648: ssh->state->compression_out_stream.avail_out)) != 0)
649: return r;
650: break;
651: case Z_STREAM_ERROR:
652: default:
653: ssh->state->compression_out_failures++;
654: return SSH_ERR_INVALID_FORMAT;
655: }
656: } while (ssh->state->compression_out_stream.avail_out == 0);
657: return 0;
1.1 deraadt 658: }
659:
1.201 markus 660: static int
661: uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.1 deraadt 662: {
1.201 markus 663: u_char buf[4096];
664: int r, status;
1.1 deraadt 665:
1.201 markus 666: if (ssh->state->compression_in_started != 1)
667: return SSH_ERR_INTERNAL_ERROR;
1.25 markus 668:
1.201 markus 669: if ((ssh->state->compression_in_stream.next_in =
670: sshbuf_mutable_ptr(in)) == NULL)
671: return SSH_ERR_INTERNAL_ERROR;
672: ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
1.97 deraadt 673:
1.201 markus 674: for (;;) {
675: /* Set up fixed-size output buffer. */
676: ssh->state->compression_in_stream.next_out = buf;
677: ssh->state->compression_in_stream.avail_out = sizeof(buf);
678:
679: status = inflate(&ssh->state->compression_in_stream,
680: Z_PARTIAL_FLUSH);
681: switch (status) {
682: case Z_OK:
683: if ((r = sshbuf_put(out, buf, sizeof(buf) -
684: ssh->state->compression_in_stream.avail_out)) != 0)
685: return r;
686: break;
687: case Z_BUF_ERROR:
688: /*
689: * Comments in zlib.h say that we should keep calling
690: * inflate() until we get an error. This appears to
691: * be the error that we get.
692: */
693: return 0;
694: case Z_DATA_ERROR:
695: return SSH_ERR_INVALID_FORMAT;
696: case Z_MEM_ERROR:
697: return SSH_ERR_ALLOC_FAIL;
698: case Z_STREAM_ERROR:
699: default:
700: ssh->state->compression_in_failures++;
701: return SSH_ERR_INTERNAL_ERROR;
702: }
703: }
704: /* NOTREACHED */
1.1 deraadt 705: }
1.125 deraadt 706:
1.201 markus 707: /* Serialise compression state into a blob for privsep */
708: static int
709: ssh_packet_get_compress_state(struct sshbuf *m, struct ssh *ssh)
1.1 deraadt 710: {
1.201 markus 711: struct session_state *state = ssh->state;
712: struct sshbuf *b;
713: int r;
714:
715: if ((b = sshbuf_new()) == NULL)
716: return SSH_ERR_ALLOC_FAIL;
717: if (state->compression_in_started) {
718: if ((r = sshbuf_put_string(b, &state->compression_in_stream,
719: sizeof(state->compression_in_stream))) != 0)
720: goto out;
721: } else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
722: goto out;
723: if (state->compression_out_started) {
724: if ((r = sshbuf_put_string(b, &state->compression_out_stream,
725: sizeof(state->compression_out_stream))) != 0)
726: goto out;
727: } else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
728: goto out;
729: r = sshbuf_put_stringb(m, b);
730: out:
731: sshbuf_free(b);
732: return r;
1.1 deraadt 733: }
1.125 deraadt 734:
1.201 markus 735: /* Deserialise compression state from a blob for privsep */
736: static int
737: ssh_packet_set_compress_state(struct ssh *ssh, struct sshbuf *m)
1.162 andreas 738: {
1.201 markus 739: struct session_state *state = ssh->state;
740: struct sshbuf *b = NULL;
741: int r;
742: const u_char *inblob, *outblob;
743: size_t inl, outl;
1.162 andreas 744:
1.201 markus 745: if ((r = sshbuf_froms(m, &b)) != 0)
746: goto out;
747: if ((r = sshbuf_get_string_direct(b, &inblob, &inl)) != 0 ||
748: (r = sshbuf_get_string_direct(b, &outblob, &outl)) != 0)
749: goto out;
750: if (inl == 0)
751: state->compression_in_started = 0;
752: else if (inl != sizeof(state->compression_in_stream)) {
753: r = SSH_ERR_INTERNAL_ERROR;
754: goto out;
755: } else {
756: state->compression_in_started = 1;
757: memcpy(&state->compression_in_stream, inblob, inl);
758: }
759: if (outl == 0)
760: state->compression_out_started = 0;
761: else if (outl != sizeof(state->compression_out_stream)) {
762: r = SSH_ERR_INTERNAL_ERROR;
763: goto out;
764: } else {
765: state->compression_out_started = 1;
766: memcpy(&state->compression_out_stream, outblob, outl);
767: }
768: r = 0;
769: out:
770: sshbuf_free(b);
771: return r;
1.1 deraadt 772: }
1.125 deraadt 773:
1.24 markus 774: void
1.201 markus 775: ssh_packet_set_compress_hooks(struct ssh *ssh, void *ctx,
776: void *(*allocfunc)(void *, u_int, u_int),
777: void (*freefunc)(void *, void *))
778: {
779: ssh->state->compression_out_stream.zalloc = (alloc_func)allocfunc;
780: ssh->state->compression_out_stream.zfree = (free_func)freefunc;
781: ssh->state->compression_out_stream.opaque = ctx;
782: ssh->state->compression_in_stream.zalloc = (alloc_func)allocfunc;
783: ssh->state->compression_in_stream.zfree = (free_func)freefunc;
784: ssh->state->compression_in_stream.opaque = ctx;
1.24 markus 785: }
1.125 deraadt 786:
1.201 markus 787: /*
788: * Causes any further packets to be encrypted using the given key. The same
789: * key is used for both sending and reception. However, both directions are
790: * encrypted independently of each other.
791: */
1.125 deraadt 792:
1.2 provos 793: void
1.201 markus 794: ssh_packet_set_encryption_key(struct ssh *ssh, const u_char *key, u_int keylen, int number)
1.1 deraadt 795: {
1.211 djm 796: #ifndef WITH_SSH1
797: fatal("no SSH protocol 1 support");
798: #else /* WITH_SSH1 */
1.201 markus 799: struct session_state *state = ssh->state;
800: const struct sshcipher *cipher = cipher_by_number(number);
801: int r;
802: const char *wmsg;
1.125 deraadt 803:
1.201 markus 804: if (cipher == NULL)
805: fatal("%s: unknown cipher number %d", __func__, number);
806: if (keylen < 20)
807: fatal("%s: keylen too small: %d", __func__, keylen);
808: if (keylen > SSH_SESSION_KEY_LENGTH)
809: fatal("%s: keylen too big: %d", __func__, keylen);
810: memcpy(state->ssh1_key, key, keylen);
811: state->ssh1_keylen = keylen;
812: if ((r = cipher_init(&state->send_context, cipher, key, keylen,
813: NULL, 0, CIPHER_ENCRYPT)) != 0 ||
814: (r = cipher_init(&state->receive_context, cipher, key, keylen,
815: NULL, 0, CIPHER_DECRYPT) != 0))
816: fatal("%s: cipher_init failed: %s", __func__, ssh_err(r));
817: if (!state->cipher_warning_done &&
818: ((wmsg = cipher_warning_message(&state->send_context)) != NULL ||
819: (wmsg = cipher_warning_message(&state->send_context)) != NULL)) {
820: error("Warning: %s", wmsg);
821: state->cipher_warning_done = 1;
822: }
1.211 djm 823: #endif /* WITH_SSH1 */
1.170 djm 824: }
825:
1.16 markus 826: /*
827: * Finalizes and sends the packet. If the encryption key has been set,
828: * encrypts the packet before sending.
829: */
1.14 markus 830:
1.201 markus 831: int
832: ssh_packet_send1(struct ssh *ssh)
1.1 deraadt 833: {
1.201 markus 834: struct session_state *state = ssh->state;
1.89 markus 835: u_char buf[8], *cp;
1.201 markus 836: int r, padding, len;
1.40 markus 837: u_int checksum;
1.14 markus 838:
1.16 markus 839: /*
840: * If using packet compression, compress the payload of the outgoing
841: * packet.
842: */
1.201 markus 843: if (state->packet_compression) {
844: sshbuf_reset(state->compression_buffer);
1.14 markus 845: /* Skip padding. */
1.201 markus 846: if ((r = sshbuf_consume(state->outgoing_packet, 8)) != 0)
847: goto out;
1.14 markus 848: /* padding */
1.201 markus 849: if ((r = sshbuf_put(state->compression_buffer,
850: "\0\0\0\0\0\0\0\0", 8)) != 0)
851: goto out;
852: if ((r = compress_buffer(ssh, state->outgoing_packet,
853: state->compression_buffer)) != 0)
854: goto out;
855: sshbuf_reset(state->outgoing_packet);
856: if ((r = sshbuf_putb(state->outgoing_packet,
857: state->compression_buffer)) != 0)
858: goto out;
1.14 markus 859: }
860: /* Compute packet length without padding (add checksum, remove padding). */
1.201 markus 861: len = sshbuf_len(state->outgoing_packet) + 4 - 8;
1.14 markus 862:
1.32 markus 863: /* Insert padding. Initialized to zero in packet_start1() */
1.14 markus 864: padding = 8 - len % 8;
1.201 markus 865: if (!state->send_context.plaintext) {
866: cp = sshbuf_mutable_ptr(state->outgoing_packet);
867: if (cp == NULL) {
868: r = SSH_ERR_INTERNAL_ERROR;
869: goto out;
1.14 markus 870: }
1.201 markus 871: arc4random_buf(cp + 8 - padding, padding);
1.14 markus 872: }
1.201 markus 873: if ((r = sshbuf_consume(state->outgoing_packet, 8 - padding)) != 0)
874: goto out;
1.14 markus 875:
876: /* Add check bytes. */
1.201 markus 877: checksum = ssh_crc32(sshbuf_ptr(state->outgoing_packet),
878: sshbuf_len(state->outgoing_packet));
879: POKE_U32(buf, checksum);
880: if ((r = sshbuf_put(state->outgoing_packet, buf, 4)) != 0)
881: goto out;
1.1 deraadt 882:
883: #ifdef PACKET_DEBUG
1.14 markus 884: fprintf(stderr, "packet_send plain: ");
1.201 markus 885: sshbuf_dump(state->outgoing_packet, stderr);
1.1 deraadt 886: #endif
887:
1.14 markus 888: /* Append to output. */
1.201 markus 889: POKE_U32(buf, len);
890: if ((r = sshbuf_put(state->output, buf, 4)) != 0)
891: goto out;
892: if ((r = sshbuf_reserve(state->output,
893: sshbuf_len(state->outgoing_packet), &cp)) != 0)
894: goto out;
895: if ((r = cipher_crypt(&state->send_context, 0, cp,
896: sshbuf_ptr(state->outgoing_packet),
897: sshbuf_len(state->outgoing_packet), 0, 0)) != 0)
898: goto out;
1.14 markus 899:
1.1 deraadt 900: #ifdef PACKET_DEBUG
1.14 markus 901: fprintf(stderr, "encrypted: ");
1.201 markus 902: sshbuf_dump(state->output, stderr);
1.1 deraadt 903: #endif
1.201 markus 904: state->p_send.packets++;
905: state->p_send.bytes += len +
906: sshbuf_len(state->outgoing_packet);
907: sshbuf_reset(state->outgoing_packet);
1.1 deraadt 908:
1.16 markus 909: /*
1.120 djm 910: * Note that the packet is now only buffered in output. It won't be
1.205 djm 911: * actually sent until ssh_packet_write_wait or ssh_packet_write_poll
912: * is called.
