linux/include/net
Stefano Brivio ee28906fd7 ipv4: Dump route exceptions if requested
Since commit 4895c771c7 ("ipv4: Add FIB nexthop exceptions."), cached
exception routes are stored as a separate entity, so they are not dumped
on a FIB dump, even if the RTM_F_CLONED flag is passed.

This implies that the command 'ip route list cache' doesn't return any
result anymore.

If the RTM_F_CLONED is passed, and strict checking requested, retrieve
nexthop exception routes and dump them. If no strict checking is
requested, filtering can't be performed consistently: dump everything in
that case.

With this, we need to add an argument to the netlink callback in order to
track how many entries were already dumped for the last leaf included in
a partial netlink dump.

A single additional argument is sufficient, even if we traverse logically
nested structures (nexthop objects, hash table buckets, bucket chains): it
doesn't matter if we stop in the middle of any of those, because they are
always traversed the same way. As an example, s_i values in [], s_fa
values in ():

  node (fa) #1 [1]
    nexthop #1
    bucket #1 -> #0 in chain (1)
    bucket #2 -> #0 in chain (2) -> #1 in chain (3) -> #2 in chain (4)
    bucket #3 -> #0 in chain (5) -> #1 in chain (6)

    nexthop #2
    bucket #1 -> #0 in chain (7) -> #1 in chain (8)
    bucket #2 -> #0 in chain (9)
  --
  node (fa) #2 [2]
    nexthop #1
    bucket #1 -> #0 in chain (1) -> #1 in chain (2)
    bucket #2 -> #0 in chain (3)

it doesn't matter if we stop at (3), (4), (7) for "node #1", or at (2)
for "node #2": walking flattens all that.

It would even be possible to drop the distinction between the in-tree
(s_i) and in-node (s_fa) counter, but a further improvement might
advise against this. This is only as accurate as the existing tracking
mechanism for leaves: if a partial dump is restarted after exceptions
are removed or expired, we might skip some non-dumped entries.

To improve this, we could attach a 'sernum' attribute (similar to the
one used for IPv6) to nexthop entities, and bump this counter whenever
exceptions change: having a distinction between the two counters would
make this more convenient.

Listing of exception routes (modified routes pre-3.5) was tested against
these versions of kernel and iproute2:

                    iproute2
kernel         4.14.0   4.15.0   4.19.0   5.0.0   5.1.0
 3.5-rc4         +        +        +        +       +
 4.4
 4.9
 4.14
 4.15
 4.19
 5.0
 5.1
 fixed           +        +        +        +       +

v7:
   - Move loop over nexthop objects to route.c, and pass struct fib_info
     and table ID to it, not a struct fib_alias (suggested by David Ahern)
   - While at it, note that the NULL check on fa->fa_info is redundant,
     and the check on RTNH_F_DEAD is also not consistent with what's done
     with regular route listing: just keep it for nhc_flags
   - Rename entry point function for dumping exceptions to
     fib_dump_info_fnhe(), and rearrange arguments for consistency with
     fib_dump_info()
   - Rename fnhe_dump_buckets() to fnhe_dump_bucket() and make it handle
     one bucket at a time
   - Expand commit message to describe why we can have a single "skip"
     counter for all exceptions stored in bucket chains in nexthop objects
     (suggested by David Ahern)

v6:
   - Rebased onto net-next
   - Loop over nexthop paths too. Move loop over fnhe buckets to route.c,
     avoids need to export rt_fill_info() and to touch exceptions from
     fib_trie.c. Pass NULL as flow to rt_fill_info(), it now allows that
     (suggested by David Ahern)

