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2017-08-03net: fib_rules: Implement notification logic in coreIdo Schimmel1-12/+12
Unlike the routing tables, the FIB rules share a common core, so instead of replicating the same logic for each address family we can simply dump the rules and send notifications from the core itself. To protect the integrity of the dump, a rules-specific sequence counter is added for each address family and incremented whenever a rule is added or deleted (under RTNL). Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-03net: core: Make the FIB notification chain genericIdo Schimmel1-22/+8
The FIB notification chain is currently soley used by IPv4 code. However, we're going to introduce IPv6 FIB offload support, which requires these notification as well. As explained in commit c3852ef7f2f8 ("ipv4: fib: Replay events when registering FIB notifier"), upon registration to the chain, the callee receives a full dump of the FIB tables and rules by traversing all the net namespaces. The integrity of the dump is ensured by a per-namespace sequence counter that is incremented whenever a change to the tables or rules occurs. In order to allow more address families to use the chain, each family is expected to register its fib_notifier_ops in its pernet init. These operations allow the common code to read the family's sequence counter as well as dump its tables and rules in the given net namespace. Additionally, a 'family' parameter is added to sent notifications, so that listeners could distinguish between the different families. Implement the common code that allows listeners to register to the chain and for address families to register their fib_notifier_ops. Subsequent patches will implement these operations in IPv6. In the future, ipmr and ip6mr will be extended to provide these notifications as well. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-02ipv4: fib: Remove unused functionsIdo Schimmel1-13/+0
Previous patches converted users of these functions to provide offload indication using the nexthop's flags instead of the FIB info's. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-04net, ipv4: convert fib_info.fib_clntref from atomic_t to refcount_tReshetova, Elena1-3/+4
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-30net: ipv4: Add extack message for invalid prefix or lengthDavid Ahern1-1/+2
Add extack error message for invalid prefix length and invalid prefix. Example of the latter is a route spec containing 172.16.100.1/24, where the /24 mask means the lower 8-bits should be 0. Amazing how easy that one is to overlook when an EINVAL is returned. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-5/+5
Overlapping changes in drivers/net/phy/marvell.c, bug fix in 'net' restricting a HW workaround alongside cleanups in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-26ipv4: add reference counting to metricsEric Dumazet1-5/+5
Andrey Konovalov reported crashes in ipv4_mtu() I could reproduce the issue with KASAN kernels, between 10.246.7.151 and 10.246.7.152 : 1) 20 concurrent netperf -t TCP_RR -H 10.246.7.152 -l 1000 & 2) At the same time run following loop : while : do ip ro add 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500 ip ro del 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500 done Cong Wang attempted to add back rt->fi in commit 82486aa6f1b9 ("ipv4: restore rt->fi for reference counting") but this proved to add some issues that were complex to solve. Instead, I suggested to add a refcount to the metrics themselves, being a standalone object (in particular, no reference to other objects) I tried to make this patch as small as possible to ease its backport, instead of being super clean. Note that we believe that only ipv4 dst need to take care of the metric refcount. But if this is wrong, this patch adds the basic infrastructure to extend this to other families. Many thanks to Julian Anastasov for reviewing this patch, and Cong Wang for his efforts on this problem. Fixes: 2860583fe840 ("ipv4: Kill rt->fi") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Julian Anastasov <ja@ssi.bg> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-26net: ipv4: Save trie prefix to fib lookup resultDavid Ahern1-0/+1
Prefix is needed for returning matching route spec on get route request. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-22net: ipv4: Plumb extack through route add functionsDavid Ahern1-1/+2
Plumb extack argument down to route add functions. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-21net: ipv4: add support for ECMP hash policy choiceNikolay Aleksandrov1-9/+5
This patch adds support for ECMP hash policy choice via a new sysctl called fib_multipath_hash_policy and also adds support for L4 hashes. The current values for fib_multipath_hash_policy are: 0 - layer 3 (default) 1 - layer 4 If there's an skb hash already set and it matches the chosen policy then it will be used instead of being calculated (currently only for L4). In L3 mode we always calculate the hash due to the ICMP error special case, the flow dissector's field consistentification should handle the address order thus we can remove the address reversals. If the skb is provided we always use it for the hash calculation, otherwise we fallback to fl4, that is if skb is NULL fl4 has to be set. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-16ipv4: fib_rules: Add notifier info to FIB rules notificationsIdo Schimmel1-0/+5
