1 /* src/port/crypt.c */
2 /* $NetBSD: crypt.c,v 1.18 2001/03/01 14:37:35 wiz Exp $ */
3
4 /*
5 * Copyright (c) 1989, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Tom Truscott.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #if defined(LIBC_SCCS) && !defined(lint)
37 #if 0
38 static char sccsid[] = "@(#)crypt.c 8.1.1.1 (Berkeley) 8/18/93";
39 #else
40 __RCSID("$NetBSD: crypt.c,v 1.18 2001/03/01 14:37:35 wiz Exp $");
41 #endif
42 #endif /* not lint */
43
44 #include "c.h"
45
46 #include <limits.h>
47
48 #ifndef WIN32
49 #include <unistd.h>
50 #endif
51
52 static int des_setkey(const char *key);
53 static int des_cipher(const char *in, char *out, long salt, int num_iter);
54
55 /*
56 * UNIX password, and DES, encryption.
57 * By Tom Truscott, trt@rti.rti.org,
58 * from algorithms by Robert W. Baldwin and James Gillogly.
59 *
60 * References:
61 * "Mathematical Cryptology for Computer Scientists and Mathematicians,"
62 * by Wayne Patterson, 1987, ISBN 0-8476-7438-X.
63 *
64 * "Password Security: A Case History," R. Morris and Ken Thompson,
65 * Communications of the ACM, vol. 22, pp. 594-597, Nov. 1979.
66 *
67 * "DES will be Totally Insecure within Ten Years," M.E. Hellman,
68 * IEEE Spectrum, vol. 16, pp. 32-39, July 1979.
69 */
70
71 /* ===== Configuration ==================== */
72
73 /*
74 * define "MUST_ALIGN" if your compiler cannot load/store
75 * long integers at arbitrary (e.g. odd) memory locations.
76 * (Either that or never pass unaligned addresses to des_cipher!)
77 */
78 /* #define MUST_ALIGN */
79
80 #ifdef CHAR_BITS
81 #if CHAR_BITS != 8
82 #error C_block structure assumes 8 bit characters
83 #endif
84 #endif
85
86 /*
87 * define "B64" to be the declaration for a 64 bit integer.
88 * XXX this feature is currently unused, see "endian" comment below.
89 */
90 /* #define B64 int64 */
91
92 /*
93 * define "LARGEDATA" to get faster permutations, by using about 72 kilobytes
94 * of lookup tables. This speeds up des_setkey() and des_cipher(), but has
95 * little effect on crypt().
96 */
97 /* #define LARGEDATA */
98
99 /* compile with "-DSTATIC=void" when profiling */
100 #ifndef STATIC
101 #define STATIC static void
102 #endif
103
104 /*
105 * Define the "int32_t" type for integral type with a width of at least
106 * 32 bits.
107 */
108 typedef int int32_t;
109
110 /* ==================================== */
111
112 #define _PASSWORD_EFMT1 '_' /* extended encryption format */
113
114 /*
115 * Cipher-block representation (Bob Baldwin):
116 *
117 * DES operates on groups of 64 bits, numbered 1..64 (sigh). One
118 * representation is to store one bit per byte in an array of bytes. Bit N of
119 * the NBS spec is stored as the LSB of the Nth byte (index N-1) in the array.
120 * Another representation stores the 64 bits in 8 bytes, with bits 1..8 in the
121 * first byte, 9..16 in the second, and so on. The DES spec apparently has
122 * bit 1 in the MSB of the first byte, but that is particularly noxious so we
123 * bit-reverse each byte so that bit 1 is the LSB of the first byte, bit 8 is
124 * the MSB of the first byte. Specifically, the 64-bit input data and key are
125 * converted to LSB format, and the output 64-bit block is converted back into
126 * MSB format.
127 *
128 * DES operates internally on groups of 32 bits which are expanded to 48 bits
129 * by permutation E and shrunk back to 32 bits by the S boxes. To speed up
130 * the computation, the expansion is applied only once, the expanded
131 * representation is maintained during the encryption, and a compression
132 * permutation is applied only at the end. To speed up the S-box lookups,
133 * the 48 bits are maintained as eight 6 bit groups, one per byte, which
134 * directly feed the eight S-boxes. Within each byte, the 6 bits are the
135 * most significant ones. The low two bits of each byte are zero. (Thus,
136 * bit 1 of the 48 bit E expansion is stored as the "4"-valued bit of the
137 * first byte in the eight byte representation, bit 2 of the 48 bit value is
138 * the "8"-valued bit, and so on.) In fact, a combined "SPE"-box lookup is
139 * used, in which the output is the 64 bit result of an S-box lookup which
140 * has been permuted by P and expanded by E, and is ready for use in the next
141 * iteration. Two 32-bit wide tables, SPE[0] and SPE[1], are used for this
142 * lookup. Since each byte in the 48 bit path is a multiple of four, indexed
143 * lookup of SPE[0] and SPE[1] is simple and fast. The key schedule and
144 * "salt" are also converted to this 8*(6+2) format. The SPE table size is
145 * 8*64*8 = 4K bytes.
