Skip to main content
generatePrimeSync - crypto - Node documentation
function generatePrimeSync

Usage in Deno

import { generatePrimeSync } from "node:crypto";
generatePrimeSync(size: number): ArrayBuffer

Generates a pseudorandom prime of size bits.

If options.safe is true, the prime will be a safe prime -- that is, (prime - 1) / 2 will also be a prime.

The options.add and options.rem parameters can be used to enforce additional requirements, e.g., for Diffie-Hellman:

  • If options.add and options.rem are both set, the prime will satisfy the condition that prime % add = rem.
  • If only options.add is set and options.safe is not true, the prime will satisfy the condition that prime % add = 1.
  • If only options.add is set and options.safe is set to true, the prime will instead satisfy the condition that prime % add = 3. This is necessary because prime % add = 1 for options.add > 2 would contradict the condition enforced by options.safe.
  • options.rem is ignored if options.add is not given.

Both options.add and options.rem must be encoded as big-endian sequences if given as an ArrayBuffer, SharedArrayBuffer, TypedArray, Buffer, or DataView.

By default, the prime is encoded as a big-endian sequence of octets in an ArrayBuffer. If the bigint option is true, then a bigint is provided.

Parameters

size: number

The size (in bits) of the prime to generate.

Return Type

ArrayBuffer
generatePrimeSync(
size: number,
): bigint

Parameters

size: number

Return Type

bigint
generatePrimeSync(
size: number,
): ArrayBuffer

Parameters

size: number

Return Type

ArrayBuffer
generatePrimeSync(
size: number,
): ArrayBuffer | bigint

Parameters

size: number

Return Type

ArrayBuffer | bigint