ip6mr: add netlink notifications on mrt6msg cache reports

Add Netlink notifications on cache reports in ip6mr, in addition to the
existing mrt6msg sent to mroute6_sk.
Send RTM_NEWCACHEREPORT notifications to RTNLGRP_IPV6_MROUTE_R.

MSGTYPE, MIF_ID, SRC_ADDR and DST_ADDR Netlink attributes contain the
same data as their equivalent fields in the mrt6msg header.
PKT attribute is the packet sent to mroute6_sk, without the added
mrt6msg header.

Suggested-by: Ryan Halbrook <halbrook@arista.com>
Signed-off-by: Julien Gomes <julien@arista.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Julien Gomes 2017-06-20 13:54:18 -07:00 committed by David S. Miller
parent 5a645dd86c
commit dd12d15c9a
2 changed files with 81 additions and 2 deletions

View File

@ -133,4 +133,16 @@ struct mrt6msg {
struct in6_addr im6_src, im6_dst;
};
/* ip6mr netlink cache report attributes */
enum {
IP6MRA_CREPORT_UNSPEC,
IP6MRA_CREPORT_MSGTYPE,
IP6MRA_CREPORT_MIF_ID,
IP6MRA_CREPORT_SRC_ADDR,
IP6MRA_CREPORT_DST_ADDR,
IP6MRA_CREPORT_PKT,
__IP6MRA_CREPORT_MAX
};
#define IP6MRA_CREPORT_MAX (__IP6MRA_CREPORT_MAX - 1)
#endif /* _UAPI__LINUX_MROUTE6_H */

View File

@ -116,6 +116,7 @@ static int __ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
struct mfc6_cache *c, struct rtmsg *rtm);
static void mr6_netlink_event(struct mr6_table *mrt, struct mfc6_cache *mfc,
int cmd);
static void mrt6msg_netlink_event(struct mr6_table *mrt, struct sk_buff *pkt);
static int ip6mr_rtm_dumproute(struct sk_buff *skb,
struct netlink_callback *cb);
static void mroute_clean_tables(struct mr6_table *mrt, bool all);
@ -1125,8 +1126,7 @@ static void ip6mr_cache_resolve(struct net *net, struct mr6_table *mrt,
}
/*
* Bounce a cache query up to pim6sd. We could use netlink for this but pim6sd
* expects the following bizarre scheme.
* Bounce a cache query up to pim6sd and netlink.
*
* Called under mrt_lock.
*/
@ -1208,6 +1208,8 @@ static int ip6mr_cache_report(struct mr6_table *mrt, struct sk_buff *pkt,
return -EINVAL;
}
mrt6msg_netlink_event(mrt, skb);
/*
* Deliver to user space multicast routing algorithms
*/
@ -2457,6 +2459,71 @@ errout:
rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE, err);
}
static size_t mrt6msg_netlink_msgsize(size_t payloadlen)
{
size_t len =
NLMSG_ALIGN(sizeof(struct rtgenmsg))
+ nla_total_size(1) /* IP6MRA_CREPORT_MSGTYPE */
+ nla_total_size(4) /* IP6MRA_CREPORT_MIF_ID */
/* IP6MRA_CREPORT_SRC_ADDR */
+ nla_total_size(sizeof(struct in6_addr))
/* IP6MRA_CREPORT_DST_ADDR */
+ nla_total_size(sizeof(struct in6_addr))
/* IP6MRA_CREPORT_PKT */
+ nla_total_size(payloadlen)
;
return len;
}
static void mrt6msg_netlink_event(struct mr6_table *mrt, struct sk_buff *pkt)
{
struct net *net = read_pnet(&mrt->net);
struct nlmsghdr *nlh;
struct rtgenmsg *rtgenm;
struct mrt6msg *msg;
struct sk_buff *skb;
struct nlattr *nla;
int payloadlen;
payloadlen = pkt->len - sizeof(struct mrt6msg);
msg = (struct mrt6msg *)skb_transport_header(pkt);
skb = nlmsg_new(mrt6msg_netlink_msgsize(payloadlen), GFP_ATOMIC);
if (!skb)
goto errout;
nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
sizeof(struct rtgenmsg), 0);
if (!nlh)
goto errout;
rtgenm = nlmsg_data(nlh);
rtgenm->rtgen_family = RTNL_FAMILY_IP6MR;
if (nla_put_u8(skb, IP6MRA_CREPORT_MSGTYPE, msg->im6_msgtype) ||
nla_put_u32(skb, IP6MRA_CREPORT_MIF_ID, msg->im6_mif) ||
nla_put_in6_addr(skb, IP6MRA_CREPORT_SRC_ADDR,
&msg->im6_src) ||
nla_put_in6_addr(skb, IP6MRA_CREPORT_DST_ADDR,
&msg->im6_dst))
goto nla_put_failure;
nla = nla_reserve(skb, IP6MRA_CREPORT_PKT, payloadlen);
if (!nla || skb_copy_bits(pkt, sizeof(struct mrt6msg),
nla_data(nla), payloadlen))
goto nla_put_failure;
nlmsg_end(skb, nlh);
rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE_R, NULL, GFP_ATOMIC);
return;
nla_put_failure:
nlmsg_cancel(skb, nlh);
errout:
kfree_skb(skb);
rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE_R, -ENOBUFS);
}
static int ip6mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);