/* * Copyright (c) 1989, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Tom Truscott. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #if defined(LIBC_SCCS) && !defined(lint) static char sccsid[] = "@(#)crypt.c 8.1 (Berkeley) 6/4/93"; #endif /* LIBC_SCCS and not lint */ #ifdef HAVE_UNISTD_H #include <unistd.h> #endif #include <limits.h> #ifdef HAVE_PWD_H #include <pwd.h> #endif #include <stdio.h> #ifndef _PASSWORD_EFMT1 #define _PASSWORD_EFMT1 '_' #endif /* * UNIX password, and DES, encryption. * By Tom Truscott, trt@rti.rti.org, * from algorithms by Robert W. Baldwin and James Gillogly. * * References: * "Mathematical Cryptology for Computer Scientists and Mathematicians," * by Wayne Patterson, 1987, ISBN 0-8476-7438-X. * * "Password Security: A Case History," R. Morris and Ken Thompson, * Communications of the ACM, vol. 22, pp. 594-597, Nov. 1979. * * "DES will be Totally Insecure within Ten Years," M.E. Hellman, * IEEE Spectrum, vol. 16, pp. 32-39, July 1979. */ /* ===== Configuration ==================== */ /* * define "MUST_ALIGN" if your compiler cannot load/store * long integers at arbitrary (e.g. odd) memory locations. * (Either that or never pass unaligned addresses to des_cipher!) */ #if !defined(vax) #define MUST_ALIGN #endif #ifdef CHAR_BITS #if CHAR_BITS != 8 #error C_block structure assumes 8 bit characters #endif #endif /* * define "LONG_IS_32_BITS" only if sizeof(long)==4. * This avoids use of bit fields (your compiler may be sloppy with them). */ #if !defined(cray) #define LONG_IS_32_BITS #endif /* * define "B64" to be the declaration for a 64 bit integer. * XXX this feature is currently unused, see "endian" comment below. */ #if defined(cray) #define B64 long #endif #if defined(convex) #define B64 long long #endif /* * define "LARGEDATA" to get faster permutations, by using about 72 kilobytes * of lookup tables. This speeds up des_setkey() and des_cipher(), but has * little effect on crypt(). */ #if defined(notdef) #define LARGEDATA #endif int des_setkey(), des_cipher(); /* compile with "-DSTATIC=int" when profiling */ #ifndef STATIC #define STATIC static #endif STATIC void init_des(), init_perm(), permute(); #ifdef DEBUG STATIC void prtab(); #endif /* ==================================== */ /* * Cipher-block representation (Bob Baldwin): * * DES operates on groups of 64 bits, numbered 1..64 (sigh). One * representation is to store one bit per byte in an array of bytes. Bit N of * the NBS spec is stored as the LSB of the Nth byte (index N-1) in the array. * Another representation stores the 64 bits in 8 bytes, with bits 1..8 in the * first byte, 9..16 in the second, and so on. The DES spec apparently has * bit 1 in the MSB of the first byte, but that is particularly noxious so we * bit-reverse each byte so that bit 1 is the LSB of the first byte, bit 8 is * the MSB of the first byte. Specifically, the 64-bit input data and key are * converted to LSB format, and the output 64-bit block is converted back into * MSB format. * * DES operates internally on groups of 32 bits which are expanded to 48 bits * by permutation E and shrunk back to 32 bits by the S boxes. To speed up * the computation, the expansion is applied only once, the expanded * representation is maintained during the encryption, and a compression * permutation is applied