Fixes: 4895c771c7 ("ipv4: Add FIB nexthop exceptions.")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-24 10:18:48 -07:00
..
9p treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 188 2019-05-30 11:29:21 -07:00
bluetooth Bluetooth: Ignore CC events not matching the last HCI command 2019-05-05 19:29:04 +02:00
caif treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194 2019-05-30 11:29:22 -07:00
iucv net/af_iucv: locate IUCV header via skb_network_header() 2018-09-26 09:56:07 -07:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
netns Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-17 20:20:36 -07:00
nfc treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
phonet treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 336 2019-06-05 17:37:07 +02:00
sctp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-05-31 10:49:43 -07:00
tc_act net: sched: act_ctinfo: tidy UAPI definition 2019-06-19 17:11:01 -04:00
6lowpan.h
act_api.h net/sched: let actions use RCU to access 'goto_chain' 2019-03-21 13:26:42 -07:00
addrconf.h vrf: Increment Icmp6InMsgs on the original netdev 2019-06-12 11:00:11 -07:00
af_ieee802154.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
af_rxrpc.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
af_unix.h net: split out functions related to registering inflight socket files 2019-02-28 08:24:23 -07:00
af_vsock.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321 2019-06-05 17:37:05 +02:00
ah.h
arp.h ipv4: Define __ipv4_neigh_lookup_noref when CONFIG_INET is disabled 2019-05-05 11:25:49 -07:00
atmclip.h
ax25.h ax25: fix possible use-after-free 2019-01-23 11:18:00 -08:00
ax88796.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
bond_3ad.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 90 2019-05-24 17:37:53 +02:00
bond_alb.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 5 2019-05-21 11:28:40 +02:00
bond_options.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
bonding.h bonding: add slave_foo printk macros 2019-06-09 13:36:01 -07:00
bpf_sk_storage.h bpf: Introduce bpf sk local storage 2019-04-27 09:07:04 -07:00
busy_poll.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 335 2019-06-05 17:37:06 +02:00
calipso.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13 2019-05-21 11:28:45 +02:00
cfg80211-wext.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cfg80211.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
cfg802154.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
checksum.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
cipso_ipv4.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13 2019-05-21 11:28:45 +02:00
cls_cgroup.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
codel_impl.h
codel_qdisc.h
codel.h
compat.h net: rework SIOCGSTAMP ioctl handling 2019-04-19 14:07:40 -07:00
datalink.h
dcbevent.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201 2019-05-30 11:29:52 -07:00
dcbnl.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201 2019-05-30 11:29:52 -07:00
devlink.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-07 11:00:14 -07:00
dn_dev.h
dn_fib.h
dn_neigh.h
dn_nsp.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 24 2019-05-21 11:52:39 +02:00
dn_route.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 24 2019-05-21 11:52:39 +02:00
dn.h
dsa.h net: dsa: make cpu_dp non const 2019-06-14 20:20:07 -07:00
dsfield.h
dst_cache.h net: core: dst_cache_set_ip6: Rename 'addr' parameter to 'saddr' for consistency 2018-03-05 12:52:45 -05:00
dst_metadata.h
dst_ops.h
dst.h net: dst: remove gc leftovers 2019-03-21 13:39:25 -07:00
erspan.h erspan: set bso bit based on mirrored packet's len 2018-05-20 18:31:42 -04:00
esp.h
ethoc.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
failover.h net: Introduce generic failover module 2018-05-28 22:59:54 -04:00
fib_notifier.h net: fib: drop include of module.h from fib_notifier.h 2019-04-22 21:50:53 -07:00
fib_rules.h net: Set strict_start_type for routes and rules 2019-05-22 17:50:24 -07:00
firewire.h
flow_dissector.h flow_dissector: add support for ingress ifindex dissection 2019-06-19 10:09:21 -04:00
flow_offload.h net: flow_offload: implement support for meta key 2019-06-19 10:09:22 -04:00
