ip: introduce ip_is_fragment helper inline function

There are enough instances of this:

    iph->frag_off & htons(IP_MF | IP_OFFSET)

that a helper function is probably warranted.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

12 files changed, 16 insertions, 17 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 8efe850..6b6ef14 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2532,7 +2532,7 @@ __u32 __skb_get_rxhash(struct sk_buff *skb)
 			goto done;
 
 		ip = (const struct iphdr *) (skb->data + nhoff);
-		if (ip->frag_off & htons(IP_MF | IP_OFFSET))
+		if (ip_is_fragment(ip))
 			ip_proto = 0;
 		else
 			ip_proto = ip->protocol;
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index c8f48ef..073a9b0 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -165,7 +165,7 @@ int ip_call_ra_chain(struct sk_buff *skb)
 		    (!sk->sk_bound_dev_if ||
 		     sk->sk_bound_dev_if == dev->ifindex) &&
 		    net_eq(sock_net(sk), dev_net(dev))) {
-			if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
+			if (ip_is_fragment(ip_hdr(skb))) {
 				if (ip_defrag(skb, IP_DEFRAG_CALL_RA_CHAIN))
 					return 1;
 			}
@@ -256,7 +256,7 @@ int ip_local_deliver(struct sk_buff *skb)
 	 *	Reassemble IP fragments.
 	 */
 
-	if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
+	if (ip_is_fragment(ip_hdr(skb))) {
 		if (ip_defrag(skb, IP_DEFRAG_LOCAL_DELIVER))
 			return 0;
 	}
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index a8024ea..167da8b 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -489,7 +489,7 @@ int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
 
 		if (first_len - hlen > mtu ||
 		    ((first_len - hlen) & 7) ||
-		    (iph->frag_off & htons(IP_MF|IP_OFFSET)) ||
+		    ip_is_fragment(iph) ||
 		    skb_cloned(skb))
 			goto slow_path;
 
diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index ab7e554..ae93dd5 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -932,7 +932,7 @@ static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, str
 		goto drop;
 
 	/* Fragments are not supported */
-	if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
+	if (ip_is_fragment(h)) {
 		if (net_ratelimit())
 			printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
 			       "reply.\n");
diff --git a/net/ipv4/netfilter/nf_defrag_ipv4.c b/net/ipv4/netfilter/nf_defrag_ipv4.c
index f3a9b42..9bb1b8a 100644
--- a/net/ipv4/netfilter/nf_defrag_ipv4.c
+++ b/net/ipv4/netfilter/nf_defrag_ipv4.c
@@ -82,7 +82,7 @@ static unsigned int ipv4_conntrack_defrag(unsigned int hooknum,
 #endif
 #endif
 	/* Gather fragments. */
-	if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
+	if (ip_is_fragment(ip_hdr(skb))) {
 		enum ip_defrag_users user = nf_ct_defrag_user(hooknum, skb);
 		if (nf_ct_ipv4_gather_frags(skb, user))
 			return NF_STOLEN;
diff --git a/net/ipv4/netfilter/nf_nat_standalone.c b/net/ipv4/netfilter/nf_nat_standalone.c
index 483b76d..a6e606e 100644
--- a/net/ipv4/netfilter/nf_nat_standalone.c
+++ b/net/ipv4/netfilter/nf_nat_standalone.c
@@ -88,7 +88,7 @@ nf_nat_fn(unsigned int hooknum,
 
 	/* We never see fragments: conntrack defrags on pre-routing
 	   and local-out, and nf_nat_out protects post-routing. */
-	NF_CT_ASSERT(!(ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)));
+	NF_CT_ASSERT(!ip_is_fragment(ip_hdr(skb)));
 
 	ct = nf_ct_get(skb, &ctinfo);
 	/* Can't track?  It's not due to stress, or conntrack would
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index 981e43e..fc5368a 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -117,7 +117,7 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 	memset(fl4, 0, sizeof(struct flowi4));
 	fl4->flowi4_mark = skb->mark;
 
-	if (!(iph->frag_off & htons(IP_MF | IP_OFFSET))) {
+	if (!ip_is_fragment(iph)) {
 		switch (iph->protocol) {
 		case IPPROTO_UDP:
 		case IPPROTO_UDPLITE:
diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c
index e33d48c..4f77bb1 100644
--- a/net/netfilter/ipvs/ip_vs_core.c
+++ b/net/netfilter/ipvs/ip_vs_core.c
@@ -852,7 +852,7 @@ static int ip_vs_out_icmp(struct sk_buff *skb, int *related,
 	*related = 1;
 
