Annotation of src/usr.bin/ssh/packet.c, Revision 1.225
1.225 ! dtucker 1: /* $OpenBSD: packet.c,v 1.222 2016/01/14 16:17:40 markus Exp $ */
1.1 deraadt 2: /*
1.15 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.35 deraadt 6: * This file contains code implementing the packet protocol and communication
7: * with the other side. This same code is used both on client and server side.
1.29 markus 8: *
1.35 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
1.29 markus 14: *
1.25 markus 15: *
16: * SSH2 packet format added by Markus Friedl.
1.69 markus 17: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.25 markus 18: *
1.35 deraadt 19: * Redistribution and use in source and binary forms, with or without
20: * modification, are permitted provided that the following conditions
21: * are met:
22: * 1. Redistributions of source code must retain the above copyright
23: * notice, this list of conditions and the following disclaimer.
24: * 2. Redistributions in binary form must reproduce the above copyright
25: * notice, this list of conditions and the following disclaimer in the
26: * documentation and/or other materials provided with the distribution.
27: *
28: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
29: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
30: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
31: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
32: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
33: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
37: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.15 deraadt 38: */
1.1 deraadt 39:
1.203 deraadt 40: #include <sys/param.h> /* MIN roundup */
1.142 deraadt 41: #include <sys/types.h>
1.105 markus 42: #include <sys/queue.h>
1.132 stevesk 43: #include <sys/socket.h>
1.138 stevesk 44: #include <sys/time.h>
1.132 stevesk 45: #include <netinet/in.h>
1.121 stevesk 46: #include <netinet/ip.h>
1.134 stevesk 47:
1.135 stevesk 48: #include <errno.h>
1.134 stevesk 49: #include <stdarg.h>
1.141 stevesk 50: #include <stdio.h>
1.140 stevesk 51: #include <stdlib.h>
1.137 stevesk 52: #include <string.h>
1.136 stevesk 53: #include <unistd.h>
1.203 deraadt 54: #include <limits.h>
1.142 deraadt 55: #include <signal.h>
1.184 dtucker 56: #include <time.h>
1.1 deraadt 57:
1.201 markus 58: #include <zlib.h>
59:
60: #include "buffer.h" /* typedefs XXX */
61: #include "key.h" /* typedefs XXX */
62:
1.1 deraadt 63: #include "xmalloc.h"
64: #include "crc32.h"
1.9 dugsong 65: #include "deattack.h"
1.25 markus 66: #include "compat.h"
1.45 markus 67: #include "ssh1.h"
1.25 markus 68: #include "ssh2.h"
1.37 markus 69: #include "cipher.h"
1.201 markus 70: #include "sshkey.h"
1.25 markus 71: #include "kex.h"
1.200 markus 72: #include "digest.h"
1.50 markus 73: #include "mac.h"
1.46 markus 74: #include "log.h"
75: #include "canohost.h"
1.87 stevesk 76: #include "misc.h"
1.198 millert 77: #include "channels.h"
1.95 markus 78: #include "ssh.h"
1.201 markus 79: #include "packet.h"
1.197 djm 80: #include "ssherr.h"
1.201 markus 81: #include "sshbuf.h"
1.25 markus 82:
83: #ifdef PACKET_DEBUG
84: #define DBG(x) x
85: #else
86: #define DBG(x)
87: #endif
88:
1.159 markus 89: #define PACKET_MAX_SIZE (256 * 1024)
90:
1.161 andreas 91: struct packet_state {
92: u_int32_t seqnr;
93: u_int32_t packets;
94: u_int64_t blocks;
95: u_int64_t bytes;
96: };
97:
98: struct packet {
99: TAILQ_ENTRY(packet) next;
100: u_char type;
1.201 markus 101: struct sshbuf *payload;
1.161 andreas 102: };
103:
104: struct session_state {
105: /*
106: * This variable contains the file descriptors used for
107: * communicating with the other side. connection_in is used for
108: * reading; connection_out for writing. These can be the same
109: * descriptor, in which case it is assumed to be a socket.
110: */
111: int connection_in;
112: int connection_out;
113:
114: /* Protocol flags for the remote side. */
115: u_int remote_protocol_flags;
1.1 deraadt 116:
1.161 andreas 117: /* Encryption context for receiving data. Only used for decryption. */
1.201 markus 118: struct sshcipher_ctx receive_context;
1.1 deraadt 119:
1.161 andreas 120: /* Encryption context for sending data. Only used for encryption. */
1.201 markus 121: struct sshcipher_ctx send_context;
1.14 markus 122:
1.161 andreas 123: /* Buffer for raw input data from the socket. */
1.201 markus 124: struct sshbuf *input;
1.1 deraadt 125:
1.161 andreas 126: /* Buffer for raw output data going to the socket. */
1.201 markus 127: struct sshbuf *output;
1.1 deraadt 128:
1.161 andreas 129: /* Buffer for the partial outgoing packet being constructed. */
1.201 markus 130: struct sshbuf *outgoing_packet;
1.1 deraadt 131:
1.161 andreas 132: /* Buffer for the incoming packet currently being processed. */
1.201 markus 133: struct sshbuf *incoming_packet;
1.1 deraadt 134:
1.161 andreas 135: /* Scratch buffer for packet compression/decompression. */
1.201 markus 136: struct sshbuf *compression_buffer;
137:
138: /* Incoming/outgoing compression dictionaries */
139: z_stream compression_in_stream;
140: z_stream compression_out_stream;
141: int compression_in_started;
142: int compression_out_started;
143: int compression_in_failures;
144: int compression_out_failures;
1.1 deraadt 145:
1.161 andreas 146: /*
147: * Flag indicating whether packet compression/decompression is
148: * enabled.
149: */
150: int packet_compression;
1.1 deraadt 151:
1.161 andreas 152: /* default maximum packet size */
153: u_int max_packet_size;
1.1 deraadt 154:
1.161 andreas 155: /* Flag indicating whether this module has been initialized. */
156: int initialized;
1.12 markus 157:
1.161 andreas 158: /* Set to true if the connection is interactive. */
159: int interactive_mode;
1.1 deraadt 160:
1.161 andreas 161: /* Set to true if we are the server side. */
162: int server_side;
1.1 deraadt 163:
1.161 andreas 164: /* Set to true if we are authenticated. */
165: int after_authentication;
1.118 markus 166:
1.161 andreas 167: int keep_alive_timeouts;
1.118 markus 168:
1.161 andreas 169: /* The maximum time that we will wait to send or receive a packet */
170: int packet_timeout_ms;
1.151 dtucker 171:
1.161 andreas 172: /* Session key information for Encryption and MAC */
1.201 markus 173: struct newkeys *newkeys[MODE_MAX];
1.161 andreas 174: struct packet_state p_read, p_send;
1.154 dtucker 175:
1.184 dtucker 176: /* Volume-based rekeying */
1.224 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",
946: state->p_read.bytes, state->p_read.blocks,
947: state->p_send.bytes, state->p_send.blocks);
1.201 markus 948: if ((r = cipher_cleanup(cc)) != 0)
949: return r;
950: enc = &state->newkeys[mode]->enc;
951: mac = &state->newkeys[mode]->mac;
952: comp = &state->newkeys[mode]->comp;
1.148 pvalchev 953: mac_clear(mac);
1.192 djm 954: explicit_bzero(enc->iv, enc->iv_len);
955: explicit_bzero(enc->key, enc->key_len);
956: explicit_bzero(mac->key, mac->key_len);
1.186 djm 957: free(enc->name);
958: free(enc->iv);
959: free(enc->key);
960: free(mac->name);
961: free(mac->key);
962: free(comp->name);
1.201 markus 963: free(state->newkeys[mode]);
1.57 markus 964: }
1.201 markus 965: /* move newkeys from kex to state */
966: if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
967: return SSH_ERR_INTERNAL_ERROR;
968: ssh->kex->newkeys[mode] = NULL;
969: enc = &state->newkeys[mode]->enc;
970: mac = &state->newkeys[mode]->mac;
971: comp = &state->newkeys[mode]->comp;
972: if (cipher_authlen(enc->cipher) == 0) {
973: if ((r = mac_init(mac)) != 0)
974: return r;
975: }
976: mac->enabled = 1;
1.57 markus 977: DBG(debug("cipher_init_context: %d", mode));
1.197 djm 978: if ((r = cipher_init(cc, enc->cipher, enc->key, enc->key_len,
979: enc->iv, enc->iv_len, crypt_type)) != 0)
1.201 markus 980: return r;
981: if (!state->cipher_warning_done &&
982: (wmsg = cipher_warning_message(cc)) != NULL) {
983: error("Warning: %s", wmsg);
984: state->cipher_warning_done = 1;
985: }
1.91 markus 986: /* Deleting the keys does not gain extra security */
1.192 djm 987: /* explicit_bzero(enc->iv, enc->block_size);
988: explicit_bzero(enc->key, enc->key_len);
989: explicit_bzero(mac->key, mac->key_len); */
1.118 markus 990: if ((comp->type == COMP_ZLIB ||
1.161 andreas 991: (comp->type == COMP_DELAYED &&
1.201 markus 992: state->after_authentication)) && comp->enabled == 0) {
993: if ((r = ssh_packet_init_compression(ssh)) < 0)
994: return r;
995: if (mode == MODE_OUT) {
996: if ((r = start_compression_out(ssh, 6)) != 0)
997: return r;
998: } else {
999: if ((r = start_compression_in(ssh)) != 0)
1000: return r;
1001: }
1.57 markus 1002: comp->enabled = 1;
1003: }
1.109 markus 1004: /*
1005: * The 2^(blocksize*2) limit is too expensive for 3DES,
1006: * blowfish, etc, so enforce a 1GB limit for small blocksizes.
1007: */
1008: if (enc->block_size >= 16)
1009: *max_blocks = (u_int64_t)1 << (enc->block_size*2);
1010: else
1011: *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1.201 markus 1012: if (state->rekey_limit)
1.161 andreas 1013: *max_blocks = MIN(*max_blocks,
1.201 markus 1014: state->rekey_limit / enc->block_size);
1.224 dtucker 1015: debug("rekey after %llu blocks", *max_blocks);
1.201 markus 1016: return 0;
1.57 markus 1017: }
1018:
1.16 markus 1019: /*
1.118 markus 1020: * Delayed compression for SSH2 is enabled after authentication:
1.143 dtucker 1021: * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1.118 markus 1022: * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
1023: */
1.201 markus 1024: static int
1025: ssh_packet_enable_delayed_compress(struct ssh *ssh)
1.118 markus 1026: {
1.201 markus 1027: struct session_state *state = ssh->state;
1028: struct sshcomp *comp = NULL;
1029: int r, mode;
1.118 markus 1030:
1031: /*
1032: * Remember that we are past the authentication step, so rekeying
1033: * with COMP_DELAYED will turn on compression immediately.
