[NET]: Introduce RTA_TABLE/FRA_TABLE attributes

Introduce RTA_TABLE route attribute and FRA_TABLE routing rule attribute
to hold 32 bit routing table IDs. Usespace compatibility is provided by
continuing to accept and send the rtm_table field, but because of its
limited size it can only carry the low 8 bits of the table ID. This
implies that if larger IDs are used, _all_ userspace programs using them
need to use RTA_TABLE.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 7 insertions, 3 deletions

diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 06f4b23f6f57..2696ede52de2 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -294,7 +294,8 @@ static int inet_check_attr(struct rtmsg *r, struct rtattr **rta)
                 if (attr) {
                         if (RTA_PAYLOAD(attr) < 4)
                                 return -EINVAL;
-                        if (i != RTA_MULTIPATH && i != RTA_METRICS)
+                        if (i != RTA_MULTIPATH && i != RTA_METRICS &&
+                            i != RTA_TABLE)
                                 *rta = (struct rtattr*)RTA_DATA(attr);
                 }
         }
@@ -310,7 +311,7 @@ int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
         if (inet_check_attr(r, rta))
                 return -EINVAL;
 
-        tb = fib_get_table(r->rtm_table);
+        tb = fib_get_table(rtm_get_table(rta, r->rtm_table));
         if (tb)
                 return tb->tb_delete(tb, r, (struct kern_rta*)rta, nlh, &NETLINK_CB(skb));
         return -ESRCH;
@@ -325,7 +326,7 @@ int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
         if (inet_check_attr(r, rta))
                 return -EINVAL;
 
-        tb = fib_new_table(r->rtm_table);
+        tb = fib_new_table(rtm_get_table(rta, r->rtm_table));
         if (tb)
                 return tb->tb_insert(tb, r, (struct kern_rta*)rta, nlh, &NETLINK_CB(skb));
         return -ENOBUFS;
diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c
index 58fb91b00fdf..0330b9cc4b58 100644
--- a/net/ipv4/fib_rules.c
+++ b/net/ipv4/fib_rules.c
@@ -184,6 +184,7 @@ static struct nla_policy fib4_rule_policy[FRA_MAX+1] __read_mostly = {
         [FRA_DST]       = { .type = NLA_U32 },
         [FRA_FWMARK]    = { .type = NLA_U32 },
         [FRA_FLOW]      = { .type = NLA_U32 },
+        [FRA_TABLE]     = { .type = NLA_U32 },
 };
 
 static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index c7a112b5a185..ab753df20a39 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -953,6 +953,7 @@ fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
         rtm->rtm_src_len = 0;
         rtm->rtm_tos = tos;
         rtm->rtm_table = tb_id;
+        RTA_PUT_U32(skb, RTA_TABLE, tb_id);
         rtm->rtm_type = type;
         rtm->rtm_flags = fi->fib_flags;
         rtm->rtm_scope = scope;
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index b873cbcdd0b8..12128b82c9dc 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2652,6 +2652,7 @@ static int rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
         r->rtm_src_len  = 0;
         r->rtm_tos      = rt->fl.fl4_tos;
         r->rtm_table    = RT_TABLE_MAIN;
+        RTA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
         r->rtm_type     = rt->rt_type;
         r->rtm_scope    = RT_SCOPE_UNIVERSE;
         r->rtm_protocol = RTPROT_UNSPEC;