/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL

 * project 2006.

 */

/* ====================================================================

 * Copyright (c) 2006,2007 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/err.h>

#include "../../evp/internal.h"

#include "../delocate.h"

#include "../digest/internal.h"

#include "../service_indicator/internal.h"

enum evp_sign_verify_t {

  evp_sign,

  evp_verify,

};

DEFINE_LOCAL_DATA(struct evp_md_pctx_ops, md_pctx_ops) {

  out->free = EVP_PKEY_CTX_free;

  out->dup = EVP_PKEY_CTX_dup;

}

static int uses_prehash(EVP_MD_CTX *ctx, enum evp_sign_verify_t op) {

  return (op == evp_sign) ? (ctx->pctx->pmeth->sign != NULL)

                          : (ctx->pctx->pmeth->verify != NULL);

}

static int do_sigver_init(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,

                          const EVP_MD *type, ENGINE *e, EVP_PKEY *pkey,

                          enum evp_sign_verify_t op) {

  if (ctx->pctx == NULL) {

    ctx->pctx = EVP_PKEY_CTX_new(pkey, e);

  }

  if (ctx->pctx == NULL) {

    return 0;

  }

  ctx->pctx_ops = md_pctx_ops();

  if (op == evp_verify) {

    if (!EVP_PKEY_verify_init(ctx->pctx)) {

      return 0;

    }

  } else {

    if (!EVP_PKEY_sign_init(ctx->pctx)) {

      return 0;

    }

  }

  if (type != NULL &&

      !EVP_PKEY_CTX_set_signature_md(ctx->pctx, type)) {

    return 0;

  }

  if (uses_prehash(ctx, op)) {

    if (type == NULL) {

      OPENSSL_PUT_ERROR(EVP, EVP_R_NO_DEFAULT_DIGEST);

      return 0;

    }

    if (!EVP_DigestInit_ex(ctx, type, e)) {

      return 0;

    }

  }

  if (pctx) {

    *pctx = ctx->pctx;

  }

  return 1;

}

int EVP_DigestSignInit(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx, const EVP_MD *type,

                       ENGINE *e, EVP_PKEY *pkey) {

  return do_sigver_init(ctx, pctx, type, e, pkey, evp_sign);

}

int EVP_DigestVerifyInit(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,

                         const EVP_MD *type, ENGINE *e, EVP_PKEY *pkey) {

  return do_sigver_init(ctx, pctx, type, e, pkey, evp_verify);

}

int EVP_DigestSignUpdate(EVP_MD_CTX *ctx, const void *data, size_t len) {

  if (!uses_prehash(ctx, evp_sign)) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

    return 0;

  }

  return EVP_DigestUpdate(ctx, data, len);

}

int EVP_DigestVerifyUpdate(EVP_MD_CTX *ctx, const void *data, size_t len) {

  if (!uses_prehash(ctx, evp_verify)) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

    return 0;

  }

  return EVP_DigestUpdate(ctx, data, len);

}

int EVP_DigestSignFinal(EVP_MD_CTX *ctx, uint8_t *out_sig,

                        size_t *out_sig_len) {

  if (!uses_prehash(ctx, evp_sign)) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

    return 0;

  }

  if (out_sig) {

    EVP_MD_CTX tmp_ctx;

    int ret;

    uint8_t md[EVP_MAX_MD_SIZE];

    unsigned int mdlen;

    FIPS_service_indicator_lock_state();

    EVP_MD_CTX_init(&tmp_ctx);

    ret = EVP_MD_CTX_copy_ex(&tmp_ctx, ctx) &&

          EVP_DigestFinal_ex(&tmp_ctx, md, &mdlen) &&

          EVP_PKEY_sign(ctx->pctx, out_sig, out_sig_len, md, mdlen);

    EVP_MD_CTX_cleanup(&tmp_ctx);

    FIPS_service_indicator_unlock_state();

    if (ret) {

      EVP_DigestSign_verify_service_indicator(ctx);

    }

    return ret;

  } else {

    size_t s = EVP_MD_size(ctx->digest);

    return EVP_PKEY_sign(ctx->pctx, out_sig, out_sig_len, NULL, s);

  }

}

int EVP_DigestVerifyFinal(EVP_MD_CTX *ctx, const uint8_t *sig,

                          size_t sig_len) {

  if (!uses_prehash(ctx, evp_verify)) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

    return 0;

  }

  EVP_MD_CTX tmp_ctx;

  int ret;

  uint8_t md[EVP_MAX_MD_SIZE];

  unsigned int mdlen;

  FIPS_service_indicator_lock_state();

  EVP_MD_CTX_init(&tmp_ctx);

  ret = EVP_MD_CTX_copy_ex(&tmp_ctx, ctx) &&

        EVP_DigestFinal_ex(&tmp_ctx, md, &mdlen) &&

        EVP_PKEY_verify(ctx->pctx, sig, sig_len, md, mdlen);

  FIPS_service_indicator_unlock_state();

  EVP_MD_CTX_cleanup(&tmp_ctx);

  if (ret) {

    EVP_DigestVerify_verify_service_indicator(ctx);

  }

  return ret;

}

int EVP_DigestSign(EVP_MD_CTX *ctx, uint8_t *out_sig, size_t *out_sig_len,

                   const uint8_t *data, size_t data_len) {

  FIPS_service_indicator_lock_state();

  int ret = 0;

  if (uses_prehash(ctx, evp_sign)) {

    // If |out_sig| is NULL, the caller is only querying the maximum output

    // length. |data| should only be incorporated in the final call.

    if (out_sig != NULL &&

        !EVP_DigestSignUpdate(ctx, data, data_len)) {

      goto end;

    }

    ret = EVP_DigestSignFinal(ctx, out_sig, out_sig_len);

    goto end;

  }

  if (ctx->pctx->pmeth->sign_message == NULL) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

    goto end;

  }

  ret = ctx->pctx->pmeth->sign_message(ctx->pctx, out_sig, out_sig_len, data,

                                       data_len);

end:

  FIPS_service_indicator_unlock_state();

  if (ret) {

    EVP_DigestSign_verify_service_indicator(ctx);

  }

  return ret;

}

int EVP_DigestVerify(EVP_MD_CTX *ctx, const uint8_t *sig, size_t sig_len,

                     const uint8_t *data, size_t len) {

  FIPS_service_indicator_lock_state();

  int ret = 0;

  if (uses_prehash(ctx, evp_verify)) {

    ret = EVP_DigestVerifyUpdate(ctx, data, len) &&

          EVP_DigestVerifyFinal(ctx, sig, sig_len);

    goto end;

  }

  if (ctx->pctx->pmeth->verify_message == NULL) {

    OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

    goto end;

  }

  ret = ctx->pctx->pmeth->verify_message(ctx->pctx, sig, sig_len, data, len);

end:

  FIPS_service_indicator_unlock_state();

  if (ret) {

    EVP_DigestVerify_verify_service_indicator(ctx);

  }

  return ret;

}