Implementing AES-GCM with 128-bit blocks and 256-bit key

AES with a blocksize of 256 bits doesn't exist. Rijndael does? Is that what you mean? Have a look at BouncyCastle. It's on NuGet. – Luke Joshua Park May 07 '18 at 08:34
You are right. I have investigated this problem and edited my post. – Emanuele May 07 '18 at 09:35
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I suggest you read the C# example in [this repository](https://github.com/luke-park/SecureCompatibleEncryptionExamples). There are examples for 9 other languages as well, if that helps. – Luke Joshua Park May 07 '18 at 09:38
It's very similar to link I posted.... Can you explain the differences? In your solution I have to change some parameters... And in .Net 2.0? – Emanuele May 07 '18 at 09:51
The example I posted is compatible across standard implementations (hence the number of languages it is translated into). The link you posted uses a non-standard nonce size that makes it difficult to use in other languages. Other than that, pretty similar. At the end of the day, if you aren't any good at cryptography, you probably shouldn't be using it! Hire someone that knows what they are doing. – Luke Joshua Park May 07 '18 at 09:55
Are you referring to 128? It must be 12. So i need to edit your sample only for key size (256) – Emanuele May 07 '18 at 10:07
That is correct. – Luke Joshua Park May 07 '18 at 10:08
And in Net 2.0? I can write something similar? BouncyCastle is for > 3.5. – Emanuele May 07 '18 at 10:09
Well, no, because all that code uses methods from BouncyCastle... – Luke Joshua Park May 07 '18 at 10:10
In your opinion, in .Net 2.0 can I use existing `RijndaelManaged`? – Emanuele May 07 '18 at 10:31
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No, GCM is not supported in .NET 2.0 – Luke Joshua Park May 07 '18 at 13:19
Thanks. I'm checking your code in c#. Key size has not to be 256 -as told before - but 32! – Emanuele May 07 '18 at 13:31
You're confusing bits and bytes. – Maarten Bodewes May 07 '18 at 15:41

Implementing AES-GCM with 128-bit blocks and 256-bit key

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