146 *
147 * To speed up bit-parallel operations (such as XOR), the 8 byte
148 * representation is "union"ed with 32 bit values "i0" and "i1", and, on
149 * machines which support it, a 64 bit value "b64". This data structure,
150 * "C_block", has two problems. First, alignment restrictions must be
151 * honored. Second, the byte-order (e.g. little-endian or big-endian) of
152 * the architecture becomes visible.
153 *
154 * The byte-order problem is unfortunate, since on the one hand it is good
155 * to have a machine-independent C_block representation (bits 1..8 in the
156 * first byte, etc.), and on the other hand it is good for the LSB of the
157 * first byte to be the LSB of i0. We cannot have both these things, so we
158 * currently use the "little-endian" representation and avoid any multi-byte
159 * operations that depend on byte order. This largely precludes use of the
160 * 64-bit datatype since the relative order of i0 and i1 are unknown. It
161 * also inhibits grouping the SPE table to look up 12 bits at a time. (The
162 * 12 bits can be stored in a 16-bit field with 3 low-order zeroes and 1
163 * high-order zero, providing fast indexing into a 64-bit wide SPE.) On the
164 * other hand, 64-bit datatypes are currently rare, and a 12-bit SPE lookup
165 * requires a 128 kilobyte table, so perhaps this is not a big loss.
166 *
167 * Permutation representation (Jim Gillogly):
168 *
169 * A transformation is defined by its effect on each of the 8 bytes of the
170 * 64-bit input. For each byte we give a 64-bit output that has the bits in
171 * the input distributed appropriately. The transformation is then the OR
172 * of the 8 sets of 64-bits. This uses 8*256*8 = 16K bytes of storage for
173 * each transformation. Unless LARGEDATA is defined, however, a more compact
174 * table is used which looks up 16 4-bit "chunks" rather than 8 8-bit chunks.
175 * The smaller table uses 16*16*8 = 2K bytes for each transformation. This
176 * is slower but tolerable, particularly for password encryption in which
177 * the SPE transformation is iterated many times. The small tables total 9K
178 * bytes, the large tables total 72K bytes.
179 *
180 * The transformations used are:
181 * IE3264: MSB->LSB conversion, initial permutation, and expansion.
182 * This is done by collecting the 32 even-numbered bits and applying
183 * a 32->64 bit transformation, and then collecting the 32 odd-numbered
184 * bits and applying the same transformation. Since there are only
185 * 32 input bits, the IE3264 transformation table is half the size of
186 * the usual table.
187 * CF6464: Compression, final permutation, and LSB->MSB conversion.
188 * This is done by two trivial 48->32 bit compressions to obtain
189 * a 64-bit block (the bit numbering is given in the "CIFP" table)
190 * followed by a 64->64 bit "cleanup" transformation. (It would
191 * be possible to group the bits in the 64-bit block so that 2
192 * identical 32->32 bit transformations could be used instead,
193 * saving a factor of 4 in space and possibly 2 in time, but
194 * byte-ordering and other complications rear their ugly head.
195 * Similar opportunities/problems arise in the key schedule
196 * transforms.)
197 * PC1ROT: MSB->LSB, PC1 permutation, rotate, and PC2 permutation.
198 * This admittedly baroque 64->64 bit transformation is used to
199 * produce the first code (in 8*(6+2) format) of the key schedule.
200 * PC2ROT[0]: Inverse PC2 permutation, rotate, and PC2 permutation.
201 * It would be possible to define 15 more transformations, each
202 * with a different rotation, to generate the entire key schedule.
203 * To save space, however, we instead permute each code into the
204 * next by using a transformation that "undoes" the PC2 permutation,
205 * rotates the code, and then applies PC2. Unfortunately, PC2
206 * transforms 56 bits into 48 bits, dropping 8 bits, so PC2 is not
207 * invertible. We get around that problem by using a modified PC2
208 * which retains the 8 otherwise-lost bits in the unused low-order
209 * bits of each byte. The low-order bits are cleared when the
210 * codes are stored into the key schedule.
211 * PC2ROT[1]: Same as PC2ROT[0], but with two rotations.
212 * This is faster than applying PC2ROT[0] twice,
213 *
214 * The Bell Labs "salt" (Bob Baldwin):
215 *
216 * The salting is a simple permutation applied to the 48-bit result of E.
217 * Specifically, if bit i (1 <= i <= 24) of the salt is set then bits i and
218 * i+24 of the result are swapped. The salt is thus a 24 bit number, with
219 * 16777216 possible values. (The original salt was 12 bits and could not
220 * swap bits 13..24 with 36..48.)
221 *
222 * It is possible, but ugly, to warp the SPE table to account for the salt
223 * permutation. Fortunately, the conditional bit swapping requires only
224 * about four machine instructions and can be done on-the-fly with about an
225 * 8% performance penalty.
226 */
227
228 typedef union
229 {
230 unsigned char b[8];
231 struct
232 {
233 int32_t i0;
234 int32_t i1;
235 } b32;
236 #if defined(B64)
237 B64 b64;
238 #endif
239 } C_block;
240
241 /*
242 * Convert twenty-four-bit long in host-order
243 * to six bits (and 2 low-order zeroes) per char little-endian format.
244 */
245 #define TO_SIX_BIT(rslt, src) { \
246 C_block cvt; \
247 cvt.b[0] = src; src >>= 6; \
248 cvt.b[1] = src; src >>= 6; \
249 cvt.b[2] = src; src >>= 6; \
250 cvt.b[3] = src; \
251 rslt = (cvt.b32.i0 & 0x3f3f3f3fL) << 2; \
252 }
253
254 /*
255 * These macros may someday permit efficient use of 64-bit integers.
256 */
257 #define ZERO(d,d0,d1) d0 = 0, d1 = 0
258 #define LOAD(d,d0,d1,bl) d0 = (bl).b32.i0, d1 = (bl).b32.i1
259 #define LOADREG(d,d0,d1,s,s0,s1) d0 = s0, d1 = s1
260 #define OR(d,d0,d1,bl) d0 |= (bl).b32.i0, d1 |= (bl).b32.i1
261 #define STORE(s,s0,s1,bl) (bl).b32.i0 = s0, (bl).b32.i1 = s1
262 #define DCL_BLOCK(d,d0,d1) int32_t d0, d1
263
264 #if defined(LARGEDATA)
265 /* Waste memory like crazy. Also, do permutations in line */
266 #define LGCHUNKBITS 3
267 #define CHUNKBITS (1<<LGCHUNKBITS)
268 #define PERM6464(d,d0,d1,cpp,p) \
269 LOAD(d,d0,d1,(p)[(0<<CHUNKBITS)+(cpp)[0]]); \
270 OR (d,d0,d1,(p)[(1<<CHUNKBITS)+(cpp)[1]]); \
271 OR (d,d0,d1,(p)[(2<<CHUNKBITS)+(cpp)[2]]); \
272 OR (d,d0,d1,(p)[(3<<CHUNKBITS)+(cpp)[3]]); \
273 OR (d,d0,d1,(p)[(4<<CHUNKBITS)+(cpp)[4]]); \
274 OR (d,d0,d1,(p)[(5<<CHUNKBITS)+(cpp)[5]]); \
275 OR (d,d0,d1,(p)[(6<<CHUNKBITS)+(cpp)[6]]); \
276 OR (d,d0,d1,(p)[(7<<CHUNKBITS)+(cpp)[7]]);
277 #define PERM3264(d,d0,d1,cpp,p) \
278 LOAD(d,d0,d1,(p)[(0<<CHUNKBITS)+(cpp)[0]]); \
279 OR (d,d0,d1,(p)[(1<<CHUNKBITS)+(cpp)[1]]); \
280 OR (d,d0,d1,(p)[(2<<CHUNKBITS)+(cpp)[2]]); \
281 OR (d,d0,d1,(p)[(3<<CHUNKBITS)+(cpp)[3]]);
282 #else
283 /* "small data" */
284 #define LGCHUNKBITS 2
285 #define CHUNKBITS (1<<LGCHUNKBITS)
286 #define PERM6464(d,d0,d1,cpp,p) \
287 { C_block tblk; permute(cpp,&tblk,p,8); LOAD (d,d0,d1,tblk); }
288 #define PERM3264(d,d0,d1,cpp,p) \
289 { C_block tblk; permute(cpp,&tblk,p,4); LOAD (d,d0,d1,tblk); }
290 #endif /* LARGEDATA */
291
292 STATIC init_des(void);
293 STATIC init_perm(C_block[64 / CHUNKBITS][1 << CHUNKBITS], unsigned char[64], int, int);
294
295 #ifndef LARGEDATA
296 STATIC permute(unsigned char *, C_block *, C_block *, int);
297 #endif
298 #ifdef DEBUG
299 STATIC prtab(char *, unsigned char *, int);
300 #endif
301
302
303 #ifndef LARGEDATA
304 STATIC
permute(cp,out,p,chars_in)305 permute(cp, out, p, chars_in)
306 unsigned char *cp;
307 C_block *out;
308 C_block *p;
309 int chars_in;
310 {
311 DCL_BLOCK(D, D0, D1);
312 C_block *tp;
313 int t;
314
315 ZERO(D, D0, D1);
316 do
317 {
318 t = *cp++;
319 tp = &p[t & 0xf];
320 OR(D, D0, D1, *tp);
321 p += (1 << CHUNKBITS);
322 tp = &p[t >> 4];
323 OR(D, D0, D1, *tp);
324 p += (1 << CHUNKBITS);
325 } while (--chars_in > 0);
326 STORE(D, D0, D1, *out);
327 }
328 #endif /* LARGEDATA */
329
330
331 /* ===== (mostly) Standard DES Tables ==================== */
332
333 static const unsigned char IP[] = { /* initial permutation */
334 58, 50, 42, 34, 26, 18, 10, 2,
335 60, 52, 44, 36, 28, 20, 12, 4,
336 62, 54, 46, 38, 30, 22, 14, 6,
337 64, 56, 48, 40, 32, 24, 16, 8,
338 57, 49, 41, 33, 25, 17, 9, 1,
339 59, 51, 43, 35, 27, 19, 11, 3,
340 61, 53, 45, 37, 29, 21, 13, 5,
341 63, 55, 47, 39, 31, 23, 15, 7,
342 };
343
344 /* The final permutation is the inverse of IP - no table is necessary */
345
346 static const unsigned char ExpandTr[] = { /* expansion operation */
347 32, 1, 2, 3, 4, 5,
348 4, 5, 6, 7, 8, 9,
349 8, 9, 10, 11, 12, 13,
350 12, 13, 14, 15, 16, 17,
351 16, 17, 18, 19, 20, 21,
352 20, 21, 22, 23, 24, 25,
353 24, 25, 26, 27, 28, 29,
354 28, 29, 30, 31, 32, 1,
355 };
356
357 static const unsigned char PC1[] = { /* permuted choice table 1 */
358 57, 49, 41, 33, 25, 17, 9,
359 1, 58, 50, 42, 34, 26, 18,
360 10, 2, 59, 51, 43, 35, 27,
361 19, 11, 3, 60, 52, 44, 36,
362
363 63, 55, 47, 39, 31, 23, 15,
364 7, 62, 54, 46, 38, 30, 22,
365 14, 6, 61, 53, 45, 37, 29,
366 21, 13, 5, 28, 20, 12, 4,
367 };
368
369 static const unsigned char Rotates[] = { /* PC1 rotation schedule */
370 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1,
371 };
372
373 /* note: each "row" of PC2 is left-padded with bits that make it invertible */
374 static const unsigned char PC2[] = { /* permuted choice table 2 */
