/* $OpenBSD: m_sigver.c,v 1.27 2024/04/09 13:52:41 beck Exp $ */

/* 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 <stdio.h>

#include <openssl/err.h>

#include <openssl/evp.h>

#include <openssl/objects.h>

#include <openssl/x509.h>

#include "evp_local.h"

static int

update_oneshot_only(EVP_MD_CTX *ctx, const void *data, size_t datalen)

{

  EVPerror(EVP_R_ONLY_ONESHOT_SUPPORTED);

  return 0;

}

static int

do_sigver_init(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx, const EVP_MD *type,

    EVP_PKEY *pkey, int ver)

{

  if (ctx->pctx == NULL)

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

  if (ctx->pctx == NULL)

    return 0;

  if (!(ctx->pctx->pmeth->flags & EVP_PKEY_FLAG_SIGCTX_CUSTOM)) {

    if (type == NULL) {

      int def_nid;

      if (EVP_PKEY_get_default_digest_nid(pkey, &def_nid) > 0)

        type = EVP_get_digestbynid(def_nid);

    }

    if (type == NULL) {

      EVPerror(EVP_R_NO_DEFAULT_DIGEST);

      return 0;

    }

  }

  if (ver) {

    if (ctx->pctx->pmeth->digestverify != NULL) {

      ctx->pctx->operation = EVP_PKEY_OP_VERIFY;

      ctx->update = update_oneshot_only;

    } else if (EVP_PKEY_verify_init(ctx->pctx) <= 0)

      return 0;

  } else {

    if (ctx->pctx->pmeth->signctx_init) {

      if (ctx->pctx->pmeth->signctx_init(ctx->pctx, ctx) <= 0)

        return 0;

      ctx->pctx->operation = EVP_PKEY_OP_SIGNCTX;

    } else if (ctx->pctx->pmeth->digestsign != NULL) {

      ctx->pctx->operation = EVP_PKEY_OP_SIGN;

      ctx->update = update_oneshot_only;

    } else if (EVP_PKEY_sign_init(ctx->pctx) <= 0)

      return 0;

  }

  if (EVP_PKEY_CTX_set_signature_md(ctx->pctx, type) <= 0)

    return 0;

  if (pctx)

    *pctx = ctx->pctx;

  if (ctx->pctx->pmeth->flags & EVP_PKEY_FLAG_SIGCTX_CUSTOM)

    return 1;

  if (!EVP_DigestInit_ex(ctx, type, NULL))

    return 0;

  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, pkey, 0);

}

LCRYPTO_ALIAS(EVP_DigestSignInit);

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, pkey, 1);

}

LCRYPTO_ALIAS(EVP_DigestVerifyInit);

static int

evp_digestsignfinal_sigctx_custom(EVP_MD_CTX *ctx, unsigned char *sigret,

    size_t *siglen)

{

  EVP_PKEY_CTX *pctx = ctx->pctx;

  EVP_PKEY_CTX *dctx = NULL;

  int ret = 0;

  if (sigret == NULL)

    return pctx->pmeth->signctx(pctx, sigret, siglen, ctx);

  /* XXX - support EVP_MD_CTX_FLAG_FINALISE? */

  if ((dctx = EVP_PKEY_CTX_dup(pctx)) == NULL)

    goto err;

  if (!dctx->pmeth->signctx(dctx, sigret, siglen, ctx))

    goto err;

  ret = 1;

 err:

  EVP_PKEY_CTX_free(dctx);

  return ret;

}

int

EVP_DigestSignFinal(EVP_MD_CTX *ctx, unsigned char *sigret, size_t *siglen)

{

  EVP_PKEY_CTX *pctx = ctx->pctx;

  EVP_MD_CTX *md_ctx = NULL;

  unsigned char md[EVP_MAX_MD_SIZE];

  unsigned int mdlen = 0;

  int s;

  int ret = 0;

  if (pctx->pmeth->flags & EVP_PKEY_FLAG_SIGCTX_CUSTOM)

    return evp_digestsignfinal_sigctx_custom(ctx, sigret, siglen);

  if (sigret == NULL) {

    if (ctx->pctx->pmeth->signctx != NULL) {

      if (ctx->pctx->pmeth->signctx(ctx->pctx, NULL,

          siglen, ctx) <= 0)

        return 0;

      return 1;

    }

    if ((s = EVP_MD_size(ctx->digest)) < 0)

      return 0;

    if (EVP_PKEY_sign(ctx->pctx, NULL, siglen, NULL, s) <= 0)

      return 0;

    return 1;

  }

  /* Use a copy since EVP_DigestFinal_ex() clears secrets. */

  if ((md_ctx = EVP_MD_CTX_new()) == NULL)

    goto err;

  if (!EVP_MD_CTX_copy_ex(md_ctx, ctx))

    goto err;

  if (md_ctx->pctx->pmeth->signctx != NULL) {

    if (md_ctx->pctx->pmeth->signctx(md_ctx->pctx,

        sigret, siglen, md_ctx) <= 0)

      goto err;

  } else {

    if (!EVP_DigestFinal_ex(md_ctx, md, &mdlen))

      goto err;

    /* Use the original ctx since secrets were cleared. */

    if (EVP_PKEY_sign(ctx->pctx, sigret, siglen, md, mdlen) <= 0)

      goto err;

  }

  ret = 1;

 err:

  EVP_MD_CTX_free(md_ctx);

  return ret;

}

LCRYPTO_ALIAS(EVP_DigestSignFinal);

int

EVP_DigestSign(EVP_MD_CTX *ctx, unsigned char *sigret, size_t *siglen,

    const unsigned char *tbs, size_t tbslen)

{

  if (ctx->pctx->pmeth->digestsign != NULL)

    return ctx->pctx->pmeth->digestsign(ctx, sigret, siglen,

        tbs, tbslen);

  if (sigret != NULL) {

    if (EVP_DigestSignUpdate(ctx, tbs, tbslen) <= 0)

      return 0;

  }

  return EVP_DigestSignFinal(ctx, sigret, siglen);

}

LCRYPTO_ALIAS(EVP_DigestSign);

int

EVP_DigestVerifyFinal(EVP_MD_CTX *ctx, const unsigned char *sig, size_t siglen)

{

  EVP_MD_CTX tmp_ctx;

  unsigned char md[EVP_MAX_MD_SIZE];

  int r;

  unsigned int mdlen = 0;

  EVP_MD_CTX_legacy_clear(&tmp_ctx);

  if (!EVP_MD_CTX_copy_ex(&tmp_ctx, ctx))

    return -1;

  r = EVP_DigestFinal_ex(&tmp_ctx, md, &mdlen);

  EVP_MD_CTX_cleanup(&tmp_ctx);

  if (!r)

    return r;

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

}

LCRYPTO_ALIAS(EVP_DigestVerifyFinal);

int

EVP_DigestVerify(EVP_MD_CTX *ctx, const unsigned char *sigret, size_t siglen,

    const unsigned char *tbs, size_t tbslen)

{

  if (ctx->pctx->pmeth->digestverify != NULL)

    return ctx->pctx->pmeth->digestverify(ctx, sigret, siglen,

        tbs, tbslen);

  if (EVP_DigestVerifyUpdate(ctx, tbs, tbslen) <= 0)

    return -1;

  return EVP_DigestVerifyFinal(ctx, sigret, siglen);

}

LCRYPTO_ALIAS(EVP_DigestVerify);