Annotation of src/usr.bin/ssh/packet.c, Revision 1.227
1.227 ! djm 1: /* $OpenBSD: packet.c,v 1.226 2016/01/29 05:46:01 djm Exp $ */
1.1 deraadt 2: /*
1.15 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.35 deraadt 6: * This file contains code implementing the packet protocol and communication
7: * with the other side. This same code is used both on client and server side.
1.29 markus 8: *
1.35 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
1.29 markus 14: *
1.25 markus 15: *
16: * SSH2 packet format added by Markus Friedl.
1.69 markus 17: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.25 markus 18: *
1.35 deraadt 19: * Redistribution and use in source and binary forms, with or without
20: * modification, are permitted provided that the following conditions
21: * are met:
22: * 1. Redistributions of source code must retain the above copyright
23: * notice, this list of conditions and the following disclaimer.
24: * 2. Redistributions in binary form must reproduce the above copyright
25: * notice, this list of conditions and the following disclaimer in the
26: * documentation and/or other materials provided with the distribution.
27: *
28: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
29: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
30: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
31: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
32: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
33: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
37: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.15 deraadt 38: */
1.1 deraadt 39:
1.203 deraadt 40: #include <sys/param.h> /* MIN roundup */
1.142 deraadt 41: #include <sys/types.h>
1.105 markus 42: #include <sys/queue.h>
1.132 stevesk 43: #include <sys/socket.h>
1.138 stevesk 44: #include <sys/time.h>
1.132 stevesk 45: #include <netinet/in.h>
1.121 stevesk 46: #include <netinet/ip.h>
1.134 stevesk 47:
1.135 stevesk 48: #include <errno.h>
1.134 stevesk 49: #include <stdarg.h>
1.141 stevesk 50: #include <stdio.h>
1.140 stevesk 51: #include <stdlib.h>
1.137 stevesk 52: #include <string.h>
1.136 stevesk 53: #include <unistd.h>
1.203 deraadt 54: #include <limits.h>
1.142 deraadt 55: #include <signal.h>
1.184 dtucker 56: #include <time.h>
1.1 deraadt 57:
1.201 markus 58: #include <zlib.h>
59:
60: #include "buffer.h" /* typedefs XXX */
61: #include "key.h" /* typedefs XXX */
62:
1.1 deraadt 63: #include "xmalloc.h"
64: #include "crc32.h"
1.9 dugsong 65: #include "deattack.h"
1.25 markus 66: #include "compat.h"
1.45 markus 67: #include "ssh1.h"
1.25 markus 68: #include "ssh2.h"
1.37 markus 69: #include "cipher.h"
1.201 markus 70: #include "sshkey.h"
1.25 markus 71: #include "kex.h"
1.200 markus 72: #include "digest.h"
1.50 markus 73: #include "mac.h"
1.46 markus 74: #include "log.h"
75: #include "canohost.h"
1.87 stevesk 76: #include "misc.h"
1.198 millert 77: #include "channels.h"
1.95 markus 78: #include "ssh.h"
1.201 markus 79: #include "packet.h"
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 */
1.224 dtucker 177: u_int64_t max_blocks_in, max_blocks_out, rekey_limit;
1.105 markus 178:
1.184 dtucker 179: /* Time-based rekeying */
1.208 markus 180: u_int32_t rekey_interval; /* how often in seconds */
1.184 dtucker 181: time_t rekey_time; /* time of last rekeying */
182:
1.161 andreas 183: /* Session key for protocol v1 */
184: u_char ssh1_key[SSH_SESSION_KEY_LENGTH];
185: u_int ssh1_keylen;
1.25 markus 186:
1.161 andreas 187: /* roundup current message to extra_pad bytes */
188: u_char extra_pad;
1.95 markus 189:
1.161 andreas 190: /* XXX discard incoming data after MAC error */
191: u_int packet_discard;
1.201 markus 192: struct sshmac *packet_discard_mac;
1.71 markus 193:
1.161 andreas 194: /* Used in packet_read_poll2() */
195: u_int packlen;
1.159 markus 196:
1.165 andreas 197: /* Used in packet_send2 */
198: int rekeying;
199:
200: /* Used in packet_set_interactive */
201: int set_interactive_called;
202:
203: /* Used in packet_set_maxsize */
204: int set_maxsize_called;
205:
1.201 markus 206: /* One-off warning about weak ciphers */
207: int cipher_warning_done;
208:
209: /* SSH1 CRC compensation attack detector */
210: struct deattack_ctx deattack;
211:
1.161 andreas 212: TAILQ_HEAD(, packet) outgoing;
1.105 markus 213: };
1.161 andreas 214:
1.201 markus 215: struct ssh *
216: ssh_alloc_session_state(void)
1.161 andreas 217: {
1.201 markus 218: struct ssh *ssh = NULL;
219: struct session_state *state = NULL;
1.161 andreas 220:
1.201 markus 221: if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
222: (state = calloc(1, sizeof(*state))) == NULL ||
223: (state->input = sshbuf_new()) == NULL ||
224: (state->output = sshbuf_new()) == NULL ||
225: (state->outgoing_packet = sshbuf_new()) == NULL ||
226: (state->incoming_packet = sshbuf_new()) == NULL)
227: goto fail;
228: TAILQ_INIT(&state->outgoing);
1.202 markus 229: TAILQ_INIT(&ssh->private_keys);
230: TAILQ_INIT(&ssh->public_keys);
1.201 markus 231: state->connection_in = -1;
232: state->connection_out = -1;
233: state->max_packet_size = 32768;
234: state->packet_timeout_ms = -1;
235: state->p_send.packets = state->p_read.packets = 0;
236: state->initialized = 1;
237: /*
238: * ssh_packet_send2() needs to queue packets until
239: * we've done the initial key exchange.
240: */
241: state->rekeying = 1;
242: ssh->state = state;
243: return ssh;
244: fail:
245: if (state) {
246: sshbuf_free(state->input);
247: sshbuf_free(state->output);
248: sshbuf_free(state->incoming_packet);
249: sshbuf_free(state->outgoing_packet);
250: free(state);
251: }
252: free(ssh);
253: return NULL;
1.161 andreas 254: }
1.105 markus 255:
1.16 markus 256: /*
257: * Sets the descriptors used for communication. Disables encryption until
258: * packet_set_encryption_key is called.
259: */
1.201 markus 260: struct ssh *
261: ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
1.1 deraadt 262: {
1.201 markus 263: struct session_state *state;
264: const struct sshcipher *none = cipher_by_name("none");
1.197 djm 265: int r;
1.97 deraadt 266:
1.205 djm 267: if (none == NULL) {
268: error("%s: cannot load cipher 'none'", __func__);
269: return NULL;
270: }
1.201 markus 271: if (ssh == NULL)
272: ssh = ssh_alloc_session_state();
1.205 djm 273: if (ssh == NULL) {
274: error("%s: cound not allocate state", __func__);
275: return NULL;
276: }
1.201 markus 277: state = ssh->state;
278: state->connection_in = fd_in;
279: state->connection_out = fd_out;
280: if ((r = cipher_init(&state->send_context, none,
1.197 djm 281: (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
1.201 markus 282: (r = cipher_init(&state->receive_context, none,
1.205 djm 283: (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
284: error("%s: cipher_init failed: %s", __func__, ssh_err(r));
1.209 jsg 285: free(ssh);
1.205 djm 286: return NULL;
287: }
1.201 markus 288: state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
289: deattack_init(&state->deattack);
1.207 djm 290: /*
291: * Cache the IP address of the remote connection for use in error
292: * messages that might be generated after the connection has closed.
293: */
294: (void)ssh_remote_ipaddr(ssh);
1.201 markus 295: return ssh;
1.1 deraadt 296: }
297:
1.154 dtucker 298: void
1.201 markus 299: ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
1.154 dtucker 300: {
1.201 markus 301: struct session_state *state = ssh->state;
302:
1.174 djm 303: if (timeout <= 0 || count <= 0) {
1.201 markus 304: state->packet_timeout_ms = -1;
1.154 dtucker 305: return;
306: }
307: if ((INT_MAX / 1000) / count < timeout)
1.201 markus 308: state->packet_timeout_ms = INT_MAX;
1.154 dtucker 309: else
1.201 markus 310: state->packet_timeout_ms = timeout * count * 1000;
1.154 dtucker 311: }
312:
1.201 markus 313: int
314: ssh_packet_stop_discard(struct ssh *ssh)
1.159 markus 315: {
1.201 markus 316: struct session_state *state = ssh->state;
317: int r;
318:
319: if (state->packet_discard_mac) {
1.159 markus 320: char buf[1024];
1.201 markus 321:
1.159 markus 322: memset(buf, 'a', sizeof(buf));
1.201 markus 323: while (sshbuf_len(state->incoming_packet) <
1.161 andreas 324: PACKET_MAX_SIZE)
1.201 markus 325: if ((r = sshbuf_put(state->incoming_packet, buf,
326: sizeof(buf))) != 0)
327: return r;
328: (void) mac_compute(state->packet_discard_mac,
329: state->p_read.seqnr,
330: sshbuf_ptr(state->incoming_packet), PACKET_MAX_SIZE,
331: NULL, 0);
1.159 markus 332: }
1.220 djm 333: logit("Finished discarding for %.200s port %d",
334: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.201 markus 335: return SSH_ERR_MAC_INVALID;
1.159 markus 336: }
337:
1.201 markus 338: static int
339: ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
340: struct sshmac *mac, u_int packet_length, u_int discard)
1.159 markus 341: {
1.201 markus 342: struct session_state *state = ssh->state;
343: int r;
344:
345: if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
346: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
347: return r;
348: return SSH_ERR_MAC_INVALID;
349: }
1.159 markus 350: if (packet_length != PACKET_MAX_SIZE && mac && mac->enabled)
1.201 markus 351: state->packet_discard_mac = mac;
352: if (sshbuf_len(state->input) >= discard &&
353: (r = ssh_packet_stop_discard(ssh)) != 0)
354: return r;
355: state->packet_discard = discard - sshbuf_len(state->input);
356: return 0;
1.159 markus 357: }
358:
1.19 markus 359: /* Returns 1 if remote host is connected via socket, 0 if not. */
360:
361: int
1.201 markus 362: ssh_packet_connection_is_on_socket(struct ssh *ssh)
1.19 markus 363: {
1.201 markus 364: struct session_state *state = ssh->state;
1.19 markus 365: struct sockaddr_storage from, to;
366: socklen_t fromlen, tolen;
367:
368: /* filedescriptors in and out are the same, so it's a socket */
1.201 markus 369: if (state->connection_in == state->connection_out)
1.19 markus 370: return 1;
371: fromlen = sizeof(from);
372: memset(&from, 0, sizeof(from));
1.201 markus 373: if (getpeername(state->connection_in, (struct sockaddr *)&from,
1.161 andreas 374: &fromlen) < 0)
1.19 markus 375: return 0;
376: tolen = sizeof(to);
377: memset(&to, 0, sizeof(to));
1.201 markus 378: if (getpeername(state->connection_out, (struct sockaddr *)&to,
1.161 andreas 379: &tolen) < 0)
1.19 markus 380: return 0;
381: if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
382: return 0;
383: if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
384: return 0;
385: return 1;
386: }
387:
1.91 markus 388: void
1.201 markus 389: ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
1.91 markus 390: {
1.201 markus 391: if (ibytes)
392: *ibytes = ssh->state->p_read.bytes;
393: if (obytes)
394: *obytes = ssh->state->p_send.bytes;
1.91 markus 395: }
1.125 deraadt 396:
1.91 markus 397: int
1.201 markus 398: ssh_packet_connection_af(struct ssh *ssh)
1.19 markus 399: {
400: struct sockaddr_storage to;
1.21 deraadt 401: socklen_t tolen = sizeof(to);
1.19 markus 402:
403: memset(&to, 0, sizeof(to));
1.201 markus 404: if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
1.161 andreas 405: &tolen) < 0)
1.19 markus 406: return 0;
1.173 djm 407: return to.ss_family;
1.19 markus 408: }
409:
1.1 deraadt 410: /* Sets the connection into non-blocking mode. */
411:
1.2 provos 412: void
1.201 markus 413: ssh_packet_set_nonblocking(struct ssh *ssh)
1.1 deraadt 414: {
1.14 markus 415: /* Set the socket into non-blocking mode. */
1.201 markus 416: set_nonblock(ssh->state->connection_in);
1.14 markus 417:
1.201 markus 418: if (ssh->state->connection_out != ssh->state->connection_in)
419: set_nonblock(ssh->state->connection_out);
1.1 deraadt 420: }
421:
422: /* Returns the socket used for reading. */
423:
1.2 provos 424: int
1.201 markus 425: ssh_packet_get_connection_in(struct ssh *ssh)
1.1 deraadt 426: {
1.201 markus 427: return ssh->state->connection_in;
1.1 deraadt 428: }
429:
430: /* Returns the descriptor used for writing. */
431:
1.2 provos 432: int
1.201 markus 433: ssh_packet_get_connection_out(struct ssh *ssh)
1.1 deraadt 434: {
1.201 markus 435: return ssh->state->connection_out;
436: }
437:
438: /*
439: * Returns the IP-address of the remote host as a string. The returned
440: * string must not be freed.
