/*
 * GnuTLS public key support
 * Copyright (C) 2010-2012 Free Software Foundation, Inc.
 * 
 * Author: Nikos Mavrogiannopoulos
 *
 * The GnuTLS is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 */

#include <gnutls_int.h>
#include <gnutls/pkcs11.h>
#include <stdio.h>
#include <string.h>
#include <gnutls_errors.h>
#include <gnutls_datum.h>
#include <pkcs11_int.h>
#include <gnutls/abstract.h>
#include <gnutls_sig.h>
#include <gnutls_pk.h>
#include <x509_int.h>
#include <openpgp/openpgp_int.h>
#include <gnutls_num.h>
#include <x509/common.h>
#include <x509_b64.h>
#include <abstract_int.h>
#include <fips.h>
#include <gnutls_ecc.h>


#define OPENPGP_KEY_PRIMARY 2
#define OPENPGP_KEY_SUBKEY 1


int pubkey_to_bits(gnutls_pk_algorithm_t pk, gnutls_pk_params_st * params)
{
	switch (pk) {
	case GNUTLS_PK_RSA:
		return _gnutls_mpi_get_nbits(params->params[0]);
	case GNUTLS_PK_DSA:
		return _gnutls_mpi_get_nbits(params->params[3]);
	case GNUTLS_PK_EC:
		return gnutls_ecc_curve_get_size(params->flags) * 8;
	default:
		return 0;
	}
}

/**
 * gnutls_pubkey_get_pk_algorithm:
 * @key: should contain a #gnutls_pubkey_t structure
 * @bits: If set will return the number of bits of the parameters (may be NULL)
 *
 * This function will return the public key algorithm of a public
 * key and if possible will return a number of bits that indicates
 * the security parameter of the key.
 *
 * Returns: a member of the #gnutls_pk_algorithm_t enumeration on
 *   success, or a negative error code on error.
 *
 * Since: 2.12.0
 **/
int gnutls_pubkey_get_pk_algorithm(gnutls_pubkey_t key, unsigned int *bits)
{
	if (bits)
		*bits = key->bits;

	return key->pk_algorithm;
}

/**
 * gnutls_pubkey_get_key_usage:
 * @key: should contain a #gnutls_pubkey_t structure
 * @usage: If set will return the number of bits of the parameters (may be NULL)
 *
 * This function will return the key usage of the public key.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int gnutls_pubkey_get_key_usage(gnutls_pubkey_t key, unsigned int *usage)
{
	if (usage)
		*usage = key->key_usage;

	return 0;
}

/**
 * gnutls_pubkey_init:
 * @key: The structure to be initialized
 *
 * This function will initialize an public key structure.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int gnutls_pubkey_init(gnutls_pubkey_t * key)
{
	FAIL_IF_LIB_ERROR;

	*key = gnutls_calloc(1, sizeof(struct gnutls_pubkey_st));
	if (*key == NULL) {
		gnutls_assert();
		return GNUTLS_E_MEMORY_ERROR;
	}

	return 0;
}

/**
 * gnutls_pubkey_deinit:
 * @key: The structure to be deinitialized
 *
 * This function will deinitialize a public key structure.
 *
 * Since: 2.12.0
 **/
void gnutls_pubkey_deinit(gnutls_pubkey_t key)
{
	if (!key)
		return;
	gnutls_pk_params_release(&key->params);
	gnutls_free(key);
}

/**
 * gnutls_pubkey_import_x509:
 * @key: The public key
 * @crt: The certificate to be imported
 * @flags: should be zero
 *
 * This function will import the given public key to the abstract
 * #gnutls_pubkey_t structure.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_import_x509(gnutls_pubkey_t key, gnutls_x509_crt_t crt,
			  unsigned int flags)
{
	int ret;

	key->pk_algorithm =
	    gnutls_x509_crt_get_pk_algorithm(crt, &key->bits);

	ret = gnutls_x509_crt_get_key_usage(crt, &key->key_usage, NULL);
	if (ret < 0)
		key->key_usage = 0;

	ret = _gnutls_x509_crt_get_mpis(crt, &key->params);
	if (ret < 0) {
		gnutls_assert();
		return ret;
	}

	return 0;
}

/**
 * gnutls_pubkey_import_x509_crq:
 * @key: The public key
 * @crq: The certificate to be imported
 * @flags: should be zero
 *
 * This function will import the given public key to the abstract
 * #gnutls_pubkey_t structure.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 3.1.5
 **/
int
gnutls_pubkey_import_x509_crq(gnutls_pubkey_t key, gnutls_x509_crq_t crq,
			      unsigned int flags)
{
	int ret;

	key->pk_algorithm =
	    gnutls_x509_crq_get_pk_algorithm(crq, &key->bits);

	ret = gnutls_x509_crq_get_key_usage(crq, &key->key_usage, NULL);
	if (ret < 0)
		key->key_usage = 0;

	ret = _gnutls_x509_crq_get_mpis(crq, &key->params);
	if (ret < 0) {
		gnutls_assert();
		return ret;
	}

	return 0;
}

/**
 * gnutls_pubkey_import_privkey:
 * @key: The public key
 * @pkey: The private key
 * @usage: GNUTLS_KEY_* key usage flags.
 * @flags: should be zero
 *
 * Imports the public key from a private.  This function will import
 * the given public key to the abstract #gnutls_pubkey_t structure.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_import_privkey(gnutls_pubkey_t key, gnutls_privkey_t pkey,
			     unsigned int usage, unsigned int flags)
{
	key->pk_algorithm =
	    gnutls_privkey_get_pk_algorithm(pkey, &key->bits);

	key->key_usage = usage;

	return _gnutls_privkey_get_public_mpis(pkey, &key->params);
}

/**
 * gnutls_pubkey_get_preferred_hash_algorithm:
 * @key: Holds the certificate
 * @hash: The result of the call with the hash algorithm used for signature
 * @mand: If non zero it means that the algorithm MUST use this hash. May be NULL.
 *
 * This function will read the certifcate and return the appropriate digest
 * algorithm to use for signing with this certificate. Some certificates (i.e.
 * DSA might not be able to sign without the preferred algorithm).
 *
 * To get the signature algorithm instead of just the hash use gnutls_pk_to_sign()
 * with the algorithm of the certificate/key and the provided @hash.
 *
 * Returns: the 0 if the hash algorithm is found. A negative error code is
 * returned on error.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_get_preferred_hash_algorithm(gnutls_pubkey_t key,
					   gnutls_digest_algorithm_t *
					   hash, unsigned int *mand)
{
	int ret;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	ret = _gnutls_pk_get_hash_algorithm(key->pk_algorithm,
					    &key->params, hash, mand);

	return ret;
}

#ifdef ENABLE_PKCS11

/**
 * gnutls_pubkey_import_pkcs11:
 * @key: The public key
 * @obj: The parameters to be imported
 * @flags: should be zero
 *
 * Imports a public key from a pkcs11 key. This function will import
 * the given public key to the abstract #gnutls_pubkey_t structure.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_import_pkcs11(gnutls_pubkey_t key,
			    gnutls_pkcs11_obj_t obj, unsigned int flags)
{
	int ret, type;

	type = gnutls_pkcs11_obj_get_type(obj);
	if (type != GNUTLS_PKCS11_OBJ_PUBKEY
	    && type != GNUTLS_PKCS11_OBJ_X509_CRT) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	if (type == GNUTLS_PKCS11_OBJ_X509_CRT) {
		gnutls_x509_crt_t xcrt;

