1/*
2 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23/*
24 * Copyright (c) 1989, 1993
25 *	The Regents of the University of California.  All rights reserved.
26 *
27 * This code is derived from software contributed to Berkeley by
28 * Tom Truscott.
29 *
30 * Redistribution and use in source and binary forms, with or without
31 * modification, are permitted provided that the following conditions
32 * are met:
33 * 1. Redistributions of source code must retain the above copyright
34 *    notice, this list of conditions and the following disclaimer.
35 * 2. Redistributions in binary form must reproduce the above copyright
36 *    notice, this list of conditions and the following disclaimer in the
37 *    documentation and/or other materials provided with the distribution.
38 * 3. All advertising materials mentioning features or use of this software
39 *    must display the following acknowledgement:
40 *	This product includes software developed by the University of
41 *	California, Berkeley and its contributors.
42 * 4. Neither the name of the University nor the names of its contributors
43 *    may be used to endorse or promote products derived from this software
44 *    without specific prior written permission.
45 *
46 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
47 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
50 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56 * SUCH DAMAGE.
57 */
58
59
60#include <sys/cdefs.h>
61#include <unistd.h>
62#include <limits.h>
63#include <sys/types.h>
64#include <pwd.h>
65#include <stdlib.h>
66
67/*
68 * UNIX password, and DES, encryption.
69 * By Tom Truscott, trt@rti.rti.org,
70 * from algorithms by Robert W. Baldwin and James Gillogly.
71 *
72 * References:
73 * "Mathematical Cryptology for Computer Scientists and Mathematicians,"
74 * by Wayne Patterson, 1987, ISBN 0-8476-7438-X.
75 *
76 * "Password Security: A Case History," R. Morris and Ken Thompson,
77 * Communications of the ACM, vol. 22, pp. 594-597, Nov. 1979.
78 *
79 * "DES will be Totally Insecure within Ten Years," M.E. Hellman,
80 * IEEE Spectrum, vol. 16, pp. 32-39, July 1979.
81 */
82
83/* =====  Configuration ==================== */
84
85/*
86 * define "MUST_ALIGN" if your compiler cannot load/store
87 * long integers at arbitrary (e.g. odd) memory locations.
88 * (Either that or never pass unaligned addresses to __crypt_des_cipher!)
89 */
90#if !defined(vax)
91#define	MUST_ALIGN
92#endif
93
94#ifdef CHAR_BITS
95#if CHAR_BITS != 8
96	#error C_block structure assumes 8 bit characters
97#endif
98#endif
99
100/*
101 * define "LONG_IS_32_BITS" only if sizeof(long)==4.
102 * This avoids use of bit fields (your compiler may be sloppy with them).
103 */
104#if !defined(cray) && (LONG_BIT == 32)
105#define	LONG_IS_32_BITS
106#endif
107
108/*
109 * define "B64" to be the declaration for a 64 bit integer.
110 * XXX this feature is currently unused, see "endian" comment below.
111 */
112#if defined(cray)
113#define	B64	long
114#endif
115#if defined(convex)
116#define	B64	long long
117#endif
118
119/*
120 * define "LARGEDATA" to get faster permutations, by using about 72 kilobytes
121 * of lookup tables.  This speeds up __crypt_des_setkey() and __crypt_des_cipher(), but has
122 * little effect on crypt().
123 */
124#if defined(notdef)
125#define	LARGEDATA
126#endif
127
128/* compile with "-DSTATIC=int" when profiling */
129#ifndef STATIC
130#define	STATIC	static
131#endif
132#ifndef BUILDING_VARIANT
133STATIC void init_des(), init_perm(), permute();
134#ifdef DEBUG
135#include <stdio.h>
136STATIC void prtab();
137#endif
138#endif /* BUILDING_VARIANT */
139__private_extern__ int __crypt_des_cipher(), __crypt_des_setkey();
140
141/* ==================================== */
142
143/*
144 * Cipher-block representation (Bob Baldwin):
145 *
146 * DES operates on groups of 64 bits, numbered 1..64 (sigh).  One
147 * representation is to store one bit per byte in an array of bytes.  Bit N of
148 * the NBS spec is stored as the LSB of the Nth byte (index N-1) in the array.
149 * Another representation stores the 64 bits in 8 bytes, with bits 1..8 in the
150 * first byte, 9..16 in the second, and so on.  The DES spec apparently has
151 * bit 1 in the MSB of the first byte, but that is particularly noxious so we
152 * bit-reverse each byte so that bit 1 is the LSB of the first byte, bit 8 is
153 * the MSB of the first byte.  Specifically, the 64-bit input data and key are
154 * converted to LSB format, and the output 64-bit block is converted back into
155 * MSB format.
156 *
157 * DES operates internally on groups of 32 bits which are expanded to 48 bits
158 * by permutation E and shrunk back to 32 bits by the S boxes.  To speed up
159 * the computation, the expansion is applied only once, the expanded
160 * representation is maintained during the encryption, and a compression
161 * permutation is applied only at the end.  To speed up the S-box lookups,
162 * the 48 bits are maintained as eight 6 bit groups, one per byte, which
163 * directly feed the eight S-boxes.  Within each byte, the 6 bits are the
164 * most significant ones.  The low two bits of each byte are zero.  (Thus,
165 * bit 1 of the 48 bit E expansion is stored as the "4"-valued bit of the
166 * first byte in the eight byte representation, bit 2 of the 48 bit value is
167 * the "8"-valued bit, and so on.)  In fact, a combined "SPE"-box lookup is
168 * used, in which the output is the 64 bit result of an S-box lookup which
169 * has been permuted by P and expanded by E, and is ready for use in the next
170 * iteration.  Two 32-bit wide tables, SPE[0] and SPE[1], are used for this
171 * lookup.  Since each byte in the 48 bit path is a multiple of four, indexed
172 * lookup of SPE[0] and SPE[1] is simple and fast.  The key schedule and
173 * "salt" are also converted to this 8*(6+2) format.  The SPE table size is
174 * 8*64*8 = 4K bytes.
