Plain text Processing
- Set CTRLB.NEWMSG for the new set of plain text processing.
- Load CIPLEN reg.
- Load (J0+1) in INTVECTx register.
- As described in NIST documentation J 0
= IV || 0 31 || 1 when len(IV)=96 and J0 =GHASHH (IV || 0 s+64 || [len(IV)] 64 ) (s is the minimum
numer of zeroes that should be padded with the Initialization Vector to make it a
multiple of 128) if len(IV) != 96.
- Load plain text in DATA register.
- Set CTRLB.START as 1.
- Wait for INTFLAG.ENCCMP to be set.
- AES Hardware generates output in DATA
register.
- Intermediate GHASH is stored in GHASHx register and Cipher Text available in DATA register.
- Continue 3 to 6 till the input of plain text to get the cipher text and the Hash keys.
- At the last input, set CTRLB.EOM.
- Write last indata to DATA reg.
- Set CTRLB.START as 1.
- Wait for INTFLAG.ENCCMP to be set.
- AES Hardware generates output in DATA register and final Hash key in GHASHx register.
- Load [LEN(A)]64||[LEN(C)]64 in DATA register and set CTRLB.GFMUL and CTRLB.START as 1.
- Wait for INTFLAG.GFMCMP to be set.
- AES Hardware generates final GHASH
value in GHASHx register.