Hi Shashi,
you're on the right path.

- but in step 3. you should put placeholders in the 
  values /ByteRange and /Contents (e.g. zeros or whatever).

- after writing out the resulting PDF (step 4.) you should work
  only on these placeholders, you don't need iText 
  any more (you must not use it cause any further PDF reading 
  and writing reorganizes your PDF and the 
  calculated Byte ranges and signature aren't valid any more)

- then calculate the Byte Ranges and replace the placeholder
  for /ByteRange with the calculated values.

- then calculate the signature with Bouncycastle and replace
  its placeholder /Contents.

Now you can stream the result to a file.

BTW: you can use IBM PKCS-Jars from the IBM JDK, too. I found
them even more inuitive than BC. But don't ask me about 
license issues...

Regards,
Peter

> Hi,
>  
> I ma doing the following steps one by one please let me know where I am
> doing wrong.
>  
> I want to sign and encrypt an existing PDF document.
>  
> Here are the steps I follow.
>  
> 1. I open the document in PDF reader. 
> 2. I creat a new PDFwriter.
> 3. Do the copy of pages, Bookmars. and then add the signarue field to the
> PDF document
> 4. Close the PDF document and store as on temparary file.
> 5. Open this temporary file . compute the signature using Bouncy Castle.
> 6. Get the signed data.
> 7. Add the signed date to the content field of Signature PDF object.
> 8. Manipulate the byte range and close the file.
> 9. Now againa opne this temporary file using reader.
> 10. Pass thru the encrytor and stream it back as the final file.
>  
> But when I open the file in the acrobat reader, It adds a new page to the
> pdf document. 
> And then the document version is shown as 1 of 2, which means the document
> has been tampered with .
>  
> I suspect that the encryption is adding some bytes and hence the byte
> range that we specified during signing process got offset. 
> SO should we recalculate the byte range again and modify it after
> encrypting the file. Does this work? Is this the correct procedure./
> Any hep would be appreciated.
>  
> Thanks
> Shashi
> 
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