Java

Get an S/MIME Signing Time

Demonstrates the Chilkat Mime.GetSignatureSigningTimeStr method, which returns the CMS signingTime attribute for the signer at a zero-based index, as an RFC 822-style date string in GMT. The only argument is the signer index.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: This is the timestamp the signer asserted at signing — useful for "when was this signed" audit trails and for evaluating whether the signing certificate was valid at that moment. Because it is a signed attribute, it is tamper-evident. Guard the call with HasSignatureSigningTime, since the attribute is optional. Note it is the signer's claim, not a trusted third-party timestamp.

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Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    CkMime mime = new CkMime();
    success = mime.LoadMimeFile("qa_data/signed.eml");
    if (success == false) {
        System.out.println(mime.lastErrorText());
        return;
        }

    //  After verifying, get the CMS signingTime for each signer that has one, as an RFC 822 date string
    //  in GMT.  The only argument is the zero-based signer index.
    success = mime.Verify();
    if (success != true) {
        System.out.println(mime.lastErrorText());
        return;
        }

    int n = mime.get_NumSignerCerts();
    int i;
    for (i = 0; i <= n - 1; i++) {
        //  Only signers that included a signing time have one to retrieve.
        if (mime.HasSignatureSigningTime(i)) {
            String signingTime = mime.getSignatureSigningTimeStr(i);
            if (mime.get_LastMethodSuccess() == false) {
                System.out.println(mime.lastErrorText());
                return;
                }

            System.out.println("Signer " + i + " signing time: " + signingTime);
            }

        }
  }
}