175 *
176 * To speed up bit-parallel operations (such as XOR), the 8 byte
177 * representation is "union"ed with 32 bit values "i0" and "i1", and, on
178 * machines which support it, a 64 bit value "b64".  This data structure,
179 * "C_block", has two problems.  First, alignment restrictions must be
180 * honored.  Second, the byte-order (e.g. little-endian or big-endian) of
181 * the architecture becomes visible.
182 *
183 * The byte-order problem is unfortunate, since on the one hand it is good
184 * to have a machine-independent C_block representation (bits 1..8 in the
185 * first byte, etc.), and on the other hand it is good for the LSB of the
186 * first byte to be the LSB of i0.  We cannot have both these things, so we
187 * currently use the "little-endian" representation and avoid any multi-byte
188 * operations that depend on byte order.  This largely precludes use of the
189 * 64-bit datatype since the relative order of i0 and i1 are unknown.  It
190 * also inhibits grouping the SPE table to look up 12 bits at a time.  (The
191 * 12 bits can be stored in a 16-bit field with 3 low-order zeroes and 1
192 * high-order zero, providing fast indexing into a 64-bit wide SPE.)  On the
193 * other hand, 64-bit datatypes are currently rare, and a 12-bit SPE lookup
194 * requires a 128 kilobyte table, so perhaps this is not a big loss.
195 *
196 * Permutation representation (Jim Gillogly):
197 *
198 * A transformation is defined by its effect on each of the 8 bytes of the
199 * 64-bit input.  For each byte we give a 64-bit output that has the bits in
200 * the input distributed appropriately.  The transformation is then the OR
201 * of the 8 sets of 64-bits.  This uses 8*256*8 = 16K bytes of storage for
202 * each transformation.  Unless LARGEDATA is defined, however, a more compact
203 * table is used which looks up 16 4-bit "chunks" rather than 8 8-bit chunks.
204 * The smaller table uses 16*16*8 = 2K bytes for each transformation.  This
205 * is slower but tolerable, particularly for password encryption in which
206 * the SPE transformation is iterated many times.  The small tables total 9K
207 * bytes, the large tables total 72K bytes.
208 *
209 * The transformations used are:
210 * IE3264: MSB->LSB conversion, initial permutation, and expansion.
211 *	This is done by collecting the 32 even-numbered bits and applying
212 *	a 32->64 bit transformation, and then collecting the 32 odd-numbered
213 *	bits and applying the same transformation.  Since there are only
214 *	32 input bits, the IE3264 transformation table is half the size of
215 *	the usual table.
216 * CF6464: Compression, final permutation, and LSB->MSB conversion.
217 *	This is done by two trivial 48->32 bit compressions to obtain
218 *	a 64-bit block (the bit numbering is given in the "CIFP" table)
219 *	followed by a 64->64 bit "cleanup" transformation.  (It would
220 *	be possible to group the bits in the 64-bit block so that 2
221 *	identical 32->32 bit transformations could be used instead,
222 *	saving a factor of 4 in space and possibly 2 in time, but
223 *	byte-ordering and other complications rear their ugly head.
224 *	Similar opportunities/problems arise in the key schedule
225 *	transforms.)
226 * PC1ROT: MSB->LSB, PC1 permutation, rotate, and PC2 permutation.
227 *	This admittedly baroque 64->64 bit transformation is used to
228 *	produce the first code (in 8*(6+2) format) of the key schedule.
229 * PC2ROT[0]: Inverse PC2 permutation, rotate, and PC2 permutation.
230 *	It would be possible to define 15 more transformations, each
231 *	with a different rotation, to generate the entire key schedule.
232 *	To save space, however, we instead permute each code into the
233 *	next by using a transformation that "undoes" the PC2 permutation,
234 *	rotates the code, and then applies PC2.  Unfortunately, PC2
235 *	transforms 56 bits into 48 bits, dropping 8 bits, so PC2 is not
236 *	invertible.  We get around that problem by using a modified PC2
237 *	which retains the 8 otherwise-lost bits in the unused low-order
238 *	bits of each byte.  The low-order bits are cleared when the
239 *	codes are stored into the key schedule.
240 * PC2ROT[1]: Same as PC2ROT[0], but with two rotations.
241 *	This is faster than applying PC2ROT[0] twice,
242 *
243 * The Bell Labs "salt" (Bob Baldwin):
244 *
245 * The salting is a simple permutation applied to the 48-bit result of E.
246 * Specifically, if bit i (1 <= i <= 24) of the salt is set then bits i and
247 * i+24 of the result are swapped.  The salt is thus a 24 bit number, with
248 * 16777216 possible values.  (The original salt was 12 bits and could not
249 * swap bits 13..24 with 36..48.)
250 *
251 * It is possible, but ugly, to warp the SPE table to account for the salt
252 * permutation.  Fortunately, the conditional bit swapping requires only
253 * about four machine instructions and can be done on-the-fly with about an
254 * 8% performance penalty.
255 */
256
257typedef union {
258	unsigned char b[8];
259	struct {
260#if defined(LONG_IS_32_BITS)
261		/* long is often faster than a 32-bit bit field */
262		long	i0;
263		long	i1;
264#else
265		long	i0: 32;
266		long	i1: 32;
267#endif
268	} b32;
269#if defined(B64)
270	B64	b64;
271#endif
272} C_block;
273
274/*
275 * Convert twenty-four-bit long in host-order
276 * to six bits (and 2 low-order zeroes) per char little-endian format.
