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TIdHashMessageDigest4
Hierarchy, Methods, See Also, Unit: IdHashMessageDigest
Implements the MD4 message digest encryption algorithm.

    TIdHashMessageDigest4 = class(TIdHashMessageDigest)

Unit
IdHashMessageDigest
Description
TIdHashMessageDigest4 is a TIdHashMessageDigest descendant that implements the RSA-MD4 encryption algorithm as described in the Internet Standards document:

- RFC 1186 - MD4 Message Digest Algorithm (http://www.rfc-editor.org/rfc/rfc1186.txt)

TIdHashMessageDigest4 can be used in various cryptography implementations that require the RSA-MD4 algorithm. The RSA-MD4 algorithm takes an input message of an arbitrary length and produces a 128-bit "fingerprint" or "message digest" of the input.

The MD4 algorithm is used for digital signature applications, where a large file must be "compressed" in a secure manner before being signed with the RSA public-key cryptosystem.

The MD4 algorithm has been placed in the public domain.

TIdHashMessageDigest4.HashValue
TIdHashMessageDigest4, See Also
Implements calculation of the 128-bit "fingerprint" or "message digest" for the MD4 message digest algorithm.

    function HashValue(AStream: TStream): T4x4LongWordRecord; override;

Parameters
AStream: TStream
Stream containing input values for the message digest algorithm.
Return Value
T4x4LongWordRecord - 128-bit message digest calculated from the input data.
Description
HashValue is an overridden T4x4LongWordRecord function in TIdHashMessageDigest4 that implements calculation of the 128-bit "fingerprint" or "message digest" for the values in the AStream input stream. HashValue reads the byte values in AStream, and applies the message digest algorithm required for MD4.

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