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hbbft
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separated crypto module into its own crate

This commit is contained in:
Vladimir Komendantskiy 2018-07-30 13:39:27 +01:00
parent 0e7055f8eb
commit 77ed1d50d4
24 changed files with 24 additions and 1636 deletions
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1
Cargo.toml
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@ -32,6 +32,7 @@ reed-solomon-erasure = "3.1.0"
ring = "^0.12"
serde = "1.0.55"
serde_derive = "1.0.55"
threshold_crypto = { git = "https://github.com/poanetwork/threshold_crypto" }
[dev-dependencies]
colored = "1.6"

1
examples/consensus-node.rs
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@ -11,6 +11,7 @@ extern crate hbbft;
extern crate log;
extern crate pairing;
extern crate serde;
extern crate threshold_crypto as crypto;
mod network;

7
examples/network/node.rs
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@ -34,7 +34,6 @@
//! the consensus `result` is not an error then every successfully terminated
//! consensus node will be the same `result`.
use crossbeam;
use std::collections::{BTreeSet, HashSet};
use std::fmt::Debug;
use std::marker::{Send, Sync};
@ -42,9 +41,11 @@ use std::net::SocketAddr;
use std::sync::Arc;
use std::{io, iter, process, thread, time};
use crossbeam;
use crypto::poly::Poly;
use crypto::{SecretKey, SecretKeySet};
use hbbft::broadcast::{Broadcast, BroadcastMessage};
use hbbft::crypto::poly::Poly;
use hbbft::crypto::{SecretKey, SecretKeySet};
use hbbft::messaging::{DistAlgorithm, NetworkInfo, SourcedMessage};
use network::commst;
use network::connection;

13
src/crypto/error.rs
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@ -1,13 +0,0 @@
//! Crypto errors.
/// A crypto error.
#[derive(Clone, Eq, PartialEq, Debug, Fail)]
pub enum Error {
#[fail(display = "Not enough signature shares")]
NotEnoughShares,
#[fail(display = "Signature shares contain a duplicated index")]
DuplicateEntry,
}
/// A crypto result.
pub type Result<T> = ::std::result::Result<T, Error>;

55
src/crypto/into_fr.rs
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@ -1,55 +0,0 @@
use pairing::bls12_381::Fr;
use pairing::{Field, PrimeField};
/// A conversion into an element of the field `Fr`.
pub trait IntoFr: Copy {
fn into_fr(self) -> Fr;
}
impl IntoFr for Fr {
fn into_fr(self) -> Fr {
self
}
}
impl IntoFr for u64 {
fn into_fr(self) -> Fr {
Fr::from_repr(self.into()).expect("modulus is greater than u64::MAX")
}
}
impl IntoFr for usize {
fn into_fr(self) -> Fr {
(self as u64).into_fr()
}
}
impl IntoFr for i32 {
fn into_fr(self) -> Fr {
if self >= 0 {
(self as u64).into_fr()
} else {
let mut result = ((-self) as u64).into_fr();
result.negate();
result
}
}
}
impl IntoFr for i64 {
fn into_fr(self) -> Fr {
if self >= 0 {
(self as u64).into_fr()
} else {
let mut result = ((-self) as u64).into_fr();
result.negate();
result
}
}
}
impl<'a, T: IntoFr> IntoFr for &'a T {
fn into_fr(self) -> Fr {
(*self).into_fr()
}
}

