digital-signature

Is it possible to extract the visible signature (image of capture) of an signed PDF with the OSS libary PDFBox? Workflow: - list all signatures of a file - show with signatures include an visible signature - show which are valid - extract images of signatures (need to extract correct image for each signature) something in oop style like following would be awesome: PDFSignatures [] sigs = document.getPDFSignatures() sig[0].getCN() ... (Buffered)Image visibleSig = sig[0].getVisibleSignature() Found class PDSignature and how to sign a PDF, but not a solution to extract an visible signature as

While decrypting text using RSACryptoServiceProvider.Decrypt , I am getting the error: Error occurred while decoding OAEP padding. Here's my code: CspParameters cspParam = new CspParameters(); cspParam = new CspParameters(); cspParam.Flags = CspProviderFlags.UseMachineKeyStore; clsCertificates cc = new clsCertificates(); string a = ""; cc.OpenStoreIE(ref a); cc.SetProperties(); X509Certificate2 cert = new X509Certificate2(); cert = cc.x509_2Cert; RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(cspParam); //to gentrate private and public keys from the certificate rsa.FromXmlString

I want to generate a simple CMS signature using bouncycastle. This code works! Security.addProvider(new BouncyCastleProvider()); String password = "123456"; KeyStore ks = KeyStore.getInstance("PKCS12"); ks.load(new FileInputStream("c:/cert_123456.p12"), password.toCharArray()); String alias = (String)ks.aliases().nextElement(); PrivateKey key = (PrivateKey)ks.getKey(alias, password.toCharArray()); Certificate[] chain = ks.getCertificateChain(alias); CMSSignedDataGenerator generator = new CMSSignedDataGenerator(); generator.addSigner(key, (X509Certificate)chain[0], CMSSignedDataGenerator.DIGEST

I'm trying to build an application where the following happens: A client requests a PDF-hash from the server. The server generates the hash of a PDF-file and sends this to the client. The client signs this hash with his private key and sends the signed hash along with the public part of his own certificate. The server generates a new, signed PDF file. The problem I'm having with this: It seems impossible for the server to generate a to-be-signed hash without having the client's certificate available beforehand. I'd really prefer to create a solution where the server does not need to know the

Possible Duplicate: Digitally sign PDF files In the application a user will upload a PDF file and then upload a personal signature created using a digital pen. How can I embed this signature in the pdf file? Use a PDF editing library. I've used this one before: http://pdfsharp.com/PDFsharp/ JoeManiaci As far as I have been able to figure out, you can't programmatically sign the document and still have it be a valid signature. I am looking at this from the most strictest of positions though. I am a DoD contractor tasked with doing as much as I can automating the creating of pdf documents and

On iOS, the Certificate, Key, and Trust Services API contains the following padding types: kSecPaddingNone kSecPaddingPKCS1 kSecPaddingPKCS1MD2 kSecPaddingPKCS1MD5 kSecPaddingPKCS1SHA1 A user on the Apple CDSA mailing list says that "kSecPaddingPKCS1 [...] is the same as PKCS #1 1.5". The Certificate, Key, and Trust Services Reference annotates the latter three padding types ( kSecPaddingPKCS1MD2 , kSecPaddingPKCS1MD5 , and kSecPaddingPKCS1SAH ) with "Standard ASN.1 padding will be done, as well as PKCS1 padding of the underlying RSA operation". What is the difference to kSecPaddingPKCS1 ? Is

My task is the following: Retrieve my public and private key from the keystore I created. Use these keys to encrypt a paragraph using my RSA 2048-bit public key. Digitally sign the result using the DSA-SHA-1 signature algorithm. Save the digital signature output on a file called output.dat . The program below is throwing error : "java.security.InvalidKeyException: No installed provider supports this key: sun.security.provider.DSAPublicKeyImpl". import java.security.*; import java.security.KeyStore.*; import java.io.*; import java.security.PublicKey; import java.security.PrivateKey; import