ECDSA support

Submitted by: Nils Larsch <nla@trustcenter.de>

1 files changed, 381 insertions, 0 deletions

diff --git a/crypto/ecdsa/ecs_ossl.c b/crypto/ecdsa/ecs_ossl.c
new file mode 100644
index 0000000000..5a36707cfb
--- /dev/null
+++ b/crypto/ecdsa/ecs_ossl.c
@@ -0,0 +1,381 @@
+/* crypto/ecdsa/ecs_ossl.c */
+/* ====================================================================
+ * 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).
+ *
+ */
+/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
+ * All rights reserved.
+ *
+ * This package is an SSL implementation written
+ * by Eric Young (eay@cryptsoft.com).
+ * The implementation was written so as to conform with Netscapes SSL.
+ * 
+ * This library is free for commercial and non-commercial use as long as
+ * the following conditions are aheared to.  The following conditions
+ * apply to all code found in this distribution, be it the RC4, RSA,
+ * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
+ * included with this distribution is covered by the same copyright terms
+ * except that the holder is Tim Hudson (tjh@cryptsoft.com).
+ * 
+ * Copyright remains Eric Young's, and as such any Copyright notices in
+ * the code are not to be removed.
+ * If this package is used in a product, Eric Young should be given attribution
+ * as the author of the parts of the library used.
+ * This can be in the form of a textual message at program startup or
+ * in documentation (online or textual) provided with the package.
+ * 
+ * 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 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 acknowledgement:
+ *    "This product includes cryptographic software written by
+ *     Eric Young (eay@cryptsoft.com)"
+ *    The word 'cryptographic' can be left out if the rouines from the library
+ *    being used are not cryptographic related :-).
+ * 4. If you include any Windows specific code (or a derivative thereof) from 
+ *    the apps directory (application code) you must include an acknowledgement:
+ *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
+ * 
+ * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
+ * ANY EXPRESS 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 AUTHOR OR 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.
+ * 
+ * The licence and distribution terms for any publically available version or
+ * derivative of this code cannot be changed.  i.e. this code cannot simply be
+ * copied and put under another distribution licence
+ * [including the GNU Public Licence.]
+ */
+#include "cryptlib.h"
+#include <openssl/ecdsa.h>
+
+/* TODO : general case */
+#define	EC_POINT_get_affine_coordinates EC_POINT_get_affine_coordinates_GFp
+
+static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dlen, ECDSA *ecdsa);
+static int ecdsa_sign_setup(ECDSA *ecdsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp);
+static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, ECDSA_SIG *sig,
+		           ECDSA *ecdsa);
+
+static ECDSA_METHOD openssl_ecdsa_meth = {
+"OpenSSL ECDSA method",
+ecdsa_do_sign,
+ecdsa_sign_setup,
+ecdsa_do_verify,
+0,
+NULL
