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path: root/include/net/ip_fib.h
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2015-11-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Minor overlapping changes in net/ipv4/ipmr.c, in 'net' we were fixing the "BH-ness" of the counter bumps whilst in 'net-next' the functions were modified to take an explicit 'net' parameter. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-01ipv4: fix to not remove local route on link downJulian Anastasov
When fib_netdev_event calls fib_disable_ip on NETDEV_DOWN event we should not delete the local routes if the local address is still present. The confusion comes from the fact that both fib_netdev_event and fib_inetaddr_event use the NETDEV_DOWN constant. Fix it by returning back the variable 'force'. Steps to reproduce: modprobe dummy ifconfig dummy0 192.168.168.1 up ifconfig dummy0 down ip route list table local | grep dummy | grep host local 192.168.168.1 dev dummy0 proto kernel scope host src 192.168.168.1 Fixes: 8a3d03166f19 ("net: track link-status of ipv4 nexthops") Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-07net: Refactor path selection in __ip_route_output_key_hashDavid Ahern
VRF device needs the same path selection following lookup to set source address. Rather than duplicating code, move existing code into a function that is exported to modules. Code move only; no functional change. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-05ipv4: L3 hash-based multipathPeter Nørlund
Replaces the per-packet multipath with a hash-based multipath using source and destination address. Signed-off-by: Peter Nørlund <pch@ordbogen.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-20net: Fix behaviour of unreachable, blackhole and prohibit routesNikola Forró
Man page of ip-route(8) says following about route types: unreachable - these destinations are unreachable. Packets are dis‐ carded and the ICMP message host unreachable is generated. The local senders get an EHOSTUNREACH error. blackhole - these destinations are unreachable. Packets are dis‐ carded silently. The local senders get an EINVAL error. prohibit - these destinations are unreachable. Packets are discarded and the ICMP message communication administratively prohibited is generated. The local senders get an EACCES error. In the inet6 address family, this was correct, except the local senders got ENETUNREACH error instead of EHOSTUNREACH in case of unreachable route. In the inet address family, all three route types generated ICMP message net unreachable, and the local senders got ENETUNREACH error. In both address families all three route types now behave consistently with documentation. Signed-off-by: Nikola Forró <nforro@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: arch/s390/net/bpf_jit_comp.c drivers/net/ethernet/ti/netcp_ethss.c net/bridge/br_multicast.c net/ipv4/ip_fragment.c All four conflicts were cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-24ipv4: consider TOS in fib_select_defaultJulian Anastasov
fib_select_default considers alternative routes only when res->fi is for the first alias in res->fa_head. In the common case this can happen only when the initial lookup matches the first alias with highest TOS value. This prevents the alternative routes to require specific TOS. This patch solves the problem as follows: - routes that require specific TOS should be returned by fib_select_default only when TOS matches, as already done in fib_table_lookup. This rule implies that depending on the TOS we can have many different lists of alternative gateways and we have to keep the last used gateway (fa_default) in first alias for the TOS instead of using single tb_default value. - as the aliases are ordered by many keys (TOS desc, fib_priority asc), we restrict the possible results to routes with matching TOS and lowest metric (fib_priority) and routes that match any TOS, again with lowest metric. For example, packet with TOS 8 can not use gw3 (not lowest metric), gw4 (different TOS) and gw6 (not lowest metric), all other gateways can be used: tos 8 via gw1 metric 2 <--- res->fa_head and res->fi tos 8 via gw2 metric 2 tos 8 via gw3 metric 3 tos 4 via gw4 tos 0 via gw5 tos 0 via gw6 metric 1 Reported-by: Hagen Paul Pfeifer <hagen@jauu.net> Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21ipv4: support for fib route lwtunnel encap attributesRoopa Prabhu
This patch adds support in ipv4 fib functions to parse user provided encap attributes and attach encap state data to fib_nh and rtable. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24net: ipv4 sysctl option to ignore routes when nexthop link is downAndy Gospodarek
