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> 355a0e3ad6STejun Heo #include <linux/slab.h> 36e9017b55SShan Wei #include <net/route.h> 37e9017b55SShan Wei #include <net/dst.h> 381da177e4SLinus Torvalds #include <net/sock.h> 391da177e4SLinus Torvalds #include <net/ip.h> 401da177e4SLinus Torvalds #include <net/icmp.h> 411da177e4SLinus Torvalds #include <net/checksum.h> 4289cee8b1SHerbert Xu #include <net/inetpeer.h> 435ab11c98SPavel Emelyanov #include <net/inet_frag.h> 441da177e4SLinus Torvalds #include <linux/tcp.h> 451da177e4SLinus Torvalds #include <linux/udp.h> 461da177e4SLinus Torvalds #include <linux/inet.h> 471da177e4SLinus Torvalds #include <linux/netfilter_ipv4.h> 481da177e4SLinus Torvalds 491da177e4SLinus Torvalds /* NOTE. Logic of IP defragmentation is parallel to corresponding IPv6 501da177e4SLinus Torvalds * code now. If you change something here, _PLEASE_ update ipv6/reassembly.c 511da177e4SLinus Torvalds * as well. Or notify me, at least. --ANK 521da177e4SLinus Torvalds */ 531da177e4SLinus Torvalds 548d8354d2SPavel Emelyanov static int sysctl_ipfrag_max_dist __read_mostly = 64; 5589cee8b1SHerbert Xu 561da177e4SLinus Torvalds struct ipfrag_skb_cb 571da177e4SLinus Torvalds { 581da177e4SLinus Torvalds struct inet_skb_parm h; 591da177e4SLinus Torvalds int offset; 601da177e4SLinus Torvalds }; 611da177e4SLinus Torvalds 621da177e4SLinus Torvalds #define FRAG_CB(skb) ((struct ipfrag_skb_cb *)((skb)->cb)) 631da177e4SLinus Torvalds 641da177e4SLinus Torvalds /* Describe an entry in the "incomplete datagrams" queue. */ 651da177e4SLinus Torvalds struct ipq { 665ab11c98SPavel Emelyanov struct inet_frag_queue q; 675ab11c98SPavel Emelyanov 681da177e4SLinus Torvalds u32 user; 6918277770SAl Viro __be32 saddr; 7018277770SAl Viro __be32 daddr; 7118277770SAl Viro __be16 id; 721da177e4SLinus Torvalds u8 protocol; 7389cee8b1SHerbert Xu int iif; 7489cee8b1SHerbert Xu unsigned int rid; 7589cee8b1SHerbert Xu struct inet_peer *peer; 761da177e4SLinus Torvalds }; 771da177e4SLinus Torvalds 787eb95156SPavel Emelyanov static struct inet_frags ip4_frags; 791da177e4SLinus Torvalds 80e5a2bb84SPavel Emelyanov int ip_frag_nqueues(struct net *net) 817eb95156SPavel Emelyanov { 82e5a2bb84SPavel Emelyanov return net->ipv4.frags.nqueues; 837eb95156SPavel Emelyanov } 841da177e4SLinus Torvalds 856ddc0822SPavel Emelyanov int ip_frag_mem(struct net *net) 867eb95156SPavel Emelyanov { 876ddc0822SPavel Emelyanov return atomic_read(&net->ipv4.frags.mem); 887eb95156SPavel Emelyanov } 891da177e4SLinus Torvalds 901706d587SHerbert Xu static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, 911706d587SHerbert Xu struct net_device *dev); 921706d587SHerbert Xu 93c6fda282SPavel Emelyanov struct ip4_create_arg { 94c6fda282SPavel Emelyanov struct iphdr *iph; 95c6fda282SPavel Emelyanov u32 user; 96c6fda282SPavel Emelyanov }; 97c6fda282SPavel Emelyanov 9818277770SAl Viro static unsigned int ipqhashfn(__be16 id, __be32 saddr, __be32 daddr, u8 prot) 991da177e4SLinus Torvalds { 10018277770SAl Viro return jhash_3words((__force u32)id << 16 | prot, 10118277770SAl Viro (__force u32)saddr, (__force u32)daddr, 1027eb95156SPavel Emelyanov ip4_frags.rnd) & (INETFRAGS_HASHSZ - 1); 1031da177e4SLinus Torvalds } 1041da177e4SLinus Torvalds 105321a3a99SPavel Emelyanov static unsigned int ip4_hashfn(struct inet_frag_queue *q) 1061da177e4SLinus Torvalds { 107321a3a99SPavel Emelyanov struct ipq *ipq; 1081da177e4SLinus Torvalds 109321a3a99SPavel Emelyanov ipq = container_of(q, struct ipq, q); 110321a3a99SPavel Emelyanov return ipqhashfn(ipq->id, ipq->saddr, ipq->daddr, ipq->protocol); 1111da177e4SLinus Torvalds } 1121da177e4SLinus Torvalds 113abd6523dSPavel Emelyanov static int ip4_frag_match(struct inet_frag_queue *q, void *a) 114abd6523dSPavel Emelyanov { 115abd6523dSPavel Emelyanov struct ipq *qp; 116abd6523dSPavel Emelyanov struct ip4_create_arg *arg = a; 117abd6523dSPavel Emelyanov 118abd6523dSPavel Emelyanov qp = container_of(q, struct ipq, q); 119abd6523dSPavel Emelyanov return (qp->id == arg->iph->id && 120abd6523dSPavel Emelyanov qp->saddr == arg->iph->saddr && 121abd6523dSPavel Emelyanov qp->daddr == arg->iph->daddr && 122abd6523dSPavel Emelyanov qp->protocol == arg->iph->protocol && 123abd6523dSPavel Emelyanov qp->user == arg->user); 124abd6523dSPavel Emelyanov } 125abd6523dSPavel Emelyanov 1261da177e4SLinus Torvalds /* Memory Tracking Functions. */ 1276ddc0822SPavel Emelyanov static __inline__ void frag_kfree_skb(struct netns_frags *nf, 1286ddc0822SPavel Emelyanov struct