From 19a3b7eea42402accf52bcb9ddb51bfdb4d7a13b Mon Sep 17 00:00:00 2001 From: David Ahern Date: Wed, 22 May 2019 12:04:41 -0700 Subject: [PATCH] ipv6: export function to send route updates Add fib6_rt_update to send RTM_NEWROUTE with NLM_F_REPLACE set. This helper will be used by the nexthop code to notify userspace of routes that are impacted when a nexthop config is updated via replace. This notification is needed for legacy apps that do not understand the new nexthop object. Apps that are nexthop aware can use the RTA_NH_ID attribute in the route notification to just ignore it. In the future this should be wrapped in a sysctl to allow OS'es that are fully updated to avoid the notificaton storm. Signed-off-by: David Ahern Signed-off-by: David S. Miller --- include/net/ip6_fib.h | 6 ++++++ include/net/ipv6_stubs.h | 3 +++ net/ipv6/af_inet6.c | 1 + net/ipv6/ip6_fib.c | 8 ++++---- net/ipv6/route.c | 32 ++++++++++++++++++++++++++++++++ 5 files changed, 46 insertions(+), 4 deletions(-) diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h index d038d02cbc3c..0d0d06b1cd26 100644 --- a/include/net/ip6_fib.h +++ b/include/net/ip6_fib.h @@ -452,6 +452,12 @@ int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh, struct netlink_ext_ack *extack); void fib6_nh_release(struct fib6_nh *fib6_nh); +int call_fib6_entry_notifiers(struct net *net, + enum fib_event_type event_type, + struct fib6_info *rt, + struct netlink_ext_ack *extack); +void fib6_rt_update(struct net *net, struct fib6_info *rt, + struct nl_info *info); void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info, unsigned int flags); diff --git a/include/net/ipv6_stubs.h b/include/net/ipv6_stubs.h index 97f42e16b3b3..5c93e942c50b 100644 --- a/include/net/ipv6_stubs.h +++ b/include/net/ipv6_stubs.h @@ -47,6 +47,9 @@ struct ipv6_stub { void (*fib6_nh_release)(struct fib6_nh *fib6_nh); void (*fib6_update_sernum)(struct net *net, struct fib6_info *rt); int (*ip6_del_rt)(struct net *net, struct fib6_info *rt); + void (*fib6_rt_update)(struct net *net, struct fib6_info *rt, + struct nl_info *info); + void (*udpv6_encap_enable)(void); void (*ndisc_send_na)(struct net_device *dev, const struct in6_addr *daddr, const struct in6_addr *solicited_addr, diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index 55138f0d2b9d..cc6f8d0c625a 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -927,6 +927,7 @@ static const struct ipv6_stub ipv6_stub_impl = { .fib6_nh_init = fib6_nh_init, .fib6_nh_release = fib6_nh_release, .fib6_update_sernum = fib6_update_sernum_stub, + .fib6_rt_update = fib6_rt_update, .ip6_del_rt = ip6_del_rt, .udpv6_encap_enable = udpv6_encap_enable, .ndisc_send_na = ndisc_send_na, diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index df726fb8f70f..7958cf91895a 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -393,10 +393,10 @@ static int call_fib6_entry_notifier(struct notifier_block *nb, struct net *net, return call_fib6_notifier(nb, net, event_type, &info.info); } -static int call_fib6_entry_notifiers(struct net *net, - enum fib_event_type event_type, - struct fib6_info *rt, - struct netlink_ext_ack *extack) +int call_fib6_entry_notifiers(struct net *net, + enum fib_event_type event_type, + struct fib6_info *rt, + struct netlink_ext_ack *extack) { struct fib6_entry_notifier_info info = { .info.extack = extack, diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 7a014ca877ed..c52a7f49d096 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -5123,6 +5123,38 @@ void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info, rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err); } +void fib6_rt_update(struct net *net, struct fib6_info *rt, + struct nl_info *info) +{ + u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0; + struct sk_buff *skb; + int err = -ENOBUFS; + + /* call_fib6_entry_notifiers will be removed when in-kernel notifier + * is implemented and supported for nexthop objects + */ + call_fib6_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, rt, NULL); + + skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any()); + if (!skb) + goto errout; + + err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0, + RTM_NEWROUTE, info->portid, seq, NLM_F_REPLACE); + if (err < 0) { + /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */ + WARN_ON(err == -EMSGSIZE); + kfree_skb(skb); + goto errout; + } + rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE, + info->nlh, gfp_any()); + return; +errout: + if (err < 0) + rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err); +} + static int ip6_route_dev_notify(struct notifier_block *this, unsigned long event, void *ptr) { -- 2.45.2