/* $OpenBSD: des_key.c,v 1.1 2024/08/31 15:56:09 jsing Exp $ */ /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. * * 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 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * "This product includes cryptographic software written by * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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. * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */ #include #include #include "des_local.h" int DES_check_key = 0; /* defaults to false */ LCRYPTO_ALIAS(DES_check_key); static const unsigned char odd_parity[256] = { 1, 1, 2, 2, 4, 4, 7, 7, 8, 8, 11, 11, 13, 13, 14, 14, 16, 16, 19, 19, 21, 21, 22, 22, 25, 25, 26, 26, 28, 28, 31, 31, 32, 32, 35, 35, 37, 37, 38, 38, 41, 41, 42, 42, 44, 44, 47, 47, 49, 49, 50, 50, 52, 52, 55, 55, 56, 56, 59, 59, 61, 61, 62, 62, 64, 64, 67, 67, 69, 69, 70, 70, 73, 73, 74, 74, 76, 76, 79, 79, 81, 81, 82, 82, 84, 84, 87, 87, 88, 88, 91, 91, 93, 93, 94, 94, 97, 97, 98, 98, 100, 100, 103, 103, 104, 104, 107, 107, 109, 109, 110, 110, 112, 112, 115, 115, 117, 117, 118, 118, 121, 121, 122, 122, 124, 124, 127, 127, 128, 128, 131, 131, 133, 133, 134, 134, 137, 137, 138, 138, 140, 140, 143, 143, 145, 145, 146, 146, 148, 148, 151, 151, 152, 152, 155, 155, 157, 157, 158, 158, 161, 161, 162, 162, 164, 164, 167, 167, 168, 168, 171, 171, 173, 173, 174, 174, 176, 176, 179, 179, 181, 181, 182, 182, 185, 185, 186, 186, 188, 188, 191, 191, 193, 193, 194, 194, 196, 196, 199, 199, 200, 200, 203, 203, 205, 205, 206, 206, 208, 208, 211, 211, 213, 213, 214, 214, 217, 217, 218, 218, 220, 220, 223, 223, 224, 224, 227, 227, 229, 229, 230, 230, 233, 233, 234, 234, 236, 236, 239, 239, 241, 241, 242, 242, 244, 244, 247, 247, 248, 248, 251, 251, 253, 253, 254, 254, }; void DES_set_odd_parity(DES_cblock *key) { unsigned int i; for (i = 0; i < DES_KEY_SZ; i++) (*key)[i] = odd_parity[(*key)[i]]; } LCRYPTO_ALIAS(DES_set_odd_parity); int DES_check_key_parity(const_DES_cblock *key) { unsigned int i; for (i = 0; i < DES_KEY_SZ; i++) { if ((*key)[i] != odd_parity[(*key)[i]]) return (0); } return (1); } LCRYPTO_ALIAS(DES_check_key_parity); /* Weak and semi weak keys as taken from * %A D.W. Davies * %A W.L. Price * %T Security for Computer Networks * %I John Wiley & Sons * %D 1984 * Many thanks to smb@ulysses.att.com (Steven Bellovin) for the reference * (and actual cblock values). */ #define NUM_WEAK_KEY 16 static const DES_cblock weak_keys[NUM_WEAK_KEY] = { /* weak keys */ {0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01}, {0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE}, {0x1F, 0x1F, 0x1F, 0x1F, 0x0E, 0x0E, 0x0E, 