		ret = gnutls_x509_crt_init(&xcrt);
		if (ret < 0) {
			gnutls_assert()
			    return ret;
		}

		ret = gnutls_x509_crt_import_pkcs11(xcrt, obj);
		if (ret < 0) {
			gnutls_assert();
			goto cleanup_crt;
		}

		ret = gnutls_pubkey_import_x509(key, xcrt, 0);
		if (ret < 0) {
			gnutls_assert();
			goto cleanup_crt;
		}

		gnutls_x509_crt_get_key_usage(xcrt, &key->key_usage, NULL);

		ret = 0;
	      cleanup_crt:
		gnutls_x509_crt_deinit(xcrt);
		return ret;
	}

	key->key_usage = obj->key_usage;

	switch (obj->pk_algorithm) {
	case GNUTLS_PK_RSA:
		ret = gnutls_pubkey_import_rsa_raw(key, &obj->pubkey[0],
						   &obj->pubkey[1]);
		break;
	case GNUTLS_PK_DSA:
		ret = gnutls_pubkey_import_dsa_raw(key, &obj->pubkey[0],
						   &obj->pubkey[1],
						   &obj->pubkey[2],
						   &obj->pubkey[3]);
		break;
	case GNUTLS_PK_EC:
		ret = gnutls_pubkey_import_ecc_x962(key, &obj->pubkey[0],
						    &obj->pubkey[1]);
		break;
	default:
		gnutls_assert();
		return GNUTLS_E_UNIMPLEMENTED_FEATURE;
	}

	if (ret < 0) {
		gnutls_assert();
		return ret;
	}

	return 0;
}

#endif				/* ENABLE_PKCS11 */

#ifdef ENABLE_OPENPGP

/**
 * gnutls_pubkey_import_openpgp:
 * @key: The public key
 * @crt: The certificate to be imported
 * @flags: should be zero
 *
 * Imports a public key from an openpgp key. This function will import
 * the given public key to the abstract #gnutls_pubkey_t
 * structure. The subkey set as preferred will be imported or the
 * master key otherwise.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_import_openpgp(gnutls_pubkey_t key,
			     gnutls_openpgp_crt_t crt, unsigned int flags)
{
	int ret, idx;
	uint32_t kid32[2];
	uint32_t *k;
	uint8_t keyid[GNUTLS_OPENPGP_KEYID_SIZE];
	size_t len;

	len = sizeof(key->openpgp_key_fpr);
	ret =
	    gnutls_openpgp_crt_get_fingerprint(crt, key->openpgp_key_fpr,
					       &len);
	if (ret < 0)
		return gnutls_assert_val(ret);
	key->openpgp_key_fpr_set = 1;

	ret = gnutls_openpgp_crt_get_preferred_key_id(crt, keyid);
	if (ret == GNUTLS_E_OPENPGP_PREFERRED_KEY_ERROR) {
		key->pk_algorithm =
		    gnutls_openpgp_crt_get_pk_algorithm(crt, &key->bits);
		key->openpgp_key_id_set = OPENPGP_KEY_PRIMARY;

		ret =
		    gnutls_openpgp_crt_get_key_id(crt,
						  key->openpgp_key_id);
		if (ret < 0)
			return gnutls_assert_val(ret);

		ret =
		    gnutls_openpgp_crt_get_key_usage(crt, &key->key_usage);
		if (ret < 0)
			key->key_usage = 0;

		k = NULL;
	} else {
		if (ret < 0) {
			gnutls_assert();
			return ret;
		}
		key->openpgp_key_id_set = OPENPGP_KEY_SUBKEY;

		KEYID_IMPORT(kid32, keyid);
		k = kid32;

		idx = gnutls_openpgp_crt_get_subkey_idx(crt, keyid);

		ret =
		    gnutls_openpgp_crt_get_subkey_id(crt, idx,
						     key->openpgp_key_id);
		if (ret < 0)
			return gnutls_assert_val(ret);

		ret =
		    gnutls_openpgp_crt_get_subkey_usage(crt, idx,
							&key->key_usage);
		if (ret < 0)
			key->key_usage = 0;

		key->pk_algorithm =
		    gnutls_openpgp_crt_get_subkey_pk_algorithm(crt, idx,
							       NULL);
	}

	ret = _gnutls_openpgp_crt_get_mpis(crt, k, &key->params);
	if (ret < 0)
		return gnutls_assert_val(ret);

	return 0;
}

/**
 * gnutls_pubkey_get_openpgp_key_id:
 * @key: Holds the public key
 * @flags: should be 0 or %GNUTLS_PUBKEY_GET_OPENPGP_FINGERPRINT
 * @output_data: will contain the key ID
 * @output_data_size: holds the size of output_data (and will be
 *   replaced by the actual size of parameters)
 * @subkey: Will be non zero if the key ID corresponds to a subkey
 *
 * This function returns the OpenPGP key ID of the corresponding key.
 * The key is a unique ID that depends on the public
 * key parameters. 
 *
 * If the flag %GNUTLS_PUBKEY_GET_OPENPGP_FINGERPRINT is specified
 * this function returns the fingerprint of the master key.
 *
 * If the buffer provided is not long enough to hold the output, then
 * *output_data_size is updated and %GNUTLS_E_SHORT_MEMORY_BUFFER will
 * be returned.  The output is %GNUTLS_OPENPGP_KEYID_SIZE bytes long.
 *
 * Returns: In case of failure a negative error code will be
 *   returned, and 0 on success.
 *
 * Since: 3.0
 **/
int
gnutls_pubkey_get_openpgp_key_id(gnutls_pubkey_t key, unsigned int flags,
				 unsigned char *output_data,
				 size_t * output_data_size,
				 unsigned int *subkey)
{
	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	if (flags & GNUTLS_PUBKEY_GET_OPENPGP_FINGERPRINT) {
		if (*output_data_size < sizeof(key->openpgp_key_fpr)) {
			*output_data_size = sizeof(key->openpgp_key_fpr);
			return
			    gnutls_assert_val
			    (GNUTLS_E_SHORT_MEMORY_BUFFER);
		}

		if (key->openpgp_key_fpr_set == 0)
			return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);

		if (output_data)
			memcpy(output_data, key->openpgp_key_fpr,
			       sizeof(key->openpgp_key_fpr));
		*output_data_size = sizeof(key->openpgp_key_fpr);

		return 0;
	}

	if (*output_data_size < sizeof(key->openpgp_key_id)) {
		*output_data_size = sizeof(key->openpgp_key_id);
		return gnutls_assert_val(GNUTLS_E_SHORT_MEMORY_BUFFER);
	}

	if (key->openpgp_key_id_set == 0)
		return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);

	if (subkey) {
		if (key->openpgp_key_id_set == OPENPGP_KEY_SUBKEY)
			*subkey = 1;
		else
			*subkey = 0;
	}

	if (output_data) {
		memcpy(output_data, key->openpgp_key_id,
		       sizeof(key->openpgp_key_id));
	}
	*output_data_size = sizeof(key->openpgp_key_id);

