Hardware ECB decryption(AES)

[Challen Wong]

Hi,

     I want to use hardware ECB encryption and decryption in 52840.I had tested the demo from nRF5_SDK_13.1.0\examples\crypto\nrf_cc310\aes\pca10056 . However,i can't find the way to to decrypt.Is there any function to use the Hardware ECB decryption.

Thanks and best regards

[Jakub Rzeszutko]

Hi,

Decryption is similar to encryption. The only difference is in the init function SaSi_AesInit. You need to change its second argument to: SASI_AES_DECRYPT. Other steps are the same as for encryption

[Martin Lesund]

Hi Challen,

  The example you are referring to is only using encryption, but you can use the same API for the decryption.  The first parameter to CRYS_AESCCM chooses if it's gonna be encryption or decryption. (SASI_AES_ENCRYPT can be changed to SASI_AES_DECRYPT, both from the enum SaSiAesEncryptMode_t)

You would presumably find what you need if you look in the API-Documentation to CC_AESCCM found in [<SDK_Version>\external\nrf_cc310\include\crys_aesccm.h] 

(Note: CRYS_AESCCM which is used in the example is defined to CC_AESCCM in crys_aesccm.h)

Best Regards,

Martin L.