441: */
442:
443: const char *
444: ssh_remote_ipaddr(struct ssh *ssh)
445: {
1.220 djm 446: const int sock = ssh->state->connection_in;
447:
1.201 markus 448: /* Check whether we have cached the ipaddr. */
1.220 djm 449: if (ssh->remote_ipaddr == NULL) {
450: if (ssh_packet_connection_is_on_socket(ssh)) {
451: ssh->remote_ipaddr = get_peer_ipaddr(sock);
452: ssh->remote_port = get_sock_port(sock, 0);
453: } else {
454: ssh->remote_ipaddr = strdup("UNKNOWN");
455: ssh->remote_port = 0;
456: }
457: }
1.201 markus 458: return ssh->remote_ipaddr;
1.1 deraadt 459: }
460:
1.220 djm 461: /* Returns the port number of the remote host. */
462:
463: int
464: ssh_remote_port(struct ssh *ssh)
465: {
466: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
467: return ssh->remote_port;
468: }
469:
1.1 deraadt 470: /* Closes the connection and clears and frees internal data structures. */
471:
1.2 provos 472: void
1.201 markus 473: ssh_packet_close(struct ssh *ssh)
1.1 deraadt 474: {
1.201 markus 475: struct session_state *state = ssh->state;
476: int r;
477: u_int mode;
478:
479: if (!state->initialized)
1.14 markus 480: return;
1.201 markus 481: state->initialized = 0;
482: if (state->connection_in == state->connection_out) {
483: shutdown(state->connection_out, SHUT_RDWR);
484: close(state->connection_out);
1.14 markus 485: } else {
1.201 markus 486: close(state->connection_in);
487: close(state->connection_out);
1.14 markus 488: }
1.201 markus 489: sshbuf_free(state->input);
490: sshbuf_free(state->output);
491: sshbuf_free(state->outgoing_packet);
492: sshbuf_free(state->incoming_packet);
493: for (mode = 0; mode < MODE_MAX; mode++)
494: kex_free_newkeys(state->newkeys[mode]);
495: if (state->compression_buffer) {
496: sshbuf_free(state->compression_buffer);
497: if (state->compression_out_started) {
498: z_streamp stream = &state->compression_out_stream;
499: debug("compress outgoing: "
500: "raw data %llu, compressed %llu, factor %.2f",
501: (unsigned long long)stream->total_in,
502: (unsigned long long)stream->total_out,
503: stream->total_in == 0 ? 0.0 :
504: (double) stream->total_out / stream->total_in);
505: if (state->compression_out_failures == 0)
506: deflateEnd(stream);
507: }
508: if (state->compression_in_started) {
509: z_streamp stream = &state->compression_out_stream;
510: debug("compress incoming: "
511: "raw data %llu, compressed %llu, factor %.2f",
512: (unsigned long long)stream->total_out,
513: (unsigned long long)stream->total_in,
514: stream->total_out == 0 ? 0.0 :
515: (double) stream->total_in / stream->total_out);
516: if (state->compression_in_failures == 0)
517: inflateEnd(stream);
518: }
1.14 markus 519: }
1.201 markus 520: if ((r = cipher_cleanup(&state->send_context)) != 0)
521: error("%s: cipher_cleanup failed: %s", __func__, ssh_err(r));
522: if ((r = cipher_cleanup(&state->receive_context)) != 0)
523: error("%s: cipher_cleanup failed: %s", __func__, ssh_err(r));
1.219 mmcc 524: free(ssh->remote_ipaddr);
525: ssh->remote_ipaddr = NULL;
1.201 markus 526: free(ssh->state);
527: ssh->state = NULL;
1.1 deraadt 528: }
529:
530: /* Sets remote side protocol flags. */
531:
1.2 provos 532: void
1.201 markus 533: ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
1.1 deraadt 534: {
1.201 markus 535: ssh->state->remote_protocol_flags = protocol_flags;
1.1 deraadt 536: }
537:
538: /* Returns the remote protocol flags set earlier by the above function. */
539:
1.40 markus 540: u_int
1.201 markus 541: ssh_packet_get_protocol_flags(struct ssh *ssh)
1.1 deraadt 542: {
1.201 markus 543: return ssh->state->remote_protocol_flags;
1.1 deraadt 544: }
545:
1.16 markus 546: /*
547: * Starts packet compression from the next packet on in both directions.
548: * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
549: */
1.1 deraadt 550:
1.201 markus 551: static int
552: ssh_packet_init_compression(struct ssh *ssh)
1.60 markus 553: {
1.201 markus 554: if (!ssh->state->compression_buffer &&
555: ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
556: return SSH_ERR_ALLOC_FAIL;
557: return 0;
1.60 markus 558: }
559:
1.201 markus 560: static int
561: start_compression_out(struct ssh *ssh, int level)
1.1 deraadt 562: {
1.201 markus 563: if (level < 1 || level > 9)
564: return SSH_ERR_INVALID_ARGUMENT;
565: debug("Enabling compression at level %d.", level);
566: if (ssh->state->compression_out_started == 1)
567: deflateEnd(&ssh->state->compression_out_stream);
568: switch (deflateInit(&ssh->state->compression_out_stream, level)) {
569: case Z_OK:
570: ssh->state->compression_out_started = 1;
571: break;
572: case Z_MEM_ERROR:
573: return SSH_ERR_ALLOC_FAIL;
574: default:
575: return SSH_ERR_INTERNAL_ERROR;
576: }
577: return 0;
1.1 deraadt 578: }
579:
1.201 markus 580: static int
581: start_compression_in(struct ssh *ssh)
582: {
583: if (ssh->state->compression_in_started == 1)
584: inflateEnd(&ssh->state->compression_in_stream);
585: switch (inflateInit(&ssh->state->compression_in_stream)) {
586: case Z_OK:
587: ssh->state->compression_in_started = 1;
588: break;
589: case Z_MEM_ERROR:
590: return SSH_ERR_ALLOC_FAIL;
591: default:
592: return SSH_ERR_INTERNAL_ERROR;
593: }
594: return 0;
595: }
1.95 markus 596:
1.201 markus 597: int
598: ssh_packet_start_compression(struct ssh *ssh, int level)
1.1 deraadt 599: {
1.197 djm 600: int r;
1.97 deraadt 601:
1.201 markus 602: if (ssh->state->packet_compression && !compat20)
603: return SSH_ERR_INTERNAL_ERROR;
604: ssh->state->packet_compression = 1;
605: if ((r = ssh_packet_init_compression(ssh)) != 0 ||
606: (r = start_compression_in(ssh)) != 0 ||
607: (r = start_compression_out(ssh, level)) != 0)
608: return r;
609: return 0;
1.95 markus 610: }
611:
1.201 markus 612: /* XXX remove need for separate compression buffer */
613: static int
614: compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.95 markus 615: {
1.201 markus 616: u_char buf[4096];
617: int r, status;
618:
619: if (ssh->state->compression_out_started != 1)
620: return SSH_ERR_INTERNAL_ERROR;
621:
622: /* This case is not handled below. */
623: if (sshbuf_len(in) == 0)
624: return 0;
625:
626: /* Input is the contents of the input buffer. */
627: if ((ssh->state->compression_out_stream.next_in =
628: sshbuf_mutable_ptr(in)) == NULL)
629: return SSH_ERR_INTERNAL_ERROR;
630: ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
631:
632: /* Loop compressing until deflate() returns with avail_out != 0. */
633: do {
634: /* Set up fixed-size output buffer. */
635: ssh->state->compression_out_stream.next_out = buf;
636: ssh->state->compression_out_stream.avail_out = sizeof(buf);
637:
638: /* Compress as much data into the buffer as possible. */
639: status = deflate(&ssh->state->compression_out_stream,
640: Z_PARTIAL_FLUSH);
641: switch (status) {
642: case Z_MEM_ERROR:
643: return SSH_ERR_ALLOC_FAIL;
644: case Z_OK:
645: /* Append compressed data to output_buffer. */
646: if ((r = sshbuf_put(out, buf, sizeof(buf) -
647: ssh->state->compression_out_stream.avail_out)) != 0)
648: return r;
649: break;
650: case Z_STREAM_ERROR:
651: default:
652: ssh->state->compression_out_failures++;
653: return SSH_ERR_INVALID_FORMAT;
654: }
655: } while (ssh->state->compression_out_stream.avail_out == 0);
656: return 0;
1.1 deraadt 657: }
658:
1.201 markus 659: static int
660: uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.1 deraadt 661: {
1.201 markus 662: u_char buf[4096];
663: int r, status;
1.1 deraadt 664:
1.201 markus 665: if (ssh->state->compression_in_started != 1)
666: return SSH_ERR_INTERNAL_ERROR;
1.25 markus 667:
1.201 markus 668: if ((ssh->state->compression_in_stream.next_in =
669: sshbuf_mutable_ptr(in)) == NULL)
670: return SSH_ERR_INTERNAL_ERROR;
671: ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
1.97 deraadt 672:
1.201 markus 673: for (;;) {
674: /* Set up fixed-size output buffer. */
675: ssh->state->compression_in_stream.next_out = buf;
676: ssh->state->compression_in_stream.avail_out = sizeof(buf);
677:
678: status = inflate(&ssh->state->compression_in_stream,
679: Z_PARTIAL_FLUSH);
680: switch (status) {
681: case Z_OK:
682: if ((r = sshbuf_put(out, buf, sizeof(buf) -
683: ssh->state->compression_in_stream.avail_out)) != 0)
684: return r;
685: break;
686: case Z_BUF_ERROR:
687: /*
688: * Comments in zlib.h say that we should keep calling
689: * inflate() until we get an error. This appears to
690: * be the error that we get.
691: */
692: return 0;
693: case Z_DATA_ERROR:
694: return SSH_ERR_INVALID_FORMAT;
695: case Z_MEM_ERROR:
696: return SSH_ERR_ALLOC_FAIL;
697: case Z_STREAM_ERROR:
698: default:
699: ssh->state->compression_in_failures++;
700: return SSH_ERR_INTERNAL_ERROR;
701: }
702: }
703: /* NOTREACHED */
1.1 deraadt 704: }
1.125 deraadt 705:
1.201 markus 706: /* Serialise compression state into a blob for privsep */
707: static int
708: ssh_packet_get_compress_state(struct sshbuf *m, struct ssh *ssh)
1.1 deraadt 709: {
1.201 markus 710: struct session_state *state = ssh->state;
711: struct sshbuf *b;
712: int r;
713:
714: if ((b = sshbuf_new()) == NULL)
715: return SSH_ERR_ALLOC_FAIL;
716: if (state->compression_in_started) {
717: if ((r = sshbuf_put_string(b, &state->compression_in_stream,
718: sizeof(state->compression_in_stream))) != 0)
719: goto out;
720: } else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
721: goto out;
722: if (state->compression_out_started) {
723: if ((r = sshbuf_put_string(b, &state->compression_out_stream,
724: sizeof(state->compression_out_stream))) != 0)
725: goto out;
726: } else if ((r = sshbuf_put_string(b, NULL, 0)) != 0)
727: goto out;
728: r = sshbuf_put_stringb(m, b);
729: out:
730: sshbuf_free(b);
731: return r;
1.1 deraadt 732: }
1.125 deraadt 733:
1.201 markus 734: /* Deserialise compression state from a blob for privsep */
735: static int
736: ssh_packet_set_compress_state(struct ssh *ssh, struct sshbuf *m)
1.162 andreas 737: {
1.201 markus 738: struct session_state *state = ssh->state;
739: struct sshbuf *b = NULL;
740: int r;
741: const u_char *inblob, *outblob;
742: size_t inl, outl;
1.162 andreas 743:
1.201 markus 744: if ((r = sshbuf_froms(m, &b)) != 0)
745: goto out;
746: if ((r = sshbuf_get_string_direct(b, &inblob, &inl)) != 0 ||
747: (r = sshbuf_get_string_direct(b, &outblob, &outl)) != 0)
748: goto out;
749: if (inl == 0)
750: state->compression_in_started = 0;
751: else if (inl != sizeof(state->compression_in_stream)) {
752: r = SSH_ERR_INTERNAL_ERROR;
753: goto out;
754: } else {
755: state->compression_in_started = 1;
756: memcpy(&state->compression_in_stream, inblob, inl);
757: }
758: if (outl == 0)
759: state->compression_out_started = 0;
760: else if (outl != sizeof(state->compression_out_stream)) {
761: r = SSH_ERR_INTERNAL_ERROR;
762: goto out;
763: } else {
764: state->compression_out_started = 1;
765: memcpy(&state->compression_out_stream, outblob, outl);
766: }
767: r = 0;
768: out:
769: sshbuf_free(b);
770: return r;
1.1 deraadt 771: }
1.125 deraadt 772:
1.24 markus 773: void
1.201 markus 774: ssh_packet_set_compress_hooks(struct ssh *ssh, void *ctx,
775: void *(*allocfunc)(void *, u_int, u_int),
776: void (*freefunc)(void *, void *))
777: {
778: ssh->state->compression_out_stream.zalloc = (alloc_func)allocfunc;
779: ssh->state->compression_out_stream.zfree = (free_func)freefunc;
780: ssh->state->compression_out_stream.opaque = ctx;
781: ssh->state->compression_in_stream.zalloc = (alloc_func)allocfunc;
782: ssh->state->compression_in_stream.zfree = (free_func)freefunc;
783: ssh->state->compression_in_stream.opaque = ctx;
1.24 markus 784: }
1.125 deraadt 785:
1.201 markus 786: /*
787: * Causes any further packets to be encrypted using the given key. The same
788: * key is used for both sending and reception. However, both directions are
789: * encrypted independently of each other.
790: */
1.125 deraadt 791:
1.2 provos 792: void
1.201 markus 793: ssh_packet_set_encryption_key(struct ssh *ssh, const u_char *key, u_int keylen, int number)
1.1 deraadt 794: {
1.211 djm 795: #ifndef WITH_SSH1
796: fatal("no SSH protocol 1 support");
797: #else /* WITH_SSH1 */
1.201 markus 798: struct session_state *state = ssh->state;
799: const struct sshcipher *cipher = cipher_by_number(number);
800: int r;
801: const char *wmsg;
1.125 deraadt 802:
1.201 markus 803: if (cipher == NULL)
804: fatal("%s: unknown cipher number %d", __func__, number);
805: if (keylen < 20)
806: fatal("%s: keylen too small: %d", __func__, keylen);
807: if (keylen > SSH_SESSION_KEY_LENGTH)
808: fatal("%s: keylen too big: %d", __func__, keylen);
809: memcpy(state->ssh1_key, key, keylen);
810: state->ssh1_keylen = keylen;
811: if ((r = cipher_init(&state->send_context, cipher, key, keylen,
812: NULL, 0, CIPHER_ENCRYPT)) != 0 ||
813: (r = cipher_init(&state->receive_context, cipher, key, keylen,
814: NULL, 0, CIPHER_DECRYPT) != 0))
815: fatal("%s: cipher_init failed: %s", __func__, ssh_err(r));
816: if (!state->cipher_warning_done &&
817: ((wmsg = cipher_warning_message(&state->send_context)) != NULL ||
818: (wmsg = cipher_warning_message(&state->send_context)) != NULL)) {
819: error("Warning: %s", wmsg);
820: state->cipher_warning_done = 1;
821: }
1.211 djm 822: #endif /* WITH_SSH1 */
1.170 djm 823: }
824:
1.16 markus 825: /*
826: * Finalizes and sends the packet. If the encryption key has been set,
827: * encrypts the packet before sending.
828: */
1.14 markus 829:
1.201 markus 830: int
831: ssh_packet_send1(struct ssh *ssh)
1.1 deraadt 832: {
1.201 markus 833: struct session_state *state = ssh->state;
1.89 markus 834: u_char buf[8], *cp;
1.201 markus 835: int r, padding, len;
1.40 markus 836: u_int checksum;
1.14 markus 837:
1.16 markus 838: /*
839: * If using packet compression, compress the payload of the outgoing
840: * packet.
841: */
1.201 markus 842: if (state->packet_compression) {
843: sshbuf_reset(state->compression_buffer);
1.14 markus 844: /* Skip padding. */
1.201 markus 845: if ((r = sshbuf_consume(state->outgoing_packet, 8)) != 0)
846: goto out;
1.14 markus 847: /* padding */
1.201 markus 848: if ((r = sshbuf_put(state->compression_buffer,
849: "\0\0\0\0\0\0\0\0", 8)) != 0)
850: goto out;
851: if ((r = compress_buffer(ssh, state->outgoing_packet,
852: state->compression_buffer)) != 0)
853: goto out;
854: sshbuf_reset(state->outgoing_packet);
855: if ((r = sshbuf_putb(state->outgoing_packet,
856: state->compression_buffer)) != 0)
857: goto out;
1.14 markus 858: }
859: /* Compute packet length without padding (add checksum, remove padding). */
1.201 markus 860: len = sshbuf_len(state->outgoing_packet) + 4 - 8;
1.14 markus 861:
1.32 markus 862: /* Insert padding. Initialized to zero in packet_start1() */
1.14 markus 863: padding = 8 - len % 8;
1.201 markus 864: if (!state->send_context.plaintext) {
865: cp = sshbuf_mutable_ptr(state->outgoing_packet);
866: if (cp == NULL) {
867: r = SSH_ERR_INTERNAL_ERROR;
868: goto out;
1.14 markus 869: }
1.201 markus 870: arc4random_buf(cp + 8 - padding, padding);
1.14 markus 871: }
1.201 markus 872: if ((r = sshbuf_consume(state->outgoing_packet, 8 - padding)) != 0)
873: goto out;
1.14 markus 874:
875: /* Add check bytes. */
1.201 markus 876: checksum = ssh_crc32(sshbuf_ptr(state->outgoing_packet),
877: sshbuf_len(state->outgoing_packet));
878: POKE_U32(buf, checksum);
879: if ((r = sshbuf_put(state->outgoing_packet, buf, 4)) != 0)
880: goto out;
1.1 deraadt 881:
882: #ifdef PACKET_DEBUG
1.14 markus 883: fprintf(stderr, "packet_send plain: ");
1.201 markus 884: sshbuf_dump(state->outgoing_packet, stderr);
1.1 deraadt 885: #endif
886:
1.14 markus 887: /* Append to output. */
1.201 markus 888: POKE_U32(buf, len);
889: if ((r = sshbuf_put(state->output, buf, 4)) != 0)
890: goto out;
891: if ((r = sshbuf_reserve(state->output,
892: sshbuf_len(state->outgoing_packet), &cp)) != 0)
893: goto out;
894: if ((r = cipher_crypt(&state->send_context, 0, cp,
895: sshbuf_ptr(state->outgoing_packet),
896: sshbuf_len(state->outgoing_packet), 0, 0)) != 0)
897: goto out;
1.14 markus 898:
1.1 deraadt 899: #ifdef PACKET_DEBUG
1.14 markus 900: fprintf(stderr, "encrypted: ");
1.201 markus 901: sshbuf_dump(state->output, stderr);
1.1 deraadt 902: #endif
1.201 markus 903: state->p_send.packets++;
904: state->p_send.bytes += len +
905: sshbuf_len(state->outgoing_packet);
906: sshbuf_reset(state->outgoing_packet);
1.1 deraadt 907:
1.16 markus 908: /*
1.120 djm 909: * Note that the packet is now only buffered in output. It won't be
1.205 djm 910: * actually sent until ssh_packet_write_wait or ssh_packet_write_poll
911: * is called.
1.16 markus 912: */
1.201 markus 913: r = 0;
914: out:
915: return r;
1.1 deraadt 916: }
917:
1.201 markus 918: int
919: ssh_set_newkeys(struct ssh *ssh, int mode)
1.57 markus 920: {
1.201 markus 921: struct session_state *state = ssh->state;
922: struct sshenc *enc;
923: struct sshmac *mac;
924: struct sshcomp *comp;
925: struct sshcipher_ctx *cc;
1.105 markus 926: u_int64_t *max_blocks;
1.201 markus 927: const char *wmsg;
1.197 djm 928: int r, crypt_type;
1.57 markus 929:
1.100 markus 930: debug2("set_newkeys: mode %d", mode);
1.57 markus 931:
1.88 markus 932: if (mode == MODE_OUT) {
1.201 markus 933: cc = &state->send_context;
1.115 avsm 934: crypt_type = CIPHER_ENCRYPT;
1.201 markus 935: state->p_send.packets = state->p_send.blocks = 0;
936: max_blocks = &state->max_blocks_out;
1.88 markus 937: } else {
1.201 markus 938: cc = &state->receive_context;
1.115 avsm 939: crypt_type = CIPHER_DECRYPT;
1.201 markus 940: state->p_read.packets = state->p_read.blocks = 0;
941: max_blocks = &state->max_blocks_in;
1.88 markus 942: }
1.201 markus 943: if (state->newkeys[mode] != NULL) {
1.224 dtucker 944: debug("set_newkeys: rekeying, input %llu bytes %llu blocks, "
945: "output %llu bytes %llu blocks",
1.227 ! djm 946: (unsigned long long)state->p_read.bytes,
! 947: (unsigned long long)state->p_read.blocks,
! 948: (unsigned long long)state->p_send.bytes,
! 949: (unsigned long long)state->p_send.blocks);
1.201 markus 950: if ((r = cipher_cleanup(cc)) != 0)
951: return r;
952: enc = &state->newkeys[mode]->enc;
953: mac = &state->newkeys[mode]->mac;
954: comp = &state->newkeys[mode]->comp;
1.148 pvalchev 955: mac_clear(mac);
1.192 djm 956: explicit_bzero(enc->iv, enc->iv_len);
957: explicit_bzero(enc->key, enc->key_len);
958: explicit_bzero(mac->key, mac->key_len);
1.186 djm 959: free(enc->name);
960: free(enc->iv);
961: free(enc->key);
962: free(mac->name);
963: free(mac->key);
964: free(comp->name);
1.201 markus 965: free(state->newkeys[mode]);
1.57 markus 966: }
1.201 markus 967: /* move newkeys from kex to state */
968: if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
969: return SSH_ERR_INTERNAL_ERROR;
970: ssh->kex->newkeys[mode] = NULL;
971: enc = &state->newkeys[mode]->enc;
972: mac = &state->newkeys[mode]->mac;
973: comp = &state->newkeys[mode]->comp;
974: if (cipher_authlen(enc->cipher) == 0) {
975: if ((r = mac_init(mac)) != 0)
976: return r;
977: }
978: mac->enabled = 1;
1.57 markus 979: DBG(debug("cipher_init_context: %d", mode));
1.197 djm 980: if ((r = cipher_init(cc, enc->cipher, enc->key, enc->key_len,
981: enc->iv, enc->iv_len, crypt_type)) != 0)
1.201 markus 982: return r;
983: if (!state->cipher_warning_done &&
984: (wmsg = cipher_warning_message(cc)) != NULL) {
985: error("Warning: %s", wmsg);
986: state->cipher_warning_done = 1;
987: }
1.91 markus 988: /* Deleting the keys does not gain extra security */
1.192 djm 989: /* explicit_bzero(enc->iv, enc->block_size);
990: explicit_bzero(enc->key, enc->key_len);
991: explicit_bzero(mac->key, mac->key_len); */
1.118 markus 992: if ((comp->type == COMP_ZLIB ||
1.161 andreas 993: (comp->type == COMP_DELAYED &&
1.201 markus 994: state->after_authentication)) && comp->enabled == 0) {
995: if ((r = ssh_packet_init_compression(ssh)) < 0)
996: return r;
997: if (mode == MODE_OUT) {
998: if ((r = start_compression_out(ssh, 6)) != 0)
999: return r;
1000: } else {
1001: if ((r = start_compression_in(ssh)) != 0)
1002: return r;
1003: }
1.57 markus 1004: comp->enabled = 1;
1005: }
1.109 markus 1006: /*
1007: * The 2^(blocksize*2) limit is too expensive for 3DES,
1008: * blowfish, etc, so enforce a 1GB limit for small blocksizes.
1009: */
1010: if (enc->block_size >= 16)
1011: *max_blocks = (u_int64_t)1 << (enc->block_size*2);
1012: else
1013: *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1.201 markus 1014: if (state->rekey_limit)
1.161 andreas 1015: *max_blocks = MIN(*max_blocks,
1.201 markus 1016: state->rekey_limit / enc->block_size);
1.227 ! djm 1017: debug("rekey after %llu blocks", (unsigned long long)*max_blocks);
1.201 markus 1018: return 0;
1.57 markus 1019: }
1020:
1.16 markus 1021: /*
1.118 markus 1022: * Delayed compression for SSH2 is enabled after authentication:
1.143 dtucker 1023: * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1.118 markus 1024: * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
1025: */
1.201 markus 1026: static int
1027: ssh_packet_enable_delayed_compress(struct ssh *ssh)
1.118 markus 1028: {
1.201 markus 1029: struct session_state *state = ssh->state;
1030: struct sshcomp *comp = NULL;
1031: int r, mode;
1.118 markus 1032:
1033: /*
1034: * Remember that we are past the authentication step, so rekeying
1035: * with COMP_DELAYED will turn on compression immediately.
