AES132 using basic Encrypt/Decrypt command for external data

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I tried using AES132 in Legacy mode. I am using ACES studio and chip is not locked. Legacy mode enabled in config registers.

The legacy mode works fine. But later found out that the encryption is possible, but nothing has been mentioned about decryption in legacy mode.

 

Now i am trying to use the aes132 by using encrypt and decrypt command.

Settings:

The chip is still in unlocked state.

The key 03 is directly written via ACES studio GUI.

The key configuration is written: E9 50 00 01

Everything is left default.

I used command builder to send Encrypt command with following parameters.

19 06 00 00 03 00 10 74 68 69 73 5F 69 73 5F 74 65 73 74 64 61 74 61 1F 8E

(19- total bytes 25, 06 - opcode, 00- mode, 00 03 - 3rd key, 00 10 - 16 bytes will be encrypted, 16 bytes random data, CRC1, CRC2)

The output should be: Encrypted data and OUTMAC.

However, i am getting response:  04 20 18 C0 ( ERR and RRDY bit set in status register).

Snapshot is attached, showing key, command builder, log window, status register.

 

Q1: Is it necessary to lock the CHIP before using these Encrypt/Decrypt command?

Q2: What is wrong in above steps, because response is showing error?

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Total votes: 0

 

Q1 The chip does not need to be locked to use these commands.

 

Q2. Return code 0x20 indicates a nonce error. Have you loaded a valid nonce? Key config E9 50 00 01 does not force a random nonce, but you must load something for the nonce.

 

 

Last Edited: Thu. May 10, 2018 - 10:50 PM