/* * 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 . * * 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 u_int32_t's (ie. the CPU is not picky about * alignment). */ #include #include #include #include #include #include #include #include "libcrypt.h" #include "des_tables.c" /* Re-entrantify me -- all this junk needs to be in * struct crypt_data to make this really reentrant... */ static u_int32_t en_keysl[16], en_keysr[16]; static u_int32_t de_keysl[16], de_keysr[16]; static u_int32_t saltbits; static u_int32_t old_salt; static u_int32_t old_rawkey0, old_rawkey1; /* A pile of data */ static const u_char ascii64[] = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; static const u_char key_shifts[16] = { 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1 }; static const u_int32_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 u_char 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 void des_init(void) { static int des_initialised = 0; if (des_initialised==1) return; old_rawkey0 = old_rawkey1 = 0L; saltbits = 0L; old_salt = 0L; des_initialised = 1; } static void setup_salt(u_int32_t salt) { u_int32_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(const char *key) { u_int32_t k0, k1, rawkey0, rawkey1; int shifts, round; des_init(); rawkey0 = ntohl(*(const u_int32_t *) key); rawkey1 = ntohl(*(const u_int32_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++) { u_int32_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( u_int32_t l_in, u_int32_t r_in, u_int32_t *l_out, u_int32_t *r_out, int count) { /* l_in, r_in, l_out, and r_out are in pseudo-"big-endian" format. */ u_int32_t l, r, *kl, *kr, *kl1, *kr1; u_int32_t f, r48l, r48r; int round; if (count == 0) { return 1; } if (count > 0) { /* Encrypting */ kl1 = en_keysl; kr1 = en_keysr; } else { /* Decrypting */ count = -count; kl1 = de_keysl; kr1 = de_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; do { /* 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; } while (--round); 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); } #if 0 static int des_cipher(const char *in, char *out, u_int32_t salt, int count) { u_int32_t l_out, r_out, rawl, rawr; int retval; union { u_int32_t *ui32; const char *c; } trans; des_init(); setup_salt(salt); trans.c = in; rawl = ntohl(*trans.ui32++); rawr = ntohl(*trans.ui32); retval = do_des(rawl, rawr, &l_out, &r_out, count); trans.c = out; *trans.ui32++ = htonl(l_out); *trans.ui32 = htonl(r_out); return(retval); } #endif void setkey(const char *key) { int i, j; u_int32_t packed_keys[2]; u_char *p; p = (u_char *) packed_keys; for (i = 0; i < 8; i++) { p[i] = 0; for (j = 0; j < 8; j++) if (*key++ & 1) p[i] |= bits8[j]; } des_setkey((char *)p); } void encrypt(char *block, int flag) { u_int32_t io[2]; u_char *p; int i, j; des_init(); setup_salt(0L); p = (u_char*)block; for (i = 0; i < 2; i++) { io[i] = 0L; for (j = 0; j < 32; j++) if (*p++ & 1) io[i] |= bits32[j]; } do_des(io[0], io[1], io, io + 1, flag ? -1 : 1); for (i = 0; i < 2; i++) for (j = 0; j < 32; j++) block[(i << 5) | j] = (io[i] & bits32[j]) ? 1 : 0; } char *__des_crypt(const unsigned char *key, const unsigned char *setting) { u_int32_t count, salt, l, r0, r1, keybuf[2]; u_char *p, *q; static char output[21]; des_init(); /* * Copy the key, shifting each character up by one bit * and padding with zeros. */ q = (u_char *)keybuf; while (q - (u_char *)keybuf - 8) { *q++ = *key << 1; if (*(q - 1)) key++; } des_setkey((char *)keybuf); #if 0 if (*setting == _PASSWORD_EFMT1) { int i; /* * "new"-style: * setting - underscore, 4 bytes of count, 4 bytes of salt * key - unlimited characters */ for (i = 1, count = 0L; i < 5; i++) count |= ascii_to_bin(setting[i]) << ((i - 1) * 6); for (i = 5, salt = 0L; i < 9; i++) salt |= ascii_to_bin(setting[i]) << ((i - 5) * 6); while (*key) { /* * Encrypt the key with itself. */ if (des_cipher((char *)keybuf, (char *)keybuf, 0L, 1)) return(NULL); /* * And XOR with the next 8 characters of the key. */ q = (u_char *)keybuf; while (q - (u_char *)keybuf - 8 && *key) *q++ ^= *key++ << 1; des_setkey((char *)keybuf); } strncpy(output, setting, 9); /* * Double check that we weren't given a short setting. * If we were, the above code will probably have created * wierd values for count and salt, but we don't really care. * Just make sure the output string doesn't have an extra * NUL in it. */ output[9] = '\0'; p = (u_char *)output + strlen(output); } else #endif { /* * "old"-style: * setting - 2 bytes of salt * key - up to 8 characters */ count = 25; 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 = (u_char *)output + 2; } setup_salt(salt); /* * Do it. */ if (do_des(0L, 0L, &r0, &r1, (int)count)) return(NULL); /* * 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); }