1.16 markus 913: */
1.201 markus 914: r = 0;
915: out:
916: return r;
1.1 deraadt 917: }
918:
1.201 markus 919: int
920: ssh_set_newkeys(struct ssh *ssh, int mode)
1.57 markus 921: {
1.201 markus 922: struct session_state *state = ssh->state;
923: struct sshenc *enc;
924: struct sshmac *mac;
925: struct sshcomp *comp;
926: struct sshcipher_ctx *cc;
1.105 markus 927: u_int64_t *max_blocks;
1.201 markus 928: const char *wmsg;
1.197 djm 929: int r, crypt_type;
1.57 markus 930:
1.100 markus 931: debug2("set_newkeys: mode %d", mode);
1.57 markus 932:
1.88 markus 933: if (mode == MODE_OUT) {
1.201 markus 934: cc = &state->send_context;
1.115 avsm 935: crypt_type = CIPHER_ENCRYPT;
1.201 markus 936: state->p_send.packets = state->p_send.blocks = 0;
937: max_blocks = &state->max_blocks_out;
1.88 markus 938: } else {
1.201 markus 939: cc = &state->receive_context;
1.115 avsm 940: crypt_type = CIPHER_DECRYPT;
1.201 markus 941: state->p_read.packets = state->p_read.blocks = 0;
942: max_blocks = &state->max_blocks_in;
1.88 markus 943: }
1.201 markus 944: if (state->newkeys[mode] != NULL) {
1.100 markus 945: debug("set_newkeys: rekeying");
1.201 markus 946: if ((r = cipher_cleanup(cc)) != 0)
947: return r;
948: enc = &state->newkeys[mode]->enc;
949: mac = &state->newkeys[mode]->mac;
950: comp = &state->newkeys[mode]->comp;
1.148 pvalchev 951: mac_clear(mac);
1.192 djm 952: explicit_bzero(enc->iv, enc->iv_len);
953: explicit_bzero(enc->key, enc->key_len);
954: explicit_bzero(mac->key, mac->key_len);
1.186 djm 955: free(enc->name);
956: free(enc->iv);
957: free(enc->key);
958: free(mac->name);
959: free(mac->key);
960: free(comp->name);
1.201 markus 961: free(state->newkeys[mode]);
1.57 markus 962: }
1.201 markus 963: /* move newkeys from kex to state */
964: if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
965: return SSH_ERR_INTERNAL_ERROR;
966: ssh->kex->newkeys[mode] = NULL;
967: enc = &state->newkeys[mode]->enc;
968: mac = &state->newkeys[mode]->mac;
969: comp = &state->newkeys[mode]->comp;
970: if (cipher_authlen(enc->cipher) == 0) {
971: if ((r = mac_init(mac)) != 0)
972: return r;
973: }
974: mac->enabled = 1;
1.57 markus 975: DBG(debug("cipher_init_context: %d", mode));
1.197 djm 976: if ((r = cipher_init(cc, enc->cipher, enc->key, enc->key_len,
977: enc->iv, enc->iv_len, crypt_type)) != 0)
1.201 markus 978: return r;
979: if (!state->cipher_warning_done &&
980: (wmsg = cipher_warning_message(cc)) != NULL) {
981: error("Warning: %s", wmsg);
982: state->cipher_warning_done = 1;
983: }
1.91 markus 984: /* Deleting the keys does not gain extra security */
1.192 djm 985: /* explicit_bzero(enc->iv, enc->block_size);
986: explicit_bzero(enc->key, enc->key_len);
987: explicit_bzero(mac->key, mac->key_len); */
1.118 markus 988: if ((comp->type == COMP_ZLIB ||
1.161 andreas 989: (comp->type == COMP_DELAYED &&
1.201 markus 990: state->after_authentication)) && comp->enabled == 0) {
991: if ((r = ssh_packet_init_compression(ssh)) < 0)
992: return r;
993: if (mode == MODE_OUT) {
994: if ((r = start_compression_out(ssh, 6)) != 0)
995: return r;
996: } else {
997: if ((r = start_compression_in(ssh)) != 0)
998: return r;
999: }
1.57 markus 1000: comp->enabled = 1;
1001: }
1.109 markus 1002: /*
1003: * The 2^(blocksize*2) limit is too expensive for 3DES,
1004: * blowfish, etc, so enforce a 1GB limit for small blocksizes.
1005: */
1006: if (enc->block_size >= 16)
1007: *max_blocks = (u_int64_t)1 << (enc->block_size*2);
1008: else
1009: *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1.201 markus 1010: if (state->rekey_limit)
1.161 andreas 1011: *max_blocks = MIN(*max_blocks,
1.201 markus 1012: state->rekey_limit / enc->block_size);
1013: return 0;
1.57 markus 1014: }
1015:
1.16 markus 1016: /*
1.118 markus 1017: * Delayed compression for SSH2 is enabled after authentication:
1.143 dtucker 1018: * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1.118 markus 1019: * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
1020: */
1.201 markus 1021: static int
1022: ssh_packet_enable_delayed_compress(struct ssh *ssh)
1.118 markus 1023: {
1.201 markus 1024: struct session_state *state = ssh->state;
1025: struct sshcomp *comp = NULL;
1026: int r, mode;
1.118 markus 1027:
1028: /*
1029: * Remember that we are past the authentication step, so rekeying
1030: * with COMP_DELAYED will turn on compression immediately.
1031: */
1.201 markus 1032: state->after_authentication = 1;
1.118 markus 1033: for (mode = 0; mode < MODE_MAX; mode++) {
1.145 markus 1034: /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1.201 markus 1035: if (state->newkeys[mode] == NULL)
1.145 markus 1036: continue;
1.201 markus 1037: comp = &state->newkeys[mode]->comp;
1.118 markus 1038: if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1.201 markus 1039: if ((r = ssh_packet_init_compression(ssh)) != 0)
1040: return r;
1041: if (mode == MODE_OUT) {
1042: if ((r = start_compression_out(ssh, 6)) != 0)
1043: return r;
1044: } else {
1045: if ((r = start_compression_in(ssh)) != 0)
1046: return r;
1047: }
1.118 markus 1048: comp->enabled = 1;
1049: }
1050: }
1.201 markus 1051: return 0;
1.118 markus 1052: }
1053:
1054: /*
1.25 markus 1055: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1056: */
1.201 markus 1057: int
1058: ssh_packet_send2_wrapped(struct ssh *ssh)
1.25 markus 1059: {
1.201 markus 1060: struct session_state *state = ssh->state;
1.200 markus 1061: u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1.178 markus 1062: u_char padlen, pad = 0;
1.201 markus 1063: u_int authlen = 0, aadlen = 0;
1064: u_int len;
1065: struct sshenc *enc = NULL;
1066: struct sshmac *mac = NULL;
1067: struct sshcomp *comp = NULL;
1068: int r, block_size;
1069:
1070: if (state->newkeys[MODE_OUT] != NULL) {
1071: enc = &state->newkeys[MODE_OUT]->enc;
1072: mac = &state->newkeys[MODE_OUT]->mac;
1073: comp = &state->newkeys[MODE_OUT]->comp;
1.180 markus 1074: /* disable mac for authenticated encryption */
1075: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1076: mac = NULL;
1.25 markus 1077: }
1.88 markus 1078: block_size = enc ? enc->block_size : 8;
1.180 markus 1079: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1080:
1.201 markus 1081: type = (sshbuf_ptr(state->outgoing_packet))[5];
1.25 markus 1082:
1083: #ifdef PACKET_DEBUG
1084: fprintf(stderr, "plain: ");
1.201 markus 1085: sshbuf_dump(state->outgoing_packet, stderr);
1.25 markus 1086: #endif
1087:
1088: if (comp && comp->enabled) {
1.201 markus 1089: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1090: /* skip header, compress only payload */
1.201 markus 1091: if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1092: goto out;
1093: sshbuf_reset(state->compression_buffer);
1094: if ((r = compress_buffer(ssh, state->outgoing_packet,
1095: state->compression_buffer)) != 0)
1096: goto out;
1097: sshbuf_reset(state->outgoing_packet);
1098: if ((r = sshbuf_put(state->outgoing_packet,
1099: "\0\0\0\0\0", 5)) != 0 ||
1100: (r = sshbuf_putb(state->outgoing_packet,
1101: state->compression_buffer)) != 0)
1102: goto out;
1103: DBG(debug("compression: raw %d compressed %zd", len,
1104: sshbuf_len(state->outgoing_packet)));
1.25 markus 1105: }
1106:
1107: /* sizeof (packet_len + pad_len + payload) */
1.201 markus 1108: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1109:
1110: /*
1111: * calc size of padding, alloc space, get random data,
1112: * minimum padding is 4 bytes
1113: */
1.178 markus 1114: len -= aadlen; /* packet length is not encrypted for EtM modes */
1.25 markus 1115: padlen = block_size - (len % block_size);
1116: if (padlen < 4)
1117: padlen += block_size;
1.201 markus 1118: if (state->extra_pad) {
1.71 markus 1119: /* will wrap if extra_pad+padlen > 255 */
1.201 markus 1120: state->extra_pad =
1121: roundup(state->extra_pad, block_size);
1122: pad = state->extra_pad -
1123: ((len + padlen) % state->extra_pad);
1.193 djm 1124: DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1.201 markus 1125: __func__, pad, len, padlen, state->extra_pad));
1.71 markus 1126: padlen += pad;
1.201 markus 1127: state->extra_pad = 0;
1.71 markus 1128: }
1.201 markus 1129: if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1130: goto out;
1131: if (enc && !state->send_context.plaintext) {
1.32 markus 1132: /* random padding */
1.201 markus 1133: arc4random_buf(cp, padlen);
1.32 markus 1134: } else {
1135: /* clear padding */
1.192 djm 1136: explicit_bzero(cp, padlen);
1.25 markus 1137: }
1.178 markus 1138: /* sizeof (packet_len + pad_len + payload + padding) */
1.201 markus 1139: len = sshbuf_len(state->outgoing_packet);
1140: cp = sshbuf_mutable_ptr(state->outgoing_packet);
1141: if (cp == NULL) {
1142: r = SSH_ERR_INTERNAL_ERROR;
1143: goto out;
1144: }
1.25 markus 1145: /* packet_length includes payload, padding and padding length field */
1.201 markus 1146: POKE_U32(cp, len - 4);
1.89 markus 1147: cp[4] = padlen;
1.178 markus 1148: DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1149: len, padlen, aadlen));
1.25 markus 1150:
1151: /* compute MAC over seqnr and packet(length fields, payload, padding) */