1036: */
1.201 markus 1037: state->after_authentication = 1;
1.118 markus 1038: for (mode = 0; mode < MODE_MAX; mode++) {
1.145 markus 1039: /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1.201 markus 1040: if (state->newkeys[mode] == NULL)
1.145 markus 1041: continue;
1.201 markus 1042: comp = &state->newkeys[mode]->comp;
1.118 markus 1043: if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1.201 markus 1044: if ((r = ssh_packet_init_compression(ssh)) != 0)
1045: return r;
1046: if (mode == MODE_OUT) {
1047: if ((r = start_compression_out(ssh, 6)) != 0)
1048: return r;
1049: } else {
1050: if ((r = start_compression_in(ssh)) != 0)
1051: return r;
1052: }
1.118 markus 1053: comp->enabled = 1;
1054: }
1055: }
1.201 markus 1056: return 0;
1.118 markus 1057: }
1058:
1.226 djm 1059: /* Used to mute debug logging for noisy packet types */
1060: static int
1061: ssh_packet_log_type(u_char type)
1062: {
1063: switch (type) {
1064: case SSH2_MSG_CHANNEL_DATA:
1065: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1066: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1067: return 0;
1068: default:
1069: return 1;
1070: }
1071: }
1072:
1.118 markus 1073: /*
1.25 markus 1074: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1075: */
1.201 markus 1076: int
1077: ssh_packet_send2_wrapped(struct ssh *ssh)
1.25 markus 1078: {
1.201 markus 1079: struct session_state *state = ssh->state;
1.200 markus 1080: u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1.178 markus 1081: u_char padlen, pad = 0;
1.201 markus 1082: u_int authlen = 0, aadlen = 0;
1083: u_int len;
1084: struct sshenc *enc = NULL;
1085: struct sshmac *mac = NULL;
1086: struct sshcomp *comp = NULL;
1087: int r, block_size;
1088:
1089: if (state->newkeys[MODE_OUT] != NULL) {
1090: enc = &state->newkeys[MODE_OUT]->enc;
1091: mac = &state->newkeys[MODE_OUT]->mac;
1092: comp = &state->newkeys[MODE_OUT]->comp;
1.180 markus 1093: /* disable mac for authenticated encryption */
1094: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1095: mac = NULL;
1.25 markus 1096: }
1.88 markus 1097: block_size = enc ? enc->block_size : 8;
1.180 markus 1098: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1099:
1.201 markus 1100: type = (sshbuf_ptr(state->outgoing_packet))[5];
1.226 djm 1101: if (ssh_packet_log_type(type))
1102: debug3("send packet: type %u", type);
1.25 markus 1103: #ifdef PACKET_DEBUG
1104: fprintf(stderr, "plain: ");
1.201 markus 1105: sshbuf_dump(state->outgoing_packet, stderr);
1.25 markus 1106: #endif
1107:
1108: if (comp && comp->enabled) {
1.201 markus 1109: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1110: /* skip header, compress only payload */
1.201 markus 1111: if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1112: goto out;
1113: sshbuf_reset(state->compression_buffer);
1114: if ((r = compress_buffer(ssh, state->outgoing_packet,
1115: state->compression_buffer)) != 0)
1116: goto out;
1117: sshbuf_reset(state->outgoing_packet);
1118: if ((r = sshbuf_put(state->outgoing_packet,
1119: "\0\0\0\0\0", 5)) != 0 ||
1120: (r = sshbuf_putb(state->outgoing_packet,
1121: state->compression_buffer)) != 0)
1122: goto out;
1123: DBG(debug("compression: raw %d compressed %zd", len,
1124: sshbuf_len(state->outgoing_packet)));
1.25 markus 1125: }
1126:
1127: /* sizeof (packet_len + pad_len + payload) */
1.201 markus 1128: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1129:
1130: /*
1131: * calc size of padding, alloc space, get random data,
1132: * minimum padding is 4 bytes
1133: */
1.178 markus 1134: len -= aadlen; /* packet length is not encrypted for EtM modes */
1.25 markus 1135: padlen = block_size - (len % block_size);
1136: if (padlen < 4)
1137: padlen += block_size;
1.201 markus 1138: if (state->extra_pad) {
1.71 markus 1139: /* will wrap if extra_pad+padlen > 255 */
1.201 markus 1140: state->extra_pad =
1141: roundup(state->extra_pad, block_size);
1142: pad = state->extra_pad -
1143: ((len + padlen) % state->extra_pad);
1.193 djm 1144: DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1.201 markus 1145: __func__, pad, len, padlen, state->extra_pad));
1.71 markus 1146: padlen += pad;
1.201 markus 1147: state->extra_pad = 0;
1.71 markus 1148: }
1.201 markus 1149: if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1150: goto out;
1151: if (enc && !state->send_context.plaintext) {
1.32 markus 1152: /* random padding */
1.201 markus 1153: arc4random_buf(cp, padlen);
1.32 markus 1154: } else {
1155: /* clear padding */
1.192 djm 1156: explicit_bzero(cp, padlen);
1.25 markus 1157: }
1.178 markus 1158: /* sizeof (packet_len + pad_len + payload + padding) */
1.201 markus 1159: len = sshbuf_len(state->outgoing_packet);
1160: cp = sshbuf_mutable_ptr(state->outgoing_packet);
1161: if (cp == NULL) {
1162: r = SSH_ERR_INTERNAL_ERROR;
1163: goto out;
1164: }
1.25 markus 1165: /* packet_length includes payload, padding and padding length field */
1.201 markus 1166: POKE_U32(cp, len - 4);
1.89 markus 1167: cp[4] = padlen;
1.178 markus 1168: DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1169: len, padlen, aadlen));
1.25 markus 1170:
1171: /* compute MAC over seqnr and packet(length fields, payload, padding) */
1.178 markus 1172: if (mac && mac->enabled && !mac->etm) {
1.201 markus 1173: if ((r = mac_compute(mac, state->p_send.seqnr,
1174: sshbuf_ptr(state->outgoing_packet), len,
1.200 markus 1175: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1176: goto out;
1177: DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1.25 markus 1178: }
1179: /* encrypt packet and append to output buffer. */
1.201 markus 1180: if ((r = sshbuf_reserve(state->output,
1181: sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1182: goto out;
1183: if ((r = cipher_crypt(&state->send_context, state->p_send.seqnr, cp,
1184: sshbuf_ptr(state->outgoing_packet),
1185: len - aadlen, aadlen, authlen)) != 0)
1186: goto out;
1.25 markus 1187: /* append unencrypted MAC */
1.178 markus 1188: if (mac && mac->enabled) {
1189: if (mac->etm) {
1190: /* EtM: compute mac over aadlen + cipher text */
1.201 markus 1191: if ((r = mac_compute(mac, state->p_send.seqnr,
1192: cp, len, macbuf, sizeof(macbuf))) != 0)
1193: goto out;
1.178 markus 1194: DBG(debug("done calc MAC(EtM) out #%d",
1.201 markus 1195: state->p_send.seqnr));
1.178 markus 1196: }
1.201 markus 1197: if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1198: goto out;
1.178 markus 1199: }
1.25 markus 1200: #ifdef PACKET_DEBUG
1201: fprintf(stderr, "encrypted: ");
1.201 markus 1202: sshbuf_dump(state->output, stderr);
1.25 markus 1203: #endif
1.29 markus 1204: /* increment sequence number for outgoing packets */
1.201 markus 1205: if (++state->p_send.seqnr == 0)
1.106 itojun 1206: logit("outgoing seqnr wraps around");
1.201 markus 1207: if (++state->p_send.packets == 0)
1208: if (!(ssh->compat & SSH_BUG_NOREKEY))
1209: return SSH_ERR_NEED_REKEY;
1210: state->p_send.blocks += len / block_size;
1211: state->p_send.bytes += len;
1212: sshbuf_reset(state->outgoing_packet);
1.25 markus 1213:
1.57 markus 1214: if (type == SSH2_MSG_NEWKEYS)
1.201 markus 1215: r = ssh_set_newkeys(ssh, MODE_OUT);
1216: else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1217: r = ssh_packet_enable_delayed_compress(ssh);
1218: else
1219: r = 0;
1220: out:
1221: return r;
1.25 markus 1222: }
1223:
1.201 markus 1224: int
1225: ssh_packet_send2(struct ssh *ssh)
1.105 markus 1226: {
1.201 markus 1227: struct session_state *state = ssh->state;
1.105 markus 1228: struct packet *p;
1.201 markus 1229: u_char type;
1230: int r;
1.105 markus 1231:
1.201 markus 1232: type = sshbuf_ptr(state->outgoing_packet)[5];
1.105 markus 1233:
1234: /* during rekeying we can only send key exchange messages */
1.201 markus 1235: if (state->rekeying) {
1.175 markus 1236: if ((type < SSH2_MSG_TRANSPORT_MIN) ||
1237: (type > SSH2_MSG_TRANSPORT_MAX) ||
1238: (type == SSH2_MSG_SERVICE_REQUEST) ||
1.218 markus 1239: (type == SSH2_MSG_SERVICE_ACCEPT) ||
1240: (type == SSH2_MSG_EXT_INFO)) {
1.105 markus 1241: debug("enqueue packet: %u", type);
1.201 markus 1242: p = calloc(1, sizeof(*p));
1243: if (p == NULL)
1244: return SSH_ERR_ALLOC_FAIL;
1.105 markus 1245: p->type = type;
1.201 markus 1246: p->payload = state->outgoing_packet;
1247: TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1248: state->outgoing_packet = sshbuf_new();
1249: if (state->outgoing_packet == NULL)
1250: return SSH_ERR_ALLOC_FAIL;
1251: return 0;
1.105 markus 1252: }
1253: }
1254:
1255: /* rekeying starts with sending KEXINIT */
1256: if (type == SSH2_MSG_KEXINIT)
1.201 markus 1257: state->rekeying = 1;
1.105 markus 1258:
1.201 markus 1259: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1260: return r;
1.105 markus 1261:
1262: /* after a NEWKEYS message we can send the complete queue */
1263: if (type == SSH2_MSG_NEWKEYS) {
1.201 markus 1264: state->rekeying = 0;
1265: state->rekey_time = monotime();
1266: while ((p = TAILQ_FIRST(&state->outgoing))) {
1.105 markus 1267: type = p->type;
1268: debug("dequeue packet: %u", type);
1.201 markus 1269: sshbuf_free(state->outgoing_packet);
1270: state->outgoing_packet = p->payload;
1271: TAILQ_REMOVE(&state->outgoing, p, next);
1.186 djm 1272: free(p);
1.201 markus 1273: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1274: return r;
1.105 markus 1275: }
1276: }
1.201 markus 1277: return 0;
1.25 markus 1278: }
1279:
1280: /*
1.16 markus 1281: * Waits until a packet has been received, and returns its type. Note that
1282: * no other data is processed until this returns, so this function should not
1283: * be used during the interactive session.
1284: */
1.1 deraadt 1285:
1.2 provos 1286: int
1.201 markus 1287: ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.1 deraadt 1288: {
1.201 markus 1289: struct session_state *state = ssh->state;
1.222 markus 1290: int len, r, ms_remain;
1.56 millert 1291: fd_set *setp;
1.14 markus 1292: char buf[8192];
1.155 deraadt 1293: struct timeval timeout, start, *timeoutp = NULL;
1294:
1.25 markus 1295: DBG(debug("packet_read()"));
1.14 markus 1296:
1.214 deraadt 1297: setp = calloc(howmany(state->connection_in + 1,
1.161 andreas 1298: NFDBITS), sizeof(fd_mask));
1.201 markus 1299: if (setp == NULL)
1300: return SSH_ERR_ALLOC_FAIL;
1.56 millert 1301:
1.205 djm 1302: /*
1303: * Since we are blocking, ensure that all written packets have
1304: * been sent.
1305: */
1.210 markus 1306: if ((r = ssh_packet_write_wait(ssh)) != 0)
1307: goto out;
1.14 markus 1308:
1309: /* Stay in the loop until we have received a complete packet. */
1310: for (;;) {
1311: /* Try to read a packet from the buffer. */
1.201 markus 1312: r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1313: if (r != 0)
1314: break;
1.62 markus 1315: if (!compat20 && (
1.201 markus 1316: *typep == SSH_SMSG_SUCCESS
1317: || *typep == SSH_SMSG_FAILURE
1318: || *typep == SSH_CMSG_EOF
1319: || *typep == SSH_CMSG_EXIT_CONFIRMATION))
1320: if ((r = sshpkt_get_end(ssh)) != 0)
1321: break;
1.14 markus 1322: /* If we got a packet, return it. */
1.201 markus 1323: if (*typep != SSH_MSG_NONE)
1324: break;
1.16 markus 1325: /*
1326: * Otherwise, wait for some data to arrive, add it to the
1327: * buffer, and try again.
1328: */
1.201 markus 1329: memset(setp, 0, howmany(state->connection_in + 1,
1.161 andreas 1330: NFDBITS) * sizeof(fd_mask));
1.201 markus 1331: FD_SET(state->connection_in, setp);
1.16 markus 1332:
1.201 markus 1333: if (state->packet_timeout_ms > 0) {
1334: ms_remain = state->packet_timeout_ms;
1.154 dtucker 1335: timeoutp = &timeout;
1336: }
1.14 markus 1337: /* Wait for some data to arrive. */
1.154 dtucker 1338: for (;;) {
1.201 markus 1339: if (state->packet_timeout_ms != -1) {
1.154 dtucker 1340: ms_to_timeval(&timeout, ms_remain);
1341: gettimeofday(&start, NULL);
1342: }
1.201 markus 1343: if ((r = select(state->connection_in + 1, setp,
1.161 andreas 1344: NULL, NULL, timeoutp)) >= 0)
1.154 dtucker 1345: break;
1.161 andreas 1346: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 1347: break;
1.201 markus 1348: if (state->packet_timeout_ms == -1)
1.154 dtucker 1349: continue;
1350: ms_subtract_diff(&start, &ms_remain);
1351: if (ms_remain <= 0) {
1.201 markus 1352: r = 0;
1.154 dtucker 1353: break;
1354: }
1355: }
1.204 djm 1356: if (r == 0)
1357: return SSH_ERR_CONN_TIMEOUT;
1.14 markus 1358: /* Read data from the socket. */
1.222 markus 1359: len = read(state->connection_in, buf, sizeof(buf));
1.210 markus 1360: if (len == 0) {
1361: r = SSH_ERR_CONN_CLOSED;
1362: goto out;
1363: }
1364: if (len < 0) {
1365: r = SSH_ERR_SYSTEM_ERROR;
1366: goto out;
1367: }
1.204 djm 1368:
1.14 markus 1369: /* Append it to the buffer. */
1.204 djm 1370: if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1.210 markus 1371: goto out;
1.14 markus 1372: }
1.210 markus 1373: out:
1.201 markus 1374: free(setp);
1375: return r;
1.1 deraadt 1376: }
1377:
1.77 djm 1378: int
1.201 markus 1379: ssh_packet_read(struct ssh *ssh)
1.77 djm 1380: {
1.201 markus 1381: u_char type;
1382: int r;
1383:
1384: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1385: fatal("%s: %s", __func__, ssh_err(r));
1386: return type;
1.77 djm 1387: }
1388:
1.16 markus 1389: /*
1390: * Waits until a packet has been received, verifies that its type matches
1391: * that given, and gives a fatal error and exits if there is a mismatch.
1392: */
1.1 deraadt 1393:
1.205 djm 1394: int
1395: ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1.1 deraadt 1396: {
1.205 djm 1397: int r;
1398: u_char type;
1.1 deraadt 1399:
1.205 djm 1400: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1401: return r;
1402: if (type != expected_type) {
1403: if ((r = sshpkt_disconnect(ssh,
1.201 markus 1404: "Protocol error: expected packet type %d, got %d",
1.205 djm 1405: expected_type, type)) != 0)
1406: return r;
1407: return SSH_ERR_PROTOCOL_ERROR;
1408: }
1409: return 0;
1.1 deraadt 1410: }
1411:
1412: /* Checks if a full packet is available in the data received so far via
1.14 markus 1413: * packet_process_incoming. If so, reads the packet; otherwise returns
1414: * SSH_MSG_NONE. This does not wait for data from the connection.
1415: *
1.150 dtucker 1416: * SSH_MSG_DISCONNECT is handled specially here. Also,
1417: * SSH_MSG_IGNORE messages are skipped by this function and are never returned
1418: * to higher levels.
