Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
| 3 | * operating system. INET is implemented using the BSD Socket |
| 4 | * interface as the means of communication with the user level. |
| 5 | * |
| 6 | * The IP fragmentation functionality. |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 7 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | * Version: $Id: ip_fragment.c,v 1.59 2002/01/12 07:54:56 davem Exp $ |
| 9 | * |
| 10 | * Authors: Fred N. van Kempen <waltje@uWalt.NL.Mugnet.ORG> |
| 11 | * Alan Cox <Alan.Cox@linux.org> |
| 12 | * |
| 13 | * Fixes: |
| 14 | * Alan Cox : Split from ip.c , see ip_input.c for history. |
| 15 | * David S. Miller : Begin massive cleanup... |
| 16 | * Andi Kleen : Add sysctls. |
| 17 | * xxxx : Overlapfrag bug. |
| 18 | * Ultima : ip_expire() kernel panic. |
| 19 | * Bill Hawes : Frag accounting and evictor fixes. |
| 20 | * John McDonald : 0 length frag bug. |
| 21 | * Alexey Kuznetsov: SMP races, threading, cleanup. |
| 22 | * Patrick McHardy : LRU queue of frag heads for evictor. |
| 23 | */ |
| 24 | |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 25 | #include <linux/compiler.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | #include <linux/module.h> |
| 27 | #include <linux/types.h> |
| 28 | #include <linux/mm.h> |
| 29 | #include <linux/jiffies.h> |
| 30 | #include <linux/skbuff.h> |
| 31 | #include <linux/list.h> |
| 32 | #include <linux/ip.h> |
| 33 | #include <linux/icmp.h> |
| 34 | #include <linux/netdevice.h> |
| 35 | #include <linux/jhash.h> |
| 36 | #include <linux/random.h> |
| 37 | #include <net/sock.h> |
| 38 | #include <net/ip.h> |
| 39 | #include <net/icmp.h> |
| 40 | #include <net/checksum.h> |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 41 | #include <net/inetpeer.h> |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 42 | #include <net/inet_frag.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | #include <linux/tcp.h> |
| 44 | #include <linux/udp.h> |
| 45 | #include <linux/inet.h> |
| 46 | #include <linux/netfilter_ipv4.h> |
| 47 | |
| 48 | /* NOTE. Logic of IP defragmentation is parallel to corresponding IPv6 |
| 49 | * code now. If you change something here, _PLEASE_ update ipv6/reassembly.c |
| 50 | * as well. Or notify me, at least. --ANK |
| 51 | */ |
| 52 | |
Brian Haley | ab32ea5 | 2006-09-22 14:15:41 -0700 | [diff] [blame] | 53 | int sysctl_ipfrag_max_dist __read_mostly = 64; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 54 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | struct ipfrag_skb_cb |
| 56 | { |
| 57 | struct inet_skb_parm h; |
| 58 | int offset; |
| 59 | }; |
| 60 | |
| 61 | #define FRAG_CB(skb) ((struct ipfrag_skb_cb*)((skb)->cb)) |
| 62 | |
| 63 | /* Describe an entry in the "incomplete datagrams" queue. */ |
| 64 | struct ipq { |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 65 | struct inet_frag_queue q; |
| 66 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | u32 user; |
Al Viro | 1827777 | 2006-09-26 22:19:02 -0700 | [diff] [blame] | 68 | __be32 saddr; |
| 69 | __be32 daddr; |
| 70 | __be16 id; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | u8 protocol; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 72 | int iif; |
| 73 | unsigned int rid; |
| 74 | struct inet_peer *peer; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | }; |
| 76 | |
Pavel Emelyanov | 04128f2 | 2007-10-15 02:33:45 -0700 | [diff] [blame] | 77 | struct inet_frags_ctl ip4_frags_ctl __read_mostly = { |
| 78 | /* |
| 79 | * Fragment cache limits. We will commit 256K at one time. Should we |
| 80 | * cross that limit we will prune down to 192K. This should cope with |
| 81 | * even the most extreme cases without allowing an attacker to |
| 82 | * measurably harm machine performance. |
| 83 | */ |
| 84 | .high_thresh = 256 * 1024, |
| 85 | .low_thresh = 192 * 1024, |
| 86 | |
| 87 | /* |
| 88 | * Important NOTE! Fragment queue must be destroyed before MSL expires. |
| 89 | * RFC791 is wrong proposing to prolongate timer each fragment arrival |
| 90 | * by TTL. |
| 91 | */ |
| 92 | .timeout = IP_FRAG_TIME, |
