SecretStore: threshold ECDSA PoC (#7615)
* SecretStore: ECDSA PoC * SecretStore: fixed ECDSA serialization + cleanup * removed unused param * removed unused method * removed debug unwrap * 1/x -> inv(x) * SecretStore: merged fixes from ECDSA session branch * once again 1/* -> inv(*) * fixed grumbles
This commit is contained in:
Svyatoslav Nikolsky
Marek Kotewicz
parent
226215eff6
commit
37bfcb737b
@ -48,6 +48,11 @@ impl Secret {
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Secret { inner: h }
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}
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/// Creates zero key, which is invalid for crypto operations, but valid for math operation.
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pub fn zero() -> Self {
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Secret { inner: Default::default() }
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}
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/// Imports and validates the key.
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pub fn from_unsafe_slice(key: &[u8]) -> Result<Self, Error> {
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let secret = key::SecretKey::from_slice(&super::SECP256K1, key)?;
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@ -61,16 +66,32 @@ impl Secret {
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/// Inplace add one secret key to another (scalar + scalar)
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pub fn add(&mut self, other: &Secret) -> Result<(), Error> {
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match (self.is_zero(), other.is_zero()) {
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(true, true) | (false, true) => Ok(()),
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(true, false) => {
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*self = other.clone();
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Ok(())
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},
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(false, false) => {
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let mut key_secret = self.to_secp256k1_secret()?;
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let other_secret = other.to_secp256k1_secret()?;
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key_secret.add_assign(&SECP256K1, &other_secret)?;
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*self = key_secret.into();
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Ok(())
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},
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}
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}
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/// Inplace subtract one secret key from another (scalar - scalar)
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pub fn sub(&mut self, other: &Secret) -> Result<(), Error> {
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match (self.is_zero(), other.is_zero()) {
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(true, true) | (false, true) => Ok(()),
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(true, false) => {
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*self = other.clone();
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self.neg()
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},
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(false, false) => {
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let mut key_secret = self.to_secp256k1_secret()?;
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let mut other_secret = other.to_secp256k1_secret()?;
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other_secret.mul_assign(&SECP256K1, &key::MINUS_ONE_KEY)?;
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@ -78,34 +99,58 @@ impl Secret {
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*self = key_secret.into();
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Ok(())
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},
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}
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}
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/// Inplace decrease secret key (scalar - 1)
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pub fn dec(&mut self) -> Result<(), Error> {
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match self.is_zero() {
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true => {
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*self = key::MINUS_ONE_KEY.into();
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Ok(())
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},
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false => {
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let mut key_secret = self.to_secp256k1_secret()?;
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key_secret.add_assign(&SECP256K1, &key::MINUS_ONE_KEY)?;
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*self = key_secret.into();
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Ok(())
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},
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}
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}
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/// Inplace multiply one secret key to another (scalar * scalar)
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pub fn mul(&mut self, other: &Secret) -> Result<(), Error> {
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match (self.is_zero(), other.is_zero()) {
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(true, true) | (true, false) => Ok(()),
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(false, true) => {
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*self = Self::zero();
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Ok(())
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},
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(false, false) => {
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let mut key_secret = self.to_secp256k1_secret()?;
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let other_secret = other.to_secp256k1_secret()?;
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key_secret.mul_assign(&SECP256K1, &other_secret)?;
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*self = key_secret.into();
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Ok(())
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},
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}
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}
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/// Inplace negate secret key (-scalar)
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pub fn neg(&mut self) -> Result<(), Error> {
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match self.is_zero() {
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true => Ok(()),
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false => {
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let mut key_secret = self.to_secp256k1_secret()?;
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key_secret.mul_assign(&SECP256K1, &key::MINUS_ONE_KEY)?;
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*self = key_secret.into();
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Ok(())
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},
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}
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}
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/// Inplace inverse secret key (1 / scalar)
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@ -120,6 +165,10 @@ impl Secret {
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/// Compute power of secret key inplace (secret ^ pow).
