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Bls.getPublicKey

Computes the BLS12-381 public key from a provided private key.

Public Keys can be derived as a point on one of the BLS12-381 groups:

  • G1 Point (Default): - short (48 bytes) - computes longer G2 Signatures (96 bytes) - G2 Point: - long (96 bytes) - computes short G1 Signatures (48 bytes)

Imports

Named
import { Bls } from 'ox'

Examples

Short G1 Public Keys (Default)

import { Bls } from 'ox'
 
const 
const publicKey: {
    x: bigint;
    y: bigint;
    z: bigint;
}
publicKey = Bls.getPublicKey({ privateKey: '0x...' })

Long G2 Public Keys

A G2 Public Key can be derived as a G2 point (96 bytes) using size: 'long-key:short-sig'.

This will allow you to compute G1 Signatures (48 bytes) with Bls.sign.

import { Bls } from 'ox'
 
const publicKey = Bls.getPublicKey({
  privateKey: '0x...',
  size: 'long-key:short-sig',
})
 

const publicKey: {
    x: {
        c0: bigint;
        c1: bigint;
    };
    y: {
        c0: bigint;
        c1: bigint;
    };
    z: {
        c0: bigint;
        c1: bigint;
    };
}
publicKey

Serializing

Public Keys can be serialized to hex or bytes using BlsPoint.toHex or BlsPoint.toBytes:

import { Bls, BlsPoint } from 'ox'
 
const publicKey = Bls.getPublicKey({ privateKey: '0x...' })
 
const 
const publicKeyHex: BlsPoint.G1Hex
publicKeyHex = BlsPoint.toHex(publicKey)
 
 
const 
const publicKeyBytes: BlsPoint.G1Bytes
publicKeyBytes = BlsPoint.toBytes(publicKey)

They can also be deserialized from hex or bytes using BlsPoint.fromHex or BlsPoint.fromBytes:

import { Bls, BlsPoint } from 'ox'
 
const publicKeyHex = '0x...'
 
const 
const publicKey: {
    x: bigint;
    y: bigint;
    z: bigint;
}
publicKey = BlsPoint.fromHex(publicKeyHex, 'G1')

Definition

function getPublicKey<size>(
  options: getPublicKey.Options<size>,
): size extends 'short-key:long-sig' ? BlsPoint.G1 : BlsPoint.G2

Source: src/core/Bls.ts

Parameters

options

  • Type: getPublicKey.Options<size>

The options to compute the public key.

options.privateKey

  • Type: 0x${string} | Uint8Array

Private key to compute the public key from.

options.size

  • Type: size | Size
  • Optional

Size of the public key to compute.

  • 'short-key:long-sig': 48 bytes; computes long signatures (96 bytes)
  • 'long-key:short-sig': 96 bytes; computes short signatures (48 bytes)

Return Type

The computed public key.

size extends 'short-key:long-sig' ? BlsPoint.G1 : BlsPoint.G2