1034: */
1.201 markus 1035: state->after_authentication = 1;
1.118 markus 1036: for (mode = 0; mode < MODE_MAX; mode++) {
1.145 markus 1037: /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1.201 markus 1038: if (state->newkeys[mode] == NULL)
1.145 markus 1039: continue;
1.201 markus 1040: comp = &state->newkeys[mode]->comp;
1.118 markus 1041: if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1.201 markus 1042: if ((r = ssh_packet_init_compression(ssh)) != 0)
1043: return r;
1044: if (mode == MODE_OUT) {
1045: if ((r = start_compression_out(ssh, 6)) != 0)
1046: return r;
1047: } else {
1048: if ((r = start_compression_in(ssh)) != 0)
1049: return r;
1050: }
1.118 markus 1051: comp->enabled = 1;
1052: }
1053: }
1.201 markus 1054: return 0;
1.118 markus 1055: }
1056:
1057: /*
1.25 markus 1058: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1059: */
1.201 markus 1060: int
1061: ssh_packet_send2_wrapped(struct ssh *ssh)
1.25 markus 1062: {
1.201 markus 1063: struct session_state *state = ssh->state;
1.200 markus 1064: u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1.178 markus 1065: u_char padlen, pad = 0;
1.201 markus 1066: u_int authlen = 0, aadlen = 0;
1067: u_int len;
1068: struct sshenc *enc = NULL;
1069: struct sshmac *mac = NULL;
1070: struct sshcomp *comp = NULL;
1071: int r, block_size;
1072:
1073: if (state->newkeys[MODE_OUT] != NULL) {
1074: enc = &state->newkeys[MODE_OUT]->enc;
1075: mac = &state->newkeys[MODE_OUT]->mac;
1076: comp = &state->newkeys[MODE_OUT]->comp;
1.180 markus 1077: /* disable mac for authenticated encryption */
1078: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1079: mac = NULL;
1.25 markus 1080: }
1.88 markus 1081: block_size = enc ? enc->block_size : 8;
1.180 markus 1082: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1083:
1.201 markus 1084: type = (sshbuf_ptr(state->outgoing_packet))[5];
1.25 markus 1085:
1086: #ifdef PACKET_DEBUG
1087: fprintf(stderr, "plain: ");
1.201 markus 1088: sshbuf_dump(state->outgoing_packet, stderr);
1.25 markus 1089: #endif
1090:
1091: if (comp && comp->enabled) {
1.201 markus 1092: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1093: /* skip header, compress only payload */
1.201 markus 1094: if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1095: goto out;
1096: sshbuf_reset(state->compression_buffer);
1097: if ((r = compress_buffer(ssh, state->outgoing_packet,
1098: state->compression_buffer)) != 0)
1099: goto out;
1100: sshbuf_reset(state->outgoing_packet);
1101: if ((r = sshbuf_put(state->outgoing_packet,
1102: "\0\0\0\0\0", 5)) != 0 ||
1103: (r = sshbuf_putb(state->outgoing_packet,
1104: state->compression_buffer)) != 0)
1105: goto out;
1106: DBG(debug("compression: raw %d compressed %zd", len,
1107: sshbuf_len(state->outgoing_packet)));
1.25 markus 1108: }
1109:
1110: /* sizeof (packet_len + pad_len + payload) */
1.201 markus 1111: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1112:
1113: /*
1114: * calc size of padding, alloc space, get random data,
1115: * minimum padding is 4 bytes
1116: */
1.178 markus 1117: len -= aadlen; /* packet length is not encrypted for EtM modes */
1.25 markus 1118: padlen = block_size - (len % block_size);
1119: if (padlen < 4)
1120: padlen += block_size;
1.201 markus 1121: if (state->extra_pad) {
1.71 markus 1122: /* will wrap if extra_pad+padlen > 255 */
1.201 markus 1123: state->extra_pad =
1124: roundup(state->extra_pad, block_size);
1125: pad = state->extra_pad -
1126: ((len + padlen) % state->extra_pad);
1.193 djm 1127: DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1.201 markus 1128: __func__, pad, len, padlen, state->extra_pad));
1.71 markus 1129: padlen += pad;
1.201 markus 1130: state->extra_pad = 0;
1.71 markus 1131: }
1.201 markus 1132: if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1133: goto out;
1134: if (enc && !state->send_context.plaintext) {
1.32 markus 1135: /* random padding */
1.201 markus 1136: arc4random_buf(cp, padlen);
1.32 markus 1137: } else {
1138: /* clear padding */
1.192 djm 1139: explicit_bzero(cp, padlen);
1.25 markus 1140: }
1.178 markus 1141: /* sizeof (packet_len + pad_len + payload + padding) */
1.201 markus 1142: len = sshbuf_len(state->outgoing_packet);
1143: cp = sshbuf_mutable_ptr(state->outgoing_packet);
1144: if (cp == NULL) {
1145: r = SSH_ERR_INTERNAL_ERROR;
1146: goto out;
1147: }
1.25 markus 1148: /* packet_length includes payload, padding and padding length field */
1.201 markus 1149: POKE_U32(cp, len - 4);
1.89 markus 1150: cp[4] = padlen;
1.178 markus 1151: DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1152: len, padlen, aadlen));
1.25 markus 1153:
1154: /* compute MAC over seqnr and packet(length fields, payload, padding) */
1.178 markus 1155: if (mac && mac->enabled && !mac->etm) {
1.201 markus 1156: if ((r = mac_compute(mac, state->p_send.seqnr,
1157: sshbuf_ptr(state->outgoing_packet), len,
1.200 markus 1158: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1159: goto out;
1160: DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1.25 markus 1161: }
1162: /* encrypt packet and append to output buffer. */
1.201 markus 1163: if ((r = sshbuf_reserve(state->output,
1164: sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1165: goto out;
1166: if ((r = cipher_crypt(&state->send_context, state->p_send.seqnr, cp,
1167: sshbuf_ptr(state->outgoing_packet),
1168: len - aadlen, aadlen, authlen)) != 0)
1169: goto out;
1.25 markus 1170: /* append unencrypted MAC */
1.178 markus 1171: if (mac && mac->enabled) {
1172: if (mac->etm) {
1173: /* EtM: compute mac over aadlen + cipher text */
1.201 markus 1174: if ((r = mac_compute(mac, state->p_send.seqnr,
1175: cp, len, macbuf, sizeof(macbuf))) != 0)
1176: goto out;
1.178 markus 1177: DBG(debug("done calc MAC(EtM) out #%d",
1.201 markus 1178: state->p_send.seqnr));
1.178 markus 1179: }
1.201 markus 1180: if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1181: goto out;
1.178 markus 1182: }
1.25 markus 1183: #ifdef PACKET_DEBUG
1184: fprintf(stderr, "encrypted: ");
1.201 markus 1185: sshbuf_dump(state->output, stderr);
1.25 markus 1186: #endif
1.29 markus 1187: /* increment sequence number for outgoing packets */
1.201 markus 1188: if (++state->p_send.seqnr == 0)
1.106 itojun 1189: logit("outgoing seqnr wraps around");
1.201 markus 1190: if (++state->p_send.packets == 0)
1191: if (!(ssh->compat & SSH_BUG_NOREKEY))
1192: return SSH_ERR_NEED_REKEY;
1193: state->p_send.blocks += len / block_size;
1194: state->p_send.bytes += len;
1195: sshbuf_reset(state->outgoing_packet);
1.25 markus 1196:
1.57 markus 1197: if (type == SSH2_MSG_NEWKEYS)
1.201 markus 1198: r = ssh_set_newkeys(ssh, MODE_OUT);
1199: else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1200: r = ssh_packet_enable_delayed_compress(ssh);
1201: else
1202: r = 0;
1203: out:
1204: return r;
1.25 markus 1205: }
1206:
1.201 markus 1207: int
1208: ssh_packet_send2(struct ssh *ssh)
1.105 markus 1209: {
1.201 markus 1210: struct session_state *state = ssh->state;
1.105 markus 1211: struct packet *p;
1.201 markus 1212: u_char type;
1213: int r;
1.105 markus 1214:
1.201 markus 1215: type = sshbuf_ptr(state->outgoing_packet)[5];
1.105 markus 1216:
1217: /* during rekeying we can only send key exchange messages */
1.201 markus 1218: if (state->rekeying) {
1.175 markus 1219: if ((type < SSH2_MSG_TRANSPORT_MIN) ||
1220: (type > SSH2_MSG_TRANSPORT_MAX) ||
1221: (type == SSH2_MSG_SERVICE_REQUEST) ||
1.218 markus 1222: (type == SSH2_MSG_SERVICE_ACCEPT) ||
1223: (type == SSH2_MSG_EXT_INFO)) {
1.105 markus 1224: debug("enqueue packet: %u", type);
1.201 markus 1225: p = calloc(1, sizeof(*p));
1226: if (p == NULL)
1227: return SSH_ERR_ALLOC_FAIL;
1.105 markus 1228: p->type = type;
1.201 markus 1229: p->payload = state->outgoing_packet;
1230: TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1231: state->outgoing_packet = sshbuf_new();
1232: if (state->outgoing_packet == NULL)
1233: return SSH_ERR_ALLOC_FAIL;
1234: return 0;
1.105 markus 1235: }
1236: }
1237:
1238: /* rekeying starts with sending KEXINIT */
1239: if (type == SSH2_MSG_KEXINIT)
1.201 markus 1240: state->rekeying = 1;
1.105 markus 1241:
1.201 markus 1242: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1243: return r;
1.105 markus 1244:
1245: /* after a NEWKEYS message we can send the complete queue */
1246: if (type == SSH2_MSG_NEWKEYS) {
1.201 markus 1247: state->rekeying = 0;
1248: state->rekey_time = monotime();
1249: while ((p = TAILQ_FIRST(&state->outgoing))) {
1.105 markus 1250: type = p->type;
1251: debug("dequeue packet: %u", type);
1.201 markus 1252: sshbuf_free(state->outgoing_packet);
1253: state->outgoing_packet = p->payload;
1254: TAILQ_REMOVE(&state->outgoing, p, next);
1.186 djm 1255: free(p);
1.201 markus 1256: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1257: return r;
1.105 markus 1258: }
1259: }
1.201 markus 1260: return 0;
1.25 markus 1261: }
1262:
1263: /*
1.16 markus 1264: * Waits until a packet has been received, and returns its type. Note that
1265: * no other data is processed until this returns, so this function should not
1266: * be used during the interactive session.
