Documentation

sar Cheatsheet

sar can be an incredibly helpful utility when examining system performance, but if not used regularly it's easy to forget which flags to use.

This short post details a number of useful arguments to pass

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ls -l Shows Question Marks instead of Permissions

Occasionally, when running ls -l within a directory, you might find that the output shows question marks (?) instead of the usual permissions indicators:

ben@Queeg:~$ ls -l ~/test
ls: cannot access /var/www/html/Vx/Notes: Permission denied
total 0
d????????? ? ? ? ? ? Notes

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Avoiding BCC Leaks with Exim

This issue is, by no means, Joomla specific - but Joomla's mass mail functionality provides a good example of what can go wrong.

The expectation that most users have, is that the list of recipients BCC'd on an email will never be visible to any of those recipients.

Unfortunately, whether or not that's the case may well depend on the Mail Transport Agent (MTA) that you are using.

Those familiar with Joomla's Mass Mail feature will know that by default, recipients are BCC'd - unfortunately, if you're using Exim (which most CPanel servers, for example, are) then you may in fact find that those receiving your message can see exactly who it was sent to.

Whether or not this BCC Leak is visible to the recipients will depend on what mail client they use (assuming they're not in the habit of looking at the mail headers anyway....), but those using Google Apps/Google Mail will have the list clearly presented to them when viewing the mail.

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PGP Encrypted Text Chat Via DNS

In a recent post, I alluded to having given a little bit of thought to ways in which clandestine communications could be achieved.

Having given a little more thought to the idea, I was unable to resist the temptation to build a small proof of concept - if only to see whether there were any obstacles that I hadn't considered.

This post is the documentation for DNSChat - a small proof of concept enabling PGP encrypted text chat using DNS Queries as a transport mechanism

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Installing Mailpile on CentOS 6

I've been meaning to play around with Mailpile since the beta was released back in September. Thanks to a bout of insomnia I finally found time, though it turns out that getting it up and running on CentOS 6 is initially something of a pain.

This documentation details the steps required to install and run Mailpile on CentOS 6

DISCLAIMER: For reasons I'll discuss in a separate post, at time of writing I'd only recommend following these steps if you want to test/play with Mailpile - Personally I don't feel at all comfortable with the idea of using Mailpile in production in it's current state.

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