Annotation of src/usr.bin/ssh/packet.c, Revision 1.12
1.1 deraadt 1: /*
2:
3: packet.c
4:
5: Author: Tatu Ylonen <ylo@cs.hut.fi>
6:
7: Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
8: All rights reserved
9:
10: Created: Sat Mar 18 02:40:40 1995 ylo
11:
12: This file contains code implementing the packet protocol and communication
13: with the other side. This same code is used both on client and server side.
14:
15: */
16:
17: #include "includes.h"
1.12 ! markus 18: RCSID("$Id: packet.c,v 1.11 1999/11/15 21:38:54 markus Exp $");
1.1 deraadt 19:
20: #include "xmalloc.h"
21: #include "buffer.h"
22: #include "packet.h"
23: #include "bufaux.h"
24: #include "ssh.h"
25: #include "crc32.h"
26: #include "cipher.h"
27: #include "getput.h"
28:
29: #include "compress.h"
1.9 dugsong 30: #include "deattack.h"
1.1 deraadt 31:
32: /* This variable contains the file descriptors used for communicating with
33: the other side. connection_in is used for reading; connection_out
34: for writing. These can be the same descriptor, in which case it is
35: assumed to be a socket. */
36: static int connection_in = -1;
37: static int connection_out = -1;
38:
39: /* Cipher type. This value is only used to determine whether to pad the
40: packets with zeroes or random data. */
41: static int cipher_type = SSH_CIPHER_NONE;
42:
43: /* Protocol flags for the remote side. */
44: static unsigned int remote_protocol_flags = 0;
45:
46: /* Encryption context for receiving data. This is only used for decryption. */
47: static CipherContext receive_context;
48: /* Encryption coontext for sending data. This is only used for encryption. */
49: static CipherContext send_context;
50:
51: /* Buffer for raw input data from the socket. */
52: static Buffer input;
53:
54: /* Buffer for raw output data going to the socket. */
55: static Buffer output;
56:
57: /* Buffer for the partial outgoing packet being constructed. */
58: static Buffer outgoing_packet;
59:
60: /* Buffer for the incoming packet currently being processed. */
61: static Buffer incoming_packet;
62:
63: /* Scratch buffer for packet compression/decompression. */
64: static Buffer compression_buffer;
65:
66: /* Flag indicating whether packet compression/decompression is enabled. */
67: static int packet_compression = 0;
68:
1.12 ! markus 69: /* default maximum packet size */
! 70: int max_packet_size = 32768;
! 71:
1.1 deraadt 72: /* Flag indicating whether this module has been initialized. */
73: static int initialized = 0;
74:
75: /* Set to true if the connection is interactive. */
76: static int interactive_mode = 0;
77:
78: /* Sets the descriptors used for communication. Disables encryption until
79: packet_set_encryption_key is called. */
80:
1.2 provos 81: void
82: packet_set_connection(int fd_in, int fd_out)
1.1 deraadt 83: {
84: connection_in = fd_in;
85: connection_out = fd_out;
86: cipher_type = SSH_CIPHER_NONE;
87: cipher_set_key(&send_context, SSH_CIPHER_NONE, (unsigned char *)"", 0, 1);
88: cipher_set_key(&receive_context, SSH_CIPHER_NONE, (unsigned char *)"", 0, 0);
89: if (!initialized)
90: {
91: initialized = 1;
92: buffer_init(&input);
93: buffer_init(&output);
94: buffer_init(&outgoing_packet);
95: buffer_init(&incoming_packet);
96: }
97:
98: /* Kludge: arrange the close function to be called from fatal(). */
99: fatal_add_cleanup((void (*)(void *))packet_close, NULL);
100: }
101:
102: /* Sets the connection into non-blocking mode. */
103:
1.2 provos 104: void
105: packet_set_nonblocking()
1.1 deraadt 106: {
107: /* Set the socket into non-blocking mode. */
108: if (fcntl(connection_in, F_SETFL, O_NONBLOCK) < 0)
109: error("fcntl O_NONBLOCK: %.100s", strerror(errno));
110:
111: if (connection_out != connection_in)
112: {
113: if (fcntl(connection_out, F_SETFL, O_NONBLOCK) < 0)
114: error("fcntl O_NONBLOCK: %.100s", strerror(errno));
115: }
116: }
