1 /* $NetBSD: crypt.c,v 1.5 1995/02/19 12:19:03 cgd Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Tom Truscott. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #if defined(LIBC_SCCS) && !defined(lint) 40 #if 0 41 static char sccsid[] = "@(#)crypt.c 8.1.1.1 (Berkeley) 8/18/93"; 42 #endif 43 static char rcsid[] = "$NetBSD: crypt.c,v 1.5 1995/02/19 12:19:03 cgd Exp $"; 44 #endif /* LIBC_SCCS and not lint */ 45 46 #include <unistd.h> 47 #include <limits.h> 48 #include <pwd.h> 49 50 /* 51 * UNIX password, and DES, encryption. 52 * By Tom Truscott, trt@rti.rti.org, 53 * from algorithms by Robert W. Baldwin and James Gillogly. 54 * 55 * References: 56 * "Mathematical Cryptology for Computer Scientists and Mathematicians," 57 * by Wayne Patterson, 1987, ISBN 0-8476-7438-X. 58 * 59 * "Password Security: A Case History," R. Morris and Ken Thompson, 60 * Communications of the ACM, vol. 22, pp. 594-597, Nov. 1979. 61 * 62 * "DES will be Totally Insecure within Ten Years," M.E. Hellman, 63 * IEEE Spectrum, vol. 16, pp. 32-39, July 1979. 64 */ 65 66 /* ===== Configuration ==================== */ 67 68 /* 69 * define "MUST_ALIGN" if your compiler cannot load/store 70 * long integers at arbitrary (e.g. odd) memory locations. 71 * (Either that or never pass unaligned addresses to des_cipher!) 72 */ 73 #if !defined(vax) 74 #define MUST_ALIGN 75 #endif 76 77 #ifdef CHAR_BITS 78 #if CHAR_BITS != 8 79 #error C_block structure assumes 8 bit characters 80 #endif 81 #endif 82 83 /* 84 * define "B64" to be the declaration for a 64 bit integer. 85 * XXX this feature is currently unused, see "endian" comment below. 86 */ 87 #if defined(cray) 88 #define B64 long 89 #endif 90 #if defined(convex) 91 #define B64 long long 92 #endif 93 94 /* 95 * define "LARGEDATA" to get faster permutations, by using about 72 kilobytes 96 * of lookup tables. This speeds up des_setkey() and des_cipher(), but has 97 * little effect on crypt(). 98 */ 99 #if defined(notdef) 100 #define LARGEDATA 101 #endif 102 103 /* compile with "-DSTATIC=int" when profiling */ 104 #ifndef STATIC 105 #define STATIC static 106 #endif 107 STATIC init_des(), init_perm(), permute(); 108 #ifdef DEBUG 109 STATIC prtab(); 110 #endif 111 112 /* ==================================== */ 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 unsigned char b[8]; 230 struct { 231 int32_t i0; 232 int32_t i1; 233 } b32; 234 #if defined(B64) 235 B64 b64; 236 #endif 237 } C_block; 238 239 /* 240 * Convert twenty-four-bit long in host-order 241 * to six bits (and 2 low-order zeroes) per char little-endian format. 242 */ 243 #define TO_SIX_BIT(rslt, src) { \ 244 C_block cvt; \ 245 cvt.b[0] = src; src >>= 6; \ 246 cvt.b[1] = src; src >>= 6; \ 247 cvt.b[2] = src; src >>= 6; \ 248 cvt.b[3] = src; \ 249 rslt = (cvt.b32.i0 & 0x3f3f3f3fL) << 2; \ 250 } 251 252 /* 253 * These macros may someday permit efficient use of 64-bit integers. 