The operations supported on BigInts are not constant time. BigInt can be therefore unsuitable for use in cryptography. Many platforms provide native support for cryptography, such as Web Cryptography API or Node.js Crypto.
bigint-mod-arith can be imported to your project with
npm install bigint-mod-arith
Then either require (Node.js CJS):
const bigintModArith = require('bigint-mod-arith')
Node >=10.4 <11.
bigint-mod-arithuses workers to speed up some operations. Workers are enabled by default with Node.js from version 11. In order to use them with Node >=10.4 and <11, you need to execute node with the flag
--experimental-worker, and require the .js file manually (otherwise .cjs is required by default and would not be supported by the workers)const bigintCryptoUtils = require('bigint-crypto-utils/dist/cjs/index.node') // ONLY FOR node >=10.4 <11 !
import * as bigintModArith from 'bigint-mod-arith'
The appropriate version for browser or node is automatically exported.
You can also download the IIFE bundle, the ESM bundle or the UMD bundle and manually add it to your project, or, if you have already imported
bigint-mod-arith to your project, just get the bundles from
An example of usage could be:
/* Stage 3 BigInts with value 666 can be declared as BigInt('666') or the shorter syntax 666n. Notice that you can also pass a number, e.g. BigInt(666), but it is not recommended since values over 2**53 - 1 won't be safe but no warning will be raised. */ const a = BigInt('5') const b = BigInt('2') const n = 19n console.log(bigintModArith.modPow(a, b, n)) // prints 6 console.log(bigintModArith.modInv(2n, 5n)) // prints 3 console.log(bigintModArith.modInv(BigInt('3'), BigInt('5'))) // prints 2