/* * des - fast & portable DES encryption & decryption. * Copyright (C) 1992 Dana L. How * Please see the file `descore.README' for the complete copyright notice. * * Slightly edited by Niels Möller, 1997 */ #include "des.h" #include "RCSID.h" RCSID2(desQuick_cRcs, "$Id$"); extern UINT32 des_keymap[]; /* static information */ static int depth = 0; /* keep track of the request depth */ UINT32 des_bigmap[0x4000]; /* big lookup table */ /* fill in the 64k table used by the `quick' option */ void DesQuickInit(void) { int s1, s3, x; UINT32 * t0, * t1, * t2, * t3; if ( depth++ ) return; t0 = des_bigmap; t1 = t0 + 64; t2 = t1 + 64; t3 = t2 + 64; for ( s3 = 63; s3 >= 0; s3-- ) { for ( s1 = 63; s1 >= 0; s1-- ) { x = (s3 << 8) | s1; t0[x] = des_keymap[s3+128] ^ des_keymap[s1+192]; t1[x] = des_keymap[s3 ] ^ des_keymap[s1+ 64]; t2[x] = des_keymap[s3+384] ^ des_keymap[s1+448]; t3[x] = des_keymap[s3+256] ^ des_keymap[s1+320]; } } } /* free the 64k table, if necessary */ void DesQuickDone(void) { }