1/* $NetBSD: crypt.c,v 1.32 2011/12/27 23:34:13 christos 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. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35#include <sys/cdefs.h> 36#if !defined(lint) 37#if 0 38static char sccsid[] = "@(#)crypt.c 8.1.1.1 (Berkeley) 8/18/93"; 39#else 40__RCSID("$NetBSD: crypt.c,v 1.32 2011/12/27 23:34:13 christos Exp $"); 41#endif 42#endif /* not lint */ 43 44#include <limits.h> 45#include <pwd.h> 46#include <stdlib.h> 47#include <unistd.h> 48#if defined(DEBUG) || defined(MAIN) || defined(UNIT_TEST) 49#include <stdio.h> 50#endif 51 52#include "crypt.h" 53 54/* 55 * UNIX password, and DES, encryption. 56 * By Tom Truscott, trt@rti.rti.org, 57 * from algorithms by Robert W. Baldwin and James Gillogly. 58 * 59 * References: 60 * "Mathematical Cryptology for Computer Scientists and Mathematicians," 61 * by Wayne Patterson, 1987, ISBN 0-8476-7438-X. 62 * 63 * "Password Security: A Case History," R. Morris and Ken Thompson, 64 * Communications of the ACM, vol. 22, pp. 594-597, Nov. 1979. 65 * 66 * "DES will be Totally Insecure within Ten Years," M.E. Hellman, 67 * IEEE Spectrum, vol. 16, pp. 32-39, July 1979. 68 */ 69 70/* ===== Configuration ==================== */ 71 72/* 73 * define "MUST_ALIGN" if your compiler cannot load/store 74 * long integers at arbitrary (e.g. odd) memory locations. 75 * (Either that or never pass unaligned addresses to des_cipher!) 76 */ 77#if !defined(__vax__) && !defined(__i386__) 78#define MUST_ALIGN 79#endif 80 81#ifdef CHAR_BITS 82#if CHAR_BITS != 8 83 #error C_block structure assumes 8 bit characters 84#endif 85#endif 86 87/* 88 * define "B64" to be the declaration for a 64 bit integer. 89 * XXX this feature is currently unused, see "endian" comment below. 90 */ 91#if defined(cray) 92#define B64 long 93#endif 94#if defined(convex) 95#define B64 long long 96#endif 97 98/* 99 * define "LARGEDATA" to get faster permutations, by using about 72 kilobytes 100 * of lookup tables. This speeds up des_setkey() and des_cipher(), but has 101 * little effect on crypt(). 102 */ 103#if defined(notdef) 104#define LARGEDATA 105#endif 106 107/* compile with "-DSTATIC=void" when profiling */ 108#ifndef STATIC 109#define STATIC static void 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 228typedef 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#endif /* LARGEDATA */ 289 290STATIC init_des(void); 291STATIC init_perm(C_block [64/CHUNKBITS][1<<CHUNKBITS], 292 const unsigned char [64], int, int); 293#ifndef LARGEDATA 294STATIC permute(const unsigned char *, C_block *, C_block *, int); 295#endif 296#ifdef DEBUG 297STATIC prtab(const char *, unsigned char *, int); 298#endif 299 300 301#ifndef LARGEDATA 302STATIC 303permute(const unsigned char *cp, C_block *out, C_block *p, int chars_in) 304{ 305 DCL_BLOCK(D,D0,D1); 306 C_block *tp; 307 int t; 308 309 ZERO(D,D0,D1); 310 do { 311 t = *cp++; 312 tp = &p[t&0xf]; OR(D,D0,D1,*tp); p += (1<<CHUNKBITS); 313 tp = &p[t>>4]; OR(D,D0,D1,*tp); p += (1<<CHUNKBITS); 314 } while (--chars_in > 0); 315 STORE(D,D0,D1,*out); 316} 317#endif /* LARGEDATA */ 318 319 320/* ===== (mostly) Standard DES