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/// This function is not intended to be used with large powers.
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pub fn pow(&mut self, pow: usize) -> Result<(), Error> {
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if self.is_zero() {
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return Ok(());
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}
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match pow {
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0 => *self = key::ONE_KEY.into(),
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1 => (),
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@ -18,6 +18,7 @@ use ethkey::{Public, Secret, Random, Generator, math};
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use ethereum_types::{H256, U256};
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use hash::keccak;
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use key_server_cluster::Error;
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#[cfg(test)] use ethkey::Signature;
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/// Encryption result.
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#[derive(Debug)]
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@ -28,16 +29,43 @@ pub struct EncryptedSecret {
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pub encrypted_point: Public,
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}
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/// Generate random scalar
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/// Create zero scalar.
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#[cfg(test)]
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pub fn zero_scalar() -> Secret {
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Secret::zero()
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}
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/// Convert hash to EC scalar (modulo curve order).
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pub fn to_scalar(hash: H256) -> Result<Secret, Error> {
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let scalar: U256 = hash.into();
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let scalar: H256 = (scalar % math::curve_order()).into();
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let scalar = Secret::from_slice(&*scalar);
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scalar.check_validity()?;
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Ok(scalar)
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}
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/// Generate random scalar.
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pub fn generate_random_scalar() -> Result<Secret, Error> {
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Ok(Random.generate()?.secret().clone())
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}
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/// Generate random point
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/// Generate random point.
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pub fn generate_random_point() -> Result<Public, Error> {
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Ok(Random.generate()?.public().clone())
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}
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/// Get X coordinate of point.
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#[cfg(test)]
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fn public_x(public: &Public) -> H256 {
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public[0..32].into()
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}
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/// Get Y coordinate of point.
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#[cfg(test)]
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fn public_y(public: &Public) -> H256 {
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public[32..64].into()
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}
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/// Compute publics sum.
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pub fn compute_public_sum<'a, I>(mut publics: I) -> Result<Public, Error> where I: Iterator<Item=&'a Public> {
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let mut sum = publics.next().expect("compute_public_sum is called when there's at least one public; qed").clone();
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@ -342,15 +370,10 @@ pub fn combine_message_hash_with_public(message_hash: &H256, public: &Public) ->
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let hash = keccak(&buffer[..]);
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// map hash to EC finite field value
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let hash: U256 = hash.into();
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let hash: H256 = (hash % math::curve_order()).into();
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let hash = Secret::from_slice(&*hash);
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hash.check_validity()?;
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Ok(hash)
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to_scalar(hash)
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}
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/// Compute signature share.
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/// Compute Schnorr signature share.
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pub fn compute_signature_share<'a, I>(threshold: usize, combined_hash: &Secret, one_time_secret_coeff: &Secret, node_secret_share: &Secret, node_number: &Secret, other_nodes_numbers: I)
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-> Result<Secret, Error> where I: Iterator<Item=&'a Secret> {
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let mut sum = one_time_secret_coeff.clone();
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@ -364,7 +387,7 @@ pub fn compute_signature_share<'a, I>(threshold: usize, combined_hash: &Secret,
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Ok(sum)
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}
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/// Check signature share.
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/// Check Schnorr signature share.
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pub fn _check_signature_share<'a, I>(_combined_hash: &Secret, _signature_share: &Secret, _public_share: &Public, _one_time_public_share: &Public, _node_numbers: I)
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-> Result<bool, Error> where I: Iterator<Item=&'a Secret> {
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// TODO [Trust]: in paper partial signature is checked using comparison:
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@ -384,7 +407,7 @@ pub fn _check_signature_share<'a, I>(_combined_hash: &Secret, _signature_share:
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Ok(true)
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}
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/// Compute signature.
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/// Compute Schnorr signature.
