ip_fragment.c revision d1c9ae6d1e7b95cedc8e39e8949e795379a0669e
11da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 21da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * INET An implementation of the TCP/IP protocol suite for the LINUX 31da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * operating system. INET is implemented using the BSD Socket 41da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * interface as the means of communication with the user level. 51da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 61da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * The IP fragmentation functionality. 7e905a9edab7f4f14f9213b52234e4a346c690911YOSHIFUJI Hideaki * 81da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Authors: Fred N. van Kempen <waltje@uWalt.NL.Mugnet.ORG> 9113aa838ec3a235d883f8357d31d90e16c47fc89Alan Cox * Alan Cox <alan@lxorguk.ukuu.org.uk> 101da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Fixes: 121da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Alan Cox : Split from ip.c , see ip_input.c for history. 131da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * David S. Miller : Begin massive cleanup... 141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Andi Kleen : Add sysctls. 151da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * xxxx : Overlapfrag bug. 161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Ultima : ip_expire() kernel panic. 171da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Bill Hawes : Frag accounting and evictor fixes. 181da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * John McDonald : 0 length frag bug. 191da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Alexey Kuznetsov: SMP races, threading, cleanup. 201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Patrick McHardy : LRU queue of frag heads for evictor. 211da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 221da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2389cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu#include <linux/compiler.h> 241da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/module.h> 251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/types.h> 261da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/mm.h> 271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/jiffies.h> 281da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/skbuff.h> 291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/list.h> 301da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/ip.h> 311da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/icmp.h> 321da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/netdevice.h> 331da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/jhash.h> 341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/random.h> 35e9017b55189355e9e6569990a18919e83f35bccbShan Wei#include <net/route.h> 36e9017b55189355e9e6569990a18919e83f35bccbShan Wei#include <net/dst.h> 371da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <net/sock.h> 381da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <net/ip.h> 391da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <net/icmp.h> 401da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <net/checksum.h> 4189cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu#include <net/inetpeer.h> 425ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov#include <net/inet_frag.h> 431da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/tcp.h> 441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/udp.h> 451da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/inet.h> 461da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/netfilter_ipv4.h> 471da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 481da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* NOTE. Logic of IP defragmentation is parallel to corresponding IPv6 491da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * code now. If you change something here, _PLEASE_ update ipv6/reassembly.c 501da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * as well. Or notify me, at least. --ANK 511da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 521da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 538d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanovstatic int sysctl_ipfrag_max_dist __read_mostly = 64; 5489cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 551da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstruct ipfrag_skb_cb 561da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 571da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds struct inet_skb_parm h; 581da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int offset; 591da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds}; 601da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 61fd3f8c4cb632c28ef915a535617a0fcddcfe3f80Jianjun Kong#define FRAG_CB(skb) ((struct ipfrag_skb_cb *)((skb)->cb)) 621da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 631da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* Describe an entry in the "incomplete datagrams" queue. */ 641da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstruct ipq { 655ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov struct inet_frag_queue q; 665ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov 671da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds u32 user; 68182777700d912a69824245e9ee99148ac0aa57d7Al Viro __be32 saddr; 69182777700d912a69824245e9ee99148ac0aa57d7Al Viro __be32 daddr; 70182777700d912a69824245e9ee99148ac0aa57d7Al Viro __be16 id; 711da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds u8 protocol; 7289cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu int iif; 7389cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu unsigned int rid; 7489cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu struct inet_peer *peer; 751da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds}; 761da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 777eb95156d9dce2f59794264db336ce007d71638bPavel Emelyanovstatic struct inet_frags ip4_frags; 781da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 79e5a2bb842cd9681d00d4ca963e63e4d3647e66f8Pavel Emelyanovint ip_frag_nqueues(struct net *net) 807eb95156d9dce2f59794264db336ce007d71638bPavel Emelyanov{ 81e5a2bb842cd9681d00d4ca963e63e4d3647e66f8Pavel Emelyanov return net->ipv4.frags.nqueues; 827eb95156d9dce2f59794264db336ce007d71638bPavel Emelyanov} 831da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 846ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanovint ip_frag_mem(struct net *net) 857eb95156d9dce2f59794264db336ce007d71638bPavel Emelyanov{ 866ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov return atomic_read(&net->ipv4.frags.mem); 877eb95156d9dce2f59794264db336ce007d71638bPavel Emelyanov} 881da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 891706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xustatic int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, 901706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu struct net_device *dev); 911706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu 92c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanovstruct ip4_create_arg { 93c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov struct iphdr *iph; 94c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov u32 user; 95c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov}; 96c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov 97182777700d912a69824245e9ee99148ac0aa57d7Al Virostatic unsigned int ipqhashfn(__be16 id, __be32 saddr, __be32 daddr, u8 prot) 981da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 99182777700d912a69824245e9ee99148ac0aa57d7Al Viro return jhash_3words((__force u32)id << 16 | prot, 100182777700d912a69824245e9ee99148ac0aa57d7Al