Tables ==================== */ 321 322static const unsigned char IP[] = { /* initial permutation */ 323 58, 50, 42, 34, 26, 18, 10, 2, 324 60, 52, 44, 36, 28, 20, 12, 4, 325 62, 54, 46, 38, 30, 22, 14, 6, 326 64, 56, 48, 40, 32, 24, 16, 8, 327 57, 49, 41, 33, 25, 17, 9, 1, 328 59, 51, 43, 35, 27, 19, 11, 3, 329 61, 53, 45, 37, 29, 21, 13, 5, 330 63, 55, 47, 39, 31, 23, 15, 7, 331}; 332 333/* The final permutation is the inverse of IP - no table is necessary */ 334 335static const unsigned char ExpandTr[] = { /* expansion operation */ 336 32, 1, 2, 3, 4, 5, 337 4, 5, 6, 7, 8, 9, 338 8, 9, 10, 11, 12, 13, 339 12, 13, 14, 15, 16, 17, 340 16, 17, 18, 19, 20, 21, 341 20, 21, 22, 23, 24, 25, 342 24, 25, 26, 27, 28, 29, 343 28, 29, 30, 31, 32, 1, 344}; 345 346static const unsigned char PC1[] = { /* permuted choice table 1 */ 347 57, 49, 41, 33, 25, 17, 9, 348 1, 58, 50, 42, 34, 26, 18, 349 10, 2, 59, 51, 43, 35, 27, 350 19, 11, 3, 60, 52, 44, 36, 351 352 63, 55, 47, 39, 31, 23, 15, 353 7, 62, 54, 46, 38, 30, 22, 354 14, 6, 61, 53, 45, 37, 29, 355 21, 13, 5, 28, 20, 12, 4, 356}; 357 358static const unsigned char Rotates[] = {/* PC1 rotation schedule */ 359 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1, 360}; 361 362/* note: each "row" of PC2 is left-padded with bits that make it invertible */ 363static const unsigned char PC2[] = { /* permuted choice table 2 */ 364 9, 18, 14, 17, 11, 24, 1, 5, 365 22, 25, 3, 28, 15, 6, 21, 10, 366 35, 38, 23, 19, 12, 4, 26, 8, 367 43, 54, 16, 7, 27, 20, 13, 2, 368 369 0, 0, 41, 52, 31, 37, 47, 55, 370 0, 0, 30, 40, 51, 45, 33, 48, 371 0, 0, 44, 49, 39, 56, 34, 53, 372 0, 0, 46, 42, 50, 36, 29, 32, 373}; 374 375static const unsigned char S[8][64] = { /* 48->32 bit substitution tables */ 376 /* S[1] */ 377 { 14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7, 378 0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8, 379 4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0, 380 15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13 }, 381 /* S[2] */ 382 { 15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10, 383 3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5, 384 0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15, 385 13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9 }, 386 /* S[3] */ 387 { 10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8, 388 13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1, 389 13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7, 390 1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12 }, 391 /* S[4] */ 392 { 7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15, 393 13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9, 394 10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4, 395 3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14 }, 396 /* S[5] */ 397 { 2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9, 398 14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6, 399 4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14, 400 11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3 }, 401 /* S[6] */ 402 { 12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11, 