664
src/crypto/mod.rs
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@ -1,664 +0,0 @@
// Clippy warns that it's dangerous to derive `PartialEq` and explicitly implement `Hash`, but the
// `pairing::bls12_381` types don't implement `Hash`, so we can't derive it.
#![cfg_attr(feature = "cargo-clippy", allow(derive_hash_xor_eq))]
pub mod error;
mod into_fr;
pub mod poly;
pub mod serde_impl;
use std::fmt;
use std::hash::{Hash, Hasher};
use std::ptr::write_volatile;
use byteorder::{BigEndian, ByteOrder};
use init_with::InitWith;
use pairing::bls12_381::{Bls12, Fr, G1, G1Affine, G2, G2Affine};
use pairing::{CurveAffine, CurveProjective, Engine, Field};
use rand::{ChaChaRng, OsRng, Rng, SeedableRng};
use ring::digest;
use self::error::{Error, Result};
use self::into_fr::IntoFr;
use self::poly::{Commitment, Poly};
use fmt::HexBytes;
/// The number of words (`u32`) in a ChaCha RNG seed.
const CHACHA_RNG_SEED_SIZE: usize = 8;
const ERR_OS_RNG: &str = "could not initialize the OS random number generator";
/// A public key.
#[derive(Deserialize, Serialize, Copy, Clone, PartialEq, Eq)]
pub struct PublicKey(#[serde(with = "serde_impl::projective")] G1);
impl Hash for PublicKey {
fn hash<H: Hasher>(&self, state: &mut H) {
self.0.into_affine().into_compressed().as_ref().hash(state);
}
}
impl fmt::Debug for PublicKey {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let uncomp = self.0.into_affine().into_uncompressed();
let bytes = uncomp.as_ref();
write!(f, "PublicKey({:?})", HexBytes(bytes))
}
}
impl PublicKey {
/// Returns `true` if the signature matches the element of `G2`.
pub fn verify_g2<H: Into<G2Affine>>(&self, sig: &Signature, hash: H) -> bool {
Bls12::pairing(self.0, hash) == Bls12::pairing(G1Affine::one(), sig.0)
}
/// Returns `true` if the signature matches the message.
pub fn verify<M: AsRef<[u8]>>(&self, sig: &Signature, msg: M) -> bool {
self.verify_g2(sig, hash_g2(msg))
}
/// Encrypts the message.
pub fn encrypt<M: AsRef<[u8]>>(&self, msg: M) -> Ciphertext {
let r: Fr = OsRng::new().expect(ERR_OS_RNG).gen();
let u = G1Affine::one().mul(r);
let v: Vec<u8> = {
let g = self.0.into_affine().mul(r);
xor_vec(&hash_bytes(g, msg.as_ref().len()), msg.as_ref())
};
let w = hash_g1_g2(u, &v).into_affine().mul(r);
Ciphertext(u, v, w)
}
/// Returns a byte string representation of the public key.
pub fn to_bytes(&self) -> Vec<u8> {
self.0.into_affine().into_compressed().as_ref().to_vec()
}
}
/// A public key share.
#[derive(Deserialize, Serialize, Clone, PartialEq, Eq, Hash)]
pub struct PublicKeyShare(PublicKey);
impl fmt::Debug for PublicKeyShare {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let uncomp = (self.0).0.into_affine().into_uncompressed();
let bytes = uncomp.as_ref();
write!(f, "PublicKeyShare({:?})", HexBytes(bytes))
}
}
impl PublicKeyShare {
/// Returns `true` if the signature matches the element of `G2`.
pub fn verify_g2<H: Into<G2Affine>>(&self, sig: &SignatureShare, hash: H) -> bool {
self.0.verify_g2(&sig.0, hash)
}
/// Returns `true` if the signature matches the message.
pub fn verify<M: AsRef<[u8]>>(&self, sig: &SignatureShare, msg: M) -> bool {
self.verify_g2(sig, hash_g2(msg))
}
/// Returns `true` if the decryption share matches the ciphertext.
pub fn verify_decryption_share(&self, share: &DecryptionShare, ct: &Ciphertext) -> bool {
let Ciphertext(ref u, ref v, ref w) = *ct;
let hash = hash_g1_g2(*u, v);
Bls12::pairing(share.0, hash) == Bls12::pairing((self.0).0, *w)
}
/// Returns a byte string representation of the public key share.
pub fn to_bytes(&self) -> Vec<u8> {
self.0.to_bytes()
}
}
/// A signature.
// Note: Random signatures can be generated for testing.
#[derive(Deserialize, Serialize, Clone, PartialEq, Eq, Rand)]
pub struct Signature(#[serde(with = "serde_impl::projective")] G2);
impl fmt::Debug for Signature {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let uncomp = self.0.into_affine().into_uncompressed();
let bytes = uncomp.as_ref();
write!(f, "Signature({:?})", HexBytes(bytes))
}
}
impl Hash for Signature {
fn hash<H: Hasher>(&self, state: &mut H) {
self.0.into_affine().into_compressed().as_ref().hash(state);
}
}
impl Signature {
pub fn parity(&self) -> bool {
let uncomp = self.0.into_affine().into_uncompressed();
let bytes = uncomp.as_ref();
let xor_bytes: u8 = bytes.iter().fold(0, |result, byte| result ^ byte);
let parity = 0 != xor_bytes.count_ones() % 2;
debug!("Signature: {:?}, output: {}", HexBytes(bytes), parity);
parity
}
}
/// A signature share.
// Note: Random signature shares can be generated for testing.
#[derive(Deserialize, Serialize, Clone, PartialEq, Eq, Rand, Hash)]
pub struct SignatureShare(pub(crate) Signature);
impl fmt::Debug for SignatureShare {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let uncomp = (self.0).0.into_affine().into_uncompressed();
let bytes = uncomp.as_ref();
write!(f, "SignatureShare({:?})", HexBytes(bytes))
}
}
/// A secret key.
#[derive(Clone, PartialEq, Eq, Rand)]
pub struct SecretKey(Fr);
impl fmt::Debug for SecretKey {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let uncomp = self.public_key().0.into_affine().into_uncompressed();
let bytes = uncomp.as_ref();
write!(f, "SecretKey({:?})", HexBytes(bytes))
}
}
impl Default for SecretKey {
fn default() -> Self {
SecretKey(Fr::zero())
}
}
impl Drop for SecretKey {
fn drop(&mut self) {
let ptr = self as *mut Self;
unsafe {
write_volatile(ptr, SecretKey::default());
}
}
}
impl SecretKey {
/// Creates a secret key from an existing value
pub fn from_value(f: Fr) -> Self {
SecretKey(f)
}
/// Returns the matching public key.
pub fn public_key(&self) -> PublicKey {
PublicKey(G1Affine::one().mul(self.0))
}
/// Signs the given element of `G2`.
pub fn sign_g2<H: Into<G2Affine>>(&self, hash: H) -> Signature {
Signature(hash.into().mul(self.0))
}
/// Signs the given message.
pub fn sign<M: AsRef<[u8]>>(&self, msg: M) -> Signature {
self.sign_g2(hash_g2(msg))
}
/// Returns the decrypted text, or `None`, if the ciphertext isn't valid.
pub fn decrypt(&self, ct: &Ciphertext) -> Option<Vec<u8>> {
if !ct.verify() {
return None;
}
let Ciphertext(ref u, ref v, _) = *ct;
let g = u.into_affine().mul(self.0);
Some(xor_vec(&hash_bytes(g, v.len()), v))
}
}
/// A secret key share.
#[derive(Clone, PartialEq, Eq, Rand, Default)]
pub struct SecretKeyShare(SecretKey);
impl fmt::Debug for SecretKeyShare {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let uncomp = self.0.public_key().0.into_affine().into_uncompressed();
let bytes = uncomp.as_ref();
write!(f, "SecretKeyShare({:?})", HexBytes(bytes))
}
}
impl SecretKeyShare {
/// Creates a secret key share from an existing value
pub fn from_value(f: Fr) -> Self {
SecretKeyShare(SecretKey::from_value(f))
}
/// Returns the matching public key share.
pub fn public_key_share(&self) -> PublicKeyShare {
PublicKeyShare(self.0.public_key())
}
/// Signs the given element of `G2`.
pub fn sign_g2<H: Into<G2Affine>>(&self, hash: H) -> SignatureShare {
SignatureShare(self.0.sign_g2(hash))
}
/// Signs the given message.
pub fn sign<M: AsRef<[u8]>>(&self, msg: M) -> SignatureShare {
SignatureShare(self.0.sign(msg))
}
/// Returns a decryption share, or `None`, if the ciphertext isn't valid.
pub fn decrypt_share(&self, ct: &Ciphertext) -> Option<DecryptionShare> {
if !ct.verify() {
return None;
}
Some(self.decrypt_share_no_verify(ct))
}
/// Returns a decryption share, without validating the ciphertext.
pub fn decrypt_share_no_verify(&self, ct: &Ciphertext) -> DecryptionShare {
DecryptionShare(ct.0.into_affine().mul((self.0).0))
}
}
/// An encrypted message.
#[derive(Deserialize, Serialize, Debug, Clone, PartialEq, Eq)]
pub struct Ciphertext(
#[serde(with = "serde_impl::projective")] G1,
Vec<u8>,
#[serde(with = "serde_impl::projective")] G2,
);
impl Hash for Ciphertext {
fn hash<H: Hasher>(&self, state: &mut H) {
let Ciphertext(ref u, ref v, ref w) = *self;
u.into_affine().into_compressed().as_ref().hash(state);
v.hash(state);
w.into_affine().into_compressed().as_ref().hash(state);
}
}
impl Ciphertext {
/// Returns `true` if this is a valid ciphertext. This check is necessary to prevent
/// chosen-ciphertext attacks.
pub fn verify(&self) -> bool {
let Ciphertext(ref u, ref v, ref w) = *self;
let hash = hash_g1_g2(*u, v);
Bls12::pairing(G1Affine::one(), *w) == Bls12::pairing(*u, hash)
}
}
/// A decryption share. A threshold of decryption shares can be used to decrypt a message.
#[derive(Clone, Deserialize, Serialize, Debug, PartialEq, Eq, Rand)]
pub struct DecryptionShare(#[serde(with = "serde_impl::projective")] G1);
impl Hash for DecryptionShare {
fn hash<H: Hasher>(&self, state: &mut H) {
self.0.into_affine().into_compressed().as_ref().hash(state);
}
}
/// A public key and an associated set of public key shares.
#[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Eq)]
pub struct PublicKeySet {
/// The coefficients of a polynomial whose value at `0` is the "master key", and value at
/// `i + 1` is key share number `i`.
commit: Commitment,
}
impl Hash for PublicKeySet {
fn hash<H: Hasher>(&self, state: &mut H) {
self.commit.hash(state);
}
}
impl From<Commitment> for PublicKeySet {
fn from(commit: Commitment) -> PublicKeySet {
PublicKeySet { commit }
}
}
impl PublicKeySet {
/// Returns the threshold `t`: any set of `t + 1` signature shares can be combined into a full
/// signature.
pub fn threshold(&self) -> usize {
self.commit.degree()
}
/// Returns the public key.
pub fn public_key(&self) -> PublicKey {
PublicKey(self.commit.coeff[0])
}
/// Returns the `i`-th public key share.
pub fn public_key_share<T: IntoFr>(&self, i: T) -> PublicKeyShare {
let value = self.commit.evaluate(into_fr_plus_1(i));
PublicKeyShare(PublicKey(value))
}
/// Combines the shares into a signature that can be verified with the main public key.
pub fn combine_signatures<'a, T, I>(&self, shares: I) -> Result<Signature>
where
I: IntoIterator<Item = (T, &'a SignatureShare)>,
T: IntoFr,
{
let samples = shares.into_iter().map(|(i, share)| (i, &(share.0).0));
Ok(Signature(interpolate(self.commit.degree() + 1, samples)?))
}
/// Combines the shares to decrypt the ciphertext.
pub fn decrypt<'a, T, I>(&self, shares: I, ct: &Ciphertext) -> Result<Vec<u8>>
where
I: IntoIterator<Item = (T, &'a DecryptionShare)>,
T: IntoFr,
{
let samples = shares.into_iter().map(|(i, share)| (i, &share.0));
let g = interpolate(self.commit.degree() + 1, samples)?;
Ok(xor_vec(&hash_bytes(g, ct.1.len()), &ct.1))
}
}
/// A secret key and an associated set of secret key shares.
pub struct SecretKeySet {
/// The coefficients of a polynomial whose value at `0` is the "master key", and value at
/// `i + 1` is key share number `i`.
poly: Poly,
}
impl From<Poly> for SecretKeySet {
fn from(poly: Poly) -> SecretKeySet {
SecretKeySet { poly }
}
}
impl SecretKeySet {
/// Creates a set of secret key shares, where any `threshold + 1` of them can collaboratively
/// sign and decrypt.
pub fn random<R: Rng>(threshold: usize, rng: &mut R) -> Self {
SecretKeySet {
poly: Poly::random(threshold, rng),
}
}
/// Returns the threshold `t`: any set of `t + 1` signature shares can be combined into a full
/// signature.
pub fn threshold(&self) -> usize {
self.poly.degree()
}
/// Returns the `i`-th secret key share.
pub fn secret_key_share<T: IntoFr>(&self, i: T) -> SecretKeyShare {
let value = self.poly.evaluate(into_fr_plus_1(i));
SecretKeyShare(SecretKey(value))
}
/// Returns the corresponding public key set. That information can be shared publicly.
pub fn public_keys(&self) -> PublicKeySet {
PublicKeySet {
commit: self.poly.commitment(),
}
}
/// Returns the secret master key.
#[cfg(test)]
fn secret_key(&self) -> SecretKey {
SecretKey(self.poly.evaluate(0))
}
}
/// Returns a hash of the given message in `G2`.
fn hash_g2<M: AsRef<[u8]>>(msg: M) -> G2 {
let digest = digest::digest(&digest::SHA256, msg.as_ref());
let seed = <[u32; CHACHA_RNG_SEED_SIZE]>::init_with_indices(|i| {
BigEndian::read_u32(&digest.as_ref()[(4 * i)..(4 * i + 4)])
});
let mut rng = ChaChaRng::from_seed(&seed);
rng.gen()
}
/// Returns a hash of the group element and message, in the second group.
fn hash_g1_g2<M: AsRef<[u8]>>(g1: G1, msg: M) -> G2 {
// If the message is large, hash it, otherwise copy it.
// TODO: Benchmark and optimize the threshold.
let mut msg = if msg.as_ref().len() > 64 {
let digest = digest::digest(&digest::SHA256, msg.as_ref());
digest.as_ref().to_vec()
} else {
msg.as_ref().to_vec()
};
msg.extend(g1.into_affine().into_compressed().as_ref());
hash_g2(&msg)
}
/// Returns a hash of the group element with the specified length in bytes.
fn hash_bytes(g1: G1, len: usize) -> Vec<u8> {
let digest = digest::digest(&digest::SHA256, g1.into_affine().into_compressed().as_ref());
let seed = <[u32; CHACHA_RNG_SEED_SIZE]>::init_with_indices(|i| {
BigEndian::read_u32(&digest.as_ref()[(4 * i)..(4 * i + 4)])
});
let mut rng = ChaChaRng::from_seed(&seed);
rng.gen_iter().take(len).collect()
}
/// Returns the bitwise xor.
fn xor_vec(x: &[u8], y: &[u8]) -> Vec<u8> {
x.iter().zip(y).map(|(a, b)| a ^ b).collect()
}
/// Given a list of `t` samples `(i - 1, f(i) * g)` for a polynomial `f` of degree `t - 1`, and a
/// group generator `g`, returns `f(0) * g`.
