Unable to sign document after editing PDF

[moritz76]

Is your feature request related to a problem? Please describe.
After editing a PDF in the browser to highlight something or insert an image, LibreSign throws an error when I try to sign the document: "Internal error. Please contact an administrator."

In the Nextcloud log, I find a lot of entries related to this action:

[libresign] Fehler: [{"file":"\/var\/www\/nextcloud\/apps\/libresign\/lib\/Handler\/JSignPdfHandler.php","line":105,"function":"signWrapper","class":"OCA\\Libresign\\Handler\\JSignPdfHandler","type":"->"},{"file":"\/var\/www\/nextcloud\/apps\/libresign\/lib\/Handler\/JSignPdfHandler.php","line":76,"function":"signUsingVisibleElements","class":"OCA\\Libresign\\Handler\\JSignPdfHandler","type":"->"},{"file":"\/var\/www\/nextcloud\/apps\/libresign\/lib\/Handler\/Pkcs12Handler.php","line":133,"function":"sign","class":"OCA\\Libresign\\Handler\\JSignPdfHandler","type":"->"},{"file":"\/var\/www\/nextcloud\/apps\/libresign\/lib\/Service\/SignFileService.php","line":275,"function":"sign","class":"OCA\\Libresign\\Handler\\Pkcs12Handler","type":"->"},{"file":"\/var\/www\/nextcloud\/apps\/libresign\/lib\/Controller\/SignFileController.php","line":129,"function":"sign","class":"OCA\\Libresign\\Service\\SignFileService","type":"->"},{"file":"\/var\/www\/nextcloud\/apps\/libresign\/lib\/Controller\/SignFileController.php","line":95,"function":"sign","class":"OCA\\Libresign\\Controller\\SignFileController","type":"->"},{"file":"\/var\/www\/nextcloud\/lib\/private\/AppFramework\/Http\/Dispatcher.php","line":208,"function":"signUsingUuid","class":"OCA\\Libresign\\Controller\\SignFileController","type":"->"},{"file":"\/var\/www\/nextcloud\/lib\/private\/AppFramework\/Http\/Dispatcher.php","line":114,"function":"executeController","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"\/var\/www\/nextcloud\/lib\/private\/AppFramework\/App.php","line":161,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"\/var\/www\/nextcloud\/lib\/private\/Route\/Router.php","line":302,"function":"main","class":"OC\\AppFramework\\App","type":"::"},{"file":"\/var\/www\/nextcloud\/ocs\/v1.php","line":43,"function":"match","class":"OC\\Route\\Router","type":"->"},{"file":"\/var\/www\/nextcloud\/ocs\/v2.php","line":7,"args":["\/var\/www\/nextcloud\/ocs\/v1.php"],"function":"require_once"}] POST /ocs/v2.php/apps/libresign/api/v1/sign/uuid/9e99a3a6-c111-4090-8b80-7dd41c630c5f von 2003:c1:9f04:6500:f329:f61d:e252:e99f von -- um 15.11.2024, 12:21:36 [libresign] Fehler: Error to sign PDF. ["FINE Default property file doesn't exists.","FINE Default property file doesn't exists.","INFO Checking input and output PDF paths.","INFO Getting key alias","INFO Used key alias: moritz busch","INFO Loading private key","INFO Getting certificate chain","INFO Opening input PDF file: \/tmp\/7b089a15366fcdc896a299330fbaf815.pdf","INFO Creating output PDF file: \/tmp\/7b089a15366fcdc896a299330fbaf815_signed.pdf","INFO Creating signature","SEVERE Problem occured","com.lowagie.text.DocumentException: Append mode requires a document without errors even if recovery was possible.","\tat com.lowagie.text.pdf.PdfStamperImp.(PdfStamperImp.java:123)","\tat com.lowagie.text.pdf.PdfStamper.(PdfStamper.java:130)","\tat com.lowagie.text.pdf.PdfStamper.createSignature(PdfStamper.java:707)","\tat net.sf.jsignpdf.SignerLogic.signFile(SignerLogic.java:204)","\tat net.sf.jsignpdf.Signer.signFiles(Signer.java:246)","\tat net.sf.jsignpdf.Signer.main(Signer.java:139)","","INFO Finished: Creating of signature failed."] POST /ocs/v2.php/apps/libresign/api/v1/sign/uuid/9e99a3a6-c111-4090-8b80-7dd41c630c5f von 2003:c1:9f04:6500:f329:f61d:e252:e99f von -- um 15.11.2024, 12:21:36

[libresign] Fehler: Error at JSignPdf side. LibreSign can not do nothing. Follow the error message: Error to sign PDF. ["FINE Default property file doesn't exists.","FINE Default property file doesn't exists.","INFO Checking input and output PDF paths.","INFO Getting key alias","INFO Used key alias: moritz busch","INFO Loading private key","INFO Getting certificate chain","INFO Opening input PDF file: /tmp/7b089a15366fcdc896a299330fbaf815.pdf","INFO Creating output PDF file: /tmp/7b089a15366fcdc896a299330fbaf815_signed.pdf","INFO Creating signature","SEVERE Problem occured","com.lowagie.text.DocumentException: Append mode requires a document without errors even if recovery was possible.","\tat com.lowagie.text.pdf.PdfStamperImp.(PdfStamperImp.java:123)","\tat com.lowagie.text.pdf.PdfStamper.(PdfStamper.java:130)","\tat com.lowagie.text.pdf.PdfStamper.createSignature(PdfStamper.java:707)","\tat net.sf.jsignpdf.SignerLogic.signFile(SignerLogic.java:204)","\tat net.sf.jsignpdf.Signer.signFiles(Signer.java:246)","\tat net.sf.jsignpdf.Signer.main(Signer.java:139)","","INFO Finished: Creating of signature failed."]
POST /ocs/v2.php/apps/libresign/api/v1/sign/uuid/9e99a3a6-c111-4090-8b80-7dd41c630c5f
von 2003:c1:9f04:6500:f329:f61d:e252:e99f von -- um 15.11.2024, 12:21:36

Describe the solution you'd like
Edit a document and then sign it.

[vitormattos]

Can you provide more details about what you mean by "editing pdf"? Perhaps step by step so I can reproduce it using screenshots or a screen recording.

It seems like a very specific scenario and from the message, it seems that somehow the PDF has something that is being considered corrupted.

Can you share this PDF with me? You can attach it to this issue. If it is not possible to attach it to the issue because it may contain sensitive data, you can send it to me by email or Telegram. My contacts are on my GitHub profile.

[moritz76]

Thanks for your quick reply!

By "edit pdf" I mean that when you open a PDF document in a web browser such as Firefox, you have the option to write, draw or insert an image:

It does not matter which pdf.

Here is what I see when I try to sign this edited PDF:

I have also attached a sample document.
Testdocument-1.pdf

[vitormattos]

@moritz76 Is this error occurring only after you edit the document? I made a test with your sample document with success.