digest-hmac: Digest-HMAC digest-hmac: digest-hmac: HMAC is used for message integrity checks between two parties that digest-hmac: share a secret key, and works in combination with some other digest-hmac: Digest algorithm, usually MD5 or SHA-1. digest-hmac: digest-hmac: digest-hmac: digest-hmac: digest-hmac: digest-hmac: