+++ /dev/null
-/* -*-c-*-
- *
- * $Id$
- *
- * General cyclic group abstraction
- *
- * (c) 2004 Straylight/Edgeware
- */
-
-/*----- Licensing notice --------------------------------------------------*
- *
- * This file is part of Catacomb.
- *
- * Catacomb is free software; you can redistribute it and/or modify
- * 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,
- * MA 02111-1307, USA.
- */
-
-#ifndef CATACOMB_GROUP_H
-#define CATACOMB_GROUP_H
-
-#ifdef __cplusplus
- extern "C" {
-#endif
-
-/*----- Header files ------------------------------------------------------*/
-
-#include <mLib/dstr.h>
-
-#ifndef CATACOMB_BUF_H
-# include "buf.h"
-#endif
-
-#ifndef CATACOMB_DH_H
-# include "ec.h"
-#endif
-
-#ifndef CATACOMB_GRAND_H
-# include "grand.h"
-#endif
-
-#ifndef CATACOMB_MP_H
-# include "mp.h"
-#endif
-
-#ifndef CATACOMB_QDPARSE_H
-# include "qdparse.h"
-#endif
-
-/*----- Data structures ---------------------------------------------------*/
-
-#ifndef ge
- typedef struct ge ge; /* Group element (abstract type) */
-#endif
-
-typedef struct group_ {
- const struct group_ops *ops; /* Operations table */
- size_t nbits; /* Size of an element in bits */
- size_t noctets; /* Size of raw element in octets */
- ge *i; /* Identity element */
- ge *g; /* Generator element */
- mp *r; /* Order of the generator */
- mp *h; /* Cofactor */
-} group;
-
-typedef struct group_expfactor {
- ge *base; /* The base */
- mp *exp; /* The exponent */
-} group_expfactor;
-
-typedef struct group_ops {
-
- /* --- General information --- */
-
- unsigned ty; /* Type of this group */
- const char *name; /* Textual name string */
-
- /* --- Memory management --- */
-
- void (*destroygroup)(group */*g*/);
- ge *(*create)(group */*g*/);
- void (*copy)(group */*g*/, ge */*d*/, ge */*x*/);
- void (*burn)(group */*g*/, ge */*x*/);
- void (*destroy)(group */*g*/, ge */*e*/);
-
- /* --- Comparisons --- */
-
- int (*samep)(group */*g*/, group */*h*/);
- int (*eq)(group */*g*/, ge */*x*/, ge */*y*/);
- int (*identp)(group */*g*/, ge */*x*/);
-
- /* --- Other stuff --- */
-
- const char *(*check)(group */*g*/, grand */*gr*/);
-
- /* --- Arithmetic --- */
-
- void (*mul)(group */*g*/, ge */*d*/, ge */*x*/, ge */*y*/);
- void (*sqr)(group */*g*/, ge */*d*/, ge */*x*/);
- void (*inv)(group */*g*/, ge */*d*/, ge */*x*/);
- void (*div)(group */*g*/, ge */*d*/, ge */*x*/, ge */*y*/);
- void (*exp)(group */*g*/, ge */*d*/, ge */*x*/, mp */*n*/);
- void (*mexp)(group */*g*/, ge */*d*/,
- const group_expfactor */*f*/, size_t /*n*/);
-
- /* --- Debugging --- */
-
- int (*read)(group */*g*/, ge */*d*/,
- const mptext_ops */*ops*/, void */*p*/);
- int (*write)(group */*g*/, ge */*x*/,
- const mptext_ops */*ops*/, void */*p*/);
-
- /* --- Conversions --- */
-
- mp *(*toint)(group */*g*/, mp */*d*/, ge */*x*/);
- int (*fromint)(group */*g*/, ge */*d*/, mp */*x*/);
- int (*toec)(group */*g*/, ec */*d*/, ge */*x*/);
- int (*fromec)(group */*g*/, ge */*d*/, const ec */*p*/);
- int (*tobuf)(group */*h*/, buf */*b*/, ge */*x*/);
- int (*frombuf)(group */*h*/, buf */*b*/, ge */*d*/);
- int (*toraw)(group */*h*/, buf */*b*/, ge */*x*/);
- int (*fromraw)(group */*h*/, buf */*b*/, ge */*d*/);
-
-} group_ops;
-
-enum {
- GTY_PRIME, /* Prime field subgroup */
- GTY_BINARY, /* Binary feld subgroup */
- GTY_EC /* Elliptic curve group */
-};
-
-#define G_NAME(g) (g)->ops->name
-#define G_TYPE(g) (g)->ops->ty
-
-#define G_DESTROYGROUP(g) (g)->ops->destroygroup((g))
-#define G_CREATE(g) (g)->ops->create((g))
-#define G_COPY(g, d, x) (g)->ops->copy((g), (d), (x))
-#define G_BURN(g, x) (g)->ops->burn((g), (x))
-#define G_DESTROY(g, x) (g)->ops->destroy((g), (x))
