crypto: add generatePrime/checkPrime

[jasnell]

APIs for generating and checking pseudo-random primes.

Scratching an itch here. For a set of crypto benchmarks that I've been running I've needed the ability to generate prime test vectors but always had to rely on an external module. Which is silly since openssl has this built in and quite easy to expose.

One of the use cases is to generate primes for diffie hellman with a bit more control over the generation parameters.

crypto.generatePrime(32, {
  safe: true,
  add: 12n,
  rem: 11n,
}, (err, prime) => {
  const dh = crypto.createDiffieHellman(prime);
});

The crypto.checkPrime() does exactly what its name suggest... verifies that an input is a prime within a reasonable margin of error.

Signed-off-by: James M Snell [email protected]

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/35636/ 💚

[panva]

cc @nodejs/crypto

[jasnell]

The PR has been updated to split checkPrime() into sync and async variants. The check prime operation can take a while based on the size of the prime candidate and the number of checks so moving that off loop makes the most sense.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/35684/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/35685/ 💚

[tniessen]

Using ArrayBuffer as the primary representation of prime numbers might be WebCrypto-ish, but it doesn't feel JavaScript-ish or Node.js-ish to me. Both OpenSSL and JavaScript have a BigInt/BIGNUM type, and I don't think our new APIs should steer away from that fact. While static representations of keys typically encode numbers as byte sequences, programmers should have access to types with better semantics. (Sure, higher-level types don't provide memory safety etc., but... it's JavaScript.)

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/35709/ 💚

[jasnell]

Update: I've renamed the function to generatePrime()/generatePrimeSync() to avoid some name bikeshedding debates later on

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/35736/ 💚

[tniessen]

LGTM. I think it's great to support BigInt, and I understand the hesitation to use BigInt as the default output format even though I personally believe it would be a better fit. rem and add likely don't need to be in secure memory, but they are short-lived, so it doesn't matter much.

[jasnell]

Landed in bb13469