Generate PDF with digital signature

Question

Is it possible to generate PDF file in PHP with digital signature? An open-source solution is preferred.

Answer 1

The VersyPDF PHP library (Commercial) will also sign documents

It is also possible to use the open source iText java library and a PHP-Java bridge to allow communication. See the iText FAQ on this

iText can sign documents by self signing, veriSign plug-in or windows Certificate Security. When I've used it in the past on Java projects, signing documents is just coping examples and usually takes under a hundred lines. The hardest bit is getting the right certificates to sign it with.