crypto/evp/p_sign.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 "crypto/evp.h"
  16
  17 int EVP_SignFinal(EVP_MD_CTX *ctx, unsigned char *sigret,
  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     size_t sltmp;
  24     EVP_PKEY_CTX *pkctx = NULL;
  25
  26     *siglen = 0;
  27     if (EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_FINALISE)) {
  28         if (!EVP_DigestFinal_ex(ctx, m, &m_len))
  29             goto err;
  30     } else {
  31         int rv = 0;
  32         EVP_MD_CTX *tmp_ctx = EVP_MD_CTX_new();
  33         if (tmp_ctx == NULL) {
  34             EVPerr(EVP_F_EVP_SIGNFINAL, ERR_R_MALLOC_FAILURE);
  35             return 0;
  36         }
  37         rv = EVP_MD_CTX_copy_ex(tmp_ctx, ctx);
  38         if (rv)
  39             rv = EVP_DigestFinal_ex(tmp_ctx, m, &m_len);
  40         EVP_MD_CTX_free(tmp_ctx);
  41         if (!rv)
  42             return 0;
  43     }
  44
  45     sltmp = (size_t)EVP_PKEY_size(pkey);
  46     i = 0;
  47     pkctx = EVP_PKEY_CTX_new(pkey, NULL);
  48     if (pkctx == NULL)
  49         goto err;
  50     if (EVP_PKEY_sign_init(pkctx) <= 0)
  51         goto err;
  52     if (EVP_PKEY_CTX_set_signature_md(pkctx, EVP_MD_CTX_md(ctx)) <= 0)
  53         goto err;
  54     if (EVP_PKEY_sign(pkctx, sigret, &sltmp, m, m_len) <= 0)
  55         goto err;
  56     *siglen = sltmp;
  57     i = 1;
  58  err:
  59     EVP_PKEY_CTX_free(pkctx);
  60     return i;
  61 }