Editing Cryptographic hash function (section)

=== Signature generation and verification ===
{{ main | Digital signature }}

Almost all [[digital signature]] schemes require a cryptographic hash to be calculated over the message. This allows the signature calculation to be performed on the relatively small, statically sized hash digest. The message is considered authentic if the signature verification succeeds given the signature and recalculated hash digest over the message. So the message integrity property of the cryptographic hash is used to create secure and efficient digital signature schemes.