text: /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
   * project 2006.
   */
  /* ====================================================================
   * Copyright (c) 2006 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
   *    licensing@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).
   *
   */
  
  #include <stdio.h>
  #include "cryptlib.h"
  #include <openssl/x509.h>
  #include <openssl/ec.h>
  #include <openssl/bn.h>
  #ifndef OPENSSL_NO_CMS
  #include <openssl/cms.h>
  #endif
  #include "asn1_locl.h"
  
  static int eckey_param2type(int *pptype, void **ppval, EC_KEY *ec_key)
  	{
  	const EC_GROUP  *group;
  	int nid;
  	if (ec_key == NULL || (group = EC_KEY_get0_group(ec_key)) == NULL) 
  	{
  		ECerr(EC_F_ECKEY_PARAM2TYPE, EC_R_MISSING_PARAMETERS);
  		return 0;
  	}
  	if (EC_GROUP_get_asn1_flag(group)
                       && (nid = EC_GROUP_get_curve_name(group)))
  		/* we have a 'named curve' => just set the OID */
  		{
  		*ppval = OBJ_nid2obj(nid);
  		*pptype = V_ASN1_OBJECT;
  		}
  	else	/* explicit parameters */
  		{
  		ASN1_STRING *pstr = NULL;
  		pstr = ASN1_STRING_new();
  		if (!pstr)
  			return 0;
  		pstr->length = i2d_ECParameters(ec_key, &pstr->data);
  		if (pstr->length < 0)
  			{
  			ASN1_STRING_free(pstr);
  			ECerr(EC_F_ECKEY_PARAM2TYPE, ERR_R_EC_LIB);
  			return 0;
  			}
  		*ppval = pstr;
  		*pptype = V_ASN1_SEQUENCE;
  		}
  	return 1;
  	}
  
  static int eckey_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
  	{
  	EC_KEY *ec_key = pkey->pkey.ec;
  	void *pval = NULL;
  	int ptype;
  	unsigned char *penc = NULL, *p;
  	int penclen;
  
  	if (!eckey_param2type(&ptype, &pval, ec_key))
  		{
  		ECerr(EC_F_ECKEY_PUB_ENCODE, ERR_R_EC_LIB);
  		return 0;
  		}
  	penclen = i2o_ECPublicKey(ec_key, NULL);
  	if (penclen <= 0)
  		goto err;
  	penc = OPENSSL_malloc(penclen);
  	if (!penc)
  		goto err;
  	p = penc;
  	penclen = i2o_ECPublicKey(ec_key, &p);
  	if (penclen <= 0)
  		goto err;
  	if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_EC),
  				ptype, pval, penc, penclen))
  		return 1;
  	err:
  	if (ptype == V_ASN1_OBJECT)
  		ASN1_OBJECT_free(pval);
  	else
  		ASN1_STRING_free(pval);
  	if (penc)
  		OPENSSL_free(penc);
  	return 0;
  	}
  
  static EC_KEY *eckey_type2param(int ptype, void *pval)
  	{
  	EC_KEY *eckey = NULL;
  	if (ptype == V_ASN1_SEQUENCE)
  		{
  		ASN1_STRING *pstr = pval;
  		const unsigned char *pm = NULL;
  		int pmlen;
  		pm = pstr->data;
  		pmlen = pstr->length;
  		if (!(eckey = d2i_ECParameters(NULL, &pm, pmlen)))
  			{
  			ECerr(EC_F_ECKEY_TYPE2PARAM, EC_R_DECODE_ERROR);
  			goto ecerr;
  			}
  		}
  	else if (ptype == V_ASN1_OBJECT)
  		{
  		ASN1_OBJECT *poid = pval;
  		EC_GROUP *group;
  
