Annotation of src/usr.bin/ssh/packet.c, Revision 1.240
1.240 ! djm 1: /* $OpenBSD: packet.c,v 1.239 2016/09/28 16:33:07 djm Exp $ */
1.1 deraadt 2: /*
1.15 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.35 deraadt 6: * This file contains code implementing the packet protocol and communication
7: * with the other side. This same code is used both on client and server side.
1.29 markus 8: *
1.35 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
1.29 markus 14: *
1.25 markus 15: *
16: * SSH2 packet format added by Markus Friedl.
1.69 markus 17: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.25 markus 18: *
1.35 deraadt 19: * Redistribution and use in source and binary forms, with or without
20: * modification, are permitted provided that the following conditions
21: * are met:
22: * 1. Redistributions of source code must retain the above copyright
23: * notice, this list of conditions and the following disclaimer.
24: * 2. Redistributions in binary form must reproduce the above copyright
25: * notice, this list of conditions and the following disclaimer in the
26: * documentation and/or other materials provided with the distribution.
27: *
28: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
29: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
30: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
31: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
32: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
33: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
37: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.15 deraadt 38: */
1.1 deraadt 39:
1.142 deraadt 40: #include <sys/types.h>
1.105 markus 41: #include <sys/queue.h>
1.132 stevesk 42: #include <sys/socket.h>
1.138 stevesk 43: #include <sys/time.h>
1.132 stevesk 44: #include <netinet/in.h>
1.121 stevesk 45: #include <netinet/ip.h>
1.134 stevesk 46:
1.135 stevesk 47: #include <errno.h>
1.230 djm 48: #include <netdb.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. */
1.235 djm 118: struct sshcipher_ctx *receive_context;
1.1 deraadt 119:
1.161 andreas 120: /* Encryption context for sending data. Only used for encryption. */
1.235 djm 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;
1.234 markus 192: size_t packet_discard_mac_already;
1.201 markus 193: struct sshmac *packet_discard_mac;
1.71 markus 194:
1.161 andreas 195: /* Used in packet_read_poll2() */
196: u_int packlen;
1.159 markus 197:
1.165 andreas 198: /* Used in packet_send2 */
199: int rekeying;
200:
201: /* Used in packet_set_interactive */
202: int set_interactive_called;
203:
204: /* Used in packet_set_maxsize */
205: int set_maxsize_called;
206:
1.201 markus 207: /* One-off warning about weak ciphers */
208: int cipher_warning_done;
209:
210: /* SSH1 CRC compensation attack detector */
211: struct deattack_ctx deattack;
212:
1.161 andreas 213: TAILQ_HEAD(, packet) outgoing;
1.105 markus 214: };
1.161 andreas 215:
1.201 markus 216: struct ssh *
217: ssh_alloc_session_state(void)
1.161 andreas 218: {
1.201 markus 219: struct ssh *ssh = NULL;
220: struct session_state *state = NULL;
1.161 andreas 221:
1.201 markus 222: if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
223: (state = calloc(1, sizeof(*state))) == NULL ||
224: (state->input = sshbuf_new()) == NULL ||
225: (state->output = sshbuf_new()) == NULL ||
226: (state->outgoing_packet = sshbuf_new()) == NULL ||
227: (state->incoming_packet = sshbuf_new()) == NULL)
228: goto fail;
229: TAILQ_INIT(&state->outgoing);
1.202 markus 230: TAILQ_INIT(&ssh->private_keys);
231: TAILQ_INIT(&ssh->public_keys);
1.201 markus 232: state->connection_in = -1;
233: state->connection_out = -1;
234: state->max_packet_size = 32768;
235: state->packet_timeout_ms = -1;
236: state->p_send.packets = state->p_read.packets = 0;
237: state->initialized = 1;
238: /*
239: * ssh_packet_send2() needs to queue packets until
240: * we've done the initial key exchange.
241: */
242: state->rekeying = 1;
243: ssh->state = state;
244: return ssh;
245: fail:
246: if (state) {
247: sshbuf_free(state->input);
248: sshbuf_free(state->output);
249: sshbuf_free(state->incoming_packet);
250: sshbuf_free(state->outgoing_packet);
251: free(state);
252: }
253: free(ssh);
254: return NULL;
1.161 andreas 255: }
1.105 markus 256:
1.228 djm 257: /* Returns nonzero if rekeying is in progress */
258: int
259: ssh_packet_is_rekeying(struct ssh *ssh)
260: {
1.229 djm 261: return compat20 &&
262: (ssh->state->rekeying || (ssh->kex != NULL && ssh->kex->done == 0));
1.228 djm 263: }
264:
1.16 markus 265: /*
266: * Sets the descriptors used for communication. Disables encryption until
267: * packet_set_encryption_key is called.
268: */
1.201 markus 269: struct ssh *
270: ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
1.1 deraadt 271: {
1.201 markus 272: struct session_state *state;
273: const struct sshcipher *none = cipher_by_name("none");
1.197 djm 274: int r;
1.97 deraadt 275:
1.205 djm 276: if (none == NULL) {
277: error("%s: cannot load cipher 'none'", __func__);
278: return NULL;
279: }
1.201 markus 280: if (ssh == NULL)
281: ssh = ssh_alloc_session_state();
1.205 djm 282: if (ssh == NULL) {
283: error("%s: cound not allocate state", __func__);
284: return NULL;
285: }
1.201 markus 286: state = ssh->state;
287: state->connection_in = fd_in;
288: state->connection_out = fd_out;
289: if ((r = cipher_init(&state->send_context, none,
1.197 djm 290: (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
1.201 markus 291: (r = cipher_init(&state->receive_context, none,
1.205 djm 292: (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
293: error("%s: cipher_init failed: %s", __func__, ssh_err(r));
1.230 djm 294: free(ssh); /* XXX need ssh_free_session_state? */
1.205 djm 295: return NULL;
296: }
1.201 markus 297: state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
298: deattack_init(&state->deattack);
1.207 djm 299: /*
300: * Cache the IP address of the remote connection for use in error
301: * messages that might be generated after the connection has closed.
302: */
303: (void)ssh_remote_ipaddr(ssh);
1.201 markus 304: return ssh;
1.1 deraadt 305: }
306:
1.154 dtucker 307: void
1.201 markus 308: ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
1.154 dtucker 309: {
1.201 markus 310: struct session_state *state = ssh->state;
311:
1.174 djm 312: if (timeout <= 0 || count <= 0) {
1.201 markus 313: state->packet_timeout_ms = -1;
1.154 dtucker 314: return;
315: }
316: if ((INT_MAX / 1000) / count < timeout)
1.201 markus 317: state->packet_timeout_ms = INT_MAX;
1.154 dtucker 318: else
1.201 markus 319: state->packet_timeout_ms = timeout * count * 1000;
1.154 dtucker 320: }
321:
1.201 markus 322: int
323: ssh_packet_stop_discard(struct ssh *ssh)
1.159 markus 324: {
1.201 markus 325: struct session_state *state = ssh->state;
326: int r;
327:
328: if (state->packet_discard_mac) {
1.159 markus 329: char buf[1024];
1.234 markus 330: size_t dlen = PACKET_MAX_SIZE;
1.201 markus 331:
1.234 markus 332: if (dlen > state->packet_discard_mac_already)
333: dlen -= state->packet_discard_mac_already;
1.159 markus 334: memset(buf, 'a', sizeof(buf));
1.234 markus 335: while (sshbuf_len(state->incoming_packet) < dlen)
1.201 markus 336: if ((r = sshbuf_put(state->incoming_packet, buf,
337: sizeof(buf))) != 0)
338: return r;
339: (void) mac_compute(state->packet_discard_mac,
340: state->p_read.seqnr,
1.234 markus 341: sshbuf_ptr(state->incoming_packet), dlen,
1.201 markus 342: NULL, 0);
1.159 markus 343: }
1.220 djm 344: logit("Finished discarding for %.200s port %d",
345: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.201 markus 346: return SSH_ERR_MAC_INVALID;
1.159 markus 347: }
348:
1.201 markus 349: static int
350: ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
1.234 markus 351: struct sshmac *mac, size_t mac_already, u_int discard)
1.159 markus 352: {
1.201 markus 353: struct session_state *state = ssh->state;
354: int r;
355:
356: if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
357: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
358: return r;
359: return SSH_ERR_MAC_INVALID;
360: }
1.234 markus 361: /*
362: * Record number of bytes over which the mac has already
363: * been computed in order to minimize timing attacks.
364: */
365: if (mac && mac->enabled) {
1.201 markus 366: state->packet_discard_mac = mac;
1.234 markus 367: state->packet_discard_mac_already = mac_already;
368: }
369: if (sshbuf_len(state->input) >= discard)
370: return ssh_packet_stop_discard(ssh);
1.201 markus 371: state->packet_discard = discard - sshbuf_len(state->input);
372: return 0;
1.159 markus 373: }
374:
1.19 markus 375: /* Returns 1 if remote host is connected via socket, 0 if not. */
376:
377: int
1.201 markus 378: ssh_packet_connection_is_on_socket(struct ssh *ssh)
1.19 markus 379: {
1.201 markus 380: struct session_state *state = ssh->state;
1.19 markus 381: struct sockaddr_storage from, to;
382: socklen_t fromlen, tolen;
383:
1.230 djm 384: if (state->connection_in == -1 || state->connection_out == -1)
385: return 0;
386:
1.19 markus 387: /* filedescriptors in and out are the same, so it's a socket */
1.201 markus 388: if (state->connection_in == state->connection_out)
1.19 markus 389: return 1;
390: fromlen = sizeof(from);
391: memset(&from, 0, sizeof(from));
1.201 markus 392: if (getpeername(state->connection_in, (struct sockaddr *)&from,
1.161 andreas 393: &fromlen) < 0)
1.19 markus 394: return 0;
395: tolen = sizeof(to);
396: memset(&to, 0, sizeof(to));
1.201 markus 397: if (getpeername(state->connection_out, (struct sockaddr *)&to,
1.161 andreas 398: &tolen) < 0)
1.19 markus 399: return 0;
400: if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
401: return 0;
402: if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
403: return 0;
404: return 1;
405: }
406:
1.91 markus 407: void
1.201 markus 408: ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
1.91 markus 409: {
1.201 markus 410: if (ibytes)
411: *ibytes = ssh->state->p_read.bytes;
412: if (obytes)
413: *obytes = ssh->state->p_send.bytes;
1.91 markus 414: }
1.125 deraadt 415:
1.91 markus 416: int
1.201 markus 417: ssh_packet_connection_af(struct ssh *ssh)
1.19 markus 418: {
419: struct sockaddr_storage to;
1.21 deraadt 420: socklen_t tolen = sizeof(to);
1.19 markus 421:
422: memset(&to, 0, sizeof(to));
1.201 markus 423: if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
1.161 andreas 424: &tolen) < 0)
1.19 markus 425: return 0;
1.173 djm 426: return to.ss_family;
1.19 markus 427: }
428:
1.1 deraadt 429: /* Sets the connection into non-blocking mode. */
430:
1.2 provos 431: void
1.201 markus 432: ssh_packet_set_nonblocking(struct ssh *ssh)
1.1 deraadt 433: {
1.14 markus 434: /* Set the socket into non-blocking mode. */
1.201 markus 435: set_nonblock(ssh->state->connection_in);
1.14 markus 436:
1.201 markus 437: if (ssh->state->connection_out != ssh->state->connection_in)
438: set_nonblock(ssh->state->connection_out);
1.1 deraadt 439: }
440:
441: /* Returns the socket used for reading. */
442:
1.2 provos 443: int
1.201 markus 444: ssh_packet_get_connection_in(struct ssh *ssh)
1.1 deraadt 445: {
1.201 markus 446: return ssh->state->connection_in;
1.1 deraadt 447: }
448:
449: /* Returns the descriptor used for writing. */
450:
1.2 provos 451: int
1.201 markus 452: ssh_packet_get_connection_out(struct ssh *ssh)
1.1 deraadt 453: {
1.201 markus 454: return ssh->state->connection_out;
455: }
456:
457: /*
458: * Returns the IP-address of the remote host as a string. The returned
459: * string must not be freed.
460: */
461:
462: const char *
463: ssh_remote_ipaddr(struct ssh *ssh)
464: {
1.220 djm 465: const int sock = ssh->state->connection_in;
466:
1.201 markus 467: /* Check whether we have cached the ipaddr. */
1.220 djm 468: if (ssh->remote_ipaddr == NULL) {
469: if (ssh_packet_connection_is_on_socket(ssh)) {
470: ssh->remote_ipaddr = get_peer_ipaddr(sock);
1.230 djm 471: ssh->remote_port = get_peer_port(sock);
472: ssh->local_ipaddr = get_local_ipaddr(sock);
473: ssh->local_port = get_local_port(sock);
1.220 djm 474: } else {
475: ssh->remote_ipaddr = strdup("UNKNOWN");
1.230 djm 476: ssh->remote_port = 65535;
477: ssh->local_ipaddr = strdup("UNKNOWN");
478: ssh->local_port = 65535;
1.220 djm 479: }
480: }
1.201 markus 481: return ssh->remote_ipaddr;
1.1 deraadt 482: }
483:
1.220 djm 484: /* Returns the port number of the remote host. */
485:
486: int
487: ssh_remote_port(struct ssh *ssh)
488: {
489: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
490: return ssh->remote_port;
1.230 djm 491: }
492:
493: /*
494: * Returns the IP-address of the local host as a string. The returned
495: * string must not be freed.