	return 0;
}

/**
 * gnutls_pubkey_import_openpgp_raw:
 * @pkey: The public key
 * @data: The public key data to be imported
 * @format: The format of the public key
 * @keyid: The key id to use (optional)
 * @flags: Should be zero
 *
 * This function will import the given public key to the abstract
 * #gnutls_pubkey_t structure. 
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 3.1.3
 **/
int gnutls_pubkey_import_openpgp_raw(gnutls_pubkey_t pkey,
				     const gnutls_datum_t * data,
				     gnutls_openpgp_crt_fmt_t format,
				     const gnutls_openpgp_keyid_t keyid,
				     unsigned int flags)
{
	gnutls_openpgp_crt_t xpriv;
	int ret;

	ret = gnutls_openpgp_crt_init(&xpriv);
	if (ret < 0)
		return gnutls_assert_val(ret);

	ret = gnutls_openpgp_crt_import(xpriv, data, format);
	if (ret < 0) {
		gnutls_assert();
		goto cleanup;
	}

	if (keyid) {
		ret =
		    gnutls_openpgp_crt_set_preferred_key_id(xpriv, keyid);
		if (ret < 0) {
			gnutls_assert();
			goto cleanup;
		}
	}

	ret = gnutls_pubkey_import_openpgp(pkey, xpriv, flags);
	if (ret < 0) {
		gnutls_assert();
		goto cleanup;
	}

	ret = 0;

      cleanup:
	gnutls_openpgp_crt_deinit(xpriv);

	return ret;
}

#endif

/**
 * gnutls_pubkey_export:
 * @key: Holds the certificate
 * @format: the format of output params. One of PEM or DER.
 * @output_data: will contain a certificate PEM or DER encoded
 * @output_data_size: holds the size of output_data (and will be
 *   replaced by the actual size of parameters)
 *
 * This function will export the public key to DER or PEM format.
 * The contents of the exported data is the SubjectPublicKeyInfo
 * X.509 structure.
 *
 * If the buffer provided is not long enough to hold the output, then
 * *output_data_size is updated and %GNUTLS_E_SHORT_MEMORY_BUFFER will
 * be returned.
 *
 * If the structure is PEM encoded, it will have a header
 * of "BEGIN CERTIFICATE".
 *
 * Returns: In case of failure a negative error code will be
 *   returned, and 0 on success.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_export(gnutls_pubkey_t key,
		     gnutls_x509_crt_fmt_t format, void *output_data,
		     size_t * output_data_size)
{
	int result;
	ASN1_TYPE spk = ASN1_TYPE_EMPTY;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	if ((result = asn1_create_element
	     (_gnutls_get_pkix(), "PKIX1.SubjectPublicKeyInfo", &spk))
	    != ASN1_SUCCESS) {
		gnutls_assert();
		return _gnutls_asn2err(result);
	}

	result =
	    _gnutls_x509_encode_and_copy_PKI_params(spk, "",
						    key->pk_algorithm,
						    &key->params);
	if (result < 0) {
		gnutls_assert();
		goto cleanup;
	}

	result = _gnutls_x509_export_int_named(spk, "",
					       format, PEM_PK,
					       output_data,
					       output_data_size);
	if (result < 0) {
		gnutls_assert();
		goto cleanup;
	}

	result = 0;

      cleanup:
	asn1_delete_structure(&spk);

	return result;
}

/**
 * gnutls_pubkey_export2:
 * @key: Holds the certificate
 * @format: the format of output params. One of PEM or DER.
 * @out: will contain a certificate PEM or DER encoded
 *
 * This function will export the public key to DER or PEM format.
 * The contents of the exported data is the SubjectPublicKeyInfo
 * X.509 structure.
 *
 * The output buffer will be allocated using gnutls_malloc().
 *
 * If the structure is PEM encoded, it will have a header
 * of "BEGIN CERTIFICATE".
 *
 * Returns: In case of failure a negative error code will be
 *   returned, and 0 on success.
 *
 * Since: 3.1.3
 **/
int
gnutls_pubkey_export2(gnutls_pubkey_t key,
		      gnutls_x509_crt_fmt_t format, gnutls_datum_t * out)
{
	int result;
	ASN1_TYPE spk = ASN1_TYPE_EMPTY;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	if ((result = asn1_create_element
	     (_gnutls_get_pkix(), "PKIX1.SubjectPublicKeyInfo", &spk))
	    != ASN1_SUCCESS) {
		gnutls_assert();
		return _gnutls_asn2err(result);
	}

	result =
	    _gnutls_x509_encode_and_copy_PKI_params(spk, "",
						    key->pk_algorithm,
						    &key->params);
	if (result < 0) {
		gnutls_assert();
		goto cleanup;
	}

	result = _gnutls_x509_export_int_named2(spk, "",
						format, PEM_PK,
						out);
	if (result < 0) {
		gnutls_assert();
		goto cleanup;
	}

	result = 0;

      cleanup:
	asn1_delete_structure(&spk);

	return result;
}

/**
 * gnutls_pubkey_get_key_id:
 * @key: Holds the public key
 * @flags: should be 0 for now
 * @output_data: will contain the key ID
 * @output_data_size: holds the size of output_data (and will be
 *   replaced by the actual size of parameters)
 *
 * This function will return a unique ID that depends on the public
 * key parameters. This ID can be used in checking whether a
 * certificate corresponds to the given public key.
 *
 * If the buffer provided is not long enough to hold the output, then
 * *output_data_size is updated and %GNUTLS_E_SHORT_MEMORY_BUFFER will
 * be returned.  The output will normally be a SHA-1 hash output,
 * which is 20 bytes.
 *
 * Returns: In case of failure a negative error code will be
 *   returned, and 0 on success.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_get_key_id(gnutls_pubkey_t key, unsigned int flags,
			 unsigned char *output_data,
			 size_t * output_data_size)
{
	int ret = 0;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	ret =
	    _gnutls_get_key_id(key->pk_algorithm, &key->params,
			       output_data, output_data_size);
	if (ret < 0) {
		gnutls_assert();
		return ret;
	}

	return 0;
}

/**
 * gnutls_pubkey_export_rsa_raw:
 * @key: Holds the certificate
 * @m: will hold the modulus
 * @e: will hold the public exponent
 *
 * This function will export the RSA public key's parameters found in
 * the given structure.  The new parameters will be allocated using
 * gnutls_malloc() and will be stored in the appropriate datum.
 *
 * Returns: %GNUTLS_E_SUCCESS on success, otherwise a negative error code.
 *
 * Since: 3.3.0
 **/
int
gnutls_pubkey_export_rsa_raw(gnutls_pubkey_t key,
			     gnutls_datum_t * m, gnutls_datum_t * e)
{
	int ret;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	if (key->pk_algorithm != GNUTLS_PK_RSA) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	ret = _gnutls_mpi_dprint_lz(key->params.params[0], m);
	if (ret < 0) {
		gnutls_assert();
		return ret;
	}

	ret = _gnutls_mpi_dprint_lz(key->params.params[1], e);
	if (ret < 0) {
		gnutls_assert();
		_gnutls_free_datum(m);
		return ret;
	}

	return 0;
}


/**
 * gnutls_pubkey_export_dsa_raw:
 * @key: Holds the public key
 * @p: will hold the p
 * @q: will hold the q
 * @g: will hold the g
 * @y: will hold the y
 *
 * This function will export the DSA public key's parameters found in
 * the given certificate.  The new parameters will be allocated using
 * gnutls_malloc() and will be stored in the appropriate datum.
 *
 * Returns: %GNUTLS_E_SUCCESS on success, otherwise a negative error code.
 *
 * Since: 3.3.0
 **/
int
gnutls_pubkey_export_dsa_raw(gnutls_pubkey_t key,
			     gnutls_datum_t * p, gnutls_datum_t * q,
			     gnutls_datum_t * g, gnutls_datum_t * y)
{
	int ret;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	if (key->pk_algorithm != GNUTLS_PK_DSA) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	/* P */
	ret = _gnutls_mpi_dprint_lz(key->params.params[0], p);
	if (ret < 0) {
		gnutls_assert();
		return ret;
	}