Viro (__force u32)saddr, (__force u32)daddr, 1017eb95156d9dce2f59794264db336ce007d71638bPavel Emelyanov ip4_frags.rnd) & (INETFRAGS_HASHSZ - 1); 1021da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 1031da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 104321a3a99e4717b960e21c62fc6a140d21453df7fPavel Emelyanovstatic unsigned int ip4_hashfn(struct inet_frag_queue *q) 1051da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 106321a3a99e4717b960e21c62fc6a140d21453df7fPavel Emelyanov struct ipq *ipq; 1071da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 108321a3a99e4717b960e21c62fc6a140d21453df7fPavel Emelyanov ipq = container_of(q, struct ipq, q); 109321a3a99e4717b960e21c62fc6a140d21453df7fPavel Emelyanov return ipqhashfn(ipq->id, ipq->saddr, ipq->daddr, ipq->protocol); 1101da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 1111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 112abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanovstatic int ip4_frag_match(struct inet_frag_queue *q, void *a) 113abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov{ 114abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov struct ipq *qp; 115abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov struct ip4_create_arg *arg = a; 116abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov 117abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov qp = container_of(q, struct ipq, q); 118abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov return (qp->id == arg->iph->id && 119abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov qp->saddr == arg->iph->saddr && 120abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov qp->daddr == arg->iph->daddr && 121abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov qp->protocol == arg->iph->protocol && 122abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov qp->user == arg->user); 123abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov} 124abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov 1251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* Memory Tracking Functions. */ 1266ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanovstatic __inline__ void frag_kfree_skb(struct netns_frags *nf, 1276ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov struct sk_buff *skb, int *work) 1281da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 1291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (work) 1301da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds *work -= skb->truesize; 1316ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov atomic_sub(skb->truesize, &nf->mem); 1321da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds kfree_skb(skb); 1331da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 1341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 135c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanovstatic void ip4_frag_init(struct inet_frag_queue *q, void *a) 136c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov{ 137c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov struct ipq *qp = container_of(q, struct ipq, q); 138c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov struct ip4_create_arg *arg = a; 139c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov 140c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov qp->protocol = arg->iph->protocol; 141c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov qp->id = arg->iph->id; 142c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov qp->saddr = arg->iph->saddr; 143c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov qp->daddr = arg->iph->daddr; 144c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov qp->user = arg->user; 145c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov qp->peer = sysctl_ipfrag_max_dist ? 146c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov inet_getpeer(arg->iph->saddr, 1) : NULL; 147c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov} 148c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov 1491e4b82873af0f21002e37a81ef063d2e5410deb3Pavel Emelyanovstatic __inline__ void ip4_frag_free(struct inet_frag_queue *q) 1501da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 1511e4b82873af0f21002e37a81ef063d2e5410deb3Pavel Emelyanov struct ipq *qp; 1521e4b82873af0f21002e37a81ef063d2e5410deb3Pavel Emelyanov 1531e4b82873af0f21002e37a81ef063d2e5410deb3Pavel Emelyanov qp = container_of(q, struct ipq, q); 1541e4b82873af0f21002e37a81ef063d2e5410deb3Pavel Emelyanov if (qp->peer) 1551e4b82873af0f21002e37a81ef063d2e5410deb3Pavel Emelyanov inet_putpeer(qp->peer); 1561da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 1571da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1581da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1591da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* Destruction primitives. */ 1601da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1614b6cb5d8e3f5707d7a2e55cf7b05f1ea8bfc7a6dPavel Emelyanovstatic __inline__ void ipq_put(struct ipq *ipq) 1621da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 163762cc40801ad757a34527d5e548816cf3b6fc606Pavel Emelyanov inet_frag_put(&ipq->q, &ip4_frags); 1641da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 1651da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1661da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* Kill ipq entry. It is not destroyed immediately, 1671da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * because caller (and someone more) holds reference count. 1681da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 1691da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstatic void ipq_kill(struct ipq *ipq) 1701da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 171277e650ddfc6944ef5f5466fd898b8da7f06cd82Pavel Emelyanov inet_frag_kill(&ipq->q, &ip4_frags); 1721da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 1731da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 174e905a9edab7f4f14f9213b52234e4a346c690911YOSHIFUJI Hideaki/* Memory limiting on fragments. Evictor trashes the oldest 1751da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * fragment queue until we are back under the threshold. 1761da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 1776ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanovstatic void ip_evictor(struct net *net) 1781da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 1798e7999c44ee95e1e90ac91c83557a04e2948f160Pavel Emelyanov int evicted; 1808e7999c44ee95e1e90ac91c83557a04e2948f160Pavel Emelyanov 1816ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov evicted = inet_frag_evictor(&net->ipv4.frags, &ip4_frags); 1828e7999c44ee95e1e90ac91c83557a04e2948f160Pavel Emelyanov if (evicted) 183c5346fe396f5e22bbfb3ec037c43891c3c57d3e6Pavel Emelyanov IP_ADD_STATS_BH(net, IPSTATS_MIB_REASMFAILS, evicted); 1841da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 1851da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1861da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 1871da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Oops, a fragment queue timed out. Kill it and send an ICMP reply. 