@ -1,3 +1,5 @@ |
|||||
//! Digital signature schemes supported by default in the Miden VM.
|
//! Digital signature schemes supported by default in the Miden VM.
|
||||
|
|
||||
pub mod rpo_falcon512;
|
pub mod rpo_falcon512;
|
||||
|
|
||||
|
pub mod rpo_stark;
|
@ -0,0 +1,24 @@ |
|||||
|
mod signature;
|
||||
|
pub use signature::{PublicKey, SecretKey, Signature};
|
||||
|
|
||||
|
mod stark;
|
||||
|
pub use stark::{PublicInputs, RescueAir};
|
||||
|
|
||||
|
// TESTS
|
||||
|
// ================================================================================================
|
||||
|
|
||||
|
#[cfg(test)]
|
||||
|
mod tests {
|
||||
|
use super::SecretKey;
|
||||
|
use crate::Word;
|
||||
|
|
||||
|
#[test]
|
||||
|
fn test_signature() {
|
||||
|
let sk = SecretKey::new(Word::default());
|
||||
|
|
||||
|
let message = Word::default();
|
||||
|
let signature = sk.sign(message);
|
||||
|
let pk = sk.public_key();
|
||||
|
assert!(pk.verify(message, &signature))
|
||||
|
}
|
||||
|
}
|
@ -0,0 +1,173 @@ |
|||||
|
use rand::{distributions::Uniform, prelude::Distribution, Rng};
|
||||
|
use winter_air::{FieldExtension, ProofOptions};
|
||||
|
use winter_math::{fields::f64::BaseElement, FieldElement};
|
||||
|
use winter_prover::Proof;
|
||||
|
use winter_utils::{ByteReader, ByteWriter, Deserializable, DeserializationError, Serializable};
|
||||
|
|
||||
|
use crate::{
|
||||
|
dsa::rpo_stark::stark::RpoSignatureScheme,
|
||||
|
hash::{rpo::Rpo256, DIGEST_SIZE},
|
||||
|
StarkField, Word, ZERO,
|
||||
|
};
|
||||
|
|
||||
|
// CONSTANTS
|
||||
|
// ================================================================================================
|
||||
|
|
||||
|
/// Specifies the parameters of the STARK underlying the signature scheme. These parameters provide
|
||||
|
/// at least 102 bits of security under the conjectured security of the toy protocol in
|
||||
|
/// the ethSTARK paper [1].
|
||||
|
///
|
||||
|
/// [1]: https://eprint.iacr.org/2021/582
|
||||
|
pub const PROOF_OPTIONS: ProofOptions =
|
||||
|
ProofOptions::new(30, 8, 12, FieldExtension::Quadratic, 4, 7, true);
|
||||
|
|
||||
|
// PUBLIC KEY
|
||||
|
// ================================================================================================
|
||||
|
|
||||
|
/// A public key for verifying signatures.
|
||||
|
///
|
||||
|
/// The public key is a [Word] (i.e., 4 field elements) that is the hash of the secret key.
|
||||
|
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
|
||||
|
pub struct PublicKey(Word);
|
||||
|
|
||||
|
impl PublicKey {
|
||||
|
/// Returns the [Word] defining the public key.
|
||||
|
pub fn inner(&self) -> Word {
|
||||
|
self.0
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
impl PublicKey {
|
||||
|
/// Verifies the provided signature against provided message and this public key.
|
||||
|
pub fn verify(&self, message: Word, signature: &Signature) -> bool {
|
||||
|
signature.verify(message, *self)
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
impl Serializable for PublicKey {
|
||||
|
fn write_into<W: ByteWriter>(&self, target: &mut W) {
|
||||
|
self.0.write_into(target);
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
impl Deserializable for PublicKey {
|
||||
|
fn read_from<R: ByteReader>(source: &mut R) -> Result<Self, DeserializationError> {
|
||||
|
let pk = <Word>::read_from(source)?;
|
||||
|
Ok(Self(pk))
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
// SECRET KEY
|
||||
|
// ================================================================================================
|
||||
|
|
||||
|
/// A secret key for generating signatures.
|
||||
|
///
|
||||
|
/// The secret key is a [Word] (i.e., 4 field elements).
|
||||
|
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
|
||||
|
pub struct SecretKey(Word);
|
||||
|
|
||||
|
impl SecretKey {
|
||||
|
/// Generates a secret key from OS-provided randomness.
