15.06

CPP/7zip/Crypto/HmacSha256.cpp

@@ -0,0 +1,62 @@
+// HmacSha256.cpp
+
+#include "StdAfx.h"
+
+#include "../../../C/CpuArch.h"
+
+#include "HmacSha256.h"
+
+namespace NCrypto {
+namespace NSha256 {
+
+static const unsigned kBlockSize = 64;
+
+void CHmac::SetKey(const Byte *key, size_t keySize)
+{
+  Byte temp[kBlockSize];
+  size_t i;
+  
+  for (i = 0; i < kBlockSize; i++)
+    temp[i] = 0;
+  
+  if (keySize > kBlockSize)
+  {
+    Sha256_Init(&_sha);
+    Sha256_Update(&_sha, key, keySize);
+    Sha256_Final(&_sha, temp);
+  }
+  else
+    for (i = 0; i < keySize; i++)
+      temp[i] = key[i];
+  
+  for (i = 0; i < kBlockSize; i++)
+    temp[i] ^= 0x36;
+  
+  Sha256_Init(&_sha);
+  Sha256_Update(&_sha, temp, kBlockSize);
+  
+  for (i = 0; i < kBlockSize; i++)
+    temp[i] ^= 0x36 ^ 0x5C;
+
+  Sha256_Init(&_sha2);
+  Sha256_Update(&_sha2, temp, kBlockSize);
+}
+
+void CHmac::Final(Byte *mac)
+{
+  Sha256_Final(&_sha, mac);
+  Sha256_Update(&_sha2, mac, SHA256_DIGEST_SIZE);
+  Sha256_Final(&_sha2, mac);
+}
+
+/*
+void CHmac::Final(Byte *mac, size_t macSize)
+{
+  Byte digest[SHA256_DIGEST_SIZE];
+  Final(digest);
+  for (size_t i = 0; i < macSize; i++)
+    mac[i] = digest[i];
+}
+*/
+
+}}