Can I use a digital signature in this scenario? With c#

I want to sign an xml document using a private key. And then when my client receives the software for them to be able开发者_运维知识库 to verify that the xml document hasnt changed by using a public key.

I want to distribut the same public key amongst all of my customers so that we can issue licenses to them.

Is this possible? I am using c# and .net.

Yes it is perfectly possible. Here is a comprehensive overview: How to: Verify the Digital Signatures of XML Documents with .NET

Also here is how to sign documents for later verification: In C#, sign an xml with a x.509 certificate and check the signature

Yes, this is possible. There are more important questions when putting together a solution.

• Do you want this verification to be done automatically by your program?
• Do you want to set up your own public key infrastructure?
• Does your company already have a public signing certificate?

Depending on the answers, you might not need to write any code.

There is also a nice article here about licenses using XML digital signatures: http://www.codeproject.com/KB/security/xmldsiglic.aspx