ipv4: rename ip_options_echo to __ip_options_echo()

ip_options_echo() assumes struct ip_options is provided in &IPCB(skb)->opt
Lets break this assumption, but provide a helper to not change all call points.

ip_send_unicast_reply() gets a new struct ip_options pointer.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip.h b/include/net/ip.h
index fcd9068..0bb6207 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -180,8 +180,10 @@
 	return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
 }
 
-void ip_send_unicast_reply(struct net *net, struct sk_buff *skb, __be32 daddr,
-			   __be32 saddr, const struct ip_reply_arg *arg,
+void ip_send_unicast_reply(struct net *net, struct sk_buff *skb,
+			   const struct ip_options *sopt,
+			   __be32 daddr, __be32 saddr,
+			   const struct ip_reply_arg *arg,
 			   unsigned int len);
 
 #define IP_INC_STATS(net, field)	SNMP_INC_STATS64((net)->mib.ip_statistics, field)
@@ -511,7 +513,14 @@
  
 void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
 		      __be32 daddr, struct rtable *rt, int is_frag);
-int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb);
+
+int __ip_options_echo(struct ip_options *dopt, struct sk_buff *skb,
+		      const struct ip_options *sopt);
+static inline int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb)
+{
+	return __ip_options_echo(dopt, skb, &IPCB(skb)->opt);
+}
+
 void ip_options_fragment(struct sk_buff *skb);
 int ip_options_compile(struct net *net, struct ip_options *opt,
 		       struct sk_buff *skb);