|
||||
|
pub fn new(word: Word) -> Self {
|
||||
|
Self(word)
|
||||
|
}
|
||||
|
|
||||
|
/// Generates a secret key from a [Word].
|
||||
|
#[cfg(feature = "std")]
|
||||
|
pub fn random() -> Self {
|
||||
|
use rand::{rngs::StdRng, SeedableRng};
|
||||
|
|
||||
|
let mut rng = StdRng::from_entropy();
|
||||
|
Self::with_rng(&mut rng)
|
||||
|
}
|
||||
|
|
||||
|
/// Generates a secret_key using the provided random number generator `Rng`.
|
||||
|
pub fn with_rng<R: Rng>(rng: &mut R) -> Self {
|
||||
|
let mut sk = [ZERO; 4];
|
||||
|
let uni_dist = Uniform::from(0..BaseElement::MODULUS);
|
||||
|
|
||||
|
for s in sk.iter_mut() {
|
||||
|
let sampled_integer = uni_dist.sample(rng);
|
||||
|
*s = BaseElement::new(sampled_integer);
|
||||
|
}
|
||||
|
|
||||
|
Self(sk)
|
||||
|
}
|
||||
|
|
||||
|
/// Computes the public key corresponding to this secret key.
|
||||
|
pub fn public_key(&self) -> PublicKey {
|
||||
|
let mut elements = [BaseElement::ZERO; 8];
|
||||
|
elements[..DIGEST_SIZE].copy_from_slice(&self.0);
|
||||
|
let pk = Rpo256::hash_elements(&elements);
|
||||
|
PublicKey(pk.into())
|
||||
|
}
|
||||
|
|
||||
|
/// Signs a message with this secret key.
|
||||
|
pub fn sign(&self, message: Word) -> Signature {
|
||||
|
let signature: RpoSignatureScheme<Rpo256> = RpoSignatureScheme::new(PROOF_OPTIONS);
|
||||
|
let proof = signature.sign(self.0, message);
|
||||
|
Signature { proof }
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
impl Serializable for SecretKey {
|
||||
|
fn write_into<W: ByteWriter>(&self, target: &mut W) {
|
||||
|
self.0.write_into(target);
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
impl Deserializable for SecretKey {
|
||||
|
fn read_from<R: ByteReader>(source: &mut R) -> Result<Self, DeserializationError> {
|
||||
|
let sk = <Word>::read_from(source)?;
|
||||
|
Ok(Self(sk))
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
// SIGNATURE
|
||||
|
// ================================================================================================
|
||||
|
|
||||
|
/// An RPO STARK-based signature over a message.
|
||||
|
///
|
||||
|
/// The signature is a STARK proof of knowledge of a pre-image given an image where the map is
|
||||
|
/// the RPO permutation, the pre-image is the secret key and the image is the public key.
|
||||
|
/// The current implementation follows the description in [1] but relies on the conjectured security
|
||||
|
/// of the toy protocol in the ethSTARK paper [2], which gives us using the parameter set
|
||||
|
/// given in `PROOF_OPTIONS` a signature with $102$ bits of average-case existential unforgeability
|
||||
|
/// security against $2^{113}$-query bound adversaries that can obtain up to $2^{64}$ signatures
|
||||
|
/// under the same public key.
|
||||
|
///
|
||||
|
/// [1]: https://eprint.iacr.org/2024/1553
|
||||
|
/// [2]: https://eprint.iacr.org/2021/582
|
||||
|
#[derive(Debug, Clone, PartialEq, Eq)]
|
||||
|
pub struct Signature {
|
||||
|
proof: Proof,
|
||||
|
}
|
||||
|
|
||||
|
impl Signature {
|
||||
|
/// Returns the STARK proof constituting the signature.
|
||||
|
pub fn inner(&self) -> Proof {
|
||||
|
self.proof.clone()
|
||||
|
}
|
||||
|
|
||||
|
/// Returns true if this signature is a valid signature for the specified message generated
|
||||
|
/// against the secret key matching the specified public key.
