2.15 Data Encryption and Authentication
EFR32 has hardware support for AES encryption, decryption and authentication modes. These security operations can be performed
on data in RAM or any data buffer, without further CPU intervention. The key size is 128 bits.
AES modes of operations directly supported by the EFR32 hardware are listed in
Table 2.2 AES Modes of Operation With Hardware
. In addition to these modes, other modes can also be implemented by using combinations of modes. For exam-
ple, the CCM mode can be implemented using the CTR and CBC-MAC modes in combination.
Table 2.2. AES Modes of Operation With Hardware Support
AES Mode
Encryption / Decryption
Authentication
Comment
ECB
Yes
-
Electronic Code Book
CTR
Yes
-
Counter mode
CCM
Yes
Yes
Counter with CBC-MAC
CCM*
Yes
Yes
CCM with encryption-only and
integrity-only capabilities
GCM
Yes
Yes
Galois Counter Mode
CBC
Yes
-
Cipher Block Chaining
CBC-MAC
-
Yes
Cipher Block Chaining, Mes-
sage Authentication Code
CMAC
-
Yes
Cipher-based MAC
CFB
Yes
-
Cipher Feedback
OFB
Yes
-
Output Feedback
The CRYPTO module can operate directly on data buffers provided by the BUFC module. It is also possible to provide data directly
from the embedded Cortex-M4 or via DMA.
A True Random Number Generator (TRNG) module is also included for additional security. The TRNG is a non-deterministic random
number generator based on a full hardware solution, and is suitable for cryptographic key generation.
Reference Manual
System Overview
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