ipmr: add netlink notifications on igmpmsg cache reports
Add Netlink notifications on cache reports in ipmr, in addition to the
existing igmpmsg sent to mroute_sk.
Send RTM_NEWCACHEREPORT notifications to RTNLGRP_IPV4_MROUTE_R.
MSGTYPE, VIF_ID, SRC_ADDR and DST_ADDR Netlink attributes contain the
same data as their equivalent fields in the igmpmsg header.
PKT attribute is the packet sent to mroute_sk, without the added igmpmsg
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>
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 3e7454a..a1d521b 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -109,6 +109,7 @@ static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
struct mfc_cache *c, struct rtmsg *rtm);
static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
int cmd);
+static void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt);
static void mroute_clean_tables(struct mr_table *mrt, bool all);
static void ipmr_expire_process(unsigned long arg);
@@ -995,8 +996,7 @@ static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
}
}
-/* Bounce a cache query up to mrouted. We could use netlink for this but mrouted
- * expects the following bizarre scheme.
+/* Bounce a cache query up to mrouted and netlink.
*
* Called under mrt_lock.
*/
@@ -1062,6 +1062,8 @@ static int ipmr_cache_report(struct mr_table *mrt,
return -EINVAL;
}
+ igmpmsg_netlink_event(mrt, skb);
+
/* Deliver to mrouted */
ret = sock_queue_rcv_skb(mroute_sk, skb);
rcu_read_unlock();
@@ -2341,6 +2343,69 @@ static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err);
}
+static size_t igmpmsg_netlink_msgsize(size_t payloadlen)
+{
+ size_t len =
+ NLMSG_ALIGN(sizeof(struct rtgenmsg))
+ + nla_total_size(1) /* IPMRA_CREPORT_MSGTYPE */
+ + nla_total_size(4) /* IPMRA_CREPORT_VIF_ID */
+ + nla_total_size(4) /* IPMRA_CREPORT_SRC_ADDR */
+ + nla_total_size(4) /* IPMRA_CREPORT_DST_ADDR */
+ /* IPMRA_CREPORT_PKT */
+ + nla_total_size(payloadlen)
+ ;
+
+ return len;
+}
+
+static void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt)
+{
+ struct net *net = read_pnet(&mrt->net);
+ struct nlmsghdr *nlh;
+ struct rtgenmsg *rtgenm;
+ struct igmpmsg *msg;
+ struct sk_buff *skb;
+ struct nlattr *nla;
+ int payloadlen;
+
+ payloadlen = pkt->len - sizeof(struct igmpmsg);
+ msg = (struct igmpmsg *)skb_network_header(pkt);
+
+ skb = nlmsg_new(igmpmsg_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_IPMR;
+ if (nla_put_u8(skb, IPMRA_CREPORT_MSGTYPE, msg->im_msgtype) ||
+ nla_put_u32(skb, IPMRA_CREPORT_VIF_ID, msg->im_vif) ||
+ nla_put_in_addr(skb, IPMRA_CREPORT_SRC_ADDR,
+ msg->im_src.s_addr) ||
+ nla_put_in_addr(skb, IPMRA_CREPORT_DST_ADDR,
+ msg->im_dst.s_addr))
+ goto nla_put_failure;
+
+ nla = nla_reserve(skb, IPMRA_CREPORT_PKT, payloadlen);
+ if (!nla || skb_copy_bits(pkt, sizeof(struct igmpmsg),
+ nla_data(nla), payloadlen))
+ goto nla_put_failure;
+
+ nlmsg_end(skb, nlh);
+
+ rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE_R, NULL, GFP_ATOMIC);
+ return;
+
+nla_put_failure:
+ nlmsg_cancel(skb, nlh);
+errout:
+ kfree_skb(skb);
+ rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE_R, -ENOBUFS);
+}
+
static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