|
||||
|
pub fn verify(&self, message: Word, pk: PublicKey) -> bool {
|
||||
|
let signature: RpoSignatureScheme<Rpo256> = RpoSignatureScheme::new(PROOF_OPTIONS);
|
||||
|
|
||||
|
let res = signature.verify(pk.inner(), message, self.proof.clone());
|
||||
|
res.is_ok()
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
impl Serializable for Signature {
|
||||
|
fn write_into<W: ByteWriter>(&self, target: &mut W) {
|
||||
|
self.proof.write_into(target);
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
impl Deserializable for Signature {
|
||||
|
fn read_from<R: ByteReader>(source: &mut R) -> Result<Self, DeserializationError> {
|
||||
|
let proof = Proof::read_from(source)?;
|
||||
|
Ok(Self { proof })
|
||||
|
}
|
||||
|
}
|
@ -0,0 +1,198 @@ |
|||||
|
use alloc::vec::Vec;
|
||||
|
|
||||
|
use winter_math::{fields::f64::BaseElement, FieldElement, ToElements};
|
||||
|
use winter_prover::{
|
||||
|
Air, AirContext, Assertion, EvaluationFrame, ProofOptions, TraceInfo,
|
||||
|
TransitionConstraintDegree,
|
||||
|
};
|
||||
|
|
||||
|
use crate::{
|
||||
|
hash::{ARK1, ARK2, MDS, STATE_WIDTH},
|
||||
|
Word, ZERO,
|
||||
|
};
|
||||
|
|
||||
|
// CONSTANTS
|
||||
|
// ================================================================================================
|
||||
|
|
||||
|
pub const HASH_CYCLE_LEN: usize = 8;
|
||||
|
|
||||
|
// AIR
|
||||
|
// ================================================================================================
|
||||
|
|
||||
|
pub struct RescueAir {
|
||||
|
context: AirContext<BaseElement>,
|
||||
|
pub_key: Word,
|
||||
|
}
|
||||
|
|
||||
|
impl Air for RescueAir {
|
||||
|
type BaseField = BaseElement;
|
||||
|
type PublicInputs = PublicInputs;
|
||||
|
|
||||
|
type GkrProof = ();
|
||||
|
type GkrVerifier = ();
|
||||
|
|
||||
|
// CONSTRUCTOR
|
||||
|
// --------------------------------------------------------------------------------------------
|
||||
|
fn new(trace_info: TraceInfo, pub_inputs: PublicInputs, options: ProofOptions) -> Self {
|
||||
|
let degrees = vec![
|
||||
|
// Apply RPO rounds.
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
TransitionConstraintDegree::new(7),
|
||||
|
];
|
||||
|
assert_eq!(STATE_WIDTH, trace_info.width());
|
||||
|
let context = AirContext::new(trace_info, degrees, 12, options);
|
||||
|
let context = context.set_num_transition_exemptions(1);
|
||||
|
RescueAir { context, pub_key: pub_inputs.pub_key }
|
||||
|
}
|
||||
|
|
||||
|
fn context(&self) -> &AirContext<Self::BaseField> {
|
||||
|
&self.context
|
||||
|
}
|
||||
|
|
||||
|
fn evaluate_transition<E: FieldElement + From<Self::BaseField>>(
|
||||
|
&self,
|
||||
|
frame: &EvaluationFrame<E>,
|
||||
|
periodic_values: &[E],
|
||||
|
result: &mut [E],
|
||||
|
) {
|
||||
|
let current = frame.current();
|
||||
|
let next = frame.next();
|
||||
|
// expected state width is 12 field elements
|
||||
|
debug_assert_eq!(STATE_WIDTH, current.len());
|
||||
|
debug_assert_eq!(STATE_WIDTH, next.len());
|
||||
|
|
||||
|
enforce_rpo_round(frame, result, periodic_values);
|
||||
|
}
|
||||
|
|
||||
|
fn get_assertions(&self) -> Vec<Assertion<Self::BaseField>> {
|
||||
|
let initial_step = 0;
|
||||
|
let last_step = self.trace_length() - 1;
|
||||
|
vec![
|
||||
|
// Assert that the capacity as well as the second half of the rate portion of the state
|
||||
|
// are initialized to `ZERO`.The first half of the rate is unconstrained as it will
|
||||
|
// contain the secret key
|
||||
|
Assertion::single(0, initial_step, Self::BaseField::ZERO),
|
||||
|
Assertion::single(1, initial_step, Self::BaseField::ZERO),
|
||||
