unsigned hex_to_base64(const char* hex_buff, char* base64_buff, unsigned hex_buff_len );
int base64_to_hex(const unsigned char* const i_string, int i_string_len, unsigned char* o_hex_array );
void convert_string_to_hex(const char* const iArray, const unsigned iArrayLen, unsigned char* oHexArray);
void convert_hex_to_string(const unsigned char* const iHexArray, unsigned iHexArrayLen, char* oStringBuf );
void xor_strings(const char* const iLeftString, const char* const iRightString, unsigned char* oXorArray);
int c2b(char T);