ipv4: Pass flow keys down into datagram packet building engine.

This way ip_output.c no longer needs rt->rt_{src,dst}.

We already have these keys sitting, ready and waiting, on the stack or
in a socket structure.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 36 insertions, 38 deletions

diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index cfeca3c2152..be5cc8d04c0 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -290,6 +290,7 @@ static int icmp_glue_bits(void *from, char *to, int offset, int len, int odd,
 }
 
 static void icmp_push_reply(struct icmp_bxm *icmp_param,
+			    struct flowi4 *fl4,
 			    struct ipcm_cookie *ipc, struct rtable **rt)
 {
 	struct sock *sk;
@@ -315,7 +316,7 @@ static void icmp_push_reply(struct icmp_bxm *icmp_param,
 						 icmp_param->head_len, csum);
 		icmph->checksum = csum_fold(csum);
 		skb->ip_summed = CHECKSUM_NONE;
-		ip_push_pending_frames(sk);
+		ip_push_pending_frames(sk, fl4);
 	}
 }
 
@@ -328,6 +329,7 @@ static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb)
 	struct ipcm_cookie ipc;
 	struct rtable *rt = skb_rtable(skb);
 	struct net *net = dev_net(rt->dst.dev);
+	struct flowi4 fl4;
 	struct sock *sk;
 	struct inet_sock *inet;
 	__be32 daddr;
@@ -351,57 +353,52 @@ static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb)
 		if (ipc.opt->opt.srr)
 			daddr = icmp_param->replyopts.opt.opt.faddr;
 	}
-	{
-		struct flowi4 fl4 = {
-			.daddr = daddr,
-			.saddr = rt->rt_spec_dst,
-			.flowi4_tos = RT_TOS(ip_hdr(skb)->tos),
-			.flowi4_proto = IPPROTO_ICMP,
-		};
-		security_skb_classify_flow(skb, flowi4_to_flowi(&fl4));
-		rt = ip_route_output_key(net, &fl4);
-		if (IS_ERR(rt))
-			goto out_unlock;
-	}
+	memset(&fl4, 0, sizeof(fl4));
+	fl4.daddr = daddr;
+	fl4.saddr = rt->rt_spec_dst;
+	fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos);
+	fl4.flowi4_proto = IPPROTO_ICMP;
+	security_skb_classify_flow(skb, flowi4_to_flowi(&fl4));
+	rt = ip_route_output_key(net, &fl4);
+	if (IS_ERR(rt))
+		goto out_unlock;
 	if (icmpv4_xrlim_allow(net, rt, icmp_param->data.icmph.type,
 			       icmp_param->data.icmph.code))
-		icmp_push_reply(icmp_param, &ipc, &rt);
+		icmp_push_reply(icmp_param, &fl4, &ipc, &rt);
 	ip_rt_put(rt);
 out_unlock:
 	icmp_xmit_unlock(sk);
 }
 
-static struct rtable *icmp_route_lookup(struct net *net, struct sk_buff *skb_in,
+static struct rtable *icmp_route_lookup(struct net *net,
+					struct flowi4 *fl4,
+					struct sk_buff *skb_in,
 					const struct iphdr *iph,
 					__be32 saddr, u8 tos,
 					int type, int code,
 					struct icmp_bxm *param)
 {
-	struct flowi4 fl4 = {
-		.daddr = (param->replyopts.opt.opt.srr ?
-			  param->replyopts.opt.opt.faddr : iph->saddr),
-		.saddr = saddr,
-		.flowi4_tos = RT_TOS(tos),
-		.flowi4_proto = IPPROTO_ICMP,
-		.fl4_icmp_type = type,
-		.fl4_icmp_code = code,
-	};
 	struct rtable *rt, *rt2;
 	int err;
 
-	security_skb_classify_flow(skb_in, flowi4_to_flowi(&fl4));
-	rt = __ip_route_output_key(net, &fl4);
+	memset(fl4, 0, sizeof(*fl4));
+	fl4->daddr = (param->replyopts.opt.opt.srr ?
+		      param->replyopts.opt.opt.faddr : iph->saddr);
+	fl4->saddr = saddr;
+	fl4->flowi4_tos = RT_TOS(tos);
+	fl4->flowi4_proto = IPPROTO_ICMP;
+	fl4->fl4_icmp_type = type;
+	fl4->fl4_icmp_code = code;
+	security_skb_classify_flow(skb_in, flowi4_to_flowi(fl4));
+	rt = __ip_route_output_key(net, fl4);
 	if (IS_ERR(rt))
 		return rt;
 
