Annotation of src/usr.bin/ssh/packet.c, Revision 1.49
1.1 deraadt 1: /*
1.15 deraadt 2: * Author: Tatu Ylonen <ylo@cs.hut.fi>
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
1.35 deraadt 5: * This file contains code implementing the packet protocol and communication
6: * with the other side. This same code is used both on client and server side.
1.29 markus 7: *
1.35 deraadt 8: * As far as I am concerned, the code I have written for this software
9: * can be used freely for any purpose. Any derived versions of this
10: * software must be clearly marked as such, and if the derived work is
11: * incompatible with the protocol description in the RFC file, it must be
12: * called by a name other than "ssh" or "Secure Shell".
1.29 markus 13: *
1.25 markus 14: *
15: * SSH2 packet format added by Markus Friedl.
1.35 deraadt 16: * Copyright (c) 2000 Markus Friedl. All rights reserved.
1.25 markus 17: *
1.35 deraadt 18: * Redistribution and use in source and binary forms, with or without
19: * modification, are permitted provided that the following conditions
20: * are met:
21: * 1. Redistributions of source code must retain the above copyright
22: * notice, this list of conditions and the following disclaimer.
23: * 2. Redistributions in binary form must reproduce the above copyright
24: * notice, this list of conditions and the following disclaimer in the
25: * documentation and/or other materials provided with the distribution.
26: *
27: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
28: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
29: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
30: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
31: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
32: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.15 deraadt 37: */
1.1 deraadt 38:
39: #include "includes.h"
1.49 ! itojun 40: RCSID("$OpenBSD: packet.c,v 1.48 2001/02/04 15:32:24 stevesk Exp $");
1.1 deraadt 41:
42: #include "xmalloc.h"
43: #include "buffer.h"
44: #include "packet.h"
45: #include "bufaux.h"
46: #include "crc32.h"
47: #include "getput.h"
48:
49: #include "compress.h"
1.9 dugsong 50: #include "deattack.h"
1.23 markus 51: #include "channels.h"
1.1 deraadt 52:
1.25 markus 53: #include "compat.h"
1.45 markus 54: #include "ssh1.h"
1.25 markus 55: #include "ssh2.h"
56:
1.27 markus 57: #include <openssl/bn.h>
58: #include <openssl/dh.h>
59: #include <openssl/hmac.h>
1.37 markus 60: #include "cipher.h"
1.25 markus 61: #include "kex.h"
62: #include "hmac.h"
1.46 markus 63: #include "log.h"
64: #include "canohost.h"
1.25 markus 65:
66: #ifdef PACKET_DEBUG
67: #define DBG(x) x
68: #else
69: #define DBG(x)
70: #endif
71:
1.16 markus 72: /*
73: * This variable contains the file descriptors used for communicating with
74: * the other side. connection_in is used for reading; connection_out for
75: * writing. These can be the same descriptor, in which case it is assumed to
76: * be a socket.
77: */
1.1 deraadt 78: static int connection_in = -1;
79: static int connection_out = -1;
80:
1.16 markus 81: /*
82: * Cipher type. This value is only used to determine whether to pad the
83: * packets with zeroes or random data.
84: */
1.1 deraadt 85: static int cipher_type = SSH_CIPHER_NONE;
86:
87: /* Protocol flags for the remote side. */
1.40 markus 88: static u_int remote_protocol_flags = 0;
1.1 deraadt 89:
90: /* Encryption context for receiving data. This is only used for decryption. */
91: static CipherContext receive_context;
1.14 markus 92:
93: /* Encryption context for sending data. This is only used for encryption. */
1.1 deraadt 94: static CipherContext send_context;
95:
96: /* Buffer for raw input data from the socket. */
97: static Buffer input;
98:
99: /* Buffer for raw output data going to the socket. */
100: static Buffer output;
101:
102: /* Buffer for the partial outgoing packet being constructed. */
103: static Buffer outgoing_packet;
104:
105: /* Buffer for the incoming packet currently being processed. */
106: static Buffer incoming_packet;
107:
108: /* Scratch buffer for packet compression/decompression. */
109: static Buffer compression_buffer;
110:
111: /* Flag indicating whether packet compression/decompression is enabled. */
112: static int packet_compression = 0;
113:
1.12 markus 114: /* default maximum packet size */
115: int max_packet_size = 32768;
116:
1.1 deraadt 117: /* Flag indicating whether this module has been initialized. */
118: static int initialized = 0;
119:
120: /* Set to true if the connection is interactive. */
121: static int interactive_mode = 0;
122:
1.25 markus 123: /* True if SSH2 packet format is used */
124: int use_ssh2_packet_format = 0;
125:
126: /* Session key information for Encryption and MAC */
127: Kex *kex = NULL;
128:
129: void
130: packet_set_kex(Kex *k)
131: {
132: if( k->mac[MODE_IN ].key == NULL ||
133: k->enc[MODE_IN ].key == NULL ||
134: k->enc[MODE_IN ].iv == NULL ||
135: k->mac[MODE_OUT].key == NULL ||
136: k->enc[MODE_OUT].key == NULL ||
137: k->enc[MODE_OUT].iv == NULL)
138: fatal("bad KEX");
139: kex = k;
140: }
141: void
142: clear_enc_keys(Enc *enc, int len)
143: {
144: memset(enc->iv, 0, len);
145: memset(enc->key, 0, len);
146: xfree(enc->iv);
147: xfree(enc->key);
148: enc->iv = NULL;
149: enc->key = NULL;
150: }
151: void
152: packet_set_ssh2_format(void)
153: {
1.31 markus 154: DBG(debug("use_ssh2_packet_format"));
1.25 markus 155: use_ssh2_packet_format = 1;
156: }
157:
1.16 markus 158: /*
159: * Sets the descriptors used for communication. Disables encryption until
160: * packet_set_encryption_key is called.