277 */
278#define	TO_SIX_BIT(rslt, src) {				\
279		C_block cvt;				\
280		cvt.b[0] = src; src >>= 6;		\
281		cvt.b[1] = src; src >>= 6;		\
282		cvt.b[2] = src; src >>= 6;		\
283		cvt.b[3] = src;				\
284		rslt = (cvt.b32.i0 & 0x3f3f3f3fL) << 2;	\
285	}
286
287/*
288 * These macros may someday permit efficient use of 64-bit integers.
289 */
290#define	ZERO(d,d0,d1)			d0 = 0, d1 = 0
291#define	LOAD(d,d0,d1,bl)		d0 = (bl).b32.i0, d1 = (bl).b32.i1
292#define	LOADREG(d,d0,d1,s,s0,s1)	d0 = s0, d1 = s1
293#define	OR(d,d0,d1,bl)			d0 |= (bl).b32.i0, d1 |= (bl).b32.i1
294#define	STORE(s,s0,s1,bl)		(bl).b32.i0 = s0, (bl).b32.i1 = s1
295#define	DCL_BLOCK(d,d0,d1)		long d0, d1
296
297#if defined(LARGEDATA)
298	/* Waste memory like crazy.  Also, do permutations in line */
299#define	LGCHUNKBITS	3
300#define	CHUNKBITS	(1<<LGCHUNKBITS)
301#define	PERM6464(d,d0,d1,cpp,p)				\
302	LOAD(d,d0,d1,(p)[(0<<CHUNKBITS)+(cpp)[0]]);		\
303	OR (d,d0,d1,(p)[(1<<CHUNKBITS)+(cpp)[1]]);		\
304	OR (d,d0,d1,(p)[(2<<CHUNKBITS)+(cpp)[2]]);		\
305	OR (d,d0,d1,(p)[(3<<CHUNKBITS)+(cpp)[3]]);		\
306	OR (d,d0,d1,(p)[(4<<CHUNKBITS)+(cpp)[4]]);		\
307	OR (d,d0,d1,(p)[(5<<CHUNKBITS)+(cpp)[5]]);		\
308	OR (d,d0,d1,(p)[(6<<CHUNKBITS)+(cpp)[6]]);		\
309	OR (d,d0,d1,(p)[(7<<CHUNKBITS)+(cpp)[7]]);
310#define	PERM3264(d,d0,d1,cpp,p)				\
311	LOAD(d,d0,d1,(p)[(0<<CHUNKBITS)+(cpp)[0]]);		\
312	OR (d,d0,d1,(p)[(1<<CHUNKBITS)+(cpp)[1]]);		\
313	OR (d,d0,d1,(p)[(2<<CHUNKBITS)+(cpp)[2]]);		\
314	OR (d,d0,d1,(p)[(3<<CHUNKBITS)+(cpp)[3]]);
315#else
316	/* "small data" */
317#define	LGCHUNKBITS	2
318#define	CHUNKBITS	(1<<LGCHUNKBITS)
319#define	PERM6464(d,d0,d1,cpp,p)				\
320	{ C_block tblk; permute(cpp,&tblk,p,8); LOAD (d,d0,d1,tblk); }
321#define	PERM3264(d,d0,d1,cpp,p)				\
322	{ C_block tblk; permute(cpp,&tblk,p,4); LOAD (d,d0,d1,tblk); }
323
324#ifndef BUILDING_VARIANT
325STATIC void permute(cp, out, p, chars_in)
326	unsigned char *cp;
327	C_block *out;
328	register C_block *p;
329	int chars_in;
330{
331	register DCL_BLOCK(D,D0,D1);
332	register C_block *tp;
333	register int t;
334
335	ZERO(D,D0,D1);
336	do {
337		t = *cp++;
338		tp = &p[t&0xf]; OR(D,D0,D1,*tp); p += (1<<CHUNKBITS);
339		tp = &p[t>>4];  OR(D,D0,D1,*tp); p += (1<<CHUNKBITS);
340	} while (--chars_in > 0);
341	STORE(D,D0,D1,*out);
342}
343#endif /* BUILDING_VARIANT */
344#endif /* LARGEDATA */
345
346#ifndef BUILDING_VARIANT
347__private_extern__ int __crypt_des_setkey_called = 0;
348#else /* BUILDING_VARIANT */
349__private_extern__ int __crypt_des_setkey_called;
350#endif /* BUILDING_VARIANT */
351
352/* =====  (mostly) Standard DES Tables ==================== */
353
354#ifndef BUILDING_VARIANT
355static const unsigned char IP[] = {		/* initial permutation */
356	58, 50, 42, 34, 26, 18, 10,  2,
357	60, 52, 44, 36, 28, 20, 12,  4,
358	62, 54, 46, 38, 30, 22, 14,  6,
359	64, 56, 48, 40, 32, 24, 16,  8,
360	57, 49, 41, 33, 25, 17,  9,  1,
361	59, 51, 43, 35, 27, 19, 11,  3,
362	61, 53, 45, 37, 29, 21, 13,  5,
363	63, 55, 47, 39, 31, 23, 15,  7,
364};
365
366/* The final permutation is the inverse of IP - no table is necessary */
367
368static const unsigned char ExpandTr[] = {	/* expansion operation */
369	32,  1,  2,  3,  4,  5,
370	 4,  5,  6,  7,  8,  9,
371	 8,  9, 10, 11, 12, 13,
372	12, 13, 14, 15, 16, 17,
373	16, 17, 18, 19, 20, 21,
374	20, 21, 22, 23, 24, 25,
375	24, 25, 26, 27, 28, 29,
376	28, 29, 30, 31, 32,  1,
377};
378
379static const unsigned char PC1[] = {		/* permuted choice table 1 */
380	57, 49, 41, 33, 25, 17,  9,
381	 1, 58, 50, 42, 34, 26, 18,
382	10,  2, 59, 51, 43, 35, 27,
383	19, 11,  3, 60, 52, 44, 36,
384
385	63, 55, 47, 39, 31, 23, 15,
386	 7, 62, 54, 46, 38, 30, 22,
387	14,  6, 61, 53, 45, 37, 29,