-
-#define G_SAMEP(g, h) (g)->ops->samep((g), (h))
-#define G_EQ(g, x, y) (g)->ops->eq((g), (x), (y))
-#define G_IDENTP(g, x) (g)->ops->identp((g), (x))
-
-#define G_CHECK(g, gr) (g)->ops->check((g), (gr))
-
-#define G_MUL(g, d, x, y) (g)->ops->mul((g), (d), (x), (y))
-#define G_SQR(g, d, x) (g)->ops->sqr((g), (d), (x))
-#define G_INV(g, d, x) (g)->ops->inv((g), (d), (x))
-#define G_DIV(g, d, x, y) (g)->ops->div((g), (d), (x), (y))
-#define G_EXP(g, d, x, n) (g)->ops->exp((g), (d), (x), (n))
-#define G_MEXP(g, d, f, n) (g)->ops->mexp((g), (d), (f), (n))
-
-#define G_READ(g, d, o, p) (g)->ops->read((g), (d), (o), (p))
-#define G_WRITE(g, x, o, p) (g)->ops->write((g), (x), (o), (p))
-
-#define G_TOINT(g, d, x) (g)->ops->toint((g), (d), (x))
-#define G_FROMINT(g, d, x) (g)->ops->fromint((g), (d), (x))
-#define G_TOEC(g, d, x) (g)->ops->toec((g), (d), (x))
-#define G_FROMEC(g, d, p) (g)->ops->fromec((g), (d), (p))
-#define G_TOBUF(g, b, x) (g)->ops->tobuf((g), (b), (x))
-#define G_FROMBUF(g, b, d) (g)->ops->frombuf((g), (b), (d))
-#define G_TORAW(g, b, x) (g)->ops->toraw((g), (b), (x))
-#define G_FROMRAW(g, b, d) (g)->ops->fromraw((g), (b), (d))
-
-/*----- Handy functions ---------------------------------------------------*/
-
-/* --- @group_check@ --- *
- *
- * Arguments: @group *g@ = an abstract group
- * @ge *x@ = a group element
- *
- * Returns: Zero on success, nonzero for failure.
- *
- * Use: Checks that @x@ is a valid group element. This may take a
- * while, since it checks that %$x^h \ne 1$%.
- */
-
-extern int group_check(group */*g*/, ge */*x*/);
-
-/* --- @group_samep@ --- *
- *
- * Arguments: @group *g, *h@ = two abstract groups
- *
- * Returns: Nonzero if the groups are in fact identical (not just
- * isomorphic).
- *
- * Use: Checks to see whether two groups are actually the same. This
- * function does the full check: the group operatrion @samep@
- * just does the group-specific details.
- */
-
-extern int group_samep(group */*g*/, group */*h*/);
-
-/*----- Textual I/O on group elements -------------------------------------*/
-
-extern int group_readstring(group */*g*/, ge */*d*/,
- const char */*p*/, char **/*end*/);
-extern int group_writestring(group */*g*/, ge */*d*/,
- char */*p*/, size_t /*sz*/);
-
-extern int group_readfile(group */*g*/, ge */*d*/, FILE */*fp*/);
-extern int group_writefile(group */*g*/, ge */*x*/, FILE */*fp*/);
-
-extern int group_readdstr(group */*g*/, ge */*d*/,
- dstr */*dd*/, size_t */*off*/);
-extern int group_writedstr(group */*g*/, ge */*x*/, dstr */*d*/);
-
-/*----- Standard implementations ------------------------------------------*/
-
-/* --- @group_stdidentp@ --- *
- *
- * Arguments: @group *g@ = abstract group
- * @ge *x@ = group element
- *
- * Returns: Nonzero if %$x$% is the group identity.
- */
-
-extern int group_stdidentp(group */*g*/, ge */*x*/);
-
-/* --- @group_stdcheck@ --- *
- *
- * Arguments: @group *g@ = abstract group
- * @grand *gr@ = random number source.
- *
- * Returns: Null on success, or a pointer to an error message.
- */
-
-extern const char *group_stdcheck(group */*g*/, grand */*gr*/);
-
-/* --- @group_stdsqr@ --- *
- *
- * Arguments: @group *g@ = abstract group
- * @ge *d@ = destination pointer
- * @ge *x@ = group element
- *
- * Returns: ---
- *
- * Use: Computes %$d = x^2$% as %$d = x x$%.
- */
-
-extern void group_stdsqr(group */*g*/, ge */*d*/, ge */*x*/);
-
-/* --- @group_stddiv@ --- *
- *
- * Arguments: @group *g@ = abstract group
- * @ge *d@ = destination pointer
- * @ge *x@ = dividend
- * @ge *y@ = divisor
- *
- * Returns: ---
- *
- * Use: Computes %$d = x/y$% as %$d = x y^{-1}$%.