fn interpolate<'a, C, T, I>(t: usize, items: I) -> Result<C>
where
C: CurveProjective<Scalar = Fr>,
I: IntoIterator<Item = (T, &'a C)>,
T: IntoFr,
{
let samples: Vec<_> = items
.into_iter()
.map(|(i, sample)| (into_fr_plus_1(i), sample))
.collect();
if samples.len() < t {
return Err(Error::NotEnoughShares);
}
let mut result = C::zero();
let mut indexes = Vec::new();
for (x, sample) in samples.iter().take(t) {
if indexes.contains(x) {
return Err(Error::DuplicateEntry);
}
indexes.push(x.clone());
// Compute the value at 0 of the Lagrange polynomial that is `0` at the other data
// points but `1` at `x`.
let mut l0 = C::Scalar::one();
for (x0, _) in samples.iter().take(t).filter(|(x0, _)| x0 != x) {
let mut denom = *x0;
denom.sub_assign(x);
l0.mul_assign(x0);
l0.mul_assign(&denom.inverse().expect("indices are different"));
}
result.add_assign(&sample.into_affine().mul(l0));
}
Ok(result)
}
fn into_fr_plus_1<I: IntoFr>(x: I) -> Fr {
let mut result = Fr::one();
result.add_assign(&x.into_fr());
result
}
#[cfg(test)]
mod tests {
use super::*;
use std::collections::BTreeMap;
use rand::{self, random};
#[test]
fn test_simple_sig() {
let sk0: SecretKey = random();
let sk1: SecretKey = random();
let pk0 = sk0.public_key();
let msg0 = b"Real news";
let msg1 = b"Fake news";
assert!(pk0.verify(&sk0.sign(msg0), msg0));
assert!(!pk0.verify(&sk1.sign(msg0), msg0)); // Wrong key.
assert!(!pk0.verify(&sk0.sign(msg1), msg0)); // Wrong message.
}
#[test]
fn test_threshold_sig() {
let mut rng = rand::thread_rng();
let sk_set = SecretKeySet::random(3, &mut rng);
let pk_set = sk_set.public_keys();
// Make sure the keys are different, and the first coefficient is the main key.
assert_ne!(pk_set.public_key(), pk_set.public_key_share(0).0);
assert_ne!(pk_set.public_key(), pk_set.public_key_share(1).0);
assert_ne!(pk_set.public_key(), pk_set.public_key_share(2).0);
// Make sure we don't hand out the main secret key to anyone.
assert_ne!(sk_set.secret_key(), sk_set.secret_key_share(0).0);
assert_ne!(sk_set.secret_key(), sk_set.secret_key_share(1).0);
assert_ne!(sk_set.secret_key(), sk_set.secret_key_share(2).0);
let msg = "Totally real news";
// The threshold is 3, so 4 signature shares will suffice to recreate the share.
let sigs: BTreeMap<_, _> = [5, 8, 7, 10]
.into_iter()
.map(|i| (*i, sk_set.secret_key_share(*i).sign(msg)))
.collect();
// Each of the shares is a valid signature matching its public key share.
for (i, sig) in &sigs {
assert!(pk_set.public_key_share(*i).verify(sig, msg));
}
// Combined, they produce a signature matching the main public key.
let sig = pk_set.combine_signatures(&sigs).expect("signatures match");
assert!(pk_set.public_key().verify(&sig, msg));
// A different set of signatories produces the same signature.
let sigs2: BTreeMap<_, _> = [42, 43, 44, 45]
.into_iter()
.map(|i| (*i, sk_set.secret_key_share(*i).sign(msg)))
.collect();
let sig2 = pk_set.combine_signatures(&sigs2).expect("signatures match");
assert_eq!(sig, sig2);
}
#[test]
fn test_simple_enc() {
let sk_bob: SecretKey = random();
let sk_eve: SecretKey = random();
let pk_bob = sk_bob.public_key();
let msg = b"Muffins in the canteen today! Don't tell Eve!";
let ciphertext = pk_bob.encrypt(&msg[..]);
assert!(ciphertext.verify());
// Bob can decrypt the message.
let decrypted = sk_bob.decrypt(&ciphertext).expect("valid ciphertext");
assert_eq!(msg[..], decrypted[..]);
// Eve can't.
let decrypted_eve = sk_eve.decrypt(&ciphertext).expect("valid ciphertext");
assert_ne!(msg[..], decrypted_eve[..]);
// Eve tries to trick Bob into decrypting `msg` xor `v`, but it doesn't validate.
let Ciphertext(u, v, w) = ciphertext;
let fake_ciphertext = Ciphertext(u, vec![0; v.len()], w);
assert!(!fake_ciphertext.verify());
assert_eq!(None, sk_bob.decrypt(&fake_ciphertext));
}
#[test]
fn test_threshold_enc() {
let mut rng = rand::thread_rng();
let sk_set = SecretKeySet::random(3, &mut rng);
let pk_set = sk_set.public_keys();
let msg = b"Totally real news";
let ciphertext = pk_set.public_key().encrypt(&msg[..]);
// The threshold is 3, so 4 signature shares will suffice to decrypt.
let shares: BTreeMap<_, _> = [5, 8, 7, 10]
.into_iter()
.map(|i| {
let ski = sk_set.secret_key_share(*i);
let share = ski.decrypt_share(&ciphertext).expect("ciphertext is valid");
(*i, share)
})
.collect();
// Each of the shares is valid matching its public key share.
for (i, share) in &shares {
pk_set
.public_key_share(*i)
.verify_decryption_share(share, &ciphertext);
}
// Combined, they can decrypt the message.
let decrypted = pk_set
.decrypt(&shares, &ciphertext)
.expect("decryption shares match");
assert_eq!(msg[..], decrypted[..]);
}
/// Some basic sanity checks for the `hash_g2` function.
#[test]
fn test_hash_g2() {
let mut rng = rand::thread_rng();
let msg: Vec<u8> = (0..1000).map(|_| rng.gen()).collect();
let msg_end0: Vec<u8> = msg.iter().chain(b"end0").cloned().collect();
let msg_end1: Vec<u8> = msg.iter().chain(b"end1").cloned().collect();
assert_eq!(hash_g2(&msg), hash_g2(&msg));
assert_ne!(hash_g2(&msg), hash_g2(&msg_end0));
assert_ne!(hash_g2(&msg_end0), hash_g2(&msg_end1));
}
/// Some basic sanity checks for the `hash_g1_g2` function.
#[test]
fn test_hash_g1_g2() {
let mut rng = rand::thread_rng();
let msg: Vec<u8> = (0..1000).map(|_| rng.gen()).collect();
let msg_end0: Vec<u8> = msg.iter().chain(b"end0").cloned().collect();
let msg_end1: Vec<u8> = msg.iter().chain(b"end1").cloned().collect();
let g0 = rng.gen();
let g1 = rng.gen();
assert_eq!(hash_g1_g2(g0, &msg), hash_g1_g2(g0, &msg));
assert_ne!(hash_g1_g2(g0, &msg), hash_g1_g2(g0, &msg_end0));
assert_ne!(hash_g1_g2(g0, &msg_end0), hash_g1_g2(g0, &msg_end1));
assert_ne!(hash_g1_g2(g0, &msg), hash_g1_g2(g1, &msg));
}
/// Some basic sanity checks for the `hash_bytes` function.
#[test]
fn test_hash_bytes() {
let mut rng = rand::thread_rng();
let g0 = rng.gen();
let g1 = rng.gen();
let hash = hash_bytes;
assert_eq!(hash(g0, 5), hash(g0, 5));
assert_ne!(hash(g0, 5), hash(g1, 5));
assert_eq!(5, hash(g0, 5).len());
assert_eq!(6, hash(g0, 6).len());
assert_eq!(20, hash(g0, 20).len());
}
#[test]
fn test_serde() {
use bincode;
let sk: SecretKey = random();
let sig = sk.sign("Please sign here: ______");
let pk = sk.public_key();
let ser_pk = bincode::serialize(&pk).expect("serialize public key");
let deser_pk = bincode::deserialize(&ser_pk).expect("deserialize public key");
assert_eq!(pk, deser_pk);
let ser_sig = bincode::serialize(&sig).expect("serialize signature");
let deser_sig = bincode::deserialize(&ser_sig).expect("deserialize signature");
assert_eq!(sig, deser_sig);
}
}