496: */
497:
498: const char *
499: ssh_local_ipaddr(struct ssh *ssh)
500: {
501: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
502: return ssh->local_ipaddr;
503: }
504:
505: /* Returns the port number of the local host. */
506:
507: int
508: ssh_local_port(struct ssh *ssh)
509: {
510: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
511: return ssh->local_port;
1.220 djm 512: }
513:
1.1 deraadt 514: /* Closes the connection and clears and frees internal data structures. */
515:
1.2 provos 516: void
1.201 markus 517: ssh_packet_close(struct ssh *ssh)
1.1 deraadt 518: {
1.201 markus 519: struct session_state *state = ssh->state;
520: u_int mode;
521:
522: if (!state->initialized)
1.14 markus 523: return;
1.201 markus 524: state->initialized = 0;
525: if (state->connection_in == state->connection_out) {
526: shutdown(state->connection_out, SHUT_RDWR);
527: close(state->connection_out);
1.14 markus 528: } else {
1.201 markus 529: close(state->connection_in);
530: close(state->connection_out);
1.14 markus 531: }
1.201 markus 532: sshbuf_free(state->input);
533: sshbuf_free(state->output);
534: sshbuf_free(state->outgoing_packet);
535: sshbuf_free(state->incoming_packet);
536: for (mode = 0; mode < MODE_MAX; mode++)
537: kex_free_newkeys(state->newkeys[mode]);
538: if (state->compression_buffer) {
539: sshbuf_free(state->compression_buffer);
540: if (state->compression_out_started) {
541: z_streamp stream = &state->compression_out_stream;
542: debug("compress outgoing: "
543: "raw data %llu, compressed %llu, factor %.2f",
544: (unsigned long long)stream->total_in,
545: (unsigned long long)stream->total_out,
546: stream->total_in == 0 ? 0.0 :
547: (double) stream->total_out / stream->total_in);
548: if (state->compression_out_failures == 0)
549: deflateEnd(stream);
550: }
551: if (state->compression_in_started) {
552: z_streamp stream = &state->compression_out_stream;
553: debug("compress incoming: "
554: "raw data %llu, compressed %llu, factor %.2f",
555: (unsigned long long)stream->total_out,
556: (unsigned long long)stream->total_in,
557: stream->total_out == 0 ? 0.0 :
558: (double) stream->total_in / stream->total_out);
559: if (state->compression_in_failures == 0)
560: inflateEnd(stream);
561: }
1.14 markus 562: }
1.235 djm 563: cipher_free(state->send_context);
564: cipher_free(state->receive_context);
565: state->send_context = state->receive_context = NULL;
1.219 mmcc 566: free(ssh->remote_ipaddr);
567: ssh->remote_ipaddr = NULL;
1.201 markus 568: free(ssh->state);
569: ssh->state = NULL;
1.1 deraadt 570: }
571:
572: /* Sets remote side protocol flags. */
573:
1.2 provos 574: void
1.201 markus 575: ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
1.1 deraadt 576: {
1.201 markus 577: ssh->state->remote_protocol_flags = protocol_flags;
1.1 deraadt 578: }
579:
580: /* Returns the remote protocol flags set earlier by the above function. */
581:
1.40 markus 582: u_int
1.201 markus 583: ssh_packet_get_protocol_flags(struct ssh *ssh)
1.1 deraadt 584: {
1.201 markus 585: return ssh->state->remote_protocol_flags;
1.1 deraadt 586: }
587:
1.16 markus 588: /*
589: * Starts packet compression from the next packet on in both directions.
590: * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
591: */
1.1 deraadt 592:
1.201 markus 593: static int
594: ssh_packet_init_compression(struct ssh *ssh)
1.60 markus 595: {
1.201 markus 596: if (!ssh->state->compression_buffer &&
597: ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
598: return SSH_ERR_ALLOC_FAIL;
599: return 0;
1.60 markus 600: }
601:
1.201 markus 602: static int
603: start_compression_out(struct ssh *ssh, int level)
1.1 deraadt 604: {
1.201 markus 605: if (level < 1 || level > 9)
606: return SSH_ERR_INVALID_ARGUMENT;
607: debug("Enabling compression at level %d.", level);
608: if (ssh->state->compression_out_started == 1)
609: deflateEnd(&ssh->state->compression_out_stream);
610: switch (deflateInit(&ssh->state->compression_out_stream, level)) {
611: case Z_OK:
612: ssh->state->compression_out_started = 1;
613: break;
614: case Z_MEM_ERROR:
615: return SSH_ERR_ALLOC_FAIL;
616: default:
617: return SSH_ERR_INTERNAL_ERROR;
618: }
619: return 0;
1.1 deraadt 620: }
621:
1.201 markus 622: static int
623: start_compression_in(struct ssh *ssh)
624: {
625: if (ssh->state->compression_in_started == 1)
626: inflateEnd(&ssh->state->compression_in_stream);
627: switch (inflateInit(&ssh->state->compression_in_stream)) {
628: case Z_OK:
629: ssh->state->compression_in_started = 1;
630: break;
631: case Z_MEM_ERROR:
632: return SSH_ERR_ALLOC_FAIL;
633: default:
634: return SSH_ERR_INTERNAL_ERROR;
635: }
636: return 0;
637: }
1.95 markus 638:
1.201 markus 639: int
640: ssh_packet_start_compression(struct ssh *ssh, int level)
1.1 deraadt 641: {
1.197 djm 642: int r;
1.97 deraadt 643:
1.201 markus 644: if (ssh->state->packet_compression && !compat20)
645: return SSH_ERR_INTERNAL_ERROR;
646: ssh->state->packet_compression = 1;
647: if ((r = ssh_packet_init_compression(ssh)) != 0 ||
648: (r = start_compression_in(ssh)) != 0 ||
649: (r = start_compression_out(ssh, level)) != 0)
650: return r;
651: return 0;
1.95 markus 652: }
653:
1.201 markus 654: /* XXX remove need for separate compression buffer */
655: static int
656: compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.95 markus 657: {
1.201 markus 658: u_char buf[4096];
659: int r, status;
660:
661: if (ssh->state->compression_out_started != 1)
662: return SSH_ERR_INTERNAL_ERROR;
663:
664: /* This case is not handled below. */
665: if (sshbuf_len(in) == 0)
666: return 0;
667:
668: /* Input is the contents of the input buffer. */
669: if ((ssh->state->compression_out_stream.next_in =
670: sshbuf_mutable_ptr(in)) == NULL)
671: return SSH_ERR_INTERNAL_ERROR;
672: ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
673:
674: /* Loop compressing until deflate() returns with avail_out != 0. */
675: do {
676: /* Set up fixed-size output buffer. */
677: ssh->state->compression_out_stream.next_out = buf;
678: ssh->state->compression_out_stream.avail_out = sizeof(buf);
679:
680: /* Compress as much data into the buffer as possible. */
681: status = deflate(&ssh->state->compression_out_stream,
682: Z_PARTIAL_FLUSH);
683: switch (status) {
684: case Z_MEM_ERROR:
685: return SSH_ERR_ALLOC_FAIL;
686: case Z_OK:
687: /* Append compressed data to output_buffer. */
688: if ((r = sshbuf_put(out, buf, sizeof(buf) -
689: ssh->state->compression_out_stream.avail_out)) != 0)
690: return r;
691: break;
692: case Z_STREAM_ERROR:
693: default:
694: ssh->state->compression_out_failures++;
695: return SSH_ERR_INVALID_FORMAT;
696: }
697: } while (ssh->state->compression_out_stream.avail_out == 0);
698: return 0;
1.1 deraadt 699: }
700:
1.201 markus 701: static int
702: uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.1 deraadt 703: {
1.201 markus 704: u_char buf[4096];
705: int r, status;
1.1 deraadt 706:
1.201 markus 707: if (ssh->state->compression_in_started != 1)
708: return SSH_ERR_INTERNAL_ERROR;
1.25 markus 709:
1.201 markus 710: if ((ssh->state->compression_in_stream.next_in =
711: sshbuf_mutable_ptr(in)) == NULL)
712: return SSH_ERR_INTERNAL_ERROR;
713: ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
1.97 deraadt 714:
1.201 markus 715: for (;;) {
716: /* Set up fixed-size output buffer. */
717: ssh->state->compression_in_stream.next_out = buf;
718: ssh->state->compression_in_stream.avail_out = sizeof(buf);
719:
720: status = inflate(&ssh->state->compression_in_stream,
721: Z_PARTIAL_FLUSH);
722: switch (status) {
723: case Z_OK:
724: if ((r = sshbuf_put(out, buf, sizeof(buf) -
725: ssh->state->compression_in_stream.avail_out)) != 0)
726: return r;
727: break;
728: case Z_BUF_ERROR:
729: /*
730: * Comments in zlib.h say that we should keep calling
731: * inflate() until we get an error. This appears to
732: * be the error that we get.
733: */
734: return 0;
735: case Z_DATA_ERROR:
736: return SSH_ERR_INVALID_FORMAT;
737: case Z_MEM_ERROR:
738: return SSH_ERR_ALLOC_FAIL;
739: case Z_STREAM_ERROR:
740: default:
741: ssh->state->compression_in_failures++;
742: return SSH_ERR_INTERNAL_ERROR;
743: }
744: }
745: /* NOTREACHED */
1.1 deraadt 746: }
1.125 deraadt 747:
1.201 markus 748: /*
749: * Causes any further packets to be encrypted using the given key. The same
750: * key is used for both sending and reception. However, both directions are
751: * encrypted independently of each other.
752: */
1.125 deraadt 753:
1.2 provos 754: void
1.201 markus 755: ssh_packet_set_encryption_key(struct ssh *ssh, const u_char *key, u_int keylen, int number)
1.1 deraadt 756: {
1.211 djm 757: #ifndef WITH_SSH1
758: fatal("no SSH protocol 1 support");
759: #else /* WITH_SSH1 */
1.201 markus 760: struct session_state *state = ssh->state;
761: const struct sshcipher *cipher = cipher_by_number(number);
762: int r;
763: const char *wmsg;
1.125 deraadt 764:
1.201 markus 765: if (cipher == NULL)
766: fatal("%s: unknown cipher number %d", __func__, number);
767: if (keylen < 20)
768: fatal("%s: keylen too small: %d", __func__, keylen);
769: if (keylen > SSH_SESSION_KEY_LENGTH)
770: fatal("%s: keylen too big: %d", __func__, keylen);
771: memcpy(state->ssh1_key, key, keylen);
772: state->ssh1_keylen = keylen;
773: if ((r = cipher_init(&state->send_context, cipher, key, keylen,
774: NULL, 0, CIPHER_ENCRYPT)) != 0 ||
775: (r = cipher_init(&state->receive_context, cipher, key, keylen,
776: NULL, 0, CIPHER_DECRYPT) != 0))
777: fatal("%s: cipher_init failed: %s", __func__, ssh_err(r));
778: if (!state->cipher_warning_done &&
1.235 djm 779: ((wmsg = cipher_warning_message(state->send_context)) != NULL ||
780: (wmsg = cipher_warning_message(state->send_context)) != NULL)) {
1.201 markus 781: error("Warning: %s", wmsg);
782: state->cipher_warning_done = 1;
783: }
1.211 djm 784: #endif /* WITH_SSH1 */
1.170 djm 785: }
786:
1.16 markus 787: /*
788: * Finalizes and sends the packet. If the encryption key has been set,
789: * encrypts the packet before sending.
790: */
1.14 markus 791:
1.201 markus 792: int
793: ssh_packet_send1(struct ssh *ssh)
1.1 deraadt 794: {
1.201 markus 795: struct session_state *state = ssh->state;
1.89 markus 796: u_char buf[8], *cp;
1.201 markus 797: int r, padding, len;
1.40 markus 798: u_int checksum;
1.14 markus 799:
1.16 markus 800: /*
801: * If using packet compression, compress the payload of the outgoing
802: * packet.
803: */
1.201 markus 804: if (state->packet_compression) {
805: sshbuf_reset(state->compression_buffer);
1.14 markus 806: /* Skip padding. */
1.201 markus 807: if ((r = sshbuf_consume(state->outgoing_packet, 8)) != 0)
808: goto out;
1.14 markus 809: /* padding */
1.201 markus 810: if ((r = sshbuf_put(state->compression_buffer,
811: "\0\0\0\0\0\0\0\0", 8)) != 0)
812: goto out;
813: if ((r = compress_buffer(ssh, state->outgoing_packet,
814: state->compression_buffer)) != 0)
815: goto out;
816: sshbuf_reset(state->outgoing_packet);
817: if ((r = sshbuf_putb(state->outgoing_packet,
818: state->compression_buffer)) != 0)
819: goto out;
1.14 markus 820: }
821: /* Compute packet length without padding (add checksum, remove padding). */
1.201 markus 822: len = sshbuf_len(state->outgoing_packet) + 4 - 8;
1.14 markus 823:
1.32 markus 824: /* Insert padding. Initialized to zero in packet_start1() */
1.14 markus 825: padding = 8 - len % 8;
1.235 djm 826: if (!cipher_ctx_is_plaintext(state->send_context)) {
1.201 markus 827: cp = sshbuf_mutable_ptr(state->outgoing_packet);
828: if (cp == NULL) {
829: r = SSH_ERR_INTERNAL_ERROR;
830: goto out;
1.14 markus 831: }
1.201 markus 832: arc4random_buf(cp + 8 - padding, padding);
1.14 markus 833: }
1.201 markus 834: if ((r = sshbuf_consume(state->outgoing_packet, 8 - padding)) != 0)
835: goto out;
1.14 markus 836:
837: /* Add check bytes. */
1.201 markus 838: checksum = ssh_crc32(sshbuf_ptr(state->outgoing_packet),
839: sshbuf_len(state->outgoing_packet));
840: POKE_U32(buf, checksum);
841: if ((r = sshbuf_put(state->outgoing_packet, buf, 4)) != 0)
842: goto out;
1.1 deraadt 843:
844: #ifdef PACKET_DEBUG
1.14 markus 845: fprintf(stderr, "packet_send plain: ");
1.201 markus 846: sshbuf_dump(state->outgoing_packet, stderr);
1.1 deraadt 847: #endif
848:
1.14 markus 849: /* Append to output. */
1.201 markus 850: POKE_U32(buf, len);
851: if ((r = sshbuf_put(state->output, buf, 4)) != 0)
852: goto out;
853: if ((r = sshbuf_reserve(state->output,
854: sshbuf_len(state->outgoing_packet), &cp)) != 0)
855: goto out;
1.235 djm 856: if ((r = cipher_crypt(state->send_context, 0, cp,
1.201 markus 857: sshbuf_ptr(state->outgoing_packet),
858: sshbuf_len(state->outgoing_packet), 0, 0)) != 0)
859: goto out;
1.14 markus 860:
1.1 deraadt 861: #ifdef PACKET_DEBUG
1.14 markus 862: fprintf(stderr, "encrypted: ");
1.201 markus 863: sshbuf_dump(state->output, stderr);
1.1 deraadt 864: #endif
1.201 markus 865: state->p_send.packets++;
866: state->p_send.bytes += len +
867: sshbuf_len(state->outgoing_packet);
868: sshbuf_reset(state->outgoing_packet);
1.1 deraadt 869:
1.16 markus 870: /*
1.120 djm 871: * Note that the packet is now only buffered in output. It won't be
1.205 djm 872: * actually sent until ssh_packet_write_wait or ssh_packet_write_poll
873: * is called.
