Overview
SipHash is designed to make adversarial hash-collision attacks harder while staying efficient for small inputs.
ExtendedSource checked
SipHash
Computes a fast keyed hash for short messages and hash-table protection.
Quick Facts
Compact metadata for implementation and discovery.
- Category
- Cryptography
- Difficulty
- Intermediate
- Family
- Keyed Hashing
- Tier
- Extended
- Status
- Verified
- Review
- Source Checked
- Sources
- 1
- Formulas
- 0
- Relationships
- 3
- Code example
- Ready
- Visualization
- Ready
Core Concepts
keyed hashcompression roundshort messagecollision resistance
Quick facts
Complexity
Runtime and memory behavior at a glance.
Best
O(n)
Average
O(n)
Worst
O(n)
Space
O(1)
When to Use
- Use when protecting messages needs keyed hash.
- Use when the input matches the assumptions behind keyed Hashing.
When Not to Use
- Avoid when a well-reviewed library already provides the primitive for production use.
- Avoid when a simpler algorithm gives the required result with less setup.
What It Does
- Computes a fast keyed hash for short messages and hash-table protection
- Uses keyed hash and compression round to guide the work.
- Produces ciphertext, digest, proof, or derived key.
Use Cases
- Protecting messages
- Authenticating data
- Deriving or managing cryptographic material
Inputs
- Secret key or public parameters
- Message or secret data
- Nonce, salt, or context where needed
Outputs
- Ciphertext, digest, proof, or derived key
Pseudocode
- 1.Prepare the inputs and state needed for SipHash.
- 2.Apply the keyed hash step while the stopping condition has not been met.
- 3.Update intermediate state and discard invalid candidates.
- 4.Return ciphertext, digest, proof, or derived key.
Canonical Example
- Input
- SipHash input with a small representative case
- Output
- Ciphertext, digest, proof, or derived key
- Explanation
- SipHash applies keyed hash to produce ciphertext, digest, proof, or derived key.
Implementation Notes
- Use constant-time library implementations for real systems instead of hand-written primitives.
- Keep the keyed hash step separate enough to test independently.
Common Pitfalls
- Reusing nonces, salts, pads, or domain parameters can destroy the intended security property.
- Forgetting to check edge cases can make SipHash look correct on only ideal inputs.
Interactive Mechanism Walkthrough
Graph Frontier & Edge RelaxationShow the major cryptographic rounds or data dependencies without exposing secrets.
Step 1 of 4: Prepare the inputs and state needed for SipHash.
cryptography-mechanismNotes
SipHash is intended for keyed hashing of short inputs, not as a general-purpose cryptographic hash replacement.
Sources (1)
What each reference supports for this entry.
SipHash paper
PaperOriginal SipHash paper describing the keyed hash design for short inputs.
Open sourceExplore Next
Good next jumps from the relationship graph, ranked for useful discovery.
Relationships
View full relationship pageOften paired withHash Table
SipHash can protect hash tables against collision attacks.
Alternative toHMAC
SipHash is a keyed hash for hash-table protection rather than a general MAC construction.
Related Algorithms
Tags
CryptographyHash FunctionMessage AuthenticationSecurity