375 9, 18, 14, 17, 11, 24, 1, 5,
376 22, 25, 3, 28, 15, 6, 21, 10,
377 35, 38, 23, 19, 12, 4, 26, 8,
378 43, 54, 16, 7, 27, 20, 13, 2,
379
380 0, 0, 41, 52, 31, 37, 47, 55,
381 0, 0, 30, 40, 51, 45, 33, 48,
382 0, 0, 44, 49, 39, 56, 34, 53,
383 0, 0, 46, 42, 50, 36, 29, 32,
384 };
385
386 static const unsigned char S[8][64] = { /* 48->32 bit substitution tables */
387 /* S[1] */
388 {14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7,
389 0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8,
390 4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0,
391 15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13},
392 /* S[2] */
393 {15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10,
394 3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5,
395 0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15,
396 13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9},
397 /* S[3] */
398 {10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8,
399 13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1,
400 13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7,
401 1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12},
402 /* S[4] */
403 {7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15,
404 13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9,
405 10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4,
406 3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14},
407 /* S[5] */
408 {2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9,
409 14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6,
410 4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14,
411 11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3},
412 /* S[6] */
413 {12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11,
414 10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8,
415 9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6,
416 4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13},
417 /* S[7] */
418 {4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1,
419 13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6,
420 1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2,
421 6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12},
422 /* S[8] */
423 {13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7,
424 1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2,
425 7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8,
426 2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11}
427 };
428
429 static const unsigned char P32Tr[] = { /* 32-bit permutation function */
430 16, 7, 20, 21,
431 29, 12, 28, 17,
432 1, 15, 23, 26,
433 5, 18, 31, 10,
434 2, 8, 24, 14,
435 32, 27, 3, 9,
436 19, 13, 30, 6,
437 22, 11, 4, 25,
438 };
439
440 static const unsigned char CIFP[] = { /* compressed/interleaved permutation */
441 1, 2, 3, 4, 17, 18, 19, 20,
442 5, 6, 7, 8, 21, 22, 23, 24,
443 9, 10, 11, 12, 25, 26, 27, 28,
444 13, 14, 15, 16, 29, 30, 31, 32,
445
446 33, 34, 35, 36, 49, 50, 51, 52,
447 37, 38, 39, 40, 53, 54, 55, 56,
448 41, 42, 43, 44, 57, 58, 59, 60,
449 45, 46, 47, 48, 61, 62, 63, 64,
450 };
451
452 static const unsigned char itoa64[] = /* 0..63 => ascii-64 */
453 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
454
455
456 /* ===== Tables that are initialized at run time ==================== */
457
458
459 static unsigned char a64toi[128]; /* ascii-64 => 0..63 */
460
461 /* Initial key schedule permutation */
462 static C_block PC1ROT[64 / CHUNKBITS][1 << CHUNKBITS];
463
464 /* Subsequent key schedule rotation permutations */
465 static C_block PC2ROT[2][64 / CHUNKBITS][1 << CHUNKBITS];
466
467 /* Initial permutation/expansion table */
468 static C_block IE3264[32 / CHUNKBITS][1 << CHUNKBITS];
469
470 /* Table that combines the S, P, and E operations. */
471 static int32_t SPE[2][8][64];
472
473 /* compressed/interleaved => final permutation table */
474 static C_block CF6464[64 / CHUNKBITS][1 << CHUNKBITS];
475
476
477 /* ==================================== */
478
479
480 static C_block constdatablock; /* encryption constant */
481 static char cryptresult[1 + 4 + 4 + 11 + 1]; /* encrypted result */
482
483 extern char *__md5crypt(const char *, const char *); /* XXX */
484 extern char *__bcrypt(const char *, const char *); /* XXX */
485
486
487 /*
488 * Return a pointer to static data consisting of the "setting"
489 * followed by an encryption produced by the "key" and "setting".
