d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Correct and extend the description of the behaviour of rt_check().

Browse Source
This commit is contained in:
Luigi Rizzo 2004-04-24 23:34:56 +00:00
parent 3916ebe8f0
commit 769270223c
1 changed files with 27 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
sys/net/route.c
View File

@ -1207,17 +1207,37 @@ rtinit(struct ifaddr *ifa, int cmd, int flags)
}
/*
* Validate the route rt0 to the specified destination. If the
* route is marked down try to find a new route. If the route
* rt_check() is invoked on each layer 2 output path, prior to
* encapsulating outbound packets.
*
* The function is mostly used to find a routing entry for the gateway,
* which in some protocol families could also point to the link-level
* address for the gateway itself (the side effect of revalidating the
* route to the destination is rather pointless at this stage, we did it
* already a moment before in the pr_output() routine to locate the ifp
* and gateway to use).
*
* When we remove the layer-3 to layer-2 mapping tables from the
* routing table, this function can be removed.
*
* === On input ===
* *dst is the address of the NEXT HOP (which coincides with the
* final destination if directly reachable);
* *lrt0 points to the cached route to the final destination;
* *lrt is not meaningful;
*
* === Operation ===
* If the route is marked down try to find a new route. If the route
* to the gateway is gone, try to setup a new route. Otherwise,
* if the route is marked for packets to be rejected, enforce that.
*
* On return lrt contains the route to the destination and lrt0
* contains the route to the next hop. Their values are meaningul
* ONLY if no error is returned.
* === On return ===
* *dst is unchanged;
* *lrt0 points to the (possibly new) route to the final destination
* (NOTE: different meaning from what it was on input)
* *lrt points to the route to the next hop
*
* This routine is invoked on each layer 2 output path, prior to
* encapsulating outbound packets.
* Their values are meaningul ONLY if no error is returned.
*/
int
rt_check(struct rtentry **lrt, struct rtentry **lrt0, struct sockaddr *dst)