403 10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8, 404 9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6, 405 4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13 }, 406 /* S[7] */ 407 { 4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1, 408 13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6, 409 1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2, 410 6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12 }, 411 /* S[8] */ 412 { 13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7, 413 1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2, 414 7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8, 415 2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11 } 416}; 417 418static const unsigned char P32Tr[] = { /* 32-bit permutation function */ 419 16, 7, 20, 21, 420 29, 12, 28, 17, 421 1, 15, 23, 26, 422 5, 18, 31, 10, 423 2, 8, 24, 14, 424 32, 27, 3, 9, 425 19, 13, 30, 6, 426 22, 11, 4, 25, 427}; 428 429static const unsigned char CIFP[] = { /* compressed/interleaved permutation */ 430 1, 2, 3, 4, 17, 18, 19, 20, 431 5, 6, 7, 8, 21, 22, 23, 24, 432 9, 10, 11, 12, 25, 26, 27, 28, 433 13, 14, 15, 16, 29, 30, 31, 32, 434 435 33, 34, 35, 36, 49, 50, 51, 52, 436 37, 38, 39, 40, 53, 54, 55, 56, 437 41, 42, 43, 44, 57, 58, 59, 60, 438 45, 46, 47, 48, 61, 62, 63, 64, 439}; 440 441static const unsigned char itoa64[] = /* 0..63 => ascii-64 */ 442 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; 443 444 445/* ===== Tables that are initialized at run time ==================== */ 446 447 448/* Initial key schedule permutation */ 449static C_block PC1ROT[64/CHUNKBITS][1<<CHUNKBITS]; 450 451/* Subsequent key schedule rotation permutations */ 452static C_block PC2ROT[2][64/CHUNKBITS][1<<CHUNKBITS]; 453 454/* Initial permutation/expansion table */ 455static C_block IE3264[32/CHUNKBITS][1<<CHUNKBITS]; 456 457/* Table that combines the S, P, and E operations. */ 458static int32_t SPE[2][8][64]; 459 460/* compressed/interleaved => final permutation table */ 461static C_block CF6464[64/CHUNKBITS][1<<CHUNKBITS]; 462 463 464/* ==================================== */ 465 466 467static C_block constdatablock; /* encryption constant */ 468static char cryptresult[1+4+4+11+1]; /* encrypted result */ 469 470/* 471 * We match the behavior of UFC-crypt on systems where "char" is signed by 472 * default (the majority), regardless of char's signedness on our system. 473 */ 474static inline int 475ascii_to_bin(char ch) 476{ 477 signed char sch = ch; 478 int retval; 479 480 if (sch >= 'a') 481 retval = sch - ('a' - 38); 482 else if (sch >= 'A') 483 retval = sch - ('A' - 12); 484 else 485 retval = sch - '.'; 486 487 return retval & 0x3f; 488} 489 490/* 491 * When we choose to "support" invalid salts, nevertheless disallow those 492 * containing characters that would violate the passwd file format. 493 */ 494static inline int 495ascii_is_unsafe(char ch) 496{ 497 return !ch || ch == '\n' || ch == ':'; 498} 499 500/* 501 * Return a pointer to static data consisting of the "setting" 502 * followed by an encryption produced by the "key" and "setting". 