tags 310585 + patch
thanks

hi,

attached an updated diff which should apply against
kernel-source-2.4.27, didnt test compile nor its functionality.

bye,
    - michael
diff -ruN kernel-source-2.4.27/Documentation/Configure.help 
kernel-source-2.4.27-ttl/Documentation/Configure.help
--- kernel-source-2.4.27/Documentation/Configure.help   2005-05-27 
10:48:40.000000000 +0200
+++ kernel-source-2.4.27-ttl/Documentation/Configure.help       2005-05-27 
10:49:32.000000000 +0200
@@ -3219,6 +3219,15 @@
   If you want to compile it as a module, say M here and read
   <file:Documentation/modules.txt>.  If unsure, say `N'.
 
+TTL target support
+CONFIG_IP_NF_TARGET_TTL
+  This option adds a `TTL' target, which enables the user to set
+  the TTL value or increment / decrement the TTL value by a given
+  amount.
+
+  If you want to compile it as a module, say M here and read
+  Documentation/modules.txt.  If unsure, say `N'.
+
 ipchains (2.2-style) support
 CONFIG_IP_NF_COMPAT_IPCHAINS
   This option places ipchains (with masquerading and redirection
diff -ruN kernel-source-2.4.27/include/linux/netfilter_ipv4/ipt_TTL.h 
kernel-source-2.4.27-ttl/include/linux/netfilter_ipv4/ipt_TTL.h
--- kernel-source-2.4.27/include/linux/netfilter_ipv4/ipt_TTL.h 1970-01-01 
01:00:00.000000000 +0100
+++ kernel-source-2.4.27-ttl/include/linux/netfilter_ipv4/ipt_TTL.h     
2005-05-27 10:49:31.000000000 +0200
@@ -0,0 +1,21 @@
+/* TTL modification module for IP tables
+ * (C) 2000 by Harald Welte <[EMAIL PROTECTED]> */
+
+#ifndef _IPT_TTL_H
+#define _IPT_TTL_H
+
+enum {
+       IPT_TTL_SET = 0,
+       IPT_TTL_INC,
+       IPT_TTL_DEC
+};
+
+#define IPT_TTL_MAXMODE        IPT_TTL_DEC
+
+struct ipt_TTL_info {
+       u_int8_t        mode;
+       u_int8_t        ttl;
+};
+
+
+#endif
diff -ruN kernel-source-2.4.27/net/ipv4/netfilter/Config.in 
kernel-source-2.4.27-ttl/net/ipv4/netfilter/Config.in
--- kernel-source-2.4.27/net/ipv4/netfilter/Config.in   2005-05-27 
10:48:40.000000000 +0200
+++ kernel-source-2.4.27-ttl/net/ipv4/netfilter/Config.in       2005-05-27 
10:49:32.000000000 +0200
@@ -106,6 +106,7 @@
     dep_tristate '    MARK target support' CONFIG_IP_NF_TARGET_MARK 
$CONFIG_IP_NF_MANGLE
   fi
   dep_tristate '  LOG target support' CONFIG_IP_NF_TARGET_LOG 
$CONFIG_IP_NF_IPTABLES
+  dep_tristate '  TTL target support' CONFIG_IP_NF_TARGET_TTL 
$CONFIG_IP_NF_IPTABLES
   dep_tristate '  ULOG target support' CONFIG_IP_NF_TARGET_ULOG 
$CONFIG_IP_NF_IPTABLES
   dep_tristate '  TCPMSS target support' CONFIG_IP_NF_TARGET_TCPMSS 
$CONFIG_IP_NF_IPTABLES
 fi
diff -ruN kernel-source-2.4.27/net/ipv4/netfilter/Makefile 
kernel-source-2.4.27-ttl/net/ipv4/netfilter/Makefile
--- kernel-source-2.4.27/net/ipv4/netfilter/Makefile    2005-05-27 
10:48:40.000000000 +0200
+++ kernel-source-2.4.27-ttl/net/ipv4/netfilter/Makefile        2005-05-27 
10:49:32.000000000 +0200
@@ -98,6 +98,7 @@
 obj-$(CONFIG_IP_NF_TARGET_REDIRECT) += ipt_REDIRECT.o
 obj-$(CONFIG_IP_NF_NAT_SNMP_BASIC) += ip_nat_snmp_basic.o
 obj-$(CONFIG_IP_NF_TARGET_LOG) += ipt_LOG.o
+obj-$(CONFIG_IP_NF_TARGET_TTL) += ipt_TTL.o
 obj-$(CONFIG_IP_NF_TARGET_ULOG) += ipt_ULOG.o
 obj-$(CONFIG_IP_NF_TARGET_TCPMSS) += ipt_TCPMSS.o
 
