2 /* crypto/ec/ec_lcl.h */
3 /* ====================================================================
4 * Copyright (c) 1998-2001 The OpenSSL Project. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
18 * 3. All advertising materials mentioning features or use of this
19 * software must display the following acknowledgment:
20 * "This product includes software developed by the OpenSSL Project
21 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
23 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
24 * endorse or promote products derived from this software without
25 * prior written permission. For written permission, please contact
26 * openssl-core@openssl.org.
28 * 5. Products derived from this software may not be called "OpenSSL"
29 * nor may "OpenSSL" appear in their names without prior written
30 * permission of the OpenSSL Project.
32 * 6. Redistributions of any form whatsoever must retain the following
34 * "This product includes software developed by the OpenSSL Project
35 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
37 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
38 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
39 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
40 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
41 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
42 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
43 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
44 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
45 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
46 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
47 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
48 * OF THE POSSIBILITY OF SUCH DAMAGE.
49 * ====================================================================
51 * This product includes cryptographic software written by Eric Young
52 * (eay@cryptsoft.com). This product includes software written by Tim
53 * Hudson (tjh@cryptsoft.com).
60 #include <openssl/ec.h>
63 /* Structure details are not part of the exported interface,
64 * so all this may change in future versions. */
67 /* used by EC_GROUP_new, EC_GROUP_set_curve_GFp, EC_GROUP_free, EC_GROUP_copy: */
68 int (*group_init)(EC_GROUP *);
69 /* int (*group_set)(EC_GROUP *, .....); */
70 int (*group_set_curve_GFp)(EC_GROUP *, const BIGNUM *p, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
71 void (*group_finish)(EC_GROUP *);
72 void (*group_clear_finish)(EC_GROUP *);
73 int (*group_copy)(EC_GROUP *, const EC_GROUP *);
75 /* used by EC_GROUP_set_generator: */
76 int (*group_set_generator)(EC_GROUP *, const EC_POINT *generator,
77 const BIGNUM *order, const BIGNUM *cofactor);
79 /* TODO: 'set' functions for EC_GROUPs */
82 /* used by EC_POINT_new, EC_POINT_free, EC_POINT_copy: */
83 int (*point_init)(EC_POINT *);
84 void (*point_finish)(EC_POINT *);
85 void (*point_clear_finish)(EC_POINT *);
86 int (*point_copy)(EC_POINT *, const EC_POINT *);
88 /* TODO: 'set' and 'get' functions for EC_POINTs */
90 /* used by EC_POINT_point2oct, EC_POINT_oct2point: */
91 size_t (*point2oct)(const EC_GROUP *, const EC_POINT *, point_conversion_form_t form,
92 unsigned char *buf, size_t len, BN_CTX *);
93 int (*oct2point)(const EC_GROUP *, EC_POINT *,
94 const unsigned char *buf, size_t len, BN_CTX *);
96 /* used by EC_POINT_add, EC_POINT_dbl: */
97 int (*add)(const EC_GROUP *, EC_POINT *r, const EC_POINT *a, const EC_POINT *b, BN_CTX *);
98 int (*dbl)(const EC_GROUP *, EC_POINT *r, const EC_POINT *a, BN_CTX *);
100 /* used by EC_POINT_is_at_infinity, EC_POINT_is_on_curve, EC_POINT_make_affine */
101 int (*is_at_infinity)(const EC_GROUP *, const EC_POINT *);
102 int (*is_on_curve)(const EC_GROUP *, const EC_POINT *, BN_CTX *);
103 int (*make_affine)(const EC_GROUP *, const EC_POINT *, BN_CTX *);
106 /* internal functions */
108 /* 'field_mult' and 'field_sqr' can be used by 'add' and 'dbl' so that
109 * the same implementations of point operations can be used with different
110 * optimized implementations of expensive field operations: */
111 int (*field_mult)(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *);
112 int (*field_sqr)(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *);
114 int (*field_encode)(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *); /* e.g. to Montgomery */
115 int (*field_decode)(const EC_GROUP *, BIGNUM *r, const BIGNUM *a, BN_CTX *); /* e.g. from Montgomery */
120 const EC_METHOD *meth;
123 void *(*extra_data_dup_func)(void *);
124 void (*extra_data_free_func)(void *);
125 void (*extra_data_clear_free_func)(void *);
127 /* All members except 'meth' and 'extra_data...' are handled by
128 * the method functions, even if they appear generic */
130 BIGNUM field; /* Field specification.
131 * For curves over GF(p), this is the modulus. */
132 void *field_data; /* method-specific (e.g., Montgomery structure) */
134 BIGNUM a, b; /* Curve coefficients.
135 * (Here the assumption is that BIGNUMs can be used
136 * or abused for all kinds of fields, not just GF(p).)
137 * For characteristic > 3, the curve is defined
138 * by a Weierstrass equation of the form
139 * Y^2 = X^3 + a*X + b.
141 int a_is_minus3; /* enable optimized point arithmetics for special case */
143 EC_POINT *generator; /* optional */
144 BIGNUM order, cofactor;
146 /* optional Lim/Lee precomputation table */
150 /* Basically a 'mixin' for extra data, but available for EC_GROUPs only
151 * (with visibility limited to 'package' level for now).
152 * We use the function pointers as index for retrieval; this obviates
153 * global ex_data-style index tables.
154 * (Currently, we have one slot only, but is is possible to extend this
157 int EC_GROUP_set_extra_data(EC_GROUP *, void *extra_data, void *(*extra_data_dup_func)(void *),
158 void (*extra_data_free_func)(void *), void (*extra_data_clear_free_func)(void *));
159 void *EC_GROUP_get_extra_data(EC_GROUP *, void *(*extra_data_dup_func)(void *),
160 void (*extra_data_free_func)(void *), void (*extra_data_clear_free_func)(void *));
161 void EC_GROUP_free_extra_data(EC_GROUP *);
162 void EC_GROUP_clear_free_extra_data(EC_GROUP *);
167 const EC_METHOD *meth;
169 /* All members except 'meth' are handled by the method functions,
170 * even if they appear generic */
174 BIGNUM Z; /* Jacobian projective coordinates:
175 * (X, Y, Z) represents (X/Z^2, Y/Z^3) if Z != 0 */
176 int Z_is_one; /* enable optimized point arithmetics for special case */