[NETFILTER]: Associate locally generated ICMP errors with conntrack of original packet

ChangeSet 1.1531, 2004/12/21 17:18:37+01:00, [email protected]

	[NETFILTER]: Associate locally generated ICMP errors with conntrack of original packet
	
	Signed-off-by: Patrick McHardy <[email protected]>



 include/linux/netfilter.h       |    2 ++
 include/net/ip.h                |    3 ++-
 net/core/netfilter.c            |   17 +++++++++++++----
 net/ipv4/icmp.c                 |    6 +++++-
 net/ipv4/ip_output.c            |   14 ++++++++------
 net/ipv4/netfilter/ipt_REJECT.c |   16 ++--------------
 net/ipv4/raw.c                  |    4 ++--
 net/ipv4/udp.c                  |    6 ++++--
 net/netsyms.c                   |    1 +
 9 files changed, 39 insertions(+), 30 deletions(-)


diff -Nru a/include/linux/netfilter.h b/include/linux/netfilter.h
--- a/include/linux/netfilter.h	2005-01-15 07:03:47 -08:00
+++ b/include/linux/netfilter.h	2005-01-15 07:03:47 -08:00
@@ -153,6 +153,7 @@
 extern inline struct arpt_target *
 arpt_find_target_lock(const char *name, int *error, struct semaphore *mutex);
 extern void (*ip_ct_attach)(struct sk_buff *, struct nf_ct_info *);
+extern void nf_ct_attach(struct sk_buff *, struct sk_buff *);
 
 #ifdef CONFIG_NETFILTER_DEBUG
 extern void nf_dump_skb(int pf, struct sk_buff *skb);
@@ -163,6 +164,7 @@
 
 #else /* !CONFIG_NETFILTER */
 #define NF_HOOK(pf, hook, skb, indev, outdev, okfn) (okfn)(skb)
+static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {}
 #endif /*CONFIG_NETFILTER*/
 
 /* From arch/i386/kernel/smp.c:
diff -Nru a/include/net/ip.h b/include/net/ip.h
--- a/include/net/ip.h	2005-01-15 07:03:47 -08:00
+++ b/include/net/ip.h	2005-01-15 07:03:47 -08:00
@@ -102,7 +102,8 @@
 				      int getfrag (const void *,
 						   char *,
 						   unsigned int,
-						   unsigned int),
+						   unsigned int,
+						   struct sk_buff *),
 				      const void *frag,
 				      unsigned length,
 				      struct ipcm_cookie *ipc,
diff -Nru a/net/core/netfilter.c b/net/core/netfilter.c
--- a/net/core/netfilter.c	2005-01-15 07:03:47 -08:00
+++ b/net/core/netfilter.c	2005-01-15 07:03:47 -08:00
@@ -622,11 +622,20 @@
 }
 #endif /*CONFIG_INET*/
 
-/* This does not belong here, but ipt_REJECT needs it if connection
-   tracking in use: without this, connection may not be in hash table,
-   and hence manufactured ICMP or RST packets will not be associated
-   with it. */
+/* This does not belong here, but locally generated errors need it if connection
+   tracking in use: without this, connection may not be in hash table, and hence
+   manufactured ICMP or RST packets will not be associated with it. */
 void (*ip_ct_attach)(struct sk_buff *, struct nf_ct_info *);
+
+void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb)
+{
+	void (*attach)(struct sk_buff *, struct nf_ct_info *);
+
+	if (skb->nfct && (attach = ip_ct_attach) != NULL) {
+		mb(); /* Just to be sure: must be read before executing this */
+		attach(new, skb->nfct);
+	}
+}
 
 void __init netfilter_init(void)
 {
diff -Nru a/net/ipv4/icmp.c b/net/ipv4/icmp.c
--- a/net/ipv4/icmp.c	2005-01-15 07:03:47 -08:00
+++ b/net/ipv4/icmp.c	2005-01-15 07:03:47 -08:00
@@ -281,11 +281,15 @@
  *	Checksum each fragment, and on the first include the headers and final checksum.
  */
  
-static int icmp_glue_bits(const void *p, char *to, unsigned int offset, unsigned int fraglen)
+static int icmp_glue_bits(const void *p, char *to, unsigned int offset,
+                          unsigned int fraglen, struct sk_buff *skb)
 {
 	struct icmp_bxm *icmp_param = (struct icmp_bxm *)p;
 	struct icmphdr *icmph;
 	unsigned int csum;
+
+	if (icmp_pointers[icmp_param->data.icmph.type].error)
+		nf_ct_attach(skb, icmp_param->skb);
 
 	if (offset) {
 		icmp_param->csum=skb_copy_and_csum_bits(icmp_param->skb,
diff -Nru a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
--- a/net/ipv4/ip_output.c	2005-01-15 07:03:47 -08:00
+++ b/net/ipv4/ip_output.c	2005-01-15 07:03:47 -08:00
@@ -438,7 +438,8 @@
 		  int getfrag (const void *,
 			       char *,
 			       unsigned int,	
-			       unsigned int),
+			       unsigned int,
+			       struct sk_buff *),
 		  const void *frag,
 		  unsigned length,
 		  struct ipcm_cookie *ipc,
@@ -607,7 +608,7 @@
 		 *	User data callback
 		 */
 
