Thank you very much for your answer. I mean with P=1, 2, 3 the access permissions of the DocMDP transform parameters dictionary described in 32000-1: 2008: P=1 No changes to the document shall be permitted; any change to the document shall invalidate the signature. P=2 Permitted changes shall be filling in forms, instantiating page templates, and signing; other changes shall invalidate the signature. P=3 Permitted changes shall be the same as for 2, as well as annotation creation, deletion, and modification; other changes shall invalidate the signature.
I've implemented the validation of "P=1" simply verifying the signature on the byterange and checking that the byterange covers the entire document. This was ok for me. Now i'd like to implement also some methods that allow me to verify documents with P=2 and P=3. The problem, that 2 years ago seemed to be open, is to compare the revisions to find out if the changes between the certified revision and the next revisions are allowed. I'm wondering if some recent improvements can help to solve the problem. Thank you again. Francesca Il giorno 16/gen/2012, alle ore 18.07, Paulo Soares ha scritto: > I'm not sure what you are refering to. P=1 means that the document can't be > changed and that can be checked just by verifying the signature. A certified > signature in this case is the same as a plain signature. > > Paulo > > -----Original Message----- > From: fmerighi [mailto:[email protected]] > Sent: Monday, January 16, 2012 4:54 PM > To: [email protected] > Subject: [iText-questions] Verify certified (with transform method DocMDP) > signatures > > Hi. I read some posts of about 2 years ago, in which iText developers said > that iText doesn't support validation of signatures certified by a DocMDP > transformation. > I wrote my method to validate signatures with DocMDP and P=1. > Do newer releases add some support for handling certified signatures? > Thanks. > > > -- > View this message in context: > http://itext-general.2136553.n4.nabble.com/Verify-certified-with-transform-method-DocMDP-signatures-tp4300147p4300147.html > Sent from the iText - General mailing list archive at Nabble.com. > > ------------------------------------------------------------------------------ > RSA(R) Conference 2012 > Mar 27 - Feb 2 > Save $400 by Jan. 27 > Register now! > http://p.sf.net/sfu/rsa-sfdev2dev2 > _______________________________________________ > iText-questions mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/itext-questions > > iText(R) is a registered trademark of 1T3XT BVBA. > Many questions posted to this list can (and will) be answered with a > reference to the iText book: http://www.itextpdf.com/book/ > Please check the keywords list before you ask for examples: > http://itextpdf.com/themes/keywords.php > > ------------------------------------------------------------------------------ > RSA(R) Conference 2012 > Mar 27 - Feb 2 > Save $400 by Jan. 27 > Register now! > http://p.sf.net/sfu/rsa-sfdev2dev2 > _______________________________________________ > iText-questions mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/itext-questions > > iText(R) is a registered trademark of 1T3XT BVBA. > Many questions posted to this list can (and will) be answered with a > reference to the iText book: http://www.itextpdf.com/book/ > Please check the keywords list before you ask for examples: > http://itextpdf.com/themes/keywords.php ------------------------------------------------------------------------------ RSA(R) Conference 2012 Mar 27 - Feb 2 Save $400 by Jan. 27 Register now! http://p.sf.net/sfu/rsa-sfdev2dev2 _______________________________________________ iText-questions mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/itext-questions iText(R) is a registered trademark of 1T3XT BVBA. Many questions posted to this list can (and will) be answered with a reference to the iText book: http://www.itextpdf.com/book/ Please check the keywords list before you ask for examples: http://itextpdf.com/themes/keywords.php
