opening, reading, writing to file from kernel

I need to change the data field in select outgoing TCP packets with information from a data file in user space. I think the easiest way to do this would be to replace the pointer to skb->data with a pointer to the applicable portion of my data file. But, I'm not clear on how to do this.

I'd prefer just to do a sys_open() or some other file open command to gain access to my data file.

Any ideas? I apologize, but, I am by no means a kernel level programmer. I'm just trying to get the kernel to do this one little thing.

Thanks in advance for any specific examples

Get 250 color business cards for FREE!
http://businesscards.lycos.com/vp/fastpath/