161: */
1.2 provos 162: void
163: packet_set_connection(int fd_in, int fd_out)
1.1 deraadt 164: {
1.37 markus 165: Cipher *none = cipher_by_name("none");
166: if (none == NULL)
167: fatal("packet_set_connection: cannot load cipher 'none'");
1.14 markus 168: connection_in = fd_in;
169: connection_out = fd_out;
170: cipher_type = SSH_CIPHER_NONE;
1.40 markus 171: cipher_init(&send_context, none, (u_char *) "", 0, NULL, 0);
172: cipher_init(&receive_context, none, (u_char *) "", 0, NULL, 0);
1.14 markus 173: if (!initialized) {
174: initialized = 1;
175: buffer_init(&input);
176: buffer_init(&output);
177: buffer_init(&outgoing_packet);
178: buffer_init(&incoming_packet);
179: }
180: /* Kludge: arrange the close function to be called from fatal(). */
181: fatal_add_cleanup((void (*) (void *)) packet_close, NULL);
1.1 deraadt 182: }
183:
1.19 markus 184: /* Returns 1 if remote host is connected via socket, 0 if not. */
185:
186: int
187: packet_connection_is_on_socket()
188: {
189: struct sockaddr_storage from, to;
190: socklen_t fromlen, tolen;
191:
192: /* filedescriptors in and out are the same, so it's a socket */
193: if (connection_in == connection_out)
194: return 1;
195: fromlen = sizeof(from);
196: memset(&from, 0, sizeof(from));
1.20 markus 197: if (getpeername(connection_in, (struct sockaddr *)&from, &fromlen) < 0)
1.19 markus 198: return 0;
199: tolen = sizeof(to);
200: memset(&to, 0, sizeof(to));
1.20 markus 201: if (getpeername(connection_out, (struct sockaddr *)&to, &tolen) < 0)
1.19 markus 202: return 0;
203: if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
204: return 0;
205: if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
206: return 0;
207: return 1;
208: }
209:
210: /* returns 1 if connection is via ipv4 */
211:
212: int
213: packet_connection_is_ipv4()
214: {
215: struct sockaddr_storage to;
1.21 deraadt 216: socklen_t tolen = sizeof(to);
1.19 markus 217:
218: memset(&to, 0, sizeof(to));
219: if (getsockname(connection_out, (struct sockaddr *)&to, &tolen) < 0)
220: return 0;
221: if (to.ss_family != AF_INET)
222: return 0;
223: return 1;
224: }
225:
1.1 deraadt 226: /* Sets the connection into non-blocking mode. */
227:
1.2 provos 228: void
229: packet_set_nonblocking()
1.1 deraadt 230: {
1.14 markus 231: /* Set the socket into non-blocking mode. */
232: if (fcntl(connection_in, F_SETFL, O_NONBLOCK) < 0)
233: error("fcntl O_NONBLOCK: %.100s", strerror(errno));
234:
235: if (connection_out != connection_in) {
236: if (fcntl(connection_out, F_SETFL, O_NONBLOCK) < 0)
237: error("fcntl O_NONBLOCK: %.100s", strerror(errno));
238: }
1.1 deraadt 239: }
240:
241: /* Returns the socket used for reading. */
242:
1.2 provos 243: int
244: packet_get_connection_in()
1.1 deraadt 245: {
1.14 markus 246: return connection_in;
1.1 deraadt 247: }
248:
249: /* Returns the descriptor used for writing. */
250:
1.2 provos 251: int
252: packet_get_connection_out()
1.1 deraadt 253: {
1.14 markus 254: return connection_out;
1.1 deraadt 255: }
256:
257: /* Closes the connection and clears and frees internal data structures. */
258:
1.2 provos 259: void
260: packet_close()
1.1 deraadt 261: {
1.14 markus 262: if (!initialized)
263: return;
264: initialized = 0;
265: if (connection_in == connection_out) {
266: shutdown(connection_out, SHUT_RDWR);
267: close(connection_out);
268: } else {
269: close(connection_in);
270: close(connection_out);
271: }
272: buffer_free(&input);
273: buffer_free(&output);
274: buffer_free(&outgoing_packet);
275: buffer_free(&incoming_packet);
276: if (packet_compression) {
277: buffer_free(&compression_buffer);
278: buffer_compress_uninit();
279: }
1.1 deraadt 280: }
281:
282: /* Sets remote side protocol flags. */
283:
1.2 provos 284: void
1.40 markus 285: packet_set_protocol_flags(u_int protocol_flags)
1.1 deraadt 286: {
1.14 markus 287: remote_protocol_flags = protocol_flags;
288: channel_set_options((protocol_flags & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) != 0);
1.1 deraadt 289: }
290:
291: /* Returns the remote protocol flags set earlier by the above function. */
292:
1.40 markus 293: u_int
1.2 provos 294: packet_get_protocol_flags()
1.1 deraadt 295: {
1.14 markus 296: return remote_protocol_flags;
1.1 deraadt 297: }
298:
1.16 markus 299: /*
300: * Starts packet compression from the next packet on in both directions.
301: * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
302: */
1.1 deraadt 303:
1.25 markus 304: /*** XXXXX todo: kex means re-init */
1.2 provos 305: void
306: packet_start_compression(int level)
1.1 deraadt 307: {
1.14 markus 308: if (packet_compression)
309: fatal("Compression already enabled.");
310: packet_compression = 1;
311: buffer_init(&compression_buffer);
312: buffer_compress_init(level);
1.1 deraadt 313: }
314:
1.16 markus 315: /*
316: * Encrypts the given number of bytes, copying from src to dest. bytes is
317: * known to be a multiple of 8.
318: */
1.1 deraadt 319:
1.2 provos 320: void
1.14 markus 321: packet_encrypt(CipherContext * cc, void *dest, void *src,
1.40 markus 322: u_int bytes)
1.1 deraadt 323: {
1.14 markus 324: cipher_encrypt(cc, dest, src, bytes);
1.1 deraadt 325: }
326:
1.16 markus 327: /*
328: * Decrypts the given number of bytes, copying from src to dest. bytes is
329: * known to be a multiple of 8.
330: */
1.1 deraadt 331:
1.2 provos 332: void
1.40 markus 333: packet_decrypt(CipherContext *context, void *dest, void *src, u_int bytes)
1.1 deraadt 334: {
1.16 markus 335: /*
336: * Cryptographic attack detector for ssh - Modifications for packet.c
337: * (C)1998 CORE-SDI, Buenos Aires Argentina Ariel Futoransky(futo@core-sdi.com)
338: */
1.37 markus 339: if (!compat20 &&
340: context->cipher->number != SSH_CIPHER_NONE &&
341: detect_attack(src, bytes, NULL) == DEATTACK_DETECTED)
1.14 markus 342: packet_disconnect("crc32 compensation attack: network attack detected");
343:
1.37 markus 344: cipher_decrypt(context, dest, src, bytes);
1.1 deraadt 345: }
346:
1.16 markus 347: /*
348: * Causes any further packets to be encrypted using the given key. The same
349: * key is used for both sending and reception. However, both directions are
350: * encrypted independently of each other.