|
Assertion::single(2, initial_step, Self::BaseField::ZERO),
|
||||
|
Assertion::single(3, initial_step, Self::BaseField::ZERO),
|
||||
|
Assertion::single(8, initial_step, Self::BaseField::ZERO),
|
||||
|
Assertion::single(9, initial_step, Self::BaseField::ZERO),
|
||||
|
Assertion::single(10, initial_step, Self::BaseField::ZERO),
|
||||
|
Assertion::single(11, initial_step, Self::BaseField::ZERO),
|
||||
|
// Assert that the public key is the correct one
|
||||
|
Assertion::single(4, last_step, self.pub_key[0]),
|
||||
|
Assertion::single(5, last_step, self.pub_key[1]),
|
||||
|
Assertion::single(6, last_step, self.pub_key[2]),
|
||||
|
Assertion::single(7, last_step, self.pub_key[3]),
|
||||
|
]
|
||||
|
}
|
||||
|
|
||||
|
fn get_periodic_column_values(&self) -> Vec<Vec<Self::BaseField>> {
|
||||
|
get_round_constants()
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
pub struct PublicInputs {
|
||||
|
pub(crate) pub_key: Word,
|
||||
|
pub(crate) msg: Word,
|
||||
|
}
|
||||
|
|
||||
|
impl PublicInputs {
|
||||
|
pub fn new(pub_key: Word, msg: Word) -> Self {
|
||||
|
Self { pub_key, msg }
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
impl ToElements<BaseElement> for PublicInputs {
|
||||
|
fn to_elements(&self) -> Vec<BaseElement> {
|
||||
|
let mut res = self.pub_key.to_vec();
|
||||
|
res.extend_from_slice(self.msg.as_ref());
|
||||
|
res
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
// HELPER EVALUATORS
|
||||
|
// ------------------------------------------------------------------------------------------------
|
||||
|
|
||||
|
/// Enforces constraints for a single round of the Rescue Prime Optimized hash functions.
|
||||
|
pub fn enforce_rpo_round<E: FieldElement + From<BaseElement>>(
|
||||
|
frame: &EvaluationFrame<E>,
|
||||
|
result: &mut [E],
|
||||
|
ark: &[E],
|
||||
|
) {
|
||||
|
// compute the state that should result from applying the first 5 operations of the RPO round to
|
||||
|
// the current hash state.
|
||||
|
let mut step1 = [E::ZERO; STATE_WIDTH];
|
||||
|
step1.copy_from_slice(frame.current());
|
||||
|
|
||||
|
apply_mds(&mut step1);
|
||||
|
// add constants
|
||||
|
for i in 0..STATE_WIDTH {
|
||||
|
step1[i] += ark[i];
|
||||
|
}
|
||||
|
apply_sbox(&mut step1);
|
||||
|
apply_mds(&mut step1);
|
||||
|
// add constants
|
||||
|
for i in 0..STATE_WIDTH {
|
||||
|
step1[i] += ark[STATE_WIDTH + i];
|
||||
|
}
|
||||
|
|
||||
|
// compute the state that should result from applying the inverse of the last operation of the
|
||||
|
// RPO round to the next step of the computation.
|
||||
|
let mut step2 = [E::ZERO; STATE_WIDTH];
|
||||
|
step2.copy_from_slice(frame.next());
|
||||
|
apply_sbox(&mut step2);
|
||||
|
|
||||
|
// make sure that the results are equal.
|
||||
|
for i in 0..STATE_WIDTH {
|
||||
|
result[i] = step2[i] - step1[i]
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
#[inline(always)]
|
||||
|
fn apply_sbox<E: FieldElement + From<BaseElement>>(state: &mut [E; STATE_WIDTH]) {
|
||||
|
state.iter_mut().for_each(|v| {
|
||||
|
let t2 = v.square();
|
||||
|
let t4 = t2.square();
|
||||
|
*v *= t2 * t4;
|
||||
|
});
|
||||
|
}
|
||||
|
|
||||
|
#[inline(always)]
|
||||
|
fn apply_mds<E: FieldElement + From<BaseElement>>(state: &mut [E; STATE_WIDTH]) {
|
||||
|
let mut result = [E::ZERO; STATE_WIDTH];
|
||||
|
result.iter_mut().zip(MDS).for_each(|(r, mds_row)| {
|
||||
|
state.iter().zip(mds_row).for_each(|(&s, m)| {
|
||||
|
*r += E::from(m) * s;
|
||||
|
});
|
||||
|
});
|
||||
|
*state = result
|
||||
|
}
|
||||
|
|
||||
|
/// Returns RPO round constants arranged in column-major form.