689
src/crypto/poly.rs
View File

@ -1,689 +0,0 @@
//! Utilities for distributed key generation: uni- and bivariate polynomials and commitments.
//!
//! If `G` is a group of prime order `r` (written additively), and `g` is a generator, then
//! multiplication by integers factors through `r`, so the map `x -> x * g` (the sum of `x`
//! copies of `g`) is a homomorphism from the field `Fr` of integers modulo `r` to `G`. If the
//! _discrete logarithm_ is hard, i.e. it is infeasible to reverse this map, then `x * g` can be
//! considered a _commitment_ to `x`: By publishing it, you can guarantee to others that you won't
//! change your mind about the value `x`, without revealing it.
//!
//! This concept extends to polynomials: If you have a polynomial `f` over `Fr`, defined as
//! `a * X * X + b * X + c`, you can publish `a * g`, `b * g` and `c * g`. Then others will be able
//! to verify any single value `f(x)` of the polynomial without learning the original polynomial,
//! because `f(x) * g == x * x * (a * g) + x * (b * g) + (c * g)`. Only after learning three (in
//! general `degree + 1`) values, they can interpolate `f` itself.
//!
//! This module defines univariate polynomials (in one variable) and _symmetric_ bivariate
//! polynomials (in two variables) over a field `Fr`, as well as their _commitments_ in `G`.
use std::borrow::Borrow;
use std::hash::{Hash, Hasher};
use std::ptr::write_volatile;
use std::{cmp, iter, ops};
use pairing::bls12_381::{Fr, G1, G1Affine};
use pairing::{CurveAffine, CurveProjective, Field};
use rand::Rng;
use super::IntoFr;
/// A univariate polynomial in the prime field.
#[derive(Clone, Debug, Serialize, Deserialize, PartialEq, Eq)]
pub struct Poly {
/// The coefficients of a polynomial.
#[serde(with = "super::serde_impl::field_vec")]
pub(super) coeff: Vec<Fr>,
}
impl<B: Borrow<Poly>> ops::AddAssign<B> for Poly {
fn add_assign(&mut self, rhs: B) {
let len = cmp::max(self.coeff.len(), rhs.borrow().coeff.len());
self.coeff.resize(len, Fr::zero());
for (self_c, rhs_c) in self.coeff.iter_mut().zip(&rhs.borrow().coeff) {
self_c.add_assign(rhs_c);
}
self.remove_zeros();
}
}
impl<'a, B: Borrow<Poly>> ops::Add<B> for &'a Poly {
type Output = Poly;
fn add(self, rhs: B) -> Poly {
(*self).clone() + rhs
}
}
impl<B: Borrow<Poly>> ops::Add<B> for Poly {
type Output = Poly;
fn add(mut self, rhs: B) -> Poly {
self += rhs;
self
}
}
impl<'a> ops::Add<Fr> for Poly {
type Output = Poly;
fn add(mut self, rhs: Fr) -> Self::Output {
if self.coeff.is_empty() {
if !rhs.is_zero() {
self.coeff.push(rhs);
}
} else {
self.coeff[0].add_assign(&rhs);
self.remove_zeros();
}
self
}
}
impl<'a> ops::Add<u64> for Poly {
type Output = Poly;
fn add(self, rhs: u64) -> Self::Output {
self + rhs.into_fr()
}
}
impl<B: Borrow<Poly>> ops::SubAssign<B> for Poly {
fn sub_assign(&mut self, rhs: B) {
let len = cmp::max(self.coeff.len(), rhs.borrow().coeff.len());
self.coeff.resize(len, Fr::zero());
for (self_c, rhs_c) in self.coeff.iter_mut().zip(&rhs.borrow().coeff) {
self_c.sub_assign(rhs_c);
}
self.remove_zeros();
}
}
impl<'a, B: Borrow<Poly>> ops::Sub<B> for &'a Poly {
type Output = Poly;
fn sub(self, rhs: B) -> Poly {
(*self).clone() - rhs
}
}
impl<B: Borrow<Poly>> ops::Sub<B> for Poly {
type Output = Poly;
fn sub(mut self, rhs: B) -> Poly {
self -= rhs;
self
}
}
// Clippy thinks using `+` in a `Sub` implementation is suspicious.
#[cfg_attr(feature = "cargo-clippy", allow(suspicious_arithmetic_impl))]
impl<'a> ops::Sub<Fr> for Poly {
type Output = Poly;
fn sub(self, mut rhs: Fr) -> Self::Output {
rhs.negate();
self + rhs
}
}
impl<'a> ops::Sub<u64> for Poly {
type Output = Poly;
fn sub(self, rhs: u64) -> Self::Output {
self - rhs.into_fr()
}
}
// Clippy thinks using any `+` and `-` in a `Mul` implementation is suspicious.
#[cfg_attr(feature = "cargo-clippy", allow(suspicious_arithmetic_impl))]
impl<'a, B: Borrow<Poly>> ops::Mul<B> for &'a Poly {
type Output = Poly;
fn mul(self, rhs: B) -> Self::Output {
let coeff = (0..(self.coeff.len() + rhs.borrow().coeff.len() - 1))
.map(|i| {
let mut c = Fr::zero();
for j in i.saturating_sub(rhs.borrow().degree())..(1 + cmp::min(i, self.degree())) {
let mut s = self.coeff[j];
s.mul_assign(&rhs.borrow().coeff[i - j]);
c.add_assign(&s);
}
c
})
.collect();
Poly { coeff }
}
}
impl<B: Borrow<Poly>> ops::Mul<B> for Poly {
type Output = Poly;
fn mul(self, rhs: B) -> Self::Output {
&self * rhs
}
}
impl<B: Borrow<Self>> ops::MulAssign<B> for Poly {
fn mul_assign(&mut self, rhs: B) {
*self = &*self * rhs;
}
}
impl<'a> ops::Mul<Fr> for Poly {
type Output = Poly;
fn mul(mut self, rhs: Fr) -> Self::Output {
if rhs.is_zero() {
self.coeff.clear();
} else {
self.coeff.iter_mut().for_each(|c| c.mul_assign(&rhs));
}
self
}
}
impl<'a> ops::Mul<u64> for Poly {
type Output = Poly;
fn mul(self, rhs: u64) -> Self::Output {
self * rhs.into_fr()
}
}
impl Drop for Poly {
fn drop(&mut self) {
let start = self.coeff.as_mut_ptr();
unsafe {
for i in 0..self.coeff.len() {
let ptr = start.offset(i as isize);
write_volatile(ptr, Fr::zero());
}
}
}
}
impl Poly {
/// Creates a random polynomial.
pub fn random<R: Rng>(degree: usize, rng: &mut R) -> Self {
Poly {
coeff: (0..(degree + 1)).map(|_| rng.gen()).collect(),
}
}
/// Returns the polynomial with constant value `0`.
pub fn zero() -> Self {
Poly { coeff: Vec::new() }
}
/// Returns the polynomial with constant value `1`.
pub fn one() -> Self {
Self::monomial(0)
}
/// Returns the polynomial with constant value `c`.
pub fn constant(c: Fr) -> Self {
Poly { coeff: vec![c] }
}
/// Returns the identity function, i.e. the polynomial "`x`".
pub fn identity() -> Self {
Self::monomial(1)
}
/// Returns the (monic) monomial "`x.pow(degree)`".
pub fn monomial(degree: usize) -> Self {
Poly {
coeff: iter::repeat(Fr::zero())
.take(degree)
.chain(iter::once(Fr::one()))
.collect(),
}
}
/// Returns the unique polynomial `f` of degree `samples.len() - 1` with the given values
/// `(x, f(x))`.
pub fn interpolate<T, U, I>(samples_repr: I) -> Self
where
I: IntoIterator<Item = (T, U)>,
T: IntoFr,
U: IntoFr,
{
let convert = |(x, y): (T, U)| (x.into_fr(), y.into_fr());
let samples: Vec<(Fr, Fr)> = samples_repr.into_iter().map(convert).collect();
Self::compute_interpolation(&samples)
}
/// Returns the degree.
pub fn degree(&self) -> usize {
self.coeff.len() - 1
}
/// Returns the value at the point `i`.
pub fn evaluate<T: IntoFr>(&self, i: T) -> Fr {
let mut result = match self.coeff.last() {
None => return Fr::zero(),
Some(c) => *c,
};
let x = i.into_fr();
for c in self.coeff.iter().rev().skip(1) {
result.mul_assign(&x);
result.add_assign(c);
}
result
}
/// Returns the corresponding commitment.
pub fn commitment(&self) -> Commitment {
let to_g1 = |c: &Fr| G1Affine::one().mul(*c);
Commitment {
coeff: self.coeff.iter().map(to_g1).collect(),
}
}
/// Removes all trailing zero coefficients.
fn remove_zeros(&mut self) {
let zeros = self.coeff.iter().rev().take_while(|c| c.is_zero()).count();
let len = self.coeff.len() - zeros;
self.coeff.truncate(len)
}
/// Returns the unique polynomial `f` of degree `samples.len() - 1` with the given values
/// `(x, f(x))`.
fn compute_interpolation(samples: &[(Fr, Fr)]) -> Self {
if samples.is_empty() {
return Poly::zero();
} else if samples.len() == 1 {
return Poly::constant(samples[0].1);
}
// The degree is at least 1 now.
let degree = samples.len() - 1;
// Interpolate all but the last sample.
let prev = Self::compute_interpolation(&samples[..degree]);
let (x, mut y) = samples[degree]; // The last sample.
y.sub_assign(&prev.evaluate(x));
let step = Self::lagrange(x, &samples[..degree]);
prev + step * Self::constant(y)
}
/// Returns the Lagrange base polynomial that is `1` in `p` and `0` in every `samples[i].0`.
fn lagrange(p: Fr, samples: &[(Fr, Fr)]) -> Self {
let mut result = Self::one();
for &(sx, _) in samples {
let mut denom = p;
denom.sub_assign(&sx);
denom = denom.inverse().expect("sample points must be distinct");
result *= (Self::identity() - Self::constant(sx)) * Self::constant(denom);
}
result
}
}
/// A commitment to a univariate polynomial.
#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
pub struct Commitment {
/// The coefficients of the polynomial.
#[serde(with = "super::serde_impl::projective_vec")]
pub(super) coeff: Vec<G1>,
}
impl Hash for Commitment {
fn hash<H: Hasher>(&self, state: &mut H) {
self.coeff.len().hash(state);
for c in &self.coeff {
c.into_affine().into_compressed().as_ref().hash(state);
}
}
}
impl<B: Borrow<Commitment>> ops::AddAssign<B> for Commitment {
fn add_assign(&mut self, rhs: B) {
let len = cmp::max(self.coeff.len(), rhs.borrow().coeff.len());
self.coeff.resize(len, G1::zero());
for (self_c, rhs_c) in self.coeff.iter_mut().zip(&rhs.borrow().coeff) {
self_c.add_assign(rhs_c);
}
self.remove_zeros();
}
}
impl<'a, B: Borrow<Commitment>> ops::Add<B> for &'a Commitment {
type Output = Commitment;
fn add(self, rhs: B) -> Commitment {
(*self).clone() + rhs
}
}
impl<B: Borrow<Commitment>> ops::Add<B> for Commitment {
type Output = Commitment;
fn add(mut self, rhs: B) -> Commitment {
self += rhs;
self
}
}
impl Commitment {
/// Returns the polynomial's degree.
pub fn degree(&self) -> usize {
self.coeff.len() - 1
}
/// Returns the `i`-th public key share.
