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-rw-r--r--openssl/crypto/ec/ec2_smpt.c141
1 files changed, 141 insertions, 0 deletions
diff --git a/openssl/crypto/ec/ec2_smpt.c b/openssl/crypto/ec/ec2_smpt.c
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+/* crypto/ec/ec2_smpt.c */
+/* This code was originally written by Douglas Stebila
+ * <dstebila@student.math.uwaterloo.ca> for the OpenSSL project.
+ */
+/* ====================================================================
+ * Copyright (c) 1998-2002 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
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ * software must display the following acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ * endorse or promote products derived from this software without
+ * prior written permission. For written permission, please contact
+ * openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ * nor may "OpenSSL" appear in their names without prior written
+ * permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ * acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com). This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+
+
+/* Calaculates 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.
+ *
+ * This algorithm is patented by Certicom Corp. under US Patent 6,141,420
+ * (for licensing information, contact licensing@certicom.com).
+ * This function is disabled by default and can be enabled by defining the
+ * preprocessor macro OPENSSL_EC_BIN_PT_COMP at Configure-time.
+ */
+int ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *group, EC_POINT *point,
+ const BIGNUM *x_, int y_bit, BN_CTX *ctx)
+ {
+#ifndef OPENSSL_EC_BIN_PT_COMP
+ ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES, ERR_R_DISABLED);
+ return 0;
+#else
+ 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;
+#endif
+ }