SLH-DSA Verify (FIPS 205)

Category: Post-Quantum Cryptography · Node Type ID: pqc-slhdsa-verify

Verifies stateless hash-based digital signature (FIPS 205)

Overview

Verifies a stateless hash-based SLH-DSA signature (NIST FIPS 205) against the message and the signer's public key, emitting a boolean verdict on the Valid output port.

Uses a Judgement Error Profile so invalid signatures emit Valid = false as normal data unless Treat As Error is configured.

When to Use

Verifying SLH-DSA signatures produced by SLH-DSA Sign.

Parameter Configuration

Parameter (ID)	Type & Default	Visibility Condition	Description & Options
Parameter Set `variant`	`select` Default: `slh_dsa_sha2_128s`	Always visible	Must match the FIPS 205 parameter set used during signing. `slh_dsa_sha2_128s`: SLH-DSA-SHA2-128s `slh_dsa_sha2_128f`: SLH-DSA-SHA2-128f `slh_dsa_shake_128s`: SLH-DSA-SHAKE-128s `slh_dsa_shake_128f`: SLH-DSA-SHAKE-128f `slh_dsa_sha2_256s`: SLH-DSA-SHA2-256s `slh_dsa_shake_256s`: SLH-DSA-SHAKE-256s
Treat As Error `errorOnValue`	`select` Default: `""` (empty)	Always visible	Judgement error reinterpretation: set to `false` (or `true`) to raise an error when `Valid` matches that value. `(empty)`: None (default; the result is plain data) `true`: true `false`: false
Error Code `errorCode`	`text` Default: `""` (empty) Supports Variable Reference (`$var`: `string`)	When `errorOnValue` is `true` or `false`	Custom error code when Treat As Error triggers.
Error Message `errorMessage`	`text` Default: `""` (empty) Supports Variable Reference (`$var`: `string`)	When `errorOnValue` is `true` or `false`	Custom error message when Treat As Error triggers.

Port I/O Specification

See Ports & Connections for general wiring rules, data type colors, and dynamic port creation.

Input Ports

Port Nature: Fixed Input Ports (3 total).

Port Name	Port ID	Data Type	Required	Visibility Condition	Description
`Public Key`	`publicKey`	`Bytes`	Required	Always visible	Signer's SLH-DSA public key (32B for 128-bit sets, 64B for 256-bit sets).
`Message Data`	`message`	`Bytes`	Required	Always visible	Original message bytes (`Uint8Array`).
`Signature`	`signature`	`Bytes`	Required	Always visible	Candidate SLH-DSA signature bytes to verify.

Output Ports

Port Nature: Fixed Output Ports (1 total).

Port Name	Port ID	Data Type	Visibility Condition	Description
`Valid`	`isValid`	`Bool`	Always visible	Boolean verification result (`true` if valid, `false` otherwise).

Error Cases

This node uses a Judgement Error Profile on its boolean output port isValid:

Default Behavior (Treat As Error = None): Verification or comparison mismatches do not raise a runtime error; instead, the node completes normally and emits false (or true) on isValid so downstream nodes or scripts can inspect the boolean result.
Reinterpretation as Error (Treat As Error = false or true): When the boolean verdict on isValid equals the configured errorOnValue setting, the engine transitions this node into an ERROR state using your custom Error Code and Error Message and halts downstream execution.

Examples

Verifying an SLH-DSA Signature

Verify an SLH-DSA signature against the 32-byte public key.

Connect Public Key, Message Data, and Signature to SLH-DSA Verify with matching Parameter Set.