|
@@ -0,0 +1,314 @@
|
|
|
+/* Kernel module to match one of a list of TCP/UDP ports: ports are in
|
|
|
+ the same place so we can treat them as equal. */
|
|
|
+
|
|
|
+/* (C) 1999-2001 Paul `Rusty' Russell
|
|
|
+ * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
|
|
|
+ *
|
|
|
+ * This program is free software; you can redistribute it and/or modify
|
|
|
+ * it under the terms of the GNU General Public License version 2 as
|
|
|
+ * published by the Free Software Foundation.
|
|
|
+ */
|
|
|
+
|
|
|
+#include <linux/module.h>
|
|
|
+#include <linux/types.h>
|
|
|
+#include <linux/udp.h>
|
|
|
+#include <linux/skbuff.h>
|
|
|
+#include <linux/in.h>
|
|
|
+
|
|
|
+#include <linux/netfilter/xt_multiport.h>
|
|
|
+#include <linux/netfilter/x_tables.h>
|
|
|
+#include <linux/netfilter_ipv4/ip_tables.h>
|
|
|
+#include <linux/netfilter_ipv6/ip6_tables.h>
|
|
|
+
|
|
|
+MODULE_LICENSE("GPL");
|
|
|
+MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
|
|
|
+MODULE_DESCRIPTION("x_tables multiple port match module");
|
|
|
+MODULE_ALIAS("ipt_multiport");
|
|
|
+MODULE_ALIAS("ip6t_multiport");
|
|
|
+
|
|
|
+#if 0
|
|
|
+#define duprintf(format, args...) printk(format , ## args)
|
|
|
+#else
|
|
|
+#define duprintf(format, args...)
|
|
|
+#endif
|
|
|
+
|
|
|
+/* Returns 1 if the port is matched by the test, 0 otherwise. */
|
|
|
+static inline int
|
|
|
+ports_match(const u_int16_t *portlist, enum xt_multiport_flags flags,
|
|
|
+ u_int8_t count, u_int16_t src, u_int16_t dst)
|
|
|
+{
|
|
|
+ unsigned int i;
|
|
|
+ for (i = 0; i < count; i++) {
|
|
|
+ if (flags != XT_MULTIPORT_DESTINATION && portlist[i] == src)
|
|
|
+ return 1;
|
|
|
+
|
|
|
+ if (flags != XT_MULTIPORT_SOURCE && portlist[i] == dst)
|
|
|
+ return 1;
|
|
|
+ }
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+/* Returns 1 if the port is matched by the test, 0 otherwise. */
|
|
|
+static inline int
|
|
|
+ports_match_v1(const struct xt_multiport_v1 *minfo,
|
|
|
+ u_int16_t src, u_int16_t dst)
|
|
|
+{
|
|
|
+ unsigned int i;
|
|
|
+ u_int16_t s, e;
|
|
|
+
|
|
|
+ for (i = 0; i < minfo->count; i++) {
|
|
|
+ s = minfo->ports[i];
|
|
|
+
|
|
|
+ if (minfo->pflags[i]) {
|
|
|
+ /* range port matching */
|
|
|
+ e = minfo->ports[++i];
|
|
|
+ duprintf("src or dst matches with %d-%d?\n", s, e);
|
|
|
+
|
|
|
+ if (minfo->flags == XT_MULTIPORT_SOURCE
|
|
|
+ && src >= s && src <= e)
|
|
|
+ return 1 ^ minfo->invert;
|
|
|
+ if (minfo->flags == XT_MULTIPORT_DESTINATION
|
|
|
+ && dst >= s && dst <= e)
|
|
|
+ return 1 ^ minfo->invert;
|
|
|
+ if (minfo->flags == XT_MULTIPORT_EITHER
|
|
|
+ && ((dst >= s && dst <= e)
|
|
|
+ || (src >= s && src <= e)))
|
|
|
+ return 1 ^ minfo->invert;
|
|
|
+ } else {
|
|
|
+ /* exact port matching */
|
|
|
+ duprintf("src or dst matches with %d?\n", s);
|
|
|
+
|
|
|
+ if (minfo->flags == XT_MULTIPORT_SOURCE
|
|
|
+ && src == s)
|
|
|
+ return 1 ^ minfo->invert;
|
|
|
+ if (minfo->flags == XT_MULTIPORT_DESTINATION
|
|
|
+ && dst == s)
|
|
|
+ return 1 ^ minfo->invert;
|
|
|
+ if (minfo->flags == XT_MULTIPORT_EITHER
|
|
|
+ && (src == s || dst == s))
|
|
|
+ return 1 ^ minfo->invert;
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ return minfo->invert;
|
|
|
+}
|
|
|
+
|
|
|
+static int
|
|
|
+match(const struct sk_buff *skb,
|
|
|
+ const struct net_device *in,
|
|
|
+ const struct net_device *out,
|
|
|
+ const struct xt_match *match,
|
|
|
+ const void *matchinfo,
|
|
|
+ int offset,
|
|
|
+ unsigned int protoff,
|
|
|
+ int *hotdrop)
|
|
|
+{
|
|
|
+ u16 _ports[2], *pptr;
|
|
|
+ const struct xt_multiport *multiinfo = matchinfo;
|
|
|
+
|
|
|
+ if (offset)
|
|
|
+ return 0;
|
|
|
+
|
|
|
+ pptr = skb_header_pointer(skb, protoff, sizeof(_ports), _ports);
|
|
|
+ if (pptr == NULL) {
|
|
|
+ /* We've been asked to examine this packet, and we
|
|
|
+ * can't. Hence, no choice but to drop.