254 */ 255 #define ZERO(d,d0,d1) d0 = 0, d1 = 0 256 #define LOAD(d,d0,d1,bl) d0 = (bl).b32.i0, d1 = (bl).b32.i1 257 #define LOADREG(d,d0,d1,s,s0,s1) d0 = s0, d1 = s1 258 #define OR(d,d0,d1,bl) d0 |= (bl).b32.i0, d1 |= (bl).b32.i1 259 #define STORE(s,s0,s1,bl) (bl).b32.i0 = s0, (bl).b32.i1 = s1 260 #define DCL_BLOCK(d,d0,d1) int32_t d0, d1 261 262 #if defined(LARGEDATA) 263 /* Waste memory like crazy. Also, do permutations in line */ 264 #define LGCHUNKBITS 3 265 #define CHUNKBITS (1<<LGCHUNKBITS) 266 #define PERM6464(d,d0,d1,cpp,p) \ 267 LOAD(d,d0,d1,(p)[(0<<CHUNKBITS)+(cpp)[0]]); \ 268 OR (d,d0,d1,(p)[(1<<CHUNKBITS)+(cpp)[1]]); \ 269 OR (d,d0,d1,(p)[(2<<CHUNKBITS)+(cpp)[2]]); \ 270 OR (d,d0,d1,(p)[(3<<CHUNKBITS)+(cpp)[3]]); \ 271 OR (d,d0,d1,(p)[(4<<CHUNKBITS)+(cpp)[4]]); \ 272 OR (d,d0,d1,(p)[(5<<CHUNKBITS)+(cpp)[5]]); \ 273 OR (d,d0,d1,(p)[(6<<CHUNKBITS)+(cpp)[6]]); \ 274 OR (d,d0,d1,(p)[(7<<CHUNKBITS)+(cpp)[7]]); 275 #define PERM3264(d,d0,d1,cpp,p) \ 276 LOAD(d,d0,d1,(p)[(0<<CHUNKBITS)+(cpp)[0]]); \ 277 OR (d,d0,d1,(p)[(1<<CHUNKBITS)+(cpp)[1]]); \ 278 OR (d,d0,d1,(p)[(2<<CHUNKBITS)+(cpp)[2]]); \ 279 OR (d,d0,d1,(p)[(3<<CHUNKBITS)+(cpp)[3]]); 280 #else 281 /* "small data" */ 282 #define LGCHUNKBITS 2 283 #define CHUNKBITS (1<<LGCHUNKBITS) 284 #define PERM6464(d,d0,d1,cpp,p) \ 285 { C_block tblk; permute(cpp,&tblk,p,8); LOAD (d,d0,d1,tblk); } 286 #define PERM3264(d,d0,d1,cpp,p) \ 287 { C_block tblk; permute(cpp,&tblk,p,4); LOAD (d,d0,d1,tblk); } 288 289 STATIC 290 permute(cp, out, p, chars_in) 291 unsigned char *cp; 292 C_block *out; 293 register C_block *p; 294 int chars_in; 295 { 296 register DCL_BLOCK(D,D0,D1); 297 register C_block *tp; 298 register int t; 299 300 ZERO(D,D0,D1); 301 do { 302 t = *cp++; 303 tp = &p[t&0xf]; OR(D,D0,D1,*tp); p += (1<<CHUNKBITS); 304 tp = &p[t>>4]; OR(D,D0,D1,*tp); p += (1<<CHUNKBITS); 305 } while (--chars_in > 0); 306 STORE(D,D0,D1,*out); 307 } 308 #endif /* LARGEDATA */ 309 310 311 /* ===== (mostly) Standard DES Tables ==================== */ 312 313 static unsigned char IP[] = { /* initial permutation */ 314 58, 50, 42, 34, 26, 18, 10, 2, 315 60, 52, 44, 36, 28, 20, 12, 4, 316 62, 54, 46, 38, 30, 22, 14, 6, 317 64, 56, 48, 40, 32, 24, 16, 8, 318 57, 49, 41, 33, 25, 17, 9, 1, 319 59, 51, 43, 35, 27, 19, 11, 3, 320 61, 53, 45, 37, 29, 21, 13, 5, 321 63, 55, 47, 39, 31, 23, 15, 7, 322 }; 323 324 /* The final permutation is the inverse of IP - no table is necessary */ 325 326 static unsigned char ExpandTr[] = { /* expansion operation */ 327 32, 1, 2, 3, 4, 5, 328 4, 5, 6, 7, 8, 9, 329 8, 9, 10, 11, 12, 13, 330 12, 13, 14, 15, 16, 17, 331 16, 17, 18, 19, 20, 21, 332 20, 21, 22, 23, 24, 25, 333 24, 25, 26, 27, 28, 29, 334 28, 29, 30, 31, 32, 1, 335 }; 336 337 static unsigned char