#6461: [with patch, needs work] Schaefer's Simplified Data Encryption Standard
for
educational purposes
--------------------------+-------------------------------------------------
Reporter: mvngu | Owner: somebody
Type: enhancement | Status: new
Priority: major | Milestone: sage-4.1.1
Component: cryptography | Keywords: cryptography, DES, S-DES
Reviewer: | Author: Minh Van Nguyen
Merged: |
--------------------------+-------------------------------------------------
Comment(by mvngu):
Replying to [comment:2 malb]:
> * I assume that the specification implemented is correct, I didn't
check against the paper, are there official test vectors?
Unfortunately, I don't have access to the original paper by Schaefer, and
neither do my institution. I relied on the note at
http://bitterroot.vancouver.wsu.edu/cs427_Spring09/docs/sdes.pdf
[[BR]]
> * {{{__cmp__}}} expects you to return an integer (-1,0,1) and not
{{{True}}} or {{{False}}}, cf.
http://docs.python.org/reference/datamodel.html
Before switching to using {{{__cmp__()}}}, I used {{{==}}} for comparing
objects. But then doing {{{a == loads(dumps(a))}}} consistently returned
{{{False}}} for me. Let me try it again.
[[BR]]
> * it is a bit confusing that P is often the plaintext (cf. C for
ciphertext) and the permutation, but that might be a problem in the paper
Ah... the notes I referenced above uses {{{IP}}} to denote the initial
permutation and {{{IP^-1}}} for its inverse. Perhaps that is less
confusing you think?
[[BR]]
> * it would be nice to have an {{{sbox(n)}}} function to return the
S-Boxes 0 and 1
That can be done.
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/6461#comment:3>
Sage <http://sagemath.org/>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/sage-trac?hl=en
-~----------~----~----~----~------~----~------~--~---
