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 | ||
7eb95156 | 68 | static struct inet_frags ip6_frags; |
1da177e4 | 69 | |
f61944ef HX |
70 | static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev, |
71 | struct net_device *dev); | |
72 | ||
f6596f9d ZB |
73 | /* |
74 | * callers should be careful not to use the hash value outside the ipfrag_lock | |
75 | * as doing so could race with ipfrag_hash_rnd being recalculated. | |
76 | */ | |
93c8b90f IJ |
77 | unsigned int inet6_hash_frag(__be32 id, const struct in6_addr *saddr, |
78 | const struct in6_addr *daddr, u32 rnd) | |
1da177e4 | 79 | { |
82a39eb6 JK |
80 | u32 c; |
81 | ||
82 | c = jhash_3words((__force u32)saddr->s6_addr32[0], | |
83 | (__force u32)saddr->s6_addr32[1], | |
84 | (__force u32)saddr->s6_addr32[2], | |
85 | rnd); | |
86 | ||
87 | c = jhash_3words((__force u32)saddr->s6_addr32[3], | |
88 | (__force u32)daddr->s6_addr32[0], | |
89 | (__force u32)daddr->s6_addr32[1], | |
90 | c); | |
91 | ||
92 | c = jhash_3words((__force u32)daddr->s6_addr32[2], | |
93 | (__force u32)daddr->s6_addr32[3], | |
94 | (__force u32)id, | |
95 | c); | |
1da177e4 | 96 | |
7eb95156 | 97 | return c & (INETFRAGS_HASHSZ - 1); |
1da177e4 | 98 | } |
93c8b90f | 99 | EXPORT_SYMBOL_GPL(inet6_hash_frag); |
1da177e4 | 100 | |
321a3a99 | 101 | static unsigned int ip6_hashfn(struct inet_frag_queue *q) |
1da177e4 | 102 | { |
321a3a99 | 103 | struct frag_queue *fq; |
1da177e4 | 104 | |
321a3a99 | 105 | fq = container_of(q, struct frag_queue, q); |
93c8b90f | 106 | return inet6_hash_frag(fq->id, &fq->saddr, &fq->daddr, ip6_frags.rnd); |
1da177e4 LT |
107 | } |
108 | ||
cbc264ca | 109 | bool ip6_frag_match(struct inet_frag_queue *q, void *a) |
abd6523d PE |
110 | { |
111 | struct frag_queue *fq; | |
112 | struct ip6_create_arg *arg = a; | |
113 | ||
114 | fq = container_of(q, struct frag_queue, q); | |
cbc264ca ED |
115 | return fq->id == arg->id && |
116 | fq->user == arg->user && | |
117 | ipv6_addr_equal(&fq->saddr, arg->src) && | |
118 | ipv6_addr_equal(&fq->daddr, arg->dst); | |
abd6523d PE |
119 | } |
120 | EXPORT_SYMBOL(ip6_frag_match); | |
121 | ||
c6fda282 | 122 | void ip6_frag_init(struct inet_frag_queue *q, void *a) |
1da177e4 | 123 | { |
c6fda282 PE |
124 | struct frag_queue *fq = container_of(q, struct frag_queue, q); |
125 | struct ip6_create_arg *arg = a; | |
126 | ||
127 | fq->id = arg->id; | |
0b5ccb2e | 128 | fq->user = arg->user; |
4e3fd7a0 AD |
129 | fq->saddr = *arg->src; |
130 | fq->daddr = *arg->dst; | |
1da177e4 | 131 | } |
c6fda282 | 132 | EXPORT_SYMBOL(ip6_frag_init); |
1da177e4 | 133 | |
b836c99f AW |
134 | void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq, |
135 | struct inet_frags *frags) | |
1da177e4 | 136 | { |
a11d206d | 137 | struct net_device *dev = NULL; |
e521db9d | 138 | |
5ab11c98 | 139 | spin_lock(&fq->q.lock); |
1da177e4 | 140 | |
bc578a54 | 141 | if (fq->q.last_in & INET_FRAG_COMPLETE) |
1da177e4 LT |
142 | goto out; |
143 | ||
b836c99f | 144 | inet_frag_kill(&fq->q, frags); |
1da177e4 | 145 | |
69df9d59 ED |
146 | rcu_read_lock(); |
147 | dev = dev_get_by_index_rcu(net, fq->iif); | |
a11d206d | 148 | if (!dev) |
69df9d59 | 149 | goto out_rcu_unlock; |
a11d206d | 150 | |
483a47d2 DL |
151 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT); |
152 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS); | |
1da177e4 | 153 | |
78c784c4 | 154 | /* Don't send error if the first segment did not arrive. */ |
bc578a54 | 155 | if (!(fq->q.last_in & INET_FRAG_FIRST_IN) || !fq->q.fragments) |
69df9d59 | 156 | goto out_rcu_unlock; |
78c784c4 | 157 | |
78c784c4 IO |
158 | /* |
159 | But use as source device on which LAST ARRIVED | |
160 | segment was received. And do not use fq->dev | |
161 | pointer directly, device might already disappeared. | |
162 | */ | |
5ab11c98 | 163 | fq->q.fragments->dev = dev; |
3ffe533c | 164 | icmpv6_send(fq->q.fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0); |
69df9d59 ED |
165 | out_rcu_unlock: |
166 | rcu_read_unlock(); | |
1da177e4 | 167 | out: |
5ab11c98 | 168 | spin_unlock(&fq->q.lock); |
b836c99f AW |
169 | inet_frag_put(&fq->q, frags); |
170 | } | |
171 | EXPORT_SYMBOL(ip6_expire_frag_queue); | |
172 | ||
173 | static void ip6_frag_expire(unsigned long data) | |
174 | { | |
175 | struct frag_queue *fq; | |
176 | struct net *net; | |
177 | ||
178 | fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q); | |
179 | net = container_of(fq->q.net, struct net, ipv6.frags); | |
180 | ||
181 | ip6_expire_frag_queue(net, fq, &ip6_frags); | |
1da177e4 LT |
182 | } |
183 | ||
abd6523d | 184 | static __inline__ struct frag_queue * |
b71d1d42 | 185 | fq_find(struct net *net, __be32 id, const struct in6_addr *src, const struct in6_addr *dst) |
1da177e4 | 186 | { |
c6fda282 PE |
187 | struct inet_frag_queue *q; |
188 | struct ip6_create_arg arg; | |
abd6523d | 189 | unsigned int hash; |
1da177e4 | 190 | |
c6fda282 | 191 | arg.id = id; |
0b5ccb2e | 192 | arg.user = IP6_DEFRAG_LOCAL_DELIVER; |
c6fda282 PE |
193 | arg.src = src; |
194 | arg.dst = dst; | |
9a375803 PE |
195 | |
196 | read_lock(&ip6_frags.lock); | |
93c8b90f | 197 | hash = inet6_hash_frag(id, src, dst, ip6_frags.rnd); |
1da177e4 | 198 | |
ac18e750 | 199 | q = inet_frag_find(&net->ipv6.frags, &ip6_frags, &arg, hash); |
c6fda282 | 200 | if (q == NULL) |
9546377c | 201 | return NULL; |
1da177e4 | 202 | |
c6fda282 | 203 | return container_of(q, struct frag_queue, q); |
1da177e4 LT |
204 | } |
205 | ||
f61944ef | 206 | static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, |
1da177e4 LT |
207 | struct frag_hdr *fhdr, int nhoff) |
208 | { | |
209 | struct sk_buff *prev, *next; | |
f61944ef | 210 | struct net_device *dev; |
1da177e4 | 211 | int offset, end; |
adf30907 | 212 | struct net *net = dev_net(skb_dst(skb)->dev); |
1da177e4 | 213 | |
bc578a54 | 214 | if (fq->q.last_in & INET_FRAG_COMPLETE) |
1da177e4 LT |
215 | goto err; |
216 | ||
217 | offset = ntohs(fhdr->frag_off) & ~0x7; | |
0660e03f ACM |
218 | end = offset + (ntohs(ipv6_hdr(skb)->payload_len) - |
219 | ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1))); | |
1da177e4 LT |
220 | |
221 | if ((unsigned int)end > IPV6_MAXPLEN) { | |
adf30907 | 222 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 223 | IPSTATS_MIB_INHDRERRORS); |
d56f90a7 ACM |
224 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
225 | ((u8 *)&fhdr->frag_off - | |
226 | skb_network_header(skb))); | |
f61944ef | 227 | return -1; |
1da177e4 LT |
228 | } |
229 | ||
d56f90a7 ACM |
230 | if (skb->ip_summed == CHECKSUM_COMPLETE) { |
231 | const unsigned char *nh = skb_network_header(skb); | |
