Annotation of src/usr.bin/ssh/packet.c, Revision 1.249
1.249 ! djm 1: /* $OpenBSD: packet.c,v 1.248 2017/04/30 23:10:43 djm Exp $ */
1.1 deraadt 2: /*
1.15 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.35 deraadt 6: * This file contains code implementing the packet protocol and communication
7: * with the other side. This same code is used both on client and server side.
1.29 markus 8: *
1.35 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
1.29 markus 14: *
1.25 markus 15: *
16: * SSH2 packet format added by Markus Friedl.
1.69 markus 17: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.25 markus 18: *
1.35 deraadt 19: * Redistribution and use in source and binary forms, with or without
20: * modification, are permitted provided that the following conditions
21: * are met:
22: * 1. Redistributions of source code must retain the above copyright
23: * notice, this list of conditions and the following disclaimer.
24: * 2. Redistributions in binary form must reproduce the above copyright
25: * notice, this list of conditions and the following disclaimer in the
26: * documentation and/or other materials provided with the distribution.
27: *
28: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
29: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
30: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
31: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
32: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
33: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
37: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.15 deraadt 38: */
1.1 deraadt 39:
1.142 deraadt 40: #include <sys/types.h>
1.105 markus 41: #include <sys/queue.h>
1.132 stevesk 42: #include <sys/socket.h>
1.138 stevesk 43: #include <sys/time.h>
1.132 stevesk 44: #include <netinet/in.h>
1.121 stevesk 45: #include <netinet/ip.h>
1.134 stevesk 46:
1.135 stevesk 47: #include <errno.h>
1.230 djm 48: #include <netdb.h>
1.134 stevesk 49: #include <stdarg.h>
1.141 stevesk 50: #include <stdio.h>
1.140 stevesk 51: #include <stdlib.h>
1.137 stevesk 52: #include <string.h>
1.136 stevesk 53: #include <unistd.h>
1.203 deraadt 54: #include <limits.h>
1.142 deraadt 55: #include <signal.h>
1.184 dtucker 56: #include <time.h>
1.1 deraadt 57:
1.201 markus 58: #include <zlib.h>
59:
60: #include "buffer.h" /* typedefs XXX */
61: #include "key.h" /* typedefs XXX */
62:
1.1 deraadt 63: #include "xmalloc.h"
64: #include "crc32.h"
1.9 dugsong 65: #include "deattack.h"
1.25 markus 66: #include "compat.h"
1.45 markus 67: #include "ssh1.h"
1.25 markus 68: #include "ssh2.h"
1.37 markus 69: #include "cipher.h"
1.201 markus 70: #include "sshkey.h"
1.25 markus 71: #include "kex.h"
1.200 markus 72: #include "digest.h"
1.50 markus 73: #include "mac.h"
1.46 markus 74: #include "log.h"
75: #include "canohost.h"
1.87 stevesk 76: #include "misc.h"
1.198 millert 77: #include "channels.h"
1.95 markus 78: #include "ssh.h"
1.201 markus 79: #include "packet.h"
1.197 djm 80: #include "ssherr.h"
1.201 markus 81: #include "sshbuf.h"
1.25 markus 82:
83: #ifdef PACKET_DEBUG
84: #define DBG(x) x
85: #else
86: #define DBG(x)
87: #endif
88:
1.159 markus 89: #define PACKET_MAX_SIZE (256 * 1024)
90:
1.161 andreas 91: struct packet_state {
92: u_int32_t seqnr;
93: u_int32_t packets;
94: u_int64_t blocks;
95: u_int64_t bytes;
96: };
97:
98: struct packet {
99: TAILQ_ENTRY(packet) next;
100: u_char type;
1.201 markus 101: struct sshbuf *payload;
1.161 andreas 102: };
103:
104: struct session_state {
105: /*
106: * This variable contains the file descriptors used for
107: * communicating with the other side. connection_in is used for
108: * reading; connection_out for writing. These can be the same
109: * descriptor, in which case it is assumed to be a socket.
110: */
111: int connection_in;
112: int connection_out;
113:
114: /* Protocol flags for the remote side. */
115: u_int remote_protocol_flags;
1.1 deraadt 116:
1.161 andreas 117: /* Encryption context for receiving data. Only used for decryption. */
1.235 djm 118: struct sshcipher_ctx *receive_context;
1.1 deraadt 119:
1.161 andreas 120: /* Encryption context for sending data. Only used for encryption. */
1.235 djm 121: struct sshcipher_ctx *send_context;
1.14 markus 122:
1.161 andreas 123: /* Buffer for raw input data from the socket. */
1.201 markus 124: struct sshbuf *input;
1.1 deraadt 125:
1.161 andreas 126: /* Buffer for raw output data going to the socket. */
1.201 markus 127: struct sshbuf *output;
1.1 deraadt 128:
1.161 andreas 129: /* Buffer for the partial outgoing packet being constructed. */
1.201 markus 130: struct sshbuf *outgoing_packet;
1.1 deraadt 131:
1.161 andreas 132: /* Buffer for the incoming packet currently being processed. */
1.201 markus 133: struct sshbuf *incoming_packet;
1.1 deraadt 134:
1.161 andreas 135: /* Scratch buffer for packet compression/decompression. */
1.201 markus 136: struct sshbuf *compression_buffer;
137:
138: /* Incoming/outgoing compression dictionaries */
139: z_stream compression_in_stream;
140: z_stream compression_out_stream;
141: int compression_in_started;
142: int compression_out_started;
143: int compression_in_failures;
144: int compression_out_failures;
1.1 deraadt 145:
1.161 andreas 146: /*
147: * Flag indicating whether packet compression/decompression is
148: * enabled.
149: */
150: int packet_compression;
1.1 deraadt 151:
1.161 andreas 152: /* default maximum packet size */
153: u_int max_packet_size;
1.1 deraadt 154:
1.161 andreas 155: /* Flag indicating whether this module has been initialized. */
156: int initialized;
1.12 markus 157:
1.161 andreas 158: /* Set to true if the connection is interactive. */
159: int interactive_mode;
1.1 deraadt 160:
1.161 andreas 161: /* Set to true if we are the server side. */
162: int server_side;
1.1 deraadt 163:
1.161 andreas 164: /* Set to true if we are authenticated. */
165: int after_authentication;
1.118 markus 166:
1.161 andreas 167: int keep_alive_timeouts;
1.118 markus 168:
1.161 andreas 169: /* The maximum time that we will wait to send or receive a packet */
170: int packet_timeout_ms;
1.151 dtucker 171:
1.161 andreas 172: /* Session key information for Encryption and MAC */
1.201 markus 173: struct newkeys *newkeys[MODE_MAX];
1.161 andreas 174: struct packet_state p_read, p_send;
1.154 dtucker 175:
1.184 dtucker 176: /* Volume-based rekeying */
1.224 dtucker 177: u_int64_t max_blocks_in, max_blocks_out, rekey_limit;
1.105 markus 178:
1.184 dtucker 179: /* Time-based rekeying */
1.208 markus 180: u_int32_t rekey_interval; /* how often in seconds */
1.184 dtucker 181: time_t rekey_time; /* time of last rekeying */
182:
1.161 andreas 183: /* Session key for protocol v1 */
184: u_char ssh1_key[SSH_SESSION_KEY_LENGTH];
185: u_int ssh1_keylen;
1.25 markus 186:
1.161 andreas 187: /* roundup current message to extra_pad bytes */
188: u_char extra_pad;
1.95 markus 189:
1.161 andreas 190: /* XXX discard incoming data after MAC error */
191: u_int packet_discard;
1.234 markus 192: size_t packet_discard_mac_already;
1.201 markus 193: struct sshmac *packet_discard_mac;
1.71 markus 194:
1.161 andreas 195: /* Used in packet_read_poll2() */
196: u_int packlen;
1.159 markus 197:
1.165 andreas 198: /* Used in packet_send2 */
199: int rekeying;
200:
1.242 markus 201: /* Used in ssh_packet_send_mux() */
202: int mux;
203:
1.165 andreas 204: /* Used in packet_set_interactive */
205: int set_interactive_called;
206:
207: /* Used in packet_set_maxsize */
208: int set_maxsize_called;
209:
1.201 markus 210: /* One-off warning about weak ciphers */
211: int cipher_warning_done;
212:
213: /* SSH1 CRC compensation attack detector */
214: struct deattack_ctx deattack;
215:
1.243 djm 216: /* Hook for fuzzing inbound packets */
217: ssh_packet_hook_fn *hook_in;
218: void *hook_in_ctx;
219:
1.161 andreas 220: TAILQ_HEAD(, packet) outgoing;
1.105 markus 221: };
1.161 andreas 222:
1.201 markus 223: struct ssh *
224: ssh_alloc_session_state(void)
1.161 andreas 225: {
1.201 markus 226: struct ssh *ssh = NULL;
227: struct session_state *state = NULL;
1.161 andreas 228:
1.201 markus 229: if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
230: (state = calloc(1, sizeof(*state))) == NULL ||
231: (state->input = sshbuf_new()) == NULL ||
232: (state->output = sshbuf_new()) == NULL ||
233: (state->outgoing_packet = sshbuf_new()) == NULL ||
234: (state->incoming_packet = sshbuf_new()) == NULL)
235: goto fail;
236: TAILQ_INIT(&state->outgoing);
1.202 markus 237: TAILQ_INIT(&ssh->private_keys);
238: TAILQ_INIT(&ssh->public_keys);
1.201 markus 239: state->connection_in = -1;
240: state->connection_out = -1;
241: state->max_packet_size = 32768;
242: state->packet_timeout_ms = -1;
243: state->p_send.packets = state->p_read.packets = 0;
244: state->initialized = 1;
245: /*
246: * ssh_packet_send2() needs to queue packets until
247: * we've done the initial key exchange.
248: */
249: state->rekeying = 1;
250: ssh->state = state;
251: return ssh;
252: fail:
253: if (state) {
254: sshbuf_free(state->input);
255: sshbuf_free(state->output);
256: sshbuf_free(state->incoming_packet);
257: sshbuf_free(state->outgoing_packet);
258: free(state);
259: }
260: free(ssh);
261: return NULL;
1.161 andreas 262: }
1.105 markus 263:
1.243 djm 264: void
265: ssh_packet_set_input_hook(struct ssh *ssh, ssh_packet_hook_fn *hook, void *ctx)
266: {
267: ssh->state->hook_in = hook;
268: ssh->state->hook_in_ctx = ctx;
269: }
270:
1.228 djm 271: /* Returns nonzero if rekeying is in progress */
272: int
273: ssh_packet_is_rekeying(struct ssh *ssh)
274: {
1.249 ! djm 275: return ssh->state->rekeying ||
! 276: (ssh->kex != NULL && ssh->kex->done == 0);
1.228 djm 277: }
278:
1.16 markus 279: /*
280: * Sets the descriptors used for communication. Disables encryption until
281: * packet_set_encryption_key is called.
282: */
1.201 markus 283: struct ssh *
284: ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
1.1 deraadt 285: {
1.201 markus 286: struct session_state *state;
287: const struct sshcipher *none = cipher_by_name("none");
1.197 djm 288: int r;
1.97 deraadt 289:
1.205 djm 290: if (none == NULL) {
291: error("%s: cannot load cipher 'none'", __func__);
292: return NULL;
293: }
1.201 markus 294: if (ssh == NULL)
295: ssh = ssh_alloc_session_state();
1.205 djm 296: if (ssh == NULL) {
297: error("%s: cound not allocate state", __func__);
298: return NULL;
299: }
1.201 markus 300: state = ssh->state;
301: state->connection_in = fd_in;
302: state->connection_out = fd_out;
303: if ((r = cipher_init(&state->send_context, none,
1.197 djm 304: (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
1.201 markus 305: (r = cipher_init(&state->receive_context, none,
1.205 djm 306: (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
307: error("%s: cipher_init failed: %s", __func__, ssh_err(r));
1.230 djm 308: free(ssh); /* XXX need ssh_free_session_state? */
1.205 djm 309: return NULL;
310: }
1.201 markus 311: state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
312: deattack_init(&state->deattack);
1.207 djm 313: /*
314: * Cache the IP address of the remote connection for use in error
315: * messages that might be generated after the connection has closed.
316: */
317: (void)ssh_remote_ipaddr(ssh);
1.201 markus 318: return ssh;
1.1 deraadt 319: }
320:
1.154 dtucker 321: void
1.201 markus 322: ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
1.154 dtucker 323: {
1.201 markus 324: struct session_state *state = ssh->state;
325:
1.174 djm 326: if (timeout <= 0 || count <= 0) {
1.201 markus 327: state->packet_timeout_ms = -1;
1.154 dtucker 328: return;
329: }
330: if ((INT_MAX / 1000) / count < timeout)
1.201 markus 331: state->packet_timeout_ms = INT_MAX;
1.154 dtucker 332: else
1.201 markus 333: state->packet_timeout_ms = timeout * count * 1000;
1.154 dtucker 334: }
335:
1.242 markus 336: void
337: ssh_packet_set_mux(struct ssh *ssh)
338: {
339: ssh->state->mux = 1;
340: ssh->state->rekeying = 0;
341: }
342:
343: int
344: ssh_packet_get_mux(struct ssh *ssh)
345: {
346: return ssh->state->mux;
347: }
348:
1.201 markus 349: int
1.245 djm 350: ssh_packet_set_log_preamble(struct ssh *ssh, const char *fmt, ...)
