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  "title" : "HPKE.KDF"
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# HPKE.KDF

The key derivation functions to use in HPKE.

```
enum KDF
```

## Topics

### Enumeration Cases

[`case HKDF_SHA256`](/documentation/CryptoKit/HPKE/KDF/HKDF_SHA256)

An HMAC-based key derivation function that uses SHA-2 hashing with a 256-bit digest.

[`case HKDF_SHA384`](/documentation/CryptoKit/HPKE/KDF/HKDF_SHA384)

An HMAC-based key derivation function that uses SHA-2 hashing with a 384-bit digest.

[`case HKDF_SHA512`](/documentation/CryptoKit/HPKE/KDF/HKDF_SHA512)

An HMAC-based key derivation function that uses SHA-2 hashing with a 512-bit digest.

## Relationships

### Conforms To

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Equatable`](/documentation/Swift/Equatable)

[`Hashable`](/documentation/Swift/Hashable)

[`CaseIterable`](/documentation/Swift/CaseIterable)

[`Sendable`](/documentation/Swift/Sendable)

---

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