Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / net / bridge / netfilter / ebt_snat.c

diff --git a/kernel/net/bridge/netfilter/ebt_snat.c b/kernel/net/bridge/netfilter/ebt_snat.c
new file mode 100644 (file)
index 0000000..e56ccd0
--- /dev/null
+++ b/kernel/net/bridge/netfilter/ebt_snat.c
@@ -0,0 +1,87 @@
+/*
+ *  ebt_snat
+ *
+ *     Authors:
+ *     Bart De Schuymer <bdschuym@pandora.be>
+ *
+ *  June, 2002
+ *
+ */
+#include <linux/module.h>
+#include <net/sock.h>
+#include <linux/if_arp.h>
+#include <net/arp.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/x_tables.h>
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_nat.h>
+
+static unsigned int
+ebt_snat_tg(struct sk_buff *skb, const struct xt_action_param *par)
+{
+       const struct ebt_nat_info *info = par->targinfo;
+
+       if (!skb_make_writable(skb, 0))
+               return EBT_DROP;
+
+       ether_addr_copy(eth_hdr(skb)->h_source, info->mac);
+       if (!(info->target & NAT_ARP_BIT) &&
+           eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) {
+               const struct arphdr *ap;
+               struct arphdr _ah;
+
+               ap = skb_header_pointer(skb, 0, sizeof(_ah), &_ah);
+               if (ap == NULL)
+                       return EBT_DROP;
+               if (ap->ar_hln != ETH_ALEN)
+                       goto out;
+               if (skb_store_bits(skb, sizeof(_ah), info->mac, ETH_ALEN))
+                       return EBT_DROP;
+       }
+out:
+       return info->target | ~EBT_VERDICT_BITS;
+}
+
+static int ebt_snat_tg_check(const struct xt_tgchk_param *par)
+{
+       const struct ebt_nat_info *info = par->targinfo;
+       int tmp;
+
+       tmp = info->target | ~EBT_VERDICT_BITS;
+       if (BASE_CHAIN && tmp == EBT_RETURN)
+               return -EINVAL;
+
+       if (tmp < -NUM_STANDARD_TARGETS || tmp >= 0)
+               return -EINVAL;
+       tmp = info->target | EBT_VERDICT_BITS;
+       if ((tmp & ~NAT_ARP_BIT) != ~NAT_ARP_BIT)
+               return -EINVAL;
+       return 0;
+}
+
+static struct xt_target ebt_snat_tg_reg __read_mostly = {
+       .name           = "snat",
+       .revision       = 0,
+       .family         = NFPROTO_BRIDGE,
+       .table          = "nat",
+       .hooks          = (1 << NF_BR_NUMHOOKS) | (1 << NF_BR_POST_ROUTING),
+       .target         = ebt_snat_tg,
+       .checkentry     = ebt_snat_tg_check,
+       .targetsize     = sizeof(struct ebt_nat_info),
+       .me             = THIS_MODULE,
+};
+
+static int __init ebt_snat_init(void)
+{
+       return xt_register_target(&ebt_snat_tg_reg);
+}
+
+static void __exit ebt_snat_fini(void)
+{
+       xt_unregister_target(&ebt_snat_tg_reg);
+}
+
+module_init(ebt_snat_init);
+module_exit(ebt_snat_fini);
+MODULE_DESCRIPTION("Ebtables: Source MAC address translation");
+MODULE_LICENSE("GPL");