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 | */ | |
5a3da1fe HFS |
29 | |
30 | #define pr_fmt(fmt) "IPv6: " fmt | |
31 | ||
1da177e4 LT |
32 | #include <linux/errno.h> |
33 | #include <linux/types.h> | |
34 | #include <linux/string.h> | |
35 | #include <linux/socket.h> | |
36 | #include <linux/sockios.h> | |
37 | #include <linux/jiffies.h> | |
38 | #include <linux/net.h> | |
39 | #include <linux/list.h> | |
40 | #include <linux/netdevice.h> | |
41 | #include <linux/in6.h> | |
42 | #include <linux/ipv6.h> | |
43 | #include <linux/icmpv6.h> | |
44 | #include <linux/random.h> | |
45 | #include <linux/jhash.h> | |
f61944ef | 46 | #include <linux/skbuff.h> |
5a0e3ad6 | 47 | #include <linux/slab.h> |
bc3b2d7f | 48 | #include <linux/export.h> |
1da177e4 LT |
49 | |
50 | #include <net/sock.h> | |
51 | #include <net/snmp.h> | |
52 | ||
53 | #include <net/ipv6.h> | |
a11d206d | 54 | #include <net/ip6_route.h> |
1da177e4 LT |
55 | #include <net/protocol.h> |
56 | #include <net/transp_v6.h> | |
57 | #include <net/rawv6.h> | |
58 | #include <net/ndisc.h> | |
59 | #include <net/addrconf.h> | |
5ab11c98 | 60 | #include <net/inet_frag.h> |
1da177e4 | 61 | |
1da177e4 LT |
62 | struct ip6frag_skb_cb |
63 | { | |
64 | struct inet6_skb_parm h; | |
65 | int offset; | |
66 | }; | |
67 | ||
68 | #define FRAG6_CB(skb) ((struct ip6frag_skb_cb*)((skb)->cb)) | |
69 | ||
70 | ||
7eb95156 | 71 | static struct inet_frags ip6_frags; |
1da177e4 | 72 | |
f61944ef HX |
73 | static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev, |
74 | struct net_device *dev); | |
75 | ||
f6596f9d ZB |
76 | /* |
77 | * callers should be careful not to use the hash value outside the ipfrag_lock | |
78 | * as doing so could race with ipfrag_hash_rnd being recalculated. | |
79 | */ | |
93c8b90f IJ |
80 | unsigned int inet6_hash_frag(__be32 id, const struct in6_addr *saddr, |
81 | const struct in6_addr *daddr, u32 rnd) | |
1da177e4 | 82 | { |
82a39eb6 JK |
83 | u32 c; |
84 | ||
8064b3cf ED |
85 | c = jhash_3words(ipv6_addr_hash(saddr), ipv6_addr_hash(daddr), |
86 | (__force u32)id, rnd); | |
1da177e4 | 87 | |
7eb95156 | 88 | return c & (INETFRAGS_HASHSZ - 1); |
1da177e4 | 89 | } |
93c8b90f | 90 | EXPORT_SYMBOL_GPL(inet6_hash_frag); |
1da177e4 | 91 | |
321a3a99 | 92 | static unsigned int ip6_hashfn(struct inet_frag_queue *q) |
1da177e4 | 93 | { |
321a3a99 | 94 | struct frag_queue *fq; |
1da177e4 | 95 | |
321a3a99 | 96 | fq = container_of(q, struct frag_queue, q); |
93c8b90f | 97 | return inet6_hash_frag(fq->id, &fq->saddr, &fq->daddr, ip6_frags.rnd); |
1da177e4 LT |
98 | } |
99 | ||
cbc264ca | 100 | bool ip6_frag_match(struct inet_frag_queue *q, void *a) |
abd6523d PE |
101 | { |
102 | struct frag_queue *fq; | |
103 | struct ip6_create_arg *arg = a; | |
104 | ||
105 | fq = container_of(q, struct frag_queue, q); | |
cbc264ca ED |
106 | return fq->id == arg->id && |
107 | fq->user == arg->user && | |
108 | ipv6_addr_equal(&fq->saddr, arg->src) && | |
109 | ipv6_addr_equal(&fq->daddr, arg->dst); | |
abd6523d PE |
110 | } |
111 | EXPORT_SYMBOL(ip6_frag_match); | |
112 | ||
c6fda282 | 113 | void ip6_frag_init(struct inet_frag_queue *q, void *a) |
1da177e4 | 114 | { |
c6fda282 PE |
115 | struct frag_queue *fq = container_of(q, struct frag_queue, q); |
116 | struct ip6_create_arg *arg = a; | |
117 | ||
118 | fq->id = arg->id; | |