pub fn evaluate<T: IntoFr>(&self, i: T) -> G1 {
let mut result = match self.coeff.last() {
None => return G1::zero(),
Some(c) => *c,
};
let x = i.into_fr();
for c in self.coeff.iter().rev().skip(1) {
result.mul_assign(x);
result.add_assign(c);
}
result
}
/// Removes all trailing zero coefficients.
fn remove_zeros(&mut self) {
let zeros = self.coeff.iter().rev().take_while(|c| c.is_zero()).count();
let len = self.coeff.len() - zeros;
self.coeff.truncate(len)
}
}
/// A symmetric bivariate polynomial in the prime field.
///
/// This can be used for Verifiable Secret Sharing and Distributed Key Generation. See the module
/// documentation for details.
#[derive(Debug, Clone)]
pub struct BivarPoly {
/// The polynomial's degree in each of the two variables.
degree: usize,
/// The coefficients of the polynomial. Coefficient `(i, j)` for `i <= j` is in position
/// `j * (j + 1) / 2 + i`.
coeff: Vec<Fr>,
}
impl Drop for BivarPoly {
fn drop(&mut self) {
let start = self.coeff.as_mut_ptr();
unsafe {
for i in 0..self.coeff.len() {
let ptr = start.offset(i as isize);
write_volatile(ptr, Fr::zero());
}
}
}
}
impl BivarPoly {
/// Creates a random polynomial.
pub fn random<R: Rng>(degree: usize, rng: &mut R) -> Self {
BivarPoly {
degree,
coeff: (0..coeff_pos(degree + 1, 0)).map(|_| rng.gen()).collect(),
}
}
/// Returns the polynomial's degree: It is the same in both variables.
pub fn degree(&self) -> usize {
self.degree
}
/// Returns the polynomial's value at the point `(x, y)`.
pub fn evaluate<T: IntoFr>(&self, x: T, y: T) -> Fr {
let x_pow = self.powers(x);
let y_pow = self.powers(y);
// TODO: Can we save a few multiplication steps here due to the symmetry?
let mut result = Fr::zero();
for (i, x_pow_i) in x_pow.into_iter().enumerate() {
for (j, y_pow_j) in y_pow.iter().enumerate() {
let mut summand = self.coeff[coeff_pos(i, j)];
summand.mul_assign(&x_pow_i);
summand.mul_assign(y_pow_j);
result.add_assign(&summand);
}
}
result
}
/// Returns the `x`-th row, as a univariate polynomial.
pub fn row<T: IntoFr>(&self, x: T) -> Poly {
let x_pow = self.powers(x);
let coeff: Vec<Fr> = (0..=self.degree)
.map(|i| {
let mut result = Fr::zero();
for (j, x_pow_j) in x_pow.iter().enumerate() {
let mut summand = self.coeff[coeff_pos(i, j)];
summand.mul_assign(x_pow_j);
result.add_assign(&summand);
}
result
})
.collect();
Poly { coeff }
}
/// Returns the corresponding commitment. That information can be shared publicly.
pub fn commitment(&self) -> BivarCommitment {
let to_pub = |c: &Fr| G1Affine::one().mul(*c);
BivarCommitment {
degree: self.degree,
coeff: self.coeff.iter().map(to_pub).collect(),
}
}
/// Returns the `0`-th to `degree`-th power of `x`.
fn powers<T: IntoFr>(&self, x: T) -> Vec<Fr> {
powers(x, self.degree)
}
}
/// A commitment to a symmetric bivariate polynomial.
#[derive(Debug, Clone, Serialize, Deserialize, Eq, PartialEq)]
pub struct BivarCommitment {
/// The polynomial's degree in each of the two variables.
degree: usize,
/// The commitments to the coefficients.
#[serde(with = "super::serde_impl::projective_vec")]
coeff: Vec<G1>,
}
impl Hash for BivarCommitment {
fn hash<H: Hasher>(&self, state: &mut H) {
self.degree.hash(state);
for c in &self.coeff {
c.into_affine().into_compressed().as_ref().hash(state);
}
}
}
impl BivarCommitment {
/// Returns the polynomial's degree: It is the same in both variables.
pub fn degree(&self) -> usize {
self.degree
}
/// Returns the commitment's value at the point `(x, y)`.
pub fn evaluate<T: IntoFr>(&self, x: T, y: T) -> G1 {
let x_pow = self.powers(x);
let y_pow = self.powers(y);
// TODO: Can we save a few multiplication steps here due to the symmetry?
let mut result = G1::zero();
for (i, x_pow_i) in x_pow.into_iter().enumerate() {
for (j, y_pow_j) in y_pow.iter().enumerate() {
let mut summand = self.coeff[coeff_pos(i, j)];
summand.mul_assign(x_pow_i);
summand.mul_assign(*y_pow_j);
result.add_assign(&summand);
}
}
result
}
/// Returns the `x`-th row, as a commitment to a univariate polynomial.
pub fn row<T: IntoFr>(&self, x: T) -> Commitment {
let x_pow = self.powers(x);
let coeff: Vec<G1> = (0..=self.degree)
.map(|i| {
let mut result = G1::zero();
for (j, x_pow_j) in x_pow.iter().enumerate() {
let mut summand = self.coeff[coeff_pos(i, j)];
summand.mul_assign(*x_pow_j);
result.add_assign(&summand);
}
result
})
.collect();
Commitment { coeff }
}
/// Returns the `0`-th to `degree`-th power of `x`.
fn powers<T: IntoFr>(&self, x: T) -> Vec<Fr> {
powers(x, self.degree)
}
}
/// Returns the `0`-th to `degree`-th power of `x`.
fn powers<T: IntoFr>(into_x: T, degree: usize) -> Vec<Fr> {
let x = into_x.into_fr();
let mut x_pow_i = Fr::one();
iter::once(x_pow_i)
.chain((0..degree).map(|_| {
x_pow_i.mul_assign(&x);
x_pow_i
}))
.collect()
}
/// Returns the position of coefficient `(i, j)` in the vector describing a symmetric bivariate
/// polynomial.
fn coeff_pos(i: usize, j: usize) -> usize {
// Since the polynomial is symmetric, we can order such that `j >= i`.
if j >= i {
j * (j + 1) / 2 + i
} else {
i * (i + 1) / 2 + j
}
}
#[cfg(test)]
mod tests {
use std::collections::BTreeMap;
use super::{coeff_pos, BivarPoly, IntoFr, Poly};
use pairing::bls12_381::{Fr, G1Affine};
use pairing::{CurveAffine, Field};
use rand;
#[test]
fn test_coeff_pos() {
let mut i = 0;
let mut j = 0;
for n in 0..100 {
assert_eq!(n, coeff_pos(i, j));
if i >= j {
j += 1;
i = 0;
} else {
i += 1;
}
}
}
#[test]
fn poly() {
// The polynomial 5 X³ + X - 2.
let poly = Poly::monomial(3) * 5 + Poly::monomial(1) - 2;
let coeff: Vec<_> = [-2, 1, 0, 5].into_iter().map(IntoFr::into_fr).collect();
assert_eq!(Poly { coeff }, poly);
let samples = vec![(-1, -8), (2, 40), (3, 136), (5, 628)];
for &(x, y) in &samples {
assert_eq!(y.into_fr(), poly.evaluate(x));
}
assert_eq!(Poly::interpolate(samples), poly);
}
#[test]
fn distributed_key_generation() {
let mut rng = rand::thread_rng();
let dealer_num = 3;
let node_num = 5;
let faulty_num = 2;
// For distributed key generation, a number of dealers, only one of who needs to be honest,
// generates random bivariate polynomials and publicly commits to them. In partice, the
// dealers can e.g. be any `faulty_num + 1` nodes.
let bi_polys: Vec<BivarPoly> = (0..dealer_num)
.map(|_| BivarPoly::random(faulty_num, &mut rng))
.collect();
let pub_bi_commits: Vec<_> = bi_polys.iter().map(BivarPoly::commitment).collect();
let mut sec_keys = vec![Fr::zero(); node_num];
// Each dealer sends row `m` to node `m`, where the index starts at `1`. Don't send row `0`
// to anyone! The nodes verify their rows, and send _value_ `s` on to node `s`. They again
// verify the values they received, and collect them.
for (bi_poly, bi_commit) in bi_polys.iter().zip(&pub_bi_commits) {
for m in 1..=node_num {
// Node `m` receives its row and verifies it.
let row_poly = bi_poly.row(m);
let row_commit = bi_commit.row(m);
assert_eq!(row_poly.commitment(), row_commit);
// Node `s` receives the `s`-th value and verifies it.
for s in 1..=node_num {
let val = row_poly.evaluate(s);
let val_g1 = G1Affine::one().mul(val);
assert_eq!(bi_commit.evaluate(m, s), val_g1);
// The node can't verify this directly, but it should have the correct value:
assert_eq!(bi_poly.evaluate(m, s), val);
}
// A cheating dealer who modified the polynomial would be detected.
let wrong_poly = row_poly.clone() + Poly::monomial(2) * Poly::constant(5.into_fr());
assert_ne!(wrong_poly.commitment(), row_commit);
// If `2 * faulty_num + 1` nodes confirm that they received a valid row, then at
// least `faulty_num + 1` honest ones did, and sent the correct values on to node
// `s`. So every node received at least `faulty_num + 1` correct entries of their
// column/row (remember that the bivariate polynomial is symmetric). They can
// reconstruct the full row and in particular value `0` (which no other node knows,
// only the dealer). E.g. let's say nodes `1`, `2` and `4` are honest. Then node
// `m` received three correct entries from that row:
let received: BTreeMap<_, _> = [1, 2, 4]
.iter()
.map(|&i| (i, bi_poly.evaluate(m, i)))
.collect();
let my_row = Poly::interpolate(received);
assert_eq!(bi_poly.evaluate(m, 0), my_row.evaluate(0));
assert_eq!(row_poly, my_row);
// The node sums up all values number `0` it received from the different dealer. No
// dealer and no other node knows the sum in the end.
sec_keys[m - 1].add_assign(&my_row.evaluate(Fr::zero()));
}
}
// Each node now adds up all the first values of the rows it received from the different
// dealers (excluding the dealers where fewer than `2 * faulty_num + 1` nodes confirmed).
// The whole first column never gets added up in practice, because nobody has all the
// information. We do it anyway here; entry `0` is the secret key that is not known to
// anyone, neither a dealer, nor a node:
let mut sec_key_set = Poly::zero();
for bi_poly in &bi_polys {
sec_key_set += bi_poly.row(0);
}
for m in 1..=node_num {
assert_eq!(sec_key_set.evaluate(m), sec_keys[m - 1]);
}
// The sum of the first rows of the public commitments is the commitment to the secret key
// set.
let mut sum_commit = Poly::zero().commitment();
for bi_commit in &pub_bi_commits {
sum_commit += bi_commit.row(0);
}
assert_eq!(sum_commit, sec_key_set.commitment());
}
}

