11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * INET An implementation of the TCP/IP protocol suite for the LINUX 31da177e4SLinus Torvalds * operating system. INET is implemented using the BSD Socket 41da177e4SLinus Torvalds * interface as the means of communication with the user level. 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * The IP fragmentation functionality. 71da177e4SLinus Torvalds * 81da177e4SLinus Torvalds * Authors: Fred N. van Kempen <waltje@uWalt.NL.Mugnet.ORG> 9113aa838SAlan Cox * Alan Cox <alan@lxorguk.ukuu.org.uk> 101da177e4SLinus Torvalds * 111da177e4SLinus Torvalds * Fixes: 121da177e4SLinus Torvalds * Alan Cox : Split from ip.c , see ip_input.c for history. 131da177e4SLinus Torvalds * David S. Miller : Begin massive cleanup... 141da177e4SLinus Torvalds * Andi Kleen : Add sysctls. 151da177e4SLinus Torvalds * xxxx : Overlapfrag bug. 161da177e4SLinus Torvalds * Ultima : ip_expire() kernel panic. 171da177e4SLinus Torvalds * Bill Hawes : Frag accounting and evictor fixes. 181da177e4SLinus Torvalds * John McDonald : 0 length frag bug. 191da177e4SLinus Torvalds * Alexey Kuznetsov: SMP races, threading, cleanup. 201da177e4SLinus Torvalds * Patrick McHardy : LRU queue of frag heads for evictor. 211da177e4SLinus Torvalds */ 221da177e4SLinus Torvalds 2389cee8b1SHerbert Xu #include <linux/compiler.h> 241da177e4SLinus Torvalds #include <linux/module.h> 251da177e4SLinus Torvalds #include <linux/types.h> 261da177e4SLinus Torvalds #include <linux/mm.h> 271da177e4SLinus Torvalds #include <linux/jiffies.h> 281da177e4SLinus Torvalds #include <linux/skbuff.h> 291da177e4SLinus Torvalds #include <linux/list.h> 301da177e4SLinus Torvalds #include <linux/ip.h> 311da177e4SLinus Torvalds #include <linux/icmp.h> 321da177e4SLinus Torvalds #include <linux/netdevice.h> 331da177e4SLinus Torvalds #include <linux/jhash.h> 341da177e4SLinus Torvalds #include <linux/random.h> 351da177e4SLinus Torvalds #include <net/sock.h> 361da177e4SLinus Torvalds #include <net/ip.h> 371da177e4SLinus Torvalds #include <net/icmp.h> 381da177e4SLinus Torvalds #include <net/checksum.h> 3989cee8b1SHerbert Xu #include <net/inetpeer.h> 405ab11c98SPavel Emelyanov #include <net/inet_frag.h> 411da177e4SLinus Torvalds #include <linux/tcp.h> 421da177e4SLinus Torvalds #include <linux/udp.h> 431da177e4SLinus Torvalds #include <linux/inet.h> 441da177e4SLinus Torvalds #include <linux/netfilter_ipv4.h> 451da177e4SLinus Torvalds 461da177e4SLinus Torvalds /* NOTE. Logic of IP defragmentation is parallel to corresponding IPv6 471da177e4SLinus Torvalds * code now. If you change something here, _PLEASE_ update ipv6/reassembly.c 481da177e4SLinus Torvalds * as well. Or notify me, at least. --ANK 491da177e4SLinus Torvalds */ 501da177e4SLinus Torvalds 518d8354d2SPavel Emelyanov static int sysctl_ipfrag_max_dist __read_mostly = 64; 5289cee8b1SHerbert Xu 531da177e4SLinus Torvalds struct ipfrag_skb_cb 541da177e4SLinus Torvalds { 551da177e4SLinus Torvalds struct inet_skb_parm h; 561da177e4SLinus Torvalds int offset; 571da177e4SLinus Torvalds }; 581da177e4SLinus Torvalds 591da177e4SLinus Torvalds #define FRAG_CB(skb) ((struct ipfrag_skb_cb *)((skb)->cb)) 601da177e4SLinus Torvalds 611da177e4SLinus Torvalds /* Describe an entry in the "incomplete datagrams" queue. */ 621da177e4SLinus Torvalds struct ipq { 635ab11c98SPavel Emelyanov struct inet_frag_queue q; 645ab11c98SPavel Emelyanov 651da177e4SLinus Torvalds u32 user; 6618277770SAl Viro __be32 saddr; 6718277770SAl Viro __be32 daddr; 6818277770SAl Viro __be16 id; 691da177e4SLinus Torvalds u8 protocol; 7089cee8b1SHerbert Xu int iif; 7189cee8b1SHerbert Xu unsigned int rid; 7289cee8b1SHerbert Xu struct inet_peer *peer; 731da177e4SLinus Torvalds }; 741da177e4SLinus Torvalds 757eb95156SPavel Emelyanov static struct inet_frags ip4_frags; 761da177e4SLinus Torvalds 77e5a2bb84SPavel Emelyanov int ip_frag_nqueues(struct net *net) 787eb95156SPavel Emelyanov { 79e5a2bb84SPavel Emelyanov return net->ipv4.frags.nqueues; 807eb95156SPavel Emelyanov } 811da177e4SLinus Torvalds 826ddc0822SPavel Emelyanov int ip_frag_mem(struct net *net) 837eb95156SPavel Emelyanov { 846ddc0822SPavel Emelyanov return atomic_read(&net->ipv4.frags.mem); 857eb95156SPavel Emelyanov } 861da177e4SLinus Torvalds 871706d587SHerbert Xu static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, 881706d587SHerbert Xu struct net_device *dev); 891706d587SHerbert Xu 90c6fda282SPavel Emelyanov struct ip4_create_arg { 91c6fda282SPavel Emelyanov struct iphdr *iph; 92c6fda282SPavel Emelyanov u32 user; 93c6fda282SPavel Emelyanov }; 94c6fda282SPavel Emelyanov 9518277770SAl Viro static unsigned int ipqhashfn(__be16 id, __be32 saddr, __be32 daddr, u8 prot) 961da177e4SLinus Torvalds { 9718277770SAl Viro return jhash_3words((__force u32)id << 16 | prot, 9818277770SAl Viro (__force u32)saddr, (__force u32)daddr, 997eb95156SPavel Emelyanov ip4_frags.rnd) & (INETFRAGS_HASHSZ - 1); 1001da177e4SLinus Torvalds } 1011da177e4SLinus Torvalds 102321a3a99SPavel Emelyanov static unsigned int ip4_hashfn(struct inet_frag_queue *q) 1031da177e4SLinus Torvalds { 104321a3a99SPavel Emelyanov struct ipq *ipq; 1051da177e4SLinus Torvalds 106321a3a99SPavel Emelyanov ipq = container_of(q, struct ipq, q); 107321a3a99SPavel Emelyanov return ipqhashfn(ipq->id, ipq->saddr, ipq->daddr, ipq->protocol); 1081da177e4SLinus Torvalds } 1091da177e4SLinus Torvalds 110abd6523dSPavel Emelyanov static int ip4_frag_match(struct inet_frag_queue *q, void *a) 111abd6523dSPavel Emelyanov { 112abd6523dSPavel Emelyanov struct ipq *qp; 113abd6523dSPavel Emelyanov struct ip4_create_arg *arg = a; 114abd6523dSPavel Emelyanov 115abd6523dSPavel Emelyanov qp = container_of(q, struct ipq, q); 116abd6523dSPavel Emelyanov return (qp->id == arg->iph->id && 117abd6523dSPavel Emelyanov qp->saddr == arg->iph->saddr && 118abd6523dSPavel Emelyanov qp->daddr == arg->iph->daddr && 119abd6523dSPavel Emelyanov qp->protocol == arg->iph->protocol && 120abd6523dSPavel Emelyanov qp->user == arg->user); 121abd6523dSPavel Emelyanov } 122abd6523dSPavel Emelyanov 1231da177e4SLinus Torvalds /* Memory Tracking Functions. */ 1246ddc0822SPavel Emelyanov static __inline__ void frag_kfree_skb(struct netns_frags *nf, 1256ddc0822SPavel Emelyanov struct sk_buff *skb, int *work) 1261da177e4SLinus Torvalds { 1271da177e4SLinus Torvalds if (work) 1281da177e4SLinus Torvalds *work -= skb->truesize; 1296ddc0822SPavel Emelyanov atomic_sub(skb->truesize, &nf->mem); 1301da177e4SLinus Torvalds kfree_skb(skb); 1311da177e4SLinus Torvalds } 1321da177e4SLinus Torvalds 133c6fda282SPavel Emelyanov static void ip4_frag_init(struct inet_frag_queue *q, void *a) 134c6fda282SPavel Emelyanov { 135c6fda282SPavel Emelyanov struct ipq *qp = container_of(q, struct ipq, q); 136c6fda282SPavel Emelyanov struct ip4_create_arg *arg = a; 137c6fda282SPavel Emelyanov 138c6fda282SPavel Emelyanov qp->protocol = arg->iph->protocol; 139c6fda282SPavel Emelyanov qp->id = arg->iph->id; 140c6fda282SPavel Emelyanov qp->saddr = arg->iph->saddr; 141c6fda282SPavel Emelyanov qp->daddr = arg->iph->daddr; 142c6fda282SPavel Emelyanov qp->user = arg->user; 143c6fda282SPavel Emelyanov qp->peer = sysctl_ipfrag_max_dist ? 144c6fda282SPavel Emelyanov inet_getpeer(arg->iph->saddr, 1) : NULL; 145c6fda282SPavel Emelyanov } 146c6fda282SPavel Emelyanov 1471e4b8287SPavel Emelyanov static __inline__ void ip4_frag_free(struct inet_frag_queue *q) 1481da177e4SLinus Torvalds { 1491e4b8287SPavel Emelyanov struct ipq *qp; 1501e4b8287SPavel Emelyanov 1511e4b8287SPavel Emelyanov qp = container_of(q, struct ipq, q); 1521e4b8287SPavel Emelyanov if (qp->peer) 1531e4b8287SPavel Emelyanov inet_putpeer(qp->peer); 1541da177e4SLinus Torvalds } 1551da177e4SLinus Torvalds 1561da177e4SLinus Torvalds 1571da177e4SLinus Torvalds /* Destruction primitives. */ 1581da177e4SLinus Torvalds 1594b6cb5d8SPavel Emelyanov static __inline__ void ipq_put(struct ipq *ipq) 1601da177e4SLinus Torvalds { 161762cc408SPavel Emelyanov inet_frag_put(&ipq->q, &ip4_frags); 1621da177e4SLinus Torvalds } 1631da177e4SLinus Torvalds 1641da177e4SLinus Torvalds /* Kill ipq entry. It is not destroyed immediately, 1651da177e4SLinus Torvalds * because caller (and someone more) holds reference count. 1661da177e4SLinus Torvalds */ 1671da177e4SLinus Torvalds static void ipq_kill(struct ipq *ipq) 1681da177e4SLinus Torvalds { 169277e650dSPavel Emelyanov inet_frag_kill(&ipq->q, &ip4_frags); 1701da177e4SLinus Torvalds } 1711da177e4SLinus Torvalds 1721da177e4SLinus Torvalds /* Memory limiting on fragments. Evictor trashes the oldest 1731da177e4SLinus Torvalds * fragment queue until we are back under the threshold. 1741da177e4SLinus Torvalds */ 1756ddc0822SPavel Emelyanov static void ip_evictor(struct net *net) 1761da177e4SLinus Torvalds { 1778e7999c4SPavel Emelyanov int evicted; 1781da177e4SLinus Torvalds 1796ddc0822SPavel Emelyanov evicted = inet_frag_evictor(&net->ipv4.frags, &ip4_frags); 1808e7999c4SPavel Emelyanov if (evicted) 181c5346fe3SPavel Emelyanov IP_ADD_STATS_BH(net, IPSTATS_MIB_REASMFAILS, evicted); 1821da177e4SLinus Torvalds } 1831da177e4SLinus Torvalds 1841da177e4SLinus Torvalds /* 1851da177e4SLinus Torvalds * Oops, a fragment queue timed out. Kill it and send an ICMP reply. 1861da177e4SLinus Torvalds */ 1871da177e4SLinus Torvalds static void ip_expire(unsigned long arg) 1881da177e4SLinus Torvalds { 189e521db9dSPavel Emelyanov struct ipq *qp; 19084a3aa00SPavel Emelyanov struct net *net; 191e521db9dSPavel Emelyanov 192e521db9dSPavel Emelyanov qp = container_of((struct inet_frag_queue *) arg, struct ipq, q); 19384a3aa00SPavel Emelyanov net = container_of(qp->q.net, struct net, ipv4.frags); 1941da177e4SLinus Torvalds 1955ab11c98SPavel Emelyanov spin_lock(&qp->q.lock); 1961da177e4SLinus Torvalds 197bc578a54SJoe Perches if (qp->q.last_in & INET_FRAG_COMPLETE) 1981da177e4SLinus Torvalds goto out; 1991da177e4SLinus Torvalds 2001da177e4SLinus Torvalds ipq_kill(qp); 2011da177e4SLinus Torvalds 2027c73a6faSPavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMTIMEOUT); 2037c73a6faSPavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 2041da177e4SLinus Torvalds 205bc578a54SJoe Perches if ((qp->q.last_in & INET_FRAG_FIRST_IN) && qp->q.fragments != NULL) { 2065ab11c98SPavel Emelyanov struct sk_buff *head = qp->q.fragments; 207cb84663eSDenis V. Lunev 2081da177e4SLinus Torvalds /* Send an ICMP "Fragment Reassembly Timeout" message. */ 209cb84663eSDenis V. Lunev if ((head->dev = dev_get_by_index(net, qp->iif)) != NULL) { 2101da177e4SLinus Torvalds icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0); 2111da177e4SLinus Torvalds dev_put(head->dev); 2121da177e4SLinus Torvalds } 2131da177e4SLinus Torvalds } 2141da177e4SLinus Torvalds out: 2155ab11c98SPavel Emelyanov spin_unlock(&qp->q.lock); 2164b6cb5d8SPavel Emelyanov ipq_put(qp); 2171da177e4SLinus Torvalds } 2181da177e4SLinus Torvalds 219abd6523dSPavel Emelyanov /* Find the correct entry in the "incomplete datagrams" queue for 220abd6523dSPavel Emelyanov * this IP datagram, and create new one, if nothing is found. 221abd6523dSPavel Emelyanov */ 222ac18e750SPavel Emelyanov static inline struct ipq *ip_find(struct net *net, struct iphdr *iph, u32 user) 2231da177e4SLinus Torvalds { 224c6fda282SPavel Emelyanov struct inet_frag_queue *q; 225c6fda282SPavel Emelyanov struct ip4_create_arg arg; 226abd6523dSPavel Emelyanov unsigned int hash; 2271da177e4SLinus Torvalds 228c6fda282SPavel Emelyanov arg.iph = iph; 229c6fda282SPavel Emelyanov arg.user = user; 2309a375803SPavel Emelyanov 2319a375803SPavel Emelyanov read_lock(&ip4_frags.lock); 232abd6523dSPavel Emelyanov hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol); 233c6fda282SPavel Emelyanov 234ac18e750SPavel Emelyanov q = inet_frag_find(&net->ipv4.frags, &ip4_frags, &arg, hash); 235c6fda282SPavel Emelyanov if (q == NULL) 2361da177e4SLinus Torvalds goto out_nomem; 2371da177e4SLinus Torvalds 238c6fda282SPavel Emelyanov return container_of(q, struct ipq, q); 2391da177e4SLinus Torvalds 2401da177e4SLinus Torvalds out_nomem: 24164ce2073SPatrick McHardy LIMIT_NETDEBUG(KERN_ERR "ip_frag_create: no memory left !\n"); 2421da177e4SLinus Torvalds return NULL; 2431da177e4SLinus Torvalds } 2441da177e4SLinus Torvalds 24589cee8b1SHerbert Xu /* Is the fragment too far ahead to be part of ipq? */ 24689cee8b1SHerbert Xu static inline int ip_frag_too_far(struct ipq *qp) 24789cee8b1SHerbert Xu { 24889cee8b1SHerbert Xu struct inet_peer *peer = qp->peer; 24989cee8b1SHerbert Xu unsigned int max = sysctl_ipfrag_max_dist; 25089cee8b1SHerbert Xu unsigned int start, end; 25189cee8b1SHerbert Xu 25289cee8b1SHerbert Xu int rc; 25389cee8b1SHerbert Xu 25489cee8b1SHerbert Xu if (!peer || !max) 25589cee8b1SHerbert Xu return 0; 25689cee8b1SHerbert Xu 25789cee8b1SHerbert Xu start = qp->rid; 25889cee8b1SHerbert Xu end = atomic_inc_return(&peer->rid); 25989cee8b1SHerbert Xu qp->rid = end; 26089cee8b1SHerbert Xu 2615ab11c98SPavel Emelyanov rc = qp->q.fragments && (end - start) > max; 26289cee8b1SHerbert Xu 26389cee8b1SHerbert Xu if (rc) { 2647c73a6faSPavel Emelyanov struct net *net; 2657c73a6faSPavel Emelyanov 2667c73a6faSPavel Emelyanov net = container_of(qp->q.net, struct net, ipv4.frags); 2677c73a6faSPavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 26889cee8b1SHerbert Xu } 26989cee8b1SHerbert Xu 27089cee8b1SHerbert Xu return rc; 27189cee8b1SHerbert Xu } 27289cee8b1SHerbert Xu 27389cee8b1SHerbert Xu static int ip_frag_reinit(struct ipq *qp) 27489cee8b1SHerbert Xu { 27589cee8b1SHerbert Xu struct sk_buff *fp; 27689cee8b1SHerbert Xu 277b2fd5321SPavel Emelyanov if (!mod_timer(&qp->q.timer, jiffies + qp->q.net->timeout)) { 2785ab11c98SPavel Emelyanov atomic_inc(&qp->q.refcnt); 27989cee8b1SHerbert Xu return -ETIMEDOUT; 28089cee8b1SHerbert Xu } 28189cee8b1SHerbert Xu 2825ab11c98SPavel Emelyanov fp = qp->q.fragments; 28389cee8b1SHerbert Xu do { 28489cee8b1SHerbert Xu struct sk_buff *xp = fp->next; 2856ddc0822SPavel Emelyanov frag_kfree_skb(qp->q.net, fp, NULL); 28689cee8b1SHerbert Xu fp = xp; 28789cee8b1SHerbert Xu } while (fp); 28889cee8b1SHerbert Xu 2895ab11c98SPavel Emelyanov qp->q.last_in = 0; 2905ab11c98SPavel Emelyanov qp->q.len = 0; 2915ab11c98SPavel Emelyanov qp->q.meat = 0; 2925ab11c98SPavel Emelyanov qp->q.fragments = NULL; 29389cee8b1SHerbert Xu qp->iif = 0; 29489cee8b1SHerbert Xu 29589cee8b1SHerbert Xu return 0; 29689cee8b1SHerbert Xu } 29789cee8b1SHerbert Xu 2981da177e4SLinus Torvalds /* Add new segment to existing queue. */ 2991706d587SHerbert Xu static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb) 3001da177e4SLinus Torvalds { 3011da177e4SLinus Torvalds struct sk_buff *prev, *next; 3021706d587SHerbert Xu struct net_device *dev; 3031da177e4SLinus Torvalds int flags, offset; 3041da177e4SLinus Torvalds int ihl, end; 3051706d587SHerbert Xu int err = -ENOENT; 3061da177e4SLinus Torvalds 307bc578a54SJoe Perches if (qp->q.last_in & INET_FRAG_COMPLETE) 3081da177e4SLinus Torvalds goto err; 3091da177e4SLinus Torvalds 31089cee8b1SHerbert Xu if (!(IPCB(skb)->flags & IPSKB_FRAG_COMPLETE) && 3111706d587SHerbert Xu unlikely(ip_frag_too_far(qp)) && 3121706d587SHerbert Xu unlikely(err = ip_frag_reinit(qp))) { 31389cee8b1SHerbert Xu ipq_kill(qp); 31489cee8b1SHerbert Xu goto err; 31589cee8b1SHerbert Xu } 31689cee8b1SHerbert Xu 317eddc9ec5SArnaldo Carvalho de Melo offset = ntohs(ip_hdr(skb)->frag_off); 3181da177e4SLinus Torvalds flags = offset & ~IP_OFFSET; 3191da177e4SLinus Torvalds offset &= IP_OFFSET; 3201da177e4SLinus Torvalds offset <<= 3; /* offset is in 8-byte chunks */ 321c9bdd4b5SArnaldo Carvalho de Melo ihl = ip_hdrlen(skb); 3221da177e4SLinus Torvalds 3231da177e4SLinus Torvalds /* Determine the position of this fragment. */ 3241da177e4SLinus Torvalds end = offset + skb->len - ihl; 3251706d587SHerbert Xu err = -EINVAL; 3261da177e4SLinus Torvalds 3271da177e4SLinus Torvalds /* Is this the final fragment? */ 3281da177e4SLinus Torvalds if ((flags & IP_MF) == 0) { 3291da177e4SLinus Torvalds /* If we already have some bits beyond end 3301da177e4SLinus Torvalds * or have different end, the segment is corrrupted. 3311da177e4SLinus Torvalds */ 3325ab11c98SPavel Emelyanov if (end < qp->q.len || 333bc578a54SJoe Perches ((qp->q.last_in & INET_FRAG_LAST_IN) && end != qp->q.len)) 3341da177e4SLinus Torvalds goto err; 335bc578a54SJoe Perches qp->q.last_in |= INET_FRAG_LAST_IN; 3365ab11c98SPavel Emelyanov qp->q.len = end; 3371da177e4SLinus Torvalds } else { 3381da177e4SLinus Torvalds if (end&7) { 3391da177e4SLinus Torvalds end &= ~7; 3401da177e4SLinus Torvalds if (skb->ip_summed != CHECKSUM_UNNECESSARY) 3411da177e4SLinus Torvalds skb->ip_summed = CHECKSUM_NONE; 3421da177e4SLinus Torvalds } 3435ab11c98SPavel Emelyanov if (end > qp->q.len) { 3441da177e4SLinus Torvalds /* Some bits beyond end -> corruption. */ 345bc578a54SJoe Perches if (qp->q.last_in & INET_FRAG_LAST_IN) 3461da177e4SLinus Torvalds goto err; 3475ab11c98SPavel Emelyanov qp->q.len = end; 3481da177e4SLinus Torvalds } 3491da177e4SLinus Torvalds } 3501da177e4SLinus Torvalds if (end == offset) 3511da177e4SLinus Torvalds goto err; 3521da177e4SLinus Torvalds 3531706d587SHerbert Xu err = -ENOMEM; 3541da177e4SLinus Torvalds if (pskb_pull(skb, ihl) == NULL) 3551da177e4SLinus Torvalds goto err; 3561706d587SHerbert Xu 3571706d587SHerbert Xu err = pskb_trim_rcsum(skb, end - offset); 3581706d587SHerbert Xu if (err) 3591da177e4SLinus Torvalds goto err; 3601da177e4SLinus Torvalds 3611da177e4SLinus Torvalds /* Find out which fragments are in front and at the back of us 3621da177e4SLinus Torvalds * in the chain of fragments so far. We must know where to put 3631da177e4SLinus Torvalds * this fragment, right? 3641da177e4SLinus Torvalds */ 3651da177e4SLinus Torvalds prev = NULL; 3665ab11c98SPavel Emelyanov for (next = qp->q.fragments; next != NULL; next = next->next) { 3671da177e4SLinus Torvalds if (FRAG_CB(next)->offset >= offset) 3681da177e4SLinus Torvalds break; /* bingo! */ 3691da177e4SLinus Torvalds prev = next; 3701da177e4SLinus Torvalds } 3711da177e4SLinus Torvalds 3721da177e4SLinus Torvalds /* We found where to put this one. Check for overlap with 3731da177e4SLinus Torvalds * preceding fragment, and, if needed, align things so that 3741da177e4SLinus Torvalds * any overlaps are eliminated. 3751da177e4SLinus Torvalds */ 3761da177e4SLinus Torvalds if (prev) { 3771da177e4SLinus Torvalds int i = (FRAG_CB(prev)->offset + prev->len) - offset; 3781da177e4SLinus Torvalds 3791da177e4SLinus Torvalds if (i > 0) { 3801da177e4SLinus Torvalds offset += i; 3811706d587SHerbert Xu err = -EINVAL; 3821da177e4SLinus Torvalds if (end <= offset) 3831da177e4SLinus Torvalds goto err; 3841706d587SHerbert Xu err = -ENOMEM; 3851da177e4SLinus Torvalds if (!pskb_pull(skb, i)) 3861da177e4SLinus Torvalds goto err; 3871da177e4SLinus Torvalds if (skb->ip_summed != CHECKSUM_UNNECESSARY) 3881da177e4SLinus Torvalds skb->ip_summed = CHECKSUM_NONE; 3891da177e4SLinus Torvalds } 3901da177e4SLinus Torvalds } 3911da177e4SLinus Torvalds 3921706d587SHerbert Xu err = -ENOMEM; 3931706d587SHerbert Xu 3941da177e4SLinus Torvalds while (next && FRAG_CB(next)->offset < end) { 3951da177e4SLinus Torvalds int i = end - FRAG_CB(next)->offset; /* overlap is 'i' bytes */ 3961da177e4SLinus Torvalds 3971da177e4SLinus Torvalds if (i < next->len) { 3981da177e4SLinus Torvalds /* Eat head of the next overlapped fragment 3991da177e4SLinus Torvalds * and leave the loop. The next ones cannot overlap. 4001da177e4SLinus Torvalds */ 4011da177e4SLinus Torvalds if (!pskb_pull(next, i)) 4021da177e4SLinus Torvalds goto err; 4031da177e4SLinus Torvalds FRAG_CB(next)->offset += i; 4045ab11c98SPavel Emelyanov qp->q.meat -= i; 4051da177e4SLinus Torvalds if (next->ip_summed != CHECKSUM_UNNECESSARY) 4061da177e4SLinus Torvalds next->ip_summed = CHECKSUM_NONE; 4071da177e4SLinus Torvalds break; 4081da177e4SLinus Torvalds } else { 4091da177e4SLinus Torvalds struct sk_buff *free_it = next; 4101da177e4SLinus Torvalds 41147c6bf77SPeter Zijlstra /* Old fragment is completely overridden with 4121da177e4SLinus Torvalds * new one drop it. 4131da177e4SLinus Torvalds */ 4141da177e4SLinus Torvalds next = next->next; 4151da177e4SLinus Torvalds 4161da177e4SLinus Torvalds if (prev) 4171da177e4SLinus Torvalds prev->next = next; 4181da177e4SLinus Torvalds else 4195ab11c98SPavel Emelyanov qp->q.fragments = next; 4201da177e4SLinus Torvalds 4215ab11c98SPavel Emelyanov qp->q.meat -= free_it->len; 4226ddc0822SPavel Emelyanov frag_kfree_skb(qp->q.net, free_it, NULL); 4231da177e4SLinus Torvalds } 4241da177e4SLinus Torvalds } 4251da177e4SLinus Torvalds 4261da177e4SLinus Torvalds FRAG_CB(skb)->offset = offset; 4271da177e4SLinus Torvalds 4281da177e4SLinus Torvalds /* Insert this fragment in the chain of fragments. */ 4291da177e4SLinus Torvalds skb->next = next; 4301da177e4SLinus Torvalds if (prev) 4311da177e4SLinus Torvalds prev->next = skb; 4321da177e4SLinus Torvalds else 4335ab11c98SPavel Emelyanov qp->q.fragments = skb; 4341da177e4SLinus Torvalds 4351706d587SHerbert Xu dev = skb->dev; 4361706d587SHerbert Xu if (dev) { 4371706d587SHerbert Xu qp->iif = dev->ifindex; 4381da177e4SLinus Torvalds skb->dev = NULL; 4391706d587SHerbert Xu } 4405ab11c98SPavel Emelyanov qp->q.stamp = skb->tstamp; 4415ab11c98SPavel Emelyanov qp->q.meat += skb->len; 4426ddc0822SPavel Emelyanov atomic_add(skb->truesize, &qp->q.net->mem); 4431da177e4SLinus Torvalds if (offset == 0) 444bc578a54SJoe Perches qp->q.last_in |= INET_FRAG_FIRST_IN; 4451da177e4SLinus Torvalds 446bc578a54SJoe Perches if (qp->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && 447bc578a54SJoe Perches qp->q.meat == qp->q.len) 4481706d587SHerbert Xu return ip_frag_reasm(qp, prev, dev); 4491706d587SHerbert Xu 4507eb95156SPavel Emelyanov write_lock(&ip4_frags.lock); 4513140c25cSPavel Emelyanov list_move_tail(&qp->q.lru_list, &qp->q.net->lru_list); 4527eb95156SPavel Emelyanov write_unlock(&ip4_frags.lock); 4531706d587SHerbert Xu return -EINPROGRESS; 4541da177e4SLinus Torvalds 4551da177e4SLinus Torvalds err: 4561da177e4SLinus Torvalds kfree_skb(skb); 4571706d587SHerbert Xu return err; 4581da177e4SLinus Torvalds } 4591da177e4SLinus Torvalds 4601da177e4SLinus Torvalds 4611da177e4SLinus Torvalds /* Build a new IP datagram from all its fragments. */ 4621da177e4SLinus Torvalds 4631706d587SHerbert Xu static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, 4641706d587SHerbert Xu struct net_device *dev) 4651da177e4SLinus Torvalds { 4662bad35b7SJorge Boncompte [DTI2] struct net *net = container_of(qp->q.net, struct net, ipv4.frags); 4671da177e4SLinus Torvalds struct iphdr *iph; 4685ab11c98SPavel Emelyanov struct sk_buff *fp, *head = qp->q.fragments; 4691da177e4SLinus Torvalds int len; 4701da177e4SLinus Torvalds int ihlen; 4711706d587SHerbert Xu int err; 4721da177e4SLinus Torvalds 4731da177e4SLinus Torvalds ipq_kill(qp); 4741da177e4SLinus Torvalds 4751706d587SHerbert Xu /* Make the one we just received the head. */ 4761706d587SHerbert Xu if (prev) { 4771706d587SHerbert Xu head = prev->next; 4781706d587SHerbert Xu fp = skb_clone(head, GFP_ATOMIC); 4791706d587SHerbert Xu if (!fp) 4801706d587SHerbert Xu goto out_nomem; 4811706d587SHerbert Xu 4821706d587SHerbert Xu fp->next = head->next; 4831706d587SHerbert Xu prev->next = fp; 4841706d587SHerbert Xu 4855ab11c98SPavel Emelyanov skb_morph(head, qp->q.fragments); 4865ab11c98SPavel Emelyanov head->next = qp->q.fragments->next; 4871706d587SHerbert Xu 4885ab11c98SPavel Emelyanov kfree_skb(qp->q.fragments); 4895ab11c98SPavel Emelyanov qp->q.fragments = head; 4901706d587SHerbert Xu } 4911706d587SHerbert Xu 492547b792cSIlpo Järvinen WARN_ON(head == NULL); 493547b792cSIlpo Järvinen WARN_ON(FRAG_CB(head)->offset != 0); 4941da177e4SLinus Torvalds 4951da177e4SLinus Torvalds /* Allocate a new buffer for the datagram. */ 496c9bdd4b5SArnaldo Carvalho de Melo ihlen = ip_hdrlen(head); 4975ab11c98SPavel Emelyanov len = ihlen + qp->q.len; 4981da177e4SLinus Torvalds 4991706d587SHerbert Xu err = -E2BIG; 5001da177e4SLinus Torvalds if (len > 65535) 5011da177e4SLinus Torvalds goto out_oversize; 5021da177e4SLinus Torvalds 5031da177e4SLinus Torvalds /* Head of list must not be cloned. */ 5041da177e4SLinus Torvalds if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) 5051da177e4SLinus Torvalds goto out_nomem; 5061da177e4SLinus Torvalds 5071da177e4SLinus Torvalds /* If the first fragment is fragmented itself, we split 5081da177e4SLinus Torvalds * it to two chunks: the first with data and paged part 5091da177e4SLinus Torvalds * and the second, holding only fragments. */ 5101da177e4SLinus Torvalds if (skb_shinfo(head)->frag_list) { 5111da177e4SLinus Torvalds struct sk_buff *clone; 5121da177e4SLinus Torvalds int i, plen = 0; 5131da177e4SLinus Torvalds 5141da177e4SLinus Torvalds if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) 5151da177e4SLinus Torvalds goto out_nomem; 5161da177e4SLinus Torvalds clone->next = head->next; 5171da177e4SLinus Torvalds head->next = clone; 5181da177e4SLinus Torvalds skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; 5191da177e4SLinus Torvalds skb_shinfo(head)->frag_list = NULL; 5201da177e4SLinus Torvalds for (i=0; i<skb_shinfo(head)->nr_frags; i++) 5211da177e4SLinus Torvalds plen += skb_shinfo(head)->frags[i].size; 5221da177e4SLinus Torvalds clone->len = clone->data_len = head->data_len - plen; 5231da177e4SLinus Torvalds head->data_len -= clone->len; 5241da177e4SLinus Torvalds head->len -= clone->len; 5251da177e4SLinus Torvalds clone->csum = 0; 5261da177e4SLinus Torvalds clone->ip_summed = head->ip_summed; 5276ddc0822SPavel Emelyanov atomic_add(clone->truesize, &qp->q.net->mem); 5281da177e4SLinus Torvalds } 5291da177e4SLinus Torvalds 5301da177e4SLinus Torvalds skb_shinfo(head)->frag_list = head->next; 531d56f90a7SArnaldo Carvalho de Melo skb_push(head, head->data - skb_network_header(head)); 5326ddc0822SPavel Emelyanov atomic_sub(head->truesize, &qp->q.net->mem); 5331da177e4SLinus Torvalds 5341da177e4SLinus Torvalds for (fp=head->next; fp; fp = fp->next) { 5351da177e4SLinus Torvalds head->data_len += fp->len; 5361da177e4SLinus Torvalds head->len += fp->len; 5371da177e4SLinus Torvalds if (head->ip_summed != fp->ip_summed) 5381da177e4SLinus Torvalds head->ip_summed = CHECKSUM_NONE; 53984fa7933SPatrick McHardy else if (head->ip_summed == CHECKSUM_COMPLETE) 5401da177e4SLinus Torvalds head->csum = csum_add(head->csum, fp->csum); 5411da177e4SLinus Torvalds head->truesize += fp->truesize; 5426ddc0822SPavel Emelyanov atomic_sub(fp->truesize, &qp->q.net->mem); 5431da177e4SLinus Torvalds } 5441da177e4SLinus Torvalds 5451da177e4SLinus Torvalds head->next = NULL; 5461da177e4SLinus Torvalds head->dev = dev; 5475ab11c98SPavel Emelyanov head->tstamp = qp->q.stamp; 5481da177e4SLinus Torvalds 549eddc9ec5SArnaldo Carvalho de Melo iph = ip_hdr(head); 5501da177e4SLinus Torvalds iph->frag_off = 0; 5511da177e4SLinus Torvalds iph->tot_len = htons(len); 5522bad35b7SJorge Boncompte [DTI2] IP_INC_STATS_BH(net, IPSTATS_MIB_REASMOKS); 5535ab11c98SPavel Emelyanov qp->q.fragments = NULL; 5541706d587SHerbert Xu return 0; 5551da177e4SLinus Torvalds 5561da177e4SLinus Torvalds out_nomem: 55764ce2073SPatrick McHardy LIMIT_NETDEBUG(KERN_ERR "IP: queue_glue: no memory for gluing " 55864ce2073SPatrick McHardy "queue %p\n", qp); 55945542479SDavid Howells err = -ENOMEM; 5601da177e4SLinus Torvalds goto out_fail; 5611da177e4SLinus Torvalds out_oversize: 5621da177e4SLinus Torvalds if (net_ratelimit()) 563673d57e7SHarvey Harrison printk(KERN_INFO "Oversized IP packet from %pI4.\n", 564673d57e7SHarvey Harrison &qp->saddr); 5651da177e4SLinus Torvalds out_fail: 5667c73a6faSPavel Emelyanov IP_INC_STATS_BH(dev_net(dev), IPSTATS_MIB_REASMFAILS); 5671706d587SHerbert Xu return err; 5681da177e4SLinus Torvalds } 5691da177e4SLinus Torvalds 5701da177e4SLinus Torvalds /* Process an incoming IP datagram fragment. */ 571776c729eSHerbert Xu int ip_defrag(struct sk_buff *skb, u32 user) 5721da177e4SLinus Torvalds { 5731da177e4SLinus Torvalds struct ipq *qp; 574ac18e750SPavel Emelyanov struct net *net; 5751da177e4SLinus Torvalds 57684a3aa00SPavel Emelyanov net = skb->dev ? dev_net(skb->dev) : dev_net(skb->dst->dev); 5777c73a6faSPavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMREQDS); 5781da177e4SLinus Torvalds 5791da177e4SLinus Torvalds /* Start by cleaning up the memory. */ 580e31e0bdcSPavel Emelyanov if (atomic_read(&net->ipv4.frags.mem) > net->ipv4.frags.high_thresh) 5816ddc0822SPavel Emelyanov ip_evictor(net); 5821da177e4SLinus Torvalds 5831da177e4SLinus Torvalds /* Lookup (or create) queue header */ 584ac18e750SPavel Emelyanov if ((qp = ip_find(net, ip_hdr(skb), user)) != NULL) { 5851706d587SHerbert Xu int ret; 5861da177e4SLinus Torvalds 5875ab11c98SPavel Emelyanov spin_lock(&qp->q.lock); 5881da177e4SLinus Torvalds 5891706d587SHerbert Xu ret = ip_frag_queue(qp, skb); 5901da177e4SLinus Torvalds 5915ab11c98SPavel Emelyanov spin_unlock(&qp->q.lock); 5924b6cb5d8SPavel Emelyanov ipq_put(qp); 593776c729eSHerbert Xu return ret; 5941da177e4SLinus Torvalds } 5951da177e4SLinus Torvalds 5967c73a6faSPavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 5971da177e4SLinus Torvalds kfree_skb(skb); 598776c729eSHerbert Xu return -ENOMEM; 5991da177e4SLinus Torvalds } 6001da177e4SLinus Torvalds 6018d8354d2SPavel Emelyanov #ifdef CONFIG_SYSCTL 6028d8354d2SPavel Emelyanov static int zero; 6038d8354d2SPavel Emelyanov 6040a64b4b8SPavel Emelyanov static struct ctl_table ip4_frags_ns_ctl_table[] = { 6058d8354d2SPavel Emelyanov { 6068d8354d2SPavel Emelyanov .ctl_name = NET_IPV4_IPFRAG_HIGH_THRESH, 6078d8354d2SPavel Emelyanov .procname = "ipfrag_high_thresh", 608e31e0bdcSPavel Emelyanov .data = &init_net.ipv4.frags.high_thresh, 6098d8354d2SPavel Emelyanov .maxlen = sizeof(int), 6108d8354d2SPavel Emelyanov .mode = 0644, 6116d9f239aSAlexey Dobriyan .proc_handler = proc_dointvec 6128d8354d2SPavel Emelyanov }, 6138d8354d2SPavel Emelyanov { 6148d8354d2SPavel Emelyanov .ctl_name = NET_IPV4_IPFRAG_LOW_THRESH, 6158d8354d2SPavel Emelyanov .procname = "ipfrag_low_thresh", 616e31e0bdcSPavel Emelyanov .data = &init_net.ipv4.frags.low_thresh, 6178d8354d2SPavel Emelyanov .maxlen = sizeof(int), 6188d8354d2SPavel Emelyanov .mode = 0644, 6196d9f239aSAlexey Dobriyan .proc_handler = proc_dointvec 6208d8354d2SPavel Emelyanov }, 6218d8354d2SPavel Emelyanov { 6228d8354d2SPavel Emelyanov .ctl_name = NET_IPV4_IPFRAG_TIME, 6238d8354d2SPavel Emelyanov .procname = "ipfrag_time", 624b2fd5321SPavel Emelyanov .data = &init_net.ipv4.frags.timeout, 6258d8354d2SPavel Emelyanov .maxlen = sizeof(int), 6268d8354d2SPavel Emelyanov .mode = 0644, 6276d9f239aSAlexey Dobriyan .proc_handler = proc_dointvec_jiffies, 6286d9f239aSAlexey Dobriyan .strategy = sysctl_jiffies 6298d8354d2SPavel Emelyanov }, 6307d291ebbSPavel Emelyanov { } 6317d291ebbSPavel Emelyanov }; 6327d291ebbSPavel Emelyanov 6337d291ebbSPavel Emelyanov static struct ctl_table ip4_frags_ctl_table[] = { 6348d8354d2SPavel Emelyanov { 6358d8354d2SPavel Emelyanov .ctl_name = NET_IPV4_IPFRAG_SECRET_INTERVAL, 6368d8354d2SPavel Emelyanov .procname = "ipfrag_secret_interval", 6373b4bc4a2SPavel Emelyanov .data = &ip4_frags.secret_interval, 6388d8354d2SPavel Emelyanov .maxlen = sizeof(int), 6398d8354d2SPavel Emelyanov .mode = 0644, 6406d9f239aSAlexey Dobriyan .proc_handler = proc_dointvec_jiffies, 6416d9f239aSAlexey Dobriyan .strategy = sysctl_jiffies 6428d8354d2SPavel Emelyanov }, 6438d8354d2SPavel Emelyanov { 6448d8354d2SPavel Emelyanov .procname = "ipfrag_max_dist", 6458d8354d2SPavel Emelyanov .data = &sysctl_ipfrag_max_dist, 6468d8354d2SPavel Emelyanov .maxlen = sizeof(int), 6478d8354d2SPavel Emelyanov .mode = 0644, 6486d9f239aSAlexey Dobriyan .proc_handler = proc_dointvec_minmax, 6498d8354d2SPavel Emelyanov .extra1 = &zero 6508d8354d2SPavel Emelyanov }, 6518d8354d2SPavel Emelyanov { } 6528d8354d2SPavel Emelyanov }; 6538d8354d2SPavel Emelyanov 6540a64b4b8SPavel Emelyanov static int ip4_frags_ns_ctl_register(struct net *net) 6558d8354d2SPavel Emelyanov { 656e4a2d5c2SPavel Emelyanov struct ctl_table *table; 6578d8354d2SPavel Emelyanov struct ctl_table_header *hdr; 6588d8354d2SPavel Emelyanov 6590a64b4b8SPavel Emelyanov table = ip4_frags_ns_ctl_table; 660e4a2d5c2SPavel Emelyanov if (net != &init_net) { 6610a64b4b8SPavel Emelyanov table = kmemdup(table, sizeof(ip4_frags_ns_ctl_table), GFP_KERNEL); 662e4a2d5c2SPavel Emelyanov if (table == NULL) 663e4a2d5c2SPavel Emelyanov goto err_alloc; 664e4a2d5c2SPavel Emelyanov 665e31e0bdcSPavel Emelyanov table[0].data = &net->ipv4.frags.high_thresh; 666e31e0bdcSPavel Emelyanov table[1].data = &net->ipv4.frags.low_thresh; 667b2fd5321SPavel Emelyanov table[2].data = &net->ipv4.frags.timeout; 668e4a2d5c2SPavel Emelyanov } 669e4a2d5c2SPavel Emelyanov 670e4a2d5c2SPavel Emelyanov hdr = register_net_sysctl_table(net, net_ipv4_ctl_path, table); 671e4a2d5c2SPavel Emelyanov if (hdr == NULL) 672e4a2d5c2SPavel Emelyanov goto err_reg; 673e4a2d5c2SPavel Emelyanov 674e4a2d5c2SPavel Emelyanov net->ipv4.frags_hdr = hdr; 675e4a2d5c2SPavel Emelyanov return 0; 676e4a2d5c2SPavel Emelyanov 677e4a2d5c2SPavel Emelyanov err_reg: 678e4a2d5c2SPavel Emelyanov if (net != &init_net) 679e4a2d5c2SPavel Emelyanov kfree(table); 680e4a2d5c2SPavel Emelyanov err_alloc: 681e4a2d5c2SPavel Emelyanov return -ENOMEM; 682e4a2d5c2SPavel Emelyanov } 683e4a2d5c2SPavel Emelyanov 6840a64b4b8SPavel Emelyanov static void ip4_frags_ns_ctl_unregister(struct net *net) 685e4a2d5c2SPavel Emelyanov { 686e4a2d5c2SPavel Emelyanov struct ctl_table *table; 687e4a2d5c2SPavel Emelyanov 688e4a2d5c2SPavel Emelyanov table = net->ipv4.frags_hdr->ctl_table_arg; 689e4a2d5c2SPavel Emelyanov unregister_net_sysctl_table(net->ipv4.frags_hdr); 690e4a2d5c2SPavel Emelyanov kfree(table); 6918d8354d2SPavel Emelyanov } 6927d291ebbSPavel Emelyanov 6937d291ebbSPavel Emelyanov static void ip4_frags_ctl_register(void) 6947d291ebbSPavel Emelyanov { 6957d291ebbSPavel Emelyanov register_net_sysctl_rotable(net_ipv4_ctl_path, ip4_frags_ctl_table); 6967d291ebbSPavel Emelyanov } 6978d8354d2SPavel Emelyanov #else 6980a64b4b8SPavel Emelyanov static inline int ip4_frags_ns_ctl_register(struct net *net) 6998d8354d2SPavel Emelyanov { 7008d8354d2SPavel Emelyanov return 0; 7018d8354d2SPavel Emelyanov } 702e4a2d5c2SPavel Emelyanov 7030a64b4b8SPavel Emelyanov static inline void ip4_frags_ns_ctl_unregister(struct net *net) 704e4a2d5c2SPavel Emelyanov { 705e4a2d5c2SPavel Emelyanov } 7067d291ebbSPavel Emelyanov 7077d291ebbSPavel Emelyanov static inline void ip4_frags_ctl_register(void) 7087d291ebbSPavel Emelyanov { 7097d291ebbSPavel Emelyanov } 7108d8354d2SPavel Emelyanov #endif 7118d8354d2SPavel Emelyanov 7128d8354d2SPavel Emelyanov static int ipv4_frags_init_net(struct net *net) 7138d8354d2SPavel Emelyanov { 714b2fd5321SPavel Emelyanov /* 715e31e0bdcSPavel Emelyanov * Fragment cache limits. We will commit 256K at one time. Should we 716e31e0bdcSPavel Emelyanov * cross that limit we will prune down to 192K. This should cope with 717e31e0bdcSPavel Emelyanov * even the most extreme cases without allowing an attacker to 718e31e0bdcSPavel Emelyanov * measurably harm machine performance. 719e31e0bdcSPavel Emelyanov */ 720e31e0bdcSPavel Emelyanov net->ipv4.frags.high_thresh = 256 * 1024; 721e31e0bdcSPavel Emelyanov net->ipv4.frags.low_thresh = 192 * 1024; 722e31e0bdcSPavel Emelyanov /* 723b2fd5321SPavel Emelyanov * Important NOTE! Fragment queue must be destroyed before MSL expires. 724b2fd5321SPavel Emelyanov * RFC791 is wrong proposing to prolongate timer each fragment arrival 725b2fd5321SPavel Emelyanov * by TTL. 726b2fd5321SPavel Emelyanov */ 727b2fd5321SPavel Emelyanov net->ipv4.frags.timeout = IP_FRAG_TIME; 728b2fd5321SPavel Emelyanov 729e5a2bb84SPavel Emelyanov inet_frags_init_net(&net->ipv4.frags); 730e5a2bb84SPavel Emelyanov 7310a64b4b8SPavel Emelyanov return ip4_frags_ns_ctl_register(net); 7328d8354d2SPavel Emelyanov } 7338d8354d2SPavel Emelyanov 73481566e83SPavel Emelyanov static void ipv4_frags_exit_net(struct net *net) 73581566e83SPavel Emelyanov { 7360a64b4b8SPavel Emelyanov ip4_frags_ns_ctl_unregister(net); 73781566e83SPavel Emelyanov inet_frags_exit_net(&net->ipv4.frags, &ip4_frags); 73881566e83SPavel Emelyanov } 73981566e83SPavel Emelyanov 74081566e83SPavel Emelyanov static struct pernet_operations ip4_frags_ops = { 74181566e83SPavel Emelyanov .init = ipv4_frags_init_net, 74281566e83SPavel Emelyanov .exit = ipv4_frags_exit_net, 74381566e83SPavel Emelyanov }; 74481566e83SPavel Emelyanov 745b7aa0bf7SEric Dumazet void __init ipfrag_init(void) 7461da177e4SLinus Torvalds { 7477d291ebbSPavel Emelyanov ip4_frags_ctl_register(); 74881566e83SPavel Emelyanov register_pernet_subsys(&ip4_frags_ops); 749321a3a99SPavel Emelyanov ip4_frags.hashfn = ip4_hashfn; 750c6fda282SPavel Emelyanov ip4_frags.constructor = ip4_frag_init; 7511e4b8287SPavel Emelyanov ip4_frags.destructor = ip4_frag_free; 7521e4b8287SPavel Emelyanov ip4_frags.skb_free = NULL; 7531e4b8287SPavel Emelyanov ip4_frags.qsize = sizeof(struct ipq); 754abd6523dSPavel Emelyanov ip4_frags.match = ip4_frag_match; 755e521db9dSPavel Emelyanov ip4_frags.frag_expire = ip_expire; 7563b4bc4a2SPavel Emelyanov ip4_frags.secret_interval = 10 * 60 * HZ; 7577eb95156SPavel Emelyanov inet_frags_init(&ip4_frags); 7581da177e4SLinus Torvalds } 7591da177e4SLinus Torvalds 7601da177e4SLinus Torvalds EXPORT_SYMBOL(ip_defrag); 761