This feature is only enabled with the new per-interface or ipv4 global sysctls called 'ignore_routes_with_linkdown'. net.ipv4.conf.all.ignore_routes_with_linkdown = 0 net.ipv4.conf.default.ignore_routes_with_linkdown = 0 net.ipv4.conf.lo.ignore_routes_with_linkdown = 0 ... When the above sysctls are set, will report to userspace that a route is dead and will no longer resolve to this nexthop when performing a fib lookup. This will signal to userspace that the route will not be selected. The signalling of a RTNH_F_DEAD is only passed to userspace if the sysctl is enabled and link is down. This was done as without it the netlink listeners would have no idea whether or not a nexthop would be selected. The kernel only sets RTNH_F_DEAD internally if the interface has IFF_UP cleared. With the new sysctl set, the following behavior can be observed (interface p8p1 is link-down): default via 10.0.5.2 dev p9p1 10.0.5.0/24 dev p9p1 proto kernel scope link src 10.0.5.15 70.0.0.0/24 dev p7p1 proto kernel scope link src 70.0.0.1 80.0.0.0/24 dev p8p1 proto kernel scope link src 80.0.0.1 dead linkdown 90.0.0.0/24 via 80.0.0.2 dev p8p1 metric 1 dead linkdown 90.0.0.0/24 via 70.0.0.2 dev p7p1 metric 2 90.0.0.1 via 70.0.0.2 dev p7p1 src 70.0.0.1 cache local 80.0.0.1 dev lo src 80.0.0.1 cache <local> 80.0.0.2 via 10.0.5.2 dev p9p1 src 10.0.5.15 cache While the route does remain in the table (so it can be modified if needed rather than being wiped away as it would be if IFF_UP was cleared), the proper next-hop is chosen automatically when the link is down. Now interface p8p1 is linked-up: default via 10.0.5.2 dev p9p1 10.0.5.0/24 dev p9p1 proto kernel scope link src 10.0.5.15 70.0.0.0/24 dev p7p1 proto kernel scope link src 70.0.0.1 80.0.0.0/24 dev p8p1 proto kernel scope link src 80.0.0.1 90.0.0.0/24 via 80.0.0.2 dev p8p1 metric 1 90.0.0.0/24 via 70.0.0.2 dev p7p1 metric 2 192.168.56.0/24 dev p2p1 proto kernel scope link src 192.168.56.2 90.0.0.1 via 80.0.0.2 dev p8p1 src 80.0.0.1 cache local 80.0.0.1 dev lo src 80.0.0.1 cache <local> 80.0.0.2 dev p8p1 src 80.0.0.1 cache and the output changes to what one would expect. If the sysctl is not set, the following output would be expected when p8p1 is down: default via 10.0.5.2 dev p9p1 10.0.5.0/24 dev p9p1 proto kernel scope link src 10.0.5.15 70.0.0.0/24 dev p7p1 proto kernel scope link src 70.0.0.1 80.0.0.0/24 dev p8p1 proto kernel scope link src 80.0.0.1 linkdown 90.0.0.0/24 via 80.0.0.2 dev p8p1 metric 1 linkdown 90.0.0.0/24 via 70.0.0.2 dev p7p1 metric 2 Since the dead flag does not appear, there should be no expectation that the kernel would skip using this route due to link being down. v2: Split kernel changes into 2 patches, this actually makes a behavioral change if the sysctl is set. Also took suggestion from Alex to simplify code by only checking sysctl during fib lookup and suggestion from Scott to add a per-interface sysctl. v3: Code clean-ups to make it more readable and efficient as well as a reverse path check fix. v4: Drop binary sysctl v5: Whitespace fixups from Dave v6: Style changes from Dave and checkpatch suggestions v7: One more checkpatch fixup Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com> Signed-off-by: Dinesh Dutt <ddutt@cumulusnetworks.com> Acked-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24net: track link-status of ipv4 nexthopsAndy Gospodarek
Add a fib flag called RTNH_F_LINKDOWN to any ipv4 nexthops that are reachable via an interface where carrier is off. No action is taken, but additional flags are passed to userspace to indicate carrier status. This also includes a cleanup to fib_disable_ip to more clearly indicate what event made the function call to replace the more cryptic force option previously used. v2: Split out kernel functionality into 2 patches, this patch simply sets and clears new nexthop flag RTNH_F_LINKDOWN. v3: Cleanups suggested by Alex as well as a bug noticed in fib_sync_down_dev and fib_sync_up when multipath was not enabled. v5: Whitespace and variable declaration fixups suggested by Dave. v6: Style fixups noticed by Dave; ran checkpatch to be sure I got them all. Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com> Signed-off-by: Dinesh Dutt <ddutt@cumulusnetworks.com> Acked-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-11ipv4: FIB Local/MAIN table collapseAlexander Duyck
This patch is meant to collapse local and main into one by converting tb_data from an array to a pointer. Doing this allows us to point the local table into the main while maintaining the same variables in the table. As such the tb_data was converted from an array to a pointer, and a new array called data is added in order to still provide an object for tb_data to point to. In order to track the origin of the fib aliases a tb_id value was added in a hole that existed on 64b systems. Using this we can also reverse the merge in the event that custom FIB rules are enabled. With this patch I am seeing an improvement of 20ns to 30ns for routing lookups as long as custom rules are not enabled, with custom rules enabled we fall back to split tables and the original behavior. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06switchdev: don't support custom ip rules, for nowScott Feldman
