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Slicing and dicing
Appendix B of draft -04 of the resolution document says
The key for DES-CBC is derived from the first eight (8) non-weak and
non-semi-weak (see Appendix A) bytes of SKEYID_e.
If the bytes 1-8 are a weak or semi-weak key, do we then go on to
bytes 2-9 (I hope not!) or bytes 9-16?
The same appendix later says
The key for 3DES-CBC is the first twenty-four (24) bytes of a key
derived in the aforementioned pseudo-random function feedback method.
3DES-CBC is an encrypt-decrypt-encrypt operation using the first,
middle, and last eight (8) bytes of the entire 3DES-CBC key.
This means that no weak key test may be done for 3DES-CBC. Was this
the intent?
--
Karl Fox, servant of God, employee of Ascend Communications
655 Metro Place South, Suite 370, Dublin, Ohio 43017 +1 614 760 4041
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