1.16 markus 874: */
1.201 markus 875: r = 0;
876: out:
877: return r;
1.1 deraadt 878: }
879:
1.201 markus 880: int
881: ssh_set_newkeys(struct ssh *ssh, int mode)
1.57 markus 882: {
1.201 markus 883: struct session_state *state = ssh->state;
884: struct sshenc *enc;
885: struct sshmac *mac;
886: struct sshcomp *comp;
1.235 djm 887: struct sshcipher_ctx **ccp;
1.236 markus 888: struct packet_state *ps;
1.105 markus 889: u_int64_t *max_blocks;
1.236 markus 890: const char *wmsg, *dir;
1.197 djm 891: int r, crypt_type;
1.57 markus 892:
1.100 markus 893: debug2("set_newkeys: mode %d", mode);
1.57 markus 894:
1.88 markus 895: if (mode == MODE_OUT) {
1.236 markus 896: dir = "output";
1.235 djm 897: ccp = &state->send_context;
1.115 avsm 898: crypt_type = CIPHER_ENCRYPT;
1.236 markus 899: ps = &state->p_send;
1.201 markus 900: max_blocks = &state->max_blocks_out;
1.88 markus 901: } else {
1.236 markus 902: dir = "input";
1.235 djm 903: ccp = &state->receive_context;
1.115 avsm 904: crypt_type = CIPHER_DECRYPT;
1.236 markus 905: ps = &state->p_read;
1.201 markus 906: max_blocks = &state->max_blocks_in;
1.88 markus 907: }
1.201 markus 908: if (state->newkeys[mode] != NULL) {
1.236 markus 909: debug("%s: rekeying after %llu %s blocks"
910: " (%llu bytes total)", __func__,
911: (unsigned long long)ps->blocks, dir,
912: (unsigned long long)ps->bytes);
1.235 djm 913: cipher_free(*ccp);
914: *ccp = NULL;
1.201 markus 915: enc = &state->newkeys[mode]->enc;
916: mac = &state->newkeys[mode]->mac;
917: comp = &state->newkeys[mode]->comp;
1.148 pvalchev 918: mac_clear(mac);
1.192 djm 919: explicit_bzero(enc->iv, enc->iv_len);
920: explicit_bzero(enc->key, enc->key_len);
921: explicit_bzero(mac->key, mac->key_len);
1.186 djm 922: free(enc->name);
923: free(enc->iv);
924: free(enc->key);
925: free(mac->name);
926: free(mac->key);
927: free(comp->name);
1.201 markus 928: free(state->newkeys[mode]);
1.57 markus 929: }
1.236 markus 930: /* note that both bytes and the seqnr are not reset */
931: ps->packets = ps->blocks = 0;
1.201 markus 932: /* move newkeys from kex to state */
933: if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
934: return SSH_ERR_INTERNAL_ERROR;
935: ssh->kex->newkeys[mode] = NULL;
936: enc = &state->newkeys[mode]->enc;
937: mac = &state->newkeys[mode]->mac;
938: comp = &state->newkeys[mode]->comp;
939: if (cipher_authlen(enc->cipher) == 0) {
940: if ((r = mac_init(mac)) != 0)
941: return r;
942: }
943: mac->enabled = 1;
1.57 markus 944: DBG(debug("cipher_init_context: %d", mode));
1.235 djm 945: if ((r = cipher_init(ccp, enc->cipher, enc->key, enc->key_len,
1.197 djm 946: enc->iv, enc->iv_len, crypt_type)) != 0)
1.201 markus 947: return r;
948: if (!state->cipher_warning_done &&
1.235 djm 949: (wmsg = cipher_warning_message(*ccp)) != NULL) {
1.201 markus 950: error("Warning: %s", wmsg);
951: state->cipher_warning_done = 1;
952: }
1.91 markus 953: /* Deleting the keys does not gain extra security */
1.192 djm 954: /* explicit_bzero(enc->iv, enc->block_size);
955: explicit_bzero(enc->key, enc->key_len);
956: explicit_bzero(mac->key, mac->key_len); */
1.240 ! djm 957: if (comp->type == COMP_DELAYED && state->after_authentication &&
! 958: comp->enabled == 0) {
1.201 markus 959: if ((r = ssh_packet_init_compression(ssh)) < 0)
960: return r;
961: if (mode == MODE_OUT) {
962: if ((r = start_compression_out(ssh, 6)) != 0)
963: return r;
964: } else {
965: if ((r = start_compression_in(ssh)) != 0)
966: return r;
967: }
1.57 markus 968: comp->enabled = 1;
969: }
1.109 markus 970: /*
971: * The 2^(blocksize*2) limit is too expensive for 3DES,
972: * blowfish, etc, so enforce a 1GB limit for small blocksizes.
973: */
974: if (enc->block_size >= 16)
975: *max_blocks = (u_int64_t)1 << (enc->block_size*2);
976: else
977: *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1.201 markus 978: if (state->rekey_limit)
1.237 deraadt 979: *max_blocks = MINIMUM(*max_blocks,
1.201 markus 980: state->rekey_limit / enc->block_size);
1.227 djm 981: debug("rekey after %llu blocks", (unsigned long long)*max_blocks);
1.201 markus 982: return 0;
1.57 markus 983: }
984:
1.228 djm 985: #define MAX_PACKETS (1U<<31)
986: static int
987: ssh_packet_need_rekeying(struct ssh *ssh, u_int outbound_packet_len)
988: {
989: struct session_state *state = ssh->state;
990: u_int32_t out_blocks;
991:
992: /* XXX client can't cope with rekeying pre-auth */
993: if (!state->after_authentication)
994: return 0;
995:
996: /* Haven't keyed yet or KEX in progress. */
997: if (ssh->kex == NULL || ssh_packet_is_rekeying(ssh))
998: return 0;
999:
1000: /* Peer can't rekey */
1001: if (ssh->compat & SSH_BUG_NOREKEY)
1002: return 0;
1003:
1004: /*
1005: * Permit one packet in or out per rekey - this allows us to
1006: * make progress when rekey limits are very small.
1007: */
1008: if (state->p_send.packets == 0 && state->p_read.packets == 0)
1009: return 0;
1010:
1011: /* Time-based rekeying */
1012: if (state->rekey_interval != 0 &&
1013: state->rekey_time + state->rekey_interval <= monotime())
1014: return 1;
1015:
1016: /* Always rekey when MAX_PACKETS sent in either direction */
1017: if (state->p_send.packets > MAX_PACKETS ||
1018: state->p_read.packets > MAX_PACKETS)
1019: return 1;
1020:
1021: /* Rekey after (cipher-specific) maxiumum blocks */
1.237 deraadt 1022: out_blocks = ROUNDUP(outbound_packet_len,
1.228 djm 1023: state->newkeys[MODE_OUT]->enc.block_size);
1024: return (state->max_blocks_out &&
1025: (state->p_send.blocks + out_blocks > state->max_blocks_out)) ||
1026: (state->max_blocks_in &&
1027: (state->p_read.blocks > state->max_blocks_in));
1028: }
1029:
1.16 markus 1030: /*
1.118 markus 1031: * Delayed compression for SSH2 is enabled after authentication:
1.143 dtucker 1032: * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1.118 markus 1033: * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
1034: */
1.201 markus 1035: static int
1036: ssh_packet_enable_delayed_compress(struct ssh *ssh)
1.118 markus 1037: {
1.201 markus 1038: struct session_state *state = ssh->state;
1039: struct sshcomp *comp = NULL;
1040: int r, mode;
1.118 markus 1041:
1042: /*
1043: * Remember that we are past the authentication step, so rekeying
1044: * with COMP_DELAYED will turn on compression immediately.
1045: */
1.201 markus 1046: state->after_authentication = 1;
1.118 markus 1047: for (mode = 0; mode < MODE_MAX; mode++) {
1.145 markus 1048: /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1.201 markus 1049: if (state->newkeys[mode] == NULL)
1.145 markus 1050: continue;
1.201 markus 1051: comp = &state->newkeys[mode]->comp;
1.118 markus 1052: if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1.201 markus 1053: if ((r = ssh_packet_init_compression(ssh)) != 0)
1054: return r;
1055: if (mode == MODE_OUT) {
1056: if ((r = start_compression_out(ssh, 6)) != 0)
1057: return r;
1058: } else {
1059: if ((r = start_compression_in(ssh)) != 0)
1060: return r;
1061: }
1.118 markus 1062: comp->enabled = 1;
1063: }
1064: }
1.201 markus 1065: return 0;
1.118 markus 1066: }
1067:
1.226 djm 1068: /* Used to mute debug logging for noisy packet types */
1069: static int
1070: ssh_packet_log_type(u_char type)
1071: {
1072: switch (type) {
1073: case SSH2_MSG_CHANNEL_DATA:
1074: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1075: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1076: return 0;
1077: default:
1078: return 1;
1079: }
1080: }
1081:
1.118 markus 1082: /*
1.25 markus 1083: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1084: */
1.201 markus 1085: int
1086: ssh_packet_send2_wrapped(struct ssh *ssh)
1.25 markus 1087: {
1.201 markus 1088: struct session_state *state = ssh->state;
1.200 markus 1089: u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1.233 djm 1090: u_char tmp, padlen, pad = 0;
1.201 markus 1091: u_int authlen = 0, aadlen = 0;
1092: u_int len;
1093: struct sshenc *enc = NULL;
1094: struct sshmac *mac = NULL;
1095: struct sshcomp *comp = NULL;
1096: int r, block_size;
1097:
1098: if (state->newkeys[MODE_OUT] != NULL) {
1099: enc = &state->newkeys[MODE_OUT]->enc;
1100: mac = &state->newkeys[MODE_OUT]->mac;
1101: comp = &state->newkeys[MODE_OUT]->comp;
1.180 markus 1102: /* disable mac for authenticated encryption */
1103: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1104: mac = NULL;
1.25 markus 1105: }
1.88 markus 1106: block_size = enc ? enc->block_size : 8;
1.180 markus 1107: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1108:
1.201 markus 1109: type = (sshbuf_ptr(state->outgoing_packet))[5];
1.226 djm 1110: if (ssh_packet_log_type(type))
1111: debug3("send packet: type %u", type);
1.25 markus 1112: #ifdef PACKET_DEBUG
1113: fprintf(stderr, "plain: ");
1.201 markus 1114: sshbuf_dump(state->outgoing_packet, stderr);
1.25 markus 1115: #endif
1116:
1117: if (comp && comp->enabled) {
1.201 markus 1118: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1119: /* skip header, compress only payload */
1.201 markus 1120: if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1121: goto out;
1122: sshbuf_reset(state->compression_buffer);
1123: if ((r = compress_buffer(ssh, state->outgoing_packet,
1124: state->compression_buffer)) != 0)
1125: goto out;
1126: sshbuf_reset(state->outgoing_packet);
1127: if ((r = sshbuf_put(state->outgoing_packet,
1128: "\0\0\0\0\0", 5)) != 0 ||
1129: (r = sshbuf_putb(state->outgoing_packet,
1130: state->compression_buffer)) != 0)
1131: goto out;
1132: DBG(debug("compression: raw %d compressed %zd", len,
1133: sshbuf_len(state->outgoing_packet)));
1.25 markus 1134: }
1135:
1136: /* sizeof (packet_len + pad_len + payload) */
1.201 markus 1137: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1138:
1139: /*
1140: * calc size of padding, alloc space, get random data,
1141: * minimum padding is 4 bytes
1142: */
1.178 markus 1143: len -= aadlen; /* packet length is not encrypted for EtM modes */
1.25 markus 1144: padlen = block_size - (len % block_size);
1145: if (padlen < 4)
1146: padlen += block_size;
1.201 markus 1147: if (state->extra_pad) {
1.233 djm 1148: tmp = state->extra_pad;
1.201 markus 1149: state->extra_pad =
1.237 deraadt 1150: ROUNDUP(state->extra_pad, block_size);
1.233 djm 1151: /* check if roundup overflowed */
1152: if (state->extra_pad < tmp)
1153: return SSH_ERR_INVALID_ARGUMENT;
1154: tmp = (len + padlen) % state->extra_pad;
1155: /* Check whether pad calculation below will underflow */
1156: if (tmp > state->extra_pad)
1157: return SSH_ERR_INVALID_ARGUMENT;
1158: pad = state->extra_pad - tmp;
1.193 djm 1159: DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1.201 markus 1160: __func__, pad, len, padlen, state->extra_pad));
1.233 djm 1161: tmp = padlen;
1.71 markus 1162: padlen += pad;
1.233 djm 1163: /* Check whether padlen calculation overflowed */
1164: if (padlen < tmp)
1165: return SSH_ERR_INVALID_ARGUMENT; /* overflow */
1.201 markus 1166: state->extra_pad = 0;
1.71 markus 1167: }
1.201 markus 1168: if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1169: goto out;
1.235 djm 1170: if (enc && !cipher_ctx_is_plaintext(state->send_context)) {
1.32 markus 1171: /* random padding */