1ab1457c | 232 | skb->csum = csum_sub(skb->csum, |
d56f90a7 ACM |
233 | csum_partial(nh, (u8 *)(fhdr + 1) - nh, |
234 | 0)); | |
235 | } | |
1da177e4 LT |
236 | |
237 | /* Is this the final fragment? */ | |
238 | if (!(fhdr->frag_off & htons(IP6_MF))) { | |
239 | /* If we already have some bits beyond end | |
240 | * or have different end, the segment is corrupted. | |
241 | */ | |
5ab11c98 | 242 | if (end < fq->q.len || |
bc578a54 | 243 | ((fq->q.last_in & INET_FRAG_LAST_IN) && end != fq->q.len)) |
1da177e4 | 244 | goto err; |
bc578a54 | 245 | fq->q.last_in |= INET_FRAG_LAST_IN; |
5ab11c98 | 246 | fq->q.len = end; |
1da177e4 LT |
247 | } else { |
248 | /* Check if the fragment is rounded to 8 bytes. | |
249 | * Required by the RFC. | |
250 | */ | |
251 | if (end & 0x7) { | |
252 | /* RFC2460 says always send parameter problem in | |
253 | * this case. -DaveM | |
254 | */ | |
adf30907 | 255 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 256 | IPSTATS_MIB_INHDRERRORS); |
1ab1457c | 257 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
1da177e4 | 258 | offsetof(struct ipv6hdr, payload_len)); |
f61944ef | 259 | return -1; |
1da177e4 | 260 | } |
5ab11c98 | 261 | if (end > fq->q.len) { |
1da177e4 | 262 | /* Some bits beyond end -> corruption. */ |
bc578a54 | 263 | if (fq->q.last_in & INET_FRAG_LAST_IN) |
1da177e4 | 264 | goto err; |
5ab11c98 | 265 | fq->q.len = end; |
1da177e4 LT |
266 | } |
267 | } | |
268 | ||
269 | if (end == offset) | |
270 | goto err; | |
271 | ||
272 | /* Point into the IP datagram 'data' part. */ | |
273 | if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) | |
274 | goto err; | |
1ab1457c | 275 | |
42ca89c1 SH |
276 | if (pskb_trim_rcsum(skb, end - offset)) |
277 | goto err; | |
1da177e4 LT |
278 | |
279 | /* Find out which fragments are in front and at the back of us | |
280 | * in the chain of fragments so far. We must know where to put | |
281 | * this fragment, right? | |
282 | */ | |
d6bebca9 CG |
283 | prev = fq->q.fragments_tail; |
284 | if (!prev || FRAG6_CB(prev)->offset < offset) { | |
285 | next = NULL; | |
286 | goto found; | |
287 | } | |
1da177e4 | 288 | prev = NULL; |
5ab11c98 | 289 | for(next = fq->q.fragments; next != NULL; next = next->next) { |
1da177e4 LT |
290 | if (FRAG6_CB(next)->offset >= offset) |
291 | break; /* bingo! */ | |
292 | prev = next; | |
293 | } | |
294 | ||
d6bebca9 | 295 | found: |
5de658f8 ED |
296 | /* RFC5722, Section 4, amended by Errata ID : 3089 |
297 | * When reassembling an IPv6 datagram, if | |
70789d70 ND |
298 | * one or more its constituent fragments is determined to be an |
299 | * overlapping fragment, the entire datagram (and any constituent | |
5de658f8 | 300 | * fragments) MUST be silently discarded. |
1da177e4 | 301 | */ |
1da177e4 | 302 | |
70789d70 ND |
303 | /* Check for overlap with preceding fragment. */ |
304 | if (prev && | |
f4642141 | 305 | (FRAG6_CB(prev)->offset + prev->len) > offset) |
70789d70 | 306 | goto discard_fq; |
1da177e4 | 307 | |
70789d70 ND |
308 | /* Look for overlap with succeeding segment. */ |
309 | if (next && FRAG6_CB(next)->offset < end) | |
310 | goto discard_fq; | |
1da177e4 LT |
311 | |
312 | FRAG6_CB(skb)->offset = offset; | |
313 | ||
314 | /* Insert this fragment in the chain of fragments. */ | |
315 | skb->next = next; | |
d6bebca9 CG |
316 | if (!next) |