 	/* reassemble IP fragments */
-	if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
+	if (ip_is_fragment(ip_hdr(skb))) {
 		if (ip_vs_gather_frags(skb, ip_vs_defrag_user(hooknum)))
 			return NF_STOLEN;
 	}
@@ -1156,8 +1156,7 @@ ip_vs_out(unsigned int hooknum, struct sk_buff *skb, int af)
 		ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
 	} else
 #endif
-		if (unlikely(ip_hdr(skb)->frag_off & htons(IP_MF|IP_OFFSET) &&
-			     !pp->dont_defrag)) {
+		if (unlikely(ip_is_fragment(ip_hdr(skb)) && !pp->dont_defrag)) {
 			if (ip_vs_gather_frags(skb,
 					       ip_vs_defrag_user(hooknum)))
 				return NF_STOLEN;
@@ -1310,7 +1309,7 @@ ip_vs_in_icmp(struct sk_buff *skb, int *related, unsigned int hooknum)
 	*related = 1;
 
 	/* reassemble IP fragments */
-	if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
+	if (ip_is_fragment(ip_hdr(skb))) {
 		if (ip_vs_gather_frags(skb, ip_vs_defrag_user(hooknum)))
 			return NF_STOLEN;
 	}
diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c
index 8ec0139..34533a5 100644
--- a/net/sched/cls_flow.c
+++ b/net/sched/cls_flow.c
@@ -121,7 +121,7 @@ static u32 flow_get_proto_src(struct sk_buff *skb)
 		if (!pskb_network_may_pull(skb, sizeof(*iph)))
 			break;
 		iph = ip_hdr(skb);
-		if (iph->frag_off & htons(IP_MF | IP_OFFSET))
+		if (ip_is_fragment(iph))
 			break;
 		poff = proto_ports_offset(iph->protocol);
 		if (poff >= 0 &&
@@ -163,7 +163,7 @@ static u32 flow_get_proto_dst(struct sk_buff *skb)
 		if (!pskb_network_may_pull(skb, sizeof(*iph)))
 			break;
 		iph = ip_hdr(skb);
-		if (iph->frag_off & htons(IP_MF | IP_OFFSET))
+		if (ip_is_fragment(iph))
 			break;
 		poff = proto_ports_offset(iph->protocol);
 		if (poff >= 0 &&
diff --git a/net/sched/cls_rsvp.h b/net/sched/cls_rsvp.h
index 402c44b..ed691b1 100644
--- a/net/sched/cls_rsvp.h
+++ b/net/sched/cls_rsvp.h
@@ -167,7 +167,7 @@ restart:
 	dst = &nhptr->daddr;
 	protocol = nhptr->protocol;
 	xprt = ((u8 *)nhptr) + (nhptr->ihl<<2);
-	if (nhptr->frag_off & htons(IP_MF | IP_OFFSET))
+	if (ip_is_fragment(nhptr))
 		return -1;
 #endif
 
diff --git a/net/sched/sch_choke.c b/net/sched/sch_choke.c
index 06afbae..3422b25 100644
--- a/net/sched/sch_choke.c
+++ b/net/sched/sch_choke.c
@@ -181,7 +181,7 @@ static bool choke_match_flow(struct sk_buff *skb1,
 		    ip1->saddr != ip2->saddr || ip1->daddr != ip2->daddr)
 			return false;
 
-		if ((ip1->frag_off | ip2->frag_off) & htons(IP_MF | IP_OFFSET))
+		if (ip_is_fragment(ip1) | ip_is_fragment(ip2))
 			ip_proto = 0;
 		off1 += ip1->ihl * 4;
 		off2 += ip2->ihl * 4;
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c
index b6ea6af..4536ee6 100644
--- a/net/sched/sch_sfq.c
+++ b/net/sched/sch_sfq.c
@@ -157,7 +157,7 @@ static unsigned int sfq_hash(struct sfq_sched_data *q, struct sk_buff *skb)
 		iph = ip_hdr(skb);
 		h = (__force u32)iph->daddr;
 		h2 = (__force u32)iph->saddr ^ iph->protocol;
-		if (iph->frag_off & htons(IP_MF | IP_OFFSET))
+		if (ip_is_fragment(iph))
 			break;
 		poff = proto_ports_offset(iph->protocol);
 		if (poff >= 0 &&