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# ChaChaPoly

An implementation of the ChaCha20-Poly1305 cipher.

```
enum ChaChaPoly
```

## Topics

### Storing the output

[`ChaChaPoly.SealedBox`](/documentation/CryptoKit/ChaChaPoly/SealedBox)

A secure container for your data that you access using a cipher.

### Getting a nonce

[`ChaChaPoly.Nonce`](/documentation/CryptoKit/ChaChaPoly/Nonce)

A value used once during a cryptographic operation and then discarded.

### Securing the plaintext message

[`seal(_:using:nonce:)`](/documentation/CryptoKit/ChaChaPoly/seal(_:using:nonce:))

Secures the given plaintext message with encryption and an
authentication tag.

[`seal(_:using:nonce:authenticating:)`](/documentation/CryptoKit/ChaChaPoly/seal(_:using:nonce:authenticating:))

Secures the given plaintext message with encryption and an
authentication tag that covers both the encrypted data and additional
data.

### Decrypting and verifying the message

[`open(_:using:)`](/documentation/CryptoKit/ChaChaPoly/open(_:using:))

Decrypts the message and verifies its authenticity.

[`open(_:using:authenticating:)`](/documentation/CryptoKit/ChaChaPoly/open(_:using:authenticating:))

Decrypts the message and verifies the authenticity of both the encrypted
message and additional data.


---

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