	/* Q */
	ret = _gnutls_mpi_dprint_lz(key->params.params[1], q);
	if (ret < 0) {
		gnutls_assert();
		_gnutls_free_datum(p);
		return ret;
	}


	/* G */
	ret = _gnutls_mpi_dprint_lz(key->params.params[2], g);
	if (ret < 0) {
		gnutls_assert();
		_gnutls_free_datum(p);
		_gnutls_free_datum(q);
		return ret;
	}


	/* Y */
	ret = _gnutls_mpi_dprint_lz(key->params.params[3], y);
	if (ret < 0) {
		gnutls_assert();
		_gnutls_free_datum(p);
		_gnutls_free_datum(g);
		_gnutls_free_datum(q);
		return ret;
	}

	return 0;
}

/**
 * gnutls_pubkey_export_ecc_raw:
 * @key: Holds the public key
 * @curve: will hold the curve
 * @x: will hold x
 * @y: will hold y
 *
 * This function will export the ECC public key's parameters found in
 * the given certificate.  The new parameters will be allocated using
 * gnutls_malloc() and will be stored in the appropriate datum.
 *
 * Returns: %GNUTLS_E_SUCCESS on success, otherwise a negative error code.
 *
 * Since: 3.0
 **/
int
gnutls_pubkey_export_ecc_raw(gnutls_pubkey_t key,
			     gnutls_ecc_curve_t * curve,
			     gnutls_datum_t * x, gnutls_datum_t * y)
{
	int ret;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	if (key->pk_algorithm != GNUTLS_PK_EC) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	*curve = key->params.flags;

	/* X */
	ret = _gnutls_mpi_dprint_lz(key->params.params[ECC_X], x);
	if (ret < 0) {
		gnutls_assert();
		return ret;
	}

	/* Y */
	ret = _gnutls_mpi_dprint_lz(key->params.params[ECC_Y], y);
	if (ret < 0) {
		gnutls_assert();
		_gnutls_free_datum(x);
		return ret;
	}

	return 0;
}

/**
 * gnutls_pubkey_export_ecc_x962:
 * @key: Holds the public key
 * @parameters: DER encoding of an ANSI X9.62 parameters
 * @ecpoint: DER encoding of ANSI X9.62 ECPoint
 *
 * This function will export the ECC public key's parameters found in
 * the given certificate.  The new parameters will be allocated using
 * gnutls_malloc() and will be stored in the appropriate datum.
 *
 * Returns: %GNUTLS_E_SUCCESS on success, otherwise a negative error code.
 *
 * Since: 3.3.0
 **/
int gnutls_pubkey_export_ecc_x962(gnutls_pubkey_t key,
				  gnutls_datum_t * parameters,
				  gnutls_datum_t * ecpoint)
{
	int ret;

	if (key == NULL || key->pk_algorithm != GNUTLS_PK_EC)
		return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);

	ret = _gnutls_x509_write_ecc_pubkey(&key->params, ecpoint);
	if (ret < 0)
		return gnutls_assert_val(ret);

	ret = _gnutls_x509_write_ecc_params(&key->params, parameters);
	if (ret < 0) {
		_gnutls_free_datum(ecpoint);
		return gnutls_assert_val(ret);
	}

	return 0;
}

/**
 * gnutls_pubkey_import:
 * @key: The structure to store the parsed public key. 
 * @data: The DER or PEM encoded certificate. 
 * @format: One of DER or PEM 
 * 
 * This function will import the provided public key in
 * a SubjectPublicKeyInfo X.509 structure to a native
 * %gnutls_pubkey_t structure. The output will be stored 
 * in @key. If the public key is PEM encoded it should have a header 
 * of "PUBLIC KEY". 
 * 
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 * negative error value.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_import(gnutls_pubkey_t key,
		     const gnutls_datum_t * data,
		     gnutls_x509_crt_fmt_t format)
{
	int result = 0, need_free = 0;
	gnutls_datum_t _data;
	ASN1_TYPE spk;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	_data.data = data->data;
	_data.size = data->size;

	/* If the Certificate is in PEM format then decode it
	 */
	if (format == GNUTLS_X509_FMT_PEM) {
		/* Try the first header */
		result =
		    _gnutls_fbase64_decode(PEM_PK, data->data,
					   data->size, &_data);

		if (result < 0) {
			gnutls_assert();
			return result;
		}

		need_free = 1;
	}

	if ((result = asn1_create_element
	     (_gnutls_get_pkix(), "PKIX1.SubjectPublicKeyInfo", &spk))
	    != ASN1_SUCCESS) {
		gnutls_assert();
		result = _gnutls_asn2err(result);
		goto cleanup;
	}

	result = asn1_der_decoding(&spk, _data.data, _data.size, NULL);
	if (result != ASN1_SUCCESS) {
		gnutls_assert();
		result = _gnutls_asn2err(result);
		goto cleanup;
	}

	result = _gnutls_get_asn_mpis(spk, "", &key->params);
	if (result < 0) {
		gnutls_assert();
		goto cleanup;
	}

	/* this has already been called by get_asn_mpis() thus it cannot
	 * fail.
	 */
	key->pk_algorithm = _gnutls_x509_get_pk_algorithm(spk, "", NULL);
	key->bits = pubkey_to_bits(key->pk_algorithm, &key->params);

	result = 0;

      cleanup:
	asn1_delete_structure(&spk);

	if (need_free)
		_gnutls_free_datum(&_data);
	return result;
}

/**
 * gnutls_x509_crt_set_pubkey:
 * @crt: should contain a #gnutls_x509_crt_t structure
 * @key: holds a public key
 *
 * This function will set the public parameters from the given public
 * key to the request.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int gnutls_x509_crt_set_pubkey(gnutls_x509_crt_t crt, gnutls_pubkey_t key)
{
	int result;

	if (crt == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	result = _gnutls_x509_encode_and_copy_PKI_params(crt->cert,
							 "tbsCertificate.subjectPublicKeyInfo",
							 key->pk_algorithm,
							 &key->params);

	if (result < 0) {
		gnutls_assert();
		return result;
	}

	if (key->key_usage)
		gnutls_x509_crt_set_key_usage(crt, key->key_usage);

	return 0;
}

/**
 * gnutls_x509_crq_set_pubkey:
 * @crq: should contain a #gnutls_x509_crq_t structure
 * @key: holds a public key
 *
 * This function will set the public parameters from the given public
 * key to the request.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int gnutls_x509_crq_set_pubkey(gnutls_x509_crq_t crq, gnutls_pubkey_t key)
{
	int result;

	if (crq == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	result = _gnutls_x509_encode_and_copy_PKI_params
	    (crq->crq,
	     "certificationRequestInfo.subjectPKInfo",
	     key->pk_algorithm, &key->params);

	if (result < 0) {
		gnutls_assert();
		return result;
	}

	if (key->key_usage)
		gnutls_x509_crq_set_key_usage(crq, key->key_usage);

