Removing PDF usage restrictions

With qpdf:

$ qpdf --decrypt restricted-input.pdf unrestricted-output.pdf

You can probably use pdftk. Something like

pdftk in.pdf output out.pdf allow AllFeatures

should do the job.

If you've got ghostscript installed try simply:

gs -sPDFPassword=$PASS -q -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -sOutputFile=%stdout% -c .setpdfwrite -f locked.pdf > unlocked.pdf