How to check if a certificate is signed by yourself?

Question

I am using C # .NET and you need to install a bunch of certificates in the Windows certificate store.

I need to check which of these certificates are root certificates (i.e. self-signed), so I can install them in the trusted root certificate store.

I am using the standard class X509Certificate2 . My current idea is to check if the Issuer and Subject tags are the same.

I noticed that X509Certificate2 has Issuer - IssuerName and Subject - SubjectName .

Is it better to compare Issuer with Subject or IssuerName with SubjectName ? Or does it not matter?

Also, is this a reliable method or am I better off using a different approach?

Answer 1

See this post: java - find if the certificate is self-signed or CA is signed

Until it is C #, comment from the notes to the solution

If the subject and the issuer match, it is self-signed

means that you correctly know how you check it.

IssuerName and SubjectName return a DistinguishedName that contains RawData (a byte[] containing raw information for the issuer / entity). It is best to compare this field, although I believe that comparing Subject and Issuer is also correct.

So you could write something like this:

 public static bool IsSelfSigned(X509Certificate2 cert) { return cert.SubjectName.RawData.SequenceEqual(cert.IssuerName.RawData); }