	return 0;
}

/**
 * gnutls_pubkey_set_key_usage:
 * @key: a certificate of type #gnutls_x509_crt_t
 * @usage: an ORed sequence of the GNUTLS_KEY_* elements.
 *
 * This function will set the key usage flags of the public key. This
 * is only useful if the key is to be exported to a certificate or
 * certificate request.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int gnutls_pubkey_set_key_usage(gnutls_pubkey_t key, unsigned int usage)
{
	key->key_usage = usage;

	return 0;
}

#ifdef ENABLE_PKCS11

/**
 * gnutls_pubkey_import_pkcs11_url:
 * @key: A key of type #gnutls_pubkey_t
 * @url: A PKCS 11 url
 * @flags: One of GNUTLS_PKCS11_OBJ_* flags
 *
 * This function will import a PKCS 11 certificate to a #gnutls_pubkey_t
 * structure.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_import_pkcs11_url(gnutls_pubkey_t key, const char *url,
				unsigned int flags)
{
	gnutls_pkcs11_obj_t pcrt;
	int ret;

	ret = gnutls_pkcs11_obj_init(&pcrt);
	if (ret < 0) {
		gnutls_assert();
		return ret;
	}

	if (key->pin.cb)
		gnutls_pkcs11_obj_set_pin_function(pcrt, key->pin.cb,
						   key->pin.data);

	ret = gnutls_pkcs11_obj_import_url(pcrt, url, flags);
	if (ret < 0) {
		gnutls_assert();
		goto cleanup;
	}

	ret = gnutls_pubkey_import_pkcs11(key, pcrt, 0);
	if (ret < 0) {
		gnutls_assert();
		goto cleanup;
	}

	ret = 0;
      cleanup:

	gnutls_pkcs11_obj_deinit(pcrt);

	return ret;
}

#endif				/* ENABLE_PKCS11 */

/**
 * gnutls_pubkey_import_url:
 * @key: A key of type #gnutls_pubkey_t
 * @url: A PKCS 11 url
 * @flags: One of GNUTLS_PKCS11_OBJ_* flags
 *
 * This function will import a PKCS11 certificate or a TPM key 
 * as a public key.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 3.1.0
 **/
int
gnutls_pubkey_import_url(gnutls_pubkey_t key, const char *url,
			 unsigned int flags)
{
	if (strncmp(url, "pkcs11:", 7) == 0)
#ifdef ENABLE_PKCS11
		return gnutls_pubkey_import_pkcs11_url(key, url, flags);
#else
		return gnutls_assert_val(GNUTLS_E_UNIMPLEMENTED_FEATURE);
#endif

	if (strncmp(url, "tpmkey:", 7) == 0)
#ifdef HAVE_TROUSERS
		return gnutls_pubkey_import_tpm_url(key, url, NULL, 0);
#else
		return gnutls_assert_val(GNUTLS_E_UNIMPLEMENTED_FEATURE);
#endif

	return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);
}

/**
 * gnutls_pubkey_import_rsa_raw:
 * @key: Is a structure will hold the parameters
 * @m: holds the modulus
 * @e: holds the public exponent
 *
 * This function will replace the parameters in the given structure.
 * The new parameters should be stored in the appropriate
 * gnutls_datum.
 *
 * Returns: %GNUTLS_E_SUCCESS on success, or an negative error code.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_import_rsa_raw(gnutls_pubkey_t key,
			     const gnutls_datum_t * m,
			     const gnutls_datum_t * e)
{
	size_t siz = 0;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	gnutls_pk_params_init(&key->params);

	siz = m->size;
	if (_gnutls_mpi_init_scan_nz(&key->params.params[0], m->data, siz)) {
		gnutls_assert();
		return GNUTLS_E_MPI_SCAN_FAILED;
	}

	siz = e->size;
	if (_gnutls_mpi_init_scan_nz(&key->params.params[1], e->data, siz)) {
		gnutls_assert();
		_gnutls_mpi_release(&key->params.params[0]);
		return GNUTLS_E_MPI_SCAN_FAILED;
	}

	key->params.params_nr = RSA_PUBLIC_PARAMS;
	key->pk_algorithm = GNUTLS_PK_RSA;
	key->bits = pubkey_to_bits(GNUTLS_PK_RSA, &key->params);

	return 0;
}

/**
 * gnutls_pubkey_import_ecc_raw:
 * @key: The structure to store the parsed key
 * @curve: holds the curve
 * @x: holds the x
 * @y: holds the y
 *
 * This function will convert the given elliptic curve parameters to a
 * #gnutls_pubkey_t.  The output will be stored in @key.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 3.0
 **/
int
gnutls_pubkey_import_ecc_raw(gnutls_pubkey_t key,
			     gnutls_ecc_curve_t curve,
			     const gnutls_datum_t * x,
			     const gnutls_datum_t * y)
{
	int ret;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	key->params.flags = curve;

	if (_gnutls_mpi_init_scan_nz
	    (&key->params.params[ECC_X], x->data, x->size)) {
		gnutls_assert();
		ret = GNUTLS_E_MPI_SCAN_FAILED;
		goto cleanup;
	}
	key->params.params_nr++;

	if (_gnutls_mpi_init_scan_nz
	    (&key->params.params[ECC_Y], y->data, y->size)) {
		gnutls_assert();
		ret = GNUTLS_E_MPI_SCAN_FAILED;
		goto cleanup;
	}
	key->params.params_nr++;
	key->pk_algorithm = GNUTLS_PK_EC;

	return 0;

      cleanup:
	gnutls_pk_params_release(&key->params);
	return ret;
}

/**
 * gnutls_pubkey_import_ecc_x962:
 * @key: The structure to store the parsed key
 * @parameters: DER encoding of an ANSI X9.62 parameters
 * @ecpoint: DER encoding of ANSI X9.62 ECPoint
 *
 * This function will convert the given elliptic curve parameters to a
 * #gnutls_pubkey_t.  The output will be stored in @key.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 3.0
 **/
int
gnutls_pubkey_import_ecc_x962(gnutls_pubkey_t key,
			      const gnutls_datum_t * parameters,
			      const gnutls_datum_t * ecpoint)
{
	int ret;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	key->params.params_nr = 0;

	ret =
	    _gnutls_x509_read_ecc_params(parameters->data,
					 parameters->size, &key->params);
	if (ret < 0) {
		gnutls_assert();
		goto cleanup;
	}

	ret = _gnutls_ecc_ansi_x963_import(ecpoint->data, ecpoint->size,
					   &key->params.params[ECC_X],
					   &key->params.params[ECC_Y]);
	if (ret < 0) {
		gnutls_assert();
		goto cleanup;
	}
	key->params.params_nr += 2;
	key->pk_algorithm = GNUTLS_PK_EC;

	return 0;

      cleanup:
	gnutls_pk_params_release(&key->params);
	return ret;
}

/**
 * gnutls_pubkey_import_dsa_raw:
 * @key: The structure to store the parsed key
 * @p: holds the p
 * @q: holds the q
 * @g: holds the g
 * @y: holds the y
 *
 * This function will convert the given DSA raw parameters to the
 * native #gnutls_pubkey_t format.  The output will be stored
 * in @key.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_import_dsa_raw(gnutls_pubkey_t key,
			     const gnutls_datum_t * p,
			     const gnutls_datum_t * q,
			     const gnutls_datum_t * g,
			     const gnutls_datum_t * y)
{
	size_t siz = 0;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	gnutls_pk_params_init(&key->params);