1.201 markus 1172: arc4random_buf(cp, padlen);
1.32 markus 1173: } else {
1174: /* clear padding */
1.192 djm 1175: explicit_bzero(cp, padlen);
1.25 markus 1176: }
1.178 markus 1177: /* sizeof (packet_len + pad_len + payload + padding) */
1.201 markus 1178: len = sshbuf_len(state->outgoing_packet);
1179: cp = sshbuf_mutable_ptr(state->outgoing_packet);
1180: if (cp == NULL) {
1181: r = SSH_ERR_INTERNAL_ERROR;
1182: goto out;
1183: }
1.25 markus 1184: /* packet_length includes payload, padding and padding length field */
1.201 markus 1185: POKE_U32(cp, len - 4);
1.89 markus 1186: cp[4] = padlen;
1.178 markus 1187: DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1188: len, padlen, aadlen));
1.25 markus 1189:
1190: /* compute MAC over seqnr and packet(length fields, payload, padding) */
1.178 markus 1191: if (mac && mac->enabled && !mac->etm) {
1.201 markus 1192: if ((r = mac_compute(mac, state->p_send.seqnr,
1193: sshbuf_ptr(state->outgoing_packet), len,
1.200 markus 1194: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1195: goto out;
1196: DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1.25 markus 1197: }
1198: /* encrypt packet and append to output buffer. */
1.201 markus 1199: if ((r = sshbuf_reserve(state->output,
1200: sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1201: goto out;
1.235 djm 1202: if ((r = cipher_crypt(state->send_context, state->p_send.seqnr, cp,
1.201 markus 1203: sshbuf_ptr(state->outgoing_packet),
1204: len - aadlen, aadlen, authlen)) != 0)
1205: goto out;
1.25 markus 1206: /* append unencrypted MAC */
1.178 markus 1207: if (mac && mac->enabled) {
1208: if (mac->etm) {
1209: /* EtM: compute mac over aadlen + cipher text */
1.201 markus 1210: if ((r = mac_compute(mac, state->p_send.seqnr,
1211: cp, len, macbuf, sizeof(macbuf))) != 0)
1212: goto out;
1.178 markus 1213: DBG(debug("done calc MAC(EtM) out #%d",
1.201 markus 1214: state->p_send.seqnr));
1.178 markus 1215: }
1.201 markus 1216: if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1217: goto out;
1.178 markus 1218: }
1.25 markus 1219: #ifdef PACKET_DEBUG
1220: fprintf(stderr, "encrypted: ");
1.201 markus 1221: sshbuf_dump(state->output, stderr);
1.25 markus 1222: #endif
1.29 markus 1223: /* increment sequence number for outgoing packets */
1.201 markus 1224: if (++state->p_send.seqnr == 0)
1.106 itojun 1225: logit("outgoing seqnr wraps around");
1.201 markus 1226: if (++state->p_send.packets == 0)
1227: if (!(ssh->compat & SSH_BUG_NOREKEY))
1228: return SSH_ERR_NEED_REKEY;
1229: state->p_send.blocks += len / block_size;
1230: state->p_send.bytes += len;
1231: sshbuf_reset(state->outgoing_packet);
1.25 markus 1232:
1.57 markus 1233: if (type == SSH2_MSG_NEWKEYS)
1.201 markus 1234: r = ssh_set_newkeys(ssh, MODE_OUT);
1235: else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1236: r = ssh_packet_enable_delayed_compress(ssh);
1237: else
1238: r = 0;
1239: out:
1240: return r;
1.25 markus 1241: }
1242:
1.228 djm 1243: /* returns non-zero if the specified packet type is usec by KEX */
1244: static int
1245: ssh_packet_type_is_kex(u_char type)
1246: {
1247: return
1248: type >= SSH2_MSG_TRANSPORT_MIN &&
1249: type <= SSH2_MSG_TRANSPORT_MAX &&
1250: type != SSH2_MSG_SERVICE_REQUEST &&
1251: type != SSH2_MSG_SERVICE_ACCEPT &&
1252: type != SSH2_MSG_EXT_INFO;
1253: }
1254:
1.201 markus 1255: int
1256: ssh_packet_send2(struct ssh *ssh)
1.105 markus 1257: {
1.201 markus 1258: struct session_state *state = ssh->state;
1.105 markus 1259: struct packet *p;
1.201 markus 1260: u_char type;
1.228 djm 1261: int r, need_rekey;
1.105 markus 1262:
1.228 djm 1263: if (sshbuf_len(state->outgoing_packet) < 6)
1264: return SSH_ERR_INTERNAL_ERROR;
1.201 markus 1265: type = sshbuf_ptr(state->outgoing_packet)[5];
1.228 djm 1266: need_rekey = !ssh_packet_type_is_kex(type) &&
1267: ssh_packet_need_rekeying(ssh, sshbuf_len(state->outgoing_packet));
1.105 markus 1268:
1.228 djm 1269: /*
1270: * During rekeying we can only send key exchange messages.
1271: * Queue everything else.
1272: */
1273: if ((need_rekey || state->rekeying) && !ssh_packet_type_is_kex(type)) {
1274: if (need_rekey)
1275: debug3("%s: rekex triggered", __func__);
1276: debug("enqueue packet: %u", type);
1277: p = calloc(1, sizeof(*p));
1278: if (p == NULL)
1279: return SSH_ERR_ALLOC_FAIL;
1280: p->type = type;
1281: p->payload = state->outgoing_packet;
1282: TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1283: state->outgoing_packet = sshbuf_new();
1284: if (state->outgoing_packet == NULL)
1285: return SSH_ERR_ALLOC_FAIL;
1286: if (need_rekey) {
1287: /*
1288: * This packet triggered a rekey, so send the
1289: * KEXINIT now.
1290: * NB. reenters this function via kex_start_rekex().
1291: */
1292: return kex_start_rekex(ssh);
1.105 markus 1293: }
1.228 djm 1294: return 0;
1.105 markus 1295: }
1296:
1297: /* rekeying starts with sending KEXINIT */
1298: if (type == SSH2_MSG_KEXINIT)
1.201 markus 1299: state->rekeying = 1;
1.105 markus 1300:
1.201 markus 1301: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1302: return r;
1.105 markus 1303:
1304: /* after a NEWKEYS message we can send the complete queue */
1305: if (type == SSH2_MSG_NEWKEYS) {
1.201 markus 1306: state->rekeying = 0;
1307: state->rekey_time = monotime();
1308: while ((p = TAILQ_FIRST(&state->outgoing))) {
1.105 markus 1309: type = p->type;
1.228 djm 1310: /*
1311: * If this packet triggers a rekex, then skip the
1312: * remaining packets in the queue for now.
1313: * NB. re-enters this function via kex_start_rekex.
1314: */
1315: if (ssh_packet_need_rekeying(ssh,
1316: sshbuf_len(p->payload))) {
1317: debug3("%s: queued packet triggered rekex",
1318: __func__);
1319: return kex_start_rekex(ssh);
1320: }
1.105 markus 1321: debug("dequeue packet: %u", type);
1.201 markus 1322: sshbuf_free(state->outgoing_packet);
1323: state->outgoing_packet = p->payload;
1324: TAILQ_REMOVE(&state->outgoing, p, next);
1.228 djm 1325: memset(p, 0, sizeof(*p));
1.186 djm 1326: free(p);
1.201 markus 1327: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1328: return r;
1.105 markus 1329: }
1330: }
1.201 markus 1331: return 0;
1.25 markus 1332: }
1333:
1334: /*
1.16 markus 1335: * Waits until a packet has been received, and returns its type. Note that
1336: * no other data is processed until this returns, so this function should not
1337: * be used during the interactive session.
1338: */
1.1 deraadt 1339:
1.2 provos 1340: int
1.201 markus 1341: ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.1 deraadt 1342: {
1.201 markus 1343: struct session_state *state = ssh->state;
1.222 markus 1344: int len, r, ms_remain;
1.56 millert 1345: fd_set *setp;
1.14 markus 1346: char buf[8192];
1.155 deraadt 1347: struct timeval timeout, start, *timeoutp = NULL;
1348:
1.25 markus 1349: DBG(debug("packet_read()"));
1.14 markus 1350:
1.214 deraadt 1351: setp = calloc(howmany(state->connection_in + 1,
1.161 andreas 1352: NFDBITS), sizeof(fd_mask));
1.201 markus 1353: if (setp == NULL)
1354: return SSH_ERR_ALLOC_FAIL;
1.56 millert 1355:
1.205 djm 1356: /*
1357: * Since we are blocking, ensure that all written packets have
1358: * been sent.
1359: */
1.210 markus 1360: if ((r = ssh_packet_write_wait(ssh)) != 0)
1361: goto out;
1.14 markus 1362:
1363: /* Stay in the loop until we have received a complete packet. */
1364: for (;;) {
1365: /* Try to read a packet from the buffer. */
1.201 markus 1366: r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1367: if (r != 0)
1368: break;
1.62 markus 1369: if (!compat20 && (
1.201 markus 1370: *typep == SSH_SMSG_SUCCESS
1371: || *typep == SSH_SMSG_FAILURE
1372: || *typep == SSH_CMSG_EOF
1373: || *typep == SSH_CMSG_EXIT_CONFIRMATION))
1374: if ((r = sshpkt_get_end(ssh)) != 0)
1375: break;
1.14 markus 1376: /* If we got a packet, return it. */
1.201 markus 1377: if (*typep != SSH_MSG_NONE)
1378: break;
1.16 markus 1379: /*
1380: * Otherwise, wait for some data to arrive, add it to the
1381: * buffer, and try again.
1382: */
1.201 markus 1383: memset(setp, 0, howmany(state->connection_in + 1,
1.161 andreas 1384: NFDBITS) * sizeof(fd_mask));
1.201 markus 1385: FD_SET(state->connection_in, setp);
1.16 markus 1386:
1.201 markus 1387: if (state->packet_timeout_ms > 0) {
1388: ms_remain = state->packet_timeout_ms;
1.154 dtucker 1389: timeoutp = &timeout;
1390: }
1.14 markus 1391: /* Wait for some data to arrive. */
1.154 dtucker 1392: for (;;) {
1.201 markus 1393: if (state->packet_timeout_ms != -1) {
1.154 dtucker 1394: ms_to_timeval(&timeout, ms_remain);
1395: gettimeofday(&start, NULL);
1396: }
1.201 markus 1397: if ((r = select(state->connection_in + 1, setp,
1.161 andreas 1398: NULL, NULL, timeoutp)) >= 0)
1.154 dtucker 1399: break;
1.161 andreas 1400: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 1401: break;
1.201 markus 1402: if (state->packet_timeout_ms == -1)
1.154 dtucker 1403: continue;
1404: ms_subtract_diff(&start, &ms_remain);
1405: if (ms_remain <= 0) {
1.201 markus 1406: r = 0;
1.154 dtucker 1407: break;
1408: }
1409: }
1.204 djm 1410: if (r == 0)
1411: return SSH_ERR_CONN_TIMEOUT;
1.14 markus 1412: /* Read data from the socket. */
1.222 markus 1413: len = read(state->connection_in, buf, sizeof(buf));
1.210 markus 1414: if (len == 0) {
1415: r = SSH_ERR_CONN_CLOSED;
1416: goto out;
1417: }
1418: if (len < 0) {
1419: r = SSH_ERR_SYSTEM_ERROR;
1420: goto out;
1421: }
1.204 djm 1422:
1.14 markus 1423: /* Append it to the buffer. */
1.204 djm 1424: if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1.210 markus 1425: goto out;
1.14 markus 1426: }
1.210 markus 1427: out:
1.201 markus 1428: free(setp);
1429: return r;
1.1 deraadt 1430: }
1431:
1.77 djm 1432: int
1.201 markus 1433: ssh_packet_read(struct ssh *ssh)
1.77 djm 1434: {
1.201 markus 1435: u_char type;
1436: int r;
1437:
1438: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1439: fatal("%s: %s", __func__, ssh_err(r));
1440: return type;
1.77 djm 1441: }
1442:
1.16 markus 1443: /*
1444: * Waits until a packet has been received, verifies that its type matches
1445: * that given, and gives a fatal error and exits if there is a mismatch.
1446: */
1.1 deraadt 1447:
1.205 djm 1448: int
1449: ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1.1 deraadt 1450: {
1.205 djm 1451: int r;
1452: u_char type;
1.1 deraadt 1453:
1.205 djm 1454: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1455: return r;
1456: if (type != expected_type) {
1457: if ((r = sshpkt_disconnect(ssh,
1.201 markus 1458: "Protocol error: expected packet type %d, got %d",
1.205 djm 1459: expected_type, type)) != 0)
1460: return r;
1461: return SSH_ERR_PROTOCOL_ERROR;
1462: }
1463: return 0;
1.1 deraadt 1464: }
1465:
1466: /* Checks if a full packet is available in the data received so far via
1.14 markus 1467: * packet_process_incoming. If so, reads the packet; otherwise returns
1468: * SSH_MSG_NONE. This does not wait for data from the connection.
1469: *
1.150 dtucker 1470: * SSH_MSG_DISCONNECT is handled specially here. Also,
1471: * SSH_MSG_IGNORE messages are skipped by this function and are never returned
1472: * to higher levels.