0b5ccb2e | 119 | fq->user = arg->user; |
4e3fd7a0 AD |
120 | fq->saddr = *arg->src; |
121 | fq->daddr = *arg->dst; | |
1da177e4 | 122 | } |
c6fda282 | 123 | EXPORT_SYMBOL(ip6_frag_init); |
1da177e4 | 124 | |
b836c99f AW |
125 | void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq, |
126 | struct inet_frags *frags) | |
1da177e4 | 127 | { |
a11d206d | 128 | struct net_device *dev = NULL; |
e521db9d | 129 | |
5ab11c98 | 130 | spin_lock(&fq->q.lock); |
1da177e4 | 131 | |
bc578a54 | 132 | if (fq->q.last_in & INET_FRAG_COMPLETE) |
1da177e4 LT |
133 | goto out; |
134 | ||
b836c99f | 135 | inet_frag_kill(&fq->q, frags); |
1da177e4 | 136 | |
69df9d59 ED |
137 | rcu_read_lock(); |
138 | dev = dev_get_by_index_rcu(net, fq->iif); | |
a11d206d | 139 | if (!dev) |
69df9d59 | 140 | goto out_rcu_unlock; |
a11d206d | 141 | |
483a47d2 DL |
142 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT); |
143 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS); | |
1da177e4 | 144 | |
78c784c4 | 145 | /* Don't send error if the first segment did not arrive. */ |
bc578a54 | 146 | if (!(fq->q.last_in & INET_FRAG_FIRST_IN) || !fq->q.fragments) |
69df9d59 | 147 | goto out_rcu_unlock; |
78c784c4 | 148 | |
78c784c4 IO |
149 | /* |
150 | But use as source device on which LAST ARRIVED | |
151 | segment was received. And do not use fq->dev | |
152 | pointer directly, device might already disappeared. | |
153 | */ | |
5ab11c98 | 154 | fq->q.fragments->dev = dev; |
3ffe533c | 155 | icmpv6_send(fq->q.fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0); |
69df9d59 ED |
156 | out_rcu_unlock: |
157 | rcu_read_unlock(); | |
1da177e4 | 158 | out: |
5ab11c98 | 159 | spin_unlock(&fq->q.lock); |
b836c99f AW |
160 | inet_frag_put(&fq->q, frags); |
161 | } | |
162 | EXPORT_SYMBOL(ip6_expire_frag_queue); | |
163 | ||
164 | static void ip6_frag_expire(unsigned long data) | |
165 | { | |
166 | struct frag_queue *fq; | |
167 | struct net *net; | |
168 | ||
169 | fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q); | |
170 | net = container_of(fq->q.net, struct net, ipv6.frags); | |
171 | ||
172 | ip6_expire_frag_queue(net, fq, &ip6_frags); | |
1da177e4 LT |
173 | } |
174 | ||
abd6523d | 175 | static __inline__ struct frag_queue * |
b71d1d42 | 176 | fq_find(struct net *net, __be32 id, const struct in6_addr *src, const struct in6_addr *dst) |
1da177e4 | 177 | { |
c6fda282 PE |
178 | struct inet_frag_queue *q; |
179 | struct ip6_create_arg arg; | |
abd6523d | 180 | unsigned int hash; |
1da177e4 | 181 | |
c6fda282 | 182 | arg.id = id; |
0b5ccb2e | 183 | arg.user = IP6_DEFRAG_LOCAL_DELIVER; |
c6fda282 PE |
184 | arg.src = src; |
185 | arg.dst = dst; | |
9a375803 PE |
186 | |
187 | read_lock(&ip6_frags.lock); | |
93c8b90f | 188 | hash = inet6_hash_frag(id, src, dst, ip6_frags.rnd); |
1da177e4 | 189 | |
ac18e750 | 190 | q = inet_frag_find(&net->ipv6.frags, &ip6_frags, &arg, hash); |
5a3da1fe HFS |
191 | if (IS_ERR_OR_NULL(q)) { |
192 | inet_frag_maybe_warn_overflow(q, pr_fmt()); | |
9546377c | 193 | return NULL; |
5a3da1fe | 194 | } |
c6fda282 | 195 | return container_of(q, struct frag_queue, q); |
1da177e4 LT |
196 | } |
197 | ||
f61944ef | 198 | static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, |
1da177e4 LT |
199 | struct frag_hdr *fhdr, int nhoff) |
200 | { | |
201 | struct sk_buff *prev, *next; | |
f61944ef | 202 | struct net_device *dev; |
