[IPV4]: Keep fragment queues private to each user.

ChangeSet 1.1521.1.59, 2005/01/26 22:04:53-08:00, [email protected]

	[IPV4]: Keep fragment queues private to each user.
	
	Signed-off-by: Patrick McHardy <[email protected]>
	Signed-off-by: David S. Miller <[email protected]>



 include/linux/netfilter_ipv4/ip_conntrack.h  |    3 --
 include/net/ip.h                             |   16 ++++++++++---
 net/ipv4/ip_fragment.c                       |   32 ++++++++++-----------------
 net/ipv4/ip_input.c                          |    4 +--
 net/ipv4/ipvs/ip_vs_core.c                   |    6 ++---
 net/ipv4/netfilter/ip_conntrack_core.c       |   16 +++++--------
 net/ipv4/netfilter/ip_conntrack_standalone.c |    7 -----
 net/ipv4/netfilter/ip_nat_standalone.c       |    2 -
 net/netsyms.c                                |    1 
 9 files changed, 39 insertions(+), 48 deletions(-)


diff -Nru a/include/linux/netfilter_ipv4/ip_conntrack.h b/include/linux/netfilter_ipv4/ip_conntrack.h
--- a/include/linux/netfilter_ipv4/ip_conntrack.h	2005-02-01 16:04:11 -08:00
+++ b/include/linux/netfilter_ipv4/ip_conntrack.h	2005-02-01 16:04:11 -08:00
@@ -249,10 +249,9 @@
 /* Call me when a conntrack is destroyed. */
 extern void (*ip_conntrack_destroyed)(struct ip_conntrack *conntrack);
 
-extern int ip_ct_no_defrag;
 /* Returns new sk_buff, or NULL */
 struct sk_buff *
-ip_ct_gather_frags(struct sk_buff *skb);
+ip_ct_gather_frags(struct sk_buff *skb, u_int32_t user);
 
 /* Delete all conntracks which match. */
 extern void
diff -Nru a/include/net/ip.h b/include/net/ip.h
--- a/include/net/ip.h	2005-02-01 16:04:11 -08:00
+++ b/include/net/ip.h	2005-02-01 16:04:11 -08:00
@@ -227,9 +227,19 @@
 /*
  *	Functions provided by ip_fragment.o
  */
- 
-struct sk_buff *ip_defrag(struct sk_buff *skb);
-extern void ipfrag_flush(void);
+
+enum ip_defrag_users
+{
+	IP_DEFRAG_LOCAL_DELIVER,
+	IP_DEFRAG_CALL_RA_CHAIN,
+	IP_DEFRAG_CONNTRACK_IN,
+	IP_DEFRAG_CONNTRACK_OUT,
+	IP_DEFRAG_NAT_OUT,
+	IP_DEFRAG_VS_OUT,
+	IP_DEFRAG_VS_FWD
+};
+
+struct sk_buff *ip_defrag(struct sk_buff *skb, u32 user);
 extern int ip_frag_nqueues;
 extern atomic_t ip_frag_mem;
 
diff -Nru a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
--- a/net/ipv4/ip_fragment.c	2005-02-01 16:04:11 -08:00
+++ b/net/ipv4/ip_fragment.c	2005-02-01 16:04:11 -08:00
@@ -72,6 +72,7 @@
 struct ipq {
 	struct ipq	*next;		/* linked list pointers			*/
 	struct list_head lru_list;	/* lru list member 			*/
+	u32		user;
 	u32		saddr;
 	u32		daddr;
 	u16		id;
@@ -242,13 +243,13 @@
 /* Memory limiting on fragments.  Evictor trashes the oldest 
  * fragment queue until we are back under the threshold.
  */
-static void __ip_evictor(int threshold)
+static void ip_evictor(void)
 {
 	struct ipq *qp;
 	struct list_head *tmp;
 	int work;
 
-	work = atomic_read(&ip_frag_mem) - threshold;
+	work = atomic_read(&ip_frag_mem) - sysctl_ipfrag_low_thresh;
 	if (work <= 0)
 		return;
 
@@ -273,11 +274,6 @@
 	}
 }
 
-static inline void ip_evictor(void)
-{
-	__ip_evictor(sysctl_ipfrag_low_thresh);
-}
-
 /*
  * Oops, a fragment queue timed out.  Kill it and send an ICMP reply.
  */
@@ -324,7 +320,8 @@
 		if(qp->id == qp_in->id		&&
 		   qp->saddr == qp_in->saddr	&&
 		   qp->daddr == qp_in->daddr	&&
-		   qp->protocol == qp_in->protocol) {
+		   qp->protocol == qp_in->protocol &&
+		   qp->user == qp_in->user) {
 			atomic_inc(&qp->refcnt);
 			write_unlock(&ipfrag_lock);
 			qp_in->last_in |= COMPLETE;
@@ -351,7 +348,7 @@
 }
 