388	21, 13,  5, 28, 20, 12,  4,
389};
390
391static const unsigned char Rotates[] = {	/* PC1 rotation schedule */
392	1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1,
393};
394
395/* note: each "row" of PC2 is left-padded with bits that make it invertible */
396static const unsigned char PC2[] = {		/* permuted choice table 2 */
397	 9, 18,    14, 17, 11, 24,  1,  5,
398	22, 25,     3, 28, 15,  6, 21, 10,
399	35, 38,    23, 19, 12,  4, 26,  8,
400	43, 54,    16,  7, 27, 20, 13,  2,
401
402	 0,  0,    41, 52, 31, 37, 47, 55,
403	 0,  0,    30, 40, 51, 45, 33, 48,
404	 0,  0,    44, 49, 39, 56, 34, 53,
405	 0,  0,    46, 42, 50, 36, 29, 32,
406};
407
408static const unsigned char S[8][64] = {	/* 48->32 bit substitution tables */
409	{				/* S[1]			*/
410	14,  4, 13,  1,  2, 15, 11,  8,  3, 10,  6, 12,  5,  9,  0,  7,
411	 0, 15,  7,  4, 14,  2, 13,  1, 10,  6, 12, 11,  9,  5,  3,  8,
412	 4,  1, 14,  8, 13,  6,  2, 11, 15, 12,  9,  7,  3, 10,  5,  0,
413	15, 12,  8,  2,  4,  9,  1,  7,  5, 11,  3, 14, 10,  0,  6, 13,
414	},
415	{				/* S[2]			*/
416	15,  1,  8, 14,  6, 11,  3,  4,  9,  7,  2, 13, 12,  0,  5, 10,
417	 3, 13,  4,  7, 15,  2,  8, 14, 12,  0,  1, 10,  6,  9, 11,  5,
418	 0, 14,  7, 11, 10,  4, 13,  1,  5,  8, 12,  6,  9,  3,  2, 15,
419	13,  8, 10,  1,  3, 15,  4,  2, 11,  6,  7, 12,  0,  5, 14,  9,
420	},
421	{				/* S[3]			*/
422	10,  0,  9, 14,  6,  3, 15,  5,  1, 13, 12,  7, 11,  4,  2,  8,
423	13,  7,  0,  9,  3,  4,  6, 10,  2,  8,  5, 14, 12, 11, 15,  1,
424	13,  6,  4,  9,  8, 15,  3,  0, 11,  1,  2, 12,  5, 10, 14,  7,
425	 1, 10, 13,  0,  6,  9,  8,  7,  4, 15, 14,  3, 11,  5,  2, 12,
426	},
427	{				/* S[4]			*/
428	 7, 13, 14,  3,  0,  6,  9, 10,  1,  2,  8,  5, 11, 12,  4, 15,
429	13,  8, 11,  5,  6, 15,  0,  3,  4,  7,  2, 12,  1, 10, 14,  9,
430	10,  6,  9,  0, 12, 11,  7, 13, 15,  1,  3, 14,  5,  2,  8,  4,
431	 3, 15,  0,  6, 10,  1, 13,  8,  9,  4,  5, 11, 12,  7,  2, 14,
432	},
433	{				/* S[5]			*/
434	 2, 12,  4,  1,  7, 10, 11,  6,  8,  5,  3, 15, 13,  0, 14,  9,
435	14, 11,  2, 12,  4,  7, 13,  1,  5,  0, 15, 10,  3,  9,  8,  6,
436	 4,  2,  1, 11, 10, 13,  7,  8, 15,  9, 12,  5,  6,  3,  0, 14,
437	11,  8, 12,  7,  1, 14,  2, 13,  6, 15,  0,  9, 10,  4,  5,  3,
438	},
439	{				/* S[6]			*/
440	12,  1, 10, 15,  9,  2,  6,  8,  0, 13,  3,  4, 14,  7,  5, 11,
441	10, 15,  4,  2,  7, 12,  9,  5,  6,  1, 13, 14,  0, 11,  3,  8,
442	 9, 14, 15,  5,  2,  8, 12,  3,  7,  0,  4, 10,  1, 13, 11,  6,
443	 4,  3,  2, 12,  9,  5, 15, 10, 11, 14,  1,  7,  6,  0,  8, 13,
444	},
445	{				/* S[7]			*/
446	 4, 11,  2, 14, 15,  0,  8, 13,  3, 12,  9,  7,  5, 10,  6,  1,
447	13,  0, 11,  7,  4,  9,  1, 10, 14,  3,  5, 12,  2, 15,  8,  6,
448	 1,  4, 11, 13, 12,  3,  7, 14, 10, 15,  6,  8,  0,  5,  9,  2,
449	 6, 11, 13,  8,  1,  4, 10,  7,  9,  5,  0, 15, 14,  2,  3, 12,
450	},
451	{				/* S[8]			*/
452	13,  2,  8,  4,  6, 15, 11,  1, 10,  9,  3, 14,  5,  0, 12,  7,
453	 1, 15, 13,  8, 10,  3,  7,  4, 12,  5,  6, 11,  0, 14,  9,  2,
454	 7, 11,  4,  1,  9, 12, 14,  2,  0,  6, 10, 13, 15,  3,  5,  8,
455	 2,  1, 14,  7,  4, 10,  8, 13, 15, 12,  9,  0,  3,  5,  6, 11,
456	},
457};
458
459static const unsigned char P32Tr[] = {	/* 32-bit permutation function */
460	16,  7, 20, 21,
461	29, 12, 28, 17,
462	 1, 15, 23, 26,
463	 5, 18, 31, 10,
464	 2,  8, 24, 14,
465	32, 27,  3,  9,
466	19, 13, 30,  6,
467	22, 11,  4, 25,
468};
469
470static const unsigned char CIFP[] = {		/* compressed/interleaved permutation */
471	 1,  2,  3,  4,   17, 18, 19, 20,
472	 5,  6,  7,  8,   21, 22, 23, 24,
473	 9, 10, 11, 12,   25, 26, 27, 28,
474	13, 14, 15, 16,   29, 30, 31, 32,
475
476	33, 34, 35, 36,   49, 50, 51, 52,