 	/* No need to clone since we're just using its address. */
 	rt2 = rt;
 
-	if (!fl4.saddr)
-		fl4.saddr = rt->rt_src;
-
 	rt = (struct rtable *) xfrm_lookup(net, &rt->dst,
-					   flowi4_to_flowi(&fl4), NULL, 0);
+					   flowi4_to_flowi(fl4), NULL, 0);
 	if (!IS_ERR(rt)) {
 		if (rt != rt2)
 			return rt;
@@ -410,19 +407,19 @@ static struct rtable *icmp_route_lookup(struct net *net, struct sk_buff *skb_in,
 	} else
 		return rt;
 
-	err = xfrm_decode_session_reverse(skb_in, flowi4_to_flowi(&fl4), AF_INET);
+	err = xfrm_decode_session_reverse(skb_in, flowi4_to_flowi(fl4), AF_INET);
 	if (err)
 		goto relookup_failed;
 
-	if (inet_addr_type(net, fl4.saddr) == RTN_LOCAL) {
-		rt2 = __ip_route_output_key(net, &fl4);
+	if (inet_addr_type(net, fl4->saddr) == RTN_LOCAL) {
+		rt2 = __ip_route_output_key(net, fl4);
 		if (IS_ERR(rt2))
 			err = PTR_ERR(rt2);
 	} else {
 		struct flowi4 fl4_2 = {};
 		unsigned long orefdst;
 
-		fl4_2.daddr = fl4.saddr;
+		fl4_2.daddr = fl4->saddr;
 		rt2 = ip_route_output_key(net, &fl4_2);
 		if (IS_ERR(rt2)) {
 			err = PTR_ERR(rt2);
@@ -430,7 +427,7 @@ static struct rtable *icmp_route_lookup(struct net *net, struct sk_buff *skb_in,
 		}
 		/* Ugh! */
 		orefdst = skb_in->_skb_refdst; /* save old refdst */
-		err = ip_route_input(skb_in, fl4.daddr, fl4.saddr,
+		err = ip_route_input(skb_in, fl4->daddr, fl4->saddr,
 				     RT_TOS(tos), rt2->dst.dev);
 
 		dst_release(&rt2->dst);
@@ -442,7 +439,7 @@ static struct rtable *icmp_route_lookup(struct net *net, struct sk_buff *skb_in,
 		goto relookup_failed;
 
 	rt2 = (struct rtable *) xfrm_lookup(net, &rt2->dst,
-					    flowi4_to_flowi(&fl4), NULL,
+					    flowi4_to_flowi(fl4), NULL,
 					    XFRM_LOOKUP_ICMP);
 	if (!IS_ERR(rt2)) {
 		dst_release(&rt->dst);
@@ -481,6 +478,7 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info)
 	struct icmp_bxm icmp_param;
 	struct rtable *rt = skb_rtable(skb_in);
 	struct ipcm_cookie ipc;
+	struct flowi4 fl4;
 	__be32 saddr;
 	u8  tos;
 	struct net *net;
@@ -599,7 +597,7 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info)
 	ipc.opt = &icmp_param.replyopts.opt;
 	ipc.tx_flags = 0;
 
-	rt = icmp_route_lookup(net, skb_in, iph, saddr, tos,
+	rt = icmp_route_lookup(net, &fl4, skb_in, iph, saddr, tos,
 			       type, code, &icmp_param);
 	if (IS_ERR(rt))
 		goto out_unlock;
@@ -620,7 +618,7 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info)
 		icmp_param.data_len = room;
 	icmp_param.head_len = sizeof(struct icmphdr);
 
-	icmp_push_reply(&icmp_param, &ipc, &rt);
+	icmp_push_reply(&icmp_param, &fl4, &ipc, &rt);
 ende:
 	ip_rt_put(rt);
 out_unlock: