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# LAPrivateKey

The private portion of an asymmetric key pair.

```
class LAPrivateKey
```

## Topics

### Accessing the associated public key

[`publicKey`](/documentation/LocalAuthentication/LAPrivateKey/publicKey)

The public key that corresponds with the private key in a key pair.

### Checking algorithm support

[`canDecrypt(using:)`](/documentation/LocalAuthentication/LAPrivateKey/canDecrypt(using:))

Checks whether the algorithm you supply is valid for decrypting data with the key.

[`canExchangeKeys(using:)`](/documentation/LocalAuthentication/LAPrivateKey/canExchangeKeys(using:))

Checks whether the algorithm you supply is valid for performing key exchanges.

[`canSign(using:)`](/documentation/LocalAuthentication/LAPrivateKey/canSign(using:))

Checks whether the algorithm you supply is valid for signing data with the key.

### Performing cryptographic operations

[`decrypt(_:algorithm:completion:)`](/documentation/LocalAuthentication/LAPrivateKey/decrypt(_:algorithm:completion:))

Decrypts the data you supply with a given algorithm.

[`exchangeKeys(publicKey:algorithm:parameters:completion:)`](/documentation/LocalAuthentication/LAPrivateKey/exchangeKeys(publicKey:algorithm:parameters:completion:))

Performs a Diffie-Hellman style key exchange operation.

[`sign(_:algorithm:completion:)`](/documentation/LocalAuthentication/LAPrivateKey/sign(_:algorithm:completion:))

Generates a digital signature for the data you supply.


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