only at the end. To speed up the S-box lookups, * the 48 bits are maintained as eight 6 bit groups, one per byte, which * directly feed the eight S-boxes. Within each byte, the 6 bits are the * most significant ones. The low two bits of each byte are zero. (Thus, * bit 1 of the 48 bit E expansion is stored as the "4"-valued bit of the * first byte in the eight byte representation, bit 2 of the 48 bit value is * the "8"-valued bit, and so on.) In fact, a combined "SPE"-box lookup is * used, in which the output is the 64 bit result of an S-box lookup which * has been permuted by P and expanded by E, and is ready for use in the next * iteration. Two 32-bit wide tables, SPE[0] and SPE[1], are used for this * lookup. Since each byte in the 48 bit path is a multiple of four, indexed * lookup of SPE[0] and SPE[1] is simple and fast. The key schedule and * "salt" are also converted to this 8*(6+2) format. The SPE table size is * 8*64*8 = 4K bytes. * * To speed up bit-parallel operations (such as XOR), the 8 byte * representation is "union"ed with 32 bit values "i0" and "i1", and, on * machines which support it, a 64 bit value "b64". This data structure, * "C_block", has two problems. First, alignment restrictions must be * honored. Second, the byte-order (e.g. little-endian or big-endian) of * the architecture becomes visible. * * The byte-order problem is unfortunate, since on the one hand it is good * to have a machine-independent C_block representation (bits 1..8 in the * first byte, etc.), and on the other hand it is good for the LSB of the * first byte to be the LSB of i0. We cannot have both these things, so we * currently use the "little-endian" representation and avoid any multi-byte * operations that depend on byte order. This largely precludes use of the * 64-bit datatype since the relative order of i0 and i1 are unknown. It * also inhibits grouping the SPE table to look up 12 bits at a time. (The * 12 bits can be stored in a 16-bit field with 3 low-order zeroes and 1 * high-order zero, providing fast indexing into a 64-bit wide SPE.) On the * other hand, 64-bit datatypes are currently rare, and a 12-bit SPE lookup * requires a 128 kilobyte table, so perhaps this is not a big loss. * * Permutation representation (Jim Gillogly): * * A transformation is defined by its effect on each of the 8 bytes of the * 64-bit input. For each byte we give a 64-bit output that has the bits in * the input distributed appropriately. The transformation is then the OR * of the 8 sets of 64-bits. This uses 8*256*8 = 16K bytes of storage for * each transformation. Unless LARGEDATA is defined, however, a more compact * table is used which looks up 16 4-bit "chunks" rather than 8 8-bit chunks. * The smaller table uses 16*16*8 = 2K bytes for each transformation. This * is slower but tolerable, particularly for password encryption in which * the SPE transformation is iterated many times. The small tables total 9K * bytes, the large tables total 72K bytes. * * The transformations used are: * IE3264: MSB->LSB conversion, initial permutation, and expansion. * This is done by collecting the 32 even-numbered bits and applying * a 32->64 bit transformation, and then collecting the 32 odd-numbered * bits and applying the same transformation. Since there are only * 32 input bits, the IE3264 