Annotation of src/usr.bin/ssh/packet.c, Revision 1.239
1.239 ! djm 1: /* $OpenBSD: packet.c,v 1.238 2016/09/19 19:02:19 markus Exp $ */
1.1 deraadt 2: /*
1.15 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.35 deraadt 6: * This file contains code implementing the packet protocol and communication
7: * with the other side. This same code is used both on client and server side.
1.29 markus 8: *
1.35 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
1.29 markus 14: *
1.25 markus 15: *
16: * SSH2 packet format added by Markus Friedl.
1.69 markus 17: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.25 markus 18: *
1.35 deraadt 19: * Redistribution and use in source and binary forms, with or without
20: * modification, are permitted provided that the following conditions
21: * are met:
22: * 1. Redistributions of source code must retain the above copyright
23: * notice, this list of conditions and the following disclaimer.
24: * 2. Redistributions in binary form must reproduce the above copyright
25: * notice, this list of conditions and the following disclaimer in the
26: * documentation and/or other materials provided with the distribution.
27: *
28: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
29: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
30: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
31: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
32: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
33: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
37: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.15 deraadt 38: */
1.1 deraadt 39:
1.142 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); */
1.118 markus 957: if ((comp->type == COMP_ZLIB ||
1.161 andreas 958: (comp->type == COMP_DELAYED &&
1.201 markus 959: state->after_authentication)) && comp->enabled == 0) {
960: if ((r = ssh_packet_init_compression(ssh)) < 0)
961: return r;
962: if (mode == MODE_OUT) {
963: if ((r = start_compression_out(ssh, 6)) != 0)
964: return r;
965: } else {
966: if ((r = start_compression_in(ssh)) != 0)
967: return r;
968: }
1.57 markus 969: comp->enabled = 1;
970: }
1.109 markus 971: /*
972: * The 2^(blocksize*2) limit is too expensive for 3DES,
973: * blowfish, etc, so enforce a 1GB limit for small blocksizes.
974: */
975: if (enc->block_size >= 16)
976: *max_blocks = (u_int64_t)1 << (enc->block_size*2);
977: else
978: *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1.201 markus 979: if (state->rekey_limit)
1.237 deraadt 980: *max_blocks = MINIMUM(*max_blocks,
1.201 markus 981: state->rekey_limit / enc->block_size);
1.227 djm 982: debug("rekey after %llu blocks", (unsigned long long)*max_blocks);
1.201 markus 983: return 0;
1.57 markus 984: }
985:
1.228 djm 986: #define MAX_PACKETS (1U<<31)
987: static int
988: ssh_packet_need_rekeying(struct ssh *ssh, u_int outbound_packet_len)
989: {
990: struct session_state *state = ssh->state;
991: u_int32_t out_blocks;
992:
993: /* XXX client can't cope with rekeying pre-auth */
994: if (!state->after_authentication)
995: return 0;
996:
997: /* Haven't keyed yet or KEX in progress. */
998: if (ssh->kex == NULL || ssh_packet_is_rekeying(ssh))
999: return 0;
1000:
1001: /* Peer can't rekey */
1002: if (ssh->compat & SSH_BUG_NOREKEY)
1003: return 0;
1004:
1005: /*
1006: * Permit one packet in or out per rekey - this allows us to
1007: * make progress when rekey limits are very small.
1008: */
1009: if (state->p_send.packets == 0 && state->p_read.packets == 0)
1010: return 0;
1011:
1012: /* Time-based rekeying */
1013: if (state->rekey_interval != 0 &&
1014: state->rekey_time + state->rekey_interval <= monotime())
1015: return 1;
1016:
1017: /* Always rekey when MAX_PACKETS sent in either direction */
1018: if (state->p_send.packets > MAX_PACKETS ||
1019: state->p_read.packets > MAX_PACKETS)
1020: return 1;
1021:
1022: /* Rekey after (cipher-specific) maxiumum blocks */
1.237 deraadt 1023: out_blocks = ROUNDUP(outbound_packet_len,
1.228 djm 1024: state->newkeys[MODE_OUT]->enc.block_size);
1025: return (state->max_blocks_out &&
1026: (state->p_send.blocks + out_blocks > state->max_blocks_out)) ||
1027: (state->max_blocks_in &&
1028: (state->p_read.blocks > state->max_blocks_in));
1029: }
1030:
1.16 markus 1031: /*
1.118 markus 1032: * Delayed compression for SSH2 is enabled after authentication:
1.143 dtucker 1033: * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1.118 markus 1034: * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
1035: */
1.201 markus 1036: static int
1037: ssh_packet_enable_delayed_compress(struct ssh *ssh)
1.118 markus 1038: {
1.201 markus 1039: struct session_state *state = ssh->state;
1040: struct sshcomp *comp = NULL;
1041: int r, mode;
1.118 markus 1042:
1043: /*
1044: * Remember that we are past the authentication step, so rekeying
1045: * with COMP_DELAYED will turn on compression immediately.
1046: */
1.201 markus 1047: state->after_authentication = 1;
1.118 markus 1048: for (mode = 0; mode < MODE_MAX; mode++) {
1.145 markus 1049: /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1.201 markus 1050: if (state->newkeys[mode] == NULL)
1.145 markus 1051: continue;
1.201 markus 1052: comp = &state->newkeys[mode]->comp;
1.118 markus 1053: if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1.201 markus 1054: if ((r = ssh_packet_init_compression(ssh)) != 0)
1055: return r;
1056: if (mode == MODE_OUT) {
1057: if ((r = start_compression_out(ssh, 6)) != 0)
1058: return r;
1059: } else {
1060: if ((r = start_compression_in(ssh)) != 0)
1061: return r;
1062: }
1.118 markus 1063: comp->enabled = 1;
1064: }
1065: }
1.201 markus 1066: return 0;
1.118 markus 1067: }
1068:
1.226 djm 1069: /* Used to mute debug logging for noisy packet types */
1070: static int
1071: ssh_packet_log_type(u_char type)
1072: {
1073: switch (type) {
1074: case SSH2_MSG_CHANNEL_DATA:
1075: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1076: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1077: return 0;
1078: default:
1079: return 1;
1080: }
1081: }
1082:
1.118 markus 1083: /*
1.25 markus 1084: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1085: */
1.201 markus 1086: int
1087: ssh_packet_send2_wrapped(struct ssh *ssh)
1.25 markus 1088: {
1.201 markus 1089: struct session_state *state = ssh->state;
1.200 markus 1090: u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1.233 djm 1091: u_char tmp, padlen, pad = 0;
1.201 markus 1092: u_int authlen = 0, aadlen = 0;
1093: u_int len;
1094: struct sshenc *enc = NULL;
1095: struct sshmac *mac = NULL;
1096: struct sshcomp *comp = NULL;
1097: int r, block_size;
1098:
1099: if (state->newkeys[MODE_OUT] != NULL) {
1100: enc = &state->newkeys[MODE_OUT]->enc;
1101: mac = &state->newkeys[MODE_OUT]->mac;
1102: comp = &state->newkeys[MODE_OUT]->comp;
1.180 markus 1103: /* disable mac for authenticated encryption */
1104: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1105: mac = NULL;
1.25 markus 1106: }
1.88 markus 1107: block_size = enc ? enc->block_size : 8;
1.180 markus 1108: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1109:
1.201 markus 1110: type = (sshbuf_ptr(state->outgoing_packet))[5];
1.226 djm 1111: if (ssh_packet_log_type(type))
1112: debug3("send packet: type %u", type);
1.25 markus 1113: #ifdef PACKET_DEBUG
1114: fprintf(stderr, "plain: ");
1.201 markus 1115: sshbuf_dump(state->outgoing_packet, stderr);
1.25 markus 1116: #endif
1117:
1118: if (comp && comp->enabled) {
1.201 markus 1119: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1120: /* skip header, compress only payload */
1.201 markus 1121: if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1122: goto out;
1123: sshbuf_reset(state->compression_buffer);
1124: if ((r = compress_buffer(ssh, state->outgoing_packet,
1125: state->compression_buffer)) != 0)
1126: goto out;
1127: sshbuf_reset(state->outgoing_packet);
1128: if ((r = sshbuf_put(state->outgoing_packet,
1129: "\0\0\0\0\0", 5)) != 0 ||
1130: (r = sshbuf_putb(state->outgoing_packet,
1131: state->compression_buffer)) != 0)
1132: goto out;
1133: DBG(debug("compression: raw %d compressed %zd", len,
1134: sshbuf_len(state->outgoing_packet)));
1.25 markus 1135: }
1136:
1137: /* sizeof (packet_len + pad_len + payload) */
1.201 markus 1138: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1139:
1140: /*
1141: * calc size of padding, alloc space, get random data,
1142: * minimum padding is 4 bytes
1143: */
1.178 markus 1144: len -= aadlen; /* packet length is not encrypted for EtM modes */
1.25 markus 1145: padlen = block_size - (len % block_size);
1146: if (padlen < 4)
1147: padlen += block_size;
1.201 markus 1148: if (state->extra_pad) {
1.233 djm 1149: tmp = state->extra_pad;
1.201 markus 1150: state->extra_pad =
1.237 deraadt 1151: ROUNDUP(state->extra_pad, block_size);
1.233 djm 1152: /* check if roundup overflowed */
1153: if (state->extra_pad < tmp)
1154: return SSH_ERR_INVALID_ARGUMENT;
1155: tmp = (len + padlen) % state->extra_pad;
1156: /* Check whether pad calculation below will underflow */
1157: if (tmp > state->extra_pad)
1158: return SSH_ERR_INVALID_ARGUMENT;
1159: pad = state->extra_pad - tmp;
1.193 djm 1160: DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1.201 markus 1161: __func__, pad, len, padlen, state->extra_pad));
1.233 djm 1162: tmp = padlen;
1.71 markus 1163: padlen += pad;
1.233 djm 1164: /* Check whether padlen calculation overflowed */
1165: if (padlen < tmp)
1166: return SSH_ERR_INVALID_ARGUMENT; /* overflow */
1.201 markus 1167: state->extra_pad = 0;
1.71 markus 1168: }
1.201 markus 1169: if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1170: goto out;
1.235 djm 1171: if (enc && !cipher_ctx_is_plaintext(state->send_context)) {
1.32 markus 1172: /* random padding */
1.201 markus 1173: arc4random_buf(cp, padlen);
1.32 markus 1174: } else {
1175: /* clear padding */
1.192 djm 1176: explicit_bzero(cp, padlen);
1.25 markus 1177: }
1.178 markus 1178: /* sizeof (packet_len + pad_len + payload + padding) */
1.201 markus 1179: len = sshbuf_len(state->outgoing_packet);
1180: cp = sshbuf_mutable_ptr(state->outgoing_packet);
1181: if (cp == NULL) {
1182: r = SSH_ERR_INTERNAL_ERROR;
1183: goto out;
1184: }
1.25 markus 1185: /* packet_length includes payload, padding and padding length field */
1.201 markus 1186: POKE_U32(cp, len - 4);
1.89 markus 1187: cp[4] = padlen;
1.178 markus 1188: DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1189: len, padlen, aadlen));
1.25 markus 1190:
1191: /* compute MAC over seqnr and packet(length fields, payload, padding) */
1.178 markus 1192: if (mac && mac->enabled && !mac->etm) {
1.201 markus 1193: if ((r = mac_compute(mac, state->p_send.seqnr,
1194: sshbuf_ptr(state->outgoing_packet), len,
1.200 markus 1195: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1196: goto out;
1197: DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1.25 markus 1198: }
1199: /* encrypt packet and append to output buffer. */
1.201 markus 1200: if ((r = sshbuf_reserve(state->output,
1201: sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1202: goto out;
1.235 djm 1203: if ((r = cipher_crypt(state->send_context, state->p_send.seqnr, cp,
1.201 markus 1204: sshbuf_ptr(state->outgoing_packet),
1205: len - aadlen, aadlen, authlen)) != 0)
1206: goto out;
1.25 markus 1207: /* append unencrypted MAC */
1.178 markus 1208: if (mac && mac->enabled) {
1209: if (mac->etm) {
1210: /* EtM: compute mac over aadlen + cipher text */
1.201 markus 1211: if ((r = mac_compute(mac, state->p_send.seqnr,
1212: cp, len, macbuf, sizeof(macbuf))) != 0)
1213: goto out;
1.178 markus 1214: DBG(debug("done calc MAC(EtM) out #%d",
1.201 markus 1215: state->p_send.seqnr));
1.178 markus 1216: }
1.201 markus 1217: if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1218: goto out;
1.178 markus 1219: }
1.25 markus 1220: #ifdef PACKET_DEBUG
1221: fprintf(stderr, "encrypted: ");
1.201 markus 1222: sshbuf_dump(state->output, stderr);
1.25 markus 1223: #endif
1.29 markus 1224: /* increment sequence number for outgoing packets */
1.201 markus 1225: if (++state->p_send.seqnr == 0)
1.106 itojun 1226: logit("outgoing seqnr wraps around");
1.201 markus 1227: if (++state->p_send.packets == 0)
1228: if (!(ssh->compat & SSH_BUG_NOREKEY))
1229: return SSH_ERR_NEED_REKEY;
1230: state->p_send.blocks += len / block_size;
1231: state->p_send.bytes += len;
1232: sshbuf_reset(state->outgoing_packet);
1.25 markus 1233:
1.57 markus 1234: if (type == SSH2_MSG_NEWKEYS)
1.201 markus 1235: r = ssh_set_newkeys(ssh, MODE_OUT);
1236: else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1237: r = ssh_packet_enable_delayed_compress(ssh);
1238: else
1239: r = 0;
1240: out:
1241: return r;
1.25 markus 1242: }
1243:
1.228 djm 1244: /* returns non-zero if the specified packet type is usec by KEX */
1245: static int
1246: ssh_packet_type_is_kex(u_char type)
1247: {
1248: return
1249: type >= SSH2_MSG_TRANSPORT_MIN &&
1250: type <= SSH2_MSG_TRANSPORT_MAX &&
1251: type != SSH2_MSG_SERVICE_REQUEST &&
1252: type != SSH2_MSG_SERVICE_ACCEPT &&
1253: type != SSH2_MSG_EXT_INFO;
1254: }
1255:
1.201 markus 1256: int
1257: ssh_packet_send2(struct ssh *ssh)
1.105 markus 1258: {
1.201 markus 1259: struct session_state *state = ssh->state;
1.105 markus 1260: struct packet *p;
1.201 markus 1261: u_char type;
1.228 djm 1262: int r, need_rekey;
1.105 markus 1263:
1.228 djm 1264: if (sshbuf_len(state->outgoing_packet) < 6)
1265: return SSH_ERR_INTERNAL_ERROR;
1.201 markus 1266: type = sshbuf_ptr(state->outgoing_packet)[5];
1.228 djm 1267: need_rekey = !ssh_packet_type_is_kex(type) &&
1268: ssh_packet_need_rekeying(ssh, sshbuf_len(state->outgoing_packet));
1.105 markus 1269:
1.228 djm 1270: /*
1271: * During rekeying we can only send key exchange messages.
1272: * Queue everything else.
1273: */
1274: if ((need_rekey || state->rekeying) && !ssh_packet_type_is_kex(type)) {
1275: if (need_rekey)
1276: debug3("%s: rekex triggered", __func__);
1277: debug("enqueue packet: %u", type);
1278: p = calloc(1, sizeof(*p));
1279: if (p == NULL)
1280: return SSH_ERR_ALLOC_FAIL;
1281: p->type = type;
1282: p->payload = state->outgoing_packet;
1283: TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1284: state->outgoing_packet = sshbuf_new();
1285: if (state->outgoing_packet == NULL)
1286: return SSH_ERR_ALLOC_FAIL;
1287: if (need_rekey) {
1288: /*
1289: * This packet triggered a rekey, so send the
1290: * KEXINIT now.
1291: * NB. reenters this function via kex_start_rekex().
1292: */
1293: return kex_start_rekex(ssh);
1.105 markus 1294: }
1.228 djm 1295: return 0;
1.105 markus 1296: }
1297:
1298: /* rekeying starts with sending KEXINIT */
1299: if (type == SSH2_MSG_KEXINIT)
1.201 markus 1300: state->rekeying = 1;
1.105 markus 1301:
1.201 markus 1302: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1303: return r;
1.105 markus 1304:
1305: /* after a NEWKEYS message we can send the complete queue */
1306: if (type == SSH2_MSG_NEWKEYS) {
1.201 markus 1307: state->rekeying = 0;
1308: state->rekey_time = monotime();
1309: while ((p = TAILQ_FIRST(&state->outgoing))) {
1.105 markus 1310: type = p->type;
1.228 djm 1311: /*
1312: * If this packet triggers a rekex, then skip the
1313: * remaining packets in the queue for now.
1314: * NB. re-enters this function via kex_start_rekex.
1315: */
1316: if (ssh_packet_need_rekeying(ssh,
1317: sshbuf_len(p->payload))) {
1318: debug3("%s: queued packet triggered rekex",
1319: __func__);
1320: return kex_start_rekex(ssh);
1321: }
1.105 markus 1322: debug("dequeue packet: %u", type);
1.201 markus 1323: sshbuf_free(state->outgoing_packet);
1324: state->outgoing_packet = p->payload;
1325: TAILQ_REMOVE(&state->outgoing, p, next);
1.228 djm 1326: memset(p, 0, sizeof(*p));
1.186 djm 1327: free(p);
1.201 markus 1328: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1329: return r;
1.105 markus 1330: }
1331: }
1.201 markus 1332: return 0;
1.25 markus 1333: }
1334:
1335: /*
1.16 markus 1336: * Waits until a packet has been received, and returns its type. Note that
1337: * no other data is processed until this returns, so this function should not
1338: * be used during the interactive session.
1339: */
1.1 deraadt 1340:
1.2 provos 1341: int
1.201 markus 1342: ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.1 deraadt 1343: {
1.201 markus 1344: struct session_state *state = ssh->state;
1.222 markus 1345: int len, r, ms_remain;
1.56 millert 1346: fd_set *setp;
1.14 markus 1347: char buf[8192];
1.155 deraadt 1348: struct timeval timeout, start, *timeoutp = NULL;
1349:
1.25 markus 1350: DBG(debug("packet_read()"));
1.14 markus 1351:
1.214 deraadt 1352: setp = calloc(howmany(state->connection_in + 1,
1.161 andreas 1353: NFDBITS), sizeof(fd_mask));
1.201 markus 1354: if (setp == NULL)
1355: return SSH_ERR_ALLOC_FAIL;
1.56 millert 1356:
1.205 djm 1357: /*
1358: * Since we are blocking, ensure that all written packets have
1359: * been sent.
1360: */
1.210 markus 1361: if ((r = ssh_packet_write_wait(ssh)) != 0)
1362: goto out;
1.14 markus 1363:
1364: /* Stay in the loop until we have received a complete packet. */
1365: for (;;) {
1366: /* Try to read a packet from the buffer. */
1.201 markus 1367: r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1368: if (r != 0)
1369: break;
1.62 markus 1370: if (!compat20 && (
1.201 markus 1371: *typep == SSH_SMSG_SUCCESS
1372: || *typep == SSH_SMSG_FAILURE
1373: || *typep == SSH_CMSG_EOF
1374: || *typep == SSH_CMSG_EXIT_CONFIRMATION))
1375: if ((r = sshpkt_get_end(ssh)) != 0)
1376: break;
1.14 markus 1377: /* If we got a packet, return it. */
1.201 markus 1378: if (*typep != SSH_MSG_NONE)
1379: break;
1.16 markus 1380: /*
1381: * Otherwise, wait for some data to arrive, add it to the
1382: * buffer, and try again.
