netfilter: Combine ipt_TTL and ip6t_HL source
authorJan Engelhardt <jengelh@medozas.de>
Wed, 18 Feb 2009 17:38:40 +0000 (18:38 +0100)
committerPatrick McHardy <kaber@trash.net>
Wed, 18 Feb 2009 17:38:40 +0000 (18:38 +0100)
Suggested by: James King <t.james.king@gmail.com>

Similarly to commit c9fd49680954714473d6cbd2546d6ff120f96840, merge
TTL and HL. Since HL does not depend on any IPv6-specific function,
no new module dependencies would arise.

With slight adjustments to the Kconfig help text.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
net/ipv4/netfilter/Kconfig
net/ipv4/netfilter/Makefile
net/ipv4/netfilter/ipt_TTL.c [deleted file]
net/ipv6/netfilter/Kconfig
net/ipv6/netfilter/Makefile
net/ipv6/netfilter/ip6t_HL.c [deleted file]
net/netfilter/Kconfig
net/netfilter/Makefile
net/netfilter/xt_HL.c [new file with mode: 0644]

index 3816e1dc9295a5a3763b122dc1884342647bc3d5..3ad9f43b4c45fe0a84c841fe90ff66249db50ae4 100644 (file)
@@ -322,21 +322,6 @@ config IP_NF_TARGET_ECN
 
          To compile it as a module, choose M here.  If unsure, say N.
 
-config IP_NF_TARGET_TTL
-       tristate  'TTL target support'
-       depends on IP_NF_MANGLE
-       depends on NETFILTER_ADVANCED
-       help
-         This option adds a `TTL' target, which enables the user to modify
-         the TTL value of the IP header.
-
-         While it is safe to decrement/lower the TTL, this target also enables
-         functionality to increment and set the TTL value of the IP header to
-         arbitrary values.  This is EXTREMELY DANGEROUS since you can easily
-         create immortal packets that loop forever on the network.
-
-         To compile it as a module, choose M here.  If unsure, say N.
-
 # raw + specific targets
 config IP_NF_RAW
        tristate  'raw table support (required for NOTRACK/TRACE)'
index 5f9b650d90fc5fde8ed1dc9386eefc195ba79c21..20b0c37155fb3b802c1fa899dcb753263db7d73a 100644 (file)
@@ -61,7 +61,6 @@ obj-$(CONFIG_IP_NF_TARGET_MASQUERADE) += ipt_MASQUERADE.o
 obj-$(CONFIG_IP_NF_TARGET_NETMAP) += ipt_NETMAP.o
 obj-$(CONFIG_IP_NF_TARGET_REDIRECT) += ipt_REDIRECT.o
 obj-$(CONFIG_IP_NF_TARGET_REJECT) += ipt_REJECT.o
-obj-$(CONFIG_IP_NF_TARGET_TTL) += ipt_TTL.o
 obj-$(CONFIG_IP_NF_TARGET_ULOG) += ipt_ULOG.o
 
 # generic ARP tables
diff --git a/net/ipv4/netfilter/ipt_TTL.c b/net/ipv4/netfilter/ipt_TTL.c
deleted file mode 100644 (file)
index 6d76aae..0000000
+++ /dev/null
@@ -1,97 +0,0 @@
-/* TTL modification target for IP tables
- * (C) 2000,2005 by Harald Welte <laforge@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/skbuff.h>
-#include <linux/ip.h>
-#include <net/checksum.h>
-
-#include <linux/netfilter/x_tables.h>
-#include <linux/netfilter_ipv4/ipt_TTL.h>
-
-MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
-MODULE_DESCRIPTION("Xtables: IPv4 TTL field modification target");
-MODULE_LICENSE("GPL");
-
-static unsigned int
-ttl_tg(struct sk_buff *skb, const struct xt_target_param *par)
-{
-       struct iphdr *iph;
-       const struct ipt_TTL_info *info = par->targinfo;
-       int new_ttl;
-
-       if (!skb_make_writable(skb, skb->len))
-               return NF_DROP;
-
-       iph = ip_hdr(skb);
-
-       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) {
-               csum_replace2(&iph->check, htons(iph->ttl << 8),
-                                          htons(new_ttl << 8));
-               iph->ttl = new_ttl;
-       }
-
-       return XT_CONTINUE;
-}
-
-static bool ttl_tg_check(const struct xt_tgchk_param *par)
-{
-       const struct ipt_TTL_info *info = par->targinfo;
-
-       if (info->mode > IPT_TTL_MAXMODE) {
-               printk(KERN_WARNING "ipt_TTL: invalid or unknown Mode %u\n",
-                       info->mode);
-               return false;
-       }
-       if (info->mode != IPT_TTL_SET && info->ttl == 0)
-               return false;
-       return true;
-}
-
-static struct xt_target ttl_tg_reg __read_mostly = {
-       .name           = "TTL",
-       .family         = NFPROTO_IPV4,
-       .target         = ttl_tg,
-       .targetsize     = sizeof(struct ipt_TTL_info),
-       .table          = "mangle",
-       .checkentry     = ttl_tg_check,
-       .me             = THIS_MODULE,
-};
-
-static int __init ttl_tg_init(void)
-{
-       return xt_register_target(&ttl_tg_reg);
-}
-
-static void __exit ttl_tg_exit(void)
-{
-       xt_unregister_target(&ttl_tg_reg);
-}
-
-module_init(ttl_tg_init);
-module_exit(ttl_tg_exit);
index 53ea512c46089bf286984250140835fa4fd15ded..6a42a968c4983dbd31a69ca70cba3c35af5c80c2 100644 (file)
@@ -170,23 +170,6 @@ config IP6_NF_MANGLE
 
          To compile it as a module, choose M here.  If unsure, say N.
 
-config IP6_NF_TARGET_HL
-       tristate  'HL (hoplimit) target support'
-       depends on IP6_NF_MANGLE
-       depends on NETFILTER_ADVANCED
-       help
-         This option adds a `HL' target, which enables the user to decrement
-         the hoplimit value of the IPv6 header or set it to a given (lower)
-         value.
-
-         While it is safe to decrement the hoplimit value, this option also
-         enables functionality to increment and set the hoplimit value of the
-         IPv6 header to arbitrary values.  This is EXTREMELY DANGEROUS since
-         you can easily create immortal packets that loop forever on the
-         network.
-
-         To compile it as a module, choose M here.  If unsure, say N.
-
 config IP6_NF_RAW
        tristate  'raw table support (required for TRACE)'
        depends on NETFILTER_ADVANCED
index 3f17c948eefb10113964b24ff45fed58ccfd86b2..61a4570d0ede4ee2dd919191bf3c126b58f87077 100644 (file)
@@ -27,6 +27,5 @@ obj-$(CONFIG_IP6_NF_MATCH_OPTS) += ip6t_hbh.o
 obj-$(CONFIG_IP6_NF_MATCH_RT) += ip6t_rt.o
 
 # targets
-obj-$(CONFIG_IP6_NF_TARGET_HL) += ip6t_HL.o
 obj-$(CONFIG_IP6_NF_TARGET_LOG) += ip6t_LOG.o
 obj-$(CONFIG_IP6_NF_TARGET_REJECT) += ip6t_REJECT.o
diff --git a/net/ipv6/netfilter/ip6t_HL.c b/net/ipv6/netfilter/ip6t_HL.c
deleted file mode 100644 (file)
index 27b5adf..0000000
+++ /dev/null
@@ -1,95 +0,0 @@
-/*
- * Hop Limit modification target for ip6tables
- * Maciej Soltysiak <solt@dns.toxicfilms.tv>
- * Based on HW's TTL module
- *
- * This software is distributed under the terms of GNU GPL
- */
-
-#include <linux/module.h>
-#include <linux/skbuff.h>
-#include <linux/ip.h>
-#include <linux/ipv6.h>
-
-#include <linux/netfilter/x_tables.h>
-#include <linux/netfilter_ipv6/ip6t_HL.h>
-
-MODULE_AUTHOR("Maciej Soltysiak <solt@dns.toxicfilms.tv>");
-MODULE_DESCRIPTION("Xtables: IPv6 Hop Limit field modification target");
-MODULE_LICENSE("GPL");
-
-static unsigned int
-hl_tg6(struct sk_buff *skb, const struct xt_target_param *par)
-{
-       struct ipv6hdr *ip6h;
-       const struct ip6t_HL_info *info = par->targinfo;
-       int new_hl;
-
-       if (!skb_make_writable(skb, skb->len))
-               return NF_DROP;
-
-       ip6h = ipv6_hdr(skb);
-
-       switch (info->mode) {
-               case IP6T_HL_SET:
-                       new_hl = info->hop_limit;
-                       break;
-               case IP6T_HL_INC:
-                       new_hl = ip6h->hop_limit + info->hop_limit;
-                       if (new_hl > 255)
-                               new_hl = 255;
-                       break;
-               case IP6T_HL_DEC:
-                       new_hl = ip6h->hop_limit - info->hop_limit;
-                       if (new_hl < 0)
-                               new_hl = 0;
-                       break;
-               default:
-                       new_hl = ip6h->hop_limit;
-                       break;
-       }
-
-       ip6h->hop_limit = new_hl;
-
-       return XT_CONTINUE;
-}
-
-static bool hl_tg6_check(const struct xt_tgchk_param *par)
-{
-       const struct ip6t_HL_info *info = par->targinfo;
-
-       if (info->mode > IP6T_HL_MAXMODE) {
-               printk(KERN_WARNING "ip6t_HL: invalid or unknown Mode %u\n",
-                       info->mode);
-               return false;
-       }
-       if (info->mode != IP6T_HL_SET && info->hop_limit == 0) {
-               printk(KERN_WARNING "ip6t_HL: increment/decrement doesn't "
-                       "make sense with value 0\n");
-               return false;
-       }
-       return true;
-}
-
-static struct xt_target hl_tg6_reg __read_mostly = {
-       .name           = "HL",
-       .family         = NFPROTO_IPV6,
-       .target         = hl_tg6,
-       .targetsize     = sizeof(struct ip6t_HL_info),
-       .table          = "mangle",
-       .checkentry     = hl_tg6_check,
-       .me             = THIS_MODULE
-};
-
-static int __init hl_tg6_init(void)
-{
-       return xt_register_target(&hl_tg6_reg);
-}
-
-static void __exit hl_tg6_exit(void)
-{
-       xt_unregister_target(&hl_tg6_reg);
-}
-
-module_init(hl_tg6_init);
-module_exit(hl_tg6_exit);
index c2bac9cd0cafe6861a43ae619a9087eeba8ed1d5..d99f29b7b98003a0cccf915a9657f5fab66240e4 100644 (file)
@@ -357,6 +357,21 @@ config NETFILTER_XT_TARGET_DSCP
 
          To compile it as a module, choose M here.  If unsure, say N.
 
+config NETFILTER_XT_TARGET_HL
+       tristate '"HL" hoplimit target support'
+       depends on IP_NF_MANGLE || IP6_NF_MANGLE
+       depends on NETFILTER_ADVANCED
+       ---help---
+       This option adds the "HL" (for IPv6) and "TTL" (for IPv4)
+       targets, which enable the user to change the
+       hoplimit/time-to-live value of the IP header.
+
+       While it is safe to decrement the hoplimit/TTL value, the
+       modules also allow to increment and set the hoplimit value of
+       the header to arbitrary values. This is EXTREMELY DANGEROUS
+       since you can easily create immortal packets that loop
+       forever on the network.
+
 config NETFILTER_XT_TARGET_MARK
        tristate '"MARK" target support'
        default m if NETFILTER_ADVANCED=n
index da3d909e053fba4098c938bf6196b502b4c046f0..6ebe0482265bed0cd5d9e9eaf72c42b47207c98f 100644 (file)
@@ -45,6 +45,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_CLASSIFY) += xt_CLASSIFY.o
 obj-$(CONFIG_NETFILTER_XT_TARGET_CONNMARK) += xt_CONNMARK.o
 obj-$(CONFIG_NETFILTER_XT_TARGET_CONNSECMARK) += xt_CONNSECMARK.o
 obj-$(CONFIG_NETFILTER_XT_TARGET_DSCP) += xt_DSCP.o
+obj-$(CONFIG_NETFILTER_XT_TARGET_HL) += xt_HL.o
 obj-$(CONFIG_NETFILTER_XT_TARGET_MARK) += xt_MARK.o
 obj-$(CONFIG_NETFILTER_XT_TARGET_NFLOG) += xt_NFLOG.o
 obj-$(CONFIG_NETFILTER_XT_TARGET_NFQUEUE) += xt_NFQUEUE.o
diff --git a/net/netfilter/xt_HL.c b/net/netfilter/xt_HL.c
new file mode 100644 (file)
index 0000000..10e789e
--- /dev/null
@@ -0,0 +1,171 @@
+/*
+ * TTL modification target for IP tables
+ * (C) 2000,2005 by Harald Welte <laforge@netfilter.org>
+ *
+ * Hop Limit modification target for ip6tables
+ * Maciej Soltysiak <solt@dns.toxicfilms.tv>
+ *
+ * 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/ip.h>
+#include <linux/ipv6.h>
+#include <net/checksum.h>
+
+#include <linux/netfilter/x_tables.h>
+#include <linux/netfilter_ipv4/ipt_TTL.h>
+#include <linux/netfilter_ipv6/ip6t_HL.h>
+
+MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
+MODULE_AUTHOR("Maciej Soltysiak <solt@dns.toxicfilms.tv>");
+MODULE_DESCRIPTION("Xtables: Hoplimit/TTL Limit field modification target");
+MODULE_LICENSE("GPL");
+
+static unsigned int
+ttl_tg(struct sk_buff *skb, const struct xt_target_param *par)
+{
+       struct iphdr *iph;
+       const struct ipt_TTL_info *info = par->targinfo;
+       int new_ttl;
+
+       if (!skb_make_writable(skb, skb->len))
+               return NF_DROP;
+
+       iph = ip_hdr(skb);
+
+       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) {
+               csum_replace2(&iph->check, htons(iph->ttl << 8),
+                                          htons(new_ttl << 8));
+               iph->ttl = new_ttl;
+       }
+
+       return XT_CONTINUE;
+}
+
+static unsigned int
+hl_tg6(struct sk_buff *skb, const struct xt_target_param *par)
+{
+       struct ipv6hdr *ip6h;
+       const struct ip6t_HL_info *info = par->targinfo;
