Get a C# byte array equal to a php hex string

Question

So I have this piece of php code that I\'m not allowed to modify for now, mainly because it\'s old and works properly.

Warning! Very bad

Answer 1

The hash function will return the same number of bytes whatever the input, so I suspect it is a difference in how you convert the resulting byte[] back to a string in C# compared to the PHP implementation.

The PHP docs say that the hash function output the result in lower case hexits. This is absolutely not the same as the UTF8 encoding that you are returning.

There isn't a built in framework way to do this, but check out this SO question for several different methods.

Also worth noting is that you do not specify the Padding value in your C# code. AES-CBC is a block cipher and will need to use some padding scheme. You may well get a padding exception. I think that it will need Zero padding (docs)

aes.Padding = PaddingMode.Zeros

but I'm not 100%