317 | fq->q.fragments_tail = skb; | |
1da177e4 LT |
318 | if (prev) |
319 | prev->next = skb; | |
320 | else | |
5ab11c98 | 321 | fq->q.fragments = skb; |
1da177e4 | 322 | |
f61944ef HX |
323 | dev = skb->dev; |
324 | if (dev) { | |
325 | fq->iif = dev->ifindex; | |
326 | skb->dev = NULL; | |
327 | } | |
5ab11c98 PE |
328 | fq->q.stamp = skb->tstamp; |
329 | fq->q.meat += skb->len; | |
6ddc0822 | 330 | atomic_add(skb->truesize, &fq->q.net->mem); |
1da177e4 LT |
331 | |
332 | /* The first fragment. | |
333 | * nhoffset is obtained from the first fragment, of course. | |
334 | */ | |
335 | if (offset == 0) { | |
336 | fq->nhoffset = nhoff; | |
bc578a54 | 337 | fq->q.last_in |= INET_FRAG_FIRST_IN; |
1da177e4 | 338 | } |
f61944ef | 339 | |
bc578a54 JP |
340 | if (fq->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && |
341 | fq->q.meat == fq->q.len) | |
f61944ef HX |
342 | return ip6_frag_reasm(fq, prev, dev); |
343 | ||
7eb95156 | 344 | write_lock(&ip6_frags.lock); |
3140c25c | 345 | list_move_tail(&fq->q.lru_list, &fq->q.net->lru_list); |
7eb95156 | 346 | write_unlock(&ip6_frags.lock); |
f61944ef | 347 | return -1; |
1da177e4 | 348 | |
70789d70 | 349 | discard_fq: |
b836c99f | 350 | inet_frag_kill(&fq->q, &ip6_frags); |
1da177e4 | 351 | err: |
adf30907 | 352 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
3bd653c8 | 353 | IPSTATS_MIB_REASMFAILS); |
1da177e4 | 354 | kfree_skb(skb); |
f61944ef | 355 | return -1; |
1da177e4 LT |
356 | } |
357 | ||
358 | /* | |
359 | * Check if this packet is complete. | |
360 | * Returns NULL on failure by any reason, and pointer | |
361 | * to current nexthdr field in reassembled frame. | |
362 | * | |
363 | * It is called with locked fq, and caller must check that | |
364 | * queue is eligible for reassembly i.e. it is not COMPLETE, | |
365 | * the last and the first frames arrived and all the bits are here. | |
366 | */ | |
f61944ef | 367 | static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev, |
1da177e4 LT |
368 | struct net_device *dev) |
369 | { | |
2bad35b7 | 370 | struct net *net = container_of(fq->q.net, struct net, ipv6.frags); |
5ab11c98 | 371 | struct sk_buff *fp, *head = fq->q.fragments; |
1da177e4 LT |
372 | int payload_len; |
373 | unsigned int nhoff; | |
ec16439e | 374 | int sum_truesize; |
1da177e4 | 375 | |
b836c99f | 376 | inet_frag_kill(&fq->q, &ip6_frags); |
1da177e4 | 377 | |
f61944ef HX |
378 | /* Make the one we just received the head. */ |
379 | if (prev) { | |
380 | head = prev->next; | |
381 | fp = skb_clone(head, GFP_ATOMIC); | |
382 | ||
383 | if (!fp) | |
384 | goto out_oom; | |
385 | ||
386 | fp->next = head->next; | |
d6bebca9 CG |
387 | if (!fp->next) |
388 | fq->q.fragments_tail = fp; | |
f61944ef HX |
389 | prev->next = fp; |
390 | ||
5ab11c98 PE |
391 | skb_morph(head, fq->q.fragments); |
392 | head->next = fq->q.fragments->next; | |
f61944ef | 393 | |
808db80a | 394 | consume_skb(fq->q.fragments); |
5ab11c98 | 395 | fq->q.fragments = head; |
f61944ef HX |
396 | } |
397 | ||
547b792c IJ |
398 | WARN_ON(head == NULL); |
399 | WARN_ON(FRAG6_CB(head)->offset != 0); | |
1da177e4 LT |
400 | |
401 | /* Unfragmented part is taken from the first segment. */ | |
d56f90a7 | 402 | payload_len = ((head->data - skb_network_header(head)) - |
5ab11c98 | 403 | sizeof(struct ipv6hdr) + fq->q.len - |