351: {
352: va_list args;
353: int r;
354:
355: free(ssh->log_preamble);
356: if (fmt == NULL)
357: ssh->log_preamble = NULL;
358: else {
359: va_start(args, fmt);
360: r = vasprintf(&ssh->log_preamble, fmt, args);
361: va_end(args);
362: if (r < 0 || ssh->log_preamble == NULL)
363: return SSH_ERR_ALLOC_FAIL;
364: }
365: return 0;
366: }
367:
368: int
1.201 markus 369: ssh_packet_stop_discard(struct ssh *ssh)
1.159 markus 370: {
1.201 markus 371: struct session_state *state = ssh->state;
372: int r;
373:
374: if (state->packet_discard_mac) {
1.159 markus 375: char buf[1024];
1.234 markus 376: size_t dlen = PACKET_MAX_SIZE;
1.201 markus 377:
1.234 markus 378: if (dlen > state->packet_discard_mac_already)
379: dlen -= state->packet_discard_mac_already;
1.159 markus 380: memset(buf, 'a', sizeof(buf));
1.234 markus 381: while (sshbuf_len(state->incoming_packet) < dlen)
1.201 markus 382: if ((r = sshbuf_put(state->incoming_packet, buf,
383: sizeof(buf))) != 0)
384: return r;
385: (void) mac_compute(state->packet_discard_mac,
386: state->p_read.seqnr,
1.234 markus 387: sshbuf_ptr(state->incoming_packet), dlen,
1.201 markus 388: NULL, 0);
1.159 markus 389: }
1.220 djm 390: logit("Finished discarding for %.200s port %d",
391: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.201 markus 392: return SSH_ERR_MAC_INVALID;
1.159 markus 393: }
394:
1.201 markus 395: static int
396: ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
1.234 markus 397: struct sshmac *mac, size_t mac_already, u_int discard)
1.159 markus 398: {
1.201 markus 399: struct session_state *state = ssh->state;
400: int r;
401:
402: if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
403: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
404: return r;
405: return SSH_ERR_MAC_INVALID;
406: }
1.234 markus 407: /*
408: * Record number of bytes over which the mac has already
409: * been computed in order to minimize timing attacks.
410: */
411: if (mac && mac->enabled) {
1.201 markus 412: state->packet_discard_mac = mac;
1.234 markus 413: state->packet_discard_mac_already = mac_already;
414: }
415: if (sshbuf_len(state->input) >= discard)
416: return ssh_packet_stop_discard(ssh);
1.201 markus 417: state->packet_discard = discard - sshbuf_len(state->input);
418: return 0;
1.159 markus 419: }
420:
1.19 markus 421: /* Returns 1 if remote host is connected via socket, 0 if not. */
422:
423: int
1.201 markus 424: ssh_packet_connection_is_on_socket(struct ssh *ssh)
1.19 markus 425: {
1.201 markus 426: struct session_state *state = ssh->state;
1.19 markus 427: struct sockaddr_storage from, to;
428: socklen_t fromlen, tolen;
429:
1.230 djm 430: if (state->connection_in == -1 || state->connection_out == -1)
431: return 0;
432:
1.19 markus 433: /* filedescriptors in and out are the same, so it's a socket */
1.201 markus 434: if (state->connection_in == state->connection_out)
1.19 markus 435: return 1;
436: fromlen = sizeof(from);
437: memset(&from, 0, sizeof(from));
1.201 markus 438: if (getpeername(state->connection_in, (struct sockaddr *)&from,
1.161 andreas 439: &fromlen) < 0)
1.19 markus 440: return 0;
441: tolen = sizeof(to);
442: memset(&to, 0, sizeof(to));
1.201 markus 443: if (getpeername(state->connection_out, (struct sockaddr *)&to,
1.161 andreas 444: &tolen) < 0)
1.19 markus 445: return 0;
446: if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
447: return 0;
448: if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
449: return 0;
450: return 1;
451: }
452:
1.91 markus 453: void
1.201 markus 454: ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
1.91 markus 455: {
1.201 markus 456: if (ibytes)
457: *ibytes = ssh->state->p_read.bytes;
458: if (obytes)
459: *obytes = ssh->state->p_send.bytes;
1.91 markus 460: }
1.125 deraadt 461:
1.91 markus 462: int
1.201 markus 463: ssh_packet_connection_af(struct ssh *ssh)
1.19 markus 464: {
465: struct sockaddr_storage to;
1.21 deraadt 466: socklen_t tolen = sizeof(to);
1.19 markus 467:
468: memset(&to, 0, sizeof(to));
1.201 markus 469: if (getsockname(ssh->state->connection_out, (struct sockaddr *)&to,
1.161 andreas 470: &tolen) < 0)
1.19 markus 471: return 0;
1.173 djm 472: return to.ss_family;
1.19 markus 473: }
474:
1.1 deraadt 475: /* Sets the connection into non-blocking mode. */
476:
1.2 provos 477: void
1.201 markus 478: ssh_packet_set_nonblocking(struct ssh *ssh)
1.1 deraadt 479: {
1.14 markus 480: /* Set the socket into non-blocking mode. */
1.201 markus 481: set_nonblock(ssh->state->connection_in);
1.14 markus 482:
1.201 markus 483: if (ssh->state->connection_out != ssh->state->connection_in)
484: set_nonblock(ssh->state->connection_out);
1.1 deraadt 485: }
486:
487: /* Returns the socket used for reading. */
488:
1.2 provos 489: int
1.201 markus 490: ssh_packet_get_connection_in(struct ssh *ssh)
1.1 deraadt 491: {
1.201 markus 492: return ssh->state->connection_in;
1.1 deraadt 493: }
494:
495: /* Returns the descriptor used for writing. */
496:
1.2 provos 497: int
1.201 markus 498: ssh_packet_get_connection_out(struct ssh *ssh)
1.1 deraadt 499: {
1.201 markus 500: return ssh->state->connection_out;
501: }
502:
503: /*
504: * Returns the IP-address of the remote host as a string. The returned
505: * string must not be freed.
506: */
507:
508: const char *
509: ssh_remote_ipaddr(struct ssh *ssh)
510: {
1.220 djm 511: const int sock = ssh->state->connection_in;
512:
1.201 markus 513: /* Check whether we have cached the ipaddr. */
1.220 djm 514: if (ssh->remote_ipaddr == NULL) {
515: if (ssh_packet_connection_is_on_socket(ssh)) {
516: ssh->remote_ipaddr = get_peer_ipaddr(sock);
1.230 djm 517: ssh->remote_port = get_peer_port(sock);
518: ssh->local_ipaddr = get_local_ipaddr(sock);
519: ssh->local_port = get_local_port(sock);
1.220 djm 520: } else {
521: ssh->remote_ipaddr = strdup("UNKNOWN");
1.230 djm 522: ssh->remote_port = 65535;
523: ssh->local_ipaddr = strdup("UNKNOWN");
524: ssh->local_port = 65535;
1.220 djm 525: }
526: }
1.201 markus 527: return ssh->remote_ipaddr;
1.1 deraadt 528: }
529:
1.220 djm 530: /* Returns the port number of the remote host. */
531:
532: int
533: ssh_remote_port(struct ssh *ssh)
534: {
535: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
536: return ssh->remote_port;
1.230 djm 537: }
538:
539: /*
540: * Returns the IP-address of the local host as a string. The returned
541: * string must not be freed.
542: */
543:
544: const char *
545: ssh_local_ipaddr(struct ssh *ssh)
546: {
547: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
548: return ssh->local_ipaddr;
549: }
550:
551: /* Returns the port number of the local host. */
552:
553: int
554: ssh_local_port(struct ssh *ssh)
555: {
556: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
557: return ssh->local_port;
1.220 djm 558: }
559:
1.1 deraadt 560: /* Closes the connection and clears and frees internal data structures. */
561:
1.2 provos 562: void
1.201 markus 563: ssh_packet_close(struct ssh *ssh)
1.1 deraadt 564: {
1.201 markus 565: struct session_state *state = ssh->state;
566: u_int mode;
567:
568: if (!state->initialized)
1.14 markus 569: return;
1.201 markus 570: state->initialized = 0;
571: if (state->connection_in == state->connection_out) {
572: shutdown(state->connection_out, SHUT_RDWR);
573: close(state->connection_out);
1.14 markus 574: } else {
1.201 markus 575: close(state->connection_in);
576: close(state->connection_out);
1.14 markus 577: }
1.201 markus 578: sshbuf_free(state->input);
579: sshbuf_free(state->output);
580: sshbuf_free(state->outgoing_packet);
581: sshbuf_free(state->incoming_packet);
582: for (mode = 0; mode < MODE_MAX; mode++)
583: kex_free_newkeys(state->newkeys[mode]);
584: if (state->compression_buffer) {
585: sshbuf_free(state->compression_buffer);
586: if (state->compression_out_started) {
587: z_streamp stream = &state->compression_out_stream;
588: debug("compress outgoing: "
589: "raw data %llu, compressed %llu, factor %.2f",
590: (unsigned long long)stream->total_in,
591: (unsigned long long)stream->total_out,
592: stream->total_in == 0 ? 0.0 :
593: (double) stream->total_out / stream->total_in);
594: if (state->compression_out_failures == 0)
595: deflateEnd(stream);
596: }
597: if (state->compression_in_started) {
598: z_streamp stream = &state->compression_out_stream;
599: debug("compress incoming: "
600: "raw data %llu, compressed %llu, factor %.2f",
601: (unsigned long long)stream->total_out,
602: (unsigned long long)stream->total_in,
603: stream->total_out == 0 ? 0.0 :
604: (double) stream->total_in / stream->total_out);
605: if (state->compression_in_failures == 0)
606: inflateEnd(stream);
607: }
1.14 markus 608: }
1.235 djm 609: cipher_free(state->send_context);
610: cipher_free(state->receive_context);
611: state->send_context = state->receive_context = NULL;
1.219 mmcc 612: free(ssh->remote_ipaddr);
613: ssh->remote_ipaddr = NULL;
1.201 markus 614: free(ssh->state);
615: ssh->state = NULL;
1.1 deraadt 616: }
617:
618: /* Sets remote side protocol flags. */
619:
1.2 provos 620: void
1.201 markus 621: ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
1.1 deraadt 622: {
1.201 markus 623: ssh->state->remote_protocol_flags = protocol_flags;
1.1 deraadt 624: }
625:
626: /* Returns the remote protocol flags set earlier by the above function. */
627:
1.40 markus 628: u_int
1.201 markus 629: ssh_packet_get_protocol_flags(struct ssh *ssh)
1.1 deraadt 630: {
1.201 markus 631: return ssh->state->remote_protocol_flags;
1.1 deraadt 632: }
633:
1.16 markus 634: /*
635: * Starts packet compression from the next packet on in both directions.
636: * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
637: */
1.1 deraadt 638:
1.201 markus 639: static int
640: ssh_packet_init_compression(struct ssh *ssh)
1.60 markus 641: {
1.201 markus 642: if (!ssh->state->compression_buffer &&
643: ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
644: return SSH_ERR_ALLOC_FAIL;
645: return 0;
1.60 markus 646: }
647:
1.201 markus 648: static int
649: start_compression_out(struct ssh *ssh, int level)
1.1 deraadt 650: {
1.201 markus 651: if (level < 1 || level > 9)
652: return SSH_ERR_INVALID_ARGUMENT;
653: debug("Enabling compression at level %d.", level);
654: if (ssh->state->compression_out_started == 1)
655: deflateEnd(&ssh->state->compression_out_stream);
656: switch (deflateInit(&ssh->state->compression_out_stream, level)) {
657: case Z_OK:
658: ssh->state->compression_out_started = 1;
659: break;
660: case Z_MEM_ERROR:
661: return SSH_ERR_ALLOC_FAIL;
662: default:
663: return SSH_ERR_INTERNAL_ERROR;
664: }
665: return 0;
1.1 deraadt 666: }
667:
1.201 markus 668: static int
669: start_compression_in(struct ssh *ssh)
670: {
671: if (ssh->state->compression_in_started == 1)
672: inflateEnd(&ssh->state->compression_in_stream);
673: switch (inflateInit(&ssh->state->compression_in_stream)) {
674: case Z_OK:
675: ssh->state->compression_in_started = 1;
676: break;
677: case Z_MEM_ERROR:
678: return SSH_ERR_ALLOC_FAIL;
679: default:
680: return SSH_ERR_INTERNAL_ERROR;
681: }
682: return 0;
683: }
1.95 markus 684:
1.201 markus 685: int
686: ssh_packet_start_compression(struct ssh *ssh, int level)
1.1 deraadt 687: {
1.197 djm 688: int r;
1.97 deraadt 689:
1.249 ! djm 690: if (ssh->state->packet_compression)
1.201 markus 691: return SSH_ERR_INTERNAL_ERROR;
692: ssh->state->packet_compression = 1;
693: if ((r = ssh_packet_init_compression(ssh)) != 0 ||
694: (r = start_compression_in(ssh)) != 0 ||
695: (r = start_compression_out(ssh, level)) != 0)
696: return r;
697: return 0;
1.95 markus 698: }
699:
1.201 markus 700: /* XXX remove need for separate compression buffer */
701: static int
702: compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.95 markus 703: {
1.201 markus 704: u_char buf[4096];
705: int r, status;
706:
707: if (ssh->state->compression_out_started != 1)
708: return SSH_ERR_INTERNAL_ERROR;
709:
710: /* This case is not handled below. */
711: if (sshbuf_len(in) == 0)
712: return 0;
713:
714: /* Input is the contents of the input buffer. */
715: if ((ssh->state->compression_out_stream.next_in =
716: sshbuf_mutable_ptr(in)) == NULL)
717: return SSH_ERR_INTERNAL_ERROR;
718: ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
719:
720: /* Loop compressing until deflate() returns with avail_out != 0. */
721: do {
722: /* Set up fixed-size output buffer. */
723: ssh->state->compression_out_stream.next_out = buf;
724: ssh->state->compression_out_stream.avail_out = sizeof(buf);
725:
726: /* Compress as much data into the buffer as possible. */
727: status = deflate(&ssh->state->compression_out_stream,
728: Z_PARTIAL_FLUSH);
729: switch (status) {
730: case Z_MEM_ERROR:
731: return SSH_ERR_ALLOC_FAIL;
732: case Z_OK:
733: /* Append compressed data to output_buffer. */
734: if ((r = sshbuf_put(out, buf, sizeof(buf) -
735: ssh->state->compression_out_stream.avail_out)) != 0)
736: return r;
737: break;
738: case Z_STREAM_ERROR:
739: default:
740: ssh->state->compression_out_failures++;
741: return SSH_ERR_INVALID_FORMAT;
742: }
743: } while (ssh->state->compression_out_stream.avail_out == 0);
744: return 0;
1.1 deraadt 745: }
746:
1.201 markus 747: static int
748: uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.1 deraadt 749: {
1.201 markus 750: u_char buf[4096];
751: int r, status;
1.1 deraadt 752:
1.201 markus 753: if (ssh->state->compression_in_started != 1)
754: return SSH_ERR_INTERNAL_ERROR;
1.25 markus 755:
1.201 markus 756: if ((ssh->state->compression_in_stream.next_in =
757: sshbuf_mutable_ptr(in)) == NULL)
758: return SSH_ERR_INTERNAL_ERROR;
759: ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
1.97 deraadt 760:
1.201 markus 761: for (;;) {
762: /* Set up fixed-size output buffer. */
763: ssh->state->compression_in_stream.next_out = buf;
764: ssh->state->compression_in_stream.avail_out = sizeof(buf);
765:
766: status = inflate(&ssh->state->compression_in_stream,
767: Z_PARTIAL_FLUSH);
768: switch (status) {
769: case Z_OK:
770: if ((r = sshbuf_put(out, buf, sizeof(buf) -
771: ssh->state->compression_in_stream.avail_out)) != 0)
772: return r;
773: break;
774: case Z_BUF_ERROR:
775: /*
776: * Comments in zlib.h say that we should keep calling
777: * inflate() until we get an error. This appears to
778: * be the error that we get.
