fedora core 6 1.2949 + vserver 2.2.0
[linux-2.6.git] / net / ipv6 / reassembly.c
index 15e1456..6f9a904 100644 (file)
@@ -28,7 +28,6 @@
  *     YOSHIFUJI,H. @USAGI     Always remove fragment header to
  *                             calculate ICV correctly.
  */
-#include <linux/config.h>
 #include <linux/errno.h>
 #include <linux/types.h>
 #include <linux/string.h>
 #include <net/snmp.h>
 
 #include <net/ipv6.h>
+#include <net/ip6_route.h>
 #include <net/protocol.h>
 #include <net/transp_v6.h>
 #include <net/rawv6.h>
 #include <net/ndisc.h>
 #include <net/addrconf.h>
 
-int sysctl_ip6frag_high_thresh = 256*1024;
-int sysctl_ip6frag_low_thresh = 192*1024;
+int sysctl_ip6frag_high_thresh __read_mostly = 256*1024;
+int sysctl_ip6frag_low_thresh __read_mostly = 192*1024;
 
-int sysctl_ip6frag_time = IPV6_FRAG_TIMEOUT;
+int sysctl_ip6frag_time __read_mostly = IPV6_FRAG_TIMEOUT;
 
 struct ip6frag_skb_cb
 {
@@ -77,7 +77,7 @@ struct frag_queue
        struct hlist_node       list;
        struct list_head lru_list;              /* lru list member      */
 
-       __u32                   id;             /* fragment id          */
+       __be32                  id;             /* fragment id          */
        struct in6_addr         saddr;
        struct in6_addr         daddr;
 
@@ -121,35 +121,39 @@ static __inline__ void fq_unlink(struct frag_queue *fq)
        write_unlock(&ip6_frag_lock);
 }
 
-static unsigned int ip6qhashfn(u32 id, struct in6_addr *saddr,
+/*
+ * callers should be careful not to use the hash value outside the ipfrag_lock
+ * as doing so could race with ipfrag_hash_rnd being recalculated.
+ */
+static unsigned int ip6qhashfn(__be32 id, struct in6_addr *saddr,
                               struct in6_addr *daddr)
 {
        u32 a, b, c;
 
-       a = saddr->s6_addr32[0];
-       b = saddr->s6_addr32[1];
-       c = saddr->s6_addr32[2];
+       a = (__force u32)saddr->s6_addr32[0];
+       b = (__force u32)saddr->s6_addr32[1];
+       c = (__force u32)saddr->s6_addr32[2];
 
        a += JHASH_GOLDEN_RATIO;
        b += JHASH_GOLDEN_RATIO;
        c += ip6_frag_hash_rnd;
        __jhash_mix(a, b, c);
 
-       a += saddr->s6_addr32[3];
-       b += daddr->s6_addr32[0];
-       c += daddr->s6_addr32[1];
+       a += (__force u32)saddr->s6_addr32[3];
+       b += (__force u32)daddr->s6_addr32[0];
+       c += (__force u32)daddr->s6_addr32[1];
        __jhash_mix(a, b, c);
 
-       a += daddr->s6_addr32[2];
-       b += daddr->s6_addr32[3];
-       c += id;
+       a += (__force u32)daddr->s6_addr32[2];
+       b += (__force u32)daddr->s6_addr32[3];
+       c += (__force u32)id;
        __jhash_mix(a, b, c);
 
        return c & (IP6Q_HASHSZ - 1);
 }
 
 static struct timer_list ip6_frag_secret_timer;
-int sysctl_ip6frag_secret_interval = 10 * 60 * HZ;
+int sysctl_ip6frag_secret_interval __read_mostly = 10 * 60 * HZ;
 
 static void ip6_frag_secret_rebuild(unsigned long dummy)
 {
@@ -203,7 +207,7 @@ static inline void frag_free_queue(struct frag_queue *fq, int *work)
 
 static inline struct frag_queue *frag_alloc_queue(void)
 {
-       struct frag_queue *fq = kmalloc(sizeof(struct frag_queue), GFP_ATOMIC);
+       struct frag_queue *fq = kzalloc(sizeof(struct frag_queue), GFP_ATOMIC);
 
        if(!fq)
                return NULL;
@@ -254,7 +258,7 @@ static __inline__ void fq_kill(struct frag_queue *fq)
        }
 }
 
-static void ip6_evictor(void)
+static void ip6_evictor(struct inet6_dev *idev)
 {
        struct frag_queue *fq;
        struct list_head *tmp;
@@ -281,13 +285,14 @@ static void ip6_evictor(void)
                spin_unlock(&fq->lock);
 
                fq_put(fq, &work);
-               IP6_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
+               IP6_INC_STATS_BH(idev, IPSTATS_MIB_REASMFAILS);
        }
 }
 
 static void ip6_frag_expire(unsigned long data)
 {
        struct frag_queue *fq = (struct frag_queue *) data;
+       struct net_device *dev = NULL;
 
        spin_lock(&fq->lock);
 
