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Diffstat (limited to 'libbb/pw_encrypt_des.c')
-rw-r--r-- | libbb/pw_encrypt_des.c | 703 |
1 files changed, 703 insertions, 0 deletions
diff --git a/libbb/pw_encrypt_des.c b/libbb/pw_encrypt_des.c new file mode 100644 index 0000000..637765e --- /dev/null +++ b/libbb/pw_encrypt_des.c @@ -0,0 +1,703 @@ +/* + * FreeSec: libcrypt for NetBSD + * + * Copyright (c) 1994 David Burren + * All rights reserved. + * + * Adapted for FreeBSD-2.0 by Geoffrey M. Rehmet + * this file should now *only* export crypt(), in order to make + * binaries of libcrypt exportable from the USA + * + * Adapted for FreeBSD-4.0 by Mark R V Murray + * this file should now *only* export crypt_des(), in order to make + * a module that can be optionally included in libcrypt. + * + * 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 author nor the names of other contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. + * + * This is an original implementation of the DES and the crypt(3) interfaces + * by David Burren <davidb@werj.com.au>. + * + * An excellent reference on the underlying algorithm (and related + * algorithms) is: + * + * B. Schneier, Applied Cryptography: protocols, algorithms, + * and source code in C, John Wiley & Sons, 1994. + * + * Note that in that book's description of DES the lookups for the initial, + * pbox, and final permutations are inverted (this has been brought to the + * attention of the author). A list of errata for this book has been + * posted to the sci.crypt newsgroup by the author and is available for FTP. + * + * ARCHITECTURE ASSUMPTIONS: + * It is assumed that the 8-byte arrays passed by reference can be + * addressed as arrays of uint32_t's (ie. the CPU is not picky about + * alignment). + */ + +/* A pile of data */ +static const uint8_t IP[64] = { + 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 +}; + +static const uint8_t key_perm[56] = { + 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 const uint8_t key_shifts[16] = { + 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1 +}; + +static const uint8_t comp_perm[48] = { + 14, 17, 11, 24, 1, 5, 3, 28, 15, 6, 21, 10, + 23, 19, 12, 4, 26, 8, 16, 7, 27, 20, 13, 2, + 41, 52, 31, 37, 47, 55, 30, 40, 51, 45, 33, 48, + 44, 49, 39, 56, 34, 53, 46, 42, 50, 36, 29, 32 +}; + +/* + * No E box is used, as it's replaced by some ANDs, shifts, and ORs. + */ + +static const uint8_t sbox[8][64] = { + { + 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 + }, + { + 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 + }, + { + 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 + }, + { + 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 + }, + { + 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 + }, + { + 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 + }, + { + 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 + }, + { + 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 const uint8_t pbox[32] = { + 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 const uint32_t bits32[32] = +{ + 0x80000000, 0x40000000, 0x20000000, 0x10000000, + 0x08000000, 0x04000000, 0x02000000, 0x01000000, + 0x00800000, 0x00400000, 0x00200000, 0x00100000, + 0x00080000, 0x00040000, 0x00020000, 