PC1[] = { /* permuted choice table 1 */ 338 57, 49, 41, 33, 25, 17, 9, 339 1, 58, 50, 42, 34, 26, 18, 340 10, 2, 59, 51, 43, 35, 27, 341 19, 11, 3, 60, 52, 44, 36, 342 343 63, 55, 47, 39, 31, 23, 15, 344 7, 62, 54, 46, 38, 30, 22, 345 14, 6, 61, 53, 45, 37, 29, 346 21, 13, 5, 28, 20, 12, 4, 347 }; 348 349 static unsigned char Rotates[] = { /* PC1 rotation schedule */ 350 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1, 351 }; 352 353 /* note: each "row" of PC2 is left-padded with bits that make it invertible */ 354 static unsigned char PC2[] = { /* permuted choice table 2 */ 355 9, 18, 14, 17, 11, 24, 1, 5, 356 22, 25, 3, 28, 15, 6, 21, 10, 357 35, 38, 23, 19, 12, 4, 26, 8, 358 43, 54, 16, 7, 27, 20, 13, 2, 359 360 0, 0, 41, 52, 31, 37, 47, 55, 361 0, 0, 30, 40, 51, 45, 33, 48, 362 0, 0, 44, 49, 39, 56, 34, 53, 363 0, 0, 46, 42, 50, 36, 29, 32, 364 }; 365 366 static unsigned char S[8][64] = { /* 48->32 bit substitution tables */ 367 /* S[1] */ 368 14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7, 369 0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8, 370 4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0, 371 15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13, 372 /* S[2] */ 373 15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10, 374 3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5, 375 0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15, 376 13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9, 377 /* S[3] */ 378 10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8, 379 13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1, 380 13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7, 381 1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12, 382 /* S[4] */ 383 7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15, 384 13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9, 385 10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4, 386 3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14, 387 /* S[5] */ 388 2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9, 389 14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6, 390 4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14, 391 11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3, 392 /* S[6] */ 393 12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11, 394 10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8, 395 9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6, 396 4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13, 397 /* S[7] */ 398 4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1, 399 13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6, 400 1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2, 401 6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12, 402 /* S[8] */ 403 13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7, 