1.14 markus 1419: */
1.1 deraadt 1420:
1.201 markus 1421: int
1422: ssh_packet_read_poll1(struct ssh *ssh, u_char *typep)
1.1 deraadt 1423: {
1.201 markus 1424: struct session_state *state = ssh->state;
1.40 markus 1425: u_int len, padded_len;
1.205 djm 1426: const char *emsg;
1.201 markus 1427: const u_char *cp;
1428: u_char *p;
1.40 markus 1429: u_int checksum, stored_checksum;
1.201 markus 1430: int r;
1431:
1432: *typep = SSH_MSG_NONE;
1.14 markus 1433:
1434: /* Check if input size is less than minimum packet size. */
1.201 markus 1435: if (sshbuf_len(state->input) < 4 + 8)
1436: return 0;
1.14 markus 1437: /* Get length of incoming packet. */
1.201 markus 1438: len = PEEK_U32(sshbuf_ptr(state->input));
1.205 djm 1439: if (len < 1 + 2 + 2 || len > 256 * 1024) {
1440: if ((r = sshpkt_disconnect(ssh, "Bad packet length %u",
1441: len)) != 0)
1442: return r;
1443: return SSH_ERR_CONN_CORRUPT;
1444: }
1.14 markus 1445: padded_len = (len + 8) & ~7;
1446:
1447: /* Check if the packet has been entirely received. */
1.201 markus 1448: if (sshbuf_len(state->input) < 4 + padded_len)
1449: return 0;
1.14 markus 1450:
1451: /* The entire packet is in buffer. */
1452:
1453: /* Consume packet length. */
1.201 markus 1454: if ((r = sshbuf_consume(state->input, 4)) != 0)
1455: goto out;
1.14 markus 1456:
1.62 markus 1457: /*
1458: * Cryptographic attack detector for ssh
1459: * (C)1998 CORE-SDI, Buenos Aires Argentina
1460: * Ariel Futoransky(futo@core-sdi.com)
1461: */
1.201 markus 1462: if (!state->receive_context.plaintext) {
1.205 djm 1463: emsg = NULL;
1.201 markus 1464: switch (detect_attack(&state->deattack,
1465: sshbuf_ptr(state->input), padded_len)) {
1466: case DEATTACK_OK:
1467: break;
1.144 djm 1468: case DEATTACK_DETECTED:
1.205 djm 1469: emsg = "crc32 compensation attack detected";
1470: break;
1.144 djm 1471: case DEATTACK_DOS_DETECTED:
1.205 djm 1472: emsg = "deattack denial of service detected";
1473: break;
1.201 markus 1474: default:
1.205 djm 1475: emsg = "deattack error";
1476: break;
1477: }
1478: if (emsg != NULL) {
1479: error("%s", emsg);
1480: if ((r = sshpkt_disconnect(ssh, "%s", emsg)) != 0 ||
1481: (r = ssh_packet_write_wait(ssh)) != 0)
1482: return r;
1483: return SSH_ERR_CONN_CORRUPT;
1.144 djm 1484: }
1485: }
1.62 markus 1486:
1487: /* Decrypt data to incoming_packet. */
1.201 markus 1488: sshbuf_reset(state->incoming_packet);
1489: if ((r = sshbuf_reserve(state->incoming_packet, padded_len, &p)) != 0)
1490: goto out;
1491: if ((r = cipher_crypt(&state->receive_context, 0, p,
1492: sshbuf_ptr(state->input), padded_len, 0, 0)) != 0)
1493: goto out;
1.62 markus 1494:
1.201 markus 1495: if ((r = sshbuf_consume(state->input, padded_len)) != 0)
1496: goto out;
1.1 deraadt 1497:
1498: #ifdef PACKET_DEBUG
1.14 markus 1499: fprintf(stderr, "read_poll plain: ");
1.201 markus 1500: sshbuf_dump(state->incoming_packet, stderr);
1.1 deraadt 1501: #endif
1502:
1.14 markus 1503: /* Compute packet checksum. */
1.201 markus 1504: checksum = ssh_crc32(sshbuf_ptr(state->incoming_packet),
1505: sshbuf_len(state->incoming_packet) - 4);
1.14 markus 1506:
1507: /* Skip padding. */
1.201 markus 1508: if ((r = sshbuf_consume(state->incoming_packet, 8 - len % 8)) != 0)
1509: goto out;
1.14 markus 1510:
1511: /* Test check bytes. */
1.205 djm 1512: if (len != sshbuf_len(state->incoming_packet)) {
1513: error("%s: len %d != sshbuf_len %zd", __func__,
1.201 markus 1514: len, sshbuf_len(state->incoming_packet));
1.205 djm 1515: if ((r = sshpkt_disconnect(ssh, "invalid packet length")) != 0 ||
1516: (r = ssh_packet_write_wait(ssh)) != 0)
1517: return r;
1518: return SSH_ERR_CONN_CORRUPT;
1519: }
1.14 markus 1520:
1.201 markus 1521: cp = sshbuf_ptr(state->incoming_packet) + len - 4;
1522: stored_checksum = PEEK_U32(cp);
1.205 djm 1523: if (checksum != stored_checksum) {
1524: error("Corrupted check bytes on input");
1525: if ((r = sshpkt_disconnect(ssh, "connection corrupted")) != 0 ||
1526: (r = ssh_packet_write_wait(ssh)) != 0)
1527: return r;
1528: return SSH_ERR_CONN_CORRUPT;
1529: }
1.201 markus 1530: if ((r = sshbuf_consume_end(state->incoming_packet, 4)) < 0)
1531: goto out;
1532:
1533: if (state->packet_compression) {
1534: sshbuf_reset(state->compression_buffer);
1535: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1536: state->compression_buffer)) != 0)
1537: goto out;
1538: sshbuf_reset(state->incoming_packet);
1539: if ((r = sshbuf_putb(state->incoming_packet,
1540: state->compression_buffer)) != 0)
1541: goto out;
1542: }
1543: state->p_read.packets++;
1544: state->p_read.bytes += padded_len + 4;
1545: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1546: goto out;
1.205 djm 1547: if (*typep < SSH_MSG_MIN || *typep > SSH_MSG_MAX) {
1548: error("Invalid ssh1 packet type: %d", *typep);
1549: if ((r = sshpkt_disconnect(ssh, "invalid packet type")) != 0 ||
1550: (r = ssh_packet_write_wait(ssh)) != 0)
1551: return r;
1552: return SSH_ERR_PROTOCOL_ERROR;
1553: }
1.201 markus 1554: r = 0;
1555: out:
1556: return r;
1.1 deraadt 1557: }
1.14 markus 1558:
1.201 markus 1559: int
1560: ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1561: {
1.201 markus 1562: struct session_state *state = ssh->state;
1.40 markus 1563: u_int padlen, need;
1.201 markus 1564: u_char *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1565: u_int maclen, aadlen = 0, authlen = 0, block_size;
1566: struct sshenc *enc = NULL;
1567: struct sshmac *mac = NULL;
1568: struct sshcomp *comp = NULL;
1.200 markus 1569: int r;
1.201 markus 1570:
1571: *typep = SSH_MSG_NONE;
1572:
1573: if (state->packet_discard)
1574: return 0;
1575:
1576: if (state->newkeys[MODE_IN] != NULL) {
1577: enc = &state->newkeys[MODE_IN]->enc;
1578: mac = &state->newkeys[MODE_IN]->mac;
1579: comp = &state->newkeys[MODE_IN]->comp;
1.180 markus 1580: /* disable mac for authenticated encryption */
1581: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1582: mac = NULL;
1.25 markus 1583: }
1584: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.88 markus 1585: block_size = enc ? enc->block_size : 8;
1.180 markus 1586: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1587:
1.201 markus 1588: if (aadlen && state->packlen == 0) {
1589: if (cipher_get_length(&state->receive_context,
1590: &state->packlen, state->p_read.seqnr,
1591: sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1592: return 0;
1593: if (state->packlen < 1 + 4 ||
1594: state->packlen > PACKET_MAX_SIZE) {
1.178 markus 1595: #ifdef PACKET_DEBUG
1.201 markus 1596: sshbuf_dump(state->input, stderr);
1.178 markus 1597: #endif
1.201 markus 1598: logit("Bad packet length %u.", state->packlen);
1599: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1600: return r;
1.217 djm 1601: return SSH_ERR_CONN_CORRUPT;
1.178 markus 1602: }
1.201 markus 1603: sshbuf_reset(state->incoming_packet);
1604: } else if (state->packlen == 0) {
1.25 markus 1605: /*
1606: * check if input size is less than the cipher block size,
1607: * decrypt first block and extract length of incoming packet
1608: */
1.201 markus 1609: if (sshbuf_len(state->input) < block_size)
1610: return 0;
1611: sshbuf_reset(state->incoming_packet);
1612: if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1613: &cp)) != 0)
1614: goto out;
1615: if ((r = cipher_crypt(&state->receive_context,
1616: state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1617: block_size, 0, 0)) != 0)
1618: goto out;
1619: state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1620: if (state->packlen < 1 + 4 ||
1621: state->packlen > PACKET_MAX_SIZE) {
1.110 markus 1622: #ifdef PACKET_DEBUG
1.201 markus 1623: fprintf(stderr, "input: \n");
1624: sshbuf_dump(state->input, stderr);
1625: fprintf(stderr, "incoming_packet: \n");
1626: sshbuf_dump(state->incoming_packet, stderr);
1.110 markus 1627: #endif
1.201 markus 1628: logit("Bad packet length %u.", state->packlen);
1629: return ssh_packet_start_discard(ssh, enc, mac,
1630: state->packlen, PACKET_MAX_SIZE);
1.25 markus 1631: }
1.201 markus 1632: if ((r = sshbuf_consume(state->input, block_size)) != 0)
1633: goto out;
1.25 markus 1634: }
1.201 markus 1635: DBG(debug("input: packet len %u", state->packlen+4));
1636:
1.178 markus 1637: if (aadlen) {
1638: /* only the payload is encrypted */
1.201 markus 1639: need = state->packlen;
1.178 markus 1640: } else {
1641: /*
1642: * the payload size and the payload are encrypted, but we
1643: * have a partial packet of block_size bytes
1644: */
1.201 markus 1645: need = 4 + state->packlen - block_size;
1.178 markus 1646: }
1.180 markus 1647: DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1648: " aadlen %d", block_size, need, maclen, authlen, aadlen));
1.158 markus 1649: if (need % block_size != 0) {
1650: logit("padding error: need %d block %d mod %d",
1.25 markus 1651: need, block_size, need % block_size);
1.201 markus 1652: return ssh_packet_start_discard(ssh, enc, mac,
1653: state->packlen, PACKET_MAX_SIZE - block_size);
1.158 markus 1654: }
1.25 markus 1655: /*
1656: * check if the entire packet has been received and
1.178 markus 1657: * decrypt into incoming_packet:
1658: * 'aadlen' bytes are unencrypted, but authenticated.
1.180 markus 1659: * 'need' bytes are encrypted, followed by either
1660: * 'authlen' bytes of authentication tag or
1.178 markus 1661: * 'maclen' bytes of message authentication code.
1.25 markus 1662: */
1.201 markus 1663: if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1664: return 0;
1.25 markus 1665: #ifdef PACKET_DEBUG
1666: fprintf(stderr, "read_poll enc/full: ");
1.201 markus 1667: sshbuf_dump(state->input, stderr);
1.25 markus 1668: #endif
1.178 markus 1669: /* EtM: compute mac over encrypted input */
1.201 markus 1670: if (mac && mac->enabled && mac->etm) {
1671: if ((r = mac_compute(mac, state->p_read.seqnr,
1672: sshbuf_ptr(state->input), aadlen + need,
1.200 markus 1673: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1674: goto out;
1675: }
1676: if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1677: &cp)) != 0)
1678: goto out;
1679: if ((r = cipher_crypt(&state->receive_context, state->p_read.seqnr, cp,
1680: sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1681: goto out;
1682: if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1683: goto out;
1.25 markus 1684: /*
1685: * compute MAC over seqnr and packet,
1686: * increment sequence number for incoming packet
1687: */
1.29 markus 1688: if (mac && mac->enabled) {
1.178 markus 1689: if (!mac->etm)
1.201 markus 1690: if ((r = mac_compute(mac, state->p_read.seqnr,
1691: sshbuf_ptr(state->incoming_packet),
1692: sshbuf_len(state->incoming_packet),
1.200 markus 1693: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1694: goto out;
1695: if (timingsafe_bcmp(macbuf, sshbuf_ptr(state->input),
1.161 andreas 1696: mac->mac_len) != 0) {
1.159 markus 1697: logit("Corrupted MAC on input.");
1698: if (need > PACKET_MAX_SIZE)
1.201 markus 1699: return SSH_ERR_INTERNAL_ERROR;
1700: return ssh_packet_start_discard(ssh, enc, mac,
1701: state->packlen, PACKET_MAX_SIZE - need);
1702: }
1703:
1704: DBG(debug("MAC #%d ok", state->p_read.seqnr));
1705: if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1706: goto out;
1.25 markus 1707: }
1.77 djm 1708: if (seqnr_p != NULL)
1.201 markus 1709: *seqnr_p = state->p_read.seqnr;
1710: if (++state->p_read.seqnr == 0)
1.106 itojun 1711: logit("incoming seqnr wraps around");
1.201 markus 1712: if (++state->p_read.packets == 0)
1713: if (!(ssh->compat & SSH_BUG_NOREKEY))
1714: return SSH_ERR_NEED_REKEY;
1715: state->p_read.blocks += (state->packlen + 4) / block_size;
1716: state->p_read.bytes += state->packlen + 4;
1.25 markus 1717:
1718: /* get padlen */
1.201 markus 1719: padlen = sshbuf_ptr(state->incoming_packet)[4];
1.25 markus 1720: DBG(debug("input: padlen %d", padlen));
1.205 djm 1721: if (padlen < 4) {
1722: if ((r = sshpkt_disconnect(ssh,
1723: "Corrupted padlen %d on input.", padlen)) != 0 ||
1724: (r = ssh_packet_write_wait(ssh)) != 0)
1725: return r;
1726: return SSH_ERR_CONN_CORRUPT;
1727: }
1.25 markus 1728:
1729: /* skip packet size + padlen, discard padding */
1.201 markus 1730: if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1731: ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1732: goto out;
1.25 markus 1733:
1.201 markus 1734: DBG(debug("input: len before de-compress %zd",
1735: sshbuf_len(state->incoming_packet)));
1.25 markus 1736: if (comp && comp->enabled) {
1.201 markus 1737: sshbuf_reset(state->compression_buffer);
1738: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1739: state->compression_buffer)) != 0)
1740: goto out;
1741: sshbuf_reset(state->incoming_packet);
1742: if ((r = sshbuf_putb(state->incoming_packet,
1743: state->compression_buffer)) != 0)
1744: goto out;
1745: DBG(debug("input: len after de-compress %zd",
1746: sshbuf_len(state->incoming_packet)));
1.25 markus 1747: }
1748: /*
1749: * get packet type, implies consume.