1383: */
1.201 markus 1384: memset(setp, 0, howmany(state->connection_in + 1,
1.161 andreas 1385: NFDBITS) * sizeof(fd_mask));
1.201 markus 1386: FD_SET(state->connection_in, setp);
1.16 markus 1387:
1.201 markus 1388: if (state->packet_timeout_ms > 0) {
1389: ms_remain = state->packet_timeout_ms;
1.154 dtucker 1390: timeoutp = &timeout;
1391: }
1.14 markus 1392: /* Wait for some data to arrive. */
1.154 dtucker 1393: for (;;) {
1.201 markus 1394: if (state->packet_timeout_ms != -1) {
1.154 dtucker 1395: ms_to_timeval(&timeout, ms_remain);
1396: gettimeofday(&start, NULL);
1397: }
1.201 markus 1398: if ((r = select(state->connection_in + 1, setp,
1.161 andreas 1399: NULL, NULL, timeoutp)) >= 0)
1.154 dtucker 1400: break;
1.161 andreas 1401: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 1402: break;
1.201 markus 1403: if (state->packet_timeout_ms == -1)
1.154 dtucker 1404: continue;
1405: ms_subtract_diff(&start, &ms_remain);
1406: if (ms_remain <= 0) {
1.201 markus 1407: r = 0;
1.154 dtucker 1408: break;
1409: }
1410: }
1.204 djm 1411: if (r == 0)
1412: return SSH_ERR_CONN_TIMEOUT;
1.14 markus 1413: /* Read data from the socket. */
1.222 markus 1414: len = read(state->connection_in, buf, sizeof(buf));
1.210 markus 1415: if (len == 0) {
1416: r = SSH_ERR_CONN_CLOSED;
1417: goto out;
1418: }
1419: if (len < 0) {
1420: r = SSH_ERR_SYSTEM_ERROR;
1421: goto out;
1422: }
1.204 djm 1423:
1.14 markus 1424: /* Append it to the buffer. */
1.204 djm 1425: if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1.210 markus 1426: goto out;
1.14 markus 1427: }
1.210 markus 1428: out:
1.201 markus 1429: free(setp);
1430: return r;
1.1 deraadt 1431: }
1432:
1.77 djm 1433: int
1.201 markus 1434: ssh_packet_read(struct ssh *ssh)
1.77 djm 1435: {
1.201 markus 1436: u_char type;
1437: int r;
1438:
1439: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1440: fatal("%s: %s", __func__, ssh_err(r));
1441: return type;
1.77 djm 1442: }
1443:
1.16 markus 1444: /*
1445: * Waits until a packet has been received, verifies that its type matches
1446: * that given, and gives a fatal error and exits if there is a mismatch.
1447: */
1.1 deraadt 1448:
1.205 djm 1449: int
1450: ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1.1 deraadt 1451: {
1.205 djm 1452: int r;
1453: u_char type;
1.1 deraadt 1454:
1.205 djm 1455: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1456: return r;
1457: if (type != expected_type) {
1458: if ((r = sshpkt_disconnect(ssh,
1.201 markus 1459: "Protocol error: expected packet type %d, got %d",
1.205 djm 1460: expected_type, type)) != 0)
1461: return r;
1462: return SSH_ERR_PROTOCOL_ERROR;
1463: }
1464: return 0;
1.1 deraadt 1465: }
1466:
1467: /* Checks if a full packet is available in the data received so far via
1.14 markus 1468: * packet_process_incoming. If so, reads the packet; otherwise returns
1469: * SSH_MSG_NONE. This does not wait for data from the connection.
1470: *
1.150 dtucker 1471: * SSH_MSG_DISCONNECT is handled specially here. Also,
1472: * SSH_MSG_IGNORE messages are skipped by this function and are never returned
1473: * to higher levels.
1.14 markus 1474: */
1.1 deraadt 1475:
1.201 markus 1476: int
1477: ssh_packet_read_poll1(struct ssh *ssh, u_char *typep)
1.1 deraadt 1478: {
1.201 markus 1479: struct session_state *state = ssh->state;
1.40 markus 1480: u_int len, padded_len;
1.205 djm 1481: const char *emsg;
1.201 markus 1482: const u_char *cp;
1483: u_char *p;
1.40 markus 1484: u_int checksum, stored_checksum;
1.201 markus 1485: int r;
1486:
1487: *typep = SSH_MSG_NONE;
1.14 markus 1488:
1489: /* Check if input size is less than minimum packet size. */
1.201 markus 1490: if (sshbuf_len(state->input) < 4 + 8)
1491: return 0;
1.14 markus 1492: /* Get length of incoming packet. */
1.201 markus 1493: len = PEEK_U32(sshbuf_ptr(state->input));
1.205 djm 1494: if (len < 1 + 2 + 2 || len > 256 * 1024) {
1495: if ((r = sshpkt_disconnect(ssh, "Bad packet length %u",
1496: len)) != 0)
1497: return r;
1498: return SSH_ERR_CONN_CORRUPT;
1499: }
1.14 markus 1500: padded_len = (len + 8) & ~7;
1501:
1502: /* Check if the packet has been entirely received. */
1.201 markus 1503: if (sshbuf_len(state->input) < 4 + padded_len)
1504: return 0;
1.14 markus 1505:
1506: /* The entire packet is in buffer. */
1507:
1508: /* Consume packet length. */
1.201 markus 1509: if ((r = sshbuf_consume(state->input, 4)) != 0)
1510: goto out;
1.14 markus 1511:
1.62 markus 1512: /*
1513: * Cryptographic attack detector for ssh
1514: * (C)1998 CORE-SDI, Buenos Aires Argentina
1515: * Ariel Futoransky(futo@core-sdi.com)
1516: */
1.235 djm 1517: if (!cipher_ctx_is_plaintext(state->receive_context)) {
1.205 djm 1518: emsg = NULL;
1.201 markus 1519: switch (detect_attack(&state->deattack,
1520: sshbuf_ptr(state->input), padded_len)) {
1521: case DEATTACK_OK:
1522: break;
1.144 djm 1523: case DEATTACK_DETECTED:
1.205 djm 1524: emsg = "crc32 compensation attack detected";
1525: break;
1.144 djm 1526: case DEATTACK_DOS_DETECTED:
1.205 djm 1527: emsg = "deattack denial of service detected";
1528: break;
1.201 markus 1529: default:
1.205 djm 1530: emsg = "deattack error";
1531: break;
1532: }
1533: if (emsg != NULL) {
1534: error("%s", emsg);
1535: if ((r = sshpkt_disconnect(ssh, "%s", emsg)) != 0 ||
1536: (r = ssh_packet_write_wait(ssh)) != 0)
1537: return r;
1538: return SSH_ERR_CONN_CORRUPT;
1.144 djm 1539: }
1540: }
1.62 markus 1541:
1542: /* Decrypt data to incoming_packet. */
1.201 markus 1543: sshbuf_reset(state->incoming_packet);
1544: if ((r = sshbuf_reserve(state->incoming_packet, padded_len, &p)) != 0)
1545: goto out;
1.235 djm 1546: if ((r = cipher_crypt(state->receive_context, 0, p,
1.201 markus 1547: sshbuf_ptr(state->input), padded_len, 0, 0)) != 0)
1548: goto out;
1.62 markus 1549:
1.201 markus 1550: if ((r = sshbuf_consume(state->input, padded_len)) != 0)
1551: goto out;
1.1 deraadt 1552:
1553: #ifdef PACKET_DEBUG
1.14 markus 1554: fprintf(stderr, "read_poll plain: ");
1.201 markus 1555: sshbuf_dump(state->incoming_packet, stderr);
1.1 deraadt 1556: #endif
1557:
1.14 markus 1558: /* Compute packet checksum. */
1.201 markus 1559: checksum = ssh_crc32(sshbuf_ptr(state->incoming_packet),
1560: sshbuf_len(state->incoming_packet) - 4);
1.14 markus 1561:
1562: /* Skip padding. */
1.201 markus 1563: if ((r = sshbuf_consume(state->incoming_packet, 8 - len % 8)) != 0)
1564: goto out;
1.14 markus 1565:
1566: /* Test check bytes. */
1.205 djm 1567: if (len != sshbuf_len(state->incoming_packet)) {
1568: error("%s: len %d != sshbuf_len %zd", __func__,
1.201 markus 1569: len, sshbuf_len(state->incoming_packet));
1.205 djm 1570: if ((r = sshpkt_disconnect(ssh, "invalid packet length")) != 0 ||
1571: (r = ssh_packet_write_wait(ssh)) != 0)
1572: return r;
1573: return SSH_ERR_CONN_CORRUPT;
1574: }
1.14 markus 1575:
1.201 markus 1576: cp = sshbuf_ptr(state->incoming_packet) + len - 4;
1577: stored_checksum = PEEK_U32(cp);
1.205 djm 1578: if (checksum != stored_checksum) {
1579: error("Corrupted check bytes on input");
1580: if ((r = sshpkt_disconnect(ssh, "connection corrupted")) != 0 ||
1581: (r = ssh_packet_write_wait(ssh)) != 0)
1582: return r;
1583: return SSH_ERR_CONN_CORRUPT;
1584: }
1.201 markus 1585: if ((r = sshbuf_consume_end(state->incoming_packet, 4)) < 0)
1586: goto out;
1587:
1588: if (state->packet_compression) {
1589: sshbuf_reset(state->compression_buffer);
1590: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1591: state->compression_buffer)) != 0)
1592: goto out;
1593: sshbuf_reset(state->incoming_packet);
1594: if ((r = sshbuf_putb(state->incoming_packet,
1595: state->compression_buffer)) != 0)
1596: goto out;
1597: }
1598: state->p_read.packets++;
1599: state->p_read.bytes += padded_len + 4;
1600: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1601: goto out;
1.205 djm 1602: if (*typep < SSH_MSG_MIN || *typep > SSH_MSG_MAX) {
1603: error("Invalid ssh1 packet type: %d", *typep);
1604: if ((r = sshpkt_disconnect(ssh, "invalid packet type")) != 0 ||
1605: (r = ssh_packet_write_wait(ssh)) != 0)
1606: return r;
1607: return SSH_ERR_PROTOCOL_ERROR;