404 1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2, 405 7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8, 406 2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11, 407 }; 408 409 static unsigned char P32Tr[] = { /* 32-bit permutation function */ 410 16, 7, 20, 21, 411 29, 12, 28, 17, 412 1, 15, 23, 26, 413 5, 18, 31, 10, 414 2, 8, 24, 14, 415 32, 27, 3, 9, 416 19, 13, 30, 6, 417 22, 11, 4, 25, 418 }; 419 420 static unsigned char CIFP[] = { /* compressed/interleaved permutation */ 421 1, 2, 3, 4, 17, 18, 19, 20, 422 5, 6, 7, 8, 21, 22, 23, 24, 423 9, 10, 11, 12, 25, 26, 27, 28, 424 13, 14, 15, 16, 29, 30, 31, 32, 425 426 33, 34, 35, 36, 49, 50, 51, 52, 427 37, 38, 39, 40, 53, 54, 55, 56, 428 41, 42, 43, 44, 57, 58, 59, 60, 429 45, 46, 47, 48, 61, 62, 63, 64, 430 }; 431 432 static unsigned char itoa64[] = /* 0..63 => ascii-64 */ 433 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; 434 435 436 /* ===== Tables that are initialized at run time ==================== */ 437 438 439 static unsigned char a64toi[128]; /* ascii-64 => 0..63 */ 440 441 /* Initial key schedule permutation */ 442 static C_block PC1ROT[64/CHUNKBITS][1<<CHUNKBITS]; 443 444 /* Subsequent key schedule rotation permutations */ 445 static C_block PC2ROT[2][64/CHUNKBITS][1<<CHUNKBITS]; 446 447 /* Initial permutation/expansion table */ 448 static C_block IE3264[32/CHUNKBITS][1<<CHUNKBITS]; 449 450 /* Table that combines the S, P, and E operations. */ 451 static int32_t SPE[2][8][64]; 452 453 /* compressed/interleaved => final permutation table */ 454 static C_block CF6464[64/CHUNKBITS][1<<CHUNKBITS]; 455 456 457 /* ==================================== */ 458 459 460 static C_block constdatablock; /* encryption constant */ 461 static char cryptresult[1+4+4+11+1]; /* encrypted result */ 462 463 /* 464 * Return a pointer to static data consisting of the "setting" 465 * followed by an encryption produced by the "key" and "setting". 466 */ 467 char * 468 crypt(key, setting) 469 register const char *key; 470 register const char *setting; 471 { 472 register char *encp; 473 register int32_t i; 474 register int t; 475 int32_t salt; 476 int num_iter, salt_size; 477 C_block keyblock, rsltblock; 478 479 for (i = 0; i < 8; i++) { 480 if ((t = 2*(unsigned char)(*key)) != 0) 481 key++; 482 keyblock.b[i] = t; 483 } 484 if (des_setkey((char *)keyblock.b)) /* also initializes "a64toi" */ 485 return (NULL); 486 487 encp = &cryptresult[0]; 488 switch (*setting) { 489 case _PASSWORD_EFMT1: 490 /* 491 * Involve the rest of the password 8 characters at a time. 492 */ 493 while (*key) { 494 if (des_cipher((char *)&keyblock, 495 (char *)&keyblock, 0L, 1)) 496 return (NULL); 497 for (i = 0; i < 8; i++) { 498 if ((t = 2*(unsigned char)(*key)) != 0) 499 key++; 500 keyblock.b[i] ^= t; 501 } 502 if (des_setkey((char *)keyblock.b)) 503 return (NULL); 504 } 505 506 *encp++ = *setting++; 507 508 /* get iteration count */ 509 num_iter = 0; 510 for (i = 4; --i >= 0; ) { 511 if ((t = (unsigned char)setting[i]) == '\0') 512 t = '.'; 513 encp[i] = t; 514 num_iter = (num_iter<<6) | a64toi[t]; 515 } 516 setting += 4; 517 encp += 4; 518 salt_size = 4; 519 break; 520 default: 521 num_iter = 25; 522 salt_size = 2; 523 } 524 525 salt = 0; 526 for (i = salt_size; --i >= 0; ) { 527 if ((t = (unsigned char)setting[i]) == '\0') 528 t = '.'; 529 encp[i] = t; 530 salt = (salt<<6) | a64toi[t]; 531 } 532 encp += salt_size; 533 if (des_cipher((char *)&constdatablock, (char *)&rsltblock, 534 salt, num_iter)) 535 return (NULL); 536 537 /* 538 * Encode the 64 cipher bits as 11 ascii characters. 539 */ 540 i = ((int32_t)((rsltblock.b[0]<<8) | rsltblock.b[1])<<8) | 541 rsltblock.b[2]; 542 encp[3] = itoa64[i&0x3f]; i >>= 6; 543 encp[2] = itoa64[i&0x3f]; i >>= 6; 544 encp[1] = itoa64[i&0x3f]; i >>= 6; 545 encp[0] = itoa64[i]; encp += 4; 546 i = ((int32_t)((rsltblock.b[3]<<8) | rsltblock.b[4])<<8) | 547 rsltblock.b[5]; 548 encp[3] = itoa64[i&0x3f]; i >>= 6; 549 encp[2] = itoa64[i&0x3f]; i >>= 6; 550 encp[1] = itoa64[i&0x3f]; i >>= 6; 551 encp[0] = itoa64[i]; encp += 4; 552 i = ((int32_t)((rsltblock.b[6])<<8) | rsltblock.b[7])<<2; 553 encp[2] = itoa64[i&0x3f]; i >>= 6; 554 encp[1] = itoa64[i&0x3f]; i >>= 6; 555 encp[0] = itoa64[i]; 556 557 encp[3] = 0; 558 559 return (cryptresult); 560 } 561 562 563 /* 564 * The Key Schedule, filled in by des_setkey() or setkey(). 565 */ 566 #define KS_SIZE 16 567 static C_block KS[KS_SIZE]; 568 569 /* 570 * Set up the key schedule from the key. 571 */ 572 des_setkey(key) 573 register const char *key; 574 { 575 register DCL_BLOCK(K, K0, K1); 576 register C_block *ptabp; 577 register int i; 578 static int des_ready = 0; 579 580 if (!des_ready) { 581 init_des(); 582 des_ready = 1; 583 } 584 585 PERM6464(K,K0,K1,(unsigned char *)key,(C_block *)PC1ROT); 586 key = (char *)&KS[0]; 587 STORE(K&~0x03030303L, K0&~0x03030303L, K1, *(C_block *)key); 588 for (i = 1; i < 16; i++) { 589 key += sizeof(C_block); 590 STORE(K,K0,K1,*(C_block *)key); 591 ptabp = (C_block *)PC2ROT[Rotates[i]-1]; 592 PERM6464(K,K0,K1,(unsigned char *)key,ptabp); 593 STORE(K&~0x03030303L, K0&~0x03030303L, K1, *(C_block *)key); 594 } 595 return (0); 596 } 597 598 /* 599 * Encrypt (or decrypt if num_iter < 0) the 8 chars at "in" with abs(num_iter) 600 * iterations of DES, using the the given 24-bit salt and the pre-computed key 601 * schedule, and store the resulting 8 chars at "out" (in == out is permitted). 602 * 603 * NOTE: the performance of this routine is critically dependent on your 604 * compiler and machine architecture. 