+       int new_hl;
+
+       if (!skb_make_writable(skb, skb->len))
+               return NF_DROP;
+
+       ip6h = ipv6_hdr(skb);
+
+       switch (info->mode) {
+               case IP6T_HL_SET:
+                       new_hl = info->hop_limit;
+                       break;
+               case IP6T_HL_INC:
+                       new_hl = ip6h->hop_limit + info->hop_limit;
+                       if (new_hl > 255)
+                               new_hl = 255;
+                       break;
+               case IP6T_HL_DEC:
+                       new_hl = ip6h->hop_limit - info->hop_limit;
+                       if (new_hl < 0)
+                               new_hl = 0;
+                       break;
+               default:
+                       new_hl = ip6h->hop_limit;
+                       break;
+       }
+
+       ip6h->hop_limit = new_hl;
+
+       return XT_CONTINUE;
+}
+
+static bool ttl_tg_check(const struct xt_tgchk_param *par)
+{
+       const struct ipt_TTL_info *info = par->targinfo;
+
+       if (info->mode > IPT_TTL_MAXMODE) {
+               printk(KERN_WARNING "ipt_TTL: invalid or unknown Mode %u\n",
+                       info->mode);
+               return false;
+       }
+       if (info->mode != IPT_TTL_SET && info->ttl == 0)
+               return false;
+       return true;
+}
+
+static bool hl_tg6_check(const struct xt_tgchk_param *par)
+{
+       const struct ip6t_HL_info *info = par->targinfo;
+
+       if (info->mode > IP6T_HL_MAXMODE) {
+               printk(KERN_WARNING "ip6t_HL: invalid or unknown Mode %u\n",
+                       info->mode);
+               return false;
+       }
+       if (info->mode != IP6T_HL_SET && info->hop_limit == 0) {
+               printk(KERN_WARNING "ip6t_HL: increment/decrement doesn't "
+                       "make sense with value 0\n");
+               return false;
+       }
+       return true;
+}
+
+static struct xt_target hl_tg_reg[] __read_mostly = {
+       {
+               .name       = "TTL",
+               .revision   = 0,
+               .family     = NFPROTO_IPV4,
+               .target     = ttl_tg,
+               .targetsize = sizeof(struct ipt_TTL_info),
+               .table      = "mangle",
+               .checkentry = ttl_tg_check,
+               .me         = THIS_MODULE,
+       },
+       {
+               .name       = "HL",
+               .revision   = 0,
+               .family     = NFPROTO_IPV6,
+               .target     = hl_tg6,
+               .targetsize = sizeof(struct ip6t_HL_info),
+               .table      = "mangle",
+               .checkentry = hl_tg6_check,
+               .me         = THIS_MODULE,
+       },
+};
+
+static int __init hl_tg_init(void)
+{
+       return xt_register_targets(hl_tg_reg, ARRAY_SIZE(hl_tg_reg));
+}
+
+static void __exit hl_tg_exit(void)
+{
+       xt_unregister_targets(hl_tg_reg, ARRAY_SIZE(hl_tg_reg));
+}
+
+module_init(hl_tg_init);
+module_exit(hl_tg_exit);
+MODULE_ALIAS("ipt_TTL");
+MODULE_ALIAS("ip6t_HL");