Crypto cant sign/verify prehashed inputs

Why this is a good first issue

The issue involves unclear expectations around prehashed inputs in crypto.sign/verify.

AI Summary

The issue revolves around the expectation that passing null as the algorithm parameter in crypto.sign/verify should treat the input as prehashed (raw). This behavior is not documented, making it a feature request rather than a bug. The implementation may require changes to OpenSSL primitives and careful consideration of behavioral expectations.

Issue Description

Version

Node.js v22.20.0 - Node.js v24.10.0

Platform

all

Subsystem

crypto

What steps will reproduce the bug?

const crypto = require('crypto');

const message		 	= Buffer.from('LmM8PqCO1QIpTse0s+MQEJ7YXOSZuqyjPCJ4tIZ+OrU=', 'base64'),
			prehash 	 	= crypto.createHash('sha256').update(message).digest();

const namedCurve 	= 'secp256k1',
			keyPair 	 	= crypto.generateKeyPairSync('ec', { namedCurve }),
			signature		= crypto.sign(null, prehash, {
											key					: keyPair.privateKey,
											dsaEncoding	: 'ieee-p1363'
										});

console.log(crypto.verify(null, message, {
	key					: keyPair.publicKey,
	dsaEncoding	: 'ieee-p1363'
}, signature), ' message internal-internal (must be false)');

console.log(crypto.verify(null, prehash, {
	key					: keyPair.publicKey,
	dsaEncoding	: 'ieee-p1363'
}, signature), ' prehash internal-internal (must be true)');

// Simple unitary test:
const PUBLIC_KEY_PEM = '-----BEGIN PUBLIC KEY-----\n' +
										 	'MFYwEAYHKoZIzj0CAQYFK4EEAAoDQgAE6Yvel06IICYJZ/XsuPEFTpDt0aU8dwLK\n' +
										 	'jvgxyYTeZ/vlS49/PDRIr5JDz+QNWFB9ZM9tf4i9SdT0LVtlgRj3dQ==\n' +
										 	'-----END PUBLIC KEY-----',
			publicKey 		 = crypto.createPublicKey(PUBLIC_KEY_PEM),
			signOfPreHash  = Buffer.from('Djv4wD3eWu8lHI3DrN2Dypdrirj+J1rfJD5O1B/Tw8sYy38jms77neECQ0S9LHpnWun+Jb9iOZNbYjH+CoVUnA==', 'base64');

console.log('== BUG HERE ==');

console.log(crypto.verify(null, message, {
	key					: publicKey,
	dsaEncoding	: 'ieee-p1363'
}, signOfPreHash), ' message external-internal (must be false)');

console.log(crypto.verify(null, prehash, {
	key					: publicKey,
	dsaEncoding	: 'ieee-p1363'
}, signOfPreHash), ' prehash external-internal (must be true)');

How often does it reproduce? Is there a required condition?

No precondition required.

What is the expected behavior? Why is that the expected behavior?

When send null to algorithm param i expect that message payload be raw, prehashed, dont want an addit

GitHub Labels

cryptofeature request