(C#) Get Certificates from .p12 / .pfx

A PKCS12 (.p12 / .pfx) is a container for holding a certificate, its private key, and the certs in the chain of authentication up to and possibly including the root CA cert. A .p12 is not required to contain certain things. It will contain whatever the creator of the .p12 decided to include. It's possible to contain just a private key, just a cert, many certs without private keys, or many certs with many private keys. Usually, a .p12 contains one certificate, its associated private key, and certificates in the chain of authentication.

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Chilkat.Pfx pfx = new Chilkat.Pfx();

bool success = pfx.LoadPfxFile("qa_data/pfx/test.pfx","pfx_password");
if (success == false) {
    Debug.WriteLine(pfx.LastErrorText);
    return;
}

// Iterate over the certs contained in the PFX
int numCerts = pfx.NumCerts;
int i = 0;
while (i < numCerts) {
    Chilkat.Cert cert = pfx.GetCert(i);

    Debug.WriteLine("--- " + Convert.ToString(i) + " ---");
    Debug.WriteLine(cert.SubjectDN);
    // Is this a root cert, or self-signed?
    Debug.WriteLine("Root: " + Convert.ToString(cert.IsRoot));
    Debug.WriteLine("Self-Signed: " + Convert.ToString(cert.SelfSigned));

    // If this certificate is not the root (self-signed), then get the issuer.
    // If the issuing certificate is contained in the PFX, then it will be found here..
    if (cert.SelfSigned != true) {
        Chilkat.Cert issuer = cert.FindIssuer();
        if (cert.LastMethodSuccess == false) {
            Debug.WriteLine("Issuer not found.");
        }
        else {
            Debug.WriteLine("Issuer: " + issuer.SubjectDN);

        }

    }

    i = i + 1;
}

// Usually, the user certificate is at index 0, its issuer is at index 1, etc. until we get to the root certificate.