0x0E}, {0xE0, 0xE0, 0xE0, 0xE0, 0xF1, 0xF1, 0xF1, 0xF1}, /* semi-weak keys */ {0x01, 0xFE, 0x01, 0xFE, 0x01, 0xFE, 0x01, 0xFE}, {0xFE, 0x01, 0xFE, 0x01, 0xFE, 0x01, 0xFE, 0x01}, {0x1F, 0xE0, 0x1F, 0xE0, 0x0E, 0xF1, 0x0E, 0xF1}, {0xE0, 0x1F, 0xE0, 0x1F, 0xF1, 0x0E, 0xF1, 0x0E}, {0x01, 0xE0, 0x01, 0xE0, 0x01, 0xF1, 0x01, 0xF1}, {0xE0, 0x01, 0xE0, 0x01, 0xF1, 0x01, 0xF1, 0x01}, {0x1F, 0xFE, 0x1F, 0xFE, 0x0E, 0xFE, 0x0E, 0xFE}, {0xFE, 0x1F, 0xFE, 0x1F, 0xFE, 0x0E, 0xFE, 0x0E}, {0x01, 0x1F, 0x01, 0x1F, 0x01, 0x0E, 0x01, 0x0E}, {0x1F, 0x01, 0x1F, 0x01, 0x0E, 0x01, 0x0E, 0x01}, {0xE0, 0xFE, 0xE0, 0xFE, 0xF1, 0xFE, 0xF1, 0xFE}, {0xFE, 0xE0, 0xFE, 0xE0, 0xFE, 0xF1, 0xFE, 0xF1}, }; int DES_is_weak_key(const_DES_cblock *key) { unsigned int i; for (i = 0; i < NUM_WEAK_KEY; i++) if (memcmp(weak_keys[i], key, sizeof(DES_cblock)) == 0) return 1; return 0; } LCRYPTO_ALIAS(DES_is_weak_key); /* NOW DEFINED IN des_local.h * See ecb_encrypt.c for a pseudo description of these macros. * #define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\ * (b)^=(t),\ * (a)=((a)^((t)<<(n)))) */ #define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)), \ (a)=(a)^(t)^(t>>(16-(n)))) static const DES_LONG des_skb[8][64] = { { /* for C bits (numbered as per FIPS 46) 1 2 3 4 5 6 */ 0x00000000L, 0x00000010L, 0x20000000L, 0x20000010L, 0x00010000L, 0x00010010L, 0x20010000L, 0x20010010L, 0x00000800L, 0x00000810L, 0x20000800L, 0x20000810L, 0x00010800L, 0x00010810L, 0x20010800L, 0x20010810L, 0x00000020L, 0x00000030L, 0x20000020L, 0x20000030L, 0x00010020L, 0x00010030L, 0x20010020L, 0x20010030L, 0x00000820L, 0x00000830L, 0x20000820L, 0x20000830L, 0x00010820L, 0x00010830L, 0x20010820L, 0x20010830L, 0x00080000L, 0x00080010L, 0x20080000L, 0x20080010L, 0x00090000L, 0x00090010L, 0x20090000L, 0x20090010L, 0x00080800L, 0x00080810L, 0x20080800L, 0x20080810L, 0x00090800L, 0x00090810L, 0x20090800L, 0x20090810L, 0x00080020L, 0x00080030L, 0x20080020L, 0x20080030L, 0x00090020L, 0x00090030L, 0x20090020L, 0x20090030L, 0x00080820L, 0x00080830L, 0x20080820L, 0x20080830L, 0x00090820L, 0x00090830L, 0x20090820L, 0x20090830L, }, { /* for C bits (numbered as per FIPS 46) 7 8 10 11 12 13 */ 0x00000000L, 0x02000000L, 0x00002000L, 0x02002000L, 0x00200000L, 0x02200000L, 0x00202000L, 0x02202000L, 0x00000004L, 0x02000004L, 0x00002004L, 0x02002004L, 0x00200004L, 0x02200004L, 0x00202004L, 0x02202004L, 0x00000400L, 0x02000400L, 0x00002400L, 0x02002400L, 0x00200400L, 0x02200400L, 0x00202400L, 0x02202400L, 0x00000404L, 0x02000404L, 0x00002404L, 0x02002404L, 0x00200404L, 0x02200404L, 0x00202404L, 0x02202404L, 0x10000000L, 0x12000000L, 0x10002000L, 0x12002000L, 0x10200000L, 0x12200000L, 