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Eastrall / EntityFrameworkCore.DataEncryption

A plugin for Microsoft.EntityFrameworkCore to add support of encrypted fields using built-in or custom encryption providers.
MIT License
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Dynamic IV not working on v4.0.0 #46

Closed DerStimmler closed 1 year ago

DerStimmler commented 1 year ago

Since version 4.0.0 you have to provide an initialization vector to the constructor of AesProvider. According to the release notes, you can provide null for the initialization vector to use dynamic IV.

The problem is that the constructor throws an ArgumentNullException if the IV is null.

https://github.com/Eastrall/EntityFrameworkCore.DataEncryption/blob/0beb7361a1c6c989bf17ccac2df98b1988f254c8/src/EntityFrameworkCore.DataEncryption/Providers/AesProvider.cs#L37

Is there a way to still use dynamic IV, or do I have to switch to a fixed one?

Eastrall commented 1 year ago

At the begining when I reworked the AesProvider (and wrote the release note) I was planning on keeping the dynamic IV support. But realised that it was something really specific and shouldn't be part of the library (just like the migration support) simply because it formats the output by adding 16 bytes at the begining of the array. This approach works well, but let's say you'd want these 16 bytes at the end of your array, or maybe in the middle of your encrypted data. It will not suit everyone's need. So, I decided to remove the support and forgot to update the release note. I apologize for that.

If you want to use a dynamic IV on your AES encryption, you will have to create your own encryption provider and implement it on your own. You can take inspiration of the V3.X encryption provider that still supports dynamic IV.

I'll correct the release note right away. Thanks for reporting it! 😄

DerStimmler commented 1 year ago

Thanks for the clarification.

Eastrall commented 1 year ago

You're welcome. I'm closing this issue. If you have any other question, please open a new issue.

DerStimmler commented 1 year ago

In case someone else wants to keep using dynamic IV: Here is an implementation of a custom IEncryptionProvider for v4.0.0 based on the AesProvider of v3.x.

https://gist.github.com/DerStimmler/ee6ae4b10c9d2e58dc5c63e087e1fb62

Uli-Armbruster commented 1 year ago

Great, thanks to all of you!

hfaran commented 11 months ago

@DerStimmler thanks a lot! Just migrated to .NET 7 and needed to move to a newer version of this package (from 2.0.0 to 4.0.1) so this saved me since I had existing data in a database to work with.