X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/b817bfc642225b8c3c0b6a7e42d1fb949b61a606..c3321b13915e3b839da060f8dc63c68e31bcc360:/bbs.h diff --git a/bbs.h b/bbs.h index 7c9cbda..30fb474 100644 --- a/bbs.h +++ b/bbs.h @@ -1,13 +1,13 @@ /* -*-c-*- * - * $Id: bbs.h,v 1.7 2004/04/08 01:36:15 mdw Exp $ + * $Id$ * * The Blum-Blum-Shub random bit generator * * (c) 1999 Straylight/Edgeware */ -/*----- Licensing notice --------------------------------------------------* +/*----- Licensing notice --------------------------------------------------* * * This file is part of Catacomb. * @@ -15,12 +15,12 @@ * it under the terms of the GNU Library General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. - * + * * Catacomb is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Library General Public License for more details. - * + * * You should have received a copy of the GNU Library General Public * License along with Catacomb; if not, write to the Free * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, @@ -213,35 +213,25 @@ extern void bbs_wrap(bbs */*b*/); /*----- Large forwards and backwards jumps --------------------------------*/ -/* --- @bbs_ff@ --- * - * - * Arguments: @bbs *b@ = pointer to a BBS generator state - * @bbs_priv *bp@ = pointer to BBS modulus factors - * @unsigned long n@ = number of steps to make - * - * Returns: --- - * - * Use: `Fast-forwards' a Blum-Blum-Shub generator by @n@ steps. - * Requires the factorization of the Blum modulus to do this - * efficiently. - */ - -extern void bbs_ff(bbs */*b*/, bbs_priv */*bp*/, unsigned long /*n*/); - -/* --- @bbs_rew@ --- * +/* --- @bbs_{ff,rew}{,n}@ --- * * * Arguments: @bbs *b@ = pointer to a BBS generator state - * @bbs_priv *bp@ = pointer to BBS modulus factors - * @unsigned long n@ = number of steps to make + * @const bbs_priv *bp@ = pointer to BBS modulus factors + * @mp *n@, @unsigned long n@ = number of steps to make * * Returns: --- * - * Use: `Rewinds' a Blum-Blum-Shub generator by @n@ steps. - * Requires the factorization of the Blum modulus to do this - * at all. + * Use: `Fast-forwards' or rewinds a Blum-Blum-Shub generator by @n@ + * steps. The @...n@ versions take an @unsigned long@ argument; + * the non-@...n@ versions a multiprecision integer. If @n@ is + * negative then the generator is stepped in the reverse + * direction. */ -extern void bbs_rew(bbs */*b*/, bbs_priv */*bp*/, unsigned long /*n*/); +extern void bbs_ff(bbs */*b*/, const bbs_priv */*bp*/, mp */*n*/); +extern void bbs_ffn(bbs */*b*/, const bbs_priv */*bp*/, unsigned long /*n*/); +extern void bbs_rew(bbs */*b*/, const bbs_priv */*bp*/, mp */*n*/); +extern void bbs_rewn(bbs */*b*/, const bbs_priv */*bp*/, unsigned long /*n*/); /*----- Parameter generation ----------------------------------------------*/ @@ -257,7 +247,7 @@ extern void bbs_rew(bbs */*b*/, bbs_priv */*bp*/, unsigned long /*n*/); * Returns: If it worked OK, @PGEN_DONE@, otherwise @PGEN_ABORT@. * * Use: Finds two prime numbers %$p'$% and %$q'$% such that both are - * congruent to %$3 \bmod 4$%, and $(p - 1)/2$% and + * congruent to %$3 \bmod 4$%, and $(p - 1)/2$% and * %$(q - 1)/2$% have no common factors. The product %$n = pq$% * is eminently suitable for use as a modulus in a Blum-Blum- * Shub pseudorandom bit generator. @@ -270,12 +260,12 @@ extern int bbs_gen(bbs_priv */*bp*/, unsigned /*nbits*/, grand */*r*/, /* --- @bbs_rand@ --- * * - * Arguments: @mp *m@ = modulus + * Arguments: @mp *m@ = modulus * @mp *x@ = initial seed * - * Returns: Pointer to a generic generator. + * Returns: Pointer to a generic generator. * - * Use: Constructs a generic generator interface over a + * Use: Constructs a generic generator interface over a * Blum-Blum-Shub generator. */ @@ -284,7 +274,17 @@ extern grand *bbs_rand(mp */*m*/, mp */*x*/); /* --- Blum-Blum-Shub-specific misc op codes --- */ enum { - BBS_SET = GRAND_SPECIFIC('B') /* @mp *x@ */ + BBS_SET = GRAND_SPECIFIC('B'), /* @mp *x@ */ + BBS_STEP, /* @void@ */ + BBS_STEPSZ, /* @void@ */ + BBS_BITS, /* @unsigned bits, uint32 *w@ */ + BBS_WRAP, /* @void@ */ + BBS_FF, /* @bbs_priv *p, mp *n@ */ + BBS_FFN, /* @bbs_priv *p, unsigned long n@ */ + BBS_REW, /* @bbs_priv *p, mp *n@ */ + BBS_REWN, /* @bbs_priv *p, unsigned long n@ */ + BBS_MOD, /* @mp **n@ */ + BBS_STATE /* @mp **x@ */ }; /*----- That's all, folks -------------------------------------------------*/