1608: }
1.201 markus 1609: r = 0;
1610: out:
1611: return r;
1.1 deraadt 1612: }
1.14 markus 1613:
1.201 markus 1614: int
1615: ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1616: {
1.201 markus 1617: struct session_state *state = ssh->state;
1.40 markus 1618: u_int padlen, need;
1.231 djm 1619: u_char *cp;
1.201 markus 1620: u_int maclen, aadlen = 0, authlen = 0, block_size;
1621: struct sshenc *enc = NULL;
1622: struct sshmac *mac = NULL;
1623: struct sshcomp *comp = NULL;
1.200 markus 1624: int r;
1.201 markus 1625:
1626: *typep = SSH_MSG_NONE;
1627:
1628: if (state->packet_discard)
1629: return 0;
1630:
1631: if (state->newkeys[MODE_IN] != NULL) {
1632: enc = &state->newkeys[MODE_IN]->enc;
1633: mac = &state->newkeys[MODE_IN]->mac;
1634: comp = &state->newkeys[MODE_IN]->comp;
1.180 markus 1635: /* disable mac for authenticated encryption */
1636: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1637: mac = NULL;
1.25 markus 1638: }
1639: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.88 markus 1640: block_size = enc ? enc->block_size : 8;
1.180 markus 1641: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1642:
1.201 markus 1643: if (aadlen && state->packlen == 0) {
1.235 djm 1644: if (cipher_get_length(state->receive_context,
1.201 markus 1645: &state->packlen, state->p_read.seqnr,
1646: sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1647: return 0;
1648: if (state->packlen < 1 + 4 ||
1649: state->packlen > PACKET_MAX_SIZE) {
1.178 markus 1650: #ifdef PACKET_DEBUG
1.201 markus 1651: sshbuf_dump(state->input, stderr);
1.178 markus 1652: #endif
1.201 markus 1653: logit("Bad packet length %u.", state->packlen);
1654: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1655: return r;
1.217 djm 1656: return SSH_ERR_CONN_CORRUPT;
1.178 markus 1657: }
1.201 markus 1658: sshbuf_reset(state->incoming_packet);
1659: } else if (state->packlen == 0) {
1.25 markus 1660: /*
1661: * check if input size is less than the cipher block size,
1662: * decrypt first block and extract length of incoming packet
1663: */
1.201 markus 1664: if (sshbuf_len(state->input) < block_size)
1665: return 0;
1666: sshbuf_reset(state->incoming_packet);
1667: if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1668: &cp)) != 0)
1669: goto out;
1.235 djm 1670: if ((r = cipher_crypt(state->receive_context,
1.201 markus 1671: state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1672: block_size, 0, 0)) != 0)
1673: goto out;
1674: state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1675: if (state->packlen < 1 + 4 ||
1676: state->packlen > PACKET_MAX_SIZE) {
1.110 markus 1677: #ifdef PACKET_DEBUG
1.201 markus 1678: fprintf(stderr, "input: \n");
1679: sshbuf_dump(state->input, stderr);
1680: fprintf(stderr, "incoming_packet: \n");
1681: sshbuf_dump(state->incoming_packet, stderr);
1.110 markus 1682: #endif
1.201 markus 1683: logit("Bad packet length %u.", state->packlen);
1.234 markus 1684: return ssh_packet_start_discard(ssh, enc, mac, 0,
1685: PACKET_MAX_SIZE);
1.25 markus 1686: }
1.201 markus 1687: if ((r = sshbuf_consume(state->input, block_size)) != 0)
1688: goto out;
1.25 markus 1689: }
1.201 markus 1690: DBG(debug("input: packet len %u", state->packlen+4));
1691:
1.178 markus 1692: if (aadlen) {
1693: /* only the payload is encrypted */
1.201 markus 1694: need = state->packlen;
1.178 markus 1695: } else {
1696: /*
1697: * the payload size and the payload are encrypted, but we
1698: * have a partial packet of block_size bytes
1699: */
1.201 markus 1700: need = 4 + state->packlen - block_size;
1.178 markus 1701: }
1.180 markus 1702: DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1703: " aadlen %d", block_size, need, maclen, authlen, aadlen));
1.158 markus 1704: if (need % block_size != 0) {
1705: logit("padding error: need %d block %d mod %d",
1.25 markus 1706: need, block_size, need % block_size);
1.234 markus 1707: return ssh_packet_start_discard(ssh, enc, mac, 0,
1708: PACKET_MAX_SIZE - block_size);
1.158 markus 1709: }
1.25 markus 1710: /*
1711: * check if the entire packet has been received and
1.178 markus 1712: * decrypt into incoming_packet:
1713: * 'aadlen' bytes are unencrypted, but authenticated.
1.180 markus 1714: * 'need' bytes are encrypted, followed by either
1715: * 'authlen' bytes of authentication tag or
1.178 markus 1716: * 'maclen' bytes of message authentication code.
1.25 markus 1717: */
1.201 markus 1718: if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1.231 djm 1719: return 0; /* packet is incomplete */
1.25 markus 1720: #ifdef PACKET_DEBUG
1721: fprintf(stderr, "read_poll enc/full: ");
1.201 markus 1722: sshbuf_dump(state->input, stderr);
1.25 markus 1723: #endif
1.231 djm 1724: /* EtM: check mac over encrypted input */
1.201 markus 1725: if (mac && mac->enabled && mac->etm) {
1.231 djm 1726: if ((r = mac_check(mac, state->p_read.seqnr,
1.201 markus 1727: sshbuf_ptr(state->input), aadlen + need,
1.231 djm 1728: sshbuf_ptr(state->input) + aadlen + need + authlen,
1729: maclen)) != 0) {
1730: if (r == SSH_ERR_MAC_INVALID)
1731: logit("Corrupted MAC on input.");
1.201 markus 1732: goto out;
1.231 djm 1733: }
1.201 markus 1734: }
1735: if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1736: &cp)) != 0)
1737: goto out;
1.235 djm 1738: if ((r = cipher_crypt(state->receive_context, state->p_read.seqnr, cp,
1.201 markus 1739: sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1740: goto out;
1741: if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1742: goto out;
1.29 markus 1743: if (mac && mac->enabled) {
1.231 djm 1744: /* Not EtM: check MAC over cleartext */
1745: if (!mac->etm && (r = mac_check(mac, state->p_read.seqnr,
1746: sshbuf_ptr(state->incoming_packet),
1747: sshbuf_len(state->incoming_packet),
1748: sshbuf_ptr(state->input), maclen)) != 0) {
1749: if (r != SSH_ERR_MAC_INVALID)
1.201 markus 1750: goto out;
1.159 markus 1751: logit("Corrupted MAC on input.");
1752: if (need > PACKET_MAX_SIZE)
1.201 markus 1753: return SSH_ERR_INTERNAL_ERROR;
1754: return ssh_packet_start_discard(ssh, enc, mac,
1.234 markus 1755: sshbuf_len(state->incoming_packet),
1756: PACKET_MAX_SIZE - need);
1.201 markus 1757: }
1.231 djm 1758: /* Remove MAC from input buffer */
1.201 markus 1759: DBG(debug("MAC #%d ok", state->p_read.seqnr));
1760: if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1761: goto out;
1.25 markus 1762: }
1.77 djm 1763: if (seqnr_p != NULL)
1.201 markus 1764: *seqnr_p = state->p_read.seqnr;
1765: if (++state->p_read.seqnr == 0)
1.106 itojun 1766: logit("incoming seqnr wraps around");
1.201 markus 1767: if (++state->p_read.packets == 0)
1768: if (!(ssh->compat & SSH_BUG_NOREKEY))
1769: return SSH_ERR_NEED_REKEY;
1770: state->p_read.blocks += (state->packlen + 4) / block_size;
1771: state->p_read.bytes += state->packlen + 4;
1.25 markus 1772:
1773: /* get padlen */
1.201 markus 1774: padlen = sshbuf_ptr(state->incoming_packet)[4];
1.25 markus 1775: DBG(debug("input: padlen %d", padlen));
1.205 djm 1776: if (padlen < 4) {
1777: if ((r = sshpkt_disconnect(ssh,
1778: "Corrupted padlen %d on input.", padlen)) != 0 ||
1779: (r = ssh_packet_write_wait(ssh)) != 0)
1780: return r;
1781: return SSH_ERR_CONN_CORRUPT;
1782: }
1.25 markus 1783:
1784: /* skip packet size + padlen, discard padding */
1.201 markus 1785: if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1786: ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1787: goto out;
1.25 markus 1788:
1.201 markus 1789: DBG(debug("input: len before de-compress %zd",
1790: sshbuf_len(state->incoming_packet)));
1.25 markus 1791: if (comp && comp->enabled) {
1.201 markus 1792: sshbuf_reset(state->compression_buffer);
1793: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1794: state->compression_buffer)) != 0)
1795: goto out;
1796: sshbuf_reset(state->incoming_packet);
1797: if ((r = sshbuf_putb(state->incoming_packet,
1798: state->compression_buffer)) != 0)
1799: goto out;
1800: DBG(debug("input: len after de-compress %zd",
1801: sshbuf_len(state->incoming_packet)));
1.25 markus 1802: }
1803: /*
1804: * get packet type, implies consume.