| 93 | .secret_interval = 10 * 60 * HZ, |
| 94 | }; |
| 95 | |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 96 | static struct inet_frags ip4_frags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 98 | int ip_frag_nqueues(void) |
| 99 | { |
| 100 | return ip4_frags.nqueues; |
| 101 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 103 | int ip_frag_mem(void) |
| 104 | { |
| 105 | return atomic_read(&ip4_frags.mem); |
| 106 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 108 | static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, |
| 109 | struct net_device *dev); |
| 110 | |
Al Viro | 1827777 | 2006-09-26 22:19:02 -0700 | [diff] [blame] | 111 | static unsigned int ipqhashfn(__be16 id, __be32 saddr, __be32 daddr, u8 prot) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | { |
Al Viro | 1827777 | 2006-09-26 22:19:02 -0700 | [diff] [blame] | 113 | return jhash_3words((__force u32)id << 16 | prot, |
| 114 | (__force u32)saddr, (__force u32)daddr, |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 115 | ip4_frags.rnd) & (INETFRAGS_HASHSZ - 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | } |
| 117 | |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 118 | static unsigned int ip4_hashfn(struct inet_frag_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | { |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 120 | struct ipq *ipq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 122 | ipq = container_of(q, struct ipq, q); |
| 123 | return ipqhashfn(ipq->id, ipq->saddr, ipq->daddr, ipq->protocol); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | } |
| 125 | |
Pavel Emelyanov | 2588fe1 | 2007-10-17 19:44:34 -0700 | [diff] [blame] | 126 | static int ip4_frag_equal(struct inet_frag_queue *q1, |
| 127 | struct inet_frag_queue *q2) |
| 128 | { |
| 129 | struct ipq *qp1, *qp2; |
| 130 | |
| 131 | qp1 = container_of(q1, struct ipq, q); |
| 132 | qp2 = container_of(q2, struct ipq, q); |
| 133 | return (qp1->id == qp2->id && |
| 134 | qp1->saddr == qp2->saddr && |
| 135 | qp1->daddr == qp2->daddr && |
| 136 | qp1->protocol == qp2->protocol && |
| 137 | qp1->user == qp2->user); |
| 138 | } |
| 139 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | /* Memory Tracking Functions. */ |
| 141 | static __inline__ void frag_kfree_skb(struct sk_buff *skb, int *work) |
| 142 | { |
| 143 | if (work) |
| 144 | *work -= skb->truesize; |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 145 | atomic_sub(skb->truesize, &ip4_frags.mem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | kfree_skb(skb); |
| 147 | } |
| 148 | |
Pavel Emelyanov | 1e4b828 | 2007-10-15 02:39:14 -0700 | [diff] [blame] | 149 | static __inline__ void ip4_frag_free(struct inet_frag_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | { |
Pavel Emelyanov | 1e4b828 | 2007-10-15 02:39:14 -0700 | [diff] [blame] | 151 | struct ipq *qp; |
| 152 | |
| 153 | qp = container_of(q, struct ipq, q); |
| 154 | if (qp->peer) |
| 155 | inet_putpeer(qp->peer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | kfree(qp); |
| 157 | } |
| 158 | |
| 159 | static __inline__ struct ipq *frag_alloc_queue(void) |
| 160 | { |
Pavel Emelyanov | e521db9 | 2007-10-17 19:45:23 -0700 | [diff] [blame^] | 161 | struct inet_frag_queue *q; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 162 | |
Pavel Emelyanov | e521db9 | 2007-10-17 19:45:23 -0700 | [diff] [blame^] | 163 | q = inet_frag_alloc(&ip4_frags); |
| 164 | return q ? container_of(q, struct ipq, q) : NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | } |
| 166 | |
| 167 | |
| 168 | /* Destruction primitives. */ |
| 169 | |
Pavel Emelyanov | 4b6cb5d | 2007-10-15 02:41:09 -0700 | [diff] [blame] | 170 | static __inline__ void ipq_put(struct ipq *ipq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | { |
Pavel Emelyanov | 762cc40 | 2007-10-15 02:41:56 -0700 | [diff] [blame] | 172 | inet_frag_put(&ipq->q, &ip4_frags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | } |
| 174 | |
| 175 | /* Kill ipq entry. It is not destroyed immediately, |
| 176 | * because caller (and someone more) holds reference count. |
| 177 | */ |
| 178 | static void ipq_kill(struct ipq *ipq) |
| 179 | { |
Pavel Emelyanov | 277e650 | 2007-10-15 02:37:18 -0700 | [diff] [blame] | 180 | inet_frag_kill(&ipq->q, &ip4_frags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | } |
| 182 | |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 183 | /* Memory limiting on fragments. Evictor trashes the oldest |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | * fragment queue until we are back under the threshold. |
| 185 | */ |
| 186 | static void ip_evictor(void) |
| 187 | { |
Pavel Emelyanov | 8e7999c | 2007-10-15 02:40:06 -0700 | [diff] [blame] | 188 | int evicted; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | |
Pavel Emelyanov | 8e7999c | 2007-10-15 02:40:06 -0700 | [diff] [blame] | 190 | evicted = inet_frag_evictor(&ip4_frags); |
| 191 | if (evicted) |
| 192 | IP_ADD_STATS_BH(IPSTATS_MIB_REASMFAILS, evicted); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | } |
| 194 | |
| 195 | /* |
| 196 | * Oops, a fragment queue timed out. Kill it and send an ICMP reply. |
| 197 | */ |
| 198 | static void ip_expire(unsigned long arg) |
| 199 | { |
Pavel Emelyanov | e521db9 | 2007-10-17 19:45:23 -0700 | [diff] [blame^] | 200 | struct ipq *qp; |
| 201 | |
| 202 | qp = container_of((struct inet_frag_queue *) arg, struct ipq, q); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 204 | spin_lock(&qp->q.lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 206 | if (qp->q.last_in & COMPLETE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 207 | goto out; |
| 208 | |
| 209 | ipq_kill(qp); |
| 210 | |
| 211 | IP_INC_STATS_BH(IPSTATS_MIB_REASMTIMEOUT); |
| 212 | IP_INC_STATS_BH(IPSTATS_MIB_REASMFAILS); |
| 213 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 214 | if ((qp->q.last_in&FIRST_IN) && qp->q.fragments != NULL) { |
| 215 | struct sk_buff *head = qp->q.fragments; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | /* Send an ICMP "Fragment Reassembly Timeout" message. */ |
Eric W. Biederman | 881d966 | 2007-09-17 11:56:21 -0700 | [diff] [blame] | 217 | if ((head->dev = dev_get_by_index(&init_net, qp->iif)) != NULL) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0); |
| 219 | dev_put(head->dev); |
| 220 | } |
| 221 | } |
| 222 | out: |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 223 | spin_unlock(&qp->q.lock); |
Pavel Emelyanov | 4b6cb5d | 2007-10-15 02:41:09 -0700 | [diff] [blame] | 224 | ipq_put(qp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 225 | } |
| 226 | |
| 227 | /* Creation primitives. */ |
| 228 | |
Pavel Emelyanov | fd9e635 | 2007-10-17 19:43:37 -0700 | [diff] [blame] | 229 | static struct ipq *ip_frag_intern(struct ipq *qp_in, unsigned int hash) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | { |
Pavel Emelyanov | 2588fe1 | 2007-10-17 19:44:34 -0700 | [diff] [blame] | 231 | struct inet_frag_queue *q; |
David S. Miller | 55c0022 | 2006-04-09 22:43:55 -0700 | [diff] [blame] | 232 | |
Pavel Emelyanov | 2588fe1 | 2007-10-17 19:44:34 -0700 | [diff] [blame] | 233 | q = inet_frag_intern(&qp_in->q, &ip4_frags, hash); |
| 234 | return container_of(q, struct ipq, q); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | } |
| 236 | |
| 237 | /* Add an entry to the 'ipq' queue for a newly received IP datagram. */ |
Pavel Emelyanov | fd9e635 | 2007-10-17 19:43:37 -0700 | [diff] [blame] | 238 | static struct ipq *ip_frag_create(struct iphdr *iph, u32 user, unsigned int h) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | { |
| 240 | struct ipq *qp; |
| 241 | |
| 242 | if ((qp = frag_alloc_queue()) == NULL) |
| 243 | goto out_nomem; |
| 244 | |
| 245 | qp->protocol = iph->protocol; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | qp->id = iph->id; |
| 247 | qp->saddr = iph->saddr; |
| 248 | qp->daddr = iph->daddr; |
| 249 | qp->user = user; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 250 | qp->peer = sysctl_ipfrag_max_dist ? inet_getpeer(iph->saddr, 1) : NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | |
Pavel Emelyanov | fd9e635 | 2007-10-17 19:43:37 -0700 | [diff] [blame] | 252 | return ip_frag_intern(qp, h); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 253 | |