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pub fn compute_signature<'a, I>(signature_shares: I) -> Result<Secret, Error> where I: Iterator<Item=&'a Secret> {
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compute_secret_sum(signature_shares)
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}
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@ -405,7 +428,7 @@ pub fn local_compute_signature(nonce: &Secret, secret: &Secret, message_hash: &S
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Ok((combined_hash, sig))
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}
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/// Verify signature as described in https://en.wikipedia.org/wiki/Schnorr_signature#Verifying.
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/// Verify Schnorr signature as described in https://en.wikipedia.org/wiki/Schnorr_signature#Verifying.
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#[cfg(test)]
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pub fn verify_signature(public: &Public, signature: &(Secret, Secret), message_hash: &H256) -> Result<bool, Error> {
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let mut addendum = math::generation_point();
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@ -418,10 +441,104 @@ pub fn verify_signature(public: &Public, signature: &(Secret, Secret), message_h
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Ok(combined_hash == signature.0)
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}
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/// Compute R part of ECDSA signature.
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#[cfg(test)]
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pub fn compute_ecdsa_r(nonce_public: &Public) -> Result<Secret, Error> {
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to_scalar(public_x(nonce_public))
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}
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/// Compute share of S part of ECDSA signature.
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#[cfg(test)]
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pub fn compute_ecdsa_s_share(inv_nonce_share: &Secret, inv_nonce_mul_secret: &Secret, signature_r: &Secret, message_hash: &Secret) -> Result<Secret, Error> {
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let mut nonce_inv_share_mul_message_hash = inv_nonce_share.clone();
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nonce_inv_share_mul_message_hash.mul(&message_hash.clone().into())?;
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let mut nonce_inv_share_mul_secret_share_mul_r = inv_nonce_mul_secret.clone();
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nonce_inv_share_mul_secret_share_mul_r.mul(signature_r)?;
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let mut signature_s_share = nonce_inv_share_mul_message_hash;
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signature_s_share.add(&nonce_inv_share_mul_secret_share_mul_r)?;
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Ok(signature_s_share)
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}
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/// Compute S part of ECDSA signature from shares.
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#[cfg(test)]
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pub fn compute_ecdsa_s(t: usize, signature_s_shares: &[Secret], id_numbers: &[Secret]) -> Result<Secret, Error> {
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let double_t = t * 2;
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debug_assert!(id_numbers.len() >= double_t + 1);
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debug_assert_eq!(signature_s_shares.len(), id_numbers.len());
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compute_joint_secret_from_shares(double_t,
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&signature_s_shares.iter().take(double_t + 1).collect::<Vec<_>>(),
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&id_numbers.iter().take(double_t + 1).collect::<Vec<_>>())
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}
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/// Serialize ECDSA signature to [r][s]v form.
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#[cfg(test)]
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pub fn serialize_ecdsa_signature(nonce_public: &Public, signature_r: Secret, mut signature_s: Secret) -> Signature {
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// compute recvery param
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let mut signature_v = {
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let nonce_public_x = public_x(nonce_public);
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let nonce_public_y: U256 = public_y(nonce_public).into();
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let nonce_public_y_is_odd = !(nonce_public_y % 2.into()).is_zero();
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let bit0 = if nonce_public_y_is_odd { 1u8 } else { 0u8 };
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let bit1 = if nonce_public_x != *signature_r { 2u8 } else { 0u8 };
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bit0 | bit1
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};
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// fix high S
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let curve_order = math::curve_order();
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let curve_order_half = curve_order / 2.into();
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let s_numeric: U256 = (*signature_s).into();
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if s_numeric > curve_order_half {
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let signature_s_hash: H256 = (curve_order - s_numeric).into();
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signature_s = signature_s_hash.into();
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signature_v ^= 1;
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}
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// serialize as [r][s]v
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let mut signature = [0u8; 65];
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signature[..32].copy_from_slice(&**signature_r);
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signature[32..64].copy_from_slice(&**signature_s);
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signature[64] = signature_v;
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signature.into()
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}
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/// Compute share of ECDSA reversed-nonce coefficient. Result of this_coeff * secret_share gives us a share of inv(nonce).
