Bls

Utility functions for BLS12-381 cryptography.

Examples

Below are some examples demonstrating common usages of the Bls module:

Computing a Random Private Key

A random private key can be computed using Bls.randomPrivateKey:

import { Bls } from 'ox'
 
const privateKey = Bls.randomPrivateKey()
'0x...'

Getting a Public Key

A public key can be derived from a private key using Bls.getPublicKey:

import { Bls } from 'ox'
 
const privateKey = Bls.randomPrivateKey()
const publicKey = Bls.getPublicKey({ privateKey })
{ x: 3251...5152n, y: 1251...5152n, z: 1n }

Signing a Payload

A payload can be signed using Bls.sign:

import { Bls } from 'ox'
 
const privateKey = Bls.randomPrivateKey()
const signature = Bls.sign({ payload: '0xdeadbeef', privateKey })
{ x: 1251...5152n, y: 1251...5152n, z: 1n }

Verifying a Signature

A signature can be verified using Secp256k1.verify:

import { Bls } from 'ox'
 
const privateKey = Bls.randomPrivateKey()
const publicKey = Bls.getPublicKey({ privateKey })
const signature = Bls.sign({ payload: '0xdeadbeef', privateKey })
 
const isValid = Bls.verify({ 
  payload: '0xdeadbeef', 
  publicKey, 
  signature, 
})
true

Aggregating Public Keys & Signatures

Public keys and signatures can be aggregated using Bls.aggregate:

import { Bls } from 'ox'
 
const publicKeys = [
  Bls.getPublicKey({ privateKey: '0x...' }),
  Bls.getPublicKey({ privateKey: '0x...' }),
]
const publicKey = Bls.aggregate(publicKeys)
 
const signatures = [
  Bls.sign({ payload: '0x...', privateKey: '0x...' }),
  Bls.sign({ payload: '0x...', privateKey: '0x...' }),
]
const signature = Bls.aggregate(signatures)

Verify Aggregated Signatures

We can also pass a public key and signature that was aggregated with Bls.aggregate to Bls.verify.

import { Bls, Hex } from 'ox'
 
const payload = Hex.random(32)
const privateKeys = Array.from({ length: 100 }, () => Bls.randomPrivateKey())
 
const publicKeys = privateKeys.map((privateKey) =>
  Bls.getPublicKey({ privateKey }),
)
const signatures = privateKeys.map((privateKey) =>
  Bls.sign({ payload, privateKey }),
)
 
const publicKey = Bls.aggregate(publicKeys)
const signature = Bls.aggregate(signatures)
 
const valid = Bls.verify({ payload, publicKey, signature })

Functions

Name	Description
`Bls.aggregate`	Aggregates a set of BLS points that are either on the G1 or G2 curves (ie. public keys or signatures).
`Bls.getPublicKey`	Computes the BLS12-381 public key from a provided private key.
`Bls.randomPrivateKey`	Generates a random BLS12-381 private key.
`Bls.sign`	Signs the payload with the provided private key.
`Bls.verify`	Verifies a payload was signed by the provided public key(s).

Types

Name	Description
`Bls.Size`