sk_buff *skb, int *work) 1291da177e4SLinus Torvalds { 1301da177e4SLinus Torvalds if (work) 1311da177e4SLinus Torvalds *work -= skb->truesize; 1326ddc0822SPavel Emelyanov atomic_sub(skb->truesize, &nf->mem); 1331da177e4SLinus Torvalds kfree_skb(skb); 1341da177e4SLinus Torvalds } 1351da177e4SLinus Torvalds 136c6fda282SPavel Emelyanov static void ip4_frag_init(struct inet_frag_queue *q, void *a) 137c6fda282SPavel Emelyanov { 138c6fda282SPavel Emelyanov struct ipq *qp = container_of(q, struct ipq, q); 139c6fda282SPavel Emelyanov struct ip4_create_arg *arg = a; 140c6fda282SPavel Emelyanov 141c6fda282SPavel Emelyanov qp->protocol = arg->iph->protocol; 142c6fda282SPavel Emelyanov qp->id = arg->iph->id; 143c6fda282SPavel Emelyanov qp->saddr = arg->iph->saddr; 144c6fda282SPavel Emelyanov qp->daddr = arg->iph->daddr; 145c6fda282SPavel Emelyanov qp->user = arg->user; 146c6fda282SPavel Emelyanov qp->peer = sysctl_ipfrag_max_dist ? 147c6fda282SPavel Emelyanov inet_getpeer(arg->iph->saddr, 1) : NULL; 148c6fda282SPavel Emelyanov } 149c6fda282SPavel Emelyanov 1501e4b8287SPavel Emelyanov static __inline__ void ip4_frag_free(struct inet_frag_queue *q) 1511da177e4SLinus Torvalds { 1521e4b8287SPavel Emelyanov struct ipq *qp; 1531e4b8287SPavel Emelyanov 1541e4b8287SPavel Emelyanov qp = container_of(q, struct ipq, q); 1551e4b8287SPavel Emelyanov if (qp->peer) 1561e4b8287SPavel Emelyanov inet_putpeer(qp->peer); 1571da177e4SLinus Torvalds } 1581da177e4SLinus Torvalds 1591da177e4SLinus Torvalds 1601da177e4SLinus Torvalds /* Destruction primitives. */ 1611da177e4SLinus Torvalds 1624b6cb5d8SPavel Emelyanov static __inline__ void ipq_put(struct ipq *ipq) 1631da177e4SLinus Torvalds { 164762cc408SPavel Emelyanov inet_frag_put(&ipq->q, &ip4_frags); 1651da177e4SLinus Torvalds } 1661da177e4SLinus Torvalds 1671da177e4SLinus Torvalds /* Kill ipq entry. It is not destroyed immediately, 1681da177e4SLinus Torvalds * because caller (and someone more) holds reference count. 1691da177e4SLinus Torvalds */ 1701da177e4SLinus Torvalds static void ipq_kill(struct ipq *ipq) 1711da177e4SLinus Torvalds { 172277e650dSPavel Emelyanov inet_frag_kill(&ipq->q, &ip4_frags); 1731da177e4SLinus Torvalds } 1741da177e4SLinus Torvalds 1751da177e4SLinus Torvalds /* Memory limiting on fragments. Evictor trashes the oldest 1761da177e4SLinus Torvalds * fragment queue until we are back under the threshold. 1771da177e4SLinus Torvalds */ 1786ddc0822SPavel Emelyanov static void ip_evictor(struct net *net) 1791da177e4SLinus Torvalds { 1808e7999c4SPavel Emelyanov int evicted; 1811da177e4SLinus Torvalds 1826ddc0822SPavel Emelyanov evicted = inet_frag_evictor(&net->ipv4.frags, &ip4_frags); 1838e7999c4SPavel Emelyanov if (evicted) 184c5346fe3SPavel Emelyanov IP_ADD_STATS_BH(net, IPSTATS_MIB_REASMFAILS, evicted); 1851da177e4SLinus Torvalds } 1861da177e4SLinus Torvalds 1871da177e4SLinus Torvalds /* 1881da177e4SLinus Torvalds * Oops, a fragment queue timed out. Kill it and send an ICMP reply. 1891da177e4SLinus Torvalds */ 1901da177e4SLinus Torvalds static void ip_expire(unsigned long arg) 1911da177e4SLinus Torvalds { 192e521db9dSPavel Emelyanov struct ipq *qp; 19384a3aa00SPavel Emelyanov struct net *net; 194e521db9dSPavel Emelyanov 195e521db9dSPavel Emelyanov qp = container_of((struct inet_frag_queue *) arg, struct ipq, q); 19684a3aa00SPavel Emelyanov net = container_of(qp->q.net, struct net, ipv4.frags); 1971da177e4SLinus Torvalds 1985ab11c98SPavel Emelyanov spin_lock(&qp->q.lock); 1991da177e4SLinus Torvalds 200bc578a54SJoe Perches if (qp->q.last_in & INET_FRAG_COMPLETE) 2011da177e4SLinus Torvalds goto out; 2021da177e4SLinus Torvalds 2031da177e4SLinus Torvalds ipq_kill(qp); 2041da177e4SLinus Torvalds 2057c73a6faSPavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMTIMEOUT); 2067c73a6faSPavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 2071da177e4SLinus Torvalds 208bc578a54SJoe Perches if ((qp->q.last_in & INET_FRAG_FIRST_IN) && qp->q.fragments != NULL) { 2095ab11c98SPavel Emelyanov struct sk_buff *head = qp->q.fragments; 210cb84663eSDenis V. Lunev 21169df9d59SEric Dumazet rcu_read_lock(); 21269df9d59SEric Dumazet head->dev = dev_get_by_index_rcu(net, qp->iif); 213e9017b55SShan Wei if (!head->dev) 214e9017b55SShan Wei goto out_rcu_unlock; 215e9017b55SShan Wei 216e9017b55SShan Wei /* 217e9017b55SShan Wei * Only search router table for the head fragment, 218e9017b55SShan Wei * when defraging timeout at PRE_ROUTING HOOK. 219e9017b55SShan Wei */ 220e9017b55SShan Wei if (qp->user == IP_DEFRAG_CONNTRACK_IN && !skb_dst(head)) { 221e9017b55SShan Wei const struct iphdr *iph = ip_hdr(head); 222e9017b55SShan Wei int err = ip_route_input(head, iph->daddr, iph->saddr, 223e9017b55SShan Wei iph->tos, head->dev); 224e9017b55SShan Wei if (unlikely(err)) 225e9017b55SShan Wei goto out_rcu_unlock; 226e9017b55SShan Wei 227e9017b55SShan Wei /* 228e9017b55SShan Wei * Only an end host needs to send an ICMP 229e9017b55SShan Wei * "Fragment Reassembly Timeout" message, per RFC792. 230e9017b55SShan Wei */ 231e9017b55SShan Wei if (skb_rtable(head)->rt_type != RTN_LOCAL) 232e9017b55SShan Wei goto out_rcu_unlock; 233e9017b55SShan Wei 2341da177e4SLinus Torvalds } 235e9017b55SShan Wei 236e9017b55SShan Wei /* Send an ICMP "Fragment Reassembly Timeout" message. */ 237e9017b55SShan Wei icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0); 238e9017b55SShan Wei out_rcu_unlock: 239e9017b55SShan Wei rcu_read_unlock(); 240d1c9ae6dSPatrick McHardy } 2411da177e4SLinus Torvalds out: 2425ab11c98SPavel Emelyanov spin_unlock(&qp->q.lock); 2434b6cb5d8SPavel Emelyanov ipq_put(qp); 2441da177e4SLinus Torvalds } 2451da177e4SLinus Torvalds 246abd6523dSPavel Emelyanov /* Find the correct entry in the "incomplete datagrams" queue for 247abd6523dSPavel Emelyanov * this IP datagram, and create new one, if nothing is found. 248abd6523dSPavel Emelyanov */ 249ac18e750SPavel Emelyanov static inline struct ipq *ip_find(struct net *net, struct iphdr *iph, u32 user) 2501da177e4SLinus Torvalds { 251c6fda282SPavel Emelyanov struct inet_frag_queue *q; 252c6fda282SPavel Emelyanov struct ip4_create_arg arg; 253abd6523dSPavel Emelyanov unsigned int hash; 2541da177e4SLinus Torvalds 255c6fda282SPavel Emelyanov arg.iph = iph; 256c6fda282SPavel Emelyanov arg.user = user; 2579a375803SPavel Emelyanov 2589a375803SPavel Emelyanov read_lock(&ip4_frags.lock); 259abd6523dSPavel Emelyanov hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol); 260c6fda282SPavel Emelyanov 261ac18e750SPavel Emelyanov q = inet_frag_find(&net->ipv4.frags, &ip4_frags, &arg, hash); 262c6fda282SPavel Emelyanov if (q == NULL) 2631da177e4SLinus Torvalds goto out_nomem; 2641da177e4SLinus Torvalds 265c6fda282SPavel Emelyanov return container_of(q, struct ipq, q); 2661da177e4SLinus Torvalds 2671da177e4SLinus Torvalds out_nomem: 26864ce2073SPatrick McHardy LIMIT_NETDEBUG(KERN_ERR "ip_frag_create: no memory left !\n"); 2691da177e4SLinus Torvalds return NULL; 2701da177e4SLinus Torvalds } 2711da177e4SLinus Torvalds 27289cee8b1SHerbert Xu /* Is the fragment too far ahead to be part of ipq? */ 27389cee8b1SHerbert Xu static inline int ip_frag_too_far(struct ipq *qp) 27489cee8b1SHerbert Xu { 27589cee8b1SHerbert Xu struct inet_peer *peer = qp->peer; 27689cee8b1SHerbert Xu unsigned int max = sysctl_ipfrag_max_dist; 27789cee8b1SHerbert Xu unsigned int start, end; 27889cee8b1SHerbert Xu 27989cee8b1SHerbert Xu int rc; 28089cee8b1SHerbert Xu 28189cee8b1SHerbert Xu if (!peer || !max) 28289cee8b1SHerbert Xu return 0; 28389cee8b1SHerbert Xu 28489cee8b1SHerbert Xu start = qp->rid; 28589cee8b1SHerbert Xu end = atomic_inc_return(&peer->rid); 28689cee8b1SHerbert Xu qp->rid = end; 28789cee8b1SHerbert Xu 2885ab11c98SPavel Emelyanov rc = qp->q.fragments && (end - start) > max; 28989cee8b1SHerbert Xu 29089cee8b1SHerbert Xu if (rc) { 2917c73a6faSPavel Emelyanov struct net *net; 2927c73a6faSPavel Emelyanov 2937c73a6faSPavel Emelyanov net = container_of(qp->q.net, struct net, ipv4.frags); 2947c73a6faSPavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 29589cee8b1SHerbert Xu } 29689cee8b1SHerbert Xu 29789cee8b1SHerbert Xu return rc; 29889cee8b1SHerbert Xu } 29989cee8b1SHerbert Xu 30089cee8b1SHerbert Xu static int ip_frag_reinit(struct ipq *qp) 30189cee8b1SHerbert Xu { 30289cee8b1SHerbert Xu struct sk_buff *fp; 30389cee8b1SHerbert Xu 304b2fd5321SPavel Emelyanov if (!mod_timer(&qp->q.timer, jiffies + qp->q.net->timeout)) { 3055ab11c98SPavel Emelyanov atomic_inc(&qp->q.refcnt); 30689cee8b1SHerbert Xu return -ETIMEDOUT; 30789cee8b1SHerbert Xu } 30889cee8b1SHerbert Xu 3095ab11c98SPavel Emelyanov fp = qp->q.fragments; 31089cee8b1SHerbert Xu do { 31189cee8b1SHerbert Xu struct sk_buff *xp = fp->next; 3126ddc0822SPavel Emelyanov frag_kfree_skb(qp->q.net, fp, NULL); 31389cee8b1SHerbert Xu fp = xp; 31489cee8b1SHerbert Xu } while (fp); 31589cee8b1SHerbert Xu 3165ab11c98SPavel Emelyanov qp->q.last_in = 0; 3175ab11c98SPavel Emelyanov qp->q.len = 0; 3185ab11c98SPavel Emelyanov qp->q.meat = 0; 3195ab11c98SPavel Emelyanov qp->q.fragments = NULL; 32089cee8b1SHerbert Xu qp->iif = 0; 32189cee8b1SHerbert Xu 32289cee8b1SHerbert Xu return 0; 32389cee8b1SHerbert Xu } 32489cee8b1SHerbert Xu 3251da177e4SLinus Torvalds /* Add new segment to existing queue. */ 3261706d587SHerbert Xu static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb) 3271da177e4SLinus Torvalds { 3281da177e4SLinus Torvalds struct sk_buff *prev, *next; 3291706d587SHerbert Xu struct net_device *dev; 3301da177e4SLinus Torvalds int flags, offset; 3311da177e4SLinus Torvalds int ihl, end; 3321706d587SHerbert Xu int err = -ENOENT; 3331da177e4SLinus Torvalds 334bc578a54SJoe Perches if (qp->q.last_in & INET_FRAG_COMPLETE) 3351da177e4SLinus Torvalds goto err; 3361da177e4SLinus Torvalds 33789cee8b1SHerbert Xu if (!(IPCB(skb)->flags & IPSKB_FRAG_COMPLETE) && 3381706d587SHerbert Xu unlikely(ip_frag_too_far(qp)) && 3391706d587SHerbert Xu unlikely(err = ip_frag_reinit(qp))) { 34089cee8b1SHerbert Xu ipq_kill(qp); 34189cee8b1SHerbert Xu goto err; 34289cee8b1SHerbert Xu } 34389cee8b1SHerbert Xu 344eddc9ec5SArnaldo Carvalho de Melo offset = ntohs(ip_hdr(skb)->frag_off); 3451da177e4SLinus Torvalds flags = offset & ~IP_OFFSET; 3461da177e4SLinus Torvalds offset &= IP_OFFSET; 3471da177e4SLinus Torvalds offset <<= 3; /* offset is in 8-byte chunks */ 348c9bdd4b5SArnaldo Carvalho de Melo ihl = ip_hdrlen(skb); 3491da177e4SLinus Torvalds 3501da177e4SLinus Torvalds /* Determine the position of this fragment. */ 3511da177e4SLinus Torvalds end = offset + skb->len - ihl; 3521706d587SHerbert Xu err = -EINVAL; 3531da177e4SLinus Torvalds 3541da177e4SLinus Torvalds /* Is this the final fragment? */ 3551da177e4SLinus Torvalds if ((flags & IP_MF) == 0) { 3561da177e4SLinus Torvalds /* If we already have some bits beyond end 3571da177e4SLinus Torvalds * or have different end, the segment is corrrupted. 3581da177e4SLinus Torvalds */ 3595ab11c98SPavel Emelyanov if (end < qp->q.len || 360bc578a54SJoe Perches ((qp->q.last_in & INET_FRAG_LAST_IN) && end != qp->q.len)) 3611da177e4SLinus Torvalds goto err; 362bc578a54SJoe Perches qp->q.last_in |= INET_FRAG_LAST_IN; 3635ab11c98SPavel Emelyanov qp->q.len = end; 3641da177e4SLinus Torvalds } else { 3651da177e4SLinus Torvalds if (end&7) { 3661da177e4SLinus Torvalds end &= ~7; 3671da177e4SLinus Torvalds if (skb->ip_summed != CHECKSUM_UNNECESSARY) 3681da177e4SLinus Torvalds skb->ip_summed = CHECKSUM_NONE; 3691da177e4SLinus Torvalds } 3705ab11c98SPavel Emelyanov if (end > qp->q.len) { 3711da177e4SLinus Torvalds /* Some bits beyond end -> corruption. */ 372bc578a54SJoe Perches if (qp->q.last_in & INET_FRAG_LAST_IN) 3731da177e4SLinus Torvalds goto err; 3745ab11c98SPavel Emelyanov qp->q.len = end; 3751da177e4SLinus Torvalds } 3761da177e4SLinus Torvalds } 3771da177e4SLinus Torvalds if (end == offset) 3781da177e4SLinus Torvalds goto err; 3791da177e4SLinus Torvalds 3801706d587SHerbert Xu err = -ENOMEM; 3811da177e4SLinus Torvalds if (pskb_pull(skb, ihl) == NULL) 3821da177e4SLinus Torvalds goto err; 3831706d587SHerbert Xu 3841706d587SHerbert Xu err = pskb_trim_rcsum(skb, end - offset); 3851706d587SHerbert Xu if (err) 3861da177e4SLinus Torvalds goto err; 3871da177e4SLinus Torvalds 3881da177e4SLinus Torvalds /* Find out which fragments are in front and at the back of us 3891da177e4SLinus Torvalds * in the chain of fragments so far. We must know where to put 3901da177e4SLinus Torvalds * this fragment, right? 3911da177e4SLinus Torvalds */ 3921da177e4SLinus Torvalds prev = NULL; 3935ab11c98SPavel Emelyanov for (next = qp->q.fragments; next != NULL; next = next->next) { 3941da177e4SLinus Torvalds if (FRAG_CB(next)->offset >= offset) 3951da177e4SLinus Torvalds break; /* bingo! */ 3961da177e4SLinus Torvalds prev = next; 3971da177e4SLinus Torvalds } 3981da177e4SLinus Torvalds 3991da177e4SLinus Torvalds /* We found where to put this one. Check for overlap with 4001da177e4SLinus Torvalds * preceding fragment, and, if needed, align things so that 4011da177e4SLinus Torvalds * any overlaps are eliminated. 4021da177e4SLinus Torvalds */ 4031da177e4SLinus Torvalds if (prev) { 4041da177e4SLinus Torvalds int i = (FRAG_CB(prev)->offset + prev->len) - offset; 4051da177e4SLinus Torvalds 4061da177e4SLinus Torvalds if (i > 0) { 4071da177e4SLinus Torvalds offset += i; 4081706d587SHerbert Xu err = -EINVAL; 4091da177e4SLinus Torvalds if (end <= offset) 4101da177e4SLinus Torvalds goto err; 4111706d587SHerbert Xu err = -ENOMEM; 4121da177e4SLinus Torvalds if (!pskb_pull(skb, i)) 4131da177e4SLinus Torvalds goto err; 4141da177e4SLinus Torvalds if (skb->ip_summed != CHECKSUM_UNNECESSARY) 4151da177e4SLinus Torvalds skb->ip_summed = CHECKSUM_NONE; 4161da177e4SLinus Torvalds } 4171da177e4SLinus Torvalds } 4181da177e4SLinus Torvalds 4191706d587SHerbert Xu err = -ENOMEM; 4201706d587SHerbert Xu 4211da177e4SLinus Torvalds while (next && FRAG_CB(next)->offset < end) { 4221da177e4SLinus Torvalds int i = end - FRAG_CB(next)->offset; /* overlap is 'i' bytes */ 4231da177e4SLinus Torvalds 4241da177e4SLinus Torvalds if (i < next->len) { 4251da177e4SLinus Torvalds /* Eat head of the next overlapped fragment 4261da177e4SLinus Torvalds * and leave the loop. The next ones cannot overlap. 4271da177e4SLinus Torvalds */ 4281da177e4SLinus Torvalds if (!pskb_pull(next, i)) 4291da177e4SLinus Torvalds goto err; 4301da177e4SLinus Torvalds FRAG_CB(next)->offset += i; 4315ab11c98SPavel Emelyanov qp->q.meat -= i; 4321da177e4SLinus Torvalds if (next->ip_summed != CHECKSUM_UNNECESSARY) 4331da177e4SLinus Torvalds next->ip_summed = CHECKSUM_NONE; 4341da177e4SLinus Torvalds break; 4351da177e4SLinus Torvalds } else { 4361da177e4SLinus Torvalds struct sk_buff *free_it = next; 4371da177e4SLinus Torvalds 43847c6bf77SPeter Zijlstra /* Old fragment is completely overridden with 4391da177e4SLinus Torvalds * new one drop it. 4401da177e4SLinus Torvalds */ 4411da177e4SLinus Torvalds next = next->next; 4421da177e4SLinus Torvalds 4431da177e4SLinus Torvalds if (prev) 4441da177e4SLinus Torvalds prev->next = next; 4451da177e4SLinus Torvalds else 4465ab11c98SPavel Emelyanov qp->q.fragments = next; 4471da177e4SLinus Torvalds 4485ab11c98SPavel Emelyanov qp->q.meat -= free_it->len; 4496ddc0822SPavel Emelyanov frag_kfree_skb(qp->q.net, free_it, NULL); 4501da177e4SLinus Torvalds } 4511da177e4SLinus Torvalds } 4521da177e4SLinus Torvalds 4531da177e4SLinus Torvalds FRAG_CB(skb)->offset = offset; 4541da177e4SLinus Torvalds 4551da177e4SLinus Torvalds /* Insert this fragment in the chain of fragments. */ 4561da177e4SLinus Torvalds skb->next = next; 4571da177e4SLinus Torvalds if (prev) 4581da177e4SLinus Torvalds prev->next = skb; 4591da177e4SLinus Torvalds else 4605ab11c98SPavel Emelyanov qp->q.fragments = skb; 4611da177e4SLinus Torvalds 4621706d587SHerbert Xu dev = skb->dev; 4631706d587SHerbert Xu if (dev) { 4641706d587SHerbert Xu qp->iif = dev->ifindex; 4651da177e4SLinus Torvalds skb->dev = NULL; 4661706d587SHerbert Xu } 4675ab11c98SPavel Emelyanov qp->q.stamp = skb->tstamp; 4685ab11c98SPavel Emelyanov qp->q.meat += skb->len; 4696ddc0822SPavel Emelyanov atomic_add(skb->truesize, &qp->q.net->mem); 4701da177e4SLinus Torvalds if (offset == 0) 471bc578a54SJoe Perches qp->q.last_in |= INET_FRAG_FIRST_IN; 4721da177e4SLinus Torvalds 473bc578a54SJoe Perches if (qp->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && 474bc578a54SJoe Perches qp->q.meat == qp->q.len) 4751706d587SHerbert Xu return ip_frag_reasm(qp, prev, dev); 4761706d587SHerbert Xu 4777eb95156SPavel Emelyanov write_lock(&ip4_frags.lock); 4783140c25cSPavel Emelyanov list_move_tail(&qp->q.lru_list, &qp->q.net->lru_list); 4797eb95156SPavel Emelyanov write_unlock(&ip4_frags.lock); 4801706d587SHerbert Xu return -EINPROGRESS; 4811da177e4SLinus Torvalds 4821da177e4SLinus Torvalds err: 4831da177e4SLinus Torvalds kfree_skb(skb); 4841706d587SHerbert Xu return err; 4851da177e4SLinus Torvalds } 4861da177e4SLinus Torvalds 4871da177e4SLinus Torvalds 4881da177e4SLinus Torvalds /* Build a new IP datagram from all its fragments. */ 4891da177e4SLinus Torvalds 4901706d587SHerbert Xu static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, 4911706d587SHerbert Xu struct net_device *dev) 4921da177e4SLinus Torvalds { 4932bad35b7SJorge Boncompte [DTI2] struct net *net = container_of(qp->q.net, struct net, ipv4.frags); 4941da177e4SLinus Torvalds struct iphdr *iph; 4955ab11c98SPavel Emelyanov struct sk_buff *fp, *head = qp->q.fragments; 4961da177e4SLinus Torvalds int len; 4971da177e4SLinus Torvalds int ihlen; 4981706d587SHerbert Xu int err; 4991da177e4SLinus Torvalds 5001da177e4SLinus Torvalds ipq_kill(qp); 5011da177e4SLinus Torvalds 5021706d587SHerbert Xu /* Make the one we just received the head. */ 5031706d587SHerbert Xu if (prev) { 5041706d587SHerbert Xu head = prev->next; 5051706d587SHerbert Xu fp = skb_clone(head, GFP_ATOMIC); 5061706d587SHerbert Xu if (!fp) 5071706d587SHerbert Xu goto out_nomem; 5081706d587SHerbert Xu 5091706d587SHerbert Xu fp->next = head->next; 5101706d587SHerbert Xu prev->next = fp; 5111706d587SHerbert Xu 5125ab11c98SPavel Emelyanov skb_morph(head, qp->q.fragments); 5135ab11c98SPavel