Struct threshold_crypto::PublicKeySet

pub struct PublicKeySet { /* fields omitted */ }

A public key and an associated set of public key shares.

Methods

impl PublicKeySet

pub fn threshold(&self) -> usize

Returns the threshold t: any set of t + 1 signature shares can be combined into a full signature.

pub fn public_key(&self) -> PublicKey

Returns the public key.

pub fn public_key_share<T: IntoFr>(&self, i: T) -> PublicKeyShare

Returns the i-th public key share.

pub fn combine_signatures<'a, T, I>(&self, shares: I) -> Result<Signature> where
    I: IntoIterator<Item = (T, &'a SignatureShare)>,
    T: IntoFr, 

Combines the shares into a signature that can be verified with the main public key.

The validity of the shares is not checked: If one of them is invalid, the resulting signature also is. Only returns an error if there is a duplicate index or too few shares.

Validity of signature shares should be checked beforehand, or validity of the result afterwards:

let sk_set = SecretKeySet::random(3, &mut rand::thread_rng());
let sk_shares: Vec<_> = (0..6).map(|i| sk_set.secret_key_share(i)).collect();
let pk_set = sk_set.public_keys();
let msg = "Happy birthday! If this is signed, at least four people remembered!";

// Create four signature shares for the message.
let sig_shares: BTreeMap<_, _> = (0..4).map(|i| (i, sk_shares[i].sign(msg))).collect();

// Validate the signature shares.
for (i, sig_share) in &sig_shares {
    assert!(pk_set.public_key_share(*i).verify(sig_share, msg));
}

// Combine them to produce the main signature.
let sig = pk_set.combine_signatures(&sig_shares).expect("not enough shares");

// Validate the main signature. If the shares were valid, this can't fail.
assert!(pk_set.public_key().verify(&sig, msg));

pub fn decrypt<'a, T, I>(&self, shares: I, ct: &Ciphertext) -> Result<Vec<u8>> where
    I: IntoIterator<Item = (T, &'a DecryptionShare)>,
    T: IntoFr, 

Combines the shares to decrypt the ciphertext.

Trait Implementations

impl Clone for PublicKeySet

fn clone(&self) -> PublicKeySet

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Ord for PublicKeySet

fn cmp(&self, other: &PublicKeySet) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl From<Commitment> for PublicKeySet

fn from(commit: Commitment) -> PublicKeySet

Performs the conversion.

impl PartialOrd<PublicKeySet> for PublicKeySet

fn partial_cmp(&self, other: &PublicKeySet) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &PublicKeySet) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &PublicKeySet) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &PublicKeySet) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &PublicKeySet) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl PartialEq<PublicKeySet> for PublicKeySet

fn eq(&self, other: &PublicKeySet) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &PublicKeySet) -> bool

This method tests for !=.

impl Eq for PublicKeySet

impl Debug for PublicKeySet

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Hash for PublicKeySet

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl Serialize for PublicKeySet

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where
    __S: Serializer, 

Serialize this value into the given Serde serializer.

impl<'de> Deserialize<'de> for PublicKeySet

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where
    __D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.