transformation table is half the size of * the usual table. * CF6464: Compression, final permutation, and LSB->MSB conversion. * This is done by two trivial 48->32 bit compressions to obtain * a 64-bit block (the bit numbering is given in the "CIFP" table) * followed by a 64->64 bit "cleanup" transformation. (It would * be possible to group the bits in the 64-bit block so that 2 * identical 32->32 bit transformations could be used instead, * saving a factor of 4 in space and possibly 2 in time, but * byte-ordering and other complications rear their ugly head. * Similar opportunities/problems arise in the key schedule * transforms.) * PC1ROT: MSB->LSB, PC1 permutation, rotate, and PC2 permutation. * This admittedly baroque 64->64 bit transformation is used to * produce the first code (in 8*(6+2) format) of the key schedule. * PC2ROT[0]: Inverse PC2 permutation, rotate, and PC2 permutation. * It would be possible to define 15 more transformations, each * with a different rotation, to generate the entire key schedule. * To save space, however, we instead permute each code into the * next by using a transformation that "undoes" the PC2 permutation, * rotates the code, and then applies PC2. Unfortunately, PC2 * transforms 56 bits into 48 bits, dropping 8 bits, so PC2 is not * invertible. We get around that problem by using a modified PC2 * which retains the 8 otherwise-lost bits in the unused low-order * bits of each byte. The low-order bits are cleared when the * codes are stored into the key schedule. * PC2ROT[1]: Same as PC2ROT[0], but with two rotations. * This is faster than applying PC2ROT[0] twice, * * The Bell Labs "salt" (Bob Baldwin): * * The salting is a simple permutation applied to the 48-bit result of E. * Specifically, if bit i (1 <= i <= 24) of the salt is set then bits i and * i+24 of the result are swapped. The salt is thus a 24 bit number, with * 16777216 possible values. (The original salt was 12 bits and could not * swap bits 13..24 with 36..48.) * * It is possible, but ugly, to warp the SPE table to account for the salt * permutation. Fortunately, the conditional bit swapping requires only * about four machine instructions and can be done on-the-fly with about an * 8% performance penalty. */ typedef union { unsigned char b[8]; struct { #if defined(LONG_IS_32_BITS) /* long is often faster than a 32-bit bit field */ long i0; long i1; #else long i0: 32; long i1: 32; #endif } b32; #if defined(B64) B64 b64; #endif } C_block; /* * Convert twenty-four-bit long in host-order * to six bits (and 2 low-order zeroes) per char little-endian format. */ #define TO_SIX_BIT(rslt, src) { \ C_block cvt; \ cvt.b[0] = src; src >>= 6; \ cvt.b[1] = src; src >>= 6; \ cvt.b[2] = src; src >>= 6; \ cvt.b[3] = src; \ rslt = (cvt.b32.i0 & 0x3f3f3f3fL) << 2; \ } /* * These macros may someday permit efficient use of 64-bit integers. */ #define ZERO(d,d0,d1) d0 = 0, d1 = 0 #define LOAD(d,d0,d1,bl) d0 = (bl).b32.i0, d1 = (bl).b32.i1 #define LOADREG(d,d0,d1,s,s0,s1) d0 = s0, d1 = s1 #define OR(d,d0,d1,bl) d0 |= (bl).b32.i0, d1 |= (bl).b32.i1 #define STORE(s,s0,s1,bl) (bl).b32.i0 = s0, (bl).b32.i1 = s1 #define DCL_BLOCK(d,d0,d1) long d0, d1 #if defined(LARGEDATA) /* Waste memory like crazy. Also, do permutations in line */ #define LGCHUNKBITS 3 #define CHUNKBITS (1<<LGCHUNKBITS) #define