crypto/evp/p_open.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 "internal/cryptlib.h"
  11 #ifdef OPENSSL_NO_RSA
  12 NON_EMPTY_TRANSLATION_UNIT
  13 #else
  14
  15 # include <stdio.h>
  16 # include <openssl/evp.h>
  17 # include <openssl/objects.h>
  18 # include <openssl/x509.h>
  19 # include <openssl/rsa.h>
  20
  21 int EVP_OpenInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
  22                  const unsigned char *ek, int ekl, const unsigned char *iv,
  23                  EVP_PKEY *priv)
  24 {
  25     unsigned char *key = NULL;
  26     int i, size = 0, ret = 0;
  27
  28     if (type) {
  29         EVP_CIPHER_CTX_reset(ctx);
  30         if (!EVP_DecryptInit_ex(ctx, type, NULL, NULL, NULL))
  31             return 0;
  32     }
  33
  34     if (!priv)
  35         return 1;
  36
  37     if (EVP_PKEY_id(priv) != EVP_PKEY_RSA) {
  38         EVPerr(EVP_F_EVP_OPENINIT, EVP_R_PUBLIC_KEY_NOT_RSA);
  39         goto err;
  40     }
  41
  42     size = EVP_PKEY_size(priv);
  43     key = OPENSSL_malloc(size + 2);
  44     if (key == NULL) {
  45         /* ERROR */
  46         EVPerr(EVP_F_EVP_OPENINIT, ERR_R_MALLOC_FAILURE);
  47         goto err;
  48     }
  49
  50     i = EVP_PKEY_decrypt_old(key, ek, ekl, priv);
  51     if ((i <= 0) || !EVP_CIPHER_CTX_set_key_length(ctx, i)) {
  52         /* ERROR */
  53         goto err;
  54     }
  55     if (!EVP_DecryptInit_ex(ctx, NULL, NULL, key, iv))
  56         goto err;
  57
  58     ret = 1;
  59  err:
  60     OPENSSL_clear_free(key, size);
  61     return ret;
  62 }
  63
  64 int EVP_OpenFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
  65 {
  66     int i;
  67
  68     i = EVP_DecryptFinal_ex(ctx, out, outl);
  69     if (i)
  70         i = EVP_DecryptInit_ex(ctx, NULL, NULL, NULL, NULL);
  71     return i;
  72 }
  73 #endif