/* $OpenBSD: m_sigver.c,v 1.9 2021/05/09 14:25:40 tb 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_locl.h"

static int

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

    ENGINE *e, EVP_PKEY *pkey, int ver)

{

  if (ctx->pctx == NULL)

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

  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->verifyctx_init) {

      if (ctx->pctx->pmeth->verifyctx_init(ctx->pctx,

          ctx) <=0)

        return 0;

      ctx->pctx->operation = EVP_PKEY_OP_VERIFYCTX;

    } 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 (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, e))

    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, e, pkey, 0);

}

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, 1);

}

int

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

{

  EVP_PKEY_CTX *pctx = ctx->pctx;

  int sctx;

  int r = 0;

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

    EVP_PKEY_CTX *dctx;

    if (sigret == NULL)

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

    /* XXX - support EVP_MD_CTX_FLAG_FINALISE? */

    if ((dctx = EVP_PKEY_CTX_dup(ctx->pctx)) == NULL)

      return 0;

    r = dctx->pmeth->signctx(dctx, sigret, siglen, ctx);

    EVP_PKEY_CTX_free(dctx);

    return r;

  }

  if (ctx->pctx->pmeth->signctx)

    sctx = 1;

  else

    sctx = 0;

  if (sigret) {

    EVP_MD_CTX tmp_ctx;

    unsigned char md[EVP_MAX_MD_SIZE];

    unsigned int mdlen = 0;

    EVP_MD_CTX_init(&tmp_ctx);

    if (!EVP_MD_CTX_copy_ex(&tmp_ctx, ctx))

      return 0;

    if (sctx)

      r = tmp_ctx.pctx->pmeth->signctx(tmp_ctx.pctx,

          sigret, siglen, &tmp_ctx);

    else

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

    EVP_MD_CTX_cleanup(&tmp_ctx);

    if (sctx || !r)

      return r;

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

      return 0;

  } else {

    if (sctx) {

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

          siglen, ctx) <= 0)

        return 0;

    } else {

      int s = EVP_MD_size(ctx->digest);

      if (s < 0 || EVP_PKEY_sign(ctx->pctx, sigret, siglen,

          NULL, s) <= 0)

        return 0;

    }

  }

  return 1;

}

int

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

    const unsigned char *tbs, size_t tbslen)

{

  if (sigret != NULL) {

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

      return 0;

  }

  return EVP_DigestSignFinal(ctx, sigret, siglen);

}

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;

  int vctx;

  if (ctx->pctx->pmeth->verifyctx)

    vctx = 1;

  else

    vctx = 0;

  EVP_MD_CTX_init(&tmp_ctx);

  if (!EVP_MD_CTX_copy_ex(&tmp_ctx, ctx))

    return -1;

  if (vctx) {

    r = tmp_ctx.pctx->pmeth->verifyctx(tmp_ctx.pctx, sig,

        siglen, &tmp_ctx);

  } else

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

  EVP_MD_CTX_cleanup(&tmp_ctx);

  if (vctx || !r)

    return r;

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

}

int

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

    const unsigned char *tbs, size_t tbslen)

{

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

    return -1;

  return EVP_DigestVerifyFinal(ctx, sigret, siglen);

}