351: */
1.1 deraadt 352:
1.2 provos 353: void
1.40 markus 354: packet_set_encryption_key(const u_char *key, u_int keylen,
1.37 markus 355: int number)
1.1 deraadt 356: {
1.37 markus 357: Cipher *cipher = cipher_by_number(number);
358: if (cipher == NULL)
359: fatal("packet_set_encryption_key: unknown cipher number %d", number);
1.25 markus 360: if (keylen < 20)
1.37 markus 361: fatal("packet_set_encryption_key: keylen too small: %d", keylen);
362: cipher_init(&receive_context, cipher, key, keylen, NULL, 0);
363: cipher_init(&send_context, cipher, key, keylen, NULL, 0);
1.1 deraadt 364: }
365:
366: /* Starts constructing a packet to send. */
367:
1.2 provos 368: void
1.25 markus 369: packet_start1(int type)
1.1 deraadt 370: {
1.14 markus 371: char buf[9];
1.1 deraadt 372:
1.14 markus 373: buffer_clear(&outgoing_packet);
374: memset(buf, 0, 8);
375: buf[8] = type;
376: buffer_append(&outgoing_packet, buf, 9);
1.1 deraadt 377: }
378:
1.25 markus 379: void
380: packet_start2(int type)
381: {
382: char buf[4+1+1];
383:
384: buffer_clear(&outgoing_packet);
385: memset(buf, 0, sizeof buf);
386: /* buf[0..3] = payload_len; */
387: /* buf[4] = pad_len; */
388: buf[5] = type & 0xff;
389: buffer_append(&outgoing_packet, buf, sizeof buf);
390: }
391:
392: void
393: packet_start(int type)
394: {
395: DBG(debug("packet_start[%d]",type));
396: if (use_ssh2_packet_format)
397: packet_start2(type);
398: else
399: packet_start1(type);
400: }
401:
1.1 deraadt 402: /* Appends a character to the packet data. */
403:
1.2 provos 404: void
405: packet_put_char(int value)
1.1 deraadt 406: {
1.14 markus 407: char ch = value;
408: buffer_append(&outgoing_packet, &ch, 1);
1.1 deraadt 409: }
410:
411: /* Appends an integer to the packet data. */
412:
1.2 provos 413: void
1.40 markus 414: packet_put_int(u_int value)
1.1 deraadt 415: {
1.14 markus 416: buffer_put_int(&outgoing_packet, value);
1.1 deraadt 417: }
418:
419: /* Appends a string to packet data. */
420:
1.2 provos 421: void
1.40 markus 422: packet_put_string(const char *buf, u_int len)
1.1 deraadt 423: {
1.14 markus 424: buffer_put_string(&outgoing_packet, buf, len);
1.1 deraadt 425: }
1.24 markus 426: void
427: packet_put_cstring(const char *str)
428: {
429: buffer_put_string(&outgoing_packet, str, strlen(str));
430: }
431:
432: void
1.40 markus 433: packet_put_raw(const char *buf, u_int len)
1.24 markus 434: {
435: buffer_append(&outgoing_packet, buf, len);
436: }
437:
1.1 deraadt 438:
439: /* Appends an arbitrary precision integer to packet data. */
440:
1.2 provos 441: void
1.14 markus 442: packet_put_bignum(BIGNUM * value)
1.1 deraadt 443: {
1.14 markus 444: buffer_put_bignum(&outgoing_packet, value);
1.1 deraadt 445: }
1.24 markus 446: void
447: packet_put_bignum2(BIGNUM * value)
448: {
449: buffer_put_bignum2(&outgoing_packet, value);
450: }
1.1 deraadt 451:
1.16 markus 452: /*
453: * Finalizes and sends the packet. If the encryption key has been set,
454: * encrypts the packet before sending.
455: */
1.14 markus 456:
1.2 provos 457: void
1.49 ! itojun 458: packet_send1(void)
1.1 deraadt 459: {
1.14 markus 460: char buf[8], *cp;
461: int i, padding, len;
1.40 markus 462: u_int checksum;
1.14 markus 463: u_int32_t rand = 0;
464:
1.16 markus 465: /*
466: * If using packet compression, compress the payload of the outgoing
467: * packet.
468: */
1.14 markus 469: if (packet_compression) {
470: buffer_clear(&compression_buffer);
471: /* Skip padding. */
472: buffer_consume(&outgoing_packet, 8);
473: /* padding */
474: buffer_append(&compression_buffer, "\0\0\0\0\0\0\0\0", 8);
475: buffer_compress(&outgoing_packet, &compression_buffer);
476: buffer_clear(&outgoing_packet);
477: buffer_append(&outgoing_packet, buffer_ptr(&compression_buffer),
478: buffer_len(&compression_buffer));
479: }
480: /* Compute packet length without padding (add checksum, remove padding). */
481: len = buffer_len(&outgoing_packet) + 4 - 8;
482:
1.32 markus 483: /* Insert padding. Initialized to zero in packet_start1() */
1.14 markus 484: padding = 8 - len % 8;
485: if (cipher_type != SSH_CIPHER_NONE) {
486: cp = buffer_ptr(&outgoing_packet);
487: for (i = 0; i < padding; i++) {
488: if (i % 4 == 0)
489: rand = arc4random();
490: cp[7 - i] = rand & 0xff;
491: rand >>= 8;
492: }
493: }
494: buffer_consume(&outgoing_packet, 8 - padding);
495:
496: /* Add check bytes. */
1.40 markus 497: checksum = ssh_crc32((u_char *) buffer_ptr(&outgoing_packet),
1.34 deraadt 498: buffer_len(&outgoing_packet));
1.14 markus 499: PUT_32BIT(buf, checksum);
500: buffer_append(&outgoing_packet, buf, 4);
1.1 deraadt 501:
502: #ifdef PACKET_DEBUG
1.14 markus 503: fprintf(stderr, "packet_send plain: ");
504: buffer_dump(&outgoing_packet);
1.1 deraadt 505: #endif
506:
1.14 markus 507: /* Append to output. */
508: PUT_32BIT(buf, len);
509: buffer_append(&output, buf, 4);
510: buffer_append_space(&output, &cp, buffer_len(&outgoing_packet));
511: packet_encrypt(&send_context, cp, buffer_ptr(&outgoing_packet),
512: buffer_len(&outgoing_packet));
513:
1.1 deraadt 514: #ifdef PACKET_DEBUG
1.14 markus 515: fprintf(stderr, "encrypted: ");
516: buffer_dump(&output);
1.1 deraadt 517: #endif
518:
1.14 markus 519: buffer_clear(&outgoing_packet);
1.1 deraadt 520:
1.16 markus 521: /*
522: * Note that the packet is now only buffered in output. It won\'t be
523: * actually sent until packet_write_wait or packet_write_poll is
524: * called.
