extensions: add IPv6 capable ECN match extension

Patrick submitted this patch by 9th Jun 2011, I'm recovering
and applying it to iptables.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

4 files changed, 66 insertions, 67 deletions

diff --git a/extensions/libipt_ecn.c b/extensions/libxt_ecn.c
index 56a0347e..286782a3 100644
--- a/extensions/libipt_ecn.c
+++ b/extensions/libxt_ecn.c
@@ -1,6 +1,7 @@
 /* Shared library add-on to iptables for ECN matching
  *
- * (C) 2002 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2002 by Harald Welte <laforge@netfilter.org>
+ * (C) 2011 by Patrick McHardy <kaber@trash.net>
  *
  * This program is distributed under the terms of GNU GPL v2, 1991
  *
@@ -9,7 +10,7 @@
  */
 #include <stdio.h>
 #include <xtables.h>
-#include <linux/netfilter_ipv4/ipt_ecn.h>
+#include <linux/netfilter/xt_ecn.h>
 
 enum {
 	O_ECN_TCP_CWR = 0,
@@ -23,7 +24,7 @@ static void ecn_help(void)
 "ECN match options\n"
 "[!] --ecn-tcp-cwr 		Match CWR bit of TCP header\n"
 "[!] --ecn-tcp-ece		Match ECE bit of TCP header\n"
-"[!] --ecn-ip-ect [0..3]	Match ECN codepoint in IPv4 header\n");
+"[!] --ecn-ip-ect [0..3]	Match ECN codepoint in IPv4/IPv6 header\n");
 }
 
 static const struct xt_option_entry ecn_opts[] = {
@@ -38,24 +39,24 @@ static const struct xt_option_entry ecn_opts[] = {
 
 static void ecn_parse(struct xt_option_call *cb)
 {
-	struct ipt_ecn_info *einfo = cb->data;
+	struct xt_ecn_info *einfo = cb->data;
 
 	xtables_option_parse(cb);
 	switch (cb->entry->id) {
 	case O_ECN_TCP_CWR:
-		einfo->operation |= IPT_ECN_OP_MATCH_CWR;
+		einfo->operation |= XT_ECN_OP_MATCH_CWR;
 		if (cb->invert)
-			einfo->invert |= IPT_ECN_OP_MATCH_CWR;
+			einfo->invert |= XT_ECN_OP_MATCH_CWR;
 		break;
 	case O_ECN_TCP_ECE:
-		einfo->operation |= IPT_ECN_OP_MATCH_ECE;
+		einfo->operation |= XT_ECN_OP_MATCH_ECE;
 		if (cb->invert)
-			einfo->invert |= IPT_ECN_OP_MATCH_ECE;
+			einfo->invert |= XT_ECN_OP_MATCH_ECE;
 		break;
 	case O_ECN_IP_ECT:
 		if (cb->invert)
-			einfo->invert |= IPT_ECN_OP_MATCH_IP;
-		einfo->operation |= IPT_ECN_OP_MATCH_IP;
+			einfo->invert |= XT_ECN_OP_MATCH_IP;
+		einfo->operation |= XT_ECN_OP_MATCH_IP;
 		einfo->ip_ect = cb->val.u8;
 		break;
 	}
@@ -71,47 +72,47 @@ static void ecn_check(struct xt_fcheck_call *cb)
 static void ecn_print(const void *ip, const struct xt_entry_match *match,
                       int numeric)
 {
-	const struct ipt_ecn_info *einfo =
-		(const struct ipt_ecn_info *)match->data;
+	const struct xt_ecn_info *einfo =
+		(const struct xt_ecn_info *)match->data;
 
 	printf(" ECN match");
 
-	if (einfo->operation & IPT_ECN_OP_MATCH_ECE) {
+	if (einfo->operation & XT_ECN_OP_MATCH_ECE) {
 		printf(" %sECE",
-		       (einfo->invert & IPT_ECN_OP_MATCH_ECE) ? "!" : "");
+		       (einfo->invert & XT_ECN_OP_MATCH_ECE) ? "!" : "");
 	}
 
-	if (einfo->operation & IPT_ECN_OP_MATCH_CWR) {
+	if (einfo->operation & XT_ECN_OP_MATCH_CWR) {
 		printf(" %sCWR",
-		       (einfo->invert & IPT_ECN_OP_MATCH_CWR) ? "!" : "");
+		       (einfo->invert & XT_ECN_OP_MATCH_CWR) ? "!" : "");
 	}
 
-	if (einfo->operation & IPT_ECN_OP_MATCH_IP) {
+	if (einfo->operation & XT_ECN_OP_MATCH_IP) {
 		printf(" %sECT=%d",
-		       (einfo->invert & IPT_ECN_OP_MATCH_IP) ? "!" : "",
+		       (einfo->invert & XT_ECN_OP_MATCH_IP) ? "!" : "",
 		       einfo->ip_ect);
 	}
 }
 
 static void ecn_save(const void *ip, const struct xt_entry_match *match)
 {
-	const struct ipt_ecn_info *einfo =
-		(const struct ipt_ecn_info *)match->data;
-	
-	if (einfo->operation & IPT_ECN_OP_MATCH_ECE) {
-		if (einfo->invert & IPT_ECN_OP_MATCH_ECE)
+	const struct xt_ecn_info *einfo =
+		(const struct xt_ecn_info *)match->data;
+
+	if (einfo->operation & XT_ECN_OP_MATCH_ECE) {
+		if (einfo->invert & XT_ECN_OP_MATCH_ECE)
 			printf(" !");
 		printf(" --ecn-tcp-ece");
 	}
 