| 254 | out_nomem: |
Patrick McHardy | 64ce207 | 2005-08-09 20:50:53 -0700 | [diff] [blame] | 255 | LIMIT_NETDEBUG(KERN_ERR "ip_frag_create: no memory left !\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 256 | return NULL; |
| 257 | } |
| 258 | |
| 259 | /* Find the correct entry in the "incomplete datagrams" queue for |
| 260 | * this IP datagram, and create new one, if nothing is found. |
| 261 | */ |
| 262 | static inline struct ipq *ip_find(struct iphdr *iph, u32 user) |
| 263 | { |
Alexey Dobriyan | 76ab608 | 2006-01-06 13:24:29 -0800 | [diff] [blame] | 264 | __be16 id = iph->id; |
Al Viro | 1827777 | 2006-09-26 22:19:02 -0700 | [diff] [blame] | 265 | __be32 saddr = iph->saddr; |
| 266 | __be32 daddr = iph->daddr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 267 | __u8 protocol = iph->protocol; |
David S. Miller | 55c0022 | 2006-04-09 22:43:55 -0700 | [diff] [blame] | 268 | unsigned int hash; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 269 | struct ipq *qp; |
Yasuyuki Kozakai | e7c8a41 | 2005-11-16 12:55:37 -0800 | [diff] [blame] | 270 | struct hlist_node *n; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 272 | read_lock(&ip4_frags.lock); |
David S. Miller | 55c0022 | 2006-04-09 22:43:55 -0700 | [diff] [blame] | 273 | hash = ipqhashfn(id, saddr, daddr, protocol); |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 274 | hlist_for_each_entry(qp, n, &ip4_frags.hash[hash], q.list) { |
Stephen Hemminger | 132adf5 | 2007-03-08 20:44:43 -0800 | [diff] [blame] | 275 | if (qp->id == id && |
| 276 | qp->saddr == saddr && |
| 277 | qp->daddr == daddr && |
| 278 | qp->protocol == protocol && |
| 279 | qp->user == user) { |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 280 | atomic_inc(&qp->q.refcnt); |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 281 | read_unlock(&ip4_frags.lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 282 | return qp; |
| 283 | } |
| 284 | } |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 285 | read_unlock(&ip4_frags.lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | |
Pavel Emelyanov | fd9e635 | 2007-10-17 19:43:37 -0700 | [diff] [blame] | 287 | return ip_frag_create(iph, user, hash); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | } |
| 289 | |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 290 | /* Is the fragment too far ahead to be part of ipq? */ |
| 291 | static inline int ip_frag_too_far(struct ipq *qp) |
| 292 | { |
| 293 | struct inet_peer *peer = qp->peer; |
| 294 | unsigned int max = sysctl_ipfrag_max_dist; |
| 295 | unsigned int start, end; |
| 296 | |
| 297 | int rc; |
| 298 | |
| 299 | if (!peer || !max) |
| 300 | return 0; |
| 301 | |
| 302 | start = qp->rid; |
| 303 | end = atomic_inc_return(&peer->rid); |
| 304 | qp->rid = end; |
| 305 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 306 | rc = qp->q.fragments && (end - start) > max; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 307 | |
| 308 | if (rc) { |
| 309 | IP_INC_STATS_BH(IPSTATS_MIB_REASMFAILS); |
| 310 | } |
| 311 | |
| 312 | return rc; |
| 313 | } |
| 314 | |
| 315 | static int ip_frag_reinit(struct ipq *qp) |
| 316 | { |
| 317 | struct sk_buff *fp; |
| 318 | |
Pavel Emelyanov | 04128f2 | 2007-10-15 02:33:45 -0700 | [diff] [blame] | 319 | if (!mod_timer(&qp->q.timer, jiffies + ip4_frags_ctl.timeout)) { |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 320 | atomic_inc(&qp->q.refcnt); |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 321 | return -ETIMEDOUT; |
| 322 | } |
| 323 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 324 | fp = qp->q.fragments; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 325 | do { |
| 326 | struct sk_buff *xp = fp->next; |
| 327 | frag_kfree_skb(fp, NULL); |
| 328 | fp = xp; |
| 329 | } while (fp); |
| 330 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 331 | qp->q.last_in = 0; |
| 332 | qp->q.len = 0; |
| 333 | qp->q.meat = 0; |
| 334 | qp->q.fragments = NULL; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 335 | qp->iif = 0; |
| 336 | |
| 337 | return 0; |