flow.h route: Add multipath_hash in flowi_common to make user-define hash 2019-02-27 12:50:17 -08:00
fou.h
fq_impl.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 257 2019-06-05 17:30:27 +02:00
fq.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 257 2019-06-05 17:30:27 +02:00
garp.h
gen_stats.h net: align gnet_stats_basic_cpu struct 2018-11-17 21:37:29 -08:00
genetlink.h genetlink: optionally validate strictly/dumps 2019-04-27 17:07:22 -04:00
geneve.h net: Move the definition of the default Geneve udp port to public header file 2019-03-22 12:09:31 -07:00
gre.h net: Add netif_is_gretap()/netif_is_ip6gretap() 2018-12-10 15:53:04 -08:00
gro_cells.h
gtp.h
gue.h
hwbm.h net: hwbm: Make the hwbm_pool lock a mutex 2019-06-09 19:40:10 -07:00
icmp.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
ieee80211_radiotap.h wireless-drivers-next patches for 5.1 2019-02-22 12:56:24 -08:00
ieee802154_netdev.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
if_inet6.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
ife.h net: ife: drop include of module.h from net/ife.h 2019-04-22 21:50:53 -07:00
ila.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
inet6_connection_sock.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
inet6_hashtables.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
inet_common.h net: use indirect call wrappers at GRO transport layer 2018-12-15 13:23:02 -08:00
inet_connection_sock.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
inet_ecn.h inet: Refactor INET_ECN_decapsulate() 2018-10-17 17:45:07 -07:00
inet_frag.h inet: fix compilation warnings in fqdir_pre_exit() 2019-06-23 11:12:12 -07:00
inet_hashtables.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
inet_sock.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
inet_timewait_sock.h ipv6: tcp: send consistent autoflowlabel in TIME_WAIT state 2019-06-09 20:10:19 -07:00
inetpeer.h net: ipv4: use a dedicated counter for icmp_v4 redirect packets 2019-02-08 21:50:15 -08:00
ip6_checksum.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
ip6_fib.h ipv6: Stop sending in-kernel notifications for each nexthop 2019-06-18 09:45:37 -07:00
ip6_route.h ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREF 2019-06-23 13:24:17 -07:00
ip6_tunnel.h ip6_tunnel: allow not to count pkts on tstats by passing dev as NULL 2019-06-18 20:48:45 -04:00
ip_fib.h fib_frontend, ip6_fib: Select routes or exceptions dump from RTM_F_CLONED 2019-06-24 10:18:48 -07:00
ip_tunnels.h route: Add multipath_hash in flowi_common to make user-define hash 2019-02-27 12:50:17 -08:00
ip_vs.h ipvs: add checksum support for gue encapsulation 2019-05-31 18:23:52 +02:00
ip.h ipv4: tcp: fix ACK/RST sent with a transmit delay 2019-06-14 19:51:12 -07:00
ipcomp.h
ipconfig.h
ipv6_frag.h inet: fix various use-after-free in defrags units 2019-06-19 11:37:47 -04:00
ipv6_stubs.h ipv6: export function to send route updates 2019-05-22 17:48:43 -07:00
ipv6.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-07 11:00:14 -07:00
ipx.h
iw_handler.h net: Spelling s/stucture/structure/ 2018-03-27 09:51:23 +02:00
kcm.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
l3mdev.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
lag.h net: Add lag.h, net_lag_port_dev_txable() 2018-07-11 23:10:19 -07:00
lapb.h
lib80211.h
llc_c_ac.h
llc_c_ev.h
llc_c_st.h
llc_conn.h llc: delete timers synchronously in llc_sk_free() 2018-04-22 14:55:03 -04:00
llc_if.h
llc_pdu.h
llc_s_ac.h
llc_s_ev.h
llc_s_st.h
llc_sap.h
llc.h llc: avoid blocking in llc_sap_close() 2018-09-13 09:04:58 -07:00
lwtunnel.h lwtunnel: Pass encap and encap type attributes to lwtunnel_fill_encap 2019-04-23 19:42:29 -07:00
mac80211.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
mac802154.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
mip6.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13 2019-05-21 11:28:45 +02:00
mld.h
mpls_iptunnel.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295 2019-06-05 17:36:38 +02:00
mpls.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295 2019-06-05 17:36:38 +02:00
mrp.h
ncsi.h
ndisc.h ipv6: Add neighbor helpers that use the ipv6 stub 2019-04-08 15:22:40 -07:00
neighbour.h net ipv6: Prevent neighbor add if protocol is disabled on device 2019-04-17 23:19:07 -07:00