490 */
491 char *
crypt(key,setting)492 crypt(key, setting)
493 const char *key;
494 const char *setting;
495 {
496 char *encp;
497 int32_t i;
498 int t;
499 int32_t salt;
500 int num_iter,
501 salt_size;
502 C_block keyblock,
503 rsltblock;
504
505 #if 0
506 /* Non-DES encryption schemes hook in here. */
507 if (setting[0] == _PASSWORD_NONDES)
508 {
509 switch (setting[1])
510 {
511 case '2':
512 return (__bcrypt(key, setting));
513 case '1':
514 default:
515 return (__md5crypt(key, setting));
516 }
517 }
518 #endif
519
520 for (i = 0; i < 8; i++)
521 {
522 if ((t = 2 * (unsigned char) (*key)) != 0)
523 key++;
524 keyblock.b[i] = t;
525 }
526 if (des_setkey((char *) keyblock.b)) /* also initializes "a64toi" */
527 return (NULL);
528
529 encp = &cryptresult[0];
530 switch (*setting)
531 {
532 case _PASSWORD_EFMT1:
533
534 /*
535 * Involve the rest of the password 8 characters at a time.
536 */
537 while (*key)
538 {
539 if (des_cipher((char *) (void *) &keyblock,
540 (char *) (void *) &keyblock, 0L, 1))
541 return (NULL);
542 for (i = 0; i < 8; i++)
543 {
544 if ((t = 2 * (unsigned char) (*key)) != 0)
545 key++;
546 keyblock.b[i] ^= t;
547 }
548 if (des_setkey((char *) keyblock.b))
549 return (NULL);
550 }
551
552 *encp++ = *setting++;
553
554 /* get iteration count */
555 num_iter = 0;
556 for (i = 4; --i >= 0;)
557 {
558 if ((t = (unsigned char) setting[i]) == '\0')
559 t = '.';
560 encp[i] = t;
561 num_iter = (num_iter << 6) | a64toi[t];
562 }
563 setting += 4;
564 encp += 4;
565 salt_size = 4;
566 break;
567 default:
568 num_iter = 25;
569 salt_size = 2;
570 }
571
572 salt = 0;
573 for (i = salt_size; --i >= 0;)
574 {
575 if ((t = (unsigned char) setting[i]) == '\0')
576 t = '.';
577 encp[i] = t;
578 salt = (salt << 6) | a64toi[t];
579 }
580 encp += salt_size;
581 if (des_cipher((char *) (void *) &constdatablock,
582 (char *) (void *) &rsltblock, salt, num_iter))
583 return (NULL);
584
585 /*
586 * Encode the 64 cipher bits as 11 ascii characters.
587 */
588 i = ((int32_t) ((rsltblock.b[0] << 8) | rsltblock.b[1]) << 8) |
589 rsltblock.b[2];
590 encp[3] = itoa64[i & 0x3f];
591 i >>= 6;
592 encp[2] = itoa64[i & 0x3f];
593 i >>= 6;
594 encp[1] = itoa64[i & 0x3f];
595 i >>= 6;
596 encp[0] = itoa64[i];
597 encp += 4;
598 i = ((int32_t) ((rsltblock.b[3] << 8) | rsltblock.b[4]) << 8) |
599 rsltblock.b[5];
600 encp[3] = itoa64[i & 0x3f];
601 i >>= 6;
602 encp[2] = itoa64[i & 0x3f];
603 i >>= 6;
604 encp[1] = itoa64[i & 0x3f];
605 i >>= 6;
606 encp[0] = itoa64[i];
607 encp += 4;
608 i = ((int32_t) ((rsltblock.b[6]) << 8) | rsltblock.b[7]) << 2;
609 encp[2] = itoa64[i & 0x3f];
610 i >>= 6;
611 encp[1] = itoa64[i & 0x3f];
612 i >>= 6;
613 encp[0] = itoa64[i];
614
615 encp[3] = 0;
616
617 return (cryptresult);
618 }
619
620
621 /*
622 * The Key Schedule, filled in by des_setkey() or setkey().
623 */
624 #define KS_SIZE 16
625 static C_block KS[KS_SIZE];
626
627 static volatile int des_ready = 0;
628
629 /*
630 * Set up the key schedule from the key.
631 */
632 static int
des_setkey(key)633 des_setkey(key)
634 const char *key;
635 {
636 DCL_BLOCK(K, K0, K1);
637 C_block *ptabp;
638 int i;
639
640 if (!des_ready)
641 init_des();
642
643 PERM6464(K, K0, K1, (unsigned char *) key, (C_block *) PC1ROT);
644 key = (char *) &KS[0];
645 STORE(K & ~0x03030303L, K0 & ~0x03030303L, K1, *(C_block *) key);
646 for (i = 1; i < 16; i++)
647 {
648 key += sizeof(C_block);
649 STORE(K, K0, K1, *(C_block *) key);
650 ptabp = (C_block *) PC2ROT[Rotates[i] - 1];
651 PERM6464(K, K0, K1, (unsigned char *) key, ptabp);
652 STORE(K & ~0x03030303L, K0 & ~0x03030303L, K1, *(C_block *) key);
653 }
654 return (0);
655 }
656
657 /*
658 * Encrypt (or decrypt if num_iter < 0) the 8 chars at "in" with abs(num_iter)
659 * iterations of DES, using the given 24-bit salt and the pre-computed key
660 * schedule, and store the resulting 8 chars at "out" (in == out is permitted).
661 *
662 * NOTE: the performance of this routine is critically dependent on your
663 * compiler and machine architecture.
664 */
665 static int
des_cipher(in,out,salt,num_iter)666 des_cipher(in, out, salt, num_iter)
667 const char *in;
668 char *out;
669 long salt;
670 int num_iter;
671 {
672 /* variables that we want in registers, most important first */
673 #if defined(pdp11)
674 int j;
675 #endif
676 int32_t L0,
677 L1,
678 R0,
679 R1,
680 k;
681 C_block *kp;
682 int ks_inc,
683 loop_count;
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];
698 B.b[1] = in[1];
699 B.b[2] = in[2];
700 B.b[3] = in[3];
701 B.b[4] = in[4];
702 B.b[5] = in[5];
703 B.b[6] = in[6];
704 B.b[7] = in[7];
705 LOAD(L, L0, L1, B);
706 #else
707 LOAD(L, L0, L1, *(C_block *) in);
708 #endif
709 LOADREG(R, R0, R1, L, L0, L1);
710 L0 &= 0x55555555L;
711 L1 &= 0x55555555L;
712 L0 = (L0 << 1) | L1; /* L0 is the even-numbered input bits */
713 R0 &= 0xaaaaaaaaL;
714 R1 = (R1 >> 1) & 0x55555555L;
715 L1 = R0 | R1; /* L1 is the odd-numbered input bits */
716 STORE(L, L0, L1, B);
717 PERM3264(L, L0, L1, B.b, (C_block *) IE3264); /* even bits */
718 PERM3264(R, R0, R1, B.b + 4, (C_block *) IE3264); /* odd bits */
719
720 if (num_iter >= 0)
721 { /* encryption */
722 kp = &KS[0];
723 ks_inc = sizeof(*kp);
724 }
725 else
726 { /* decryption */
727 num_iter = -num_iter;
728 kp = &KS[KS_SIZE - 1];
729 ks_inc = -(long) sizeof(*kp);
730 }
731
732 while (--num_iter >= 0)
733 {
734 loop_count = 8;
735 do
736 {
737
738 #define SPTAB(t, i) \
739 (*(int32_t *)((unsigned char *)(t) + (i)*(sizeof(int32_t)/4)))
740 #if defined(gould)
741 /* use this if B.b[i] is evaluated just once ... */
742 #define DOXOR(x,y,i) x^=SPTAB(SPE[0][i],B.b[i]); y^=SPTAB(SPE[1][i],B.b[i]);
743 #else
744 #if defined(pdp11)
745 /* use this if your "long" int indexing is slow */
746 #define DOXOR(x,y,i) j=B.b[i]; x^=SPTAB(SPE[0][i],j); y^=SPTAB(SPE[1][i],j);
747 #else
748 /* use this if "k" is allocated to a register ... */
749 #define DOXOR(x,y,i) k=B.b[i]; x^=SPTAB(SPE[0][i],k); y^=SPTAB(SPE[1][i],k);
750 #endif
751 #endif
752
753 #define CRUNCH(p0, p1, q0, q1) \
754 k = ((q0) ^ (q1)) & SALT; \
755 B.b32.i0 = k ^ (q0) ^ kp->b32.i0; \
756 B.b32.i1 = k ^ (q1) ^ kp->b32.i1; \
757 kp = (C_block *)((char *)kp+ks_inc); \
758 \
759 DOXOR(p0, p1, 0); \
760 DOXOR(p0, p1, 1); \
761 DOXOR(p0, p1, 2); \
762 DOXOR(p0, p1, 3); \
763 DOXOR(p0, p1, 4); \
764 DOXOR(p0, p1, 5); \
765 DOXOR(p0, p1, 6); \
766 DOXOR(p0, p1, 7);
767
768 CRUNCH(L0, L1, R0, R1);
769 CRUNCH(R0, R1, L0, L1);
770 } while (--loop_count != 0);
771 kp = (C_block *) ((char *) kp - (ks_inc * KS_SIZE));
772
773
774 /* swap L and R */
775 L0 ^= R0;
776 L1 ^= R1;
777 R0 ^= L0;
778 R1 ^= L1;
779 L0 ^= R0;
780 L1 ^= R1;
781 }
782
783 /* store the encrypted (or decrypted) result */
784 L0 = ((L0 >> 3) & 0x0f0f0f0fL) | ((L1 << 1) & 0xf0f0f0f0L);
785 L1 = ((R0 >> 3) & 0x0f0f0f0fL) | ((R1 << 1) & 0xf0f0f0f0L);
786 STORE(L, L0, L1, B);
787 PERM6464(L, L0, L1, B.b, (C_block *) CF6464);
788 #if defined(MUST_ALIGN)
789 STORE(L, L0, L1, B);
790 out[0] = B.b[0];
791 out[1] = B.b[1];
792 out[2] = B.b[2];
793 out[3] = B.b[3];
794 out[4] = B.b[4];
795 out[5] = B.b[5];
796 out[6] = B.b[6];
797 out[7] = B.b[7];
798 #else
799 STORE(L, L0, L1, *(C_block *) out);
800 #endif
801 return (0);
802 }
803
804
805 /*
806 * Initialize various tables. This need only be done once. It could even be
807 * done at compile time, if the compiler were capable of that sort of thing.
808 */
809 STATIC
init_des()810 init_des()
811 {
812 int i,
813 j;
814 int32_t k;
815 int tableno;
816 static unsigned char perm[64],
817 tmp32[32]; /* "static" for speed */
818
819 /* static volatile long init_start = 0; not used */
820
821 /*
822 * table that converts chars "./0-9A-Za-z"to integers 0-63.
823 */
824 for (i = 0; i < 64; i++)
825 a64toi[itoa64[i]] = i;
826
827 /*
828 * PC1ROT - bit reverse, then PC1, then Rotate, then PC2.
829 */
830 for (i = 0; i < 64; i++)
831 perm[i] = 0;
832 for (i = 0; i < 64; i++)
833 {
834 if ((k = PC2[i]) == 0)
835 continue;
836 k += Rotates[0] - 1;
837 if ((k % 28) < Rotates[0])
838 k -= 28;
839 k = PC1[k];
840 if (k > 0)
841 {
842 k--;
843 k = (k | 07) - (k & 07);
844 k++;
845 }
846 perm[i] = k;
847 }
848 #ifdef DEBUG
849 prtab("pc1tab", perm, 8);
850 #endif
851 init_perm(PC1ROT, perm, 8, 8);
852
853 /*
854 * PC2ROT - PC2 inverse, then Rotate (once or twice), then PC2.
855 */
856 for (j = 0; j < 2; j++)
857 {
858 unsigned char pc2inv[64];
859
860 for (i = 0; i < 64; i++)
861 perm[i] = pc2inv[i] = 0;
862 for (i = 0; i < 64; i++)
863 {
864 if ((k = PC2[i]) == 0)
865 continue;
866 pc2inv[k - 1] = i + 1;
867 }
868 for (i = 0; i < 64; i++)
869 {
870 if ((k = PC2[i]) == 0)
871 continue;
872 k += j;
873 if ((k % 28) <= j)
874 k -= 28;
875 perm[i] = pc2inv[k];
876 }
877 #ifdef DEBUG
878 prtab("pc2tab", perm, 8);
879 #endif
880 init_perm(PC2ROT[j], perm, 8, 8);
881 }
882
883 /*
884 * Bit reverse, then initial permutation, then expansion.
885 */
886 for (i = 0; i < 8; i++)
887 {
888 for (j = 0; j < 8; j++)
889 {
890 k = (j < 2) ? 0 : IP[ExpandTr[i * 6 + j - 2] - 1];
891 if (k > 32)
892 k -= 32;
893 else if (k > 0)
894 k--;
895 if (k > 0)
896 {
897 k--;
898 k = (k | 07) - (k & 07);
899 k++;
900 }
901 perm[i * 8 + j] = k;
902 }
903 }
904 #ifdef DEBUG
905 prtab("ietab", perm, 8);
906 #endif
907 init_perm(IE3264, perm, 4, 8);
908
909 /*
910 * Compression, then final permutation, then bit reverse.