525: */
1.1 deraadt 526: }
527:
1.16 markus 528: /*
1.25 markus 529: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
530: */
531: void
1.49 ! itojun 532: packet_send2(void)
1.25 markus 533: {
1.40 markus 534: u_char *macbuf = NULL;
1.25 markus 535: char *cp;
1.40 markus 536: u_int packet_length = 0;
537: u_int i, padlen, len;
1.25 markus 538: u_int32_t rand = 0;
1.40 markus 539: static u_int seqnr = 0;
1.25 markus 540: int type;
541: Enc *enc = NULL;
542: Mac *mac = NULL;
543: Comp *comp = NULL;
544: int block_size;
545:
546: if (kex != NULL) {
547: enc = &kex->enc[MODE_OUT];
548: mac = &kex->mac[MODE_OUT];
549: comp = &kex->comp[MODE_OUT];
550: }
1.37 markus 551: block_size = enc ? enc->cipher->block_size : 8;
1.25 markus 552:
553: cp = buffer_ptr(&outgoing_packet);
554: type = cp[5] & 0xff;
555:
556: #ifdef PACKET_DEBUG
557: fprintf(stderr, "plain: ");
558: buffer_dump(&outgoing_packet);
559: #endif
560:
561: if (comp && comp->enabled) {
562: len = buffer_len(&outgoing_packet);
563: /* skip header, compress only payload */
564: buffer_consume(&outgoing_packet, 5);
565: buffer_clear(&compression_buffer);
566: buffer_compress(&outgoing_packet, &compression_buffer);
567: buffer_clear(&outgoing_packet);
568: buffer_append(&outgoing_packet, "\0\0\0\0\0", 5);
569: buffer_append(&outgoing_packet, buffer_ptr(&compression_buffer),
570: buffer_len(&compression_buffer));
571: DBG(debug("compression: raw %d compressed %d", len,
572: buffer_len(&outgoing_packet)));
573: }
574:
575: /* sizeof (packet_len + pad_len + payload) */
576: len = buffer_len(&outgoing_packet);
577:
578: /*
579: * calc size of padding, alloc space, get random data,
580: * minimum padding is 4 bytes
581: */
582: padlen = block_size - (len % block_size);
583: if (padlen < 4)
584: padlen += block_size;
585: buffer_append_space(&outgoing_packet, &cp, padlen);
1.38 markus 586: if (enc && enc->cipher->number != SSH_CIPHER_NONE) {
1.32 markus 587: /* random padding */
1.25 markus 588: for (i = 0; i < padlen; i++) {
589: if (i % 4 == 0)
590: rand = arc4random();
591: cp[i] = rand & 0xff;
592: rand <<= 8;
593: }
1.32 markus 594: } else {
595: /* clear padding */
596: memset(cp, 0, padlen);
1.25 markus 597: }
598: /* packet_length includes payload, padding and padding length field */
599: packet_length = buffer_len(&outgoing_packet) - 4;
600: cp = buffer_ptr(&outgoing_packet);
601: PUT_32BIT(cp, packet_length);
602: cp[4] = padlen & 0xff;
603: DBG(debug("send: len %d (includes padlen %d)", packet_length+4, padlen));
604:
605: /* compute MAC over seqnr and packet(length fields, payload, padding) */
606: if (mac && mac->enabled) {
607: macbuf = hmac( mac->md, seqnr,
1.40 markus 608: (u_char *) buffer_ptr(&outgoing_packet),
1.25 markus 609: buffer_len(&outgoing_packet),
610: mac->key, mac->key_len
611: );
1.36 markus 612: DBG(debug("done calc MAC out #%d", seqnr));
1.25 markus 613: }
614: /* encrypt packet and append to output buffer. */
615: buffer_append_space(&output, &cp, buffer_len(&outgoing_packet));
616: packet_encrypt(&send_context, cp, buffer_ptr(&outgoing_packet),
617: buffer_len(&outgoing_packet));
618: /* append unencrypted MAC */
619: if (mac && mac->enabled)
620: buffer_append(&output, (char *)macbuf, mac->mac_len);
621: #ifdef PACKET_DEBUG
622: fprintf(stderr, "encrypted: ");
623: buffer_dump(&output);
624: #endif
1.29 markus 625: /* increment sequence number for outgoing packets */
626: if (++seqnr == 0)
627: log("outgoing seqnr wraps around");
1.25 markus 628: buffer_clear(&outgoing_packet);
629:
630: if (type == SSH2_MSG_NEWKEYS) {
631: if (kex==NULL || mac==NULL || enc==NULL || comp==NULL)
632: fatal("packet_send2: no KEX");
633: if (mac->md != NULL)
634: mac->enabled = 1;
1.37 markus 635: DBG(debug("cipher_init send_context"));
636: cipher_init(&send_context, enc->cipher,
637: enc->key, enc->cipher->key_len,
638: enc->iv, enc->cipher->block_size);
1.25 markus 639: clear_enc_keys(enc, kex->we_need);
640: if (comp->type != 0 && comp->enabled == 0) {
641: comp->enabled = 1;
642: if (! packet_compression)
643: packet_start_compression(6);
644: }
645: }
646: }
647:
648: void
649: packet_send()
650: {
651: if (use_ssh2_packet_format)
652: packet_send2();
653: else
654: packet_send1();
655: DBG(debug("packet_send done"));
656: }
657:
658: /*
1.16 markus 659: * Waits until a packet has been received, and returns its type. Note that
660: * no other data is processed until this returns, so this function should not
661: * be used during the interactive session.
