brp_Desfire_ChangeExtKey()

brp_errcode brp_Desfire_ChangeExtKey	(	brp_protocol	protocol,
		brp_Desfire_ChangeExtKey_MasterKeyType	MasterKeyType,
		bool	IsKeySet,
		bool	IsAesKey,
		bool	IsVersion,
		bool	IsChangeKey,
		unsigned	KeyNo,
		unsigned	KeyVersion,
		brp_buf	NewKey,
		size_t	NewKey_len,
		brp_buf	OldKey,
		size_t	OldKey_len,
		unsigned	KeySet
	)

This command allows to change any key stored on the card.

The key length has to be set according to the desired encryption algorithm:

• DES encryption uses keys of 8 Byte.
• 3DES and AES encryption uses keys of 16 Byte.
• 3K3DES encryption uses keys of 24 Byte.

Parameters

[in]	protocol	used to execute the command
[in]	MasterKeyType	These bits must only be set if the card's Master Key is changed. They specify the type of the new card's Master Key.
[in]	IsKeySet	Only needed for Desfire EV2 with multiple Keysets. If true ,the reader executes the Desfire "ChangeKeyEV2" command instead of the Desfire "ChangeKey" command.
[in]	IsAesKey	Has to be set if the new key is an AES key.
[in]	IsVersion	Has to be set if the NewKeyVersion parameter is present.
[in]	IsChangeKey	Has to be set if the key used to authenticate the card is the key that needs to be changed (as specified in KeyNo). In this case, the parameter OldKey has to be omitted.
[in]	KeyNo	Number of key (0-13) to modify. Has to be 0 if the application Master Key is changed.
[in]	KeyVersion	Version of the new key. Remarks: * If this value is not available (i.e. if IsVersion is not set), 0 will be assumed as NewKeyVersion.
[in]	NewKey	New key (16 bytes).
[in]	NewKey_len
[in]	OldKey	Current key (16 bytes).
[in]	OldKey_len
[in]	KeySet	specifies KeySet needed for multiple keysets (EV2 extension).