|
|
|
+ */
|
|
|
+ duprintf("xt_multiport: Dropping evil offset=0 tinygram.\n");
|
|
|
+ *hotdrop = 1;
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
+
|
|
|
+ return ports_match(multiinfo->ports,
|
|
|
+ multiinfo->flags, multiinfo->count,
|
|
|
+ ntohs(pptr[0]), ntohs(pptr[1]));
|
|
|
+}
|
|
|
+
|
|
|
+static int
|
|
|
+match_v1(const struct sk_buff *skb,
|
|
|
+ const struct net_device *in,
|
|
|
+ const struct net_device *out,
|
|
|
+ const struct xt_match *match,
|
|
|
+ const void *matchinfo,
|
|
|
+ int offset,
|
|
|
+ unsigned int protoff,
|
|
|
+ int *hotdrop)
|
|
|
+{
|
|
|
+ u16 _ports[2], *pptr;
|
|
|
+ const struct xt_multiport_v1 *multiinfo = matchinfo;
|
|
|
+
|
|
|
+ if (offset)
|
|
|
+ return 0;
|
|
|
+
|
|
|
+ pptr = skb_header_pointer(skb, protoff, sizeof(_ports), _ports);
|
|
|
+ if (pptr == NULL) {
|
|
|
+ /* We've been asked to examine this packet, and we
|
|
|
+ * can't. Hence, no choice but to drop.
|
|
|
+ */
|
|
|
+ duprintf("xt_multiport: Dropping evil offset=0 tinygram.\n");
|
|
|
+ *hotdrop = 1;
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
+
|
|
|
+ return ports_match_v1(multiinfo, ntohs(pptr[0]), ntohs(pptr[1]));
|
|
|
+}
|
|
|
+
|
|
|
+static inline int
|
|
|
+check(u_int16_t proto,
|
|
|
+ u_int8_t ip_invflags,
|
|
|
+ u_int8_t match_flags,
|
|
|
+ u_int8_t count)
|
|
|
+{
|
|
|
+ /* Must specify proto == TCP/UDP, no unknown flags or bad count */
|
|
|
+ return (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
|
|
|
+ && !(ip_invflags & XT_INV_PROTO)
|
|
|
+ && (match_flags == XT_MULTIPORT_SOURCE
|
|
|
+ || match_flags == XT_MULTIPORT_DESTINATION
|
|
|
+ || match_flags == XT_MULTIPORT_EITHER)
|
|
|
+ && count <= XT_MULTI_PORTS;
|
|
|
+}
|
|
|
+
|
|
|
+/* Called when user tries to insert an entry of this type. */
|
|
|
+static int
|
|
|
+checkentry(const char *tablename,
|
|
|
+ const void *info,
|
|
|
+ const struct xt_match *match,
|
|
|
+ void *matchinfo,
|
|
|
+ unsigned int matchsize,
|
|
|
+ unsigned int hook_mask)
|
|
|
+{
|
|
|
+ const struct ipt_ip *ip = info;
|
|
|
+ const struct xt_multiport *multiinfo = matchinfo;
|
|
|
+
|
|
|
+ return check(ip->proto, ip->invflags, multiinfo->flags,
|
|
|
+ multiinfo->count);
|
|
|
+}
|
|
|
+
|
|
|
+static int
|
|
|
+checkentry_v1(const char *tablename,
|
|
|
+ const void *info,
|
|
|
+ const struct xt_match *match,
|
|
|
+ void *matchinfo,
|
|
|
+ unsigned int matchsize,
|
|
|
+ unsigned int hook_mask)
|
|
|
+{
|
|
|
+ const struct ipt_ip *ip = info;
|
|
|
+ const struct xt_multiport_v1 *multiinfo = matchinfo;
|
|
|
+
|
|
|
+ return check(ip->proto, ip->invflags, multiinfo->flags,
|
|
|
+ multiinfo->count);
|
|
|
+}
|
|
|
+
|
|
|
+static int
|
|
|
+checkentry6(const char *tablename,
|
|
|
+ const void *info,
|
|
|
+ const struct xt_match *match,
|
|
|
+ void *matchinfo,
|
|
|
+ unsigned int matchsize,
|
|
|
+ unsigned int hook_mask)
|
|
|
+{
|
|
|
+ const struct ip6t_ip6 *ip = info;
|
|
|