1da177e4 | 203 | int offset, end; |
adf30907 | 204 | struct net *net = dev_net(skb_dst(skb)->dev); |
1da177e4 | 205 | |
bc578a54 | 206 | if (fq->q.last_in & INET_FRAG_COMPLETE) |
1da177e4 LT |
207 | goto err; |
208 | ||
209 | offset = ntohs(fhdr->frag_off) & ~0x7; | |
0660e03f ACM |
210 | end = offset + (ntohs(ipv6_hdr(skb)->payload_len) - |
211 | ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1))); | |
1da177e4 LT |
212 | |
213 | if ((unsigned int)end > IPV6_MAXPLEN) { | |
adf30907 | 214 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 215 | IPSTATS_MIB_INHDRERRORS); |
d56f90a7 ACM |
216 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
217 | ((u8 *)&fhdr->frag_off - | |
218 | skb_network_header(skb))); | |
f61944ef | 219 | return -1; |
1da177e4 LT |
220 | } |
221 | ||
d56f90a7 ACM |
222 | if (skb->ip_summed == CHECKSUM_COMPLETE) { |
223 | const unsigned char *nh = skb_network_header(skb); | |
1ab1457c | 224 | skb->csum = csum_sub(skb->csum, |
d56f90a7 ACM |
225 | csum_partial(nh, (u8 *)(fhdr + 1) - nh, |
226 | 0)); | |
227 | } | |
1da177e4 LT |
228 | |
229 | /* Is this the final fragment? */ | |
230 | if (!(fhdr->frag_off & htons(IP6_MF))) { | |
231 | /* If we already have some bits beyond end | |
232 | * or have different end, the segment is corrupted. | |
233 | */ | |
5ab11c98 | 234 | if (end < fq->q.len || |
bc578a54 | 235 | ((fq->q.last_in & INET_FRAG_LAST_IN) && end != fq->q.len)) |
1da177e4 | 236 | goto err; |
bc578a54 | 237 | fq->q.last_in |= INET_FRAG_LAST_IN; |
5ab11c98 | 238 | fq->q.len = end; |
1da177e4 LT |
239 | } else { |
240 | /* Check if the fragment is rounded to 8 bytes. | |
241 | * Required by the RFC. | |
242 | */ | |
243 | if (end & 0x7) { | |
244 | /* RFC2460 says always send parameter problem in | |
245 | * this case. -DaveM | |
246 | */ | |
adf30907 | 247 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 248 | IPSTATS_MIB_INHDRERRORS); |
1ab1457c | 249 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
1da177e4 | 250 | offsetof(struct ipv6hdr, payload_len)); |
f61944ef | 251 | return -1; |
1da177e4 | 252 | } |
5ab11c98 | 253 | if (end > fq->q.len) { |
1da177e4 | 254 | /* Some bits beyond end -> corruption. */ |
bc578a54 | 255 | if (fq->q.last_in & INET_FRAG_LAST_IN) |
1da177e4 | 256 | goto err; |
5ab11c98 | 257 | fq->q.len = end; |
1da177e4 LT |
258 | } |
259 | } | |
260 | ||
261 | if (end == offset) | |
262 | goto err; | |
263 | ||
264 | /* Point into the IP datagram 'data' part. */ | |
265 | if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) | |
266 | goto err; | |
1ab1457c | 267 | |
42ca89c1 SH |
268 | if (pskb_trim_rcsum(skb, end - offset)) |
269 | goto err; | |
1da177e4 LT |
270 | |
271 | /* Find out which fragments are in front and at the back of us | |
272 | * in the chain of fragments so far. We must know where to put | |
273 | * this fragment, right? | |
274 | */ | |
d6bebca9 CG |
275 | prev = fq->q.fragments_tail; |
276 | if (!prev || FRAG6_CB(prev)->offset < offset) { | |
277 | next = NULL; | |
278 | goto found; | |
279 | } | |
1da177e4 | 280 | prev = NULL; |
5ab11c98 | 281 | for(next = fq->q.fragments; next != NULL; next = next->next) { |
1da177e4 LT |
282 | if (FRAG6_CB(next)->offset >= offset) |
283 | break; /* bingo! */ | |
284 | prev = next; | |
285 | } | |
286 | ||
d6bebca9 | 287 | found: |
5de658f8 ED |