|
||||
|
pub fn get_round_constants() -> Vec<Vec<BaseElement>> {
|
||||
|
let mut constants = Vec::new();
|
||||
|
for _ in 0..(STATE_WIDTH * 2) {
|
||||
|
constants.push(vec![ZERO; HASH_CYCLE_LEN]);
|
||||
|
}
|
||||
|
|
||||
|
#[allow(clippy::needless_range_loop)]
|
||||
|
for i in 0..HASH_CYCLE_LEN - 1 {
|
||||
|
for j in 0..STATE_WIDTH {
|
||||
|
constants[j][i] = ARK1[i][j];
|
||||
|
constants[j + STATE_WIDTH][i] = ARK2[i][j];
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
constants
|
||||
|
}
|
@ -0,0 +1,69 @@ |
|||||
|
use core::marker::PhantomData;
|
||||
|
|
||||
|
use prover::RpoSignatureProver;
|
||||
|
use rand::{distributions::Standard, prelude::Distribution, thread_rng, RngCore, SeedableRng};
|
||||
|
use rand_chacha::ChaCha20Rng;
|
||||
|
use winter_crypto::{ElementHasher, Hasher, SaltedMerkleTree};
|
||||
|
use winter_math::fields::f64::BaseElement;
|
||||
|
use winter_prover::{Proof, ProofOptions, Prover};
|
||||
|
use winter_verifier::{verify, AcceptableOptions, VerifierError};
|
||||
|
|
||||
|
use crate::{
|
||||
|
hash::{rpo::Rpo256, DIGEST_SIZE},
|
||||
|
rand::RpoRandomCoin,
|
||||
|
};
|
||||
|
|
||||
|
mod air;
|
||||
|
pub use air::{PublicInputs, RescueAir};
|
||||
|
mod prover;
|
||||
|
|
||||
|
/// Represents an abstract STARK-based signature scheme with knowledge of RPO pre-image as
|
||||
|
/// the hard relation.
|
||||
|
pub struct RpoSignatureScheme<H: ElementHasher> {
|
||||
|
options: ProofOptions,
|
||||
|
_h: PhantomData<H>,
|
||||
|
}
|
||||
|
|
||||
|
impl<H: ElementHasher<BaseField = BaseElement> + Sync> RpoSignatureScheme<H>
|
||||
|
where
|
||||
|
Standard: Distribution<<H as Hasher>::Digest>,
|
||||
|
{
|
||||
|
pub fn new(options: ProofOptions) -> Self {
|
||||
|
RpoSignatureScheme { options, _h: PhantomData }
|
||||
|
}
|
||||
|
|
||||
|
pub fn sign(&self, sk: [BaseElement; DIGEST_SIZE], msg: [BaseElement; DIGEST_SIZE]) -> Proof {
|
||||
|
// create a prover
|
||||
|
let prover = RpoSignatureProver::<H>::new(msg, self.options.clone());
|
||||
|
|
||||
|
// generate execution trace
|
||||
|
let trace = prover.build_trace(sk);
|
||||
|
|
||||
|
// generate the initial seed for the PRNG used for zero-knowledge
|
||||
|
let mut seed = <ChaCha20Rng as SeedableRng>::Seed::default();
|
||||
|
let mut rng = thread_rng();
|
||||
|
rng.fill_bytes(&mut seed);
|
||||
|
|
||||
|
// generate the proof
|
||||
|
prover.prove(trace, Some(seed)).expect("failed to generate the signature")
|
||||
|
}
|
||||
|
|
||||
|
pub fn verify(
|
||||
|
&self,
|
||||
|
pub_key: [BaseElement; DIGEST_SIZE],
|
||||
|
msg: [BaseElement; DIGEST_SIZE],
|
||||
|
proof: Proof,
|
||||
|
) -> Result<(), VerifierError> {
|
||||
|
// we make sure that the parameters used in generating the proof match the expected ones
|
||||
|
if *proof.options() != self.options {
|
||||
|
return Err(VerifierError::UnacceptableProofOptions);
|
||||
|
}
|
||||
|
let pub_inputs = PublicInputs { pub_key, msg };
|
||||
|
let acceptable_options = AcceptableOptions::OptionSet(vec![proof.options().clone()]);