+ const struct xt_multiport *multiinfo = matchinfo;
|
|
|
+
|
|
|
+ return check(ip->proto, ip->invflags, multiinfo->flags,
|
|
|
+ multiinfo->count);
|
|
|
+}
|
|
|
+
|
|
|
+static int
|
|
|
+checkentry6_v1(const char *tablename,
|
|
|
+ const void *info,
|
|
|
+ const struct xt_match *match,
|
|
|
+ void *matchinfo,
|
|
|
+ unsigned int matchsize,
|
|
|
+ unsigned int hook_mask)
|
|
|
+{
|
|
|
+ const struct ip6t_ip6 *ip = info;
|
|
|
+ const struct xt_multiport_v1 *multiinfo = matchinfo;
|
|
|
+
|
|
|
+ return check(ip->proto, ip->invflags, multiinfo->flags,
|
|
|
+ multiinfo->count);
|
|
|
+}
|
|
|
+
|
|
|
+static struct xt_match multiport_match = {
|
|
|
+ .name = "multiport",
|
|
|
+ .revision = 0,
|
|
|
+ .matchsize = sizeof(struct xt_multiport),
|
|
|
+ .match = &match,
|
|
|
+ .checkentry = &checkentry,
|
|
|
+ .family = AF_INET,
|
|
|
+ .me = THIS_MODULE,
|
|
|
+};
|
|
|
+
|
|
|
+static struct xt_match multiport_match_v1 = {
|
|
|
+ .name = "multiport",
|
|
|
+ .revision = 1,
|
|
|
+ .matchsize = sizeof(struct xt_multiport_v1),
|
|
|
+ .match = &match_v1,
|
|
|
+ .checkentry = &checkentry_v1,
|
|
|
+ .family = AF_INET,
|
|
|
+ .me = THIS_MODULE,
|
|
|
+};
|
|
|
+
|
|
|
+static struct xt_match multiport6_match = {
|
|
|
+ .name = "multiport",
|
|
|
+ .revision = 0,
|
|
|
+ .matchsize = sizeof(struct xt_multiport),
|
|
|
+ .match = &match,
|
|
|
+ .checkentry = &checkentry6,
|
|
|
+ .family = AF_INET6,
|
|
|
+ .me = THIS_MODULE,
|
|
|
+};
|
|
|
+
|
|
|
+static struct xt_match multiport6_match_v1 = {
|
|
|
+ .name = "multiport",
|
|
|
+ .revision = 1,
|
|
|
+ .matchsize = sizeof(struct xt_multiport_v1),
|
|
|
+ .match = &match_v1,
|
|
|
+ .checkentry = &checkentry6_v1,
|
|
|
+ .family = AF_INET6,
|
|
|
+ .me = THIS_MODULE,
|
|
|
+};
|
|
|
+
|
|
|
+static int __init xt_multiport_init(void)
|
|
|
+{
|
|
|
+ int ret;
|
|
|
+
|
|
|
+ ret = xt_register_match(&multiport_match);
|
|
|
+ if (ret)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ ret = xt_register_match(&multiport_match_v1);
|
|
|
+ if (ret)
|
|
|
+ goto out_unreg_multi_v0;
|
|
|
+
|
|
|
+ ret = xt_register_match(&multiport6_match);
|
|
|
+ if (ret)
|
|
|
+ goto out_unreg_multi_v1;
|
|
|
+
|
|
|
+ ret = xt_register_match(&multiport6_match_v1);
|
|
|
+ if (ret)
|
|
|
+ goto out_unreg_multi6_v0;
|
|
|
+
|
|
|
+ return ret;
|
|
|
+
|
|
|
+out_unreg_multi6_v0:
|
|
|
+ xt_unregister_match(&multiport6_match);
|
|
|
+out_unreg_multi_v1:
|
|
|
+ xt_unregister_match(&multiport_match_v1);
|
|
|
+out_unreg_multi_v0:
|
|
|
+ xt_unregister_match(&multiport_match);
|
|
|
+out:
|
|
|
+ return ret;
|
|
|
+}
|
|
|
+
|
|
|
+static void __exit xt_multiport_fini(void)
|
|
|
+{
|
|
|
+ xt_unregister_match(&multiport_match);
|
|
|
+ xt_unregister_match(&multiport_match_v1);
|
|
|
+ xt_unregister_match(&multiport6_match);
|
|
|
+ xt_unregister_match(&multiport6_match_v1);
|
|
|
+}
|
|
|
+
|
|
|
+module_init(xt_multiport_init);
|
|
|
+module_exit(xt_multiport_fini);
|