1805: * return length of payload (without type field)
1806: */
1.201 markus 1807: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1808: goto out;
1.226 djm 1809: if (ssh_packet_log_type(*typep))
1810: debug3("receive packet: type %u", *typep);
1.205 djm 1811: if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1812: if ((r = sshpkt_disconnect(ssh,
1813: "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1814: (r = ssh_packet_write_wait(ssh)) != 0)
1815: return r;
1816: return SSH_ERR_PROTOCOL_ERROR;
1817: }
1.238 markus 1818: if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1.201 markus 1819: r = ssh_packet_enable_delayed_compress(ssh);
1820: else
1821: r = 0;
1.25 markus 1822: #ifdef PACKET_DEBUG
1.201 markus 1823: fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1824: sshbuf_dump(state->incoming_packet, stderr);
1.25 markus 1825: #endif
1.62 markus 1826: /* reset for next packet */
1.201 markus 1827: state->packlen = 0;
1.228 djm 1828:
1829: /* do we need to rekey? */
1830: if (ssh_packet_need_rekeying(ssh, 0)) {
1831: debug3("%s: rekex triggered", __func__);
1832: if ((r = kex_start_rekex(ssh)) != 0)
1833: return r;
1834: }
1.201 markus 1835: out:
1836: return r;
1.25 markus 1837: }
1838:
1839: int
1.201 markus 1840: ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1841: {
1.201 markus 1842: struct session_state *state = ssh->state;
1.96 deraadt 1843: u_int reason, seqnr;
1.201 markus 1844: int r;
1845: u_char *msg;
1.62 markus 1846:
1.25 markus 1847: for (;;) {
1.201 markus 1848: msg = NULL;
1.62 markus 1849: if (compat20) {
1.201 markus 1850: r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1851: if (r != 0)
1852: return r;
1853: if (*typep) {
1854: state->keep_alive_timeouts = 0;
1855: DBG(debug("received packet type %d", *typep));
1.153 djm 1856: }
1.201 markus 1857: switch (*typep) {
1.150 dtucker 1858: case SSH2_MSG_IGNORE:
1.151 dtucker 1859: debug3("Received SSH2_MSG_IGNORE");
1.150 dtucker 1860: break;
1.25 markus 1861: case SSH2_MSG_DEBUG:
1.201 markus 1862: if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1863: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1864: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1.219 mmcc 1865: free(msg);
1.201 markus 1866: return r;
1867: }
1.25 markus 1868: debug("Remote: %.900s", msg);
1.186 djm 1869: free(msg);
1.25 markus 1870: break;
1871: case SSH2_MSG_DISCONNECT:
1.201 markus 1872: if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
1873: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1874: return r;
1.182 djm 1875: /* Ignore normal client exit notifications */
1.201 markus 1876: do_log2(ssh->state->server_side &&
1.182 djm 1877: reason == SSH2_DISCONNECT_BY_APPLICATION ?
1878: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
1.220 djm 1879: "Received disconnect from %s port %d:"
1880: "%u: %.400s", ssh_remote_ipaddr(ssh),
1881: ssh_remote_port(ssh), reason, msg);
1.186 djm 1882: free(msg);
1.201 markus 1883: return SSH_ERR_DISCONNECTED;
1.84 markus 1884: case SSH2_MSG_UNIMPLEMENTED:
1.201 markus 1885: if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1886: return r;
1.96 deraadt 1887: debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1888: seqnr);
1.150 dtucker 1889: break;
1.25 markus 1890: default:
1.201 markus 1891: return 0;
1.48 stevesk 1892: }
1.25 markus 1893: } else {
1.201 markus 1894: r = ssh_packet_read_poll1(ssh, typep);
1895: switch (*typep) {
1.188 djm 1896: case SSH_MSG_NONE:
1897: return SSH_MSG_NONE;
1.25 markus 1898: case SSH_MSG_IGNORE:
1899: break;
1900: case SSH_MSG_DEBUG:
1.201 markus 1901: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1902: return r;
1.25 markus 1903: debug("Remote: %.900s", msg);
1.186 djm 1904: free(msg);
1.25 markus 1905: break;
1906: case SSH_MSG_DISCONNECT:
1.201 markus 1907: if ((r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
1908: return r;
1.220 djm 1909: error("Received disconnect from %s port %d: "
1910: "%.400s", ssh_remote_ipaddr(ssh),
1911: ssh_remote_port(ssh), msg);
1.201 markus 1912: free(msg);
1913: return SSH_ERR_DISCONNECTED;
1.25 markus 1914: default:
1.201 markus 1915: DBG(debug("received packet type %d", *typep));
1916: return 0;
1.48 stevesk 1917: }
1.25 markus 1918: }
1919: }
1920: }
1921:
1.16 markus 1922: /*
1923: * Buffers the given amount of input characters. This is intended to be used
1924: * together with packet_read_poll.
1925: */
1.1 deraadt 1926:
1.204 djm 1927: int
1.201 markus 1928: ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1.1 deraadt 1929: {
1.201 markus 1930: struct session_state *state = ssh->state;
1931: int r;
1932:
1933: if (state->packet_discard) {
1934: state->keep_alive_timeouts = 0; /* ?? */
1935: if (len >= state->packet_discard) {
1936: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1.204 djm 1937: return r;
1.201 markus 1938: }
1939: state->packet_discard -= len;
1.204 djm 1940: return 0;
1.159 markus 1941: }
1.201 markus 1942: if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1.204 djm 1943: return r;
1944:
1945: return 0;
1.28 markus 1946: }
1947:
1948: int
1.201 markus 1949: ssh_packet_remaining(struct ssh *ssh)
1.28 markus 1950: {
1.201 markus 1951: return sshbuf_len(ssh->state->incoming_packet);
1.1 deraadt 1952: }
1953:
1.16 markus 1954: /*
1955: * Sends a diagnostic message from the server to the client. This message
1956: * can be sent at any time (but not while constructing another message). The
1957: * message is printed immediately, but only if the client is being executed
1958: * in verbose mode. These messages are primarily intended to ease debugging
1959: * authentication problems. The length of the formatted message must not
1.205 djm 1960: * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1.16 markus 1961: */
1.2 provos 1962: void
1.201 markus 1963: ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1964: {
1.14 markus 1965: char buf[1024];
1966: va_list args;
1.201 markus 1967: int r;
1.39 markus 1968:
1.201 markus 1969: if (compat20 && (ssh->compat & SSH_BUG_DEBUG))
1.39 markus 1970: return;
1.14 markus 1971:
1972: va_start(args, fmt);
1973: vsnprintf(buf, sizeof(buf), fmt, args);
1974: va_end(args);
1975:
1.30 markus 1976: if (compat20) {
1.201 markus 1977: if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1978: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1979: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1980: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1981: (r = sshpkt_send(ssh)) != 0)
1982: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1983: } else {
1.201 markus 1984: if ((r = sshpkt_start(ssh, SSH_MSG_DEBUG)) != 0 ||
1985: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1986: (r = sshpkt_send(ssh)) != 0)
1987: fatal("%s: %s", __func__, ssh_err(r));
1.30 markus 1988: }
1.205 djm 1989: if ((r = ssh_packet_write_wait(ssh)) != 0)
1990: fatal("%s: %s", __func__, ssh_err(r));
1991: }
1992:
1993: /*
1994: * Pretty-print connection-terminating errors and exit.
1995: */
1996: void
1997: sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1998: {
1999: switch (r) {
2000: case SSH_ERR_CONN_CLOSED:
1.232 dtucker 2001: logdie("Connection closed by %.200s port %d",
1.220 djm 2002: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.205 djm 2003: case SSH_ERR_CONN_TIMEOUT:
1.232 dtucker 2004: logdie("Connection %s %.200s port %d timed out",
1.220 djm 2005: ssh->state->server_side ? "from" : "to",
2006: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 2007: case SSH_ERR_DISCONNECTED:
1.232 dtucker 2008: logdie("Disconnected from %.200s port %d",
1.220 djm 2009: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.212 djm 2010: case SSH_ERR_SYSTEM_ERROR:
1.232 dtucker 2011: if (errno == ECONNRESET)
2012: logdie("Connection reset by %.200s port %d",
1.220 djm 2013: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.213 djm 2014: /* FALLTHROUGH */
2015: case SSH_ERR_NO_CIPHER_ALG_MATCH:
2016: case SSH_ERR_NO_MAC_ALG_MATCH:
2017: case SSH_ERR_NO_COMPRESS_ALG_MATCH:
2018: case SSH_ERR_NO_KEX_ALG_MATCH:
2019: case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
2020: if (ssh && ssh->kex && ssh->kex->failed_choice) {
1.232 dtucker 2021: logdie("Unable to negotiate with %.200s port %d: %s. "
1.213 djm 2022: "Their offer: %s", ssh_remote_ipaddr(ssh),
1.220 djm 2023: ssh_remote_port(ssh), ssh_err(r),
2024: ssh->kex->failed_choice);
1.212 djm 2025: }
2026: /* FALLTHROUGH */
1.205 djm 2027: default:
1.232 dtucker 2028: logdie("%s%sConnection %s %.200s port %d: %s",
1.205 djm 2029: tag != NULL ? tag : "", tag != NULL ? ": " : "",
1.220 djm 2030: ssh->state->server_side ? "from" : "to",
2031: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), ssh_err(r));
1.205 djm 2032: }
1.1 deraadt 2033: }
2034:
1.16 markus 2035: /*
2036: * Logs the error plus constructs and sends a disconnect packet, closes the
2037: * connection, and exits. This function never returns. The error message
2038: * should not contain a newline. The length of the formatted message must
2039: * not exceed 1024 bytes.
2040: */
1.2 provos 2041: void
1.201 markus 2042: ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 2043: {
1.14 markus 2044: char buf[1024];
2045: va_list args;
2046: static int disconnecting = 0;
1.201 markus 2047: int r;
1.97 deraadt 2048:
1.14 markus 2049: if (disconnecting) /* Guard against recursive invocations. */
2050: fatal("packet_disconnect called recursively.");
2051: disconnecting = 1;
2052:
1.16 markus 2053: /*
2054: * Format the message. Note that the caller must make sure the
2055: * message is of limited size.