PERM6464(d,d0,d1,cpp,p) \ LOAD(d,d0,d1,(p)[(0<<CHUNKBITS)+(cpp)[0]]); \ OR (d,d0,d1,(p)[(1<<CHUNKBITS)+(cpp)[1]]); \ OR (d,d0,d1,(p)[(2<<CHUNKBITS)+(cpp)[2]]); \ OR (d,d0,d1,(p)[(3<<CHUNKBITS)+(cpp)[3]]); \ OR (d,d0,d1,(p)[(4<<CHUNKBITS)+(cpp)[4]]); \ OR (d,d0,d1,(p)[(5<<CHUNKBITS)+(cpp)[5]]); \ OR (d,d0,d1,(p)[(6<<CHUNKBITS)+(cpp)[6]]); \ OR (d,d0,d1,(p)[(7<<CHUNKBITS)+(cpp)[7]]); #define PERM3264(d,d0,d1,cpp,p) \ LOAD(d,d0,d1,(p)[(0<<CHUNKBITS)+(cpp)[0]]); \ OR (d,d0,d1,(p)[(1<<CHUNKBITS)+(cpp)[1]]); \ OR (d,d0,d1,(p)[(2<<CHUNKBITS)+(cpp)[2]]); \ OR (d,d0,d1,(p)[(3<<CHUNKBITS)+(cpp)[3]]); #else /* "small data" */ #define LGCHUNKBITS 2 #define CHUNKBITS (1<<LGCHUNKBITS) #define PERM6464(d,d0,d1,cpp,p) \ { C_block tblk; permute(cpp,&tblk,p,8); LOAD (d,d0,d1,tblk); } #define PERM3264(d,d0,d1,cpp,p) \ { C_block tblk; permute(cpp,&tblk,p,4); LOAD (d,d0,d1,tblk); } STATIC void permute(cp, out, p, chars_in) unsigned char *cp; C_block *out; register C_block *p; int chars_in; { register DCL_BLOCK(D,D0,D1); register C_block *tp; register int t; ZERO(D,D0,D1); do { t = *cp++; tp = &p[t&0xf]; OR(D,D0,D1,*tp); p += (1<<CHUNKBITS); tp = &p[t>>4]; OR(D,D0,D1,*tp); p += (1<<CHUNKBITS); } while (--chars_in > 0); STORE(D,D0,D1,*out); } #endif /* LARGEDATA */ /* ===== (mostly) Standard DES Tables ==================== */ static unsigned char IP[] = { /* initial permutation */ 58, 50, 42, 34, 26, 18, 10, 2, 60, 52, 44, 36, 28, 20, 12, 4, 62, 54, 46, 38, 30, 22, 14, 6, 64, 56, 48, 40, 32, 24, 16, 8, 57, 49, 41, 33, 25, 17, 9, 1, 59, 51, 43, 35, 27, 19, 11, 3, 61, 53, 45, 37, 29, 21, 13, 5, 63, 55, 47, 39, 31, 23, 15, 7, }; /* The final permutation is the inverse of IP - no table is necessary */ static unsigned char ExpandTr[] = { /* expansion operation */ 32, 1, 2, 3, 4, 5, 4, 5, 6, 7, 8, 9, 8, 9, 10, 11, 12, 13, 12, 13, 14, 15, 16, 17, 16, 17, 18, 19, 20, 21, 20, 21, 22, 23, 24, 25, 24, 25, 26, 27, 28, 29, 28, 29, 30, 31, 32, 1, }; static unsigned char PC1[] = { /* permuted choice table 1 */ 57, 49, 41, 33, 25, 17, 9, 1, 58, 50, 42, 34, 26, 18, 10, 2, 59, 51, 43, 35, 27, 19, 11, 3, 60, 52, 44, 36, 63, 55, 47, 39, 31, 23, 15, 7, 62, 54, 46, 38, 30, 22, 14, 6, 61, 53, 45, 37, 29, 21, 13, 5, 28, 20, 12, 4, }; static unsigned char Rotates[] = { /* PC1 rotation schedule */ 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1, }; /* note: each "row" of PC2 is left-padded with bits that make it invertible */ static unsigned char PC2[] = { /* permuted choice table 2 */ 9, 18, 14, 17, 11, 24, 1, 5, 22, 25, 3, 28, 15, 6, 21, 10, 35, 38, 23, 19, 12, 4, 26, 8, 43, 54, 16, 7, 27, 20, 13, 2, 0, 0, 41, 52, 31, 37, 47, 55, 0, 0, 30, 40, 51, 45, 33, 48, 0, 0, 44, 49, 39, 56, 34, 53, 0, 0, 46, 42, 50, 36, 29, 32, }; static unsigned char S[8][64] = { /* 48->32 bit substitution tables */ { /* S[1] */ 14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7, 0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8, 4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0, 15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13, }, { /* S[2] */ 15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10, 3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5, 0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15, 13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9, }, { /* S[3] */ 