netfilter: ipset: support range for IPv4 at adding/deleting elements for hash:*net* types
The range internally is converted to the network(s) equal to the range.
Example:
# ipset new test hash:net
# ipset add test 10.2.0.0-10.2.1.12
# ipset list test
Name: test
Type: hash:net
Header: family inet hashsize 1024 maxelem 65536
Size in memory: 16888
References: 0
Members:
10.2.1.12
10.2.1.0/29
10.2.0.0/24
10.2.1.8/30
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/netfilter/ipset/pfxlen.c b/net/netfilter/ipset/pfxlen.c
index 23f8c81..b57a856 100644
--- a/net/netfilter/ipset/pfxlen.c
+++ b/net/netfilter/ipset/pfxlen.c
@@ -289,3 +289,24 @@
E(0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF),
};
EXPORT_SYMBOL_GPL(ip_set_hostmask_map);
+
+/* Find the largest network which matches the range from left, in host order. */
+u32
+ip_set_range_to_cidr(u32 from, u32 to, u8 *cidr)
+{
+ u32 last;
+ u8 i;
+
+ for (i = 1; i < 32; i++) {
+ if ((from & ip_set_hostmask(i)) != from)
+ continue;
+ last = from | ~ip_set_hostmask(i);
+ if (!after(last, to)) {
+ *cidr = i;
+ return last;
+ }
+ }
+ *cidr = 32;
+ return from;
+}
+EXPORT_SYMBOL_GPL(ip_set_range_to_cidr);