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Download A Secure File System Based on
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These two functions process the whole message and get the final message digest. SHA1_update function divides the character message into several 512-bit blocks and transforms them (using the previously presented function) one by one except the last block. SHA1_final function deals with the rest data of the message to be the last 512-bit block and transform it to get the final H-Array what is the message digest. Function: unsigned long * sha1(char * data, int data_len); This function is the interface provided to the outer systems. Users provide their character string of any length as the message and the function returns a 160-bit H-Array what holds the message digest. In this function, the macros and functions mentioned right above are called to process all the 512-bit blocks within the given message. 33