288 | /* RFC5722, Section 4, amended by Errata ID : 3089 |
289 | * When reassembling an IPv6 datagram, if | |
70789d70 ND |
290 | * one or more its constituent fragments is determined to be an |
291 | * overlapping fragment, the entire datagram (and any constituent | |
5de658f8 | 292 | * fragments) MUST be silently discarded. |
1da177e4 | 293 | */ |
1da177e4 | 294 | |
70789d70 ND |
295 | /* Check for overlap with preceding fragment. */ |
296 | if (prev && | |
f4642141 | 297 | (FRAG6_CB(prev)->offset + prev->len) > offset) |
70789d70 | 298 | goto discard_fq; |
1da177e4 | 299 | |
70789d70 ND |
300 | /* Look for overlap with succeeding segment. */ |
301 | if (next && FRAG6_CB(next)->offset < end) | |
302 | goto discard_fq; | |
1da177e4 LT |
303 | |
304 | FRAG6_CB(skb)->offset = offset; | |
305 | ||
306 | /* Insert this fragment in the chain of fragments. */ | |
307 | skb->next = next; | |
d6bebca9 CG |
308 | if (!next) |
309 | fq->q.fragments_tail = skb; | |
1da177e4 LT |
310 | if (prev) |
311 | prev->next = skb; | |
312 | else | |
5ab11c98 | 313 | fq->q.fragments = skb; |
1da177e4 | 314 | |
f61944ef HX |
315 | dev = skb->dev; |
316 | if (dev) { | |
317 | fq->iif = dev->ifindex; | |
318 | skb->dev = NULL; | |
319 | } | |
5ab11c98 PE |
320 | fq->q.stamp = skb->tstamp; |
321 | fq->q.meat += skb->len; | |
d433673e | 322 | add_frag_mem_limit(&fq->q, skb->truesize); |
1da177e4 LT |
323 | |
324 | /* The first fragment. | |
325 | * nhoffset is obtained from the first fragment, of course. | |
326 | */ | |
327 | if (offset == 0) { | |
328 | fq->nhoffset = nhoff; | |
bc578a54 | 329 | fq->q.last_in |= INET_FRAG_FIRST_IN; |
1da177e4 | 330 | } |
f61944ef | 331 | |
bc578a54 JP |
332 | if (fq->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && |
333 | fq->q.meat == fq->q.len) | |
f61944ef HX |
334 | return ip6_frag_reasm(fq, prev, dev); |
335 | ||
3ef0eb0d | 336 | inet_frag_lru_move(&fq->q); |
f61944ef | 337 | return -1; |
1da177e4 | 338 | |
70789d70 | 339 | discard_fq: |
b836c99f | 340 | inet_frag_kill(&fq->q, &ip6_frags); |
1da177e4 | 341 | err: |
adf30907 | 342 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
3bd653c8 | 343 | IPSTATS_MIB_REASMFAILS); |
1da177e4 | 344 | kfree_skb(skb); |
f61944ef | 345 | return -1; |
1da177e4 LT |
346 | } |
347 | ||
348 | /* | |
349 | * Check if this packet is complete. | |
350 | * Returns NULL on failure by any reason, and pointer | |
351 | * to current nexthdr field in reassembled frame. | |
352 | * | |
353 | * It is called with locked fq, and caller must check that | |
354 | * queue is eligible for reassembly i.e. it is not COMPLETE, | |
355 | * the last and the first frames arrived and all the bits are here. | |
356 | */ | |
f61944ef | 357 | static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev, |
1da177e4 LT |
358 | struct net_device *dev) |
359 | { | |
2bad35b7 | 360 | struct net *net = container_of(fq->q.net, struct net, ipv6.frags); |
5ab11c98 | 361 | struct sk_buff *fp, *head = fq->q.fragments; |
1da177e4 LT |
362 | int payload_len; |
363 | unsigned int nhoff; | |
ec16439e | 364 | int sum_truesize; |
1da177e4 | 365 | |
b836c99f | 366 | inet_frag_kill(&fq->q, &ip6_frags); |
1da177e4 | 367 | |
f61944ef HX |
368 | /* Make the one we just received the head. */ |
369 | if (prev) { | |
370 | head = prev->next; | |
371 | fp = skb_clone(head, GFP_ATOMIC); | |