503 */ 504static char * 505__crypt(const char *key, const char *setting) 506{ 507 char *encp; 508 int32_t i; 509 int t; 510 int32_t salt; 511 int num_iter, salt_size; 512 C_block keyblock, rsltblock; 513 514 /* Non-DES encryption schemes hook in here. */ 515 if (setting[0] == _PASSWORD_NONDES) { 516 switch (setting[1]) { 517 case '2': 518 return (__bcrypt(key, setting)); 519 case 's': 520 return (__crypt_sha1(key, setting)); 521 case '1': 522 default: 523 return (__md5crypt(key, setting)); 524 } 525 } 526 527 for (i = 0; i < 8; i++) { 528 if ((t = 2*(unsigned char)(*key)) != 0) 529 key++; 530 keyblock.b[i] = t; 531 } 532 if (des_setkey((char *)keyblock.b)) 533 return (NULL); 534 535 encp = &cryptresult[0]; 536 switch (*setting) { 537 case _PASSWORD_EFMT1: 538 /* 539 * Involve the rest of the password 8 characters at a time. 540 */ 541 while (*key) { 542 if (des_cipher((char *)(void *)&keyblock, 543 (char *)(void *)&keyblock, 0L, 1)) 544 return (NULL); 545 for (i = 0; i < 8; i++) { 546 if ((t = 2*(unsigned char)(*key)) != 0) 547 key++; 548 keyblock.b[i] ^= t; 549 } 550 if (des_setkey((char *)keyblock.b)) 551 return (NULL); 552 } 553 554 *encp++ = *setting++; 555 556 /* get iteration count */ 557 num_iter = 0; 558 for (i = 4; --i >= 0; ) { 559 int value = ascii_to_bin(setting[i]); 560 if (itoa64[value] != setting[i]) 561 return NULL; 562 encp[i] = setting[i]; 563 num_iter = (num_iter << 6) | value; 564 } 565 if (num_iter == 0) 566 return NULL; 567 setting += 4; 568 encp += 4; 569 salt_size = 4; 570 break; 571 default: 572 num_iter = 25; 573 salt_size = 2; 574 if (ascii_is_unsafe(setting[0]) || ascii_is_unsafe(setting[1])) 575 return NULL; 576 } 577 578 salt = 0; 579 for (i = salt_size; --i >= 0; ) { 580 int value = ascii_to_bin(setting[i]); 581 if (salt_size > 2 && itoa64[value] != setting[i]) 582 return NULL; 583 encp[i] = setting[i]; 584 salt = (salt << 6) | value; 585 } 586 encp += salt_size; 587 if (des_cipher((char *)(void *)&constdatablock, 588 (char *)(void *)&rsltblock, salt, num_iter)) 589 return (NULL); 590 591 /* 592 * Encode the 64 cipher bits as 11 ascii characters. 593 */ 594 i = ((int32_t)((rsltblock.b[0]<<8) | rsltblock.b[1])<<8) | 595 rsltblock.b[2]; 596 encp[3] = itoa64[i&0x3f]; i >>= 6; 597 encp[2] = itoa64[i&0x3f]; i >>= 6; 598 encp[1] = itoa64[i&0x3f]; i >>= 6; 599 encp[0] = itoa64[i]; encp += 4; 600 i = ((int32_t)((rsltblock.b[3]<<8) | rsltblock.b[4])<<8) | 601 rsltblock.b[5]; 602 encp[3] = itoa64[i&0x3f]; i >>= 6; 603 encp[2] = itoa64[i&0x3f]; i >>= 6; 604 encp[1] = itoa64[i&0x3f]; i >>= 6; 605 encp[0] = itoa64[i]; encp += 4; 606 i = ((int32_t)((rsltblock.b[6])<<8) | rsltblock.b[7])<<2; 607 encp[2] = itoa64[i&0x3f]; i >>= 6; 608 encp[1] = itoa64[i&0x3f]; i >>= 6; 609 encp[0] = itoa64[i]; 610 611 encp[3] = 0; 612 613 return (cryptresult); 614} 615 616char * 617crypt(const char *key, const char *salt) 618{ 619 char *res = __crypt(key, salt); 620 if (res) 621 return res; 622 /* How do I handle errors ? Return "*0" or "*1" */ 623 return __UNCONST(salt[0] == '*' && salt[1] == '0' ? "*1" : "*0"); 624} 625 626/* 627 * The Key Schedule, filled in by 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 */ 635int 636des_setkey(const char *key) 637{ 638 DCL_BLOCK(K, K0, K1); 639 C_block *help, *ptabp; 640 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,(const unsigned char *)key,(C_block *)PC1ROT); 649 help = &KS[0]; 650 STORE(K&~0x03030303L, K0&~0x03030303L, K1, *help); 651 for (i = 1; i < 16; i++) { 652 help++; 653 STORE(K,K0,K1,*help); 654 ptabp = (C_block *)PC2ROT[Rotates[i]-1]; 655 PERM6464(K,K0,K1,(const unsigned char *)help,ptabp); 656 STORE(K&~0x03030303L, K0&~0x03030303L, K1, *help); 657 } 658 return (0); 659} 660 661/* 662 * Encrypt (or decrypt if num_iter < 0) the 8 chars at "in" with abs(num_iter) 663 * iterations of DES, using the given 24-bit salt and the pre-computed key 664 * schedule, and store the resulting 8 chars at "out" (in == out is permitted). 665 * 666 * NOTE: the performance of this routine is critically dependent on your 667 * compiler and machine architecture. 668 */ 669int 670des_cipher(const char *in, char *out, long salt, 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, L1, R0, R1, k; 677 C_block *kp; 678 int ks_inc, loop_count; 679 C_block B; 680 681 L0 = salt; 682 TO_SIX_BIT(salt, L0); /* convert to 4*(6+2) format */ 683 684#if defined(__vax__) || defined(pdp11) 685 salt = ~salt; /* "x &~ y" is faster than "x & y". */ 686#define SALT (~salt) 687#else 688#define SALT salt 689#endif 690 691#if defined(MUST_ALIGN) 692 B.b[0] = in[0]; B.b[1] = in[1]; B.b[2] = in[2]; B.b[3] = in[3]; 693 B.b[4] = in[4]; B.b[5] = in[5]; B.b[6] = in[6]; B.b[7] = in[7]; 694 LOAD(L,L0,L1,B); 695#else 696 LOAD(L,L0,L1,*(const C_block *)in); 697#endif 698 LOADREG(R,R0,R1,L,L0,L1); 699 L0 &= 0x55555555L; 700 L1 &= 0x55555555L; 701 L0 = (L0 << 1) | L1; /* L0 is the even-numbered input bits */ 702 R0 &= 0xaaaaaaaaL; 703 R1 = (R1 >> 1) & 0x55555555L; 704 L1 = R0 | R1; /* L1 is the odd-numbered input bits */ 705 STORE(L,L0,L1,B); 706 PERM3264(L,L0,L1,B.b, (C_block *)IE3264); /* even bits */ 707 PERM3264(R,R0,R1,B.b+4,(C_block *)IE3264); /* odd bits */ 708 709 if (num_iter >= 0) 710 { /* encryption */ 711 kp = &KS[0]; 712 ks_inc = sizeof(*kp); 713 } 714 else 715 { /* decryption */ 716 num_iter = -num_iter; 717 kp = &KS[KS_SIZE-1]; 718 ks_inc = -(long)sizeof(*kp); 719 } 720 721 while (--num_iter >= 0) { 722 loop_count = 8; 723 do { 724 725#define SPTAB(t, i) \ 726 (*(int32_t *)((unsigned char *)t + i*(sizeof(int32_t)/4))) 727#if defined(gould) 728 /* use this if B.b[i] is evaluated just once ... */ 729#define DOXOR(x,y,i) x^=SPTAB(SPE[0][i],B.b[i]); y^=SPTAB(SPE[1][i],B.b[i]); 730#else 731#if defined(pdp11) 732 /* use this if your "long" int indexing is slow */ 733#define DOXOR(x,y,i) j=B.b[i]; x^=SPTAB(SPE[0][i],j); y^=SPTAB(SPE[1][i],j); 734#else 735 /* use this if "k" is allocated to a register ... */ 736#define DOXOR(x,y,i) k=B.b[i]; x^=SPTAB(SPE[0][i],k); y^=SPTAB(SPE[1][i],k); 737#endif 738#endif 739 740#define CRUNCH(p0, p1, q0, q1) \ 741 k = (q0 ^ q1) & SALT; \ 742 B.b32.i0 = k ^ q0 ^ kp->b32.i0; \ 743 B.b32.i1 = k ^ q1 ^ kp->b32.i1; \ 744 kp = (C_block *)((char *)kp+ks_inc); \ 745 \ 746 DOXOR(p0, p1, 0); \ 747 DOXOR(p0, p1, 1); \ 748 DOXOR(p0, p1, 2); \ 749 DOXOR(p0, p1, 3); \ 750 DOXOR(p0, p1, 4); \ 751 DOXOR(p0, p1, 5); \ 752 DOXOR(p0, p1, 6); \ 753 DOXOR(p0, p1, 7); 754 755 CRUNCH(L0, L1, R0, R1); 756 CRUNCH(R0, R1, L0, L1); 757 } while (--loop_count != 0); 758 kp = (C_block *)((char *)kp-(ks_inc*KS_SIZE)); 759 760 761 /* swap L and R */ 762 L0 ^= R0; L1 ^= R1; 763 R0 ^= L0; R1 ^= L1; 764 L0 ^= R0; L1 ^= R1; 765 } 766 767 /* store the encrypted (or decrypted) result */ 768 L0 = ((L0 >> 3) & 0x0f0f0f0fL) | ((L1 << 1) & 0xf0f0f0f0L); 769 L1 = ((R0 >> 3) & 0x0f0f0f0fL) | ((R1 << 1) & 0xf0f0f0f0L); 770 STORE(L,L0,L1,B); 771 PERM6464(L,L0,L1,B.b, (C_block *)CF6464); 772#if defined(MUST_ALIGN) 773 STORE(L,L0,L1,B); 774 out[0] = B.b[0]; out[1] = B.b[1]; out[2] = B.b[2]; out[3] = B.b[3]; 775 out[4] = B.b[4]; out[5] = B.b[5]; out[6] = B.b[6]; out[7] = B.b[7]; 776#else 777 STORE(L,L0,L1,*(C_block *)out); 778#endif 779 return (0); 780} 781 782 783/* 784 * Initialize various tables. This need only be done once. It could even be 785 * done at compile time, if the compiler were capable of that sort of thing. 786 */ 787STATIC 788init_des(void) 789{ 790 int i, j; 791 int32_t k; 792 int tableno; 793 static unsigned char perm[64], tmp32[32]; /* "static" for speed */ 794 795 /* 796 * PC1ROT - bit reverse, then PC1, then Rotate, then PC2. 797 */ 798 for (i = 0; i < 64; i++) 799 perm[i] = 0; 800 for (i = 0; i < 64; i++) { 801 if ((k = PC2[i]) == 0) 802 continue; 803 k += Rotates[0]-1; 804 if ((k%28) < Rotates[0]) k -= 28; 805 k = PC1[k]; 806 if (k > 0) { 807 k--; 808 k = (k|07) - (k&07); 809 k++; 810 } 811 perm[i] = k; 812 } 813#ifdef DEBUG 814 prtab("pc1tab", perm, 8); 815#endif 816 init_perm(PC1ROT, perm, 8, 8); 817 818 /* 819 * PC2ROT - PC2 inverse, then Rotate (once or twice), then PC2. 820 */ 821 for (j = 0; j < 2; j++) { 822 unsigned char pc2inv[64]; 823 for (i = 0; i < 64; i++) 824 perm[i] = pc2inv[i] = 0; 825 for (i = 0; i < 64; i++) { 826 if ((k = PC2[i]) == 0) 827 continue; 828 pc2inv[k-1] = i+1; 829 } 830 for (i = 0; i < 64; i++) { 831 if ((k = PC2[i]) == 0) 832 continue; 833 k += j; 834 if ((k%28) <= j) k -= 28; 835 perm[i] = pc2inv[k]; 836 } 837#ifdef DEBUG 838 prtab("pc2tab", perm, 8); 839#endif 840 init_perm(PC2ROT[j], perm, 8, 8); 841 } 842 843 /* 844 * Bit reverse, then initial permutation, then expansion. 845 */ 846 for (i = 0; i < 8; i++) { 847 for (j = 0; j < 8; j++) { 848 k = (j < 2)? 0: IP[ExpandTr[i*6+j-2]-1]; 849 if (k > 32) 850 k -= 32; 851 else if (k > 0) 852 k--; 853 if (k > 0) { 854 k--; 855 k = (k|07) - (k&07); 856 k++; 857 } 858 perm[i*8+j] = k; 859 } 860 } 861#ifdef DEBUG 862 prtab("ietab", perm, 8); 863#endif 864 init_perm(IE3264, perm, 4, 8); 865 866 /* 867 * Compression, then final permutation, then bit reverse. 