Package com.bfo.box

Class C2PAStore

java.lang.Object
com.bfo.box.Box
com.bfo.box.JUMBox
com.bfo.box.C2PAStore
public class C2PAStore extends JUMBox

The store box is the top-level box for any C2PA object. It contains one or more manifest boxes which must be added to getManifests()

Here's an example showing how to create a new C2PAStore. It uses the C2PAHelper class to embed the store in JPEG file. 

  C2PAStore c2pa = new C2PAStore();
  C2PAManifest manifest = new C2PAManifest("urn:manifestid");
  c2pa.getManifests().add(manifest);
  C2PAClaim claim = manifest.getClaim();
  C2PASignature sig = manifest.getSignature();
  claim.setFormat("image/jpeg");
  claim.setInstanceID("urn:instanceid");
  manifest.getAssertions().add(new C2PA_AssertionHashData());
  Json schemaJson = Json.read("{\"@context\":\"https://schema.org/\",\"@type\":\"VideoObject\",\"name\":\"LearnJSON-LD\",\"author\":{\"@type\":\"Person\",\"name\":\"Foo Bar\"}}");
  manifest.getAssertions().add(new C2PA_AssertionSchema("stds.schema-org.CreativeWork", schemaJson));

  KeyStore keystore = KeyStore.getInstance("PKCS12");
  keystore.load(new FileInputStream(keystorefile), keystorepassword);
  PrivateKey key = (PrivateKey)keystore.getKey(keystorealias, keystorepassword);
  List<gX509Certificate> certs = new ArrayList<X509Certificate>();
  for (Certificate c : keystore.getCertificateChain(keystorealias)) {
      certs.add((X509Certificate)c);
  }
  manifest.getSignature().setSigner(key, certs);
  Json j = C2PAHelper.readJPEG(new FileInputStream("unsigned.jpg"));
  C2PAHelper.writeJPEG(j, c2pa, new FileOutputStream("signed.jpg"));
and here's an example showing how to read the file back and verify it 
  Json j = C2PAHelper.readJPEG(new FileInputStream("signed.jpg"));
  if (j.has("c2pa")) {
    C2PAStore c2pa = (C2PAStore)new BoxFactory().load(j.bufferValue("c2pa"));
    C2PAManifest manifest = c2pa.getActiveManifest();
    manifest.setInputStream(new FileInputStream("signed.jpg"));
    boolean valid = true;
    for (C2PAStatus status : manifest.getSignature().verify(null)) {
      System.out.println(status);
      if (status.isError()) {
        valid = false;
      }
    }
  }
Since:
5
See Also:

  • Constructor Details

    • C2PAStore

      public C2PAStore()
      Create a new C2PAStore

  • Method Details

    • getManifests

      public List<C2PAManifest> getManifests()
      Return a live list of the manifest objects in this store
      Returns:
      the list of manifests

    • getActiveManifest

      public C2PAManifest getActiveManifest()
      Return the active manifest, which is just the last one in the list returned by getManifests()
      Returns:
      the active manifest

    • toJson

      public Json toJson()
      Return a representation of this store as a single Json object. The returned value is not live, changes will not affect this object. The object should be largely comparable to the output from c2patool
      Returns:
      the json