-		if (getfrag(frag, data, offset, fraglen-fragheaderlen)) {
+		if (getfrag(frag, data, offset, fraglen-fragheaderlen, skb)) {
 			err = -EFAULT;
 			kfree_skb(skb);
 			goto error;
@@ -647,7 +648,8 @@
 		  int getfrag (const void *,
 			       char *,
 			       unsigned int,	
-			       unsigned int),
+			       unsigned int,
+			       struct sk_buff *),
 		  const void *frag,
 		  unsigned length,
 		  struct ipcm_cookie *ipc,
@@ -721,10 +723,10 @@
 		iph->daddr=rt->rt_dst;
 		iph->check=0;
 		iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
-		err = getfrag(frag, ((char *)iph)+iph->ihl*4,0, length-iph->ihl*4);
+		err = getfrag(frag, ((char *)iph)+iph->ihl*4,0, length-iph->ihl*4, skb);
 	}
 	else
-		err = getfrag(frag, (void *)iph, 0, length);
+		err = getfrag(frag, (void *)iph, 0, length, skb);
 
 	if (err)
 		goto error_fault;
@@ -921,7 +923,7 @@
  *	Fetch data from kernel space and fill in checksum if needed.
  */
 static int ip_reply_glue_bits(const void *dptr, char *to, unsigned int offset, 
-			      unsigned int fraglen)
+			      unsigned int fraglen, struct sk_buff *skb)
 {
         struct ip_reply_arg *dp = (struct ip_reply_arg*)dptr;
 	u16 *pktp = (u16 *)to;
diff -Nru a/net/ipv4/netfilter/ipt_REJECT.c b/net/ipv4/netfilter/ipt_REJECT.c
--- a/net/ipv4/netfilter/ipt_REJECT.c	2005-01-15 07:03:47 -08:00
+++ b/net/ipv4/netfilter/ipt_REJECT.c	2005-01-15 07:03:47 -08:00
@@ -22,18 +22,6 @@
 #define DEBUGP(format, args...)
 #endif
 
-/* If the original packet is part of a connection, but the connection
-   is not confirmed, our manufactured reply will not be associated
-   with it, so we need to do this manually. */
-static void connection_attach(struct sk_buff *new_skb, struct nf_ct_info *nfct)
-{
-	void (*attach)(struct sk_buff *, struct nf_ct_info *);
-
-	/* Avoid module unload race with ip_ct_attach being NULLed out */
-	if (nfct && (attach = ip_ct_attach) != NULL)
-		attach(new_skb, nfct);
-}
-
 static inline struct rtable *route_reverse(struct sk_buff *skb, int hook)
 {
 	struct iphdr *iph = skb->nh.iph;
@@ -187,7 +175,7 @@
 	if (nskb->len > nskb->dst->pmtu)
 		goto free_nskb;
 
-	connection_attach(nskb, oldskb->nfct);
+	nf_ct_attach(nskb, oldskb);
 
 	NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, nskb, NULL, nskb->dst->dev,
 		ip_finish_output);
@@ -323,7 +311,7 @@
 	icmph->checksum = ip_compute_csum((unsigned char *)icmph,
 					  length - sizeof(struct iphdr));
 
-	connection_attach(nskb, skb_in->nfct);
+	nf_ct_attach(nskb, skb_in);
 
 	NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, nskb, NULL, nskb->dst->dev,
 		ip_finish_output);
diff -Nru a/net/ipv4/raw.c b/net/ipv4/raw.c
--- a/net/ipv4/raw.c	2005-01-15 07:03:47 -08:00
+++ b/net/ipv4/raw.c	2005-01-15 07:03:47 -08:00
@@ -266,7 +266,7 @@
  */
   
 static int raw_getfrag(const void *p, char *to, unsigned int offset,
-			unsigned int fraglen)
+		       unsigned int fraglen, struct sk_buff *skb)
 {
 	struct rawfakehdr *rfh = (struct rawfakehdr *) p;
 	return memcpy_fromiovecend(to, rfh->iov, offset, fraglen);
@@ -277,7 +277,7 @@
  */
  
 static int raw_getrawfrag(const void *p, char *to, unsigned int offset,
-				unsigned int fraglen)
+				unsigned int fraglen, struct sk_buff *skb)
 {
 	struct rawfakehdr *rfh = (struct rawfakehdr *) p;
 
diff -Nru a/net/ipv4/udp.c b/net/ipv4/udp.c
--- a/net/ipv4/udp.c	2005-01-15 07:03:47 -08:00
+++ b/net/ipv4/udp.c	2005-01-15 07:03:47 -08:00
@@ -389,7 +389,8 @@
  *	Copy and checksum a UDP packet from user space into a buffer.
  */
  
-static int udp_getfrag(const void *p, char * to, unsigned int offset, unsigned int fraglen) 
+static int udp_getfrag(const void *p, char * to, unsigned int offset,
+                       unsigned int fraglen, struct sk_buff *skb)
 {
 	struct udpfakehdr *ufh = (struct udpfakehdr *)p;
 	if (offset==0) {
@@ -416,7 +417,8 @@
  *	Copy a UDP packet from user space into a buffer without checksumming.
  */
  
-static int udp_getfrag_nosum(const void *p, char * to, unsigned int offset, unsigned int fraglen) 
+static int udp_getfrag_nosum(const void *p, char * to, unsigned int offset,
+                             unsigned int fraglen, struct sk_buff *skb) 
 {
 	struct udpfakehdr *ufh = (struct udpfakehdr *)p;
 
diff -Nru a/net/netsyms.c b/net/netsyms.c
--- a/net/netsyms.c	2005-01-15 07:03:47 -08:00
+++ b/net/netsyms.c	2005-01-15 07:03:47 -08:00
@@ -607,6 +607,7 @@
 EXPORT_SYMBOL(nf_setsockopt);
 EXPORT_SYMBOL(nf_getsockopt);
 EXPORT_SYMBOL(ip_ct_attach);
+EXPORT_SYMBOL(nf_ct_attach);
 #ifdef CONFIG_INET
 #include <linux/netfilter_ipv4.h>
 EXPORT_SYMBOL(ip_route_me_harder);