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#[cfg(test)]
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pub fn compute_ecdsa_inversed_secret_coeff_share(secret_share: &Secret, nonce_share: &Secret, zero_share: &Secret) -> Result<Secret, Error> {
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let mut coeff = secret_share.clone();
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coeff.mul(nonce_share).unwrap();
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coeff.add(zero_share).unwrap();
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Ok(coeff)
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}
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/// Compute ECDSA reversed-nonce coefficient from its shares. Result of this_coeff * secret_share gives us a share of inv(nonce).
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#[cfg(test)]
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pub fn compute_ecdsa_inversed_secret_coeff_from_shares(t: usize, id_numbers: &[Secret], shares: &[Secret]) -> Result<Secret, Error> {
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debug_assert_eq!(shares.len(), 2 * t + 1);
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debug_assert_eq!(shares.len(), id_numbers.len());
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let u_shares = (0..2*t+1).map(|i| compute_shadow_mul(&shares[i], &id_numbers[i], id_numbers.iter().enumerate()
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.filter(|&(j, _)| i != j)
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.map(|(_, id)| id)
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.take(2 * t))).collect::<Result<Vec<_>, _>>()?;
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// compute u
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let u = compute_secret_sum(u_shares.iter())?;
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// compute inv(u)
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let mut u_inv = u;
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u_inv.inv()?;
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Ok(u_inv)
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}
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#[cfg(test)]
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pub mod tests {
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use std::iter::once;
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use ethkey::KeyPair;
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use ethkey::{KeyPair, recover, verify_public};
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use super::*;
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#[derive(Clone)]
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@ -434,7 +551,27 @@ pub mod tests {
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joint_public: Public,
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}
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fn run_key_generation(t: usize, n: usize, id_numbers: Option<Vec<Secret>>) -> KeyGenerationArtifacts {
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struct ZeroGenerationArtifacts {
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polynoms1: Vec<Vec<Secret>>,
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secret_shares: Vec<Secret>,
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}
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fn prepare_polynoms1(t: usize, n: usize, secret_required: Option<Secret>) -> Vec<Vec<Secret>> {
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let mut polynoms1: Vec<_> = (0..n).map(|_| generate_random_polynom(t).unwrap()).collect();
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// if we need specific secret to be shared, update polynoms so that sum of their free terms = required secret
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if let Some(mut secret_required) = secret_required {
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for polynom1 in polynoms1.iter_mut().take(n - 1) {
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let secret_coeff1 = generate_random_scalar().unwrap();
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secret_required.sub(&secret_coeff1).unwrap();
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polynom1[0] = secret_coeff1;