477	37, 38, 39, 40,   53, 54, 55, 56,
478	41, 42, 43, 44,   57, 58, 59, 60,
479	45, 46, 47, 48,   61, 62, 63, 64,
480};
481
482static const unsigned char itoa64[] =		/* 0..63 => ascii-64 */
483	"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
484
485
486/* =====  Tables that are initialized at run time  ==================== */
487
488
489/* ascii-64 => 0..63 */
490static const unsigned char a64toi[128] = {
491	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
492	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
493	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
494	2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 0, 0, 0, 0, 0, 0,
495	0, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
496	27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 0, 0, 0, 0, 0,
497	0, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52,
498	53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 0, 0, 0, 0, 0,
499};
500
501/* Initial key schedule permutation */
502// static C_block	PC1ROT[64/CHUNKBITS][1<<CHUNKBITS];
503static C_block	*PC1ROT;
504
505/* Subsequent key schedule rotation permutations */
506// static C_block	PC2ROT[2][64/CHUNKBITS][1<<CHUNKBITS];
507static C_block	*PC2ROT[2];
508
509/* Initial permutation/expansion table */
510// static C_block	IE3264[32/CHUNKBITS][1<<CHUNKBITS];
511static C_block	*IE3264;
512
513/* Table that combines the S, P, and E operations.  */
514// static long SPE[2][8][64];
515static long *SPE;
516
517/* compressed/interleaved => final permutation table */
518// static C_block	CF6464[64/CHUNKBITS][1<<CHUNKBITS];
519static C_block	*CF6464;
520
521
522/* ==================================== */
523
524
525static C_block	constdatablock;			/* encryption constant */
526static char	cryptresult[1+4+4+11+1];	/* encrypted result */
527
528/*
529 * Return a pointer to static data consisting of the "setting"
530 * followed by an encryption produced by the "key" and "setting".
531 */
532char *
533crypt(key, setting)
534	register const char *key;
535	register const char *setting;
536{
537	register char *encp;
538	register long i;
539	register int t;
540	long salt;
541	int num_iter, salt_size;
542	C_block keyblock, rsltblock;
543
544	for (i = 0; i < 8; i++) {
545		if ((t = 2*(unsigned char)(*key)) != 0)
546			key++;
547		keyblock.b[i] = t;
548	}
549	if (__crypt_des_setkey((char *)keyblock.b))	/* also initializes "a64toi" */
550		return (NULL);
551
552	encp = &cryptresult[0];
553	switch (*setting) {
554	case _PASSWORD_EFMT1:
555		/*
556		 * Involve the rest of the password 8 characters at a time.
557		 */
558		while (*key) {
559			if (__crypt_des_cipher((char *)&keyblock,
560			    (char *)&keyblock, 0L, 1))
561				return (NULL);
562			for (i = 0; i < 8; i++) {
563				if ((t = 2*(unsigned char)(*key)) != 0)
564					key++;
565				keyblock.b[i] ^= t;
566			}
567			if (__crypt_des_setkey((char *)keyblock.b))
568				return (NULL);
569		}
570
571		*encp++ = *setting++;
572
573		/* get iteration count */
574		num_iter = 0;
575		for (i = 4; --i >= 0; ) {
576			if ((t = (unsigned char)setting[i]) == '\0')
577				t = '.';
578			encp[i] = t;
579			num_iter = (num_iter<<6) | a64toi[t];
580		}
581		setting += 4;
582		encp += 4;
583		salt_size = 4;
584		break;
585	default:
586		num_iter = 25;
587		salt_size = 2;
588	}
589
590	salt = 0;
591	for (i = salt_size; --i >= 0; ) {
592		if ((t = (unsigned char)setting[i]) == '\0')
593			t = '.';
594		encp[i] = t;
595		salt = (salt<<6) | a64toi[t];
596	}
597	encp += salt_size;
598	if (__crypt_des_cipher((char *)&constdatablock, (char *)&rsltblock,
599	    salt, num_iter))
600		return (NULL);
601
602	/*
603	 * Encode the 64 cipher bits as 11 ascii characters.
