class DiffieHellman
Usage in Deno
```typescript import { DiffieHellman } from "node:node__crypto.d.ts"; ```The `DiffieHellman` class is a utility for creating Diffie-Hellman key
exchanges.
Instances of the `DiffieHellman` class can be created using the [createDiffieHellman](../.././node__crypto.d.ts/~/createDiffieHellman) function.
```js
import assert from 'node:assert';
const {
createDiffieHellman,
} = await import('node:crypto');
// Generate Alice's keys...
const alice = createDiffieHellman(2048);
const aliceKey = alice.generateKeys();
// Generate Bob's keys...
const bob = createDiffieHellman(alice.getPrime(), alice.getGenerator());
const bobKey = bob.generateKeys();
// Exchange and generate the secret...
const aliceSecret = alice.computeSecret(bobKey);
const bobSecret = bob.computeSecret(aliceKey);
// OK
assert.strictEqual(aliceSecret.toString('hex'), bobSecret.toString('hex'));
```
verifyError: number
A bit field containing any warnings and/or errors resulting from a check
performed during initialization of the `DiffieHellman` object.
The following values are valid for this property (as defined in `node:constants` module):
* `DH_CHECK_P_NOT_SAFE_PRIME`
* `DH_CHECK_P_NOT_PRIME`
* `DH_UNABLE_TO_CHECK_GENERATOR`
* `DH_NOT_SUITABLE_GENERATOR`
computeSecret(otherPublicKey: ArrayBufferView,inputEncoding?: null,outputEncoding?: null,): Buffer
Computes the shared secret using `otherPublicKey` as the other
party's public key and returns the computed shared secret. The supplied
key is interpreted using the specified `inputEncoding`, and secret is
encoded using specified `outputEncoding`.
If the `inputEncoding` is not
provided, `otherPublicKey` is expected to be a `Buffer`, `TypedArray`, or `DataView`.
If `outputEncoding` is given a string is returned; otherwise, a `Buffer` is returned.
computeSecret(): Buffer
computeSecret(): string
computeSecret(): string
generateKeys(): Buffer
Generates private and public Diffie-Hellman key values unless they have been
generated or computed already, and returns
the public key in the specified `encoding`. This key should be
transferred to the other party.
If `encoding` is provided a string is returned; otherwise a `Buffer` is returned.
This function is a thin wrapper around [`DH_generate_key()`](https://www.openssl.org/docs/man3.0/man3/DH_generate_key.html). In particular,
once a private key has been generated or set, calling this function only updates
the public key but does not generate a new private key.
generateKeys(encoding: BinaryToTextEncoding): string
getGenerator(): Buffer
Returns the Diffie-Hellman generator in the specified `encoding`.
If `encoding` is provided a string is
returned; otherwise a `Buffer` is returned.
getGenerator(encoding: BinaryToTextEncoding): string
getPrime(): Buffer
Returns the Diffie-Hellman prime in the specified `encoding`.
If `encoding` is provided a string is
returned; otherwise a `Buffer` is returned.
getPrime(encoding: BinaryToTextEncoding): string
getPrivateKey(): Buffer
Returns the Diffie-Hellman private key in the specified `encoding`.
If `encoding` is provided a
string is returned; otherwise a `Buffer` is returned.
getPrivateKey(encoding: BinaryToTextEncoding): string
getPublicKey(): Buffer
Returns the Diffie-Hellman public key in the specified `encoding`.
If `encoding` is provided a
string is returned; otherwise a `Buffer` is returned.
getPublicKey(encoding: BinaryToTextEncoding): string
setPrivateKey(privateKey: ArrayBufferView): void
Sets the Diffie-Hellman private key. If the `encoding` argument is provided,`privateKey` is expected
to be a string. If no `encoding` is provided, `privateKey` is expected
to be a `Buffer`, `TypedArray`, or `DataView`.
This function does not automatically compute the associated public key. Either `diffieHellman.setPublicKey()` or `diffieHellman.generateKeys()` can be
used to manually provide the public key or to automatically derive it.
setPrivateKey(privateKey: string,encoding: BufferEncoding,): void
setPublicKey(publicKey: ArrayBufferView): void
Sets the Diffie-Hellman public key. If the `encoding` argument is provided, `publicKey` is expected
to be a string. If no `encoding` is provided, `publicKey` is expected
to be a `Buffer`, `TypedArray`, or `DataView`.
setPublicKey(publicKey: string,encoding: BufferEncoding,): void