  		/* type == V_ASN1_OBJECT => the parameters are given
  		 * by an asn1 OID
  		 */
  		if ((eckey = EC_KEY_new()) == NULL)
  			{
  			ECerr(EC_F_ECKEY_TYPE2PARAM, ERR_R_MALLOC_FAILURE);
  			goto ecerr;
  			}
  		group = EC_GROUP_new_by_curve_name(OBJ_obj2nid(poid));
  		if (group == NULL)
  			goto ecerr;
  		EC_GROUP_set_asn1_flag(group, OPENSSL_EC_NAMED_CURVE);
  		if (EC_KEY_set_group(eckey, group) == 0)
  			goto ecerr;
  		EC_GROUP_free(group);
  		}
  	else
  		{
  		ECerr(EC_F_ECKEY_TYPE2PARAM, EC_R_DECODE_ERROR);
  		goto ecerr;
  		}
  
  	return eckey;
  
  	ecerr:
  	if (eckey)
  		EC_KEY_free(eckey);
  	return NULL;
  	}
  
  static int eckey_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
  	{
  	const unsigned char *p = NULL;
  	void *pval;
  	int ptype, pklen;
  	EC_KEY *eckey = NULL;
  	X509_ALGOR *palg;
  
  	if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey))
  		return 0;
  	X509_ALGOR_get0(NULL, &ptype, &pval, palg);
  
  	eckey = eckey_type2param(ptype, pval);
  
  	if (!eckey)
  		{
  		ECerr(EC_F_ECKEY_PUB_DECODE, ERR_R_EC_LIB);
  		return 0;
  		}
  
  	/* We have parameters now set public key */
  	if (!o2i_ECPublicKey(&eckey, &p, pklen))
  		{
  		ECerr(EC_F_ECKEY_PUB_DECODE, EC_R_DECODE_ERROR);
  		goto ecerr;
  		}
  
  	EVP_PKEY_assign_EC_KEY(pkey, eckey);
  	return 1;
  
  	ecerr:
  	if (eckey)
  		EC_KEY_free(eckey);
  	return 0;
  	}
  
  static int eckey_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
  	{
  	int  r;
  	const EC_GROUP *group = EC_KEY_get0_group(b->pkey.ec);
  	const EC_POINT *pa = EC_KEY_get0_public_key(a->pkey.ec),
  	               *pb = EC_KEY_get0_public_key(b->pkey.ec);
  	r = EC_POINT_cmp(group, pa, pb, NULL);
  	if (r == 0)
  		return 1;
  	if (r == 1)
  		return 0;
  	return -2;
  	}
  
  static int eckey_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8)
  	{
  	const unsigned char *p = NULL;
  	void *pval;
  	int ptype, pklen;
  	EC_KEY *eckey = NULL;
  	X509_ALGOR *palg;
  
  	if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8))
  		return 0;
  	X509_ALGOR_get0(NULL, &ptype, &pval, palg);
  
  	eckey = eckey_type2param(ptype, pval);
  
  	if (!eckey)
  		goto ecliberr;
  
  	/* We have parameters now set private key */
  	if (!d2i_ECPrivateKey(&eckey, &p, pklen))
  		{
  		ECerr(EC_F_ECKEY_PRIV_DECODE, EC_R_DECODE_ERROR);
  		goto ecerr;
  		}
  
  	/* calculate public key (if necessary) */
  	if (EC_KEY_get0_public_key(eckey) == NULL)
  		{
  		const BIGNUM *priv_key;
  		const EC_GROUP *group;
  		EC_POINT *pub_key;
  		/* the public key was not included in the SEC1 private
  		 * key => calculate the public key */
  		group   = EC_KEY_get0_group(eckey);
  		pub_key = EC_POINT_new(group);
  		if (pub_key == NULL)
  			{
  			ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
  			goto ecliberr;
  			}
  		if (!EC_POINT_copy(pub_key, EC_GROUP_get0_generator(group)))
  			{
  			EC_POINT_free(pub_key);
  			ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
  			goto ecliberr;
  			}
  		priv_key = EC_KEY_get0_private_key(eckey);
  		if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, NULL))
  			{
  			EC_POINT_free(pub_key);
  			ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
  			goto ecliberr;
  			}
  		if (EC_KEY_set_public_key(eckey, pub_key) == 0)
  			{
  			EC_POINT_free(pub_key);
  			ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
  			goto ecliberr;
  			}
  		EC_POINT_free(pub_key);
  		}
  