d56f90a7 | 404 | sizeof(struct frag_hdr)); |
1da177e4 LT |
405 | if (payload_len > IPV6_MAXPLEN) |
406 | goto out_oversize; | |
407 | ||
408 | /* Head of list must not be cloned. */ | |
409 | if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) | |
410 | goto out_oom; | |
411 | ||
412 | /* If the first fragment is fragmented itself, we split | |
413 | * it to two chunks: the first with data and paged part | |
414 | * and the second, holding only fragments. */ | |
21dc3301 | 415 | if (skb_has_frag_list(head)) { |
1da177e4 LT |
416 | struct sk_buff *clone; |
417 | int i, plen = 0; | |
418 | ||
419 | if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) | |
420 | goto out_oom; | |
421 | clone->next = head->next; | |
422 | head->next = clone; | |
423 | skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; | |
4d9092bb | 424 | skb_frag_list_init(head); |
9e903e08 ED |
425 | for (i = 0; i < skb_shinfo(head)->nr_frags; i++) |
426 | plen += skb_frag_size(&skb_shinfo(head)->frags[i]); | |
1da177e4 LT |
427 | clone->len = clone->data_len = head->data_len - plen; |
428 | head->data_len -= clone->len; | |
429 | head->len -= clone->len; | |
430 | clone->csum = 0; | |
431 | clone->ip_summed = head->ip_summed; | |
6ddc0822 | 432 | atomic_add(clone->truesize, &fq->q.net->mem); |
1da177e4 LT |
433 | } |
434 | ||
435 | /* We have to remove fragment header from datagram and to relocate | |
436 | * header in order to calculate ICV correctly. */ | |
437 | nhoff = fq->nhoffset; | |
b0e380b1 | 438 | skb_network_header(head)[nhoff] = skb_transport_header(head)[0]; |
1ab1457c | 439 | memmove(head->head + sizeof(struct frag_hdr), head->head, |
1da177e4 | 440 | (head->data - head->head) - sizeof(struct frag_hdr)); |
b0e380b1 ACM |
441 | head->mac_header += sizeof(struct frag_hdr); |
442 | head->network_header += sizeof(struct frag_hdr); | |
1da177e4 | 443 | |
badff6d0 | 444 | skb_reset_transport_header(head); |
d56f90a7 | 445 | skb_push(head, head->data - skb_network_header(head)); |
1da177e4 | 446 | |
ec16439e ED |
447 | sum_truesize = head->truesize; |
448 | for (fp = head->next; fp;) { | |
449 | bool headstolen; | |
450 | int delta; | |
451 | struct sk_buff *next = fp->next; | |
452 | ||
453 | sum_truesize += fp->truesize; | |
1da177e4 LT |
454 | if (head->ip_summed != fp->ip_summed) |
455 | head->ip_summed = CHECKSUM_NONE; | |
84fa7933 | 456 | else if (head->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 | 457 | head->csum = csum_add(head->csum, fp->csum); |
ec16439e ED |
458 | |
459 | if (skb_try_coalesce(head, fp, &headstolen, &delta)) { | |
460 | kfree_skb_partial(fp, headstolen); | |
461 | } else { | |
462 | if (!skb_shinfo(head)->frag_list) | |
463 | skb_shinfo(head)->frag_list = fp; | |
464 | head->data_len += fp->len; | |
465 | head->len += fp->len; | |
466 | head->truesize += fp->truesize; | |
467 | } | |
468 | fp = next; | |
1da177e4 | 469 | } |
ec16439e | 470 | atomic_sub(sum_truesize, &fq->q.net->mem); |
1da177e4 LT |
471 | |
472 | head->next = NULL; | |
473 | head->dev = dev; | |
5ab11c98 | 474 | head->tstamp = fq->q.stamp; |
0660e03f | 475 | ipv6_hdr(head)->payload_len = htons(payload_len); |
951dbc8a | 476 | IP6CB(head)->nhoff = nhoff; |
1da177e4 | 477 | |
1da177e4 | 478 | /* Yes, and fold redundant checksum back. 8) */ |
