1 files changed, 101 insertions, 0 deletions
diff --git a/CryptoPkg/Library/BaseCryptLib/Rand/CryptRandTsc.c b/CryptoPkg/Library/BaseCryptLib/Rand/CryptRandTsc.c
new file mode 100644
index 0000000000..bb8783d354
--- /dev/null
+++ b/CryptoPkg/Library/BaseCryptLib/Rand/CryptRandTsc.c
@@ -0,0 +1,101 @@
+/** @file
+  Pseudorandom Number Generator Wrapper Implementation over OpenSSL.
+
+Copyright (c) 2012, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "InternalCryptLib.h"
+#include <openssl/rand.h>
+#include <Library/PrintLib.h>
+
+/**
+  Sets up the seed value for the pseudorandom number generator.
+
+  This function sets up the seed value for the pseudorandom number generator.
+  If Seed is not NULL, then the seed passed in is used.
+  If Seed is NULL, then default seed is used.
+
+  @param[in]  Seed      Pointer to seed value.
+                        If NULL, default seed is used.
+  @param[in]  SeedSize  Size of seed value.
+                        If Seed is NULL, this parameter is ignored.
+
+  @retval TRUE   Pseudorandom number generator has enough entropy for random generation.
+  @retval FALSE  Pseudorandom number generator does not have enough entropy for random generation.
+
+**/
+BOOLEAN
+EFIAPI
+RandomSeed (
+  IN  CONST  UINT8  *Seed  OPTIONAL,
+  IN  UINTN         SeedSize
+  )
+{
+  CHAR8  DefaultSeed[128];
+
+  //
+  // Seed the pseudorandom number generator with user-supplied value.
+  // NOTE: A cryptographic PRNG must be seeded with unpredictable data.
+  //
+  if (Seed != NULL) {
+    RAND_seed (Seed, (UINT32) SeedSize);
+  } else {
+    //
+    // Retrieve current time.
+    //
+    AsciiSPrint (
+      DefaultSeed,
+      sizeof (DefaultSeed),
+      "UEFI Crypto Library default seed (%ld)",
+      AsmReadTsc ()
+      ); 
+
+    RAND_seed (DefaultSeed, sizeof (DefaultSeed));
+  }
+
+  return TRUE;
+}
+
+/**
+  Generates a pseudorandom byte stream of the specified size.
+
+  If Output is NULL, then return FALSE.
+
+  @param[out]  Output  Pointer to buffer to receive random value.
+  @param[in]   Size    Size of randome bytes to generate.
+
+  @retval TRUE   Pseudorandom byte stream generated successfully.
+  @retval FALSE  Pseudorandom number generator fails to generate due to lack of entropy.
+
+**/
+BOOLEAN
+EFIAPI
+RandomBytes (
+  OUT  UINT8  *Output,
+  IN   UINTN  Size
+  )
+{
+  //
+  // Check input parameters.
+  //
+  if (Output == NULL) {
+    return FALSE;
+  }
+
+  //
+  // Generate random data.
+  //
+  if (RAND_bytes (Output, (UINT32) Size) != 1) {
+    return FALSE;
+  }
+
+  return TRUE;
+}