adamec, adamec wrote > I still quite donet understand. When I sign a pdf with iText by means of > private key I provide (using PrivateKeySignature), I also create hash for > document. Then, this hash is signed afterwards and alsdo attached to pdf.
The difference starts with which document bytes are hashed. If I understand you right, you hashed the bytes of the original document. For the integrated PDF signature, though, that original document first is prepared for integration of a signature, and then the hash is calculated for that prepared document (with the exception of the range of bytes where the signatrue container will be embedded). Thus, you hashed the wrong data. The difference continues with which hash is to be encrypted to create the actual signature: iText embeds CMS signature containers. The respective SignerInfo inside contains an encrypted hash as signature value, but this hash value is not the hash calculated for the document bytes but instead the hash value calculated for the signed attributes of the SignerInfo and the document hash merely is the value of one of these signed attributes. (This, BTW, is not PDF specific but valid for non-trivial CMS/PKCS#7 signature containers in general.) Regards, Michael -- View this message in context: http://itext-general.2136553.n4.nabble.com/PKCS-1-signature-iText-signed-pdf-tp4657691p4657702.html Sent from the iText - General mailing list archive at Nabble.com. ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_d2d_feb _______________________________________________ iText-questions mailing list iText-questions@lists.sourceforge.net 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
