aboutsummaryrefslogtreecommitdiff
path: root/net/ipv4/netfilter/ipt_connbytes.c
diff options
context:
space:
mode:
authorJeff Garzik <jgarzik@pobox.com>2005-09-01 18:02:27 -0400
committerJeff Garzik <jgarzik@pobox.com>2005-09-01 18:02:27 -0400
commitceeec3dc375e3b0618f16b34efc56fe093918f8b (patch)
tree2293d02721ee05131aaf1c60e4fba7e281585eec /net/ipv4/netfilter/ipt_connbytes.c
parentfbff868db3a4cc6a89d51da9a6d49b26c29d04fb (diff)
parente3ee3b78f83688a0ae4315e8be71b2eac559904a (diff)
/spare/repo/netdev-2.6 branch 'ieee80211'
Diffstat (limited to 'net/ipv4/netfilter/ipt_connbytes.c')
-rw-r--r--net/ipv4/netfilter/ipt_connbytes.c162
1 files changed, 162 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/ipt_connbytes.c b/net/ipv4/netfilter/ipt_connbytes.c
new file mode 100644
index 00000000000..df4a42c6da2
--- /dev/null
+++ b/net/ipv4/netfilter/ipt_connbytes.c
@@ -0,0 +1,162 @@
+/* Kernel module to match connection tracking byte counter.
+ * GPL (C) 2002 Martin Devera (devik@cdi.cz).
+ *
+ * 2004-07-20 Harald Welte <laforge@netfilter.org>
+ * - reimplemented to use per-connection accounting counters
+ * - add functionality to match number of packets
+ * - add functionality to match average packet size
+ * - add support to match directions seperately
+ *
+ */
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/netfilter_ipv4/ip_conntrack.h>
+#include <linux/netfilter_ipv4/ip_tables.h>
+#include <linux/netfilter_ipv4/ipt_connbytes.h>
+
+#include <asm/div64.h>
+#include <asm/bitops.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
+MODULE_DESCRIPTION("iptables match for matching number of pkts/bytes per connection");
+
+/* 64bit divisor, dividend and result. dynamic precision */
+static u_int64_t div64_64(u_int64_t dividend, u_int64_t divisor)
+{
+ u_int32_t d = divisor;
+
+ if (divisor > 0xffffffffULL) {
+ unsigned int shift = fls(divisor >> 32);
+
+ d = divisor >> shift;
+ dividend >>= shift;
+ }
+
+ do_div(dividend, d);
+ return dividend;
+}
+
+static int
+match(const struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ const void *matchinfo,
+ int offset,
+ int *hotdrop)
+{
+ const struct ipt_connbytes_info *sinfo = matchinfo;
+ enum ip_conntrack_info ctinfo;
+ struct ip_conntrack *ct;
+ u_int64_t what = 0; /* initialize to make gcc happy */
+
+ if (!(ct = ip_conntrack_get((struct sk_buff *)skb, &ctinfo)))
+ return 0; /* no match */
+
+ switch (sinfo->what) {
+ case IPT_CONNBYTES_PKTS:
+ switch (sinfo->direction) {
+ case IPT_CONNBYTES_DIR_ORIGINAL:
+ what = ct->counters[IP_CT_DIR_ORIGINAL].packets;
+ break;
+ case IPT_CONNBYTES_DIR_REPLY:
+ what = ct->counters[IP_CT_DIR_REPLY].packets;
+ break;
+ case IPT_CONNBYTES_DIR_BOTH:
+ what = ct->counters[IP_CT_DIR_ORIGINAL].packets;
+ what += ct->counters[IP_CT_DIR_REPLY].packets;
+ break;
+ }
+ break;
+ case IPT_CONNBYTES_BYTES:
+ switch (sinfo->direction) {
+ case IPT_CONNBYTES_DIR_ORIGINAL:
+ what = ct->counters[IP_CT_DIR_ORIGINAL].bytes;
+ break;
+ case IPT_CONNBYTES_DIR_REPLY:
+ what = ct->counters[IP_CT_DIR_REPLY].bytes;
+ break;
+ case IPT_CONNBYTES_DIR_BOTH:
+ what = ct->counters[IP_CT_DIR_ORIGINAL].bytes;
+ what += ct->counters[IP_CT_DIR_REPLY].bytes;
+ break;
+ }
+ break;
+ case IPT_CONNBYTES_AVGPKT:
+ switch (sinfo->direction) {
+ case IPT_CONNBYTES_DIR_ORIGINAL:
+ what = div64_64(ct->counters[IP_CT_DIR_ORIGINAL].bytes,
+ ct->counters[IP_CT_DIR_ORIGINAL].packets);
+ break;
+ case IPT_CONNBYTES_DIR_REPLY:
+ what = div64_64(ct->counters[IP_CT_DIR_REPLY].bytes,
+ ct->counters[IP_CT_DIR_REPLY].packets);
+ break;
+ case IPT_CONNBYTES_DIR_BOTH:
+ {
+ u_int64_t bytes;
+ u_int64_t pkts;
+ bytes = ct->counters[IP_CT_DIR_ORIGINAL].bytes +
+ ct->counters[IP_CT_DIR_REPLY].bytes;
+ pkts = ct->counters[IP_CT_DIR_ORIGINAL].packets+
+ ct->counters[IP_CT_DIR_REPLY].packets;
+
+ /* FIXME_THEORETICAL: what to do if sum
+ * overflows ? */
+
+ what = div64_64(bytes, pkts);
+ }
+ break;
+ }
+ break;
+ }
+
+ if (sinfo->count.to)
+ return (what <= sinfo->count.to && what >= sinfo->count.from);
+ else
+ return (what >= sinfo->count.from);
+}
+
+static int check(const char *tablename,
+ const struct ipt_ip *ip,
+ void *matchinfo,
+ unsigned int matchsize,
+ unsigned int hook_mask)
+{
+ const struct ipt_connbytes_info *sinfo = matchinfo;
+
+ if (matchsize != IPT_ALIGN(sizeof(struct ipt_connbytes_info)))
+ return 0;
+
+ if (sinfo->what != IPT_CONNBYTES_PKTS &&
+ sinfo->what != IPT_CONNBYTES_BYTES &&
+ sinfo->what != IPT_CONNBYTES_AVGPKT)
+ return 0;
+
+ if (sinfo->direction != IPT_CONNBYTES_DIR_ORIGINAL &&
+ sinfo->direction != IPT_CONNBYTES_DIR_REPLY &&
+ sinfo->direction != IPT_CONNBYTES_DIR_BOTH)
+ return 0;
+
+ return 1;
+}
+
+static struct ipt_match state_match = {
+ .name = "connbytes",
+ .match = &match,
+ .checkentry = &check,
+ .me = THIS_MODULE
+};
+
+static int __init init(void)
+{
+ return ipt_register_match(&state_match);
+}
+
+static void __exit fini(void)
+{
+ ipt_unregister_match(&state_match);
+}
+
+module_init(init);
+module_exit(fini);