MTRKeypair (moe.platform.ios API)

```
public interface MTRKeypair
```
This protocol is used by the Matter framework to sign messages with a private key and verify signatures with a public key. The Matter framework may call keypair methods from arbitrary threads and concurrently. Implementations of the keypair methods must not call into any Matter framework APIs.

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`@NotNull SecKeyRef`	`publicKey()`	Return public key for the keypair.
`default @NotNull NSData`	`signMessageECDSA_DER(@NotNull NSData message)`	A function to sign a message using ECDSA
`default @NotNull NSData`	`signMessageECDSA_RAW(@NotNull NSData message)`	A function to sign a message using ECDSA

- Method Detail
  - publicKey
```
@NotNull
@NotNull SecKeyRef publicKey()
```
    Return public key for the keypair.
  - signMessageECDSA_DER
```
@NotNull
default @NotNull NSData signMessageECDSA_DER(@NotNull
                                             @NotNull NSData message)
```
    A function to sign a message using ECDSA
    
    Parameters:
    
    message - Message that needs to be signed
    
    Returns:
    
    An ASN.1 DER-encoded signature (per X9.62). Either this selector or signMessageECDSA_RAW must be supported by a MTRKeypair.
  - signMessageECDSA_RAW
```
@NotNull
default @NotNull NSData signMessageECDSA_RAW(@NotNull
                                             @NotNull NSData message)
```
    A function to sign a message using ECDSA
    
    Parameters:
    
    message - Message that needs to be signed
    
    Returns:
    
    A signature that consists of: 2 EC elements (r and s), in raw point form (see SEC1). Sometimes also called RFC 4754 form or P1363 form. Either this selector or signMessageECDSA_DER must be supported by a MTRKeypair.