X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/fcdaa1806c38c703a6e72b87e189396a05d165e4..4739c68a6cb81cae53cd7df694ecd6176d6f11f8:/prim.h diff --git a/prim.h b/prim.h index 30392cd..193d058 100644 --- a/prim.h +++ b/prim.h @@ -1,6 +1,6 @@ /* -*-c-*- * - * $Id: prim.h,v 1.1 1999/12/22 15:58:59 mdw Exp $ + * $Id: prim.h,v 1.3 2004/04/08 01:36:15 mdw Exp $ * * Finding primitive elements * @@ -27,14 +27,6 @@ * MA 02111-1307, USA. */ -/*----- Revision history --------------------------------------------------* - * - * $Log: prim.h,v $ - * Revision 1.1 1999/12/22 15:58:59 mdw - * Search for primitive elements using prime-search equipment. - * - */ - #ifndef CATACOMB_PRIM_H #define CATACOMB_PRIM_H @@ -64,12 +56,20 @@ * * All fields must be configured by the client. Set @n@ to zero to discover * generators of the subgroup of order %$m / f$%. + * + * Let %$p = \prod q_i + 1$% be a prime number. In order to find an element + * %$g$% with order %$o$%, we choose elements %$h_j$% from %$\gf{p}^*$%, + * compute $%g_j = h_j^{p/o}$%, rejecting %$h_j$% where %$g_j = 1$%, and then + * for each proper prime factor %$q_i$% of %$p/o$% we check that + * %$g^{f_i} \ne 1$%, where the %$f_i$% are cofactors of the %$q_i$% + * (%$f_i q_i = p/o$%). */ typedef struct prim_ctx { mpmont mm; /* Montgomery context for modulus */ - mp *f; /* Array of factors */ - size_t n; /* Number of factors */ + mp *exp; /* Exponent (%$p/o$%; may be zero) */ + size_t n; /* Number of cofactors */ + mp **f; /* Array of cofactors */ } prim_ctx; /*----- Functions provided ------------------------------------------------*/