diff -ruN kernel-source-2.4.27/net/ipv4/netfilter/ipt_TTL.c 
kernel-source-2.4.27-ttl/net/ipv4/netfilter/ipt_TTL.c
--- kernel-source-2.4.27/net/ipv4/netfilter/ipt_TTL.c   1970-01-01 
01:00:00.000000000 +0100
+++ kernel-source-2.4.27-ttl/net/ipv4/netfilter/ipt_TTL.c       2005-05-27 
10:49:31.000000000 +0200
@@ -0,0 +1,110 @@
+/* TTL modification target for IP tables
+ * (C) 2000 by Harald Welte <[EMAIL PROTECTED]>
+ *
+ * Version: 1.2
+ *
+ * This software is distributed under the terms of GNU GPL
+ */
+
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/ip.h>
+#include <net/checksum.h>
+
+#include <linux/netfilter_ipv4/ip_tables.h>
+#include <linux/netfilter_ipv4/ipt_TTL.h>
+
+MODULE_AUTHOR("Harald Welte <[EMAIL PROTECTED]>");
+MODULE_DESCRIPTION("IP tables TTL modification module");
+MODULE_LICENSE("GPL");
+
+static unsigned int ipt_ttl_target(struct sk_buff **pskb, unsigned int hooknum,
+               const struct net_device *in, const struct net_device *out,
+               const void *targinfo, void *userinfo)
+{
+       struct iphdr *iph = (*pskb)->nh.iph;
+       const struct ipt_TTL_info *info = targinfo;
+       u_int16_t diffs[2];
+       int new_ttl;
+                        
+       switch (info->mode) {
+               case IPT_TTL_SET:
+                       new_ttl = info->ttl;
+                       break;
+               case IPT_TTL_INC:
+                       new_ttl = iph->ttl + info->ttl;
+                       if (new_ttl > 255)
+                               new_ttl = 255;
+                       break;
+               case IPT_TTL_DEC:
+                       new_ttl = iph->ttl + info->ttl;
+                       if (new_ttl < 0)
+                               new_ttl = 0;
+                       break;
+               default:
+                       new_ttl = iph->ttl;
+                       break;
+       }
+
+       if (new_ttl != iph->ttl) {
+               diffs[0] = htons(((unsigned)iph->ttl) << 8) ^ 0xFFFF;
+               iph->ttl = new_ttl;
+               diffs[1] = htons(((unsigned)iph->ttl) << 8);
+               iph->check = csum_fold(csum_partial((char *)diffs,
+                                                   sizeof(diffs),
+                                                   iph->check^0xFFFF));
+                                                                               
                (*pskb)->nfcache |= NFC_ALTERED;
+       }
+
+       return IPT_CONTINUE;
+}
+
+static int ipt_ttl_checkentry(const char *tablename,
+               const struct ipt_entry *e,
+               void *targinfo,
+               unsigned int targinfosize,
+               unsigned int hook_mask)
+{
+       struct ipt_TTL_info *info = targinfo;
+
+       if (targinfosize != IPT_ALIGN(sizeof(struct ipt_TTL_info))) {
+               printk(KERN_WARNING "TTL: targinfosize %u != %Zu\n",
+                               targinfosize,
+                               IPT_ALIGN(sizeof(struct ipt_TTL_info)));
+               return 0;       
+       }       
+
+       if (strcmp(tablename, "mangle")) {
+               printk(KERN_WARNING "TTL: can only be called from \"mangle\" 
table, not \"%s\"\n", tablename);
+               return 0;
+       }
+
+       if (info->mode > IPT_TTL_MAXMODE) {
+               printk(KERN_WARNING "TTL: invalid or unknown Mode %u\n", 
+                       info->mode);
+               return 0;
+       }
+
+       if ((info->mode != IPT_TTL_SET) && (info->ttl == 0)) {
+               printk(KERN_WARNING "TTL: increment/decrement doesn't make 
sense with value 0\n");
+               return 0;
+       }
+       
+       return 1;
+}
+
+static struct ipt_target ipt_TTL = { { NULL, NULL }, "TTL", 
+       ipt_ttl_target, ipt_ttl_checkentry, NULL, THIS_MODULE };
+
+static int __init init(void)
+{
+       return ipt_register_target(&ipt_TTL);
+}
+
+static void __exit fini(void)
+{
+       ipt_unregister_target(&ipt_TTL);
+}
+
+module_init(init);
+module_exit(fini);

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