	siz = p->size;
	if (_gnutls_mpi_init_scan_nz(&key->params.params[0], p->data, siz)) {
		gnutls_assert();
		return GNUTLS_E_MPI_SCAN_FAILED;
	}

	siz = q->size;
	if (_gnutls_mpi_init_scan_nz(&key->params.params[1], q->data, siz)) {
		gnutls_assert();
		_gnutls_mpi_release(&key->params.params[0]);
		return GNUTLS_E_MPI_SCAN_FAILED;
	}

	siz = g->size;
	if (_gnutls_mpi_init_scan_nz(&key->params.params[2], g->data, siz)) {
		gnutls_assert();
		_gnutls_mpi_release(&key->params.params[1]);
		_gnutls_mpi_release(&key->params.params[0]);
		return GNUTLS_E_MPI_SCAN_FAILED;
	}

	siz = y->size;
	if (_gnutls_mpi_init_scan_nz(&key->params.params[3], y->data, siz)) {
		gnutls_assert();
		_gnutls_mpi_release(&key->params.params[2]);
		_gnutls_mpi_release(&key->params.params[1]);
		_gnutls_mpi_release(&key->params.params[0]);
		return GNUTLS_E_MPI_SCAN_FAILED;
	}

	key->params.params_nr = DSA_PUBLIC_PARAMS;
	key->pk_algorithm = GNUTLS_PK_DSA;
	key->bits = pubkey_to_bits(GNUTLS_PK_DSA, &key->params);

	return 0;

}

/**
 * gnutls_pubkey_verify_data:
 * @pubkey: Holds the public key
 * @flags: Zero or one of %gnutls_pubkey_flags_t
 * @data: holds the signed data
 * @signature: contains the signature
 *
 * This function will verify the given signed data, using the
 * parameters from the certificate.
 *
 * Deprecated. This function cannot be easily used securely. 
 * Use gnutls_pubkey_verify_data2() instead.
 *
 * Returns: In case of a verification failure %GNUTLS_E_PK_SIG_VERIFY_FAILED 
 * is returned, and zero or positive code on success. 
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_verify_data(gnutls_pubkey_t pubkey, unsigned int flags,
			  const gnutls_datum_t * data,
			  const gnutls_datum_t * signature)
{
	int ret;
	gnutls_digest_algorithm_t hash;

	if (pubkey == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	if (flags & GNUTLS_PUBKEY_VERIFY_FLAG_TLS1_RSA)
		return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);

	ret = gnutls_pubkey_get_verify_algorithm(pubkey, signature, &hash);
	if (ret < 0)
		return gnutls_assert_val(ret);

	ret = pubkey_verify_data(pubkey->pk_algorithm, mac_to_entry(hash),
				 data, signature, &pubkey->params);
	if (ret < 0) {
		gnutls_assert();
	}

	return ret;
}

/**
 * gnutls_pubkey_verify_data2:
 * @pubkey: Holds the public key
 * @algo: The signature algorithm used
 * @flags: Zero or one of %gnutls_pubkey_flags_t
 * @data: holds the signed data
 * @signature: contains the signature
 *
 * This function will verify the given signed data, using the
 * parameters from the certificate.
 *
 * Returns: In case of a verification failure %GNUTLS_E_PK_SIG_VERIFY_FAILED 
 * is returned, and zero or positive code on success.
 *
 * Since: 3.0
 **/
int
gnutls_pubkey_verify_data2(gnutls_pubkey_t pubkey,
			   gnutls_sign_algorithm_t algo,
			   unsigned int flags,
			   const gnutls_datum_t * data,
			   const gnutls_datum_t * signature)
{
	int ret;
	const mac_entry_st *me;

	if (pubkey == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	if (flags & GNUTLS_PUBKEY_VERIFY_FLAG_TLS1_RSA)
		return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);

	me = mac_to_entry(gnutls_sign_get_hash_algorithm(algo));
	ret = pubkey_verify_data(pubkey->pk_algorithm, me,
				 data, signature, &pubkey->params);
	if (ret < 0) {
		gnutls_assert();
	}

	return ret;
}


/**
 * gnutls_pubkey_verify_hash:
 * @key: Holds the public key
 * @flags: Zero or one of %gnutls_pubkey_flags_t
 * @hash: holds the hash digest to be verified
 * @signature: contains the signature
 *
 * This function will verify the given signed digest, using the
 * parameters from the public key. 
 *
 * Deprecated. This function cannot be easily used securely. 
 * Use gnutls_pubkey_verify_hash2() instead.
 *
 * Returns: In case of a verification failure %GNUTLS_E_PK_SIG_VERIFY_FAILED 
 * is returned, and zero or positive code on success.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_verify_hash(gnutls_pubkey_t key, unsigned int flags,
			  const gnutls_datum_t * hash,
			  const gnutls_datum_t * signature)
{
	gnutls_digest_algorithm_t algo;
	int ret;

	ret = gnutls_pubkey_get_verify_algorithm(key, signature, &algo);
	if (ret < 0)
		return gnutls_assert_val(ret);

	return gnutls_pubkey_verify_hash2(key,
					  gnutls_pk_to_sign(key->
							    pk_algorithm,
							    algo), flags,
					  hash, signature);
}

/**
 * gnutls_pubkey_verify_hash2:
 * @key: Holds the public key
 * @algo: The signature algorithm used
 * @flags: Zero or one of %gnutls_pubkey_flags_t
 * @hash: holds the hash digest to be verified
 * @signature: contains the signature
 *
 * This function will verify the given signed digest, using the
 * parameters from the public key.
 *
 * Returns: In case of a verification failure %GNUTLS_E_PK_SIG_VERIFY_FAILED 
 * is returned, and zero or positive code on success.
 *
 * Since: 3.0
 **/
int
gnutls_pubkey_verify_hash2(gnutls_pubkey_t key,
			   gnutls_sign_algorithm_t algo,
			   unsigned int flags,
			   const gnutls_datum_t * hash,
			   const gnutls_datum_t * signature)
{
	const mac_entry_st *me;

	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	if (flags & GNUTLS_PUBKEY_VERIFY_FLAG_TLS1_RSA) {
		return _gnutls_pk_verify(GNUTLS_PK_RSA, hash, signature,
					 &key->params);
	} else {
		me = mac_to_entry(gnutls_sign_get_hash_algorithm(algo));
		return pubkey_verify_hashed_data(key->pk_algorithm, me,
						 hash, signature,
						 &key->params);
	}
}

/**
 * gnutls_pubkey_encrypt_data:
 * @key: Holds the public key
 * @flags: should be 0 for now
 * @plaintext: The data to be encrypted
 * @ciphertext: contains the encrypted data
 *
 * This function will encrypt the given data, using the public
 * key.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 3.0
 **/
int
gnutls_pubkey_encrypt_data(gnutls_pubkey_t key, unsigned int flags,
			   const gnutls_datum_t * plaintext,
			   gnutls_datum_t * ciphertext)
{
	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	return _gnutls_pk_encrypt(key->pk_algorithm, ciphertext,
				  plaintext, &key->params);
}