20
src/crypto/protobuf_impl.rs
View File

@ -1,20 +0,0 @@
use super::Signature;
use pairing::bls12_381::G2Compressed;
use pairing::{CurveAffine, CurveProjective, EncodedPoint};
impl Signature {
pub fn to_vec(&self) -> Vec<u8> {
let comp = self.0.into_affine().into_compressed();
comp.as_ref().to_vec()
}
pub fn from_bytes(bytes: &[u8]) -> Option<Self> {
let mut comp = G2Compressed::empty();
comp.as_mut().copy_from_slice(bytes);
if let Ok(affine) = comp.into_affine() {
Some(Signature(affine.into_projective()))
} else {
None
}
}
}

184
src/crypto/serde_impl.rs
View File

@ -1,184 +0,0 @@
/// Serialization and deserialization of a group element's compressed representation.
pub mod projective {
use pairing::{CurveAffine, CurveProjective, EncodedPoint};
use serde::de::Error as DeserializeError;
use serde::{Deserialize, Deserializer, Serialize, Serializer};
const ERR_LEN: &str = "wrong length of deserialized group element";
const ERR_CODE: &str = "deserialized bytes don't encode a group element";
pub fn serialize<S, C>(c: &C, s: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
C: CurveProjective,
{
c.into_affine().into_compressed().as_ref().serialize(s)
}
pub fn deserialize<'de, D, C>(d: D) -> Result<C, D::Error>
where
D: Deserializer<'de>,
C: CurveProjective,
{
let bytes = <Vec<u8>>::deserialize(d)?;
if bytes.len() != <C::Affine as CurveAffine>::Compressed::size() {
return Err(D::Error::custom(ERR_LEN));
}
let mut compressed = <C::Affine as CurveAffine>::Compressed::empty();
compressed.as_mut().copy_from_slice(&bytes);
let to_err = |_| D::Error::custom(ERR_CODE);
Ok(compressed.into_affine().map_err(to_err)?.into_projective())
}
}
/// Serialization and deserialization of vectors of projective curve elements.
pub mod projective_vec {
use std::borrow::Borrow;
use std::marker::PhantomData;
use pairing::CurveProjective;
use serde::{Deserialize, Deserializer, Serialize, Serializer};
use super::projective;
/// A wrapper type to facilitate serialization and deserialization of group elements.
struct CurveWrap<C, B>(B, PhantomData<C>);
impl<C, B> CurveWrap<C, B> {
fn new(c: B) -> Self {
CurveWrap(c, PhantomData)
}
}
impl<C: CurveProjective, B: Borrow<C>> Serialize for CurveWrap<C, B> {
fn serialize<S: Serializer>(&self, s: S) -> Result<S::Ok, S::Error> {
projective::serialize(self.0.borrow(), s)
}
}
impl<'de, C: CurveProjective> Deserialize<'de> for CurveWrap<C, C> {
fn deserialize<D: Deserializer<'de>>(d: D) -> Result<Self, D::Error> {
Ok(CurveWrap::new(projective::deserialize(d)?))
}
}
pub fn serialize<S, C>(vec: &[C], s: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
C: CurveProjective,
{
let wrap_vec: Vec<CurveWrap<C, &C>> = vec.iter().map(CurveWrap::new).collect();
wrap_vec.serialize(s)
}
pub fn deserialize<'de, D, C>(d: D) -> Result<Vec<C>, D::Error>
where
D: Deserializer<'de>,
C: CurveProjective,
{
let wrap_vec = <Vec<CurveWrap<C, C>>>::deserialize(d)?;
Ok(wrap_vec.into_iter().map(|CurveWrap(c, _)| c).collect())
}
}
/// Serialization and deserialization of vectors of field elements.
pub mod field_vec {
use std::borrow::Borrow;
use std::marker::PhantomData;
use pairing::{PrimeField, PrimeFieldRepr};
use serde::de::Error as DeserializeError;
use serde::ser::Error as SerializeError;
use serde::{Deserialize, Deserializer, Serialize, Serializer};
/// A wrapper type to facilitate serialization and deserialization of field elements.
pub struct FieldWrap<F, B>(B, PhantomData<F>);
impl<F, B> FieldWrap<F, B> {
pub fn new(f: B) -> Self {
FieldWrap(f, PhantomData)
}
}
impl<F> FieldWrap<F, F> {
pub fn into_inner(self) -> F {
self.0
}
}
impl<F: PrimeField, B: Borrow<F>> Serialize for FieldWrap<F, B> {
fn serialize<S: Serializer>(&self, s: S) -> Result<S::Ok, S::Error> {
let mut bytes = Vec::new();
self.0
.borrow()
.into_repr()
.write_be(&mut bytes)
.map_err(|_| S::Error::custom("failed to write bytes"))?;
bytes.serialize(s)
}
}
impl<'de, F: PrimeField> Deserialize<'de> for FieldWrap<F, F> {
fn deserialize<D: Deserializer<'de>>(d: D) -> Result<Self, D::Error> {
let bytes: Vec<u8> = Deserialize::deserialize(d)?;
let mut repr = F::zero().into_repr();
repr.read_be(&bytes[..])
.map_err(|_| D::Error::custom("failed to write bytes"))?;
Ok(FieldWrap::new(F::from_repr(repr).map_err(|_| {
D::Error::custom("invalid field element representation")
})?))
}
}
pub fn serialize<S, F>(vec: &[F], s: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
F: PrimeField,
{
let wrap_vec: Vec<FieldWrap<F, &F>> = vec.iter().map(FieldWrap::new).collect();
wrap_vec.serialize(s)
}
pub fn deserialize<'de, D, F>(d: D) -> Result<Vec<F>, D::Error>
where
D: Deserializer<'de>,
F: PrimeField,
{
let wrap_vec = <Vec<FieldWrap<F, F>>>::deserialize(d)?;
Ok(wrap_vec.into_iter().map(|FieldWrap(f, _)| f).collect())
}
}
#[cfg(test)]
mod tests {
use bincode;
use pairing::bls12_381::Bls12;
use pairing::Engine;
use rand::{self, Rng};
#[derive(Debug, Serialize, Deserialize)]
pub struct Vecs<E: Engine> {
#[serde(with = "super::projective_vec")]
curve_points: Vec<E::G1>,
#[serde(with = "super::field_vec")]
field_elements: Vec<E::Fr>,
}
impl<E: Engine> PartialEq for Vecs<E> {
fn eq(&self, other: &Self) -> bool {
self.curve_points == other.curve_points && self.field_elements == other.field_elements
}
}
#[test]
fn vecs() {
let mut rng = rand::thread_rng();
let vecs: Vecs<Bls12> = Vecs {
curve_points: rng.gen_iter().take(10).collect(),
field_elements: rng.gen_iter().take(10).collect(),
};
let ser_vecs = bincode::serialize(&vecs).expect("serialize vecs");
let de_vecs = bincode::deserialize(&ser_vecs).expect("deserialize vecs");
assert_eq!(vecs, de_vecs);
}
}