662: */
1.1 deraadt 663:
1.2 provos 664: int
665: packet_read(int *payload_len_ptr)
1.1 deraadt 666: {
1.14 markus 667: int type, len;
668: fd_set set;
669: char buf[8192];
1.25 markus 670: DBG(debug("packet_read()"));
1.14 markus 671:
672: /* Since we are blocking, ensure that all written packets have been sent. */
673: packet_write_wait();
674:
675: /* Stay in the loop until we have received a complete packet. */
676: for (;;) {
677: /* Try to read a packet from the buffer. */
678: type = packet_read_poll(payload_len_ptr);
1.32 markus 679: if (!use_ssh2_packet_format && (
680: type == SSH_SMSG_SUCCESS
1.14 markus 681: || type == SSH_SMSG_FAILURE
682: || type == SSH_CMSG_EOF
1.32 markus 683: || type == SSH_CMSG_EXIT_CONFIRMATION))
1.14 markus 684: packet_integrity_check(*payload_len_ptr, 0, type);
685: /* If we got a packet, return it. */
686: if (type != SSH_MSG_NONE)
687: return type;
1.16 markus 688: /*
689: * Otherwise, wait for some data to arrive, add it to the
690: * buffer, and try again.
691: */
1.14 markus 692: FD_ZERO(&set);
693: FD_SET(connection_in, &set);
1.16 markus 694:
1.14 markus 695: /* Wait for some data to arrive. */
696: select(connection_in + 1, &set, NULL, NULL, NULL);
1.16 markus 697:
1.14 markus 698: /* Read data from the socket. */
699: len = read(connection_in, buf, sizeof(buf));
1.18 markus 700: if (len == 0) {
701: log("Connection closed by %.200s", get_remote_ipaddr());
702: fatal_cleanup();
703: }
1.14 markus 704: if (len < 0)
705: fatal("Read from socket failed: %.100s", strerror(errno));
706: /* Append it to the buffer. */
707: packet_process_incoming(buf, len);
708: }
709: /* NOTREACHED */
1.1 deraadt 710: }
711:
1.16 markus 712: /*
713: * Waits until a packet has been received, verifies that its type matches
714: * that given, and gives a fatal error and exits if there is a mismatch.
715: */
1.1 deraadt 716:
1.2 provos 717: void
718: packet_read_expect(int *payload_len_ptr, int expected_type)
1.1 deraadt 719: {
1.14 markus 720: int type;
1.1 deraadt 721:
1.14 markus 722: type = packet_read(payload_len_ptr);
723: if (type != expected_type)
724: packet_disconnect("Protocol error: expected packet type %d, got %d",
1.25 markus 725: expected_type, type);
1.1 deraadt 726: }
727:
728: /* Checks if a full packet is available in the data received so far via
1.14 markus 729: * packet_process_incoming. If so, reads the packet; otherwise returns
730: * SSH_MSG_NONE. This does not wait for data from the connection.
731: *
732: * SSH_MSG_DISCONNECT is handled specially here. Also,
733: * SSH_MSG_IGNORE messages are skipped by this function and are never returned
734: * to higher levels.
735: *
736: * The returned payload_len does include space consumed by:
737: * Packet length
738: * Padding
739: * Packet type
740: * Check bytes
741: */
1.1 deraadt 742:
1.2 provos 743: int
1.25 markus 744: packet_read_poll1(int *payload_len_ptr)
1.1 deraadt 745: {
1.40 markus 746: u_int len, padded_len;
747: u_char *ucp;
1.25 markus 748: char buf[8], *cp;
1.40 markus 749: u_int checksum, stored_checksum;
1.14 markus 750:
751: /* Check if input size is less than minimum packet size. */
752: if (buffer_len(&input) < 4 + 8)
753: return SSH_MSG_NONE;
754: /* Get length of incoming packet. */
1.40 markus 755: ucp = (u_char *) buffer_ptr(&input);
1.14 markus 756: len = GET_32BIT(ucp);
757: if (len < 1 + 2 + 2 || len > 256 * 1024)
758: packet_disconnect("Bad packet length %d.", len);
759: padded_len = (len + 8) & ~7;
760:
761: /* Check if the packet has been entirely received. */
762: if (buffer_len(&input) < 4 + padded_len)
763: return SSH_MSG_NONE;
764:
765: /* The entire packet is in buffer. */
766:
767: /* Consume packet length. */
768: buffer_consume(&input, 4);
769:
770: /* Copy data to incoming_packet. */
771: buffer_clear(&incoming_packet);
772: buffer_append_space(&incoming_packet, &cp, padded_len);
773: packet_decrypt(&receive_context, cp, buffer_ptr(&input), padded_len);
774: buffer_consume(&input, padded_len);
1.1 deraadt 775:
776: #ifdef PACKET_DEBUG
1.14 markus 777: fprintf(stderr, "read_poll plain: ");
778: buffer_dump(&incoming_packet);
1.1 deraadt 779: #endif
780:
1.14 markus 781: /* Compute packet checksum. */
1.40 markus 782: checksum = ssh_crc32((u_char *) buffer_ptr(&incoming_packet),
1.25 markus 783: buffer_len(&incoming_packet) - 4);
1.14 markus 784:
785: /* Skip padding. */
786: buffer_consume(&incoming_packet, 8 - len % 8);
787:
788: /* Test check bytes. */
789:
790: if (len != buffer_len(&incoming_packet))
791: packet_disconnect("packet_read_poll: len %d != buffer_len %d.",
1.25 markus 792: len, buffer_len(&incoming_packet));
1.14 markus 793:
1.40 markus 794: ucp = (u_char *) buffer_ptr(&incoming_packet) + len - 4;
1.14 markus 795: stored_checksum = GET_32BIT(ucp);
796: if (checksum != stored_checksum)
797: packet_disconnect("Corrupted check bytes on input.");
798: buffer_consume_end(&incoming_packet, 4);
799:
800: /* If using packet compression, decompress the packet. */
801: if (packet_compression) {
802: buffer_clear(&compression_buffer);
803: buffer_uncompress(&incoming_packet, &compression_buffer);
804: buffer_clear(&incoming_packet);
805: buffer_append(&incoming_packet, buffer_ptr(&compression_buffer),
1.25 markus 806: buffer_len(&compression_buffer));
1.14 markus 807: }