779: */
780: return 0;
781: case Z_DATA_ERROR:
782: return SSH_ERR_INVALID_FORMAT;
783: case Z_MEM_ERROR:
784: return SSH_ERR_ALLOC_FAIL;
785: case Z_STREAM_ERROR:
786: default:
787: ssh->state->compression_in_failures++;
788: return SSH_ERR_INTERNAL_ERROR;
789: }
790: }
791: /* NOTREACHED */
1.1 deraadt 792: }
1.125 deraadt 793:
1.201 markus 794: /*
795: * Causes any further packets to be encrypted using the given key. The same
796: * key is used for both sending and reception. However, both directions are
797: * encrypted independently of each other.
798: */
1.125 deraadt 799:
1.2 provos 800: void
1.201 markus 801: ssh_packet_set_encryption_key(struct ssh *ssh, const u_char *key, u_int keylen, int number)
1.1 deraadt 802: {
1.211 djm 803: fatal("no SSH protocol 1 support");
1.170 djm 804: }
805:
1.201 markus 806: int
807: ssh_set_newkeys(struct ssh *ssh, int mode)
1.57 markus 808: {
1.201 markus 809: struct session_state *state = ssh->state;
810: struct sshenc *enc;
811: struct sshmac *mac;
812: struct sshcomp *comp;
1.235 djm 813: struct sshcipher_ctx **ccp;
1.236 markus 814: struct packet_state *ps;
1.105 markus 815: u_int64_t *max_blocks;
1.236 markus 816: const char *wmsg, *dir;
1.197 djm 817: int r, crypt_type;
1.57 markus 818:
1.100 markus 819: debug2("set_newkeys: mode %d", mode);
1.57 markus 820:
1.88 markus 821: if (mode == MODE_OUT) {
1.236 markus 822: dir = "output";
1.235 djm 823: ccp = &state->send_context;
1.115 avsm 824: crypt_type = CIPHER_ENCRYPT;
1.236 markus 825: ps = &state->p_send;
1.201 markus 826: max_blocks = &state->max_blocks_out;
1.88 markus 827: } else {
1.236 markus 828: dir = "input";
1.235 djm 829: ccp = &state->receive_context;
1.115 avsm 830: crypt_type = CIPHER_DECRYPT;
1.236 markus 831: ps = &state->p_read;
1.201 markus 832: max_blocks = &state->max_blocks_in;
1.88 markus 833: }
1.201 markus 834: if (state->newkeys[mode] != NULL) {
1.236 markus 835: debug("%s: rekeying after %llu %s blocks"
836: " (%llu bytes total)", __func__,
837: (unsigned long long)ps->blocks, dir,
838: (unsigned long long)ps->bytes);
1.235 djm 839: cipher_free(*ccp);
840: *ccp = NULL;
1.201 markus 841: enc = &state->newkeys[mode]->enc;
842: mac = &state->newkeys[mode]->mac;
843: comp = &state->newkeys[mode]->comp;
1.148 pvalchev 844: mac_clear(mac);
1.192 djm 845: explicit_bzero(enc->iv, enc->iv_len);
846: explicit_bzero(enc->key, enc->key_len);
847: explicit_bzero(mac->key, mac->key_len);
1.186 djm 848: free(enc->name);
849: free(enc->iv);
850: free(enc->key);
851: free(mac->name);
852: free(mac->key);
853: free(comp->name);
1.201 markus 854: free(state->newkeys[mode]);
1.57 markus 855: }
1.236 markus 856: /* note that both bytes and the seqnr are not reset */
857: ps->packets = ps->blocks = 0;
1.201 markus 858: /* move newkeys from kex to state */
859: if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
860: return SSH_ERR_INTERNAL_ERROR;
861: ssh->kex->newkeys[mode] = NULL;
862: enc = &state->newkeys[mode]->enc;
863: mac = &state->newkeys[mode]->mac;
864: comp = &state->newkeys[mode]->comp;
865: if (cipher_authlen(enc->cipher) == 0) {
866: if ((r = mac_init(mac)) != 0)
867: return r;
868: }
869: mac->enabled = 1;
1.57 markus 870: DBG(debug("cipher_init_context: %d", mode));
1.235 djm 871: if ((r = cipher_init(ccp, enc->cipher, enc->key, enc->key_len,
1.197 djm 872: enc->iv, enc->iv_len, crypt_type)) != 0)
1.201 markus 873: return r;
874: if (!state->cipher_warning_done &&
1.235 djm 875: (wmsg = cipher_warning_message(*ccp)) != NULL) {
1.201 markus 876: error("Warning: %s", wmsg);
877: state->cipher_warning_done = 1;
878: }
1.91 markus 879: /* Deleting the keys does not gain extra security */
1.192 djm 880: /* explicit_bzero(enc->iv, enc->block_size);
881: explicit_bzero(enc->key, enc->key_len);
882: explicit_bzero(mac->key, mac->key_len); */
1.241 djm 883: if ((comp->type == COMP_ZLIB ||
884: (comp->type == COMP_DELAYED &&
885: state->after_authentication)) && comp->enabled == 0) {
1.201 markus 886: if ((r = ssh_packet_init_compression(ssh)) < 0)
887: return r;
888: if (mode == MODE_OUT) {
889: if ((r = start_compression_out(ssh, 6)) != 0)
890: return r;
891: } else {
892: if ((r = start_compression_in(ssh)) != 0)
893: return r;
894: }
1.57 markus 895: comp->enabled = 1;
896: }
1.109 markus 897: /*
898: * The 2^(blocksize*2) limit is too expensive for 3DES,
899: * blowfish, etc, so enforce a 1GB limit for small blocksizes.
900: */
901: if (enc->block_size >= 16)
902: *max_blocks = (u_int64_t)1 << (enc->block_size*2);
903: else
904: *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1.201 markus 905: if (state->rekey_limit)
1.237 deraadt 906: *max_blocks = MINIMUM(*max_blocks,
1.201 markus 907: state->rekey_limit / enc->block_size);
1.227 djm 908: debug("rekey after %llu blocks", (unsigned long long)*max_blocks);
1.201 markus 909: return 0;
1.57 markus 910: }
911:
1.228 djm 912: #define MAX_PACKETS (1U<<31)
913: static int
914: ssh_packet_need_rekeying(struct ssh *ssh, u_int outbound_packet_len)
915: {
916: struct session_state *state = ssh->state;
917: u_int32_t out_blocks;
918:
919: /* XXX client can't cope with rekeying pre-auth */
920: if (!state->after_authentication)
921: return 0;
922:
923: /* Haven't keyed yet or KEX in progress. */
924: if (ssh->kex == NULL || ssh_packet_is_rekeying(ssh))
925: return 0;
926:
927: /* Peer can't rekey */
928: if (ssh->compat & SSH_BUG_NOREKEY)
929: return 0;
930:
931: /*
932: * Permit one packet in or out per rekey - this allows us to
933: * make progress when rekey limits are very small.
934: */
935: if (state->p_send.packets == 0 && state->p_read.packets == 0)
936: return 0;
937:
938: /* Time-based rekeying */
939: if (state->rekey_interval != 0 &&
1.244 dtucker 940: (int64_t)state->rekey_time + state->rekey_interval <= monotime())
1.228 djm 941: return 1;
942:
943: /* Always rekey when MAX_PACKETS sent in either direction */
944: if (state->p_send.packets > MAX_PACKETS ||
945: state->p_read.packets > MAX_PACKETS)
946: return 1;
947:
948: /* Rekey after (cipher-specific) maxiumum blocks */
1.237 deraadt 949: out_blocks = ROUNDUP(outbound_packet_len,
1.228 djm 950: state->newkeys[MODE_OUT]->enc.block_size);
951: return (state->max_blocks_out &&
952: (state->p_send.blocks + out_blocks > state->max_blocks_out)) ||
953: (state->max_blocks_in &&
954: (state->p_read.blocks > state->max_blocks_in));
955: }
956:
1.16 markus 957: /*
1.118 markus 958: * Delayed compression for SSH2 is enabled after authentication:
1.143 dtucker 959: * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1.118 markus 960: * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
961: */
1.201 markus 962: static int
963: ssh_packet_enable_delayed_compress(struct ssh *ssh)
1.118 markus 964: {
1.201 markus 965: struct session_state *state = ssh->state;
966: struct sshcomp *comp = NULL;
967: int r, mode;
1.118 markus 968:
969: /*
970: * Remember that we are past the authentication step, so rekeying
971: * with COMP_DELAYED will turn on compression immediately.