Keep switchdev FIB offload model simple for now and don't allow custom ip rules. Signed-off-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04fib_trie: Make fib_table rcu safeAlexander Duyck
The fib_table was wrapped in several places with an rcu_read_lock/rcu_read_unlock however after looking over the code I found several spots where the tables were being accessed as just standard pointers without any protections. This change fixes that so that all of the proper protections are in place when accessing the table to take RCU replacement or removal of the table into account. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-27fib_trie: Convert fib_alias to hlist from listAlexander Duyck
There isn't any advantage to having it as a list and by making it an hlist we make the fib_alias more compatible with the list_info in terms of the type of list used. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Push rcu_read_lock/unlock to callersAlexander Duyck
This change is to start cleaning up some of the rcu_read_lock/unlock handling. I realized while reviewing the code there are several spots that I don't believe are being handled correctly or are masking warnings by locally calling rcu_read_lock/unlock instead of calling them at the correct level. A common example is a call to fib_get_table followed by fib_table_lookup. The rcu_read_lock/unlock ought to wrap both but there are several spots where they were not wrapped. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-08fib_trie: Fix /proc/net/fib_trie when CONFIG_IP_MULTIPLE_TABLES is not definedAlexander Duyck
In recent testing I had disabled CONFIG_IP_MULTIPLE_TABLES and as a result when I ran "cat /proc/net/fib_trie" the main trie was displayed multiple times. I found that the problem line of code was in the function fib_trie_seq_next. Specifically the line below caused the indexes to go in the opposite direction of our traversal: h = tb->tb_id & (FIB_TABLE_HASHSZ - 1); This issue was that the RT tables are defined such that RT_TABLE_LOCAL is ID 255, while it is located at TABLE_LOCAL_INDEX of 0, and RT_TABLE_MAIN is 254 with a TABLE_MAIN_INDEX of 1. This means that the above line will return 1 for the local table and 0 for main. The result is that fib_trie_seq_next will return NULL at the end of the local table, fib_trie_seq_start will return the start of the main table, and then fib_trie_seq_next will loop on main forever as h will always return 0. The fix for this is to reverse the ordering of the two tables. It has the advantage of making it so that the tables now print in the same order regardless of if multiple tables are enabled or not. In order to make the definition consistent with the multiple tables case I simply masked the to RT_TABLE_XXX values by (FIB_TABLE_HASHSZ - 1). This way the two table layouts should always stay consistent. Fixes: 93456b6 ("[IPV4]: Unify access to the routing tables") Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-05ipv4: harden fnhe_hashfun()Eric Dumazet
Lets make this hash function a bit secure, as ICMP attacks are still in the wild. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-05ipv4: fix a race in update_or_create_fnhe()Eric Dumazet
nh_exceptions is effectively used under rcu, but lacks proper barriers. Between kzalloc() and setting of nh->nh_exceptions(), we need a proper memory barrier. Signed-off-by: Eric Dumazet <edumazet@google.com> Fixes: 4895c771c7f00 ("ipv4: Add FIB nexthop exceptions.") Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-21ip*.h: Remove extern from function prototypesJoe Perches
There are a mix of function prototypes with and without extern in the kernel sources. Standardize on not using extern for function prototypes. Function prototypes don't need to be written with extern. extern is assumed by the compiler. Its use is as unnecessary as using auto to declare automatic/local variables in a block. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-02ipv4: remove fib_update_nh_saddrs() declaration.Rami Rosen
This patch removes the fib_update_nh_saddrs() declaration from include/net/ip_fib.h, as the fib_update_nh_saddrs() method was removed in coomit 436c3b6 ("ipv4: Invalidate nexthop cache nh_saddr more correctly"). Signed-off-by: Rami Rosen <ramirose@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-28ipv4: use next hop exceptions also for input routesTimo Teräs