372 | ||
373 | if (!fp) | |
374 | goto out_oom; | |
375 | ||
376 | fp->next = head->next; | |
d6bebca9 CG |
377 | if (!fp->next) |
378 | fq->q.fragments_tail = fp; | |
f61944ef HX |
379 | prev->next = fp; |
380 | ||
5ab11c98 PE |
381 | skb_morph(head, fq->q.fragments); |
382 | head->next = fq->q.fragments->next; | |
f61944ef | 383 | |
808db80a | 384 | consume_skb(fq->q.fragments); |
5ab11c98 | 385 | fq->q.fragments = head; |
f61944ef HX |
386 | } |
387 | ||
547b792c IJ |
388 | WARN_ON(head == NULL); |
389 | WARN_ON(FRAG6_CB(head)->offset != 0); | |
1da177e4 LT |
390 | |
391 | /* Unfragmented part is taken from the first segment. */ | |
d56f90a7 | 392 | payload_len = ((head->data - skb_network_header(head)) - |
5ab11c98 | 393 | sizeof(struct ipv6hdr) + fq->q.len - |
d56f90a7 | 394 | sizeof(struct frag_hdr)); |
1da177e4 LT |
395 | if (payload_len > IPV6_MAXPLEN) |
396 | goto out_oversize; | |
397 | ||
398 | /* Head of list must not be cloned. */ | |
14bbd6a5 | 399 | if (skb_unclone(head, GFP_ATOMIC)) |
1da177e4 LT |
400 | goto out_oom; |
401 | ||
402 | /* If the first fragment is fragmented itself, we split | |
403 | * it to two chunks: the first with data and paged part | |
404 | * and the second, holding only fragments. */ | |
21dc3301 | 405 | if (skb_has_frag_list(head)) { |
1da177e4 LT |
406 | struct sk_buff *clone; |
407 | int i, plen = 0; | |
408 | ||
409 | if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) | |
410 | goto out_oom; | |
411 | clone->next = head->next; | |
412 | head->next = clone; | |
413 | skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; | |
4d9092bb | 414 | skb_frag_list_init(head); |
9e903e08 ED |
415 | for (i = 0; i < skb_shinfo(head)->nr_frags; i++) |
416 | plen += skb_frag_size(&skb_shinfo(head)->frags[i]); | |
1da177e4 LT |
417 | clone->len = clone->data_len = head->data_len - plen; |
418 | head->data_len -= clone->len; | |
419 | head->len -= clone->len; | |
420 | clone->csum = 0; | |
421 | clone->ip_summed = head->ip_summed; | |
d433673e | 422 | add_frag_mem_limit(&fq->q, clone->truesize); |
1da177e4 LT |
423 | } |
424 | ||
425 | /* We have to remove fragment header from datagram and to relocate | |
426 | * header in order to calculate ICV correctly. */ | |
427 | nhoff = fq->nhoffset; | |
b0e380b1 | 428 | skb_network_header(head)[nhoff] = skb_transport_header(head)[0]; |
1ab1457c | 429 | memmove(head->head + sizeof(struct frag_hdr), head->head, |
1da177e4 | 430 | (head->data - head->head) - sizeof(struct frag_hdr)); |
b0e380b1 ACM |
431 | head->mac_header += sizeof(struct frag_hdr); |
432 | head->network_header += sizeof(struct frag_hdr); | |
1da177e4 | 433 | |
badff6d0 | 434 | skb_reset_transport_header(head); |
d56f90a7 | 435 | skb_push(head, head->data - skb_network_header(head)); |
1da177e4 | 436 | |
ec16439e ED |
437 | sum_truesize = head->truesize; |
438 | for (fp = head->next; fp;) { | |
439 | bool headstolen; | |
440 | int delta; | |
441 | struct sk_buff *next = fp->next; | |
442 | ||
443 | sum_truesize += fp->truesize; | |
1da177e4 LT |
444 | if (head->ip_summed != fp->ip_summed) |
445 | head->ip_summed = CHECKSUM_NONE; | |
84fa7933 | 446 | else if (head->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 | 447 | head->csum = csum_add(head->csum, fp->csum); |
ec16439e ED |
448 | |
449 | if (skb_try_coalesce(head, fp, &headstolen, &delta)) { | |
