Hello Zad. Over a month ago, I started a post concerning the building of a CAN API for Arduino Due. Since then, I've built a proto-shield and ran a couple of examples in my Due, accommodated from the ones under SAM3X-EK, but, like Massimo stated, there is a lot of peripheral stuff that needs to be remove and now, we have the help of the ATMEL engineer who wrote the ASF examples with the hope of publishing very soon a workable library and sketches in Github. Please, keep following the post and try to build your transceiver shield. And thanks for you offering to help. You and everybody are welcome to contribute and discuss!
Post:
http://arduino.cc/forum/index.php/topic,131096.0.html
Arduino Due CAN repository in Github:
https://github.com/arduino-libraries/arduino-due-can