crypto/ec/ec_lcl.h

   1 /* crypto/ec/ec_lcl.h */
   2 /* ====================================================================
   3  * Copyright (c) 1998-2001 The OpenSSL Project.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  *
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in
  14  *    the documentation and/or other materials provided with the
  15  *    distribution.
  16  *
  17  * 3. All advertising materials mentioning features or use of this
  18  *    software must display the following acknowledgment:
  19  *    "This product includes software developed by the OpenSSL Project
  20  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  21  *
  22  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  23  *    endorse or promote products derived from this software without
  24  *    prior written permission. For written permission, please contact
  25  *    openssl-core@openssl.org.
  26  *
  27  * 5. Products derived from this software may not be called "OpenSSL"
  28  *    nor may "OpenSSL" appear in their names without prior written
  29  *    permission of the OpenSSL Project.
  30  *
  31  * 6. Redistributions of any form whatsoever must retain the following
  32  *    acknowledgment:
  33  *    "This product includes software developed by the OpenSSL Project
  34  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  35  *
  36  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  37  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  39  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  40  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  41  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  42  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  43  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  44  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  45  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  46  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  47  * OF THE POSSIBILITY OF SUCH DAMAGE.
  48  * ====================================================================
  49  *
  50  * This product includes cryptographic software written by Eric Young
  51  * (eay@cryptsoft.com).  This product includes software written by Tim
  52  * Hudson (tjh@cryptsoft.com).
  53  *
  54  */
  55
  56
  57 #include <stdlib.h>
  58
  59 #include <openssl/ec.h>
  60
  61
  62 /* Structure details are not part of the exported interface,
  63  * so all this may change in future versions. */
  64
  65 struct ec_method_st {
  66         /* used by EC_GROUP_new, EC_GROUP_set_curve_GFp, EC_GROUP_free, EC_GROUP_copy: */
  67         int (*group_init)(EC_GROUP *);
  68         /* int (*group_set)(EC_GROUP *, .....); */
  69         int (*group_set_curve_GFp)(EC_GROUP *, const BIGNUM *p, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
  70         void (*group_finish)(EC_GROUP *);
  71         void (*group_clear_finish)(EC_GROUP *);
  72         int (*group_copy)(EC_GROUP *, const EC_GROUP *);
  73
  74         /* used by EC_GROUP_set_generator: */
  75         int (*group_set_generator)(EC_GROUP *, const EC_POINT *generator,
  76                 const BIGNUM *order, const BIGNUM *cofactor);
  77
  78         /* TODO: 'set' and 'get' functions for EC_GROUPs */
  79
  80
  81         /* used by EC_POINT_new, EC_POINT_free, EC_POINT_copy: */
  82         int (*point_init)(EC_POINT *);
  83         void (*point_finish)(EC_POINT *);
  84         void (*point_clear_finish)(EC_POINT *);
  85         int (*point_copy)(EC_POINT *, const EC_POINT *);
  86
  87         int (*point_set_to_infinity)(const EC_GROUP *, EC_POINT *);
  88         int (*point_set_affine_coordinates_GFp)(const EC_GROUP *, EC_POINT *,
  89                 const BIGNUM *x, const BIGNUM *y, BN_CTX *);
  90         int (*point_get_affine_coordinates_GFp)(const EC_GROUP *, const EC_POINT *,
  91                 BIGNUM *x, BIGNUM *y, BN_CTX *);
  92         /* TODO: other 'set' and 'get' functions for EC_POINTs */
  93
  94         /* used by EC_POINT_point2oct, EC_POINT_oct2point: */
  95         size_t (*point2oct)(const EC_GROUP *, const EC_POINT *, point_conversion_form_t form,
