How to use blowfish in C++ as an external dll in C#

Question

Hello,

It seems there's no blowfish in C# that would do the same as this one.So I decided to use it as an external and if it doesnt work again then translate the whole blowfish in C#. But first I'll try to use as an external.

Could you take a look at the C++ blowfish and tell me if I have to change the function parameters(some of them are LPBYTE,which is not included in C#).

Also,I'd be thankful if you tell me how to use them as an external dll(I have it compiled as a dll already),but the function parameters in C++ are frustrating me.

Edit: I need to call only Initialize,Encode and Decode.

Thanks in advance!

Answer 1

I've had a similar problem to this on a previous project. Having looked at the C++ code, it is using ECB as you suspected in your previous post. I think I see the reason why you get different results using Blowfish.NET (Arkain's suggestion). The C++ code casts the inputs into two DWORDs as it enciphers. I believe Blowfish.NET will be doing the right thing by preserving the byte order in the DWORDs it uses internally to encipher.

For example: In the C++ code, the bytes 0102030405060708 become 0x04030201 and 0x08070605. The .NET implementation will be becoming 0x01020304 and 0x05060708.