Archives 2010

Setting up a DHCP test environment in QEMU

My current project must run against a DHCP server which has to have a fairly exotic configuration (not really one I'd want running on my home network), and I want to be able to blow away and re-create the client constantly as I test installation procedures and the like.  So, since we're on Fedora 10 ...

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Fedora 10 without the Cruft

Wound up stuck at the Caffe for almost 3 hours as my supposedly minimal Fedora 10 install churned on my non-suspend-capable laptop.  Turns out that you have to deselect *every* checkbox in the Fedora 10 installer to get a minimal install, even things like system tools, text-editors and the like.  The google key word to ...

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Upstart seems kinda nice

Been doing system-level wiring for a low-level process for the last few hours, target is Fedora 10, so I can (theoretically) use Upstart for the init scripts... pretty slick stuff, the configs are simple, and I can create my 4-5 somewhat-interdependent processes such that they just kick each other off based on sending events.  The ...

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Extract all fields of a DER-encoded PKCS7 file?

Say you have a PKCS#7 file with an embedded code-image as a field, how would you go about extracting that field's contents?  pyOpenSSL doesn't seem to have mechanisms for extracting/viewing arbitrary fields from PKCS7.  pyasn1 can load the structures, but of course it doesn't have access to the meaning of the fields, and it doesn't ...

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Generic Binary-Data Pack/Unpack Module?

Having just written yet another module to pack/unpack data into a particular binary format, I'm wondering if someone has a more effective method they'd like to share?  I'm thinking some module that can handle RLE/TLV type stuff, complex "encodings" such as utf-8 continued charcters, struct-like pack/unpack for static elements, efficient loading of arrays, and bit-field ...

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tgext.command 0.2 is out...


Adds support for instantiating Beaker's Cache from the config file (i.e. you can do cache-specific operations such as edge-triggered-cache-clearing in your utility scripts).  That's mostly useful if you have content-modifying scripts and want to clear/populate the cache when the script runs. Available in PyPI.

Don't make me guess, Gentle Spec Writer

Say you were writing a major standard, something implemented by thousands of companies. Say, one which specified, among other things, a format for public key files. Might it be appropriate to say "use a BER-encoded x509" certificate (with some (standard) x509 extensions)? Or would you:

  • declare that you require a "special" binary format for your ...

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Remote networking is a PITA

Setting up networking on a remote machine is a bit of a pain.  If you happen to make the smallest of slips your ssh session gets black-holed and you're up it.  You can try using a `shutdown +10 -r` command in another session to reboot-on-failure, but there's always the chance that you forget to set ...

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RunSnakeRun 2.0.0b6 (and SquareMap 1.0.0b25) released

Marius contributed quite a few changes (restructuring to support VirtualEnv-ing, enhanced percentage reporting), the source-code-view is also there, the home-view is more likely to be reasonable (though it can still get messed up with threaded views).  SquareMap is now explicitly a dependency and has been restructured to work with `setuptools develop` in a virtualenv.  Available ...

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Say it with me: Errors should never pass...

Say you were writing a program that takes a "config-file" parameter and you were (explicitly) passed a filename that, for whatever reason, you couldn't load. Is the proper operation to exit and report an error, log a warning and continue with defaults, or load a default filename silently?

In this particular case, app-armour was configured ...

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