/**
 * gnutls_pubkey_get_verify_algorithm:
 * @key: Holds the certificate
 * @signature: contains the signature
 * @hash: The result of the call with the hash algorithm used for signature
 *
 * This function will read the certifcate and the signed data to
 * determine the hash algorithm used to generate the signature.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 2.12.0
 **/
int
gnutls_pubkey_get_verify_algorithm(gnutls_pubkey_t key,
				   const gnutls_datum_t * signature,
				   gnutls_digest_algorithm_t * hash)
{
	if (key == NULL) {
		gnutls_assert();
		return GNUTLS_E_INVALID_REQUEST;
	}

	return _gnutls_x509_verify_algorithm(hash, signature,
					     key->pk_algorithm,
					     &key->params);

}

/* Checks whether the public key given is compatible with the
 * signature algorithm used. The session is only used for audit logging, and
 * it may be null.
 */
int _gnutls_pubkey_compatible_with_sig(gnutls_session_t session,
				       gnutls_pubkey_t pubkey,
				       const version_entry_st * ver,
				       gnutls_sign_algorithm_t sign)
{
	unsigned int hash_size;
	unsigned int sig_hash_size;
	const mac_entry_st *me;

	if (pubkey->pk_algorithm == GNUTLS_PK_DSA) {
		me = _gnutls_dsa_q_to_hash(pubkey->pk_algorithm,
					   &pubkey->params, &hash_size);

		/* DSA keys over 1024 bits cannot be used with TLS 1.x, x<2 */
		if (!_gnutls_version_has_selectable_sighash(ver)) {
			if (me->id != GNUTLS_MAC_SHA1)
				return
				    gnutls_assert_val
				    (GNUTLS_E_INCOMPAT_DSA_KEY_WITH_TLS_PROTOCOL);
		} else if (sign != GNUTLS_SIGN_UNKNOWN) {
			me = mac_to_entry(gnutls_sign_get_hash_algorithm
					  (sign));
			sig_hash_size = _gnutls_hash_get_algo_len(me);
			if (sig_hash_size < hash_size)
				_gnutls_audit_log(session,
						  "The hash size used in signature (%u) is less than the expected (%u)\n",
						  sig_hash_size,
						  hash_size);
		}

	} else if (pubkey->pk_algorithm == GNUTLS_PK_EC) {
		if (_gnutls_version_has_selectable_sighash(ver)
		    && sign != GNUTLS_SIGN_UNKNOWN) {
			me = _gnutls_dsa_q_to_hash(pubkey->pk_algorithm,
						   &pubkey->params,
						   &hash_size);

			me = mac_to_entry(gnutls_sign_get_hash_algorithm
					  (sign));
			sig_hash_size = _gnutls_hash_get_algo_len(me);

			if (sig_hash_size < hash_size)
				_gnutls_audit_log(session,
						  "The hash size used in signature (%u) is less than the expected (%u)\n",
						  sig_hash_size,
						  hash_size);
		}

	}

	return 0;
}

/* Returns the public key. 
 */
int
_gnutls_pubkey_get_mpis(gnutls_pubkey_t key, gnutls_pk_params_st * params)
{
	return _gnutls_pk_params_copy(params, &key->params);
}

/* if hash==MD5 then we do RSA-MD5
 * if hash==SHA then we do RSA-SHA
 * params[0] is modulus
 * params[1] is public key
 */
static int
_pkcs1_rsa_verify_sig(const mac_entry_st * me,
		      const gnutls_datum_t * text,
		      const gnutls_datum_t * prehash,
		      const gnutls_datum_t * signature,
		      gnutls_pk_params_st * params)
{
	int ret;
	uint8_t md[MAX_HASH_SIZE], *cmp;
	unsigned int digest_size;
	gnutls_datum_t d, di;
	digest_hd_st hd;

	digest_size = _gnutls_hash_get_algo_len(me);
	if (prehash) {
		if (prehash->data == NULL || prehash->size != digest_size)
			return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);

		cmp = prehash->data;
	} else {
		if (!text) {
			gnutls_assert();
			return GNUTLS_E_INVALID_REQUEST;
		}

		ret = _gnutls_hash_init(&hd, me);
		if (ret < 0) {
			gnutls_assert();
			return ret;
		}

		_gnutls_hash(&hd, text->data, text->size);
		_gnutls_hash_deinit(&hd, md);

		cmp = md;
	}

	d.data = cmp;
	d.size = digest_size;

	/* decrypted is a BER encoded data of type DigestInfo
	 */
	ret = encode_ber_digest_info(me, &d, &di);
	if (ret < 0)
		return gnutls_assert_val(ret);

	ret = _gnutls_pk_verify(GNUTLS_PK_RSA, &di, signature, params);
	_gnutls_free_datum(&di);

	return ret;
}

/* Hashes input data and verifies a signature.
 */
static int
dsa_verify_hashed_data(gnutls_pk_algorithm_t pk,
		       const mac_entry_st * algo,
		       const gnutls_datum_t * hash,
		       const gnutls_datum_t * signature,
		       gnutls_pk_params_st * params)
{
	gnutls_datum_t digest;
	unsigned int hash_len;

	if (algo == NULL)
		algo = _gnutls_dsa_q_to_hash(pk, params, &hash_len);
	else
		hash_len = _gnutls_hash_get_algo_len(algo);

	/* SHA1 or better allowed */
	if (!hash->data || hash->size < hash_len) {
		gnutls_assert();
		_gnutls_debug_log
		    ("Hash size (%d) does not correspond to hash %s(%d) or better.\n",
		     (int) hash->size, _gnutls_mac_get_name(algo),
		     hash_len);

		if (hash->size != 20)	/* SHA1 is allowed */
			return
			    gnutls_assert_val
			    (GNUTLS_E_PK_SIG_VERIFY_FAILED);
	}

	digest.data = hash->data;
	digest.size = hash->size;

	return _gnutls_pk_verify(pk, &digest, signature, params);
}

static int
dsa_verify_data(gnutls_pk_algorithm_t pk,
		const mac_entry_st * algo,
		const gnutls_datum_t * data,
		const gnutls_datum_t * signature,
		gnutls_pk_params_st * params)
{
	int ret;
	uint8_t _digest[MAX_HASH_SIZE];
	gnutls_datum_t digest;
	digest_hd_st hd;

	if (algo == NULL)
		algo = _gnutls_dsa_q_to_hash(pk, params, NULL);

	ret = _gnutls_hash_init(&hd, algo);
	if (ret < 0)
		return gnutls_assert_val(ret);

	_gnutls_hash(&hd, data->data, data->size);
	_gnutls_hash_deinit(&hd, _digest);

	digest.data = _digest;
	digest.size = _gnutls_hash_get_algo_len(algo);

	return _gnutls_pk_verify(pk, &digest, signature, params);
}

/* Verifies the signature data, and returns GNUTLS_E_PK_SIG_VERIFY_FAILED if 
 * not verified, or 1 otherwise.
 */
int
pubkey_verify_hashed_data(gnutls_pk_algorithm_t pk,
			  const mac_entry_st * hash_algo,
			  const gnutls_datum_t * hash,
			  const gnutls_datum_t * signature,
			  gnutls_pk_params_st * issuer_params)
{

	switch (pk) {
	case GNUTLS_PK_RSA:

		if (_pkcs1_rsa_verify_sig
		    (hash_algo, NULL, hash, signature, issuer_params) != 0)
		{
			gnutls_assert();
			return GNUTLS_E_PK_SIG_VERIFY_FAILED;
		}

		return 1;
		break;

	case GNUTLS_PK_EC:
	case GNUTLS_PK_DSA:
		if (dsa_verify_hashed_data
		    (pk, hash_algo, hash, signature, issuer_params) != 0) {
			gnutls_assert();
			return GNUTLS_E_PK_SIG_VERIFY_FAILED;
		}

		return 1;
		break;
	default:
		gnutls_assert();
		return GNUTLS_E_INTERNAL_ERROR;

