Struct KeyShares 

pub struct KeyShares {
    pub points: Vec<PointInFiniteField>,
    pub threshold: usize,
    pub integrity: String,
}

Shamir’s Secret Sharing for PrivateKey backup and recovery.

Splits a private key into total shares such that any threshold shares can reconstruct the original key, but fewer shares reveal nothing about the secret.

Share format (backup string): “base58(x).base58(y).threshold.integrity” where integrity is the first 8 hex chars of hash160(pubkey) as hex.

Fields

points: Vec<PointInFiniteField>

threshold: usize

integrity: String

Implementations

impl KeyShares

pub fn new( points: Vec<PointInFiniteField>, threshold: usize, integrity: String, ) -> Self

Create a new KeyShares instance.

pub fn split( key: &PrivateKey, threshold: usize, total: usize, ) -> Result<Self, PrimitivesError>

Split a private key into shares using Shamir’s Secret Sharing.

Arguments

• key - The private key to split
• threshold - Minimum shares needed to reconstruct (must be >= 2)
• total - Total shares to generate (must be >= threshold)

Returns

A KeyShares instance containing the shares, threshold, and integrity hash.

pub fn to_backup_format(&self) -> Vec<String>

Convert shares to backup format strings.

Each share is formatted as: “base58(x).base58(y).threshold.integrity”

pub fn from_backup_format(shares: &[String]) -> Result<Self, PrimitivesError>

Parse shares from backup format strings.

Each share must be in format: “base58(x).base58(y).threshold.integrity”

pub fn reconstruct(shares: &KeyShares) -> Result<PrivateKey, PrimitivesError>

Reconstruct a private key from shares.

Requires at least threshold shares. Uses Lagrange interpolation to recover the secret (polynomial value at x=0).

Arguments

• shares - The KeyShares containing points, threshold, and integrity hash

Returns

The reconstructed PrivateKey, validated against the integrity hash.