SHA1Fingerprint()

Syntax

Result$ = SHA1Fingerprint(*Buffer, Size)

Returns a 40 characters long SHA1 (Secure Hash Algorithm 1) hash code of the given memory buffer.

Parameters

*Buffer	The buffer containing the data to be hashed.
Size	The size of the given buffer.

Return value

Returns the hash code as a string.

Remarks

SHA1 can be used to calculate a checksum to verify that a 'message' has not been altered. Unlike CRC32 it is nearly impossible to modify the original message and still produce the same SHA1 fingerprint.

Here is a quick explanation taken from the RFC 3174 on SHA1:

'The SHA-1 is called secure because it is computationally infeasible to find a message which corresponds to a given message digest, or to find two different messages which produce the same message digest. Any change to a message in transit will, with very high probability, result in a different message digest, and the signature will fail to verify.'

More information can be found in the RFC 3174: http://www.ietf.org/rfc/rfc3174.txt.

Example: a string as memory buffer

  test.s = "This is a test string!"
  Debug SHA1Fingerprint(@test, StringByteLength(test))

Example: with memory buffer

  *Buffer = AllocateMemory(500)    
  If *Buffer
    PokeS(*Buffer, "The quick brown fox jumps over the lazy dog.")
    SHA1$ = SHA1Fingerprint(*Buffer, MemorySize(*Buffer))
    Debug "SHA1 Fingerprint = " + SHA1$
    FreeMemory(*Buffer)  ; would also be done automatically at the end of the program
  EndIf

See Also

SHA1FileFingerprint(), ExamineSHA1Fingerprint(), MD5Fingerprint(), CRC32Fingerprint()

Supported OS

All