Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * IPv6 fragment reassembly | |
1ab1457c | 3 | * Linux INET6 implementation |
1da177e4 LT |
4 | * |
5 | * Authors: | |
1ab1457c | 6 | * Pedro Roque <roque@di.fc.ul.pt> |
1da177e4 | 7 | * |
1da177e4 LT |
8 | * Based on: net/ipv4/ip_fragment.c |
9 | * | |
10 | * This program is free software; you can redistribute it and/or | |
11 | * modify it under the terms of the GNU General Public License | |
12 | * as published by the Free Software Foundation; either version | |
13 | * 2 of the License, or (at your option) any later version. | |
14 | */ | |
15 | ||
1ab1457c YH |
16 | /* |
17 | * Fixes: | |
1da177e4 LT |
18 | * Andi Kleen Make it work with multiple hosts. |
19 | * More RFC compliance. | |
20 | * | |
21 | * Horst von Brand Add missing #include <linux/string.h> | |
22 | * Alexey Kuznetsov SMP races, threading, cleanup. | |
23 | * Patrick McHardy LRU queue of frag heads for evictor. | |
24 | * Mitsuru KANDA @USAGI Register inet6_protocol{}. | |
25 | * David Stevens and | |
26 | * YOSHIFUJI,H. @USAGI Always remove fragment header to | |
27 | * calculate ICV correctly. | |
28 | */ | |
1da177e4 LT |
29 | #include <linux/errno.h> |
30 | #include <linux/types.h> | |
31 | #include <linux/string.h> | |
32 | #include <linux/socket.h> | |
33 | #include <linux/sockios.h> | |
34 | #include <linux/jiffies.h> | |
35 | #include <linux/net.h> | |
36 | #include <linux/list.h> | |
37 | #include <linux/netdevice.h> | |
38 | #include <linux/in6.h> | |
39 | #include <linux/ipv6.h> | |
40 | #include <linux/icmpv6.h> | |
41 | #include <linux/random.h> | |
42 | #include <linux/jhash.h> | |
f61944ef | 43 | #include <linux/skbuff.h> |
5a0e3ad6 | 44 | #include <linux/slab.h> |
bc3b2d7f | 45 | #include <linux/export.h> |
1da177e4 LT |
46 | |
47 | #include <net/sock.h> | |
48 | #include <net/snmp.h> | |
49 | ||
50 | #include <net/ipv6.h> | |
a11d206d | 51 | #include <net/ip6_route.h> |
1da177e4 LT |
52 | #include <net/protocol.h> |
53 | #include <net/transp_v6.h> | |
54 | #include <net/rawv6.h> | |
55 | #include <net/ndisc.h> | |
56 | #include <net/addrconf.h> | |
5ab11c98 | 57 | #include <net/inet_frag.h> |
1da177e4 | 58 | |
1da177e4 LT |
59 | struct ip6frag_skb_cb |
60 | { | |
61 | struct inet6_skb_parm h; | |
62 | int offset; | |
63 | }; | |
64 | ||
65 | #define FRAG6_CB(skb) ((struct ip6frag_skb_cb*)((skb)->cb)) | |
66 | ||
67 | ||
68 | /* | |
69 | * Equivalent of ipv4 struct ipq | |
70 | */ | |
71 | ||
72 | struct frag_queue | |
73 | { | |
5ab11c98 | 74 | struct inet_frag_queue q; |
1da177e4 | 75 | |
e69a4adc | 76 | __be32 id; /* fragment id */ |
0b5ccb2e | 77 | u32 user; |
1da177e4 LT |
78 | struct in6_addr saddr; |
79 | struct in6_addr daddr; | |
80 | ||
1da177e4 | 81 | int iif; |
1da177e4 | 82 | unsigned int csum; |
1da177e4 | 83 | __u16 nhoffset; |
1da177e4 LT |
84 | }; |
85 | ||
7eb95156 | 86 | static struct inet_frags ip6_frags; |
1da177e4 | 87 | |
e5a2bb84 | 88 | int ip6_frag_nqueues(struct net *net) |
7eb95156 | 89 | { |
e5a2bb84 | 90 | return net->ipv6.frags.nqueues; |
7eb95156 | 91 | } |
1da177e4 | 92 | |
6ddc0822 | 93 | int ip6_frag_mem(struct net *net) |
7eb95156 | 94 | { |
6ddc0822 | 95 | return atomic_read(&net->ipv6.frags.mem); |
7eb95156 | 96 | } |
1da177e4 | 97 | |
f61944ef HX |
98 | static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev, |
99 | struct net_device *dev); | |
100 | ||
f6596f9d ZB |
101 | /* |
102 | * callers should be careful not to use the hash value outside the ipfrag_lock | |
103 | * as doing so could race with ipfrag_hash_rnd being recalculated. | |
104 | */ | |
93c8b90f IJ |
105 | unsigned int inet6_hash_frag(__be32 id, const struct in6_addr *saddr, |
106 | const struct in6_addr *daddr, u32 rnd) | |
