batman-adv: Add wrapper for ARP reply creation

Removing duplicate code.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c
index cbb4f3232a7b280be167bd200c27d33f9f953fb8..49576c5a3fe306a42c28c3901d2b2c6cce7d0b8e 100644 (file)
--- a/net/batman-adv/distributed-arp-table.c
+++ b/net/batman-adv/distributed-arp-table.c
@@ -948,6 +948,41 @@ static unsigned short batadv_dat_get_vid(struct sk_buff *skb, int *hdr_size)
        return vid;
 }
 
+/**
+ * batadv_dat_arp_create_reply - create an ARP Reply
+ * @bat_priv: the bat priv with all the soft interface information
+ * @ip_src: ARP sender IP
+ * @ip_dst: ARP target IP
+ * @hw_src: Ethernet source and ARP sender MAC
+ * @hw_dst: Ethernet destination and ARP target MAC
+ * @vid: VLAN identifier (optional, set to zero otherwise)
+ *
+ * Creates an ARP Reply from the given values, optionally encapsulated in a
+ * VLAN header.
+ *
+ * Return: An skb containing an ARP Reply.
+ */
+static struct sk_buff *
+batadv_dat_arp_create_reply(struct batadv_priv *bat_priv, __be32 ip_src,
+                           __be32 ip_dst, u8 *hw_src, u8 *hw_dst,
+                           unsigned short vid)
+{
+       struct sk_buff *skb;
+
+       skb = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_dst, bat_priv->soft_iface,
+                        ip_src, hw_dst, hw_src, hw_dst);
+       if (!skb)
+               return NULL;
+
+       skb_reset_mac_header(skb);
+
+       if (vid & BATADV_VLAN_HAS_TAG)
+               skb = vlan_insert_tag(skb, htons(ETH_P_8021Q),
+                                     vid & VLAN_VID_MASK);
+
+       return skb;
+}
+
 /**
  * batadv_dat_snoop_outgoing_arp_request - snoop the ARP request and try to
  * answer using DAT
@@ -1005,20 +1040,12 @@ bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv,
                        goto out;
                }
 
-               skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src,
-                                    bat_priv->soft_iface, ip_dst, hw_src,
-                                    dat_entry->mac_addr, hw_src);
+               skb_new = batadv_dat_arp_create_reply(bat_priv, ip_dst, ip_src,
+                                                     dat_entry->mac_addr,
+                                                     hw_src, vid);
                if (!skb_new)
                        goto out;
 
-               if (vid & BATADV_VLAN_HAS_TAG) {
-                       skb_new = vlan_insert_tag(skb_new, htons(ETH_P_8021Q),
-                                                 vid & VLAN_VID_MASK);
-                       if (!skb_new)
-                               goto out;
-               }
-
-               skb_reset_mac_header(skb_new);
                skb_new->protocol = eth_type_trans(skb_new,
                                                   bat_priv->soft_iface);
                bat_priv->stats.rx_packets++;
@@ -1081,25 +1108,11 @@ bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv,
        if (!dat_entry)
                goto out;
 
-       skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src,
-                            bat_priv->soft_iface, ip_dst, hw_src,
-                            dat_entry->mac_addr, hw_src);
-
+       skb_new = batadv_dat_arp_create_reply(bat_priv, ip_dst, ip_src,
+                                             dat_entry->mac_addr, hw_src, vid);
        if (!skb_new)
                goto out;
 
-       /* the rest of the TX path assumes that the mac_header offset pointing
-        * to the inner Ethernet header has been set, therefore reset it now.
-        */
-       skb_reset_mac_header(skb_new);
-
-       if (vid & BATADV_VLAN_HAS_TAG) {
-               skb_new = vlan_insert_tag(skb_new, htons(ETH_P_8021Q),
-                                         vid & VLAN_VID_MASK);
-               if (!skb_new)
-                       goto out;
-       }
-
        /* To preserve backwards compatibility, the node has choose the outgoing
         * format based on the incoming request packet type. The assumption is
         * that a node not using the 4addr packet format doesn't support it.