|
sl@0
|
1 |
Description of the Intermediate Value Known Answer Test
|
|
sl@0
|
2 |
--------------------------------------------------------
|
|
sl@0
|
3 |
|
|
sl@0
|
4 |
The test encrypts one plaintext with a variable number of rounds.
|
|
sl@0
|
5 |
In ECB encryption mode, the output PTi is the output after the
|
|
sl@0
|
6 |
initial key addition and i rounds (a round ends with a key
|
|
sl@0
|
7 |
addition).
|
|
sl@0
|
8 |
|
|
sl@0
|
9 |
As explained in the documentation, in ECB decryption mode
|
|
sl@0
|
10 |
there are several definitions of a `round' possible. In order
|
|
sl@0
|
11 |
to make visual inspection more intuitive, we output the
|
|
sl@0
|
12 |
intermediate values that correspond with the output of the
|
|
sl@0
|
13 |
encryption mode.
|
|
sl@0
|
14 |
These values might actually not occur in a practical decryption,
|
|
sl@0
|
15 |
especially in an optimised implementation, where various operations
|
|
sl@0
|
16 |
of different rounds are interchanged.
|
|
sl@0
|
17 |
|
|
sl@0
|
18 |
This explains also why the Java and the C code output different
|
|
sl@0
|
19 |
files for this test.
|