URL-Safe Timestamps using Base64

Passing around timestamps in URLs is a common task. We usually want our URLs to be as shortest as possible. I’ve found using Base64 to result in the shortest URL-safe representation, just 6 chars. This compares with the 12 chars of the naive way, and 8 chars when using hex representation.

The following Python functions allow you to build and read these 6 chars URL-safe timestamps:
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Hash Puppy 0.2

This is an update for my simple easy-to-use checksum calculator. It supports md4, md5, and sha1 hash functions. I wrote the project as a way to experience and learn Qt.

Changes since the previous version (Hash Puppy 0.1) include ability to abort a checksum calculation and improved GUI responsiveness. Also there were other minor tweaks to make Hash Puppy easier to use.
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Improved FTP Backup for WordPress

This script backups both the database and files of a WordPress blog into a remote FTP server (while keeping a local copy). It’s an update of my WordPress Backup to FTP script. The main changes are auto-detecting database settings and better support for caching plugins (specifically WP-Cache). The new version makes it easier to backup multiple WordPress blogs to the same FTP server.
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“CC Yourself” and Spam

Every good web programmer will note that the following contact form markup is probably flawed

<form>
...
    <input type="hidden" name="to" value="support@example.com" />
...
</form>

as it is likely that if the value of the “to” field changes the message will be sent to the modified address. The problem with this kind of functionality is that it allows a malicious user to send emails from your mail server. More specifically, it can allow spammers to user your benign server t send their spam (and as a side effect you might be flagged as a spammer yourself).

As this case is pretty obvious one doesn’t see many real-life uses of it anymore (but careless programmers used it more often n the past until they learned better). However one can achieve similar goals (spam-wise) by utilizing a common feature in contact forms: the “CC yourself” checkbox.

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Disable Touchpad Tapping in Kubuntu

In Ubuntu (gnome) there is an easy graphical way to disable tapping on the touchpad. However, KDE lacks such thing. But lacking graphical configuration doesn’t mean this should be difficult. All you need is the gsynaptics package. The package provides a small utility called synclient. Now you can disable tapping by doing

 synclient TapButton1=0

To disable the tapping permanently you should use the following to run the command at the start of every KDE session.

echo "synclient TapButton1=0" > ~/.kde/env/disable-tapping.sh

NVidia driver fails to initialize after X restart

This is mainly a note to myself. Sometimes when the X server is restart it complains that nvidia driver couldn’t be initialized and that no screens were found. This may be a result of a version mismatch between X11’s and the kernel’s nvidia module. The solution is to

modprobe -r nvidia

before restarting the X server.

Blocking IP Range using UFW

Uncomplicated Firewall (ufw) is one of the greatest frontends to IPTables I’ve encountered. It is very simple to use and I just wish it was also available for Gentoo. Up until recently everything went smoothly for me and ufw, but we hit some rough waters when I’ve tried to block an IP range.

To block an IP or IP range in ufw you should do

sudo ufw deny from 188.162.67.197/21

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