diff options
| author | Vadim Dashevskiy <watcherhd@gmail.com> | 2012-05-15 10:38:20 +0000 |
|---|---|---|
| committer | Vadim Dashevskiy <watcherhd@gmail.com> | 2012-05-15 10:38:20 +0000 |
| commit | 48540940b6c28bb4378abfeb500ec45a625b37b6 (patch) | |
| tree | 2ef294c0763e802f91d868bdef4229b6868527de /plugins/CryptoPP/crypto/crc.h | |
| parent | 5c350913f011e119127baeb32a6aedeb4f0d33bc (diff) | |
initial commit
git-svn-id: http://svn.miranda-ng.org/main/trunk@2 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c
Diffstat (limited to 'plugins/CryptoPP/crypto/crc.h')
| -rw-r--r-- | plugins/CryptoPP/crypto/crc.h | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/plugins/CryptoPP/crypto/crc.h b/plugins/CryptoPP/crypto/crc.h new file mode 100644 index 0000000000..ffe90f4c46 --- /dev/null +++ b/plugins/CryptoPP/crypto/crc.h @@ -0,0 +1,41 @@ +#ifndef CRYPTOPP_CRC32_H
+#define CRYPTOPP_CRC32_H
+
+#include "cryptlib.h"
+
+NAMESPACE_BEGIN(CryptoPP)
+
+const word32 CRC32_NEGL = 0xffffffffL;
+
+#ifdef IS_LITTLE_ENDIAN
+#define CRC32_INDEX(c) (c & 0xff)
+#define CRC32_SHIFTED(c) (c >> 8)
+#else
+#define CRC32_INDEX(c) (c >> 24)
+#define CRC32_SHIFTED(c) (c << 8)
+#endif
+
+//! CRC Checksum Calculation
+class CRC32 : public HashTransformation
+{
+public:
+ CRYPTOPP_CONSTANT(DIGESTSIZE = 4)
+ CRC32();
+ void Update(const byte *input, size_t length);
+ void TruncatedFinal(byte *hash, size_t size);
+ unsigned int DigestSize() const {return DIGESTSIZE;}
+ std::string AlgorithmName() const {return "CRC32";}
+
+ void UpdateByte(byte b) {m_crc = m_tab[CRC32_INDEX(m_crc) ^ b] ^ CRC32_SHIFTED(m_crc);}
+ byte GetCrcByte(size_t i) const {return ((byte *)&(m_crc))[i];}
+
+private:
+ void Reset() {m_crc = CRC32_NEGL;}
+
+ static const word32 m_tab[256];
+ word32 m_crc;
+};
+
+NAMESPACE_END
+
+#endif
|