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}
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polynoms1[n - 1][0] = secret_required;
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}
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polynoms1
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}
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fn run_key_generation(t: usize, n: usize, id_numbers: Option<Vec<Secret>>, secret_required: Option<Secret>) -> KeyGenerationArtifacts {
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// === PART1: DKG ===
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// data, gathered during initialization
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@ -445,8 +582,9 @@ pub mod tests {
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};
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// data, generated during keys dissemination
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let polynoms1: Vec<_> = (0..n).map(|_| generate_random_polynom(t).unwrap()).collect();
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let polynoms1 = prepare_polynoms1(t, n, secret_required);
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let secrets1: Vec<_> = (0..n).map(|i| (0..n).map(|j| compute_polynom(&polynoms1[i], &id_numbers[j]).unwrap()).collect::<Vec<_>>()).collect();
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// following data is used only on verification step
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let polynoms2: Vec<_> = (0..n).map(|_| generate_random_polynom(t).unwrap()).collect();
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let secrets2: Vec<_> = (0..n).map(|i| (0..n).map(|j| compute_polynom(&polynoms2[i], &id_numbers[j]).unwrap()).collect::<Vec<_>>()).collect();
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@ -474,6 +612,20 @@ pub mod tests {
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}
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}
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fn run_zero_key_generation(t: usize, n: usize, id_numbers: &[Secret]) -> ZeroGenerationArtifacts {
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// data, generated during keys dissemination
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let polynoms1 = prepare_polynoms1(t, n, Some(zero_scalar()));
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let secrets1: Vec<_> = (0..n).map(|i| (0..n).map(|j| compute_polynom(&polynoms1[i], &id_numbers[j]).unwrap()).collect::<Vec<_>>()).collect();
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// data, generated during keys generation
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let secret_shares: Vec<_> = (0..n).map(|i| compute_secret_share(secrets1.iter().map(|s| &s[i])).unwrap()).collect();
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ZeroGenerationArtifacts {
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polynoms1: polynoms1,
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secret_shares: secret_shares,
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}
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}
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fn run_key_share_refreshing(old_t: usize, new_t: usize, new_n: usize, old_artifacts: &KeyGenerationArtifacts) -> KeyGenerationArtifacts {
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// === share refreshing protocol from
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// === based on "Verifiable Secret Redistribution for Threshold Sharing Schemes"
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@ -528,6 +680,56 @@ pub mod tests {
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result
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}
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fn run_multiplication_protocol(t: usize, secret_shares1: &[Secret], secret_shares2: &[Secret]) -> Vec<Secret> {
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let n = secret_shares1.len();
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assert!(t * 2 + 1 <= n);
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// shares of secrets multiplication = multiplication of secrets shares