450 | kfree_skb_partial(fp, headstolen); | |
451 | } else { | |
452 | if (!skb_shinfo(head)->frag_list) | |
453 | skb_shinfo(head)->frag_list = fp; | |
454 | head->data_len += fp->len; | |
455 | head->len += fp->len; | |
456 | head->truesize += fp->truesize; | |
457 | } | |
458 | fp = next; | |
1da177e4 | 459 | } |
d433673e | 460 | sub_frag_mem_limit(&fq->q, sum_truesize); |
1da177e4 LT |
461 | |
462 | head->next = NULL; | |
463 | head->dev = dev; | |
5ab11c98 | 464 | head->tstamp = fq->q.stamp; |
0660e03f | 465 | ipv6_hdr(head)->payload_len = htons(payload_len); |
951dbc8a | 466 | IP6CB(head)->nhoff = nhoff; |
1da177e4 | 467 | |
1da177e4 | 468 | /* Yes, and fold redundant checksum back. 8) */ |
84fa7933 | 469 | if (head->ip_summed == CHECKSUM_COMPLETE) |
d56f90a7 | 470 | head->csum = csum_partial(skb_network_header(head), |
cfe1fc77 | 471 | skb_network_header_len(head), |
d56f90a7 | 472 | head->csum); |
1da177e4 | 473 | |
a11d206d | 474 | rcu_read_lock(); |
2bad35b7 | 475 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMOKS); |
a11d206d | 476 | rcu_read_unlock(); |
5ab11c98 | 477 | fq->q.fragments = NULL; |
d6bebca9 | 478 | fq->q.fragments_tail = NULL; |
1da177e4 LT |
479 | return 1; |
480 | ||
481 | out_oversize: | |
e87cc472 | 482 | net_dbg_ratelimited("ip6_frag_reasm: payload len = %d\n", payload_len); |
1da177e4 LT |
483 | goto out_fail; |
484 | out_oom: | |
e87cc472 | 485 | net_dbg_ratelimited("ip6_frag_reasm: no memory for reassembly\n"); |
1da177e4 | 486 | out_fail: |
a11d206d | 487 | rcu_read_lock(); |
2bad35b7 | 488 | IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS); |
a11d206d | 489 | rcu_read_unlock(); |
1da177e4 LT |
490 | return -1; |
491 | } | |
492 | ||
e5bbef20 | 493 | static int ipv6_frag_rcv(struct sk_buff *skb) |
1da177e4 | 494 | { |
1da177e4 LT |
495 | struct frag_hdr *fhdr; |
496 | struct frag_queue *fq; | |
b71d1d42 | 497 | const struct ipv6hdr *hdr = ipv6_hdr(skb); |
adf30907 | 498 | struct net *net = dev_net(skb_dst(skb)->dev); |
6b102865 | 499 | int evicted; |
1da177e4 | 500 | |
adf30907 | 501 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMREQDS); |
1da177e4 LT |
502 | |
503 | /* Jumbo payload inhibits frag. header */ | |
98b3377c DL |
504 | if (hdr->payload_len==0) |
505 | goto fail_hdr; | |
506 | ||
ea2ae17d | 507 | if (!pskb_may_pull(skb, (skb_transport_offset(skb) + |
98b3377c DL |
508 | sizeof(struct frag_hdr)))) |
509 | goto fail_hdr; | |
1da177e4 | 510 | |
0660e03f | 511 | hdr = ipv6_hdr(skb); |
9c70220b | 512 | fhdr = (struct frag_hdr *)skb_transport_header(skb); |
1da177e4 LT |
513 | |
514 | if (!(fhdr->frag_off & htons(0xFFF9))) { | |
515 | /* It is not a fragmented frame */ | |
b0e380b1 | 516 | skb->transport_header += sizeof(struct frag_hdr); |
483a47d2 | 517 | IP6_INC_STATS_BH(net, |
adf30907 | 518 | ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMOKS); |
1da177e4 | 519 | |
d56f90a7 | 520 | IP6CB(skb)->nhoff = (u8 *)fhdr - skb_network_header(skb); |
1da177e4 LT |
521 | return 1; |
522 | } | |
523 | ||
6b102865 AW |
524 | evicted = inet_frag_evictor(&net->ipv6.frags, &ip6_frags, false); |
525 | if (evicted) | |
526 | IP6_ADD_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), | |
527 | IPSTATS_MIB_REASMFAILS, evicted); | |
1da177e4 | 528 | |
9546377c SW |
529 | fq = fq_find(net, fhdr->identification, &hdr->saddr, &hdr->daddr); |