868 */ 869 for (i = 0; i < 64; i++) { 870 k = IP[CIFP[i]-1]; 871 if (k > 0) { 872 k--; 873 k = (k|07) - (k&07); 874 k++; 875 } 876 perm[k-1] = i+1; 877 } 878#ifdef DEBUG 879 prtab("cftab", perm, 8); 880#endif 881 init_perm(CF6464, perm, 8, 8); 882 883 /* 884 * SPE table 885 */ 886 for (i = 0; i < 48; i++) 887 perm[i] = P32Tr[ExpandTr[i]-1]; 888 for (tableno = 0; tableno < 8; tableno++) { 889 for (j = 0; j < 64; j++) { 890 k = (((j >> 0) &01) << 5)| 891 (((j >> 1) &01) << 3)| 892 (((j >> 2) &01) << 2)| 893 (((j >> 3) &01) << 1)| 894 (((j >> 4) &01) << 0)| 895 (((j >> 5) &01) << 4); 896 k = S[tableno][k]; 897 k = (((k >> 3)&01) << 0)| 898 (((k >> 2)&01) << 1)| 899 (((k >> 1)&01) << 2)| 900 (((k >> 0)&01) << 3); 901 for (i = 0; i < 32; i++) 902 tmp32[i] = 0; 903 for (i = 0; i < 4; i++) 904 tmp32[4 * tableno + i] = (k >> i) & 01; 905 k = 0; 906 for (i = 24; --i >= 0; ) 907 k = (k<<1) | tmp32[perm[i]-1]; 908 TO_SIX_BIT(SPE[0][tableno][j], k); 909 k = 0; 910 for (i = 24; --i >= 0; ) 911 k = (k<<1) | tmp32[perm[i+24]-1]; 912 TO_SIX_BIT(SPE[1][tableno][j], k); 913 } 914 } 915} 916 917/* 918 * Initialize "perm" to represent transformation "p", which rearranges 919 * (perhaps with expansion and/or contraction) one packed array of bits 920 * (of size "chars_in" characters) into another array (of size "chars_out" 921 * characters). 922 * 923 * "perm" must be all-zeroes on entry to this routine. 924 */ 925STATIC 926init_perm(C_block perm[64/CHUNKBITS][1<<CHUNKBITS], const unsigned char p[64], 927 int chars_in, int chars_out) 928{ 929 int i, j, k, l; 930 931 for (k = 0; k < chars_out*8; k++) { /* each output bit position */ 932 l = p[k] - 1; /* where this bit comes from */ 933 if (l < 0) 934 continue; /* output bit is always 0 */ 935 i = l>>LGCHUNKBITS; /* which chunk this bit comes from */ 936 l = 1<<(l&(CHUNKBITS-1)); /* mask for this bit */ 937 for (j = 0; j < (1<<CHUNKBITS); j++) { /* each chunk value */ 938 if ((j & l) != 0) 939 perm[i][j].b[k>>3] |= 1<<(k&07); 940 } 941 } 942} 943 944/* 945 * "setkey" routine (for backwards compatibility) 946 */ 947int 948setkey(const char *key) 949{ 950 int i, j, k; 951 C_block keyblock; 952 953 for (i = 0; i < 8; i++) { 954 k = 0; 955 for (j = 0; j < 8; j++) { 956 k <<= 1; 957 k |= (unsigned char)*key++; 958 } 959 keyblock.b[i] = k; 960 } 961 return (des_setkey((char *)keyblock.b)); 962} 963 964/* 965 * "encrypt" routine (for backwards compatibility) 966 */ 967int 968encrypt(char *block, int flag) 969{ 970 int i, j, k; 971 C_block cblock; 972 973 for (i = 0; i < 8; i++) { 974 k = 0; 975 for (j = 0; j < 8; j++) { 976 k <<= 1; 977 k |= (unsigned char)*block++; 978 } 979 cblock.b[i] = k; 980 } 981 if (des_cipher((char *)&cblock, (char *)&cblock, 0L, (flag ? -1: 1))) 982 return (1); 983 for (i = 7; i >= 0; i--) { 984 k = cblock.b[i]; 985 for (j = 7; j >= 0; j--) { 986 *--block = k&01; 987 k >>= 1; 988 } 989 } 990 return (0); 991} 992 993#ifdef DEBUG 994STATIC 995prtab(const char *s, unsigned char *t, int num_rows) 996{ 997 int i, j; 998 999 (void)printf("%s:\n", s); 1000 for (i = 0; i < num_rows; i++) { 1001 for (j = 0; j < 8; j++) { 1002 (void)printf("%3d", t[i*8+j]); 1003 } 1004 (void)printf("\n"); 1005 } 1006 (void)printf("\n"); 1007} 1008#endif 1009 1010#if defined(MAIN) || defined(UNIT_TEST) 1011#include <err.h> 1012 1013int 1014main(int argc, char *argv[]) 1015{ 1016 if (argc < 2) 1017 errx(1, "Usage: %s password [salt]\n", argv[0]); 1018 1019 printf("%s\n", crypt(argv[1], (argc > 2) ? argv[2] : argv[1])); 1020 exit(0); 1021} 1022#endif 1023