From 4f75ba6982bc7e37e7738b2f1257d21a9c9e5d31 Mon Sep 17 00:00:00 2001 From: Donald Sharp Date: Wed, 28 Jun 2017 13:58:57 -0400 Subject: [PATCH] net: ipmr: Add ipmr_rtm_getroute Add to RTNL_FAMILY_IPMR, RTM_GETROUTE the ability to retrieve one S,G mroute from a specified table. *,G will return mroute information for just that particular mroute if it exists. This is because it is entirely possible to have more S's then can fit in one skb to return to the requesting process. Signed-off-by: Donald Sharp Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- net/ipv4/ipmr.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 62 insertions(+), 1 deletion(-) diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index a1d521b..bb909f1 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -2406,6 +2406,67 @@ errout: rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE_R, -ENOBUFS); } +static int ipmr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) +{ + struct net *net = sock_net(in_skb->sk); + struct nlattr *tb[RTA_MAX + 1]; + struct sk_buff *skb = NULL; + struct mfc_cache *cache; + struct mr_table *mrt; + struct rtmsg *rtm; + __be32 src, grp; + u32 tableid; + int err; + + err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, + rtm_ipv4_policy, extack); + if (err < 0) + goto errout; + + rtm = nlmsg_data(nlh); + + src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0; + grp = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0; + tableid = tb[RTA_TABLE] ? nla_get_u32(tb[RTA_TABLE]) : 0; + + mrt = ipmr_get_table(net, tableid ? tableid : RT_TABLE_DEFAULT); + if (IS_ERR(mrt)) { + err = PTR_ERR(mrt); + goto errout_free; + } + + /* entries are added/deleted only under RTNL */ + rcu_read_lock(); + cache = ipmr_cache_find(mrt, src, grp); + rcu_read_unlock(); + if (!cache) { + err = -ENOENT; + goto errout_free; + } + + skb = nlmsg_new(mroute_msgsize(false, mrt->maxvif), GFP_KERNEL); + if (!skb) { + err = -ENOBUFS; + goto errout_free; + } + + err = ipmr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid, + nlh->nlmsg_seq, cache, + RTM_NEWROUTE, 0); + if (err < 0) + goto errout_free; + + err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); + +errout: + return err; + +errout_free: + kfree_skb(skb); + goto errout; +} + static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb) { struct net *net = sock_net(skb->sk); @@ -3053,7 +3114,7 @@ int __init ip_mr_init(void) } #endif rtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE, - NULL, ipmr_rtm_dumproute, NULL); + ipmr_rtm_getroute, ipmr_rtm_dumproute, NULL); rtnl_register(RTNL_FAMILY_IPMR, RTM_NEWROUTE, ipmr_rtm_route, NULL, NULL); rtnl_register(RTNL_FAMILY_IPMR, RTM_DELROUTE, -- 2.7.4