| 338 | } |
| 339 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | /* Add new segment to existing queue. */ |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 341 | static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | { |
| 343 | struct sk_buff *prev, *next; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 344 | struct net_device *dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 345 | int flags, offset; |
| 346 | int ihl, end; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 347 | int err = -ENOENT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 349 | if (qp->q.last_in & COMPLETE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 350 | goto err; |
| 351 | |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 352 | if (!(IPCB(skb)->flags & IPSKB_FRAG_COMPLETE) && |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 353 | unlikely(ip_frag_too_far(qp)) && |
| 354 | unlikely(err = ip_frag_reinit(qp))) { |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 355 | ipq_kill(qp); |
| 356 | goto err; |
| 357 | } |
| 358 | |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 359 | offset = ntohs(ip_hdr(skb)->frag_off); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | flags = offset & ~IP_OFFSET; |
| 361 | offset &= IP_OFFSET; |
| 362 | offset <<= 3; /* offset is in 8-byte chunks */ |
Arnaldo Carvalho de Melo | c9bdd4b | 2007-03-12 20:09:15 -0300 | [diff] [blame] | 363 | ihl = ip_hdrlen(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 364 | |
| 365 | /* Determine the position of this fragment. */ |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 366 | end = offset + skb->len - ihl; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 367 | err = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | |
| 369 | /* Is this the final fragment? */ |
| 370 | if ((flags & IP_MF) == 0) { |
| 371 | /* If we already have some bits beyond end |
| 372 | * or have different end, the segment is corrrupted. |
| 373 | */ |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 374 | if (end < qp->q.len || |
| 375 | ((qp->q.last_in & LAST_IN) && end != qp->q.len)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 376 | goto err; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 377 | qp->q.last_in |= LAST_IN; |
| 378 | qp->q.len = end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | } else { |
| 380 | if (end&7) { |
| 381 | end &= ~7; |
| 382 | if (skb->ip_summed != CHECKSUM_UNNECESSARY) |
| 383 | skb->ip_summed = CHECKSUM_NONE; |
| 384 | } |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 385 | if (end > qp->q.len) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 386 | /* Some bits beyond end -> corruption. */ |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 387 | if (qp->q.last_in & LAST_IN) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 388 | goto err; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 389 | qp->q.len = end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 390 | } |
| 391 | } |
| 392 | if (end == offset) |
| 393 | goto err; |
| 394 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 395 | err = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | if (pskb_pull(skb, ihl) == NULL) |
| 397 | goto err; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 398 | |
| 399 | err = pskb_trim_rcsum(skb, end - offset); |
| 400 | if (err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 401 | goto err; |
| 402 | |
| 403 | /* Find out which fragments are in front and at the back of us |
| 404 | * in the chain of fragments so far. We must know where to put |
| 405 | * this fragment, right? |
| 406 | */ |
| 407 | prev = NULL; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 408 | for (next = qp->q.fragments; next != NULL; next = next->next) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 409 | if (FRAG_CB(next)->offset >= offset) |
| 410 | break; /* bingo! */ |
| 411 | prev = next; |
| 412 | } |
| 413 | |
| 414 | /* We found where to put this one. Check for overlap with |
| 415 | * preceding fragment, and, if needed, align things so that |
| 416 | * any overlaps are eliminated. |