1750: * return length of payload (without type field)
1751: */
1.201 markus 1752: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1753: goto out;
1.226 djm 1754: if (ssh_packet_log_type(*typep))
1755: debug3("receive packet: type %u", *typep);
1.205 djm 1756: if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1757: if ((r = sshpkt_disconnect(ssh,
1758: "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1759: (r = ssh_packet_write_wait(ssh)) != 0)
1760: return r;
1761: return SSH_ERR_PROTOCOL_ERROR;
1762: }
1.201 markus 1763: if (*typep == SSH2_MSG_NEWKEYS)
1764: r = ssh_set_newkeys(ssh, MODE_IN);
1765: else if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1766: r = ssh_packet_enable_delayed_compress(ssh);
1767: else
1768: r = 0;
1.25 markus 1769: #ifdef PACKET_DEBUG
1.201 markus 1770: fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1771: sshbuf_dump(state->incoming_packet, stderr);
1.25 markus 1772: #endif
1.62 markus 1773: /* reset for next packet */
1.201 markus 1774: state->packlen = 0;
1775: out:
1776: return r;
1.25 markus 1777: }
1778:
1779: int
1.201 markus 1780: ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1781: {
1.201 markus 1782: struct session_state *state = ssh->state;
1.96 deraadt 1783: u_int reason, seqnr;
1.201 markus 1784: int r;
1785: u_char *msg;
1.62 markus 1786:
1.25 markus 1787: for (;;) {
1.201 markus 1788: msg = NULL;
1.62 markus 1789: if (compat20) {
1.201 markus 1790: r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1791: if (r != 0)
1792: return r;
1793: if (*typep) {
1794: state->keep_alive_timeouts = 0;
1795: DBG(debug("received packet type %d", *typep));
1.153 djm 1796: }
1.201 markus 1797: switch (*typep) {
1.150 dtucker 1798: case SSH2_MSG_IGNORE:
1.151 dtucker 1799: debug3("Received SSH2_MSG_IGNORE");
1.150 dtucker 1800: break;
1.25 markus 1801: case SSH2_MSG_DEBUG:
1.201 markus 1802: if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1803: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1804: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1.219 mmcc 1805: free(msg);
1.201 markus 1806: return r;
1807: }
1.25 markus 1808: debug("Remote: %.900s", msg);
1.186 djm 1809: free(msg);
1.25 markus 1810: break;
1811: case SSH2_MSG_DISCONNECT:
1.201 markus 1812: if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1813: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1814: return r;
1.182 djm 1815: /* Ignore normal client exit notifications */
1.201 markus 1816: do_log2(ssh->state->server_side &&
1.182 djm 1817: reason == SSH2_DISCONNECT_BY_APPLICATION ?
1818: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1.220 djm 1819: "Received disconnect from %s port %d:"
1820: "%u: %.400s", ssh_remote_ipaddr(ssh),
1821: ssh_remote_port(ssh), reason, msg);
1.186 djm 1822: free(msg);
1.201 markus 1823: return SSH_ERR_DISCONNECTED;
1.84 markus 1824: case SSH2_MSG_UNIMPLEMENTED:
1.201 markus 1825: if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1826: return r;
1.96 deraadt 1827: debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1828: seqnr);
1.150 dtucker 1829: break;
1.25 markus 1830: default:
1.201 markus 1831: return 0;
1.48 stevesk 1832: }
1.25 markus 1833: } else {
1.201 markus 1834: r = ssh_packet_read_poll1(ssh, typep);
1835: switch (*typep) {
1.188 djm 1836: case SSH_MSG_NONE:
1837: return SSH_MSG_NONE;
1.25 markus 1838: case SSH_MSG_IGNORE:
1839: break;
1840: case SSH_MSG_DEBUG:
1.201 markus 1841: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1842: return r;
1.25 markus 1843: debug("Remote: %.900s", msg);
1.186 djm 1844: free(msg);
1.25 markus 1845: break;
1846: case SSH_MSG_DISCONNECT:
1.201 markus 1847: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1848: return r;
1.220 djm 1849: error("Received disconnect from %s port %d: "
1850: "%.400s", ssh_remote_ipaddr(ssh),
1851: ssh_remote_port(ssh), msg);
1.201 markus 1852: free(msg);
1853: return SSH_ERR_DISCONNECTED;
1.25 markus 1854: default:
1.201 markus 1855: DBG(debug("received packet type %d", *typep));
1856: return 0;
1.48 stevesk 1857: }
1.25 markus 1858: }
1859: }
1860: }
1861:
1.16 markus 1862: /*
1863: * Buffers the given amount of input characters. This is intended to be used
1864: * together with packet_read_poll.
1865: */
1.1 deraadt 1866:
1.204 djm 1867: int
1.201 markus 1868: ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1.1 deraadt 1869: {
1.201 markus 1870: struct session_state *state = ssh->state;
1871: int r;
1872:
1873: if (state->packet_discard) {
1874: state->keep_alive_timeouts = 0; /* ?? */
1875: if (len >= state->packet_discard) {
1876: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1.204 djm 1877: return r;
1.201 markus 1878: }
1879: state->packet_discard -= len;
1.204 djm 1880: return 0;
1.159 markus 1881: }
1.201 markus 1882: if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1.204 djm 1883: return r;
1884:
1885: return 0;
1.28 markus 1886: }
1887:
1888: int
1.201 markus 1889: ssh_packet_remaining(struct ssh *ssh)
1.28 markus 1890: {
1.201 markus 1891: return sshbuf_len(ssh->state->incoming_packet);
1.1 deraadt 1892: }
1893:
1.16 markus 1894: /*
1895: * Sends a diagnostic message from the server to the client. This message
1896: * can be sent at any time (but not while constructing another message). The
1897: * message is printed immediately, but only if the client is being executed
1898: * in verbose mode. These messages are primarily intended to ease debugging
1899: * authentication problems. The length of the formatted message must not
1.205 djm 1900: * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1.16 markus 1901: */
1.2 provos 1902: void
1.201 markus 1903: ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1904: {
1.14 markus 1905: char buf[1024];
1906: va_list args;
1.201 markus 1907: int r;
1.39 markus 1908:
1.201 markus 1909: if (compat20 && (ssh->compat & SSH_BUG_DEBUG))
1.39 markus 1910: return;
1.14 markus 1911:
1912: va_start(args, fmt);
1913: vsnprintf(buf, sizeof(buf), fmt, args);
1914: va_end(args);
1915:
1.30 markus 1916: if (compat20) {
1.201 markus 1917: if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1918: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1919: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1920: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1921: (r = sshpkt_send(ssh)) != 0)
1922: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1923: } else {
1.201 markus 1924: if ((r = sshpkt_start(ssh, SSH_MSG_DEBUG)) != 0 ||
1925: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1926: (r = sshpkt_send(ssh)) != 0)
1927: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1928: }
1.205 djm 1929: if ((r = ssh_packet_write_wait(ssh)) != 0)
1930: fatal("%s: %s", __func__, ssh_err(r));
1931: }
1932:
1933: /*
1934: * Pretty-print connection-terminating errors and exit.
1935: */
1936: void
1937: sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1938: {
1939: switch (r) {
1940: case SSH_ERR_CONN_CLOSED:
1.220 djm 1941: logit("Connection closed by %.200s port %d",
1942: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.205 djm 1943: cleanup_exit(255);
1944: case SSH_ERR_CONN_TIMEOUT:
1.220 djm 1945: logit("Connection %s %.200s port %d timed out",
1946: ssh->state->server_side ? "from" : "to",
1947: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.205 djm 1948: cleanup_exit(255);
1.212 djm 1949: case SSH_ERR_DISCONNECTED:
1.220 djm 1950: logit("Disconnected from %.200s port %d",
1951: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 1952: cleanup_exit(255);
1953: case SSH_ERR_SYSTEM_ERROR:
1954: if (errno == ECONNRESET) {
1.220 djm 1955: logit("Connection reset by %.200s port %d",
1956: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 1957: cleanup_exit(255);
1.213 djm 1958: }
1959: /* FALLTHROUGH */
1960: case SSH_ERR_NO_CIPHER_ALG_MATCH:
1961: case SSH_ERR_NO_MAC_ALG_MATCH:
1962: case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1963: case SSH_ERR_NO_KEX_ALG_MATCH:
1964: case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1965: if (ssh && ssh->kex && ssh->kex->failed_choice) {
1.220 djm 1966: fatal("Unable to negotiate with %.200s port %d: %s. "
1.213 djm 1967: "Their offer: %s", ssh_remote_ipaddr(ssh),
1.220 djm 1968: ssh_remote_port(ssh), ssh_err(r),
1969: ssh->kex->failed_choice);
1.212 djm 1970: }
1971: /* FALLTHROUGH */
1.205 djm 1972: default:
1.220 djm 1973: fatal("%s%sConnection %s %.200s port %d: %s",
1.205 djm 1974: tag != NULL ? tag : "", tag != NULL ? ": " : "",
1.220 djm 1975: ssh->state->server_side ? "from" : "to",
1976: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), ssh_err(r));
1.205 djm 1977: }
1.1 deraadt 1978: }
1979:
1.16 markus 1980: /*
1981: * Logs the error plus constructs and sends a disconnect packet, closes the
1982: * connection, and exits. This function never returns. The error message
1983: * should not contain a newline. The length of the formatted message must
1984: * not exceed 1024 bytes.
1985: */
1.2 provos 1986: void
1.201 markus 1987: ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1988: {
1.14 markus 1989: char buf[1024];
1990: va_list args;
1991: static int disconnecting = 0;
1.201 markus 1992: int r;
1.97 deraadt 1993:
1.14 markus 1994: if (disconnecting) /* Guard against recursive invocations. */
1995: fatal("packet_disconnect called recursively.");
1996: disconnecting = 1;
1997:
1.16 markus 1998: /*
1999: * Format the message. Note that the caller must make sure the
2000: * message is of limited size.
2001: */
1.14 markus 2002: va_start(args, fmt);
2003: vsnprintf(buf, sizeof(buf), fmt, args);
2004: va_end(args);
2005:
1.99 markus 2006: /* Display the error locally */
1.106 itojun 2007: logit("Disconnecting: %.100s", buf);
1.99 markus 2008:
1.205 djm 2009: /*
2010: * Send the disconnect message to the other side, and wait
2011: * for it to get sent.
2012: */
2013: if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
2014: sshpkt_fatal(ssh, __func__, r);
2015:
2016: if ((r = ssh_packet_write_wait(ssh)) != 0)
2017: sshpkt_fatal(ssh, __func__, r);
1.14 markus 2018:
2019: /* Close the connection. */
1.201 markus 2020: ssh_packet_close(ssh);
1.112 markus 2021: cleanup_exit(255);
1.1 deraadt 2022: }
2023:
1.205 djm 2024: /*
2025: * Checks if there is any buffered output, and tries to write some of
2026: * the output.
2027: */
2028: int
1.201 markus 2029: ssh_packet_write_poll(struct ssh *ssh)
1.1 deraadt 2030: {
1.201 markus 2031: struct session_state *state = ssh->state;
2032: int len = sshbuf_len(state->output);
1.222 markus 2033: int r;
1.97 deraadt 2034:
1.14 markus 2035: if (len > 0) {
1.222 markus 2036: len = write(state->connection_out,
2037: sshbuf_ptr(state->output), len);
1.156 djm 2038: if (len == -1) {
2039: if (errno == EINTR || errno == EAGAIN)
1.205 djm 2040: return 0;
2041: return SSH_ERR_SYSTEM_ERROR;
1.14 markus 2042: }
1.222 markus 2043: if (len == 0)
1.205 djm 2044: return SSH_ERR_CONN_CLOSED;
1.201 markus 2045: if ((r = sshbuf_consume(state->output, len)) != 0)
1.205 djm 2046: return r;
1.14 markus 2047: }
1.205 djm 2048: return 0;
1.1 deraadt 2049: }
2050:
1.16 markus 2051: /*
2052: * Calls packet_write_poll repeatedly until all pending output data has been
2053: * written.