808: /* Get packet type. */
809: buffer_get(&incoming_packet, &buf[0], 1);
810:
811: /* Return length of payload (without type field). */
812: *payload_len_ptr = buffer_len(&incoming_packet);
813:
814: /* Return type. */
1.40 markus 815: return (u_char) buf[0];
1.1 deraadt 816: }
1.14 markus 817:
1.25 markus 818: int
819: packet_read_poll2(int *payload_len_ptr)
820: {
1.40 markus 821: u_int padlen, need;
822: u_char buf[8], *macbuf;
823: u_char *ucp;
1.25 markus 824: char *cp;
1.40 markus 825: static u_int packet_length = 0;
826: static u_int seqnr = 0;
1.25 markus 827: int type;
828: int maclen, block_size;
829: Enc *enc = NULL;
830: Mac *mac = NULL;
831: Comp *comp = NULL;
832:
833: if (kex != NULL) {
834: enc = &kex->enc[MODE_IN];
835: mac = &kex->mac[MODE_IN];
836: comp = &kex->comp[MODE_IN];
837: }
838: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.37 markus 839: block_size = enc ? enc->cipher->block_size : 8;
1.25 markus 840:
841: if (packet_length == 0) {
842: /*
843: * check if input size is less than the cipher block size,
844: * decrypt first block and extract length of incoming packet
845: */
846: if (buffer_len(&input) < block_size)
847: return SSH_MSG_NONE;
848: buffer_clear(&incoming_packet);
849: buffer_append_space(&incoming_packet, &cp, block_size);
850: packet_decrypt(&receive_context, cp, buffer_ptr(&input),
851: block_size);
1.40 markus 852: ucp = (u_char *) buffer_ptr(&incoming_packet);
1.25 markus 853: packet_length = GET_32BIT(ucp);
854: if (packet_length < 1 + 4 || packet_length > 256 * 1024) {
855: buffer_dump(&incoming_packet);
856: packet_disconnect("Bad packet length %d.", packet_length);
857: }
858: DBG(debug("input: packet len %d", packet_length+4));
859: buffer_consume(&input, block_size);
860: }
861: /* we have a partial packet of block_size bytes */
862: need = 4 + packet_length - block_size;
863: DBG(debug("partial packet %d, need %d, maclen %d", block_size,
864: need, maclen));
865: if (need % block_size != 0)
866: fatal("padding error: need %d block %d mod %d",
867: need, block_size, need % block_size);
868: /*
869: * check if the entire packet has been received and
870: * decrypt into incoming_packet
871: */
872: if (buffer_len(&input) < need + maclen)
873: return SSH_MSG_NONE;
874: #ifdef PACKET_DEBUG
875: fprintf(stderr, "read_poll enc/full: ");
876: buffer_dump(&input);
877: #endif
878: buffer_append_space(&incoming_packet, &cp, need);
879: packet_decrypt(&receive_context, cp, buffer_ptr(&input), need);
880: buffer_consume(&input, need);
881: /*
882: * compute MAC over seqnr and packet,
883: * increment sequence number for incoming packet
884: */
1.29 markus 885: if (mac && mac->enabled) {
1.25 markus 886: macbuf = hmac( mac->md, seqnr,
1.40 markus 887: (u_char *) buffer_ptr(&incoming_packet),
1.25 markus 888: buffer_len(&incoming_packet),
889: mac->key, mac->key_len
890: );
891: if (memcmp(macbuf, buffer_ptr(&input), mac->mac_len) != 0)
1.36 markus 892: packet_disconnect("Corrupted MAC on input.");
893: DBG(debug("MAC #%d ok", seqnr));
1.25 markus 894: buffer_consume(&input, mac->mac_len);
895: }
1.29 markus 896: if (++seqnr == 0)
897: log("incoming seqnr wraps around");
1.25 markus 898:
899: /* get padlen */
900: cp = buffer_ptr(&incoming_packet) + 4;
901: padlen = *cp & 0xff;
902: DBG(debug("input: padlen %d", padlen));
903: if (padlen < 4)
904: packet_disconnect("Corrupted padlen %d on input.", padlen);
905:
906: /* skip packet size + padlen, discard padding */
907: buffer_consume(&incoming_packet, 4 + 1);
908: buffer_consume_end(&incoming_packet, padlen);
909:
910: DBG(debug("input: len before de-compress %d", buffer_len(&incoming_packet)));
911: if (comp && comp->enabled) {
912: buffer_clear(&compression_buffer);
913: buffer_uncompress(&incoming_packet, &compression_buffer);
914: buffer_clear(&incoming_packet);
915: buffer_append(&incoming_packet, buffer_ptr(&compression_buffer),
916: buffer_len(&compression_buffer));
917: DBG(debug("input: len after de-compress %d", buffer_len(&incoming_packet)));
918: }
919: /*
920: * get packet type, implies consume.
921: * return length of payload (without type field)
922: */
923: buffer_get(&incoming_packet, (char *)&buf[0], 1);
924: *payload_len_ptr = buffer_len(&incoming_packet);
925:
926: /* reset for next packet */
927: packet_length = 0;
928:
929: /* extract packet type */
1.40 markus 930: type = (u_char)buf[0];
1.25 markus 931:
932: if (type == SSH2_MSG_NEWKEYS) {
933: if (kex==NULL || mac==NULL || enc==NULL || comp==NULL)
934: fatal("packet_read_poll2: no KEX");
935: if (mac->md != NULL)
936: mac->enabled = 1;
1.37 markus 937: DBG(debug("cipher_init receive_context"));
938: cipher_init(&receive_context, enc->cipher,
939: enc->key, enc->cipher->key_len,
940: enc->iv, enc->cipher->block_size);
1.25 markus 941: clear_enc_keys(enc, kex->we_need);
942: if (comp->type != 0 && comp->enabled == 0) {
943: comp->enabled = 1;
944: if (! packet_compression)
945: packet_start_compression(6);
946: }
947: }
948:
949: #ifdef PACKET_DEBUG
950: fprintf(stderr, "read/plain[%d]:\r\n",type);
951: buffer_dump(&incoming_packet);
952: #endif
1.40 markus 953: return (u_char)type;
1.25 markus 954: }
955:
956: int
957: packet_read_poll(int *payload_len_ptr)
958: {
959: char *msg;
960: for (;;) {
961: int type = use_ssh2_packet_format ?