911 */
912 for (i = 0; i < 64; i++)
913 {
914 k = IP[CIFP[i] - 1];
915 if (k > 0)
916 {
917 k--;
918 k = (k | 07) - (k & 07);
919 k++;
920 }
921 perm[k - 1] = i + 1;
922 }
923 #ifdef DEBUG
924 prtab("cftab", perm, 8);
925 #endif
926 init_perm(CF6464, perm, 8, 8);
927
928 /*
929 * SPE table
930 */
931 for (i = 0; i < 48; i++)
932 perm[i] = P32Tr[ExpandTr[i] - 1];
933 for (tableno = 0; tableno < 8; tableno++)
934 {
935 for (j = 0; j < 64; j++)
936 {
937 k = (((j >> 0) & 01) << 5) |
938 (((j >> 1) & 01) << 3) |
939 (((j >> 2) & 01) << 2) |
940 (((j >> 3) & 01) << 1) |
941 (((j >> 4) & 01) << 0) |
942 (((j >> 5) & 01) << 4);
943 k = S[tableno][k];
944 k = (((k >> 3) & 01) << 0) |
945 (((k >> 2) & 01) << 1) |
946 (((k >> 1) & 01) << 2) |
947 (((k >> 0) & 01) << 3);
948 for (i = 0; i < 32; i++)
949 tmp32[i] = 0;
950 for (i = 0; i < 4; i++)
951 tmp32[4 * tableno + i] = (k >> i) & 01;
952 k = 0;
953 for (i = 24; --i >= 0;)
954 k = (k << 1) | tmp32[perm[i] - 1];
955 TO_SIX_BIT(SPE[0][tableno][j], k);
956 k = 0;
957 for (i = 24; --i >= 0;)
958 k = (k << 1) | tmp32[perm[i + 24] - 1];
959 TO_SIX_BIT(SPE[1][tableno][j], k);
960 }
961 }
962
963 des_ready = 1;
964 }
965
966 /*
967 * Initialize "perm" to represent transformation "p", which rearranges
968 * (perhaps with expansion and/or contraction) one packed array of bits
969 * (of size "chars_in" characters) into another array (of size "chars_out"
970 * characters).
971 *
972 * "perm" must be all-zeroes on entry to this routine.
973 */
974 STATIC
init_perm(perm,p,chars_in,chars_out)975 init_perm(perm, p, chars_in, chars_out)
976 C_block perm[64 / CHUNKBITS][1 << CHUNKBITS];
977 unsigned char p[64];
978 int chars_in,
979 chars_out;
980 {
981 int i,
982 j,
983 k,
984 l;
985
986 for (k = 0; k < chars_out * 8; k++)
987 { /* each output bit position */
988 l = p[k] - 1; /* where this bit comes from */
989 if (l < 0)
990 continue; /* output bit is always 0 */
991 i = l >> LGCHUNKBITS; /* which chunk this bit comes from */
992 l = 1 << (l & (CHUNKBITS - 1)); /* mask for this bit */
993 for (j = 0; j < (1 << CHUNKBITS); j++)
994 { /* each chunk value */
995 if ((j & l) != 0)
996 perm[i][j].b[k >> 3] |= 1 << (k & 07);
997 }
998 }
999 }
1000
1001 /*
1002 * "setkey" routine (for backwards compatibility)
1003 */
1004 #ifdef NOT_USED
1005 int
setkey(key)1006 setkey(key)
1007 const char *key;
1008 {
1009 int i,
1010 j,
1011 k;
1012 C_block keyblock;
1013
1014 for (i = 0; i < 8; i++)
1015 {
1016 k = 0;
1017 for (j = 0; j < 8; j++)
1018 {
1019 k <<= 1;
1020 k |= (unsigned char) *key++;
1021 }
1022 keyblock.b[i] = k;
1023 }
1024 return (des_setkey((char *) keyblock.b));
1025 }
1026
1027 /*
1028 * "encrypt" routine (for backwards compatibility)
1029 */
1030 static int
encrypt(block,flag)1031 encrypt(block, flag)
1032 char *block;
1033 int flag;
1034 {
1035 int i,
1036 j,
1037 k;
1038 C_block cblock;
1039
1040 for (i = 0; i < 8; i++)
1041 {
1042 k = 0;
1043 for (j = 0; j < 8; j++)
1044 {
1045 k <<= 1;
1046 k |= (unsigned char) *block++;
1047 }
1048 cblock.b[i] = k;
1049 }
1050 if (des_cipher((char *) &cblock, (char *) &cblock, 0L, (flag ? -1 : 1)))
1051 return (1);
1052 for (i = 7; i >= 0; i--)
1053 {
1054 k = cblock.b[i];
1055 for (j = 7; j >= 0; j--)
1056 {
1057 *--block = k & 01;
1058 k >>= 1;
1059 }
1060 }
1061 return (0);
1062 }
1063 #endif
1064
1065 #ifdef DEBUG
1066 STATIC
prtab(s,t,num_rows)1067 prtab(s, t, num_rows)
1068 char *s;
1069 unsigned char *t;
1070 int num_rows;
1071 {
1072 int i,
1073 j;
1074
1075 (void) printf("%s:\n", s);
1076 for (i = 0; i < num_rows; i++)
1077 {
1078 for (j = 0; j < 8; j++)
1079 (void) printf("%3d", t[i * 8 + j]);
1080 (void) printf("\n");
1081 }
1082 (void) printf("\n");
1083 }
1084
1085 #endif
1086