84fa7933 | 479 | if (head->ip_summed == CHECKSUM_COMPLETE) |
d56f90a7 | 480 | head->csum = csum_partial(skb_network_header(head), |
cfe1fc77 | 481 | skb_network_header_len(head), |
d56f90a7 | 482 | head->csum); |
1da177e4 | 483 | |
a11d206d | 484 | rcu_read_lock(); |
2bad35b7 | 485 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMOKS); |
a11d206d | 486 | rcu_read_unlock(); |
5ab11c98 | 487 | fq->q.fragments = NULL; |
d6bebca9 | 488 | fq->q.fragments_tail = NULL; |
1da177e4 LT |
489 | return 1; |
490 | ||
491 | out_oversize: | |
e87cc472 | 492 | net_dbg_ratelimited("ip6_frag_reasm: payload len = %d\n", payload_len); |
1da177e4 LT |
493 | goto out_fail; |
494 | out_oom: | |
e87cc472 | 495 | net_dbg_ratelimited("ip6_frag_reasm: no memory for reassembly\n"); |
1da177e4 | 496 | out_fail: |
a11d206d | 497 | rcu_read_lock(); |
2bad35b7 | 498 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS); |
a11d206d | 499 | rcu_read_unlock(); |
1da177e4 LT |
500 | return -1; |
501 | } | |
502 | ||
e5bbef20 | 503 | static int ipv6_frag_rcv(struct sk_buff *skb) |
1da177e4 | 504 | { |
1da177e4 LT |
505 | struct frag_hdr *fhdr; |
506 | struct frag_queue *fq; | |
b71d1d42 | 507 | const struct ipv6hdr *hdr = ipv6_hdr(skb); |
adf30907 | 508 | struct net *net = dev_net(skb_dst(skb)->dev); |
6b102865 | 509 | int evicted; |
1da177e4 | 510 | |
adf30907 | 511 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMREQDS); |
1da177e4 LT |
512 | |
513 | /* Jumbo payload inhibits frag. header */ | |
98b3377c DL |
514 | if (hdr->payload_len==0) |
515 | goto fail_hdr; | |
516 | ||
ea2ae17d | 517 | if (!pskb_may_pull(skb, (skb_transport_offset(skb) + |
98b3377c DL |
518 | sizeof(struct frag_hdr)))) |
519 | goto fail_hdr; | |
1da177e4 | 520 | |
0660e03f | 521 | hdr = ipv6_hdr(skb); |
9c70220b | 522 | fhdr = (struct frag_hdr *)skb_transport_header(skb); |
1da177e4 LT |
523 | |
524 | if (!(fhdr->frag_off & htons(0xFFF9))) { | |
525 | /* It is not a fragmented frame */ | |
b0e380b1 | 526 | skb->transport_header += sizeof(struct frag_hdr); |
483a47d2 | 527 | IP6_INC_STATS_BH(net, |
adf30907 | 528 | ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMOKS); |
1da177e4 | 529 | |
d56f90a7 | 530 | IP6CB(skb)->nhoff = (u8 *)fhdr - skb_network_header(skb); |
1da177e4 LT |
531 | return 1; |
532 | } | |
533 | ||
6b102865 AW |
534 | evicted = inet_frag_evictor(&net->ipv6.frags, &ip6_frags, false); |
535 | if (evicted) | |
536 | IP6_ADD_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), | |
537 | IPSTATS_MIB_REASMFAILS, evicted); | |
1da177e4 | 538 | |
9546377c SW |
539 | fq = fq_find(net, fhdr->identification, &hdr->saddr, &hdr->daddr); |
540 | if (fq != NULL) { | |
f61944ef | 541 | int ret; |
1da177e4 | 542 | |
5ab11c98 | 543 | spin_lock(&fq->q.lock); |
1da177e4 | 544 | |
f61944ef | 545 | ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff); |
1da177e4 | 546 | |
5ab11c98 | 547 | spin_unlock(&fq->q.lock); |
b836c99f | 548 | inet_frag_put(&fq->q, &ip6_frags); |
1da177e4 LT |
549 | return ret; |
550 | } | |
551 | ||
adf30907 | 552 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMFAILS); |
1da177e4 LT |
553 | kfree_skb(skb); |
554 | return -1; | |
98b3377c DL |
555 | |
556 | fail_hdr: | |
adf30907 | 557 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); |
98b3377c DL |
558 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb_network_header_len(skb)); |