972: */
1.201 markus 973: state->after_authentication = 1;
1.118 markus 974: for (mode = 0; mode < MODE_MAX; mode++) {
1.145 markus 975: /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1.201 markus 976: if (state->newkeys[mode] == NULL)
1.145 markus 977: continue;
1.201 markus 978: comp = &state->newkeys[mode]->comp;
1.118 markus 979: if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1.201 markus 980: if ((r = ssh_packet_init_compression(ssh)) != 0)
981: return r;
982: if (mode == MODE_OUT) {
983: if ((r = start_compression_out(ssh, 6)) != 0)
984: return r;
985: } else {
986: if ((r = start_compression_in(ssh)) != 0)
987: return r;
988: }
1.118 markus 989: comp->enabled = 1;
990: }
991: }
1.201 markus 992: return 0;
1.118 markus 993: }
994:
1.226 djm 995: /* Used to mute debug logging for noisy packet types */
1.242 markus 996: int
1.226 djm 997: ssh_packet_log_type(u_char type)
998: {
999: switch (type) {
1000: case SSH2_MSG_CHANNEL_DATA:
1001: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1002: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1003: return 0;
1004: default:
1005: return 1;
1006: }
1007: }
1008:
1.118 markus 1009: /*
1.25 markus 1010: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1011: */
1.201 markus 1012: int
1013: ssh_packet_send2_wrapped(struct ssh *ssh)
1.25 markus 1014: {
1.201 markus 1015: struct session_state *state = ssh->state;
1.200 markus 1016: u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1.233 djm 1017: u_char tmp, padlen, pad = 0;
1.201 markus 1018: u_int authlen = 0, aadlen = 0;
1019: u_int len;
1020: struct sshenc *enc = NULL;
1021: struct sshmac *mac = NULL;
1022: struct sshcomp *comp = NULL;
1023: int r, block_size;
1024:
1025: if (state->newkeys[MODE_OUT] != NULL) {
1026: enc = &state->newkeys[MODE_OUT]->enc;
1027: mac = &state->newkeys[MODE_OUT]->mac;
1028: comp = &state->newkeys[MODE_OUT]->comp;
1.180 markus 1029: /* disable mac for authenticated encryption */
1030: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1031: mac = NULL;
1.25 markus 1032: }
1.88 markus 1033: block_size = enc ? enc->block_size : 8;
1.180 markus 1034: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1035:
1.201 markus 1036: type = (sshbuf_ptr(state->outgoing_packet))[5];
1.226 djm 1037: if (ssh_packet_log_type(type))
1038: debug3("send packet: type %u", type);
1.25 markus 1039: #ifdef PACKET_DEBUG
1040: fprintf(stderr, "plain: ");
1.201 markus 1041: sshbuf_dump(state->outgoing_packet, stderr);
1.25 markus 1042: #endif
1043:
1044: if (comp && comp->enabled) {
1.201 markus 1045: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1046: /* skip header, compress only payload */
1.201 markus 1047: if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1048: goto out;
1049: sshbuf_reset(state->compression_buffer);
1050: if ((r = compress_buffer(ssh, state->outgoing_packet,
1051: state->compression_buffer)) != 0)
1052: goto out;
1053: sshbuf_reset(state->outgoing_packet);
1054: if ((r = sshbuf_put(state->outgoing_packet,
1055: "\0\0\0\0\0", 5)) != 0 ||
1056: (r = sshbuf_putb(state->outgoing_packet,
1057: state->compression_buffer)) != 0)
1058: goto out;
1059: DBG(debug("compression: raw %d compressed %zd", len,
1060: sshbuf_len(state->outgoing_packet)));
1.25 markus 1061: }
1062:
1063: /* sizeof (packet_len + pad_len + payload) */
1.201 markus 1064: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1065:
1066: /*
1067: * calc size of padding, alloc space, get random data,
1068: * minimum padding is 4 bytes
1069: */
1.178 markus 1070: len -= aadlen; /* packet length is not encrypted for EtM modes */
1.25 markus 1071: padlen = block_size - (len % block_size);
1072: if (padlen < 4)
1073: padlen += block_size;
1.201 markus 1074: if (state->extra_pad) {
1.233 djm 1075: tmp = state->extra_pad;
1.201 markus 1076: state->extra_pad =
1.237 deraadt 1077: ROUNDUP(state->extra_pad, block_size);
1.233 djm 1078: /* check if roundup overflowed */
1079: if (state->extra_pad < tmp)
1080: return SSH_ERR_INVALID_ARGUMENT;
1081: tmp = (len + padlen) % state->extra_pad;
1082: /* Check whether pad calculation below will underflow */
1083: if (tmp > state->extra_pad)
1084: return SSH_ERR_INVALID_ARGUMENT;
1085: pad = state->extra_pad - tmp;
1.193 djm 1086: DBG(debug3("%s: adding %d (len %d padlen %d extra_pad %d)",
1.201 markus 1087: __func__, pad, len, padlen, state->extra_pad));
1.233 djm 1088: tmp = padlen;
1.71 markus 1089: padlen += pad;
1.233 djm 1090: /* Check whether padlen calculation overflowed */
1091: if (padlen < tmp)
1092: return SSH_ERR_INVALID_ARGUMENT; /* overflow */
1.201 markus 1093: state->extra_pad = 0;
1.71 markus 1094: }
1.201 markus 1095: if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1096: goto out;
1.235 djm 1097: if (enc && !cipher_ctx_is_plaintext(state->send_context)) {
1.32 markus 1098: /* random padding */
1.201 markus 1099: arc4random_buf(cp, padlen);
1.32 markus 1100: } else {
1101: /* clear padding */
1.192 djm 1102: explicit_bzero(cp, padlen);
1.25 markus 1103: }
1.178 markus 1104: /* sizeof (packet_len + pad_len + payload + padding) */
1.201 markus 1105: len = sshbuf_len(state->outgoing_packet);
1106: cp = sshbuf_mutable_ptr(state->outgoing_packet);
1107: if (cp == NULL) {
1108: r = SSH_ERR_INTERNAL_ERROR;
1109: goto out;
1110: }
1.25 markus 1111: /* packet_length includes payload, padding and padding length field */
1.201 markus 1112: POKE_U32(cp, len - 4);
1.89 markus 1113: cp[4] = padlen;
1.178 markus 1114: DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1115: len, padlen, aadlen));
1.25 markus 1116:
1117: /* compute MAC over seqnr and packet(length fields, payload, padding) */
1.178 markus 1118: if (mac && mac->enabled && !mac->etm) {
1.201 markus 1119: if ((r = mac_compute(mac, state->p_send.seqnr,
1120: sshbuf_ptr(state->outgoing_packet), len,
1.200 markus 1121: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1122: goto out;
1123: DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1.25 markus 1124: }
1125: /* encrypt packet and append to output buffer. */
1.201 markus 1126: if ((r = sshbuf_reserve(state->output,
1127: sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1128: goto out;
1.235 djm 1129: if ((r = cipher_crypt(state->send_context, state->p_send.seqnr, cp,
1.201 markus 1130: sshbuf_ptr(state->outgoing_packet),
1131: len - aadlen, aadlen, authlen)) != 0)
1132: goto out;
1.25 markus 1133: /* append unencrypted MAC */
1.178 markus 1134: if (mac && mac->enabled) {
1135: if (mac->etm) {
1136: /* EtM: compute mac over aadlen + cipher text */
1.201 markus 1137: if ((r = mac_compute(mac, state->p_send.seqnr,
1138: cp, len, macbuf, sizeof(macbuf))) != 0)
1139: goto out;
1.178 markus 1140: DBG(debug("done calc MAC(EtM) out #%d",
1.201 markus 1141: state->p_send.seqnr));
1.178 markus 1142: }
1.201 markus 1143: if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1144: goto out;
1.178 markus 1145: }
1.25 markus 1146: #ifdef PACKET_DEBUG
1147: fprintf(stderr, "encrypted: ");
1.201 markus 1148: sshbuf_dump(state->output, stderr);
1.25 markus 1149: #endif
1.29 markus 1150: /* increment sequence number for outgoing packets */
1.201 markus 1151: if (++state->p_send.seqnr == 0)
1.106 itojun 1152: logit("outgoing seqnr wraps around");
1.201 markus 1153: if (++state->p_send.packets == 0)
1154: if (!(ssh->compat & SSH_BUG_NOREKEY))
1155: return SSH_ERR_NEED_REKEY;
1156: state->p_send.blocks += len / block_size;
1157: state->p_send.bytes += len;
1158: sshbuf_reset(state->outgoing_packet);
1.25 markus 1159:
1.57 markus 1160: if (type == SSH2_MSG_NEWKEYS)
1.201 markus 1161: r = ssh_set_newkeys(ssh, MODE_OUT);
1162: else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1163: r = ssh_packet_enable_delayed_compress(ssh);
1164: else
1165: r = 0;
1166: out:
1167: return r;
1.25 markus 1168: }
1169:
1.228 djm 1170: /* returns non-zero if the specified packet type is usec by KEX */
1171: static int
1172: ssh_packet_type_is_kex(u_char type)
1173: {
1174: return
1175: type >= SSH2_MSG_TRANSPORT_MIN &&
1176: type <= SSH2_MSG_TRANSPORT_MAX &&
1177: type != SSH2_MSG_SERVICE_REQUEST &&
1178: type != SSH2_MSG_SERVICE_ACCEPT &&
1179: type != SSH2_MSG_EXT_INFO;
1180: }
1181:
1.201 markus 1182: int
1183: ssh_packet_send2(struct ssh *ssh)
1.105 markus 1184: {
1.201 markus 1185: struct session_state *state = ssh->state;
1.105 markus 1186: struct packet *p;
1.201 markus 1187: u_char type;
1.228 djm 1188: int r, need_rekey;
1.105 markus 1189:
1.228 djm 1190: if (sshbuf_len(state->outgoing_packet) < 6)
1191: return SSH_ERR_INTERNAL_ERROR;
1.201 markus 1192: type = sshbuf_ptr(state->outgoing_packet)[5];
1.228 djm 1193: need_rekey = !ssh_packet_type_is_kex(type) &&
1194: ssh_packet_need_rekeying(ssh, sshbuf_len(state->outgoing_packet));
1.105 markus 1195:
1.228 djm 1196: /*
1197: * During rekeying we can only send key exchange messages.
1198: * Queue everything else.
1199: */
1200: if ((need_rekey || state->rekeying) && !ssh_packet_type_is_kex(type)) {
1201: if (need_rekey)
1202: debug3("%s: rekex triggered", __func__);
1203: debug("enqueue packet: %u", type);
1204: p = calloc(1, sizeof(*p));
1205: if (p == NULL)
1206: return SSH_ERR_ALLOC_FAIL;
1207: p->type = type;
1208: p->payload = state->outgoing_packet;
1209: TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1210: state->outgoing_packet = sshbuf_new();
1211: if (state->outgoing_packet == NULL)
1212: return SSH_ERR_ALLOC_FAIL;
1213: if (need_rekey) {
1214: /*
1215: * This packet triggered a rekey, so send the
1216: * KEXINIT now.
1217: * NB. reenters this function via kex_start_rekex().
1218: */
1219: return kex_start_rekex(ssh);
1.105 markus 1220: }
1.228 djm 1221: return 0;
1.105 markus 1222: }
1223:
1224: /* rekeying starts with sending KEXINIT */
1225: if (type == SSH2_MSG_KEXINIT)
1.201 markus 1226: state->rekeying = 1;
1.105 markus 1227:
1.201 markus 1228: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1229: return r;
1.105 markus 1230:
1231: /* after a NEWKEYS message we can send the complete queue */
1232: if (type == SSH2_MSG_NEWKEYS) {
1.201 markus 1233: state->rekeying = 0;
1234: state->rekey_time = monotime();
1235: while ((p = TAILQ_FIRST(&state->outgoing))) {
1.105 markus 1236: type = p->type;
1.228 djm 1237: /*
1238: * If this packet triggers a rekex, then skip the
1239: * remaining packets in the queue for now.
1240: * NB. re-enters this function via kex_start_rekex.
1241: */
1242: if (ssh_packet_need_rekeying(ssh,
1243: sshbuf_len(p->payload))) {
1244: debug3("%s: queued packet triggered rekex",
1245: __func__);
1246: return kex_start_rekex(ssh);
1247: }
1.105 markus 1248: debug("dequeue packet: %u", type);
1.201 markus 1249: sshbuf_free(state->outgoing_packet);
1250: state->outgoing_packet = p->payload;
1251: TAILQ_REMOVE(&state->outgoing, p, next);
1.228 djm 1252: memset(p, 0, sizeof(*p));
1.186 djm 1253: free(p);
1.201 markus 1254: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1255: return r;
1.105 markus 1256: }
1257: }
1.201 markus 1258: return 0;
1.25 markus 1259: }
1260:
1261: /*
1.16 markus 1262: * Waits until a packet has been received, and returns its type. Note that
1263: * no other data is processed until this returns, so this function should not
1264: * be used during the interactive session.
1265: */
1.1 deraadt 1266:
1.2 provos 1267: int
1.201 markus 1268: ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.1 deraadt 1269: {
1.201 markus 1270: struct session_state *state = ssh->state;
1.222 markus 1271: int len, r, ms_remain;
1.56 millert 1272: fd_set *setp;
1.14 markus 1273: char buf[8192];
1.155 deraadt 1274: struct timeval timeout, start, *timeoutp = NULL;
1275:
1.25 markus 1276: DBG(debug("packet_read()"));
1.14 markus 1277:
1.214 deraadt 1278: setp = calloc(howmany(state->connection_in + 1,
1.161 andreas 1279: NFDBITS), sizeof(fd_mask));
1.201 markus 1280: if (setp == NULL)
1281: return SSH_ERR_ALLOC_FAIL;
1.56 millert 1282:
1.205 djm 1283: /*
1284: * Since we are blocking, ensure that all written packets have
1285: * been sent.
1286: */
1.210 markus 1287: if ((r = ssh_packet_write_wait(ssh)) != 0)
1288: goto out;
1.14 markus 1289:
1290: /* Stay in the loop until we have received a complete packet. */
1291: for (;;) {
1292: /* Try to read a packet from the buffer. */
1.201 markus 1293: r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p);
1294: if (r != 0)
1295: break;
1.14 markus 1296: /* If we got a packet, return it. */
1.201 markus 1297: if (*typep != SSH_MSG_NONE)
1298: break;
1.16 markus 1299: /*
1300: * Otherwise, wait for some data to arrive, add it to the
1301: * buffer, and try again.
1302: */
1.201 markus 1303: memset(setp, 0, howmany(state->connection_in + 1,
1.161 andreas 1304: NFDBITS) * sizeof(fd_mask));
1.201 markus 1305: FD_SET(state->connection_in, setp);
1.16 markus 1306:
1.201 markus 1307: if (state->packet_timeout_ms > 0) {
1308: ms_remain = state->packet_timeout_ms;
1.154 dtucker 1309: timeoutp = &timeout;
1310: }
1.14 markus 1311: /* Wait for some data to arrive. */
1.154 dtucker 1312: for (;;) {
1.201 markus 1313: if (state->packet_timeout_ms != -1) {
1.154 dtucker 1314: ms_to_timeval(&timeout, ms_remain);
1315: gettimeofday(&start, NULL);
1316: }
1.201 markus 1317: if ((r = select(state->connection_in + 1, setp,
1.161 andreas 1318: NULL, NULL, timeoutp)) >= 0)
1.154 dtucker 1319: break;
1.161 andreas 1320: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 1321: break;
1.201 markus 1322: if (state->packet_timeout_ms == -1)
1.154 dtucker 1323: continue;
1324: ms_subtract_diff(&start, &ms_remain);
1325: if (ms_remain <= 0) {
1.201 markus 1326: r = 0;
1.154 dtucker 1327: break;
1328: }
1329: }
1.246 djm 1330: if (r == 0) {
1331: r = SSH_ERR_CONN_TIMEOUT;
1332: goto out;
1333: }
1.14 markus 1334: /* Read data from the socket. */
1.222 markus 1335: len = read(state->connection_in, buf, sizeof(buf));
1.210 markus 1336: if (len == 0) {
1337: r = SSH_ERR_CONN_CLOSED;
1338: goto out;
1339: }
1340: if (len < 0) {
1341: r = SSH_ERR_SYSTEM_ERROR;
1342: goto out;
1343: }
1.204 djm 1344:
1.14 markus 1345: /* Append it to the buffer. */
1.204 djm 1346: if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1.210 markus 1347: goto out;
1.14 markus 1348: }
1.210 markus 1349: out:
1.201 markus 1350: free(setp);
1351: return r;
1.1 deraadt 1352: }
1353:
1.77 djm 1354: int
1.201 markus 1355: ssh_packet_read(struct ssh *ssh)
1.77 djm 1356: {
1.201 markus 1357: u_char type;
1358: int r;
1359:
1360: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1361: fatal("%s: %s", __func__, ssh_err(r));
1362: return type;
1.77 djm 1363: }
1364:
1.16 markus 1365: /*
1366: * Waits until a packet has been received, verifies that its type matches
1367: * that given, and gives a fatal error and exits if there is a mismatch.
1368: */
1.1 deraadt 1369:
1.205 djm 1370: int
1371: ssh_packet_read_expect(struct ssh *ssh, u_int expected_type)
1.1 deraadt 1372: {
1.205 djm 1373: int r;
1374: u_char type;
1.1 deraadt 1375:
1.205 djm 1376: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1377: return r;
1378: if (type != expected_type) {
1379: if ((r = sshpkt_disconnect(ssh,
1.201 markus 1380: "Protocol error: expected packet type %d, got %d",
1.205 djm 1381: expected_type, type)) != 0)
1382: return r;
1383: return SSH_ERR_PROTOCOL_ERROR;
1384: }
1385: return 0;
1.1 deraadt 1386: }
1387:
1388: /* Checks if a full packet is available in the data received so far via
1.14 markus 1389: * packet_process_incoming. If so, reads the packet; otherwise returns
1390: * SSH_MSG_NONE. This does not wait for data from the connection.
