sha1.h

#ifndef Sha1_h
#define Sha1_h

#include <inttypes.h>
#include "Print.h"

#define HASH_LENGTH     20
#define BLOCK_LENGTH    64

union _buffer {
    uint8_t b[BLOCK_LENGTH];
    uint32_t w[BLOCK_LENGTH / 4];
};

union _state {
    uint8_t b[HASH_LENGTH];
    uint32_t w[HASH_LENGTH/4];
};

class Sha1Class : public Print {

public:
    void init(void);
    void initHmac(const uint8_t* secret, int secretLength);
    uint8_t* result(void);
    uint8_t* resultHmac(void);
#if ARDUINO >= 100
    virtual size_t write(uint8_t);
#else
	virtual void write(uint8_t);
#endif
    using Print::write;
    
private:
    void pad();
    void addUncounted(uint8_t data);
    void hashBlock();
    uint32_t rol32(uint32_t number, uint8_t bits);
    _buffer buffer;
    uint8_t bufferOffset;
    _state state;
    uint32_t byteCount;
    uint8_t keyBuffer[BLOCK_LENGTH];
    uint8_t innerHash[HASH_LENGTH];
};

extern Sha1Class Sha1;

#endif