[Defect]: SipHash is misclassified as hash in cryptography registry

[Mehrn0ush]

Describe the defect

The cryptography registry currently classifies SipHash with primitive: "hash".

Expected behavior

SipHash should be classified as a keyed primitive rather than as an unkeyed hash. In the current registry taxonomy, mac appears to be the closest fit.

Actual behavior

SipHash is currently modeled as:

• family: SipHash
• pattern: SipHash[-{compressionRounds}-{finalizationRounds}]
• primitive: hash

SipHash is a keyed construction, not a general-purpose keyless hash like SHA-2 or SHA-3. It is commonly described and used as a short-input keyed function and is often used in MAC-like authentication contexts.

Proposed fix

• Change the SipHash variant primitive from hash to mac
• Update the current reference URL to a more canonical archival reference