1.14 markus 1473: */
1.1 deraadt 1474:
1.201 markus 1475: int
1476: ssh_packet_read_poll1(struct ssh *ssh, u_char *typep)
1.1 deraadt 1477: {
1.201 markus 1478: struct session_state *state = ssh->state;
1.40 markus 1479: u_int len, padded_len;
1.205 djm 1480: const char *emsg;
1.201 markus 1481: const u_char *cp;
1482: u_char *p;
1.40 markus 1483: u_int checksum, stored_checksum;
1.201 markus 1484: int r;
1485:
1486: *typep = SSH_MSG_NONE;
1.14 markus 1487:
1488: /* Check if input size is less than minimum packet size. */
1.201 markus 1489: if (sshbuf_len(state->input) < 4 + 8)
1490: return 0;
1.14 markus 1491: /* Get length of incoming packet. */
1.201 markus 1492: len = PEEK_U32(sshbuf_ptr(state->input));
1.205 djm 1493: if (len < 1 + 2 + 2 || len > 256 * 1024) {
1494: if ((r = sshpkt_disconnect(ssh, "Bad packet length %u",
1495: len)) != 0)
1496: return r;
1497: return SSH_ERR_CONN_CORRUPT;
1498: }
1.14 markus 1499: padded_len = (len + 8) & ~7;
1500:
1501: /* Check if the packet has been entirely received. */
1.201 markus 1502: if (sshbuf_len(state->input) < 4 + padded_len)
1503: return 0;
1.14 markus 1504:
1505: /* The entire packet is in buffer. */
1506:
1507: /* Consume packet length. */
1.201 markus 1508: if ((r = sshbuf_consume(state->input, 4)) != 0)
1509: goto out;
1.14 markus 1510:
1.62 markus 1511: /*
1512: * Cryptographic attack detector for ssh
1513: * (C)1998 CORE-SDI, Buenos Aires Argentina
1514: * Ariel Futoransky(futo@core-sdi.com)
1515: */
1.235 djm 1516: if (!cipher_ctx_is_plaintext(state->receive_context)) {
1.205 djm 1517: emsg = NULL;
1.201 markus 1518: switch (detect_attack(&state->deattack,
1519: sshbuf_ptr(state->input), padded_len)) {
1520: case DEATTACK_OK:
1521: break;
1.144 djm 1522: case DEATTACK_DETECTED:
1.205 djm 1523: emsg = "crc32 compensation attack detected";
1524: break;
1.144 djm 1525: case DEATTACK_DOS_DETECTED:
1.205 djm 1526: emsg = "deattack denial of service detected";
1527: break;
1.201 markus 1528: default:
1.205 djm 1529: emsg = "deattack error";
1530: break;
1531: }
1532: if (emsg != NULL) {
1533: error("%s", emsg);
1534: if ((r = sshpkt_disconnect(ssh, "%s", emsg)) != 0 ||
1535: (r = ssh_packet_write_wait(ssh)) != 0)
1536: return r;
1537: return SSH_ERR_CONN_CORRUPT;
1.144 djm 1538: }
1539: }
1.62 markus 1540:
1541: /* Decrypt data to incoming_packet. */
1.201 markus 1542: sshbuf_reset(state->incoming_packet);
1543: if ((r = sshbuf_reserve(state->incoming_packet, padded_len, &p)) != 0)
1544: goto out;
1.235 djm 1545: if ((r = cipher_crypt(state->receive_context, 0, p,
1.201 markus 1546: sshbuf_ptr(state->input), padded_len, 0, 0)) != 0)
1547: goto out;
1.62 markus 1548:
1.201 markus 1549: if ((r = sshbuf_consume(state->input, padded_len)) != 0)
1550: goto out;
1.1 deraadt 1551:
1552: #ifdef PACKET_DEBUG
1.14 markus 1553: fprintf(stderr, "read_poll plain: ");
1.201 markus 1554: sshbuf_dump(state->incoming_packet, stderr);
1.1 deraadt 1555: #endif
1556:
1.14 markus 1557: /* Compute packet checksum. */
1.201 markus 1558: checksum = ssh_crc32(sshbuf_ptr(state->incoming_packet),
1559: sshbuf_len(state->incoming_packet) - 4);
1.14 markus 1560:
1561: /* Skip padding. */
1.201 markus 1562: if ((r = sshbuf_consume(state->incoming_packet, 8 - len % 8)) != 0)
1563: goto out;
1.14 markus 1564:
1565: /* Test check bytes. */
1.205 djm 1566: if (len != sshbuf_len(state->incoming_packet)) {
1567: error("%s: len %d != sshbuf_len %zd", __func__,
1.201 markus 1568: len, sshbuf_len(state->incoming_packet));
1.205 djm 1569: if ((r = sshpkt_disconnect(ssh, "invalid packet length")) != 0 ||
1570: (r = ssh_packet_write_wait(ssh)) != 0)
1571: return r;
1572: return SSH_ERR_CONN_CORRUPT;
1573: }
1.14 markus 1574:
1.201 markus 1575: cp = sshbuf_ptr(state->incoming_packet) + len - 4;
1576: stored_checksum = PEEK_U32(cp);
1.205 djm 1577: if (checksum != stored_checksum) {
1578: error("Corrupted check bytes on input");
1579: if ((r = sshpkt_disconnect(ssh, "connection corrupted")) != 0 ||
1580: (r = ssh_packet_write_wait(ssh)) != 0)
1581: return r;
1582: return SSH_ERR_CONN_CORRUPT;
1583: }
1.201 markus 1584: if ((r = sshbuf_consume_end(state->incoming_packet, 4)) < 0)
1585: goto out;
1586:
1587: if (state->packet_compression) {
1588: sshbuf_reset(state->compression_buffer);
1589: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1590: state->compression_buffer)) != 0)
1591: goto out;
1592: sshbuf_reset(state->incoming_packet);
1593: if ((r = sshbuf_putb(state->incoming_packet,
1594: state->compression_buffer)) != 0)
1595: goto out;
1596: }
1597: state->p_read.packets++;
1598: state->p_read.bytes += padded_len + 4;
1599: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1600: goto out;
1.205 djm 1601: if (*typep < SSH_MSG_MIN || *typep > SSH_MSG_MAX) {
1602: error("Invalid ssh1 packet type: %d", *typep);
1603: if ((r = sshpkt_disconnect(ssh, "invalid packet type")) != 0 ||
1604: (r = ssh_packet_write_wait(ssh)) != 0)
1605: return r;
1606: return SSH_ERR_PROTOCOL_ERROR;
1607: }
1.201 markus 1608: r = 0;
1609: out:
1610: return r;
1.1 deraadt 1611: }
1.14 markus 1612:
1.201 markus 1613: int
1614: ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1615: {
1.201 markus 1616: struct session_state *state = ssh->state;
1.40 markus 1617: u_int padlen, need;
1.231 djm 1618: u_char *cp;
1.201 markus 1619: u_int maclen, aadlen = 0, authlen = 0, block_size;
1620: struct sshenc *enc = NULL;
1621: struct sshmac *mac = NULL;
1622: struct sshcomp *comp = NULL;
1.200 markus 1623: int r;
1.201 markus 1624:
1625: *typep = SSH_MSG_NONE;
1626:
1627: if (state->packet_discard)
1628: return 0;
1629:
1630: if (state->newkeys[MODE_IN] != NULL) {
1631: enc = &state->newkeys[MODE_IN]->enc;
1632: mac = &state->newkeys[MODE_IN]->mac;
1633: comp = &state->newkeys[MODE_IN]->comp;
1.180 markus 1634: /* disable mac for authenticated encryption */
1635: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1636: mac = NULL;
1.25 markus 1637: }
1638: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.88 markus 1639: block_size = enc ? enc->block_size : 8;
1.180 markus 1640: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1641:
1.201 markus 1642: if (aadlen && state->packlen == 0) {
1.235 djm 1643: if (cipher_get_length(state->receive_context,
1.201 markus 1644: &state->packlen, state->p_read.seqnr,
1645: sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1646: return 0;
1647: if (state->packlen < 1 + 4 ||
1648: state->packlen > PACKET_MAX_SIZE) {
1.178 markus 1649: #ifdef PACKET_DEBUG
1.201 markus 1650: sshbuf_dump(state->input, stderr);
1.178 markus 1651: #endif
1.201 markus 1652: logit("Bad packet length %u.", state->packlen);
1653: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1654: return r;
1.217 djm 1655: return SSH_ERR_CONN_CORRUPT;
1.178 markus 1656: }
1.201 markus 1657: sshbuf_reset(state->incoming_packet);
1658: } else if (state->packlen == 0) {
1.25 markus 1659: /*
1660: * check if input size is less than the cipher block size,
1661: * decrypt first block and extract length of incoming packet
1662: */
1.201 markus 1663: if (sshbuf_len(state->input) < block_size)
1664: return 0;
1665: sshbuf_reset(state->incoming_packet);
1666: if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1667: &cp)) != 0)
1668: goto out;
1.235 djm 1669: if ((r = cipher_crypt(state->receive_context,
1.201 markus 1670: state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1671: block_size, 0, 0)) != 0)
1672: goto out;
1673: state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1674: if (state->packlen < 1 + 4 ||
1675: state->packlen > PACKET_MAX_SIZE) {
1.110 markus 1676: #ifdef PACKET_DEBUG
1.201 markus 1677: fprintf(stderr, "input: \n");
1678: sshbuf_dump(state->input, stderr);
1679: fprintf(stderr, "incoming_packet: \n");
1680: sshbuf_dump(state->incoming_packet, stderr);
1.110 markus 1681: #endif
1.201 markus 1682: logit("Bad packet length %u.", state->packlen);
1.234 markus 1683: return ssh_packet_start_discard(ssh, enc, mac, 0,
1684: PACKET_MAX_SIZE);
1.25 markus 1685: }
1.201 markus 1686: if ((r = sshbuf_consume(state->input, block_size)) != 0)
1687: goto out;
1.25 markus 1688: }
1.201 markus 1689: DBG(debug("input: packet len %u", state->packlen+4));
1690:
1.178 markus 1691: if (aadlen) {
1692: /* only the payload is encrypted */
1.201 markus 1693: need = state->packlen;
1.178 markus 1694: } else {
1695: /*
1696: * the payload size and the payload are encrypted, but we
1697: * have a partial packet of block_size bytes
1698: */
1.201 markus 1699: need = 4 + state->packlen - block_size;
1.178 markus 1700: }
1.180 markus 1701: DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1702: " aadlen %d", block_size, need, maclen, authlen, aadlen));
1.158 markus 1703: if (need % block_size != 0) {
1704: logit("padding error: need %d block %d mod %d",
1.25 markus 1705: need, block_size, need % block_size);
1.234 markus 1706: return ssh_packet_start_discard(ssh, enc, mac, 0,
1707: PACKET_MAX_SIZE - block_size);
1.158 markus 1708: }
1.25 markus 1709: /*
1710: * check if the entire packet has been received and
1.178 markus 1711: * decrypt into incoming_packet:
1712: * 'aadlen' bytes are unencrypted, but authenticated.
1.180 markus 1713: * 'need' bytes are encrypted, followed by either
1714: * 'authlen' bytes of authentication tag or
1.178 markus 1715: * 'maclen' bytes of message authentication code.
1.25 markus 1716: */
1.201 markus 1717: if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1.231 djm 1718: return 0; /* packet is incomplete */
1.25 markus 1719: #ifdef PACKET_DEBUG
1720: fprintf(stderr, "read_poll enc/full: ");
1.201 markus 1721: sshbuf_dump(state->input, stderr);
1.25 markus 1722: #endif
1.231 djm 1723: /* EtM: check mac over encrypted input */
1.201 markus 1724: if (mac && mac->enabled && mac->etm) {
1.231 djm 1725: if ((r = mac_check(mac, state->p_read.seqnr,
1.201 markus 1726: sshbuf_ptr(state->input), aadlen + need,
1.231 djm 1727: sshbuf_ptr(state->input) + aadlen + need + authlen,
1728: maclen)) != 0) {
1729: if (r == SSH_ERR_MAC_INVALID)
1730: logit("Corrupted MAC on input.");
1.201 markus 1731: goto out;
1.231 djm 1732: }
1.201 markus 1733: }
1734: if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1735: &cp)) != 0)
1736: goto out;
1.235 djm 1737: if ((r = cipher_crypt(state->receive_context, state->p_read.seqnr, cp,
1.201 markus 1738: sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1739: goto out;
1740: if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1741: goto out;
1.29 markus 1742: if (mac && mac->enabled) {
1.231 djm 1743: /* Not EtM: check MAC over cleartext */
1744: if (!mac->etm && (r = mac_check(mac, state->p_read.seqnr,
1745: sshbuf_ptr(state->incoming_packet),
1746: sshbuf_len(state->incoming_packet),
1747: sshbuf_ptr(state->input), maclen)) != 0) {
1748: if (r != SSH_ERR_MAC_INVALID)
1.201 markus 1749: goto out;
1.159 markus 1750: logit("Corrupted MAC on input.");
1751: if (need > PACKET_MAX_SIZE)
1.201 markus 1752: return SSH_ERR_INTERNAL_ERROR;
1753: return ssh_packet_start_discard(ssh, enc, mac,
1.234 markus 1754: sshbuf_len(state->incoming_packet),
1755: PACKET_MAX_SIZE - need);
1.201 markus 1756: }
1.231 djm 1757: /* Remove MAC from input buffer */
1.201 markus 1758: DBG(debug("MAC #%d ok", state->p_read.seqnr));
1759: if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1760: goto out;
1.25 markus 1761: }
1.77 djm 1762: if (seqnr_p != NULL)
1.201 markus 1763: *seqnr_p = state->p_read.seqnr;
1764: if (++state->p_read.seqnr == 0)
1.106 itojun 1765: logit("incoming seqnr wraps around");
1.201 markus 1766: if (++state->p_read.packets == 0)
1767: if (!(ssh->compat & SSH_BUG_NOREKEY))
1768: return SSH_ERR_NEED_REKEY;
1769: state->p_read.blocks += (state->packlen + 4) / block_size;
1770: state->p_read.bytes += state->packlen + 4;
1.25 markus 1771:
1772: /* get padlen */
1.201 markus 1773: padlen = sshbuf_ptr(state->incoming_packet)[4];
1.25 markus 1774: DBG(debug("input: padlen %d", padlen));
1.205 djm 1775: if (padlen < 4) {
1776: if ((r = sshpkt_disconnect(ssh,
1777: "Corrupted padlen %d on input.", padlen)) != 0 ||
1778: (r = ssh_packet_write_wait(ssh)) != 0)
1779: return r;
1780: return SSH_ERR_CONN_CORRUPT;
1781: }
1.25 markus 1782:
1783: /* skip packet size + padlen, discard padding */
1.201 markus 1784: if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1785: ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1786: goto out;
1.25 markus 1787:
1.201 markus 1788: DBG(debug("input: len before de-compress %zd",
1789: sshbuf_len(state->incoming_packet)));
1.25 markus 1790: if (comp && comp->enabled) {
1.201 markus 1791: sshbuf_reset(state->compression_buffer);
1792: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1793: state->compression_buffer)) != 0)
1794: goto out;
1795: sshbuf_reset(state->incoming_packet);
1796: if ((r = sshbuf_putb(state->incoming_packet,
1797: state->compression_buffer)) != 0)
1798: goto out;
1799: DBG(debug("input: len after de-compress %zd",
1800: sshbuf_len(state->incoming_packet)));
1.25 markus 1801: }
1802: /*
1803: * get packet type, implies consume.
