Rafael, Rafael Wampfler wrote: > For my understanding: > RSA/1024 signature is 128bytes long (which is 1024 / 8) > DSA signature is shorter. Is the length variable?
Unfortunately I have no idea... I have not yet had to tinker with anything but RSA based signatures... ;) Rafael Wampfler wrote: > sig.getEncodedPKCS1().length says the length is 49. Reserving new byte[49] > or a bit more or less also gives an invalid signature. Is there a way to > calculate the length of a signature before creating it? How big should i > make this array? Your sample file looks like there was place for two additional bytes (four additional hex characters), so I would think 47 is your number. Oops, as Andreas just mentioned, the subfilter adbe.x509.rsa.sha1 requires rsa signatures (Andreas: in spite of the name, though, sha1 is not required, at least not since PDF 1.6 anymore: "Despite the appearance of sha1 in the name of this SubFilter value, supported encodings shall not be limited to the SHA1 algorithm. The PKCS#1 object contains an identifier that indicates which algorithm shall be used."). I had the wrong "algorithms allowed in spite of subfilter name" on my mind. Regards, Michael. PS: Therefore you should take PKCS#7 generating code as template. Visit http://itextpdf.sourceforge.net/howtosign.html for inspiration and search for adbe.pkcs7.detached. -- View this message in context: http://itext-general.2136553.n4.nabble.com/Digital-signature-with-DSA-key-tp3264088p3264339.html Sent from the iText - General mailing list archive at Nabble.com. ------------------------------------------------------------------------------ The modern datacenter depends on network connectivity to access resources and provide services. The best practices for maximizing a physical server's connectivity to a physical network are well understood - see how these rules translate into the virtual world? http://p.sf.net/sfu/oracle-sfdevnlfb _______________________________________________ iText-questions mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/itext-questions 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