605 */ 606 des_cipher(in, out, salt, num_iter) 607 const char *in; 608 char *out; 609 long salt; 610 int num_iter; 611 { 612 /* variables that we want in registers, most important first */ 613 #if defined(pdp11) 614 register int j; 615 #endif 616 register int32_t L0, L1, R0, R1, k; 617 register C_block *kp; 618 register int ks_inc, loop_count; 619 C_block B; 620 621 L0 = salt; 622 TO_SIX_BIT(salt, L0); /* convert to 4*(6+2) format */ 623 624 #if defined(vax) || defined(pdp11) 625 salt = ~salt; /* "x &~ y" is faster than "x & y". */ 626 #define SALT (~salt) 627 #else 628 #define SALT salt 629 #endif 630 631 #if defined(MUST_ALIGN) 632 B.b[0] = in[0]; B.b[1] = in[1]; B.b[2] = in[2]; B.b[3] = in[3]; 633 B.b[4] = in[4]; B.b[5] = in[5]; B.b[6] = in[6]; B.b[7] = in[7]; 634 LOAD(L,L0,L1,B); 635 #else 636 LOAD(L,L0,L1,*(C_block *)in); 637 #endif 638 LOADREG(R,R0,R1,L,L0,L1); 639 L0 &= 0x55555555L; 640 L1 &= 0x55555555L; 641 L0 = (L0 << 1) | L1; /* L0 is the even-numbered input bits */ 642 R0 &= 0xaaaaaaaaL; 643 R1 = (R1 >> 1) & 0x55555555L; 644 L1 = R0 | R1; /* L1 is the odd-numbered input bits */ 645 STORE(L,L0,L1,B); 646 PERM3264(L,L0,L1,B.b, (C_block *)IE3264); /* even bits */ 647 PERM3264(R,R0,R1,B.b+4,(C_block *)IE3264); /* odd bits */ 648 649 if (num_iter >= 0) 650 { /* encryption */ 651 kp = &KS[0]; 652 ks_inc = sizeof(*kp); 653 } 654 else 655 { /* decryption */ 656 return (1); /* always fail */ 657 } 658 659 while (--num_iter >= 0) { 660 loop_count = 8; 661 do { 662 663 #define SPTAB(t, i) \ 664 (*(int32_t *)((unsigned char *)t + i*(sizeof(int32_t)/4))) 665 #if defined(gould) 666 /* use this if B.b[i] is evaluated just once ... */ 667 #define DOXOR(x,y,i) x^=SPTAB(SPE[0][i],B.b[i]); y^=SPTAB(SPE[1][i],B.b[i]); 668 #else 669 #if defined(pdp11) 670 /* use this if your "long" int indexing is slow */ 671 #define DOXOR(x,y,i) j=B.b[i]; x^=SPTAB(SPE[0][i],j); y^=SPTAB(SPE[1][i],j); 672 #else 673 /* use this if "k" is allocated to a register ... */ 674 #define DOXOR(x,y,i) k=B.b[i]; x^=SPTAB(SPE[0][i],k); y^=SPTAB(SPE[1][i],k); 675 #endif 676 #endif 677 678 #define CRUNCH(p0, p1, q0, q1) \ 679 k = (q0 ^ q1) & SALT; \ 680 B.b32.i0 = k ^ q0 ^ kp->b32.i0; \ 681 B.b32.i1 = k ^ q1 ^ kp->b32.i1; \ 682 kp = (C_block *)((char *)kp+ks_inc); \ 683 \ 684 DOXOR(p0, p1, 0); \ 685 DOXOR(p0, p1, 1); \ 686 DOXOR(p0, p1, 2); \ 687 DOXOR(p0, p1, 3); \ 688 DOXOR(p0, p1, 4); \ 689 DOXOR(p0, p1, 5); \ 690 DOXOR(p0, p1, 6); \ 691 DOXOR(p0, p1, 7); 692 693 CRUNCH(L0, L1, R0, R1); 694 CRUNCH(R0, R1, L0, L1); 695 } while (--loop_count != 0); 696 kp = (C_block *)((char *)kp-(ks_inc*KS_SIZE)); 697 698 699 /* swap L and R */ 700 L0 ^= R0; L1 ^= R1; 701 R0 ^= L0; R1 ^= L1; 702 L0 ^= R0; L1 ^= R1; 703 } 704 705 /* store the encrypted (or decrypted) result */ 706 L0 = ((L0 >> 3) & 0x0f0f0f0fL) | ((L1 << 1) & 0xf0f0f0f0L); 707 L1 = ((R0 >> 3) & 0x0f0f0f0fL) | ((R1 << 1) & 0xf0f0f0f0L); 708 STORE(L,L0,L1,B); 709 