559 | return -1; | |
1da177e4 LT |
560 | } |
561 | ||
41135cc8 | 562 | static const struct inet6_protocol frag_protocol = |
1da177e4 LT |
563 | { |
564 | .handler = ipv6_frag_rcv, | |
565 | .flags = INET6_PROTO_NOPOLICY, | |
566 | }; | |
567 | ||
8d8354d2 | 568 | #ifdef CONFIG_SYSCTL |
0a64b4b8 | 569 | static struct ctl_table ip6_frags_ns_ctl_table[] = { |
8d8354d2 | 570 | { |
8d8354d2 | 571 | .procname = "ip6frag_high_thresh", |
e31e0bdc | 572 | .data = &init_net.ipv6.frags.high_thresh, |
8d8354d2 PE |
573 | .maxlen = sizeof(int), |
574 | .mode = 0644, | |
6d9f239a | 575 | .proc_handler = proc_dointvec |
8d8354d2 PE |
576 | }, |
577 | { | |
8d8354d2 | 578 | .procname = "ip6frag_low_thresh", |
e31e0bdc | 579 | .data = &init_net.ipv6.frags.low_thresh, |
8d8354d2 PE |
580 | .maxlen = sizeof(int), |
581 | .mode = 0644, | |
6d9f239a | 582 | .proc_handler = proc_dointvec |
8d8354d2 PE |
583 | }, |
584 | { | |
8d8354d2 | 585 | .procname = "ip6frag_time", |
b2fd5321 | 586 | .data = &init_net.ipv6.frags.timeout, |
8d8354d2 PE |
587 | .maxlen = sizeof(int), |
588 | .mode = 0644, | |
6d9f239a | 589 | .proc_handler = proc_dointvec_jiffies, |
8d8354d2 | 590 | }, |
7d291ebb PE |
591 | { } |
592 | }; | |
593 | ||
594 | static struct ctl_table ip6_frags_ctl_table[] = { | |
8d8354d2 | 595 | { |
8d8354d2 | 596 | .procname = "ip6frag_secret_interval", |
3b4bc4a2 | 597 | .data = &ip6_frags.secret_interval, |
8d8354d2 PE |
598 | .maxlen = sizeof(int), |
599 | .mode = 0644, | |
6d9f239a | 600 | .proc_handler = proc_dointvec_jiffies, |
8d8354d2 PE |
601 | }, |
602 | { } | |
603 | }; | |
604 | ||
2c8c1e72 | 605 | static int __net_init ip6_frags_ns_sysctl_register(struct net *net) |
8d8354d2 | 606 | { |
e4a2d5c2 | 607 | struct ctl_table *table; |
8d8354d2 PE |
608 | struct ctl_table_header *hdr; |
609 | ||
0a64b4b8 | 610 | table = ip6_frags_ns_ctl_table; |
09ad9bc7 | 611 | if (!net_eq(net, &init_net)) { |
0a64b4b8 | 612 | table = kmemdup(table, sizeof(ip6_frags_ns_ctl_table), GFP_KERNEL); |
e4a2d5c2 PE |
613 | if (table == NULL) |
614 | goto err_alloc; | |
615 | ||
e31e0bdc PE |
616 | table[0].data = &net->ipv6.frags.high_thresh; |
617 | table[1].data = &net->ipv6.frags.low_thresh; | |
b2fd5321 | 618 | table[2].data = &net->ipv6.frags.timeout; |
e4a2d5c2 PE |
619 | } |
620 | ||
ec8f23ce | 621 | hdr = register_net_sysctl(net, "net/ipv6", table); |
e4a2d5c2 PE |
622 | if (hdr == NULL) |
623 | goto err_reg; | |
624 | ||
625 | net->ipv6.sysctl.frags_hdr = hdr; | |
626 | return 0; | |
627 | ||
628 | err_reg: | |
09ad9bc7 | 629 | if (!net_eq(net, &init_net)) |
e4a2d5c2 PE |
630 | kfree(table); |
631 | err_alloc: | |
632 | return -ENOMEM; | |
633 | } | |
634 | ||
2c8c1e72 | 635 | static void __net_exit ip6_frags_ns_sysctl_unregister(struct net *net) |
e4a2d5c2 PE |
636 | { |
637 | struct ctl_table *table; | |
638 | ||
639 | table = net->ipv6.sysctl.frags_hdr->ctl_table_arg; | |
640 | unregister_net_sysctl_table(net->ipv6.sysctl.frags_hdr); | |
3705e11a YH |
641 | if (!net_eq(net, &init_net)) |
642 | kfree(table); | |
8d8354d2 | 643 | } |
7d291ebb PE |
644 | |
645 | static struct ctl_table_header *ip6_ctl_header; | |
646 | ||
647 | static int ip6_frags_sysctl_register(void) | |
648 | { | |
43444757 | 649 | ip6_ctl_header = register_net_sysctl(&init_net, "net/ipv6", |
7d291ebb PE |
650 | ip6_frags_ctl_table); |
651 | return ip6_ctl_header == NULL ? -ENOMEM : 0; | |
652 | } | |
653 | ||
654 | static void ip6_frags_sysctl_unregister(void) | |
655 | { | |
656 | unregister_net_sysctl_table(ip6_ctl_header); | |
657 | } | |
8d8354d2 | 658 | #else |
0a64b4b8 | 659 | static inline int ip6_frags_ns_sysctl_register(struct net *net) |
e71e0349 | 660 | { |
8d8354d2 PE |
661 | return 0; |
662 | } | |
e4a2d5c2 | 663 | |
0a64b4b8 | 664 | static inline void ip6_frags_ns_sysctl_unregister(struct net *net) |
e4a2d5c2 PE |
665 | { |
666 | } | |
7d291ebb PE |
667 | |
668 | static inline int ip6_frags_sysctl_register(void) | |
669 | { | |
670 | return 0; | |
671 | } | |
672 | ||
673 | static inline void ip6_frags_sysctl_unregister(void) | |
674 | { | |
675 | } | |
8d8354d2 | 676 | #endif |
7d460db9 | 677 | |
2c8c1e72 | 678 | static int __net_init ipv6_frags_init_net(struct net *net) |
8d8354d2 | 679 | { |
7c070aa9 SW |
680 | net->ipv6.frags.high_thresh = IPV6_FRAG_HIGH_THRESH; |
681 | net->ipv6.frags.low_thresh = IPV6_FRAG_LOW_THRESH; | |
b2fd5321 | 682 | net->ipv6.frags.timeout = IPV6_FRAG_TIMEOUT; |
8d8354d2 | 683 | |
e5a2bb84 PE |
684 | inet_frags_init_net(&net->ipv6.frags); |
685 | ||
0a64b4b8 | 686 | return ip6_frags_ns_sysctl_register(net); |
e71e0349 DL |
687 | } |
688 | ||
2c8c1e72 | 689 | static void __net_exit ipv6_frags_exit_net(struct net *net) |
81566e83 | 690 | { |
0a64b4b8 | 691 | ip6_frags_ns_sysctl_unregister(net); |
81566e83 PE |
692 | inet_frags_exit_net(&net->ipv6.frags, &ip6_frags); |
693 | } | |
694 | ||
695 | static struct pernet_operations ip6_frags_ops = { | |
696 | .init = ipv6_frags_init_net, | |
697 | .exit = ipv6_frags_exit_net, | |
698 | }; | |
699 | ||
853cbbaa | 700 | int __init ipv6_frag_init(void) |
1da177e4 | 701 | { |
853cbbaa | 702 | int ret; |
1da177e4 | 703 | |
853cbbaa DL |
704 | ret = inet6_add_protocol(&frag_protocol, IPPROTO_FRAGMENT); |
705 | if (ret) | |
706 | goto out; | |
e71e0349 | 707 | |
7d291ebb PE |
708 | ret = ip6_frags_sysctl_register(); |
709 | if (ret) | |
710 | goto err_sysctl; | |
711 | ||
0002c630 PE |
712 | ret = register_pernet_subsys(&ip6_frags_ops); |
713 | if (ret) | |
714 | goto err_pernet; | |
8d8354d2 | 715 | |
321a3a99 | 716 | ip6_frags.hashfn = ip6_hashfn; |
c6fda282 | 717 | ip6_frags.constructor = ip6_frag_init; |
c9547709 | 718 | ip6_frags.destructor = NULL; |
1e4b8287 PE |
719 | ip6_frags.skb_free = NULL; |
720 | ip6_frags.qsize = sizeof(struct frag_queue); | |
abd6523d | 721 | ip6_frags.match = ip6_frag_match; |
e521db9d | 722 | ip6_frags.frag_expire = ip6_frag_expire; |
3b4bc4a2 | 723 | ip6_frags.secret_interval = 10 * 60 * HZ; |
7eb95156 | 724 | inet_frags_init(&ip6_frags); |
853cbbaa DL |
725 | out: |
726 | return ret; | |
0002c630 PE |
727 | |
728 | err_pernet: | |
7d291ebb PE |
729 | ip6_frags_sysctl_unregister(); |
730 | err_sysctl: | |
0002c630 PE |
731 | inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT); |
732 | goto out; | |
853cbbaa DL |
733 | } |
734 | ||
735 | void ipv6_frag_exit(void) | |
736 | { | |
737 | inet_frags_fini(&ip6_frags); | |
7d291ebb | 738 | ip6_frags_sysctl_unregister(); |
81566e83 | 739 | unregister_pernet_subsys(&ip6_frags_ops); |
853cbbaa | 740 | inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT); |
1da177e4 | 741 | } |