Text Data - Signing/Encrypting?

[Derrick]

Hi All,

I wrote an app that reads text and/or xml data, will call it our "content".
We want to secure that content so that our app will know if someone has
modified it, or has produced their own content. I'm guessing I want some
sort of key generation based on the content to go along with the file? Can
anyone point me at an article or suggest a way to do this?

I've seen the encrypt/decrypt packages, but we don't want to encrypt.

Thanks in advance!

Derrick

 

[Nicholas Paldino [.NET/C# MVP]]

Derrick,

If you are not worried about the content being read, but just being
modified, then I would suggest hashing the message, and then encrypting the
hash.

You can use the classes in the System.Security.Cryptography namespace to
do this.

Hope this helps.

 

[Jon Skeet [C# MVP]]

I wrote an app that reads text and/or xml data, will call it our "content".
We want to secure that content so that our app will know if someone has
modified it, or has produced their own content. I'm guessing I want some
sort of key generation based on the content to go along with the file? Can
anyone point me at an article or suggest a way to do this?

I've seen the encrypt/decrypt packages, but we don't want to encrypt.

You basically want a hash - look at the
System.Security.Cryptography.MD5 class, and its ComputeHash method.

(You'll need to convert your text data into binary data using an
Encoding - I suggest using Encoding.UTF8.)