530 | if (fq != NULL) { | |
f61944ef | 531 | int ret; |
1da177e4 | 532 | |
5ab11c98 | 533 | spin_lock(&fq->q.lock); |
1da177e4 | 534 | |
f61944ef | 535 | ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff); |
1da177e4 | 536 | |
5ab11c98 | 537 | spin_unlock(&fq->q.lock); |
b836c99f | 538 | inet_frag_put(&fq->q, &ip6_frags); |
1da177e4 LT |
539 | return ret; |
540 | } | |
541 | ||
adf30907 | 542 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMFAILS); |
1da177e4 LT |
543 | kfree_skb(skb); |
544 | return -1; | |
98b3377c DL |
545 | |
546 | fail_hdr: | |
adf30907 | 547 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); |
98b3377c DL |
548 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb_network_header_len(skb)); |
549 | return -1; | |
1da177e4 LT |
550 | } |
551 | ||
41135cc8 | 552 | static const struct inet6_protocol frag_protocol = |
1da177e4 LT |
553 | { |
554 | .handler = ipv6_frag_rcv, | |
555 | .flags = INET6_PROTO_NOPOLICY, | |
556 | }; | |
557 | ||
8d8354d2 | 558 | #ifdef CONFIG_SYSCTL |
0a64b4b8 | 559 | static struct ctl_table ip6_frags_ns_ctl_table[] = { |
8d8354d2 | 560 | { |
8d8354d2 | 561 | .procname = "ip6frag_high_thresh", |
e31e0bdc | 562 | .data = &init_net.ipv6.frags.high_thresh, |
8d8354d2 PE |
563 | .maxlen = sizeof(int), |
564 | .mode = 0644, | |
6d9f239a | 565 | .proc_handler = proc_dointvec |
8d8354d2 PE |
566 | }, |
567 | { | |
8d8354d2 | 568 | .procname = "ip6frag_low_thresh", |
e31e0bdc | 569 | .data = &init_net.ipv6.frags.low_thresh, |
8d8354d2 PE |
570 | .maxlen = sizeof(int), |
571 | .mode = 0644, | |
6d9f239a | 572 | .proc_handler = proc_dointvec |
8d8354d2 PE |
573 | }, |
574 | { | |
8d8354d2 | 575 | .procname = "ip6frag_time", |
b2fd5321 | 576 | .data = &init_net.ipv6.frags.timeout, |
8d8354d2 PE |
577 | .maxlen = sizeof(int), |
578 | .mode = 0644, | |
6d9f239a | 579 | .proc_handler = proc_dointvec_jiffies, |
8d8354d2 | 580 | }, |
7d291ebb PE |
581 | { } |
582 | }; | |
583 | ||
584 | static struct ctl_table ip6_frags_ctl_table[] = { | |
8d8354d2 | 585 | { |
8d8354d2 | 586 | .procname = "ip6frag_secret_interval", |
3b4bc4a2 | 587 | .data = &ip6_frags.secret_interval, |
8d8354d2 PE |
588 | .maxlen = sizeof(int), |
589 | .mode = 0644, | |
6d9f239a | 590 | .proc_handler = proc_dointvec_jiffies, |
8d8354d2 PE |
591 | }, |
592 | { } | |
593 | }; | |
594 | ||
2c8c1e72 | 595 | static int __net_init ip6_frags_ns_sysctl_register(struct net *net) |
8d8354d2 | 596 | { |
e4a2d5c2 | 597 | struct ctl_table *table; |
8d8354d2 PE |
598 | struct ctl_table_header *hdr; |
599 | ||
0a64b4b8 | 600 | table = ip6_frags_ns_ctl_table; |
09ad9bc7 | 601 | if (!net_eq(net, &init_net)) { |
0a64b4b8 | 602 | table = kmemdup(table, sizeof(ip6_frags_ns_ctl_table), GFP_KERNEL); |
e4a2d5c2 PE |
603 | if (table == NULL) |
604 | goto err_alloc; | |
605 | ||
e31e0bdc PE |
606 | table[0].data = &net->ipv6.frags.high_thresh; |
607 | table[1].data = &net->ipv6.frags.low_thresh; | |
b2fd5321 | 608 | table[2].data = &net->ipv6.frags.timeout; |
464dc801 EB |
609 | |
610 | /* Don't export sysctls to unprivileged users */ | |
611 | if (net->user_ns != &init_user_ns) | |
612 | table[0].procname = NULL; | |
e4a2d5c2 PE |
613 | } |
614 | ||
ec8f23ce | 615 | hdr = register_net_sysctl(net, "net/ipv6", table); |
e4a2d5c2 PE |
616 | if (hdr == NULL) |
617 | goto err_reg; | |
618 | ||
