Annotation of src/usr.bin/ssh/packet.c, Revision 1.4
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"
1.4 ! deraadt 18: RCSID("$Id: packet.c,v 1.3 1999/09/29 18:16:19 dugsong 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"
30:
31: /* This variable contains the file descriptors used for communicating with
32: the other side. connection_in is used for reading; connection_out
33: for writing. These can be the same descriptor, in which case it is
34: assumed to be a socket. */
35: static int connection_in = -1;
36: static int connection_out = -1;
37:
38: /* Cipher type. This value is only used to determine whether to pad the
39: packets with zeroes or random data. */
40: static int cipher_type = SSH_CIPHER_NONE;
41:
42: /* Protocol flags for the remote side. */
43: static unsigned int remote_protocol_flags = 0;
44:
45: /* Encryption context for receiving data. This is only used for decryption. */
46: static CipherContext receive_context;
47: /* Encryption coontext for sending data. This is only used for encryption. */
48: static CipherContext send_context;
49:
50: /* Buffer for raw input data from the socket. */
51: static Buffer input;
52:
53: /* Buffer for raw output data going to the socket. */
54: static Buffer output;
55:
56: /* Buffer for the partial outgoing packet being constructed. */
57: static Buffer outgoing_packet;
58:
59: /* Buffer for the incoming packet currently being processed. */
60: static Buffer incoming_packet;
61:
62: /* Scratch buffer for packet compression/decompression. */
63: static Buffer compression_buffer;
64:
65: /* Flag indicating whether packet compression/decompression is enabled. */
66: static int packet_compression = 0;
67:
68: /* Flag indicating whether this module has been initialized. */
69: static int initialized = 0;
70:
71: /* Set to true if the connection is interactive. */
72: static int interactive_mode = 0;
73:
74: /* Sets the descriptors used for communication. Disables encryption until
75: packet_set_encryption_key is called. */
76:
1.2 provos 77: void
78: packet_set_connection(int fd_in, int fd_out)
1.1 deraadt 79: {
80: connection_in = fd_in;
81: connection_out = fd_out;
82: cipher_type = SSH_CIPHER_NONE;
83: cipher_set_key(&send_context, SSH_CIPHER_NONE, (unsigned char *)"", 0, 1);
84: cipher_set_key(&receive_context, SSH_CIPHER_NONE, (unsigned char *)"", 0, 0);
85: if (!initialized)
86: {
87: initialized = 1;
88: buffer_init(&input);
89: buffer_init(&output);
90: buffer_init(&outgoing_packet);
91: buffer_init(&incoming_packet);
92: }
93:
94: /* Kludge: arrange the close function to be called from fatal(). */
95: fatal_add_cleanup((void (*)(void *))packet_close, NULL);
96: }
97:
98: /* Sets the connection into non-blocking mode. */
99:
1.2 provos 100: void
101: packet_set_nonblocking()
1.1 deraadt 102: {
103: /* Set the socket into non-blocking mode. */
104: #if defined(O_NONBLOCK) && !defined(O_NONBLOCK_BROKEN)
105: if (fcntl(connection_in, F_SETFL, O_NONBLOCK) < 0)
106: error("fcntl O_NONBLOCK: %.100s", strerror(errno));
107: #else /* O_NONBLOCK && !O_NONBLOCK_BROKEN */
108: if (fcntl(connection_in, F_SETFL, O_NDELAY) < 0)
109: error("fcntl O_NDELAY: %.100s", strerror(errno));
110: #endif /* O_NONBLOCK && !O_NONBLOCK_BROKEN */
111:
112: if (connection_out != connection_in)
113: {
114: #if defined(O_NONBLOCK) && !defined(O_NONBLOCK_BROKEN)
115: if (fcntl(connection_out, F_SETFL, O_NONBLOCK) < 0)
116: error("fcntl O_NONBLOCK: %.100s", strerror(errno));
117: #else /* O_NONBLOCK && !O_NONBLOCK_BROKEN */
118: if (fcntl(connection_out, F_SETFL, O_NDELAY) < 0)
119: error("fcntl O_NDELAY: %.100s", strerror(errno));
120: #endif /* O_NONBLOCK && !O_NONBLOCK_BROKEN */
121: }
122: }
123:
124: /* Returns the socket used for reading. */
125:
1.2 provos 126: int
127: packet_get_connection_in()
1.1 deraadt 128: {
129: return connection_in;
130: }
131:
132: /* Returns the descriptor used for writing. */
133:
1.2 provos 134: int
135: packet_get_connection_out()
1.1 deraadt 136: {
137: return connection_out;
138: }
139:
140: /* Closes the connection and clears and frees internal data structures. */
141:
1.2 provos 142: void
143: packet_close()
1.1 deraadt 144: {
145: if (!initialized)
146: return;
147: initialized = 0;
148: if (connection_in == connection_out)
149: {
150: shutdown(connection_out, 2);
151: close(connection_out);
152: }
153: else
154: {
155: close(connection_in);
156: close(connection_out);
157: }
158: buffer_free(&input);
159: buffer_free(&output);
160: buffer_free(&outgoing_packet);
161: buffer_free(&incoming_packet);
162: if (packet_compression)
163: {
164: buffer_free(&compression_buffer);
165: buffer_compress_uninit();
166: }
167: }
168:
169: /* Sets remote side protocol flags. */
170:
1.2 provos 171: void
172: packet_set_protocol_flags(unsigned int protocol_flags)
1.1 deraadt 173: {
174: remote_protocol_flags = protocol_flags;
175: channel_set_options((protocol_flags & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) != 0);
176: }
177:
178: /* Returns the remote protocol flags set earlier by the above function. */
179:
1.2 provos 180: unsigned int
181: packet_get_protocol_flags()
1.1 deraadt 182: {
183: return remote_protocol_flags;
184: }
185:
186: /* Starts packet compression from the next packet on in both directions.
187: Level is compression level 1 (fastest) - 9 (slow, best) as in gzip. */
188:
1.2 provos 189: void
190: packet_start_compression(int level)
1.1 deraadt 191: {
192: if (packet_compression)
193: fatal("Compression already enabled.");
194: packet_compression = 1;
195: buffer_init(&compression_buffer);
196: buffer_compress_init(level);
197: }
198:
199: /* Encrypts the given number of bytes, copying from src to dest.
200: bytes is known to be a multiple of 8. */
201:
1.2 provos 202: void
203: packet_encrypt(CipherContext *cc, void *dest, void *src,
204: unsigned int bytes)
1.1 deraadt 205: {
206: assert((bytes % 8) == 0);
207: cipher_encrypt(cc, dest, src, bytes);
208: }
209:
210: /* Decrypts the given number of bytes, copying from src to dest.
211: bytes is known to be a multiple of 8. */
212:
1.2 provos 213: void
214: packet_decrypt(CipherContext *cc, void *dest, void *src,
215: unsigned int bytes)
1.1 deraadt 216: {
217: assert((bytes % 8) == 0);
218: cipher_decrypt(cc, dest, src, bytes);
219: }
220:
221: /* Causes any further packets to be encrypted using the given key. The same
222: key is used for both sending and reception. However, both directions
223: are encrypted independently of each other. */
224:
1.2 provos 225: void
226: packet_set_encryption_key(const unsigned char *key, unsigned int keylen,
227: int cipher, int is_client)
1.1 deraadt 228: {
229: cipher_type = cipher;
230: if (cipher == SSH_CIPHER_RC4)
231: {
232: if (is_client)
233: { /* In client: use first half for receiving, second for sending. */
234: cipher_set_key(&receive_context, cipher, key, keylen / 2, 0);
235: cipher_set_key(&send_context, cipher, key + keylen / 2,
236: keylen / 2, 1);
237: }
238: else
239: { /* In server: use first half for sending, second for receiving. */
240: cipher_set_key(&receive_context, cipher, key + keylen / 2,
241: keylen / 2, 0);
242: cipher_set_key(&send_context, cipher, key, keylen / 2, 1);
243: }
244: }
245: else
246: {
247: /* All other ciphers use the same key in both directions for now. */
248: cipher_set_key(&receive_context, cipher, key, keylen, 0);
249: cipher_set_key(&send_context, cipher, key, keylen, 1);
250: }
251: }
252:
253: /* Starts constructing a packet to send. */
254:
1.2 provos 255: void
256: packet_start(int type)
1.1 deraadt 257: {
258: char buf[9];
259:
260: buffer_clear(&outgoing_packet);
261: memset(buf, 0, 8);
262: buf[8] = type;
263: buffer_append(&outgoing_packet, buf, 9);
264: }
265:
266: /* Appends a character to the packet data. */
267:
1.2 provos 268: void
269: packet_put_char(int value)
1.1 deraadt 270: {
271: char ch = value;
272: buffer_append(&outgoing_packet, &ch, 1);
273: }
274:
275: /* Appends an integer to the packet data. */
276:
1.2 provos 277: void
278: packet_put_int(unsigned int value)
1.1 deraadt 279: {
280: buffer_put_int(&outgoing_packet, value);
281: }
282:
283: /* Appends a string to packet data. */
284:
1.2 provos 285: void
286: packet_put_string(const char *buf, unsigned int len)
1.1 deraadt 287: {
288: buffer_put_string(&outgoing_packet, buf, len);
289: }
290:
291: /* Appends an arbitrary precision integer to packet data. */
292:
1.2 provos 293: void
294: packet_put_bignum(BIGNUM *value)
1.1 deraadt 295: {
1.2 provos 296: buffer_put_bignum(&outgoing_packet, value);
1.1 deraadt 297: }
298:
299: /* Finalizes and sends the packet. If the encryption key has been set,
300: encrypts the packet before sending. */
301:
1.2 provos 302: void
303: packet_send()
1.1 deraadt 304: {
305: char buf[8], *cp;
306: int i, padding, len;
307: unsigned long checksum;
1.3 dugsong 308: u_int32_t rand = 0;
1.1 deraadt 309:
310: /* If using packet compression, compress the payload of the outgoing
311: packet. */
312: if (packet_compression)
313: {
314: buffer_clear(&compression_buffer);
315: buffer_consume(&outgoing_packet, 8); /* Skip padding. */
316: buffer_append(&compression_buffer, "\0\0\0\0\0\0\0\0", 8); /* padding */
317: buffer_compress(&outgoing_packet, &compression_buffer);
318: buffer_clear(&outgoing_packet);
319: buffer_append(&outgoing_packet, buffer_ptr(&compression_buffer),
320: buffer_len(&compression_buffer));
321: }
322:
323: /* Compute packet length without padding (add checksum, remove padding). */
324: len = buffer_len(&outgoing_packet) + 4 - 8;
325:
326: /* Insert padding. */
327: padding = 8 - len % 8;
328: if (cipher_type != SSH_CIPHER_NONE)
329: {
330: cp = buffer_ptr(&outgoing_packet);
1.2 provos 331: for (i = 0; i < padding; i++) {
332: if (i % 4 == 0)
333: rand = arc4random();
334: cp[7 - i] = rand & 0xff;
335: rand >>= 8;
336: }
1.1 deraadt 337: }
338: buffer_consume(&outgoing_packet, 8 - padding);
339:
340: /* Add check bytes. */
341: checksum = crc32((unsigned char *)buffer_ptr(&outgoing_packet),
342: buffer_len(&outgoing_packet));
343: PUT_32BIT(buf, checksum);
344: buffer_append(&outgoing_packet, buf, 4);
345:
346: #ifdef PACKET_DEBUG
347: fprintf(stderr, "packet_send plain: ");
348: buffer_dump(&outgoing_packet);
349: #endif
350:
351: /* Append to output. */
352: PUT_32BIT(buf, len);
353: buffer_append(&output, buf, 4);
354: buffer_append_space(&output, &cp, buffer_len(&outgoing_packet));
355: packet_encrypt(&send_context, cp, buffer_ptr(&outgoing_packet),
356: buffer_len(&outgoing_packet));
357:
358: #ifdef PACKET_DEBUG
359: fprintf(stderr, "encrypted: "); buffer_dump(&output);
360: #endif
361:
362: buffer_clear(&outgoing_packet);
363:
364: /* Note that the packet is now only buffered in output. It won\'t be
365: actually sent until packet_write_wait or packet_write_poll is called. */
366: }
367:
368: /* Waits until a packet has been received, and returns its type. Note that
369: no other data is processed until this returns, so this function should
370: not be used during the interactive session. */
371:
1.2 provos 372: int
373: packet_read(int *payload_len_ptr)
1.1 deraadt 374: {
375: int type, len;
376: fd_set set;
377: char buf[8192];
378:
379: /* Since we are blocking, ensure that all written packets have been sent. */
380: packet_write_wait();
381:
382: /* Stay in the loop until we have received a complete packet. */
383: for (;;)
384: {
385: /* Try to read a packet from the buffer. */
386: type = packet_read_poll(payload_len_ptr);
387: if (type == SSH_SMSG_SUCCESS
388: || type == SSH_SMSG_FAILURE
389: || type == SSH_CMSG_EOF
390: || type == SSH_CMSG_EXIT_CONFIRMATION)
391: packet_integrity_check(*payload_len_ptr, 0, type);
392: /* If we got a packet, return it. */
393: if (type != SSH_MSG_NONE)
394: return type;
395: /* Otherwise, wait for some data to arrive, add it to the buffer,
396: and try again. */
397: FD_ZERO(&set);
398: FD_SET(connection_in, &set);
399: /* Wait for some data to arrive. */
400: select(connection_in + 1, &set, NULL, NULL, NULL);
401: /* Read data from the socket. */
402: len = read(connection_in, buf, sizeof(buf));
403: if (len == 0)
404: fatal("Connection closed by remote host.");
405: if (len < 0)
406: fatal("Read from socket failed: %.100s", strerror(errno));
407: /* Append it to the buffer. */
408: packet_process_incoming(buf, len);
409: }
410: /*NOTREACHED*/
411: }
412:
413: /* Waits until a packet has been received, verifies that its type matches
414: that given, and gives a fatal error and exits if there is a mismatch. */
415:
1.2 provos 416: void
417: packet_read_expect(int *payload_len_ptr, int expected_type)
1.1 deraadt 418: {
419: int type;
420:
421: type = packet_read(payload_len_ptr);
422: if (type != expected_type)
423: packet_disconnect("Protocol error: expected packet type %d, got %d",
424: expected_type, type);
425: }
426:
427: /* Checks if a full packet is available in the data received so far via
428: packet_process_incoming. If so, reads the packet; otherwise returns
429: SSH_MSG_NONE. This does not wait for data from the connection.
430:
431: SSH_MSG_DISCONNECT is handled specially here. Also,
432: SSH_MSG_IGNORE messages are skipped by this function and are never returned
433: to higher levels.
434:
435: The returned payload_len does include space consumed by:
436: Packet length
437: Padding
438: Packet type
439: Check bytes
440:
441:
442: */
443:
1.2 provos 444: int
445: packet_read_poll(int *payload_len_ptr)
1.1 deraadt 446: {
447: unsigned int len, padded_len;
448: unsigned char *ucp;
449: char buf[8], *cp;
450: unsigned long checksum, stored_checksum;
451:
452: restart:
453:
454: /* Check if input size is less than minimum packet size. */
455: if (buffer_len(&input) < 4 + 8)
456: return SSH_MSG_NONE;
457: /* Get length of incoming packet. */
458: ucp = (unsigned char *)buffer_ptr(&input);
459: len = GET_32BIT(ucp);
460: if (len < 1 + 2 + 2 || len > 256*1024)
461: packet_disconnect("Bad packet length %d.", len);
462: padded_len = (len + 8) & ~7;
463:
464: /* Check if the packet has been entirely received. */
465: if (buffer_len(&input) < 4 + padded_len)
466: return SSH_MSG_NONE;
467:
468: /* The entire packet is in buffer. */
469:
470: /* Consume packet length. */
471: buffer_consume(&input, 4);
472:
473: /* Copy data to incoming_packet. */
474: buffer_clear(&incoming_packet);
475: buffer_append_space(&incoming_packet, &cp, padded_len);
476: packet_decrypt(&receive_context, cp, buffer_ptr(&input), padded_len);
477: buffer_consume(&input, padded_len);
478:
479: #ifdef PACKET_DEBUG
480: fprintf(stderr, "read_poll plain: "); buffer_dump(&incoming_packet);
481: #endif
482:
483: /* Compute packet checksum. */
484: checksum = crc32((unsigned char *)buffer_ptr(&incoming_packet),
485: buffer_len(&incoming_packet) - 4);
486:
487: /* Skip padding. */
488: buffer_consume(&incoming_packet, 8 - len % 8);
489:
490: /* Test check bytes. */
491: assert(len == buffer_len(&incoming_packet));
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: #ifdef IPTOS_LOWDELAY
726: int lowdelay = IPTOS_LOWDELAY;
727: if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *)&lowdelay,
728: sizeof(lowdelay)) < 0)
729: error("setsockopt IPTOS_LOWDELAY: %.100s", strerror(errno));
730: #endif /* IPTOS_LOWDELAY */
731: if (setsockopt(connection_in, IPPROTO_TCP, TCP_NODELAY, (void *)&on,
732: sizeof(on)) < 0)
733: error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
734: }
735: else
736: {
737: /* Set IP options for a non-interactive connection. Use
738: IPTOS_THROUGHPUT. */
739: #ifdef IPTOS_THROUGHPUT
740: int throughput = IPTOS_THROUGHPUT;
741: if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *)&throughput,
742: sizeof(throughput)) < 0)
743: error("setsockopt IPTOS_THROUGHPUT: %.100s", strerror(errno));
744: #endif /* IPTOS_THROUGHPUT */
745: }
746: }
747:
748: /* Returns true if the current connection is interactive. */
749:
1.2 provos 750: int
751: packet_is_interactive()
1.1 deraadt 752: {
753: return interactive_mode;
754: }
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