1da177e4 | 107 | { |
82a39eb6 JK |
108 | u32 c; |
109 | ||
110 | c = jhash_3words((__force u32)saddr->s6_addr32[0], | |
111 | (__force u32)saddr->s6_addr32[1], | |
112 | (__force u32)saddr->s6_addr32[2], | |
113 | rnd); | |
114 | ||
115 | c = jhash_3words((__force u32)saddr->s6_addr32[3], | |
116 | (__force u32)daddr->s6_addr32[0], | |
117 | (__force u32)daddr->s6_addr32[1], | |
118 | c); | |
119 | ||
120 | c = jhash_3words((__force u32)daddr->s6_addr32[2], | |
121 | (__force u32)daddr->s6_addr32[3], | |
122 | (__force u32)id, | |
123 | c); | |
1da177e4 | 124 | |
7eb95156 | 125 | return c & (INETFRAGS_HASHSZ - 1); |
1da177e4 | 126 | } |
93c8b90f | 127 | EXPORT_SYMBOL_GPL(inet6_hash_frag); |
1da177e4 | 128 | |
321a3a99 | 129 | static unsigned int ip6_hashfn(struct inet_frag_queue *q) |
1da177e4 | 130 | { |
321a3a99 | 131 | struct frag_queue *fq; |
1da177e4 | 132 | |
321a3a99 | 133 | fq = container_of(q, struct frag_queue, q); |
93c8b90f | 134 | return inet6_hash_frag(fq->id, &fq->saddr, &fq->daddr, ip6_frags.rnd); |
1da177e4 LT |
135 | } |
136 | ||
cbc264ca | 137 | bool ip6_frag_match(struct inet_frag_queue *q, void *a) |
abd6523d PE |
138 | { |
139 | struct frag_queue *fq; | |
140 | struct ip6_create_arg *arg = a; | |
141 | ||
142 | fq = container_of(q, struct frag_queue, q); | |
cbc264ca ED |
143 | return fq->id == arg->id && |
144 | fq->user == arg->user && | |
145 | ipv6_addr_equal(&fq->saddr, arg->src) && | |
146 | ipv6_addr_equal(&fq->daddr, arg->dst); | |
abd6523d PE |
147 | } |
148 | EXPORT_SYMBOL(ip6_frag_match); | |
149 | ||
c6fda282 | 150 | void ip6_frag_init(struct inet_frag_queue *q, void *a) |
1da177e4 | 151 | { |
c6fda282 PE |
152 | struct frag_queue *fq = container_of(q, struct frag_queue, q); |
153 | struct ip6_create_arg *arg = a; | |
154 | ||
155 | fq->id = arg->id; | |
0b5ccb2e | 156 | fq->user = arg->user; |
4e3fd7a0 AD |
157 | fq->saddr = *arg->src; |
158 | fq->daddr = *arg->dst; | |
1da177e4 | 159 | } |
c6fda282 | 160 | EXPORT_SYMBOL(ip6_frag_init); |
1da177e4 | 161 | |
1da177e4 LT |
162 | /* Destruction primitives. */ |
163 | ||
4b6cb5d8 | 164 | static __inline__ void fq_put(struct frag_queue *fq) |
1da177e4 | 165 | { |
762cc408 | 166 | inet_frag_put(&fq->q, &ip6_frags); |
1da177e4 LT |
167 | } |
168 | ||
169 | /* Kill fq entry. It is not destroyed immediately, | |
170 | * because caller (and someone more) holds reference count. | |
171 | */ | |
172 | static __inline__ void fq_kill(struct frag_queue *fq) | |
173 | { | |
277e650d | 174 | inet_frag_kill(&fq->q, &ip6_frags); |
1da177e4 LT |
175 | } |
176 | ||
6ddc0822 | 177 | static void ip6_evictor(struct net *net, struct inet6_dev *idev) |
1da177e4 | 178 | { |
8e7999c4 PE |
179 | int evicted; |
180 | ||
6ddc0822 | 181 | evicted = inet_frag_evictor(&net->ipv6.frags, &ip6_frags); |
8e7999c4 | 182 | if (evicted) |
821d5777 | 183 | IP6_ADD_STATS_BH(net, idev, IPSTATS_MIB_REASMFAILS, evicted); |
1da177e4 LT |
184 | } |
185 | ||
186 | static void ip6_frag_expire(unsigned long data) | |
187 | { | |
e521db9d | 188 | struct frag_queue *fq; |
a11d206d | 189 | struct net_device *dev = NULL; |
4ac2ccd0 | 190 | struct net *net; |
1da177e4 | 191 | |
e521db9d PE |
192 | fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q); |
193 | ||
5ab11c98 | 194 | spin_lock(&fq->q.lock); |
1da177e4 | 195 | |
bc578a54 | 196 | if (fq->q.last_in & INET_FRAG_COMPLETE) |
1da177e4 LT |
197 | goto out; |
198 | ||
199 | fq_kill(fq); | |
200 | ||
4ac2ccd0 | 201 | net = container_of(fq->q.net, struct net, ipv6.frags); |
69df9d59 ED |
202 | rcu_read_lock(); |
203 | dev = dev_get_by_index_rcu(net, fq->iif); | |
a11d206d | 204 | if (!dev) |
69df9d59 | 205 | goto out_rcu_unlock; |
a11d206d | 206 | |
483a47d2 DL |
207 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT); |
208 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS); | |
1da177e4 | 209 | |
78c784c4 | 210 | /* Don't send error if the first segment did not arrive. */ |
bc578a54 | 211 | if (!(fq->q.last_in & INET_FRAG_FIRST_IN) || !fq->q.fragments) |
69df9d59 | 212 | goto out_rcu_unlock; |
78c784c4 | 213 | |
78c784c4 IO |
214 | /* |
215 | But use as source device on which LAST ARRIVED | |
216 | segment was received. And do not use fq->dev | |
217 | pointer directly, device might already disappeared. | |
218 | */ | |
5ab11c98 | 219 | fq->q.fragments->dev = dev; |
3ffe533c | 220 | icmpv6_send(fq->q.fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0); |
69df9d59 ED |
221 | out_rcu_unlock: |
222 | rcu_read_unlock(); | |
1da177e4 | 223 | out: |
5ab11c98 | 224 | spin_unlock(&fq->q.lock); |
4b6cb5d8 | 225 | fq_put(fq); |
1da177e4 LT |
226 | } |
227 | ||
abd6523d | 228 | static __inline__ struct frag_queue * |
b71d1d42 | 229 | fq_find(struct net *net, __be32 id, const struct in6_addr *src, const struct in6_addr *dst) |
1da177e4 | 230 | { |
c6fda282 PE |
231 | struct inet_frag_queue *q; |
232 | struct ip6_create_arg arg; | |
abd6523d | 233 | unsigned int hash; |
1da177e4 | 234 | |
c6fda282 | 235 | arg.id = id; |
0b5ccb2e | 236 | arg.user = IP6_DEFRAG_LOCAL_DELIVER; |
c6fda282 PE |
237 | arg.src = src; |
238 | arg.dst = dst; | |
9a375803 PE |
239 | |
240 | read_lock(&ip6_frags.lock); | |
93c8b90f | 241 | hash = inet6_hash_frag(id, src, dst, ip6_frags.rnd); |
1da177e4 | 242 | |
ac18e750 | 243 | q = inet_frag_find(&net->ipv6.frags, &ip6_frags, &arg, hash); |
c6fda282 | 244 | if (q == NULL) |
9546377c | 245 | return NULL; |
1da177e4 | 246 | |
c6fda282 | 247 | return container_of(q, struct frag_queue, q); |
1da177e4 LT |
248 | } |
249 | ||
f61944ef | 250 | static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, |
1da177e4 LT |
251 | struct frag_hdr *fhdr, int nhoff) |
252 | { | |
253 | struct sk_buff *prev, *next; | |
f61944ef | 254 | struct net_device *dev; |
1da177e4 | 255 | int offset, end; |
adf30907 | 256 | struct net *net = dev_net(skb_dst(skb)->dev); |
1da177e4 | 257 | |
bc578a54 | 258 | if (fq->q.last_in & INET_FRAG_COMPLETE) |
1da177e4 LT |
259 | goto err; |
260 | ||
261 | offset = ntohs(fhdr->frag_off) & ~0x7; | |
0660e03f ACM |
262 | end = offset + (ntohs(ipv6_hdr(skb)->payload_len) - |
263 | ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1))); | |
1da177e4 LT |
264 | |
265 | if ((unsigned int)end > IPV6_MAXPLEN) { | |
adf30907 | 266 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 267 | IPSTATS_MIB_INHDRERRORS); |
d56f90a7 ACM |
268 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
269 | ((u8 *)&fhdr->frag_off - | |
270 | skb_network_header(skb))); | |
f61944ef | 271 | return -1; |
1da177e4 LT |
272 | } |
273 | ||
d56f90a7 ACM |
274 | if (skb->ip_summed == CHECKSUM_COMPLETE) { |
275 | const unsigned char *nh = skb_network_header(skb); | |
1ab1457c | 276 | skb->csum = csum_sub(skb->csum, |
d56f90a7 ACM |
277 | csum_partial(nh, (u8 *)(fhdr + 1) - nh, |
278 | 0)); | |
279 | } | |
1da177e4 LT |
280 | |
281 | /* Is this the final fragment? */ | |
282 | if (!(fhdr->frag_off & htons(IP6_MF))) { | |
283 | /* If we already have some bits beyond end | |
284 | * or have different end, the segment is corrupted. | |
285 | */ | |
5ab11c98 | 286 | if (end < fq->q.len || |
bc578a54 | 287 | ((fq->q.last_in & INET_FRAG_LAST_IN) && end != fq->q.len)) |
1da177e4 | 288 | goto err; |
bc578a54 | 289 | fq->q.last_in |= INET_FRAG_LAST_IN; |
5ab11c98 | 290 | fq->q.len = end; |
1da177e4 LT |
291 | } else { |
292 | /* Check if the fragment is rounded to 8 bytes. | |
293 | * Required by the RFC. | |
294 | */ | |
295 | if (end & 0x7) { | |
296 | /* RFC2460 says always send parameter problem in | |
297 | * this case. -DaveM | |
298 | */ | |
adf30907 | 299 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 300 | IPSTATS_MIB_INHDRERRORS); |
1ab1457c | 301 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
1da177e4 | 302 | offsetof(struct ipv6hdr, payload_len)); |
f61944ef | 303 | return -1; |
1da177e4 | 304 | } |
5ab11c98 | 305 | if (end > fq->q.len) { |
1da177e4 | 306 | /* Some bits beyond end -> corruption. */ |
bc578a54 | 307 | if (fq->q.last_in & INET_FRAG_LAST_IN) |
1da177e4 | 308 | goto err; |
5ab11c98 | 309 | fq->q.len = end; |
1da177e4 LT |
310 | } |
311 | } | |
312 | ||
313 | if (end == offset) | |
314 | goto err; | |
315 | ||
316 | /* Point into the IP datagram 'data' part. */ | |
317 | if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) | |
318 | goto err; | |
1ab1457c | 319 | |
42ca89c1 SH |
320 | if (pskb_trim_rcsum(skb, end - offset)) |
321 | goto err; | |
1da177e4 LT |
322 | |
323 | /* Find out which fragments are in front and at the back of us | |
324 | * in the chain of fragments so far. We must know where to put | |
325 | * this fragment, right? | |
326 | */ | |
d6bebca9 CG |
327 | prev = fq->q.fragments_tail; |
328 | if (!prev || FRAG6_CB(prev)->offset < offset) { | |
329 | next = NULL; | |
330 | goto found; | |
331 | } | |
1da177e4 | 332 | prev = NULL; |
5ab11c98 | 333 | for(next = fq->q.fragments; next != NULL; next = next->next) { |
1da177e4 LT |
334 | if (FRAG6_CB(next)->offset >= offset) |
335 | break; /* bingo! */ | |
336 | prev = next; | |
337 | } | |
338 | ||
d6bebca9 | 339 | found: |
5de658f8 ED |
340 | /* RFC5722, Section 4, amended by Errata ID : 3089 |
341 | * When reassembling an IPv6 datagram, if | |
70789d70 ND |
342 | * one or more its constituent fragments is determined to be an |
343 | * overlapping fragment, the entire datagram (and any constituent | |
5de658f8 | 344 | * fragments) MUST be silently discarded. |
1da177e4 | 345 | */ |
1da177e4 | 346 | |
70789d70 ND |
347 | /* Check for overlap with preceding fragment. */ |
348 | if (prev && | |
f4642141 | 349 | (FRAG6_CB(prev)->offset + prev->len) > offset) |
70789d70 | 350 | goto discard_fq; |
1da177e4 | 351 | |
70789d70 ND |
352 | /* Look for overlap with succeeding segment. */ |
353 | if (next && FRAG6_CB(next)->offset < end) | |
354 | goto discard_fq; | |
1da177e4 LT |
355 | |
356 | FRAG6_CB(skb)->offset = offset; | |
357 | ||
358 | /* Insert this fragment in the chain of fragments. */ | |
359 | skb->next = next; | |
d6bebca9 CG |
360 | if (!next) |
361 | fq->q.fragments_tail = skb; | |
1da177e4 LT |
362 | if (prev) |
363 | prev->next = skb; | |
364 | else | |
5ab11c98 | 365 | fq->q.fragments = skb; |
1da177e4 | 366 | |
f61944ef HX |
367 | dev = skb->dev; |
368 | if (dev) { | |
369 | fq->iif = dev->ifindex; | |
370 | skb->dev = NULL; | |
371 | } | |
5ab11c98 PE |
372 | fq->q.stamp = skb->tstamp; |
373 | fq->q.meat += skb->len; | |
6ddc0822 | 374 | atomic_add(skb->truesize, &fq->q.net->mem); |
1da177e4 LT |
375 | |
376 | /* The first fragment. | |
377 | * nhoffset is obtained from the first fragment, of course. | |
378 | */ | |
379 | if (offset == 0) { | |
380 | fq->nhoffset = nhoff; | |
bc578a54 | 381 | fq->q.last_in |= INET_FRAG_FIRST_IN; |
1da177e4 | 382 | } |
f61944ef | 383 | |
bc578a54 JP |
384 | if (fq->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && |
385 | fq->q.meat == fq->q.len) | |
f61944ef HX |
386 | return ip6_frag_reasm(fq, prev, dev); |
387 | ||
7eb95156 | 388 | write_lock(&ip6_frags.lock); |
3140c25c | 389 | list_move_tail(&fq->q.lru_list, &fq->q.net->lru_list); |
7eb95156 | 390 | write_unlock(&ip6_frags.lock); |
f61944ef | 391 | return -1; |
1da177e4 | 392 | |
70789d70 ND |
393 | discard_fq: |
394 | fq_kill(fq); | |
1da177e4 | 395 | err: |
adf30907 | 396 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
3bd653c8 | 397 | IPSTATS_MIB_REASMFAILS); |
1da177e4 | 398 | kfree_skb(skb); |
f61944ef | 399 | return -1; |
1da177e4 LT |
400 | } |
401 | ||
402 | /* | |
403 | * Check if this packet is complete. | |
404 | * Returns NULL on failure by any reason, and pointer | |
405 | * to current nexthdr field in reassembled frame. | |
406 | * | |
407 | * It is called with locked fq, and caller must check that | |
408 | * queue is eligible for reassembly i.e. it is not COMPLETE, | |
409 | * the last and the first frames arrived and all the bits are here. | |
410 | */ | |
f61944ef | 411 | static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev, |
1da177e4 LT |
412 | struct net_device *dev) |
413 | { | |
2bad35b7 | 414 | struct net *net = container_of(fq->q.net, struct net, ipv6.frags); |
5ab11c98 | 415 | struct sk_buff *fp, *head = fq->q.fragments; |
1da177e4 LT |
416 | int payload_len; |
417 | unsigned int nhoff; | |
418 | ||
419 | fq_kill(fq); | |
420 | ||
f61944ef HX |
421 | /* Make the one we just received the head. */ |
422 | if (prev) { | |
423 | head = prev->next; | |
424 | fp = skb_clone(head, GFP_ATOMIC); | |
425 | ||
426 | if (!fp) | |
427 | goto out_oom; | |
428 | ||
429 | fp->next = head->next; | |
d6bebca9 CG |
430 | if (!fp->next) |
431 | fq->q.fragments_tail = fp; | |
f61944ef HX |
432 | prev->next = fp; |
433 | ||
5ab11c98 PE |
434 | skb_morph(head, fq->q.fragments); |
435 | head->next = fq->q.fragments->next; | |
f61944ef | 436 | |
808db80a | 437 | consume_skb(fq->q.fragments); |
5ab11c98 | 438 | fq->q.fragments = head; |
f61944ef HX |
439 | } |
440 | ||
547b792c IJ |
441 | WARN_ON(head == NULL); |
442 | WARN_ON(FRAG6_CB(head)->offset != 0); | |
1da177e4 LT |
443 | |
444 | /* Unfragmented part is taken from the first segment. */ | |
d56f90a7 | 445 | payload_len = ((head->data - skb_network_header(head)) - |
5ab11c98 | 446 | sizeof(struct ipv6hdr) + fq->q.len - |
d56f90a7 | 447 | sizeof(struct frag_hdr)); |
1da177e4 LT |
448 | if (payload_len > IPV6_MAXPLEN) |
449 | goto out_oversize; | |
450 | ||
451 | /* Head of list must not be cloned. */ | |
452 | if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) | |
453 | goto out_oom; | |
454 | ||
455 | /* If the first fragment is fragmented itself, we split | |
456 | * it to two chunks: the first with data and paged part | |
457 | * and the second, holding only fragments. */ | |
21dc3301 | 458 | if (skb_has_frag_list(head)) { |
1da177e4 LT |
459 | struct sk_buff *clone; |
460 | int i, plen = 0; | |
461 | ||
462 | if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) | |
463 | goto out_oom; | |
464 | clone->next = head->next; | |
465 | head->next = clone; | |
466 | skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; | |
4d9092bb | 467 | skb_frag_list_init(head); |
9e903e08 ED |
468 | for (i = 0; i < skb_shinfo(head)->nr_frags; i++) |
469 | plen += skb_frag_size(&skb_shinfo(head)->frags[i]); | |
1da177e4 LT |
470 | clone->len = clone->data_len = head->data_len - plen; |
471 | head->data_len -= clone->len; | |
472 | head->len -= clone->len; | |
473 | clone->csum = 0; | |
474 | clone->ip_summed = head->ip_summed; | |
6ddc0822 | 475 | atomic_add(clone->truesize, &fq->q.net->mem); |
1da177e4 LT |
476 | } |
477 | ||
478 | /* We have to remove fragment header from datagram and to relocate | |
479 | * header in order to calculate ICV correctly. */ | |
480 | nhoff = fq->nhoffset; | |
b0e380b1 | 481 | skb_network_header(head)[nhoff] = skb_transport_header(head)[0]; |
1ab1457c | 482 | memmove(head->head + sizeof(struct frag_hdr), head->head, |
1da177e4 | 483 | (head->data - head->head) - sizeof(struct frag_hdr)); |
b0e380b1 ACM |
484 | head->mac_header += sizeof(struct frag_hdr); |
485 | head->network_header += sizeof(struct frag_hdr); | |
1da177e4 LT |
486 | |
487 | skb_shinfo(head)->frag_list = head->next; | |
badff6d0 | 488 | skb_reset_transport_header(head); |
d56f90a7 | 489 | skb_push(head, head->data - skb_network_header(head)); |
1da177e4 LT |
490 | |
491 | for (fp=head->next; fp; fp = fp->next) { | |
492 | head->data_len += fp->len; | |
493 | head->len += fp->len; | |
494 | if (head->ip_summed != fp->ip_summed) | |
495 | head->ip_summed = CHECKSUM_NONE; | |
84fa7933 | 496 | else if (head->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
497 | head->csum = csum_add(head->csum, fp->csum); |
498 | head->truesize += fp->truesize; | |
1da177e4 | 499 | } |
d27f9b35 | 500 | atomic_sub(head->truesize, &fq->q.net->mem); |
1da177e4 LT |
501 | |
502 | head->next = NULL; | |
503 | head->dev = dev; | |
5ab11c98 | 504 | head->tstamp = fq->q.stamp; |
0660e03f | 505 | ipv6_hdr(head)->payload_len = htons(payload_len); |
951dbc8a | 506 | IP6CB(head)->nhoff = nhoff; |
1da177e4 | 507 | |
1da177e4 | 508 | /* Yes, and fold redundant checksum back. 8) */ |
84fa7933 | 509 | if (head->ip_summed == CHECKSUM_COMPLETE) |
d56f90a7 | 510 | head->csum = csum_partial(skb_network_header(head), |
cfe1fc77 | 511 | skb_network_header_len(head), |
d56f90a7 | 512 | head->csum); |
1da177e4 | 513 | |
a11d206d | 514 | rcu_read_lock(); |
2bad35b7 | 515 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMOKS); |
a11d206d | 516 | rcu_read_unlock(); |
5ab11c98 | 517 | fq->q.fragments = NULL; |
d6bebca9 | 518 | fq->q.fragments_tail = NULL; |
1da177e4 LT |
519 | return 1; |
520 | ||
521 | out_oversize: | |
e87cc472 | 522 | net_dbg_ratelimited("ip6_frag_reasm: payload len = %d\n", payload_len); |
1da177e4 LT |
523 | goto out_fail; |
524 | out_oom: | |
e87cc472 | 525 | net_dbg_ratelimited("ip6_frag_reasm: no memory for reassembly\n"); |
1da177e4 | 526 | out_fail: |
a11d206d | 527 | rcu_read_lock(); |
2bad35b7 | 528 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS); |
a11d206d | 529 | rcu_read_unlock(); |
1da177e4 LT |
530 | return -1; |
531 | } | |
532 | ||
e5bbef20 | 533 | static int ipv6_frag_rcv(struct sk_buff *skb) |
1da177e4 | 534 | { |
1da177e4 LT |
535 | struct frag_hdr *fhdr; |
536 | struct frag_queue *fq; | |
b71d1d42 | 537 | const struct ipv6hdr *hdr = ipv6_hdr(skb); |
adf30907 | 538 | struct net *net = dev_net(skb_dst(skb)->dev); |
1da177e4 | 539 | |
adf30907 | 540 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMREQDS); |
1da177e4 LT |
541 | |
542 | /* Jumbo payload inhibits frag. header */ | |
98b3377c DL |
543 | if (hdr->payload_len==0) |
544 | goto fail_hdr; | |
545 | ||
ea2ae17d | 546 | if (!pskb_may_pull(skb, (skb_transport_offset(skb) + |
98b3377c DL |
547 | sizeof(struct frag_hdr)))) |
548 | goto fail_hdr; | |
1da177e4 | 549 | |
0660e03f | 550 | hdr = ipv6_hdr(skb); |
9c70220b | 551 | fhdr = (struct frag_hdr *)skb_transport_header(skb); |
1da177e4 LT |
552 | |
553 | if (!(fhdr->frag_off & htons(0xFFF9))) { | |
554 | /* It is not a fragmented frame */ | |
b0e380b1 | 555 | skb->transport_header += sizeof(struct frag_hdr); |
483a47d2 | 556 | IP6_INC_STATS_BH(net, |
adf30907 | 557 | ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMOKS); |
1da177e4 | 558 | |
d56f90a7 | 559 | IP6CB(skb)->nhoff = (u8 *)fhdr - skb_network_header(skb); |
1da177e4 LT |
560 | return 1; |
561 | } | |
562 | ||
e31e0bdc | 563 | if (atomic_read(&net->ipv6.frags.mem) > net->ipv6.frags.high_thresh) |
adf30907 | 564 | ip6_evictor(net, ip6_dst_idev(skb_dst(skb))); |
