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Diffstat (limited to 'openssl/crypto/ec/ec2_smpl.c')
-rw-r--r--openssl/crypto/ec/ec2_smpl.c114
1 files changed, 91 insertions, 23 deletions
diff --git a/openssl/crypto/ec/ec2_smpl.c b/openssl/crypto/ec/ec2_smpl.c
index 5cd1eac41..cf357b462 100644
--- a/openssl/crypto/ec/ec2_smpl.c
+++ b/openssl/crypto/ec/ec2_smpl.c
@@ -14,7 +14,7 @@
*
*/
/* ====================================================================
- * Copyright (c) 1998-2003 The OpenSSL Project. All rights reserved.
+ * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -157,6 +157,7 @@ void ec_GF2m_simple_group_clear_finish(EC_GROUP *group)
group->poly[2] = 0;
group->poly[3] = 0;
group->poly[4] = 0;
+ group->poly[5] = -1;
}
@@ -174,8 +175,9 @@ int ec_GF2m_simple_group_copy(EC_GROUP *dest, const EC_GROUP *src)
dest->poly[2] = src->poly[2];
dest->poly[3] = src->poly[3];
dest->poly[4] = src->poly[4];
- bn_wexpand(&dest->a, (int)(dest->poly[0] + BN_BITS2 - 1) / BN_BITS2);
- bn_wexpand(&dest->b, (int)(dest->poly[0] + BN_BITS2 - 1) / BN_BITS2);
+ dest->poly[5] = src->poly[5];
+ if (bn_wexpand(&dest->a, (int)(dest->poly[0] + BN_BITS2 - 1) / BN_BITS2) == NULL) return 0;
+ if (bn_wexpand(&dest->b, (int)(dest->poly[0] + BN_BITS2 - 1) / BN_BITS2) == NULL) return 0;
for (i = dest->a.top; i < dest->a.dmax; i++) dest->a.d[i] = 0;
for (i = dest->b.top; i < dest->b.dmax; i++) dest->b.d[i] = 0;
return 1;
@@ -190,7 +192,7 @@ int ec_GF2m_simple_group_set_curve(EC_GROUP *group,
/* group->field */
if (!BN_copy(&group->field, p)) goto err;
- i = BN_GF2m_poly2arr(&group->field, group->poly, 5);
+ i = BN_GF2m_poly2arr(&group->field, group->poly, 6) - 1;
if ((i != 5) && (i != 3))
{
ECerr(EC_F_EC_GF2M_SIMPLE_GROUP_SET_CURVE, EC_R_UNSUPPORTED_FIELD);
@@ -199,12 +201,12 @@ int ec_GF2m_simple_group_set_curve(EC_GROUP *group,
/* group->a */
if (!BN_GF2m_mod_arr(&group->a, a, group->poly)) goto err;
- bn_wexpand(&group->a, (int)(group->poly[0] + BN_BITS2 - 1) / BN_BITS2);
+ if(bn_wexpand(&group->a, (int)(group->poly[0] + BN_BITS2 - 1) / BN_BITS2) == NULL) goto err;
for (i = group->a.top; i < group->a.dmax; i++) group->a.d[i] = 0;
/* group->b */
if (!BN_GF2m_mod_arr(&group->b, b, group->poly)) goto err;
- bn_wexpand(&group->b, (int)(group->poly[0] + BN_BITS2 - 1) / BN_BITS2);
+ if(bn_wexpand(&group->b, (int)(group->poly[0] + BN_BITS2 - 1) / BN_BITS2) == NULL) goto err;
for (i = group->b.top; i < group->b.dmax; i++) group->b.d[i] = 0;
ret = 1;
@@ -404,18 +406,94 @@ int ec_GF2m_simple_point_get_affine_coordinates(const EC_GROUP *group, const EC_
}
-/* Include patented algorithms. */
-#include "ec2_smpt.c"
+/* Calculates and sets the affine coordinates of an EC_POINT from the given
+ * compressed coordinates. Uses algorithm 2.3.4 of SEC 1.
+ * Note that the simple implementation only uses affine coordinates.
+ *
+ * The method is from the following publication:
+ *
+ * Harper, Menezes, Vanstone:
+ * "Public-Key Cryptosystems with Very Small Key Lengths",
+ * EUROCRYPT '92, Springer-Verlag LNCS 658,
+ * published February 1993
+ *
+ * US Patents 6,141,420 and 6,618,483 (Vanstone, Mullin, Agnew) describe
+ * the same method, but claim no priority date earlier than July 29, 1994
+ * (and additionally fail to cite the EUROCRYPT '92 publication as prior art).