  	EVP_PKEY_assign_EC_KEY(pkey, eckey);
  	return 1;
  
  	ecliberr:
  	ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
  	ecerr:
  	if (eckey)
  		EC_KEY_free(eckey);
  	return 0;
  	}
  
  static int eckey_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
  {
  	EC_KEY		*ec_key;
  	unsigned char	*ep, *p;
  	int 		eplen, ptype;
  	void		*pval;
  	unsigned int    tmp_flags, old_flags;
  
  	ec_key = pkey->pkey.ec;
  
  	if (!eckey_param2type(&ptype, &pval, ec_key))
  		{
  		ECerr(EC_F_ECKEY_PRIV_ENCODE, EC_R_DECODE_ERROR);
  		return 0;
  		}
  
  	/* set the private key */
  
  	/* do not include the parameters in the SEC1 private key
  	 * see PKCS#11 12.11 */
  	old_flags = EC_KEY_get_enc_flags(ec_key);
  	tmp_flags = old_flags | EC_PKEY_NO_PARAMETERS;
  	EC_KEY_set_enc_flags(ec_key, tmp_flags);
  	eplen = i2d_ECPrivateKey(ec_key, NULL);
  	if (!eplen)
  	{
  		EC_KEY_set_enc_flags(ec_key, old_flags);
  		ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_EC_LIB);
  		return 0;
  	}
  	ep = (unsigned char *) OPENSSL_malloc(eplen);
  	if (!ep)
  	{
  		EC_KEY_set_enc_flags(ec_key, old_flags);
  		ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
  		return 0;
  	}
  	p = ep;
  	if (!i2d_ECPrivateKey(ec_key, &p))
  	{
  		EC_KEY_set_enc_flags(ec_key, old_flags);
  		OPENSSL_free(ep);
  		ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_EC_LIB);
  		return 0;
  	}
  	/* restore old encoding flags */
  	EC_KEY_set_enc_flags(ec_key, old_flags);
  
  	if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_X9_62_id_ecPublicKey), 0,
  				ptype, pval, ep, eplen))
  		return 0;
  
  	return 1;
  }
  
  static int int_ec_size(const EVP_PKEY *pkey)
  	{
  	return ECDSA_size(pkey->pkey.ec);
  	}
  
  static int ec_bits(const EVP_PKEY *pkey)
  	{
  	BIGNUM *order = BN_new();
  	const EC_GROUP *group;
  	int ret;
  
  	if (!order)
  		{
  		ERR_clear_error();
  		return 0;
  		}
  	group = EC_KEY_get0_group(pkey->pkey.ec);
  	if (!EC_GROUP_get_order(group, order, NULL))
  		{
  		ERR_clear_error();
  		return 0;
  		}
  
  	ret = BN_num_bits(order);
  	BN_free(order);
  	return ret;
  	}
  
  static int ec_missing_parameters(const EVP_PKEY *pkey)
  	{
  	if (EC_KEY_get0_group(pkey->pkey.ec) == NULL)
  		return 1;
  	return 0;
  	}
  
  static int ec_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from)
  	{
  	EC_GROUP *group = EC_GROUP_dup(EC_KEY_get0_group(from->pkey.ec));
  	if (group == NULL)
  		return 0;
  	if (EC_KEY_set_group(to->pkey.ec, group) == 0)
  		return 0;
  	EC_GROUP_free(group);
  	return 1;
  	}
  