1.178 markus 1152: if (mac && mac->enabled && !mac->etm) {
1.201 markus 1153: if ((r = mac_compute(mac, state->p_send.seqnr,
1154: sshbuf_ptr(state->outgoing_packet), len,
1.200 markus 1155: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1156: goto out;
1157: DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1.25 markus 1158: }
1159: /* encrypt packet and append to output buffer. */
1.201 markus 1160: if ((r = sshbuf_reserve(state->output,
1161: sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1162: goto out;
1163: if ((r = cipher_crypt(&state->send_context, state->p_send.seqnr, cp,
1164: sshbuf_ptr(state->outgoing_packet),
1165: len - aadlen, aadlen, authlen)) != 0)
1166: goto out;
1.25 markus 1167: /* append unencrypted MAC */
1.178 markus 1168: if (mac && mac->enabled) {
1169: if (mac->etm) {
1170: /* EtM: compute mac over aadlen + cipher text */
1.201 markus 1171: if ((r = mac_compute(mac, state->p_send.seqnr,
1172: cp, len, macbuf, sizeof(macbuf))) != 0)
1173: goto out;
1.178 markus 1174: DBG(debug("done calc MAC(EtM) out #%d",
1.201 markus 1175: state->p_send.seqnr));
1.178 markus 1176: }
1.201 markus 1177: if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1178: goto out;
1.178 markus 1179: }
1.25 markus 1180: #ifdef PACKET_DEBUG
1181: fprintf(stderr, "encrypted: ");
1.201 markus 1182: sshbuf_dump(state->output, stderr);
1.25 markus 1183: #endif
1.29 markus 1184: /* increment sequence number for outgoing packets */
1.201 markus 1185: if (++state->p_send.seqnr == 0)
1.106 itojun 1186: logit("outgoing seqnr wraps around");
1.201 markus 1187: if (++state->p_send.packets == 0)
1188: if (!(ssh->compat & SSH_BUG_NOREKEY))
1189: return SSH_ERR_NEED_REKEY;
1190: state->p_send.blocks += len / block_size;
1191: state->p_send.bytes += len;
1192: sshbuf_reset(state->outgoing_packet);
1.25 markus 1193:
1.57 markus 1194: if (type == SSH2_MSG_NEWKEYS)
1.201 markus 1195: r = ssh_set_newkeys(ssh, MODE_OUT);
1196: else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1197: r = ssh_packet_enable_delayed_compress(ssh);
1198: else
1199: r = 0;
1200: out:
1201: return r;
1.25 markus 1202: }
1203:
1.201 markus 1204: int
1205: ssh_packet_send2(struct ssh *ssh)
1.105 markus 1206: {
1.201 markus 1207: struct session_state *state = ssh->state;
1.105 markus 1208: struct packet *p;
1.201 markus 1209: u_char type;
1210: int r;
1.105 markus 1211:
1.201 markus 1212: type = sshbuf_ptr(state->outgoing_packet)[5];
1.105 markus 1213:
1214: /* during rekeying we can only send key exchange messages */
1.201 markus 1215: if (state->rekeying) {
1.175 markus 1216: if ((type < SSH2_MSG_TRANSPORT_MIN) ||
1217: (type > SSH2_MSG_TRANSPORT_MAX) ||
1218: (type == SSH2_MSG_SERVICE_REQUEST) ||
1.218 markus 1219: (type == SSH2_MSG_SERVICE_ACCEPT) ||
1220: (type == SSH2_MSG_EXT_INFO)) {
1.105 markus 1221: debug("enqueue packet: %u", type);
1.201 markus 1222: p = calloc(1, sizeof(*p));
1223: if (p == NULL)
1224: return SSH_ERR_ALLOC_FAIL;
1.105 markus 1225: p->type = type;
1.201 markus 1226: p->payload = state->outgoing_packet;
1227: TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1228: state->outgoing_packet = sshbuf_new();
1229: if (state->outgoing_packet == NULL)
1230: return SSH_ERR_ALLOC_FAIL;
1231: return 0;
1.105 markus 1232: }
1233: }
1234:
1235: /* rekeying starts with sending KEXINIT */
1236: if (type == SSH2_MSG_KEXINIT)
1.201 markus 1237: state->rekeying = 1;
1.105 markus 1238:
1.201 markus 1239: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1240: return r;
1.105 markus 1241:
1242: /* after a NEWKEYS message we can send the complete queue */
1243: if (type == SSH2_MSG_NEWKEYS) {
1.201 markus 1244: state->rekeying = 0;
1245: state->rekey_time = monotime();
1246: while ((p = TAILQ_FIRST(&state->outgoing))) {
1.105 markus 1247: type = p->type;
1248: debug("dequeue packet: %u", type);
1.201 markus 1249: sshbuf_free(state->outgoing_packet);
1250: state->outgoing_packet = p->payload;
1251: TAILQ_REMOVE(&state->outgoing, p, next);
1.186 djm 1252: free(p);
1.201 markus 1253: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1254: return r;
1.105 markus 1255: }
1256: }
1.201 markus 1257: return 0;
1.25 markus 1258: }
1259:
1260: /*
1.16 markus 1261: * Waits until a packet has been received, and returns its type. Note that
1262: * no other data is processed until this returns, so this function should not
1263: * be used during the interactive session.
1264: */
1.1 deraadt 1265:
1.2 provos 1266: int
1.201 markus 1267: ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.1 deraadt 1268: {
1.201 markus 1269: struct session_state *state = ssh->state;
1.222 markus 1270: int len, r, ms_remain;
1.56 millert 1271: fd_set *setp;
1.14 markus 1272: char buf[8192];
1.155 deraadt 1273: struct timeval timeout, start, *timeoutp = NULL;
1274:
1.25 markus 1275: DBG(debug("packet_read()"));
1.14 markus 1276:
1.214 deraadt 1277: setp = calloc(howmany(state->connection_in + 1,
1.161 andreas 1278: NFDBITS), sizeof(fd_mask));
1.201 markus 1279: if (setp == NULL)
1280: return SSH_ERR_ALLOC_FAIL;
1.56 millert 1281:
1.205 djm 1282: /*
1283: * Since we are blocking, ensure that all written packets have
1284: * been sent.
1285: */
1.210 markus 1286: if ((r = ssh_packet_write_wait(ssh)) != 0)
1287: goto out;
1.14 markus 1288:
1289: /* Stay in the loop until we have received a complete packet. */
1290: for (;;) {
1291: /* Try to read a packet from the buffer. */
1.201 markus 1292: r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1293: if (r != 0)
1294: break;
1.62 markus 1295: if (!compat20 && (
1.201 markus 1296: *typep == SSH_SMSG_SUCCESS
1297: || *typep == SSH_SMSG_FAILURE
1298: || *typep == SSH_CMSG_EOF
1299: || *typep == SSH_CMSG_EXIT_CONFIRMATION))
1300: if ((r = sshpkt_get_end(ssh)) != 0)
1301: break;
1.14 markus 1302: /* If we got a packet, return it. */
1.201 markus 1303: if (*typep != SSH_MSG_NONE)
1304: break;
1.16 markus 1305: /*
1306: * Otherwise, wait for some data to arrive, add it to the
1307: * buffer, and try again.
1308: */
1.201 markus 1309: memset(setp, 0, howmany(state->connection_in + 1,
1.161 andreas 1310: NFDBITS) * sizeof(fd_mask));
1.201 markus 1311: FD_SET(state->connection_in, setp);
1.16 markus 1312:
1.201 markus 1313: if (state->packet_timeout_ms > 0) {
1314: ms_remain = state->packet_timeout_ms;
1.154 dtucker 1315: timeoutp = &timeout;
1316: }
1.14 markus 1317: /* Wait for some data to arrive. */
1.154 dtucker 1318: for (;;) {
1.201 markus 1319: if (state->packet_timeout_ms != -1) {
1.154 dtucker 1320: ms_to_timeval(&timeout, ms_remain);
1321: gettimeofday(&start, NULL);
1322: }
1.201 markus 1323: if ((r = select(state->connection_in + 1, setp,
1.161 andreas 1324: NULL, NULL, timeoutp)) >= 0)
1.154 dtucker 1325: break;
1.161 andreas 1326: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 1327: break;
1.201 markus 1328: if (state->packet_timeout_ms == -1)
1.154 dtucker 1329: continue;
1330: ms_subtract_diff(&start, &ms_remain);
1331: if (ms_remain <= 0) {
1.201 markus 1332: r = 0;
1.154 dtucker 1333: break;
1334: }
1335: }
1.204 djm 1336: if (r == 0)
1337: return SSH_ERR_CONN_TIMEOUT;
1.14 markus 1338: /* Read data from the socket. */
1.222 markus 1339: len = read(state->connection_in, buf, sizeof(buf));
1.210 markus 1340: if (len == 0) {
1341: r = SSH_ERR_CONN_CLOSED;
1342: goto out;
1343: }
1344: if (len < 0) {
1345: r = SSH_ERR_SYSTEM_ERROR;
1346: goto out;
1347: }
1.204 djm 1348:
1.14 markus 1349: /* Append it to the buffer. */
1.204 djm 1350: if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1.210 markus 1351: goto out;
1.14 markus 1352: }
1.210 markus 1353: out:
1.201 markus 1354: free(setp);
1355: return r;
1.1 deraadt 1356: }
1357:
1.77 djm 1358: int
1.201 markus 1359: ssh_packet_read(struct ssh *ssh)
1.77 djm 1360: {
1.201 markus 1361: u_char type;
1362: int r;
1363:
1364: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1365: fatal("%s: %s", __func__, ssh_err(r));
1366: return type;
1.77 djm 1367: }
1368:
1.16 markus 1369: /*
1370: * Waits until a packet has been received, verifies that its type matches
1371: * that given, and gives a fatal error and exits if there is a mismatch.
1372: */
1.1 deraadt 1373:
1.205 djm 1374: int
1375: ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1.1 deraadt 1376: {
1.205 djm 1377: int r;
1378: u_char type;
1.1 deraadt 1379:
1.205 djm 1380: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1381: return r;
1382: if (type != expected_type) {
1383: if ((r = sshpkt_disconnect(ssh,
1.201 markus 1384: "Protocol error: expected packet type %d, got %d",
1.205 djm 1385: expected_type, type)) != 0)
1386: return r;
1387: return SSH_ERR_PROTOCOL_ERROR;
1388: }
1389: return 0;
1.1 deraadt 1390: }
1391:
1392: /* Checks if a full packet is available in the data received so far via
1.14 markus 1393: * packet_process_incoming. If so, reads the packet; otherwise returns
1394: * SSH_MSG_NONE. This does not wait for data from the connection.
1395: *
1.150 dtucker 1396: * SSH_MSG_DISCONNECT is handled specially here. Also,
1397: * SSH_MSG_IGNORE messages are skipped by this function and are never returned
1398: * to higher levels.