2054: */
1.205 djm 2055: int
1.201 markus 2056: ssh_packet_write_wait(struct ssh *ssh)
1.1 deraadt 2057: {
1.56 millert 2058: fd_set *setp;
1.205 djm 2059: int ret, r, ms_remain = 0;
1.154 dtucker 2060: struct timeval start, timeout, *timeoutp = NULL;
1.201 markus 2061: struct session_state *state = ssh->state;
1.56 millert 2062:
1.214 deraadt 2063: setp = calloc(howmany(state->connection_out + 1,
1.161 andreas 2064: NFDBITS), sizeof(fd_mask));
1.201 markus 2065: if (setp == NULL)
1.205 djm 2066: return SSH_ERR_ALLOC_FAIL;
1.216 gsoares 2067: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2068: free(setp);
1.215 djm 2069: return r;
1.216 gsoares 2070: }
1.201 markus 2071: while (ssh_packet_have_data_to_write(ssh)) {
2072: memset(setp, 0, howmany(state->connection_out + 1,
1.161 andreas 2073: NFDBITS) * sizeof(fd_mask));
1.201 markus 2074: FD_SET(state->connection_out, setp);
1.154 dtucker 2075:
1.201 markus 2076: if (state->packet_timeout_ms > 0) {
2077: ms_remain = state->packet_timeout_ms;
1.154 dtucker 2078: timeoutp = &timeout;
2079: }
2080: for (;;) {
1.201 markus 2081: if (state->packet_timeout_ms != -1) {
1.154 dtucker 2082: ms_to_timeval(&timeout, ms_remain);
2083: gettimeofday(&start, NULL);
2084: }
1.201 markus 2085: if ((ret = select(state->connection_out + 1,
1.161 andreas 2086: NULL, setp, NULL, timeoutp)) >= 0)
1.154 dtucker 2087: break;
1.161 andreas 2088: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 2089: break;
1.201 markus 2090: if (state->packet_timeout_ms == -1)
1.154 dtucker 2091: continue;
2092: ms_subtract_diff(&start, &ms_remain);
2093: if (ms_remain <= 0) {
2094: ret = 0;
2095: break;
2096: }
2097: }
2098: if (ret == 0) {
1.205 djm 2099: free(setp);
2100: return SSH_ERR_CONN_TIMEOUT;
2101: }
2102: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2103: free(setp);
2104: return r;
1.154 dtucker 2105: }
1.14 markus 2106: }
1.186 djm 2107: free(setp);
1.205 djm 2108: return 0;
1.1 deraadt 2109: }
2110:
2111: /* Returns true if there is buffered data to write to the connection. */
2112:
1.2 provos 2113: int
1.201 markus 2114: ssh_packet_have_data_to_write(struct ssh *ssh)
1.1 deraadt 2115: {
1.201 markus 2116: return sshbuf_len(ssh->state->output) != 0;
1.1 deraadt 2117: }
2118:
2119: /* Returns true if there is not too much data to write to the connection. */
2120:
1.2 provos 2121: int
1.201 markus 2122: ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1.1 deraadt 2123: {
1.201 markus 2124: if (ssh->state->interactive_mode)
2125: return sshbuf_len(ssh->state->output) < 16384;
1.14 markus 2126: else
1.201 markus 2127: return sshbuf_len(ssh->state->output) < 128 * 1024;
1.1 deraadt 2128: }
2129:
1.201 markus 2130: void
2131: ssh_packet_set_tos(struct ssh *ssh, int tos)
1.101 markus 2132: {
1.201 markus 2133: if (!ssh_packet_connection_is_on_socket(ssh))
1.101 markus 2134: return;
1.201 markus 2135: switch (ssh_packet_connection_af(ssh)) {
1.173 djm 2136: case AF_INET:
2137: debug3("%s: set IP_TOS 0x%02x", __func__, tos);
1.201 markus 2138: if (setsockopt(ssh->state->connection_in,
1.173 djm 2139: IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2140: error("setsockopt IP_TOS %d: %.100s:",
2141: tos, strerror(errno));
2142: break;
2143: case AF_INET6:
2144: debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
1.201 markus 2145: if (setsockopt(ssh->state->connection_in,
1.173 djm 2146: IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2147: error("setsockopt IPV6_TCLASS %d: %.100s:",
2148: tos, strerror(errno));
2149: break;
2150: }
1.101 markus 2151: }
2152:
1.1 deraadt 2153: /* Informs that the current session is interactive. Sets IP flags for that. */
2154:
1.2 provos 2155: void
1.201 markus 2156: ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
1.1 deraadt 2157: {
1.201 markus 2158: struct session_state *state = ssh->state;
2159:
2160: if (state->set_interactive_called)
1.43 markus 2161: return;
1.201 markus 2162: state->set_interactive_called = 1;
1.1 deraadt 2163:
1.14 markus 2164: /* Record that we are in interactive mode. */
1.201 markus 2165: state->interactive_mode = interactive;
1.1 deraadt 2166:
1.19 markus 2167: /* Only set socket options if using a socket. */
1.201 markus 2168: if (!ssh_packet_connection_is_on_socket(ssh))
1.14 markus 2169: return;
1.201 markus 2170: set_nodelay(state->connection_in);
2171: ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2172: qos_bulk);
1.1 deraadt 2173: }
2174:
2175: /* Returns true if the current connection is interactive. */
2176:
1.2 provos 2177: int
1.201 markus 2178: ssh_packet_is_interactive(struct ssh *ssh)
1.1 deraadt 2179: {
1.201 markus 2180: return ssh->state->interactive_mode;
1.12 markus 2181: }
2182:
1.113 deraadt 2183: int
1.201 markus 2184: ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
1.12 markus 2185: {
1.201 markus 2186: struct session_state *state = ssh->state;
2187:
2188: if (state->set_maxsize_called) {
1.106 itojun 2189: logit("packet_set_maxsize: called twice: old %d new %d",
1.201 markus 2190: state->max_packet_size, s);
1.14 markus 2191: return -1;
2192: }
2193: if (s < 4 * 1024 || s > 1024 * 1024) {
1.106 itojun 2194: logit("packet_set_maxsize: bad size %d", s);
1.14 markus 2195: return -1;
2196: }
1.201 markus 2197: state->set_maxsize_called = 1;
1.66 markus 2198: debug("packet_set_maxsize: setting to %d", s);
1.201 markus 2199: state->max_packet_size = s;
1.14 markus 2200: return s;
1.53 markus 2201: }
2202:
1.161 andreas 2203: int
1.201 markus 2204: ssh_packet_inc_alive_timeouts(struct ssh *ssh)
1.161 andreas 2205: {
1.201 markus 2206: return ++ssh->state->keep_alive_timeouts;
1.161 andreas 2207: }
2208:
2209: void
1.201 markus 2210: ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
1.161 andreas 2211: {
1.201 markus 2212: ssh->state->keep_alive_timeouts = ka;
1.161 andreas 2213: }
2214:
2215: u_int
1.201 markus 2216: ssh_packet_get_maxsize(struct ssh *ssh)
1.71 markus 2217: {
1.201 markus 2218: return ssh->state->max_packet_size;
1.71 markus 2219: }
2220:
1.53 markus 2221: /*
2222: * 9.2. Ignored Data Message
1.61 markus 2223: *
1.53 markus 2224: * byte SSH_MSG_IGNORE
2225: * string data
1.61 markus 2226: *
1.53 markus 2227: * All implementations MUST understand (and ignore) this message at any
2228: * time (after receiving the protocol version). No implementation is
2229: * required to send them. This message can be used as an additional
2230: * protection measure against advanced traffic analysis techniques.
2231: */
1.54 markus 2232: void
1.201 markus 2233: ssh_packet_send_ignore(struct ssh *ssh, int nbytes)
1.54 markus 2234: {
1.115 avsm 2235: u_int32_t rnd = 0;
1.201 markus 2236: int r, i;
1.54 markus 2237:
1.201 markus 2238: if ((r = sshpkt_start(ssh, compat20 ?
2239: SSH2_MSG_IGNORE : SSH_MSG_IGNORE)) != 0 ||
2240: (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2241: fatal("%s: %s", __func__, ssh_err(r));
1.75 deraadt 2242: for (i = 0; i < nbytes; i++) {
1.53 markus 2243: if (i % 4 == 0)
1.115 avsm 2244: rnd = arc4random();
1.201 markus 2245: if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2246: fatal("%s: %s", __func__, ssh_err(r));
1.115 avsm 2247: rnd >>= 8;
1.53 markus 2248: }
1.105 markus 2249: }
2250:
1.113 deraadt 2251: #define MAX_PACKETS (1U<<31)
1.105 markus 2252: int
1.201 markus 2253: ssh_packet_need_rekeying(struct ssh *ssh)
1.105 markus 2254: {
1.201 markus 2255: struct session_state *state = ssh->state;
2256:
2257: if (ssh->compat & SSH_BUG_NOREKEY)
1.105 markus 2258: return 0;
2259: return
1.201 markus 2260: (state->p_send.packets > MAX_PACKETS) ||
2261: (state->p_read.packets > MAX_PACKETS) ||
2262: (state->max_blocks_out &&
1.225 dtucker 2263: (state->p_send.blocks > state->max_blocks_out)) ||
1.201 markus 2264: (state->max_blocks_in &&
1.225 dtucker 2265: (state->p_read.blocks > state->max_blocks_in)) ||
1.201 markus 2266: (state->rekey_interval != 0 && state->rekey_time +
2267: state->rekey_interval <= monotime());
1.105 markus 2268: }
2269:
2270: void
1.224 dtucker 2271: ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, time_t seconds)
1.105 markus 2272: {
1.224 dtucker 2273: debug3("rekey after %llu bytes, %d seconds", (unsigned long long)bytes,
1.184 dtucker 2274: (int)seconds);
1.201 markus 2275: ssh->state->rekey_limit = bytes;
2276: ssh->state->rekey_interval = seconds;
1.184 dtucker 2277: }
2278:
2279: time_t
1.201 markus 2280: ssh_packet_get_rekey_timeout(struct ssh *ssh)
1.184 dtucker 2281: {
2282: time_t seconds;
2283:
1.201 markus 2284: seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
1.187 dtucker 2285: monotime();
1.185 dtucker 2286: return (seconds <= 0 ? 1 : seconds);
1.118 markus 2287: }
2288:
2289: void
1.201 markus 2290: ssh_packet_set_server(struct ssh *ssh)
1.118 markus 2291: {
1.201 markus 2292: ssh->state->server_side = 1;
1.118 markus 2293: }
2294:
2295: void
1.201 markus 2296: ssh_packet_set_authenticated(struct ssh *ssh)
1.118 markus 2297: {
1.201 markus 2298: ssh->state->after_authentication = 1;
1.161 andreas 2299: }
2300:
2301: void *
1.201 markus 2302: ssh_packet_get_input(struct ssh *ssh)
1.161 andreas 2303: {
1.201 markus 2304: return (void *)ssh->state->input;
1.161 andreas 2305: }
2306:
2307: void *
1.201 markus 2308: ssh_packet_get_output(struct ssh *ssh)
1.161 andreas 2309: {
1.201 markus 2310: return (void *)ssh->state->output;
1.166 andreas 2311: }
2312:
1.196 markus 2313: /* Reset after_authentication and reset compression in post-auth privsep */
1.201 markus 2314: static int
2315: ssh_packet_set_postauth(struct ssh *ssh)
1.196 markus 2316: {
1.201 markus 2317: struct sshcomp *comp;
2318: int r, mode;
1.196 markus 2319:
2320: debug("%s: called", __func__);
2321: /* This was set in net child, but is not visible in user child */
1.201 markus 2322: ssh->state->after_authentication = 1;
2323: ssh->state->rekeying = 0;
1.196 markus 2324: for (mode = 0; mode < MODE_MAX; mode++) {
1.201 markus 2325: if (ssh->state->newkeys[mode] == NULL)
1.196 markus 2326: continue;
1.201 markus 2327: comp = &ssh->state->newkeys[mode]->comp;
2328: if (comp && comp->enabled &&
2329: (r = ssh_packet_init_compression(ssh)) != 0)
2330: return r;
2331: }
2332: return 0;
2333: }
2334:
2335: /* Packet state (de-)serialization for privsep */
2336:
2337: /* turn kex into a blob for packet state serialization */
2338: static int
2339: kex_to_blob(struct sshbuf *m, struct kex *kex)
2340: {
2341: int r;
2342:
2343: if ((r = sshbuf_put_string(m, kex->session_id,
2344: kex->session_id_len)) != 0 ||
2345: (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2346: (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2347: (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2348: (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2349: (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2350: (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2351: (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2352: (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2353: return r;
2354: return 0;
2355: }
2356:
2357: /* turn key exchange results into a blob for packet state serialization */
2358: static int
2359: newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2360: {
2361: struct sshbuf *b;
2362: struct sshcipher_ctx *cc;
2363: struct sshcomp *comp;
2364: struct sshenc *enc;
2365: struct sshmac *mac;
2366: struct newkeys *newkey;
2367: int r;
2368:
2369: if ((newkey = ssh->state->newkeys[mode]) == NULL)
2370: return SSH_ERR_INTERNAL_ERROR;
2371: enc = &newkey->enc;
2372: mac = &newkey->mac;
2373: comp = &newkey->comp;
2374: cc = (mode == MODE_OUT) ? &ssh->state->send_context :
2375: &ssh->state->receive_context;
2376: if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2377: return r;
2378: if ((b = sshbuf_new()) == NULL)
2379: return SSH_ERR_ALLOC_FAIL;
2380: /* The cipher struct is constant and shared, you export pointer */
2381: if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2382: (r = sshbuf_put(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2383: (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2384: (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2385: (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2386: (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2387: goto out;
2388: if (cipher_authlen(enc->cipher) == 0) {
2389: if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2390: (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2391: (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2392: goto out;
2393: }
2394: if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2395: (r = sshbuf_put_u32(b, comp->enabled)) != 0 ||
2396: (r = sshbuf_put_cstring(b, comp->name)) != 0)
2397: goto out;
2398: r = sshbuf_put_stringb(m, b);
2399: out:
1.221 mmcc 2400: sshbuf_free(b);
1.201 markus 2401: return r;
2402: }
2403:
2404: /* serialize packet state into a blob */
2405: int
2406: ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2407: {
2408: struct session_state *state = ssh->state;
2409: u_char *p;
2410: size_t slen, rlen;
2411: int r, ssh1cipher;
2412:
2413: if (!compat20) {
2414: ssh1cipher = cipher_get_number(state->receive_context.cipher);
2415: slen = cipher_get_keyiv_len(&state->send_context);
2416: rlen = cipher_get_keyiv_len(&state->receive_context);
2417: if ((r = sshbuf_put_u32(m, state->remote_protocol_flags)) != 0 ||
2418: (r = sshbuf_put_u32(m, ssh1cipher)) != 0 ||
2419: (r = sshbuf_put_string(m, state->ssh1_key, state->ssh1_keylen)) != 0 ||
2420: (r = sshbuf_put_u32(m, slen)) != 0 ||
2421: (r = sshbuf_reserve(m, slen, &p)) != 0 ||
2422: (r = cipher_get_keyiv(&state->send_context, p, slen)) != 0 ||
2423: (r = sshbuf_put_u32(m, rlen)) != 0 ||
2424: (r = sshbuf_reserve(m, rlen, &p)) != 0 ||
2425: (r = cipher_get_keyiv(&state->receive_context, p, rlen)) != 0)
2426: return r;
2427: } else {
2428: if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2429: (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2430: (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
1.224 dtucker 2431: (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
1.208 markus 2432: (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
