[NETFILTER]: ip6_tables: consolidate dst and hbh matches

The matches are identical besides one looking for NEXTHDR_HOP, the other
for NEXTHDR_DEST. Remove ip6t_dst.c and handle both in ip6t_hbh.c.
Signed-off-by: Patrick McHardy <kaber@trash,net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/netfilter/Makefile

@@ -5,7 +5,7 @@
 # Link order matters here.
 obj-$(CONFIG_IP6_NF_IPTABLES) += ip6_tables.o
 obj-$(CONFIG_IP6_NF_MATCH_RT) += ip6t_rt.o
-obj-$(CONFIG_IP6_NF_MATCH_OPTS) += ip6t_hbh.o ip6t_dst.o
+obj-$(CONFIG_IP6_NF_MATCH_OPTS) += ip6t_hbh.o
 obj-$(CONFIG_IP6_NF_MATCH_IPV6HEADER) += ip6t_ipv6header.o
 obj-$(CONFIG_IP6_NF_MATCH_FRAG) += ip6t_frag.o
 obj-$(CONFIG_IP6_NF_MATCH_AH) += ip6t_ah.o

net/ipv6/netfilter/ip6t_dst.c

-/* Kernel module to match Hop-by-Hop and Destination parameters. */
-
-/* (C) 2001-2002 Andras Kis-Szabo <kisza@sch.bme.hu>
- *
- * 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/skbuff.h>
-#include <linux/ipv6.h>
-#include <linux/types.h>
-#include <net/checksum.h>
-#include <net/ipv6.h>
-
-#include <asm/byteorder.h>
-
-#include <linux/netfilter_ipv6/ip6_tables.h>
-#include <linux/netfilter_ipv6/ip6t_opts.h>
-
-#define HOPBYHOP	0
-
-MODULE_LICENSE("GPL");
-#if HOPBYHOP
-MODULE_DESCRIPTION("IPv6 HbH match");
-#else
-MODULE_DESCRIPTION("IPv6 DST match");
-#endif
-MODULE_AUTHOR("Andras Kis-Szabo <kisza@sch.bme.hu>");
-
-#if 0
-#define DEBUGP printk
-#else
-#define DEBUGP(format, args...)
-#endif
-
-/*
- *  (Type & 0xC0) >> 6
- *	0	-> ignorable
- *	1	-> must drop the packet
- *	2	-> send ICMP PARM PROB regardless and drop packet
- *	3	-> Send ICMP if not a multicast address and drop packet
- *  (Type & 0x20) >> 5
- *	0	-> invariant
- *	1	-> can change the routing
- *  (Type & 0x1F) Type
- *	0	-> Pad1 (only 1 byte!)
- *	1	-> PadN LENGTH info (total length = length + 2)
- *	C0 | 2	-> JUMBO 4 x x x x ( xxxx > 64k )
- *	5	-> RTALERT 2 x x
- */
-
-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)
-{
-	struct ipv6_opt_hdr _optsh, *oh;
-	const struct ip6t_opts *optinfo = matchinfo;
-	unsigned int temp;
-	unsigned int ptr;
-	unsigned int hdrlen = 0;
-	unsigned int ret = 0;
-	u8 _opttype, *tp = NULL;
-	u8 _optlen, *lp = NULL;
-	unsigned int optlen;
-
-#if HOPBYHOP
-	if (ipv6_find_hdr(skb, &ptr, NEXTHDR_HOP, NULL) < 0)
-#else
-	if (ipv6_find_hdr(skb, &ptr, NEXTHDR_DEST, NULL) < 0)
-#endif
-		return 0;
-
-	oh = skb_header_pointer(skb, ptr, sizeof(_optsh), &_optsh);
-	if (oh == NULL) {
-		*hotdrop = 1;
-		return 0;
-	}
-
-	hdrlen = ipv6_optlen(oh);
-	if (skb->len - ptr < hdrlen) {
-		/* Packet smaller than it's length field */
-		return 0;
-	}
-
-	DEBUGP("IPv6 OPTS LEN %u %u ", hdrlen, oh->hdrlen);
-
-	DEBUGP("len %02X %04X %02X ",
-	       optinfo->hdrlen, hdrlen,
-	       (!(optinfo->flags & IP6T_OPTS_LEN) ||
-		((optinfo->hdrlen == hdrlen) ^
-		 !!(optinfo->invflags & IP6T_OPTS_INV_LEN))));
-
-	ret = (oh != NULL) &&
-	      (!(optinfo->flags & IP6T_OPTS_LEN) ||
-	       ((optinfo->hdrlen == hdrlen) ^
-		!!(optinfo->invflags & IP6T_OPTS_INV_LEN)));
-
-	ptr += 2;
-	hdrlen -= 2;
-	if (!(optinfo->flags & IP6T_OPTS_OPTS)) {
-		return ret;
-	} else if (optinfo->flags & IP6T_OPTS_NSTRICT) {
-		DEBUGP("Not strict - not implemented");
-	} else {
-		DEBUGP("Strict ");
-		DEBUGP("#%d ", optinfo->optsnr);
-		for (temp = 0; temp < optinfo->optsnr; temp++) {
-			/* type field exists ? */
-			if (hdrlen < 1)
-				break;
-			tp = skb_header_pointer(skb, ptr, sizeof(_opttype),
-						&_opttype);
-			if (tp == NULL)
-				break;
-
-			/* Type check */
-			if (*tp != (optinfo->opts[temp] & 0xFF00) >> 8) {
-				DEBUGP("Tbad %02X %02X\n",
-				       *tp,
-				       (optinfo->opts[temp] & 0xFF00) >> 8);
-				return 0;
-			} else {
-				DEBUGP("Tok ");
-			}
-			/* Length check */
-			if (*tp) {
-				u16 spec_len;
-
-				/* length field exists ? */
-				if (hdrlen < 2)
-					break;
-				lp = skb_header_pointer(skb, ptr + 1,
-							sizeof(_optlen),
-							&_optlen);
-				if (lp == NULL)
-					break;
-				spec_len = optinfo->opts[temp] & 0x00FF;
-
-				if (spec_len != 0x00FF && spec_len != *lp) {
-					DEBUGP("Lbad %02X %04X\n", *lp,
-					       spec_len);
-					return 0;
-				}
-				DEBUGP("Lok ");
-				optlen = *lp + 2;
-			} else {
-				DEBUGP("Pad1\n");
-				optlen = 1;
-			}
-
-			/* Step to the next */
-			DEBUGP("len%04X \n", optlen);
-
-			if ((ptr > skb->len - optlen || hdrlen < optlen) &&
-			    (temp < optinfo->optsnr - 1)) {
-				DEBUGP("new pointer is too large! \n");
-				break;
-			}
-			ptr += optlen;
-			hdrlen -= optlen;
-		}
-		if (temp == optinfo->optsnr)
-			return ret;
-		else
-			return 0;
-	}
-
-	return 0;
-}
-
-/* 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 hook_mask)
-{
-	const struct ip6t_opts *optsinfo = matchinfo;
-
-	if (optsinfo->invflags & ~IP6T_OPTS_INV_MASK) {
-		DEBUGP("ip6t_opts: unknown flags %X\n", optsinfo->invflags);
-		return 0;
-	}
-	return 1;
-}
-
-static struct ip6t_match opts_match = {
-#if HOPBYHOP
-	.name		= "hbh",
-#else
-	.name		= "dst",
-#endif
-	.match		= match,
-	.matchsize	= sizeof(struct ip6t_opts),
-	.checkentry	= checkentry,
-	.me		= THIS_MODULE,
-};
-
-static int __init ip6t_dst_init(void)
-{
-	return ip6t_register_match(&opts_match);
-}
-
-static void __exit ip6t_dst_fini(void)
-{
-	ip6t_unregister_match(&opts_match);
-}
-
-module_init(ip6t_dst_init);
-module_exit(ip6t_dst_fini);