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let mul_shares: Vec<_> = (0..n).map(|i| {
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let share1 = secret_shares1[i].clone();
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let share2 = secret_shares2[i].clone();
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let mut mul_share = share1;
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mul_share.mul(&share2).unwrap();
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mul_share
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}).collect();
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mul_shares
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}
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fn run_reciprocal_protocol(t: usize, artifacts: &KeyGenerationArtifacts) -> Vec<Secret> {
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// === Given a secret x mod r which is shared among n players, it is
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// === required to generate shares of inv(x) mod r with out revealing
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// === any information about x or inv(x).
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// === https://www.researchgate.net/publication/280531698_Robust_Threshold_Elliptic_Curve_Digital_Signature
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// generate shared random secret e for given t
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let n = artifacts.id_numbers.len();
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assert!(t * 2 + 1 <= n);
|
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let e_artifacts = run_key_generation(t, n, Some(artifacts.id_numbers.clone()), None);
|
||||
|
||||
// generate shares of zero for 2 * t threshold
|
||||
let z_artifacts = run_zero_key_generation(2 * t, n, &artifacts.id_numbers);
|
||||
|
||||
// each player computes && broadcast u[i] = x[i] * e[i] + z[i]
|
||||
let ui: Vec<_> = (0..n).map(|i| compute_ecdsa_inversed_secret_coeff_share(&artifacts.secret_shares[i],
|
||||
&e_artifacts.secret_shares[i],
|
||||
&z_artifacts.secret_shares[i]).unwrap()).collect();
|
||||
|
||||
// players can interpolate the polynomial of degree 2t and compute u && inv(u):
|
||||
let u_inv = compute_ecdsa_inversed_secret_coeff_from_shares(t,
|
||||
&artifacts.id_numbers.iter().take(2*t + 1).cloned().collect::<Vec<_>>(),
|
||||
&ui.iter().take(2*t + 1).cloned().collect::<Vec<_>>()).unwrap();
|
||||
|
||||
// each player Pi computes his share of inv(x) as e[i] * inv(u)
|
||||
let x_inv_shares: Vec<_> = (0..n).map(|i| {
|
||||
let mut x_inv_share = e_artifacts.secret_shares[i].clone();
|
||||
x_inv_share.mul(&u_inv).unwrap();
|
||||
x_inv_share
|
||||
}).collect();
|
||||
|
||||
x_inv_shares
|
||||
}
|
||||
|
||||
pub fn do_encryption_and_decryption(t: usize, joint_public: &Public, id_numbers: &[Secret], secret_shares: &[Secret], joint_secret: Option<&Secret>, document_secret_plain: Public) -> (Public, Public) {
|
||||
// === PART2: encryption using joint public key ===
|
||||
|
||||
@ -576,7 +778,7 @@ pub mod tests {
|
||||
let test_cases = [(0, 2), (1, 2), (1, 3), (2, 3), (1, 4), (2, 4), (3, 4), (1, 5), (2, 5), (3, 5), (4, 5),
|
||||
(1, 10), (2, 10), (3, 10), (4, 10), (5, 10), (6, 10), (7, 10), (8, 10), (9, 10)];
|
||||
for &(t, n) in &test_cases {
|
||||
let artifacts = run_key_generation(t, n, None);
|
||||
let artifacts = run_key_generation(t, n, None, None);
|
||||
|
||||
// compute joint private key [just for test]
|
||||
let joint_secret = compute_joint_secret(artifacts.polynoms1.iter().map(|p| &p[0])).unwrap();
|
||||
@ -608,7 +810,7 @@ pub mod tests {
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn full_signature_math_session() {
|
||||
fn full_schnorr_signature_math_session() {
|
||||
let test_cases = [(0, 1), (0, 2), (1, 2), (1, 3), (2, 3), (1, 4), (2, 4), (3, 4), (1, 5), (2, 5), (3, 5), (4, 5),
|
||||
(1, 10), (2, 10), (3, 10), (4, 10), (5, 10), (6, 10), (7, 10), (8, 10), (9, 10)];
|
||||
for &(t, n) in &test_cases {
|
||||
@ -617,7 +819,7 @@ pub mod tests {
|
||||
|
||||
// === MiDS-S algorithm ===
|
||||
// setup: all nodes share master secret key && every node knows master public key
|
||||
let artifacts = run_key_generation(t, n, None);
|
||||