10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8, 13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1, 13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7, 1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12, }, { /* S[4] */ 7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15, 13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9, 10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4, 3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14, }, { /* S[5] */ 2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9, 14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6, 4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14, 11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3, }, { /* S[6] */ 12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11, 10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8, 9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6, 4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13, }, { /* S[7] */ 4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1, 13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6, 1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2, 6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12, }, { /* S[8] */ 13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7, 1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2, 7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8, 2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11, }, }; static unsigned char P32Tr[] = { /* 32-bit permutation function */ 16, 7, 20, 21, 29, 12, 28, 17, 1, 15, 23, 26, 5, 18, 31, 10, 2, 8, 24, 14, 32, 27, 3, 9, 19, 13, 30, 6, 22, 11, 4, 25, }; static unsigned char CIFP[] = { /* compressed/interleaved permutation */ 1, 2, 3, 4, 17, 18, 19, 20, 5, 6, 7, 8, 21, 22, 23, 24, 9, 10, 11, 12, 25, 26, 27, 28, 13, 14, 15, 16, 29, 30, 31, 32, 33, 34, 35, 36, 49, 50, 51, 52, 37, 38, 39, 40, 53, 54, 55, 56, 41, 42, 43, 44, 57, 58, 59, 60, 45, 46, 47, 48, 61, 62, 63, 64, }; static unsigned char itoa64[] = /* 0..63 => ascii-64 */ "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; /* ===== Tables that are initialized at run time ==================== */ static unsigned char a64toi[128]; /* ascii-64 => 0..63 */ /* Initial key schedule permutation */ static C_block PC1ROT[64/CHUNKBITS][1<<CHUNKBITS]; /* Subsequent key schedule rotation permutations */ static C_block PC2ROT[2][64/CHUNKBITS][1<<CHUNKBITS]; /* Initial permutation/expansion table */ static C_block IE3264[32/CHUNKBITS][1<<CHUNKBITS]; /* Table that combines the S, P, and E operations. */ static long SPE[2][8][64]; /* compressed/interleaved => final permutation table */ static C_block CF6464[64/CHUNKBITS][1<<CHUNKBITS]; /* ==================================== */ static C_block constdatablock; /* encryption constant */ static char cryptresult[1+4+4+11+1]; /* encrypted result */ /* * Return a pointer to static data consisting of the "setting" * followed by an encryption produced by the "key" and "setting". */ char * crypt(key, setting) register const char *key; register const char *setting; { register char *encp; register long i; register int t; long salt; int num_iter, salt_size; C_block keyblock, rsltblock; for (i = 0; i < 8; i++) { if ((t = 2*(unsigned char)(*key)) != 0) key++; keyblock.b[i] = t; } if (des_setkey((char *)keyblock.b)) /* also initializes "a64toi" */ return (NULL); encp = &cryptresult[0]; switch (*setting) { case _PASSWORD_EFMT1: /* * Involve the rest of the password 8 characters at a time. */ while (*key) { if (des_cipher((char *)&keyblock, (char *)&keyblock, 0L, 1)) return (NULL); for (i = 0; i < 8; i++) { if ((t = 2*(unsigned char)(*key)) != 0) key++; keyblock.b[i] ^= t; } if (des_setkey((char *)keyblock.b)) return (NULL); } *encp++ = *setting++; /* get iteration count */ num_iter = 0; for (i = 4; --i >= 0; ) { if ((t = (unsigned char)setting[i]) == '\0') t = '.'; encp[i] = t; num_iter = (num_iter<<6) | a64toi[t]; } setting += 4; encp += 4; salt_size = 4; break; default: num_iter = 25; salt_size = 2; } salt = 0; for (i = salt_size; --i >= 0; ) { if ((t = (unsigned char)setting[i]) == '\0') t = '.'; encp[i] = t; salt = (salt<<6) | a64toi[t]; } encp += salt_size; if (des_cipher((char *)&constdatablock, (char *)&rsltblock, salt, num_iter)) return (NULL); /* * Encode the 64 cipher bits as 11 ascii characters. */ i = ((long)((rsltblock.b[0]<<8) | rsltblock.b[1])<<8) | rsltblock.b[2]; encp[3] = itoa64[i&0x3f]; i >>= 6; encp[2] = itoa64[i&0x3f]; i >>= 6; encp[1] = itoa64[i&0x3f]; i >>= 6; encp[0] = itoa64[i]; encp += 4; i = ((long)((rsltblock.b[3]<<8) | rsltblock.b[4])<<8) | rsltblock.b[5]; encp[3] = itoa64[i&0x3f]; i >>= 6; encp[2] = itoa64[i&0x3f]; i >>= 6; encp[1] = itoa64[i&0x3f]; i >>= 6; encp[0] = itoa64[i]; encp += 4; i = ((long)((rsltblock.b[6])<<8) | rsltblock.b[7])<<2; encp[2] = itoa64[i&0x3f]; i >>= 6; encp[1] = itoa64[i&0x3f]; i >>= 6; encp[0] = itoa64[i]; encp[3] = 0; return (cryptresult); } /* * The Key Schedule, filled in by des_setkey() or setkey(). */ #define KS_SIZE 16 static C_block KS[KS_SIZE]; /* * Set up the key schedule from the key. */ int des_setkey(key) register const char *key; { register DCL_BLOCK(K, K0, K1); register C_block *ptabp; register int i; static int des_ready = 0; if (!des_ready) { init_des(); des_ready = 1; } PERM6464(K,K0,K1,(unsigned char *)key,(C_block *)PC1ROT); key = (char *)&KS[0]; STORE(K&~0x03030303L, K0&~0x03030303L, K1, *(C_block *)key); for (i = 1; i < 16; i++) { key += sizeof(C_block); STORE(K,K0,K1,*(C_block *)key); ptabp = (C_block *)PC2ROT[Rotates[i]-1]; PERM6464(K,K0,K1,(unsigned char *)key,ptabp); STORE(K&~0x03030303L, K0&~0x03030303L, K1, *(C_block *)key); } return (0); } /* * Encrypt (or decrypt if num_iter < 0) the 8 chars at "in" with abs(num_iter) * iterations of DES, using the the given 24-bit salt and the pre-computed key * schedule, and store the resulting 8 chars at "out" (in == out is permitted). * * NOTE: the performance of this routine is critically dependent on your * compiler and machine architecture. */ int des_cipher(in, out, salt, num_iter) const char *in; char *out; long salt; int num_iter; { /* variables that we want in registers, most important first */ #if defined(pdp11) register int j; #endif register long L0, L1, R0, R1, k; register C_block *kp; register int ks_inc, loop_count; C_block B; L0 = salt; TO_SIX_BIT(salt, L0); /* convert to 4*(6+2) format */ #if defined(vax) || defined(pdp11) salt = ~salt; /* "x &~ y" is faster than "x & y". */ #define SALT (~salt) #else #define SALT salt #endif #if defined(MUST_ALIGN) B.b[0] = in[0]; B.b[1] = in[1]; B.b[2] = in[2]; B.b[3] = in[3]; B.b[4] = in[4]; B.b[5] = in[5]; B.b[6] = in[6]; B.b[7] = in[7]; LOAD(L,L0,L1,B); #else