Commit d2d68ba9 (ipv4: Cache input routes in fib_info nexthops) assmued that "locally destined, and routed packets, never trigger PMTU events or redirects that will be processed by us". However, it seems that tunnel devices do trigger PMTU events in certain cases. At least ip_gre, ip6_gre, sit, and ipip do use the inner flow's skb_dst(skb)->ops->update_pmtu to propage mtu information from the outer flows. These can cause the inner flow mtu to be decreased. If next hop exceptions are not consulted for pmtu, IP fragmentation will not be done properly for these routes. It also seems that we really need to have the PMTU information always for netfilter TCPMSS clamp-to-pmtu feature to work properly. So for the time being, cache separate copies of input routes for each next hop exception. Signed-off-by: Timo Teräs <timo.teras@iki.fi> Reviewed-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-03ipv4: use separate genid for next hop exceptionsTimo Teräs
commit 13d82bf5 (ipv4: Fix flushing of cached routing informations) added the support to flush learned pmtu information. However, using rt_genid is quite heavy as it is bumped on route add/change and multicast events amongst other places. These can happen quite often, especially if using dynamic routing protocols. While this is ok with routes (as they are just recreated locally), the pmtu information is learned from remote systems and the icmp notification can come with long delays. It is worthy to have separate genid to avoid excessive pmtu resets. Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Timo Teräs <timo.teras@iki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-13ipv4: fix definition of FIB_TABLE_HASHSZDenis V. Lunev
a long time ago by the commit commit 93456b6d7753def8760b423ac6b986eb9d5a4a95 Author: Denis V. Lunev <den@openvz.org> Date: Thu Jan 10 03:23:38 2008 -0800 [IPV4]: Unify access to the routing tables. the defenition of FIB_HASH_TABLE size has obtained wrong dependency: it should depend upon CONFIG_IP_MULTIPLE_TABLES (as was in the original code) but it was depended from CONFIG_IP_ROUTE_MULTIPATH This patch returns the situation to the original state. The problem was spotted by Tingwei Liu. Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Tingwei Liu <tingw.liu@gmail.com> CC: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-04ipv4: add a fib_type to fib_infoEric Dumazet
commit d2d68ba9fe8 (ipv4: Cache input routes in fib_info nexthops.) introduced a regression for forwarding. This was hard to reproduce but the symptom was that packets were delivered to local host instead of being forwarded. David suggested to add fib_type to fib_info so that we dont inadvertently share same fib_info for different purposes. With help from Julian Anastasov who provided very helpful hints, reproduced here : <quote> Can it be a problem related to fib_info reuse from different routes. For example, when local IP address is created for subnet we have: broadcast 192.168.0.255 dev DEV proto kernel scope link src 192.168.0.1 192.168.0.0/24 dev DEV proto kernel scope link src 192.168.0.1 local 192.168.0.1 dev DEV proto kernel scope host src 192.168.0.1 The "dev DEV proto kernel scope link src 192.168.0.1" is a reused fib_info structure where we put cached routes. The result can be same fib_info for 192.168.0.255 and 192.168.0.0/24. RTN_BROADCAST is cached only for input routes. Incoming broadcast to 192.168.0.255 can be cached and can cause problems for traffic forwarded to 192.168.0.0/24. So, this patch should solve the problem because it separates the broadcast from unicast traffic. And the ip_route_input_slow caching will work for local and broadcast input routes (above routes 1 and 3) just because they differ in scope and use different fib_info. </quote> Many thanks to Chris Clayton for his patience and help. Reported-by: Chris Clayton <chris2553@googlemail.com> Bisected-by: Chris Clayton <chris2553@googlemail.com> Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Julian Anastasov <ja@ssi.bg> Tested-by: Chris Clayton <chris2553@googlemail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31ipv4: Cache routes in nexthop exception entries.David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31ipv4: percpu nh_rth_output cacheEric Dumazet
Input path is mostly run under RCU and doesnt touch dst refcnt But output path on forwarding or UDP workloads hits badly dst refcount, and we have lot of false sharing, for example in ipv4_mtu() when reading rt->rt_pmtu Using a percpu cache for nh_rth_output gives a nice performance increase at a small cost. 24 udpflood test on my 24 cpu machine (dummy0 output device) (each process sends 1.000.000 udp frames, 24 processes are started) before : 5.24 s after : 2.06 s For reference, time on linux-3.5 : 6.60 s Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31ipv4: Restore old dst_free() behavior.Eric Dumazet