	}
}

/* Verifies the signature data, and returns GNUTLS_E_PK_SIG_VERIFY_FAILED if 
 * not verified, or 1 otherwise.
 */
int
pubkey_verify_data(gnutls_pk_algorithm_t pk,
		   const mac_entry_st * me,
		   const gnutls_datum_t * data,
		   const gnutls_datum_t * signature,
		   gnutls_pk_params_st * issuer_params)
{

	switch (pk) {
	case GNUTLS_PK_RSA:

		if (_pkcs1_rsa_verify_sig
		    (me, data, NULL, signature, issuer_params) != 0) {
			gnutls_assert();
			return GNUTLS_E_PK_SIG_VERIFY_FAILED;
		}

		return 1;
		break;

	case GNUTLS_PK_EC:
	case GNUTLS_PK_DSA:
		if (dsa_verify_data(pk, me, data, signature, issuer_params)
		    != 0) {
			gnutls_assert();
			return GNUTLS_E_PK_SIG_VERIFY_FAILED;
		}

		return 1;
		break;
	default:
		gnutls_assert();
		return GNUTLS_E_INTERNAL_ERROR;

	}
}

const mac_entry_st *_gnutls_dsa_q_to_hash(gnutls_pk_algorithm_t algo,
					  const gnutls_pk_params_st *
					  params, unsigned int *hash_len)
{
	int bits = 0;
	int ret;

	if (algo == GNUTLS_PK_DSA)
		bits = _gnutls_mpi_get_nbits(params->params[1]);
	else if (algo == GNUTLS_PK_EC)
		bits = gnutls_ecc_curve_get_size(params->flags) * 8;

	if (bits <= 160) {
		if (hash_len)
			*hash_len = 20;
		ret = GNUTLS_DIG_SHA1;
	} else if (bits <= 192) {
		if (hash_len)
			*hash_len = 24;
		ret = GNUTLS_DIG_SHA256;
	} else if (bits <= 224) {
		if (hash_len)
			*hash_len = 28;
		ret = GNUTLS_DIG_SHA256;
	} else if (bits <= 256) {
		if (hash_len)
			*hash_len = 32;
		ret = GNUTLS_DIG_SHA256;
	} else if (bits <= 384) {
		if (hash_len)
			*hash_len = 48;
		ret = GNUTLS_DIG_SHA384;
	} else {
		if (hash_len)
			*hash_len = 64;
		ret = GNUTLS_DIG_SHA512;
	}

	return mac_to_entry(ret);
}

/**
 * gnutls_pubkey_set_pin_function:
 * @key: A key of type #gnutls_pubkey_t
 * @fn: the callback
 * @userdata: data associated with the callback
 *
 * This function will set a callback function to be used when
 * required to access the object. This function overrides any other
 * global PIN functions.
 *
 * Note that this function must be called right after initialization
 * to have effect.
 *
 * Since: 3.1.0
 *
 **/
void gnutls_pubkey_set_pin_function(gnutls_pubkey_t key,
				    gnutls_pin_callback_t fn,
				    void *userdata)
{
	key->pin.cb = fn;
	key->pin.data = userdata;
}

/**
 * gnutls_pubkey_import_x509_raw:
 * @pkey: The public key
 * @data: The public key data to be imported
 * @format: The format of the public key
 * @flags: should be zero
 *
 * This function will import the given public key to the abstract
 * #gnutls_pubkey_t structure. 
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 3.1.3
 **/
int gnutls_pubkey_import_x509_raw(gnutls_pubkey_t pkey,
				  const gnutls_datum_t * data,
				  gnutls_x509_crt_fmt_t format,
				  unsigned int flags)
{
	gnutls_x509_crt_t xpriv;
	int ret;

	ret = gnutls_x509_crt_init(&xpriv);
	if (ret < 0)
		return gnutls_assert_val(ret);

	ret = gnutls_x509_crt_import(xpriv, data, format);
	if (ret < 0) {
		gnutls_assert();
		goto cleanup;
	}

	ret = gnutls_pubkey_import_x509(pkey, xpriv, flags);
	if (ret < 0) {
		gnutls_assert();
		goto cleanup;
	}

	return 0;

      cleanup:
	gnutls_x509_crt_deinit(xpriv);

	return ret;
}

/**
 * gnutls_pubkey_verify_params:
 * @key: should contain a #gnutls_pubkey_t structure
 *
 * This function will verify the private key parameters.
 *
 * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
 *   negative error value.
 *
 * Since: 3.3.0
 **/
int gnutls_pubkey_verify_params(gnutls_pubkey_t key)
{
	int ret;

	ret = _gnutls_pk_verify_pub_params(key->pk_algorithm, &key->params);
	if (ret < 0) {
		gnutls_assert();
		return ret;
	}

	return 0;
}

/* ABI Compatibility functions */
#undef gnutls_pubkey_get_pk_ecc_x962
int gnutls_pubkey_get_pk_ecc_x962(gnutls_pubkey_t key,
				  gnutls_datum_t * parameters,
				  gnutls_datum_t * ecpoint);

int gnutls_pubkey_get_pk_ecc_x962(gnutls_pubkey_t key,
				  gnutls_datum_t * parameters,
				  gnutls_datum_t * ecpoint)
{
	return gnutls_pubkey_export_ecc_x962(key, parameters, ecpoint);
}

#undef gnutls_pubkey_get_pk_rsa_raw
int
gnutls_pubkey_get_pk_rsa_raw(gnutls_pubkey_t key,
			     gnutls_datum_t * m, gnutls_datum_t * e);

int
gnutls_pubkey_get_pk_rsa_raw(gnutls_pubkey_t key,
			     gnutls_datum_t * m, gnutls_datum_t * e)
{
	return gnutls_pubkey_export_rsa_raw(key, m, e);
}

#undef gnutls_pubkey_get_pk_dsa_raw
int
gnutls_pubkey_get_pk_dsa_raw(gnutls_pubkey_t key,
			     gnutls_datum_t * p, gnutls_datum_t * q,
			     gnutls_datum_t * g, gnutls_datum_t * y);

int
gnutls_pubkey_get_pk_dsa_raw(gnutls_pubkey_t key,
			     gnutls_datum_t * p, gnutls_datum_t * q,
			     gnutls_datum_t * g, gnutls_datum_t * y)
{
	return gnutls_pubkey_export_dsa_raw(key, p, q, g, y);
}


#undef gnutls_pubkey_get_pk_ecc_raw
int
gnutls_pubkey_get_pk_ecc_raw(gnutls_pubkey_t key,
			     gnutls_ecc_curve_t * curve,
			     gnutls_datum_t * x, gnutls_datum_t * y);

int
gnutls_pubkey_get_pk_ecc_raw(gnutls_pubkey_t key,
			     gnutls_ecc_curve_t * curve,
			     gnutls_datum_t * x, gnutls_datum_t * y)
{
	return gnutls_pubkey_export_ecc_raw(key, curve, x, y);
}