PERM6464(L,L0,L1,B.b, (C_block *)CF6464); 710 #if defined(MUST_ALIGN) 711 STORE(L,L0,L1,B); 712 out[0] = B.b[0]; out[1] = B.b[1]; out[2] = B.b[2]; out[3] = B.b[3]; 713 out[4] = B.b[4]; out[5] = B.b[5]; out[6] = B.b[6]; out[7] = B.b[7]; 714 #else 715 STORE(L,L0,L1,*(C_block *)out); 716 #endif 717 return (0); 718 } 719 720 721 /* 722 * Initialize various tables. This need only be done once. It could even be 723 * done at compile time, if the compiler were capable of that sort of thing. 724 */ 725 STATIC 726 init_des() 727 { 728 register int i, j; 729 register int32_t k; 730 register int tableno; 731 static unsigned char perm[64], tmp32[32]; /* "static" for speed */ 732 733 /* 734 * table that converts chars "./0-9A-Za-z"to integers 0-63. 735 */ 736 for (i = 0; i < 64; i++) 737 a64toi[itoa64[i]] = i; 738 739 /* 740 * PC1ROT - bit reverse, then PC1, then Rotate, then PC2. 741 */ 742 for (i = 0; i < 64; i++) 743 perm[i] = 0; 744 for (i = 0; i < 64; i++) { 745 if ((k = PC2[i]) == 0) 746 continue; 747 k += Rotates[0]-1; 748 if ((k%28) < Rotates[0]) k -= 28; 749 k = PC1[k]; 750 if (k > 0) { 751 k--; 752 k = (k|07) - (k&07); 753 k++; 754 } 755 perm[i] = k; 756 } 757 #ifdef DEBUG 758 prtab("pc1tab", perm, 8); 759 #endif 760 init_perm(PC1ROT, perm, 8, 8); 761 762 /* 763 * PC2ROT - PC2 inverse, then Rotate (once or twice), then PC2. 764 */ 765 for (j = 0; j < 2; j++) { 766 unsigned char pc2inv[64]; 767 for (i = 0; i < 64; i++) 768 perm[i] = pc2inv[i] = 0; 769 for (i = 0; i < 64; i++) { 770 if ((k = PC2[i]) == 0) 771 continue; 772 pc2inv[k-1] = i+1; 773 } 774 for (i = 0; i < 64; i++) { 775 if ((k = PC2[i]) == 0) 776 continue; 777 k += j; 778 if ((k%28) <= j) k -= 28; 779 perm[i] = pc2inv[k]; 780 } 781 #ifdef DEBUG 782 prtab("pc2tab", perm, 8); 783 #endif 784 init_perm(PC2ROT[j], perm, 8, 8); 785 } 786 787 /* 788 * Bit reverse, then initial permutation, then expansion. 789 */ 790 for (i = 0; i < 8; i++) { 791 for (j = 0; j < 8; j++) { 792 k = (j < 2)? 0: IP[ExpandTr[i*6+j-2]-1]; 793 if (k > 32) 794 k -= 32; 795 else if (k > 0) 796 k--; 797 if (k > 0) { 798 k--; 799 k = (k|07) - (k&07); 800 k++; 801 } 802 perm[i*8+j] = k; 803 } 804 } 805 #ifdef DEBUG 806 prtab("ietab", perm, 8); 807 #endif 808 init_perm(IE3264, perm, 4, 8); 809 810 /* 811 * Compression, then final permutation, then bit reverse. 812 */ 813 for (i = 0; i < 64; i++) { 814 k = IP[CIFP[i]-1]; 815 if (k > 0) { 816 k--; 817 k = (k|07) - (k&07); 818 k++; 819 } 820 perm[k-1] = i+1; 821 } 822 #ifdef DEBUG 823 prtab("cftab", perm, 8); 824 #endif 825 init_perm(CF6464, perm, 8, 8); 826 827 /* 828 * SPE table 829 */ 830 for (i = 0; i < 48; i++) 831 perm[i] = P32Tr[ExpandTr[i]-1]; 832 for (tableno = 0; tableno < 8; tableno++) { 833 for (j = 0; j < 64; j++) { 834 k = (((j >> 0) &01) << 5)| 835 (((j >> 1) &01) << 3)| 836 (((j >> 2) &01) << 2)| 837 (((j >> 3) &01) << 