  96                 unsigned char *buf, size_t len, BN_CTX *);
  97         int (*oct2point)(const EC_GROUP *, EC_POINT *,
  98                 const unsigned char *buf, size_t len, BN_CTX *);
  99
 100         /* used by EC_POINT_add, EC_POINT_dbl: */
 101         int (*add)(const EC_GROUP *, EC_POINT *r, const EC_POINT *a, const EC_POINT *b, BN_CTX *);
 102         int (*dbl)(const EC_GROUP *, EC_POINT *r, const EC_POINT *a, BN_CTX *);
 103
 104         /* used by EC_POINT_is_at_infinity, EC_POINT_is_on_curve, EC_POINT_make_affine */
 105         int (*is_at_infinity)(const EC_GROUP *, const EC_POINT *);
 106         int (*is_on_curve)(const EC_GROUP *, const EC_POINT *, BN_CTX *);
 107         int (*make_affine)(const EC_GROUP *, EC_POINT *, BN_CTX *);
 108
 109
 110         /* internal functions */
 111
 112         /* 'field_mul' and 'field_sqr' can be used by 'add' and 'dbl' so that
 113          * the same implementations of point operations can be used with different
 114          * optimized implementations of expensive field operations: */
 115         int (*field_mul)(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
 116         int (*field_sqr)(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
 117
 118         int (*field_encode)(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *); /* e.g. to Montgomery */
 119         int (*field_decode)(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *); /* e.g. from Montgomery */
 120 } /* EC_METHOD */;
 121
 122
 123 struct ec_group_st {
 124         const EC_METHOD *meth;
 125
 126         void *extra_data;
 127         void *(*extra_data_dup_func)(void *);
 128         void (*extra_data_free_func)(void *);
 129         void (*extra_data_clear_free_func)(void *);
 130
 131         /* All members except 'meth' and 'extra_data...' are handled by
 132          * the method functions, even if they appear generic */
 133
 134         BIGNUM field; /* Field specification.
 135                        * For curves over GF(p), this is the modulus. */
 136
 137         BIGNUM a, b; /* Curve coefficients.
 138                       * (Here the assumption is that BIGNUMs can be used
 139                       * or abused for all kinds of fields, not just GF(p).)
 140                       * For characteristic  > 3,  the curve is defined
 141                       * by a Weierstrass equation of the form
 142                       *     y^2 = x^3 + a*x + b.
 143                       */
 144         int a_is_minus3; /* enable optimized point arithmetics for special case */
 145
 146         EC_POINT *generator; /* optional */
 147         BIGNUM order, cofactor;
 148
 149         void *field_data; /* method-specific (e.g., Montgomery structure) */
 150 } /* EC_GROUP */;
 151
 152
 153 /* Basically a 'mixin' for extra data, but available for EC_GROUPs only
 154  * (with visibility limited to 'package' level for now).
 155  * We use the function pointers as index for retrieval; this obviates
 156  * global ex_data-style index tables.
 157  * (Currently, we have one slot only, but is is possible to extend this
 158  * if necessary.) */
 159 int EC_GROUP_set_extra_data(EC_GROUP *, void *extra_data, void *(*extra_data_dup_func)(void *),
 160         void (*extra_data_free_func)(void *), void (*extra_data_clear_free_func)(void *));
 161 void *EC_GROUP_get_extra_data(EC_GROUP *, void *(*extra_data_dup_func)(void *),
 162         void (*extra_data_free_func)(void *), void (*extra_data_clear_free_func)(void *));
 163 void EC_GROUP_free_extra_data(EC_GROUP *);
 164 void EC_GROUP_clear_free_extra_data(EC_GROUP *);
 165
 166
 167
 168 struct ec_point_st {
 169         const EC_METHOD *meth;
 170
 171         /* All members except 'meth' are handled by the method functions,
 172          * even if they appear generic */
 173
 174         BIGNUM X;
 175         BIGNUM Y;
 176         BIGNUM Z; /* Jacobian projective coordinates:
 177                    * (X, Y, Z)  represents  (X/Z^2, Y/Z^3)  if  Z != 0 */
 178         int Z_is_one; /* enable optimized point arithmetics for special case */
 179 } /* EC_POINT */;
 180
 181
 182
 183 /* method functions in ecp_smpl.c */
