Implement the SHA2 hash family

[libs/crypto.git] / source / sha2.h

diff --git a/source/sha2.h b/source/sha2.h
new file mode 100644 (file)
index 0000000..ed5c4fe
--- /dev/null
+++ b/source/sha2.h
@@ -0,0 +1,77 @@
+#ifndef MSP_CRYPTO_SHA2_H_
+#define MSP_CRYPTO_SHA2_H_
+
+#include <msp/core/inttypes.h>
+#include "blockhash.h"
+
+namespace Msp {
+namespace Crypto {
+
+template<typename C>
+class SHA2: public BlockHash<C::BLOCK_SIZE>
+{
+private:
+       typedef C Constants;
+       typedef typename Constants::WordType WordType;
+
+       typename Constants::WordType buffer[8];
+       UInt64 processed_bytes;
+
+public:
+       SHA2();
+       SHA2(const char *, unsigned);
+       SHA2(const std::string &);
+private:
+       void init();
+
+public:
+       virtual unsigned get_digest_size() const { return Constants::DIGEST_SIZE; }
+
+       virtual unsigned get_digest(char *, unsigned) const;
+
+private:
+       virtual void process_block(const char *);
+};
+
+
+struct SHA2_256Constants
+{
+       typedef UInt32 WordType;
+
+       enum
+       {
+               WORD_SIZE = sizeof(WordType),
+               BLOCK_SIZE = 64,   // 512 bits
+               DIGEST_SIZE = 32,  // 256 bits
+               N_ROUNDS = 64
+       };
+
+       static const WordType initial[8];
+       static const WordType round_constants[N_ROUNDS];
+       static const unsigned sigma_constants[12];
+};
+
+struct SHA2_512Constants
+{
+       typedef UInt64 WordType;
+
+       enum
+       {
+               WORD_SIZE = sizeof(WordType),
+               BLOCK_SIZE = 128,  // 1024 bits
+               DIGEST_SIZE = 64,  // 512 bits
+               N_ROUNDS = 80
+       };
+
+       static const WordType initial[8];
+       static const WordType round_constants[N_ROUNDS];
+       static const unsigned sigma_constants[12];
+};
+
+typedef SHA2<SHA2_256Constants> SHA256;
+typedef SHA2<SHA2_512Constants> SHA512;
+
+} // namespace Crypto
+} // namespace Msp
+
+#endif