/* 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 <openssl/evp.h>

#include <openssl/bn.h>

#include <openssl/bytestring.h>

#include <openssl/digest.h>

#include <openssl/err.h>

#include <openssl/mem.h>

#include <openssl/rsa.h>

#include "../fipsmodule/rsa/internal.h"

#include "internal.h"

static int rsa_pub_encode(CBB *out, const EVP_PKEY *key) {

  // See RFC 3279, section 2.3.1.

  const RSA *rsa = key->pkey;

  CBB spki, algorithm, oid, null, key_bitstring;

  if (!CBB_add_asn1(out, &spki, CBS_ASN1_SEQUENCE) ||

      !CBB_add_asn1(&spki, &algorithm, CBS_ASN1_SEQUENCE) ||

      !CBB_add_asn1(&algorithm, &oid, CBS_ASN1_OBJECT) ||

      !CBB_add_bytes(&oid, rsa_asn1_meth.oid, rsa_asn1_meth.oid_len) ||

      !CBB_add_asn1(&algorithm, &null, CBS_ASN1_NULL) ||

      !CBB_add_asn1(&spki, &key_bitstring, CBS_ASN1_BITSTRING) ||

      !CBB_add_u8(&key_bitstring, 0 /* padding */) ||

      !RSA_marshal_public_key(&key_bitstring, rsa) ||

      !CBB_flush(out)) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_ENCODE_ERROR);

    return 0;

  }

  return 1;

}

static int rsa_pub_decode(EVP_PKEY *out, CBS *params, CBS *key) {

  // See RFC 3279, section 2.3.1.

  // The parameters must be NULL.

  CBS null;

  if (!CBS_get_asn1(params, &null, CBS_ASN1_NULL) ||

      CBS_len(&null) != 0 ||

      CBS_len(params) != 0) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_DECODE_ERROR);

    return 0;

  }

  RSA *rsa = RSA_parse_public_key(key);

  if (rsa == NULL || CBS_len(key) != 0) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_DECODE_ERROR);

    RSA_free(rsa);

    return 0;

  }

  EVP_PKEY_assign_RSA(out, rsa);

  return 1;

}

static int rsa_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b) {

  const RSA *a_rsa = a->pkey;

  const RSA *b_rsa = b->pkey;

  return BN_cmp(RSA_get0_n(b_rsa), RSA_get0_n(a_rsa)) == 0 &&

         BN_cmp(RSA_get0_e(b_rsa), RSA_get0_e(a_rsa)) == 0;

}

static int rsa_priv_encode(CBB *out, const EVP_PKEY *key) {

  const RSA *rsa = key->pkey;

  CBB pkcs8, algorithm, oid, null, private_key;

  if (!CBB_add_asn1(out, &pkcs8, CBS_ASN1_SEQUENCE) ||

      !CBB_add_asn1_uint64(&pkcs8, 0 /* version */) ||

      !CBB_add_asn1(&pkcs8, &algorithm, CBS_ASN1_SEQUENCE) ||

      !CBB_add_asn1(&algorithm, &oid, CBS_ASN1_OBJECT) ||

      !CBB_add_bytes(&oid, rsa_asn1_meth.oid, rsa_asn1_meth.oid_len) ||

      !CBB_add_asn1(&algorithm, &null, CBS_ASN1_NULL) ||

      !CBB_add_asn1(&pkcs8, &private_key, CBS_ASN1_OCTETSTRING) ||

      !RSA_marshal_private_key(&private_key, rsa) ||

      !CBB_flush(out)) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_ENCODE_ERROR);

    return 0;

  }

  return 1;

}

static int rsa_priv_decode(EVP_PKEY *out, CBS *params, CBS *key) {

  // Per RFC 3447, A.1, the parameters have type NULL.

  CBS null;

  if (!CBS_get_asn1(params, &null, CBS_ASN1_NULL) ||

      CBS_len(&null) != 0 ||

      CBS_len(params) != 0) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_DECODE_ERROR);

    return 0;

  }

  RSA *rsa = RSA_parse_private_key(key);

  if (rsa == NULL || CBS_len(key) != 0) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_DECODE_ERROR);

    RSA_free(rsa);

    return 0;

  }

  EVP_PKEY_assign_RSA(out, rsa);

  return 1;

}

static int rsa_opaque(const EVP_PKEY *pkey) {

  const RSA *rsa = pkey->pkey;

  return RSA_is_opaque(rsa);

}

static int int_rsa_size(const EVP_PKEY *pkey) {

  const RSA *rsa = pkey->pkey;

  return RSA_size(rsa);

}

static int rsa_bits(const EVP_PKEY *pkey) {

  const RSA *rsa = pkey->pkey;

  return RSA_bits(rsa);

}

static void int_rsa_free(EVP_PKEY *pkey) {

  RSA_free(pkey->pkey);

  pkey->pkey = NULL;

}

const EVP_PKEY_ASN1_METHOD rsa_asn1_meth = {

    EVP_PKEY_RSA,

    // 1.2.840.113549.1.1.1

    {0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x01},

    9,

    &rsa_pkey_meth,

    rsa_pub_decode,

    rsa_pub_encode,

    rsa_pub_cmp,

    rsa_priv_decode,

    rsa_priv_encode,

    /*set_priv_raw=*/NULL,

    /*set_pub_raw=*/NULL,

    /*get_priv_raw=*/NULL,

    /*get_pub_raw=*/NULL,

    /*set1_tls_encodedpoint=*/NULL,

    /*get1_tls_encodedpoint=*/NULL,

    rsa_opaque,

    int_rsa_size,

    rsa_bits,

    0,

    0,

    0,

    int_rsa_free,

};

int EVP_PKEY_set1_RSA(EVP_PKEY *pkey, RSA *key) {

  if (EVP_PKEY_assign_RSA(pkey, key)) {

    RSA_up_ref(key);

    return 1;

  }

  return 0;

}

int EVP_PKEY_assign_RSA(EVP_PKEY *pkey, RSA *key) {

  evp_pkey_set_method(pkey, &rsa_asn1_meth);

  pkey->pkey = key;

  return key != NULL;

}

RSA *EVP_PKEY_get0_RSA(const EVP_PKEY *pkey) {

  if (pkey->type != EVP_PKEY_RSA) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_EXPECTING_AN_RSA_KEY);

    return NULL;

  }

  return pkey->pkey;

}

RSA *EVP_PKEY_get1_RSA(const EVP_PKEY *pkey) {

  RSA *rsa = EVP_PKEY_get0_RSA(pkey);

  if (rsa != NULL) {

    RSA_up_ref(rsa);

  }

  return rsa;

}