1da177e4 | 565 | |
9546377c SW |
566 | fq = fq_find(net, fhdr->identification, &hdr->saddr, &hdr->daddr); |
567 | if (fq != NULL) { | |
f61944ef | 568 | int ret; |
1da177e4 | 569 | |
5ab11c98 | 570 | spin_lock(&fq->q.lock); |
1da177e4 | 571 | |
f61944ef | 572 | ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff); |
1da177e4 | 573 | |
5ab11c98 | 574 | spin_unlock(&fq->q.lock); |
4b6cb5d8 | 575 | fq_put(fq); |
1da177e4 LT |
576 | return ret; |
577 | } | |
578 | ||
adf30907 | 579 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMFAILS); |
1da177e4 LT |
580 | kfree_skb(skb); |
581 | return -1; | |
98b3377c DL |
582 | |
583 | fail_hdr: | |
adf30907 | 584 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); |
98b3377c DL |
585 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb_network_header_len(skb)); |
586 | return -1; | |
1da177e4 LT |
587 | } |
588 | ||
41135cc8 | 589 | static const struct inet6_protocol frag_protocol = |
1da177e4 LT |
590 | { |
591 | .handler = ipv6_frag_rcv, | |
592 | .flags = INET6_PROTO_NOPOLICY, | |
593 | }; | |
594 | ||
8d8354d2 | 595 | #ifdef CONFIG_SYSCTL |
0a64b4b8 | 596 | static struct ctl_table ip6_frags_ns_ctl_table[] = { |
8d8354d2 | 597 | { |
8d8354d2 | 598 | .procname = "ip6frag_high_thresh", |
e31e0bdc | 599 | .data = &init_net.ipv6.frags.high_thresh, |
8d8354d2 PE |
600 | .maxlen = sizeof(int), |
601 | .mode = 0644, | |
6d9f239a | 602 | .proc_handler = proc_dointvec |
8d8354d2 PE |
603 | }, |
604 | { | |
8d8354d2 | 605 | .procname = "ip6frag_low_thresh", |
e31e0bdc | 606 | .data = &init_net.ipv6.frags.low_thresh, |
8d8354d2 PE |
607 | .maxlen = sizeof(int), |
608 | .mode = 0644, | |
6d9f239a | 609 | .proc_handler = proc_dointvec |
8d8354d2 PE |
610 | }, |
611 | { | |
8d8354d2 | 612 | .procname = "ip6frag_time", |
b2fd5321 | 613 | .data = &init_net.ipv6.frags.timeout, |
8d8354d2 PE |
614 | .maxlen = sizeof(int), |
615 | .mode = 0644, | |
6d9f239a | 616 | .proc_handler = proc_dointvec_jiffies, |
8d8354d2 | 617 | }, |
7d291ebb PE |
618 | { } |
619 | }; | |
620 | ||
621 | static struct ctl_table ip6_frags_ctl_table[] = { | |
8d8354d2 | 622 | { |
8d8354d2 | 623 | .procname = "ip6frag_secret_interval", |
3b4bc4a2 | 624 | .data = &ip6_frags.secret_interval, |
8d8354d2 PE |
625 | .maxlen = sizeof(int), |
626 | .mode = 0644, | |
6d9f239a | 627 | .proc_handler = proc_dointvec_jiffies, |
8d8354d2 PE |
628 | }, |
629 | { } | |
630 | }; | |
631 | ||
2c8c1e72 | 632 | static int __net_init ip6_frags_ns_sysctl_register(struct net *net) |
8d8354d2 | 633 | { |
e4a2d5c2 | 634 | struct ctl_table *table; |
8d8354d2 PE |
635 | struct ctl_table_header *hdr; |
636 | ||
0a64b4b8 | 637 | table = ip6_frags_ns_ctl_table; |
09ad9bc7 | 638 | if (!net_eq(net, &init_net)) { |
0a64b4b8 | 639 | table = kmemdup(table, sizeof(ip6_frags_ns_ctl_table), GFP_KERNEL); |
e4a2d5c2 PE |
640 | if (table == NULL) |
641 | goto err_alloc; | |
642 | ||
e31e0bdc PE |
643 | table[0].data = &net->ipv6.frags.high_thresh; |
644 | table[1].data = &net->ipv6.frags.low_thresh; | |
b2fd5321 | 645 | table[2].data = &net->ipv6.frags.timeout; |
e4a2d5c2 PE |
646 | } |
647 | ||
ec8f23ce | 648 | hdr = register_net_sysctl(net, "net/ipv6", table); |
e4a2d5c2 PE |
649 | if (hdr == NULL) |
650 | goto err_reg; | |
651 | ||
652 | net->ipv6.sysctl.frags_hdr = hdr; | |
653 | return 0; | |
654 | ||
655 | err_reg: | |
09ad9bc7 | 656 | if (!net_eq(net, &init_net)) |
e4a2d5c2 PE |
657 | kfree(table); |
658 | err_alloc: | |
659 | return -ENOMEM; | |
660 | } | |
661 | ||
2c8c1e72 | 662 | static void __net_exit ip6_frags_ns_sysctl_unregister(struct net *net) |
e4a2d5c2 PE |
663 | { |
664 | struct ctl_table *table; | |
665 | ||
666 | table = net->ipv6.sysctl.frags_hdr->ctl_table_arg; | |
667 | unregister_net_sysctl_table(net->ipv6.sysctl.frags_hdr); | |
3705e11a YH |
668 | if (!net_eq(net, &init_net)) |
669 | kfree(table); | |
8d8354d2 | 670 | } |
7d291ebb PE |
671 | |
672 | static struct ctl_table_header *ip6_ctl_header; | |
673 | ||
674 | static int ip6_frags_sysctl_register(void) | |
675 | { | |
43444757 | 676 | ip6_ctl_header = register_net_sysctl(&init_net, "net/ipv6", |
7d291ebb PE |
677 | ip6_frags_ctl_table); |
678 | return ip6_ctl_header == NULL ? -ENOMEM : 0; | |
679 | } | |
680 | ||
681 | static void ip6_frags_sysctl_unregister(void) | |
682 | { | |
683 | unregister_net_sysctl_table(ip6_ctl_header); | |
684 | } | |
8d8354d2 | 685 | #else |
0a64b4b8 | 686 | static inline int ip6_frags_ns_sysctl_register(struct net *net) |
e71e0349 | 687 | { |
8d8354d2 PE |
688 | return 0; |
689 | } | |
e4a2d5c2 | 690 | |
0a64b4b8 | 691 | static inline void ip6_frags_ns_sysctl_unregister(struct net *net) |
e4a2d5c2 PE |
692 | { |
693 | } | |
7d291ebb PE |
694 | |
695 | static inline int ip6_frags_sysctl_register(void) | |
696 | { | |
697 | return 0; | |
698 | } | |
699 | ||
700 | static inline void ip6_frags_sysctl_unregister(void) | |
701 | { | |
702 | } | |
8d8354d2 | 703 | #endif |
7d460db9 | 704 | |
2c8c1e72 | 705 | static int __net_init ipv6_frags_init_net(struct net *net) |
8d8354d2 | 706 | { |
7c070aa9 SW |
707 | net->ipv6.frags.high_thresh = IPV6_FRAG_HIGH_THRESH; |
708 | net->ipv6.frags.low_thresh = IPV6_FRAG_LOW_THRESH; | |
b2fd5321 | 709 | net->ipv6.frags.timeout = IPV6_FRAG_TIMEOUT; |
8d8354d2 | 710 | |
e5a2bb84 PE |
711 | inet_frags_init_net(&net->ipv6.frags); |
712 | ||
0a64b4b8 | 713 | return ip6_frags_ns_sysctl_register(net); |
e71e0349 DL |
714 | } |
715 | ||
2c8c1e72 | 716 | static void __net_exit ipv6_frags_exit_net(struct net *net) |
81566e83 | 717 | { |
0a64b4b8 | 718 | ip6_frags_ns_sysctl_unregister(net); |
81566e83 PE |
719 | inet_frags_exit_net(&net->ipv6.frags, &ip6_frags); |
720 | } | |
721 | ||
722 | static struct pernet_operations ip6_frags_ops = { | |
723 | .init = ipv6_frags_init_net, | |
724 | .exit = ipv6_frags_exit_net, | |
725 | }; | |
726 | ||
853cbbaa | 727 | int __init ipv6_frag_init(void) |
1da177e4 | 728 | { |
853cbbaa | 729 | int ret; |
1da177e4 | 730 | |
853cbbaa DL |
731 | ret = inet6_add_protocol(&frag_protocol, IPPROTO_FRAGMENT); |
732 | if (ret) | |
733 | goto out; | |
e71e0349 | 734 | |
7d291ebb PE |
735 | ret = ip6_frags_sysctl_register(); |
736 | if (ret) | |
737 | goto err_sysctl; | |
738 | ||
0002c630 PE |
739 | ret = register_pernet_subsys(&ip6_frags_ops); |
740 | if (ret) | |
741 | goto err_pernet; | |
8d8354d2 | 742 | |
321a3a99 | 743 | ip6_frags.hashfn = ip6_hashfn; |
c6fda282 | 744 | ip6_frags.constructor = ip6_frag_init; |
c9547709 | 745 | ip6_frags.destructor = NULL; |
1e4b8287 PE |
746 | ip6_frags.skb_free = NULL; |
747 | ip6_frags.qsize = sizeof(struct frag_queue); | |
abd6523d | 748 | ip6_frags.match = ip6_frag_match; |
e521db9d | 749 | ip6_frags.frag_expire = ip6_frag_expire; |
3b4bc4a2 | 750 | ip6_frags.secret_interval = 10 * 60 * HZ; |
7eb95156 | 751 | inet_frags_init(&ip6_frags); |
853cbbaa DL |
752 | out: |
753 | return ret; | |
0002c630 PE |
754 | |
755 | err_pernet: | |
7d291ebb PE |
756 | ip6_frags_sysctl_unregister(); |
757 | err_sysctl: | |
0002c630 PE |
758 | inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT); |
759 | goto out; | |
853cbbaa DL |
760 | } |
761 | ||
762 | void ipv6_frag_exit(void) | |
763 | { | |
764 | inet_frags_fini(&ip6_frags); | |
7d291ebb | 765 | ip6_frags_sysctl_unregister(); |
81566e83 | 766 | unregister_pernet_subsys(&ip6_frags_ops); |
853cbbaa | 767 | inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT); |
1da177e4 | 768 | } |