[SOLVED] AES-XCBC-MAC-96 problem

[ahmeddeia]

salam alikom

i am working on AES-XCBC-MAC-96 and when i try case#7 it gives me wrong output although all the previous 6 cases are ok thanks ***
have any one tried this case??

please help me

thanks,

salam alikom

 

[blooz]

salam alikom

i am working on AES-XCBC-MAC-96 and when i try case#7 it gives me wrong output although all the previous 6 cases are ok thanks ***
have any one tried this case??

please help me

thanks,

salam alikom

Since the 7th test vector gives a wrong output ,
possible reasons are
1.Design has some Weakness
generally some iteration procedures are involved in these Message Authentication Codes ,so some parameter may be
wrong that gives the mismatch .

I have implemented a CMAC with Anubis instead of AES ,one method of trouble shooting is generally to check the results produced by
a Well verified implementation .In the case of Anubis there were some troubles and a parallel implementation in C along with HDL Were used to
verify the working .

Cryptography for Developers -Simon Johnson has a good chapter on Message authentication Codes ,it was one of mainstay during the CMAC development

 

[ahmeddeia]

salam alikom

thanks blooz for ur great help, u always help me,...........really thanks

well for the test vectors, i doubt them as they are tested by the author of XCBC-MAC himself: "These test cases were provided by John Black, co-author of the
XCBC-MAC algorithm, who verified them with 2 independent implementations"

well i will try to check them,maybe the error is in my matlab code

thanks blooz

---------- Post added at 12:44 ---------- Previous post was at 10:52 ----------

salam alikom

hi all, i have told u that i had a problem in AES-XCBC-MAC-96 test vectors especially in case#7
well the problem is solved,i had a problem in the input entered to my function,i didn't enter it correctly....that's the whole problem

salam alikom