1.14 markus 1399: */
1.1 deraadt 1400:
1.201 markus 1401: int
1402: ssh_packet_read_poll1(struct ssh *ssh, u_char *typep)
1.1 deraadt 1403: {
1.201 markus 1404: struct session_state *state = ssh->state;
1.40 markus 1405: u_int len, padded_len;
1.205 djm 1406: const char *emsg;
1.201 markus 1407: const u_char *cp;
1408: u_char *p;
1.40 markus 1409: u_int checksum, stored_checksum;
1.201 markus 1410: int r;
1411:
1412: *typep = SSH_MSG_NONE;
1.14 markus 1413:
1414: /* Check if input size is less than minimum packet size. */
1.201 markus 1415: if (sshbuf_len(state->input) < 4 + 8)
1416: return 0;
1.14 markus 1417: /* Get length of incoming packet. */
1.201 markus 1418: len = PEEK_U32(sshbuf_ptr(state->input));
1.205 djm 1419: if (len < 1 + 2 + 2 || len > 256 * 1024) {
1420: if ((r = sshpkt_disconnect(ssh, "Bad packet length %u",
1421: len)) != 0)
1422: return r;
1423: return SSH_ERR_CONN_CORRUPT;
1424: }
1.14 markus 1425: padded_len = (len + 8) & ~7;
1426:
1427: /* Check if the packet has been entirely received. */
1.201 markus 1428: if (sshbuf_len(state->input) < 4 + padded_len)
1429: return 0;
1.14 markus 1430:
1431: /* The entire packet is in buffer. */
1432:
1433: /* Consume packet length. */
1.201 markus 1434: if ((r = sshbuf_consume(state->input, 4)) != 0)
1435: goto out;
1.14 markus 1436:
1.62 markus 1437: /*
1438: * Cryptographic attack detector for ssh
1439: * (C)1998 CORE-SDI, Buenos Aires Argentina
1440: * Ariel Futoransky(futo@core-sdi.com)
1441: */
1.201 markus 1442: if (!state->receive_context.plaintext) {
1.205 djm 1443: emsg = NULL;
1.201 markus 1444: switch (detect_attack(&state->deattack,
1445: sshbuf_ptr(state->input), padded_len)) {
1446: case DEATTACK_OK:
1447: break;
1.144 djm 1448: case DEATTACK_DETECTED:
1.205 djm 1449: emsg = "crc32 compensation attack detected";
1450: break;
1.144 djm 1451: case DEATTACK_DOS_DETECTED:
1.205 djm 1452: emsg = "deattack denial of service detected";
1453: break;
1.201 markus 1454: default:
1.205 djm 1455: emsg = "deattack error";
1456: break;
1457: }
1458: if (emsg != NULL) {
1459: error("%s", emsg);
1460: if ((r = sshpkt_disconnect(ssh, "%s", emsg)) != 0 ||
1461: (r = ssh_packet_write_wait(ssh)) != 0)
1462: return r;
1463: return SSH_ERR_CONN_CORRUPT;
1.144 djm 1464: }
1465: }
1.62 markus 1466:
1467: /* Decrypt data to incoming_packet. */
1.201 markus 1468: sshbuf_reset(state->incoming_packet);
1469: if ((r = sshbuf_reserve(state->incoming_packet, padded_len, &p)) != 0)
1470: goto out;
1471: if ((r = cipher_crypt(&state->receive_context, 0, p,
1472: sshbuf_ptr(state->input), padded_len, 0, 0)) != 0)
1473: goto out;
1.62 markus 1474:
1.201 markus 1475: if ((r = sshbuf_consume(state->input, padded_len)) != 0)
1476: goto out;
1.1 deraadt 1477:
1478: #ifdef PACKET_DEBUG
1.14 markus 1479: fprintf(stderr, "read_poll plain: ");
1.201 markus 1480: sshbuf_dump(state->incoming_packet, stderr);
1.1 deraadt 1481: #endif
1482:
1.14 markus 1483: /* Compute packet checksum. */
1.201 markus 1484: checksum = ssh_crc32(sshbuf_ptr(state->incoming_packet),
1485: sshbuf_len(state->incoming_packet) - 4);
1.14 markus 1486:
1487: /* Skip padding. */
1.201 markus 1488: if ((r = sshbuf_consume(state->incoming_packet, 8 - len % 8)) != 0)
1489: goto out;
1.14 markus 1490:
1491: /* Test check bytes. */
1.205 djm 1492: if (len != sshbuf_len(state->incoming_packet)) {
1493: error("%s: len %d != sshbuf_len %zd", __func__,
1.201 markus 1494: len, sshbuf_len(state->incoming_packet));
1.205 djm 1495: if ((r = sshpkt_disconnect(ssh, "invalid packet length")) != 0 ||
1496: (r = ssh_packet_write_wait(ssh)) != 0)
1497: return r;
1498: return SSH_ERR_CONN_CORRUPT;
1499: }
1.14 markus 1500:
1.201 markus 1501: cp = sshbuf_ptr(state->incoming_packet) + len - 4;
1502: stored_checksum = PEEK_U32(cp);
1.205 djm 1503: if (checksum != stored_checksum) {
1504: error("Corrupted check bytes on input");
1505: if ((r = sshpkt_disconnect(ssh, "connection corrupted")) != 0 ||
1506: (r = ssh_packet_write_wait(ssh)) != 0)
1507: return r;
1508: return SSH_ERR_CONN_CORRUPT;
1509: }
1.201 markus 1510: if ((r = sshbuf_consume_end(state->incoming_packet, 4)) < 0)
1511: goto out;
1512:
1513: if (state->packet_compression) {
1514: sshbuf_reset(state->compression_buffer);
1515: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1516: state->compression_buffer)) != 0)
1517: goto out;
1518: sshbuf_reset(state->incoming_packet);
1519: if ((r = sshbuf_putb(state->incoming_packet,
1520: state->compression_buffer)) != 0)
1521: goto out;
1522: }
1523: state->p_read.packets++;
1524: state->p_read.bytes += padded_len + 4;
1525: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1526: goto out;
1.205 djm 1527: if (*typep < SSH_MSG_MIN || *typep > SSH_MSG_MAX) {
1528: error("Invalid ssh1 packet type: %d", *typep);
1529: if ((r = sshpkt_disconnect(ssh, "invalid packet type")) != 0 ||
1530: (r = ssh_packet_write_wait(ssh)) != 0)
1531: return r;
1532: return SSH_ERR_PROTOCOL_ERROR;
1533: }
1.201 markus 1534: r = 0;
1535: out:
1536: return r;
1.1 deraadt 1537: }
1.14 markus 1538:
1.201 markus 1539: int
1540: ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1541: {
1.201 markus 1542: struct session_state *state = ssh->state;
1.40 markus 1543: u_int padlen, need;
1.201 markus 1544: u_char *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1545: u_int maclen, aadlen = 0, authlen = 0, block_size;
1546: struct sshenc *enc = NULL;
1547: struct sshmac *mac = NULL;
1548: struct sshcomp *comp = NULL;
1.200 markus 1549: int r;
1.201 markus 1550:
1551: *typep = SSH_MSG_NONE;
1552:
1553: if (state->packet_discard)
1554: return 0;
1555:
1556: if (state->newkeys[MODE_IN] != NULL) {
1557: enc = &state->newkeys[MODE_IN]->enc;
1558: mac = &state->newkeys[MODE_IN]->mac;
1559: comp = &state->newkeys[MODE_IN]->comp;
1.180 markus 1560: /* disable mac for authenticated encryption */
1561: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1562: mac = NULL;
1.25 markus 1563: }
1564: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.88 markus 1565: block_size = enc ? enc->block_size : 8;
1.180 markus 1566: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1567:
1.201 markus 1568: if (aadlen && state->packlen == 0) {
1569: if (cipher_get_length(&state->receive_context,
1570: &state->packlen, state->p_read.seqnr,
1571: sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1572: return 0;
1573: if (state->packlen < 1 + 4 ||
1574: state->packlen > PACKET_MAX_SIZE) {
1.178 markus 1575: #ifdef PACKET_DEBUG
1.201 markus 1576: sshbuf_dump(state->input, stderr);
1.178 markus 1577: #endif
1.201 markus 1578: logit("Bad packet length %u.", state->packlen);
1579: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1580: return r;
1.217 djm 1581: return SSH_ERR_CONN_CORRUPT;
1.178 markus 1582: }
1.201 markus 1583: sshbuf_reset(state->incoming_packet);
1584: } else if (state->packlen == 0) {
1.25 markus 1585: /*
1586: * check if input size is less than the cipher block size,
1587: * decrypt first block and extract length of incoming packet
1588: */
1.201 markus 1589: if (sshbuf_len(state->input) < block_size)
1590: return 0;
1591: sshbuf_reset(state->incoming_packet);
1592: if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1593: &cp)) != 0)
1594: goto out;
1595: if ((r = cipher_crypt(&state->receive_context,
1596: state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1597: block_size, 0, 0)) != 0)
1598: goto out;
1599: state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1600: if (state->packlen < 1 + 4 ||
1601: state->packlen > PACKET_MAX_SIZE) {
1.110 markus 1602: #ifdef PACKET_DEBUG
1.201 markus 1603: fprintf(stderr, "input: \n");
1604: sshbuf_dump(state->input, stderr);
1605: fprintf(stderr, "incoming_packet: \n");
1606: sshbuf_dump(state->incoming_packet, stderr);
1.110 markus 1607: #endif
1.201 markus 1608: logit("Bad packet length %u.", state->packlen);
1609: return ssh_packet_start_discard(ssh, enc, mac,
1610: state->packlen, PACKET_MAX_SIZE);
1.25 markus 1611: }
1.201 markus 1612: if ((r = sshbuf_consume(state->input, block_size)) != 0)
1613: goto out;
1.25 markus 1614: }
1.201 markus 1615: DBG(debug("input: packet len %u", state->packlen+4));
1616:
1.178 markus 1617: if (aadlen) {
1618: /* only the payload is encrypted */
1.201 markus 1619: need = state->packlen;
1.178 markus 1620: } else {
1621: /*
1622: * the payload size and the payload are encrypted, but we
1623: * have a partial packet of block_size bytes
1624: */
1.201 markus 1625: need = 4 + state->packlen - block_size;
1.178 markus 1626: }
1.180 markus 1627: DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1628: " aadlen %d", block_size, need, maclen, authlen, aadlen));
1.158 markus 1629: if (need % block_size != 0) {
1630: logit("padding error: need %d block %d mod %d",
1.25 markus 1631: need, block_size, need % block_size);
1.201 markus 1632: return ssh_packet_start_discard(ssh, enc, mac,
1633: state->packlen, PACKET_MAX_SIZE - block_size);
1.158 markus 1634: }
1.25 markus 1635: /*
1636: * check if the entire packet has been received and
1.178 markus 1637: * decrypt into incoming_packet:
1638: * 'aadlen' bytes are unencrypted, but authenticated.
1.180 markus 1639: * 'need' bytes are encrypted, followed by either
1640: * 'authlen' bytes of authentication tag or
1.178 markus 1641: * 'maclen' bytes of message authentication code.
