--- /dev/null
+/* 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);
git://git.onelab.eu / linux-2.6.git / blobdiff