0x00010000, + 0x00008000, 0x00004000, 0x00002000, 0x00001000, + 0x00000800, 0x00000400, 0x00000200, 0x00000100, + 0x00000080, 0x00000040, 0x00000020, 0x00000010, + 0x00000008, 0x00000004, 0x00000002, 0x00000001 +}; + +static const uint8_t bits8[8] = { 0x80, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x01 }; + + +static int +ascii_to_bin(char ch) +{ + if (ch > 'z') + return 0; + if (ch >= 'a') + return (ch - 'a' + 38); + if (ch > 'Z') + return 0; + if (ch >= 'A') + return (ch - 'A' + 12); + if (ch > '9') + return 0; + if (ch >= '.') + return (ch - '.'); + return 0; +} + + +/* Static stuff that stays resident and doesn't change after + * being initialized, and therefore doesn't need to be made + * reentrant. */ +struct const_des_ctx { + uint8_t init_perm[64], final_perm[64]; /* referenced 2 times each */ + uint8_t m_sbox[4][4096]; /* 5 times */ +}; +#define C (*cctx) +#define init_perm (C.init_perm ) +#define final_perm (C.final_perm) +#define m_sbox (C.m_sbox ) + +static struct const_des_ctx* +const_des_init(void) +{ + int i, j, b; + uint8_t u_sbox[8][64]; + struct const_des_ctx *cctx; + + cctx = xmalloc(sizeof(*cctx)); + + /* + * Invert the S-boxes, reordering the input bits. + */ + for (i = 0; i < 8; i++) { + for (j = 0; j < 64; j++) { + b = (j & 0x20) | ((j & 1) << 4) | ((j >> 1) & 0xf); + u_sbox[i][j] = sbox[i][b]; + } + } + + /* + * Convert the inverted S-boxes into 4 arrays of 8 bits. + * Each will handle 12 bits of the S-box input. + */ + for (b = 0; b < 4; b++) + for (i = 0; i < 64; i++) + for (j = 0; j < 64; j++) + m_sbox[b][(i << 6) | j] = + (uint8_t)((u_sbox[(b << 1)][i] << 4) | + u_sbox[(b << 1) + 1][j]); + + /* + * Set up the initial & final permutations into a useful form. + */ + for (i = 0; i < 64; i++) { + final_perm[i] = IP[i] - 1; + init_perm[final_perm[i]] = (uint8_t)i; + } + + return cctx; +} + + +struct des_ctx { + const struct const_des_ctx *const_ctx; + uint32_t saltbits; /* referenced 5 times */ + uint32_t old_salt; /* 3 times */ + uint32_t old_rawkey0, old_rawkey1; /* 3 times each */ + uint8_t un_pbox[32]; /* 2 times */ + uint8_t inv_comp_perm[56]; /* 3 times */ + uint8_t inv_key_perm[64]; /* 3 times */ + uint32_t en_keysl[16], en_keysr[16]; /* 2 times each */ + uint32_t de_keysl[16], de_keysr[16]; /* 2 times each */ + uint32_t ip_maskl[8][256], ip_maskr[8][256]; /* 9 times each */ + uint32_t fp_maskl[8][256], fp_maskr[8][256]; /* 9 times each */ + uint32_t key_perm_maskl[8][128], key_perm_maskr[8][128]; /* 9 times */ + uint32_t comp_maskl[8][128], comp_maskr[8][128]; /* 9 times each */ + uint32_t psbox[4][256]; /* 5 times */ +}; +#define D (*ctx) +#define const_ctx (D.const_ctx ) +#define saltbits (D.saltbits ) +#define old_salt (D.old_salt ) +#define old_rawkey0 (D.old_rawkey0 ) +#define old_rawkey1 (D.old_rawkey1 ) +#define un_pbox (D.un_pbox ) +#define inv_comp_perm (D.inv_comp_perm ) +#define inv_key_perm (D.inv_key_perm ) +#define en_keysl (D.en_keysl ) +#define en_keysr (D.en_keysr ) +#define de_keysl (D.de_keysl ) +#define de_keysr (D.de_keysr ) +#define ip_maskl (D.ip_maskl ) +#define ip_maskr (D.ip_maskr ) +#define fp_maskl (D.fp_maskl ) +#define fp_maskr (D.fp_maskr ) +#define key_perm_maskl (D.key_perm_maskl ) +#define key_perm_maskr (D.key_perm_maskr ) +#define comp_maskl (D.comp_maskl ) +#define comp_maskr (D.comp_maskr ) +#define psbox (D.psbox ) + +static struct des_ctx* +des_init(struct des_ctx *ctx, const struct const_des_ctx *cctx) +{ + int i, j, b, k, inbit, obit; + uint32_t *p, *il, *ir, *fl, *fr; + const uint32_t *bits28, *bits24; + + if (!ctx) + ctx = xmalloc(sizeof(*ctx)); + const_ctx = cctx; + + old_rawkey0 = old_rawkey1 = 0L; + saltbits = 0L; + old_salt = 0L; + bits28 = bits32 + 4; + bits24 = bits28 + 4; + + /* + * Initialise the inverted key permutation. + */ + for (i = 0; i < 64; i++) { + inv_key_perm[i] = 255; + } + + /* + * Invert the key permutation and initialise the inverted key + * compression permutation. + */ + for (i = 0; i < 56; i++) { + inv_key_perm[key_perm[i] - 1] = (uint8_t)i; + inv_comp_perm[i] = 255; + } + + /* + * Invert the key compression permutation. + */ + for (i = 0; i < 48; i++) { + inv_comp_perm[comp_perm[i] - 1] = (uint8_t)i; + } + + /* + * Set up the OR-mask arrays for the initial and final permutations, + * and for the key initial and compression permutations. + */ + for (k = 0; k < 8; k++) { + for (i = 0; i < 256; i++) { + il = &ip_maskl[k][i]; + ir = &ip_maskr[k][i]; + fl = &fp_maskl[k][i]; + fr = &fp_maskr[k][i]; + *il = 0; + *ir = 0; + *fl = 0; + *fr = 0; + for (j = 0; j < 8; j++) { + inbit = 8 * k + j; + if (i & bits8[j]) { + obit = init_perm[inbit]; + if (obit < 32) + *il |= bits32[obit]; + else + *ir |= bits32[obit - 32]; + obit = final_perm[inbit]; + if (obit < 32) + *fl |= bits32[obit]; + else + *fr |= bits32[obit - 32]; + } + } + } + for (i = 0; i < 128; i++) { + il = &key_perm_maskl[k][i]; + ir = &key_perm_maskr[k][i]; + *il = 0; + *ir = 0; + for (j = 0; j < 7; j++) { + inbit = 8 * k + j; + if (i & bits8[j + 1]) { + obit = inv_key_perm[inbit]; + if (obit == 255) + continue; + if (obit < 28) + *il |= bits28[obit]; + else + *ir |= bits28[obit - 28]; + } + } + il = &comp_maskl[k][i]; + ir = &comp_maskr[k][i]; + *il = 0; + *ir = 0; + for (j = 0; j < 7; j++) { + inbit = 7 * k + j; + if (i & bits8[j + 1]) { + obit = inv_comp_perm[inbit]; + if (obit == 255) + continue; + if (obit < 24) + *il |= bits24[obit]; + else + *ir |= bits24[obit - 24]; + } + } + } + } + + /* + * Invert the P-box permutation, and convert into OR-masks for + * handling the output of the S-box arrays setup above. + */ + for (i = 0; i < 32; i++) + un_pbox[pbox[i] - 1] = (uint8_t)i; + + for (b = 0; b < 4; b++) { + for (i = 0; i < 256; i++) { + p = &psbox[b][i]; + *p = 0; + for (j = 0; j < 8; j++) { + if (i & bits8[j]) + *p |= bits32[un_pbox[8 * b + j]]; + } + } + } + + return ctx; +} + + +static void +setup_salt(struct des_ctx *ctx, uint32_t salt) +{ +// const struct const_des_ctx *cctx = const_ctx; + uint32_t obit, saltbit; + int i; + + if (salt == old_salt) + return; + old_salt = salt; + + saltbits = 0L; + saltbit = 1; + obit = 0x800000; + for (i = 0; i < 24; i++) { + if (salt & saltbit) + saltbits |= obit; + saltbit <<= 1; + obit >>= 1; + } +} + +static void +des_setkey(struct des_ctx *ctx, const char *key) +{ +// const struct const_des_ctx *cctx = const_ctx; + uint32_t k0, k1, rawkey0, rawkey1; + int shifts, round; + + rawkey0 = ntohl(*(const uint32_t *) key); + rawkey1 = ntohl(*(const uint32_t *) (key + 4)); + + if ((rawkey0 | rawkey1) + && rawkey0 == old_rawkey0 + && rawkey1 == old_rawkey1 + ) { + /* + * Already setup for this key. + * This optimisation fails on a zero key (which is weak and + * has bad parity anyway) in order to simplify the starting + * conditions. + */ + return; + } + old_rawkey0 = rawkey0; + old_rawkey1 = rawkey1; + + /* + * Do key permutation and split into two 28-bit subkeys. + */ + k0 = key_perm_maskl[0][rawkey0 >> 25] + | key_perm_maskl[1][(rawkey0 >> 17) & 0x7f] + | key_perm_maskl[2][(rawkey0 >> 9) & 0x7f] + | key_perm_maskl[3][(rawkey0 >> 1) & 0x7f] + | key_perm_maskl[4][rawkey1 >> 25] + | key_perm_maskl[5][(rawkey1 >> 17) & 0x7f] + | key_perm_maskl[6][(rawkey1 >> 9) & 0x7f] + | key_perm_maskl[7][(rawkey1 >> 1) & 0x7f]; + k1 = key_perm_maskr[0][rawkey0 >> 25] + | key_perm_maskr[1][(rawkey0 >> 17) & 0x7f] + | key_perm_maskr[2][(rawkey0 >> 9) & 0x7f] + | key_perm_maskr[3][(rawkey0 >> 1) & 0x7f] + | key_perm_maskr[4][rawkey1 >> 25] + | key_perm_maskr[5][(rawkey1 >> 17) & 0x7f] + | key_perm_maskr[6][(rawkey1 >> 9) & 0x7f] + | key_perm_maskr[7][(rawkey1 >> 1) & 0x7f]; + /* + * Rotate subkeys and do compression permutation. + */ + shifts = 0; + for (round = 0; round < 16; round++) { + uint32_t t0, t1; + + shifts += key_shifts[round]; + + t0 = (k0 << shifts) | (k0 >> (28 - shifts)); + t1 = (k1 << shifts) | (k1 >> (28 - shifts)); + + de_keysl[15 - round] = + en_keysl[round] = comp_maskl[0][(t0 >> 21) & 0x7f] + | comp_maskl[1][(t0 >> 14) & 0x7f] + | comp_maskl[2][(t0 >> 7) & 0x7f] + | comp_maskl[3][t0 & 0x7f] + | comp_maskl[4][(t1 >> 21) & 0x7f] + | comp_maskl[5][(t1 >> 14) & 0x7f] + | comp_maskl[6][(t1 >> 7) & 0x7f] + | comp_maskl[7][t1 & 0x7f]; + + de_keysr[15 - round] = + en_keysr[round] = comp_maskr[0][(t0 >> 21) & 0x7f] + | comp_maskr[1][(t0 >> 14) & 0x7f] + | comp_maskr[2][(t0 >> 7) & 0x7f] + | comp_maskr[3][t0 & 0x7f] + | comp_maskr[4][(t1 >> 21) & 0x7f] + | comp_maskr[5][(t1 >> 14) & 0x7f] + | comp_maskr[6][(t1 >> 7) & 0x7f] + | comp_maskr[7][t1 & 0x7f]; + } +} + + +static int +do_des(struct des_ctx *ctx, uint32_t l_in, uint32_t r_in, uint32_t *l_out, uint32_t *r_out, int count) +{ + const struct const_des_ctx *cctx = const_ctx; + /* + * l_in, r_in, l_out, and r_out are in pseudo-"big-endian" format. + */ + uint32_t l, r, *kl, *kr, *kl1, *kr1; + uint32_t f = f; /* silence gcc */ + uint32_t r48l, r48r; + int round; + + /* + * Encrypting + */ + kl1 = en_keysl; + kr1 = en_keysr; + + /* + * Do initial permutation (IP). + */ + l = ip_maskl[0][l_in >> 24] + | ip_maskl[1][(l_in >> 16) & 0xff] + | ip_maskl[2][(l_in >> 8) & 0xff] + | ip_maskl[3][l_in & 0xff] + | ip_maskl[4][r_in >> 24] + | ip_maskl[5][(r_in >> 16) & 0xff] + | ip_maskl[6][(r_in >> 8) & 0xff] + | ip_maskl[7][r_in & 0xff]; + r = ip_maskr[0][l_in >> 24] + | ip_maskr[1][(l_in >> 16) & 0xff] + | ip_maskr[2][(l_in >> 8) & 0xff] + | ip_maskr[3][l_in & 0xff] + | ip_maskr[4][r_in >> 24] + | ip_maskr[5][(r_in >> 16) & 0xff] + | ip_maskr[6][(r_in >> 8) & 0xff] + | ip_maskr[7][r_in & 0xff]; + + while (count--) { + /* + * Do each round. + */ + kl = kl1; + kr = kr1; + round = 16; + while (round--) { + /* + * Expand R to 48 bits (simulate the E-box). + */ + r48l = ((r & 0x00000001) << 23) + | ((r & 0xf8000000) >> 9) + | ((r & 0x1f800000) >> 11) + | ((r & 0x01f80000) >> 13) + | ((r & 0x001f8000) >> 15); + + r48r = ((r & 0x0001f800) << 7) + | ((r & 0x00001f80) << 5) + | ((r & 0x000001f8) << 3) + | ((r & 0x0000001f) << 1) + | ((r & 0x80000000) >> 31); + /* + * Do salting for crypt() and friends, and + * XOR with the permuted key. + */ + f = (r48l ^ r48r) & saltbits; + r48l ^= f ^ *kl++; + r48r ^= f ^ *kr++; + /* + * Do sbox lookups (which shrink it back to 32 bits) + * and do the pbox permutation at the same time. + */ + f = psbox[0][m_sbox[0][r48l >> 12]] + | psbox[1][m_sbox[1][r48l & 0xfff]] + | psbox[2][m_sbox[2][r48r >> 12]] + | psbox[3][m_sbox[3][r48r & 0xfff]]; + /* + * Now that we've permuted things, complete f(). + */ + f ^= l; + l = r; + r = f; + } + r = l; + l = f; + } + /* + * Do final permutation (inverse of IP). + */ + *l_out = fp_maskl[0][l >> 24] + | fp_maskl[1][(l >> 16) & 0xff] + | fp_maskl[2][(l >> 8) & 0xff] + | fp_maskl[3][l & 0xff] + | fp_maskl[4][r >> 24] + | fp_maskl[5][(r >> 16) & 0xff] + | fp_maskl[6][(r >> 8) & 0xff] + | fp_maskl[7][r & 0xff]; + *r_out = fp_maskr[0][l >> 24] + | fp_maskr[1][(l >> 16) & 0xff] + | fp_maskr[2][(l >> 8) & 0xff] + | fp_maskr[3][l & 0xff] + | fp_maskr[4][r >> 24] + | fp_maskr[5][(r >> 16) & 0xff] + | fp_maskr[6][(r >> 8) & 0xff] + | fp_maskr[7][r & 0xff]; + return 0; +} + +#define DES_OUT_BUFSIZE 21 + +static char * +des_crypt(struct des_ctx *ctx, char output[21], const unsigned char *key, const unsigned char *setting) +{ + uint32_t salt, l, r0, r1, keybuf[2]; + uint8_t *p, *q; + + /* + * Copy the key, shifting each character up by one bit + * and padding with zeros. + */ + q = (uint8_t *)keybuf; + while (q - (uint8_t *)keybuf - 8) { + *q++ = *key << 1; + if (*(q - 1)) + key++; + } + des_setkey(ctx, (char *)keybuf); + + /* + * setting - 2 bytes of salt + * key - up to 8 characters + */ + salt = (ascii_to_bin(setting[1]) << 6) + | ascii_to_bin(setting[0]); + + output[0] = setting[0]; + /* + * If the encrypted password that the salt was extracted from + * is only 1 character long, the salt will be corrupted. We + * need to ensure that the output string doesn't have an extra + * NUL in it! + */ + output[1] = setting[1] ? setting[1] : output[0]; + + p = (uint8_t *)output + 2; + + setup_salt(ctx, salt); + /* + * Do it. + */ + do_des(ctx, 0L, 0L, &r0, &r1, 25 /* count */); + + /* + * Now encode the result... + */ + l = (r0 >> 8); + *p++ = ascii64[(l >> 18) & 0x3f]; + *p++ = ascii64[(l >> 12) & 0x3f]; + *p++ = ascii64[(l >> 6) & 0x3f]; + *p++ = ascii64[l & 0x3f]; + + l = (r0 << 16) | ((r1 >> 16) & 0xffff); + *p++ = ascii64[(l >> 18) & 0x3f]; + *p++ = ascii64[(l >> 12) & 0x3f]; + *p++ = ascii64[(l >> 6) & 0x3f]; + *p++ = ascii64[l & 0x3f]; + + l = r1 << 2; + *p++ = ascii64[(l >> 12) & 0x3f]; + *p++ = ascii64[(l >> 6) & 0x3f]; + *p++ = ascii64[l & 0x3f]; + *p = 0; + + return output; +} + +// des_setkey never fails + +#undef C +#undef init_perm +#undef final_perm +#undef m_sbox +#undef D +#undef const_ctx +#undef saltbits +#undef old_salt +#undef old_rawkey0 +#undef old_rawkey1 +#undef un_pbox +#undef inv_comp_perm +#undef inv_key_perm +#undef en_keysl +#undef en_keysr +#undef de_keysl +#undef de_keysr +#undef ip_maskl +#undef ip_maskr +#undef fp_maskl +#undef fp_maskr +#undef key_perm_maskl +#undef key_perm_maskr +#undef comp_maskl +#undef comp_maskr +#undef psbox |