1391: *
1.150 dtucker 1392: * SSH_MSG_DISCONNECT is handled specially here. Also,
1393: * SSH_MSG_IGNORE messages are skipped by this function and are never returned
1394: * to higher levels.
1.14 markus 1395: */
1.1 deraadt 1396:
1.201 markus 1397: int
1398: ssh_packet_read_poll1(struct ssh *ssh, u_char *typep)
1.1 deraadt 1399: {
1.201 markus 1400: struct session_state *state = ssh->state;
1.40 markus 1401: u_int len, padded_len;
1.205 djm 1402: const char *emsg;
1.201 markus 1403: const u_char *cp;
1404: u_char *p;
1.40 markus 1405: u_int checksum, stored_checksum;
1.201 markus 1406: int r;
1407:
1408: *typep = SSH_MSG_NONE;
1.14 markus 1409:
1410: /* Check if input size is less than minimum packet size. */
1.201 markus 1411: if (sshbuf_len(state->input) < 4 + 8)
1412: return 0;
1.14 markus 1413: /* Get length of incoming packet. */
1.201 markus 1414: len = PEEK_U32(sshbuf_ptr(state->input));
1.205 djm 1415: if (len < 1 + 2 + 2 || len > 256 * 1024) {
1416: if ((r = sshpkt_disconnect(ssh, "Bad packet length %u",
1417: len)) != 0)
1418: return r;
1419: return SSH_ERR_CONN_CORRUPT;
1420: }
1.14 markus 1421: padded_len = (len + 8) & ~7;
1422:
1423: /* Check if the packet has been entirely received. */
1.201 markus 1424: if (sshbuf_len(state->input) < 4 + padded_len)
1425: return 0;
1.14 markus 1426:
1427: /* The entire packet is in buffer. */
1428:
1429: /* Consume packet length. */
1.201 markus 1430: if ((r = sshbuf_consume(state->input, 4)) != 0)
1431: goto out;
1.14 markus 1432:
1.62 markus 1433: /*
1434: * Cryptographic attack detector for ssh
1435: * (C)1998 CORE-SDI, Buenos Aires Argentina
1436: * Ariel Futoransky(futo@core-sdi.com)
1437: */
1.235 djm 1438: if (!cipher_ctx_is_plaintext(state->receive_context)) {
1.205 djm 1439: emsg = NULL;
1.201 markus 1440: switch (detect_attack(&state->deattack,
1441: sshbuf_ptr(state->input), padded_len)) {
1442: case DEATTACK_OK:
1443: break;
1.144 djm 1444: case DEATTACK_DETECTED:
1.205 djm 1445: emsg = "crc32 compensation attack detected";
1446: break;
1.144 djm 1447: case DEATTACK_DOS_DETECTED:
1.205 djm 1448: emsg = "deattack denial of service detected";
1449: break;
1.201 markus 1450: default:
1.205 djm 1451: emsg = "deattack error";
1452: break;
1453: }
1454: if (emsg != NULL) {
1455: error("%s", emsg);
1456: if ((r = sshpkt_disconnect(ssh, "%s", emsg)) != 0 ||
1457: (r = ssh_packet_write_wait(ssh)) != 0)
1458: return r;
1459: return SSH_ERR_CONN_CORRUPT;
1.144 djm 1460: }
1461: }
1.62 markus 1462:
1463: /* Decrypt data to incoming_packet. */
1.201 markus 1464: sshbuf_reset(state->incoming_packet);
1465: if ((r = sshbuf_reserve(state->incoming_packet, padded_len, &p)) != 0)
1466: goto out;
1.235 djm 1467: if ((r = cipher_crypt(state->receive_context, 0, p,
1.201 markus 1468: sshbuf_ptr(state->input), padded_len, 0, 0)) != 0)
1469: goto out;
1.62 markus 1470:
1.201 markus 1471: if ((r = sshbuf_consume(state->input, padded_len)) != 0)
1472: goto out;
1.1 deraadt 1473:
1474: #ifdef PACKET_DEBUG
1.14 markus 1475: fprintf(stderr, "read_poll plain: ");
1.201 markus 1476: sshbuf_dump(state->incoming_packet, stderr);
1.1 deraadt 1477: #endif
1478:
1.14 markus 1479: /* Compute packet checksum. */
1.201 markus 1480: checksum = ssh_crc32(sshbuf_ptr(state->incoming_packet),
1481: sshbuf_len(state->incoming_packet) - 4);
1.14 markus 1482:
1483: /* Skip padding. */
1.201 markus 1484: if ((r = sshbuf_consume(state->incoming_packet, 8 - len % 8)) != 0)
1485: goto out;
1.14 markus 1486:
1487: /* Test check bytes. */
1.205 djm 1488: if (len != sshbuf_len(state->incoming_packet)) {
1489: error("%s: len %d != sshbuf_len %zd", __func__,
1.201 markus 1490: len, sshbuf_len(state->incoming_packet));
1.205 djm 1491: if ((r = sshpkt_disconnect(ssh, "invalid packet length")) != 0 ||
1492: (r = ssh_packet_write_wait(ssh)) != 0)
1493: return r;
1494: return SSH_ERR_CONN_CORRUPT;
1495: }
1.14 markus 1496:
1.201 markus 1497: cp = sshbuf_ptr(state->incoming_packet) + len - 4;
1498: stored_checksum = PEEK_U32(cp);
1.205 djm 1499: if (checksum != stored_checksum) {
1500: error("Corrupted check bytes on input");
1501: if ((r = sshpkt_disconnect(ssh, "connection corrupted")) != 0 ||
1502: (r = ssh_packet_write_wait(ssh)) != 0)
1503: return r;
1504: return SSH_ERR_CONN_CORRUPT;
1505: }
1.201 markus 1506: if ((r = sshbuf_consume_end(state->incoming_packet, 4)) < 0)
1507: goto out;
1508:
1509: if (state->packet_compression) {
1510: sshbuf_reset(state->compression_buffer);
1511: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1512: state->compression_buffer)) != 0)
1513: goto out;
1514: sshbuf_reset(state->incoming_packet);
1515: if ((r = sshbuf_putb(state->incoming_packet,
1516: state->compression_buffer)) != 0)
1517: goto out;
1518: }
1519: state->p_read.packets++;
1520: state->p_read.bytes += padded_len + 4;
1521: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1522: goto out;
1.205 djm 1523: if (*typep < SSH_MSG_MIN || *typep > SSH_MSG_MAX) {
1524: error("Invalid ssh1 packet type: %d", *typep);
1525: if ((r = sshpkt_disconnect(ssh, "invalid packet type")) != 0 ||
1526: (r = ssh_packet_write_wait(ssh)) != 0)
1527: return r;
1528: return SSH_ERR_PROTOCOL_ERROR;
1529: }
1.201 markus 1530: r = 0;
1531: out:
1532: return r;
1.1 deraadt 1533: }
1.14 markus 1534:
1.242 markus 1535: static int
1536: ssh_packet_read_poll2_mux(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1537: {
1538: struct session_state *state = ssh->state;
1539: const u_char *cp;
1540: size_t need;
1541: int r;
1542:
1543: if (ssh->kex)
1544: return SSH_ERR_INTERNAL_ERROR;
1545: *typep = SSH_MSG_NONE;
1546: cp = sshbuf_ptr(state->input);
1547: if (state->packlen == 0) {
1548: if (sshbuf_len(state->input) < 4 + 1)
1549: return 0; /* packet is incomplete */
1550: state->packlen = PEEK_U32(cp);
1551: if (state->packlen < 4 + 1 ||
1552: state->packlen > PACKET_MAX_SIZE)
1553: return SSH_ERR_MESSAGE_INCOMPLETE;
1554: }
1555: need = state->packlen + 4;
1556: if (sshbuf_len(state->input) < need)
1557: return 0; /* packet is incomplete */
1558: sshbuf_reset(state->incoming_packet);
1559: if ((r = sshbuf_put(state->incoming_packet, cp + 4,
1560: state->packlen)) != 0 ||
1561: (r = sshbuf_consume(state->input, need)) != 0 ||
1562: (r = sshbuf_get_u8(state->incoming_packet, NULL)) != 0 ||
1563: (r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1564: return r;
1565: if (ssh_packet_log_type(*typep))
1566: debug3("%s: type %u", __func__, *typep);
1567: /* sshbuf_dump(state->incoming_packet, stderr); */
1568: /* reset for next packet */
1569: state->packlen = 0;
1570: return r;
1571: }
1572:
1.201 markus 1573: int
1574: ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1575: {
1.201 markus 1576: struct session_state *state = ssh->state;
1.40 markus 1577: u_int padlen, need;
1.231 djm 1578: u_char *cp;
1.201 markus 1579: u_int maclen, aadlen = 0, authlen = 0, block_size;
1580: struct sshenc *enc = NULL;
1581: struct sshmac *mac = NULL;
1582: struct sshcomp *comp = NULL;
1.200 markus 1583: int r;
1.201 markus 1584:
1.242 markus 1585: if (state->mux)
1586: return ssh_packet_read_poll2_mux(ssh, typep, seqnr_p);
1587:
1.201 markus 1588: *typep = SSH_MSG_NONE;
1589:
1590: if (state->packet_discard)
1591: return 0;
1592:
1593: if (state->newkeys[MODE_IN] != NULL) {
1594: enc = &state->newkeys[MODE_IN]->enc;
1595: mac = &state->newkeys[MODE_IN]->mac;
1596: comp = &state->newkeys[MODE_IN]->comp;
1.180 markus 1597: /* disable mac for authenticated encryption */
1598: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1599: mac = NULL;
1.25 markus 1600: }
1601: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.88 markus 1602: block_size = enc ? enc->block_size : 8;
1.180 markus 1603: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1604:
1.201 markus 1605: if (aadlen && state->packlen == 0) {
1.235 djm 1606: if (cipher_get_length(state->receive_context,
1.201 markus 1607: &state->packlen, state->p_read.seqnr,
1608: sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1609: return 0;
1610: if (state->packlen < 1 + 4 ||
1611: state->packlen > PACKET_MAX_SIZE) {
1.178 markus 1612: #ifdef PACKET_DEBUG
1.201 markus 1613: sshbuf_dump(state->input, stderr);
1.178 markus 1614: #endif
1.201 markus 1615: logit("Bad packet length %u.", state->packlen);
1616: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1617: return r;
1.217 djm 1618: return SSH_ERR_CONN_CORRUPT;
1.178 markus 1619: }
1.201 markus 1620: sshbuf_reset(state->incoming_packet);
1621: } else if (state->packlen == 0) {
1.25 markus 1622: /*
1623: * check if input size is less than the cipher block size,
1624: * decrypt first block and extract length of incoming packet
1625: */
1.201 markus 1626: if (sshbuf_len(state->input) < block_size)
1627: return 0;
1628: sshbuf_reset(state->incoming_packet);
1629: if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1630: &cp)) != 0)
1631: goto out;
1.235 djm 1632: if ((r = cipher_crypt(state->receive_context,
1.201 markus 1633: state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1634: block_size, 0, 0)) != 0)
1635: goto out;
1636: state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1637: if (state->packlen < 1 + 4 ||
1638: state->packlen > PACKET_MAX_SIZE) {
1.110 markus 1639: #ifdef PACKET_DEBUG
1.201 markus 1640: fprintf(stderr, "input: \n");
1641: sshbuf_dump(state->input, stderr);
1642: fprintf(stderr, "incoming_packet: \n");
1643: sshbuf_dump(state->incoming_packet, stderr);
1.110 markus 1644: #endif
1.201 markus 1645: logit("Bad packet length %u.", state->packlen);
1.234 markus 1646: return ssh_packet_start_discard(ssh, enc, mac, 0,
1647: PACKET_MAX_SIZE);
1.25 markus 1648: }
1.201 markus 1649: if ((r = sshbuf_consume(state->input, block_size)) != 0)
1650: goto out;
1.25 markus 1651: }
1.201 markus 1652: DBG(debug("input: packet len %u", state->packlen+4));
1653:
1.178 markus 1654: if (aadlen) {
1655: /* only the payload is encrypted */
1.201 markus 1656: need = state->packlen;
1.178 markus 1657: } else {
1658: /*
1659: * the payload size and the payload are encrypted, but we
1660: * have a partial packet of block_size bytes
1661: */
1.201 markus 1662: need = 4 + state->packlen - block_size;
1.178 markus 1663: }
1.180 markus 1664: DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1665: " aadlen %d", block_size, need, maclen, authlen, aadlen));
1.158 markus 1666: if (need % block_size != 0) {
1667: logit("padding error: need %d block %d mod %d",
1.25 markus 1668: need, block_size, need % block_size);
1.234 markus 1669: return ssh_packet_start_discard(ssh, enc, mac, 0,
1670: PACKET_MAX_SIZE - block_size);
1.158 markus 1671: }
1.25 markus 1672: /*
1673: * check if the entire packet has been received and
1.178 markus 1674: * decrypt into incoming_packet:
1675: * 'aadlen' bytes are unencrypted, but authenticated.
1.180 markus 1676: * 'need' bytes are encrypted, followed by either
1677: * 'authlen' bytes of authentication tag or
1.178 markus 1678: * 'maclen' bytes of message authentication code.