604	 */
605	i = ((long)((rsltblock.b[0]<<8) | rsltblock.b[1])<<8) | rsltblock.b[2];
606	encp[3] = itoa64[i&0x3f];	i >>= 6;
607	encp[2] = itoa64[i&0x3f];	i >>= 6;
608	encp[1] = itoa64[i&0x3f];	i >>= 6;
609	encp[0] = itoa64[i];		encp += 4;
610	i = ((long)((rsltblock.b[3]<<8) | rsltblock.b[4])<<8) | rsltblock.b[5];
611	encp[3] = itoa64[i&0x3f];	i >>= 6;
612	encp[2] = itoa64[i&0x3f];	i >>= 6;
613	encp[1] = itoa64[i&0x3f];	i >>= 6;
614	encp[0] = itoa64[i];		encp += 4;
615	i = ((long)((rsltblock.b[6])<<8) | rsltblock.b[7])<<2;
616	encp[2] = itoa64[i&0x3f];	i >>= 6;
617	encp[1] = itoa64[i&0x3f];	i >>= 6;
618	encp[0] = itoa64[i];
619
620	encp[3] = 0;
621
622	return (cryptresult);
623}
624
625
626/*
627 * The Key Schedule, filled in by __crypt_des_setkey() or setkey().
628 */
629#define	KS_SIZE	16
630static C_block	KS[KS_SIZE];
631
632/*
633 * Set up the key schedule from the key.
634 */
635__private_extern__ int __crypt_des_setkey(key)
636	register const char *key;
637{
638	register DCL_BLOCK(K, K0, K1);
639	register C_block *ptabp;
640	register int i;
641	static int des_ready = 0;
642
643	if (!des_ready) {
644		init_des();
645		des_ready = 1;
646	}
647
648	PERM6464(K,K0,K1,(unsigned char *)key,PC1ROT);
649	key = (char *)&KS[0];
650	STORE(K&~0x03030303L, K0&~0x03030303L, K1, *(C_block *)key);
651	for (i = 1; i < 16; i++) {
652		key += sizeof(C_block);
653		STORE(K,K0,K1,*(C_block *)key);
654		ptabp = PC2ROT[Rotates[i]-1];
655		PERM6464(K,K0,K1,(unsigned char *)key,ptabp);
656		STORE(K&~0x03030303L, K0&~0x03030303L, K1, *(C_block *)key);
657	}
658	__crypt_des_setkey_called = 1;
659	return (0);
660}
661
662/*
663 * Encrypt (or decrypt if num_iter < 0) the 8 chars at "in" with abs(num_iter)
664 * iterations of DES, using the the given 24-bit salt and the pre-computed key
665 * schedule, and store the resulting 8 chars at "out" (in == out is permitted).
666 *
667 * NOTE: the performance of this routine is critically dependent on your
668 * compiler and machine architecture.
669 */
670__private_extern__ int __crypt_des_cipher(in, out, salt, num_iter)
671	const char *in;
672	char *out;
673	long salt;
674	int num_iter;
675{
676	/* variables that we want in registers, most important first */
677#if defined(pdp11)
678	register int j;
679#endif
680	register long L0, L1, R0, R1, k;
681	register C_block *kp;
682	register int loop_count;
683	ssize_t ks_inc;
684	C_block B;
685
686	L0 = salt;
687	TO_SIX_BIT(salt, L0);	/* convert to 4*(6+2) format */
688
689#if defined(vax) || defined(pdp11)
690	salt = ~salt;	/* "x &~ y" is faster than "x & y". */
691#define	SALT (~salt)
692#else
693#define	SALT salt
694#endif
695
696#if defined(MUST_ALIGN)
697	B.b[0] = in[0]; B.b[1] = in[1]; B.b[2] = in[2]; B.b[3] = in[3];
698	B.b[4] = in[4]; B.b[5] = in[5]; B.b[6] = in[6]; B.b[7] = in[7];
699	LOAD(L,L0,L1,B);
700#else
701	LOAD(L,L0,L1,*(C_block *)in);
702#endif
703	LOADREG(R,R0,R1,L,L0,L1);
704	L0 &= 0x55555555L;
705	L1 &= 0x55555555L;
706	L0 = (L0 << 1) | L1;	/* L0 is the even-numbered input bits */
707	R0 &= 0xaaaaaaaaL;
708	R1 = (R1 >> 1) & 0x55555555L;
709	L1 = R0 | R1;		/* L1 is the odd-numbered input bits */
710	STORE(L,L0,L1,B);
711	PERM3264(L,L0,L1,B.b,IE3264);	/* even bits */
712	PERM3264(R,R0,R1,B.b+4,IE3264);	/* odd bits */
713
714	if (num_iter >= 0)
715	{		/* encryption */
716		kp = &KS[0];
717		ks_inc  = sizeof(*kp);
718	}
719	else
720	{		/* decryption */
721		num_iter = -num_iter;
722		kp = &KS[KS_SIZE-1];
723		ks_inc  = -sizeof(*kp);
724	}
725
726	while (--num_iter >= 0) {
727		loop_count = 8;
728		do {
729
730#define	SPTAB(t, i)	(*(long *)((unsigned char *)t + i*(sizeof(long)/4)))
731#if defined(gould)
732			/* use this if B.b[i] is evaluated just once ... */
