Inspirated

 
 

June 19, 2014

cl-ecc: A prototype implementation of ECC in Common Lisp

Filed under: Blog — admin @ 11:20 pm

Recently I’ve been reading through these excellent books in my spare time:

To ramp-up on both subjects with one shot I wrote an implementation of Elliptic Curve Crypto in Lisp. So far, it does EC versions of Diffie-Hellman, ElGamal and DSA. Some rudimentary testing was performed using the NIST-P192 curve and its corresponding ECDSA test vectors.

The package is available at GitHub in the krkhan/cl-ecc repository. Here’s a quick snippet of what the code looks like:

(defconstant *p17-curve*
  (make-instance
    'Curve
    :a 2
    :b 2
    :p 17
    :g (make-instance
         'Point
         :x 5
         :y 1)
    :n 19))

And an ECDSA with this curve:

(def-positive-test test-ecdsa ()
  (let* ((c *p17-curve*)
         (bob-priv 3)
         (bob-pub (ecdh-gen-pub c bob-priv))
         (msghash 8)
         (k 7)
         (sig (ecdsa-gen-sig c msghash bob-priv k)))
    (assert (sig-equalp sig (make-instance 'ECDSASig :r 0 :s 12)))
    (ecdsa-verify-sig c msghash sig bob-pub)))

As a disclaimer — even though I know no one would be stupid enough to do so — please do not use this code in a production environment. It was written for recreational purposes by a hobbyist who is bad with cryptography and even worse with Lisp. On the other hand, if you have any suggestions/patches, feel free to create an issue/pull-request on GitHub.

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August 23, 2011

Tarball generator for Git commits

Filed under: Blog — admin @ 12:56 am

While working for GSoC last year I kept track of Bazaar patches I sent in for Arsenal. This year I was using Git and as the need arose to generate a submission tarball for my commits I wrote this small utility script: git-generate-tarball.py.

To invoke the script, change into your Git repository and provide an author name and a file as an argument:

[krkhan@orthanc tor]$ /home/krkhan/Downloads/git-generate-tarball.py "Kamran Riaz Khan <krkhan@inspirated.com>" /home/krkhan/Downloads/tor-gsoc-krkhan.tar.gz

generating tarball for commits between Mon May 23 00:00:00 2011 +0000 and Mon Aug 22 19:00:00 2011 +0000
generating patch for commit 5a801a8c8b71c9551a80913398135809cb10cecd

/home/krkhan/Downloads/tor-gsoc-krkhan.tar.gz created

The default starting and ending dates for the commits correspond to the schedule for GSoC 2011. You can specify a starting date for the commits you want to be packaged using the --since argument:

[krkhan@orthanc arm]$ /home/krkhan/Downloads/git-generate-tarball.py --since="August 1, 2011" "Kamran Riaz Khan <krkhan@inspirated.com>" /home/krkhan/Downloads/arm-gsoc-krkhan.tar.bz2

generating tarball for commits between August 1, 2011 and Mon Aug 22 19:00:00 2011 +0000
generating patch for commit 546ca73259d7863e3efe5e11e09c023c2790a2f6

/home/krkhan/Downloads/arm-gsoc-krkhan.tar.bz2 created

Same goes for the --before argument:

[krkhan@orthanc tor]$ /home/krkhan/Downloads/git-generate-tarball.py --before="August 14, 2011" "Kamran Riaz Khan <krkhan@inspirated.com>" /home/krkhan/Downloads/tor-gsoc-krkhan.tar.gz

generating tarball for commits between Mon May 23 00:00:00 2011 +0000 and August 14, 2011
generating patch for commit 5a801a8c8b71c9551a80913398135809cb10cecd

/home/krkhan/Downloads/tor-gsoc-krkhan.tar.gz created

Or a combination of both:

[krkhan@orthanc arm]$ /home/krkhan/Downloads/git-generate-tarball.py --since="August 1, 2011" --before="August 14, 2011" "Kamran Riaz Khan <krkhan@inspirated.com>" /home/krkhan/Downloads/arm-gsoc-krkhan.tar.gz

generating tarball for commits between August 1, 2011 and August 14, 2011
generating patch for commit 546ca73259d7863e3efe5e11e09c023c2790a2f6

/home/krkhan/Downloads/arm-gsoc-krkhan.tar.gz created

If you want to leave the dates undefined you can leave the arguments empty. For example, the following command shall process all commits before June 1, 2011:

[krkhan@orthanc arm]$ /home/krkhan/Downloads/git-generate-tarball.py --since= --before="June 1, 2011" "Kamran Riaz Khan <krkhan@inspirated.com>" /home/krkhan/Downloads/arm-gsoc-krkhan.tar.gz

generating tarball for commits before June 1, 2011
generating patch for commit 8b4dc162f75d5129e41f028c7253b7b265c8af76

/home/krkhan/Downloads/arm-gsoc-krkhan.tar.gz created

Hope this helps fellow GSoCers.

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March 30, 2011

GSmolt: A GTK+ frontend for Smolt

Filed under: Blog — admin @ 1:46 am

Smolt is a hardware profiler for Linux distributions which makes it easier for end-users to report back their machine configurations to a centralized database. Mike McGrath provides an excellent backend for developing Smolt GUIs which I have coupled with GTK+ for GSmolt:

GSmolt Screenshot
GSmolt Send Screenshot
(Click on the thumbnails for larger versions.)

The script can be found at the gsmolt repository on GitHub. Things on todo list include profile reporting in a separate thread and better error handling. I’ll provide RPM and Deb packages when the code is ready for a public release.

As a side note, this is the first project I have tracked using GitHub (as opposed to Launchpad + Bazaar). While Launchpad has its added advantage of PPAs which make it easier to push out public releases for Debian derivatives, I’m liking the Git experience so far. Hopefully some day Copr shall mature to a point where it can be the end-all, be-all Launchpad alternative for Fedora users.

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