962: packet_read_poll2(payload_len_ptr):
963: packet_read_poll1(payload_len_ptr);
964:
965: if(compat20) {
966: int reason;
967: if (type != 0)
968: DBG(debug("received packet type %d", type));
969: switch(type) {
970: case SSH2_MSG_IGNORE:
971: break;
972: case SSH2_MSG_DEBUG:
973: packet_get_char();
974: msg = packet_get_string(NULL);
975: debug("Remote: %.900s", msg);
976: xfree(msg);
977: msg = packet_get_string(NULL);
978: xfree(msg);
979: break;
980: case SSH2_MSG_DISCONNECT:
981: reason = packet_get_int();
982: msg = packet_get_string(NULL);
1.41 markus 983: log("Received disconnect from %s: %d: %.400s", get_remote_ipaddr(),
984: reason, msg);
1.25 markus 985: xfree(msg);
986: fatal_cleanup();
987: break;
988: default:
989: return type;
990: break;
1.48 stevesk 991: }
1.25 markus 992: } else {
993: switch(type) {
994: case SSH_MSG_IGNORE:
995: break;
996: case SSH_MSG_DEBUG:
997: msg = packet_get_string(NULL);
998: debug("Remote: %.900s", msg);
999: xfree(msg);
1000: break;
1001: case SSH_MSG_DISCONNECT:
1002: msg = packet_get_string(NULL);
1.41 markus 1003: log("Received disconnect from %s: %.400s", get_remote_ipaddr(),
1004: msg);
1.25 markus 1005: fatal_cleanup();
1006: xfree(msg);
1007: break;
1008: default:
1009: if (type != 0)
1010: DBG(debug("received packet type %d", type));
1011: return type;
1012: break;
1.48 stevesk 1013: }
1.25 markus 1014: }
1015: }
1016: }
1017:
1.16 markus 1018: /*
1019: * Buffers the given amount of input characters. This is intended to be used
1020: * together with packet_read_poll.
1021: */
1.1 deraadt 1022:
1.2 provos 1023: void
1.40 markus 1024: packet_process_incoming(const char *buf, u_int len)
1.1 deraadt 1025: {
1.14 markus 1026: buffer_append(&input, buf, len);
1.1 deraadt 1027: }
1028:
1029: /* Returns a character from the packet. */
1030:
1.40 markus 1031: u_int
1.2 provos 1032: packet_get_char()
1.1 deraadt 1033: {
1.14 markus 1034: char ch;
1035: buffer_get(&incoming_packet, &ch, 1);
1.40 markus 1036: return (u_char) ch;
1.1 deraadt 1037: }
1038:
1039: /* Returns an integer from the packet data. */
1040:
1.40 markus 1041: u_int
1.2 provos 1042: packet_get_int()
1.1 deraadt 1043: {
1.14 markus 1044: return buffer_get_int(&incoming_packet);
1.1 deraadt 1045: }
1046:
1.16 markus 1047: /*
1048: * Returns an arbitrary precision integer from the packet data. The integer
1049: * must have been initialized before this call.
1050: */
1.1 deraadt 1051:
1.2 provos 1052: void
1.14 markus 1053: packet_get_bignum(BIGNUM * value, int *length_ptr)
1.1 deraadt 1054: {
1.14 markus 1055: *length_ptr = buffer_get_bignum(&incoming_packet, value);
1.24 markus 1056: }
1057:
1058: void
1059: packet_get_bignum2(BIGNUM * value, int *length_ptr)
1060: {
1061: *length_ptr = buffer_get_bignum2(&incoming_packet, value);
1062: }
1063:
1064: char *
1065: packet_get_raw(int *length_ptr)
1066: {
1067: int bytes = buffer_len(&incoming_packet);
1068: if (length_ptr != NULL)
1069: *length_ptr = bytes;
1070: return buffer_ptr(&incoming_packet);
1.28 markus 1071: }
1072:
1073: int
1074: packet_remaining(void)
1075: {
1076: return buffer_len(&incoming_packet);
1.1 deraadt 1077: }
1078:
1.16 markus 1079: /*
1080: * Returns a string from the packet data. The string is allocated using
1081: * xmalloc; it is the responsibility of the calling program to free it when
1082: * no longer needed. The length_ptr argument may be NULL, or point to an
1083: * integer into which the length of the string is stored.
1084: */
1.1 deraadt 1085:
1.16 markus 1086: char *
1.40 markus 1087: packet_get_string(u_int *length_ptr)
1.1 deraadt 1088: {
1.14 markus 1089: return buffer_get_string(&incoming_packet, length_ptr);
1.1 deraadt 1090: }
1091:
1.16 markus 1092: /*
1093: * Sends a diagnostic message from the server to the client. This message
1094: * can be sent at any time (but not while constructing another message). The
1095: * message is printed immediately, but only if the client is being executed
1096: * in verbose mode. These messages are primarily intended to ease debugging
1097: * authentication problems. The length of the formatted message must not
1098: * exceed 1024 bytes. This will automatically call packet_write_wait.
1099: */
1.1 deraadt 1100:
1.2 provos 1101: void
1.14 markus 1102: packet_send_debug(const char *fmt,...)
1.1 deraadt 1103: {
1.14 markus 1104: char buf[1024];
1105: va_list args;
1.39 markus 1106:
1107: if (compat20 && (datafellows & SSH_BUG_DEBUG))
1108: return;
1.14 markus 1109:
1110: va_start(args, fmt);
1111: vsnprintf(buf, sizeof(buf), fmt, args);
1112: va_end(args);
1113:
1.30 markus 1114: if (compat20) {
1115: packet_start(SSH2_MSG_DEBUG);
1116: packet_put_char(0); /* bool: always display */
1117: packet_put_cstring(buf);
1118: packet_put_cstring("");
1119: } else {
1120: packet_start(SSH_MSG_DEBUG);
1121: packet_put_cstring(buf);
1122: }
1.14 markus 1123: packet_send();
1124: packet_write_wait();
1.1 deraadt 1125: }
1126:
1.16 markus 1127: /*
1128: * Logs the error plus constructs and sends a disconnect packet, closes the
1129: * connection, and exits. This function never returns. The error message
1130: * should not contain a newline. The length of the formatted message must
1131: * not exceed 1024 bytes.
1132: */
1.1 deraadt 1133:
1.2 provos 1134: void
1.14 markus 1135: packet_disconnect(const char *fmt,...)
1.1 deraadt 1136: {
1.14 markus 1137: char buf[1024];
1138: va_list args;
1139: static int disconnecting = 0;
1140: if (disconnecting) /* Guard against recursive invocations. */
1141: fatal("packet_disconnect called recursively.");
1142: disconnecting = 1;
1143:
1.16 markus 1144: /*
1145: * Format the message. Note that the caller must make sure the
1146: * message is of limited size.