1804: * return length of payload (without type field)
1805: */
1.201 markus 1806: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1807: goto out;
1.226 djm 1808: if (ssh_packet_log_type(*typep))
1809: debug3("receive packet: type %u", *typep);
1.205 djm 1810: if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1811: if ((r = sshpkt_disconnect(ssh,
1812: "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1813: (r = ssh_packet_write_wait(ssh)) != 0)
1814: return r;
1815: return SSH_ERR_PROTOCOL_ERROR;
1816: }
1.238 markus 1817: if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1.201 markus 1818: r = ssh_packet_enable_delayed_compress(ssh);
1819: else
1820: r = 0;
1.25 markus 1821: #ifdef PACKET_DEBUG
1.201 markus 1822: fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1823: sshbuf_dump(state->incoming_packet, stderr);
1.25 markus 1824: #endif
1.62 markus 1825: /* reset for next packet */
1.201 markus 1826: state->packlen = 0;
1.228 djm 1827:
1828: /* do we need to rekey? */
1829: if (ssh_packet_need_rekeying(ssh, 0)) {
1830: debug3("%s: rekex triggered", __func__);
1831: if ((r = kex_start_rekex(ssh)) != 0)
1832: return r;
1833: }
1.201 markus 1834: out:
1835: return r;
1.25 markus 1836: }
1837:
1838: int
1.201 markus 1839: ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1840: {
1.201 markus 1841: struct session_state *state = ssh->state;
1.96 deraadt 1842: u_int reason, seqnr;
1.201 markus 1843: int r;
1844: u_char *msg;
1.62 markus 1845:
1.25 markus 1846: for (;;) {
1.201 markus 1847: msg = NULL;
1.62 markus 1848: if (compat20) {
1.201 markus 1849: r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1850: if (r != 0)
1851: return r;
1852: if (*typep) {
1853: state->keep_alive_timeouts = 0;
1854: DBG(debug("received packet type %d", *typep));
1.153 djm 1855: }
1.201 markus 1856: switch (*typep) {
1.150 dtucker 1857: case SSH2_MSG_IGNORE:
1.151 dtucker 1858: debug3("Received SSH2_MSG_IGNORE");
1.150 dtucker 1859: break;
1.25 markus 1860: case SSH2_MSG_DEBUG:
1.201 markus 1861: if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1862: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1863: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1.219 mmcc 1864: free(msg);
1.201 markus 1865: return r;
1866: }
1.25 markus 1867: debug("Remote: %.900s", msg);
1.186 djm 1868: free(msg);
1.25 markus 1869: break;
1870: case SSH2_MSG_DISCONNECT:
1.201 markus 1871: if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1872: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1873: return r;
1.182 djm 1874: /* Ignore normal client exit notifications */
1.201 markus 1875: do_log2(ssh->state->server_side &&
1.182 djm 1876: reason == SSH2_DISCONNECT_BY_APPLICATION ?
1877: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1.220 djm 1878: "Received disconnect from %s port %d:"
1879: "%u: %.400s", ssh_remote_ipaddr(ssh),
1880: ssh_remote_port(ssh), reason, msg);
1.186 djm 1881: free(msg);
1.201 markus 1882: return SSH_ERR_DISCONNECTED;
1.84 markus 1883: case SSH2_MSG_UNIMPLEMENTED:
1.201 markus 1884: if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1885: return r;
1.96 deraadt 1886: debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1887: seqnr);
1.150 dtucker 1888: break;
1.25 markus 1889: default:
1.201 markus 1890: return 0;
1.48 stevesk 1891: }
1.25 markus 1892: } else {
1.201 markus 1893: r = ssh_packet_read_poll1(ssh, typep);
1894: switch (*typep) {
1.188 djm 1895: case SSH_MSG_NONE:
1896: return SSH_MSG_NONE;
1.25 markus 1897: case SSH_MSG_IGNORE:
1898: break;
1899: case SSH_MSG_DEBUG:
1.201 markus 1900: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1901: return r;
1.25 markus 1902: debug("Remote: %.900s", msg);
1.186 djm 1903: free(msg);
1.25 markus 1904: break;
1905: case SSH_MSG_DISCONNECT:
1.201 markus 1906: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1907: return r;
1.220 djm 1908: error("Received disconnect from %s port %d: "
1909: "%.400s", ssh_remote_ipaddr(ssh),
1910: ssh_remote_port(ssh), msg);
1.201 markus 1911: free(msg);
1912: return SSH_ERR_DISCONNECTED;
1.25 markus 1913: default:
1.201 markus 1914: DBG(debug("received packet type %d", *typep));
1915: return 0;
1.48 stevesk 1916: }
1.25 markus 1917: }
1918: }
1919: }
1920:
1.16 markus 1921: /*
1922: * Buffers the given amount of input characters. This is intended to be used
1923: * together with packet_read_poll.
1924: */
1.1 deraadt 1925:
1.204 djm 1926: int
1.201 markus 1927: ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1.1 deraadt 1928: {
1.201 markus 1929: struct session_state *state = ssh->state;
1930: int r;
1931:
1932: if (state->packet_discard) {
1933: state->keep_alive_timeouts = 0; /* ?? */
1934: if (len >= state->packet_discard) {
1935: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1.204 djm 1936: return r;
1.201 markus 1937: }
1938: state->packet_discard -= len;
1.204 djm 1939: return 0;
1.159 markus 1940: }
1.201 markus 1941: if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1.204 djm 1942: return r;
1943:
1944: return 0;
1.28 markus 1945: }
1946:
1947: int
1.201 markus 1948: ssh_packet_remaining(struct ssh *ssh)
1.28 markus 1949: {
1.201 markus 1950: return sshbuf_len(ssh->state->incoming_packet);
1.1 deraadt 1951: }
1952:
1.16 markus 1953: /*
1954: * Sends a diagnostic message from the server to the client. This message
1955: * can be sent at any time (but not while constructing another message). The
1956: * message is printed immediately, but only if the client is being executed
1957: * in verbose mode. These messages are primarily intended to ease debugging
1958: * authentication problems. The length of the formatted message must not
1.205 djm 1959: * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1.16 markus 1960: */
1.2 provos 1961: void
1.201 markus 1962: ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1963: {
1.14 markus 1964: char buf[1024];
1965: va_list args;
1.201 markus 1966: int r;
1.39 markus 1967:
1.201 markus 1968: if (compat20 && (ssh->compat & SSH_BUG_DEBUG))
1.39 markus 1969: return;
1.14 markus 1970:
1971: va_start(args, fmt);
1972: vsnprintf(buf, sizeof(buf), fmt, args);
1973: va_end(args);
1974:
1.30 markus 1975: if (compat20) {
1.201 markus 1976: if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1977: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1978: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1979: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1980: (r = sshpkt_send(ssh)) != 0)
1981: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1982: } else {
1.201 markus 1983: if ((r = sshpkt_start(ssh, SSH_MSG_DEBUG)) != 0 ||
1984: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1985: (r = sshpkt_send(ssh)) != 0)
1986: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1987: }
1.205 djm 1988: if ((r = ssh_packet_write_wait(ssh)) != 0)
1989: fatal("%s: %s", __func__, ssh_err(r));
1990: }
1991:
1992: /*
1993: * Pretty-print connection-terminating errors and exit.
1994: */
1995: void
1996: sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1997: {
1998: switch (r) {
1999: case SSH_ERR_CONN_CLOSED:
1.232 dtucker 2000: logdie("Connection closed by %.200s port %d",
1.220 djm 2001: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.205 djm 2002: case SSH_ERR_CONN_TIMEOUT:
1.232 dtucker 2003: logdie("Connection %s %.200s port %d timed out",
1.220 djm 2004: ssh->state->server_side ? "from" : "to",
2005: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 2006: case SSH_ERR_DISCONNECTED:
1.232 dtucker 2007: logdie("Disconnected from %.200s port %d",
1.220 djm 2008: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 2009: case SSH_ERR_SYSTEM_ERROR:
1.232 dtucker 2010: if (errno == ECONNRESET)
2011: logdie("Connection reset by %.200s port %d",
1.220 djm 2012: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.213 djm 2013: /* FALLTHROUGH */
2014: case SSH_ERR_NO_CIPHER_ALG_MATCH:
2015: case SSH_ERR_NO_MAC_ALG_MATCH:
2016: case SSH_ERR_NO_COMPRESS_ALG_MATCH:
2017: case SSH_ERR_NO_KEX_ALG_MATCH:
2018: case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
2019: if (ssh && ssh->kex && ssh->kex->failed_choice) {
1.232 dtucker 2020: logdie("Unable to negotiate with %.200s port %d: %s. "
1.213 djm 2021: "Their offer: %s", ssh_remote_ipaddr(ssh),
1.220 djm 2022: ssh_remote_port(ssh), ssh_err(r),
2023: ssh->kex->failed_choice);
1.212 djm 2024: }
2025: /* FALLTHROUGH */
1.205 djm 2026: default:
1.232 dtucker 2027: logdie("%s%sConnection %s %.200s port %d: %s",
1.205 djm 2028: tag != NULL ? tag : "", tag != NULL ? ": " : "",
1.220 djm 2029: ssh->state->server_side ? "from" : "to",
2030: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), ssh_err(r));
1.205 djm 2031: }
1.1 deraadt 2032: }
2033:
1.16 markus 2034: /*
2035: * Logs the error plus constructs and sends a disconnect packet, closes the
2036: * connection, and exits. This function never returns. The error message
2037: * should not contain a newline. The length of the formatted message must
2038: * not exceed 1024 bytes.
2039: */
1.2 provos 2040: void
1.201 markus 2041: ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 2042: {
1.14 markus 2043: char buf[1024];
2044: va_list args;
2045: static int disconnecting = 0;
1.201 markus 2046: int r;
1.97 deraadt 2047:
1.14 markus 2048: if (disconnecting) /* Guard against recursive invocations. */
2049: fatal("packet_disconnect called recursively.");
2050: disconnecting = 1;
2051:
1.16 markus 2052: /*
2053: * Format the message. Note that the caller must make sure the
2054: * message is of limited size.
2055: */
1.14 markus 2056: va_start(args, fmt);
2057: vsnprintf(buf, sizeof(buf), fmt, args);
2058: va_end(args);
2059:
1.99 markus 2060: /* Display the error locally */
1.106 itojun 2061: logit("Disconnecting: %.100s", buf);
1.99 markus 2062:
1.205 djm 2063: /*
2064: * Send the disconnect message to the other side, and wait
2065: * for it to get sent.
2066: */
2067: if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
2068: sshpkt_fatal(ssh, __func__, r);
2069:
2070: if ((r = ssh_packet_write_wait(ssh)) != 0)
2071: sshpkt_fatal(ssh, __func__, r);
1.14 markus 2072:
2073: /* Close the connection. */
1.201 markus 2074: ssh_packet_close(ssh);
1.112 markus 2075: cleanup_exit(255);
1.1 deraadt 2076: }
2077:
1.205 djm 2078: /*
2079: * Checks if there is any buffered output, and tries to write some of
2080: * the output.
2081: */
2082: int
1.201 markus 2083: ssh_packet_write_poll(struct ssh *ssh)
1.1 deraadt 2084: {
1.201 markus 2085: struct session_state *state = ssh->state;
2086: int len = sshbuf_len(state->output);
1.222 markus 2087: int r;
1.97 deraadt 2088:
1.14 markus 2089: if (len > 0) {
1.222 markus 2090: len = write(state->connection_out,
2091: sshbuf_ptr(state->output), len);
1.156 djm 2092: if (len == -1) {
2093: if (errno == EINTR || errno == EAGAIN)
1.205 djm 2094: return 0;
2095: return SSH_ERR_SYSTEM_ERROR;
1.14 markus 2096: }
1.222 markus 2097: if (len == 0)
1.205 djm 2098: return SSH_ERR_CONN_CLOSED;
1.201 markus 2099: if ((r = sshbuf_consume(state->output, len)) != 0)
1.205 djm 2100: return r;
1.14 markus 2101: }
1.205 djm 2102: return 0;
1.1 deraadt 2103: }
2104:
1.16 markus 2105: /*
2106: * Calls packet_write_poll repeatedly until all pending output data has been
2107: * written.
2108: */
1.205 djm 2109: int
1.201 markus 2110: ssh_packet_write_wait(struct ssh *ssh)
1.1 deraadt 2111: {
1.56 millert 2112: fd_set *setp;
1.205 djm 2113: int ret, r, ms_remain = 0;
1.154 dtucker 2114: struct timeval start, timeout, *timeoutp = NULL;
1.201 markus 2115: struct session_state *state = ssh->state;
1.56 millert 2116:
1.214 deraadt 2117: setp = calloc(howmany(state->connection_out + 1,
1.161 andreas 2118: NFDBITS), sizeof(fd_mask));
1.201 markus 2119: if (setp == NULL)
1.205 djm 2120: return SSH_ERR_ALLOC_FAIL;
1.216 gsoares 2121: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2122: free(setp);
1.215 djm 2123: return r;
1.216 gsoares 2124: }
1.201 markus 2125: while (ssh_packet_have_data_to_write(ssh)) {
2126: memset(setp, 0, howmany(state->connection_out + 1,
1.161 andreas 2127: NFDBITS) * sizeof(fd_mask));
1.201 markus 2128: FD_SET(state->connection_out, setp);
1.154 dtucker 2129:
1.201 markus 2130: if (state->packet_timeout_ms > 0) {
2131: ms_remain = state->packet_timeout_ms;
1.154 dtucker 2132: timeoutp = &timeout;
2133: }
2134: for (;;) {
1.201 markus 2135: if (state->packet_timeout_ms != -1) {
1.154 dtucker 2136: ms_to_timeval(&timeout, ms_remain);
2137: gettimeofday(&start, NULL);
2138: }
1.201 markus 2139: if ((ret = select(state->connection_out + 1,
1.161 andreas 2140: NULL, setp, NULL, timeoutp)) >= 0)
1.154 dtucker 2141: break;
1.161 andreas 2142: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 2143: break;
1.201 markus 2144: if (state->packet_timeout_ms == -1)
1.154 dtucker 2145: continue;
2146: ms_subtract_diff(&start, &ms_remain);
2147: if (ms_remain <= 0) {
2148: ret = 0;
2149: break;
2150: }
2151: }
2152: if (ret == 0) {
1.205 djm 2153: free(setp);
2154: return SSH_ERR_CONN_TIMEOUT;
2155: }
2156: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2157: free(setp);
2158: return r;
1.154 dtucker 2159: }
1.14 markus 2160: }
1.186 djm 2161: free(setp);
1.205 djm 2162: return 0;
1.1 deraadt 2163: }
2164:
2165: /* Returns true if there is buffered data to write to the connection. */
2166:
1.2 provos 2167: int
1.201 markus 2168: ssh_packet_have_data_to_write(struct ssh *ssh)
1.1 deraadt 2169: {
1.201 markus 2170: return sshbuf_len(ssh->state->output) != 0;
1.1 deraadt 2171: }
2172:
2173: /* Returns true if there is not too much data to write to the connection. */
2174:
1.2 provos 2175: int
1.201 markus 2176: ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1.1 deraadt 2177: {
1.201 markus 2178: if (ssh->state->interactive_mode)
2179: return sshbuf_len(ssh->state->output) < 16384;
1.14 markus 2180: else
1.201 markus 2181: return sshbuf_len(ssh->state->output) < 128 * 1024;
1.1 deraadt 2182: }
2183:
1.201 markus 2184: void
2185: ssh_packet_set_tos(struct ssh *ssh, int tos)
1.101 markus 2186: {
1.201 markus 2187: if (!ssh_packet_connection_is_on_socket(ssh))
1.101 markus 2188: return;
1.201 markus 2189: switch (ssh_packet_connection_af(ssh)) {
1.173 djm 2190: case AF_INET:
2191: debug3("%s: set IP_TOS 0x%02x", __func__, tos);
1.201 markus 2192: if (setsockopt(ssh->state->connection_in,
1.173 djm 2193: IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2194: error("setsockopt IP_TOS %d: %.100s:",
2195: tos, strerror(errno));
2196: break;
2197: case AF_INET6:
2198: debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
1.201 markus 2199: if (setsockopt(ssh->state->connection_in,
1.173 djm 2200: IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2201: error("setsockopt IPV6_TCLASS %d: %.100s:",
2202: tos, strerror(errno));
2203: break;
2204: }
1.101 markus 2205: }
2206:
1.1 deraadt 2207: /* Informs that the current session is interactive. Sets IP flags for that. */
2208:
1.2 provos 2209: void
1.201 markus 2210: ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
1.1 deraadt 2211: {
1.201 markus 2212: struct session_state *state = ssh->state;
2213:
2214: if (state->set_interactive_called)
1.43 markus 2215: return;
1.201 markus 2216: state->set_interactive_called = 1;
1.1 deraadt 2217:
1.14 markus 2218: /* Record that we are in interactive mode. */
1.201 markus 2219: state->interactive_mode = interactive;
1.1 deraadt 2220:
1.19 markus 2221: /* Only set socket options if using a socket. */
1.201 markus 2222: if (!ssh_packet_connection_is_on_socket(ssh))
1.14 markus 2223: return;
1.201 markus 2224: set_nodelay(state->connection_in);
2225: ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2226: qos_bulk);
1.1 deraadt 2227: }
2228:
2229: /* Returns true if the current connection is interactive. */
2230:
1.2 provos 2231: int
1.201 markus 2232: ssh_packet_is_interactive(struct ssh *ssh)
1.1 deraadt 2233: {
1.201 markus 2234: return ssh->state->interactive_mode;
1.12 markus 2235: }
2236:
1.113 deraadt 2237: int
1.201 markus 2238: ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
1.12 markus 2239: {
1.201 markus 2240: struct session_state *state = ssh->state;
2241:
2242: if (state->set_maxsize_called) {
1.106 itojun 2243: logit("packet_set_maxsize: called twice: old %d new %d",
1.201 markus 2244: state->max_packet_size, s);
1.14 markus 2245: return -1;
2246: }
2247: if (s < 4 * 1024 || s > 1024 * 1024) {
1.106 itojun 2248: logit("packet_set_maxsize: bad size %d", s);
1.14 markus 2249: return -1;
2250: }
1.201 markus 2251: state->set_maxsize_called = 1;
1.66 markus 2252: debug("packet_set_maxsize: setting to %d", s);
1.201 markus 2253: state->max_packet_size = s;
1.14 markus 2254: return s;
1.53 markus 2255: }
2256:
1.161 andreas 2257: int
1.201 markus 2258: ssh_packet_inc_alive_timeouts(struct ssh *ssh)
1.161 andreas 2259: {
1.201 markus 2260: return ++ssh->state->keep_alive_timeouts;
1.161 andreas 2261: }
2262:
2263: void
1.201 markus 2264: ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
1.161 andreas 2265: {
1.201 markus 2266: ssh->state->keep_alive_timeouts = ka;
1.161 andreas 2267: }
2268:
2269: u_int
1.201 markus 2270: ssh_packet_get_maxsize(struct ssh *ssh)
1.71 markus 2271: {
1.201 markus 2272: return ssh->state->max_packet_size;
1.71 markus 2273: }
2274:
1.53 markus 2275: /*
2276: * 9.2. Ignored Data Message
1.61 markus 2277: *
1.53 markus 2278: * byte SSH_MSG_IGNORE
2279: * string data
1.61 markus 2280: *
1.53 markus 2281: * All implementations MUST understand (and ignore) this message at any
2282: * time (after receiving the protocol version). No implementation is
2283: * required to send them. This message can be used as an additional
2284: * protection measure against advanced traffic analysis techniques.
2285: */
1.54 markus 2286: void
1.201 markus 2287: ssh_packet_send_ignore(struct ssh *ssh, int nbytes)
1.54 markus 2288: {
1.115 avsm 2289: u_int32_t rnd = 0;
1.201 markus 2290: int r, i;
1.54 markus 2291:
1.201 markus 2292: if ((r = sshpkt_start(ssh, compat20 ?
2293: SSH2_MSG_IGNORE : SSH_MSG_IGNORE)) != 0 ||
2294: (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2295: fatal("%s: %s", __func__, ssh_err(r));
1.75 deraadt 2296: for (i = 0; i < nbytes; i++) {
1.53 markus 2297: if (i % 4 == 0)
1.115 avsm 2298: rnd = arc4random();
1.201 markus 2299: if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2300: fatal("%s: %s", __func__, ssh_err(r));
1.115 avsm 2301: rnd >>= 8;
1.53 markus 2302: }
1.105 markus 2303: }
2304:
2305: void
1.224 dtucker 2306: ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, time_t seconds)
1.105 markus 2307: {
1.224 dtucker 2308: debug3("rekey after %llu bytes, %d seconds", (unsigned long long)bytes,
1.184 dtucker 2309: (int)seconds);
1.201 markus 2310: ssh->state->rekey_limit = bytes;
2311: ssh->state->rekey_interval = seconds;
1.184 dtucker 2312: }
2313:
2314: time_t
1.201 markus 2315: ssh_packet_get_rekey_timeout(struct ssh *ssh)
1.184 dtucker 2316: {
2317: time_t seconds;
2318:
1.201 markus 2319: seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
1.187 dtucker 2320: monotime();
1.185 dtucker 2321: return (seconds <= 0 ? 1 : seconds);
1.118 markus 2322: }
2323:
2324: void
1.201 markus 2325: ssh_packet_set_server(struct ssh *ssh)
1.118 markus 2326: {
1.201 markus 2327: ssh->state->server_side = 1;
1.118 markus 2328: }
2329:
2330: void
1.201 markus 2331: ssh_packet_set_authenticated(struct ssh *ssh)
1.118 markus 2332: {
1.201 markus 2333: ssh->state->after_authentication = 1;
1.161 andreas 2334: }
2335:
2336: void *
1.201 markus 2337: ssh_packet_get_input(struct ssh *ssh)
1.161 andreas 2338: {
1.201 markus 2339: return (void *)ssh->state->input;
1.161 andreas 2340: }
2341:
2342: void *
1.201 markus 2343: ssh_packet_get_output(struct ssh *ssh)
1.161 andreas 2344: {
1.201 markus 2345: return (void *)ssh->state->output;
1.166 andreas 2346: }
2347:
1.196 markus 2348: /* Reset after_authentication and reset compression in post-auth privsep */
1.201 markus 2349: static int
2350: ssh_packet_set_postauth(struct ssh *ssh)
1.196 markus 2351: {
1.239 djm 2352: int r;
1.196 markus 2353:
2354: debug("%s: called", __func__);
2355: /* This was set in net child, but is not visible in user child */
1.201 markus 2356: ssh->state->after_authentication = 1;
2357: ssh->state->rekeying = 0;
1.239 djm 2358: if ((r = ssh_packet_enable_delayed_compress(ssh)) != 0)
2359: return r;
1.201 markus 2360: return 0;
2361: }
2362:
2363: /* Packet state (de-)serialization for privsep */
2364:
2365: /* turn kex into a blob for packet state serialization */
2366: static int
2367: kex_to_blob(struct sshbuf *m, struct kex *kex)
2368: {
2369: int r;
2370:
2371: if ((r = sshbuf_put_string(m, kex->session_id,
2372: kex->session_id_len)) != 0 ||
2373: (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2374: (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2375: (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2376: (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2377: (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2378: (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2379: (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2380: (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2381: return r;
2382: return 0;
2383: }
2384:
2385: /* turn key exchange results into a blob for packet state serialization */
2386: static int
2387: newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2388: {
2389: struct sshbuf *b;
2390: struct sshcipher_ctx *cc;
2391: struct sshcomp *comp;
2392: struct sshenc *enc;
2393: struct sshmac *mac;
2394: struct newkeys *newkey;
2395: int r;
2396:
2397: if ((newkey = ssh->state->newkeys[mode]) == NULL)
2398: return SSH_ERR_INTERNAL_ERROR;
2399: enc = &newkey->enc;
2400: mac = &newkey->mac;
2401: comp = &newkey->comp;
1.235 djm 2402: cc = (mode == MODE_OUT) ? ssh->state->send_context :
2403: ssh->state->receive_context;
1.201 markus 2404: if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2405: return r;
2406: if ((b = sshbuf_new()) == NULL)
2407: return SSH_ERR_ALLOC_FAIL;
2408: /* The cipher struct is constant and shared, you export pointer */
2409: if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2410: (r = sshbuf_put(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2411: (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2412: (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2413: (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2414: (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2415: goto out;
2416: if (cipher_authlen(enc->cipher) == 0) {
2417: if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2418: (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2419: (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2420: goto out;
2421: }
2422: if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2423: (r = sshbuf_put_cstring(b, comp->name)) != 0)
2424: goto out;
2425: r = sshbuf_put_stringb(m, b);
2426: out:
1.221 mmcc 2427: sshbuf_free(b);
1.201 markus 2428: return r;
2429: }
2430:
2431: /* serialize packet state into a blob */
2432: int
2433: ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2434: {
2435: struct session_state *state = ssh->state;
2436: u_char *p;
2437: size_t slen, rlen;
2438: int r, ssh1cipher;
2439:
2440: if (!compat20) {
1.235 djm 2441: ssh1cipher = cipher_ctx_get_number(state->receive_context);
2442: slen = cipher_get_keyiv_len(state->send_context);
2443: rlen = cipher_get_keyiv_len(state->receive_context);
1.201 markus 2444: if ((r = sshbuf_put_u32(m, state->remote_protocol_flags)) != 0 ||
2445: (r = sshbuf_put_u32(m, ssh1cipher)) != 0 ||
2446: (r = sshbuf_put_string(m, state->ssh1_key, state->ssh1_keylen)) != 0 ||
2447: (r = sshbuf_put_u32(m, slen)) != 0 ||
2448: (r = sshbuf_reserve(m, slen, &p)) != 0 ||
1.235 djm 2449: (r = cipher_get_keyiv(state->send_context, p, slen)) != 0 ||
1.201 markus 2450: (r = sshbuf_put_u32(m, rlen)) != 0 ||
2451: (r = sshbuf_reserve(m, rlen, &p)) != 0 ||
1.235 djm 2452: (r = cipher_get_keyiv(state->receive_context, p, rlen)) != 0)
1.201 markus 2453: return r;
2454: } else {
2455: if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2456: (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2457: (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
1.224 dtucker 2458: (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
1.208 markus 2459: (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
1.201 markus 2460: (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2461: (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2462: (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2463: (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2464: (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2465: (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2466: (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2467: (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0)
2468: return r;
2469: }
2470:
1.235 djm 2471: slen = cipher_get_keycontext(state->send_context, NULL);