|
||||
|
verify::<RescueAir, Rpo256, RpoRandomCoin, SaltedMerkleTree<Rpo256, ChaCha20Rng>>(
|
||||
|
proof,
|
||||
|
pub_inputs,
|
||||
|
&acceptable_options,
|
||||
|
)
|
||||
|
}
|
||||
|
}
|
@ -0,0 +1,148 @@ |
|||||
|
use core::marker::PhantomData;
|
||||
|
|
||||
|
use rand_chacha::ChaCha20Rng;
|
||||
|
use winter_air::{
|
||||
|
AuxRandElements, ConstraintCompositionCoefficients, PartitionOptions, ZkParameters,
|
||||
|
};
|
||||
|
use winter_crypto::{ElementHasher, SaltedMerkleTree};
|
||||
|
use winter_math::{fields::f64::BaseElement, FieldElement};
|
||||
|
use winter_prover::{
|
||||
|
matrix::ColMatrix, CompositionPoly, CompositionPolyTrace, DefaultConstraintCommitment,
|
||||
|
DefaultConstraintEvaluator, DefaultTraceLde, ProofOptions, Prover, StarkDomain, Trace,
|
||||
|
TraceInfo, TracePolyTable, TraceTable,
|
||||
|
};
|
||||
|
|
||||
|
use super::air::{PublicInputs, RescueAir, HASH_CYCLE_LEN};
|
||||
|
use crate::{
|
||||
|
hash::{rpo::Rpo256, STATE_WIDTH},
|
||||
|
rand::RpoRandomCoin,
|
||||
|
Word, ZERO,
|
||||
|
};
|
||||
|
|
||||
|
// PROVER
|
||||
|
// ================================================================================================
|
||||
|
|
||||
|
/// A prover for the RPO STARK-based signature scheme.
|
||||
|
///
|
||||
|
/// The signature is based on the the one-wayness of the RPO hash function but it is generic over
|
||||
|
/// the hash function used for instantiating the random oracle for the BCS transform.
|
||||
|
pub(crate) struct RpoSignatureProver<H: ElementHasher + Sync> {
|
||||
|
message: Word,
|
||||
|
options: ProofOptions,
|
||||
|
_hasher: PhantomData<H>,
|
||||
|
}
|
||||
|
|
||||
|
impl<H: ElementHasher + Sync> RpoSignatureProver<H> {
|
||||
|
pub(crate) fn new(message: Word, options: ProofOptions) -> Self {
|
||||
|
Self { message, options, _hasher: PhantomData }
|
||||
|
}
|
||||
|
|
||||
|
pub(crate) fn build_trace(&self, sk: Word) -> TraceTable<BaseElement> {
|
||||
|
let mut trace = TraceTable::new(STATE_WIDTH, HASH_CYCLE_LEN);
|
||||
|
|
||||
|
trace.fill(
|
||||
|
|state| {
|
||||
|
// initialize first half of the rate portion of the state with the secret key
|
||||
|
state[0] = ZERO;
|
||||
|
state[1] = ZERO;
|
||||
|
state[2] = ZERO;
|
||||
|
state[3] = ZERO;
|
||||
|
state[4] = sk[0];
|
||||
|
state[5] = sk[1];
|
||||
|
state[6] = sk[2];
|
||||
|
state[7] = sk[3];
|
||||
|
state[8] = ZERO;
|
||||
|
state[9] = ZERO;
|
||||
|
state[10] = ZERO;
|
||||
|
state[11] = ZERO;
|
||||
|
},
|
||||
|
|step, state| {
|
||||
|
Rpo256::apply_round(
|
||||
|
state.try_into().expect("should not fail given the size of the array"),
|
||||
|
step,
|
||||
|
);
|
||||
|
},
|
||||
|
);
|
||||
|
trace
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
impl<H: ElementHasher> Prover for RpoSignatureProver<H>
|
||||
|
where
|
||||
|
H: ElementHasher<BaseField = BaseElement> + Sync,
|
||||
|
{
|
||||
|
type BaseField = BaseElement;
|
||||
|
type Air = RescueAir;
|
||||
|
type Trace = TraceTable<BaseElement>;
|
||||
|
type HashFn = Rpo256;
