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# kSecOAEPMessageLengthAttributeName

The OAEP message length.

```
let kSecOAEPMessageLengthAttributeName: CFString
```

## Discussion

Optionally set the value to a <doc://com.apple.documentation/documentation/CoreFoundation/CFNumber> indicating a specific message size when the [`kSecPaddingKey`](/documentation/Security/kSecPaddingKey) attribute is set to [`kSecPaddingOAEPKey`](/documentation/Security/kSecPaddingOAEPKey). If you don’t set this attribute, the minimum padding is used by default.

This attribute is ignored when padding is not set to OAEP.

---

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