How to add Timestamp attribute to certification detail when signing pdf file

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I want to display the Timestamp attribute in the certificate as shown in the picture

enter image description here

What should I set in the Signature?

This is my code for add sign info:

private SignerInformation signTimeStamp(SignerInformation signer) throws IOException, TSPException {
    AttributeTable unsignedAttributes = signer.getUnsignedAttributes();

    ASN1EncodableVector vector = new ASN1EncodableVector();
    if (unsignedAttributes != null) {
        vector = unsignedAttributes.toASN1EncodableVector();
    }

    byte[] token = this.tsaClient.getTimeStampToken(signer.getSignature());

    ASN1ObjectIdentifier oid = PKCSObjectIdentifiers.id_aa_signatureTimeStampToken;
    ASN1Encodable signatureTimeStamp = new Attribute(oid, new DERSet(ASN1Primitive.fromByteArray(token)));

    vector.add(signatureTimeStamp);
    Attributes signedAttributes = new Attributes(vector);
    // replace unsignedAttributes with the signed once
    return SignerInformation.replaceUnsignedAttributes(signer, new AttributeTable(signedAttributes));
}
signature digital-signature timestamp pdf
1 Answers

To sum up the comments...

Inspecting your example document it became clear that the timestamp you applied is alright. In particular you should get the lower message you marked in Certificate Viewer dialog screen shot:

The path validation and revocation checks were done as of the secure (timestamp) time.

On the other hand your code has no influence on whether or not you get the other entry you marked in that screen shot:

Certificate data: TimeStamp - URI = http://aatl-timestamp.globalsign.com/tsa/v4v5effk07zor410rew22z

That entry is an extension of the signer X.509 certificate in which the issuer of that certificate provides the address of a time stamp service that may be used for timestamping signatures created by the private key associated with that certificate.

Thus, that entry does not necessarily contain the server used to create the actual timestamp, it's merely a proposition or recommendation.

So if the box in your screen shot that connects with the two markers claims some necessary relation between the marked TSA URL and reference to a secure timestamp time, it is wrong.

user_17292650
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