The noble craft of software development

A secure desktop is the sort of thing you see when the UAC kicks in and asks you for permissions extraordinaire. Using a secure desktop, or to be precise, a separate desktop for sensitive inputs like passwords, can offer a certain amount of protection against those evil, softwarebased keyloggers. In order to create such a desktop, we need to use a few Win32 API functions.

We’ll start by using the Win32 functions in question in their native tongue, C, because that will introduce us to the bare essentials of desktop switching before we move on to C# and WPF. Read more

If you want to use the lean, mean and fast SQLite database in your .NET programs under Linux and Mono, using Mono.Data.SQLite might seem like the obvious choice, but you can actually do better. With a little effort, you can use System.Data.SQLite under Linux+Mono (and probably macOS too). There a couple of key benefits to be gained from this: Read more

When you’re playing with the sort of big integers used in, for example, cryptography, 64 bits just aren’t enough. In this post, I’ll compare and benchmark some of the alternatives that take .NET numerics beyond 64 bits. The benchmark results turn out to be a tale of the unexpected, to paraphrase Roald Dahl.

The test case is RSA signature verification, which uses the formula c=m^e mod n, where c, m and n are the same size as the RSA key (the public RSA key consists of n and e), typically 1024, 2048 or 3072 bits, while e usually is a mere 32 bits (usually holding the value 17 or 65537). In the test, I’ll use a 1024 bit key, because that conveniently enables me to reuse some F# code I wrote to verify RSA signed data written by EU digital tachographs. Read more

When using Microsoft’s Entity Framework, the ConcurrencyMode attribute for properties mapped to rowversion (a.k.a. timestamp) database columns, should be set to ConcurrencyMode.Fixed, to enable optimistic concurrency.

Unfortunately, due to a bug in the Entity Framework tools, you have to do this manually. The NuGet package EFConcurrencyModeTest makes it easy to write the unit tests needed to make sure that you have done so.

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