let artifacts = run_key_generation(t, n, None, None);
|
||||
|
||||
// in this gap (not related to math):
|
||||
// master node should ask every other node if it is able to do a signing
|
||||
@ -628,7 +830,7 @@ pub mod tests {
|
||||
|
||||
// step 1: run DKG to generate one-time secret key (nonce)
|
||||
let id_numbers = artifacts.id_numbers.iter().cloned().take(n).collect();
|
||||
let one_time_artifacts = run_key_generation(t, n, Some(id_numbers));
|
||||
let one_time_artifacts = run_key_generation(t, n, Some(id_numbers), None);
|
||||
|
||||
// step 2: message hash && x coordinate of one-time public value are combined
|
||||
let combined_hash = combine_message_hash_with_public(&message_hash, &one_time_artifacts.joint_public).unwrap();
|
||||
@ -681,12 +883,67 @@ pub mod tests {
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn full_ecdsa_signature_math_session() {
|
||||
let test_cases = [(2, 5), (2, 6), (3, 11), (4, 11)];
|
||||
for &(t, n) in &test_cases {
|
||||
// values that can be hardcoded
|
||||
let joint_secret: Secret = Random.generate().unwrap().secret().clone();
|
||||
let joint_nonce: Secret = Random.generate().unwrap().secret().clone();
|
||||
let message_hash: H256 = H256::random();
|
||||
|
||||
// convert message hash to EC scalar
|
||||
let message_hash_scalar = to_scalar(message_hash.clone()).unwrap();
|
||||
|
||||
// generate secret key shares
|
||||
let artifacts = run_key_generation(t, n, None, Some(joint_secret));
|
||||
|
||||
// generate nonce shares
|
||||
let nonce_artifacts = run_key_generation(t, n, Some(artifacts.id_numbers.clone()), Some(joint_nonce));
|
||||
|
||||
// compute nonce public
|
||||
// x coordinate (mapped to EC field) of this public is the r-portion of signature
|
||||
let nonce_public_shares: Vec<_> = (0..n).map(|i| compute_public_share(&nonce_artifacts.polynoms1[i][0]).unwrap()).collect();
|
||||
let nonce_public = compute_joint_public(nonce_public_shares.iter()).unwrap();
|
||||
let signature_r = compute_ecdsa_r(&nonce_public).unwrap();
|
||||
|
||||
// compute shares of inv(nonce) so that both nonce && inv(nonce) are still unknown to all nodes
|
||||
let nonce_inv_shares = run_reciprocal_protocol(t, &nonce_artifacts);
|
||||
|
||||
// compute multiplication of secret-shares * inv-nonce-shares
|
||||
let mul_shares = run_multiplication_protocol(t, &artifacts.secret_shares, &nonce_inv_shares);
|
||||
|
||||
// compute shares for s portion of signature: nonce_inv * (message_hash + secret * signature_r)
|
||||
// every node broadcasts this share
|
||||
let double_t = 2 * t;
|
||||
let signature_s_shares: Vec<_> = (0..double_t+1).map(|i| compute_ecdsa_s_share(
|
||||
&nonce_inv_shares[i],
|
||||
&mul_shares[i],
|
||||
&signature_r,
|
||||
&message_hash_scalar
|
||||
).unwrap()).collect();
|
||||
|
||||
// compute signature_s from received shares
|
||||
let signature_s = compute_ecdsa_s(t,
|
||||
&signature_s_shares,
|
||||
&artifacts.id_numbers.iter().take(double_t + 1).cloned().collect::<Vec<_>>()
|
||||
).unwrap();
|
||||
|
||||
// check signature
|
||||
let signature_actual = serialize_ecdsa_signature(&nonce_public, signature_r, signature_s);
|
||||
let joint_secret = compute_joint_secret(artifacts.polynoms1.iter().map(|p| &p[0])).unwrap();
|
||||
let joint_secret_pair = KeyPair::from_secret(joint_secret).unwrap();
|
||||
assert_eq!(recover(&signature_actual, &message_hash).unwrap(), *joint_secret_pair.public());
|
||||
assert!(verify_public(joint_secret_pair.public(), &signature_actual, &message_hash).unwrap());
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn full_generation_math_session_with_refreshing_shares() {
|
||||
let test_cases = vec![(1, 4), (6, 10)];
|
||||
for (t, n) in test_cases {
|
||||
// generate key using t-of-n session
|
||||
let artifacts1 = run_key_generation(t, n, None);
|
||||
let artifacts1 = run_key_generation(t, n, None, None);
|
||||
let joint_secret1 = compute_joint_secret(artifacts1.polynoms1.iter().map(|p1| &p1[0])).unwrap();
|
||||
|
||||
// let's say we want to refresh existing secret shares
|
||||
@ -710,7 +967,7 @@ pub mod tests {
|
||||
let test_cases = vec![(1, 3), (1, 4), (6, 10)];
|
||||
for (t, n) in test_cases {
|
||||
// generate key using t-of-n session
|
||||
let artifacts1 = run_key_generation(t, n, None);
|
||||
let artifacts1 = run_key_generation(t, n, None, None);