2
src/dynamic_honey_badger/builder.rs
View File

@ -5,11 +5,11 @@ use std::iter::once;
use std::marker::PhantomData;
use std::sync::Arc;
use crypto::{SecretKey, SecretKeySet, SecretKeyShare};
use rand::{self, Rand, Rng};
use serde::{Deserialize, Serialize};
use super::{ChangeState, DynamicHoneyBadger, JoinPlan, Result, Step, VoteCounter};
use crypto::{SecretKey, SecretKeySet, SecretKeyShare};
use honey_badger::HoneyBadger;
use messaging::NetworkInfo;

2
src/dynamic_honey_badger/mod.rs
View File

@ -63,10 +63,10 @@ use std::mem;
use std::sync::Arc;
use bincode;
use crypto::{PublicKey, PublicKeySet, Signature};
use serde::{Deserialize, Serialize};
use self::votes::{SignedVote, VoteCounter};
use crypto::{PublicKey, PublicKeySet, Signature};
use fault_log::{FaultKind, FaultLog};
use honey_badger::{self, HoneyBadger, Message as HbMessage};
use messaging::{self, DistAlgorithm, NetworkInfo, Target};

2
src/dynamic_honey_badger/votes.rs
View File

@ -4,10 +4,10 @@ use std::hash::Hash;
use std::sync::Arc;
use bincode;
use crypto::Signature;
use serde::{Deserialize, Serialize};
use super::{Change, ErrorKind, Result};
use crypto::Signature;
use fault_log::{FaultKind, FaultLog};
use messaging::NetworkInfo;

2
src/honey_badger.rs
View File

@ -33,11 +33,11 @@ use std::sync::Arc;
use bincode;
use failure::{Backtrace, Context, Fail};
use crypto::{Ciphertext, DecryptionShare};
use itertools::Itertools;
use serde::{Deserialize, Serialize};
use common_subset::{self, CommonSubset};
use crypto::{Ciphertext, DecryptionShare};
use fault_log::{Fault, FaultKind, FaultLog};
use messaging::{self, DistAlgorithm, NetworkInfo, Target};

2
src/lib.rs
View File

@ -119,12 +119,12 @@ extern crate ring;
extern crate serde;
#[macro_use]
extern crate serde_derive;
extern crate threshold_crypto as crypto;
pub mod agreement;
pub mod broadcast;
pub mod common_coin;
pub mod common_subset;
pub mod crypto;
pub mod dynamic_honey_badger;
pub mod fault_log;
mod fmt;

3
src/sync_key_gen.rs
View File

@ -52,10 +52,11 @@
//! ```
//! extern crate rand;
//! extern crate hbbft;
//! extern crate threshold_crypto;
//!
//! use std::collections::BTreeMap;
//!
//! use hbbft::crypto::{PublicKey, SecretKey, SignatureShare};
//! use threshold_crypto::{PublicKey, SecretKey, SignatureShare};
//! use hbbft::sync_key_gen::{PartOutcome, SyncKeyGen};
//!
//! // Two out of four shares will suffice to sign or encrypt something.

1
tests/agreement.rs
View File

@ -24,6 +24,7 @@ extern crate rand;
extern crate serde_derive;
#[macro_use]
extern crate rand_derive;
extern crate threshold_crypto as crypto;
mod network;

1
tests/broadcast.rs
View File

@ -11,6 +11,7 @@ extern crate rand;
extern crate serde_derive;
#[macro_use]
extern crate rand_derive;
extern crate threshold_crypto as crypto;
mod network;

1
tests/common_coin.rs
View File

@ -11,6 +11,7 @@ extern crate rand;
extern crate serde_derive;
#[macro_use]
extern crate rand_derive;
extern crate threshold_crypto as crypto;
mod network;

1
tests/common_subset.rs
View File

@ -11,6 +11,7 @@ extern crate rand;
extern crate serde_derive;
#[macro_use]
extern crate rand_derive;
extern crate threshold_crypto as crypto;
mod network;

1
tests/dynamic_honey_badger.rs
View File

@ -12,6 +12,7 @@ extern crate rand;
extern crate serde_derive;
#[macro_use]
extern crate rand_derive;
extern crate threshold_crypto as crypto;
mod network;

1
tests/honey_badger.rs
View File

@ -13,6 +13,7 @@ extern crate rand;
extern crate rand_derive;
#[macro_use]
extern crate serde_derive;
extern crate threshold_crypto as crypto;
mod network;

2
tests/network/mod.rs
View File

@ -3,9 +3,9 @@ use std::fmt::{self, Debug};
use std::mem;
use std::sync::Arc;
use crypto::SecretKeyShare;
use rand::{self, Rng};
use hbbft::crypto::SecretKeyShare;
use hbbft::messaging::{DistAlgorithm, NetworkInfo, Step, Target, TargetedMessage};
/// A node identifier. In the tests, nodes are simply numbered.

1
tests/queueing_honey_badger.rs
View File

@ -12,6 +12,7 @@ extern crate rand;
extern crate serde_derive;
#[macro_use]
extern crate rand_derive;
extern crate threshold_crypto as crypto;
mod network;

4
tests/sync_key_gen.rs
View File

@ -5,10 +5,12 @@ extern crate env_logger;
extern crate hbbft;
extern crate pairing;
extern crate rand;
extern crate threshold_crypto as crypto;
use std::collections::BTreeMap;
use hbbft::crypto::{PublicKey, SecretKey};
use crypto::{PublicKey, SecretKey};
use hbbft::sync_key_gen::{PartOutcome, SyncKeyGen};
fn test_sync_key_gen_with(threshold: usize, node_num: usize) {