STM32 hardware AES GCM is not working properly

[Nk k]

using the STM32 Crypt processor I could successfully encrypt and decrypt plaintext using AES GCM (STM32 cryptographic library version V1.5.0). The stm contoller that I am using is STM32F479NIHx.

Simultaneously, there is another crypto project in the PC side using the polarssl library (Version polarssl-1.2.15) with the same AES GCM encrypt/decrypt parts. It also working fine.

However, the problem is that when using the same AES256 key, IV array (size 12), plaintext, header (AAD), the STM32F4 and the PC generates different ciphers and tags. Their lengths are the same across the platforms but the content is totally different.So it becomes impossible to encrypt in PC and try to decrypt the cipher in STM32F4.

[Amir NEIFAR]

​Hi Navas,

Thank you for using the cryptolibrary.

We recommend to use the new cryptolib version 3.1.0 which is NIST certified.

Please find the below link to download it.

https://www.st.com/en/embedded-software/x-cube-cryptolib.html

Regards,

Amir

[Nk k]

Thanks Amir

[Amir NEIFAR]

​Hi Navas,

Could you please update if you success to use the cryptolibrary?

Regards,

Amir

[Amir NEIFAR]

​Hi Navas,

Could you please update if you success to use the cryptolibrary?

Regards,

Amir

[Nk k]

Hi Amir,

I didn't check AES GCM with recommended new library . In our case we have no option to use new library in our project. What is the real problem in old library?