1)| 838 (((j >> 4) &01) << 0)| 839 (((j >> 5) &01) << 4); 840 k = S[tableno][k]; 841 k = (((k >> 3)&01) << 0)| 842 (((k >> 2)&01) << 1)| 843 (((k >> 1)&01) << 2)| 844 (((k >> 0)&01) << 3); 845 for (i = 0; i < 32; i++) 846 tmp32[i] = 0; 847 for (i = 0; i < 4; i++) 848 tmp32[4 * tableno + i] = (k >> i) & 01; 849 k = 0; 850 for (i = 24; --i >= 0; ) 851 k = (k<<1) | tmp32[perm[i]-1]; 852 TO_SIX_BIT(SPE[0][tableno][j], k); 853 k = 0; 854 for (i = 24; --i >= 0; ) 855 k = (k<<1) | tmp32[perm[i+24]-1]; 856 TO_SIX_BIT(SPE[1][tableno][j], k); 857 } 858 } 859 } 860 861 /* 862 * Initialize "perm" to represent transformation "p", which rearranges 863 * (perhaps with expansion and/or contraction) one packed array of bits 864 * (of size "chars_in" characters) into another array (of size "chars_out" 865 * characters). 866 * 867 * "perm" must be all-zeroes on entry to this routine. 868 */ 869 STATIC 870 init_perm(perm, p, chars_in, chars_out) 871 C_block perm[64/CHUNKBITS][1<<CHUNKBITS]; 872 unsigned char p[64]; 873 int chars_in, chars_out; 874 { 875 register int i, j, k, l; 876 877 for (k = 0; k < chars_out*8; k++) { /* each output bit position */ 878 l = p[k] - 1; /* where this bit comes from */ 879 if (l < 0) 880 continue; /* output bit is always 0 */ 881 i = l>>LGCHUNKBITS; /* which chunk this bit comes from */ 882 l = 1<<(l&(CHUNKBITS-1)); /* mask for this bit */ 883 for (j = 0; j < (1<<CHUNKBITS); j++) { /* each chunk value */ 884 if ((j & l) != 0) 885 perm[i][j].b[k>>3] |= 1<<(k&07); 886 } 887 } 888 } 889 890 /* 891 * "setkey" routine (for backwards compatibility) 892 */ 893 setkey(key) 894 register const char *key; 895 { 896 register int i, j, k; 897 C_block keyblock; 898 899 for (i = 0; i < 8; i++) { 900 k = 0; 901 for (j = 0; j < 8; j++) { 902 k <<= 1; 903 k |= (unsigned char)*key++; 904 } 905 keyblock.b[i] = k; 906 } 907 return (des_setkey((char *)keyblock.b)); 908 } 909 910 /* 911 * "encrypt" routine (for backwards compatibility) 912 */ 913 encrypt(block, flag) 914 register char *block; 915 int flag; 916 { 917 register int i, j, k; 918 C_block cblock; 919 920 for (i = 0; i < 8; i++) { 921 k = 0; 922 for (j = 0; j < 8; j++) { 923 k <<= 1; 924 k |= (unsigned char)*block++; 925 } 926 cblock.b[i] = k; 927 } 928 if (des_cipher((char *)&cblock, (char *)&cblock, 0L, (flag ? -1: 1))) 929 return (1); 930 for (i = 7; i >= 0; i--) { 931 k = cblock.b[i]; 932 for (j = 7; j >= 0; j--) { 933 *--block = k&01; 934 k >>= 1; 935 } 936 } 937 return (0); 938 } 939 940 #ifdef DEBUG 941 STATIC 942 prtab(s, t, num_rows) 943 char *s; 944 unsigned char *t; 945 int num_rows; 946 { 947 register int i, j; 948 949 (void)printf("%s:\n", s); 950 for (i = 0; i < num_rows; i++) { 951 for (j = 0; j < 8; j++) { 952 (void)printf("%3d", t[i*8+j]); 953 } 954 (void)printf("\n"); 955 } 956 (void)printf("\n"); 957 } 958 #endif 959