| 417 | */ |
| 418 | if (prev) { |
| 419 | int i = (FRAG_CB(prev)->offset + prev->len) - offset; |
| 420 | |
| 421 | if (i > 0) { |
| 422 | offset += i; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 423 | err = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 424 | if (end <= offset) |
| 425 | goto err; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 426 | err = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 427 | if (!pskb_pull(skb, i)) |
| 428 | goto err; |
| 429 | if (skb->ip_summed != CHECKSUM_UNNECESSARY) |
| 430 | skb->ip_summed = CHECKSUM_NONE; |
| 431 | } |
| 432 | } |
| 433 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 434 | err = -ENOMEM; |
| 435 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 436 | while (next && FRAG_CB(next)->offset < end) { |
| 437 | int i = end - FRAG_CB(next)->offset; /* overlap is 'i' bytes */ |
| 438 | |
| 439 | if (i < next->len) { |
| 440 | /* Eat head of the next overlapped fragment |
| 441 | * and leave the loop. The next ones cannot overlap. |
| 442 | */ |
| 443 | if (!pskb_pull(next, i)) |
| 444 | goto err; |
| 445 | FRAG_CB(next)->offset += i; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 446 | qp->q.meat -= i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | if (next->ip_summed != CHECKSUM_UNNECESSARY) |
| 448 | next->ip_summed = CHECKSUM_NONE; |
| 449 | break; |
| 450 | } else { |
| 451 | struct sk_buff *free_it = next; |
| 452 | |
Peter Zijlstra | 47c6bf77 | 2006-12-12 19:48:59 +0100 | [diff] [blame] | 453 | /* Old fragment is completely overridden with |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | * new one drop it. |
| 455 | */ |
| 456 | next = next->next; |
| 457 | |
| 458 | if (prev) |
| 459 | prev->next = next; |
| 460 | else |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 461 | qp->q.fragments = next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 463 | qp->q.meat -= free_it->len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | frag_kfree_skb(free_it, NULL); |
| 465 | } |
| 466 | } |
| 467 | |
| 468 | FRAG_CB(skb)->offset = offset; |
| 469 | |
| 470 | /* Insert this fragment in the chain of fragments. */ |
| 471 | skb->next = next; |
| 472 | if (prev) |
| 473 | prev->next = skb; |
| 474 | else |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 475 | qp->q.fragments = skb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 476 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 477 | dev = skb->dev; |
| 478 | if (dev) { |
| 479 | qp->iif = dev->ifindex; |
| 480 | skb->dev = NULL; |
| 481 | } |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 482 | qp->q.stamp = skb->tstamp; |
| 483 | qp->q.meat += skb->len; |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 484 | atomic_add(skb->truesize, &ip4_frags.mem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 485 | if (offset == 0) |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 486 | qp->q.last_in |= FIRST_IN; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 487 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 488 | if (qp->q.last_in == (FIRST_IN | LAST_IN) && qp->q.meat == qp->q.len) |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 489 | return ip_frag_reasm(qp, prev, dev); |
| 490 | |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 491 | write_lock(&ip4_frags.lock); |
| 492 | list_move_tail(&qp->q.lru_list, &ip4_frags.lru_list); |
| 493 | write_unlock(&ip4_frags.lock); |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 494 | return -EINPROGRESS; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 495 | |
| 496 | err: |
| 497 | kfree_skb(skb); |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 498 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | } |
| 500 | |
| 501 | |
| 502 | /* Build a new IP datagram from all its fragments. */ |
| 503 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 504 | static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, |
| 505 | struct net_device *dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | { |
| 507 | struct iphdr *iph; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 508 | struct sk_buff *fp, *head = qp->q.fragments; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 509 | int len; |
| 510 | int ihlen; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 511 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 512 | |
| 513 | ipq_kill(qp); |
| 514 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 515 | /* Make the one we just received the head. */ |
| 516 | if (prev) { |
| 517 | head = prev->next; |
| 518 | fp = skb_clone(head, GFP_ATOMIC); |
| 519 | |
| 520 | if (!fp) |
| 521 | goto out_nomem; |
| 522 | |
| 523 | fp->next = head->next; |
| 524 | prev->next = fp; |
| 525 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 526 | skb_morph(head, qp->q.fragments); |
| 527 | head->next = qp->q.fragments->next; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 528 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 529 | kfree_skb(qp->q.fragments); |
| 530 | qp->q.fragments = head; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 531 | } |
| 532 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 533 | BUG_TRAP(head != NULL); |
| 534 | BUG_TRAP(FRAG_CB(head)->offset == 0); |
| 535 | |
| 536 | /* Allocate a new buffer for the datagram. */ |
Arnaldo Carvalho de Melo | c9bdd4b | 2007-03-12 20:09:15 -0300 | [diff] [blame] | 537 | ihlen = ip_hdrlen(head); |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 538 | len = ihlen + qp->q.len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 539 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 540 | err = -E2BIG; |
Stephen Hemminger | 132adf5 | 2007-03-08 20:44:43 -0800 | [diff] [blame] | 541 | if (len > 65535) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 542 | goto out_oversize; |
| 543 | |
| 544 | /* Head of list must not be cloned. */ |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 545 | err = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 546 | if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) |
| 547 | goto out_nomem; |
| 548 | |
| 549 | /* If the first fragment is fragmented itself, we split |
| 550 | * it to two chunks: the first with data and paged part |
| 551 | * and the second, holding only fragments. */ |
| 552 | if (skb_shinfo(head)->frag_list) { |
| 553 | struct sk_buff *clone; |
| 554 | int i, plen = 0; |
| 555 | |
| 556 | if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) |
| 557 | goto out_nomem; |
| 558 | clone->next = head->next; |
| 559 | head->next = clone; |
| 560 | skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; |
| 561 | skb_shinfo(head)->frag_list = NULL; |
| 562 | for (i=0; i<skb_shinfo(head)->nr_frags; i++) |
| 563 | plen += skb_shinfo(head)->frags[i].size; |
| 564 | clone->len = clone->data_len = head->data_len - plen; |
| 565 | head->data_len -= clone->len; |
| 566 | head->len -= clone->len; |
| 567 | clone->csum = 0; |
| 568 | clone->ip_summed = head->ip_summed; |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 569 | atomic_add(clone->truesize, &ip4_frags.mem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | } |
| 571 | |
| 572 | skb_shinfo(head)->frag_list = head->next; |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 573 | skb_push(head, head->data - skb_network_header(head)); |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 574 | atomic_sub(head->truesize, &ip4_frags.mem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 575 | |
| 576 | for (fp=head->next; fp; fp = fp->next) { |
| 577 | head->data_len += fp->len; |
| 578 | head->len += fp->len; |
| 579 | if (head->ip_summed != fp->ip_summed) |
| 580 | head->ip_summed = CHECKSUM_NONE; |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 581 | else if (head->ip_summed == CHECKSUM_COMPLETE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 582 | head->csum = csum_add(head->csum, fp->csum); |
| 583 | head->truesize += fp->truesize; |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 584 | atomic_sub(fp->truesize, &ip4_frags.mem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 585 | } |
| 586 | |
| 587 | head->next = NULL; |