1.25 markus 1679: */
1.201 markus 1680: if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1.231 djm 1681: return 0; /* packet is incomplete */
1.25 markus 1682: #ifdef PACKET_DEBUG
1683: fprintf(stderr, "read_poll enc/full: ");
1.201 markus 1684: sshbuf_dump(state->input, stderr);
1.25 markus 1685: #endif
1.231 djm 1686: /* EtM: check mac over encrypted input */
1.201 markus 1687: if (mac && mac->enabled && mac->etm) {
1.231 djm 1688: if ((r = mac_check(mac, state->p_read.seqnr,
1.201 markus 1689: sshbuf_ptr(state->input), aadlen + need,
1.231 djm 1690: sshbuf_ptr(state->input) + aadlen + need + authlen,
1691: maclen)) != 0) {
1692: if (r == SSH_ERR_MAC_INVALID)
1693: logit("Corrupted MAC on input.");
1.201 markus 1694: goto out;
1.231 djm 1695: }
1.201 markus 1696: }
1697: if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1698: &cp)) != 0)
1699: goto out;
1.235 djm 1700: if ((r = cipher_crypt(state->receive_context, state->p_read.seqnr, cp,
1.201 markus 1701: sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1702: goto out;
1703: if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1704: goto out;
1.29 markus 1705: if (mac && mac->enabled) {
1.231 djm 1706: /* Not EtM: check MAC over cleartext */
1707: if (!mac->etm && (r = mac_check(mac, state->p_read.seqnr,
1708: sshbuf_ptr(state->incoming_packet),
1709: sshbuf_len(state->incoming_packet),
1710: sshbuf_ptr(state->input), maclen)) != 0) {
1711: if (r != SSH_ERR_MAC_INVALID)
1.201 markus 1712: goto out;
1.159 markus 1713: logit("Corrupted MAC on input.");
1.247 markus 1714: if (need + block_size > PACKET_MAX_SIZE)
1.201 markus 1715: return SSH_ERR_INTERNAL_ERROR;
1716: return ssh_packet_start_discard(ssh, enc, mac,
1.234 markus 1717: sshbuf_len(state->incoming_packet),
1.247 markus 1718: PACKET_MAX_SIZE - need - block_size);
1.201 markus 1719: }
1.231 djm 1720: /* Remove MAC from input buffer */
1.201 markus 1721: DBG(debug("MAC #%d ok", state->p_read.seqnr));
1722: if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1723: goto out;
1.25 markus 1724: }
1.77 djm 1725: if (seqnr_p != NULL)
1.201 markus 1726: *seqnr_p = state->p_read.seqnr;
1727: if (++state->p_read.seqnr == 0)
1.106 itojun 1728: logit("incoming seqnr wraps around");
1.201 markus 1729: if (++state->p_read.packets == 0)
1730: if (!(ssh->compat & SSH_BUG_NOREKEY))
1731: return SSH_ERR_NEED_REKEY;
1732: state->p_read.blocks += (state->packlen + 4) / block_size;
1733: state->p_read.bytes += state->packlen + 4;
1.25 markus 1734:
1735: /* get padlen */
1.201 markus 1736: padlen = sshbuf_ptr(state->incoming_packet)[4];
1.25 markus 1737: DBG(debug("input: padlen %d", padlen));
1.205 djm 1738: if (padlen < 4) {
1739: if ((r = sshpkt_disconnect(ssh,
1740: "Corrupted padlen %d on input.", padlen)) != 0 ||
1741: (r = ssh_packet_write_wait(ssh)) != 0)
1742: return r;
1743: return SSH_ERR_CONN_CORRUPT;
1744: }
1.25 markus 1745:
1746: /* skip packet size + padlen, discard padding */
1.201 markus 1747: if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1748: ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1749: goto out;
1.25 markus 1750:
1.201 markus 1751: DBG(debug("input: len before de-compress %zd",
1752: sshbuf_len(state->incoming_packet)));
1.25 markus 1753: if (comp && comp->enabled) {
1.201 markus 1754: sshbuf_reset(state->compression_buffer);
1755: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1756: state->compression_buffer)) != 0)
1757: goto out;
1758: sshbuf_reset(state->incoming_packet);
1759: if ((r = sshbuf_putb(state->incoming_packet,
1760: state->compression_buffer)) != 0)
1761: goto out;
1762: DBG(debug("input: len after de-compress %zd",
1763: sshbuf_len(state->incoming_packet)));
1.25 markus 1764: }
1765: /*
1766: * get packet type, implies consume.
1767: * return length of payload (without type field)
1768: */
1.201 markus 1769: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1770: goto out;
1.226 djm 1771: if (ssh_packet_log_type(*typep))
1772: debug3("receive packet: type %u", *typep);
1.205 djm 1773: if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1774: if ((r = sshpkt_disconnect(ssh,
1775: "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1776: (r = ssh_packet_write_wait(ssh)) != 0)
1777: return r;
1778: return SSH_ERR_PROTOCOL_ERROR;
1779: }
1.243 djm 1780: if (state->hook_in != NULL &&
1781: (r = state->hook_in(ssh, state->incoming_packet, typep,
1782: state->hook_in_ctx)) != 0)
1783: return r;
1.238 markus 1784: if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1.201 markus 1785: r = ssh_packet_enable_delayed_compress(ssh);
1786: else
1787: r = 0;
1.25 markus 1788: #ifdef PACKET_DEBUG
1.201 markus 1789: fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1790: sshbuf_dump(state->incoming_packet, stderr);
1.25 markus 1791: #endif
1.62 markus 1792: /* reset for next packet */
1.201 markus 1793: state->packlen = 0;
1.228 djm 1794:
1795: /* do we need to rekey? */
1796: if (ssh_packet_need_rekeying(ssh, 0)) {
1797: debug3("%s: rekex triggered", __func__);
1798: if ((r = kex_start_rekex(ssh)) != 0)
1799: return r;
1800: }
1.201 markus 1801: out:
1802: return r;
1.25 markus 1803: }
1804:
1805: int
1.201 markus 1806: ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1807: {
1.201 markus 1808: struct session_state *state = ssh->state;
1.96 deraadt 1809: u_int reason, seqnr;
1.201 markus 1810: int r;
1811: u_char *msg;
1.62 markus 1812:
1.25 markus 1813: for (;;) {
1.201 markus 1814: msg = NULL;
1.249 ! djm 1815: r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
! 1816: if (r != 0)
! 1817: return r;
! 1818: if (*typep) {
! 1819: state->keep_alive_timeouts = 0;
! 1820: DBG(debug("received packet type %d", *typep));
! 1821: }
! 1822: switch (*typep) {
! 1823: case SSH2_MSG_IGNORE:
! 1824: debug3("Received SSH2_MSG_IGNORE");
! 1825: break;
! 1826: case SSH2_MSG_DEBUG:
! 1827: if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
! 1828: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
! 1829: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
! 1830: free(msg);
1.201 markus 1831: return r;
1.48 stevesk 1832: }
1.249 ! djm 1833: debug("Remote: %.900s", msg);
! 1834: free(msg);
! 1835: break;
! 1836: case SSH2_MSG_DISCONNECT:
! 1837: if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
! 1838: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
! 1839: return r;
! 1840: /* Ignore normal client exit notifications */
! 1841: do_log2(ssh->state->server_side &&
! 1842: reason == SSH2_DISCONNECT_BY_APPLICATION ?
! 1843: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
! 1844: "Received disconnect from %s port %d:"
! 1845: "%u: %.400s", ssh_remote_ipaddr(ssh),
! 1846: ssh_remote_port(ssh), reason, msg);
! 1847: free(msg);
! 1848: return SSH_ERR_DISCONNECTED;
! 1849: case SSH2_MSG_UNIMPLEMENTED:
! 1850: if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
! 1851: return r;
! 1852: debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
! 1853: seqnr);
! 1854: break;
! 1855: default:
! 1856: return 0;
1.25 markus 1857: }
1858: }
1859: }
1860:
1.16 markus 1861: /*
1862: * Buffers the given amount of input characters. This is intended to be used
1863: * together with packet_read_poll.
1864: */
1.1 deraadt 1865:
1.204 djm 1866: int
1.201 markus 1867: ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1.1 deraadt 1868: {
1.201 markus 1869: struct session_state *state = ssh->state;
1870: int r;
1871:
1872: if (state->packet_discard) {
1873: state->keep_alive_timeouts = 0; /* ?? */
1874: if (len >= state->packet_discard) {
1875: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1.204 djm 1876: return r;
1.201 markus 1877: }
1878: state->packet_discard -= len;
1.204 djm 1879: return 0;
1.159 markus 1880: }
1.201 markus 1881: if ((r = sshbuf_put(ssh->state->input, buf, len)) != 0)
1.204 djm 1882: return r;
1883:
1884: return 0;
1.28 markus 1885: }
1886:
1887: int
1.201 markus 1888: ssh_packet_remaining(struct ssh *ssh)
1.28 markus 1889: {
1.201 markus 1890: return sshbuf_len(ssh->state->incoming_packet);
1.1 deraadt 1891: }
1892:
1.16 markus 1893: /*
1894: * Sends a diagnostic message from the server to the client. This message
1895: * can be sent at any time (but not while constructing another message). The
1896: * message is printed immediately, but only if the client is being executed
1897: * in verbose mode. These messages are primarily intended to ease debugging
1898: * authentication problems. The length of the formatted message must not
1.205 djm 1899: * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1.16 markus 1900: */
1.2 provos 1901: void
1.201 markus 1902: ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1903: {
1.14 markus 1904: char buf[1024];
1905: va_list args;
1.201 markus 1906: int r;
1.39 markus 1907:
1.249 ! djm 1908: if ((ssh->compat & SSH_BUG_DEBUG))
1.39 markus 1909: return;
1.14 markus 1910:
1911: va_start(args, fmt);
1912: vsnprintf(buf, sizeof(buf), fmt, args);
1913: va_end(args);
1914:
1.249 ! djm 1915: if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
! 1916: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
! 1917: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
! 1918: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
! 1919: (r = sshpkt_send(ssh)) != 0 ||
! 1920: (r = ssh_packet_write_wait(ssh)) != 0)
1.205 djm 1921: fatal("%s: %s", __func__, ssh_err(r));
1922: }
1923:
1.245 djm 1924: static void
1925: fmt_connection_id(struct ssh *ssh, char *s, size_t l)
1926: {
1927: snprintf(s, l, "%.200s%s%s port %d",
1928: ssh->log_preamble ? ssh->log_preamble : "",
1929: ssh->log_preamble ? " " : "",
1930: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1931: }
1932:
1.205 djm 1933: /*
1934: * Pretty-print connection-terminating errors and exit.
1935: */
1936: void
1937: sshpkt_fatal(struct ssh *ssh, const char *tag, int r)
1938: {
1.245 djm 1939: char remote_id[512];
1940:
1941: fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1942:
1.205 djm 1943: switch (r) {
1944: case SSH_ERR_CONN_CLOSED:
1.245 djm 1945: logdie("Connection closed by %s", remote_id);
1.205 djm 1946: case SSH_ERR_CONN_TIMEOUT:
1.245 djm 1947: logdie("Connection %s %s timed out",
1948: ssh->state->server_side ? "from" : "to", remote_id);
1.212 djm 1949: case SSH_ERR_DISCONNECTED:
1.245 djm 1950: logdie("Disconnected from %s", remote_id);
1.212 djm 1951: case SSH_ERR_SYSTEM_ERROR:
1.232 dtucker 1952: if (errno == ECONNRESET)
1.245 djm 1953: logdie("Connection reset by %s", remote_id);
1.213 djm 1954: /* FALLTHROUGH */
1955: case SSH_ERR_NO_CIPHER_ALG_MATCH:
1956: case SSH_ERR_NO_MAC_ALG_MATCH:
1957: case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1958: case SSH_ERR_NO_KEX_ALG_MATCH:
1959: case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1960: if (ssh && ssh->kex && ssh->kex->failed_choice) {
1.245 djm 1961: logdie("Unable to negotiate with %s: %s. "
1962: "Their offer: %s", remote_id, ssh_err(r),
1.220 djm 1963: ssh->kex->failed_choice);
1.212 djm 1964: }
1965: /* FALLTHROUGH */
1.205 djm 1966: default:
1.245 djm 1967: logdie("%s%sConnection %s %s: %s",
1.205 djm 1968: tag != NULL ? tag : "", tag != NULL ? ": " : "",
1.220 djm 1969: ssh->state->server_side ? "from" : "to",
1.245 djm 1970: remote_id, ssh_err(r));
1.205 djm 1971: }
1.1 deraadt 1972: }
1973:
1.16 markus 1974: /*
1975: * Logs the error plus constructs and sends a disconnect packet, closes the
1976: * connection, and exits. This function never returns. The error message
1977: * should not contain a newline. The length of the formatted message must
1978: * not exceed 1024 bytes.
1979: */
1.2 provos 1980: void
1.201 markus 1981: ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1982: {
1.245 djm 1983: char buf[1024], remote_id[512];
1.14 markus 1984: va_list args;
1985: static int disconnecting = 0;
1.201 markus 1986: int r;
1.97 deraadt 1987:
1.14 markus 1988: if (disconnecting) /* Guard against recursive invocations. */
1989: fatal("packet_disconnect called recursively.");
1990: disconnecting = 1;
1991:
1.16 markus 1992: /*
1993: * Format the message. Note that the caller must make sure the
1994: * message is of limited size.
1995: */
1.245 djm 1996: fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1.14 markus 1997: va_start(args, fmt);
1998: vsnprintf(buf, sizeof(buf), fmt, args);
1999: va_end(args);
2000:
1.99 markus 2001: /* Display the error locally */
1.245 djm 2002: logit("Disconnecting %s: %.100s", remote_id, buf);
1.99 markus 2003:
1.205 djm 2004: /*
2005: * Send the disconnect message to the other side, and wait
2006: * for it to get sent.
2007: */
2008: if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
2009: sshpkt_fatal(ssh, __func__, r);
2010:
2011: if ((r = ssh_packet_write_wait(ssh)) != 0)
2012: sshpkt_fatal(ssh, __func__, r);
1.14 markus 2013:
2014: /* Close the connection. */
1.201 markus 2015: ssh_packet_close(ssh);
1.112 markus 2016: cleanup_exit(255);
1.1 deraadt 2017: }
2018:
1.205 djm 2019: /*
2020: * Checks if there is any buffered output, and tries to write some of
2021: * the output.