-	if (einfo->operation & IPT_ECN_OP_MATCH_CWR) {
-		if (einfo->invert & IPT_ECN_OP_MATCH_CWR)
+	if (einfo->operation & XT_ECN_OP_MATCH_CWR) {
+		if (einfo->invert & XT_ECN_OP_MATCH_CWR)
 			printf(" !");
 		printf(" --ecn-tcp-cwr");
 	}
 
-	if (einfo->operation & IPT_ECN_OP_MATCH_IP) {
-		if (einfo->invert & IPT_ECN_OP_MATCH_IP)
+	if (einfo->operation & XT_ECN_OP_MATCH_IP) {
+		if (einfo->invert & XT_ECN_OP_MATCH_IP)
 			printf(" !");
 		printf(" --ecn-ip-ect %d", einfo->ip_ect);
 	}
@@ -120,9 +121,9 @@ static void ecn_save(const void *ip, const struct xt_entry_match *match)
 static struct xtables_match ecn_mt_reg = {
 	.name          = "ecn",
 	.version       = XTABLES_VERSION,
-	.family        = NFPROTO_IPV4,
-	.size          = XT_ALIGN(sizeof(struct ipt_ecn_info)),
-	.userspacesize = XT_ALIGN(sizeof(struct ipt_ecn_info)),
+	.family        = NFPROTO_UNSPEC,
+	.size          = XT_ALIGN(sizeof(struct xt_ecn_info)),
+	.userspacesize = XT_ALIGN(sizeof(struct xt_ecn_info)),
 	.help          = ecn_help,
 	.print         = ecn_print,
 	.save          = ecn_save,
diff --git a/extensions/libipt_ecn.man b/extensions/libxt_ecn.man
index 7f806477..31c0a3e8 100644
--- a/extensions/libipt_ecn.man
+++ b/extensions/libxt_ecn.man
@@ -1,4 +1,4 @@
-This allows you to match the ECN bits of the IPv4 and TCP header.  ECN is the Explicit Congestion Notification mechanism as specified in RFC3168
+This allows you to match the ECN bits of the IPv4/IPv6 and TCP header.  ECN is the Explicit Congestion Notification mechanism as specified in RFC3168
 .TP
 [\fB!\fP] \fB\-\-ecn\-tcp\-cwr\fP
 This matches if the TCP ECN CWR (Congestion Window Received) bit is set.
@@ -7,5 +7,5 @@ This matches if the TCP ECN CWR (Congestion Window Received) bit is set.
 This matches if the TCP ECN ECE (ECN Echo) bit is set.
 .TP
 [\fB!\fP] \fB\-\-ecn\-ip\-ect\fP \fInum\fP
-This matches a particular IPv4 ECT (ECN-Capable Transport). You have to specify
+This matches a particular IPv4/IPv6 ECT (ECN-Capable Transport). You have to specify
 a number between `0' and `3'.
diff --git a/include/linux/netfilter/xt_ecn.h b/include/linux/netfilter/xt_ecn.h
new file mode 100644
index 00000000..c21cc280
--- /dev/null
+++ b/include/linux/netfilter/xt_ecn.h
@@ -0,0 +1,33 @@
+/* iptables module for matching the ECN header in IPv4 and TCP header
+ *
+ * (C) 2002 Harald Welte <laforge@netfilter.org>
+ *
+ * This software is distributed under GNU GPL v2, 1991
+*/
+#ifndef _XT_ECN_H
+#define _XT_ECN_H
+
+#include <linux/types.h>
+#include <linux/netfilter/xt_dscp.h>
+
+#define XT_ECN_IP_MASK	(~XT_DSCP_MASK)
+
+#define XT_ECN_OP_MATCH_IP	0x01
+#define XT_ECN_OP_MATCH_ECE	0x10
+#define XT_ECN_OP_MATCH_CWR	0x20
+
+#define XT_ECN_OP_MATCH_MASK	0xce
+
+/* match info */
+struct xt_ecn_info {
+	__u8 operation;
+	__u8 invert;
+	__u8 ip_ect;
+	union {
+		struct {
+			__u8 ect;
+		} tcp;
+	} proto;
+};
+
+#endif /* _XT_ECN_H */
diff --git a/include/linux/netfilter_ipv4/ipt_ecn.h b/include/linux/netfilter_ipv4/ipt_ecn.h
deleted file mode 100644
index eabf95fb..00000000
--- a/include/linux/netfilter_ipv4/ipt_ecn.h
+++ /dev/null
@@ -1,35 +0,0 @@
-/* iptables module for matching the ECN header in IPv4 and TCP header
- *
- * (C) 2002 Harald Welte <laforge@gnumonks.org>
- *
- * This software is distributed under GNU GPL v2, 1991
- * 
- * ipt_ecn.h,v 1.4 2002/08/05 19:39:00 laforge Exp
-*/
-#ifndef _IPT_ECN_H
-#define _IPT_ECN_H
-
-#include <linux/types.h>
-#include <linux/netfilter/xt_dscp.h>
-
-#define IPT_ECN_IP_MASK	(~XT_DSCP_MASK)
-
-#define IPT_ECN_OP_MATCH_IP	0x01
-#define IPT_ECN_OP_MATCH_ECE	0x10
-#define IPT_ECN_OP_MATCH_CWR	0x20
-
-#define IPT_ECN_OP_MATCH_MASK	0xce
-
-/* match info */
-struct ipt_ecn_info {
-	__u8 operation;
-	__u8 invert;
-	__u8 ip_ect;
-	union {
-		struct {
-			__u8 ect;
-		} tcp;
-	} proto;
-};
-
-#endif /* _IPT_ECN_H */