bdes.c revision 63249
1/*-
2 * Copyright (c) 1991, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Matt Bishop of Dartmouth College.
7 *
8 * The United States Government has rights in this work pursuant
9 * to contract no. NAG 2-680 between the National Aeronautics and
10 * Space Administration and Dartmouth College.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 *    must display the following acknowledgement:
22 *	This product includes software developed by the University of
23 *	California, Berkeley and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 *    may be used to endorse or promote products derived from this software
26 *    without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 */
40
41#ifndef lint
42static char copyright[] =
43"@(#) Copyright (c) 1991, 1993\n\
44	The Regents of the University of California.  All rights reserved.\n";
45#endif /* not lint */
46
47#ifndef lint
48#if 0
49static char sccsid[] = "@(#)bdes.c	8.1 (Berkeley) 6/6/93";
50#else
51static const char rcsid[] =
52 "$FreeBSD: head/secure/usr.bin/bdes/bdes.c 63248 2000-07-16 05:48:49Z peter $";
53#endif
54#endif /* not lint */
55
56/*
57 * BDES -- DES encryption package for Berkeley Software Distribution 4.4
58 * options:
59 *	-a	key is in ASCII
60 *	-b	use ECB (electronic code book) mode
61 *	-d	invert (decrypt) input
62 *	-f b	use b-bit CFB (cipher feedback) mode
63 *	-F b	use b-bit CFB (cipher feedback) alternative mode
64 *	-k key	use key as the cryptographic key
65 *	-m b	generate a MAC of length b
66 *	-o b	use b-bit OFB (output feedback) mode
67 *	-p	don't reset the parity bit
68 *	-v v	use v as the initialization vector (ignored for ECB)
69 * note: the last character of the last block is the integer indicating
70 * how many characters of that block are to be output
71 *
72 * Author: Matt Bishop
73 *	   Department of Mathematics and Computer Science
74 *	   Dartmouth College
75 *	   Hanover, NH  03755
76 * Email:  Matt.Bishop@dartmouth.edu
77 *	   ...!decvax!dartvax!Matt.Bishop
78 *
79 * See Technical Report PCS-TR91-158, Department of Mathematics and Computer
80 * Science, Dartmouth College, for a detailed description of the implemen-
81 * tation and differences between it and Sun's.  The DES is described in
82 * FIPS PUB 46, and the modes in FIPS PUB 81 (see either the manual page
83 * or the technical report for a complete reference).
84 */
85
86#include <errno.h>
87#include <unistd.h>
88#include <stdio.h>
89#include <ctype.h>
90#include <stdlib.h>
91#include <string.h>
92
93/*
94 * BSD and System V systems offer special library calls that do
95 * block moves and fills, so if possible we take advantage of them
96 */
97#define	MEMCPY(dest,src,len)	bcopy((src),(dest),(len))
98#define	MEMZERO(dest,len)	bzero((dest),(len))
99
100/* Hide the calls to the primitive encryption routines. */
101#define	FASTWAY
102#ifdef	FASTWAY
103#define	DES_KEY(buf) \
104	if (des_setkey(buf)) \
105		err("des_setkey", 0);
106#define	DES_XFORM(buf) \
107	if (des_cipher(buf, buf, 0L, (inverse ? -1 : 1))) \
108		err("des_cipher", 0);
109#else
110#define	DES_KEY(buf)	{						\
111				char bits1[64];	/* bits of key */	\
112				expand(buf, bits1);			\
113				if (setkey(bits1))			\
114					err("setkey", 0);		\
115			}
116#define	DES_XFORM(buf)	{						\
117				char bits1[64];	/* bits of message */	\
118				expand(buf, bits1);			\
119				if (encrypt(bits1, inverse))		\
120					err("encrypt", 0);		\
121				compress(bits1, buf);			\
122			}
123#endif
124
125/*
126 * this does an error-checking write
127 */
128#define	READ(buf, n)	fread(buf, sizeof(char), n, stdin)
129#define WRITE(buf,n)						\
130		if (fwrite(buf, sizeof(char), n, stdout) != n)	\
131			err(bn, NULL);
