release/src-rt/linux/linux-2.6/net/ipv4/netfilter/ipt_MACSAVE.c

   1 /*
   2
   3         MACSAVE target
   4         Copyright (C) 2006 Jonathan Zarate
   5
   6         Licensed under GNU GPL v2 or later.
   7
   8 */
   9 #include <linux/module.h>
  10 #include <linux/skbuff.h>
  11 #include <linux/version.h>
  12 #include <linux/if_ether.h>
  13
  14 #include <net/netfilter/nf_conntrack.h>
  15 #include <linux/netfilter_ipv4/ip_tables.h>
  16 #include <linux/netfilter_ipv4/ipt_MACSAVE.h>
  17
  18 static unsigned int
  19 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,22)
  20 target(struct sk_buff **pskb,
  21        const struct net_device *in,
  22        const struct net_device *out,
  23        unsigned int hooknum,
  24        const struct xt_target *target,
  25        const void *targinfo)
  26 #elif LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28)
  27 target(struct sk_buff *skb,
  28        const struct net_device *in,
  29        const struct net_device *out,
  30        unsigned int hooknum,
  31        const struct xt_target *target,
  32        const void *targinfo)
  33 #else /* LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28) */
  34 target(struct sk_buff *skb,
  35        const struct xt_target_param *par)
  36 #endif
  37 {
  38 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28)
  39 //      const struct ipt_MACSAVE_target_info *info = targinfo;
  40 #else
  41 //      const struct ipt_MACSAVE_target_info *info = par->targinfo;
  42 #endif
  43 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,22)
  44         struct sk_buff *skb = *pskb;
  45 #endif
  46         struct nf_conn *ct;
  47         enum ip_conntrack_info ctinfo;
  48
  49         if ((skb_mac_header(skb) >= skb->head) && ((skb_mac_header(skb) + ETH_HLEN) <= skb->data)) {
  50                 ct = nf_ct_get(skb, &ctinfo);
  51                 if (ct) {
  52                         memcpy(ct->macsave, eth_hdr(skb)->h_source, sizeof(ct->macsave));
  53                 }
  54         }
  55         return IPT_CONTINUE;
  56 }
  57
  58 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
  59 static int
  60 checkentry(const char *tablename,
  61            const void *e,
  62            const struct xt_target *target,
  63            void *targinfo,
  64            unsigned int hook_mask)
  65 #elif LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28)
  66 static bool
  67 checkentry(const char *tablename,
  68            const void *e,
  69            const struct xt_target *target,
  70            void *targinfo,
  71            unsigned int hook_mask)
  72 #else /* LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28) */
  73 static bool
  74 checkentry(const struct xt_tgchk_param *par)
  75 #endif
  76 {
  77 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
  78         unsigned int hook_mask = par->hook_mask;
  79 #endif
  80         if (hook_mask & ~((1 << NF_IP_PRE_ROUTING) | (1 << NF_IP_FORWARD) | (1 << NF_IP_LOCAL_IN))) {
  81                 printk(KERN_ERR "MACSAVE: Valid only in PREROUTING, FORWARD and INPUT\n");
  82                 return 0;
  83         }
  84         return 1;
  85 }
  86
  87 static struct ipt_target macsave_target = {
  88         .name = "MACSAVE",
  89         .family = AF_INET,
  90         .target = target,
  91         .targetsize = sizeof(struct ipt_MACSAVE_target_info),
  92         .checkentry = checkentry,
  93         .me = THIS_MODULE,
  94 };
  95
  96 static int __init init(void)
  97 {
  98         return xt_register_target(&macsave_target);
  99 }
 100
 101 static void __exit fini(void)
 102 {
 103         xt_unregister_target(&macsave_target);
 104 }
 105
 106 module_init(init);
 107 module_exit(fini);
 108 MODULE_LICENSE("GPL");