Add the rt linux 4.1.3-rt3 as base

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

diff --git a/kernel/net/bridge/netfilter/ebt_arp.c b/kernel/net/bridge/netfilter/ebt_arp.c
new file mode 100644 (file)
index 0000000..cd457b8
--- /dev/null
+++ b/kernel/net/bridge/netfilter/ebt_arp.c
@@ -0,0 +1,140 @@
+/*
+ *  ebt_arp
+ *
+ *     Authors:
+ *     Bart De Schuymer <bdschuym@pandora.be>
+ *     Tim Gardner <timg@tpi.com>
+ *
+ *  April, 2002
+ *
+ */
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/module.h>
+#include <linux/netfilter/x_tables.h>
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_arp.h>
+
+static bool
+ebt_arp_mt(const struct sk_buff *skb, struct xt_action_param *par)
+{
+       const struct ebt_arp_info *info = par->matchinfo;
+       const struct arphdr *ah;
+       struct arphdr _arph;
+
+       ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph);
+       if (ah == NULL)
+               return false;
+       if (info->bitmask & EBT_ARP_OPCODE && FWINV(info->opcode !=
+          ah->ar_op, EBT_ARP_OPCODE))
+               return false;
+       if (info->bitmask & EBT_ARP_HTYPE && FWINV(info->htype !=
+          ah->ar_hrd, EBT_ARP_HTYPE))
+               return false;
+       if (info->bitmask & EBT_ARP_PTYPE && FWINV(info->ptype !=
+          ah->ar_pro, EBT_ARP_PTYPE))
+               return false;
+
+       if (info->bitmask & (EBT_ARP_SRC_IP | EBT_ARP_DST_IP | EBT_ARP_GRAT)) {
+               const __be32 *sap, *dap;
+               __be32 saddr, daddr;
+
+               if (ah->ar_pln != sizeof(__be32) || ah->ar_pro != htons(ETH_P_IP))
+                       return false;
+               sap = skb_header_pointer(skb, sizeof(struct arphdr) +
+                                       ah->ar_hln, sizeof(saddr),
+                                       &saddr);
+               if (sap == NULL)
+                       return false;
+               dap = skb_header_pointer(skb, sizeof(struct arphdr) +
+                                       2*ah->ar_hln+sizeof(saddr),
+                                       sizeof(daddr), &daddr);
+               if (dap == NULL)
+                       return false;
+               if (info->bitmask & EBT_ARP_SRC_IP &&
+                   FWINV(info->saddr != (*sap & info->smsk), EBT_ARP_SRC_IP))
+                       return false;
+               if (info->bitmask & EBT_ARP_DST_IP &&
+                   FWINV(info->daddr != (*dap & info->dmsk), EBT_ARP_DST_IP))
+                       return false;
+               if (info->bitmask & EBT_ARP_GRAT &&
+                   FWINV(*dap != *sap, EBT_ARP_GRAT))
+                       return false;
+       }
+
+       if (info->bitmask & (EBT_ARP_SRC_MAC | EBT_ARP_DST_MAC)) {
+               const unsigned char *mp;
+               unsigned char _mac[ETH_ALEN];
+               uint8_t verdict, i;
+
+               if (ah->ar_hln != ETH_ALEN || ah->ar_hrd != htons(ARPHRD_ETHER))
+                       return false;
+               if (info->bitmask & EBT_ARP_SRC_MAC) {
+                       mp = skb_header_pointer(skb, sizeof(struct arphdr),
+                                               sizeof(_mac), &_mac);
+                       if (mp == NULL)
+                               return false;
+                       verdict = 0;
+                       for (i = 0; i < 6; i++)
+                               verdict |= (mp[i] ^ info->smaddr[i]) &
+                                      info->smmsk[i];
+                       if (FWINV(verdict != 0, EBT_ARP_SRC_MAC))
+                               return false;
+               }
+
+               if (info->bitmask & EBT_ARP_DST_MAC) {
+                       mp = skb_header_pointer(skb, sizeof(struct arphdr) +
+                                               ah->ar_hln + ah->ar_pln,
+                                               sizeof(_mac), &_mac);
+                       if (mp == NULL)
+                               return false;
+                       verdict = 0;
+                       for (i = 0; i < 6; i++)
+                               verdict |= (mp[i] ^ info->dmaddr[i]) &
+                                       info->dmmsk[i];
+                       if (FWINV(verdict != 0, EBT_ARP_DST_MAC))
+                               return false;
+               }
+       }
+
+       return true;
+}
+
+static int ebt_arp_mt_check(const struct xt_mtchk_param *par)
+{
+       const struct ebt_arp_info *info = par->matchinfo;
+       const struct ebt_entry *e = par->entryinfo;
+
+       if ((e->ethproto != htons(ETH_P_ARP) &&
+          e->ethproto != htons(ETH_P_RARP)) ||
+          e->invflags & EBT_IPROTO)
+               return -EINVAL;
+       if (info->bitmask & ~EBT_ARP_MASK || info->invflags & ~EBT_ARP_MASK)
+               return -EINVAL;
+       return 0;
+}
+
+static struct xt_match ebt_arp_mt_reg __read_mostly = {
+       .name           = "arp",
+       .revision       = 0,
+       .family         = NFPROTO_BRIDGE,
+       .match          = ebt_arp_mt,
+       .checkentry     = ebt_arp_mt_check,
+       .matchsize      = sizeof(struct ebt_arp_info),
+       .me             = THIS_MODULE,
+};
+
+static int __init ebt_arp_init(void)
+{
+       return xt_register_match(&ebt_arp_mt_reg);
+}
+
+static void __exit ebt_arp_fini(void)
+{
+       xt_unregister_match(&ebt_arp_mt_reg);
+}
+
+module_init(ebt_arp_init);
+module_exit(ebt_arp_fini);
+MODULE_DESCRIPTION("Ebtables: ARP protocol packet match");
+MODULE_LICENSE("GPL");