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Colin Percival

daemonology.net

Not on this site, but still likely to be of interest, is my Tarsnap online backup service .

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1

A Canadian payroll dependency chart

Unfortunately, like most aspects of the tax system, this steadily increases in complexity, and this year with the Canada Pension Plan including not just "base" premiums and "additional" premiums but also "second additional premiums", I needed to rewrite my spreadsheet from scratch; and also very unfortunately, the…

2

Zeroing buffers is insufficient

With a bit of care and a cooperative compiler, we can zero a buffer — but that's not what we need. What we need to do is zero every location where sensitive data might be stored. Remember, the whole reason we had sensitive information in memory in the first place was so that we could use it; and that usage almost…

3

How to zero a buffer

Now, we don't want to truly change the observable behaviour of our software — but fortunately the C standard has a more liberal concept of "observable" than most people. In particular, the C standard states that the observable behaviour includes accesses to volatile objects . What is a volatile object, you ask? It is…

6

Tarsnap email confirmation bypass

One consequence of these unsolicited security scans is that — since they feed a variety of inputs to forms, including the account creation form — I see a lot of obviously fake signup attempts (alas, none yet from the world's most obviously fake domain name ). These are harmless, since the signup code sends out a…