CryptoPkg/Library/BaseCryptLib/Hash/CryptSha256.c

   1 /** @file
   2   SHA-256 Digest Wrapper Implementation over OpenSSL.
   3
   4 Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>
   5 This program and the accompanying materials
   6 are licensed and made available under the terms and conditions of the BSD License
   7 which accompanies this distribution.  The full text of the license may be found at
   8 http://opensource.org/licenses/bsd-license.php
   9
  10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include <Library/BaseLib.h>
  16 #include <Library/DebugLib.h>
  17
  18 #include <Library/BaseCryptLib.h>
  19 #include <openssl/sha.h>
  20
  21
  22 /**
  23   Retrieves the size, in bytes, of the context buffer required for SHA-256 operations.
  24
  25   @return  The size, in bytes, of the context buffer required for SHA-256 operations.
  26
  27 **/
  28 UINTN
  29 EFIAPI
  30 Sha256GetContextSize (
  31   VOID
  32   )
  33 {
  34   //
  35   // Retrieves OpenSSL SHA-256 Context Size
  36   //
  37   return (UINTN)(sizeof (SHA256_CTX));
  38 }
  39
  40
  41 /**
  42   Initializes user-supplied memory pointed by Sha256Context as SHA-256 hash context for
  43   subsequent use.
  44
  45   If Sha256Context is NULL, then ASSERT().
  46
  47   @param[in, out]  Sha256Context  Pointer to SHA-256 Context being initialized.
  48
  49   @retval TRUE   SHA-256 context initialization succeeded.
  50   @retval FALSE  SHA-256 context initialization failed.
  51
  52 **/
  53 BOOLEAN
  54 EFIAPI
  55 Sha256Init (
  56   IN OUT  VOID  *Sha256Context
  57   )
  58 {
  59   //
  60   // ASSERT if Sha256Context is NULL
  61   //
  62   ASSERT (Sha256Context != NULL);
  63
  64   //
  65   // OpenSSL SHA-256 Context Initialization
  66   //
  67   return (BOOLEAN) (SHA256_Init ((SHA256_CTX *)Sha256Context));
  68 }
  69
  70
  71 /**
  72   Performs SHA-256 digest on a data buffer of the specified length. This function can
  73   be called multiple times to compute the digest of long or discontinuous data streams.
  74
  75   If Sha256Context is NULL, then ASSERT().
  76
  77   @param[in, out]  Sha256Context  Pointer to the SHA-256 context.
  78   @param[in]       Data           Pointer to the buffer containing the data to be hashed.
  79   @param[in]       DataLength     Length of Data buffer in bytes.
  80
  81   @retval TRUE   SHA-256 data digest succeeded.
  82   @retval FALSE  Invalid SHA-256 context. After Sha256Final function has been called, the
  83                  SHA-256 context cannot be reused.
  84
  85 **/
  86 BOOLEAN
  87 EFIAPI
  88 Sha256Update (
  89   IN OUT  VOID        *Sha256Context,
  90   IN      CONST VOID  *Data,
  91   IN      UINTN       DataLength
  92   )
  93 {
  94   //
  95   // ASSERT if Sha256Context is NULL
  96   //
  97   ASSERT (Sha256Context != NULL);
  98
  99   //
 100   // ASSERT if invalid parameters, in case that only DataLength was checked in OpenSSL
 101   //
 102   if (Data == NULL) {
 103     ASSERT (DataLength == 0);
 104   }
 105
 106   //
 107   // OpenSSL SHA-256 Hash Update
 108   //
 109   return (BOOLEAN) (SHA256_Update ((SHA256_CTX *)Sha256Context, Data, DataLength));
 110 }
 111
 112
 113 /**
 114   Completes SHA-256 hash computation and retrieves the digest value into the specified
 115   memory. After this function has been called, the SHA-256 context cannot be used again.
 116
 117   If Sha256Context is NULL, then ASSERT().
 118   If HashValue is NULL, then ASSERT().
 119
 120   @param[in, out]  Sha256Context  Pointer to SHA-256 context
 121   @param[out]      HashValue      Pointer to a buffer that receives the SHA-256 digest
 122                                   value (32 bytes).
 123
 124   @retval TRUE   SHA-256 digest computation succeeded.
 125   @retval FALSE  SHA-256 digest computation failed.
 126
 127 **/
 128 BOOLEAN
 129 EFIAPI
 130 Sha256Final (
 131   IN OUT  VOID   *Sha256Context,
 132   OUT     UINT8  *HashValue
 133   )
 134 {
 135   //
 136   // ASSERT if Sha256Context is NULL or HashValue is NULL
 137   //
 138   ASSERT (Sha256Context != NULL);
 139   ASSERT (HashValue     != NULL);
 140
 141   //
 142   // OpenSSL SHA-256 Hash Finalization
 143   //
 144   return (BOOLEAN) (SHA256_Final (HashValue, (SHA256_CTX *)Sha256Context));
 145 }