2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 static const char sccsid[] = "@(#)enc_des.c 8.3 (Berkeley) 5/30/95";
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
43 # ifdef AUTHENTICATION
44 #include <arpa/telnet.h>
45 #include <openssl/des.h>
51 #include "key-proto.h"
52 #include "misc-proto.h"
54 extern int encrypt_debug_mode;
62 #define IN_PROGRESS (NO_SEND_IV|NO_RECV_IV|NO_KEYID)
69 Schedule krbdes_sched;
71 unsigned char fb_feed[64];
86 static struct fb fb[2];
95 { "\0", 1, 0, 0, 0 }, /* default key of zero */
99 #define KEYFLAG_MASK 03
101 #define KEYFLAG_NOINIT 00
102 #define KEYFLAG_INIT 01
103 #define KEYFLAG_OK 02
104 #define KEYFLAG_BAD 03
106 #define KEYFLAG_SHIFT 2
108 #define SHIFT_VAL(a,b) (KEYFLAG_SHIFT*((a)+((b)*2)))
112 #define FB64_IV_BAD 3
115 void fb64_stream_iv(Block, struct stinfo *);
116 void fb64_init(struct fb *);
117 static int fb64_start(struct fb *, int, int);
118 int fb64_is(unsigned char *, int, struct fb *);
119 int fb64_reply(unsigned char *, int, struct fb *);
120 static void fb64_session(Session_Key *, int, struct fb *);
121 void fb64_stream_key(Block, struct stinfo *);
122 int fb64_keyid(int, unsigned char *, int *, struct fb *);
125 cfb64_init(int server __unused)
128 fb[CFB].fb_feed[4] = ENCTYPE_DES_CFB64;
129 fb[CFB].streams[0].str_flagshift = SHIFT_VAL(0, CFB);
130 fb[CFB].streams[1].str_flagshift = SHIFT_VAL(1, CFB);
134 ofb64_init(int server __unused)
137 fb[OFB].fb_feed[4] = ENCTYPE_DES_OFB64;
138 fb[CFB].streams[0].str_flagshift = SHIFT_VAL(0, OFB);
139 fb[CFB].streams[1].str_flagshift = SHIFT_VAL(1, OFB);
143 fb64_init(struct fb *fbp)
145 memset((void *)fbp, 0, sizeof(*fbp));
146 fbp->state[0] = fbp->state[1] = FAILED;
147 fbp->fb_feed[0] = IAC;
148 fbp->fb_feed[1] = SB;
149 fbp->fb_feed[2] = TELOPT_ENCRYPT;
150 fbp->fb_feed[3] = ENCRYPT_IS;
155 * -1: some error. Negotiation is done, encryption not ready.
156 * 0: Successful, initial negotiation all done.
157 * 1: successful, negotiation not done yet.
158 * 2: Not yet. Other things (like getting the key from
159 * Kerberos) have to happen before we can continue.
162 cfb64_start(int dir, int server)
164 return(fb64_start(&fb[CFB], dir, server));
168 ofb64_start(int dir, int server)
170 return(fb64_start(&fb[OFB], dir, server));
174 fb64_start(struct fb *fbp, int dir, int server __unused)
183 * This is simply a request to have the other side
184 * start output (our input). He will negotiate an
185 * IV so we need not look for it.
187 state = fbp->state[dir-1];
193 state = fbp->state[dir-1];
196 else if ((state & NO_SEND_IV) == 0)
199 if (!VALIDKEY(fbp->krbdes_key)) {
203 state &= ~NO_SEND_IV;
205 if (encrypt_debug_mode)
206 printf("Creating new feed\r\n");
208 * Create a random feed and send it over.
210 des_random_key((Block *)fbp->temp_feed);
211 des_ecb_encrypt((Block *)fbp->temp_feed, (Block *)fbp->temp_feed,
212 fbp->krbdes_sched, 1);
213 p = fbp->fb_feed + 3;
217 for (x = 0; x < sizeof(Block); ++x) {
218 if ((*p++ = fbp->temp_feed[x]) == IAC)
223 printsub('>', &fbp->fb_feed[2], p - &fbp->fb_feed[2]);
224 net_write(fbp->fb_feed, p - fbp->fb_feed);
229 return(fbp->state[dir-1] = state);
234 * -1: some error. Negotiation is done, encryption not ready.
235 * 0: Successful, initial negotiation all done.
236 * 1: successful, negotiation not done yet.
239 cfb64_is(unsigned char *data, int cnt)
241 return(fb64_is(data, cnt, &fb[CFB]));
245 ofb64_is(unsigned char *data, int cnt)
247 return(fb64_is(data, cnt, &fb[OFB]));
251 fb64_is(unsigned char *data, int cnt, struct fb *fbp)
254 int state = fbp->state[DIR_DECRYPT-1];
261 if (cnt != sizeof(Block)) {
262 if (encrypt_debug_mode)
263 printf("CFB64: initial vector failed on size\r\n");
268 if (encrypt_debug_mode)
269 printf("CFB64: initial vector received\r\n");
271 if (encrypt_debug_mode)
272 printf("Initializing Decrypt stream\r\n");
274 fb64_stream_iv((void *)data, &fbp->streams[DIR_DECRYPT-1]);
276 p = fbp->fb_feed + 3;
277 *p++ = ENCRYPT_REPLY;
282 printsub('>', &fbp->fb_feed[2], p - &fbp->fb_feed[2]);
283 net_write(fbp->fb_feed, p - fbp->fb_feed);
285 state = fbp->state[DIR_DECRYPT-1] = IN_PROGRESS;
289 if (encrypt_debug_mode) {
290 printf("Unknown option type: %d\r\n", *(data-1));
297 * We failed. Send an FB64_IV_BAD option
298 * to the other side so it will know that
301 p = fbp->fb_feed + 3;
302 *p++ = ENCRYPT_REPLY;
307 printsub('>', &fbp->fb_feed[2], p - &fbp->fb_feed[2]);
308 net_write(fbp->fb_feed, p - fbp->fb_feed);
312 return(fbp->state[DIR_DECRYPT-1] = state);
317 * -1: some error. Negotiation is done, encryption not ready.
318 * 0: Successful, initial negotiation all done.
319 * 1: successful, negotiation not done yet.
322 cfb64_reply(unsigned char *data, int cnt)
324 return(fb64_reply(data, cnt, &fb[CFB]));
328 ofb64_reply(unsigned char *data, int cnt)
330 return(fb64_reply(data, cnt, &fb[OFB]));
334 fb64_reply(unsigned char *data, int cnt, struct fb *fbp)
336 int state = fbp->state[DIR_ENCRYPT-1];
343 fb64_stream_iv(fbp->temp_feed, &fbp->streams[DIR_ENCRYPT-1]);
346 state &= ~NO_RECV_IV;
347 encrypt_send_keyid(DIR_ENCRYPT, "\0", 1, 1);
351 memset(fbp->temp_feed, 0, sizeof(Block));
352 fb64_stream_iv(fbp->temp_feed, &fbp->streams[DIR_ENCRYPT-1]);
357 if (encrypt_debug_mode) {
358 printf("Unknown option type: %d\r\n", data[-1]);
367 return(fbp->state[DIR_ENCRYPT-1] = state);
371 cfb64_session(Session_Key *key, int server)
373 fb64_session(key, server, &fb[CFB]);
377 ofb64_session(Session_Key *key, int server)
379 fb64_session(key, server, &fb[OFB]);
383 fb64_session(Session_Key *key, int server, struct fb *fbp)
385 if (!key || key->type != SK_DES) {
386 if (encrypt_debug_mode)
387 printf("Can't set krbdes's session key (%d != %d)\r\n",
388 key ? key->type : -1, SK_DES);
391 memmove((void *)fbp->krbdes_key, (void *)key->data, sizeof(Block));
393 fb64_stream_key(fbp->krbdes_key, &fbp->streams[DIR_ENCRYPT-1]);
394 fb64_stream_key(fbp->krbdes_key, &fbp->streams[DIR_DECRYPT-1]);
396 des_key_sched((Block *)fbp->krbdes_key, fbp->krbdes_sched);
398 * Now look to see if krbdes_start() was was waiting for
399 * the key to show up. If so, go ahead an call it now
400 * that we have the key.
402 if (fbp->need_start) {
404 fb64_start(fbp, DIR_ENCRYPT, server);
409 * We only accept a keyid of 0. If we get a keyid of
410 * 0, then mark the state as SUCCESS.
413 cfb64_keyid(int dir, unsigned char *kp, int *lenp)
415 return(fb64_keyid(dir, kp, lenp, &fb[CFB]));
419 ofb64_keyid(int dir, unsigned char *kp, int *lenp)
421 return(fb64_keyid(dir, kp, lenp, &fb[OFB]));
425 fb64_keyid(int dir, unsigned char *kp, int *lenp, struct fb *fbp)
427 int state = fbp->state[dir-1];
429 if (*lenp != 1 || (*kp != '\0')) {
439 return(fbp->state[dir-1] = state);
443 fb64_printsub(unsigned char *data, int cnt, unsigned char *buf, int buflen, const char *type)
449 buf[buflen-1] = '\0'; /* make sure it's NULL terminated */
454 sprintf(lbuf, "%s_IV", type);
459 sprintf(lbuf, "%s_IV_OK", type);
464 sprintf(lbuf, "%s_IV_BAD", type);
469 sprintf(lbuf, " %d (unknown)", data[2]);
472 for (; (buflen > 0) && (*buf = *cp++); buf++)
474 for (i = 3; i < cnt; i++) {
475 sprintf(lbuf, " %d", data[i]);
476 for (cp = lbuf; (buflen > 0) && (*buf = *cp++); buf++)
484 cfb64_printsub(unsigned char *data, int cnt, unsigned char *buf, int buflen)
486 fb64_printsub(data, cnt, buf, buflen, "CFB64");
490 ofb64_printsub(unsigned char *data, int cnt, unsigned char *buf, int buflen)
492 fb64_printsub(data, cnt, buf, buflen, "OFB64");
496 fb64_stream_iv(Block seed, struct stinfo *stp)
499 memmove((void *)stp->str_iv, (void *)seed, sizeof(Block));
500 memmove((void *)stp->str_output, (void *)seed, sizeof(Block));
502 des_key_sched((Block *)stp->str_ikey, stp->str_sched);
504 stp->str_index = sizeof(Block);
508 fb64_stream_key(Block key, struct stinfo *stp)
510 memmove((void *)stp->str_ikey, (void *)key, sizeof(Block));
511 des_key_sched((Block *)key, stp->str_sched);
513 memmove((void *)stp->str_output, (void *)stp->str_iv, sizeof(Block));
515 stp->str_index = sizeof(Block);
519 * DES 64 bit Cipher Feedback
525 * INPUT --(--------->(+)+---> DATA
531 * iV: Initial vector, 64 bits (8 bytes) long.
532 * Dn: the nth chunk of 64 bits (8 bytes) of data to encrypt (decrypt).
533 * On: the nth chunk of 64 bits (8 bytes) of encrypted (decrypted) output.
537 * V(n+1) = DES(On, key)
541 cfb64_encrypt(unsigned char *s, int c)
543 struct stinfo *stp = &fb[CFB].streams[DIR_ENCRYPT-1];
546 idx = stp->str_index;
548 if (idx == sizeof(Block)) {
550 des_ecb_encrypt((Block *)stp->str_output, (Block *)b, stp->str_sched, 1);
551 memmove((void *)stp->str_feed, (void *)b, sizeof(Block));
555 /* On encryption, we store (feed ^ data) which is cypher */
556 *s = stp->str_output[idx] = (stp->str_feed[idx] ^ *s);
560 stp->str_index = idx;
564 cfb64_decrypt(int data)
566 struct stinfo *stp = &fb[CFB].streams[DIR_DECRYPT-1];
571 * Back up one byte. It is assumed that we will
572 * never back up more than one byte. If we do, this
573 * may or may not work.
580 idx = stp->str_index++;
581 if (idx == sizeof(Block)) {
583 des_ecb_encrypt((Block *)stp->str_output, (Block *)b, stp->str_sched, 1);
584 memmove((void *)stp->str_feed, (void *)b, sizeof(Block));
585 stp->str_index = 1; /* Next time will be 1 */
586 idx = 0; /* But now use 0 */
589 /* On decryption we store (data) which is cypher. */
590 stp->str_output[idx] = data;
591 return(data ^ stp->str_feed[idx]);
595 * DES 64 bit Output Feedback
602 * INPUT -------->(+) ----> DATA
605 * iV: Initial vector, 64 bits (8 bytes) long.
606 * Dn: the nth chunk of 64 bits (8 bytes) of data to encrypt (decrypt).
607 * On: the nth chunk of 64 bits (8 bytes) of encrypted (decrypted) output.
610 * V(n+1) = DES(Vn, key)
614 ofb64_encrypt(unsigned char *s, int c)
616 struct stinfo *stp = &fb[OFB].streams[DIR_ENCRYPT-1];
619 idx = stp->str_index;
621 if (idx == sizeof(Block)) {
623 des_ecb_encrypt((Block *)stp->str_feed, (Block *)b, stp->str_sched, 1);
624 memmove((void *)stp->str_feed, (void *)b, sizeof(Block));
627 *s++ ^= stp->str_feed[idx];
630 stp->str_index = idx;
634 ofb64_decrypt(int data)
636 struct stinfo *stp = &fb[OFB].streams[DIR_DECRYPT-1];
641 * Back up one byte. It is assumed that we will
642 * never back up more than one byte. If we do, this
643 * may or may not work.
650 idx = stp->str_index++;
651 if (idx == sizeof(Block)) {
653 des_ecb_encrypt((Block *)stp->str_feed, (Block *)b, stp->str_sched, 1);
654 memmove((void *)stp->str_feed, (void *)b, sizeof(Block));
655 stp->str_index = 1; /* Next time will be 1 */
656 idx = 0; /* But now use 0 */
659 return(data ^ stp->str_feed[idx]);
661 # endif /* AUTHENTICATION */
662 #endif /* ENCRYPTION */