/* $OpenBSD: set_key.c,v 1.6 2025/10/27 16:56:00 tb Exp $ */ /* lib/des/set_key.c */ /* Copyright (C) 1995 Eric Young (eay@mincom.oz.au) * All rights reserved. * * This file is part of an SSL implementation written * by Eric Young (eay@mincom.oz.au). * The implementation was written so as to conform with Netscapes SSL * specification. This library and applications are * FREE FOR COMMERCIAL AND NON-COMMERCIAL USE * as long as the following conditions are aheared to. * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. If this code is used in a product, * Eric Young should be given attribution as the author of the parts 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 software developed by Eric Young (eay@mincom.oz.au) * * 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.] */ /* set_key.c v 1.4 eay 24/9/91 * 1.4 Speed up by 400% :-) * 1.3 added register declarations. * 1.2 unrolled make_key_sched a bit more * 1.1 added norm_expand_bits * 1.0 First working version */ #include "des_locl.h" #include "podd.h" #include "sk.h" static int check_parity(des_cblock (*key)); int des_check_key=0; static int check_parity(des_cblock (*key)) { int i; for (i = 0; i < DES_KEY_SZ; i++) { if ((*key)[i] != odd_parity[(*key)[i]]) return(0); } return (1); } /* 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 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(des_cblock (*key)) { int i; for (i = 0; i < NUM_WEAK_KEY; i++) { /* Added == 0 to comparison, I obviously don't run * this section very often :-(, thanks to * engineering@MorningStar.Com for the fix * eay 93/06/29 */ if (bcmp(weak_keys[i], key, sizeof(des_cblock)) == 0) return (1); } return (0); } /* 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 int shifts2[16]={0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0}; /* return 0 if key parity is odd (correct), * return -1 if key parity error, * return -2 if illegal weak key. */ int des_set_key(des_cblock (*key), des_key_schedule schedule) { register u_int32_t c, d, t, s; register unsigned char *in; register u_int32_t *k; register int i; if (des_check_key) { if (!check_parity(key)) return(-1); if (des_is_weak_key(key)) return(-2); } k = (u_int32_t *) schedule; in = (unsigned char *) key; c2l(in, c); c2l(in, d); /* do PC1 in 60 simple operations */ /* PERM_OP(d, c, t, 4, 0x0f0f0f0fL); HPERM_OP(c, t, -2, 0xcccc0000L); HPERM_OP(c, t, -1, 0xaaaa0000L); HPERM_OP(c, t, 8, 0x00ff0000L); HPERM_OP(c, t, -1, 0xaaaa0000L); HPERM_OP(d, t, -8, 0xff000000L); HPERM_OP(d, t, 8, 0x00ff0000L); HPERM_OP(d, t, 2, 0x33330000L); d = ((d & 0x00aa00aaL) << 7L) | ((d & 0x55005500L) >> 7L) | (d & 0xaa55aa55L); d = (d >> 8) | ((c & 0xf0000000L) >> 4); c &= 0x0fffffffL; */ /* I now do it 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 >> 6) & 0x03) | ((c >> 7L) & 0x3c)]| des_skb[2][((c >> 13) & 0x0f) | ((c >> 14L) & 0x30)]| des_skb[3][((c >> 20) & 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 */ *(k++) = ((t << 16L) | (s & 0x0000ffffL)) & 0xffffffffL; s = ((s >> 16L) | (t & 0xffff0000L)); s = (s << 4L) | (s >> 28L); *(k++) = s & 0xffffffffL; } return (0); }