  static int ec_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b)
  	{
  	const EC_GROUP *group_a = EC_KEY_get0_group(a->pkey.ec),
  	               *group_b = EC_KEY_get0_group(b->pkey.ec);
  	if (EC_GROUP_cmp(group_a, group_b, NULL))
  		return 0;
  	else
  		return 1;
  	}
  
  static void int_ec_free(EVP_PKEY *pkey)
  	{
  	EC_KEY_free(pkey->pkey.ec);
  	}
  
  static int do_EC_KEY_print(BIO *bp, const EC_KEY *x, int off, int ktype)
  	{
  	unsigned char *buffer=NULL;
  	const char *ecstr;
  	size_t	buf_len=0, i;
  	int     ret=0, reason=ERR_R_BIO_LIB;
  	BIGNUM  *pub_key=NULL, *order=NULL;
  	BN_CTX  *ctx=NULL;
  	const EC_GROUP *group;
  	const EC_POINT *public_key;
  	const BIGNUM *priv_key;
   
  	if (x == NULL || (group = EC_KEY_get0_group(x)) == NULL)
  		{
  		reason = ERR_R_PASSED_NULL_PARAMETER;
  		goto err;
  		}
  
  	ctx = BN_CTX_new();
  	if (ctx == NULL)
  		{
  		reason = ERR_R_MALLOC_FAILURE;
  		goto err;
  		}
  
  	if (ktype > 0)
  		{
  		public_key = EC_KEY_get0_public_key(x);
  		if ((pub_key = EC_POINT_point2bn(group, public_key,
  			EC_KEY_get_conv_form(x), NULL, ctx)) == NULL)
  			{
  			reason = ERR_R_EC_LIB;
  			goto err;
  			}
  		if (pub_key)
  			buf_len = (size_t)BN_num_bytes(pub_key);
  		}
  
  	if (ktype == 2)
  		{
  		priv_key = EC_KEY_get0_private_key(x);
  		if (priv_key && (i = (size_t)BN_num_bytes(priv_key)) > buf_len)
  			buf_len = i;
  		}
  	else
  		priv_key = NULL;
  
  	if (ktype > 0)
  		{
  		buf_len += 10;
  		if ((buffer = OPENSSL_malloc(buf_len)) == NULL)
  			{
  			reason = ERR_R_MALLOC_FAILURE;
  			goto err;
  			}
  		}
  	if (ktype == 2)
  		ecstr = "Private-Key";
  	else if (ktype == 1)
  		ecstr = "Public-Key";
  	else
  		ecstr = "ECDSA-Parameters";
  
  	if (!BIO_indent(bp, off, 128))
  		goto err;
  	if ((order = BN_new()) == NULL)
  		goto err;
  	if (!EC_GROUP_get_order(group, order, NULL))
  		goto err;
  	if (BIO_printf(bp, "%s: (%d bit)\n", ecstr,
  		BN_num_bits(order)) <= 0) goto err;
    
  	if ((priv_key != NULL) && !ASN1_bn_print(bp, "priv:", priv_key, 
  		buffer, off))
  		goto err;
  	if ((pub_key != NULL) && !ASN1_bn_print(bp, "pub: ", pub_key,
  		buffer, off))
  		goto err;
  	if (!ECPKParameters_print(bp, group, off))
  		goto err;
  	ret=1;
  err:
  	if (!ret)
   		ECerr(EC_F_DO_EC_KEY_PRINT, reason);
  	if (pub_key) 
  		BN_free(pub_key);
  	if (order)
  		BN_free(order);
  	if (ctx)
  		BN_CTX_free(ctx);
  	if (buffer != NULL)
  		OPENSSL_free(buffer);
  	return(ret);
  	}
  
  static int eckey_param_decode(EVP_PKEY *pkey,
  					const unsigned char **pder, int derlen)
  	{
  	EC_KEY *eckey;
  	if (!(eckey = d2i_ECParameters(NULL, pder, derlen)))
  		{
  		ECerr(EC_F_ECKEY_PARAM_DECODE, ERR_R_EC_LIB);
  		return 0;
  		}
  	EVP_PKEY_assign_EC_KEY(pkey, eckey);
  	return 1;
  	}
  