1267: */
1.1 deraadt 1268:
1.2 provos 1269: int
1.201 markus 1270: ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.1 deraadt 1271: {
1.201 markus 1272: struct session_state *state = ssh->state;
1.222 markus 1273: int len, r, ms_remain;
1.56 millert 1274: fd_set *setp;
1.14 markus 1275: char buf[8192];
1.155 deraadt 1276: struct timeval timeout, start, *timeoutp = NULL;
1277:
1.25 markus 1278: DBG(debug("packet_read()"));
1.14 markus 1279:
1.214 deraadt 1280: setp = calloc(howmany(state->connection_in + 1,
1.161 andreas 1281: NFDBITS), sizeof(fd_mask));
1.201 markus 1282: if (setp == NULL)
1283: return SSH_ERR_ALLOC_FAIL;
1.56 millert 1284:
1.205 djm 1285: /*
1286: * Since we are blocking, ensure that all written packets have
1287: * been sent.
1288: */
1.210 markus 1289: if ((r = ssh_packet_write_wait(ssh)) != 0)
1290: goto out;
1.14 markus 1291:
1292: /* Stay in the loop until we have received a complete packet. */
1293: for (;;) {
1294: /* Try to read a packet from the buffer. */
1.201 markus 1295: r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1296: if (r != 0)
1297: break;
1.62 markus 1298: if (!compat20 && (
1.201 markus 1299: *typep == SSH_SMSG_SUCCESS
1300: || *typep == SSH_SMSG_FAILURE
1301: || *typep == SSH_CMSG_EOF
1302: || *typep == SSH_CMSG_EXIT_CONFIRMATION))
1303: if ((r = sshpkt_get_end(ssh)) != 0)
1304: break;
1.14 markus 1305: /* If we got a packet, return it. */
1.201 markus 1306: if (*typep != SSH_MSG_NONE)
1307: break;
1.16 markus 1308: /*
1309: * Otherwise, wait for some data to arrive, add it to the
1310: * buffer, and try again.
1311: */
1.201 markus 1312: memset(setp, 0, howmany(state->connection_in + 1,
1.161 andreas 1313: NFDBITS) * sizeof(fd_mask));
1.201 markus 1314: FD_SET(state->connection_in, setp);
1.16 markus 1315:
1.201 markus 1316: if (state->packet_timeout_ms > 0) {
1317: ms_remain = state->packet_timeout_ms;
1.154 dtucker 1318: timeoutp = &timeout;
1319: }
1.14 markus 1320: /* Wait for some data to arrive. */
1.154 dtucker 1321: for (;;) {
1.201 markus 1322: if (state->packet_timeout_ms != -1) {
1.154 dtucker 1323: ms_to_timeval(&timeout, ms_remain);
1324: gettimeofday(&start, NULL);
1325: }
1.201 markus 1326: if ((r = select(state->connection_in + 1, setp,
1.161 andreas 1327: NULL, NULL, timeoutp)) >= 0)
1.154 dtucker 1328: break;
1.161 andreas 1329: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 1330: break;
1.201 markus 1331: if (state->packet_timeout_ms == -1)
1.154 dtucker 1332: continue;
1333: ms_subtract_diff(&start, &ms_remain);
1334: if (ms_remain <= 0) {
1.201 markus 1335: r = 0;
1.154 dtucker 1336: break;
1337: }
1338: }
1.204 djm 1339: if (r == 0)
1340: return SSH_ERR_CONN_TIMEOUT;
1.14 markus 1341: /* Read data from the socket. */
1.222 markus 1342: len = read(state->connection_in, buf, sizeof(buf));
1.210 markus 1343: if (len == 0) {
1344: r = SSH_ERR_CONN_CLOSED;
1345: goto out;
1346: }
1347: if (len < 0) {
1348: r = SSH_ERR_SYSTEM_ERROR;
1349: goto out;
1350: }
1.204 djm 1351:
1.14 markus 1352: /* Append it to the buffer. */
1.204 djm 1353: if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1.210 markus 1354: goto out;
1.14 markus 1355: }
1.210 markus 1356: out:
1.201 markus 1357: free(setp);
1358: return r;
1.1 deraadt 1359: }
1360:
1.77 djm 1361: int
1.201 markus 1362: ssh_packet_read(struct ssh *ssh)
1.77 djm 1363: {
1.201 markus 1364: u_char type;
1365: int r;
1366:
1367: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1368: fatal("%s: %s", __func__, ssh_err(r));
1369: return type;
1.77 djm 1370: }
1371:
1.16 markus 1372: /*
1373: * Waits until a packet has been received, verifies that its type matches
1374: * that given, and gives a fatal error and exits if there is a mismatch.
1375: */
1.1 deraadt 1376:
1.205 djm 1377: int
1378: ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1.1 deraadt 1379: {
1.205 djm 1380: int r;
1381: u_char type;
1.1 deraadt 1382:
1.205 djm 1383: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1384: return r;
1385: if (type != expected_type) {
1386: if ((r = sshpkt_disconnect(ssh,
1.201 markus 1387: "Protocol error: expected packet type %d, got %d",
1.205 djm 1388: expected_type, type)) != 0)
1389: return r;
1390: return SSH_ERR_PROTOCOL_ERROR;
1391: }
1392: return 0;
1.1 deraadt 1393: }
1394:
1395: /* Checks if a full packet is available in the data received so far via
1.14 markus 1396: * packet_process_incoming. If so, reads the packet; otherwise returns
1397: * SSH_MSG_NONE. This does not wait for data from the connection.
1398: *
1.150 dtucker 1399: * SSH_MSG_DISCONNECT is handled specially here. Also,
1400: * SSH_MSG_IGNORE messages are skipped by this function and are never returned
1401: * to higher levels.
1.14 markus 1402: */
1.1 deraadt 1403:
1.201 markus 1404: int
1405: ssh_packet_read_poll1(struct ssh *ssh, u_char *typep)
1.1 deraadt 1406: {
1.201 markus 1407: struct session_state *state = ssh->state;
1.40 markus 1408: u_int len, padded_len;
1.205 djm 1409: const char *emsg;
1.201 markus 1410: const u_char *cp;
1411: u_char *p;
1.40 markus 1412: u_int checksum, stored_checksum;
1.201 markus 1413: int r;
1414:
1415: *typep = SSH_MSG_NONE;
1.14 markus 1416:
1417: /* Check if input size is less than minimum packet size. */
1.201 markus 1418: if (sshbuf_len(state->input) < 4 + 8)
1419: return 0;
1.14 markus 1420: /* Get length of incoming packet. */
1.201 markus 1421: len = PEEK_U32(sshbuf_ptr(state->input));
1.205 djm 1422: if (len < 1 + 2 + 2 || len > 256 * 1024) {
1423: if ((r = sshpkt_disconnect(ssh, "Bad packet length %u",
1424: len)) != 0)
1425: return r;
1426: return SSH_ERR_CONN_CORRUPT;
1427: }
1.14 markus 1428: padded_len = (len + 8) & ~7;
1429:
1430: /* Check if the packet has been entirely received. */
1.201 markus 1431: if (sshbuf_len(state->input) < 4 + padded_len)
1432: return 0;
1.14 markus 1433:
1434: /* The entire packet is in buffer. */
1435:
1436: /* Consume packet length. */
1.201 markus 1437: if ((r = sshbuf_consume(state->input, 4)) != 0)
1438: goto out;
1.14 markus 1439:
1.62 markus 1440: /*
1441: * Cryptographic attack detector for ssh
1442: * (C)1998 CORE-SDI, Buenos Aires Argentina
1443: * Ariel Futoransky(futo@core-sdi.com)
1444: */
1.201 markus 1445: if (!state->receive_context.plaintext) {
1.205 djm 1446: emsg = NULL;
1.201 markus 1447: switch (detect_attack(&state->deattack,
1448: sshbuf_ptr(state->input), padded_len)) {
1449: case DEATTACK_OK:
1450: break;
1.144 djm 1451: case DEATTACK_DETECTED:
1.205 djm 1452: emsg = "crc32 compensation attack detected";
1453: break;
1.144 djm 1454: case DEATTACK_DOS_DETECTED:
1.205 djm 1455: emsg = "deattack denial of service detected";
1456: break;
1.201 markus 1457: default:
1.205 djm 1458: emsg = "deattack error";
1459: break;
1460: }
1461: if (emsg != NULL) {
1462: error("%s", emsg);
1463: if ((r = sshpkt_disconnect(ssh, "%s", emsg)) != 0 ||
1464: (r = ssh_packet_write_wait(ssh)) != 0)
1465: return r;
1466: return SSH_ERR_CONN_CORRUPT;
1.144 djm 1467: }
1468: }
1.62 markus 1469:
1470: /* Decrypt data to incoming_packet. */
1.201 markus 1471: sshbuf_reset(state->incoming_packet);
1472: if ((r = sshbuf_reserve(state->incoming_packet, padded_len, &p)) != 0)
1473: goto out;
1474: if ((r = cipher_crypt(&state->receive_context, 0, p,
1475: sshbuf_ptr(state->input), padded_len, 0, 0)) != 0)
1476: goto out;
1.62 markus 1477:
1.201 markus 1478: if ((r = sshbuf_consume(state->input, padded_len)) != 0)
1479: goto out;
1.1 deraadt 1480:
1481: #ifdef PACKET_DEBUG
1.14 markus 1482: fprintf(stderr, "read_poll plain: ");
1.201 markus 1483: sshbuf_dump(state->incoming_packet, stderr);
1.1 deraadt 1484: #endif
1485:
1.14 markus 1486: /* Compute packet checksum. */
1.201 markus 1487: checksum = ssh_crc32(sshbuf_ptr(state->incoming_packet),
1488: sshbuf_len(state->incoming_packet) - 4);
1.14 markus 1489:
1490: /* Skip padding. */
1.201 markus 1491: if ((r = sshbuf_consume(state->incoming_packet, 8 - len % 8)) != 0)
1492: goto out;
1.14 markus 1493:
1494: /* Test check bytes. */
1.205 djm 1495: if (len != sshbuf_len(state->incoming_packet)) {
1496: error("%s: len %d != sshbuf_len %zd", __func__,
1.201 markus 1497: len, sshbuf_len(state->incoming_packet));
1.205 djm 1498: if ((r = sshpkt_disconnect(ssh, "invalid packet length")) != 0 ||
1499: (r = ssh_packet_write_wait(ssh)) != 0)
1500: return r;
1501: return SSH_ERR_CONN_CORRUPT;
1502: }
1.14 markus 1503:
1.201 markus 1504: cp = sshbuf_ptr(state->incoming_packet) + len - 4;
1505: stored_checksum = PEEK_U32(cp);
1.205 djm 1506: if (checksum != stored_checksum) {
1507: error("Corrupted check bytes on input");
1508: if ((r = sshpkt_disconnect(ssh, "connection corrupted")) != 0 ||
1509: (r = ssh_packet_write_wait(ssh)) != 0)
1510: return r;
1511: return SSH_ERR_CONN_CORRUPT;
1512: }
1.201 markus 1513: if ((r = sshbuf_consume_end(state->incoming_packet, 4)) < 0)
1514: goto out;
1515:
1516: if (state->packet_compression) {
1517: sshbuf_reset(state->compression_buffer);
1518: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1519: state->compression_buffer)) != 0)
1520: goto out;
1521: sshbuf_reset(state->incoming_packet);
1522: if ((r = sshbuf_putb(state->incoming_packet,
1523: state->compression_buffer)) != 0)
1524: goto out;
1525: }
1526: state->p_read.packets++;
1527: state->p_read.bytes += padded_len + 4;
1528: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1529: goto out;
1.205 djm 1530: if (*typep < SSH_MSG_MIN || *typep > SSH_MSG_MAX) {
1531: error("Invalid ssh1 packet type: %d", *typep);
1532: if ((r = sshpkt_disconnect(ssh, "invalid packet type")) != 0 ||
1533: (r = ssh_packet_write_wait(ssh)) != 0)
1534: return r;
1535: return SSH_ERR_PROTOCOL_ERROR;
1536: }
1.201 markus 1537: r = 0;
1538: out:
1539: return r;
1.1 deraadt 1540: }
1.14 markus 1541:
1.201 markus 1542: int
1543: ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1544: {
1.201 markus 1545: struct session_state *state = ssh->state;
1.40 markus 1546: u_int padlen, need;
1.201 markus 1547: u_char *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1548: u_int maclen, aadlen = 0, authlen = 0, block_size;
1549: struct sshenc *enc = NULL;
1550: struct sshmac *mac = NULL;
1551: struct sshcomp *comp = NULL;
1.200 markus 1552: int r;
1.201 markus 1553:
1554: *typep = SSH_MSG_NONE;
1555:
1556: if (state->packet_discard)
1557: return 0;
1558:
1559: if (state->newkeys[MODE_IN] != NULL) {
1560: enc = &state->newkeys[MODE_IN]->enc;
1561: mac = &state->newkeys[MODE_IN]->mac;
1562: comp = &state->newkeys[MODE_IN]->comp;
1.180 markus 1563: /* disable mac for authenticated encryption */
1564: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1565: mac = NULL;
1.25 markus 1566: }
1567: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.88 markus 1568: block_size = enc ? enc->block_size : 8;
1.180 markus 1569: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1570:
1.201 markus 1571: if (aadlen && state->packlen == 0) {
1572: if (cipher_get_length(&state->receive_context,
1573: &state->packlen, state->p_read.seqnr,
1574: sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1575: return 0;
1576: if (state->packlen < 1 + 4 ||
1577: state->packlen > PACKET_MAX_SIZE) {
1.178 markus 1578: #ifdef PACKET_DEBUG
1.201 markus 1579: sshbuf_dump(state->input, stderr);
1.178 markus 1580: #endif
1.201 markus 1581: logit("Bad packet length %u.", state->packlen);
1582: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1583: return r;
1.217 djm 1584: return SSH_ERR_CONN_CORRUPT;
1.178 markus 1585: }
1.201 markus 1586: sshbuf_reset(state->incoming_packet);
1587: } else if (state->packlen == 0) {
1.25 markus 1588: /*
1589: * check if input size is less than the cipher block size,
1590: * decrypt first block and extract length of incoming packet
1591: */
1.201 markus 1592: if (sshbuf_len(state->input) < block_size)
1593: return 0;
1594: sshbuf_reset(state->incoming_packet);
1595: if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1596: &cp)) != 0)
1597: goto out;
1598: if ((r = cipher_crypt(&state->receive_context,
1599: state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1600: block_size, 0, 0)) != 0)
1601: goto out;
1602: state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1603: if (state->packlen < 1 + 4 ||
1604: state->packlen > PACKET_MAX_SIZE) {
1.110 markus 1605: #ifdef PACKET_DEBUG
1.201 markus 1606: fprintf(stderr, "input: \n");
1607: sshbuf_dump(state->input, stderr);
1608: fprintf(stderr, "incoming_packet: \n");
1609: sshbuf_dump(state->incoming_packet, stderr);
1.110 markus 1610: #endif
1.201 markus 1611: logit("Bad packet length %u.", state->packlen);
1612: return ssh_packet_start_discard(ssh, enc, mac,
1613: state->packlen, PACKET_MAX_SIZE);
1.25 markus 1614: }
1.201 markus 1615: if ((r = sshbuf_consume(state->input, block_size)) != 0)
1616: goto out;
1.25 markus 1617: }
1.201 markus 1618: DBG(debug("input: packet len %u", state->packlen+4));
1619:
1.178 markus 1620: if (aadlen) {
1621: /* only the payload is encrypted */
1.201 markus 1622: need = state->packlen;
1.178 markus 1623: } else {
1624: /*
1625: * the payload size and the payload are encrypted, but we
1626: * have a partial packet of block_size bytes
1627: */
1.201 markus 1628: need = 4 + state->packlen - block_size;
1.178 markus 1629: }
1.180 markus 1630: DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1631: " aadlen %d", block_size, need, maclen, authlen, aadlen));
1.158 markus 1632: if (need % block_size != 0) {
1633: logit("padding error: need %d block %d mod %d",
1.25 markus 1634: need, block_size, need % block_size);
1.201 markus 1635: return ssh_packet_start_discard(ssh, enc, mac,
1636: state->packlen, PACKET_MAX_SIZE - block_size);
1.158 markus 1637: }
1.25 markus 1638: /*
1639: * check if the entire packet has been received and
1.178 markus 1640: * decrypt into incoming_packet:
1641: * 'aadlen' bytes are unencrypted, but authenticated.
1.180 markus 1642: * 'need' bytes are encrypted, followed by either
1643: * 'authlen' bytes of authentication tag or
1.178 markus 1644: * 'maclen' bytes of message authentication code.
1.25 markus 1645: */
1.201 markus 1646: if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1647: return 0;
1.25 markus 1648: #ifdef PACKET_DEBUG
1649: fprintf(stderr, "read_poll enc/full: ");
1.201 markus 1650: sshbuf_dump(state->input, stderr);
1.25 markus 1651: #endif
1.178 markus 1652: /* EtM: compute mac over encrypted input */
1.201 markus 1653: if (mac && mac->enabled && mac->etm) {
1654: if ((r = mac_compute(mac, state->p_read.seqnr,
1655: sshbuf_ptr(state->input), aadlen + need,
1.200 markus 1656: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1657: goto out;
1658: }
1659: if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1660: &cp)) != 0)
1661: goto out;
1662: if ((r = cipher_crypt(&state->receive_context, state->p_read.seqnr, cp,
1663: sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1664: goto out;
1665: if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1666: goto out;
1.25 markus 1667: /*
1668: * compute MAC over seqnr and packet,
1669: * increment sequence number for incoming packet
1670: */
1.29 markus 1671: if (mac && mac->enabled) {
1.178 markus 1672: if (!mac->etm)
1.201 markus 1673: if ((r = mac_compute(mac, state->p_read.seqnr,
1674: sshbuf_ptr(state->incoming_packet),
1675: sshbuf_len(state->incoming_packet),
1.200 markus 1676: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1677: goto out;
1678: if (timingsafe_bcmp(macbuf, sshbuf_ptr(state->input),
1.161 andreas 1679: mac->mac_len) != 0) {
1.159 markus 1680: logit("Corrupted MAC on input.");
1681: if (need > PACKET_MAX_SIZE)
1.201 markus 1682: return SSH_ERR_INTERNAL_ERROR;
1683: return ssh_packet_start_discard(ssh, enc, mac,
1684: state->packlen, PACKET_MAX_SIZE - need);
1685: }
1686:
1687: DBG(debug("MAC #%d ok", state->p_read.seqnr));
1688: if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1689: goto out;
1.25 markus 1690: }
1.77 djm 1691: if (seqnr_p != NULL)
1.201 markus 1692: *seqnr_p = state->p_read.seqnr;
1693: if (++state->p_read.seqnr == 0)
1.106 itojun 1694: logit("incoming seqnr wraps around");
1.201 markus 1695: if (++state->p_read.packets == 0)
1696: if (!(ssh->compat & SSH_BUG_NOREKEY))
1697: return SSH_ERR_NEED_REKEY;
1698: state->p_read.blocks += (state->packlen + 4) / block_size;
1699: state->p_read.bytes += state->packlen + 4;
1.25 markus 1700:
1701: /* get padlen */
1.201 markus 1702: padlen = sshbuf_ptr(state->incoming_packet)[4];
1.25 markus 1703: DBG(debug("input: padlen %d", padlen));
1.205 djm 1704: if (padlen < 4) {
1705: if ((r = sshpkt_disconnect(ssh,
1706: "Corrupted padlen %d on input.", padlen)) != 0 ||
1707: (r = ssh_packet_write_wait(ssh)) != 0)
1708: return r;
1709: return SSH_ERR_CONN_CORRUPT;
1710: }
1.25 markus 1711:
1712: /* skip packet size + padlen, discard padding */
1.201 markus 1713: if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1714: ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1715: goto out;
1.25 markus 1716:
1.201 markus 1717: DBG(debug("input: len before de-compress %zd",
1718: sshbuf_len(state->incoming_packet)));
1.25 markus 1719: if (comp && comp->enabled) {
1.201 markus 1720: sshbuf_reset(state->compression_buffer);
1721: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1722: state->compression_buffer)) != 0)
1723: goto out;
1724: sshbuf_reset(state->incoming_packet);
1725: if ((r = sshbuf_putb(state->incoming_packet,
1726: state->compression_buffer)) != 0)
1727: goto out;
1728: DBG(debug("input: len after de-compress %zd",
1729: sshbuf_len(state->incoming_packet)));
1.25 markus 1730: }
1731: /*
1732: * get packet type, implies consume.
1733: * return length of payload (without type field)
1734: */
1.201 markus 1735: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1736: goto out;
1.205 djm 1737: if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1738: if ((r = sshpkt_disconnect(ssh,
1739: "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1740: (r = ssh_packet_write_wait(ssh)) != 0)
1741: return r;
1742: return SSH_ERR_PROTOCOL_ERROR;
1743: }
1.201 markus 1744: if (*typep == SSH2_MSG_NEWKEYS)
1745: r = ssh_set_newkeys(ssh, MODE_IN);
1746: else if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1747: r = ssh_packet_enable_delayed_compress(ssh);
1748: else
1749: r = 0;
1.25 markus 1750: #ifdef PACKET_DEBUG
1.201 markus 1751: fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1752: sshbuf_dump(state->incoming_packet, stderr);
1.25 markus 1753: #endif
1.62 markus 1754: /* reset for next packet */
1.201 markus 1755: state->packlen = 0;
1756: out:
1757: return r;
1.25 markus 1758: }
1759:
1760: int
1.201 markus 1761: ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1762: {
1.201 markus 1763: struct session_state *state = ssh->state;
1.96 deraadt 1764: u_int reason, seqnr;
1.201 markus 1765: int r;
1766: u_char *msg;
1.62 markus 1767:
1.25 markus 1768: for (;;) {
1.201 markus 1769: msg = NULL;
1.62 markus 1770: if (compat20) {
1.201 markus 1771: r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1772: if (r != 0)
1773: return r;
1774: if (*typep) {
1775: state->keep_alive_timeouts = 0;
1776: DBG(debug("received packet type %d", *typep));
1.153 djm 1777: }
1.201 markus 1778: switch (*typep) {
1.150 dtucker 1779: case SSH2_MSG_IGNORE:
1.151 dtucker 1780: debug3("Received SSH2_MSG_IGNORE");
1.150 dtucker 1781: break;
1.25 markus 1782: case SSH2_MSG_DEBUG:
1.201 markus 1783: if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1784: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1785: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1.219 mmcc 1786: free(msg);
1.201 markus 1787: return r;
1788: }
1.25 markus 1789: debug("Remote: %.900s", msg);
1.186 djm 1790: free(msg);
1.25 markus 1791: break;
1792: case SSH2_MSG_DISCONNECT:
1.201 markus 1793: if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1794: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1795: return r;
1.182 djm 1796: /* Ignore normal client exit notifications */
1.201 markus 1797: do_log2(ssh->state->server_side &&
1.182 djm 1798: reason == SSH2_DISCONNECT_BY_APPLICATION ?
1799: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1.220 djm 1800: "Received disconnect from %s port %d:"
1801: "%u: %.400s", ssh_remote_ipaddr(ssh),
1802: ssh_remote_port(ssh), reason, msg);
1.186 djm 1803: free(msg);
1.201 markus 1804: return SSH_ERR_DISCONNECTED;
1.84 markus 1805: case SSH2_MSG_UNIMPLEMENTED:
1.201 markus 1806: if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1807: return r;
1.96 deraadt 1808: debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1809: seqnr);
1.150 dtucker 1810: break;
1.25 markus 1811: default:
1.201 markus 1812: return 0;
1.48 stevesk 1813: }
1.25 markus 1814: } else {
1.201 markus 1815: r = ssh_packet_read_poll1(ssh, typep);
1816: switch (*typep) {
1.188 djm 1817: case SSH_MSG_NONE:
1818: return SSH_MSG_NONE;
1.25 markus 1819: case SSH_MSG_IGNORE:
1820: break;
1821: case SSH_MSG_DEBUG:
1.201 markus 1822: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1823: return r;
1.25 markus 1824: debug("Remote: %.900s", msg);
1.186 djm 1825: free(msg);
1.25 markus 1826: break;
1827: case SSH_MSG_DISCONNECT:
1.201 markus 1828: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1829: return r;
1.220 djm 1830: error("Received disconnect from %s port %d: "
1831: "%.400s", ssh_remote_ipaddr(ssh),
1832: ssh_remote_port(ssh), msg);
1.201 markus 1833: free(msg);
1834: return SSH_ERR_DISCONNECTED;
1.25 markus 1835: default:
1.201 markus 1836: DBG(debug("received packet type %d", *typep));
1837: return 0;
1.48 stevesk 1838: }
1.25 markus 1839: }
1840: }
1841: }
1842:
1.16 markus 1843: /*
1844: * Buffers the given amount of input characters. This is intended to be used
1845: * together with packet_read_poll.
1846: */
1.1 deraadt 1847:
1.204 djm 1848: int
1.201 markus 1849: ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1.1 deraadt 1850: {
1.201 markus 1851: struct session_state *state = ssh->state;
1852: int r;
1853:
1854: if (state->packet_discard) {
1855: state->keep_alive_timeouts = 0; /* ?? */
1856: if (len >= state->packet_discard) {
1857: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1.204 djm 1858: return r;
1.201 markus 1859: }
1860: state->packet_discard -= len;
1.204 djm 1861: return 0;
1.159 markus 1862: }
1.201 markus 1863: if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1.204 djm 1864: return r;
1865:
1866: return 0;
1.28 markus 1867: }
1868:
1869: int
1.201 markus 1870: ssh_packet_remaining(struct ssh *ssh)
1.28 markus 1871: {
1.201 markus 1872: return sshbuf_len(ssh->state->incoming_packet);
1.1 deraadt 1873: }
1874:
1.16 markus 1875: /*
1876: * Sends a diagnostic message from the server to the client. This message
1877: * can be sent at any time (but not while constructing another message). The
1878: * message is printed immediately, but only if the client is being executed
1879: * in verbose mode. These messages are primarily intended to ease debugging
1880: * authentication problems. The length of the formatted message must not
1.205 djm 1881: * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1.16 markus 1882: */
1.2 provos 1883: void
1.201 markus 1884: ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1885: {
1.14 markus 1886: char buf[1024];
1887: va_list args;
1.201 markus 1888: int r;
1.39 markus 1889:
1.201 markus 1890: if (compat20 && (ssh->compat & SSH_BUG_DEBUG))
1.39 markus 1891: return;
1.14 markus 1892:
1893: va_start(args, fmt);
1894: vsnprintf(buf, sizeof(buf), fmt, args);
1895: va_end(args);
1896:
1.30 markus 1897: if (compat20) {
1.201 markus 1898: if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1899: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1900: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1901: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1902: (r = sshpkt_send(ssh)) != 0)
1903: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1904: } else {
1.201 markus 1905: if ((r = sshpkt_start(ssh, SSH_MSG_DEBUG)) != 0 ||
1906: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1907: (r = sshpkt_send(ssh)) != 0)
1908: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1909: }
1.205 djm 1910: if ((r = ssh_packet_write_wait(ssh)) != 0)
1911: fatal("%s: %s", __func__, ssh_err(r));
1912: }
1913:
1914: /*
1915: * Pretty-print connection-terminating errors and exit.
1916: */
1917: void
1918: sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1919: {
1920: switch (r) {
1921: case SSH_ERR_CONN_CLOSED:
1.220 djm 1922: logit("Connection closed by %.200s port %d",
1923: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.205 djm 1924: cleanup_exit(255);
1925: case SSH_ERR_CONN_TIMEOUT:
1.220 djm 1926: logit("Connection %s %.200s port %d timed out",
1927: ssh->state->server_side ? "from" : "to",
1928: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.205 djm 1929: cleanup_exit(255);
1.212 djm 1930: case SSH_ERR_DISCONNECTED:
1.220 djm 1931: logit("Disconnected from %.200s port %d",
1932: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 1933: cleanup_exit(255);
1934: case SSH_ERR_SYSTEM_ERROR:
1935: if (errno == ECONNRESET) {
1.220 djm 1936: logit("Connection reset by %.200s port %d",
1937: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 1938: cleanup_exit(255);
1.213 djm 1939: }
1940: /* FALLTHROUGH */
1941: case SSH_ERR_NO_CIPHER_ALG_MATCH:
1942: case SSH_ERR_NO_MAC_ALG_MATCH:
1943: case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1944: case SSH_ERR_NO_KEX_ALG_MATCH:
1945: case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1946: if (ssh && ssh->kex && ssh->kex->failed_choice) {
1.220 djm 1947: fatal("Unable to negotiate with %.200s port %d: %s. "
1.213 djm 1948: "Their offer: %s", ssh_remote_ipaddr(ssh),
1.220 djm 1949: ssh_remote_port(ssh), ssh_err(r),
1950: ssh->kex->failed_choice);
1.212 djm 1951: }
1952: /* FALLTHROUGH */
1.205 djm 1953: default:
1.220 djm 1954: fatal("%s%sConnection %s %.200s port %d: %s",
1.205 djm 1955: tag != NULL ? tag : "", tag != NULL ? ": " : "",
1.220 djm 1956: ssh->state->server_side ? "from" : "to",
1957: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), ssh_err(r));
1.205 djm 1958: }
1.1 deraadt 1959: }
1960:
1.16 markus 1961: /*
1962: * Logs the error plus constructs and sends a disconnect packet, closes the
1963: * connection, and exits. This function never returns. The error message
1964: * should not contain a newline. The length of the formatted message must
1965: * not exceed 1024 bytes.
1966: */
1.2 provos 1967: void
1.201 markus 1968: ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1969: {
1.14 markus 1970: char buf[1024];
1971: va_list args;
1972: static int disconnecting = 0;
1.201 markus 1973: int r;
1.97 deraadt 1974:
1.14 markus 1975: if (disconnecting) /* Guard against recursive invocations. */
1976: fatal("packet_disconnect called recursively.");
1977: disconnecting = 1;
1978:
1.16 markus 1979: /*
1980: * Format the message. Note that the caller must make sure the
1981: * message is of limited size.