LOAD(L,L0,L1,*(C_block *)in); #endif LOADREG(R,R0,R1,L,L0,L1); L0 &= 0x55555555L; L1 &= 0x55555555L; L0 = (L0 << 1) | L1; /* L0 is the even-numbered input bits */ R0 &= 0xaaaaaaaaL; R1 = (R1 >> 1) & 0x55555555L; L1 = R0 | R1; /* L1 is the odd-numbered input bits */ STORE(L,L0,L1,B); PERM3264(L,L0,L1,B.b, (C_block *)IE3264); /* even bits */ PERM3264(R,R0,R1,B.b+4,(C_block *)IE3264); /* odd bits */ if (num_iter >= 0) { /* encryption */ kp = &KS[0]; ks_inc = sizeof(*kp); } else { /* decryption */ num_iter = -num_iter; kp = &KS[KS_SIZE-1]; ks_inc = -sizeof(*kp); } while (--num_iter >= 0) { loop_count = 8; do { #define SPTAB(t, i) (*(long *)((unsigned char *)t + i*(sizeof(long)/4))) #if defined(gould) /* use this if B.b[i] is evaluated just once ... */ #define DOXOR(x,y,i) x^=SPTAB(SPE[0][i],B.b[i]); y^=SPTAB(SPE[1][i],B.b[i]); #else #if defined(pdp11) /* use this if your "long" int indexing is slow */ #define DOXOR(x,y,i) j=B.b[i]; x^=SPTAB(SPE[0][i],j); y^=SPTAB(SPE[1][i],j); #else /* use this if "k" is allocated to a register ... */ #define DOXOR(x,y,i) k=B.b[i]; x^=SPTAB(SPE[0][i],k); y^=SPTAB(SPE[1][i],k); #endif #endif #define CRUNCH(p0, p1, q0, q1) \ k = (q0 ^ q1) & SALT; \ B.b32.i0 = k ^ q0 ^ kp->b32.i0; \ B.b32.i1 = k ^ q1 ^ kp->b32.i1; \ kp = (C_block *)((char *)kp+ks_inc); \ \ DOXOR(p0, p1, 0); \ DOXOR(p0, p1, 1); \ DOXOR(p0, p1, 2); \ DOXOR(p0, p1, 3); \ DOXOR(p0, p1, 4); \ DOXOR(p0, p1, 5); \ DOXOR(p0, p1, 6); \ DOXOR(p0, p1, 7); CRUNCH(L0, L1, R0, R1); CRUNCH(R0, R1, L0, L1); } while (--loop_count != 0); kp = (C_block *)((char *)kp-(ks_inc*KS_SIZE)); /* swap L and R */ L0 ^= R0; L1 ^= R1; R0 ^= L0; R1 ^= L1; L0 ^= R0; L1 ^= R1; } /* store the encrypted (or decrypted) result */ L0 = ((L0 >> 3) & 0x0f0f0f0fL) | ((L1 << 1) & 0xf0f0f0f0L); L1 = ((R0 >> 3) & 0x0f0f0f0fL) | ((R1 << 1) & 0xf0f0f0f0L); STORE(L,L0,L1,B); PERM6464(L,L0,L1,B.b, (C_block *)CF6464); #if defined(MUST_ALIGN) STORE(L,L0,L1,B); out[0] = B.b[0]; out[1] = B.b[1]; out[2] = B.b[2]; out[3] = B.b[3]; out[4] = B.b[4]; out[5] = B.b[5]; out[6] = B.b[6]; out[7] = B.b[7]; #else STORE(L,L0,L1,*(C_block *)out); #endif return (0); } /* * Initialize various tables. This need only be done once. It could even be * done at compile time, if the compiler were capable of that sort of thing. */ STATIC void init_des() { register int i, j; register long k; register int tableno; static unsigned char perm[64], tmp32[32]; /* "static" for speed */ /* * table that converts chars "./0-9A-Za-z"to integers 0-63. */ for (i = 0; i < 64; i++) a64toi[itoa64[i]] = i; /* * PC1ROT - bit reverse, then PC1, then Rotate, then PC2. */ for (i = 0; i < 64; i++) perm[i] = 0; for (i = 0; i < 64; i++) { if ((k = PC2[i]) == 0) continue; k += Rotates[0]-1; if ((k%28) < Rotates[0]) k -= 28; k = PC1[k]; if (k > 0) { k--; k = (k|07) - (k&07); k++; } perm[i] = k; } #ifdef DEBUG prtab("pc1tab", perm, 8); #endif init_perm(PC1ROT, perm, 8, 8); /* * PC2ROT - PC2 inverse, then Rotate (once or twice), then PC2. */ for (j = 0; j < 2; j++) { unsigned char pc2inv[64]; for (i = 0; i < 64; i++) perm[i] = pc2inv[i] = 0; for (i = 0; i < 64; i++) { if ((k = PC2[i]) == 0) continue; pc2inv[k-1] = i+1; } for (i = 0; i < 64; i++) { if ((k = PC2[i]) == 0) continue; k += j; if ((k%28) <= j) k -= 28; perm[i] = pc2inv[k]; } #ifdef DEBUG prtab("pc2tab", perm, 8); #endif init_perm(PC2ROT[j], perm, 8, 8); } /* * Bit reverse, then initial permutation, then expansion. */ for (i = 0; i < 8; i++) { for (j = 0; j < 8; j++) { k = (j < 2)? 