# `Tezex.Crypto.NaCl`
[🔗](https://github.com/objkt-com/tezex/blob/v4.0.0/lib/crypto/nacl.ex#L1)

NaCl-compatible cryptographic functions for Tezos encrypted key handling.

This module implements the crypto_secretbox_open functionality needed to decrypt
Tezos encrypted private keys that use the NaCl/Sodium encryption standard.

# `crypto_secretbox_open`

```elixir
@spec crypto_secretbox_open(binary(), binary(), binary()) ::
  {:ok, binary()} | {:error, :decryption_failed}
```

Opens (decrypts) a NaCl secretbox using XSalsa20-Poly1305.

## Parameters

- `ciphertext` - The encrypted data (includes auth tag)
- `nonce` - 24-byte nonce (usually zeros for Tezos key encryption)
- `key` - 32-byte encryption key derived from passphrase

## Returns

- `{:ok, plaintext}` - Successfully decrypted data
- `{:error, reason}` - Decryption failed

---

*Consult [api-reference.md](api-reference.md) for complete listing*