1.201 markus 2433: (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2434: (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2435: (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2436: (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2437: (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2438: (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2439: (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2440: (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0)
2441: return r;
2442: }
2443:
2444: slen = cipher_get_keycontext(&state->send_context, NULL);
2445: rlen = cipher_get_keycontext(&state->receive_context, NULL);
2446: if ((r = sshbuf_put_u32(m, slen)) != 0 ||
2447: (r = sshbuf_reserve(m, slen, &p)) != 0)
2448: return r;
2449: if (cipher_get_keycontext(&state->send_context, p) != (int)slen)
2450: return SSH_ERR_INTERNAL_ERROR;
2451: if ((r = sshbuf_put_u32(m, rlen)) != 0 ||
2452: (r = sshbuf_reserve(m, rlen, &p)) != 0)
2453: return r;
2454: if (cipher_get_keycontext(&state->receive_context, p) != (int)rlen)
2455: return SSH_ERR_INTERNAL_ERROR;
2456:
2457: if ((r = ssh_packet_get_compress_state(m, ssh)) != 0 ||
2458: (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2459: (r = sshbuf_put_stringb(m, state->output)) != 0)
2460: return r;
2461:
2462: return 0;
2463: }
2464:
2465: /* restore key exchange results from blob for packet state de-serialization */
2466: static int
2467: newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2468: {
2469: struct sshbuf *b = NULL;
2470: struct sshcomp *comp;
2471: struct sshenc *enc;
2472: struct sshmac *mac;
2473: struct newkeys *newkey = NULL;
2474: size_t keylen, ivlen, maclen;
2475: int r;
2476:
2477: if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2478: r = SSH_ERR_ALLOC_FAIL;
2479: goto out;
2480: }
2481: if ((r = sshbuf_froms(m, &b)) != 0)
2482: goto out;
2483: #ifdef DEBUG_PK
2484: sshbuf_dump(b, stderr);
2485: #endif
2486: enc = &newkey->enc;
2487: mac = &newkey->mac;
2488: comp = &newkey->comp;
2489:
2490: if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2491: (r = sshbuf_get(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2492: (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2493: (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2494: (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2495: (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2496: goto out;
2497: if (cipher_authlen(enc->cipher) == 0) {
2498: if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2499: goto out;
2500: if ((r = mac_setup(mac, mac->name)) != 0)
2501: goto out;
2502: if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2503: (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2504: goto out;
2505: if (maclen > mac->key_len) {
2506: r = SSH_ERR_INVALID_FORMAT;
2507: goto out;
2508: }
2509: mac->key_len = maclen;
2510: }
2511: if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2512: (r = sshbuf_get_u32(b, (u_int *)&comp->enabled)) != 0 ||
2513: (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2514: goto out;
2515: if (enc->name == NULL ||
2516: cipher_by_name(enc->name) != enc->cipher) {
2517: r = SSH_ERR_INVALID_FORMAT;
2518: goto out;
2519: }
2520: if (sshbuf_len(b) != 0) {
2521: r = SSH_ERR_INVALID_FORMAT;
2522: goto out;
2523: }
2524: enc->key_len = keylen;
2525: enc->iv_len = ivlen;
2526: ssh->kex->newkeys[mode] = newkey;
2527: newkey = NULL;
2528: r = 0;
2529: out:
1.219 mmcc 2530: free(newkey);
1.221 mmcc 2531: sshbuf_free(b);
1.201 markus 2532: return r;
2533: }
2534:
2535: /* restore kex from blob for packet state de-serialization */
2536: static int
2537: kex_from_blob(struct sshbuf *m, struct kex **kexp)
2538: {
2539: struct kex *kex;
2540: int r;
2541:
2542: if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2543: (kex->my = sshbuf_new()) == NULL ||
2544: (kex->peer = sshbuf_new()) == NULL) {
2545: r = SSH_ERR_ALLOC_FAIL;
2546: goto out;
2547: }
2548: if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2549: (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2550: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2551: (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2552: (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2553: (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2554: (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2555: (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2556: (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2557: goto out;
2558: kex->server = 1;
2559: kex->done = 1;
2560: r = 0;
2561: out:
2562: if (r != 0 || kexp == NULL) {
2563: if (kex != NULL) {
1.221 mmcc 2564: sshbuf_free(kex->my);
2565: sshbuf_free(kex->peer);
1.201 markus 2566: free(kex);
2567: }
2568: if (kexp != NULL)
2569: *kexp = NULL;
2570: } else {
2571: *kexp = kex;
2572: }
2573: return r;
2574: }
2575:
2576: /*
2577: * Restore packet state from content of blob 'm' (de-serialization).
2578: * Note that 'm' will be partially consumed on parsing or any other errors.
2579: */
2580: int
2581: ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2582: {
2583: struct session_state *state = ssh->state;
2584: const u_char *ssh1key, *ivin, *ivout, *keyin, *keyout, *input, *output;
2585: size_t ssh1keylen, rlen, slen, ilen, olen;
2586: int r;
2587: u_int ssh1cipher = 0;
2588:
2589: if (!compat20) {
2590: if ((r = sshbuf_get_u32(m, &state->remote_protocol_flags)) != 0 ||
2591: (r = sshbuf_get_u32(m, &ssh1cipher)) != 0 ||
2592: (r = sshbuf_get_string_direct(m, &ssh1key, &ssh1keylen)) != 0 ||
2593: (r = sshbuf_get_string_direct(m, &ivout, &slen)) != 0 ||
2594: (r = sshbuf_get_string_direct(m, &ivin, &rlen)) != 0)
2595: return r;
2596: if (ssh1cipher > INT_MAX)
2597: return SSH_ERR_KEY_UNKNOWN_CIPHER;
2598: ssh_packet_set_encryption_key(ssh, ssh1key, ssh1keylen,
2599: (int)ssh1cipher);
2600: if (cipher_get_keyiv_len(&state->send_context) != (int)slen ||
2601: cipher_get_keyiv_len(&state->receive_context) != (int)rlen)
2602: return SSH_ERR_INVALID_FORMAT;
2603: if ((r = cipher_set_keyiv(&state->send_context, ivout)) != 0 ||
2604: (r = cipher_set_keyiv(&state->receive_context, ivin)) != 0)
2605: return r;
2606: } else {
2607: if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2608: (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2609: (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
1.224 dtucker 2610: (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
1.208 markus 2611: (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
1.201 markus 2612: (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2613: (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2614: (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2615: (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2616: (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2617: (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2618: (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2619: (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2620: return r;
1.208 markus 2621: /*
2622: * We set the time here so that in post-auth privsep slave we
2623: * count from the completion of the authentication.
2624: */
2625: state->rekey_time = monotime();
1.201 markus 2626: /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2627: if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2628: (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2629: return r;
2630: }
2631: if ((r = sshbuf_get_string_direct(m, &keyout, &slen)) != 0 ||
2632: (r = sshbuf_get_string_direct(m, &keyin, &rlen)) != 0)
2633: return r;
2634: if (cipher_get_keycontext(&state->send_context, NULL) != (int)slen ||
2635: cipher_get_keycontext(&state->receive_context, NULL) != (int)rlen)
2636: return SSH_ERR_INVALID_FORMAT;
2637: cipher_set_keycontext(&state->send_context, keyout);
2638: cipher_set_keycontext(&state->receive_context, keyin);
2639:
2640: if ((r = ssh_packet_set_compress_state(ssh, m)) != 0 ||
2641: (r = ssh_packet_set_postauth(ssh)) != 0)
2642: return r;
2643:
2644: sshbuf_reset(state->input);
2645: sshbuf_reset(state->output);
2646: if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2647: (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2648: (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2649: (r = sshbuf_put(state->output, output, olen)) != 0)
2650: return r;
2651:
2652: if (sshbuf_len(m))
2653: return SSH_ERR_INVALID_FORMAT;
2654: debug3("%s: done", __func__);
2655: return 0;
2656: }
2657:
2658: /* NEW API */
2659:
2660: /* put data to the outgoing packet */
2661:
2662: int
2663: sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2664: {
2665: return sshbuf_put(ssh->state->outgoing_packet, v, len);
2666: }
2667:
2668: int
2669: sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2670: {
2671: return sshbuf_putb(ssh->state->outgoing_packet, b);
2672: }
2673:
2674: int
2675: sshpkt_put_u8(struct ssh *ssh, u_char val)
2676: {
2677: return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2678: }
2679:
2680: int
2681: sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2682: {
2683: return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2684: }
2685:
2686: int
2687: sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2688: {
2689: return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2690: }
2691:
2692: int
2693: sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2694: {
2695: return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2696: }
2697:
2698: int
2699: sshpkt_put_cstring(struct ssh *ssh, const void *v)
2700: {
2701: return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2702: }
2703:
2704: int
2705: sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2706: {
2707: return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2708: }
2709:
1.211 djm 2710: #ifdef WITH_OPENSSL
1.201 markus 2711: int
2712: sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2713: {
2714: return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2715: }
2716:
1.211 djm 2717: #ifdef WITH_SSH1
1.201 markus 2718: int
2719: sshpkt_put_bignum1(struct ssh *ssh, const BIGNUM *v)
2720: {
2721: return sshbuf_put_bignum1(ssh->state->outgoing_packet, v);
2722: }
1.211 djm 2723: #endif /* WITH_SSH1 */
1.201 markus 2724:
2725: int
2726: sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2727: {
2728: return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2729: }
1.211 djm 2730: #endif /* WITH_OPENSSL */
1.201 markus 2731:
2732: /* fetch data from the incoming packet */
2733:
2734: int
2735: sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2736: {
2737: return sshbuf_get(ssh->state->incoming_packet, valp, len);
2738: }
2739:
2740: int
2741: sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2742: {
2743: return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2744: }
2745:
2746: int
2747: sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2748: {
2749: return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2750: }
2751:
2752: int
2753: sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2754: {
2755: return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2756: }
2757:
2758: int
2759: sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2760: {
2761: return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2762: }
2763:
2764: int
2765: sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2766: {
2767: return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2768: }
2769:
2770: int
2771: sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2772: {
2773: return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2774: }
2775:
1.211 djm 2776: #ifdef WITH_OPENSSL
1.201 markus 2777: int
2778: sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2779: {
2780: return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2781: }
2782:
1.211 djm 2783: #ifdef WITH_SSH1
1.201 markus 2784: int
2785: sshpkt_get_bignum1(struct ssh *ssh, BIGNUM *v)
2786: {
2787: return sshbuf_get_bignum1(ssh->state->incoming_packet, v);
2788: }
1.211 djm 2789: #endif /* WITH_SSH1 */
1.201 markus 2790:
2791: int
2792: sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2793: {
2794: return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2795: }
1.211 djm 2796: #endif /* WITH_OPENSSL */
1.201 markus 2797:
2798: int
2799: sshpkt_get_end(struct ssh *ssh)
2800: {
2801: if (sshbuf_len(ssh->state->incoming_packet) > 0)
2802: return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2803: return 0;
2804: }
2805:
2806: const u_char *
2807: sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2808: {
2809: if (lenp != NULL)
2810: *lenp = sshbuf_len(ssh->state->incoming_packet);
2811: return sshbuf_ptr(ssh->state->incoming_packet);
2812: }
2813:
2814: /* start a new packet */
2815:
2816: int
2817: sshpkt_start(struct ssh *ssh, u_char type)
2818: {
2819: u_char buf[9];
2820: int len;
2821:
2822: DBG(debug("packet_start[%d]", type));
2823: len = compat20 ? 6 : 9;
2824: memset(buf, 0, len - 1);
2825: buf[len - 1] = type;
2826: sshbuf_reset(ssh->state->outgoing_packet);
2827: return sshbuf_put(ssh->state->outgoing_packet, buf, len);
2828: }
2829:
2830: /* send it */
2831:
2832: int
2833: sshpkt_send(struct ssh *ssh)
2834: {
2835: if (compat20)
2836: return ssh_packet_send2(ssh);
2837: else
2838: return ssh_packet_send1(ssh);
2839: }
2840:
2841: int
2842: sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2843: {
2844: char buf[1024];
2845: va_list args;
2846: int r;
2847:
2848: va_start(args, fmt);
2849: vsnprintf(buf, sizeof(buf), fmt, args);
2850: va_end(args);
2851:
2852: if (compat20) {
2853: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2854: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2855: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2856: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2857: (r = sshpkt_send(ssh)) != 0)
2858: return r;
2859: } else {
2860: if ((r = sshpkt_start(ssh, SSH_MSG_DISCONNECT)) != 0 ||
2861: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2862: (r = sshpkt_send(ssh)) != 0)
2863: return r;
1.166 andreas 2864: }
1.201 markus 2865: return 0;
2866: }
2867:
2868: /* roundup current message to pad bytes */
2869: int
2870: sshpkt_add_padding(struct ssh *ssh, u_char pad)
2871: {
2872: ssh->state->extra_pad = pad;
2873: return 0;
1.1 deraadt 2874: }
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