| 588 | head->dev = dev; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 589 | head->tstamp = qp->q.stamp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 590 | |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 591 | iph = ip_hdr(head); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 592 | iph->frag_off = 0; |
| 593 | iph->tot_len = htons(len); |
| 594 | IP_INC_STATS_BH(IPSTATS_MIB_REASMOKS); |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 595 | qp->q.fragments = NULL; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 596 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 597 | |
| 598 | out_nomem: |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 599 | LIMIT_NETDEBUG(KERN_ERR "IP: queue_glue: no memory for gluing " |
Patrick McHardy | 64ce207 | 2005-08-09 20:50:53 -0700 | [diff] [blame] | 600 | "queue %p\n", qp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 601 | goto out_fail; |
| 602 | out_oversize: |
| 603 | if (net_ratelimit()) |
| 604 | printk(KERN_INFO |
| 605 | "Oversized IP packet from %d.%d.%d.%d.\n", |
| 606 | NIPQUAD(qp->saddr)); |
| 607 | out_fail: |
| 608 | IP_INC_STATS_BH(IPSTATS_MIB_REASMFAILS); |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 609 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 610 | } |
| 611 | |
| 612 | /* Process an incoming IP datagram fragment. */ |
Herbert Xu | 776c729 | 2007-10-14 00:38:32 -0700 | [diff] [blame] | 613 | int ip_defrag(struct sk_buff *skb, u32 user) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 614 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | struct ipq *qp; |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 616 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 617 | IP_INC_STATS_BH(IPSTATS_MIB_REASMREQDS); |
| 618 | |
| 619 | /* Start by cleaning up the memory. */ |
Pavel Emelyanov | 04128f2 | 2007-10-15 02:33:45 -0700 | [diff] [blame] | 620 | if (atomic_read(&ip4_frags.mem) > ip4_frags_ctl.high_thresh) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | ip_evictor(); |
| 622 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | /* Lookup (or create) queue header */ |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 624 | if ((qp = ip_find(ip_hdr(skb), user)) != NULL) { |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 625 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 626 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 627 | spin_lock(&qp->q.lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 628 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 629 | ret = ip_frag_queue(qp, skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 630 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 631 | spin_unlock(&qp->q.lock); |
Pavel Emelyanov | 4b6cb5d | 2007-10-15 02:41:09 -0700 | [diff] [blame] | 632 | ipq_put(qp); |
Herbert Xu | 776c729 | 2007-10-14 00:38:32 -0700 | [diff] [blame] | 633 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 634 | } |
| 635 | |
| 636 | IP_INC_STATS_BH(IPSTATS_MIB_REASMFAILS); |
| 637 | kfree_skb(skb); |
Herbert Xu | 776c729 | 2007-10-14 00:38:32 -0700 | [diff] [blame] | 638 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 639 | } |
| 640 | |
Eric Dumazet | b7aa0bf | 2007-04-19 16:16:32 -0700 | [diff] [blame] | 641 | void __init ipfrag_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 642 | { |
Pavel Emelyanov | 04128f2 | 2007-10-15 02:33:45 -0700 | [diff] [blame] | 643 | ip4_frags.ctl = &ip4_frags_ctl; |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 644 | ip4_frags.hashfn = ip4_hashfn; |
Pavel Emelyanov | 1e4b828 | 2007-10-15 02:39:14 -0700 | [diff] [blame] | 645 | ip4_frags.destructor = ip4_frag_free; |
| 646 | ip4_frags.skb_free = NULL; |
| 647 | ip4_frags.qsize = sizeof(struct ipq); |
Pavel Emelyanov | 2588fe1 | 2007-10-17 19:44:34 -0700 | [diff] [blame] | 648 | ip4_frags.equal = ip4_frag_equal; |
Pavel Emelyanov | e521db9 | 2007-10-17 19:45:23 -0700 | [diff] [blame^] | 649 | ip4_frags.frag_expire = ip_expire; |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 650 | inet_frags_init(&ip4_frags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 651 | } |
| 652 | |
| 653 | EXPORT_SYMBOL(ip_defrag); |