From 5a645dd86c1be64728578bcb1bdfb96e21815acb Mon Sep 17 00:00:00 2001 From: Julien Gomes Date: Tue, 20 Jun 2017 13:54:17 -0700 Subject: [PATCH] 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 Signed-off-by: Julien Gomes Reviewed-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- include/uapi/linux/mroute.h | 12 +++++++ net/ipv4/ipmr.c | 69 +++++++++++++++++++++++++++++++++++-- 2 files changed, 79 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/mroute.h b/include/uapi/linux/mroute.h index f904367c0cee..e8e5041dea8e 100644 --- a/include/uapi/linux/mroute.h +++ b/include/uapi/linux/mroute.h @@ -152,6 +152,18 @@ enum { }; #define IPMRA_VIFA_MAX (__IPMRA_VIFA_MAX - 1) +/* ipmr netlink cache report attributes */ +enum { + IPMRA_CREPORT_UNSPEC, + IPMRA_CREPORT_MSGTYPE, + IPMRA_CREPORT_VIF_ID, + IPMRA_CREPORT_SRC_ADDR, + IPMRA_CREPORT_DST_ADDR, + IPMRA_CREPORT_PKT, + __IPMRA_CREPORT_MAX +}; +#define IPMRA_CREPORT_MAX (__IPMRA_CREPORT_MAX - 1) + /* That's all usermode folks */ #define MFC_ASSERT_THRESH (3*HZ) /* Maximal freq. of asserts */ diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 3e7454aa49e8..a1d521be612b 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 @@ errout: 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); -- 2.20.1