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diff -urN linux.old/include/linux/netfilter_ipv4/ipt_multiport.h linux.dev/include/linux/netfilter_ipv4/ipt_multiport.h
--- linux.old/include/linux/netfilter_ipv4/ipt_multiport.h 2000-12-11 22:31:30.000000000 +0100
+++ linux.dev/include/linux/netfilter_ipv4/ipt_multiport.h 2006-02-04 05:23:54.318518250 +0100
@@ -11,11 +11,12 @@
#define IPT_MULTI_PORTS 15
-/* Must fit inside union ipt_matchinfo: 16 bytes */
-struct ipt_multiport
+struct ipt_multiport_v1
{
u_int8_t flags; /* Type of comparison */
u_int8_t count; /* Number of ports */
u_int16_t ports[IPT_MULTI_PORTS]; /* Ports */
+ u_int8_t pflags[IPT_MULTI_PORTS]; /* Port flags */
+ u_int8_t invert; /* Invert flag */
};
#endif /*_IPT_MULTIPORT_H*/
diff -urN linux.old/net/ipv4/netfilter/ipt_multiport.c linux.dev/net/ipv4/netfilter/ipt_multiport.c
--- linux.old/net/ipv4/netfilter/ipt_multiport.c 2003-06-13 16:51:39.000000000 +0200
+++ linux.dev/net/ipv4/netfilter/ipt_multiport.c 2006-02-04 05:34:27.362081000 +0100
@@ -1,5 +1,14 @@
/* 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>
@@ -8,97 +17,136 @@
#include <linux/netfilter_ipv4/ipt_multiport.h>
#include <linux/netfilter_ipv4/ip_tables.h>
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
+MODULE_DESCRIPTION("iptables multiple port match module");
+
#if 0
#define duprintf(format, args...) printk(format , ## args)
#else
#define duprintf(format, args...)
#endif
+/* from linux 2.6 skbuff.h */
+static inline void *skb_header_pointer(const struct sk_buff *skb, int offset,
+ int len, void *buffer)
+{
+ int hlen = skb_headlen(skb);
+
+ if (hlen - offset >= len)
+ return skb->data + offset;
+
+ if (skb_copy_bits(skb, offset, buffer, len) < 0)
+ return NULL;
+
+ return buffer;
+}
+
+
/* Returns 1 if the port is matched by the test, 0 otherwise. */
static inline int
-ports_match(const u_int16_t *portlist, enum ipt_multiport_flags flags,
- u_int8_t count, u_int16_t src, u_int16_t dst)
+ports_match_v1(const struct ipt_multiport_v1 *minfo,
+ u_int16_t src, u_int16_t dst)
{
unsigned int i;
- for (i=0; i<count; i++) {
- if (flags != IPT_MULTIPORT_DESTINATION
- && portlist[i] == src)
- return 1;
-
- if (flags != IPT_MULTIPORT_SOURCE
- && portlist[i] == dst)
- return 1;
- }
+ u_int16_t s, e;
- return 0;
+ 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 == IPT_MULTIPORT_SOURCE
+ && src >= s && src <= e)
+ return 1 ^ minfo->invert;
+ if (minfo->flags == IPT_MULTIPORT_DESTINATION
+ && dst >= s && dst <= e)
+ return 1 ^ minfo->invert;
+ if (minfo->flags == IPT_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 == IPT_MULTIPORT_SOURCE
+ && src == s)
+ return 1 ^ minfo->invert;
+ if (minfo->flags == IPT_MULTIPORT_DESTINATION
+ && dst == s)
+ return 1 ^ minfo->invert;
+ if (minfo->flags == IPT_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 void *matchinfo,
- int offset,
- const void *hdr,
- u_int16_t datalen,
- int *hotdrop)
+match_v1(const struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ const void *matchinfo,
+ int offset,
+ int *hotdrop)
{
- const struct udphdr *udp = hdr;
- const struct ipt_multiport *multiinfo = matchinfo;
+ u16 _ports[2], *pptr;
+ const struct ipt_multiport_v1 *multiinfo = matchinfo;
+
+ if (offset)
+ return 0;
- /* Must be big enough to read ports. */
- if (offset == 0 && datalen < sizeof(struct udphdr)) {
+ pptr = skb_header_pointer(skb, skb->nh.iph->ihl * 4,
+ 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("ipt_multiport:"
- " Dropping evil offset=0 tinygram.\n");
- *hotdrop = 1;
- return 0;
+ * can't. Hence, no choice but to drop.
+ */
+ duprintf("ipt_multiport:"
+ " Dropping evil offset=0 tinygram.\n");
+ *hotdrop = 1;
+ return 0;
}
- /* Must not be a fragment. */
- return !offset
- && ports_match(multiinfo->ports,
- multiinfo->flags, multiinfo->count,
- ntohs(udp->source), ntohs(udp->dest));
+ return ports_match_v1(multiinfo, ntohs(pptr[0]), ntohs(pptr[1]));
}
-/* Called when user tries to insert an entry of this type. */
static int
-checkentry(const char *tablename,
- const struct ipt_ip *ip,
- void *matchinfo,
- unsigned int matchsize,
- unsigned int hook_mask)
+checkentry_v1(const char *tablename,
+ const struct ipt_ip *ip,
+ void *matchinfo,
+ unsigned int matchsize,
+ unsigned int hook_mask)
{
- const struct ipt_multiport *multiinfo = matchinfo;
-
- if (matchsize != IPT_ALIGN(sizeof(struct ipt_multiport)))
- return 0;
-
- /* Must specify proto == TCP/UDP, no unknown flags or bad count */
- return (ip->proto == IPPROTO_TCP || ip->proto == IPPROTO_UDP)
- && !(ip->invflags & IPT_INV_PROTO)
- && matchsize == IPT_ALIGN(sizeof(struct ipt_multiport))
- && (multiinfo->flags == IPT_MULTIPORT_SOURCE
- || multiinfo->flags == IPT_MULTIPORT_DESTINATION
- || multiinfo->flags == IPT_MULTIPORT_EITHER)
- && multiinfo->count <= IPT_MULTI_PORTS;
+ return (matchsize == IPT_ALIGN(sizeof(struct ipt_multiport_v1)));
}
-static struct ipt_match multiport_match
-= { { NULL, NULL }, "multiport", &match, &checkentry, NULL, THIS_MODULE };
+static struct ipt_match multiport_match_v1 = {
+ .name = "multiport",
+ .match = &match_v1,
+ .checkentry = &checkentry_v1,
+ .me = THIS_MODULE,
+};
static int __init init(void)
{
- return ipt_register_match(&multiport_match);
+ int err;
+
+ err = ipt_register_match(&multiport_match_v1);
+
+ return err;
}
static void __exit fini(void)
{
- ipt_unregister_match(&multiport_match);
+ ipt_unregister_match(&multiport_match_v1);
}
module_init(init);
module_exit(fini);
-MODULE_LICENSE("GPL");
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