2056: */
1.14 markus 2057: va_start(args, fmt);
2058: vsnprintf(buf, sizeof(buf), fmt, args);
2059: va_end(args);
2060:
1.99 markus 2061: /* Display the error locally */
1.106 itojun 2062: logit("Disconnecting: %.100s", buf);
1.99 markus 2063:
1.205 djm 2064: /*
2065: * Send the disconnect message to the other side, and wait
2066: * for it to get sent.
2067: */
2068: if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
2069: sshpkt_fatal(ssh, __func__, r);
2070:
2071: if ((r = ssh_packet_write_wait(ssh)) != 0)
2072: sshpkt_fatal(ssh, __func__, r);
1.14 markus 2073:
2074: /* Close the connection. */
1.201 markus 2075: ssh_packet_close(ssh);
1.112 markus 2076: cleanup_exit(255);
1.1 deraadt 2077: }
2078:
1.205 djm 2079: /*
2080: * Checks if there is any buffered output, and tries to write some of
2081: * the output.
2082: */
2083: int
1.201 markus 2084: ssh_packet_write_poll(struct ssh *ssh)
1.1 deraadt 2085: {
1.201 markus 2086: struct session_state *state = ssh->state;
2087: int len = sshbuf_len(state->output);
1.222 markus 2088: int r;
1.97 deraadt 2089:
1.14 markus 2090: if (len > 0) {
1.222 markus 2091: len = write(state->connection_out,
2092: sshbuf_ptr(state->output), len);
1.156 djm 2093: if (len == -1) {
2094: if (errno == EINTR || errno == EAGAIN)
1.205 djm 2095: return 0;
2096: return SSH_ERR_SYSTEM_ERROR;
1.14 markus 2097: }
1.222 markus 2098: if (len == 0)
1.205 djm 2099: return SSH_ERR_CONN_CLOSED;
1.201 markus 2100: if ((r = sshbuf_consume(state->output, len)) != 0)
1.205 djm 2101: return r;
1.14 markus 2102: }
1.205 djm 2103: return 0;
1.1 deraadt 2104: }
2105:
1.16 markus 2106: /*
2107: * Calls packet_write_poll repeatedly until all pending output data has been
2108: * written.
2109: */
1.205 djm 2110: int
1.201 markus 2111: ssh_packet_write_wait(struct ssh *ssh)
1.1 deraadt 2112: {
1.56 millert 2113: fd_set *setp;
1.205 djm 2114: int ret, r, ms_remain = 0;
1.154 dtucker 2115: struct timeval start, timeout, *timeoutp = NULL;
1.201 markus 2116: struct session_state *state = ssh->state;
1.56 millert 2117:
1.214 deraadt 2118: setp = calloc(howmany(state->connection_out + 1,
1.161 andreas 2119: NFDBITS), sizeof(fd_mask));
1.201 markus 2120: if (setp == NULL)
1.205 djm 2121: return SSH_ERR_ALLOC_FAIL;
1.216 gsoares 2122: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2123: free(setp);
1.215 djm 2124: return r;
1.216 gsoares 2125: }
1.201 markus 2126: while (ssh_packet_have_data_to_write(ssh)) {
2127: memset(setp, 0, howmany(state->connection_out + 1,
1.161 andreas 2128: NFDBITS) * sizeof(fd_mask));
1.201 markus 2129: FD_SET(state->connection_out, setp);
1.154 dtucker 2130:
1.201 markus 2131: if (state->packet_timeout_ms > 0) {
2132: ms_remain = state->packet_timeout_ms;
1.154 dtucker 2133: timeoutp = &timeout;
2134: }
2135: for (;;) {
1.201 markus 2136: if (state->packet_timeout_ms != -1) {
1.154 dtucker 2137: ms_to_timeval(&timeout, ms_remain);
2138: gettimeofday(&start, NULL);
2139: }
1.201 markus 2140: if ((ret = select(state->connection_out + 1,
1.161 andreas 2141: NULL, setp, NULL, timeoutp)) >= 0)
1.154 dtucker 2142: break;
1.161 andreas 2143: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 2144: break;
1.201 markus 2145: if (state->packet_timeout_ms == -1)
1.154 dtucker 2146: continue;
2147: ms_subtract_diff(&start, &ms_remain);
2148: if (ms_remain <= 0) {
2149: ret = 0;
2150: break;
2151: }
2152: }
2153: if (ret == 0) {
1.205 djm 2154: free(setp);
2155: return SSH_ERR_CONN_TIMEOUT;
2156: }
2157: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2158: free(setp);
2159: return r;
1.154 dtucker 2160: }
1.14 markus 2161: }
1.186 djm 2162: free(setp);
1.205 djm 2163: return 0;
1.1 deraadt 2164: }
2165:
2166: /* Returns true if there is buffered data to write to the connection. */
2167:
1.2 provos 2168: int
1.201 markus 2169: ssh_packet_have_data_to_write(struct ssh *ssh)
1.1 deraadt 2170: {
1.201 markus 2171: return sshbuf_len(ssh->state->output) != 0;
1.1 deraadt 2172: }
2173:
2174: /* Returns true if there is not too much data to write to the connection. */
2175:
1.2 provos 2176: int
1.201 markus 2177: ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1.1 deraadt 2178: {
1.201 markus 2179: if (ssh->state->interactive_mode)
2180: return sshbuf_len(ssh->state->output) < 16384;
1.14 markus 2181: else
1.201 markus 2182: return sshbuf_len(ssh->state->output) < 128 * 1024;
1.1 deraadt 2183: }
2184:
1.201 markus 2185: void
2186: ssh_packet_set_tos(struct ssh *ssh, int tos)
1.101 markus 2187: {
1.201 markus 2188: if (!ssh_packet_connection_is_on_socket(ssh))
1.101 markus 2189: return;
1.201 markus 2190: switch (ssh_packet_connection_af(ssh)) {
1.173 djm 2191: case AF_INET:
2192: debug3("%s: set IP_TOS 0x%02x", __func__, tos);
1.201 markus 2193: if (setsockopt(ssh->state->connection_in,
1.173 djm 2194: IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2195: error("setsockopt IP_TOS %d: %.100s:",
2196: tos, strerror(errno));
2197: break;
2198: case AF_INET6:
2199: debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
1.201 markus 2200: if (setsockopt(ssh->state->connection_in,
1.173 djm 2201: IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2202: error("setsockopt IPV6_TCLASS %d: %.100s:",
2203: tos, strerror(errno));
2204: break;
2205: }
1.101 markus 2206: }
2207:
1.1 deraadt 2208: /* Informs that the current session is interactive. Sets IP flags for that. */
2209:
1.2 provos 2210: void
1.201 markus 2211: ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
1.1 deraadt 2212: {
1.201 markus 2213: struct session_state *state = ssh->state;
2214:
2215: if (state->set_interactive_called)
1.43 markus 2216: return;
1.201 markus 2217: state->set_interactive_called = 1;
1.1 deraadt 2218:
1.14 markus 2219: /* Record that we are in interactive mode. */
1.201 markus 2220: state->interactive_mode = interactive;
1.1 deraadt 2221:
1.19 markus 2222: /* Only set socket options if using a socket. */
1.201 markus 2223: if (!ssh_packet_connection_is_on_socket(ssh))
1.14 markus 2224: return;
1.201 markus 2225: set_nodelay(state->connection_in);
2226: ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2227: qos_bulk);
1.1 deraadt 2228: }
2229:
2230: /* Returns true if the current connection is interactive. */
2231:
1.2 provos 2232: int
1.201 markus 2233: ssh_packet_is_interactive(struct ssh *ssh)
1.1 deraadt 2234: {
1.201 markus 2235: return ssh->state->interactive_mode;
1.12 markus 2236: }
2237:
1.113 deraadt 2238: int
1.201 markus 2239: ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
1.12 markus 2240: {
1.201 markus 2241: struct session_state *state = ssh->state;
2242:
2243: if (state->set_maxsize_called) {
1.106 itojun 2244: logit("packet_set_maxsize: called twice: old %d new %d",
1.201 markus 2245: state->max_packet_size, s);
1.14 markus 2246: return -1;
2247: }
2248: if (s < 4 * 1024 || s > 1024 * 1024) {
1.106 itojun 2249: logit("packet_set_maxsize: bad size %d", s);
1.14 markus 2250: return -1;
2251: }
1.201 markus 2252: state->set_maxsize_called = 1;
1.66 markus 2253: debug("packet_set_maxsize: setting to %d", s);
1.201 markus 2254: state->max_packet_size = s;
1.14 markus 2255: return s;
1.53 markus 2256: }
2257:
1.161 andreas 2258: int
1.201 markus 2259: ssh_packet_inc_alive_timeouts(struct ssh *ssh)
1.161 andreas 2260: {
1.201 markus 2261: return ++ssh->state->keep_alive_timeouts;
1.161 andreas 2262: }
2263:
2264: void
1.201 markus 2265: ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
1.161 andreas 2266: {
1.201 markus 2267: ssh->state->keep_alive_timeouts = ka;
1.161 andreas 2268: }
2269:
2270: u_int
1.201 markus 2271: ssh_packet_get_maxsize(struct ssh *ssh)
1.71 markus 2272: {
1.201 markus 2273: return ssh->state->max_packet_size;
1.71 markus 2274: }
2275:
1.53 markus 2276: /*
2277: * 9.2. Ignored Data Message
1.61 markus 2278: *
1.53 markus 2279: * byte SSH_MSG_IGNORE
2280: * string data
1.61 markus 2281: *
1.53 markus 2282: * All implementations MUST understand (and ignore) this message at any
2283: * time (after receiving the protocol version). No implementation is
2284: * required to send them. This message can be used as an additional
2285: * protection measure against advanced traffic analysis techniques.