Whenever a FIB rule is added or removed, a notification is sent in the FIB notification chain. However, listeners don't have a way to tell which rule was added or removed. This is problematic as we would like to give listeners the ability to decide which action to execute based on the notified rule. Specifically, offloading drivers should be able to determine if they support the reflection of the notified FIB rule and flush their LPM tables in case they don't. Do that by adding a notifier info to these notifications and embed the common FIB rule struct in it. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Acked-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-16ipv4: fib_rules: Check if rule is a default ruleIdo Schimmel1-0/+7
Currently, when non-default (custom) FIB rules are used, devices capable of layer 3 offloading flush their tables and let the kernel do the forwarding instead. When these devices' drivers are loaded they register to the FIB notification chain, which lets them know about the existence of any custom FIB rules. This is done by sending a RULE_ADD notification based on the value of 'net->ipv4.fib_has_custom_rules'. This approach is problematic when VRF offload is taken into account, as upon the creation of the first VRF netdev, a l3mdev rule is programmed to direct skbs to the VRF's table. Instead of merely reading the above value and sending a single RULE_ADD notification, we should iterate over all the FIB rules and send a detailed notification for each, thereby allowing offloading drivers to sanitize the rules they don't support and potentially flush their tables. While l3mdev rules are uniquely marked, the default rules are not. Therefore, when they are being notified they might invoke offloading drivers to unnecessarily flush their tables. Solve this by adding an helper to check if a FIB rule is a default rule. Namely, its selector should match all packets and its action should point to the local, main or default tables. As noted by David Ahern, uniquely marking the default rules is insufficient. When using VRFs, it's common to avoid false hits by moving the rule for the local table to just before the main table: Default configuration: $ ip rule show 0: from all lookup local 32766: from all lookup main 32767: from all lookup default Common configuration with VRFs: $ ip rule show 1000: from all lookup [l3mdev-table] 32765: from all lookup local 32766: from all lookup main 32767: from all lookup default Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-10ipv4: fib: Remove redundant argumentIdo Schimmel1-6/+3
We always pass the same event type to fib_notify() and fib_rules_notify(), so we can safely drop this argument. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-10ipv4: fib: Move FIB notification code to a separate fileIdo Schimmel1-0/+15
Most of the code concerned with the FIB notification chain currently resides in fib_trie.c, but this isn't really appropriate, as the FIB notification chain is also used for FIB rules. Therefore, it makes sense to move the common FIB notification code to a separate file and have it export the relevant functions, which can be invoked by its different users (e.g., fib_trie.c, fib_rules.c). Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-10ipv4: fib: Add events for FIB replace and appendIdo Schimmel1-1/+2
The FIB notification chain currently uses the NLM_F_{REPLACE,APPEND} flags to signal routes being replaced or appended. Instead of using netlink flags for in-kernel notifications we can simply introduce two new events in the FIB notification chain. This has the added advantage of making the API cleaner, thereby making it clear that these events should be supported by listeners of the notification chain. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> CC: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-08ipv4: fib: Notify about nexthop status changesIdo Schimmel1-0/+7
When a multipath route is hit the kernel doesn't consider nexthops that are DEAD or LINKDOWN when IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN is set. Devices that offload multipath routes need to be made aware of nexthop status changes. Otherwise, the device will keep forwarding packets to non-functional nexthops. Add the FIB_EVENT_NH_{ADD,DEL} events to the fib notification chain, which notify capable devices when they should add or delete a nexthop from their tables. Cc: Roopa Prabhu <roopa@cumulusnetworks.com> Cc: David Ahern <dsa@cumulusnetworks.com> Cc: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Reviewed-by: Andy Gospodarek <gospo@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-06net: ipv4: make fib_select_default staticDavid Ahern1-1/+0
fib_select_default has a single caller within the same file. Make it static. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03ipv4: fib: Replay events when registering FIB notifierIdo Schimmel1-1/+2
Commit b90eb7549499 ("fib: introduce FIB notification infrastructure") introduced a new notification chain to notify listeners (f.e., switchdev drivers) about addition and deletion of routes. However, upon registration to the chain the FIB tables can already be populated, which means potential listeners will have an incomplete view of the tables. Solve that by dumping the FIB tables and replaying the events to the passed notification block. The dump itself is done using RCU in order not to starve consumers that need RTNL to make progress. The integrity of the dump is ensured by reading the FIB change sequence counter before and after the dump under RTNL. This allows us to avoid the problematic situation in which the dumping process sends a ENTRY_ADD notification following ENTRY_DEL generated by another process holding RTNL. Callers of the registration function may pass a callback that is executed in case the dump was inconsistent with current FIB tables. The number of retries until a consistent dump is achieved is set to a fixed number to prevent callers from looping for long periods of time. In case current limit proves to be problematic in the future, it can be easily converted to be configurable using a sysctl. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03ipv4: fib: Add fib_info_hold() helperIdo Schimmel1-0/+5