  static int eckey_param_encode(const EVP_PKEY *pkey, unsigned char **pder)
  	{
  	return i2d_ECParameters(pkey->pkey.ec, pder);
  	}
  
  static int eckey_param_print(BIO *bp, const EVP_PKEY *pkey, int indent,
  							ASN1_PCTX *ctx)
  	{
  	return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 0);
  	}
  
  static int eckey_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent,
  							ASN1_PCTX *ctx)
  	{
  	return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 1);
  	}
  
  
  static int eckey_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent,
  							ASN1_PCTX *ctx)
  	{
  	return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 2);
  	}
  
  static int old_ec_priv_decode(EVP_PKEY *pkey,
  					const unsigned char **pder, int derlen)
  	{
  	EC_KEY *ec;
  	if (!(ec = d2i_ECPrivateKey (NULL, pder, derlen)))
  		{
  		ECerr(EC_F_OLD_EC_PRIV_DECODE, EC_R_DECODE_ERROR);
  		return 0;
  		}
  	EVP_PKEY_assign_EC_KEY(pkey, ec);
  	return 1;
  	}
  
  static int old_ec_priv_encode(const EVP_PKEY *pkey, unsigned char **pder)
  	{
  	return i2d_ECPrivateKey(pkey->pkey.ec, pder);
  	}
  
  static int ec_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
  	{
  	switch (op)
  		{
  		case ASN1_PKEY_CTRL_PKCS7_SIGN:
  		if (arg1 == 0)
  			{
  			int snid, hnid;
  			X509_ALGOR *alg1, *alg2;
  			PKCS7_SIGNER_INFO_get0_algs(arg2, NULL, &alg1, &alg2);
  			if (alg1 == NULL || alg1->algorithm == NULL)
  				return -1;
  			hnid = OBJ_obj2nid(alg1->algorithm);
  			if (hnid == NID_undef)
  				return -1;
  			if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey)))
  				return -1; 
  			X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
  			}
  		return 1;
  #ifndef OPENSSL_NO_CMS
  		case ASN1_PKEY_CTRL_CMS_SIGN:
  		if (arg1 == 0)
  			{
  			int snid, hnid;
  			X509_ALGOR *alg1, *alg2;
  			CMS_SignerInfo_get0_algs(arg2, NULL, NULL,
  								&alg1, &alg2);
  			if (alg1 == NULL || alg1->algorithm == NULL)
  				return -1;
  			hnid = OBJ_obj2nid(alg1->algorithm);
  			if (hnid == NID_undef)
  				return -1;
  			if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey)))
  				return -1; 
  			X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
  			}
  		return 1;
  #endif
  
  		case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
  		*(int *)arg2 = NID_sha1;
  		return 2;
  
  		default:
  		return -2;
  
  		}
  
  	}
  
  const EVP_PKEY_ASN1_METHOD eckey_asn1_meth = 
  	{
  	EVP_PKEY_EC,
  	EVP_PKEY_EC,
  	0,
  	"EC",
  	"OpenSSL EC algorithm",
  
  	eckey_pub_decode,
  	eckey_pub_encode,
  	eckey_pub_cmp,
  	eckey_pub_print,
  
  	eckey_priv_decode,
  	eckey_priv_encode,
  	eckey_priv_print,
  
  	int_ec_size,
  	ec_bits,
  
  	eckey_param_decode,
  	eckey_param_encode,
  	ec_missing_parameters,
  	ec_copy_parameters,
  	ec_cmp_parameters,
  	eckey_param_print,
  
  	int_ec_free,
  	ec_pkey_ctrl,
  	old_ec_priv_decode,
  	old_ec_priv_encode
  	};
  