 /* Add an entry to the 'ipq' queue for a newly received IP datagram. */
-static struct ipq *ip_frag_create(unsigned hash, struct iphdr *iph)
+static struct ipq *ip_frag_create(unsigned hash, struct iphdr *iph, u32 user)
 {
 	struct ipq *qp;
 
@@ -363,6 +360,7 @@
 	qp->id = iph->id;
 	qp->saddr = iph->saddr;
 	qp->daddr = iph->daddr;
+	qp->user = user;
 	qp->len = 0;
 	qp->meat = 0;
 	qp->fragments = NULL;
@@ -385,7 +383,7 @@
 /* Find the correct entry in the "incomplete datagrams" queue for
  * this IP datagram, and create new one, if nothing is found.
  */
-static inline struct ipq *ip_find(struct iphdr *iph)
+static inline struct ipq *ip_find(struct iphdr *iph, u32 user)
 {
 	__u16 id = iph->id;
 	__u32 saddr = iph->saddr;
@@ -399,7 +397,8 @@
 		if(qp->id == id		&&
 		   qp->saddr == saddr	&&
 		   qp->daddr == daddr	&&
-		   qp->protocol == protocol) {
+		   qp->protocol == protocol &&
+		   qp->user == user) {
 			atomic_inc(&qp->refcnt);
 			read_unlock(&ipfrag_lock);
 			return qp;
@@ -407,7 +406,7 @@
 	}
 	read_unlock(&ipfrag_lock);
 
-	return ip_frag_create(hash, iph);
+	return ip_frag_create(hash, iph, user);
 }
 
 /* Add new segment to existing queue. */
@@ -641,7 +640,7 @@
 }
 
 /* Process an incoming IP datagram fragment. */
-struct sk_buff *ip_defrag(struct sk_buff *skb)
+struct sk_buff *ip_defrag(struct sk_buff *skb, u32 user)
 {
 	struct iphdr *iph = skb->nh.iph;
 	struct ipq *qp;
@@ -656,7 +655,7 @@
 	dev = skb->dev;
 
 	/* Lookup (or create) queue header */
-	if ((qp = ip_find(iph)) != NULL) {
+	if ((qp = ip_find(iph, user)) != NULL) {
 		struct sk_buff *ret = NULL;
 
 		spin_lock(&qp->lock);
@@ -686,9 +685,4 @@
 	ipfrag_secret_timer.function = ipfrag_secret_rebuild;
 	ipfrag_secret_timer.expires = jiffies + sysctl_ipfrag_secret_interval;
 	add_timer(&ipfrag_secret_timer);
-}
-
-void ipfrag_flush(void)
-{
-	__ip_evictor(0);
 }
diff -Nru a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
--- a/net/ipv4/ip_input.c	2005-02-01 16:04:11 -08:00
+++ b/net/ipv4/ip_input.c	2005-02-01 16:04:11 -08:00
@@ -170,7 +170,7 @@
 		    && ((sk->bound_dev_if == 0) 
 			|| (sk->bound_dev_if == skb->dev->ifindex))) {
 			if (skb->nh.iph->frag_off & htons(IP_MF|IP_OFFSET)) {
-				skb = ip_defrag(skb);
+				skb = ip_defrag(skb, IP_DEFRAG_CALL_RA_CHAIN);
 				if (skb == NULL) {
 					read_unlock(&ip_ra_lock);
 					return 1;
@@ -291,7 +291,7 @@
 	 */
 
 	if (skb->nh.iph->frag_off & htons(IP_MF|IP_OFFSET)) {
-		skb = ip_defrag(skb);
+		skb = ip_defrag(skb, IP_DEFRAG_LOCAL_DELIVER);
 		if (!skb)
 			return 0;
 	}
diff -Nru a/net/ipv4/ipvs/ip_vs_core.c b/net/ipv4/ipvs/ip_vs_core.c
--- a/net/ipv4/ipvs/ip_vs_core.c	2005-02-01 16:04:11 -08:00
+++ b/net/ipv4/ipvs/ip_vs_core.c	2005-02-01 16:04:11 -08:00
@@ -506,7 +506,7 @@
 
 	/* reassemble IP fragments, but will it happen in ICMP packets?? */
 	if (skb->nh.iph->frag_off & __constant_htons(IP_MF|IP_OFFSET)) {
-		skb = ip_defrag(skb);
+		skb = ip_defrag(skb, IP_DEFRAG_VS_OUT);
 		if (!skb)
 			return NF_STOLEN;
 		*skb_p = skb;
@@ -658,7 +658,7 @@
 