2022: */
2023: int
1.201 markus 2024: ssh_packet_write_poll(struct ssh *ssh)
1.1 deraadt 2025: {
1.201 markus 2026: struct session_state *state = ssh->state;
2027: int len = sshbuf_len(state->output);
1.222 markus 2028: int r;
1.97 deraadt 2029:
1.14 markus 2030: if (len > 0) {
1.222 markus 2031: len = write(state->connection_out,
2032: sshbuf_ptr(state->output), len);
1.156 djm 2033: if (len == -1) {
2034: if (errno == EINTR || errno == EAGAIN)
1.205 djm 2035: return 0;
2036: return SSH_ERR_SYSTEM_ERROR;
1.14 markus 2037: }
1.222 markus 2038: if (len == 0)
1.205 djm 2039: return SSH_ERR_CONN_CLOSED;
1.201 markus 2040: if ((r = sshbuf_consume(state->output, len)) != 0)
1.205 djm 2041: return r;
1.14 markus 2042: }
1.205 djm 2043: return 0;
1.1 deraadt 2044: }
2045:
1.16 markus 2046: /*
2047: * Calls packet_write_poll repeatedly until all pending output data has been
2048: * written.
2049: */
1.205 djm 2050: int
1.201 markus 2051: ssh_packet_write_wait(struct ssh *ssh)
1.1 deraadt 2052: {
1.56 millert 2053: fd_set *setp;
1.205 djm 2054: int ret, r, ms_remain = 0;
1.154 dtucker 2055: struct timeval start, timeout, *timeoutp = NULL;
1.201 markus 2056: struct session_state *state = ssh->state;
1.56 millert 2057:
1.214 deraadt 2058: setp = calloc(howmany(state->connection_out + 1,
1.161 andreas 2059: NFDBITS), sizeof(fd_mask));
1.201 markus 2060: if (setp == NULL)
1.205 djm 2061: return SSH_ERR_ALLOC_FAIL;
1.216 gsoares 2062: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2063: free(setp);
1.215 djm 2064: return r;
1.216 gsoares 2065: }
1.201 markus 2066: while (ssh_packet_have_data_to_write(ssh)) {
2067: memset(setp, 0, howmany(state->connection_out + 1,
1.161 andreas 2068: NFDBITS) * sizeof(fd_mask));
1.201 markus 2069: FD_SET(state->connection_out, setp);
1.154 dtucker 2070:
1.201 markus 2071: if (state->packet_timeout_ms > 0) {
2072: ms_remain = state->packet_timeout_ms;
1.154 dtucker 2073: timeoutp = &timeout;
2074: }
2075: for (;;) {
1.201 markus 2076: if (state->packet_timeout_ms != -1) {
1.154 dtucker 2077: ms_to_timeval(&timeout, ms_remain);
2078: gettimeofday(&start, NULL);
2079: }
1.201 markus 2080: if ((ret = select(state->connection_out + 1,
1.161 andreas 2081: NULL, setp, NULL, timeoutp)) >= 0)
1.154 dtucker 2082: break;
1.161 andreas 2083: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 2084: break;
1.201 markus 2085: if (state->packet_timeout_ms == -1)
1.154 dtucker 2086: continue;
2087: ms_subtract_diff(&start, &ms_remain);
2088: if (ms_remain <= 0) {
2089: ret = 0;
2090: break;
2091: }
2092: }
2093: if (ret == 0) {
1.205 djm 2094: free(setp);
2095: return SSH_ERR_CONN_TIMEOUT;
2096: }
2097: if ((r = ssh_packet_write_poll(ssh)) != 0) {
2098: free(setp);
2099: return r;
1.154 dtucker 2100: }
1.14 markus 2101: }
1.186 djm 2102: free(setp);
1.205 djm 2103: return 0;
1.1 deraadt 2104: }
2105:
2106: /* Returns true if there is buffered data to write to the connection. */
2107:
1.2 provos 2108: int
1.201 markus 2109: ssh_packet_have_data_to_write(struct ssh *ssh)
1.1 deraadt 2110: {
1.201 markus 2111: return sshbuf_len(ssh->state->output) != 0;
1.1 deraadt 2112: }
2113:
2114: /* Returns true if there is not too much data to write to the connection. */
2115:
1.2 provos 2116: int
1.201 markus 2117: ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1.1 deraadt 2118: {
1.201 markus 2119: if (ssh->state->interactive_mode)
2120: return sshbuf_len(ssh->state->output) < 16384;
1.14 markus 2121: else
1.201 markus 2122: return sshbuf_len(ssh->state->output) < 128 * 1024;
1.1 deraadt 2123: }
2124:
1.201 markus 2125: void
2126: ssh_packet_set_tos(struct ssh *ssh, int tos)
1.101 markus 2127: {
1.201 markus 2128: if (!ssh_packet_connection_is_on_socket(ssh))
1.101 markus 2129: return;
1.201 markus 2130: switch (ssh_packet_connection_af(ssh)) {
1.173 djm 2131: case AF_INET:
2132: debug3("%s: set IP_TOS 0x%02x", __func__, tos);
1.201 markus 2133: if (setsockopt(ssh->state->connection_in,
1.173 djm 2134: IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0)
2135: error("setsockopt IP_TOS %d: %.100s:",
2136: tos, strerror(errno));
2137: break;
2138: case AF_INET6:
2139: debug3("%s: set IPV6_TCLASS 0x%02x", __func__, tos);
1.201 markus 2140: if (setsockopt(ssh->state->connection_in,
1.173 djm 2141: IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
2142: error("setsockopt IPV6_TCLASS %d: %.100s:",
2143: tos, strerror(errno));
2144: break;
2145: }
1.101 markus 2146: }
2147:
1.1 deraadt 2148: /* Informs that the current session is interactive. Sets IP flags for that. */
2149:
1.2 provos 2150: void
1.201 markus 2151: ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
1.1 deraadt 2152: {
1.201 markus 2153: struct session_state *state = ssh->state;
2154:
2155: if (state->set_interactive_called)
1.43 markus 2156: return;
1.201 markus 2157: state->set_interactive_called = 1;
1.1 deraadt 2158:
1.14 markus 2159: /* Record that we are in interactive mode. */
1.201 markus 2160: state->interactive_mode = interactive;
1.1 deraadt 2161:
1.19 markus 2162: /* Only set socket options if using a socket. */
1.201 markus 2163: if (!ssh_packet_connection_is_on_socket(ssh))
1.14 markus 2164: return;
1.201 markus 2165: set_nodelay(state->connection_in);
2166: ssh_packet_set_tos(ssh, interactive ? qos_interactive :
2167: qos_bulk);
1.1 deraadt 2168: }
2169:
2170: /* Returns true if the current connection is interactive. */
2171:
1.2 provos 2172: int
1.201 markus 2173: ssh_packet_is_interactive(struct ssh *ssh)
1.1 deraadt 2174: {
1.201 markus 2175: return ssh->state->interactive_mode;
1.12 markus 2176: }
2177:
1.113 deraadt 2178: int
1.201 markus 2179: ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
1.12 markus 2180: {
1.201 markus 2181: struct session_state *state = ssh->state;
2182:
2183: if (state->set_maxsize_called) {
1.106 itojun 2184: logit("packet_set_maxsize: called twice: old %d new %d",
1.201 markus 2185: state->max_packet_size, s);
1.14 markus 2186: return -1;
2187: }
2188: if (s < 4 * 1024 || s > 1024 * 1024) {
1.106 itojun 2189: logit("packet_set_maxsize: bad size %d", s);
1.14 markus 2190: return -1;
2191: }
1.201 markus 2192: state->set_maxsize_called = 1;
1.66 markus 2193: debug("packet_set_maxsize: setting to %d", s);
1.201 markus 2194: state->max_packet_size = s;
1.14 markus 2195: return s;
1.53 markus 2196: }
2197:
1.161 andreas 2198: int
1.201 markus 2199: ssh_packet_inc_alive_timeouts(struct ssh *ssh)
1.161 andreas 2200: {
1.201 markus 2201: return ++ssh->state->keep_alive_timeouts;
1.161 andreas 2202: }
2203:
2204: void
1.201 markus 2205: ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
1.161 andreas 2206: {
1.201 markus 2207: ssh->state->keep_alive_timeouts = ka;
1.161 andreas 2208: }
2209:
2210: u_int
1.201 markus 2211: ssh_packet_get_maxsize(struct ssh *ssh)
1.71 markus 2212: {
1.201 markus 2213: return ssh->state->max_packet_size;
1.71 markus 2214: }
2215:
1.53 markus 2216: /*
2217: * 9.2. Ignored Data Message
1.61 markus 2218: *
1.53 markus 2219: * byte SSH_MSG_IGNORE
2220: * string data
1.61 markus 2221: *
1.53 markus 2222: * All implementations MUST understand (and ignore) this message at any
2223: * time (after receiving the protocol version). No implementation is
2224: * required to send them. This message can be used as an additional
2225: * protection measure against advanced traffic analysis techniques.
2226: */
1.54 markus 2227: void
1.201 markus 2228: ssh_packet_send_ignore(struct ssh *ssh, int nbytes)
1.54 markus 2229: {
1.115 avsm 2230: u_int32_t rnd = 0;
1.201 markus 2231: int r, i;
1.54 markus 2232:
1.249 ! djm 2233: if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
1.201 markus 2234: (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2235: fatal("%s: %s", __func__, ssh_err(r));
1.75 deraadt 2236: for (i = 0; i < nbytes; i++) {
1.53 markus 2237: if (i % 4 == 0)
1.115 avsm 2238: rnd = arc4random();
1.201 markus 2239: if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2240: fatal("%s: %s", __func__, ssh_err(r));
1.115 avsm 2241: rnd >>= 8;
1.53 markus 2242: }
1.105 markus 2243: }
2244:
2245: void
1.244 dtucker 2246: ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, u_int32_t seconds)
1.105 markus 2247: {
1.244 dtucker 2248: debug3("rekey after %llu bytes, %u seconds", (unsigned long long)bytes,
2249: (unsigned int)seconds);
1.201 markus 2250: ssh->state->rekey_limit = bytes;
2251: ssh->state->rekey_interval = seconds;
1.184 dtucker 2252: }
2253:
2254: time_t
1.201 markus 2255: ssh_packet_get_rekey_timeout(struct ssh *ssh)
1.184 dtucker 2256: {
2257: time_t seconds;
2258:
1.201 markus 2259: seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
1.187 dtucker 2260: monotime();
1.185 dtucker 2261: return (seconds <= 0 ? 1 : seconds);
1.118 markus 2262: }
2263:
2264: void
1.201 markus 2265: ssh_packet_set_server(struct ssh *ssh)
1.118 markus 2266: {
1.201 markus 2267: ssh->state->server_side = 1;
1.118 markus 2268: }
2269:
2270: void
1.201 markus 2271: ssh_packet_set_authenticated(struct ssh *ssh)
1.118 markus 2272: {
1.201 markus 2273: ssh->state->after_authentication = 1;
1.161 andreas 2274: }
2275:
2276: void *
1.201 markus 2277: ssh_packet_get_input(struct ssh *ssh)
1.161 andreas 2278: {
1.201 markus 2279: return (void *)ssh->state->input;
1.161 andreas 2280: }
2281:
2282: void *
1.201 markus 2283: ssh_packet_get_output(struct ssh *ssh)
1.161 andreas 2284: {
1.201 markus 2285: return (void *)ssh->state->output;
1.166 andreas 2286: }
2287:
1.196 markus 2288: /* Reset after_authentication and reset compression in post-auth privsep */
1.201 markus 2289: static int
2290: ssh_packet_set_postauth(struct ssh *ssh)
1.196 markus 2291: {
1.239 djm 2292: int r;
1.196 markus 2293:
2294: debug("%s: called", __func__);
2295: /* This was set in net child, but is not visible in user child */
1.201 markus 2296: ssh->state->after_authentication = 1;
2297: ssh->state->rekeying = 0;
1.239 djm 2298: if ((r = ssh_packet_enable_delayed_compress(ssh)) != 0)
2299: return r;
1.201 markus 2300: return 0;
2301: }
2302:
2303: /* Packet state (de-)serialization for privsep */
2304:
2305: /* turn kex into a blob for packet state serialization */
2306: static int
2307: kex_to_blob(struct sshbuf *m, struct kex *kex)
2308: {
2309: int r;
2310:
2311: if ((r = sshbuf_put_string(m, kex->session_id,
2312: kex->session_id_len)) != 0 ||
2313: (r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
2314: (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
2315: (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
2316: (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2317: (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
2318: (r = sshbuf_put_u32(m, kex->flags)) != 0 ||
2319: (r = sshbuf_put_cstring(m, kex->client_version_string)) != 0 ||
2320: (r = sshbuf_put_cstring(m, kex->server_version_string)) != 0)
2321: return r;
2322: return 0;
2323: }
2324:
2325: /* turn key exchange results into a blob for packet state serialization */
2326: static int
2327: newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2328: {
2329: struct sshbuf *b;
2330: struct sshcipher_ctx *cc;
2331: struct sshcomp *comp;
2332: struct sshenc *enc;
2333: struct sshmac *mac;
2334: struct newkeys *newkey;
2335: int r;
2336:
2337: if ((newkey = ssh->state->newkeys[mode]) == NULL)
2338: return SSH_ERR_INTERNAL_ERROR;
2339: enc = &newkey->enc;
2340: mac = &newkey->mac;
2341: comp = &newkey->comp;
1.235 djm 2342: cc = (mode == MODE_OUT) ? ssh->state->send_context :
2343: ssh->state->receive_context;
1.201 markus 2344: if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2345: return r;
2346: if ((b = sshbuf_new()) == NULL)
2347: return SSH_ERR_ALLOC_FAIL;
2348: /* The cipher struct is constant and shared, you export pointer */
2349: if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2350: (r = sshbuf_put(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2351: (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2352: (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2353: (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2354: (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2355: goto out;
2356: if (cipher_authlen(enc->cipher) == 0) {
2357: if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2358: (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2359: (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2360: goto out;
2361: }
2362: if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2363: (r = sshbuf_put_cstring(b, comp->name)) != 0)
2364: goto out;
2365: r = sshbuf_put_stringb(m, b);
2366: out:
1.221 mmcc 2367: sshbuf_free(b);
1.201 markus 2368: return r;
2369: }
2370:
2371: /* serialize packet state into a blob */
2372: int
2373: ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2374: {
2375: struct session_state *state = ssh->state;
2376: u_char *p;
2377: size_t slen, rlen;
1.249 ! djm 2378: int r;
1.201 markus 2379:
1.249 ! djm 2380: if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
! 2381: (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
! 2382: (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
! 2383: (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
! 2384: (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
! 2385: (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
! 2386: (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
! 2387: (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
! 2388: (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
! 2389: (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
! 2390: (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
