I need to lock a pdf after applying a signature, I need the output file to look like this one: locked as you can see it says “locked by signature”, I tried adding the lock like this when I get the pdf signature appearance: but all I have got in return is this: mine only a message that says “…
Tag: digital-signature
How to get CMS (PKCS#7) from PKCS#1 Zeal id integration
I am integrating CSC2QR zeal id integration. where i am sending the Base64 URL encoded SHA256 hash (OGRlY2M4NTcxOTQ2ZDRjZDcwYTAyNDk0OWUwMzNhMmEyYTU0Mzc3ZmU5ZjFjMWI5NDRjMjBmOWVlMTFhOWU1MQ==) for signature and in response I am getting PKCS#1 raw signature . I am stuck on how I can use this information to digita…
How to verify EU COVID Vaccine QRCode Signature in Java?
Is there anyway to verify the signature of the EU Covid Vaccine QR Code and make sure the QR Code was issued by an authorized entity? Answer Thanks to Gaetano Piazzolla who recently wrote an article on how to verify Green-Pass QR Code Signature. Here is the article link: Green-Pass QR Code Signature Verificat…
How to remove Spire.XLS signature from pdf File?
I’m working on java, i have an excel file named “file.xlsx” that i want to convert to pdf using Spire.XLS , this is the code i wrote for that : The pdf file is generated but with a signature : Evaluation Warning : The document was created with Spire.XLS for Java , i’m wondering about h…
How to determine if an apk is signed in Java?
I’m building an Java Android App in Android Studio. In my onCreate function I wand to determine if the App has been build with or without a certificate. But by now, I get no Certificate Information at all. output: Answer You have to use getPackageInfo instead of getPackageArchiveInfo. When you do so, ge…
Digital signatures attached to the file
I need to implement digital signatures to my web app. I followed this and this example, and have successfully signed and verified given file. My questions are regarding the flow: I can export the signature, so what should I do with the signature? Save it in the database? If I attach signature to the file usin…
How to retrieve my public and private key from the keystore we created
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 …
KeyUsage does not allow digital signatures
I’m trying to send HTTPS request from my Java EE program to the host that requires certificate authentication. I have a proper keystore file, truststore with imported CA, the listing of both shows that certificates are inside. But I receive the following error: Viewing the certificate contents in the pa…