0x10202000L, 0x12202000L, 0x10000004L, 0x12000004L, 0x10002004L, 0x12002004L, 0x10200004L, 0x12200004L, 0x10202004L, 0x12202004L, 0x10000400L, 0x12000400L, 0x10002400L, 0x12002400L, 0x10200400L, 0x12200400L, 0x10202400L, 0x12202400L, 0x10000404L, 0x12000404L, 0x10002404L, 0x12002404L, 0x10200404L, 0x12200404L, 0x10202404L, 0x12202404L, }, { /* for C bits (numbered as per FIPS 46) 14 15 16 17 19 20 */ 0x00000000L, 0x00000001L, 0x00040000L, 0x00040001L, 0x01000000L, 0x01000001L, 0x01040000L, 0x01040001L, 0x00000002L, 0x00000003L, 0x00040002L, 0x00040003L, 0x01000002L, 0x01000003L, 0x01040002L, 0x01040003L, 0x00000200L, 0x00000201L, 0x00040200L, 0x00040201L, 0x01000200L, 0x01000201L, 0x01040200L, 0x01040201L, 0x00000202L, 0x00000203L, 0x00040202L, 0x00040203L, 0x01000202L, 0x01000203L, 0x01040202L, 0x01040203L, 0x08000000L, 0x08000001L, 0x08040000L, 0x08040001L, 0x09000000L, 0x09000001L, 0x09040000L, 0x09040001L, 0x08000002L, 0x08000003L, 0x08040002L, 0x08040003L, 0x09000002L, 0x09000003L, 0x09040002L, 0x09040003L, 0x08000200L, 0x08000201L, 0x08040200L, 0x08040201L, 0x09000200L, 0x09000201L, 0x09040200L, 0x09040201L, 0x08000202L, 0x08000203L, 0x08040202L, 0x08040203L, 0x09000202L, 0x09000203L, 0x09040202L, 0x09040203L, }, { /* for C bits (numbered as per FIPS 46) 21 23 24 26 27 28 */ 0x00000000L, 0x00100000L, 0x00000100L, 0x00100100L, 0x00000008L, 0x00100008L, 0x00000108L, 0x00100108L, 0x00001000L, 0x00101000L, 0x00001100L, 0x00101100L, 0x00001008L, 0x00101008L, 0x00001108L, 0x00101108L, 0x04000000L, 0x04100000L, 0x04000100L, 0x04100100L, 0x04000008L, 0x04100008L, 0x04000108L, 0x04100108L, 0x04001000L, 0x04101000L, 0x04001100L, 0x04101100L, 0x04001008L, 0x04101008L, 0x04001108L, 0x04101108L, 0x00020000L, 0x00120000L, 0x00020100L, 0x00120100L, 0x00020008L, 0x00120008L, 0x00020108L, 0x00120108L, 0x00021000L, 0x00121000L, 0x00021100L, 0x00121100L, 0x00021008L, 0x00121008L, 0x00021108L, 0x00121108L, 0x04020000L, 0x04120000L, 0x04020100L, 0x04120100L, 0x04020008L, 0x04120008L, 0x04020108L, 0x04120108L, 0x04021000L, 0x04121000L, 0x04021100L, 0x04121100L, 0x04021008L, 0x04121008L, 0x04021108L, 0x04121108L, }, { /* for D bits (numbered as per FIPS 46) 1 2 3 4 5 6 */ 0x00000000L, 0x10000000L, 0x00010000L, 0x10010000L, 0x00000004L, 0x10000004L, 0x00010004L, 0x10010004L, 0x20000000L, 0x30000000L, 0x20010000L, 0x30010000L, 0x20000004L, 0x30000004L, 0x20010004L, 0x30010004L, 0x00100000L, 0x10100000L, 0x00110000L, 0x10110000L, 0x00100004L, 0x10100004L, 0x00110004L, 0x10110004L, 0x20100000L, 0x30100000L, 0x20110000L, 0x30110000L, 0x20100004L, 0x30100004L, 0x20110004L, 0x30110004L, 0x00001000L, 0x10001000L, 0x00011000L, 0x10011000L, 0x00001004L, 0x10001004L, 0x00011004L, 0x10011004L, 0x20001000L, 0x30001000L, 0x20011000L, 0x30011000L, 0x20001004L, 0x30001004L, 0x20011004L, 0x30011004L, 0x00101000L, 0x10101000L, 0x00111000L, 0x10111000L, 0x00101004L, 0x10101004L, 0x00111004L, 0x10111004L, 0x20101000L, 0x30101000L, 0x20111000L, 0x30111000L, 0x20101004L, 0x30101004L, 0x20111004L, 0x30111004L, }, { /* for D bits (numbered as per FIPS 46) 8 9 11 12 13 14 */ 0x00000000L, 0x08000000L, 0x00000008L, 0x08000008L, 0x00000400L, 0x08000400L, 0x00000408L, 0x08000408L, 0x00020000L, 0x08020000L, 0x00020008L, 0x08020008L, 0x00020400L, 0x08020400L, 0x00020408L, 0x08020408L, 0x00000001L, 0x08000001L, 0x00000009L, 0x08000009L, 0x00000401L, 0x08000401L, 0x00000409L, 0x08000409L, 0x00020001L, 0x08020001L, 0x00020009L, 0x08020009L, 0x00020401L, 0x08020401L, 0x00020409L, 0x08020409L, 0x02000000L, 0x0A000000L, 0x02000008L, 0x0A000008L, 0x02000400L, 0x0A000400L, 0x02000408L, 0x0A000408L, 0x02020000L, 0x0A020000L, 0x02020008L, 0x0A020008L, 0x02020400L, 0x0A020400L, 0x02020408L, 0x0A020408L, 0x02000001L, 0x0A000001L, 0x02000009L, 0x0A000009L, 0x02000401L, 0x0A000401L, 0x02000409L, 0x0A000409L, 0x02020001L, 0x0A020001L, 0x02020009L, 0x0A020009L, 0x02020401L, 0x0A020401L, 0x02020409L, 0x0A020409L, }, { /* for D bits (numbered as per FIPS 46) 16 17 18 19 20 21 */ 0x00000000L, 0x00000100L, 0x00080000L, 0x00080100L, 0x01000000L, 0x01000100L, 0x01080000L, 0x01080100L, 0x00000010L, 0x00000110L, 0x00080010L, 0x00080110L, 0x01000010L, 0x01000110L, 0x01080010L, 0x01080110L, 0x00200000L, 0x00200100L, 0x00280000L, 0x00280100L, 0x01200000L, 0x01200100L, 0x01280000L, 0x01280100L, 0x00200010L, 0x00200110L, 0x00280010L, 0x00280110L, 0x01200010L, 0x01200110L, 0x01280010L, 0x01280110L, 0x00000200L, 0x00000300L, 0x00080200L, 0x00080300L, 0x01000200L, 0x01000300L, 0x01080200L, 0x01080300L, 0x00000210L, 0x00000310L, 0x00080210L, 0x00080310L, 0x01000210L, 0x01000310L, 0x01080210L, 0x01080310L, 0x00200200L, 0x00200300L, 0x00280200L, 0x00280300L, 0x01200200L, 0x01200300L, 0x01280200L, 0x01280300L, 0x00200210L, 0x00200310L, 0x00280210L, 0x00280310L, 0x01200210L, 0x01200310L, 0x01280210L, 0x01280310L, }, { /* for D bits (numbered as per FIPS 46) 22 23 24 25 27 28 */ 0x00000000L, 0x04000000L, 0x00040000L, 0x04040000L, 0x00000002L, 0x04000002L, 0x00040002L, 0x04040002L, 0x00002000L, 0x04002000L, 0x00042000L, 0x04042000L, 0x00002002L, 0x04002002L, 0x00042002L, 0x04042002L, 0x00000020L, 0x04000020L, 0x00040020L, 0x04040020L, 0x00000022L, 0x04000022L, 0x00040022L, 0x04040022L, 0x00002020L, 0x04002020L, 0x00042020L, 0x04042020L, 0x00002022L, 0x04002022L, 0x00042022L, 0x04042022L, 0x00000800L, 0x04000800L, 0x00040800L, 0x04040800L, 0x00000802L, 0x04000802L, 0x00040802L, 0x04040802L, 0x00002800L, 0x04002800L, 0x00042800L, 0x04042800L, 0x00002802L, 0x04002802L, 0x00042802L, 0x04042802L, 0x00000820L, 0x04000820L, 0x00040820L, 0x04040820L, 0x00000822L, 0x04000822L, 0x00040822L, 0x04040822L, 0x00002820L, 0x04002820L, 0x00042820L, 0x04042820L, 0x00002822L, 0x04002822L, 0x00042822L, 0x04042822L, }, }; int DES_set_key(const_DES_cblock *key, DES_key_schedule *schedule) { if (DES_check_key) { return DES_set_key_checked(key, schedule); } else { DES_set_key_unchecked(key, schedule); return 0; } } LCRYPTO_ALIAS(DES_set_key); /* return 0 if key parity is odd (correct), * return -1 if key parity error, * return -2 if illegal weak key. */ int DES_set_key_checked(const_DES_cblock *key, DES_key_schedule *schedule) { if (!DES_check_key_parity(key)) return (-1); if (DES_is_weak_key(key)) return (-2); DES_set_key_unchecked(key, schedule); return 0; } LCRYPTO_ALIAS(DES_set_key_checked); void DES_set_key_unchecked(const_DES_cblock *key, DES_key_schedule *schedule) { static const int shifts2[16] = {0, 0,1, 1,1, 1,1, 1,0, 1,1, 1,1, 1,1, 0}; DES_LONG c, d, t, s, t2; const unsigned char *in; DES_LONG *k; int i; k = &schedule->ks->deslong[0]; in = &(*key)[0]; c2l(in, c); c2l(in, d); /* do PC1 in 47 simple operations :-) * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov) * for the inspiration. :-) */ PERM_OP(d, c, t, 4, 0x0f0f0f0fL); HPERM_OP(c, t, -2, 0xcccc0000L); HPERM_OP(d, t, -2, 0xcccc0000L); PERM_OP(d, c, t, 1, 0x55555555L); PERM_OP(c, d, t, 8, 0x00ff00ffL); PERM_OP(d, c, t, 1, 0x55555555L); d = (((d & 0x000000ffL) << 16L) | (d & 0x0000ff00L) | ((d & 0x00ff0000L) >> 16L)|((c & 0xf0000000L) >> 4L)); c &= 0x0fffffffL; for (i = 0; i < ITERATIONS; i++) { if (shifts2[i]) { c = ((c >> 2L)|(c << 26L)); d = ((d >> 2L)|(d << 26L)); } else { c = ((c >> 1L)|(c << 27L)); d = ((d >> 1L)|(d << 27L)); } c &= 0x0fffffffL; d &= 0x0fffffffL; /* could be a few less shifts but I am to lazy at this * point in time to investigate */ s = des_skb[0][(c)&0x3f]| des_skb[1][((c >> 6L) & 0x03)|((c >> 7L) & 0x3c)]| des_skb[2][((c >> 13L) & 0x0f)|((c >> 14L) & 0x30)]| des_skb[3][((c >> 20L) & 0x01)|((c >> 21L) & 0x06) | ((c >> 22L) & 0x38)]; t = des_skb[4][(d)&0x3f]| des_skb[5][((d >> 7L) & 0x03)|((d >> 8L) & 0x3c)]| des_skb[6][(d >> 15L) & 0x3f]| des_skb[7][((d >> 21L) & 0x0f)|((d >> 22L) & 0x30)]; /* table contained 0213 4657 */ t2 = ((t << 16L)|(s & 0x0000ffffL)) & 0xffffffffL; *(k++) = ROTATE(t2, 30) & 0xffffffffL; t2 = ((s >> 16L)|(t & 0xffff0000L)); *(k++) = ROTATE(t2, 26) & 0xffffffffL; } } LCRYPTO_ALIAS(DES_set_key_unchecked); int DES_key_sched(const_DES_cblock *key, DES_key_schedule *schedule) { return (DES_set_key(key, schedule)); } LCRYPTO_ALIAS(DES_key_sched); int DES_random_key(DES_cblock *ret) { do { arc4random_buf(ret, sizeof(DES_cblock)); DES_set_odd_parity(ret); } while (DES_is_weak_key(ret)); return (1); } LCRYPTO_ALIAS(DES_random_key); void DES_string_to_key(const char *str, DES_cblock *key) { DES_key_schedule ks; int i, length; unsigned char j; memset(key, 0, 8); length = strlen(str); #ifdef OLD_STR_TO_KEY for (i = 0; i < length; i++) (*key)[i % 8] ^= (str[i] << 1); #else /* MIT COMPATIBLE */ for (i = 0; i < length; i++) { j = str[i]; if ((i % 16) < 8) (*key)[i % 8] ^= (j << 1); else { /* Reverse the bit order 05/05/92 eay */ j = ((j << 4) & 0xf0)|((j >> 4) & 0x0f); j = ((j << 2) & 0xcc)|((j >> 2) & 0x33); j = ((j << 1) & 0xaa)|((j >> 1) & 0x55); (*key)[7 - (i % 8)] ^= j; } } #endif DES_set_odd_parity(key); #ifdef EXPERIMENTAL_STR_TO_STRONG_KEY if (DES_is_weak_key(key)) (*key)[7] ^= 0xF0; DES_set_key(key, &ks); #else DES_set_key_unchecked(key, &ks); #endif DES_cbc_cksum((const unsigned char *)str, key, length, &ks, key); explicit_bzero(&ks, sizeof(ks)); DES_set_odd_parity(key); } LCRYPTO_ALIAS(DES_string_to_key); void DES_string_to_2keys(const char *str, DES_cblock *key1, DES_cblock *key2) { DES_key_schedule ks; int i, length; unsigned char j; memset(key1, 0, 8); memset(key2, 0, 8); length = strlen(str); #ifdef OLD_STR_TO_KEY if (length <= 8) { for (i = 0; i < length; i++) { (*key2)[i] = (*key1)[i] = (str[i] << 1); } } else { for (i = 0; i < length; i++) { if ((i/8) & 1) (*key2)[i % 8] ^= (str[i] << 1); else (*key1)[i % 8] ^= (str[i] << 1); } } #else /* MIT COMPATIBLE */ for (i = 0; i < length; i++) { j = str[i]; if ((i % 32) < 16) { if ((i % 16) < 8) (*key1)[i % 8] ^= (j << 1); else (*key2)[i % 8] ^= (j << 1); } else { j = ((j << 4) & 0xf0)|((j >> 4) & 0x0f); j = ((j << 2) & 0xcc)|((j >> 2) & 0x33); j = ((j << 1) & 0xaa)|((j >> 1) & 0x55); if ((i % 16) < 8) (*key1)[7 - (i % 8)] ^= j; else (*key2)[7 - (i % 8)] ^= j; } } if (length <= 8) memcpy(key2, key1, 8); #endif DES_set_odd_parity(key1); DES_set_odd_parity(key2); #ifdef EXPERIMENTAL_STR_TO_STRONG_KEY if (DES_is_weak_key(key1)) (*key1)[7] ^= 0xF0; DES_set_key(key1, &ks); #else DES_set_key_unchecked(key1, &ks); #endif DES_cbc_cksum((const unsigned char *)str, key1, length, &ks, key1); #ifdef EXPERIMENTAL_STR_TO_STRONG_KEY if (DES_is_weak_key(key2)) (*key2)[7] ^= 0xF0; DES_set_key(key2, &ks); #else DES_set_key_unchecked(key2, &ks); #endif DES_cbc_cksum((const unsigned char *)str, key2, length, &ks, key2); explicit_bzero(&ks, sizeof(ks)); DES_set_odd_parity(key1); DES_set_odd_parity(key2); } LCRYPTO_ALIAS(DES_string_to_2keys);