733#define	DOXOR(x,y,i)	x^=SPTAB(&SPE[i * 64],B.b[i]); y^=SPTAB(&SPE[(8 * 64) + (i * 64)],B.b[i]);
734#else
735#if defined(pdp11)
736			/* use this if your "long" int indexing is slow */
737#define	DOXOR(x,y,i)	j=B.b[i]; x^=SPTAB(&SPE[i * 64],j); y^=SPTAB(&SPE[(8 * 64) + (i * 64)],j);
738#else
739			/* use this if "k" is allocated to a register ... */
740#define	DOXOR(x,y,i)	k=B.b[i]; x^=SPTAB(&SPE[i * 64],k); y^=SPTAB(&SPE[(8 * 64) + (i * 64)],k);
741#endif
742#endif
743
744#define	CRUNCH(p0, p1, q0, q1)	\
745			k = (q0 ^ q1) & SALT;	\
746			B.b32.i0 = k ^ q0 ^ kp->b32.i0;		\
747			B.b32.i1 = k ^ q1 ^ kp->b32.i1;		\
748			kp = (C_block *)((char *)kp+ks_inc);	\
749							\
750			DOXOR(p0, p1, 0);		\
751			DOXOR(p0, p1, 1);		\
752			DOXOR(p0, p1, 2);		\
753			DOXOR(p0, p1, 3);		\
754			DOXOR(p0, p1, 4);		\
755			DOXOR(p0, p1, 5);		\
756			DOXOR(p0, p1, 6);		\
757			DOXOR(p0, p1, 7);
758
759			CRUNCH(L0, L1, R0, R1);
760			CRUNCH(R0, R1, L0, L1);
761		} while (--loop_count != 0);
762		kp = (C_block *)((char *)kp-(ks_inc*KS_SIZE));
763
764
765		/* swap L and R */
766		L0 ^= R0;  L1 ^= R1;
767		R0 ^= L0;  R1 ^= L1;
768		L0 ^= R0;  L1 ^= R1;
769	}
770
771	/* store the encrypted (or decrypted) result */
772	L0 = ((L0 >> 3) & 0x0f0f0f0fL) | ((L1 << 1) & 0xf0f0f0f0L);
773	L1 = ((R0 >> 3) & 0x0f0f0f0fL) | ((R1 << 1) & 0xf0f0f0f0L);
774	STORE(L,L0,L1,B);
775	PERM6464(L,L0,L1,B.b,CF6464);
776#if defined(MUST_ALIGN)
777	STORE(L,L0,L1,B);
778	out[0] = B.b[0]; out[1] = B.b[1]; out[2] = B.b[2]; out[3] = B.b[3];
779	out[4] = B.b[4]; out[5] = B.b[5]; out[6] = B.b[6]; out[7] = B.b[7];
780#else
781	STORE(L,L0,L1,*(C_block *)out);
782#endif
783	return (0);
784}
785
786
787/*
788 * Initialize various tables.  This need only be done once.  It could even be
789 * done at compile time, if the compiler were capable of that sort of thing.
790 */
791STATIC void init_des()
792{
793	register int i, j;
794	register long k;
795	register int tableno;
796	unsigned char perm[64] = {0};
797
798	/*
799	 * PC1ROT - bit reverse, then PC1, then Rotate, then PC2.
800	 */
801	for (i = 0; i < 64; i++) {
802		if ((k = PC2[i]) == 0)
803			continue;
804		k += Rotates[0]-1;
805		if ((k%28) < Rotates[0]) k -= 28;
806		k = PC1[k];
807		if (k > 0) {
808			k--;
809			k = (k|07) - (k&07);
810			k++;
811		}
812		perm[i] = k;
813	}
814#ifdef DEBUG
815	prtab("pc1tab", perm, 8);
816#endif
817	PC1ROT = (C_block *)calloc(sizeof(C_block), (64/CHUNKBITS) * (1<<CHUNKBITS));
818	for (i = 0; i < 2; i++)
819		PC2ROT[i] = (C_block *)calloc(sizeof(C_block), (64/CHUNKBITS) * (1<<CHUNKBITS));
820	init_perm(PC1ROT, perm, 8, 8);
821
822	/*
823	 * PC2ROT - PC2 inverse, then Rotate (once or twice), then PC2.
824	 */
825	for (j = 0; j < 2; j++) {
826		unsigned char pc2inv[64];
827		for (i = 0; i < 64; i++)
828			perm[i] = pc2inv[i] = 0;
829		for (i = 0; i < 64; i++) {
830			if ((k = PC2[i]) == 0)
831				continue;
832			pc2inv[k-1] = i+1;
833		}
834		for (i = 0; i < 64; i++) {
835			if ((k = PC2[i]) == 0)
836				continue;
837			k += j;
838			if ((k%28) <= j) k -= 28;
839			perm[i] = pc2inv[k];
840		}
841#ifdef DEBUG
842		prtab("pc2tab", perm, 8);
843#endif
844		init_perm(PC2ROT[j], perm, 8, 8);
845	}
846
847	/*
848	 * Bit reverse, then initial permutation, then expansion.
849	 */
850	for (i = 0; i < 8; i++) {
851		for (j = 0; j < 8; j++) {
852			k = (j < 2)? 0: IP[ExpandTr[i*6+j-2]-1];
853			if (k > 32)
854				k -= 32;
855			else if (k > 0)
856				k--;
857			if (k > 0) {
858				k--;
859				k = (k|07) - (k&07);
860				k++;
861			}
862			perm[i*8+j] = k;
863		}
864	}
865#ifdef DEBUG
866	prtab("ietab", perm, 8);
867#endif
868	IE3264 = (C_block *)calloc(sizeof(C_block), (32/CHUNKBITS) * (1<<CHUNKBITS));
869	init_perm(IE3264, perm, 4, 8);
870
871	/*
872	 * Compression, then final permutation, then bit reverse.