1881da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 1891da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstatic void ip_expire(unsigned long arg) 1901da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 191e521db9d790aaa60ae8920e21cb7faedc280fc36Pavel Emelyanov struct ipq *qp; 19284a3aa000eacbaf841d745b07ef3a3280899056bPavel Emelyanov struct net *net; 193e521db9d790aaa60ae8920e21cb7faedc280fc36Pavel Emelyanov 194e521db9d790aaa60ae8920e21cb7faedc280fc36Pavel Emelyanov qp = container_of((struct inet_frag_queue *) arg, struct ipq, q); 19584a3aa000eacbaf841d745b07ef3a3280899056bPavel Emelyanov net = container_of(qp->q.net, struct net, ipv4.frags); 1961da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1975ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov spin_lock(&qp->q.lock); 1981da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 199bc578a54f0fd489d0722303f9a52508495ccaf9aJoe Perches if (qp->q.last_in & INET_FRAG_COMPLETE) 2001da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto out; 2011da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2021da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ipq_kill(qp); 2031da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2047c73a6faffae0bfae70639113aecf06af666e714Pavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMTIMEOUT); 2057c73a6faffae0bfae70639113aecf06af666e714Pavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 2061da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 207bc578a54f0fd489d0722303f9a52508495ccaf9aJoe Perches if ((qp->q.last_in & INET_FRAG_FIRST_IN) && qp->q.fragments != NULL) { 2085ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov struct sk_buff *head = qp->q.fragments; 209cb84663e4d239f23f0d872bc6463c272e74daad8Denis V. Lunev 21069df9d5993bd7dd7499ad0e98fe824147fbe5667Eric Dumazet rcu_read_lock(); 21169df9d5993bd7dd7499ad0e98fe824147fbe5667Eric Dumazet head->dev = dev_get_by_index_rcu(net, qp->iif); 212e9017b55189355e9e6569990a18919e83f35bccbShan Wei if (!head->dev) 213e9017b55189355e9e6569990a18919e83f35bccbShan Wei goto out_rcu_unlock; 214e9017b55189355e9e6569990a18919e83f35bccbShan Wei 215e9017b55189355e9e6569990a18919e83f35bccbShan Wei /* 216e9017b55189355e9e6569990a18919e83f35bccbShan Wei * Only search router table for the head fragment, 217e9017b55189355e9e6569990a18919e83f35bccbShan Wei * when defraging timeout at PRE_ROUTING HOOK. 218e9017b55189355e9e6569990a18919e83f35bccbShan Wei */ 219e9017b55189355e9e6569990a18919e83f35bccbShan Wei if (qp->user == IP_DEFRAG_CONNTRACK_IN && !skb_dst(head)) { 220e9017b55189355e9e6569990a18919e83f35bccbShan Wei const struct iphdr *iph = ip_hdr(head); 221e9017b55189355e9e6569990a18919e83f35bccbShan Wei int err = ip_route_input(head, iph->daddr, iph->saddr, 222e9017b55189355e9e6569990a18919e83f35bccbShan Wei iph->tos, head->dev); 223e9017b55189355e9e6569990a18919e83f35bccbShan Wei if (unlikely(err)) 224e9017b55189355e9e6569990a18919e83f35bccbShan Wei goto out_rcu_unlock; 225e9017b55189355e9e6569990a18919e83f35bccbShan Wei 226e9017b55189355e9e6569990a18919e83f35bccbShan Wei /* 227e9017b55189355e9e6569990a18919e83f35bccbShan Wei * Only an end host needs to send an ICMP 228e9017b55189355e9e6569990a18919e83f35bccbShan Wei * "Fragment Reassembly Timeout" message, per RFC792. 229e9017b55189355e9e6569990a18919e83f35bccbShan Wei */ 230e9017b55189355e9e6569990a18919e83f35bccbShan Wei if (skb_rtable(head)->rt_type != RTN_LOCAL) 231e9017b55189355e9e6569990a18919e83f35bccbShan Wei goto out_rcu_unlock; 232e9017b55189355e9e6569990a18919e83f35bccbShan Wei 233e9017b55189355e9e6569990a18919e83f35bccbShan Wei } 234e9017b55189355e9e6569990a18919e83f35bccbShan Wei 235e9017b55189355e9e6569990a18919e83f35bccbShan Wei /* Send an ICMP "Fragment Reassembly Timeout" message. */ 236e9017b55189355e9e6569990a18919e83f35bccbShan Wei icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0); 237e9017b55189355e9e6569990a18919e83f35bccbShan Weiout_rcu_unlock: 238d1c9ae6d1e7b95cedc8e39e8949e795379a0669ePatrick McHardy rcu_read_unlock(); 239d1c9ae6d1e7b95cedc8e39e8949e795379a0669ePatrick McHardy } 2401da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsout: 2415ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov spin_unlock(&qp->q.lock); 2424b6cb5d8e3f5707d7a2e55cf7b05f1ea8bfc7a6dPavel Emelyanov ipq_put(qp); 2431da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 2441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 245abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov/* Find the correct entry in the "incomplete datagrams" queue for 246abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov * this IP datagram, and create new one, if nothing is found. 247abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov */ 248ac18e7509e7df327e30d6e073a787d922eaf211dPavel Emelyanovstatic inline struct ipq *ip_find(struct net *net, struct iphdr *iph, u32 user) 2491da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 250c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov struct inet_frag_queue *q; 251c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov struct ip4_create_arg arg; 252abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov unsigned int hash; 2531da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 254c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov arg.iph = iph; 255c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov arg.user = user; 2569a375803feaadb6c34e0807bd9325885dcca5c00Pavel Emelyanov 2579a375803feaadb6c34e0807bd9325885dcca5c00Pavel Emelyanov read_lock(&ip4_frags.lock); 258abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol); 2591da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 260ac18e7509e7df327e30d6e073a787d922eaf211dPavel Emelyanov q = inet_frag_find(&net->ipv4.frags, &ip4_frags, &arg, hash); 261c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov if (q == NULL) 262c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov goto out_nomem; 2631da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 264c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov return container_of(q, struct ipq, q); 2651da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2661da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsout_nomem: 26764ce207306debd7157f47282be94770407bec01cPatrick McHardy LIMIT_NETDEBUG(KERN_ERR "ip_frag_create: no memory left !\n"); 2681da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return NULL; 2691da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 2701da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 27189cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu/* Is the fragment too far ahead to be part of ipq? */ 27289cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xustatic inline int ip_frag_too_far(struct ipq *qp) 27389cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu{ 27489cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu struct inet_peer *peer = qp->peer; 27589cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu unsigned int max = sysctl_ipfrag_max_dist; 27689cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu unsigned int start, end; 27789cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 27889cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu int rc; 27989cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 28089cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu if (!peer || !max) 28189cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu return 0; 28289cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 28389cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu start = qp->rid; 28489cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu end = atomic_inc_return(&peer->rid); 28589cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu qp->rid = end; 28689cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 2875ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov rc = qp->q.fragments && (end - start) > max; 28889cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 28989cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu if (rc) { 2907c73a6faffae0bfae70639113aecf06af666e714Pavel Emelyanov struct net *net; 2917c73a6faffae0bfae70639113aecf06af666e714Pavel Emelyanov 2927c73a6faffae0bfae70639113aecf06af666e714Pavel Emelyanov net = container_of(qp->q.net, struct net, ipv4.frags); 2937c73a6faffae0bfae70639113aecf06af666e714Pavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 29489cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu } 29589cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 29689cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu return rc; 29789cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu} 29889cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 29989cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xustatic int ip_frag_reinit(struct ipq *qp) 30089cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu{ 30189cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu struct sk_buff *fp; 30289cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 303b2fd5321dd160ef309dfb6cfc78ed8de4a830659Pavel Emelyanov if (!mod_timer(&qp->q.timer, jiffies + qp->q.net->timeout)) { 3045ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov atomic_inc(&qp->q.refcnt); 30589cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu return -ETIMEDOUT; 30689cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu } 30789cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 3085ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov fp = qp->q.fragments; 30989cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu do { 31089cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu struct sk_buff *xp = fp->next; 3116ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov frag_kfree_skb(qp->q.net, fp, NULL); 31289cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu fp = xp; 31389cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu } while (fp); 31489cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 3155ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.last_in = 0; 3165ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.len = 0; 3175ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.meat = 0; 3185ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.fragments = NULL; 31989cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu qp->iif = 0; 32089cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 32189cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu return 0; 32289cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu} 32389cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 3241da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* Add new segment to existing queue. */ 3251706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xustatic int ip_frag_queue(struct ipq *qp, struct sk_buff *skb) 3261da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 3271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds struct sk_buff *prev, *next; 3281706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu struct net_device *dev; 3291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int flags, offset; 3301da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int ihl, end; 3311706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu int err = -ENOENT; 3321da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 333bc578a54f0fd489d0722303f9a52508495ccaf9aJoe Perches if (qp->q.last_in & INET_FRAG_COMPLETE) 3341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto err; 3351da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 33689cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu if (!(IPCB(skb)->flags & IPSKB_FRAG_COMPLETE) && 3371706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu unlikely(ip_frag_too_far(qp)) && 3381706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu unlikely(err = ip_frag_reinit(qp))) { 33989cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu ipq_kill(qp); 34089cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu goto err; 34189cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu } 34289cee8b1cbb9dac40c92ef1968aea2b45f82fd18Herbert Xu 343eddc9ec53be2ecdbf4efe0efd4a83052594f0ac0Arnaldo Carvalho de Melo offset = ntohs(ip_hdr(skb)->frag_off); 3441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds flags = offset & ~IP_OFFSET; 3451da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds offset &= IP_OFFSET; 3461da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds offset <<= 3; /* offset is in 8-byte chunks */ 347c9bdd4b5257406b0608385d19c40b5511decf4f6Arnaldo Carvalho de Melo ihl = ip_hdrlen(skb); 3481da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3491da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Determine the position of this fragment. */ 350e905a9edab7f4f14f9213b52234e4a346c690911YOSHIFUJI Hideaki end = offset + skb->len - ihl; 3511706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu err = -EINVAL; 3521da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3531da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Is this the final fragment? */ 3541da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if ((flags & IP_MF) == 0) { 3551da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* If we already have some bits beyond end 3561da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * or have different end, the segment is corrrupted. 3571da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 3585ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov if (end < qp->q.len || 359bc578a54f0fd489d0722303f9a52508495ccaf9aJoe Perches ((qp->q.last_in & INET_FRAG_LAST_IN) && end != qp->q.len)) 3601da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto err; 361bc578a54f0fd489d0722303f9a52508495ccaf9aJoe Perches qp->q.last_in |= INET_FRAG_LAST_IN; 3625ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.len = end; 3631da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } else { 3641da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (end&7) { 3651da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds end &= ~7; 3661da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (skb->ip_summed != CHECKSUM_UNNECESSARY) 3671da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds skb->ip_summed = CHECKSUM_NONE; 3681da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 3695ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov if (end > qp->q.len) { 3701da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Some bits beyond end -> corruption. */ 371bc578a54f0fd489d0722303f9a52508495ccaf9aJoe Perches if (qp->q.last_in & INET_FRAG_LAST_IN) 3721da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto err; 3735ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.len = end; 3741da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 3751da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 3761da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (end == offset) 3771da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto err; 3781da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3791706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu err = -ENOMEM; 3801da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (pskb_pull(skb, ihl) == NULL) 3811da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto err; 3821706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu 3831706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu err = pskb_trim_rcsum(skb, end - offset); 3841706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu if (err) 3851da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto err; 3861da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3871da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Find out which fragments are in front and at the back of us 3881da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * in the chain of fragments so far. We must know where to put 3891da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * this fragment, right? 