diff options
Diffstat (limited to 'net/ipv4/ip_fragment.c')
-rw-r--r-- | net/ipv4/ip_fragment.c | 159 |
1 files changed, 51 insertions, 108 deletions
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index 443b3f89192f..2143bf30597a 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -108,6 +108,11 @@ int ip_frag_mem(void) static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, struct net_device *dev); +struct ip4_create_arg { + struct iphdr *iph; + u32 user; +}; + static unsigned int ipqhashfn(__be16 id, __be32 saddr, __be32 daddr, u8 prot) { return jhash_3words((__force u32)id << 16 | prot, @@ -123,6 +128,19 @@ static unsigned int ip4_hashfn(struct inet_frag_queue *q) return ipqhashfn(ipq->id, ipq->saddr, ipq->daddr, ipq->protocol); } +static int ip4_frag_match(struct inet_frag_queue *q, void *a) +{ + struct ipq *qp; + struct ip4_create_arg *arg = a; + + qp = container_of(q, struct ipq, q); + return (qp->id == arg->iph->id && + qp->saddr == arg->iph->saddr && + qp->daddr == arg->iph->daddr && + qp->protocol == arg->iph->protocol && + qp->user == arg->user); +} + /* Memory Tracking Functions. */ static __inline__ void frag_kfree_skb(struct sk_buff *skb, int *work) { @@ -132,6 +150,20 @@ static __inline__ void frag_kfree_skb(struct sk_buff *skb, int *work) kfree_skb(skb); } +static void ip4_frag_init(struct inet_frag_queue *q, void *a) +{ + struct ipq *qp = container_of(q, struct ipq, q); + struct ip4_create_arg *arg = a; + + qp->protocol = arg->iph->protocol; + qp->id = arg->iph->id; + qp->saddr = arg->iph->saddr; + qp->daddr = arg->iph->daddr; + qp->user = arg->user; + qp->peer = sysctl_ipfrag_max_dist ? + inet_getpeer(arg->iph->saddr, 1) : NULL; +} + static __inline__ void ip4_frag_free(struct inet_frag_queue *q) { struct ipq *qp; @@ -139,17 +171,6 @@ static __inline__ void ip4_frag_free(struct inet_frag_queue *q) qp = container_of(q, struct ipq, q); if (qp->peer) inet_putpeer(qp->peer); - kfree(qp); -} - -static __inline__ struct ipq *frag_alloc_queue(void) -{ - struct ipq *qp = kzalloc(sizeof(struct ipq), GFP_ATOMIC); - - if (!qp) - return NULL; - atomic_add(sizeof(struct ipq), &ip4_frags.mem); - return qp; } @@ -185,7 +206,9 @@ static void ip_evictor(void) */ static void ip_expire(unsigned long arg) { - struct ipq *qp = (struct ipq *) arg; + struct ipq *qp; + + qp = container_of((struct inet_frag_queue *) arg, struct ipq, q); spin_lock(&qp->q.lock); @@ -210,112 +233,30 @@ out: ipq_put(qp); } -/* Creation primitives. */ - -static struct ipq *ip_frag_intern(struct ipq *qp_in) +/* 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, u32 user) { - struct ipq *qp; -#ifdef CONFIG_SMP - struct hlist_node *n; -#endif + struct inet_frag_queue *q; + struct ip4_create_arg arg; unsigned int hash; - write_lock(&ip4_frags.lock); - hash = ipqhashfn(qp_in->id, qp_in->saddr, qp_in->daddr, - qp_in->protocol); -#ifdef CONFIG_SMP - /* With SMP race we have to recheck hash table, because - * such entry could be created on other cpu, while we - * promoted read lock to write lock. - */ - hlist_for_each_entry(qp, n, &ip4_frags.hash[hash], q.list) { - if (qp->id == qp_in->id && - qp->saddr == qp_in->saddr && - qp->daddr == qp_in->daddr && - qp->protocol == qp_in->protocol && - qp->user == qp_in->user) { - atomic_inc(&qp->q.refcnt); - write_unlock(&ip4_frags.lock); - qp_in->q.last_in |= COMPLETE; - ipq_put(qp_in); - return qp; - } - } -#endif - qp = qp_in; - - if (!mod_timer(&qp->q.timer, jiffies + ip4_frags_ctl.timeout)) - atomic_inc(&qp->q.refcnt); + arg.iph = iph; + arg.user = user; + hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol); - atomic_inc(&qp->q.refcnt); - hlist_add_head(&qp->q.list, &ip4_frags.hash[hash]); - INIT_LIST_HEAD(&qp->q.lru_list); - list_add_tail(&qp->q.lru_list, &ip4_frags.lru_list); - ip4_frags.nqueues++; - write_unlock(&ip4_frags.lock); - return qp; -} - -/* Add an entry to the 'ipq' queue for a newly received IP datagram. */ -static struct ipq *ip_frag_create(struct iphdr *iph, u32 user) -{ - struct ipq *qp; - - if ((qp = frag_alloc_queue()) == NULL) + q = inet_frag_find(&ip4_frags, &arg, hash); + if (q == NULL) goto out_nomem; - qp->protocol = iph->protocol; - qp->id = iph->id; - qp->saddr = iph->saddr; - qp->daddr = iph->daddr; - qp->user = user; - qp->peer = sysctl_ipfrag_max_dist ? inet_getpeer(iph->saddr, 1) : NULL; - - /* Initialize a timer for this entry. */ - init_timer(&qp->q.timer); - qp->q.timer.data = (unsigned long) qp; /* pointer to queue */ - qp->q.timer.function = ip_expire; /* expire function */ - spin_lock_init(&qp->q.lock); - atomic_set(&qp->q.refcnt, 1); - - return ip_frag_intern(qp); + return container_of(q, struct ipq, q); out_nomem: LIMIT_NETDEBUG(KERN_ERR "ip_frag_create: no memory left !\n"); return NULL; } -/* 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, u32 user) -{ - __be16 id = iph->id; - __be32 saddr = iph->saddr; - __be32 daddr = iph->daddr; - __u8 protocol = iph->protocol; - unsigned int hash; - struct ipq *qp; - struct hlist_node *n; - - read_lock(&ip4_frags.lock); - hash = ipqhashfn(id, saddr, daddr, protocol); - hlist_for_each_entry(qp, n, &ip4_frags.hash[hash], q.list) { - if (qp->id == id && - qp->saddr == saddr && - qp->daddr == daddr && - qp->protocol == protocol && - qp->user == user) { - atomic_inc(&qp->q.refcnt); - read_unlock(&ip4_frags.lock); - return qp; - } - } - read_unlock(&ip4_frags.lock); - - return ip_frag_create(iph, user); -} - /* Is the fragment too far ahead to be part of ipq? */ static inline int ip_frag_too_far(struct ipq *qp) { @@ -545,7 +486,6 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, if (prev) { head = prev->next; fp = skb_clone(head, GFP_ATOMIC); - if (!fp) goto out_nomem; @@ -571,7 +511,6 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, goto out_oversize; /* Head of list must not be cloned. */ - err = -ENOMEM; if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) goto out_nomem; @@ -627,6 +566,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, out_nomem: LIMIT_NETDEBUG(KERN_ERR "IP: queue_glue: no memory for gluing " "queue %p\n", qp); + err = -ENOMEM; goto out_fail; out_oversize: if (net_ratelimit()) @@ -671,9 +611,12 @@ void __init ipfrag_init(void) { ip4_frags.ctl = &ip4_frags_ctl; ip4_frags.hashfn = ip4_hashfn; + ip4_frags.constructor = ip4_frag_init; ip4_frags.destructor = ip4_frag_free; ip4_frags.skb_free = NULL; ip4_frags.qsize = sizeof(struct ipq); + ip4_frags.match = ip4_frag_match; + ip4_frags.frag_expire = ip_expire; inet_frags_init(&ip4_frags); } |