Gets the block length associated with a cryptographic key.


func SecKeyGetBlockSize(_ key: SecKey) -> Int



The key for which you want the block length.

Return Value

The block length associated with the key in bytes. If the key is an RSA key, for example, this is the size of the modulus.

See Also

Examining Keys

func SecKeyIsAlgorithmSupported(SecKey, SecKeyOperationType, SecKeyAlgorithm) -> Bool

Returns a Boolean indicating whether a key is suitable for an operation using a certain algorithm.

func SecKeyCopyAttributes(SecKey) -> CFDictionary?

Gets the attributes of a given key.

struct SecKeyAlgorithm

The algorithms that cryptographic keys enable.

enum SecKeyOperationType

The types of operations that you can use a cryptographic key to perform.

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