3901da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 3911da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds prev = NULL; 3925ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov for (next = qp->q.fragments; next != NULL; next = next->next) { 3931da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (FRAG_CB(next)->offset >= offset) 3941da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds break; /* bingo! */ 3951da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds prev = next; 3961da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 3971da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3981da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* We found where to put this one. Check for overlap with 3991da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * preceding fragment, and, if needed, align things so that 4001da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * any overlaps are eliminated. 4011da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 4021da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (prev) { 4031da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int i = (FRAG_CB(prev)->offset + prev->len) - offset; 4041da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4051da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (i > 0) { 4061da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds offset += i; 4071706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu err = -EINVAL; 4081da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (end <= offset) 4091da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto err; 4101706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu err = -ENOMEM; 4111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!pskb_pull(skb, i)) 4121da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto err; 4131da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (skb->ip_summed != CHECKSUM_UNNECESSARY) 4141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds skb->ip_summed = CHECKSUM_NONE; 4151da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 4161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 4171da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4181706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu err = -ENOMEM; 4191706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu 4201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds while (next && FRAG_CB(next)->offset < end) { 4211da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int i = end - FRAG_CB(next)->offset; /* overlap is 'i' bytes */ 4221da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4231da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (i < next->len) { 4241da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Eat head of the next overlapped fragment 4251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * and leave the loop. The next ones cannot overlap. 4261da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 4271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!pskb_pull(next, i)) 4281da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto err; 4291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds FRAG_CB(next)->offset += i; 4305ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.meat -= i; 4311da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (next->ip_summed != CHECKSUM_UNNECESSARY) 4321da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds next->ip_summed = CHECKSUM_NONE; 4331da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds break; 4341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } else { 4351da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds struct sk_buff *free_it = next; 4361da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 43747c6bf7760bb8021bf7782f05bcd3b9f73ed2c2ePeter Zijlstra /* Old fragment is completely overridden with 4381da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * new one drop it. 4391da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 4401da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds next = next->next; 4411da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4421da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (prev) 4431da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds prev->next = next; 4441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds else 4455ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.fragments = next; 4461da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4475ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.meat -= free_it->len; 4486ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov frag_kfree_skb(qp->q.net, free_it, NULL); 4491da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 4501da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 4511da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4521da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds FRAG_CB(skb)->offset = offset; 4531da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4541da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Insert this fragment in the chain of fragments. */ 4551da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds skb->next = next; 4561da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (prev) 4571da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds prev->next = skb; 4581da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds else 4595ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.fragments = skb; 4601da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4611706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu dev = skb->dev; 4621706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu if (dev) { 4631706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu qp->iif = dev->ifindex; 4641706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu skb->dev = NULL; 4651706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu } 4665ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.stamp = skb->tstamp; 4675ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.meat += skb->len; 4686ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov atomic_add(skb->truesize, &qp->q.net->mem); 4691da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (offset == 0) 470bc578a54f0fd489d0722303f9a52508495ccaf9aJoe Perches qp->q.last_in |= INET_FRAG_FIRST_IN; 4711da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 472bc578a54f0fd489d0722303f9a52508495ccaf9aJoe Perches if (qp->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && 473bc578a54f0fd489d0722303f9a52508495ccaf9aJoe Perches qp->q.meat == qp->q.len) 4741706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu return ip_frag_reasm(qp, prev, dev); 4751706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu 4767eb95156d9dce2f59794264db336ce007d71638bPavel Emelyanov write_lock(&ip4_frags.lock); 4773140c25c82106645a6b1fc469dab7006a1d09fd0Pavel Emelyanov list_move_tail(&qp->q.lru_list, &qp->q.net->lru_list); 4787eb95156d9dce2f59794264db336ce007d71638bPavel Emelyanov write_unlock(&ip4_frags.lock); 4791706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu return -EINPROGRESS; 4801da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4811da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldserr: 4821da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds kfree_skb(skb); 4831706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu return err; 4841da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 4851da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4861da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4871da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* Build a new IP datagram from all its fragments. */ 4881da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4891706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xustatic int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, 4901706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu struct net_device *dev) 4911da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 4922bad35b7c9588eb5e65c03bcae54e7eb6b1a6504Jorge Boncompte [DTI struct net *net = container_of(qp->q.net, struct