1147: */
1.14 markus 1148: va_start(args, fmt);
1149: vsnprintf(buf, sizeof(buf), fmt, args);
1150: va_end(args);
1151:
1152: /* Send the disconnect message to the other side, and wait for it to get sent. */
1.25 markus 1153: if (compat20) {
1154: packet_start(SSH2_MSG_DISCONNECT);
1155: packet_put_int(SSH2_DISCONNECT_PROTOCOL_ERROR);
1156: packet_put_cstring(buf);
1157: packet_put_cstring("");
1158: } else {
1159: packet_start(SSH_MSG_DISCONNECT);
1160: packet_put_string(buf, strlen(buf));
1161: }
1.14 markus 1162: packet_send();
1163: packet_write_wait();
1164:
1165: /* Stop listening for connections. */
1166: channel_stop_listening();
1167:
1168: /* Close the connection. */
1169: packet_close();
1.1 deraadt 1170:
1.14 markus 1171: /* Display the error locally and exit. */
1.17 markus 1172: log("Disconnecting: %.100s", buf);
1173: fatal_cleanup();
1.1 deraadt 1174: }
1175:
1.16 markus 1176: /* Checks if there is any buffered output, and tries to write some of the output. */
1.1 deraadt 1177:
1.2 provos 1178: void
1179: packet_write_poll()
1.1 deraadt 1180: {
1.14 markus 1181: int len = buffer_len(&output);
1182: if (len > 0) {
1183: len = write(connection_out, buffer_ptr(&output), len);
1184: if (len <= 0) {
1185: if (errno == EAGAIN)
1186: return;
1187: else
1188: fatal("Write failed: %.100s", strerror(errno));
1189: }
1190: buffer_consume(&output, len);
1191: }
1.1 deraadt 1192: }
1193:
1.16 markus 1194: /*
1195: * Calls packet_write_poll repeatedly until all pending output data has been
1196: * written.
1197: */
1.1 deraadt 1198:
1.2 provos 1199: void
1200: packet_write_wait()
1.1 deraadt 1201: {
1.14 markus 1202: packet_write_poll();
1203: while (packet_have_data_to_write()) {
1204: fd_set set;
1205: FD_ZERO(&set);
1206: FD_SET(connection_out, &set);
1207: select(connection_out + 1, NULL, &set, NULL, NULL);
1208: packet_write_poll();
1209: }
1.1 deraadt 1210: }
1211:
1212: /* Returns true if there is buffered data to write to the connection. */
1213:
1.2 provos 1214: int
1215: packet_have_data_to_write()
1.1 deraadt 1216: {
1.14 markus 1217: return buffer_len(&output) != 0;
1.1 deraadt 1218: }
1219:
1220: /* Returns true if there is not too much data to write to the connection. */
1221:
1.2 provos 1222: int
1223: packet_not_very_much_data_to_write()
1.1 deraadt 1224: {
1.14 markus 1225: if (interactive_mode)
1226: return buffer_len(&output) < 16384;
1227: else
1228: return buffer_len(&output) < 128 * 1024;
1.1 deraadt 1229: }
1230:
1231: /* Informs that the current session is interactive. Sets IP flags for that. */
1232:
1.2 provos 1233: void
1.43 markus 1234: packet_set_interactive(int interactive)
1.1 deraadt 1235: {
1.43 markus 1236: static int called = 0;
1.44 markus 1237: int lowdelay = IPTOS_LOWDELAY;
1238: int throughput = IPTOS_THROUGHPUT;
1239: int on = 1;
1240:
1.43 markus 1241: if (called)
1242: return;
1243: called = 1;
1.1 deraadt 1244:
1.14 markus 1245: /* Record that we are in interactive mode. */
1246: interactive_mode = interactive;
1.1 deraadt 1247:
1.19 markus 1248: /* Only set socket options if using a socket. */
1249: if (!packet_connection_is_on_socket())
1.14 markus 1250: return;
1.19 markus 1251: /*
1.42 markus 1252: * IPTOS_LOWDELAY and IPTOS_THROUGHPUT are IPv4 only
1.19 markus 1253: */
1.14 markus 1254: if (interactive) {
1.16 markus 1255: /*
1256: * Set IP options for an interactive connection. Use
1257: * IPTOS_LOWDELAY and TCP_NODELAY.
1258: */
1.42 markus 1259: if (packet_connection_is_ipv4()) {
1260: if (setsockopt(connection_in, IPPROTO_IP, IP_TOS,
1261: (void *) &lowdelay, sizeof(lowdelay)) < 0)
1262: error("setsockopt IPTOS_LOWDELAY: %.100s",
1263: strerror(errno));
1264: }
1.14 markus 1265: if (setsockopt(connection_in, IPPROTO_TCP, TCP_NODELAY, (void *) &on,
1.19 markus 1266: sizeof(on)) < 0)
1.14 markus 1267: error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
1.42 markus 1268: } else if (packet_connection_is_ipv4()) {
1.16 markus 1269: /*
1270: * Set IP options for a non-interactive connection. Use
1271: * IPTOS_THROUGHPUT.
1272: */
1.14 markus 1273: if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *) &throughput,
1.19 markus 1274: sizeof(throughput)) < 0)
1.14 markus 1275: error("setsockopt IPTOS_THROUGHPUT: %.100s", strerror(errno));
1276: }
1.1 deraadt 1277: }
1278:
1279: /* Returns true if the current connection is interactive. */
1280:
1.2 provos 1281: int
1282: packet_is_interactive()
1.1 deraadt 1283: {
1.14 markus 1284: return interactive_mode;
1.12 markus 1285: }
1286:
1287: int
1288: packet_set_maxsize(int s)
1289: {
1.14 markus 1290: static int called = 0;
1291: if (called) {
1.25 markus 1292: log("packet_set_maxsize: called twice: old %d new %d",
1293: max_packet_size, s);
1.14 markus 1294: return -1;
1295: }
1296: if (s < 4 * 1024 || s > 1024 * 1024) {
1297: log("packet_set_maxsize: bad size %d", s);
1298: return -1;
1299: }
1300: log("packet_set_maxsize: setting to %d", s);
1301: max_packet_size = s;
1302: return s;
1.1 deraadt 1303: }
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