@@ -296,26 +301,29 @@ static void ip6_frag_expire(unsigned long data)
 
        fq_kill(fq);
 
-       IP6_INC_STATS_BH(IPSTATS_MIB_REASMTIMEOUT);
-       IP6_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
+       dev = dev_get_by_index(fq->iif);
+       if (!dev)
+               goto out;
 
-       /* Send error only if the first segment arrived. */
-       if (fq->last_in&FIRST_IN && fq->fragments) {
-               struct net_device *dev = dev_get_by_index(fq->iif);
+       rcu_read_lock();
+       IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT);
+       IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMFAILS);
+       rcu_read_unlock();
 
-               /*
-                  But use as source device on which LAST ARRIVED
-                  segment was received. And do not use fq->dev
-                  pointer directly, device might already disappeared.
-                */
-               if (dev) {
-                       fq->fragments->dev = dev;
-                       icmpv6_send(fq->fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0,
-                                   dev);
-                       dev_put(dev);
-               }
-       }
+       /* Don't send error if the first segment did not arrive. */
+       if (!(fq->last_in&FIRST_IN) || !fq->fragments)
+               goto out;
+
+       /*
+          But use as source device on which LAST ARRIVED
+          segment was received. And do not use fq->dev
+          pointer directly, device might already disappeared.
+        */
+       fq->fragments->dev = dev;
+       icmpv6_send(fq->fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0, dev);
 out:
+       if (dev)
+               dev_put(dev);
        spin_unlock(&fq->lock);
        fq_put(fq, NULL);
 }
@@ -323,15 +331,16 @@ out:
 /* Creation primitives. */
 
 
-static struct frag_queue *ip6_frag_intern(unsigned int hash,
-                                         struct frag_queue *fq_in)
+static struct frag_queue *ip6_frag_intern(struct frag_queue *fq_in)
 {
        struct frag_queue *fq;
+       unsigned int hash;
 #ifdef CONFIG_SMP
        struct hlist_node *n;
 #endif
 
        write_lock(&ip6_frag_lock);
+       hash = ip6qhashfn(fq_in->id, &fq_in->saddr, &fq_in->daddr);
 #ifdef CONFIG_SMP
        hlist_for_each_entry(fq, n, &ip6_frag_hash[hash], list) {
                if (fq->id == fq_in->id && 
@@ -361,15 +370,14 @@ static struct frag_queue *ip6_frag_intern(unsigned int hash,
 
 
 static struct frag_queue *
-ip6_frag_create(unsigned int hash, u32 id, struct in6_addr *src, struct in6_addr *dst)
+ip6_frag_create(__be32 id, struct in6_addr *src, struct in6_addr *dst,
+               struct inet6_dev *idev)
 {
        struct frag_queue *fq;
 
        if ((fq = frag_alloc_queue()) == NULL)
                goto oom;
 
-       memset(fq, 0, sizeof(struct frag_queue));
-
        fq->id = id;
        ipv6_addr_copy(&fq->saddr, src);
        ipv6_addr_copy(&fq->daddr, dst);
@@ -380,21 +388,23 @@ ip6_frag_create(unsigned int hash, u32 id, struct in6_addr *src, struct in6_addr
        spin_lock_init(&fq->lock);
        atomic_set(&fq->refcnt, 1);
 
-       return ip6_frag_intern(hash, fq);
+       return ip6_frag_intern(fq);
 
 oom:
-       IP6_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
+       IP6_INC_STATS_BH(idev, IPSTATS_MIB_REASMFAILS);
        return NULL;
 }
 
 static __inline__ struct frag_queue *
-fq_find(u32 id, struct in6_addr *src, struct in6_addr *dst)
+fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst,
+       struct inet6_dev *idev)
 {
        struct frag_queue *fq;
        struct hlist_node *n;
-       unsigned int hash = ip6qhashfn(id, src, dst);
+       unsigned int hash;
 
        read_lock(&ip6_frag_lock);
+       hash = ip6qhashfn(id, src, dst);
        hlist_for_each_entry(fq, n, &ip6_frag_hash[hash], list) {
                if (fq->id == id && 
                    ipv6_addr_equal(src, &fq->saddr) &&
@@ -406,7 +416,7 @@ fq_find(u32 id, struct in6_addr *src, struct in6_addr *dst)
        }
        read_unlock(&ip6_frag_lock);
 
-       return ip6_frag_create(hash, id, src, dst);
+       return ip6_frag_create(id, src, dst, idev);
 }
 
 
@@ -424,12 +434,13 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
                        ((u8 *) (fhdr + 1) - (u8 *) (skb->nh.ipv6h + 1)));
 
        if ((unsigned int)end > IPV6_MAXPLEN) {
-               IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
+               IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
+                                IPSTATS_MIB_INHDRERRORS);
                icmpv6_param_prob(skb,ICMPV6_HDR_FIELD, (u8*)&fhdr->frag_off - skb->nh.raw);
                return;
        }
 
-       if (skb->ip_summed == CHECKSUM_HW)
+       if (skb->ip_summed == CHECKSUM_COMPLETE)
                skb->csum = csum_sub(skb->csum,
                                     csum_partial(skb->nh.raw, (u8*)(fhdr+1)-skb->nh.raw, 0));
 
@@ -451,7 +462,8 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
                        /* RFC2460 says always send parameter problem in
                         * this case. -DaveM
                         */
-                       IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
+                       IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
+                                        IPSTATS_MIB_INHDRERRORS);
                        icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, 
                                          offsetof(struct ipv6hdr, payload_len));
                        return;
@@ -567,7 +579,7 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
        return;
 
 err:
-       IP6_INC_STATS(IPSTATS_MIB_REASMFAILS);
+       IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMFAILS);
        kfree_skb(skb);
 }
 
@@ -643,7 +655,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in,
                head->len += fp->len;
                if (head->ip_summed != fp->ip_summed)
                        head->ip_summed = CHECKSUM_NONE;
-               else if (head->ip_summed == CHECKSUM_HW)
+               else if (head->ip_summed == CHECKSUM_COMPLETE)
                        head->csum = csum_add(head->csum, fp->csum);
                head->truesize += fp->truesize;
                atomic_sub(fp->truesize, &ip6_frag_mem);
@@ -658,10 +670,12 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in,
        *skb_in = head;
 
        /* Yes, and fold redundant checksum back. 8) */
-       if (head->ip_summed == CHECKSUM_HW)
+       if (head->ip_summed == CHECKSUM_COMPLETE)
                head->csum = csum_partial(head->nh.raw, head->h.raw-head->nh.raw, head->csum);
 
-       IP6_INC_STATS_BH(IPSTATS_MIB_REASMOKS);
+       rcu_read_lock();
+       IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMOKS);
+       rcu_read_unlock();
        fq->fragments = NULL;
        return 1;
 
@@ -673,7 +687,9 @@ out_oom:
        if (net_ratelimit())
                printk(KERN_DEBUG "ip6_frag_reasm: no memory for reassembly\n");
 out_fail:
-       IP6_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
+       rcu_read_lock();
+       IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMFAILS);
+       rcu_read_unlock();
        return -1;
 }
 
@@ -687,16 +703,16 @@ static int ipv6_frag_rcv(struct sk_buff **skbp)
 
        hdr = skb->nh.ipv6h;
 
-       IP6_INC_STATS_BH(IPSTATS_MIB_REASMREQDS);
+       IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMREQDS);
 
        /* Jumbo payload inhibits frag. header */
        if (hdr->payload_len==0) {
-               IP6_INC_STATS(IPSTATS_MIB_INHDRERRORS);
+               IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
                icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb->h.raw-skb->nh.raw);
                return -1;
        }
        if (!pskb_may_pull(skb, (skb->h.raw-skb->data)+sizeof(struct frag_hdr))) {
-               IP6_INC_STATS(IPSTATS_MIB_INHDRERRORS);
+               IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
                icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb->h.raw-skb->nh.raw);
                return -1;
        }
@@ -707,16 +723,17 @@ static int ipv6_frag_rcv(struct sk_buff **skbp)
        if (!(fhdr->frag_off & htons(0xFFF9))) {
                /* It is not a fragmented frame */
                skb->h.raw += sizeof(struct frag_hdr);
-               IP6_INC_STATS_BH(IPSTATS_MIB_REASMOKS);
+               IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMOKS);
 
                IP6CB(skb)->nhoff = (u8*)fhdr - skb->nh.raw;
                return 1;
        }
 
        if (atomic_read(&ip6_frag_mem) > sysctl_ip6frag_high_thresh)
-               ip6_evictor();
+               ip6_evictor(ip6_dst_idev(skb->dst));
 
-       if ((fq = fq_find(fhdr->identification, &hdr->saddr, &hdr->daddr)) != NULL) {
+       if ((fq = fq_find(fhdr->identification, &hdr->saddr, &hdr->daddr,
+                         ip6_dst_idev(skb->dst))) != NULL) {
                int ret = -1;
 
                spin_lock(&fq->lock);
@@ -732,7 +749,7 @@ static int ipv6_frag_rcv(struct sk_buff **skbp)
                return ret;
        }
 
-       IP6_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
+       IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMFAILS);
        kfree_skb(skb);
        return -1;
 }