commit 404e0a8b6a55 (net: ipv4: fix RCU races on dst refcounts) tried to solve a race but added a problem at device/fib dismantle time : We really want to call dst_free() as soon as possible, even if sockets still have dst in their cache. dst_release() calls in free_fib_info_rcu() are not welcomed. Root of the problem was that now we also cache output routes (in nh_rth_output), we must use call_rcu() instead of call_rcu_bh() in rt_free(), because output route lookups are done in process context. Based on feedback and initial patch from David Miller (adding another call_rcu_bh() call in fib, but it appears it was not the right fix) I left the inet_sk_rx_dst_set() helper and added __rcu attributes to nh_rth_output and nh_rth_input to better document what is going on in this code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20ipv4: Cache input routes in fib_info nexthops.David S. Miller
Caching input routes is slightly simpler than output routes, since we don't need to be concerned with nexthop exceptions. (locally destined, and routed packets, never trigger PMTU events or redirects that will be processed by us). However, we have to elide caching for the DIRECTSRC and non-zero itag cases. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20ipv4: Cache output routes in fib_info nexthops.David S. Miller
If we have an output route that lacks nexthop exceptions, we can cache it in the FIB info nexthop. Such routes will have DST_HOST cleared because such routes refer to a family of destinations, rather than just one. The sequence of the handling of exceptions during route lookup is adjusted to make the logic work properly. Before we allocate the route, we lookup the exception. Then we know if we will cache this route or not, and therefore whether DST_HOST should be set on the allocated route. Then we use DST_HOST to key off whether we should store the resulting route, during rt_set_nexthop(), in the FIB nexthop cache. With help from Eric Dumazet. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-19ipv4: use seqlock for nh_exceptionsJulian Anastasov
Use global seqlock for the nh_exceptions. Call fnhe_oldest with the right hash chain. Correct the diff value for dst_set_expires. v2: after suggestions from Eric Dumazet: * get rid of spin lock fnhe_lock, rearrange update_or_create_fnhe * continue daddr search in rt_bind_exception v3: * remove the daddr check before seqlock in rt_bind_exception * restart lookup in rt_bind_exception on detected seqlock change, as suggested by David Miller Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-17ipv4: Add FIB nexthop exceptions.David S. Miller
In a regime where we have subnetted route entries, we need a way to store persistent storage about destination specific learned values such as redirects and PMTU values. This is implemented here via nexthop exceptions. The initial implementation is a 2048 entry hash table with relaiming starting at chain length 5. A more sophisticated scheme can be devised if that proves necessary. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-13ipv4: Don't store a rule pointer in fib_result.David S. Miller
We only use it to fetch the rule's tclassid, so just store the tclassid there instead. This also decreases the size of fib_result by a full 8 bytes on 64-bit. On 32-bits it's a wash. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-12ipv4: Remove tb_peers from fib_table.David S. Miller
No longer used. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-10ipv4: Fix crashes in fib_rules_tclass().David S. Miller
All paths assume, when CONFIG_IP_MULTIPLE_TABLES is enabled, that any successful call to fib_lookup() will initialize the fib_result->r value to something. We violated that expectation in the new fib_lookup() fast path. Reported-by: Or Gerlitz <ogerlitz@mellanox.com> Tested-by: Eric Dumazet <eric.dumazet@gmail.com> Tested-by: Greg Rose <gregory.v.rose@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-05ipv4: Avoid overhead when no custom FIB rules are installed.David S. Miller
If the user hasn't actually installed any custom rules, or fiddled with the default ones, don't go through the whole FIB rules layer. It's just pure overhead. Instead do what we do with CONFIG_IP_MULTIPLE_TABLES disabled, check the individual tables by hand, one by one. Also, move fib_num_tclassid_users into the ipv4 network namespace. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-29ipv4: Elide fib_validate_source() completely when possible.David S. Miller
If rpfilter is off (or the SKB has an IPSEC path) and there are not tclassid users, we don't have to do anything at all when fib_validate_source() is invoked besides setting the itag to zero. We monitor tclassid uses with a counter (modified only under RTNL and marked __read_mostly) and we protect the fib_validate_source() real work with a test against this counter and whether rpfilter is to be done. Having a way to know whether we need no tclassid processing or not also opens the door for future optimized rpfilter algorithms that do not perform full FIB lookups. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-28ipv4: Adjust in_dev handling in fib_validate_source()David S. Miller
