[IPV4]: Add 'rtable' field in struct sk_buff to alias 'dst' and avoid casts

(Anonymous) unions can help us to avoid ugly casts.

A common cast it the (struct rtable *)skb->dst one.

Defining an union like  :
union {
     struct dst_entry *dst;
     struct rtable *rtable;
};
permits to use skb->rtable in place.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 4 deletions

diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index 8d9d929f6ce..1afef08f6c1 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -363,7 +363,7 @@ static int sctp_v4_addr_valid(union sctp_addr *addr,
                 return 0;
 
         /* Is this a broadcast address? */
-        if (skb && ((struct rtable *)skb->dst)->rt_flags & RTCF_BROADCAST)
+        if (skb && skb->rtable->rt_flags & RTCF_BROADCAST)
                 return 0;
 
         return 1;
@@ -539,7 +539,7 @@ static void sctp_v4_get_saddr(struct sctp_association *asoc,
 /* What interface did this skb arrive on? */
 static int sctp_v4_skb_iif(const struct sk_buff *skb)
 {
-        return ((struct rtable *)skb->dst)->rt_iif;
+        return skb->rtable->rt_iif;
 }
 
 /* Was this packet marked by Explicit Congestion Notification? */
@@ -828,8 +828,8 @@ static inline int sctp_v4_xmit(struct sk_buff *skb,
         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
                           "src:%u.%u.%u.%u, dst:%u.%u.%u.%u\n",
                           __FUNCTION__, skb, skb->len,
-                          NIPQUAD(((struct rtable *)skb->dst)->rt_src),
-                          NIPQUAD(((struct rtable *)skb->dst)->rt_dst));
+                          NIPQUAD(skb->rtable->rt_src),
+                          NIPQUAD(skb->rtable->rt_dst));
 
         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
         return ip_queue_xmit(skb, ipfragok);