net, ipv4.frags); 4931da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds struct iphdr *iph; 4945ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov struct sk_buff *fp, *head = qp->q.fragments; 4951da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int len; 4961da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int ihlen; 4971706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu int err; 4981da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4991da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ipq_kill(qp); 5001da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5011706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu /* Make the one we just received the head. */ 5021706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu if (prev) { 5031706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu head = prev->next; 5041706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu fp = skb_clone(head, GFP_ATOMIC); 5051706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu if (!fp) 5061706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu goto out_nomem; 5071706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu 5081706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu fp->next = head->next; 5091706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu prev->next = fp; 5101706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu 5115ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov skb_morph(head, qp->q.fragments); 5125ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov head->next = qp->q.fragments->next; 5131706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu 5145ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov kfree_skb(qp->q.fragments); 5155ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.fragments = head; 5161706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu } 5171706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu 518547b792cac0a038b9dbf958d3c120df3740b5572Ilpo Järvinen WARN_ON(head == NULL); 519547b792cac0a038b9dbf958d3c120df3740b5572Ilpo Järvinen WARN_ON(FRAG_CB(head)->offset != 0); 5201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5211da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Allocate a new buffer for the datagram. */ 522c9bdd4b5257406b0608385d19c40b5511decf4f6Arnaldo Carvalho de Melo ihlen = ip_hdrlen(head); 5235ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov len = ihlen + qp->q.len; 5241da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5251706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu err = -E2BIG; 526132adf54639cf7dd9315e8df89c2faa59f6e46d9Stephen Hemminger if (len > 65535) 5271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto out_oversize; 5281da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Head of list must not be cloned. */ 5301da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) 5311da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto out_nomem; 5321da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5331da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* If the first fragment is fragmented itself, we split 5341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * it to two chunks: the first with data and paged part 5351da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * and the second, holding only fragments. */ 536d7fcf1a5cae2c970e9afe7192fe0c13d931247e0David S. Miller if (skb_has_frags(head)) { 5371da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds struct sk_buff *clone; 5381da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int i, plen = 0; 5391da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5401da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) 5411da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto out_nomem; 5421da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds clone->next = head->next; 5431da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds head->next = clone; 5441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; 545d7fcf1a5cae2c970e9afe7192fe0c13d931247e0David S. Miller skb_frag_list_init(head); 5461da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds for (i=0; i<skb_shinfo(head)->nr_frags; i++) 5471da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds plen += skb_shinfo(head)->frags[i].size; 5481da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds clone->len = clone->data_len = head->data_len - plen; 5491da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds head->data_len -= clone->len; 5501da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds head->len -= clone->len; 5511da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds clone->csum = 0; 5521da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds clone->ip_summed = head->ip_summed; 5536ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov atomic_add(clone->truesize, &qp->q.net->mem); 5541da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 5551da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5561da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds skb_shinfo(head)->frag_list = head->next; 557d56f90a7c96da5187f0cdf07ee7434fe6aa78bbcArnaldo Carvalho de Melo skb_push(head, head->data - skb_network_header(head)); 5586ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov atomic_sub(head->truesize, &qp->q.net->mem); 5591da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5601da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds for (fp=head->next; fp; fp = fp->next) { 5611da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds head->data_len += fp->len; 5621da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds head->len += fp->len; 5631da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (head->ip_summed != fp->ip_summed) 5641da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds head->ip_summed = CHECKSUM_NONE; 56584fa7933a33f806bbbaae6775e87459b1ec584c0Patrick McHardy else if (head->ip_summed == CHECKSUM_COMPLETE) 5661da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds head->csum = csum_add(head->csum, fp->csum); 5671da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds head->truesize += fp->truesize; 5686ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov atomic_sub(fp->truesize, &qp->q.net->mem); 5691da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 5701da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5711da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds head->next = NULL; 5721da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds head->dev = dev; 5735ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov head->tstamp = qp->q.stamp; 5741da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 575eddc9ec53be2ecdbf4efe0efd4a83052594f0ac0Arnaldo Carvalho de Melo iph = ip_hdr(head); 5761da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds iph->frag_off = 0; 5771da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds iph->tot_len = htons(len); 5782bad35b7c9588eb5e65c03bcae54e7eb6b1a6504Jorge Boncompte [DTI IP_INC_STATS_BH(net, IPSTATS_MIB_REASMOKS); 5795ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov qp->q.fragments = NULL; 5801706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu return 0; 5811da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5821da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsout_nomem: 583e905a9edab7f4f14f9213b52234e4a346c690911YOSHIFUJI Hideaki LIMIT_NETDEBUG(KERN_ERR "IP: queue_glue: no memory for gluing " 58464ce207306debd7157f47282be94770407bec01cPatrick McHardy "queue %p\n", qp); 58545542479fb261342d5244869cf3ca4636b7ffd43David Howells err = -ENOMEM; 5861da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto out_fail; 5871da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsout_oversize: 5881da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (net_ratelimit()) 589673d57e72398edfedc93fb50ff58048077c9d587Harvey Harrison printk(KERN_INFO "Oversized IP packet from %pI4.