|
||||
let joint_secret1 = compute_joint_secret(artifacts1.polynoms1.iter().map(|p1| &p1[0])).unwrap();
|
||||
|
||||
// let's say we want to include additional couple of servers to the set
|
||||
@ -733,7 +990,8 @@ pub mod tests {
|
||||
let (t, n) = (3, 5);
|
||||
|
||||
// generate key using t-of-n session
|
||||
let artifacts1 = run_key_generation(t, n, None);
|
||||
let artifacts1 = run_key_generation(t, n, None, None);
|
||||
|
||||
let joint_secret1 = compute_joint_secret(artifacts1.polynoms1.iter().map(|p1| &p1[0])).unwrap();
|
||||
|
||||
// let's say we want to decrease threshold so that it becames (t-1)-of-n
|
||||
@ -751,4 +1009,75 @@ pub mod tests {
|
||||
&artifacts3.id_numbers.iter().take(new_t + 1).collect::<Vec<_>>()).unwrap();
|
||||
assert_eq!(joint_secret1, joint_secret3);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn full_zero_secret_generation_math_session() {
|
||||
let test_cases = vec![(1, 4), (2, 4)];
|
||||
for (t, n) in test_cases {
|
||||
// run joint zero generation session
|
||||
let id_numbers: Vec<_> = (0..n).map(|_| generate_random_scalar().unwrap()).collect();
|
||||
let artifacts = run_zero_key_generation(t, n, &id_numbers);
|
||||
|
||||
// check that zero secret is generated
|
||||
// we can't compute secrets sum here, because result will be zero (invalid secret, unsupported by SECP256k1)
|
||||
// so just use complement trick: x + (-x) = 0
|
||||
// TODO [Refac]: switch to SECP256K1-free scalar EC arithmetic
|
||||
let partial_joint_secret = compute_secret_sum(artifacts.polynoms1.iter().take(n - 1).map(|p| &p[0])).unwrap();
|
||||
let mut partial_joint_secret_complement = artifacts.polynoms1[n - 1][0].clone();
|
||||
partial_joint_secret_complement.neg().unwrap();
|
||||
assert_eq!(partial_joint_secret, partial_joint_secret_complement);
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn full_generation_with_multiplication() {
|
||||
let test_cases = vec![(1, 3), (2, 5), (2, 7), (3, 8)];
|
||||
for (t, n) in test_cases {
|
||||
// generate two shared secrets
|
||||
let artifacts1 = run_key_generation(t, n, None, None);
|
||||
let artifacts2 = run_key_generation(t, n, Some(artifacts1.id_numbers.clone()), None);
|
||||
|
||||
// multiplicate original secrets
|
||||
let joint_secret1 = compute_joint_secret(artifacts1.polynoms1.iter().map(|p| &p[0])).unwrap();
|
||||
let joint_secret2 = compute_joint_secret(artifacts2.polynoms1.iter().map(|p| &p[0])).unwrap();
|
||||
let mut expected_joint_secret_mul = joint_secret1;
|
||||
expected_joint_secret_mul.mul(&joint_secret2).unwrap();
|
||||
|
||||
// run multiplication protocol
|
||||
let joint_secret_mul_shares = run_multiplication_protocol(t, &artifacts1.secret_shares, &artifacts2.secret_shares);
|
||||
|
||||
// calculate actual secrets multiplication
|
||||
let double_t = t * 2;
|
||||
let actual_joint_secret_mul = compute_joint_secret_from_shares(double_t,
|
||||
&joint_secret_mul_shares.iter().take(double_t + 1).collect::<Vec<_>>(),
|
||||
&artifacts1.id_numbers.iter().take(double_t + 1).collect::<Vec<_>>()).unwrap();
|
||||
|
||||
assert_eq!(actual_joint_secret_mul, expected_joint_secret_mul);
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn full_generation_with_reciprocal() {
|
||||
let test_cases = vec![(1, 3), (2, 5), (2, 7), (2, 7), (3, 8)];
|
||||
for (t, n) in test_cases {
|
||||
// generate shared secret
|
||||
let artifacts = run_key_generation(t, n, None, None);
|
||||
|
||||
// calculate inversion of original shared secret
|
||||
let joint_secret = compute_joint_secret(artifacts.polynoms1.iter().map(|p| &p[0])).unwrap();
|
||||
let mut expected_joint_secret_inv = joint_secret.clone();
|
||||
expected_joint_secret_inv.inv().unwrap();
|
||||
|
||||
// run inversion protocol
|
||||
let reciprocal_shares = run_reciprocal_protocol(t, &artifacts);
|
||||
|
||||
// calculate actual secret inversion
|
||||
let double_t = t * 2;
|
||||
let actual_joint_secret_inv = compute_joint_secret_from_shares(double_t,
|
||||
&reciprocal_shares.iter().take(double_t + 1).collect::<Vec<_>>(),
|
||||
&artifacts.id_numbers.iter().take(double_t + 1).collect::<Vec<_>>()).unwrap();
|
||||
|
||||
assert_eq!(actual_joint_secret_inv, expected_joint_secret_inv);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user