ipv6: ip6mr: add support for dumping routing tables over netlink
The ip6mr /proc interface (ip6_mr_cache) can't be extended to dump routes
from any tables but the main table in a backwards compatible fashion since
the output format ends in a variable amount of output interfaces.
Introduce a new netlink interface to dump multicast routes from all tables,
similar to the netlink interface for regular routes.
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index c2920a1..163850e 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -112,8 +112,10 @@
struct sk_buff *skb, struct mfc6_cache *cache);
static int ip6mr_cache_report(struct mr6_table *mrt, struct sk_buff *pkt,
mifi_t mifi, int assert);
-static int ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
- struct mfc6_cache *c, struct rtmsg *rtm);
+static int __ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
+ struct mfc6_cache *c, struct rtmsg *rtm);
+static int ip6mr_rtm_dumproute(struct sk_buff *skb,
+ struct netlink_callback *cb);
static void mroute_clean_tables(struct mr6_table *mrt);
static void ipmr_expire_process(unsigned long arg);
@@ -1038,7 +1040,7 @@
int err;
struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct ipv6hdr));
- if (ip6mr_fill_mroute(mrt, skb, c, NLMSG_DATA(nlh)) > 0) {
+ if (__ip6mr_fill_mroute(mrt, skb, c, NLMSG_DATA(nlh)) > 0) {
nlh->nlmsg_len = skb_tail_pointer(skb) - (u8 *)nlh;
} else {
nlh->nlmsg_type = NLMSG_ERROR;
@@ -1350,6 +1352,7 @@
goto add_proto_fail;
}
#endif
+ rtnl_register(RTNL_FAMILY_IP6MR, RTM_GETROUTE, NULL, ip6mr_rtm_dumproute);
return 0;
#ifdef CONFIG_IPV6_PIMSM_V2
add_proto_fail:
@@ -2007,9 +2010,8 @@
}
-static int
-ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
- struct mfc6_cache *c, struct rtmsg *rtm)
+static int __ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
+ struct mfc6_cache *c, struct rtmsg *rtm)
{
int ct;
struct rtnexthop *nhp;
@@ -2111,8 +2113,88 @@
if (!nowait && (rtm->rtm_flags&RTM_F_NOTIFY))
cache->mfc_flags |= MFC_NOTIFY;
- err = ip6mr_fill_mroute(mrt, skb, cache, rtm);
+ err = __ip6mr_fill_mroute(mrt, skb, cache, rtm);
read_unlock(&mrt_lock);
return err;
}
+static int ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
+ u32 pid, u32 seq, struct mfc6_cache *c)
+{
+ struct nlmsghdr *nlh;
+ struct rtmsg *rtm;
+
+ nlh = nlmsg_put(skb, pid, seq, RTM_NEWROUTE, sizeof(*rtm), NLM_F_MULTI);
+ if (nlh == NULL)
+ return -EMSGSIZE;
+
+ rtm = nlmsg_data(nlh);
+ rtm->rtm_family = RTNL_FAMILY_IPMR;
+ rtm->rtm_dst_len = 128;
+ rtm->rtm_src_len = 128;
+ rtm->rtm_tos = 0;
+ rtm->rtm_table = mrt->id;
+ NLA_PUT_U32(skb, RTA_TABLE, mrt->id);
+ rtm->rtm_scope = RT_SCOPE_UNIVERSE;
+ rtm->rtm_protocol = RTPROT_UNSPEC;
+ rtm->rtm_flags = 0;
+
+ NLA_PUT(skb, RTA_SRC, 16, &c->mf6c_origin);
+ NLA_PUT(skb, RTA_DST, 16, &c->mf6c_mcastgrp);
+
+ if (__ip6mr_fill_mroute(mrt, skb, c, rtm) < 0)
+ goto nla_put_failure;
+
+ return nlmsg_end(skb, nlh);
+
+nla_put_failure:
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
+}
+
+static int ip6mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct net *net = sock_net(skb->sk);
+ struct mr6_table *mrt;
+ struct mfc6_cache *mfc;
+ unsigned int t = 0, s_t;
+ unsigned int h = 0, s_h;
+ unsigned int e = 0, s_e;
+
+ s_t = cb->args[0];
+ s_h = cb->args[1];
+ s_e = cb->args[2];
+
+ read_lock(&mrt_lock);
+ ip6mr_for_each_table(mrt, net) {
+ if (t < s_t)
+ goto next_table;
+ if (t > s_t)
+ s_h = 0;
+ for (h = s_h; h < MFC6_LINES; h++) {
+ list_for_each_entry(mfc, &mrt->mfc6_cache_array[h], list) {
+ if (e < s_e)
+ goto next_entry;
+ if (ip6mr_fill_mroute(mrt, skb,
+ NETLINK_CB(cb->skb).pid,
+ cb->nlh->nlmsg_seq,
+ mfc) < 0)
+ goto done;
+next_entry:
+ e++;
+ }
+ e = s_e = 0;
+ }
+ s_h = 0;
+next_table:
+ t++;
+ }
+done:
+ read_unlock(&mrt_lock);
+
+ cb->args[2] = e;
+ cb->args[1] = h;
+ cb->args[0] = t;
+
+ return skb->len;
+}