1.25 markus 1642: */
1.201 markus 1643: if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1644: return 0;
1.25 markus 1645: #ifdef PACKET_DEBUG
1646: fprintf(stderr, "read_poll enc/full: ");
1.201 markus 1647: sshbuf_dump(state->input, stderr);
1.25 markus 1648: #endif
1.178 markus 1649: /* EtM: compute mac over encrypted input */
1.201 markus 1650: if (mac && mac->enabled && mac->etm) {
1651: if ((r = mac_compute(mac, state->p_read.seqnr,
1652: sshbuf_ptr(state->input), aadlen + need,
1.200 markus 1653: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1654: goto out;
1655: }
1656: if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1657: &cp)) != 0)
1658: goto out;
1659: if ((r = cipher_crypt(&state->receive_context, state->p_read.seqnr, cp,
1660: sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1661: goto out;
1662: if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1663: goto out;
1.25 markus 1664: /*
1665: * compute MAC over seqnr and packet,
1666: * increment sequence number for incoming packet
1667: */
1.29 markus 1668: if (mac && mac->enabled) {
1.178 markus 1669: if (!mac->etm)
1.201 markus 1670: if ((r = mac_compute(mac, state->p_read.seqnr,
1671: sshbuf_ptr(state->incoming_packet),
1672: sshbuf_len(state->incoming_packet),
1.200 markus 1673: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1674: goto out;
1675: if (timingsafe_bcmp(macbuf, sshbuf_ptr(state->input),
1.161 andreas 1676: mac->mac_len) != 0) {
1.159 markus 1677: logit("Corrupted MAC on input.");
1678: if (need > PACKET_MAX_SIZE)
1.201 markus 1679: return SSH_ERR_INTERNAL_ERROR;
1680: return ssh_packet_start_discard(ssh, enc, mac,
1681: state->packlen, PACKET_MAX_SIZE - need);
1682: }
1683:
1684: DBG(debug("MAC #%d ok", state->p_read.seqnr));
1685: if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1686: goto out;
1.25 markus 1687: }
1.77 djm 1688: if (seqnr_p != NULL)
1.201 markus 1689: *seqnr_p = state->p_read.seqnr;
1690: if (++state->p_read.seqnr == 0)
1.106 itojun 1691: logit("incoming seqnr wraps around");
1.201 markus 1692: if (++state->p_read.packets == 0)
1693: if (!(ssh->compat & SSH_BUG_NOREKEY))
1694: return SSH_ERR_NEED_REKEY;
1695: state->p_read.blocks += (state->packlen + 4) / block_size;
1696: state->p_read.bytes += state->packlen + 4;
1.25 markus 1697:
1698: /* get padlen */
1.201 markus 1699: padlen = sshbuf_ptr(state->incoming_packet)[4];
1.25 markus 1700: DBG(debug("input: padlen %d", padlen));
1.205 djm 1701: if (padlen < 4) {
1702: if ((r = sshpkt_disconnect(ssh,
1703: "Corrupted padlen %d on input.", padlen)) != 0 ||
1704: (r = ssh_packet_write_wait(ssh)) != 0)
1705: return r;
1706: return SSH_ERR_CONN_CORRUPT;
1707: }
1.25 markus 1708:
1709: /* skip packet size + padlen, discard padding */
1.201 markus 1710: if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1711: ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1712: goto out;
1.25 markus 1713:
1.201 markus 1714: DBG(debug("input: len before de-compress %zd",
1715: sshbuf_len(state->incoming_packet)));
1.25 markus 1716: if (comp && comp->enabled) {
1.201 markus 1717: sshbuf_reset(state->compression_buffer);
1718: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1719: state->compression_buffer)) != 0)
1720: goto out;
1721: sshbuf_reset(state->incoming_packet);
1722: if ((r = sshbuf_putb(state->incoming_packet,
1723: state->compression_buffer)) != 0)
1724: goto out;
1725: DBG(debug("input: len after de-compress %zd",
1726: sshbuf_len(state->incoming_packet)));
1.25 markus 1727: }
1728: /*
1729: * get packet type, implies consume.
1730: * return length of payload (without type field)
1731: */
1.201 markus 1732: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1733: goto out;
1.205 djm 1734: if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1735: if ((r = sshpkt_disconnect(ssh,
1736: "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1737: (r = ssh_packet_write_wait(ssh)) != 0)
1738: return r;
1739: return SSH_ERR_PROTOCOL_ERROR;
1740: }
1.201 markus 1741: if (*typep == SSH2_MSG_NEWKEYS)
1742: r = ssh_set_newkeys(ssh, MODE_IN);
1743: else if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1744: r = ssh_packet_enable_delayed_compress(ssh);
1745: else
1746: r = 0;
1.25 markus 1747: #ifdef PACKET_DEBUG
1.201 markus 1748: fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1749: sshbuf_dump(state->incoming_packet, stderr);
1.25 markus 1750: #endif
1.62 markus 1751: /* reset for next packet */
1.201 markus 1752: state->packlen = 0;
1753: out:
1754: return r;
1.25 markus 1755: }
1756:
1757: int
1.201 markus 1758: ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1759: {
1.201 markus 1760: struct session_state *state = ssh->state;
1.96 deraadt 1761: u_int reason, seqnr;
1.201 markus 1762: int r;
1763: u_char *msg;
1.62 markus 1764:
1.25 markus 1765: for (;;) {
1.201 markus 1766: msg = NULL;
1.62 markus 1767: if (compat20) {
1.201 markus 1768: r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1769: if (r != 0)
1770: return r;
1771: if (*typep) {
1772: state->keep_alive_timeouts = 0;
1773: DBG(debug("received packet type %d", *typep));
1.153 djm 1774: }
1.201 markus 1775: switch (*typep) {
1.150 dtucker 1776: case SSH2_MSG_IGNORE:
1.151 dtucker 1777: debug3("Received SSH2_MSG_IGNORE");
1.150 dtucker 1778: break;
1.25 markus 1779: case SSH2_MSG_DEBUG:
1.201 markus 1780: if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1781: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1782: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1.219 mmcc 1783: free(msg);
1.201 markus 1784: return r;
1785: }
1.25 markus 1786: debug("Remote: %.900s", msg);
1.186 djm 1787: free(msg);
1.25 markus 1788: break;
1789: case SSH2_MSG_DISCONNECT:
1.201 markus 1790: if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1791: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1792: return r;
1.182 djm 1793: /* Ignore normal client exit notifications */
1.201 markus 1794: do_log2(ssh->state->server_side &&
1.182 djm 1795: reason == SSH2_DISCONNECT_BY_APPLICATION ?
1796: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1.220 djm 1797: "Received disconnect from %s port %d:"
1798: "%u: %.400s", ssh_remote_ipaddr(ssh),
1799: ssh_remote_port(ssh), reason, msg);
1.186 djm 1800: free(msg);
1.201 markus 1801: return SSH_ERR_DISCONNECTED;
1.84 markus 1802: case SSH2_MSG_UNIMPLEMENTED:
1.201 markus 1803: if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1804: return r;
1.96 deraadt 1805: debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1806: seqnr);
1.150 dtucker 1807: break;
1.25 markus 1808: default:
1.201 markus 1809: return 0;
1.48 stevesk 1810: }
1.25 markus 1811: } else {
1.201 markus 1812: r = ssh_packet_read_poll1(ssh, typep);
1813: switch (*typep) {
1.188 djm 1814: case SSH_MSG_NONE:
1815: return SSH_MSG_NONE;
1.25 markus 1816: case SSH_MSG_IGNORE:
1817: break;
1818: case SSH_MSG_DEBUG:
1.201 markus 1819: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1820: return r;
1.25 markus 1821: debug("Remote: %.900s", msg);
1.186 djm 1822: free(msg);
1.25 markus 1823: break;
1824: case SSH_MSG_DISCONNECT:
1.201 markus 1825: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1826: return r;
1.220 djm 1827: error("Received disconnect from %s port %d: "
1828: "%.400s", ssh_remote_ipaddr(ssh),
1829: ssh_remote_port(ssh), msg);
1.201 markus 1830: free(msg);
1831: return SSH_ERR_DISCONNECTED;
1.25 markus 1832: default:
1.201 markus 1833: DBG(debug("received packet type %d", *typep));
1834: return 0;
1.48 stevesk 1835: }
1.25 markus 1836: }
1837: }
1838: }
1839:
1.16 markus 1840: /*
1841: * Buffers the given amount of input characters. This is intended to be used
1842: * together with packet_read_poll.
1843: */
1.1 deraadt 1844:
1.204 djm 1845: int
1.201 markus 1846: ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1.1 deraadt 1847: {
1.201 markus 1848: struct session_state *state = ssh->state;
1849: int r;
1850:
1851: if (state->packet_discard) {
1852: state->keep_alive_timeouts = 0; /* ?? */
1853: if (len >= state->packet_discard) {
1854: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1.204 djm 1855: return r;
1.201 markus 1856: }
1857: state->packet_discard -= len;
1.204 djm 1858: return 0;
1.159 markus 1859: }
1.201 markus 1860: if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1.204 djm 1861: return r;
1862:
1863: return 0;
1.28 markus 1864: }
1865:
1866: int
1.201 markus 1867: ssh_packet_remaining(struct ssh *ssh)
1.28 markus 1868: {
1.201 markus 1869: return sshbuf_len(ssh->state->incoming_packet);
1.1 deraadt 1870: }
1871:
1.16 markus 1872: /*
1873: * Sends a diagnostic message from the server to the client. This message
1874: * can be sent at any time (but not while constructing another message). The
1875: * message is printed immediately, but only if the client is being executed
1876: * in verbose mode. These messages are primarily intended to ease debugging
1877: * authentication problems. The length of the formatted message must not
1.205 djm 1878: * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1.16 markus 1879: */
1.2 provos 1880: void
1.201 markus 1881: ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1882: {
1.14 markus 1883: char buf[1024];
1884: va_list args;
1.201 markus 1885: int r;
1.39 markus 1886:
1.201 markus 1887: if (compat20 && (ssh->compat & SSH_BUG_DEBUG))
1.39 markus 1888: return;
1.14 markus 1889:
1890: va_start(args, fmt);
1891: vsnprintf(buf, sizeof(buf), fmt, args);
1892: va_end(args);
1893:
1.30 markus 1894: if (compat20) {
1.201 markus 1895: if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1896: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1897: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1898: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1899: (r = sshpkt_send(ssh)) != 0)
1900: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1901: } else {
1.201 markus 1902: if ((r = sshpkt_start(ssh, SSH_MSG_DEBUG)) != 0 ||
1903: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1904: (r = sshpkt_send(ssh)) != 0)
1905: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1906: }
1.205 djm 1907: if ((r = ssh_packet_write_wait(ssh)) != 0)
1908: fatal("%s: %s", __func__, ssh_err(r));
1909: }
1910:
1911: /*
1912: * Pretty-print connection-terminating errors and exit.
1913: */
1914: void
1915: sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1916: {
1917: switch (r) {
1918: case SSH_ERR_CONN_CLOSED:
1.220 djm 1919: logit("Connection closed by %.200s port %d",
1920: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.205 djm 1921: cleanup_exit(255);
1922: case SSH_ERR_CONN_TIMEOUT:
1.220 djm 1923: logit("Connection %s %.200s port %d timed out",
1924: ssh->state->server_side ? "from" : "to",
1925: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.205 djm 1926: cleanup_exit(255);
1.212 djm 1927: case SSH_ERR_DISCONNECTED:
1.220 djm 1928: logit("Disconnected from %.200s port %d",
1929: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 1930: cleanup_exit(255);
1931: case SSH_ERR_SYSTEM_ERROR:
1932: if (errno == ECONNRESET) {
1.220 djm 1933: logit("Connection reset by %.200s port %d",
1934: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 1935: cleanup_exit(255);
1.213 djm 1936: }
1937: /* FALLTHROUGH */
1938: case SSH_ERR_NO_CIPHER_ALG_MATCH:
1939: case SSH_ERR_NO_MAC_ALG_MATCH:
1940: case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1941: case SSH_ERR_NO_KEX_ALG_MATCH:
1942: case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1943: if (ssh && ssh->kex && ssh->kex->failed_choice) {
1.220 djm 1944: fatal("Unable to negotiate with %.200s port %d: %s. "
1.213 djm 1945: "Their offer: %s", ssh_remote_ipaddr(ssh),
1.220 djm 1946: ssh_remote_port(ssh), ssh_err(r),
1947: ssh->kex->failed_choice);
1.212 djm 1948: }
1949: /* FALLTHROUGH */
1.205 djm 1950: default:
1.220 djm 1951: fatal("%s%sConnection %s %.200s port %d: %s",
1.205 djm 1952: tag != NULL ? tag : "", tag != NULL ? ": " : "",
1.220 djm 1953: ssh->state->server_side ? "from" : "to",
1954: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), ssh_err(r));
1.205 djm 1955: }
1.1 deraadt 1956: }
1957:
1.16 markus 1958: /*
1959: * Logs the error plus constructs and sends a disconnect packet, closes the
1960: * connection, and exits. This function never returns. The error message
1961: * should not contain a newline. The length of the formatted message must
1962: * not exceed 1024 bytes.
1963: */
1.2 provos 1964: void
1.201 markus 1965: ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1966: {
1.14 markus 1967: char buf[1024];
1968: va_list args;
1969: static int disconnecting = 0;
1.201 markus 1970: int r;
1.97 deraadt 1971:
1.14 markus 1972: if (disconnecting) /* Guard against recursive invocations. */
1973: fatal("packet_disconnect called recursively.");
1974: disconnecting = 1;
1975:
1.16 markus 1976: /*
1977: * Format the message. Note that the caller must make sure the
1978: * message is of limited size.
1979: */
1.14 markus 1980: va_start(args, fmt);
1981: vsnprintf(buf, sizeof(buf), fmt, args);
1982: va_end(args);
1983:
1.99 markus 1984: /* Display the error locally */
1.106 itojun 1985: logit("Disconnecting: %.100s", buf);
1.99 markus 1986:
1.205 djm 1987: /*
1988: * Send the disconnect message to the other side, and wait
1989: * for it to get sent.
1990: */
1991: if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1992: sshpkt_fatal(ssh, __func__, r);
1993:
1994: if ((r = ssh_packet_write_wait(ssh)) != 0)
1995: sshpkt_fatal(ssh, __func__, r);
1.14 markus 1996:
1997: /* Close the connection. */
1.201 markus 1998: ssh_packet_close(ssh);
1.112 markus 1999: cleanup_exit(255);
1.1 deraadt 2000: }
2001:
1.205 djm 2002: /*
2003: * Checks if there is any buffered output, and tries to write some of
2004: * the output.
2005: */
2006: int
1.201 markus 2007: ssh_packet_write_poll(struct ssh *ssh)
1.1 deraadt 2008: {
1.201 markus 2009: struct session_state *state = ssh->state;
2010: int len = sshbuf_len(state->output);
1.222 markus 2011: int r;
1.97 deraadt 2012:
1.14 markus 2013: if (len > 0) {
1.222 markus 2014: len = write(state->connection_out,
2015: sshbuf_ptr(state->output), len);
1.156 djm 2016: if (len == -1) {
2017: if (errno == EINTR || errno == EAGAIN)
1.205 djm 2018: return 0;
2019: return SSH_ERR_SYSTEM_ERROR;
1.14 markus 2020: }
1.222 markus 2021: if (len == 0)
1.205 djm 2022: return SSH_ERR_CONN_CLOSED;
1.201 markus 2023: if ((r = sshbuf_consume(state->output, len)) != 0)
1.205 djm 2024: return r;
1.14 markus 2025: }
1.205 djm 2026: return 0;
1.1 deraadt 2027: }
2028:
1.16 markus 2029: /*
2030: * Calls packet_write_poll repeatedly until all pending output data has been
2031: * written.
2032: */
1.205 djm 2033: int
1.201 markus 2034: ssh_packet_write_wait(struct ssh *ssh)
1.1 deraadt 2035: {
1.56 millert 2036: fd_set *setp;
1.205 djm 2037: int ret, r, ms_remain = 0;
1.154 dtucker 2038: struct timeval start, timeout, *timeoutp = NULL;
1.201 markus 2039: struct session_state *state = ssh->state;
1.56 millert 2040:
1.214 deraadt 2041: setp = calloc(howmany(state->connection_out + 1,
1.161 andreas 2042: NFDBITS), sizeof(fd_mask));
1.201 markus 2043: if (setp == NULL)
1.205 djm 2044: return SSH_ERR_ALLOC_FAIL;
1.216 gsoares 2045: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2046: free(setp);
1.215 djm 2047: return r;
1.216 gsoares 2048: }
1.201 markus 2049: while (ssh_packet_have_data_to_write(ssh)) {
2050: memset(setp, 0, howmany(state->connection_out + 1,
1.161 andreas 2051: NFDBITS) * sizeof(fd_mask));
1.201 markus 2052: FD_SET(state->connection_out, setp);
1.154 dtucker 2053:
1.201 markus 2054: if (state->packet_timeout_ms > 0) {
2055: ms_remain = state->packet_timeout_ms;
1.154 dtucker 2056: timeoutp = &timeout;
2057: }
2058: for (;;) {
1.201 markus 2059: if (state->packet_timeout_ms != -1) {
1.154 dtucker 2060: ms_to_timeval(&timeout, ms_remain);
2061: gettimeofday(&start, NULL);
2062: }
1.201 markus 2063: if ((ret = select(state->connection_out + 1,
1.161 andreas 2064: NULL, setp, NULL, timeoutp)) >= 0)
1.154 dtucker 2065: break;
1.161 andreas 2066: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 2067: break;
1.201 markus 2068: if (state->packet_timeout_ms == -1)
1.154 dtucker 2069: continue;
2070: ms_subtract_diff(&start, &ms_remain);
2071: if (ms_remain <= 0) {
2072: ret = 0;
2073: break;
2074: }
2075: }
2076: if (ret == 0) {
1.205 djm 2077: free(setp);
2078: return SSH_ERR_CONN_TIMEOUT;
2079: }
2080: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2081: free(setp);
2082: return r;
1.154 dtucker 2083: }
1.14 markus 2084: }
1.186 djm 2085: free(setp);
1.205 djm 2086: return 0;
1.1 deraadt 2087: }
2088:
2089: /* Returns true if there is buffered data to write to the connection. */
2090:
1.2 provos 2091: int
1.201 markus 2092: ssh_packet_have_data_to_write(struct ssh *ssh)
1.1 deraadt 2093: {
1.201 markus 2094: return sshbuf_len(ssh->state->output) != 0;
1.1 deraadt 2095: }
2096:
2097: /* Returns true if there is not too much data to write to the connection. */
2098:
1.2 provos 2099: int
1.201 markus 2100: ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1.1 deraadt 2101: {
1.201 markus 2102: if (ssh->state->interactive_mode)
2103: return sshbuf_len(ssh->state->output) < 16384;
1.14 markus 2104: else
1.201 markus 2105: return sshbuf_len(ssh->state->output) < 128 * 1024;
1.1 deraadt 2106: }
2107:
1.201 markus 2108: void
2109: ssh_packet_set_tos(struct ssh *ssh, int tos)
1.101 markus 2110: {
1.201 markus 2111: if (!ssh_packet_connection_is_on_socket(ssh))
1.101 markus 2112: return;
1.201 markus 2113: switch (ssh_packet_connection_af(ssh)) {
1.173 djm 2114: case AF_INET:
2115: debug3("%s: set IP_TOS 0x%02x", __func__, tos);
1.201 markus 2116: if (setsockopt(ssh->state->connection_in,
1.173 djm 2117: IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2118: error("setsockopt IP_TOS %d: %.100s:",
2119: tos, strerror(errno));
2120: break;
2121: case AF_INET6:
2122: debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
1.201 markus 2123: if (setsockopt(ssh->state->connection_in,
1.173 djm 2124: IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2125: error("setsockopt IPV6_TCLASS %d: %.100s:",
2126: tos, strerror(errno));
2127: break;
2128: }
1.101 markus 2129: }
2130:
1.1 deraadt 2131: /* Informs that the current session is interactive. Sets IP flags for that. */
2132:
1.2 provos 2133: void
1.201 markus 2134: ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
1.1 deraadt 2135: {
1.201 markus 2136: struct session_state *state = ssh->state;
2137:
2138: if (state->set_interactive_called)
1.43 markus 2139: return;
1.201 markus 2140: state->set_interactive_called = 1;
1.1 deraadt 2141:
1.14 markus 2142: /* Record that we are in interactive mode. */
1.201 markus 2143: state->interactive_mode = interactive;
1.1 deraadt 2144:
1.19 markus 2145: /* Only set socket options if using a socket. */
1.201 markus 2146: if (!ssh_packet_connection_is_on_socket(ssh))
1.14 markus 2147: return;
1.201 markus 2148: set_nodelay(state->connection_in);
2149: ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2150: qos_bulk);
1.1 deraadt 2151: }
2152:
2153: /* Returns true if the current connection is interactive. */
2154:
1.2 provos 2155: int
1.201 markus 2156: ssh_packet_is_interactive(struct ssh *ssh)
1.1 deraadt 2157: {
1.201 markus 2158: return ssh->state->interactive_mode;
1.12 markus 2159: }
2160:
1.113 deraadt 2161: int
1.201 markus 2162: ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
1.12 markus 2163: {
1.201 markus 2164: struct session_state *state = ssh->state;
2165:
2166: if (state->set_maxsize_called) {
1.106 itojun 2167: logit("packet_set_maxsize: called twice: old %d new %d",
1.201 markus 2168: state->max_packet_size, s);
1.14 markus 2169: return -1;
2170: }
2171: if (s < 4 * 1024 || s > 1024 * 1024) {
1.106 itojun 2172: logit("packet_set_maxsize: bad size %d", s);
1.14 markus 2173: return -1;
2174: }
1.201 markus 2175: state->set_maxsize_called = 1;
1.66 markus 2176: debug("packet_set_maxsize: setting to %d", s);
1.201 markus 2177: state->max_packet_size = s;
1.14 markus 2178: return s;
1.53 markus 2179: }
2180:
1.161 andreas 2181: int
1.201 markus 2182: ssh_packet_inc_alive_timeouts(struct ssh *ssh)
1.161 andreas 2183: {
1.201 markus 2184: return ++ssh->state->keep_alive_timeouts;
1.161 andreas 2185: }
2186:
2187: void
1.201 markus 2188: ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
1.161 andreas 2189: {
1.201 markus 2190: ssh->state->keep_alive_timeouts = ka;
1.161 andreas 2191: }
2192:
2193: u_int
1.201 markus 2194: ssh_packet_get_maxsize(struct ssh *ssh)
1.71 markus 2195: {
1.201 markus 2196: return ssh->state->max_packet_size;
1.71 markus 2197: }
2198:
1.53 markus 2199: /*
2200: * 9.2. Ignored Data Message
1.61 markus 2201: *
1.53 markus 2202: * byte SSH_MSG_IGNORE
2203: * string data
1.61 markus 2204: *
1.53 markus 2205: * All implementations MUST understand (and ignore) this message at any
2206: * time (after receiving the protocol version). No implementation is
2207: * required to send them. This message can be used as an additional
2208: * protection measure against advanced traffic analysis techniques.