1982: */
1.14 markus 1983: va_start(args, fmt);
1984: vsnprintf(buf, sizeof(buf), fmt, args);
1985: va_end(args);
1986:
1.99 markus 1987: /* Display the error locally */
1.106 itojun 1988: logit("Disconnecting: %.100s", buf);
1.99 markus 1989:
1.205 djm 1990: /*
1991: * Send the disconnect message to the other side, and wait
1992: * for it to get sent.
1993: */
1994: if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1995: sshpkt_fatal(ssh, __func__, r);
1996:
1997: if ((r = ssh_packet_write_wait(ssh)) != 0)
1998: sshpkt_fatal(ssh, __func__, r);
1.14 markus 1999:
2000: /* Close the connection. */
1.201 markus 2001: ssh_packet_close(ssh);
1.112 markus 2002: cleanup_exit(255);
1.1 deraadt 2003: }
2004:
1.205 djm 2005: /*
2006: * Checks if there is any buffered output, and tries to write some of
2007: * the output.
2008: */
2009: int
1.201 markus 2010: ssh_packet_write_poll(struct ssh *ssh)
1.1 deraadt 2011: {
1.201 markus 2012: struct session_state *state = ssh->state;
2013: int len = sshbuf_len(state->output);
1.222 markus 2014: int r;
1.97 deraadt 2015:
1.14 markus 2016: if (len > 0) {
1.222 markus 2017: len = write(state->connection_out,
2018: sshbuf_ptr(state->output), len);
1.156 djm 2019: if (len == -1) {
2020: if (errno == EINTR || errno == EAGAIN)
1.205 djm 2021: return 0;
2022: return SSH_ERR_SYSTEM_ERROR;
1.14 markus 2023: }
1.222 markus 2024: if (len == 0)
1.205 djm 2025: return SSH_ERR_CONN_CLOSED;
1.201 markus 2026: if ((r = sshbuf_consume(state->output, len)) != 0)
1.205 djm 2027: return r;
1.14 markus 2028: }
1.205 djm 2029: return 0;
1.1 deraadt 2030: }
2031:
1.16 markus 2032: /*
2033: * Calls packet_write_poll repeatedly until all pending output data has been
2034: * written.
2035: */
1.205 djm 2036: int
1.201 markus 2037: ssh_packet_write_wait(struct ssh *ssh)
1.1 deraadt 2038: {
1.56 millert 2039: fd_set *setp;
1.205 djm 2040: int ret, r, ms_remain = 0;
1.154 dtucker 2041: struct timeval start, timeout, *timeoutp = NULL;
1.201 markus 2042: struct session_state *state = ssh->state;
1.56 millert 2043:
1.214 deraadt 2044: setp = calloc(howmany(state->connection_out + 1,
1.161 andreas 2045: NFDBITS), sizeof(fd_mask));
1.201 markus 2046: if (setp == NULL)
1.205 djm 2047: return SSH_ERR_ALLOC_FAIL;
1.216 gsoares 2048: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2049: free(setp);
1.215 djm 2050: return r;
1.216 gsoares 2051: }
1.201 markus 2052: while (ssh_packet_have_data_to_write(ssh)) {
2053: memset(setp, 0, howmany(state->connection_out + 1,
1.161 andreas 2054: NFDBITS) * sizeof(fd_mask));
1.201 markus 2055: FD_SET(state->connection_out, setp);
1.154 dtucker 2056:
1.201 markus 2057: if (state->packet_timeout_ms > 0) {
2058: ms_remain = state->packet_timeout_ms;
1.154 dtucker 2059: timeoutp = &timeout;
2060: }
2061: for (;;) {
1.201 markus 2062: if (state->packet_timeout_ms != -1) {
1.154 dtucker 2063: ms_to_timeval(&timeout, ms_remain);
2064: gettimeofday(&start, NULL);
2065: }
1.201 markus 2066: if ((ret = select(state->connection_out + 1,
1.161 andreas 2067: NULL, setp, NULL, timeoutp)) >= 0)
1.154 dtucker 2068: break;
1.161 andreas 2069: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 2070: break;
1.201 markus 2071: if (state->packet_timeout_ms == -1)
1.154 dtucker 2072: continue;
2073: ms_subtract_diff(&start, &ms_remain);
2074: if (ms_remain <= 0) {
2075: ret = 0;
2076: break;
2077: }
2078: }
2079: if (ret == 0) {
1.205 djm 2080: free(setp);
2081: return SSH_ERR_CONN_TIMEOUT;
2082: }
2083: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2084: free(setp);
2085: return r;
1.154 dtucker 2086: }
1.14 markus 2087: }
1.186 djm 2088: free(setp);
1.205 djm 2089: return 0;
1.1 deraadt 2090: }
2091:
2092: /* Returns true if there is buffered data to write to the connection. */
2093:
1.2 provos 2094: int
1.201 markus 2095: ssh_packet_have_data_to_write(struct ssh *ssh)
1.1 deraadt 2096: {
1.201 markus 2097: return sshbuf_len(ssh->state->output) != 0;
1.1 deraadt 2098: }
2099:
2100: /* Returns true if there is not too much data to write to the connection. */
2101:
1.2 provos 2102: int
1.201 markus 2103: ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1.1 deraadt 2104: {
1.201 markus 2105: if (ssh->state->interactive_mode)
2106: return sshbuf_len(ssh->state->output) < 16384;
1.14 markus 2107: else
1.201 markus 2108: return sshbuf_len(ssh->state->output) < 128 * 1024;
1.1 deraadt 2109: }
2110:
1.201 markus 2111: void
2112: ssh_packet_set_tos(struct ssh *ssh, int tos)
1.101 markus 2113: {
1.201 markus 2114: if (!ssh_packet_connection_is_on_socket(ssh))
1.101 markus 2115: return;
1.201 markus 2116: switch (ssh_packet_connection_af(ssh)) {
1.173 djm 2117: case AF_INET:
2118: debug3("%s: set IP_TOS 0x%02x", __func__, tos);
1.201 markus 2119: if (setsockopt(ssh->state->connection_in,
1.173 djm 2120: IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2121: error("setsockopt IP_TOS %d: %.100s:",
2122: tos, strerror(errno));
2123: break;
2124: case AF_INET6:
2125: debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
1.201 markus 2126: if (setsockopt(ssh->state->connection_in,
1.173 djm 2127: IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2128: error("setsockopt IPV6_TCLASS %d: %.100s:",
2129: tos, strerror(errno));
2130: break;
2131: }
1.101 markus 2132: }
2133:
1.1 deraadt 2134: /* Informs that the current session is interactive. Sets IP flags for that. */
2135:
1.2 provos 2136: void
1.201 markus 2137: ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
1.1 deraadt 2138: {
1.201 markus 2139: struct session_state *state = ssh->state;
2140:
2141: if (state->set_interactive_called)
1.43 markus 2142: return;
1.201 markus 2143: state->set_interactive_called = 1;
1.1 deraadt 2144:
1.14 markus 2145: /* Record that we are in interactive mode. */
1.201 markus 2146: state->interactive_mode = interactive;
1.1 deraadt 2147:
1.19 markus 2148: /* Only set socket options if using a socket. */
1.201 markus 2149: if (!ssh_packet_connection_is_on_socket(ssh))
1.14 markus 2150: return;
1.201 markus 2151: set_nodelay(state->connection_in);
2152: ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2153: qos_bulk);
1.1 deraadt 2154: }
2155:
2156: /* Returns true if the current connection is interactive. */
2157:
1.2 provos 2158: int
1.201 markus 2159: ssh_packet_is_interactive(struct ssh *ssh)
1.1 deraadt 2160: {
1.201 markus 2161: return ssh->state->interactive_mode;
1.12 markus 2162: }
2163:
1.113 deraadt 2164: int
1.201 markus 2165: ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
1.12 markus 2166: {
1.201 markus 2167: struct session_state *state = ssh->state;
2168:
2169: if (state->set_maxsize_called) {
1.106 itojun 2170: logit("packet_set_maxsize: called twice: old %d new %d",
1.201 markus 2171: state->max_packet_size, s);
1.14 markus 2172: return -1;
2173: }
2174: if (s < 4 * 1024 || s > 1024 * 1024) {
1.106 itojun 2175: logit("packet_set_maxsize: bad size %d", s);
1.14 markus 2176: return -1;
2177: }
1.201 markus 2178: state->set_maxsize_called = 1;
1.66 markus 2179: debug("packet_set_maxsize: setting to %d", s);
1.201 markus 2180: state->max_packet_size = s;
1.14 markus 2181: return s;
1.53 markus 2182: }
2183:
1.161 andreas 2184: int
1.201 markus 2185: ssh_packet_inc_alive_timeouts(struct ssh *ssh)
1.161 andreas 2186: {
1.201 markus 2187: return ++ssh->state->keep_alive_timeouts;
1.161 andreas 2188: }
2189:
2190: void
1.201 markus 2191: ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
1.161 andreas 2192: {
1.201 markus 2193: ssh->state->keep_alive_timeouts = ka;
1.161 andreas 2194: }
2195:
2196: u_int
1.201 markus 2197: ssh_packet_get_maxsize(struct ssh *ssh)
1.71 markus 2198: {
1.201 markus 2199: return ssh->state->max_packet_size;
1.71 markus 2200: }
2201:
1.53 markus 2202: /*
2203: * 9.2. Ignored Data Message
1.61 markus 2204: *
1.53 markus 2205: * byte SSH_MSG_IGNORE
2206: * string data
1.61 markus 2207: *
1.53 markus 2208: * All implementations MUST understand (and ignore) this message at any
2209: * time (after receiving the protocol version). No implementation is
2210: * required to send them. This message can be used as an additional
2211: * protection measure against advanced traffic analysis techniques.
2212: */
1.54 markus 2213: void
1.201 markus 2214: ssh_packet_send_ignore(struct ssh *ssh, int nbytes)
1.54 markus 2215: {
1.115 avsm 2216: u_int32_t rnd = 0;
1.201 markus 2217: int r, i;
1.54 markus 2218:
1.201 markus 2219: if ((r = sshpkt_start(ssh, compat20 ?
2220: SSH2_MSG_IGNORE : SSH_MSG_IGNORE)) != 0 ||
2221: (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2222: fatal("%s: %s", __func__, ssh_err(r));
1.75 deraadt 2223: for (i = 0; i < nbytes; i++) {
1.53 markus 2224: if (i % 4 == 0)
1.115 avsm 2225: rnd = arc4random();
1.201 markus 2226: if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2227: fatal("%s: %s", __func__, ssh_err(r));
1.115 avsm 2228: rnd >>= 8;
1.53 markus 2229: }
1.105 markus 2230: }
2231:
1.113 deraadt 2232: #define MAX_PACKETS (1U<<31)
1.105 markus 2233: int
1.201 markus 2234: ssh_packet_need_rekeying(struct ssh *ssh)
1.105 markus 2235: {
1.201 markus 2236: struct session_state *state = ssh->state;
2237:
2238: if (ssh->compat & SSH_BUG_NOREKEY)
1.105 markus 2239: return 0;
2240: return
1.201 markus 2241: (state->p_send.packets > MAX_PACKETS) ||
2242: (state->p_read.packets > MAX_PACKETS) ||
2243: (state->max_blocks_out &&
1.225 ! dtucker 2244: (state->p_send.blocks > state->max_blocks_out)) ||
1.201 markus 2245: (state->max_blocks_in &&
1.225 ! dtucker 2246: (state->p_read.blocks > state->max_blocks_in)) ||
1.201 markus 2247: (state->rekey_interval != 0 && state->rekey_time +
2248: state->rekey_interval <= monotime());
1.105 markus 2249: }
2250:
2251: void
1.224 dtucker 2252: ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, time_t seconds)
1.105 markus 2253: {
1.224 dtucker 2254: debug3("rekey after %llu bytes, %d seconds", (unsigned long long)bytes,
1.184 dtucker 2255: (int)seconds);
1.201 markus 2256: ssh->state->rekey_limit = bytes;
2257: ssh->state->rekey_interval = seconds;
1.184 dtucker 2258: }
2259:
2260: time_t
1.201 markus 2261: ssh_packet_get_rekey_timeout(struct ssh *ssh)
1.184 dtucker 2262: {
2263: time_t seconds;
2264:
1.201 markus 2265: seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
1.187 dtucker 2266: monotime();
1.185 dtucker 2267: return (seconds <= 0 ? 1 : seconds);
1.118 markus 2268: }
2269:
2270: void
1.201 markus 2271: ssh_packet_set_server(struct ssh *ssh)
1.118 markus 2272: {
1.201 markus 2273: ssh->state->server_side = 1;
1.118 markus 2274: }
2275:
2276: void
1.201 markus 2277: ssh_packet_set_authenticated(struct ssh *ssh)
1.118 markus 2278: {
1.201 markus 2279: ssh->state->after_authentication = 1;
1.161 andreas 2280: }
2281:
2282: void *
1.201 markus 2283: ssh_packet_get_input(struct ssh *ssh)
1.161 andreas 2284: {
1.201 markus 2285: return (void *)ssh->state->input;
1.161 andreas 2286: }
2287:
2288: void *
1.201 markus 2289: ssh_packet_get_output(struct ssh *ssh)
1.161 andreas 2290: {
1.201 markus 2291: return (void *)ssh->state->output;
1.166 andreas 2292: }
2293:
1.196 markus 2294: /* Reset after_authentication and reset compression in post-auth privsep */
1.201 markus 2295: static int
2296: ssh_packet_set_postauth(struct ssh *ssh)
1.196 markus 2297: {
1.201 markus 2298: struct sshcomp *comp;
2299: int r, mode;
1.196 markus 2300:
2301: debug("%s: called", __func__);
2302: /* This was set in net child, but is not visible in user child */
1.201 markus 2303: ssh->state->after_authentication = 1;
2304: ssh->state->rekeying = 0;
1.196 markus 2305: for (mode = 0; mode < MODE_MAX; mode++) {
1.201 markus 2306: if (ssh->state->newkeys[mode] == NULL)
1.196 markus 2307: continue;
1.201 markus 2308: comp = &ssh->state->newkeys[mode]->comp;
2309: if (comp && comp->enabled &&
2310: (r = ssh_packet_init_compression(ssh)) != 0)
2311: return r;
2312: }
2313: return 0;
2314: }
2315:
2316: /* Packet state (de-)serialization for privsep */
2317:
2318: /* turn kex into a blob for packet state serialization */
2319: static int
2320: kex_to_blob(struct sshbuf *m, struct kex *kex)
2321: {
2322: int r;
2323:
2324: if ((r = sshbuf_put_string(m, kex->session_id,
2325: kex->session_id_len)) != 0 ||
2326: (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2327: (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2328: (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2329: (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2330: (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2331: (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2332: (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2333: (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2334: return r;
2335: return 0;
2336: }
2337:
2338: /* turn key exchange results into a blob for packet state serialization */
2339: static int
2340: newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2341: {
2342: struct sshbuf *b;
2343: struct sshcipher_ctx *cc;
2344: struct sshcomp *comp;
2345: struct sshenc *enc;
2346: struct sshmac *mac;
2347: struct newkeys *newkey;
2348: int r;
2349:
2350: if ((newkey = ssh->state->newkeys[mode]) == NULL)
2351: return SSH_ERR_INTERNAL_ERROR;
2352: enc = &newkey->enc;
2353: mac = &newkey->mac;
2354: comp = &newkey->comp;
2355: cc = (mode == MODE_OUT) ? &ssh->state->send_context :
2356: &ssh->state->receive_context;
2357: if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2358: return r;
2359: if ((b = sshbuf_new()) == NULL)
2360: return SSH_ERR_ALLOC_FAIL;
2361: /* The cipher struct is constant and shared, you export pointer */
2362: if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2363: (r = sshbuf_put(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2364: (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2365: (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2366: (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2367: (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2368: goto out;
2369: if (cipher_authlen(enc->cipher) == 0) {
2370: if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2371: (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2372: (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2373: goto out;
2374: }
2375: if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2376: (r = sshbuf_put_u32(b, comp->enabled)) != 0 ||
2377: (r = sshbuf_put_cstring(b, comp->name)) != 0)
2378: goto out;
2379: r = sshbuf_put_stringb(m, b);
2380: out:
1.221 mmcc 2381: sshbuf_free(b);
1.201 markus 2382: return r;
2383: }
2384:
2385: /* serialize packet state into a blob */
2386: int
2387: ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2388: {
2389: struct session_state *state = ssh->state;
2390: u_char *p;
2391: size_t slen, rlen;
2392: int r, ssh1cipher;
2393:
2394: if (!compat20) {
2395: ssh1cipher = cipher_get_number(state->receive_context.cipher);
2396: slen = cipher_get_keyiv_len(&state->send_context);
2397: rlen = cipher_get_keyiv_len(&state->receive_context);
2398: if ((r = sshbuf_put_u32(m, state->remote_protocol_flags)) != 0 ||
2399: (r = sshbuf_put_u32(m, ssh1cipher)) != 0 ||
2400: (r = sshbuf_put_string(m, state->ssh1_key, state->ssh1_keylen)) != 0 ||
2401: (r = sshbuf_put_u32(m, slen)) != 0 ||
2402: (r = sshbuf_reserve(m, slen, &p)) != 0 ||
2403: (r = cipher_get_keyiv(&state->send_context, p, slen)) != 0 ||
2404: (r = sshbuf_put_u32(m, rlen)) != 0 ||
2405: (r = sshbuf_reserve(m, rlen, &p)) != 0 ||
2406: (r = cipher_get_keyiv(&state->receive_context, p, rlen)) != 0)
2407: return r;
2408: } else {
2409: if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2410: (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2411: (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
1.224 dtucker 2412: (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
1.208 markus 2413: (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
1.201 markus 2414: (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2415: (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2416: (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2417: (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2418: (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2419: (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2420: (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2421: (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0)
2422: return r;
2423: }
2424:
2425: slen = cipher_get_keycontext(&state->send_context, NULL);
2426: rlen = cipher_get_keycontext(&state->receive_context, NULL);
2427: if ((r = sshbuf_put_u32(m, slen)) != 0 ||
2428: (r = sshbuf_reserve(m, slen, &p)) != 0)
2429: return r;
2430: if (cipher_get_keycontext(&state->send_context, p) != (int)slen)
2431: return SSH_ERR_INTERNAL_ERROR;
2432: if ((r = sshbuf_put_u32(m, rlen)) != 0 ||
2433: (r = sshbuf_reserve(m, rlen, &p)) != 0)
2434: return r;
2435: if (cipher_get_keycontext(&state->receive_context, p) != (int)rlen)
2436: return SSH_ERR_INTERNAL_ERROR;
2437:
2438: if ((r = ssh_packet_get_compress_state(m, ssh)) != 0 ||
2439: (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2440: (r = sshbuf_put_stringb(m, state->output)) != 0)
2441: return r;
2442:
2443: return 0;
2444: }
2445:
2446: /* restore key exchange results from blob for packet state de-serialization */
2447: static int
2448: newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2449: {
2450: struct sshbuf *b = NULL;
2451: struct sshcomp *comp;
2452: struct sshenc *enc;
2453: struct sshmac *mac;
2454: struct newkeys *newkey = NULL;
2455: size_t keylen, ivlen, maclen;
2456: int r;
2457:
2458: if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2459: r = SSH_ERR_ALLOC_FAIL;
2460: goto out;
2461: }
2462: if ((r = sshbuf_froms(m, &b)) != 0)
2463: goto out;
2464: #ifdef DEBUG_PK
2465: sshbuf_dump(b, stderr);
2466: #endif
2467: enc = &newkey->enc;
2468: mac = &newkey->mac;
2469: comp = &newkey->comp;
2470:
2471: if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2472: (r = sshbuf_get(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2473: (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2474: (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2475: (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2476: (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2477: goto out;
2478: if (cipher_authlen(enc->cipher) == 0) {
2479: if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2480: goto out;
2481: if ((r = mac_setup(mac, mac->name)) != 0)
2482: goto out;
2483: if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2484: (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2485: goto out;
2486: if (maclen > mac->key_len) {
2487: r = SSH_ERR_INVALID_FORMAT;
2488: goto out;
2489: }
2490: mac->key_len = maclen;
2491: }
2492: if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2493: (r = sshbuf_get_u32(b, (u_int *)&comp->enabled)) != 0 ||
2494: (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2495: goto out;
2496: if (enc->name == NULL ||
2497: cipher_by_name(enc->name) != enc->cipher) {
2498: r = SSH_ERR_INVALID_FORMAT;
2499: goto out;
2500: }
2501: if (sshbuf_len(b) != 0) {
2502: r = SSH_ERR_INVALID_FORMAT;
2503: goto out;
2504: }
2505: enc->key_len = keylen;
2506: enc->iv_len = ivlen;
2507: ssh->kex->newkeys[mode] = newkey;
2508: newkey = NULL;
2509: r = 0;
2510: out:
1.219 mmcc 2511: free(newkey);
1.221 mmcc 2512: sshbuf_free(b);
1.201 markus 2513: return r;
2514: }
2515:
2516: /* restore kex from blob for packet state de-serialization */
2517: static int
2518: kex_from_blob(struct sshbuf *m, struct kex **kexp)
2519: {
2520: struct kex *kex;
2521: int r;
2522:
2523: if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2524: (kex->my = sshbuf_new()) == NULL ||
2525: (kex->peer = sshbuf_new()) == NULL) {
2526: r = SSH_ERR_ALLOC_FAIL;
2527: goto out;
2528: }
2529: if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2530: (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2531: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2532: (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2533: (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2534: (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2535: (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2536: (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2537: (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2538: goto out;
2539: kex->server = 1;
2540: kex->done = 1;
2541: r = 0;
2542: out:
2543: if (r != 0 || kexp == NULL) {
2544: if (kex != NULL) {
1.221 mmcc 2545: sshbuf_free(kex->my);
2546: sshbuf_free(kex->peer);
1.201 markus 2547: free(kex);
2548: }
2549: if (kexp != NULL)
2550: *kexp = NULL;
2551: } else {
2552: *kexp = kex;
2553: }
2554: return r;
2555: }
2556:
2557: /*
2558: * Restore packet state from content of blob 'm' (de-serialization).
