iptables: unbreak build without ipv6 support

From b5bfbb9fcac3d4c87bcf6da55ed40d63d456017d Mon Sep 17 00:00:00 2001

From: Peter Korsgaard <jacmet@sunsite.dk>

Date: Fri, 22 Jul 2011 07:19:09 +0200

Subject: [PATCH] libxt_TCPMSS.c: unbreak build without ipv6 after ea2a02f7

ea2a02f7 (libxt_TCPMSS: use guided option parser) added an netinet/ip6.h

include, which is not available on systems without ipv6.

The ip.h / ipv6.h includes are only used to know the size of struct

iphdr / ip6_hdr, so simply hardcode those instead.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

---

 extensions/libxt_TCPMSS.c |   13 +++++++------

 1 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/extensions/libxt_TCPMSS.c b/extensions/libxt_TCPMSS.c

index 2266326..310dd17 100644

--- a/extensions/libxt_TCPMSS.c

+++ b/extensions/libxt_TCPMSS.c

@@ -4,8 +4,6 @@

 */

 #include <stdio.h>

 #include <xtables.h>

-#include <netinet/ip.h>

-#include <netinet/ip6.h>

 #include <linux/netfilter/xt_TCPMSS.h>

 enum {

@@ -13,6 +11,9 @@ enum {

 	O_CLAMP_MSS,

 };

+#define IPHDRSIZE	20	/* sizeof(struct iphdr) */

+#define IP6HDRSIZE	40	/* sizeof(struct ip6_hdr) */

+

 struct mssinfo {

 	struct xt_entry_target t;

 	struct xt_tcpmss_info mss;

@@ -29,17 +30,17 @@ hdrsize);

 static void TCPMSS_help(void)

 {

-	__TCPMSS_help(sizeof(struct iphdr));

+	__TCPMSS_help(IPHDRSIZE);

 }

 static void TCPMSS_help6(void)

 {

-	__TCPMSS_help(sizeof(struct ip6_hdr));

+	__TCPMSS_help(IP6HDRSIZE);

 }

 static const struct xt_option_entry TCPMSS4_opts[] = {

 	{.name = "set-mss", .id = O_SET_MSS, .type = XTTYPE_UINT16,

-	 .min = 0, .max = UINT16_MAX - sizeof(struct iphdr),

+	 .min = 0, .max = UINT16_MAX - IPHDRSIZE,

 	 .flags = XTOPT_PUT, XTOPT_POINTER(struct xt_tcpmss_info, mss)},

 	{.name = "clamp-mss-to-pmtu", .id = O_CLAMP_MSS, .type = XTTYPE_NONE},

 	XTOPT_TABLEEND,

@@ -47,7 +48,7 @@ static const struct xt_option_entry TCPMSS4_opts[] = {

 static const struct xt_option_entry TCPMSS6_opts[] = {

 	{.name = "set-mss", .id = O_SET_MSS, .type = XTTYPE_UINT16,

-	 .min = 0, .max = UINT16_MAX - sizeof(struct ip6_hdr),

+	 .min = 0, .max = UINT16_MAX - IP6HDRSIZE,

 	 .flags = XTOPT_PUT, XTOPT_POINTER(struct xt_tcpmss_info, mss)},

 	{.name = "clamp-mss-to-pmtu", .id = O_CLAMP_MSS, .type = XTTYPE_NONE},

 	XTOPT_TABLEEND,

-- 

1.7.5.4