132
133/*
134 * some things to make references easier
135 */
136typedef char Desbuf[8];
137#define	CHAR(x,i)	(x[i])
138#define	UCHAR(x,i)	(x[i])
139#define	BUFFER(x)	(x)
140#define	UBUFFER(x)	(x)
141
142/*
143 * global variables and related macros
144 */
145#define KEY_DEFAULT		0	/* interpret radix of key from key */
146#define KEY_ASCII		1	/* key is in ASCII characters */
147int keybase = KEY_DEFAULT;		/* how to interpret the key */
148
149enum { 					/* encrypt, decrypt, authenticate */
150	MODE_ENCRYPT, MODE_DECRYPT, MODE_AUTHENTICATE
151} mode = MODE_ENCRYPT;
152enum {					/* ecb, cbc, cfb, cfba, ofb? */
153	ALG_ECB, ALG_CBC, ALG_CFB, ALG_OFB, ALG_CFBA
154} alg = ALG_CBC;
155
156Desbuf ivec;				/* initialization vector */
157char bits[] = {				/* used to extract bits from a char */
158	'\200', '\100', '\040', '\020', '\010', '\004', '\002', '\001'
159};
160int inverse;				/* 0 to encrypt, 1 to decrypt */
161int macbits = -1;			/* number of bits in authentication */
162int fbbits = -1;			/* number of feedback bits */
163int pflag;				/* 1 to preserve parity bits */
164
165main(ac, av)
166	int ac;				/* arg count */
167	char **av;			/* arg vector */
168{
169	extern int optind;		/* option (argument) number */
170	extern char *optarg;		/* argument to option if any */
171	register int i;			/* counter in a for loop */
172	register char *p;		/* used to obtain the key */
173	Desbuf msgbuf;			/* I/O buffer */
174	int kflag;			/* command-line encryptiooon key */
175	int argc;			/* the real arg count */
176	char **argv;			/* the real argument vector */
177
178	/*
179	 * Hide the arguments from ps(1) by making private copies of them
180	 * and clobbering the global (visible to ps(1)) ones.
181	 */
182	argc = ac;
183	ac = 1;
184	argv = malloc((argc + 1) * sizeof(char *));
185	for (i = 0; i < argc; ++i) {
186		argv[i] = strdup(av[i]);
187		MEMZERO(av[i], strlen(av[i]));
188	}
189	argv[argc] = NULL;
190
191	/* initialize the initialization vctor */
192	MEMZERO(ivec, 8);
193
194	/* process the argument list */
195	kflag = 0;
196	while ((i = getopt(argc, argv, "abdF:f:k:m:o:pv:")) != EOF)
197		switch(i) {
198		case 'a':		/* key is ASCII */
199			keybase = KEY_ASCII;
200			break;
201		case 'b':		/* use ECB mode */
202			alg = ALG_ECB;
203			break;
204		case 'd':		/* decrypt */
205			mode = MODE_DECRYPT;
206			break;
207		case 'F':		/* use alternative CFB mode */
208			alg = ALG_CFBA;
209			if ((fbbits = setbits(optarg, 7)) > 56 || fbbits == 0)
210				err(-1, "-F: number must be 1-56 inclusive");
211			else if (fbbits == -1)
212				err(-1, "-F: number must be a multiple of 7");
213			break;
214		case 'f':		/* use CFB mode */
215			alg = ALG_CFB;
216			if ((fbbits = setbits(optarg, 8)) > 64 || fbbits == 0)
217				err(-1, "-f: number must be 1-64 inclusive");
218			else if (fbbits == -1)
219				err(-1, "-f: number must be a multiple of 8");
220			break;
221		case 'k':		/* encryption key */
222			kflag = 1;
223			cvtkey(BUFFER(msgbuf), optarg);
224			break;
225		case 'm':		/* number of bits for MACing */
226			mode = MODE_AUTHENTICATE;
227			if ((macbits = setbits(optarg, 1)) > 64)
228				err(-1, "-m: number must be 0-64 inclusive");
229			break;
230		case 'o':		/* use OFB mode */
231			alg = ALG_OFB;
232			if ((fbbits = setbits(optarg, 8)) > 64 || fbbits == 0)
233				err(-1, "-o: number must be 1-64 inclusive");
234			else if (fbbits == -1)
235				err(-1, "-o: number must be a multiple of 8");
236			break;
237		case 'p':		/* preserve parity bits */
238			pflag = 1;
239			break;
240		case 'v':		/* set initialization vector */
241			cvtkey(BUFFER(ivec), optarg);
242			break;
243		default:		/* error */
244			usage();
245		}
246
247	if (!kflag) {
248		/*
249		 * if the key's not ASCII, assume it is
250		 */
251		keybase = KEY_ASCII;
252		/*
253		 * get the key
254		 */
255		p = getpass("Enter key: ");
256		/*
257		 * copy it, nul-padded, into the key area
258		 */
259		cvtkey(BUFFER(msgbuf), p);
260	}
261
262	makekey(msgbuf);
263	inverse = (alg == ALG_CBC || alg == ALG_ECB) && mode == MODE_DECRYPT;
264
265	switch(alg) {
266	case ALG_CBC:
267		switch(mode) {
268		case MODE_AUTHENTICATE:	/* authenticate using CBC mode */
269			cbcauth();
270			break;
271		case MODE_DECRYPT:	/* decrypt using CBC mode */
272			cbcdec();
273			break;
274		case MODE_ENCRYPT:	/* encrypt using CBC mode */
275			cbcenc();
276			break;
277		}
278		break;
279	case ALG_CFB:
280		switch(mode) {
281		case MODE_AUTHENTICATE:	/* authenticate using CFB mode */
282			cfbauth();
283			break;
284		case MODE_DECRYPT:	/* decrypt using CFB mode */
285			cfbdec();
286			break;
287		case MODE_ENCRYPT:	/* encrypt using CFB mode */
288			cfbenc();
289			break;
290		}
291		break;
292	case ALG_CFBA:
293		switch(mode) {
294		case MODE_AUTHENTICATE:	/* authenticate using CFBA mode */
295			err(-1, "can't authenticate with CFBA mode");
296			break;
297		case MODE_DECRYPT:	/* decrypt using CFBA mode */
298			cfbadec();
299			break;
300		case MODE_ENCRYPT:	/* encrypt using CFBA mode */
301			cfbaenc();
302			break;
303		}
304		break;
305	case ALG_ECB:
306		switch(mode) {
307		case MODE_AUTHENTICATE:	/* authenticate using ECB mode */
308			err(-1, "can't authenticate with ECB mode");
309			break;
310		case MODE_DECRYPT:	/* decrypt using ECB mode */
311			ecbdec();
312			break;
313		case MODE_ENCRYPT:	/* encrypt using ECB mode */
314			ecbenc();
315			break;
316		}
317		break;
318	case ALG_OFB:
319		switch(mode) {
320		case MODE_AUTHENTICATE:	/* authenticate using OFB mode */
321			err(-1, "can't authenticate with OFB mode");
322			break;
323		case MODE_DECRYPT:	/* decrypt using OFB mode */
324			ofbdec();
325			break;
326		case MODE_ENCRYPT:	/* encrypt using OFB mode */
327			ofbenc();
328			break;
329		}
330		break;
331	}
332	exit(0);
333}
334
335/*
336 * print a warning message and, possibly, terminate
337 */
338err(n, s)
339	int n;			/* offending block number */
340	char *s;		/* the message */
341{
342	if (n > 0)
343		(void)fprintf(stderr, "bdes (block %d): ", n);
344	else
345		(void)fprintf(stderr, "bdes: ");
346	(void)fprintf(stderr, "%s\n", s ? s : strerror(errno));
347	exit(1);
348}
349
350/*
351 * map a hex character to an integer
352 */
353tobinhex(c, radix)
354	char c;			/* char to be converted */
355	int radix;		/* base (2 to 16) */
356{
357	switch(c) {
358	case '0':		return(0x0);
359	case '1':		return(0x1);
360	case '2':		return(radix > 2 ? 0x2 : -1);
361	case '3':		return(radix > 3 ? 0x3 : -1);
362	case '4':		return(radix > 4 ? 0x4 : -1);
363	case '5':		return(radix > 5 ? 0x5 : -1);
364	case '6':		return(radix > 6 ? 0x6 : -1);
365	case '7':		return(radix > 7 ? 0x7 : -1);
366	case '8':		return(radix > 8 ? 0x8 : -1);
367	case '9':		return(radix > 9 ? 0x9 : -1);
368	case 'A': case 'a':	return(radix > 10 ? 0xa : -1);
369	case 'B': case 'b':	return(radix > 11 ? 0xb : -1);
370	case 'C': case 'c':	return(radix > 12 ? 0xc : -1);
371	case 'D': case 'd':	return(radix > 13 ? 0xd : -1);
372	case 'E': case 'e':	return(radix > 14 ? 0xe : -1);
373	case 'F': case 'f':	return(radix > 15 ? 0xf : -1);
374	}
375	/*
376	 * invalid character
377	 */
378	return(-1);
379}
380
381/*
382 * convert the key to a bit pattern
383 */
384cvtkey(obuf, ibuf)
385	char *obuf;			/* bit pattern */
386	char *ibuf;			/* the key itself */
387{
388	register int i, j;		/* counter in a for loop */
389	int nbuf[64];			/* used for hex/key translation */
390
391	/*
392	 * just switch on the key base
393	 */
394	switch(keybase) {
395	case KEY_ASCII:			/* ascii to integer */
396		(void)strncpy(obuf, ibuf, 8);
397		return;
398	case KEY_DEFAULT:		/* tell from context */
399		/*
400		 * leading '0x' or '0X' == hex key
401		 */
402		if (ibuf[0] == '0' && (ibuf[1] == 'x' || ibuf[1] == 'X')) {
403			ibuf = &ibuf[2];
404			/*
405			 * now translate it, bombing on any illegal hex digit
406			 */
407			for (i = 0; ibuf[i] && i < 16; i++)
408				if ((nbuf[i] = tobinhex(ibuf[i], 16)) == -1)
409					err(-1, "bad hex digit in key");
410			while (i < 16)
411				nbuf[i++] = 0;
412			for (i = 0; i < 8; i++)
413				obuf[i] =
414				    ((nbuf[2*i]&0xf)<<4) | (nbuf[2*i+1]&0xf);
415			/* preserve parity bits */
416			pflag = 1;
417			return;
418		}
419		/*
420		 * leading '0b' or '0B' == binary key
421		 */
422		if (ibuf[0] == '0' && (ibuf[1] == 'b' || ibuf[1] == 'B')) {
423			ibuf = &ibuf[2];
424			/*
425			 * now translate it, bombing on any illegal binary digit
426			 */
427			for (i = 0; ibuf[i] && i < 16; i++)
428				if ((nbuf[i] = tobinhex(ibuf[i], 2)) == -1)
429					err(-1, "bad binary digit in key");
430			while (i < 64)
431				nbuf[i++] = 0;
432			for (i = 0; i < 8; i++)
433				for (j = 0; j < 8; j++)
434					obuf[i] = (obuf[i]<<1)|nbuf[8*i+j];
435			/* preserve parity bits */
436			pflag = 1;
437			return;
438		}
439		/*
440		 * no special leader -- ASCII
441		 */
442		(void)strncpy(obuf, ibuf, 8);
443	}
444}
445
446/*
447 * convert an ASCII string into a decimal number:
448 * 1. must be between 0 and 64 inclusive
449 * 2. must be a valid decimal number
450 * 3. must be a multiple of mult
451 */
452setbits(s, mult)
453	char *s;			/* the ASCII string */
454	int mult;			/* what it must be a multiple of */
455{
456	register char *p;		/* pointer in a for loop */
457	register int n = 0;		/* the integer collected */
458
459	/*
460	 * skip white space
461	 */
462	while (isspace(*s))
463		s++;
464	/*
465	 * get the integer
466	 */
467	for (p = s; *p; p++) {
468		if (isdigit(*p))
469			n = n * 10 + *p - '0';
470		else {
471			err(-1, "bad decimal digit in MAC length");
472		}
473	}
474	/*
475	 * be sure it's a multiple of mult
476	 */
477	return((n % mult != 0) ? -1 : n);
478}
479
480/*****************
481 * DES FUNCTIONS *
482 *****************/
483/*
484 * This sets the DES key and (if you're using the deszip version)
485 * the direction of the transformation.  This uses the Sun
486 * to map the 64-bit key onto the 56 bits that the key schedule
487 * generation routines use: the old way, which just uses the user-
488 * supplied 64 bits as is, and the new way, which resets the parity
489 * bit to be the same as the low-order bit in each character.  The
490 * new way generates a greater variety of key schedules, since many
491 * systems set the parity (high) bit of each character to 0, and the
492 * DES ignores the low order bit of each character.
493 */
494makekey(buf)
495	Desbuf buf;				/* key block */
496{
497	register int i, j;			/* counter in a for loop */
498	register int par;			/* parity counter */
499
500	/*
501	 * if the parity is not preserved, flip it
502	 */
503	if (!pflag) {
504		for (i = 0; i < 8; i++) {
505			par = 0;
506			for (j = 1; j < 8; j++)
507				if ((bits[j]&UCHAR(buf, i)) != 0)
508					par++;
509			if ((par&01) == 01)
510				UCHAR(buf, i) = UCHAR(buf, i)&0177;
511			else
512				UCHAR(buf, i) = (UCHAR(buf, i)&0177)|0200;
513		}
514	}
515
516	DES_KEY(UBUFFER(buf));
517}
518
519/*
520 * This encrypts using the Electronic Code Book mode of DES
521 */
522ecbenc()
523{
524	register int n;		/* number of bytes actually read */
525	register int bn;	/* block number */
526	Desbuf msgbuf;		/* I/O buffer */
527
528	for (bn = 0; (n = READ(BUFFER(msgbuf),  8)) == 8; bn++) {
529		/*
530		 * do the transformation
531		 */
532		DES_XFORM(UBUFFER(msgbuf));
533		WRITE(BUFFER(msgbuf), 8);
534	}
535	/*
536	 * at EOF or last block -- in either case, the last byte contains
537	 * the character representation of the number of bytes in it
538	 */
539	bn++;
540	MEMZERO(&CHAR(msgbuf, n), 8 - n);
541	CHAR(msgbuf, 7) = n;
542	DES_XFORM(UBUFFER(msgbuf));
543	WRITE(BUFFER(msgbuf), 8);
544
545}
546
547/*
548 * This decrypts using the Electronic Code Book mode of DES
549 */
550ecbdec()
551{
552	register int n;		/* number of bytes actually read */
553	register int c;		/* used to test for EOF */
554	register int bn;	/* block number */
555	Desbuf msgbuf;		/* I/O buffer */
556
557	for (bn = 1; (n = READ(BUFFER(msgbuf), 8)) == 8; bn++) {
558		/*
559		 * do the transformation
560		 */
561		DES_XFORM(UBUFFER(msgbuf));
562		/*
563		 * if the last one, handle it specially
564		 */
565		if ((c = getchar()) == EOF) {
566			n = CHAR(msgbuf, 7);
567			if (n < 0 || n > 7)
568				err(bn, "decryption failed (block corrupted)");
569		}
570		else
571			(void)ungetc(c, stdin);
572		WRITE(BUFFER(msgbuf), n);
573	}
574	if (n > 0)
575		err(bn, "decryption failed (incomplete block)");
576}
577
578/*
579 * This encrypts using the Cipher Block Chaining mode of DES
580 */
581cbcenc()
582{
583	register int n;		/* number of bytes actually read */
584	register int bn;	/* block number */
585	Desbuf msgbuf;		/* I/O buffer */
586
587	/*
588	 * do the transformation
589	 */
590	for (bn = 1; (n = READ(BUFFER(msgbuf), 8)) == 8; bn++) {
591		for (n = 0; n < 8; n++)
592			CHAR(msgbuf, n) ^= CHAR(ivec, n);
593		DES_XFORM(UBUFFER(msgbuf));
594		MEMCPY(BUFFER(ivec), BUFFER(msgbuf), 8);
595		WRITE(BUFFER(msgbuf), 8);
596	}
597	/*
598	 * at EOF or last block -- in either case, the last byte contains
599	 * the character representation of the number of bytes in it
600	 */
601	bn++;
602	MEMZERO(&CHAR(msgbuf, n), 8 - n);
603	CHAR(msgbuf, 7) = n;
604	for (n = 0; n < 8; n++)
605		CHAR(msgbuf, n) ^= CHAR(ivec, n);
606	DES_XFORM(UBUFFER(msgbuf));
607	WRITE(BUFFER(msgbuf), 8);
608
609}
610
611/*
612 * This decrypts using the Cipher Block Chaining mode of DES
613 */
614cbcdec()
615{
616	register int n;		/* number of bytes actually read */
617	Desbuf msgbuf;		/* I/O buffer */
618	Desbuf ibuf;		/* temp buffer for initialization vector */
619	register int c;		/* used to test for EOF */
620	register int bn;	/* block number */
621
622	for (bn = 0; (n = READ(BUFFER(msgbuf), 8)) == 8; bn++) {
623		/*
624		 * do the transformation
625		 */
626		MEMCPY(BUFFER(ibuf), BUFFER(msgbuf), 8);
627		DES_XFORM(UBUFFER(msgbuf));
628		for (c = 0; c < 8; c++)
629			UCHAR(msgbuf, c) ^= UCHAR(ivec, c);
630		MEMCPY(BUFFER(ivec), BUFFER(ibuf), 8);
631		/*
632		 * if the last one, handle it specially
633		 */
634		if ((c = getchar()) == EOF) {
635			n = CHAR(msgbuf, 7);
636			if (n < 0 || n > 7)
637				err(bn, "decryption failed (block corrupted)");
638		}
639		else
640			(void)ungetc(c, stdin);
641		WRITE(BUFFER(msgbuf), n);
642	}
643	if (n > 0)
644		err(bn, "decryption failed (incomplete block)");
645}
646
647/*
648 * This authenticates using the Cipher Block Chaining mode of DES
649 */
650cbcauth()
651{
652	register int n, j;		/* number of bytes actually read */
653	Desbuf msgbuf;		/* I/O buffer */
654	Desbuf encbuf;		/* encryption buffer */
655
656	/*
657	 * do the transformation
658	 * note we DISCARD the encrypted block;
659	 * we only care about the last one
660	 */
661	while ((n = READ(BUFFER(msgbuf), 8)) == 8) {
662		for (n = 0; n < 8; n++)
663			CHAR(encbuf, n) = CHAR(msgbuf, n) ^ CHAR(ivec, n);
664		DES_XFORM(UBUFFER(encbuf));
665		MEMCPY(BUFFER(ivec), BUFFER(encbuf), 8);
666	}
667	/*
668	 * now compute the last one, right padding with '\0' if need be
669	 */
670	if (n > 0) {
671		MEMZERO(&CHAR(msgbuf, n), 8 - n);
672		for (n = 0; n < 8; n++)
673			CHAR(encbuf, n) = CHAR(msgbuf, n) ^ CHAR(ivec, n);
674		DES_XFORM(UBUFFER(encbuf));
675	}
676	/*
677	 * drop the bits
678	 * we write chars until fewer than 7 bits,
679	 * and then pad the last one with 0 bits
680	 */
681	for (n = 0; macbits > 7; n++, macbits -= 8)
682		(void)putchar(CHAR(encbuf, n));
683	if (macbits > 0) {
684		CHAR(msgbuf, 0) = 0x00;
685		for (j = 0; j < macbits; j++)
686			CHAR(msgbuf, 0) |= (CHAR(encbuf, n)&bits[j]);
687		(void)putchar(CHAR(msgbuf, 0));
688	}
689}
690
691/*
692 * This encrypts using the Cipher FeedBack mode of DES
693 */
694cfbenc()
695{
696	register int n;		/* number of bytes actually read */
697	register int nbytes;	/* number of bytes to read */
698	register int bn;	/* block number */
699	char ibuf[8];		/* input buffer */
700	Desbuf msgbuf;		/* encryption buffer */
701
702	/*
703	 * do things in bytes, not bits
704	 */
705	nbytes = fbbits / 8;
706	/*
707	 * do the transformation
708	 */
709	for (bn = 1; (n = READ(ibuf, nbytes)) == nbytes; bn++) {
710		MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
711		DES_XFORM(UBUFFER(msgbuf));
712		for (n = 0; n < 8 - nbytes; n++)
713			UCHAR(ivec, n) = UCHAR(ivec, n+nbytes);
714		for (n = 0; n < nbytes; n++)
715			UCHAR(ivec, 8-nbytes+n) = ibuf[n] ^ UCHAR(msgbuf, n);
716		WRITE(&CHAR(ivec, 8-nbytes), nbytes);
717	}
718	/*
719	 * at EOF or last block -- in either case, the last byte contains
720	 * the character representation of the number of bytes in it
721	 */
722	bn++;
723	MEMZERO(&ibuf[n], nbytes - n);
724	ibuf[nbytes - 1] = n;
725	MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
726	DES_XFORM(UBUFFER(msgbuf));
727	for (n = 0; n < nbytes; n++)
728		ibuf[n] ^= UCHAR(msgbuf, n);
729	WRITE(ibuf, nbytes);
730}
731
732/*
733 * This decrypts using the Cipher Block Chaining mode of DES
734 */
735cfbdec()
736{
737	register int n;		/* number of bytes actually read */
738	register int c;		/* used to test for EOF */
739	register int nbytes;	/* number of bytes to read */
740	register int bn;	/* block number */
741	char ibuf[8];		/* input buffer */
742	char obuf[8];		/* output buffer */
743	Desbuf msgbuf;		/* encryption buffer */
744
745	/*
746	 * do things in bytes, not bits
747	 */
748	nbytes = fbbits / 8;
749	/*
750	 * do the transformation
751	 */
752	for (bn = 1; (n = READ(ibuf, nbytes)) == nbytes; bn++) {
753		MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
754		DES_XFORM(UBUFFER(msgbuf));
755		for (c = 0; c < 8 - nbytes; c++)
756			CHAR(ivec, c) = CHAR(ivec, c+nbytes);
757		for (c = 0; c < nbytes; c++) {
758			CHAR(ivec, 8-nbytes+c) = ibuf[c];
759			obuf[c] = ibuf[c] ^ UCHAR(msgbuf, c);
760		}
761		/*
762		 * if the last one, handle it specially
763		 */
764		if ((c = getchar()) == EOF) {
765			n = obuf[nbytes-1];
766			if (n < 0 || n > nbytes-1)
767				err(bn, "decryption failed (block corrupted)");
768		}
769		else
770			(void)ungetc(c, stdin);
771		WRITE(obuf, n);
772	}
773	if (n > 0)
774		err(bn, "decryption failed (incomplete block)");
775}
776
777/*
778 * This encrypts using the alternative Cipher FeedBack mode of DES
779 */
780cfbaenc()
781{
782	register int n;		/* number of bytes actually read */
783	register int nbytes;	/* number of bytes to read */
784	register int bn;	/* block number */
785	char ibuf[8];		/* input buffer */
786	char obuf[8];		/* output buffer */
787	Desbuf msgbuf;		/* encryption buffer */
788
789	/*
790	 * do things in bytes, not bits
791	 */
792	nbytes = fbbits / 7;
793	/*
794	 * do the transformation
795	 */
796	for (bn = 1; (n = READ(ibuf, nbytes)) == nbytes; bn++) {
797		MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
798		DES_XFORM(UBUFFER(msgbuf));
799		for (n = 0; n < 8 - nbytes; n++)
800			UCHAR(ivec, n) = UCHAR(ivec, n+nbytes);
801		for (n = 0; n < nbytes; n++)
802			UCHAR(ivec, 8-nbytes+n) = (ibuf[n] ^ UCHAR(msgbuf, n))
803							|0200;
804		for (n = 0; n < nbytes; n++)
805			obuf[n] = CHAR(ivec, 8-nbytes+n)&0177;
806		WRITE(obuf, nbytes);
807	}
808	/*
809	 * at EOF or last block -- in either case, the last byte contains
810	 * the character representation of the number of bytes in it
811	 */
812	bn++;
813	MEMZERO(&ibuf[n], nbytes - n);
814	ibuf[nbytes - 1] = ('0' + n)|0200;
815	MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
816	DES_XFORM(UBUFFER(msgbuf));
817	for (n = 0; n < nbytes; n++)
818		ibuf[n] ^= UCHAR(msgbuf, n);
819	WRITE(ibuf, nbytes);
820}
821
822/*
823 * This decrypts using the alternative Cipher Block Chaining mode of DES
824 */
825cfbadec()
826{
827	register int n;		/* number of bytes actually read */
828	register int c;		/* used to test for EOF */
829	register int nbytes;	/* number of bytes to read */
830	register int bn;	/* block number */
831	char ibuf[8];		/* input buffer */
832	char obuf[8];		/* output buffer */
833	Desbuf msgbuf;		/* encryption buffer */
834
835	/*
836	 * do things in bytes, not bits
837	 */
838	nbytes = fbbits / 7;
839	/*
840	 * do the transformation
841	 */
842	for (bn = 1; (n = READ(ibuf, nbytes)) == nbytes; bn++) {
843		MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
844		DES_XFORM(UBUFFER(msgbuf));
845		for (c = 0; c < 8 - nbytes; c++)
846			CHAR(ivec, c) = CHAR(ivec, c+nbytes);
847		for (c = 0; c < nbytes; c++) {
848			CHAR(ivec, 8-nbytes+c) = ibuf[c]|0200;
849			obuf[c] = (ibuf[c] ^ UCHAR(msgbuf, c))&0177;
850		}
851		/*
852		 * if the last one, handle it specially
853		 */
854		if ((c = getchar()) == EOF) {
855			if ((n = (obuf[nbytes-1] - '0')) < 0
856						|| n > nbytes-1)
857				err(bn, "decryption failed (block corrupted)");
858		}
859		else
860			(void)ungetc(c, stdin);
861		WRITE(obuf, n);
862	}
863	if (n > 0)
864		err(bn, "decryption failed (incomplete block)");
865}
866
867
868/*
869 * This encrypts using the Output FeedBack mode of DES
870 */
871ofbenc()
872{
873	register int n;		/* number of bytes actually read */
874	register int c;		/* used to test for EOF */
875	register int nbytes;	/* number of bytes to read */
876	register int bn;	/* block number */
877	char ibuf[8];		/* input buffer */
878	char obuf[8];		/* output buffer */
879	Desbuf msgbuf;		/* encryption buffer */
880
881	/*
882	 * do things in bytes, not bits
883	 */
884	nbytes = fbbits / 8;
885	/*
886	 * do the transformation
887	 */
888	for (bn = 1; (n = READ(ibuf, nbytes)) == nbytes; bn++) {
889		MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
890		DES_XFORM(UBUFFER(msgbuf));
891		for (n = 0; n < 8 - nbytes; n++)
892			UCHAR(ivec, n) = UCHAR(ivec, n+nbytes);
893		for (n = 0; n < nbytes; n++) {
894			UCHAR(ivec, 8-nbytes+n) = UCHAR(msgbuf, n);
895			obuf[n] = ibuf[n] ^ UCHAR(msgbuf, n);
896		}
897		WRITE(obuf, nbytes);
898	}
899	/*
900	 * at EOF or last block -- in either case, the last byte contains
901	 * the character representation of the number of bytes in it
902	 */
903	bn++;
904	MEMZERO(&ibuf[n], nbytes - n);
905	ibuf[nbytes - 1] = n;
906	MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
907	DES_XFORM(UBUFFER(msgbuf));
908	for (c = 0; c < nbytes; c++)
909		ibuf[c] ^= UCHAR(msgbuf, c);
910	WRITE(ibuf, nbytes);
911}
912
913/*
914 * This decrypts using the Output Block Chaining mode of DES
915 */
916ofbdec()
917{
918	register int n;		/* number of bytes actually read */
919	register int c;		/* used to test for EOF */
920	register int nbytes;	/* number of bytes to read */
921	register int bn;	/* block number */
922	char ibuf[8];		/* input buffer */
923	char obuf[8];		/* output buffer */
924	Desbuf msgbuf;		/* encryption buffer */
925
926	/*
927	 * do things in bytes, not bits
928	 */
929	nbytes = fbbits / 8;
930	/*
931	 * do the transformation
932	 */
933	for (bn = 1; (n = READ(ibuf, nbytes)) == nbytes; bn++) {
934		MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
935		DES_XFORM(UBUFFER(msgbuf));
936		for (c = 0; c < 8 - nbytes; c++)
937			CHAR(ivec, c) = CHAR(ivec, c+nbytes);
938		for (c = 0; c < nbytes; c++) {
939			CHAR(ivec, 8-nbytes+c) = UCHAR(msgbuf, c);
940			obuf[c] = ibuf[c] ^ UCHAR(msgbuf, c);
941		}
942		/*
943		 * if the last one, handle it specially
944		 */
945		if ((c = getchar()) == EOF) {
946			n = obuf[nbytes-1];
947			if (n < 0 || n > nbytes-1)
948				err(bn, "decryption failed (block corrupted)");
949		}
950		else
951			(void)ungetc(c, stdin);
952		/*
953		 * dump it
954		 */
955		WRITE(obuf, n);
956	}
957	if (n > 0)
958		err(bn, "decryption failed (incomplete block)");
959}
960
961/*
962 * This authenticates using the Cipher FeedBack mode of DES
963 */
964cfbauth()
965{
966	register int n, j;	/* number of bytes actually read */
967	register int nbytes;	/* number of bytes to read */
968	char ibuf[8];		/* input buffer */
969	Desbuf msgbuf;		/* encryption buffer */
970
971	/*
972	 * do things in bytes, not bits
973	 */
974	nbytes = fbbits / 8;
975	/*
976	 * do the transformation
977	 */
978	while ((n = READ(ibuf, nbytes)) == nbytes) {
979		MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
980		DES_XFORM(UBUFFER(msgbuf));
981		for (n = 0; n < 8 - nbytes; n++)
982			UCHAR(ivec, n) = UCHAR(ivec, n+nbytes);
983		for (n = 0; n < nbytes; n++)
984			UCHAR(ivec, 8-nbytes+n) = ibuf[n] ^ UCHAR(msgbuf, n);
985	}
986	/*
987	 * at EOF or last block -- in either case, the last byte contains
988	 * the character representation of the number of bytes in it
989	 */
990	MEMZERO(&ibuf[n], nbytes - n);
991	ibuf[nbytes - 1] = '0' + n;
992	MEMCPY(BUFFER(msgbuf), BUFFER(ivec), 8);
993	DES_XFORM(UBUFFER(msgbuf));
994	for (n = 0; n < nbytes; n++)
995		ibuf[n] ^= UCHAR(msgbuf, n);
996	/*
997	 * drop the bits
998	 * we write chars until fewer than 7 bits,
999	 * and then pad the last one with 0 bits
1000	 */
1001	for (n = 0; macbits > 7; n++, macbits -= 8)
1002		(void)putchar(CHAR(msgbuf, n));
1003	if (macbits > 0) {
1004		CHAR(msgbuf, 0) = 0x00;
1005		for (j = 0; j < macbits; j++)
1006			CHAR(msgbuf, 0) |= (CHAR(msgbuf, n)&bits[j]);
1007		(void)putchar(CHAR(msgbuf, 0));
1008	}
1009}
1010
1011#ifndef FASTWAY
1012/*
1013 * change from 8 bits/Uchar to 1 bit/Uchar
1014 */
1015expand(from, to)
1016	Desbuf from;			/* 8bit/unsigned char string */
1017	char *to;			/* 1bit/char string */
1018{
1019	register int i, j;		/* counters in for loop */
1020
1021	for (i = 0; i < 8; i++)
1022		for (j = 0; j < 8; j++)
1023			*to++ = (CHAR(from, i)>>(7-j))&01;
1024}
1025
1026/*
1027 * change from 1 bit/char to 8 bits/Uchar
1028 */
1029compress(from, to)
1030	char *from;			/* 1bit/char string */
1031	Desbuf to;			/* 8bit/unsigned char string */
1032{
1033	register int i, j;		/* counters in for loop */
1034
1035	for (i = 0; i < 8; i++) {
1036	 	CHAR(to, i) = 0;
1037		for (j = 0; j < 8; j++)
1038			CHAR(to, i) = ((*from++)<<(7-j))|CHAR(to, i);
1039	}
1040}
1041#endif
1042
1043/*
1044 * message about usage
1045 */
1046usage()
1047{
1048	(void)fprintf(stderr, "%s\n",
1049"usage: bdes [-abdp] [-F bit] [-f bit] [-k key] [-m bit] [-o bit] [-v vector]");
1050	exit(1);
1051}
1052