From 8c14586fc320acfed8a0048eb21d1f2e2856fc36 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Sun, 24 Apr 2016 21:26:04 -0700 Subject: [PATCH] net: ipv6: Use passed in table for nexthop lookups Similar to 3bfd847203c6 ("net: Use passed in table for nexthop lookups") for IPv4, if the route spec contains a table id use that to lookup the next hop first and fall back to a full lookup if it fails (per the fix 4c9bcd117918b ("net: Fix nexthop lookups")). Example: root@kenny:~# ip -6 ro ls table red local 2100:1::1 dev lo proto none metric 0 pref medium 2100:1::/120 dev eth1 proto kernel metric 256 pref medium local 2100:2::1 dev lo proto none metric 0 pref medium 2100:2::/120 dev eth2 proto kernel metric 256 pref medium local fe80::e0:f9ff:fe09:3cac dev lo proto none metric 0 pref medium local fe80::e0:f9ff:fe1c:b974 dev lo proto none metric 0 pref medium fe80::/64 dev eth1 proto kernel metric 256 pref medium fe80::/64 dev eth2 proto kernel metric 256 pref medium ff00::/8 dev red metric 256 pref medium ff00::/8 dev eth1 metric 256 pref medium ff00::/8 dev eth2 metric 256 pref medium unreachable default dev lo metric 240 error -113 pref medium root@kenny:~# ip -6 ro add table red 2100:3::/64 via 2100:1::64 RTNETLINK answers: No route to host Route add fails even though 2100:1::64 is a reachable next hop: root@kenny:~# ping6 -I red 2100:1::64 ping6: Warning: source address might be selected on device other than red. PING 2100:1::64(2100:1::64) from 2100:1::1 red: 56 data bytes 64 bytes from 2100:1::64: icmp_seq=1 ttl=64 time=1.33 ms With this patch: root@kenny:~# ip -6 ro add table red 2100:3::/64 via 2100:1::64 root@kenny:~# ip -6 ro ls table red local 2100:1::1 dev lo proto none metric 0 pref medium 2100:1::/120 dev eth1 proto kernel metric 256 pref medium local 2100:2::1 dev lo proto none metric 0 pref medium 2100:2::/120 dev eth2 proto kernel metric 256 pref medium 2100:3::/64 via 2100:1::64 dev eth1 metric 1024 pref medium local fe80::e0:f9ff:fe09:3cac dev lo proto none metric 0 pref medium local fe80::e0:f9ff:fe1c:b974 dev lo proto none metric 0 pref medium fe80::/64 dev eth1 proto kernel metric 256 pref medium fe80::/64 dev eth2 proto kernel metric 256 pref medium ff00::/8 dev red metric 256 pref medium ff00::/8 dev eth1 metric 256 pref medium ff00::/8 dev eth2 metric 256 pref medium unreachable default dev lo metric 240 error -113 pref medium Signed-off-by: David Ahern Signed-off-by: David S. Miller --- net/ipv6/route.c | 40 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 38 insertions(+), 2 deletions(-) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index d916d6ab9ad2..af46e19205f5 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1769,6 +1769,37 @@ static int ip6_convert_metrics(struct mx6_config *mxc, return -EINVAL; } +static struct rt6_info *ip6_nh_lookup_table(struct net *net, + struct fib6_config *cfg, + const struct in6_addr *gw_addr) +{ + struct flowi6 fl6 = { + .flowi6_oif = cfg->fc_ifindex, + .daddr = *gw_addr, + .saddr = cfg->fc_prefsrc, + }; + struct fib6_table *table; + struct rt6_info *rt; + int flags = 0; + + table = fib6_get_table(net, cfg->fc_table); + if (!table) + return NULL; + + if (!ipv6_addr_any(&cfg->fc_prefsrc)) + flags |= RT6_LOOKUP_F_HAS_SADDR; + + rt = ip6_pol_route(net, table, cfg->fc_ifindex, &fl6, flags); + + /* if table lookup failed, fall back to full lookup */ + if (rt == net->ipv6.ip6_null_entry) { + ip6_rt_put(rt); + rt = NULL; + } + + return rt; +} + static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg) { struct net *net = cfg->fc_nlinfo.nl_net; @@ -1940,7 +1971,7 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg) rt->rt6i_gateway = *gw_addr; if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) { - struct rt6_info *grt; + struct rt6_info *grt = NULL; /* IPv6 strictly inhibits using not link-local addresses as nexthop address. @@ -1952,7 +1983,12 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg) if (!(gwa_type & IPV6_ADDR_UNICAST)) goto out; - grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1); + if (cfg->fc_table) + grt = ip6_nh_lookup_table(net, cfg, gw_addr); + + if (!grt) + grt = rt6_lookup(net, gw_addr, NULL, + cfg->fc_ifindex, 1); err = -EHOSTUNREACH; if (!grt) -- 2.39.2