\n", 590673d57e72398edfedc93fb50ff58048077c9d587Harvey Harrison &qp->saddr); 5911da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsout_fail: 592bbf31bf18d34caa87dd01f08bf713635593697f2David Ford IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 5931706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu return err; 5941da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 5951da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5961da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* Process an incoming IP datagram fragment. */ 597776c729e8d91b2740583a2169678f2d3f383458bHerbert Xuint ip_defrag(struct sk_buff *skb, u32 user) 5981da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 5991da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds struct ipq *qp; 600ac18e7509e7df327e30d6e073a787d922eaf211dPavel Emelyanov struct net *net; 601e905a9edab7f4f14f9213b52234e4a346c690911YOSHIFUJI Hideaki 602adf30907d63893e4208dfe3f5c88ae12bc2f25d5Eric Dumazet net = skb->dev ? dev_net(skb->dev) : dev_net(skb_dst(skb)->dev); 6037c73a6faffae0bfae70639113aecf06af666e714Pavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMREQDS); 6041da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 6051da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Start by cleaning up the memory. */ 606e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov if (atomic_read(&net->ipv4.frags.mem) > net->ipv4.frags.high_thresh) 6076ddc082223ef0f73717b4133fa7e648842bbfd02Pavel Emelyanov ip_evictor(net); 6081da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 6091da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Lookup (or create) queue header */ 610ac18e7509e7df327e30d6e073a787d922eaf211dPavel Emelyanov if ((qp = ip_find(net, ip_hdr(skb), user)) != NULL) { 6111706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu int ret; 6121da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 6135ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov spin_lock(&qp->q.lock); 6141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 6151706d58763c36133d7fce6cc78b1444fd40db28cHerbert Xu ret = ip_frag_queue(qp, skb); 6161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 6175ab11c98d3a950faf6922b6166e5f8fc874590e7Pavel Emelyanov spin_unlock(&qp->q.lock); 6184b6cb5d8e3f5707d7a2e55cf7b05f1ea8bfc7a6dPavel Emelyanov ipq_put(qp); 619776c729e8d91b2740583a2169678f2d3f383458bHerbert Xu return ret; 6201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 6211da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 6227c73a6faffae0bfae70639113aecf06af666e714Pavel Emelyanov IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); 6231da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds kfree_skb(skb); 624776c729e8d91b2740583a2169678f2d3f383458bHerbert Xu return -ENOMEM; 6251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 6261da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 6278d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov#ifdef CONFIG_SYSCTL 6288d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanovstatic int zero; 6298d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov 6300a64b4b811025ce0386ad84d81504e4ff7985856Pavel Emelyanovstatic struct ctl_table ip4_frags_ns_ctl_table[] = { 6318d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov { 6328d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .procname = "ipfrag_high_thresh", 633e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov .data = &init_net.ipv4.frags.high_thresh, 6348d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .maxlen = sizeof(int), 6358d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .mode = 0644, 6366d9f239a1edb31d6133230f478fd1dc2da338ec5Alexey Dobriyan .proc_handler = proc_dointvec 6378d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov }, 6388d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov { 6398d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .procname = "ipfrag_low_thresh", 640e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov .data = &init_net.ipv4.frags.low_thresh, 6418d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .maxlen = sizeof(int), 6428d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .mode = 0644, 6436d9f239a1edb31d6133230f478fd1dc2da338ec5Alexey Dobriyan .proc_handler = proc_dointvec 6448d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov }, 6458d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov { 6468d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .procname = "ipfrag_time", 647b2fd5321dd160ef309dfb6cfc78ed8de4a830659Pavel Emelyanov .data = &init_net.ipv4.frags.timeout, 6488d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .maxlen = sizeof(int), 6498d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .mode = 0644, 6506d9f239a1edb31d6133230f478fd1dc2da338ec5Alexey Dobriyan .proc_handler = proc_dointvec_jiffies, 6518d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov }, 6527d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov { } 6537d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov}; 6547d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov 6557d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanovstatic struct ctl_table ip4_frags_ctl_table[] = { 6568d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov { 6578d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .procname = "ipfrag_secret_interval", 6583b4bc4a2bfe80d01ebd4f2b6dcc58986c970ed16Pavel Emelyanov .data = &ip4_frags.secret_interval, 6598d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .maxlen = sizeof(int), 6608d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .mode = 0644, 6616d9f239a1edb31d6133230f478fd1dc2da338ec5Alexey Dobriyan .proc_handler = proc_dointvec_jiffies, 6628d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov }, 6638d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov { 6648d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .procname = "ipfrag_max_dist", 6658d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .data = &sysctl_ipfrag_max_dist, 6668d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .maxlen = sizeof(int), 6678d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .mode = 0644, 6686d9f239a1edb31d6133230f478fd1dc2da338ec5Alexey Dobriyan .proc_handler = proc_dointvec_minmax, 6698d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov .extra1 = &zero 6708d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov }, 6718d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov { } 6728d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov}; 6738d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov 6742c8c1e7297e19bdef3c178c3ea41d898a7716e3eAlexey Dobriyanstatic int __net_init ip4_frags_ns_ctl_register(struct net *net) 6758d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov{ 676e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov struct ctl_table *table; 6778d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov struct ctl_table_header *hdr; 6788d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov 6790a64b4b811025ce0386ad84d81504e4ff7985856Pavel Emelyanov table = ip4_frags_ns_ctl_table; 68009ad9bc752519cc167d0a573e1acf69b5c707c67Octavian Purdila if (!net_eq(net, &init_net)) { 6810a64b4b811025ce0386ad84d81504e4ff7985856Pavel Emelyanov table = kmemdup(table, sizeof(ip4_frags_ns_ctl_table), GFP_KERNEL); 682e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov if (table == NULL) 683e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov goto err_alloc; 684e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov 685e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov table[0].data = &net->ipv4.frags.high_thresh; 