|
||||
|
type VC = SaltedMerkleTree<Self::HashFn, Self::ZkPrng>;
|
||||
|
type RandomCoin = RpoRandomCoin;
|
||||
|
type TraceLde<E: FieldElement<BaseField = Self::BaseField>> =
|
||||
|
DefaultTraceLde<E, Self::HashFn, Self::VC>;
|
||||
|
type ConstraintCommitment<E: FieldElement<BaseField = Self::BaseField>> =
|
||||
|
DefaultConstraintCommitment<E, Self::HashFn, Self::ZkPrng, Self::VC>;
|
||||
|
type ConstraintEvaluator<'a, E: FieldElement<BaseField = Self::BaseField>> =
|
||||
|
DefaultConstraintEvaluator<'a, Self::Air, E>;
|
||||
|
type ZkPrng = ChaCha20Rng;
|
||||
|
|
||||
|
fn get_pub_inputs(&self, trace: &Self::Trace) -> PublicInputs {
|
||||
|
let last_step = trace.length() - 1;
|
||||
|
// Note that the message is not part of the execution trace but is part of the public
|
||||
|
// inputs. This is explained in the reference description of the DSA and intuitively
|
||||
|
// it is done in order to make sure that the message is part of the Fiat-Shamir
|
||||
|
// transcript and hence binds the proof/signature to the message
|
||||
|
PublicInputs {
|
||||
|
pub_key: [
|
||||
|
trace.get(4, last_step),
|
||||
|
trace.get(5, last_step),
|
||||
|
trace.get(6, last_step),
|
||||
|
trace.get(7, last_step),
|
||||
|
],
|
||||
|
msg: self.message,
|
||||
|
}
|
||||
|
}
|
||||
|
|
||||
|
fn options(&self) -> &ProofOptions {
|
||||
|
&self.options
|
||||
|
}
|
||||
|
|
||||
|
fn new_trace_lde<E: FieldElement<BaseField = Self::BaseField>>(
|
||||
|
&self,
|
||||
|
trace_info: &TraceInfo,
|
||||
|
main_trace: &ColMatrix<Self::BaseField>,
|
||||
|
domain: &StarkDomain<Self::BaseField>,
|
||||
|
partition_option: PartitionOptions,
|
||||
|
zk_parameters: Option<ZkParameters>,
|
||||
|
prng: &mut Option<Self::ZkPrng>,
|
||||
|
) -> (Self::TraceLde<E>, TracePolyTable<E>) {
|
||||
|
DefaultTraceLde::new(trace_info, main_trace, domain, partition_option, zk_parameters, prng)
|
||||
|
}
|
||||
|
|
||||
|
fn new_evaluator<'a, E: FieldElement<BaseField = Self::BaseField>>(
|
||||
|
&self,
|
||||
|
air: &'a Self::Air,
|
||||
|
aux_rand_elements: Option<AuxRandElements<E>>,
|
||||
|
composition_coefficients: ConstraintCompositionCoefficients<E>,
|
||||
|
) -> Self::ConstraintEvaluator<'a, E> {
|
||||
|
DefaultConstraintEvaluator::new(air, aux_rand_elements, composition_coefficients)
|
||||
|
}
|
||||
|
|
||||
|
fn build_constraint_commitment<E: FieldElement<BaseField = Self::BaseField>>(
|
||||
|
&self,
|
||||
|
composition_poly_trace: CompositionPolyTrace<E>,
|
||||
|
num_constraint_composition_columns: usize,
|
||||
|
domain: &StarkDomain<Self::BaseField>,
|
||||
|
partition_options: PartitionOptions,
|
||||
|
zk_parameters: Option<ZkParameters>,
|
||||
|
prng: &mut Option<Self::ZkPrng>,
|
||||
|
) -> (Self::ConstraintCommitment<E>, CompositionPoly<E>) {
|
||||
|
DefaultConstraintCommitment::new(
|
||||
|
composition_poly_trace,
|
||||
|
num_constraint_composition_columns,
|
||||
|
domain,
|
||||
|
partition_options,
|
||||
|
zk_parameters,
|
||||
|
prng,
|
||||
|
)
|
||||
|
}
|
||||
|
}
|