 184 int ec_GFp_simple_group_init(EC_GROUP *);
 185 int ec_GFp_simple_group_set_curve_GFp(EC_GROUP *, const BIGNUM *p, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
 186 void ec_GFp_simple_group_finish(EC_GROUP *);
 187 void ec_GFp_simple_group_clear_finish(EC_GROUP *);
 188 int ec_GFp_simple_group_copy(EC_GROUP *, const EC_GROUP *);
 189 int ec_GFp_simple_group_set_generator(EC_GROUP *, const EC_POINT *generator,
 190         const BIGNUM *order, const BIGNUM *cofactor);
 191 /* TODO: 'set' and 'get' functions for EC_GROUPs */
 192 int ec_GFp_simple_point_init(EC_POINT *);
 193 void ec_GFp_simple_point_finish(EC_POINT *);
 194 void ec_GFp_simple_point_clear_finish(EC_POINT *);
 195 int ec_GFp_simple_point_copy(EC_POINT *, const EC_POINT *);
 196 int ec_GFp_simple_point_set_to_infinity(const EC_GROUP *, EC_POINT *);
 197 int ec_GFp_simple_point_set_affine_coordinates_GFp(const EC_GROUP *, EC_POINT *,
 198         const BIGNUM *x, const BIGNUM *y, BN_CTX *);
 199 int ec_GFp_simple_point_get_affine_coordinates_GFp(const EC_GROUP *, const EC_POINT *,
 200         BIGNUM *x, BIGNUM *y, BN_CTX *);
 201 /* TODO: other 'set' and 'get' functions for EC_POINTs */
 202 size_t ec_GFp_simple_point2oct(const EC_GROUP *, const EC_POINT *, point_conversion_form_t form,
 203         unsigned char *buf, size_t len, BN_CTX *);
 204 int ec_GFp_simple_oct2point(const EC_GROUP *, EC_POINT *,
 205         const unsigned char *buf, size_t len, BN_CTX *);
 206 int ec_GFp_simple_add(const EC_GROUP *, EC_POINT *r, const EC_POINT *a, const EC_POINT *b, BN_CTX *);
 207 int ec_GFp_simple_dbl(const EC_GROUP *, EC_POINT *r, const EC_POINT *a, BN_CTX *);
 208 int ec_GFp_simple_is_at_infinity(const EC_GROUP *, const EC_POINT *);
 209 int ec_GFp_simple_is_on_curve(const EC_GROUP *, const EC_POINT *, BN_CTX *);
 210 int ec_GFp_simple_make_affine(const EC_GROUP *, EC_POINT *, BN_CTX *);
 211 int ec_GFp_simple_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
 212 int ec_GFp_simple_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
 213
 214
 215 /* method functions in ecp_mont.c */
 216 int ec_GFp_mont_group_init(EC_GROUP *);
 217 int ec_GFp_mont_group_set_curve_GFp(EC_GROUP *, const BIGNUM *p, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
 218 void ec_GFp_mont_group_finish(EC_GROUP *);
 219 void ec_GFp_mont_group_clear_finish(EC_GROUP *);
 220 int ec_GFp_mont_group_copy(EC_GROUP *, const EC_GROUP *);
 221 int ec_GFp_mont_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
 222 int ec_GFp_mont_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
 223 int ec_GFp_mont_field_encode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
 224 int ec_GFp_mont_field_decode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
 225
 226
 227 /* method functions in ecp_recp.c */
 228 int ec_GFp_recp_group_init(EC_GROUP *);
 229 int ec_GFp_recp_group_set_curve_GFp(EC_GROUP *, const BIGNUM *p, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
 230 void ec_GFp_recp_group_finish(EC_GROUP *);
 231 void ec_GFp_recp_group_clear_finish(EC_GROUP *);
 232 int ec_GFp_recp_group_copy(EC_GROUP *, const EC_GROUP *);
 233 int ec_GFp_recp_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
 234 int ec_GFp_recp_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
 235 int ec_GFp_recp_field_encode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
 236 int ec_GFp_recp_field_decode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
 237
 238
 239 /* method functions in ecp_nist.c */
 240 int ec_GFp_nist_group_init(EC_GROUP *);
 241 int ec_GFp_nist_group_set_curve_GFp(EC_GROUP *, const BIGNUM *p, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
 242 void ec_GFp_nist_group_finish(EC_GROUP *);
 243 void ec_GFp_nist_group_clear_finish(EC_GROUP *);
 244 int ec_GFp_nist_group_copy(EC_GROUP *, const EC_GROUP *);
 245 int ec_GFp_nist_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
 246 int ec_GFp_nist_field_sqr(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
 247 int ec_GFp_nist_field_encode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
 248 int ec_GFp_nist_field_decode(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);