117:
118: /* Returns the socket used for reading. */
119:
1.2 provos 120: int
121: packet_get_connection_in()
1.1 deraadt 122: {
123: return connection_in;
124: }
125:
126: /* Returns the descriptor used for writing. */
127:
1.2 provos 128: int
129: packet_get_connection_out()
1.1 deraadt 130: {
131: return connection_out;
132: }
133:
134: /* Closes the connection and clears and frees internal data structures. */
135:
1.2 provos 136: void
137: packet_close()
1.1 deraadt 138: {
139: if (!initialized)
140: return;
141: initialized = 0;
142: if (connection_in == connection_out)
143: {
1.8 deraadt 144: shutdown(connection_out, SHUT_RDWR);
1.1 deraadt 145: close(connection_out);
146: }
147: else
148: {
149: close(connection_in);
150: close(connection_out);
151: }
152: buffer_free(&input);
153: buffer_free(&output);
154: buffer_free(&outgoing_packet);
155: buffer_free(&incoming_packet);
156: if (packet_compression)
157: {
158: buffer_free(&compression_buffer);
159: buffer_compress_uninit();
160: }
161: }
162:
163: /* Sets remote side protocol flags. */
164:
1.2 provos 165: void
166: packet_set_protocol_flags(unsigned int protocol_flags)
1.1 deraadt 167: {
168: remote_protocol_flags = protocol_flags;
169: channel_set_options((protocol_flags & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) != 0);
170: }
171:
172: /* Returns the remote protocol flags set earlier by the above function. */
173:
1.2 provos 174: unsigned int
175: packet_get_protocol_flags()
1.1 deraadt 176: {
177: return remote_protocol_flags;
178: }
179:
180: /* Starts packet compression from the next packet on in both directions.
181: Level is compression level 1 (fastest) - 9 (slow, best) as in gzip. */
182:
1.2 provos 183: void
184: packet_start_compression(int level)
1.1 deraadt 185: {
186: if (packet_compression)
187: fatal("Compression already enabled.");
188: packet_compression = 1;
189: buffer_init(&compression_buffer);
190: buffer_compress_init(level);
191: }
192:
193: /* Encrypts the given number of bytes, copying from src to dest.
194: bytes is known to be a multiple of 8. */
195:
1.2 provos 196: void
197: packet_encrypt(CipherContext *cc, void *dest, void *src,
198: unsigned int bytes)
1.1 deraadt 199: {
200: cipher_encrypt(cc, dest, src, bytes);
201: }
202:
203: /* Decrypts the given number of bytes, copying from src to dest.
204: bytes is known to be a multiple of 8. */
205:
1.2 provos 206: void
207: packet_decrypt(CipherContext *cc, void *dest, void *src,
208: unsigned int bytes)
1.1 deraadt 209: {
1.9 dugsong 210: int i;
211:
1.10 markus 212: if ((bytes % 8) != 0)
213: fatal("packet_decrypt: bad ciphertext length %d", bytes);
1.9 dugsong 214:
215: /*
216: Cryptographic attack detector for ssh - Modifications for packet.c
217: (C)1998 CORE-SDI, Buenos Aires Argentina
218: Ariel Futoransky(futo@core-sdi.com)
219: */
220: switch (cc->type)
221: {
222: case SSH_CIPHER_NONE:
223: i = DEATTACK_OK;
224: break;
225: default:
226: i = detect_attack(src, bytes, NULL);
227: break;
228: }
229:
230: if (i == DEATTACK_DETECTED)
231: packet_disconnect("crc32 compensation attack: network attack detected");
232:
1.1 deraadt 233: cipher_decrypt(cc, dest, src, bytes);
234: }
235:
236: /* Causes any further packets to be encrypted using the given key. The same
237: key is used for both sending and reception. However, both directions
238: are encrypted independently of each other. */
239:
1.2 provos 240: void
241: packet_set_encryption_key(const unsigned char *key, unsigned int keylen,
1.11 markus 242: int cipher)
1.1 deraadt 243: {
1.11 markus 244: /* All other ciphers use the same key in both directions for now. */
245: cipher_set_key(&receive_context, cipher, key, keylen, 0);
246: cipher_set_key(&send_context, cipher, key, keylen, 1);
1.1 deraadt 247: }
248:
249: /* Starts constructing a packet to send. */
250:
1.2 provos 251: void
252: packet_start(int type)
1.1 deraadt 253: {
254: char buf[9];
255:
256: buffer_clear(&outgoing_packet);
257: memset(buf, 0, 8);
258: buf[8] = type;
259: buffer_append(&outgoing_packet, buf, 9);
260: }
261:
262: /* Appends a character to the packet data. */
263:
1.2 provos 264: void
265: packet_put_char(int value)
1.1 deraadt 266: {
267: char ch = value;
268: buffer_append(&outgoing_packet, &ch, 1);
269: }
270:
271: /* Appends an integer to the packet data. */
272:
1.2 provos 273: void
274: packet_put_int(unsigned int value)
1.1 deraadt 275: {
276: buffer_put_int(&outgoing_packet, value);
277: }
278:
279: /* Appends a string to packet data. */
280:
1.2 provos 281: void
282: packet_put_string(const char *buf, unsigned int len)
1.1 deraadt 283: {
284: buffer_put_string(&outgoing_packet, buf, len);
285: }
286:
287: /* Appends an arbitrary precision integer to packet data. */
288:
1.2 provos 289: void
290: packet_put_bignum(BIGNUM *value)
1.1 deraadt 291: {
1.2 provos 292: buffer_put_bignum(&outgoing_packet, value);
1.1 deraadt 293: }
294:
295: /* Finalizes and sends the packet. If the encryption key has been set,
296: encrypts the packet before sending. */
297:
1.2 provos 298: void
299: packet_send()
1.1 deraadt 300: {
301: char buf[8], *cp;
302: int i, padding, len;
1.7 deraadt 303: unsigned int checksum;
1.3 dugsong 304: u_int32_t rand = 0;
1.1 deraadt 305:
306: /* If using packet compression, compress the payload of the outgoing
307: packet. */
308: if (packet_compression)
309: {
310: buffer_clear(&compression_buffer);
311: buffer_consume(&outgoing_packet, 8); /* Skip padding. */
312: buffer_append(&compression_buffer, "\0\0\0\0\0\0\0\0", 8); /* padding */
313: buffer_compress(&outgoing_packet, &compression_buffer);
314: buffer_clear(&outgoing_packet);
315: buffer_append(&outgoing_packet, buffer_ptr(&compression_buffer),
316: buffer_len(&compression_buffer));
317: }
318:
319: /* Compute packet length without padding (add checksum, remove padding). */
320: len = buffer_len(&outgoing_packet) + 4 - 8;
321:
322: /* Insert padding. */
323: padding = 8 - len % 8;
324: if (cipher_type != SSH_CIPHER_NONE)
325: {
326: cp = buffer_ptr(&outgoing_packet);
1.2 provos 327: for (i = 0; i < padding; i++) {
328: if (i % 4 == 0)
329: rand = arc4random();
330: cp[7 - i] = rand & 0xff;
331: rand >>= 8;
332: }
1.1 deraadt 333: }
334: buffer_consume(&outgoing_packet, 8 - padding);
335:
336: /* Add check bytes. */
337: checksum = crc32((unsigned char *)buffer_ptr(&outgoing_packet),
338: buffer_len(&outgoing_packet));
339: PUT_32BIT(buf, checksum);
340: buffer_append(&outgoing_packet, buf, 4);
341:
342: #ifdef PACKET_DEBUG
343: fprintf(stderr, "packet_send plain: ");
344: buffer_dump(&outgoing_packet);
345: #endif
346:
347: /* Append to output. */
348: PUT_32BIT(buf, len);
349: buffer_append(&output, buf, 4);
350: buffer_append_space(&output, &cp, buffer_len(&outgoing_packet));
351: packet_encrypt(&send_context, cp, buffer_ptr(&outgoing_packet),
352: buffer_len(&outgoing_packet));
353:
354: #ifdef PACKET_DEBUG
355: fprintf(stderr, "encrypted: "); buffer_dump(&output);
356: #endif
357:
358: buffer_clear(&outgoing_packet);
359:
360: /* Note that the packet is now only buffered in output. It won\'t be
361: actually sent until packet_write_wait or packet_write_poll is called. */
362: }
363:
364: /* Waits until a packet has been received, and returns its type. Note that
365: no other data is processed until this returns, so this function should
366: not be used during the interactive session. */
367:
1.2 provos 368: int
369: packet_read(int *payload_len_ptr)
1.1 deraadt 370: {
371: int type, len;
372: fd_set set;
373: char buf[8192];
374:
375: /* Since we are blocking, ensure that all written packets have been sent. */
376: packet_write_wait();
377:
378: /* Stay in the loop until we have received a complete packet. */
379: for (;;)
380: {
381: /* Try to read a packet from the buffer. */
382: type = packet_read_poll(payload_len_ptr);
383: if (type == SSH_SMSG_SUCCESS
384: || type == SSH_SMSG_FAILURE
385: || type == SSH_CMSG_EOF
386: || type == SSH_CMSG_EXIT_CONFIRMATION)
387: packet_integrity_check(*payload_len_ptr, 0, type);
388: /* If we got a packet, return it. */
389: if (type != SSH_MSG_NONE)
390: return type;
391: /* Otherwise, wait for some data to arrive, add it to the buffer,
392: and try again. */
393: FD_ZERO(&set);
394: FD_SET(connection_in, &set);
395: /* Wait for some data to arrive. */
396: select(connection_in + 1, &set, NULL, NULL, NULL);
397: /* Read data from the socket. */
398: len = read(connection_in, buf, sizeof(buf));
399: if (len == 0)
400: fatal("Connection closed by remote host.");
401: if (len < 0)
402: fatal("Read from socket failed: %.100s", strerror(errno));
403: /* Append it to the buffer. */
404: packet_process_incoming(buf, len);
405: }
406: /*NOTREACHED*/
407: }
408:
409: /* Waits until a packet has been received, verifies that its type matches
410: that given, and gives a fatal error and exits if there is a mismatch. */
411:
1.2 provos 412: void
413: packet_read_expect(int *payload_len_ptr, int expected_type)
1.1 deraadt 414: {
415: int type;
416:
417: type = packet_read(payload_len_ptr);
418: if (type != expected_type)
419: packet_disconnect("Protocol error: expected packet type %d, got %d",
420: expected_type, type);
421: }
422:
423: /* Checks if a full packet is available in the data received so far via
424: packet_process_incoming. If so, reads the packet; otherwise returns
425: SSH_MSG_NONE. This does not wait for data from the connection.
426:
427: SSH_MSG_DISCONNECT is handled specially here. Also,
428: SSH_MSG_IGNORE messages are skipped by this function and are never returned
429: to higher levels.
430:
431: The returned payload_len does include space consumed by:
432: Packet length
433: Padding
434: Packet type
435: Check bytes
436:
437:
438: */
439:
1.2 provos 440: int
441: packet_read_poll(int *payload_len_ptr)
1.1 deraadt 442: {
443: unsigned int len, padded_len;
444: unsigned char *ucp;
445: char buf[8], *cp;
1.7 deraadt 446: unsigned int checksum, stored_checksum;
1.1 deraadt 447:
448: restart:
449:
450: /* Check if input size is less than minimum packet size. */
451: if (buffer_len(&input) < 4 + 8)
452: return SSH_MSG_NONE;
453: /* Get length of incoming packet. */
454: ucp = (unsigned char *)buffer_ptr(&input);
455: len = GET_32BIT(ucp);
456: if (len < 1 + 2 + 2 || len > 256*1024)
457: packet_disconnect("Bad packet length %d.", len);
458: padded_len = (len + 8) & ~7;
459:
460: /* Check if the packet has been entirely received. */
461: if (buffer_len(&input) < 4 + padded_len)
462: return SSH_MSG_NONE;
463:
464: /* The entire packet is in buffer. */
465:
466: /* Consume packet length. */
467: buffer_consume(&input, 4);
468:
469: /* Copy data to incoming_packet. */
470: buffer_clear(&incoming_packet);
471: buffer_append_space(&incoming_packet, &cp, padded_len);
472: packet_decrypt(&receive_context, cp, buffer_ptr(&input), padded_len);
473: buffer_consume(&input, padded_len);
474:
475: #ifdef PACKET_DEBUG
476: fprintf(stderr, "read_poll plain: "); buffer_dump(&incoming_packet);
477: #endif
478:
479: /* Compute packet checksum. */
480: checksum = crc32((unsigned char *)buffer_ptr(&incoming_packet),
481: buffer_len(&incoming_packet) - 4);
482:
483: /* Skip padding. */
484: buffer_consume(&incoming_packet, 8 - len % 8);
485:
486: /* Test check bytes. */
1.10 markus 487:
488: if (len != buffer_len(&incoming_packet))
489: packet_disconnect("packet_read_poll: len %d != buffer_len %d.",
490: len, buffer_len(&incoming_packet));
491:
1.1 deraadt 492: ucp = (unsigned char *)buffer_ptr(&incoming_packet) + len - 4;
493: stored_checksum = GET_32BIT(ucp);
494: if (checksum != stored_checksum)
495: packet_disconnect("Corrupted check bytes on input.");
496: buffer_consume_end(&incoming_packet, 4);
497:
498: /* If using packet compression, decompress the packet. */
499: if (packet_compression)
500: {
501: buffer_clear(&compression_buffer);
502: buffer_uncompress(&incoming_packet, &compression_buffer);
503: buffer_clear(&incoming_packet);
504: buffer_append(&incoming_packet, buffer_ptr(&compression_buffer),
505: buffer_len(&compression_buffer));
506: }
507:
508: /* Get packet type. */
509: buffer_get(&incoming_packet, &buf[0], 1);
510:
511: /* Return length of payload (without type field). */
512: *payload_len_ptr = buffer_len(&incoming_packet);
513:
514: /* Handle disconnect message. */
515: if ((unsigned char)buf[0] == SSH_MSG_DISCONNECT)
516: fatal("%.900s", packet_get_string(NULL));
517:
518: /* Ignore ignore messages. */
519: if ((unsigned char)buf[0] == SSH_MSG_IGNORE)
520: goto restart;
521:
522: /* Send debug messages as debugging output. */
523: if ((unsigned char)buf[0] == SSH_MSG_DEBUG)
524: {
525: debug("Remote: %.900s", packet_get_string(NULL));
526: goto restart;
527: }
528:
529: /* Return type. */
530: return (unsigned char)buf[0];
531: }
532:
533: /* Buffers the given amount of input characters. This is intended to be
534: used together with packet_read_poll. */
535:
1.2 provos 536: void
537: packet_process_incoming(const char *buf, unsigned int len)
1.1 deraadt 538: {
539: buffer_append(&input, buf, len);
540: }
541:
542: /* Returns a character from the packet. */
543:
1.2 provos 544: unsigned int
545: packet_get_char()
1.1 deraadt 546: {
547: char ch;
548: buffer_get(&incoming_packet, &ch, 1);
549: return (unsigned char)ch;
550: }
551:
552: /* Returns an integer from the packet data. */
553:
1.2 provos 554: unsigned int
555: packet_get_int()
1.1 deraadt 556: {
557: return buffer_get_int(&incoming_packet);
558: }
559:
560: /* Returns an arbitrary precision integer from the packet data. The integer
561: must have been initialized before this call. */
562:
1.2 provos 563: void
564: packet_get_bignum(BIGNUM *value, int *length_ptr)
1.1 deraadt 565: {
1.2 provos 566: *length_ptr = buffer_get_bignum(&incoming_packet, value);
1.1 deraadt 567: }
568:
569: /* Returns a string from the packet data. The string is allocated using
570: xmalloc; it is the responsibility of the calling program to free it when
571: no longer needed. The length_ptr argument may be NULL, or point to an
572: integer into which the length of the string is stored. */
573:
1.2 provos 574: char
575: *packet_get_string(unsigned int *length_ptr)
1.1 deraadt 576: {
577: return buffer_get_string(&incoming_packet, length_ptr);
578: }
579:
580: /* Sends a diagnostic message from the server to the client. This message
581: can be sent at any time (but not while constructing another message).
582: The message is printed immediately, but only if the client is being
583: executed in verbose mode. These messages are primarily intended to
584: ease debugging authentication problems. The length of the formatted
585: message must not exceed 1024 bytes. This will automatically call
586: packet_write_wait. */
587:
1.2 provos 588: void
589: packet_send_debug(const char *fmt, ...)
1.1 deraadt 590: {
591: char buf[1024];
592: va_list args;
593:
594: va_start(args, fmt);
595: vsnprintf(buf, sizeof(buf), fmt, args);
596: va_end(args);
597:
598: packet_start(SSH_MSG_DEBUG);
599: packet_put_string(buf, strlen(buf));
600: packet_send();
601: packet_write_wait();
602: }
603:
604: /* Logs the error plus constructs and sends a disconnect
605: packet, closes the connection, and exits. This function never returns.
606: The error message should not contain a newline. The length of the
607: formatted message must not exceed 1024 bytes. */
608:
1.2 provos 609: void
610: packet_disconnect(const char *fmt, ...)
1.1 deraadt 611: {
612: char buf[1024];
613: va_list args;
614: static int disconnecting = 0;
615: if (disconnecting) /* Guard against recursive invocations. */
616: fatal("packet_disconnect called recursively.");
617: disconnecting = 1;
618:
619: /* Format the message. Note that the caller must make sure the message
620: is of limited size. */
621: va_start(args, fmt);
622: vsnprintf(buf, sizeof(buf), fmt, args);
623: va_end(args);
624:
625: /* Send the disconnect message to the other side, and wait for it to get
626: sent. */
627: packet_start(SSH_MSG_DISCONNECT);
628: packet_put_string(buf, strlen(buf));
629: packet_send();
630: packet_write_wait();
631:
632: /* Stop listening for connections. */
633: channel_stop_listening();
634:
635: /* Close the connection. */
636: packet_close();
637:
638: /* Display the error locally and exit. */
639: fatal("Local: %.100s", buf);
640: }
641:
642: /* Checks if there is any buffered output, and tries to write some of the
643: output. */
644:
1.2 provos 645: void
646: packet_write_poll()
1.1 deraadt 647: {
648: int len = buffer_len(&output);
649: if (len > 0)
650: {
651: len = write(connection_out, buffer_ptr(&output), len);
1.2 provos 652: if (len <= 0) {
1.1 deraadt 653: if (errno == EAGAIN)
654: return;
655: else
656: fatal("Write failed: %.100s", strerror(errno));
1.2 provos 657: }
1.1 deraadt 658: buffer_consume(&output, len);
659: }
660: }
661:
662: /* Calls packet_write_poll repeatedly until all pending output data has
663: been written. */
664:
1.2 provos 665: void
666: packet_write_wait()
1.1 deraadt 667: {
668: packet_write_poll();
669: while (packet_have_data_to_write())
670: {
671: fd_set set;
672: FD_ZERO(&set);
673: FD_SET(connection_out, &set);
674: select(connection_out + 1, NULL, &set, NULL, NULL);
675: packet_write_poll();
676: }
677: }
678:
679: /* Returns true if there is buffered data to write to the connection. */
680:
1.2 provos 681: int
682: packet_have_data_to_write()
1.1 deraadt 683: {
684: return buffer_len(&output) != 0;
685: }
686:
687: /* Returns true if there is not too much data to write to the connection. */
688:
1.2 provos 689: int
690: packet_not_very_much_data_to_write()
1.1 deraadt 691: {
692: if (interactive_mode)
693: return buffer_len(&output) < 16384;
694: else
695: return buffer_len(&output) < 128*1024;
696: }
697:
698: /* Informs that the current session is interactive. Sets IP flags for that. */
699:
1.2 provos 700: void
701: packet_set_interactive(int interactive, int keepalives)
1.1 deraadt 702: {
703: int on = 1;
704:
705: /* Record that we are in interactive mode. */
706: interactive_mode = interactive;
707:
708: /* Only set socket options if using a socket (as indicated by the descriptors
709: being the same). */
710: if (connection_in != connection_out)
711: return;
712:
713: if (keepalives)
714: {
715: /* Set keepalives if requested. */
716: if (setsockopt(connection_in, SOL_SOCKET, SO_KEEPALIVE, (void *)&on,
717: sizeof(on)) < 0)
718: error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
719: }
720:
721: if (interactive)
722: {
723: /* Set IP options for an interactive connection. Use IPTOS_LOWDELAY
724: and TCP_NODELAY. */
725: int lowdelay = IPTOS_LOWDELAY;
726: if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *)&lowdelay,
727: sizeof(lowdelay)) < 0)
728: error("setsockopt IPTOS_LOWDELAY: %.100s", strerror(errno));
729: if (setsockopt(connection_in, IPPROTO_TCP, TCP_NODELAY, (void *)&on,
730: sizeof(on)) < 0)
731: error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
732: }
733: else
734: {
735: /* Set IP options for a non-interactive connection. Use
736: IPTOS_THROUGHPUT. */
737: int throughput = IPTOS_THROUGHPUT;
738: if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *)&throughput,
739: sizeof(throughput)) < 0)
740: error("setsockopt IPTOS_THROUGHPUT: %.100s", strerror(errno));
741: }
742: }
743:
744: /* Returns true if the current connection is interactive. */
745:
1.2 provos 746: int
747: packet_is_interactive()
1.1 deraadt 748: {
749: return interactive_mode;
1.12 ! markus 750: }
! 751:
! 752: int
! 753: packet_set_maxsize(int s)
! 754: {
! 755: static int called = 0;
! 756: if (called) {
! 757: log("packet_set_maxsize: called twice: old %d new %d", max_packet_size, s);
! 758: return -1;
! 759: }
! 760: if (s < 4*1024 || s > 1024*1024) {
! 761: log("packet_set_maxsize: bad size %d", s);
! 762: return -1;
! 763: }
! 764: log("packet_set_maxsize: setting to %d", s);
! 765: max_packet_size = s;
! 766: return s;
1.1 deraadt 767: }
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