2286: */
1.54 markus 2287: void
1.201 markus 2288: ssh_packet_send_ignore(struct ssh *ssh, int nbytes)
1.54 markus 2289: {
1.115 avsm 2290: u_int32_t rnd = 0;
1.201 markus 2291: int r, i;
1.54 markus 2292:
1.201 markus 2293: if ((r = sshpkt_start(ssh, compat20 ?
2294: SSH2_MSG_IGNORE : SSH_MSG_IGNORE)) != 0 ||
2295: (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2296: fatal("%s: %s", __func__, ssh_err(r));
1.75 deraadt 2297: for (i = 0; i < nbytes; i++) {
1.53 markus 2298: if (i % 4 == 0)
1.115 avsm 2299: rnd = arc4random();
1.201 markus 2300: if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2301: fatal("%s: %s", __func__, ssh_err(r));
1.115 avsm 2302: rnd >>= 8;
1.53 markus 2303: }
1.105 markus 2304: }
2305:
2306: void
1.224 dtucker 2307: ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, time_t seconds)
1.105 markus 2308: {
1.224 dtucker 2309: debug3("rekey after %llu bytes, %d seconds", (unsigned long long)bytes,
1.184 dtucker 2310: (int)seconds);
1.201 markus 2311: ssh->state->rekey_limit = bytes;
2312: ssh->state->rekey_interval = seconds;
1.184 dtucker 2313: }
2314:
2315: time_t
1.201 markus 2316: ssh_packet_get_rekey_timeout(struct ssh *ssh)
1.184 dtucker 2317: {
2318: time_t seconds;
2319:
1.201 markus 2320: seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
1.187 dtucker 2321: monotime();
1.185 dtucker 2322: return (seconds <= 0 ? 1 : seconds);
1.118 markus 2323: }
2324:
2325: void
1.201 markus 2326: ssh_packet_set_server(struct ssh *ssh)
1.118 markus 2327: {
1.201 markus 2328: ssh->state->server_side = 1;
1.118 markus 2329: }
2330:
2331: void
1.201 markus 2332: ssh_packet_set_authenticated(struct ssh *ssh)
1.118 markus 2333: {
1.201 markus 2334: ssh->state->after_authentication = 1;
1.161 andreas 2335: }
2336:
2337: void *
1.201 markus 2338: ssh_packet_get_input(struct ssh *ssh)
1.161 andreas 2339: {
1.201 markus 2340: return (void *)ssh->state->input;
1.161 andreas 2341: }
2342:
2343: void *
1.201 markus 2344: ssh_packet_get_output(struct ssh *ssh)
1.161 andreas 2345: {
1.201 markus 2346: return (void *)ssh->state->output;
1.166 andreas 2347: }
2348:
1.196 markus 2349: /* Reset after_authentication and reset compression in post-auth privsep */
1.201 markus 2350: static int
2351: ssh_packet_set_postauth(struct ssh *ssh)
1.196 markus 2352: {
1.239 ! djm 2353: int r;
1.196 markus 2354:
2355: debug("%s: called", __func__);
2356: /* This was set in net child, but is not visible in user child */
1.201 markus 2357: ssh->state->after_authentication = 1;
2358: ssh->state->rekeying = 0;
1.239 ! djm 2359: if ((r = ssh_packet_enable_delayed_compress(ssh)) != 0)
! 2360: return r;
1.201 markus 2361: return 0;
2362: }
2363:
2364: /* Packet state (de-)serialization for privsep */
2365:
2366: /* turn kex into a blob for packet state serialization */
2367: static int
2368: kex_to_blob(struct sshbuf *m, struct kex *kex)
2369: {
2370: int r;
2371:
2372: if ((r = sshbuf_put_string(m, kex->session_id,
2373: kex->session_id_len)) != 0 ||
2374: (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2375: (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2376: (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2377: (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2378: (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2379: (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2380: (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2381: (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2382: return r;
2383: return 0;
2384: }
2385:
2386: /* turn key exchange results into a blob for packet state serialization */
2387: static int
2388: newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2389: {
2390: struct sshbuf *b;
2391: struct sshcipher_ctx *cc;
2392: struct sshcomp *comp;
2393: struct sshenc *enc;
2394: struct sshmac *mac;
2395: struct newkeys *newkey;
2396: int r;
2397:
2398: if ((newkey = ssh->state->newkeys[mode]) == NULL)
2399: return SSH_ERR_INTERNAL_ERROR;
2400: enc = &newkey->enc;
2401: mac = &newkey->mac;
2402: comp = &newkey->comp;
1.235 djm 2403: cc = (mode == MODE_OUT) ? ssh->state->send_context :
2404: ssh->state->receive_context;
1.201 markus 2405: if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2406: return r;
2407: if ((b = sshbuf_new()) == NULL)
2408: return SSH_ERR_ALLOC_FAIL;
2409: /* The cipher struct is constant and shared, you export pointer */
2410: if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2411: (r = sshbuf_put(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2412: (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2413: (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2414: (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2415: (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2416: goto out;
2417: if (cipher_authlen(enc->cipher) == 0) {
2418: if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2419: (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2420: (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2421: goto out;
2422: }
2423: if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2424: (r = sshbuf_put_cstring(b, comp->name)) != 0)
2425: goto out;
2426: r = sshbuf_put_stringb(m, b);
2427: out:
1.221 mmcc 2428: sshbuf_free(b);
1.201 markus 2429: return r;
2430: }
2431:
2432: /* serialize packet state into a blob */
2433: int
2434: ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2435: {
2436: struct session_state *state = ssh->state;
2437: u_char *p;
2438: size_t slen, rlen;
2439: int r, ssh1cipher;
2440:
2441: if (!compat20) {
1.235 djm 2442: ssh1cipher = cipher_ctx_get_number(state->receive_context);
2443: slen = cipher_get_keyiv_len(state->send_context);
2444: rlen = cipher_get_keyiv_len(state->receive_context);
1.201 markus 2445: if ((r = sshbuf_put_u32(m, state->remote_protocol_flags)) != 0 ||
2446: (r = sshbuf_put_u32(m, ssh1cipher)) != 0 ||
2447: (r = sshbuf_put_string(m, state->ssh1_key, state->ssh1_keylen)) != 0 ||
2448: (r = sshbuf_put_u32(m, slen)) != 0 ||
2449: (r = sshbuf_reserve(m, slen, &p)) != 0 ||
1.235 djm 2450: (r = cipher_get_keyiv(state->send_context, p, slen)) != 0 ||
1.201 markus 2451: (r = sshbuf_put_u32(m, rlen)) != 0 ||
2452: (r = sshbuf_reserve(m, rlen, &p)) != 0 ||
1.235 djm 2453: (r = cipher_get_keyiv(state->receive_context, p, rlen)) != 0)
1.201 markus 2454: return r;
2455: } else {
2456: if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2457: (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2458: (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
1.224 dtucker 2459: (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
1.208 markus 2460: (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
1.201 markus 2461: (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2462: (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2463: (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2464: (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2465: (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2466: (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2467: (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
2468: (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0)
2469: return r;
2470: }
2471:
1.235 djm 2472: slen = cipher_get_keycontext(state->send_context, NULL);
2473: rlen = cipher_get_keycontext(state->receive_context, NULL);
1.201 markus 2474: if ((r = sshbuf_put_u32(m, slen)) != 0 ||
2475: (r = sshbuf_reserve(m, slen, &p)) != 0)
2476: return r;
1.235 djm 2477: if (cipher_get_keycontext(state->send_context, p) != (int)slen)
1.201 markus 2478: return SSH_ERR_INTERNAL_ERROR;
2479: if ((r = sshbuf_put_u32(m, rlen)) != 0 ||
2480: (r = sshbuf_reserve(m, rlen, &p)) != 0)
2481: return r;
1.235 djm 2482: if (cipher_get_keycontext(state->receive_context, p) != (int)rlen)
1.201 markus 2483: return SSH_ERR_INTERNAL_ERROR;
1.239 ! djm 2484: if ((r = sshbuf_put_stringb(m, state->input)) != 0 ||
1.201 markus 2485: (r = sshbuf_put_stringb(m, state->output)) != 0)
2486: return r;
2487:
2488: return 0;
2489: }
2490:
2491: /* restore key exchange results from blob for packet state de-serialization */
2492: static int
2493: newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2494: {
2495: struct sshbuf *b = NULL;
2496: struct sshcomp *comp;
2497: struct sshenc *enc;
2498: struct sshmac *mac;
2499: struct newkeys *newkey = NULL;
2500: size_t keylen, ivlen, maclen;
2501: int r;
2502:
2503: if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2504: r = SSH_ERR_ALLOC_FAIL;
2505: goto out;
2506: }
2507: if ((r = sshbuf_froms(m, &b)) != 0)
2508: goto out;
2509: #ifdef DEBUG_PK
2510: sshbuf_dump(b, stderr);
2511: #endif
2512: enc = &newkey->enc;
2513: mac = &newkey->mac;
2514: comp = &newkey->comp;
2515:
2516: if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2517: (r = sshbuf_get(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2518: (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2519: (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2520: (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2521: (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2522: goto out;
2523: if (cipher_authlen(enc->cipher) == 0) {
2524: if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2525: goto out;
2526: if ((r = mac_setup(mac, mac->name)) != 0)
2527: goto out;
2528: if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2529: (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2530: goto out;
2531: if (maclen > mac->key_len) {
2532: r = SSH_ERR_INVALID_FORMAT;
2533: goto out;
2534: }
2535: mac->key_len = maclen;
2536: }
2537: if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2538: (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2539: goto out;
2540: if (enc->name == NULL ||
2541: cipher_by_name(enc->name) != enc->cipher) {
2542: r = SSH_ERR_INVALID_FORMAT;
2543: goto out;
2544: }
2545: if (sshbuf_len(b) != 0) {
2546: r = SSH_ERR_INVALID_FORMAT;
2547: goto out;
2548: }
2549: enc->key_len = keylen;
2550: enc->iv_len = ivlen;
2551: ssh->kex->newkeys[mode] = newkey;
2552: newkey = NULL;
2553: r = 0;
2554: out:
1.219 mmcc 2555: free(newkey);
1.221 mmcc 2556: sshbuf_free(b);
1.201 markus 2557: return r;
2558: }
2559:
2560: /* restore kex from blob for packet state de-serialization */
2561: static int
2562: kex_from_blob(struct sshbuf *m, struct kex **kexp)
2563: {
2564: struct kex *kex;
2565: int r;
2566:
2567: if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2568: (kex->my = sshbuf_new()) == NULL ||
2569: (kex->peer = sshbuf_new()) == NULL) {
2570: r = SSH_ERR_ALLOC_FAIL;
2571: goto out;
2572: }
2573: if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2574: (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2575: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2576: (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2577: (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2578: (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2579: (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2580: (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2581: (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2582: goto out;
2583: kex->server = 1;
2584: kex->done = 1;
2585: r = 0;
2586: out:
2587: if (r != 0 || kexp == NULL) {
2588: if (kex != NULL) {
1.221 mmcc 2589: sshbuf_free(kex->my);
2590: sshbuf_free(kex->peer);
1.201 markus 2591: free(kex);
2592: }
2593: if (kexp != NULL)
2594: *kexp = NULL;
2595: } else {
2596: *kexp = kex;
2597: }
2598: return r;
2599: }
2600:
2601: /*
2602: * Restore packet state from content of blob 'm' (de-serialization).
2603: * Note that 'm' will be partially consumed on parsing or any other errors.
2604: */
2605: int
2606: ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2607: {
2608: struct session_state *state = ssh->state;
2609: const u_char *ssh1key, *ivin, *ivout, *keyin, *keyout, *input, *output;
2610: size_t ssh1keylen, rlen, slen, ilen, olen;
2611: int r;
2612: u_int ssh1cipher = 0;
2613:
2614: if (!compat20) {
2615: if ((r = sshbuf_get_u32(m, &state->remote_protocol_flags)) != 0 ||
2616: (r = sshbuf_get_u32(m, &ssh1cipher)) != 0 ||
2617: (r = sshbuf_get_string_direct(m, &ssh1key, &ssh1keylen)) != 0 ||
2618: (r = sshbuf_get_string_direct(m, &ivout, &slen)) != 0 ||
2619: (r = sshbuf_get_string_direct(m, &ivin, &rlen)) != 0)
2620: return r;
2621: if (ssh1cipher > INT_MAX)
2622: return SSH_ERR_KEY_UNKNOWN_CIPHER;
2623: ssh_packet_set_encryption_key(ssh, ssh1key, ssh1keylen,
2624: (int)ssh1cipher);
1.235 djm 2625: if (cipher_get_keyiv_len(state->send_context) != (int)slen ||
2626: cipher_get_keyiv_len(state->receive_context) != (int)rlen)
1.201 markus 2627: return SSH_ERR_INVALID_FORMAT;
1.235 djm 2628: if ((r = cipher_set_keyiv(state->send_context, ivout)) != 0 ||
2629: (r = cipher_set_keyiv(state->receive_context, ivin)) != 0)
1.201 markus 2630: return r;
2631: } else {
2632: if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2633: (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2634: (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
1.224 dtucker 2635: (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
1.208 markus 2636: (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
1.201 markus 2637: (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2638: (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2639: (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2640: (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2641: (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2642: (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2643: (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2644: (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2645: return r;
1.208 markus 2646: /*
2647: * We set the time here so that in post-auth privsep slave we
2648: * count from the completion of the authentication.
2649: */
2650: state->rekey_time = monotime();
1.201 markus 2651: /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2652: if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2653: (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2654: return r;
2655: }
2656: if ((r = sshbuf_get_string_direct(m, &keyout, &slen)) != 0 ||
2657: (r = sshbuf_get_string_direct(m, &keyin, &rlen)) != 0)
2658: return r;
1.235 djm 2659: if (cipher_get_keycontext(state->send_context, NULL) != (int)slen ||
2660: cipher_get_keycontext(state->receive_context, NULL) != (int)rlen)
1.201 markus 2661: return SSH_ERR_INVALID_FORMAT;
1.235 djm 2662: cipher_set_keycontext(state->send_context, keyout);
2663: cipher_set_keycontext(state->receive_context, keyin);
1.201 markus 2664:
1.239 ! djm 2665: if ((r = ssh_packet_set_postauth(ssh)) != 0)
1.201 markus 2666: return r;
2667:
2668: sshbuf_reset(state->input);
2669: sshbuf_reset(state->output);
2670: if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2671: (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2672: (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2673: (r = sshbuf_put(state->output, output, olen)) != 0)
2674: return r;
2675:
2676: if (sshbuf_len(m))
2677: return SSH_ERR_INVALID_FORMAT;
2678: debug3("%s: done", __func__);
2679: return 0;
2680: }
2681:
2682: /* NEW API */
2683:
2684: /* put data to the outgoing packet */
2685:
2686: int
2687: sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2688: {
2689: return sshbuf_put(ssh->state->outgoing_packet, v, len);
2690: }
2691:
2692: int
2693: sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2694: {
2695: return sshbuf_putb(ssh->state->outgoing_packet, b);
2696: }
2697:
2698: int
2699: sshpkt_put_u8(struct ssh *ssh, u_char val)
2700: {
2701: return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2702: }
2703:
2704: int
2705: sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2706: {
2707: return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2708: }
2709:
2710: int
2711: sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2712: {
2713: return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2714: }
2715:
2716: int
2717: sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2718: {
2719: return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2720: }
2721:
2722: int
2723: sshpkt_put_cstring(struct ssh *ssh, const void *v)
2724: {
2725: return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2726: }
2727:
2728: int
2729: sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2730: {
2731: return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2732: }
2733:
1.211 djm 2734: #ifdef WITH_OPENSSL
1.201 markus 2735: int
2736: sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2737: {
2738: return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2739: }
2740:
1.211 djm 2741: #ifdef WITH_SSH1
1.201 markus 2742: int
2743: sshpkt_put_bignum1(struct ssh *ssh, const BIGNUM *v)
2744: {
2745: return sshbuf_put_bignum1(ssh->state->outgoing_packet, v);
2746: }
1.211 djm 2747: #endif /* WITH_SSH1 */
1.201 markus 2748:
2749: int
2750: sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2751: {
2752: return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2753: }
1.211 djm 2754: #endif /* WITH_OPENSSL */
1.201 markus 2755:
2756: /* fetch data from the incoming packet */
2757:
2758: int
2759: sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2760: {
2761: return sshbuf_get(ssh->state->incoming_packet, valp, len);
2762: }
2763:
2764: int
2765: sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2766: {
2767: return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2768: }
2769:
2770: int
2771: sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2772: {
2773: return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2774: }
2775:
2776: int
2777: sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2778: {
2779: return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2780: }
2781:
2782: int
2783: sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2784: {
2785: return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2786: }
2787:
2788: int
2789: sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2790: {
2791: return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2792: }
2793:
2794: int
2795: sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2796: {
2797: return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2798: }
2799:
1.211 djm 2800: #ifdef WITH_OPENSSL
1.201 markus 2801: int
2802: sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2803: {
2804: return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2805: }
2806:
1.211 djm 2807: #ifdef WITH_SSH1
1.201 markus 2808: int
2809: sshpkt_get_bignum1(struct ssh *ssh, BIGNUM *v)
2810: {
2811: return sshbuf_get_bignum1(ssh->state->incoming_packet, v);
2812: }
1.211 djm 2813: #endif /* WITH_SSH1 */
1.201 markus 2814:
2815: int
2816: sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2817: {
2818: return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2819: }
1.211 djm 2820: #endif /* WITH_OPENSSL */
1.201 markus 2821:
2822: int
2823: sshpkt_get_end(struct ssh *ssh)
2824: {
2825: if (sshbuf_len(ssh->state->incoming_packet) > 0)
2826: return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2827: return 0;
2828: }
2829:
2830: const u_char *
2831: sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2832: {
2833: if (lenp != NULL)
2834: *lenp = sshbuf_len(ssh->state->incoming_packet);
2835: return sshbuf_ptr(ssh->state->incoming_packet);
2836: }
2837:
2838: /* start a new packet */
2839:
2840: int
2841: sshpkt_start(struct ssh *ssh, u_char type)
2842: {
2843: u_char buf[9];
2844: int len;
2845:
2846: DBG(debug("packet_start[%d]", type));
2847: len = compat20 ? 6 : 9;
2848: memset(buf, 0, len - 1);
2849: buf[len - 1] = type;
2850: sshbuf_reset(ssh->state->outgoing_packet);
2851: return sshbuf_put(ssh->state->outgoing_packet, buf, len);
2852: }
2853:
2854: /* send it */
2855:
2856: int
2857: sshpkt_send(struct ssh *ssh)
2858: {
2859: if (compat20)
2860: return ssh_packet_send2(ssh);
2861: else
2862: return ssh_packet_send1(ssh);
2863: }
2864:
2865: int
2866: sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2867: {
2868: char buf[1024];
2869: va_list args;
2870: int r;
2871:
2872: va_start(args, fmt);
2873: vsnprintf(buf, sizeof(buf), fmt, args);
2874: va_end(args);
2875:
2876: if (compat20) {
2877: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2878: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2879: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2880: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2881: (r = sshpkt_send(ssh)) != 0)
2882: return r;
2883: } else {
2884: if ((r = sshpkt_start(ssh, SSH_MSG_DISCONNECT)) != 0 ||
2885: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2886: (r = sshpkt_send(ssh)) != 0)
2887: return r;
1.166 andreas 2888: }
1.201 markus 2889: return 0;
2890: }
2891:
2892: /* roundup current message to pad bytes */
2893: int
2894: sshpkt_add_padding(struct ssh *ssh, u_char pad)
2895: {
2896: ssh->state->extra_pad = pad;
2897: return 0;
1.1 deraadt 2898: }
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