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MPC5777C CSE Miyaguchi-Preneel Compression CMD

Question asked by Ellen Wang on Jun 16, 2017
Latest reply on Jun 26, 2017 by Ellen Wang

For the MP compression, does the input compress data length have to be  multiple of 128 bits? I didn't see this requirement on MPC5777C reference manual.

the "SHE_Funtional_Spec_V_1.1.pdf" 3.3 mentioned messages have to be preprocessed into 128 bit chunks  before feeding them to the compression algorithm. Does it handle by hardware, don't need we manually padded and parsed into 128 bit chucks, right?

 

I try compress 128bits, 160 bit, 256 bits, but none of that success, CSE_SR all return 0x15 (length error)

 

Another question is about

K1= KDF( KEYauthID, KEY_UPDATE_ENC_C ): AES-MP( KEYauthID | KEY_UPDATE_ENC_C)

if I use the MASTER_ECU_KEY, then the KEYauthID will be 0x1, I transfer it to an long word, and concatenation with 128 bits KEY_UPDATE_ENC_C, so the length is 160 bits, all the pass in address(length address, start address, output address) are aligned on 32 bit. but I still get  0x15 (length error)

 

In above Two cases, I don't know what part I didn't do it right, why always get 0x15 (length error).

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