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Version: 0.16 (unstable)

Cryptography

The Miden SDK exposes cryptographic primitives for signature verification and hashing. These are low-level functions used by authentication components and anywhere message digests or hash-based commitments are needed.

Falcon-512 Poseidon2 verification​

The core function for signature verification:

use miden::rpo_falcon512_verify;

// Verify a Falcon512 signature
// pk: Poseidon2 hash of the public key
// msg: Poseidon2 hash of the message
rpo_falcon512_verify(pk, msg);
ParameterTypeDescription
pkWordPoseidon2 hash of the signer's public key
msgWordPoseidon2 hash of the message being verified

The function panics (proof generation fails) if the signature is invalid.

The actual signature data is loaded onto the advice stack by the host. The Rust helper is still named rpo_falcon512_verify for compatibility, but the v0.15 verifier uses Falcon-512 over Poseidon2. You don't pass the signature as an argument.

Hashing​

hash_words creates a message digest from a slice of Words:

use miden::hash_words;

// Hash multiple Words into a Digest
let words = [commitment, nonce_word, extra_data];
let digest: Word = hash_words(&words).into();

Other available hash functions:

use miden::{blake3_hash, sha256_hash};

// BLAKE3 (32-byte input -> 32-byte output)
let hash: [u8; 32] = blake3_hash(input_bytes);

// SHA256 (32-byte input -> 32-byte output)
let hash: [u8; 32] = sha256_hash(input_bytes);