2559: * Note that 'm' will be partially consumed on parsing or any other errors.
2560: */
2561: int
2562: ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2563: {
2564: struct session_state *state = ssh->state;
2565: const u_char *ssh1key, *ivin, *ivout, *keyin, *keyout, *input, *output;
2566: size_t ssh1keylen, rlen, slen, ilen, olen;
2567: int r;
2568: u_int ssh1cipher = 0;
2569:
2570: if (!compat20) {
2571: if ((r = sshbuf_get_u32(m, &state->remote_protocol_flags)) != 0 ||
2572: (r = sshbuf_get_u32(m, &ssh1cipher)) != 0 ||
2573: (r = sshbuf_get_string_direct(m, &ssh1key, &ssh1keylen)) != 0 ||
2574: (r = sshbuf_get_string_direct(m, &ivout, &slen)) != 0 ||
2575: (r = sshbuf_get_string_direct(m, &ivin, &rlen)) != 0)
2576: return r;
2577: if (ssh1cipher > INT_MAX)
2578: return SSH_ERR_KEY_UNKNOWN_CIPHER;
2579: ssh_packet_set_encryption_key(ssh, ssh1key, ssh1keylen,
2580: (int)ssh1cipher);
2581: if (cipher_get_keyiv_len(&state->send_context) != (int)slen ||
2582: cipher_get_keyiv_len(&state->receive_context) != (int)rlen)
2583: return SSH_ERR_INVALID_FORMAT;
2584: if ((r = cipher_set_keyiv(&state->send_context, ivout)) != 0 ||
2585: (r = cipher_set_keyiv(&state->receive_context, ivin)) != 0)
2586: return r;
2587: } else {
2588: if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2589: (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2590: (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
1.224 dtucker 2591: (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
1.208 markus 2592: (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
1.201 markus 2593: (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2594: (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2595: (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2596: (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2597: (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2598: (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2599: (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2600: (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2601: return r;
1.208 markus 2602: /*
2603: * We set the time here so that in post-auth privsep slave we
2604: * count from the completion of the authentication.
2605: */
2606: state->rekey_time = monotime();
1.201 markus 2607: /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2608: if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2609: (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2610: return r;
2611: }
2612: if ((r = sshbuf_get_string_direct(m, &keyout, &slen)) != 0 ||
2613: (r = sshbuf_get_string_direct(m, &keyin, &rlen)) != 0)
2614: return r;
2615: if (cipher_get_keycontext(&state->send_context, NULL) != (int)slen ||
2616: cipher_get_keycontext(&state->receive_context, NULL) != (int)rlen)
2617: return SSH_ERR_INVALID_FORMAT;
2618: cipher_set_keycontext(&state->send_context, keyout);
2619: cipher_set_keycontext(&state->receive_context, keyin);
2620:
2621: if ((r = ssh_packet_set_compress_state(ssh, m)) != 0 ||
2622: (r = ssh_packet_set_postauth(ssh)) != 0)
2623: return r;
2624:
2625: sshbuf_reset(state->input);
2626: sshbuf_reset(state->output);
2627: if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2628: (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2629: (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2630: (r = sshbuf_put(state->output, output, olen)) != 0)
2631: return r;
2632:
2633: if (sshbuf_len(m))
2634: return SSH_ERR_INVALID_FORMAT;
2635: debug3("%s: done", __func__);
2636: return 0;
2637: }
2638:
2639: /* NEW API */
2640:
2641: /* put data to the outgoing packet */
2642:
2643: int
2644: sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2645: {
2646: return sshbuf_put(ssh->state->outgoing_packet, v, len);
2647: }
2648:
2649: int
2650: sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2651: {
2652: return sshbuf_putb(ssh->state->outgoing_packet, b);
2653: }
2654:
2655: int
2656: sshpkt_put_u8(struct ssh *ssh, u_char val)
2657: {
2658: return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2659: }
2660:
2661: int
2662: sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2663: {
2664: return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2665: }
2666:
2667: int
2668: sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2669: {
2670: return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2671: }
2672:
2673: int
2674: sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2675: {
2676: return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2677: }
2678:
2679: int
2680: sshpkt_put_cstring(struct ssh *ssh, const void *v)
2681: {
2682: return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2683: }
2684:
2685: int
2686: sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2687: {
2688: return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2689: }
2690:
1.211 djm 2691: #ifdef WITH_OPENSSL
1.201 markus 2692: int
2693: sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2694: {
2695: return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2696: }
2697:
1.211 djm 2698: #ifdef WITH_SSH1
1.201 markus 2699: int
2700: sshpkt_put_bignum1(struct ssh *ssh, const BIGNUM *v)
2701: {
2702: return sshbuf_put_bignum1(ssh->state->outgoing_packet, v);
2703: }
1.211 djm 2704: #endif /* WITH_SSH1 */
1.201 markus 2705:
2706: int
2707: sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2708: {
2709: return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2710: }
1.211 djm 2711: #endif /* WITH_OPENSSL */
1.201 markus 2712:
2713: /* fetch data from the incoming packet */
2714:
2715: int
2716: sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2717: {
2718: return sshbuf_get(ssh->state->incoming_packet, valp, len);
2719: }
2720:
2721: int
2722: sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2723: {
2724: return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2725: }
2726:
2727: int
2728: sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2729: {
2730: return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2731: }
2732:
2733: int
2734: sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2735: {
2736: return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2737: }
2738:
2739: int
2740: sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2741: {
2742: return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2743: }
2744:
2745: int
2746: sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2747: {
2748: return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2749: }
2750:
2751: int
2752: sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2753: {
2754: return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2755: }
2756:
1.211 djm 2757: #ifdef WITH_OPENSSL
1.201 markus 2758: int
2759: sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2760: {
2761: return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2762: }
2763:
1.211 djm 2764: #ifdef WITH_SSH1
1.201 markus 2765: int
2766: sshpkt_get_bignum1(struct ssh *ssh, BIGNUM *v)
2767: {
2768: return sshbuf_get_bignum1(ssh->state->incoming_packet, v);
2769: }
1.211 djm 2770: #endif /* WITH_SSH1 */
1.201 markus 2771:
2772: int
2773: sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2774: {
2775: return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2776: }
1.211 djm 2777: #endif /* WITH_OPENSSL */
1.201 markus 2778:
2779: int
2780: sshpkt_get_end(struct ssh *ssh)
2781: {
2782: if (sshbuf_len(ssh->state->incoming_packet) > 0)
2783: return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2784: return 0;
2785: }
2786:
2787: const u_char *
2788: sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2789: {
2790: if (lenp != NULL)
2791: *lenp = sshbuf_len(ssh->state->incoming_packet);
2792: return sshbuf_ptr(ssh->state->incoming_packet);
2793: }
2794:
2795: /* start a new packet */
2796:
2797: int
2798: sshpkt_start(struct ssh *ssh, u_char type)
2799: {
2800: u_char buf[9];
2801: int len;
2802:
2803: DBG(debug("packet_start[%d]", type));
2804: len = compat20 ? 6 : 9;
2805: memset(buf, 0, len - 1);
2806: buf[len - 1] = type;
2807: sshbuf_reset(ssh->state->outgoing_packet);
2808: return sshbuf_put(ssh->state->outgoing_packet, buf, len);
2809: }
2810:
2811: /* send it */
2812:
2813: int
2814: sshpkt_send(struct ssh *ssh)
2815: {
2816: if (compat20)
2817: return ssh_packet_send2(ssh);
2818: else
2819: return ssh_packet_send1(ssh);
2820: }
2821:
2822: int
2823: sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2824: {
2825: char buf[1024];
2826: va_list args;
2827: int r;
2828:
2829: va_start(args, fmt);
2830: vsnprintf(buf, sizeof(buf), fmt, args);
2831: va_end(args);
2832:
2833: if (compat20) {
2834: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2835: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2836: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2837: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2838: (r = sshpkt_send(ssh)) != 0)
2839: return r;
2840: } else {
2841: if ((r = sshpkt_start(ssh, SSH_MSG_DISCONNECT)) != 0 ||
2842: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2843: (r = sshpkt_send(ssh)) != 0)
2844: return r;
1.166 andreas 2845: }
1.201 markus 2846: return 0;
2847: }
2848:
2849: /* roundup current message to pad bytes */
2850: int
2851: sshpkt_add_padding(struct ssh *ssh, u_char pad)
2852: {
2853: ssh->state->extra_pad = pad;
2854: return 0;
1.1 deraadt 2855: }
![[BACK]](/icons/back.gif){kind=icon}
Return to packet.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh