/*
* Create the "control" list for this pcb.
*
* The routine will be called from upper layer handlers like tcp6_input().
* Thus the routine assumes that the caller (tcp6_input) have already
* called IP6_EXTHDR_CHECK() and all the extension headers are located in the
* very first mbuf on the mbuf chain.
* We may want to add some infinite loop prevention or sanity checks for safety.
* (This applies only when you are using KAME mbuf chain restriction, i.e.
* you are using IP6_EXTHDR_CHECK() not m_pulldown())
*/