0: IP[ExpandTr[i*6+j-2]-1]; if (k > 32) k -= 32; else if (k > 0) k--; if (k > 0) { k--; k = (k|07) - (k&07); k++; } perm[i*8+j] = k; } } #ifdef DEBUG prtab("ietab", perm, 8); #endif init_perm(IE3264, perm, 4, 8); /* * Compression, then final permutation, then bit reverse. */ for (i = 0; i < 64; i++) { k = IP[CIFP[i]-1]; if (k > 0) { k--; k = (k|07) - (k&07); k++; } perm[k-1] = i+1; } #ifdef DEBUG prtab("cftab", perm, 8); #endif init_perm(CF6464, perm, 8, 8); /* * SPE table */ for (i = 0; i < 48; i++) perm[i] = P32Tr[ExpandTr[i]-1]; for (tableno = 0; tableno < 8; tableno++) { for (j = 0; j < 64; j++) { k = (((j >> 0) &01) << 5)| (((j >> 1) &01) << 3)| (((j >> 2) &01) << 2)| (((j >> 3) &01) << 1)| (((j >> 4) &01) << 0)| (((j >> 5) &01) << 4); k = S[tableno][k]; k = (((k >> 3)&01) << 0)| (((k >> 2)&01) << 1)| (((k >> 1)&01) << 2)| (((k >> 0)&01) << 3); for (i = 0; i < 32; i++) tmp32[i] = 0; for (i = 0; i < 4; i++) tmp32[4 * tableno + i] = (k >> i) & 01; k = 0; for (i = 24; --i >= 0; ) k = (k<<1) | tmp32[perm[i]-1]; TO_SIX_BIT(SPE[0][tableno][j], k); k = 0; for (i = 24; --i >= 0; ) k = (k<<1) | tmp32[perm[i+24]-1]; TO_SIX_BIT(SPE[1][tableno][j], k); } } } /* * Initialize "perm" to represent transformation "p", which rearranges * (perhaps with expansion and/or contraction) one packed array of bits * (of size "chars_in" characters) into another array (of size "chars_out" * characters). * * "perm" must be all-zeroes on entry to this routine. */ STATIC void init_perm(perm, p, chars_in, chars_out) C_block perm[64/CHUNKBITS][1<<CHUNKBITS]; unsigned char p[64]; int chars_in, chars_out; { register int i, j, k, l; for (k = 0; k < chars_out*8; k++) { /* each output bit position */ l = p[k] - 1; /* where this bit comes from */ if (l < 0) continue; /* output bit is always 0 */ i = l>>LGCHUNKBITS; /* which chunk this bit comes from */ l = 1<<(l&(CHUNKBITS-1)); /* mask for this bit */ for (j = 0; j < (1<<CHUNKBITS); j++) { /* each chunk value */ if ((j & l) != 0) perm[i][j].b[k>>3] |= 1<<(k&07); } } } /* * "setkey" routine (for backwards compatibility) */ int setkey(key) register const char *key; { register int i, j, k; C_block keyblock; for (i = 0; i < 8; i++) { k = 0; for (j = 0; j < 8; j++) { k <<= 1; k |= (unsigned char)*key++; } keyblock.b[i] = k; } return (des_setkey((char *)keyblock.b)); } /* * "encrypt" routine (for backwards compatibility) */ int encrypt(block, flag) register char *block; int flag; { register int i, j, k; C_block cblock; for (i = 0; i < 8; i++) { k = 0; for (j = 0; j < 8; j++) { k <<= 1; k |= (unsigned char)*block++; } cblock.b[i] = k; } if (des_cipher((char *)&cblock, (char *)&cblock, 0L, (flag ? -1: 1))) return (1); for (i = 7; i >= 0; i--) { k = cblock.b[i]; for (j = 7; j >= 0; j--) { *--block = k&01; k >>= 1; } } return (0); } #ifdef DEBUG STATIC void prtab(s, t, num_rows) char *s; unsigned char *t; int num_rows; { register int i, j; (void)printf("%s:\n", s); for (i = 0; i < num_rows; i++) { for (j = 0; j < 8; j++) { (void)printf("%3d", t[i*8+j]); } (void)printf("\n"); } (void)printf("\n"); } #endif