686e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov table[1].data = &net->ipv4.frags.low_thresh; 687b2fd5321dd160ef309dfb6cfc78ed8de4a830659Pavel Emelyanov table[2].data = &net->ipv4.frags.timeout; 688e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov } 689e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov 690e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov hdr = register_net_sysctl_table(net, net_ipv4_ctl_path, table); 691e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov if (hdr == NULL) 692e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov goto err_reg; 693e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov 694e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov net->ipv4.frags_hdr = hdr; 695e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov return 0; 696e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov 697e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanoverr_reg: 69809ad9bc752519cc167d0a573e1acf69b5c707c67Octavian Purdila if (!net_eq(net, &init_net)) 699e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov kfree(table); 700e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanoverr_alloc: 701e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov return -ENOMEM; 702e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov} 703e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov 7042c8c1e7297e19bdef3c178c3ea41d898a7716e3eAlexey Dobriyanstatic void __net_exit ip4_frags_ns_ctl_unregister(struct net *net) 705e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov{ 706e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov struct ctl_table *table; 707e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov 708e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov table = net->ipv4.frags_hdr->ctl_table_arg; 709e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov unregister_net_sysctl_table(net->ipv4.frags_hdr); 710e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov kfree(table); 7118d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov} 7127d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov 7137d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanovstatic void ip4_frags_ctl_register(void) 7147d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov{ 7157d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov register_net_sysctl_rotable(net_ipv4_ctl_path, ip4_frags_ctl_table); 7167d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov} 7178d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov#else 7180a64b4b811025ce0386ad84d81504e4ff7985856Pavel Emelyanovstatic inline int ip4_frags_ns_ctl_register(struct net *net) 7198d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov{ 7208d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov return 0; 7218d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov} 722e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov 7230a64b4b811025ce0386ad84d81504e4ff7985856Pavel Emelyanovstatic inline void ip4_frags_ns_ctl_unregister(struct net *net) 724e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov{ 725e4a2d5c2bccd5bd29de5ae4f14ff4448fac9cfc8Pavel Emelyanov} 7267d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov 7277d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanovstatic inline void ip4_frags_ctl_register(void) 7287d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov{ 7297d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov} 7308d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov#endif 7318d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov 7322c8c1e7297e19bdef3c178c3ea41d898a7716e3eAlexey Dobriyanstatic int __net_init ipv4_frags_init_net(struct net *net) 7338d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov{ 734b2fd5321dd160ef309dfb6cfc78ed8de4a830659Pavel Emelyanov /* 735e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov * Fragment cache limits. We will commit 256K at one time. Should we 736e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov * cross that limit we will prune down to 192K. This should cope with 737e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov * even the most extreme cases without allowing an attacker to 738e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov * measurably harm machine performance. 739e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov */ 740e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov net->ipv4.frags.high_thresh = 256 * 1024; 741e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov net->ipv4.frags.low_thresh = 192 * 1024; 742e31e0bdc7e7fb9a4b09d2f3266c035a18fdcee9dPavel Emelyanov /* 743b2fd5321dd160ef309dfb6cfc78ed8de4a830659Pavel Emelyanov * Important NOTE! Fragment queue must be destroyed before MSL expires. 744b2fd5321dd160ef309dfb6cfc78ed8de4a830659Pavel Emelyanov * RFC791 is wrong proposing to prolongate timer each fragment arrival 745b2fd5321dd160ef309dfb6cfc78ed8de4a830659Pavel Emelyanov * by TTL. 746b2fd5321dd160ef309dfb6cfc78ed8de4a830659Pavel Emelyanov */ 747b2fd5321dd160ef309dfb6cfc78ed8de4a830659Pavel Emelyanov net->ipv4.frags.timeout = IP_FRAG_TIME; 748b2fd5321dd160ef309dfb6cfc78ed8de4a830659Pavel Emelyanov 749e5a2bb842cd9681d00d4ca963e63e4d3647e66f8Pavel Emelyanov inet_frags_init_net(&net->ipv4.frags); 750e5a2bb842cd9681d00d4ca963e63e4d3647e66f8Pavel Emelyanov 7510a64b4b811025ce0386ad84d81504e4ff7985856Pavel Emelyanov return ip4_frags_ns_ctl_register(net); 7528d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov} 7538d8354d2fb9277f165715a6e1cb92bcc89259975Pavel Emelyanov 7542c8c1e7297e19bdef3c178c3ea41d898a7716e3eAlexey Dobriyanstatic void __net_exit ipv4_frags_exit_net(struct net *net) 75581566e8322c3f6c6f9a2277fe0e440fee8d917bdPavel Emelyanov{ 7560a64b4b811025ce0386ad84d81504e4ff7985856Pavel Emelyanov ip4_frags_ns_ctl_unregister(net); 75781566e8322c3f6c6f9a2277fe0e440fee8d917bdPavel Emelyanov inet_frags_exit_net(&net->ipv4.frags, &ip4_frags); 75881566e8322c3f6c6f9a2277fe0e440fee8d917bdPavel Emelyanov} 75981566e8322c3f6c6f9a2277fe0e440fee8d917bdPavel Emelyanov 76081566e8322c3f6c6f9a2277fe0e440fee8d917bdPavel Emelyanovstatic struct pernet_operations ip4_frags_ops = { 76181566e8322c3f6c6f9a2277fe0e440fee8d917bdPavel Emelyanov .init = ipv4_frags_init_net, 76281566e8322c3f6c6f9a2277fe0e440fee8d917bdPavel Emelyanov .exit = ipv4_frags_exit_net, 76381566e8322c3f6c6f9a2277fe0e440fee8d917bdPavel Emelyanov}; 76481566e8322c3f6c6f9a2277fe0e440fee8d917bdPavel Emelyanov 765b7aa0bf70c4afb9e38be25f5c0922498d0f8684cEric Dumazetvoid __init ipfrag_init(void) 7661da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 7677d291ebb834278e30c211b26fb7076adcb636ad9Pavel Emelyanov ip4_frags_ctl_register(); 76881566e8322c3f6c6f9a2277fe0e440fee8d917bdPavel Emelyanov register_pernet_subsys(&ip4_frags_ops); 769321a3a99e4717b960e21c62fc6a140d21453df7fPavel Emelyanov ip4_frags.hashfn = ip4_hashfn; 770c6fda282294da882f8d8cc4c513940277dd380f5Pavel Emelyanov ip4_frags.constructor = ip4_frag_init; 7711e4b82873af0f21002e37a81ef063d2e5410deb3Pavel Emelyanov ip4_frags.destructor = ip4_frag_free; 7721e4b82873af0f21002e37a81ef063d2e5410deb3Pavel Emelyanov ip4_frags.skb_free = NULL; 7731e4b82873af0f21002e37a81ef063d2e5410deb3Pavel Emelyanov ip4_frags.qsize = sizeof(struct ipq); 774abd6523d15f40bfee14652619a31a7f65f77f581Pavel Emelyanov ip4_frags.match = ip4_frag_match; 775e521db9d790aaa60ae8920e21cb7faedc280fc36Pavel Emelyanov ip4_frags.frag_expire = ip_expire; 7763b4bc4a2bfe80d01ebd4f2b6dcc58986c970ed16Pavel Emelyanov ip4_frags.secret_interval = 10 * 60 * HZ; 7777eb95156d9dce2f59794264db336ce007d71638bPavel Emelyanov inet_frags_init(&ip4_frags); 7781da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 7791da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 7801da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus TorvaldsEXPORT_SYMBOL(ip_defrag); 781