+ */
+int ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *group, EC_POINT *point,
+ const BIGNUM *x_, int y_bit, BN_CTX *ctx)
+ {
+ BN_CTX *new_ctx = NULL;
+ BIGNUM *tmp, *x, *y, *z;
+ int ret = 0, z0;
+
+ /* clear error queue */
+ ERR_clear_error();
+
+ if (ctx == NULL)
+ {
+ ctx = new_ctx = BN_CTX_new();
+ if (ctx == NULL)
+ return 0;
+ }
+
+ y_bit = (y_bit != 0) ? 1 : 0;
+
+ BN_CTX_start(ctx);
+ tmp = BN_CTX_get(ctx);
+ x = BN_CTX_get(ctx);
+ y = BN_CTX_get(ctx);
+ z = BN_CTX_get(ctx);
+ if (z == NULL) goto err;
+
+ if (!BN_GF2m_mod_arr(x, x_, group->poly)) goto err;
+ if (BN_is_zero(x))
+ {
+ if (!BN_GF2m_mod_sqrt_arr(y, &group->b, group->poly, ctx)) goto err;
+ }
+ else
+ {
+ if (!group->meth->field_sqr(group, tmp, x, ctx)) goto err;
+ if (!group->meth->field_div(group, tmp, &group->b, tmp, ctx)) goto err;
+ if (!BN_GF2m_add(tmp, &group->a, tmp)) goto err;
+ if (!BN_GF2m_add(tmp, x, tmp)) goto err;
+ if (!BN_GF2m_mod_solve_quad_arr(z, tmp, group->poly, ctx))
+ {
+ unsigned long err = ERR_peek_last_error();
+
+ if (ERR_GET_LIB(err) == ERR_LIB_BN && ERR_GET_REASON(err) == BN_R_NO_SOLUTION)
+ {
+ ERR_clear_error();
+ ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES, EC_R_INVALID_COMPRESSED_POINT);
+ }
+ else
+ ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES, ERR_R_BN_LIB);
+ goto err;
+ }
+ z0 = (BN_is_odd(z)) ? 1 : 0;
+ if (!group->meth->field_mul(group, y, x, z, ctx)) goto err;
+ if (z0 != y_bit)
+ {
+ if (!BN_GF2m_add(y, y, x)) goto err;
+ }
+ }
+
+ if (!EC_POINT_set_affine_coordinates_GF2m(group, point, x, y, ctx)) goto err;
+
+ ret = 1;
+
+ err:
+ BN_CTX_end(ctx);
+ if (new_ctx != NULL)
+ BN_CTX_free(new_ctx);
+ return ret;
+ }
/* Converts an EC_POINT to an octet string.
* If buf is NULL, the encoded length will be returned.
* If the length len of buf is smaller than required an error will be returned.
- *
- * The point compression section of this function is patented by Certicom Corp.
- * under US Patent 6,141,420. Point compression is disabled by default and can
- * be enabled by defining the preprocessor macro OPENSSL_EC_BIN_PT_COMP at
- * Configure-time.
*/
size_t ec_GF2m_simple_point2oct(const EC_GROUP *group, const EC_POINT *point, point_conversion_form_t form,
unsigned char *buf, size_t len, BN_CTX *ctx)
@@ -426,14 +504,6 @@ size_t ec_GF2m_simple_point2oct(const EC_GROUP *group, const EC_POINT *point, po
BIGNUM *x, *y, *yxi;
size_t field_len, i, skip;
-#ifndef OPENSSL_EC_BIN_PT_COMP
- if ((form == POINT_CONVERSION_COMPRESSED) || (form == POINT_CONVERSION_HYBRID))
- {
- ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_DISABLED);
- goto err;
- }
-#endif
-
if ((form != POINT_CONVERSION_COMPRESSED)
&& (form != POINT_CONVERSION_UNCOMPRESSED)
&& (form != POINT_CONVERSION_HYBRID))
@@ -488,13 +558,11 @@ size_t ec_GF2m_simple_point2oct(const EC_GROUP *group, const EC_POINT *point, po
if (!EC_POINT_get_affine_coordinates_GF2m(group, point, x, y, ctx)) goto err;
buf[0] = form;
-#ifdef OPENSSL_EC_BIN_PT_COMP
if ((form != POINT_CONVERSION_UNCOMPRESSED) && !BN_is_zero(x))
{
if (!group->meth->field_div(group, yxi, y, x, ctx)) goto err;
if (BN_is_odd(yxi)) buf[0]++;
}
-#endif
i = 1;
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-08 22:06:40 +0000