net/ipv6/netfilter/ip6t_hbh.c

@@ -19,15 +19,10 @@
 #include <linux/netfilter_ipv6/ip6_tables.h>
 #include <linux/netfilter_ipv6/ip6t_opts.h>
 
-#define HOPBYHOP	1
-
 MODULE_LICENSE("GPL");
-#if HOPBYHOP
-MODULE_DESCRIPTION("IPv6 HbH match");
-#else
-MODULE_DESCRIPTION("IPv6 DST match");
-#endif
+MODULE_DESCRIPTION("IPv6 opts match");
 MODULE_AUTHOR("Andras Kis-Szabo <kisza@sch.bme.hu>");
+MODULE_ALIAS("ip6t_dst");
 
 #if 0
 #define DEBUGP printk
@@ -71,11 +66,7 @@ match(const struct sk_buff *skb,
 	u8 _optlen, *lp = NULL;
 	unsigned int optlen;
 
-#if HOPBYHOP
-	if (ipv6_find_hdr(skb, &ptr, NEXTHDR_HOP, NULL) < 0)
-#else
-	if (ipv6_find_hdr(skb, &ptr, NEXTHDR_DEST, NULL) < 0)
-#endif
+	if (ipv6_find_hdr(skb, &ptr, match->data, NULL) < 0)
 		return 0;
 
 	oh = skb_header_pointer(skb, ptr, sizeof(_optsh), &_optsh);
@@ -193,26 +184,35 @@ checkentry(const char *tablename,
 	return 1;
 }
 
-static struct ip6t_match opts_match = {
-#if HOPBYHOP
-	.name		= "hbh",
-#else
-	.name		= "dst",
-#endif
-	.match		= match,
-	.matchsize	= sizeof(struct ip6t_opts),
-	.checkentry	= checkentry,
-	.me		= THIS_MODULE,
+static struct xt_match opts_match[] = {
+	{
+		.name		= "hbh",
+		.family		= AF_INET6,
+		.match		= match,
+		.matchsize	= sizeof(struct ip6t_opts),
+		.checkentry	= checkentry,
+		.me		= THIS_MODULE,
+		.data		= NEXTHDR_HOP,
+	},
+	{
+		.name		= "dst",
+		.family		= AF_INET6,
+		.match		= match,
+		.matchsize	= sizeof(struct ip6t_opts),
+		.checkentry	= checkentry,
+		.me		= THIS_MODULE,
+		.data		= NEXTHDR_DEST,
+	},
 };
 
 static int __init ip6t_hbh_init(void)
 {
-	return ip6t_register_match(&opts_match);
+	return xt_register_matches(opts_match, ARRAY_SIZE(opts_match));
 }
 
 static void __exit ip6t_hbh_fini(void)
 {
-	ip6t_unregister_match(&opts_match);
+	xt_unregister_matches(opts_match, ARRAY_SIZE(opts_match));
 }
 
 module_init(ip6t_hbh_init);