2472: rlen = cipher_get_keycontext(state->receive_context, NULL);
1.201 markus 2473: if ((r = sshbuf_put_u32(m, slen)) != 0 ||
2474: (r = sshbuf_reserve(m, slen, &p)) != 0)
2475: return r;
1.235 djm 2476: if (cipher_get_keycontext(state->send_context, p) != (int)slen)
1.201 markus 2477: return SSH_ERR_INTERNAL_ERROR;
2478: if ((r = sshbuf_put_u32(m, rlen)) != 0 ||
2479: (r = sshbuf_reserve(m, rlen, &p)) != 0)
2480: return r;
1.235 djm 2481: if (cipher_get_keycontext(state->receive_context, p) != (int)rlen)
1.201 markus 2482: return SSH_ERR_INTERNAL_ERROR;
1.239 djm 2483: if ((r = sshbuf_put_stringb(m, state->input)) != 0 ||
1.201 markus 2484: (r = sshbuf_put_stringb(m, state->output)) != 0)
2485: return r;
2486:
2487: return 0;
2488: }
2489:
2490: /* restore key exchange results from blob for packet state de-serialization */
2491: static int
2492: newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2493: {
2494: struct sshbuf *b = NULL;
2495: struct sshcomp *comp;
2496: struct sshenc *enc;
2497: struct sshmac *mac;
2498: struct newkeys *newkey = NULL;
2499: size_t keylen, ivlen, maclen;
2500: int r;
2501:
2502: if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2503: r = SSH_ERR_ALLOC_FAIL;
2504: goto out;
2505: }
2506: if ((r = sshbuf_froms(m, &b)) != 0)
2507: goto out;
2508: #ifdef DEBUG_PK
2509: sshbuf_dump(b, stderr);
2510: #endif
2511: enc = &newkey->enc;
2512: mac = &newkey->mac;
2513: comp = &newkey->comp;
2514:
2515: if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2516: (r = sshbuf_get(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2517: (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2518: (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2519: (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2520: (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2521: goto out;
2522: if (cipher_authlen(enc->cipher) == 0) {
2523: if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2524: goto out;
2525: if ((r = mac_setup(mac, mac->name)) != 0)
2526: goto out;
2527: if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2528: (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2529: goto out;
2530: if (maclen > mac->key_len) {
2531: r = SSH_ERR_INVALID_FORMAT;
2532: goto out;
2533: }
2534: mac->key_len = maclen;
2535: }
2536: if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2537: (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2538: goto out;
2539: if (enc->name == NULL ||
2540: cipher_by_name(enc->name) != enc->cipher) {
2541: r = SSH_ERR_INVALID_FORMAT;
2542: goto out;
2543: }
2544: if (sshbuf_len(b) != 0) {
2545: r = SSH_ERR_INVALID_FORMAT;
2546: goto out;
2547: }
2548: enc->key_len = keylen;
2549: enc->iv_len = ivlen;
2550: ssh->kex->newkeys[mode] = newkey;
2551: newkey = NULL;
2552: r = 0;
2553: out:
1.219 mmcc 2554: free(newkey);
1.221 mmcc 2555: sshbuf_free(b);
1.201 markus 2556: return r;
2557: }
2558:
2559: /* restore kex from blob for packet state de-serialization */
2560: static int
2561: kex_from_blob(struct sshbuf *m, struct kex **kexp)
2562: {
2563: struct kex *kex;
2564: int r;
2565:
2566: if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2567: (kex->my = sshbuf_new()) == NULL ||
2568: (kex->peer = sshbuf_new()) == NULL) {
2569: r = SSH_ERR_ALLOC_FAIL;
2570: goto out;
2571: }
2572: if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2573: (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2574: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2575: (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2576: (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2577: (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2578: (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2579: (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2580: (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2581: goto out;
2582: kex->server = 1;
2583: kex->done = 1;
2584: r = 0;
2585: out:
2586: if (r != 0 || kexp == NULL) {
2587: if (kex != NULL) {
1.221 mmcc 2588: sshbuf_free(kex->my);
2589: sshbuf_free(kex->peer);
1.201 markus 2590: free(kex);
2591: }
2592: if (kexp != NULL)
2593: *kexp = NULL;
2594: } else {
2595: *kexp = kex;
2596: }
2597: return r;
2598: }
2599:
2600: /*
2601: * Restore packet state from content of blob 'm' (de-serialization).
2602: * Note that 'm' will be partially consumed on parsing or any other errors.
2603: */
2604: int
2605: ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2606: {
2607: struct session_state *state = ssh->state;
2608: const u_char *ssh1key, *ivin, *ivout, *keyin, *keyout, *input, *output;
2609: size_t ssh1keylen, rlen, slen, ilen, olen;
2610: int r;
2611: u_int ssh1cipher = 0;
2612:
2613: if (!compat20) {
2614: if ((r = sshbuf_get_u32(m, &state->remote_protocol_flags)) != 0 ||
2615: (r = sshbuf_get_u32(m, &ssh1cipher)) != 0 ||
2616: (r = sshbuf_get_string_direct(m, &ssh1key, &ssh1keylen)) != 0 ||
2617: (r = sshbuf_get_string_direct(m, &ivout, &slen)) != 0 ||
2618: (r = sshbuf_get_string_direct(m, &ivin, &rlen)) != 0)
2619: return r;
2620: if (ssh1cipher > INT_MAX)
2621: return SSH_ERR_KEY_UNKNOWN_CIPHER;
2622: ssh_packet_set_encryption_key(ssh, ssh1key, ssh1keylen,
2623: (int)ssh1cipher);
1.235 djm 2624: if (cipher_get_keyiv_len(state->send_context) != (int)slen ||
2625: cipher_get_keyiv_len(state->receive_context) != (int)rlen)
1.201 markus 2626: return SSH_ERR_INVALID_FORMAT;
1.235 djm 2627: if ((r = cipher_set_keyiv(state->send_context, ivout)) != 0 ||
2628: (r = cipher_set_keyiv(state->receive_context, ivin)) != 0)
1.201 markus 2629: return r;
2630: } else {
2631: if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2632: (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2633: (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
1.224 dtucker 2634: (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
1.208 markus 2635: (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
1.201 markus 2636: (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2637: (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2638: (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2639: (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2640: (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2641: (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2642: (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2643: (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2644: return r;
1.208 markus 2645: /*
2646: * We set the time here so that in post-auth privsep slave we
2647: * count from the completion of the authentication.
2648: */
2649: state->rekey_time = monotime();
1.201 markus 2650: /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2651: if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2652: (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2653: return r;
2654: }
2655: if ((r = sshbuf_get_string_direct(m, &keyout, &slen)) != 0 ||
2656: (r = sshbuf_get_string_direct(m, &keyin, &rlen)) != 0)
2657: return r;
1.235 djm 2658: if (cipher_get_keycontext(state->send_context, NULL) != (int)slen ||
2659: cipher_get_keycontext(state->receive_context, NULL) != (int)rlen)
1.201 markus 2660: return SSH_ERR_INVALID_FORMAT;
1.235 djm 2661: cipher_set_keycontext(state->send_context, keyout);
2662: cipher_set_keycontext(state->receive_context, keyin);
1.201 markus 2663:
1.239 djm 2664: if ((r = ssh_packet_set_postauth(ssh)) != 0)
1.201 markus 2665: return r;
2666:
2667: sshbuf_reset(state->input);
2668: sshbuf_reset(state->output);
2669: if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2670: (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2671: (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2672: (r = sshbuf_put(state->output, output, olen)) != 0)
2673: return r;
2674:
2675: if (sshbuf_len(m))
2676: return SSH_ERR_INVALID_FORMAT;
2677: debug3("%s: done", __func__);
2678: return 0;
2679: }
2680:
2681: /* NEW API */
2682:
2683: /* put data to the outgoing packet */
2684:
2685: int
2686: sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2687: {
2688: return sshbuf_put(ssh->state->outgoing_packet, v, len);
2689: }
2690:
2691: int
2692: sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2693: {
2694: return sshbuf_putb(ssh->state->outgoing_packet, b);
2695: }
2696:
2697: int
2698: sshpkt_put_u8(struct ssh *ssh, u_char val)
2699: {
2700: return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2701: }
2702:
2703: int
2704: sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2705: {
2706: return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2707: }
2708:
2709: int
2710: sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2711: {
2712: return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2713: }
2714:
2715: int
2716: sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2717: {
2718: return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2719: }
2720:
2721: int
2722: sshpkt_put_cstring(struct ssh *ssh, const void *v)
2723: {
2724: return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2725: }
2726:
2727: int
2728: sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2729: {
2730: return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2731: }
2732:
1.211 djm 2733: #ifdef WITH_OPENSSL
1.201 markus 2734: int
2735: sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2736: {
2737: return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2738: }
2739:
1.211 djm 2740: #ifdef WITH_SSH1
1.201 markus 2741: int
2742: sshpkt_put_bignum1(struct ssh *ssh, const BIGNUM *v)
2743: {
2744: return sshbuf_put_bignum1(ssh->state->outgoing_packet, v);
2745: }
1.211 djm 2746: #endif /* WITH_SSH1 */
1.201 markus 2747:
2748: int
2749: sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2750: {
2751: return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2752: }
1.211 djm 2753: #endif /* WITH_OPENSSL */
1.201 markus 2754:
2755: /* fetch data from the incoming packet */
2756:
2757: int
2758: sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2759: {
2760: return sshbuf_get(ssh->state->incoming_packet, valp, len);
2761: }
2762:
2763: int
2764: sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2765: {
2766: return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2767: }
2768:
2769: int
2770: sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2771: {
2772: return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2773: }
2774:
2775: int
2776: sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2777: {
2778: return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2779: }
2780:
2781: int
2782: sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2783: {
2784: return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2785: }
2786:
2787: int
2788: sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2789: {
2790: return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2791: }
2792:
2793: int
2794: sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2795: {
2796: return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2797: }
2798:
1.211 djm 2799: #ifdef WITH_OPENSSL
1.201 markus 2800: int
2801: sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2802: {
2803: return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2804: }
2805:
1.211 djm 2806: #ifdef WITH_SSH1
1.201 markus 2807: int
2808: sshpkt_get_bignum1(struct ssh *ssh, BIGNUM *v)
2809: {
2810: return sshbuf_get_bignum1(ssh->state->incoming_packet, v);
2811: }
1.211 djm 2812: #endif /* WITH_SSH1 */
1.201 markus 2813:
2814: int
2815: sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2816: {
2817: return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2818: }
1.211 djm 2819: #endif /* WITH_OPENSSL */
1.201 markus 2820:
2821: int
2822: sshpkt_get_end(struct ssh *ssh)
2823: {
2824: if (sshbuf_len(ssh->state->incoming_packet) > 0)
2825: return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2826: return 0;
2827: }
2828:
2829: const u_char *
2830: sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2831: {
2832: if (lenp != NULL)
2833: *lenp = sshbuf_len(ssh->state->incoming_packet);
2834: return sshbuf_ptr(ssh->state->incoming_packet);
2835: }
2836:
2837: /* start a new packet */
2838:
2839: int
2840: sshpkt_start(struct ssh *ssh, u_char type)
2841: {
2842: u_char buf[9];
2843: int len;
2844:
2845: DBG(debug("packet_start[%d]", type));
2846: len = compat20 ? 6 : 9;
2847: memset(buf, 0, len - 1);
2848: buf[len - 1] = type;
2849: sshbuf_reset(ssh->state->outgoing_packet);
2850: return sshbuf_put(ssh->state->outgoing_packet, buf, len);
2851: }
2852:
2853: /* send it */
2854:
2855: int
2856: sshpkt_send(struct ssh *ssh)
2857: {
2858: if (compat20)
2859: return ssh_packet_send2(ssh);
2860: else
2861: return ssh_packet_send1(ssh);
2862: }
2863:
2864: int
2865: sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2866: {
2867: char buf[1024];
2868: va_list args;
2869: int r;
2870:
2871: va_start(args, fmt);
2872: vsnprintf(buf, sizeof(buf), fmt, args);
2873: va_end(args);
2874:
2875: if (compat20) {
2876: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2877: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2878: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2879: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2880: (r = sshpkt_send(ssh)) != 0)
2881: return r;
2882: } else {
2883: if ((r = sshpkt_start(ssh, SSH_MSG_DISCONNECT)) != 0 ||
2884: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2885: (r = sshpkt_send(ssh)) != 0)
2886: return r;
1.166 andreas 2887: }
1.201 markus 2888: return 0;
2889: }
2890:
2891: /* roundup current message to pad bytes */
2892: int
2893: sshpkt_add_padding(struct ssh *ssh, u_char pad)
2894: {
2895: ssh->state->extra_pad = pad;
2896: return 0;
1.1 deraadt 2897: }
![[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