873	 */
874	for (i = 0; i < 64; i++) {
875		k = IP[CIFP[i]-1];
876		if (k > 0) {
877			k--;
878			k = (k|07) - (k&07);
879			k++;
880		}
881		perm[k-1] = i+1;
882	}
883#ifdef DEBUG
884	prtab("cftab", perm, 8);
885#endif
886	CF6464 = (C_block *)calloc(sizeof(C_block), (64/CHUNKBITS) * (1<<CHUNKBITS));
887	SPE = (long *)calloc(sizeof(long), 2 * 8 * 64);
888	init_perm(CF6464, perm, 8, 8);
889
890	/*
891	 * SPE table
892	 */
893	for (i = 0; i < 48; i++)
894		perm[i] = P32Tr[ExpandTr[i]-1];
895	for (tableno = 0; tableno < 8; tableno++) {
896		for (j = 0; j < 64; j++)  {
897			unsigned char tmp32[32] = { 0 };
898			k = (((j >> 0) &01) << 5)|
899			    (((j >> 1) &01) << 3)|
900			    (((j >> 2) &01) << 2)|
901			    (((j >> 3) &01) << 1)|
902			    (((j >> 4) &01) << 0)|
903			    (((j >> 5) &01) << 4);
904			k = S[tableno][k];
905			k = (((k >> 3)&01) << 0)|
906			    (((k >> 2)&01) << 1)|
907			    (((k >> 1)&01) << 2)|
908			    (((k >> 0)&01) << 3);
909			for (i = 0; i < 4; i++)
910				tmp32[4 * tableno + i] = (k >> i) & 01;
911			k = 0;
912			for (i = 24; --i >= 0; )
913				k = (k<<1) | tmp32[perm[i]-1];
914			TO_SIX_BIT(SPE[(tableno * 64) + j], k);
915			k = 0;
916			for (i = 24; --i >= 0; )
917				k = (k<<1) | tmp32[perm[i+24]-1];
918			TO_SIX_BIT(SPE[(8 * 64) + (tableno * 64) + j], k);
919		}
920	}
921}
922
923/*
924 * Initialize "perm" to represent transformation "p", which rearranges
925 * (perhaps with expansion and/or contraction) one packed array of bits
926 * (of size "chars_in" characters) into another array (of size "chars_out"
927 * characters).
928 *
929 * "perm" must be all-zeroes on entry to this routine.
930 */
931STATIC void init_perm(perm, p, chars_in, chars_out)
932	C_block *perm;
933	unsigned char p[64];
934	int chars_in, chars_out;
935{
936	register int i, j, k, l;
937
938	for (k = 0; k < chars_out*8; k++) {	/* each output bit position */
939		l = p[k] - 1;		/* where this bit comes from */
940		if (l < 0)
941			continue;	/* output bit is always 0 */
942		i = l>>LGCHUNKBITS;	/* which chunk this bit comes from */
943		l = 1<<(l&(CHUNKBITS-1));	/* mask for this bit */
944		for (j = 0; j < (1<<CHUNKBITS); j++) {	/* each chunk value */
945			if ((j & l) != 0)
946				perm[(i * (1<<CHUNKBITS)) + j].b[k>>3] |= 1<<(k&07);
947		}
948	}
949}
950#endif /* BUILDING_VARIANT */
951
952/*
953 * "setkey" routine (for backwards compatibility)
954 */
955#if __DARWIN_UNIX03
956void setkey(key)
957#else /* !__DARWIN_UNIX03 */
958int setkey(key)
959#endif /* __DARWIN_UNIX03 */
960	register const char *key;
961{
962	register int i, j, k;
963	C_block keyblock;
964
965	for (i = 0; i < 8; i++) {
966		k = 0;
967		for (j = 0; j < 8; j++) {
968			k <<= 1;
969			k |= (unsigned char)*key++;
970		}
971		keyblock.b[i] = k;
972	}
973#if __DARWIN_UNIX03
974	__crypt_des_setkey((char *)keyblock.b);
975#else /* !__DARWIN_UNIX03 */
976	return (__crypt_des_setkey((char *)keyblock.b));
977#endif /* __DARWIN_UNIX03 */
978}
979
980/*
981 * "encrypt" routine (for backwards compatibility)
982 */
983#if __DARWIN_UNIX03
984void encrypt(block, flag)
985#else /* !__DARWIN_UNIX03 */
986int encrypt(block, flag)
987#endif /* __DARWIN_UNIX03 */
988	register char *block;
989	int flag;
990{
991	register int i, j, k;
992	C_block cblock;
993
994	/* Prevent encrypt from crashing if setkey was never called.
995	 * This does not make a good cypher */
996	if (!__crypt_des_setkey_called) {
997		cblock.b32.i0 = cblock.b32.i1 = 0;
998		__crypt_des_setkey((char *)cblock.b);
999	}
1000	for (i = 0; i < 8; i++) {
1001		k = 0;
1002		for (j = 0; j < 8; j++) {
1003			k <<= 1;
1004			k |= (unsigned char)*block++;
1005		}
1006		cblock.b[i] = k;
1007	}
1008	if (__crypt_des_cipher((char *)&cblock, (char *)&cblock, 0L, (flag ? -1: 1)))
1009#if __DARWIN_UNIX03
1010		return;
1011#else /* !__DARWIN_UNIX03 */
1012		return (1);
1013#endif /* __DARWIN_UNIX03 */
1014	for (i = 7; i >= 0; i--) {
1015		k = cblock.b[i];
1016		for (j = 7; j >= 0; j--) {
1017			*--block = k&01;
1018			k >>= 1;
1019		}
1020	}
1021#if !__DARWIN_UNIX03
1022	return (0);
1023#endif /* !__DARWIN_UNIX03 */
1024}
1025
1026#ifndef BUILDING_VARIANT
1027#ifdef DEBUG
1028STATIC void
1029prtab(s, t, num_rows)
1030	char *s;
1031	unsigned char *t;
1032	int num_rows;
1033{
1034	register int i, j;
1035
1036	(void)printf("%s:\n", s);
1037	for (i = 0; i < num_rows; i++) {
1038		for (j = 0; j < 8; j++) {
1039			 (void)printf("%3d", t[i*8+j]);
1040		}
1041		(void)printf("\n");
1042	}
1043	(void)printf("\n");
1044}
1045#endif
1046#endif /* BUILDING_VARIANT */
1047