+};
+
+const ECDSA_METHOD *ECDSA_OpenSSL(void)
+{
+	return &openssl_ecdsa_meth;
+}
+
+static int ecdsa_sign_setup(ECDSA *ecdsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp)
+{
+	BN_CTX   *ctx = NULL;
+	BIGNUM	 k,*kinv=NULL,*r=NULL,*order=NULL,*X=NULL;
+	EC_POINT *tmp_point=NULL;
+	int 	 ret = 0,reason = ERR_R_BN_LIB;
+	if (!ecdsa  || !ecdsa->group || !ecdsa->pub_key || !ecdsa->priv_key)
+	{
+		reason = ECDSA_R_MISSING_PARAMETERS;
+		return 0;
+	}
+	if (ctx_in == NULL) 
+	{
+		if ((ctx=BN_CTX_new()) == NULL) goto err;
+	}
+	else
+		ctx=ctx_in;
+
+	if ((r = BN_new()) == NULL) goto err;
+	if ((order = BN_new()) == NULL) goto err;
+	if ((X = BN_new()) == NULL) goto err;
+	if ((tmp_point = EC_POINT_new(ecdsa->group)) == NULL)
+	{
+		reason = ERR_R_EC_LIB;
+		goto err;
+	}
+	if (!EC_POINT_copy(tmp_point,EC_GROUP_get0_generator(ecdsa->group)))
+	{
+		reason = ERR_R_EC_LIB;
+		goto err;
+	}
+	if (!EC_GROUP_get_order(ecdsa->group,order,ctx))
+	{
+		reason = ERR_R_EC_LIB;
+		goto err;
+	}
+	
+	do
+	{
+		/* get random k */	
+		BN_init(&k);
+		do
+			if (!BN_rand_range(&k,order))
+			{
+				reason = ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED;
+				goto err;
+			}
+		while (BN_is_zero(&k));
+
+		/* compute r the x-coordinate of generator * k */
+		if (!EC_POINT_mul(ecdsa->group,tmp_point,&k,NULL,NULL,ctx) 
+		    || !EC_POINT_get_affine_coordinates(ecdsa->group,tmp_point,X,NULL,ctx))
+		{
+			reason = ERR_R_EC_LIB;
+			goto err;
+		}
+		if (!BN_nnmod(r,X,order,ctx)) goto err;
+	}
+	while (BN_is_zero(r));
+
+	/* compute the inverse of k */
+	if ((kinv = BN_mod_inverse(NULL,&k,order,ctx)) == NULL) goto err;
+
+	if (*rp == NULL)
+		BN_clear_free(*rp);
+	*rp = r;
+	if (*kinvp == NULL) 
+		BN_clear_free(*kinvp);
+	*kinvp = kinv;
+	kinv = NULL;
+	ret = 1;
+err:
+	if (!ret)
+	{
+		ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,reason);
+		if (kinv != NULL) BN_clear_free(kinv);
+		if (r != NULL) BN_clear_free(r);
+	}
+	if (ctx_in == NULL) 
+		BN_CTX_free(ctx);
+	if (kinv != NULL)
+		BN_clear_free(kinv);
+	if (order != NULL)
+		BN_clear_free(order);
+	if (tmp_point != NULL) 
+		EC_POINT_free(tmp_point);
+	if (X)	BN_clear_free(X);
+	BN_clear_free(&k);
+	return(ret);
+}
+
+
+static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dgst_len, ECDSA *ecdsa)
+{
+	BIGNUM *kinv=NULL,*r=NULL,*s=NULL,*m=NULL,*tmp=NULL,*order=NULL;
+	BIGNUM xr;
+	BN_CTX *ctx=NULL;
+	int reason=ERR_R_BN_LIB;
+	ECDSA_SIG *ret=NULL;
+
+	if (!ecdsa || !ecdsa->group || !ecdsa->pub_key || !ecdsa->priv_key)
+	{
+		reason = ECDSA_R_MISSING_PARAMETERS;
+		goto err;
+	}
+	BN_init(&xr);
+
+	if ((ctx = BN_CTX_new()) == NULL) goto err;
+	if ((order = BN_new()) == NULL) goto err;
+	if ((tmp = BN_new()) == NULL) goto err;
+	if ((m = BN_new()) == NULL) goto err;
+	if ((s = BN_new()) == NULL) goto err;
+
+	if (!EC_GROUP_get_order(ecdsa->group,order,ctx))
+	{
+		reason = ECDSA_R_ERR_EC_LIB;
+		goto err;
+	}
+	if (dgst_len > BN_num_bytes(order))
+	{
+		reason = ECDSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE;
+		goto err;
+	}
+
+	if (BN_bin2bn(dgst,dgst_len,m) == NULL) goto err;
+	do
+	{
+		if ((ecdsa->kinv == NULL) || (ecdsa->r == NULL))
+		{
+			if (!ECDSA_sign_setup(ecdsa,ctx,&kinv,&r)) goto err;
+		}
+		else
+		{
+			kinv = ecdsa->kinv;
+			ecdsa->kinv = NULL;
+			r = ecdsa->r;
+			ecdsa->r = NULL;
+		}
+
+		if (!BN_mod_mul(tmp,ecdsa->priv_key,r,order,ctx)) goto err;
+		if (!BN_add(s,tmp,m)) goto err;
+		if (BN_cmp(s,order) > 0)
+			BN_sub(s,s,order);
+		if (!BN_mod_mul(s,s,kinv,order,ctx)) goto err;
+	}
+	while (BN_is_zero(s));
+
+	if ((ret = ECDSA_SIG_new()) == NULL)
+	{
+		reason = ECDSA_R_SIGNATURE_MALLOC_FAILED;
+		goto err;
+	}
+	ret->r = r;
+	ret->s = s;
+	
+err:
+	if (!ret)
+		{
+		ECDSAerr(ECDSA_F_ECDSA_DO_SIGN,reason);
+		BN_free(r);
+		BN_free(s);
+		}
+	if (ctx   != NULL) BN_CTX_free(ctx);
+	if (m     != NULL) BN_clear_free(m);
+	if (tmp   != NULL) BN_clear_free(tmp);
+	if (order != NULL) BN_clear_free(order);
+	if (kinv  != NULL) BN_clear_free(kinv);
+	return(ret);
+}
+
+static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, ECDSA_SIG *sig,
+		  	   ECDSA *ecdsa)
+{
+	BN_CTX *ctx;
+	BIGNUM *order=NULL,*u1=NULL,*u2=NULL,*m=NULL,*X=NULL;
+	EC_POINT *point=NULL;
+	int ret = -1,reason = ERR_R_BN_LIB;
+	if (!ecdsa || !ecdsa->group || !ecdsa->pub_key || !sig)
+	{
+		reason = ECDSA_R_MISSING_PARAMETERS;
+		return -1;
+	}
+
+	if ((ctx = BN_CTX_new()) == NULL) goto err;
+	if ((order = BN_new()) == NULL) goto err;
+	if ((u1 = BN_new()) == NULL) goto err;
+	if ((u2 = BN_new()) == NULL) goto err;
+	if ((m  = BN_new()) == NULL) goto err;
+	if ((X  = BN_new()) == NULL) goto err;
+	if (!EC_GROUP_get_order(ecdsa->group,order,ctx)) goto err;
+
+	if (BN_is_zero(sig->r) || sig->r->neg || BN_ucmp(sig->r, order) >= 0)
+	{
+		reason = ECDSA_R_BAD_SIGNATURE;
+		ret = 0;
+		goto err;
+	}
+	if (BN_is_zero(sig->s) || sig->s->neg || BN_ucmp(sig->s, order) >= 0)
+	{
+		reason = ECDSA_R_BAD_SIGNATURE;
+		ret = 0;
+		goto err;
+	}
+
+	/* calculate tmp1 = inv(S) mod order */
+	if ((BN_mod_inverse(u2,sig->s,order,ctx)) == NULL) goto err;
+	/* digest -> m */
+	if (BN_bin2bn(dgst,dgst_len,m) == NULL) goto err;
+	/* u1 = m * tmp mod order */
+	if (!BN_mod_mul(u1,m,u2,order,ctx)) goto err;
+	/* u2 = r * w mod q */
+	if (!BN_mod_mul(u2,sig->r,u2,order,ctx)) goto err;
+
+	if ((point = EC_POINT_new(ecdsa->group)) == NULL)
+	{
+		reason = ERR_R_EC_LIB;
+		goto err;
+	}
+	if (!EC_POINT_copy(point,EC_GROUP_get0_generator(ecdsa->group)))
+	{
+		reason = ERR_R_EC_LIB;
+		goto err;
+	}
+	if (!EC_POINT_mul(ecdsa->group,point,u1,ecdsa->pub_key,u2,ctx)
+	    || !EC_POINT_get_affine_coordinates(ecdsa->group,point,X,NULL,ctx))
+	{
+		reason = ERR_R_EC_LIB;
+		goto err;
+	}
+	if (!BN_nnmod(u1,X,order,ctx)) goto err;
+
+	/*  is now in u1.  If the signature is correct, it will be
+	 * equal to R. */
+	ret = (BN_ucmp(u1,sig->r) == 0);
+
+	err:
+	if (ret != 1) ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY,reason);
+	if (ctx != NULL) BN_CTX_free(ctx);
+	if (u1  != NULL) BN_clear_free(u1);
+	if (u2  != NULL) BN_clear_free(u2);
+	if (m   != NULL) BN_clear_free(m);
+	if (X   != NULL) BN_clear_free(X);
+	if (order != NULL) BN_clear_free(order);
+	if (point != NULL) EC_POINT_free(point);
+	return(ret);
+}