Possible xRef fixing on signed document

[kibitzerCZ]

Product:
PDFNet.dll
Product Version:
PDFNetDotNet4, version 9.1.0
Please give a brief summary of your issue:
Possible xRef fixing on signed document

Please describe your issue and provide steps to reproduce it:
I have a PDF document that contains 6 signatures (one signature and 5 time stamps to be precise). After I load that PDF to PDFViewCtrl, it declares to have been modified (IsModified returns true). However HasRepairedXRef returns false. When I save this document without any changes made by me (using SaveOptions=0) its signatures are all breached.

I guess some fixes or optimization happen inside PDFViewCtrl during PDF document loading, but it should not be done when the document is signed, or there should be an option for developer to disable this behavior.

Could you please put some light on what’s happening and tell if there is a way to workaround this behavior (to save document without breaching the signatures)?

Please provide a link to a minimal sample where the issue is reproducible:

PDFnet_sample.zip

[system]

Hello, I’m Ron, an automated tech support bot

While you wait for one of our customer support representatives to get back to you, please check out some of these documentation pages:

Guides:

• Add Long-Term Validation (LTV) information for a signature on Cross-Platform (Core)
• Filling PDF form fields on Cross-Platform (Core) - About filling form fields
• Serialization / Saving PDFs on Cross-Platform (Core) - About saving a document
• Encrypting & securing PDFs on Cross-Platform (Core) - About securing a document with encryption

APIs:

• PDFCompat.PDFViewCtrl - public static void RotateClockwise (long impl)
• Class PDFRasterizer
• PDFViewCtrl - public static void setViewerCache (SDFDoc document, int max_cache_size, boolean on_disk)

Forums:

• Detecting and fixing non-conformant PDF files
• How do I get the name of the default printer selected in PDFViewCtrl.Print() ?
• What is the maximum time PDFTRON sdk running, and About signature

[Ryan]

When I save this document without any changes made by me
tell if there is a way to workaround this behavior (to save document without breaching the signatures)?

Yes, just copy the original file data.

If you are not making any changes to the file then why are you saving it? If you need an extra copy then copying the original data would be ideal.

[kibitzerCZ]

Ryan, this scenario comes from a larger application, that sends the document to server for further processing. Before sending to server, I save the document as it could have been changed by user performing some other action previously. For changes detection I use IsModified function, which in case of the respective document returns true even if user did not perform any action. And when I save it, the signatures got breached.

[Ryan]

Thank you for clarifying your situation. We are reviewing and I will update you once I know more.

[kibitzerCZ]

Hi Ryan, it has been more than three weeks, is there any progress with this issue?

[Ryan]

I just wanted to let you know that work has been in progress on this issue, and will be corrected soon. Once I get a more confident time estimate I will update.