Emelyanov head->next = qp->q.fragments->next; 5141706d587SHerbert Xu 5155ab11c98SPavel Emelyanov kfree_skb(qp->q.fragments); 5165ab11c98SPavel Emelyanov qp->q.fragments = head; 5171706d587SHerbert Xu } 5181706d587SHerbert Xu 519547b792cSIlpo Järvinen WARN_ON(head == NULL); 520547b792cSIlpo Järvinen WARN_ON(FRAG_CB(head)->offset != 0); 5211da177e4SLinus Torvalds 5221da177e4SLinus Torvalds /* Allocate a new buffer for the datagram. */ 523c9bdd4b5SArnaldo Carvalho de Melo ihlen = ip_hdrlen(head); 5245ab11c98SPavel Emelyanov len = ihlen + qp->q.len; 5251da177e4SLinus Torvalds 5261706d587SHerbert Xu err = -E2BIG; 5271da177e4SLinus Torvalds if (len > 65535) 5281da177e4SLinus Torvalds goto out_oversize; 5291da177e4SLinus Torvalds 5301da177e4SLinus Torvalds /* Head of list must not be cloned. */ 5311da177e4SLinus Torvalds if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) 5321da177e4SLinus Torvalds goto out_nomem; 5331da177e4SLinus Torvalds 5341da177e4SLinus Torvalds /* If the first fragment is fragmented itself, we split 5351da177e4SLinus Torvalds * it to two chunks: the first with data and paged part 5361da177e4SLinus Torvalds * and the second, holding only fragments. */ 537d7fcf1a5SDavid S. Miller if (skb_has_frags(head)) { 5381da177e4SLinus Torvalds struct sk_buff *clone; 5391da177e4SLinus Torvalds int i, plen = 0; 5401da177e4SLinus Torvalds 5411da177e4SLinus Torvalds if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) 5421da177e4SLinus Torvalds goto out_nomem; 5431da177e4SLinus Torvalds clone->next = head->next; 5441da177e4SLinus Torvalds head->next = clone; 5451da177e4SLinus Torvalds skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; 546d7fcf1a5SDavid S. Miller skb_frag_list_init(head); 5471da177e4SLinus Torvalds for (i=0; i<skb_shinfo(head)->nr_frags; i++) 5481da177e4SLinus Torvalds plen += skb_shinfo(head)->frags[i].size; 5491da177e4SLinus Torvalds clone->len = clone->data_len = head->data_len - plen; 5501da177e4SLinus Torvalds head->data_len -= clone->len; 5511da177e4SLinus Torvalds head->len -= clone->len; 5521da177e4SLinus Torvalds clone->csum = 0; 5531da177e4SLinus Torvalds clone->ip_summed = head->ip_summed; 5546ddc0822SPavel Emelyanov atomic_add(clone->truesize, &qp->q.net->mem); 5551da177e4SLinus Torvalds } 5561da177e4SLinus Torvalds 5571da177e4SLinus Torvalds skb_shinfo(head)->frag_list = head->next; 558d56f90a7SArnaldo Carvalho de Melo skb_push(head, head->data - skb_network_header(head)); 5591da177e4SLinus Torvalds 5601da177e4SLinus Torvalds for (fp=head->next; fp; fp = fp->next) { 5611da177e4SLinus Torvalds head->data_len += fp->len; 5621da177e4SLinus Torvalds head->len += fp->len; 5631da177e4SLinus Torvalds if (head->ip_summed != fp->ip_summed) 5641da177e4SLinus Torvalds head->ip_summed = CHECKSUM_NONE; 56584fa7933SPatrick McHardy else if (head->ip_summed == CHECKSUM_COMPLETE) 5661da177e4SLinus Torvalds head->csum = csum_add(head->csum, fp->csum); 5671da177e4SLinus Torvalds head->truesize += fp->truesize; 5681da177e4SLinus Torvalds } 569d27f9b35SEric Dumazet atomic_sub(head->truesize, &qp->q.net->mem); 5701da177e4SLinus Torvalds 5711da177e4SLinus Torvalds head->next = NULL; 5721da177e4SLinus Torvalds head->dev = dev; 5735ab11c98SPavel Emelyanov head->tstamp = qp->q.stamp; 5741da177e4SLinus Torvalds 575eddc9ec5SArnaldo Carvalho de Melo iph = ip_hdr(head); 5761da177e4SLinus Torvalds iph->frag_off = 0; 5771da177e4SLinus Torvalds iph->tot_len = htons(len); 5782bad35b7SJorge Boncompte [DTI2] IP_INC_STATS_BH(net, IPSTATS_MIB_REASMOKS); 5795ab11c98SPavel Emelyanov qp->q.fragments = NULL; 5801706d587SHerbert Xu return 0; 5811da177e4SLinus Torvalds 5821da177e4SLinus Torvalds out_nomem: 58364ce2073SPatrick McHardy LIMIT_NETDEBUG(KERN_ERR "IP: queue_glue: no memory for gluing " 58464ce2073SPatrick McHardy "queue %p\n", qp); 58545542479SDavid Howells err = -ENOMEM; 5861da177e4SLinus Torvalds goto out_fail; 5871da177e4SLinus Torvalds out_oversize: 5881da177e4SLinus Torvalds if (net_ratelimit()) 589673d57e7SHarvey Harrison printk(KERN_INFO "Oversized IP packet from %pI4.\n", 590673d57e7SHarvey Harrison &qp->saddr); 5911da177e4SLinus Torvalds out_fail: 592bbf31bf1SDavid Ford IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 5931706d587SHerbert Xu return err; 5941da177e4SLinus Torvalds } 5951da177e4SLinus Torvalds 5961da177e4SLinus Torvalds /* Process an incoming IP datagram fragment. */ 597776c729eSHerbert Xu int ip_defrag(struct sk_buff *skb, u32 user) 5981da177e4SLinus Torvalds { 5991da177e4SLinus Torvalds struct ipq *qp; 600ac18e750SPavel Emelyanov struct net *net; 6011da177e4SLinus Torvalds 602adf30907SEric Dumazet net = skb->dev ? dev_net(skb->dev) : dev_net(skb_dst(skb)->dev); 6037c73a6faSPavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMREQDS); 6041da177e4SLinus Torvalds 6051da177e4SLinus Torvalds /* Start by cleaning up the memory. */ 606e31e0bdcSPavel Emelyanov if (atomic_read(&net->ipv4.frags.mem) > net->ipv4.frags.high_thresh) 6076ddc0822SPavel Emelyanov ip_evictor(net); 6081da177e4SLinus Torvalds 6091da177e4SLinus Torvalds /* Lookup (or create) queue header */ 610ac18e750SPavel Emelyanov if ((qp = ip_find(net, ip_hdr(skb), user)) != NULL) { 6111706d587SHerbert Xu int ret; 6121da177e4SLinus Torvalds 6135ab11c98SPavel Emelyanov spin_lock(&qp->q.lock); 6141da177e4SLinus Torvalds 6151706d587SHerbert Xu ret = ip_frag_queue(qp, skb); 6161da177e4SLinus Torvalds 6175ab11c98SPavel Emelyanov spin_unlock(&qp->q.lock); 6184b6cb5d8SPavel Emelyanov ipq_put(qp); 619776c729eSHerbert Xu return ret; 6201da177e4SLinus Torvalds } 6211da177e4SLinus Torvalds 6227c73a6faSPavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 6231da177e4SLinus Torvalds kfree_skb(skb); 624776c729eSHerbert Xu return -ENOMEM; 6251da177e4SLinus Torvalds } 6261da177e4SLinus Torvalds 6278d8354d2SPavel Emelyanov #ifdef CONFIG_SYSCTL 6288d8354d2SPavel Emelyanov static int zero; 6298d8354d2SPavel Emelyanov 6300a64b4b8SPavel Emelyanov static struct ctl_table ip4_frags_ns_ctl_table[] = { 6318d8354d2SPavel Emelyanov { 6328d8354d2SPavel Emelyanov .procname = "ipfrag_high_thresh", 633e31e0bdcSPavel Emelyanov .data = &init_net.ipv4.frags.high_thresh, 6348d8354d2SPavel Emelyanov .maxlen = sizeof(int), 6358d8354d2SPavel Emelyanov .mode = 0644, 6366d9f239aSAlexey Dobriyan .proc_handler = proc_dointvec 6378d8354d2SPavel Emelyanov }, 6388d8354d2SPavel Emelyanov { 6398d8354d2SPavel Emelyanov .procname = "ipfrag_low_thresh", 640e31e0bdcSPavel Emelyanov .data = &init_net.ipv4.frags.low_thresh, 6418d8354d2SPavel Emelyanov .maxlen = sizeof(int), 6428d8354d2SPavel Emelyanov .mode = 0644, 6436d9f239aSAlexey Dobriyan .proc_handler = proc_dointvec 6448d8354d2SPavel Emelyanov }, 6458d8354d2SPavel Emelyanov { 6468d8354d2SPavel Emelyanov .procname = "ipfrag_time", 647b2fd5321SPavel Emelyanov .data = &init_net.ipv4.frags.timeout, 6488d8354d2SPavel Emelyanov .maxlen = sizeof(int), 6498d8354d2SPavel Emelyanov .mode = 0644, 6506d9f239aSAlexey Dobriyan .proc_handler = proc_dointvec_jiffies, 6518d8354d2SPavel Emelyanov }, 6527d291ebbSPavel Emelyanov { } 6537d291ebbSPavel Emelyanov }; 6547d291ebbSPavel Emelyanov 6557d291ebbSPavel Emelyanov static struct ctl_table ip4_frags_ctl_table[] = { 6568d8354d2SPavel Emelyanov { 6578d8354d2SPavel Emelyanov .procname = "ipfrag_secret_interval", 6583b4bc4a2SPavel Emelyanov .data = &ip4_frags.secret_interval, 6598d8354d2SPavel Emelyanov .maxlen = sizeof(int), 6608d8354d2SPavel Emelyanov .mode = 0644, 6616d9f239aSAlexey Dobriyan .proc_handler = proc_dointvec_jiffies, 6628d8354d2SPavel Emelyanov }, 6638d8354d2SPavel Emelyanov { 6648d8354d2SPavel Emelyanov .procname = "ipfrag_max_dist", 6658d8354d2SPavel Emelyanov .data = &sysctl_ipfrag_max_dist, 6668d8354d2SPavel Emelyanov .maxlen = sizeof(int), 6678d8354d2SPavel Emelyanov .mode = 0644, 6686d9f239aSAlexey Dobriyan .proc_handler = proc_dointvec_minmax, 6698d8354d2SPavel Emelyanov .extra1 = &zero 6708d8354d2SPavel Emelyanov }, 6718d8354d2SPavel Emelyanov { } 6728d8354d2SPavel Emelyanov }; 6738d8354d2SPavel Emelyanov 6742c8c1e72SAlexey Dobriyan static int __net_init ip4_frags_ns_ctl_register(struct net *net) 6758d8354d2SPavel Emelyanov { 676e4a2d5c2SPavel Emelyanov struct ctl_table *table; 6778d8354d2SPavel Emelyanov struct ctl_table_header *hdr; 6788d8354d2SPavel Emelyanov 6790a64b4b8SPavel Emelyanov table = ip4_frags_ns_ctl_table; 68009ad9bc7SOctavian Purdila if (!net_eq(net, &init_net)) { 6810a64b4b8SPavel Emelyanov table = kmemdup(table, sizeof(ip4_frags_ns_ctl_table), GFP_KERNEL); 682e4a2d5c2SPavel Emelyanov if (table == NULL) 683e4a2d5c2SPavel Emelyanov goto err_alloc; 684e4a2d5c2SPavel Emelyanov 685e31e0bdcSPavel Emelyanov table[0].data = &net->ipv4.frags.high_thresh; 686e31e0bdcSPavel Emelyanov table[1].data = &net->ipv4.frags.low_thresh; 687b2fd5321SPavel Emelyanov table[2].data = &net->ipv4.frags.timeout; 688e4a2d5c2SPavel Emelyanov } 689e4a2d5c2SPavel Emelyanov 690e4a2d5c2SPavel Emelyanov hdr = register_net_sysctl_table(net, net_ipv4_ctl_path, table); 691e4a2d5c2SPavel Emelyanov if (hdr == NULL) 692e4a2d5c2SPavel Emelyanov goto err_reg; 693e4a2d5c2SPavel Emelyanov 694e4a2d5c2SPavel Emelyanov net->ipv4.frags_hdr = hdr; 695e4a2d5c2SPavel Emelyanov return 0; 696e4a2d5c2SPavel Emelyanov 697e4a2d5c2SPavel Emelyanov err_reg: 69809ad9bc7SOctavian Purdila if (!net_eq(net, &init_net)) 699e4a2d5c2SPavel Emelyanov kfree(table); 700e4a2d5c2SPavel Emelyanov err_alloc: 701e4a2d5c2SPavel Emelyanov return -ENOMEM; 702e4a2d5c2SPavel Emelyanov } 703e4a2d5c2SPavel Emelyanov 7042c8c1e72SAlexey Dobriyan static void __net_exit ip4_frags_ns_ctl_unregister(struct net *net) 705e4a2d5c2SPavel Emelyanov { 706e4a2d5c2SPavel Emelyanov struct ctl_table *table; 707e4a2d5c2SPavel Emelyanov 708e4a2d5c2SPavel Emelyanov table = net->ipv4.frags_hdr->ctl_table_arg; 709e4a2d5c2SPavel Emelyanov unregister_net_sysctl_table(net->ipv4.frags_hdr); 710e4a2d5c2SPavel Emelyanov kfree(table); 7118d8354d2SPavel Emelyanov } 7127d291ebbSPavel Emelyanov 7137d291ebbSPavel Emelyanov static void ip4_frags_ctl_register(void) 7147d291ebbSPavel Emelyanov { 7157d291ebbSPavel Emelyanov register_net_sysctl_rotable(net_ipv4_ctl_path, ip4_frags_ctl_table); 7167d291ebbSPavel Emelyanov } 7178d8354d2SPavel Emelyanov #else 7180a64b4b8SPavel Emelyanov static inline int ip4_frags_ns_ctl_register(struct net *net) 7198d8354d2SPavel Emelyanov { 7208d8354d2SPavel Emelyanov return 0; 7218d8354d2SPavel Emelyanov } 722e4a2d5c2SPavel Emelyanov 7230a64b4b8SPavel Emelyanov static inline void ip4_frags_ns_ctl_unregister(struct net *net) 724e4a2d5c2SPavel Emelyanov { 725e4a2d5c2SPavel Emelyanov } 7267d291ebbSPavel Emelyanov 7277d291ebbSPavel Emelyanov static inline void ip4_frags_ctl_register(void) 7287d291ebbSPavel Emelyanov { 7297d291ebbSPavel Emelyanov } 7308d8354d2SPavel Emelyanov #endif 7318d8354d2SPavel Emelyanov 7322c8c1e72SAlexey Dobriyan static int __net_init ipv4_frags_init_net(struct net *net) 7338d8354d2SPavel Emelyanov { 734b2fd5321SPavel Emelyanov /* 735e31e0bdcSPavel Emelyanov * Fragment cache limits. We will commit 256K at one time. Should we 736e31e0bdcSPavel Emelyanov * cross that limit we will prune down to 192K. This should cope with 737e31e0bdcSPavel Emelyanov * even the most extreme cases without allowing an attacker to 738e31e0bdcSPavel Emelyanov * measurably harm machine performance. 739e31e0bdcSPavel Emelyanov */ 740e31e0bdcSPavel Emelyanov net->ipv4.frags.high_thresh = 256 * 1024; 741e31e0bdcSPavel Emelyanov net->ipv4.frags.low_thresh = 192 * 1024; 742e31e0bdcSPavel Emelyanov /* 743b2fd5321SPavel Emelyanov * Important NOTE! Fragment queue must be destroyed before MSL expires. 744b2fd5321SPavel Emelyanov * RFC791 is wrong proposing to prolongate timer each fragment arrival 745b2fd5321SPavel Emelyanov * by TTL. 746b2fd5321SPavel Emelyanov */ 747b2fd5321SPavel Emelyanov net->ipv4.frags.timeout = IP_FRAG_TIME; 748b2fd5321SPavel Emelyanov 749e5a2bb84SPavel Emelyanov inet_frags_init_net(&net->ipv4.frags); 750e5a2bb84SPavel Emelyanov 7510a64b4b8SPavel Emelyanov return ip4_frags_ns_ctl_register(net); 7528d8354d2SPavel Emelyanov } 7538d8354d2SPavel Emelyanov 7542c8c1e72SAlexey Dobriyan static void __net_exit ipv4_frags_exit_net(struct net *net) 75581566e83SPavel Emelyanov { 7560a64b4b8SPavel Emelyanov ip4_frags_ns_ctl_unregister(net); 75781566e83SPavel Emelyanov inet_frags_exit_net(&net->ipv4.frags, &ip4_frags); 75881566e83SPavel Emelyanov } 75981566e83SPavel Emelyanov 76081566e83SPavel Emelyanov static struct pernet_operations ip4_frags_ops = { 76181566e83SPavel Emelyanov .init = ipv4_frags_init_net, 76281566e83SPavel Emelyanov .exit = ipv4_frags_exit_net, 76381566e83SPavel Emelyanov }; 76481566e83SPavel Emelyanov 765b7aa0bf7SEric Dumazet void __init ipfrag_init(void) 7661da177e4SLinus Torvalds { 7677d291ebbSPavel Emelyanov ip4_frags_ctl_register(); 76881566e83SPavel Emelyanov register_pernet_subsys(&ip4_frags_ops); 769321a3a99SPavel Emelyanov ip4_frags.hashfn = ip4_hashfn; 770c6fda282SPavel Emelyanov ip4_frags.constructor = ip4_frag_init; 7711e4b8287SPavel Emelyanov ip4_frags.destructor = ip4_frag_free; 7721e4b8287SPavel Emelyanov ip4_frags.skb_free = NULL; 7731e4b8287SPavel Emelyanov ip4_frags.qsize = sizeof(struct ipq); 774abd6523dSPavel Emelyanov ip4_frags.match = ip4_frag_match; 775e521db9dSPavel Emelyanov ip4_frags.frag_expire = ip_expire; 7763b4bc4a2SPavel Emelyanov ip4_frags.secret_interval = 10 * 60 * HZ; 7777eb95156SPavel Emelyanov inet_frags_init(&ip4_frags); 7781da177e4SLinus Torvalds } 7791da177e4SLinus Torvalds 7801da177e4SLinus Torvalds EXPORT_SYMBOL(ip_defrag); 781