2209: */
1.54 markus 2210: void
1.201 markus 2211: ssh_packet_send_ignore(struct ssh *ssh, int nbytes)
1.54 markus 2212: {
1.115 avsm 2213: u_int32_t rnd = 0;
1.201 markus 2214: int r, i;
1.54 markus 2215:
1.201 markus 2216: if ((r = sshpkt_start(ssh, compat20 ?
2217: SSH2_MSG_IGNORE : SSH_MSG_IGNORE)) != 0 ||
2218: (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2219: fatal("%s: %s", __func__, ssh_err(r));
1.75 deraadt 2220: for (i = 0; i < nbytes; i++) {
1.53 markus 2221: if (i % 4 == 0)
1.115 avsm 2222: rnd = arc4random();
1.201 markus 2223: if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2224: fatal("%s: %s", __func__, ssh_err(r));
1.115 avsm 2225: rnd >>= 8;
1.53 markus 2226: }
1.105 markus 2227: }
2228:
1.113 deraadt 2229: #define MAX_PACKETS (1U<<31)
1.105 markus 2230: int
1.201 markus 2231: ssh_packet_need_rekeying(struct ssh *ssh)
1.105 markus 2232: {
1.201 markus 2233: struct session_state *state = ssh->state;
1.223 ! dtucker 2234: u_int32_t buf_in, buf_out;
1.201 markus 2235:
2236: if (ssh->compat & SSH_BUG_NOREKEY)
1.105 markus 2237: return 0;
1.223 ! dtucker 2238: buf_in = roundup(sshbuf_len(state->input),
! 2239: state->newkeys[MODE_IN]->enc.block_size);
! 2240: buf_out = roundup(sshbuf_len(state->output),
! 2241: state->newkeys[MODE_OUT]->enc.block_size);
1.105 markus 2242: return
1.201 markus 2243: (state->p_send.packets > MAX_PACKETS) ||
2244: (state->p_read.packets > MAX_PACKETS) ||
2245: (state->max_blocks_out &&
1.223 ! dtucker 2246: (state->p_send.blocks + buf_out > state->max_blocks_out)) ||
1.201 markus 2247: (state->max_blocks_in &&
1.223 ! dtucker 2248: (state->p_read.blocks + buf_in > state->max_blocks_in)) ||
1.201 markus 2249: (state->rekey_interval != 0 && state->rekey_time +
2250: state->rekey_interval <= monotime());
1.105 markus 2251: }
2252:
2253: void
1.201 markus 2254: ssh_packet_set_rekey_limits(struct ssh *ssh, u_int32_t bytes, time_t seconds)
1.105 markus 2255: {
1.184 dtucker 2256: debug3("rekey after %lld bytes, %d seconds", (long long)bytes,
2257: (int)seconds);
1.201 markus 2258: ssh->state->rekey_limit = bytes;
2259: ssh->state->rekey_interval = seconds;
1.184 dtucker 2260: }
2261:
2262: time_t
1.201 markus 2263: ssh_packet_get_rekey_timeout(struct ssh *ssh)
1.184 dtucker 2264: {
2265: time_t seconds;
2266:
1.201 markus 2267: seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
1.187 dtucker 2268: monotime();
1.185 dtucker 2269: return (seconds <= 0 ? 1 : seconds);
1.118 markus 2270: }
2271:
2272: void
1.201 markus 2273: ssh_packet_set_server(struct ssh *ssh)
1.118 markus 2274: {
1.201 markus 2275: ssh->state->server_side = 1;
1.118 markus 2276: }
2277:
2278: void
1.201 markus 2279: ssh_packet_set_authenticated(struct ssh *ssh)
1.118 markus 2280: {
1.201 markus 2281: ssh->state->after_authentication = 1;
1.161 andreas 2282: }
2283:
2284: void *
1.201 markus 2285: ssh_packet_get_input(struct ssh *ssh)
1.161 andreas 2286: {
1.201 markus 2287: return (void *)ssh->state->input;
1.161 andreas 2288: }
2289:
2290: void *
1.201 markus 2291: ssh_packet_get_output(struct ssh *ssh)
1.161 andreas 2292: {
1.201 markus 2293: return (void *)ssh->state->output;
1.166 andreas 2294: }
2295:
1.196 markus 2296: /* Reset after_authentication and reset compression in post-auth privsep */
1.201 markus 2297: static int
2298: ssh_packet_set_postauth(struct ssh *ssh)
1.196 markus 2299: {
1.201 markus 2300: struct sshcomp *comp;
2301: int r, mode;
1.196 markus 2302:
2303: debug("%s: called", __func__);
2304: /* This was set in net child, but is not visible in user child */
1.201 markus 2305: ssh->state->after_authentication = 1;
2306: ssh->state->rekeying = 0;
1.196 markus 2307: for (mode = 0; mode < MODE_MAX; mode++) {
1.201 markus 2308: if (ssh->state->newkeys[mode] == NULL)
1.196 markus 2309: continue;
1.201 markus 2310: comp = &ssh->state->newkeys[mode]->comp;
2311: if (comp && comp->enabled &&
2312: (r = ssh_packet_init_compression(ssh)) != 0)
2313: return r;
2314: }
2315: return 0;
2316: }
2317:
2318: /* Packet state (de-)serialization for privsep */
2319:
2320: /* turn kex into a blob for packet state serialization */
2321: static int
2322: kex_to_blob(struct sshbuf *m, struct kex *kex)
2323: {
2324: int r;
2325:
2326: if ((r = sshbuf_put_string(m, kex->session_id,
2327: kex->session_id_len)) != 0 ||
2328: (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2329: (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2330: (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2331: (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2332: (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2333: (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2334: (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2335: (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2336: return r;
2337: return 0;
2338: }
2339:
2340: /* turn key exchange results into a blob for packet state serialization */
2341: static int
2342: newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2343: {
2344: struct sshbuf *b;
2345: struct sshcipher_ctx *cc;
2346: struct sshcomp *comp;
2347: struct sshenc *enc;
2348: struct sshmac *mac;
2349: struct newkeys *newkey;
2350: int r;
2351:
2352: if ((newkey = ssh->state->newkeys[mode]) == NULL)
2353: return SSH_ERR_INTERNAL_ERROR;
2354: enc = &newkey->enc;
2355: mac = &newkey->mac;
2356: comp = &newkey->comp;
2357: cc = (mode == MODE_OUT) ? &ssh->state->send_context :
2358: &ssh->state->receive_context;
2359: if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2360: return r;
2361: if ((b = sshbuf_new()) == NULL)
2362: return SSH_ERR_ALLOC_FAIL;
2363: /* The cipher struct is constant and shared, you export pointer */
2364: if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2365: (r = sshbuf_put(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2366: (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2367: (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2368: (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2369: (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2370: goto out;
2371: if (cipher_authlen(enc->cipher) == 0) {
2372: if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2373: (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2374: (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2375: goto out;
2376: }
2377: if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2378: (r = sshbuf_put_u32(b, comp->enabled)) != 0 ||
2379: (r = sshbuf_put_cstring(b, comp->name)) != 0)
2380: goto out;
2381: r = sshbuf_put_stringb(m, b);
2382: out:
1.221 mmcc 2383: sshbuf_free(b);
1.201 markus 2384: return r;
2385: }
2386:
2387: /* serialize packet state into a blob */
2388: int
2389: ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2390: {
2391: struct session_state *state = ssh->state;
2392: u_char *p;
2393: size_t slen, rlen;
2394: int r, ssh1cipher;
2395:
2396: if (!compat20) {
2397: ssh1cipher = cipher_get_number(state->receive_context.cipher);
2398: slen = cipher_get_keyiv_len(&state->send_context);
2399: rlen = cipher_get_keyiv_len(&state->receive_context);
2400: if ((r = sshbuf_put_u32(m, state->remote_protocol_flags)) != 0 ||
2401: (r = sshbuf_put_u32(m, ssh1cipher)) != 0 ||
2402: (r = sshbuf_put_string(m, state->ssh1_key, state->ssh1_keylen)) != 0 ||
2403: (r = sshbuf_put_u32(m, slen)) != 0 ||
2404: (r = sshbuf_reserve(m, slen, &p)) != 0 ||
2405: (r = cipher_get_keyiv(&state->send_context, p, slen)) != 0 ||
2406: (r = sshbuf_put_u32(m, rlen)) != 0 ||
2407: (r = sshbuf_reserve(m, rlen, &p)) != 0 ||
2408: (r = cipher_get_keyiv(&state->receive_context, p, rlen)) != 0)
2409: return r;
2410: } else {
2411: if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2412: (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2413: (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
1.208 markus 2414: (r = sshbuf_put_u32(m, state->rekey_limit)) != 0 ||
2415: (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
1.201 markus 2416: (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2417: (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2418: (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2419: (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2420: (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2421: (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2422: (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2423: (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0)
2424: return r;
2425: }
2426:
2427: slen = cipher_get_keycontext(&state->send_context, NULL);
2428: rlen = cipher_get_keycontext(&state->receive_context, NULL);
2429: if ((r = sshbuf_put_u32(m, slen)) != 0 ||
2430: (r = sshbuf_reserve(m, slen, &p)) != 0)
2431: return r;
2432: if (cipher_get_keycontext(&state->send_context, p) != (int)slen)
2433: return SSH_ERR_INTERNAL_ERROR;
2434: if ((r = sshbuf_put_u32(m, rlen)) != 0 ||
2435: (r = sshbuf_reserve(m, rlen, &p)) != 0)
2436: return r;
2437: if (cipher_get_keycontext(&state->receive_context, p) != (int)rlen)
2438: return SSH_ERR_INTERNAL_ERROR;
2439:
2440: if ((r = ssh_packet_get_compress_state(m, ssh)) != 0 ||
2441: (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2442: (r = sshbuf_put_stringb(m, state->output)) != 0)
2443: return r;
2444:
2445: return 0;
2446: }
2447:
2448: /* restore key exchange results from blob for packet state de-serialization */
2449: static int
2450: newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2451: {
2452: struct sshbuf *b = NULL;
2453: struct sshcomp *comp;
2454: struct sshenc *enc;
2455: struct sshmac *mac;
2456: struct newkeys *newkey = NULL;
2457: size_t keylen, ivlen, maclen;
2458: int r;
2459:
2460: if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2461: r = SSH_ERR_ALLOC_FAIL;
2462: goto out;
2463: }
2464: if ((r = sshbuf_froms(m, &b)) != 0)
2465: goto out;
2466: #ifdef DEBUG_PK
2467: sshbuf_dump(b, stderr);
2468: #endif
2469: enc = &newkey->enc;
2470: mac = &newkey->mac;
2471: comp = &newkey->comp;
2472:
2473: if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2474: (r = sshbuf_get(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2475: (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2476: (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2477: (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2478: (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2479: goto out;
2480: if (cipher_authlen(enc->cipher) == 0) {
2481: if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2482: goto out;
2483: if ((r = mac_setup(mac, mac->name)) != 0)
2484: goto out;
2485: if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2486: (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2487: goto out;
2488: if (maclen > mac->key_len) {
2489: r = SSH_ERR_INVALID_FORMAT;
2490: goto out;
2491: }
2492: mac->key_len = maclen;
2493: }
2494: if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2495: (r = sshbuf_get_u32(b, (u_int *)&comp->enabled)) != 0 ||
2496: (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2497: goto out;
2498: if (enc->name == NULL ||
2499: cipher_by_name(enc->name) != enc->cipher) {
2500: r = SSH_ERR_INVALID_FORMAT;
2501: goto out;
2502: }
2503: if (sshbuf_len(b) != 0) {
2504: r = SSH_ERR_INVALID_FORMAT;
2505: goto out;
2506: }
2507: enc->key_len = keylen;
2508: enc->iv_len = ivlen;
2509: ssh->kex->newkeys[mode] = newkey;
2510: newkey = NULL;
2511: r = 0;
2512: out:
1.219 mmcc 2513: free(newkey);
1.221 mmcc 2514: sshbuf_free(b);
1.201 markus 2515: return r;
2516: }
2517:
2518: /* restore kex from blob for packet state de-serialization */
2519: static int
2520: kex_from_blob(struct sshbuf *m, struct kex **kexp)
2521: {
2522: struct kex *kex;
2523: int r;
2524:
2525: if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2526: (kex->my = sshbuf_new()) == NULL ||
2527: (kex->peer = sshbuf_new()) == NULL) {
2528: r = SSH_ERR_ALLOC_FAIL;
2529: goto out;
2530: }
2531: if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2532: (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2533: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2534: (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2535: (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2536: (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2537: (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2538: (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2539: (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2540: goto out;
2541: kex->server = 1;
2542: kex->done = 1;
2543: r = 0;
2544: out:
2545: if (r != 0 || kexp == NULL) {
2546: if (kex != NULL) {
1.221 mmcc 2547: sshbuf_free(kex->my);
2548: sshbuf_free(kex->peer);
1.201 markus 2549: free(kex);
2550: }
2551: if (kexp != NULL)
2552: *kexp = NULL;
2553: } else {
2554: *kexp = kex;
2555: }
2556: return r;
2557: }
2558:
2559: /*
2560: * Restore packet state from content of blob 'm' (de-serialization).
2561: * Note that 'm' will be partially consumed on parsing or any other errors.
2562: */
2563: int
2564: ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2565: {
2566: struct session_state *state = ssh->state;
2567: const u_char *ssh1key, *ivin, *ivout, *keyin, *keyout, *input, *output;
2568: size_t ssh1keylen, rlen, slen, ilen, olen;
2569: int r;
2570: u_int ssh1cipher = 0;
2571:
2572: if (!compat20) {
2573: if ((r = sshbuf_get_u32(m, &state->remote_protocol_flags)) != 0 ||
2574: (r = sshbuf_get_u32(m, &ssh1cipher)) != 0 ||
2575: (r = sshbuf_get_string_direct(m, &ssh1key, &ssh1keylen)) != 0 ||
2576: (r = sshbuf_get_string_direct(m, &ivout, &slen)) != 0 ||
2577: (r = sshbuf_get_string_direct(m, &ivin, &rlen)) != 0)
2578: return r;
2579: if (ssh1cipher > INT_MAX)
2580: return SSH_ERR_KEY_UNKNOWN_CIPHER;
2581: ssh_packet_set_encryption_key(ssh, ssh1key, ssh1keylen,
2582: (int)ssh1cipher);
2583: if (cipher_get_keyiv_len(&state->send_context) != (int)slen ||
2584: cipher_get_keyiv_len(&state->receive_context) != (int)rlen)
2585: return SSH_ERR_INVALID_FORMAT;
2586: if ((r = cipher_set_keyiv(&state->send_context, ivout)) != 0 ||
2587: (r = cipher_set_keyiv(&state->receive_context, ivin)) != 0)
2588: return r;
2589: } else {
2590: if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2591: (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2592: (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
1.208 markus 2593: (r = sshbuf_get_u32(m, &state->rekey_limit)) != 0 ||
2594: (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
1.201 markus 2595: (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2596: (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2597: (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2598: (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2599: (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2600: (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2601: (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2602: (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2603: return r;
1.208 markus 2604: /*
2605: * We set the time here so that in post-auth privsep slave we
2606: * count from the completion of the authentication.
2607: */
2608: state->rekey_time = monotime();
1.201 markus 2609: /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2610: if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2611: (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2612: return r;
2613: }
2614: if ((r = sshbuf_get_string_direct(m, &keyout, &slen)) != 0 ||
2615: (r = sshbuf_get_string_direct(m, &keyin, &rlen)) != 0)
2616: return r;
2617: if (cipher_get_keycontext(&state->send_context, NULL) != (int)slen ||
2618: cipher_get_keycontext(&state->receive_context, NULL) != (int)rlen)
2619: return SSH_ERR_INVALID_FORMAT;
2620: cipher_set_keycontext(&state->send_context, keyout);
2621: cipher_set_keycontext(&state->receive_context, keyin);
2622:
2623: if ((r = ssh_packet_set_compress_state(ssh, m)) != 0 ||
2624: (r = ssh_packet_set_postauth(ssh)) != 0)
2625: return r;
2626:
2627: sshbuf_reset(state->input);
2628: sshbuf_reset(state->output);
2629: if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2630: (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2631: (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2632: (r = sshbuf_put(state->output, output, olen)) != 0)
2633: return r;
2634:
2635: if (sshbuf_len(m))
2636: return SSH_ERR_INVALID_FORMAT;
2637: debug3("%s: done", __func__);
2638: return 0;
2639: }
2640:
2641: /* NEW API */
2642:
2643: /* put data to the outgoing packet */
2644:
2645: int
2646: sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2647: {
2648: return sshbuf_put(ssh->state->outgoing_packet, v, len);
2649: }
2650:
2651: int
2652: sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2653: {
2654: return sshbuf_putb(ssh->state->outgoing_packet, b);
2655: }
2656:
2657: int
2658: sshpkt_put_u8(struct ssh *ssh, u_char val)
2659: {
2660: return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2661: }
2662:
2663: int
2664: sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2665: {
2666: return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2667: }
2668:
2669: int
2670: sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2671: {
2672: return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2673: }
2674:
2675: int
2676: sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2677: {
2678: return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2679: }
2680:
2681: int
2682: sshpkt_put_cstring(struct ssh *ssh, const void *v)
2683: {
2684: return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2685: }
2686:
2687: int
2688: sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2689: {
2690: return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2691: }
2692:
1.211 djm 2693: #ifdef WITH_OPENSSL
1.201 markus 2694: int
2695: sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2696: {
2697: return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2698: }
2699:
1.211 djm 2700: #ifdef WITH_SSH1
1.201 markus 2701: int
2702: sshpkt_put_bignum1(struct ssh *ssh, const BIGNUM *v)
2703: {
2704: return sshbuf_put_bignum1(ssh->state->outgoing_packet, v);
2705: }
1.211 djm 2706: #endif /* WITH_SSH1 */
1.201 markus 2707:
2708: int
2709: sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2710: {
2711: return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2712: }
1.211 djm 2713: #endif /* WITH_OPENSSL */
1.201 markus 2714:
2715: /* fetch data from the incoming packet */
2716:
2717: int
2718: sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2719: {
2720: return sshbuf_get(ssh->state->incoming_packet, valp, len);
2721: }
2722:
2723: int
2724: sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2725: {
2726: return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2727: }
2728:
2729: int
2730: sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2731: {
2732: return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2733: }
2734:
2735: int
2736: sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2737: {
2738: return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2739: }
2740:
2741: int
2742: sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2743: {
2744: return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2745: }
2746:
2747: int
2748: sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2749: {
2750: return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2751: }
2752:
2753: int
2754: sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2755: {
2756: return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2757: }
2758:
1.211 djm 2759: #ifdef WITH_OPENSSL
1.201 markus 2760: int
2761: sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2762: {
2763: return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2764: }
2765:
1.211 djm 2766: #ifdef WITH_SSH1
1.201 markus 2767: int
2768: sshpkt_get_bignum1(struct ssh *ssh, BIGNUM *v)
2769: {
2770: return sshbuf_get_bignum1(ssh->state->incoming_packet, v);
2771: }
1.211 djm 2772: #endif /* WITH_SSH1 */
1.201 markus 2773:
2774: int
2775: sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2776: {
2777: return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2778: }
1.211 djm 2779: #endif /* WITH_OPENSSL */
1.201 markus 2780:
2781: int
2782: sshpkt_get_end(struct ssh *ssh)
2783: {
2784: if (sshbuf_len(ssh->state->incoming_packet) > 0)
2785: return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2786: return 0;
2787: }
2788:
2789: const u_char *
2790: sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2791: {
2792: if (lenp != NULL)
2793: *lenp = sshbuf_len(ssh->state->incoming_packet);
2794: return sshbuf_ptr(ssh->state->incoming_packet);
2795: }
2796:
2797: /* start a new packet */
2798:
2799: int
2800: sshpkt_start(struct ssh *ssh, u_char type)
2801: {
2802: u_char buf[9];
2803: int len;
2804:
2805: DBG(debug("packet_start[%d]", type));
2806: len = compat20 ? 6 : 9;
2807: memset(buf, 0, len - 1);
2808: buf[len - 1] = type;
2809: sshbuf_reset(ssh->state->outgoing_packet);
2810: return sshbuf_put(ssh->state->outgoing_packet, buf, len);
2811: }
2812:
2813: /* send it */
2814:
2815: int
2816: sshpkt_send(struct ssh *ssh)
2817: {
2818: if (compat20)
2819: return ssh_packet_send2(ssh);
2820: else
2821: return ssh_packet_send1(ssh);
2822: }
2823:
2824: int
2825: sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2826: {
2827: char buf[1024];
2828: va_list args;
2829: int r;
2830:
2831: va_start(args, fmt);
2832: vsnprintf(buf, sizeof(buf), fmt, args);
2833: va_end(args);
2834:
2835: if (compat20) {
2836: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2837: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2838: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2839: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2840: (r = sshpkt_send(ssh)) != 0)
2841: return r;
2842: } else {
2843: if ((r = sshpkt_start(ssh, SSH_MSG_DISCONNECT)) != 0 ||
2844: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2845: (r = sshpkt_send(ssh)) != 0)
2846: return r;
1.166 andreas 2847: }
1.201 markus 2848: return 0;
2849: }
2850:
2851: /* roundup current message to pad bytes */
2852: int
2853: sshpkt_add_padding(struct ssh *ssh, u_char pad)
2854: {
2855: ssh->state->extra_pad = pad;
2856: return 0;
1.1 deraadt 2857: }
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