 	/* reassemble IP fragments */
 	if (iph->frag_off & __constant_htons(IP_MF|IP_OFFSET)) {
-		skb = ip_defrag(skb);
+		skb = ip_defrag(skb, IP_DEFRAG_VS_OUT);
 		if (!skb)
 			return NF_STOLEN;
 		iph = skb->nh.iph;
@@ -1164,7 +1164,7 @@
 		return NF_ACCEPT;
 
 	if (iph->frag_off & __constant_htons(IP_MF|IP_OFFSET)) {
-		skb = ip_defrag(skb);
+		skb = ip_defrag(skb, IP_DEFRAG_VS_FWD);
 		if (!skb)
 			return NF_STOLEN;
 		*skb_p = skb;
diff -Nru a/net/ipv4/netfilter/ip_conntrack_core.c b/net/ipv4/netfilter/ip_conntrack_core.c
--- a/net/ipv4/netfilter/ip_conntrack_core.c	2005-02-01 16:04:11 -08:00
+++ b/net/ipv4/netfilter/ip_conntrack_core.c	2005-02-01 16:04:11 -08:00
@@ -834,7 +834,10 @@
 
 	/* Gather fragments. */
 	if ((*pskb)->nh.iph->frag_off & htons(IP_MF|IP_OFFSET)) {
-		*pskb = ip_ct_gather_frags(*pskb);
+		*pskb = ip_ct_gather_frags(*pskb,
+		                           hooknum == NF_IP_PRE_ROUTING ?
+		                           IP_DEFRAG_CONNTRACK_IN :
+		                           IP_DEFRAG_CONNTRACK_OUT);
 		if (!*pskb)
 			return NF_STOLEN;
 	}
@@ -1183,29 +1186,22 @@
 	WRITE_UNLOCK(&ip_conntrack_lock);
 }
 
-int ip_ct_no_defrag;
-
 /* Returns new sk_buff, or NULL */
 struct sk_buff *
-ip_ct_gather_frags(struct sk_buff *skb)
+ip_ct_gather_frags(struct sk_buff *skb, u_int32_t user)
 {
 	struct sock *sk = skb->sk;
 #ifdef CONFIG_NETFILTER_DEBUG
 	unsigned int olddebug = skb->nf_debug;
 #endif
 
-	if (unlikely(ip_ct_no_defrag)) {
-		kfree_skb(skb);
-		return NULL;
-	}
-
 	if (sk) {
 		sock_hold(sk);
 		skb_orphan(skb);
 	}
 
 	local_bh_disable(); 
-	skb = ip_defrag(skb);
+	skb = ip_defrag(skb, user);
 	local_bh_enable();
 
 	if (!skb) {
diff -Nru a/net/ipv4/netfilter/ip_conntrack_standalone.c b/net/ipv4/netfilter/ip_conntrack_standalone.c
--- a/net/ipv4/netfilter/ip_conntrack_standalone.c	2005-02-01 16:04:11 -08:00
+++ b/net/ipv4/netfilter/ip_conntrack_standalone.c	2005-02-01 16:04:11 -08:00
@@ -393,13 +393,6 @@
  cleanup_inandlocalops:
 	nf_unregister_hook(&ip_conntrack_local_out_ops);
  cleanup_inops:
-	/* Frag queues may hold fragments with skb->dst == NULL */
-	ip_ct_no_defrag = 1;
-	local_bh_disable();
-	br_write_lock(BR_NETPROTO_LOCK);
-	br_write_unlock(BR_NETPROTO_LOCK);
-	ipfrag_flush();
-	local_bh_enable();
 	nf_unregister_hook(&ip_conntrack_in_ops);
  cleanup_proc:
 	proc_net_remove("ip_conntrack");
diff -Nru a/net/ipv4/netfilter/ip_nat_standalone.c b/net/ipv4/netfilter/ip_nat_standalone.c
--- a/net/ipv4/netfilter/ip_nat_standalone.c	2005-02-01 16:04:11 -08:00
+++ b/net/ipv4/netfilter/ip_nat_standalone.c	2005-02-01 16:04:11 -08:00
@@ -201,7 +201,7 @@
 	   I'm starting to have nightmares about fragments.  */
 
 	if ((*pskb)->nh.iph->frag_off & htons(IP_MF|IP_OFFSET)) {
-		*pskb = ip_ct_gather_frags(*pskb);
+		*pskb = ip_ct_gather_frags(*pskb, IP_DEFRAG_NAT_OUT);
 
 		if (!*pskb)
 			return NF_STOLEN;
diff -Nru a/net/netsyms.c b/net/netsyms.c
--- a/net/netsyms.c	2005-02-01 16:04:11 -08:00
+++ b/net/netsyms.c	2005-02-01 16:04:11 -08:00
@@ -287,7 +287,6 @@
 EXPORT_SYMBOL(inetdev_by_index);
 EXPORT_SYMBOL(in_dev_finish_destroy);
 EXPORT_SYMBOL(ip_defrag);
-EXPORT_SYMBOL(ipfrag_flush);
 
 /* Route manipulation */
 EXPORT_SYMBOL(ip_rt_ioctl);