! 2391: (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
! 2392: (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0)
! 2393: return r;
1.201 markus 2394:
1.235 djm 2395: slen = cipher_get_keycontext(state->send_context, NULL);
2396: rlen = cipher_get_keycontext(state->receive_context, NULL);
1.201 markus 2397: if ((r = sshbuf_put_u32(m, slen)) != 0 ||
2398: (r = sshbuf_reserve(m, slen, &p)) != 0)
2399: return r;
1.235 djm 2400: if (cipher_get_keycontext(state->send_context, p) != (int)slen)
1.201 markus 2401: return SSH_ERR_INTERNAL_ERROR;
2402: if ((r = sshbuf_put_u32(m, rlen)) != 0 ||
2403: (r = sshbuf_reserve(m, rlen, &p)) != 0)
2404: return r;
1.235 djm 2405: if (cipher_get_keycontext(state->receive_context, p) != (int)rlen)
1.201 markus 2406: return SSH_ERR_INTERNAL_ERROR;
1.239 djm 2407: if ((r = sshbuf_put_stringb(m, state->input)) != 0 ||
1.201 markus 2408: (r = sshbuf_put_stringb(m, state->output)) != 0)
2409: return r;
2410:
2411: return 0;
2412: }
2413:
2414: /* restore key exchange results from blob for packet state de-serialization */
2415: static int
2416: newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2417: {
2418: struct sshbuf *b = NULL;
2419: struct sshcomp *comp;
2420: struct sshenc *enc;
2421: struct sshmac *mac;
2422: struct newkeys *newkey = NULL;
2423: size_t keylen, ivlen, maclen;
2424: int r;
2425:
2426: if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2427: r = SSH_ERR_ALLOC_FAIL;
2428: goto out;
2429: }
2430: if ((r = sshbuf_froms(m, &b)) != 0)
2431: goto out;
2432: #ifdef DEBUG_PK
2433: sshbuf_dump(b, stderr);
2434: #endif
2435: enc = &newkey->enc;
2436: mac = &newkey->mac;
2437: comp = &newkey->comp;
2438:
2439: if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2440: (r = sshbuf_get(b, &enc->cipher, sizeof(enc->cipher))) != 0 ||
2441: (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2442: (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2443: (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2444: (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2445: goto out;
2446: if (cipher_authlen(enc->cipher) == 0) {
2447: if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2448: goto out;
2449: if ((r = mac_setup(mac, mac->name)) != 0)
2450: goto out;
2451: if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2452: (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2453: goto out;
2454: if (maclen > mac->key_len) {
2455: r = SSH_ERR_INVALID_FORMAT;
2456: goto out;
2457: }
2458: mac->key_len = maclen;
2459: }
2460: if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2461: (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2462: goto out;
2463: if (enc->name == NULL ||
2464: cipher_by_name(enc->name) != enc->cipher) {
2465: r = SSH_ERR_INVALID_FORMAT;
2466: goto out;
2467: }
2468: if (sshbuf_len(b) != 0) {
2469: r = SSH_ERR_INVALID_FORMAT;
2470: goto out;
2471: }
2472: enc->key_len = keylen;
2473: enc->iv_len = ivlen;
2474: ssh->kex->newkeys[mode] = newkey;
2475: newkey = NULL;
2476: r = 0;
2477: out:
1.219 mmcc 2478: free(newkey);
1.221 mmcc 2479: sshbuf_free(b);
1.201 markus 2480: return r;
2481: }
2482:
2483: /* restore kex from blob for packet state de-serialization */
2484: static int
2485: kex_from_blob(struct sshbuf *m, struct kex **kexp)
2486: {
2487: struct kex *kex;
2488: int r;
2489:
2490: if ((kex = calloc(1, sizeof(struct kex))) == NULL ||
2491: (kex->my = sshbuf_new()) == NULL ||
2492: (kex->peer = sshbuf_new()) == NULL) {
2493: r = SSH_ERR_ALLOC_FAIL;
2494: goto out;
2495: }
2496: if ((r = sshbuf_get_string(m, &kex->session_id, &kex->session_id_len)) != 0 ||
2497: (r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
2498: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
2499: (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
2500: (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2501: (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
2502: (r = sshbuf_get_u32(m, &kex->flags)) != 0 ||
2503: (r = sshbuf_get_cstring(m, &kex->client_version_string, NULL)) != 0 ||
2504: (r = sshbuf_get_cstring(m, &kex->server_version_string, NULL)) != 0)
2505: goto out;
2506: kex->server = 1;
2507: kex->done = 1;
2508: r = 0;
2509: out:
2510: if (r != 0 || kexp == NULL) {
2511: if (kex != NULL) {
1.221 mmcc 2512: sshbuf_free(kex->my);
2513: sshbuf_free(kex->peer);
1.201 markus 2514: free(kex);
2515: }
2516: if (kexp != NULL)
2517: *kexp = NULL;
2518: } else {
2519: *kexp = kex;
2520: }
2521: return r;
2522: }
2523:
2524: /*
2525: * Restore packet state from content of blob 'm' (de-serialization).
2526: * Note that 'm' will be partially consumed on parsing or any other errors.
2527: */
2528: int
2529: ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2530: {
2531: struct session_state *state = ssh->state;
1.249 ! djm 2532: const u_char *keyin, *keyout, *input, *output;
! 2533: size_t rlen, slen, ilen, olen;
1.201 markus 2534: int r;
2535:
1.249 ! djm 2536: if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
! 2537: (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
! 2538: (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
! 2539: (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
! 2540: (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
! 2541: (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
! 2542: (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
! 2543: (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
! 2544: (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
! 2545: (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
! 2546: (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
! 2547: (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
! 2548: (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
! 2549: return r;
! 2550: /*
! 2551: * We set the time here so that in post-auth privsep slave we
! 2552: * count from the completion of the authentication.
! 2553: */
! 2554: state->rekey_time = monotime();
! 2555: /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
! 2556: if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
! 2557: (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
! 2558: return r;
! 2559:
1.201 markus 2560: if ((r = sshbuf_get_string_direct(m, &keyout, &slen)) != 0 ||
2561: (r = sshbuf_get_string_direct(m, &keyin, &rlen)) != 0)
2562: return r;
1.235 djm 2563: if (cipher_get_keycontext(state->send_context, NULL) != (int)slen ||
2564: cipher_get_keycontext(state->receive_context, NULL) != (int)rlen)
1.201 markus 2565: return SSH_ERR_INVALID_FORMAT;
1.235 djm 2566: cipher_set_keycontext(state->send_context, keyout);
2567: cipher_set_keycontext(state->receive_context, keyin);
1.201 markus 2568:
1.239 djm 2569: if ((r = ssh_packet_set_postauth(ssh)) != 0)
1.201 markus 2570: return r;
2571:
2572: sshbuf_reset(state->input);
2573: sshbuf_reset(state->output);
2574: if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2575: (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2576: (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2577: (r = sshbuf_put(state->output, output, olen)) != 0)
2578: return r;
2579:
2580: if (sshbuf_len(m))
2581: return SSH_ERR_INVALID_FORMAT;
2582: debug3("%s: done", __func__);
2583: return 0;
2584: }
2585:
2586: /* NEW API */
2587:
2588: /* put data to the outgoing packet */
2589:
2590: int
2591: sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2592: {
2593: return sshbuf_put(ssh->state->outgoing_packet, v, len);
2594: }
2595:
2596: int
2597: sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2598: {
2599: return sshbuf_putb(ssh->state->outgoing_packet, b);
2600: }
2601:
2602: int
2603: sshpkt_put_u8(struct ssh *ssh, u_char val)
2604: {
2605: return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2606: }
2607:
2608: int
2609: sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2610: {
2611: return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2612: }
2613:
2614: int
2615: sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2616: {
2617: return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2618: }
2619:
2620: int
2621: sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2622: {
2623: return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2624: }
2625:
2626: int
2627: sshpkt_put_cstring(struct ssh *ssh, const void *v)
2628: {
2629: return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2630: }
2631:
2632: int
2633: sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2634: {
2635: return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2636: }
2637:
1.211 djm 2638: #ifdef WITH_OPENSSL
1.201 markus 2639: int
2640: sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2641: {
2642: return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2643: }
2644:
2645:
2646: int
2647: sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2648: {
2649: return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2650: }
1.211 djm 2651: #endif /* WITH_OPENSSL */
1.201 markus 2652:
2653: /* fetch data from the incoming packet */
2654:
2655: int
2656: sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2657: {
2658: return sshbuf_get(ssh->state->incoming_packet, valp, len);
2659: }
2660:
2661: int
2662: sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2663: {
2664: return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2665: }
2666:
2667: int
2668: sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2669: {
2670: return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2671: }
2672:
2673: int
2674: sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2675: {
2676: return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2677: }
2678:
2679: int
2680: sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2681: {
2682: return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2683: }
2684:
2685: int
2686: sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2687: {
2688: return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2689: }
2690:
2691: int
2692: sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2693: {
2694: return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
2695: }
2696:
1.211 djm 2697: #ifdef WITH_OPENSSL
1.201 markus 2698: int
2699: sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2700: {
2701: return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2702: }
2703:
2704:
2705: int
2706: sshpkt_get_bignum2(struct ssh *ssh, BIGNUM *v)
2707: {
2708: return sshbuf_get_bignum2(ssh->state->incoming_packet, v);
2709: }
1.211 djm 2710: #endif /* WITH_OPENSSL */
1.201 markus 2711:
2712: int
2713: sshpkt_get_end(struct ssh *ssh)
2714: {
2715: if (sshbuf_len(ssh->state->incoming_packet) > 0)
2716: return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2717: return 0;
2718: }
2719:
2720: const u_char *
2721: sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2722: {
2723: if (lenp != NULL)
2724: *lenp = sshbuf_len(ssh->state->incoming_packet);
2725: return sshbuf_ptr(ssh->state->incoming_packet);
2726: }
2727:
2728: /* start a new packet */
2729:
2730: int
2731: sshpkt_start(struct ssh *ssh, u_char type)
2732: {
1.249 ! djm 2733: u_char buf[6]; /* u32 packet length, u8 pad len, u8 type */
1.201 markus 2734:
2735: DBG(debug("packet_start[%d]", type));
1.249 ! djm 2736: memset(buf, 0, sizeof(buf));
! 2737: buf[sizeof(buf) - 1] = type;
1.201 markus 2738: sshbuf_reset(ssh->state->outgoing_packet);
1.249 ! djm 2739: return sshbuf_put(ssh->state->outgoing_packet, buf, sizeof(buf));
1.201 markus 2740: }
2741:
1.242 markus 2742: static int
2743: ssh_packet_send_mux(struct ssh *ssh)
2744: {
2745: struct session_state *state = ssh->state;
2746: u_char type, *cp;
2747: size_t len;
2748: int r;
2749:
2750: if (ssh->kex)
2751: return SSH_ERR_INTERNAL_ERROR;
2752: len = sshbuf_len(state->outgoing_packet);
2753: if (len < 6)
2754: return SSH_ERR_INTERNAL_ERROR;
2755: cp = sshbuf_mutable_ptr(state->outgoing_packet);
2756: type = cp[5];
2757: if (ssh_packet_log_type(type))
2758: debug3("%s: type %u", __func__, type);
2759: /* drop everything, but the connection protocol */
2760: if (type >= SSH2_MSG_CONNECTION_MIN &&
2761: type <= SSH2_MSG_CONNECTION_MAX) {
2762: POKE_U32(cp, len - 4);
2763: if ((r = sshbuf_putb(state->output,
2764: state->outgoing_packet)) != 0)
2765: return r;
2766: /* sshbuf_dump(state->output, stderr); */
2767: }
2768: sshbuf_reset(state->outgoing_packet);
2769: return 0;
2770: }
2771:
1.201 markus 2772: /* send it */
2773:
2774: int
2775: sshpkt_send(struct ssh *ssh)
2776: {
1.242 markus 2777: if (ssh->state && ssh->state->mux)
2778: return ssh_packet_send_mux(ssh);
1.249 ! djm 2779: return ssh_packet_send2(ssh);
1.201 markus 2780: }
2781:
2782: int
2783: sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2784: {
2785: char buf[1024];
2786: va_list args;
2787: int r;
2788:
2789: va_start(args, fmt);
2790: vsnprintf(buf, sizeof(buf), fmt, args);
2791: va_end(args);
2792:
1.249 ! djm 2793: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
! 2794: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
! 2795: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
! 2796: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
! 2797: (r = sshpkt_send(ssh)) != 0)
! 2798: return r;
1.201 markus 2799: return 0;
2800: }
2801:
2802: /* roundup current message to pad bytes */
2803: int
2804: sshpkt_add_padding(struct ssh *ssh, u_char pad)
2805: {
2806: ssh->state->extra_pad = pad;
2807: return 0;
1.1 deraadt 2808: }
![[BACK]](/icons/back.gif){kind=icon}
Return to packet.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh