MESSAGE-DIGEST function

Hashes any of several types of source data using the specified hashing algorithm, and returns a RAW message digest value whose size and security depends on the algorithm.

Syntax 

 

MESSAGE-DIGEST( hash-algorithm, data-to-hash [ , hash-key ] )

hash-algorithm

A character string that specifies the hashing algorithm to hash the data specified by data-to-hash. You can specify one of the following options, in increasing order of security and decreasing order of performance:

"MD5" — RSA Message Digest Hash Algorithm, which returns a 16-byte RAW binary message digest value.

"SHA-1" — United States Government Secure Hash Algorithm, which returns a RAW 20-byte binary message digest value.

"SHA-256" — United States Government Secure Hash Algorithm, which returns a RAW 32-byte binary message digest value.

"SHA-512" — United States Government Secure Hash Algorithm, which returns a RAW 64-byte binary message digest value.

data-to-hash

The source data to hash. The data may be of type CHARACTER, LONGCHAR, RAW, or MEMPTR. If the data is a CHARACTER or LONGCHAR value, the AVM converts it to UTF-8 (which ensures a consistent value regardless of code page settings). To avoid this automatic conversion, specify a RAW or MEMPTR value.

hash-key

An optional key value to use in the hash operation. The key may be of type CHARACTER, LONGCHAR, RAW, or MEMPTR. If the key is a CHARACTER or LONGCHAR value, the AVM converts it to UTF-8 (which ensures a consistent value regardless of code page settings). To avoid this automatic conversion, specify a RAW or MEMPTR value. This key value is combined with the source data before the hash operation begins.

If the hash-key value contains a null character, the null character is included in the hash operation.

See also 

MD5-DIGEST function, SHA1-DIGEST function