- */
-
-extern void group_stddiv(group */*g*/, ge */*d*/, ge */*x*/, ge */*y*/);
-
-/* --- @group_stdexp@ --- *
- *
- * Arguments: @group *g@ = abstract group
- * @ge *d@ = destination pointer
- * @ge *x@ = base element
- * @mp *n@ = exponent
- *
- * Returns: ---
- *
- * Use: Computes %$d = x^n$% efficiently.
- */
-
-extern void group_stdexp(group */*g*/, ge */*d*/, ge */*x*/, mp */*n*/);
-
-/* --- @group_stdmexp@ --- *
- *
- * Arguments: @group *g@ = abstract group
- * @ge *d@ = destination pointer
- * @const group_expfactor *f@ = vector of factors
- * @size_t n@ = number of factors
- *
- * Returns: ---
- *
- * Use: Computes %$d = g_0^{x_0} g_1^{x_1} \ldots$% efficiently.
- */
-
-extern void group_stdmexp(group */*g*/, ge */*d*/,
- const group_expfactor */*f*/, size_t /*n*/);
-
-/* --- @group_stdtoec@ --- *
- *
- * Arguments: @group *g@ = abstract group
- * @ec *d@ = destination point
- * @ge *x@ = group element
- *
- * Returns: @-1@, indicating failure.
- *
- * Use: Fails to convert a group element to an elliptic curve point.
- */
-
-extern int group_stdtoec(group */*g*/, ec */*d*/, ge */*x*/);
-
-/* --- @group_stdfromec@ --- *
- *
- * Arguments: @group *g@ = abstract group
- * @ge *d@ = destination pointer
- * @const ec *p@ = elliptic curve point
- *
- * Returns: Zero for success, @-1@ on failure.
- *
- * Use: Converts %$p$% to a group element by converting its %$x$%-
- * coordinate.
- */
-
-extern int group_stdfromec(group */*g*/, ge */*d*/, const ec */*p*/);
-
-/*----- Prime field subgroups ---------------------------------------------*/
-
-typedef struct gprime_param {
- mp *p, *q; /* Prime numbers %$p$% and %$q$% */
- mp *g; /* Generates order-%$q$% subgroup */
-} gprime_param;
-
-/* --- @group_prime@ --- *
- *
- * Arguments: @const gprime_param *gp@ = group parameters
- *
- * Returns: A pointer to the group, or null.
- *
- * Use: Constructs an abstract group interface for a subgroup of a
- * prime field. Group elements are @mp *@ pointers.
- */
-
-group *group_prime(const gprime_param */*gp*/);
-
-/*----- Binary field subgroups --------------------------------------------*/
-
-typedef gprime_param gbin_param;
-
-/* --- @group_binary@ --- *
- *
- * Arguments: @const gbin_param *gb@ = group parameters
- *
- * Returns: A pointer to the group, or null.
- *
- * Use: Constructs an abstract group interface for a subgroup of a
- * prime field. Group elements are @mp *@ pointers.
- */
-
-group *group_binary(const gbin_param */*gp*/);
-
-/*----- Elliptic curve groups ---------------------------------------------*/
-
-/* --- @group_ec@ --- *
- *
- * Arguments: @const ec_info *ei@ = elliptic curve parameters
- *
- * Returns: A pointer to the group, or null.
- *
- * Use: Constructs an abstract group interface for an elliptic curve
- * group. Group elements are @ec@ structures. The contents of
- * the @ec_info@ structure becomes the property of the @group@
- * object; you can (and should) free the structure itself, but
- * calling @ec_freeinfo@ on it is not allowed.
- */
-
-group *group_ec(const ec_info */*ei*/);
-
-/*----- General group initialization --------------------------------------*/
-
-/* --- @group_parse@ --- *
- *
- * Arguments: @qd_parse *qd@ = quick-and-dirty parser
- *
- * Returns: Group pointer, or null for failure.
- *
- * Use: Parses a group description and returns the group. This has
- * the form `TYPE { SPEC }' where TYPE is `prime' or `ec', and
- * SPEC is the appropriate kind of group specification of the
- * given type.
- */
-
-extern group *group_parse(qd_parse */*qd*/);
-
-/* --- @group_fromstring@ --- *
- *
- * Arguments: @const char *p@ = pointer to string to read
- * @group **gg@ = where to put the group pointer
- *
- * Returns: Null if OK, or an error string.
- *
- * Use: Parses a group spec from a string, and returns the group.
- */
-
-extern const char *group_fromstring(const char */*p*/, group **/*gg*/);
-
-/*----- That's all, folks -------------------------------------------------*/
-
-#ifdef __cplusplus
- }
-#endif
-
-#endif
projects / u / mdw / catacomb / blobdiff