As explained in the previous commit, modules are going to need to take a reference on fib info and then drop it using fib_info_put(). Add the fib_info_hold() helper to make the code more readable and also symmetric with fib_info_put(). Signed-off-by: Ido Schimmel <idosch@mellanox.com> Suggested-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16ipv4: Restore fib_trie_flush_external function and fix call orderingAlexander Duyck1-0/+1
The patch that removed the FIB offload infrastructure was a bit too aggressive and also removed code needed to clean up us splitting the table if additional rules were added. Specifically the function fib_trie_flush_external was called at the end of a new rule being added to flush the foreign trie entries from the main trie. I updated the code so that we only call fib_trie_flush_external on the main table so that we flush the entries for local from main. This way we don't call it for every rule change which is what was happening previously. Fixes: 347e3b28c1ba2 ("switchdev: remove FIB offload infrastructure") Reported-by: Eric Dumazet <edumazet@google.com> Cc: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-28switchdev: remove FIB offload infrastructureJiri Pirko1-2/+0
Since this is now taken care of by FIB notifier, remove the code, with all unused dependencies. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-28fib: introduce FIB info offload flag helpersJiri Pirko1-0/+13
These helpers are to be used in case someone offloads the FIB entry. The result is that if the entry is offloaded to at least one device, the offload flag is set. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-28fib: introduce FIB notification infrastructureJiri Pirko1-3/+31
This allows to pass information about added/deleted FIB entries/rules to whoever is interested. This is done in a very similar way as devinet notifies address additions/removals. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-06net: Don't delete routes in different VRFsMark Tomlinson1-1/+2
When deleting an IP address from an interface, there is a clean-up of routes which refer to this local address. However, there was no check to see that the VRF matched. This meant that deletion wasn't confined to the VRF it should have been. To solve this, a new field has been added to fib_info to hold a table id. When removing fib entries corresponding to a local ip address, this table id is also used in the comparison. The table id is populated when the fib_info is created. This was already done in some places, but not in ip_rt_ioctl(). This has now been fixed. Fixes: 021dd3b8a142 ("net: Add routes to the table associated with the device") Acked-by: David Ahern <dsa@cumulusnetworks.com> Tested-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-18route: check and remove route cache when we get routeXin Long1-0/+1
Since the gc of ipv4 route was removed, the route cached would has no chance to be removed, and even it has been timeout, it still could be used, cause no code to check it's expires. Fix this issue by checking and removing route cache when we get route. Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-08ipv4: eliminate endianness warnings in ip_fib.hLance Richardson1-1/+2
fib_multipath_hash() computes a hash using __be32 values, force cast these to u32 to pacify sparse. Signed-off-by: Lance Richardson <lrichard@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
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 Anastasov1-1/+1
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 Ahern1-0/+2
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 Nørlund1-3/+11
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 Forró1-11/+19
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. Miller1-2/+1
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 Anastasov1-2/+1
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 Prabhu1-1/+4
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 Gospodarek1-7/+9
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 Gospodarek1-2/+2
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 Duyck1-17/+9
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 Feldman1-0/+2
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 Duyck1-28/+42
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 Duyck1-1/+1
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 Duyck1-21/+29
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 Duyck1-2/+2
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 Dumazet1-1/+2
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 Dumazet1-1/+1
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 Perches1-31/+30
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 Rosen1-1/+0
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 Teräs1-1/+2
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 Teräs1-0/+1
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. Lunev1-7/+5
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 Dumazet1-0/+1
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>