crypto/evp/p_verify.c

   1 /*
   2  * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include "internal/cryptlib.h"
  12 #include <openssl/evp.h>
  13 #include <openssl/objects.h>
  14 #include <openssl/x509.h>
  15 #include "internal/evp_int.h"
  16
  17 int EVP_VerifyFinal(EVP_MD_CTX *ctx, const unsigned char *sigbuf,
  18                     unsigned int siglen, EVP_PKEY *pkey)
  19 {
  20     unsigned char m[EVP_MAX_MD_SIZE];
  21     unsigned int m_len = 0;
  22     int i = 0;
  23     EVP_PKEY_CTX *pkctx = NULL;
  24
  25     if (EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_FINALISE)) {
  26         if (!EVP_DigestFinal_ex(ctx, m, &m_len))
  27             goto err;
  28     } else {
  29         int rv = 0;
  30         EVP_MD_CTX *tmp_ctx = EVP_MD_CTX_new();
  31         if (tmp_ctx == NULL) {
  32             EVPerr(EVP_F_EVP_VERIFYFINAL, ERR_R_MALLOC_FAILURE);
  33             return 0;
  34         }
  35         rv = EVP_MD_CTX_copy_ex(tmp_ctx, ctx);
  36         if (rv)
  37             rv = EVP_DigestFinal_ex(tmp_ctx, m, &m_len);
  38         EVP_MD_CTX_free(tmp_ctx);
  39         if (!rv)
  40             return 0;
  41     }
  42
  43     i = -1;
  44     pkctx = EVP_PKEY_CTX_new(pkey, NULL);
  45     if (pkctx == NULL)
  46         goto err;
  47     if (EVP_PKEY_verify_init(pkctx) <= 0)
  48         goto err;
  49     if (EVP_PKEY_CTX_set_signature_md(pkctx, EVP_MD_CTX_md(ctx)) <= 0)
  50         goto err;
  51     i = EVP_PKEY_verify(pkctx, sigbuf, siglen, m, m_len);
  52  err:
  53     EVP_PKEY_CTX_free(pkctx);
  54     return i;
  55 }