Checking for in_dev being NULL is pointless. In fact, all of our callers have in_dev precomputed already, so just pass it in and remove the NULL checking. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-28ipv4: Kill rt->rt_spec_dst, no longer used.David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-28ipv4: Create and use fib_compute_spec_dst() helper.David S. Miller
The specific destination is the host we direct unicast replies to. Usually this is the original packet source address, but if we are responding to a multicast or broadcast packet we have to use something different. Specifically we must use the source address we would use if we were to send a packet to the unicast source of the original packet. The routing cache precomputes this value, but we want to remove that precomputation because it creates a hard dependency on the expensive rpfilter source address validation which we'd like to make cheaper. There are only three places where this matters: 1) ICMP replies. 2) pktinfo CMSG 3) IP options Now there will be no real users of rt->rt_spec_dst and we can simply remove it altogether. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-11inet: Add inetpeer tree roots to the FIB tables.David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15net: cleanup unsigned to unsigned intEric Dumazet
Use of "unsigned int" is preferred to bare "unsigned" in net tree. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-14ipv4: Call fib_select_default() only when actually necessary.David S. Miller
fib_select_default() is a complete NOP, and completely pointless to invoke, when we have no more than 1 default route installed. And this is far and away the common case. So remember how many prefixlen==0 routes we have in the routing table, and elide the call when we have no more than one of those. This cuts output route creation time by 157 cycles on Niagara2+. In order to add the new int to fib_table, we have to correct the type of ->tb_data[] to unsigned long, otherwise the private area will be unaligned on 64-bit systems. Signed-off-by: David S. Miller <davem@davemloft.net> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
2011-04-10fib_validate_source(): pass sk_buff instead of markMichael Smith
This makes sk_buff available for other use in fib_validate_source(). Signed-off-by: Michael Smith <msmith@cbnco.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-24ipv4: Fix nexthop caching wrt. scoping.David S. Miller
Move the scope value out of the fib alias entries and into fib_info, so that we always use the correct scope when recomputing the nexthop cached source address. Reported-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-24ipv4: Invalidate nexthop cache nh_saddr more correctly.David S. Miller
Any operation that: 1) Brings up an interface 2) Adds an IP address to an interface 3) Deletes an IP address from an interface can potentially invalidate the nh_saddr value, requiring it to be recomputed. Perform the recomputation lazily using a generation ID. Reported-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-12ipv4: Pass ipv4 flow objects into fib_lookup() paths.David S. Miller
To start doing these conversions, we need to add some temporary flow4_* macros which will eventually go away when all the protocol code paths are changed to work on AF specific flowi objects. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-10ipv4: Kill flowi arg to fib_select_multipath()David S. Miller
Completely unused. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-08ipv4: Fix scope value used in route src-address caching.David S. Miller
We have to use cfg->fc_scope not the final nh_scope value. Reported-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-07ipv4: Cache source address in nexthop entries.David S. Miller
When doing output route lookups, we have to select the source address if the user has not specified an explicit one. First, if the route has an explicit preferred source address specified, then we use that. Otherwise we search the route's outgoing interface for a suitable address. This search can be precomputed and cached at route insertion time. The only missing part is that we have to refresh this precomputed value any time addresses are added or removed from the interface, and this is accomplished by fib_update_nh_saddrs(). Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-17ipv4: Use const'ify fib_result deep in the route call chains.David S. Miller
The only troublesome bit here is __mkroute_output which wants to override res->fi and res->type, compute those in local variables instead. Signed-off-by: David S. Miller <davem@davemloft.net>