net_failover.h net: Introduce net_failover driver 2018-05-28 22:59:54 -04:00
net_namespace.h netns: add pre_exit method to struct pernet_operations 2019-06-19 11:37:47 -04:00
net_ratelimit.h
netevent.h net: ipv4: Notify about changes to ip_forward_update_priority 2018-08-01 09:52:30 -07:00
netlabel.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13 2019-05-21 11:28:45 +02:00
netlink.h netlink: Add field to skip in-kernel notifications 2019-06-18 09:45:36 -07:00
netprio_cgroup.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
netrom.h net: netrom: Fix error cleanup path of nr_proto_init 2019-04-11 13:59:49 -07:00
nexthop.h nexthops: Add ipv6 helper to walk all fib6_nh in a nexthop struct 2019-06-10 10:44:56 -07:00
nl802154.h
nsh.h
p8022.h
page_pool.h page_pool: fix compile warning when CONFIG_PAGE_POOL is disabled 2019-06-19 21:26:06 -04:00
ping.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
pkt_cls.h net: sched: remove NET_CLS_IND config option 2019-06-15 14:06:13 -07:00
pkt_sched.h net: sched: extend Qdisc with rcu 2018-09-25 20:17:35 -07:00
pptp.h
protocol.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
psample.h net: psample: drop include of module.h from psample.h 2019-04-22 21:50:53 -07:00
psnap.h
raw.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
rawv6.h
red.h
regulatory.h cfg80211: make wmm_rule part of the reg_rule structure 2018-08-28 11:11:47 +02:00
request_sock.h inet: clear num_timeout reqsk_alloc() 2019-06-19 17:46:57 -04:00
rose.h proc: introduce proc_create_seq{,_data} 2018-05-16 07:23:35 +02:00
route.h ipv4: Dump route exceptions if requested 2019-06-24 10:18:48 -07:00
rsi_91x.h Bluetooth: btrsi: add new rsi bluetooth driver 2018-03-13 18:37:02 +02:00
rtnetlink.h net: Add extack argument to rtnl_create_link 2018-11-06 15:00:45 -08:00
rtnh.h net: Rename net/nexthop.h net/rtnh.h 2019-04-22 21:47:25 -07:00
sch_generic.h flow_dissector: switch kernel context to struct bpf_flow_dissector 2019-04-23 18:36:33 +02:00
scm.h pids: Compute task_tgid using signal->leader_pid 2018-07-21 10:43:12 -05:00
secure_seq.h
seg6_hmac.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
seg6_local.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
seg6.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
slhc_vj.h slip: Check if rstate is initialized before uncompressing 2018-04-11 10:33:46 -04:00
smc.h net/smc: add smcd support to the pnet table 2019-02-21 10:34:37 -08:00
snmp.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
sock_reuseport.h bpf: net: Add SO_DETACH_REUSEPORT_BPF 2019-06-15 01:21:19 +02:00
sock.h net: add high_order_alloc_disable sysctl/static key 2019-06-14 20:18:28 -07:00
Space.h net/mac89x0: Convert to platform_driver 2018-03-01 21:21:36 -05:00
stp.h
strparser.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
switchdev.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
tcp_states.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
tcp.h net: fastopen: robustness and endianness fixes for SipHash 2019-06-22 16:30:37 -07:00
timewait_sock.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
tipc.h flow_dissector: do not rely on implicit casts 2018-05-08 00:02:41 -04:00
tls.h net/tls: add kernel-driven resync mechanism for TX 2019-06-11 12:22:27 -07:00
transp_v6.h ipv6: fold sockcm_cookie into ipcm6_cookie 2018-07-07 10:58:49 +09:00
tso.h
tun_proto.h
udp_tunnel.h ipv6: Move ipv6 stubs to a separate header file 2019-03-29 10:53:45 -07:00
udp.h SPDX update for 5.2-rc3, round 1 2019-05-31 08:34:32 -07:00
udplite.h udplite: fix partial checksum initialization 2018-02-16 15:57:42 -05:00
vsock_addr.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321 2019-06-05 17:37:05 +02:00
vxlan.h vxlan: Use FDB_HASH_SIZE hash_locks to reduce contention 2019-06-06 11:08:55 -07:00
wext.h lift handling of SIOCIW... out of dev_ioctl() 2018-01-24 19:13:45 -05:00
wimax.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 268 2019-06-05 17:30:29 +02:00
x25.h
x25device.h
xdp_priv.h xdp: add tracepoints for XDP mem 2019-06-19 11:23:13 -04:00
xdp_sock.h bpf: Allow bpf_map_lookup_elem() on an xskmap 2019-06-10 23:31:26 -07:00
xdp.h xdp: page_pool related fix to cpumap 2019-06-19 11:23:13 -04:00
xfrm.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2019-05-07 22:03:58 -07:00