619 | net->ipv6.sysctl.frags_hdr = hdr; | |
620 | return 0; | |
621 | ||
622 | err_reg: | |
09ad9bc7 | 623 | if (!net_eq(net, &init_net)) |
e4a2d5c2 PE |
624 | kfree(table); |
625 | err_alloc: | |
626 | return -ENOMEM; | |
627 | } | |
628 | ||
2c8c1e72 | 629 | static void __net_exit ip6_frags_ns_sysctl_unregister(struct net *net) |
e4a2d5c2 PE |
630 | { |
631 | struct ctl_table *table; | |
632 | ||
633 | table = net->ipv6.sysctl.frags_hdr->ctl_table_arg; | |
634 | unregister_net_sysctl_table(net->ipv6.sysctl.frags_hdr); | |
3705e11a YH |
635 | if (!net_eq(net, &init_net)) |
636 | kfree(table); | |
8d8354d2 | 637 | } |
7d291ebb PE |
638 | |
639 | static struct ctl_table_header *ip6_ctl_header; | |
640 | ||
641 | static int ip6_frags_sysctl_register(void) | |
642 | { | |
43444757 | 643 | ip6_ctl_header = register_net_sysctl(&init_net, "net/ipv6", |
7d291ebb PE |
644 | ip6_frags_ctl_table); |
645 | return ip6_ctl_header == NULL ? -ENOMEM : 0; | |
646 | } | |
647 | ||
648 | static void ip6_frags_sysctl_unregister(void) | |
649 | { | |
650 | unregister_net_sysctl_table(ip6_ctl_header); | |
651 | } | |
8d8354d2 | 652 | #else |
0a64b4b8 | 653 | static inline int ip6_frags_ns_sysctl_register(struct net *net) |
e71e0349 | 654 | { |
8d8354d2 PE |
655 | return 0; |
656 | } | |
e4a2d5c2 | 657 | |
0a64b4b8 | 658 | static inline void ip6_frags_ns_sysctl_unregister(struct net *net) |
e4a2d5c2 PE |
659 | { |
660 | } | |
7d291ebb PE |
661 | |
662 | static inline int ip6_frags_sysctl_register(void) | |
663 | { | |
664 | return 0; | |
665 | } | |
666 | ||
667 | static inline void ip6_frags_sysctl_unregister(void) | |
668 | { | |
669 | } | |
8d8354d2 | 670 | #endif |
7d460db9 | 671 | |
2c8c1e72 | 672 | static int __net_init ipv6_frags_init_net(struct net *net) |
8d8354d2 | 673 | { |
7c070aa9 SW |
674 | net->ipv6.frags.high_thresh = IPV6_FRAG_HIGH_THRESH; |
675 | net->ipv6.frags.low_thresh = IPV6_FRAG_LOW_THRESH; | |
b2fd5321 | 676 | net->ipv6.frags.timeout = IPV6_FRAG_TIMEOUT; |
8d8354d2 | 677 | |
e5a2bb84 PE |
678 | inet_frags_init_net(&net->ipv6.frags); |
679 | ||
0a64b4b8 | 680 | return ip6_frags_ns_sysctl_register(net); |
e71e0349 DL |
681 | } |
682 | ||
2c8c1e72 | 683 | static void __net_exit ipv6_frags_exit_net(struct net *net) |
81566e83 | 684 | { |
0a64b4b8 | 685 | ip6_frags_ns_sysctl_unregister(net); |
81566e83 PE |
686 | inet_frags_exit_net(&net->ipv6.frags, &ip6_frags); |
687 | } | |
688 | ||
689 | static struct pernet_operations ip6_frags_ops = { | |
690 | .init = ipv6_frags_init_net, | |
691 | .exit = ipv6_frags_exit_net, | |
692 | }; | |
693 | ||
853cbbaa | 694 | int __init ipv6_frag_init(void) |
1da177e4 | 695 | { |
853cbbaa | 696 | int ret; |
1da177e4 | 697 | |
853cbbaa DL |
698 | ret = inet6_add_protocol(&frag_protocol, IPPROTO_FRAGMENT); |
699 | if (ret) | |
700 | goto out; | |
e71e0349 | 701 | |
7d291ebb PE |
702 | ret = ip6_frags_sysctl_register(); |
703 | if (ret) | |
704 | goto err_sysctl; | |
705 | ||
0002c630 PE |
706 | ret = register_pernet_subsys(&ip6_frags_ops); |
707 | if (ret) | |
708 | goto err_pernet; | |
8d8354d2 | 709 | |
321a3a99 | 710 | ip6_frags.hashfn = ip6_hashfn; |
c6fda282 | 711 | ip6_frags.constructor = ip6_frag_init; |
c9547709 | 712 | ip6_frags.destructor = NULL; |
1e4b8287 PE |
713 | ip6_frags.skb_free = NULL; |
714 | ip6_frags.qsize = sizeof(struct frag_queue); | |
abd6523d | 715 | ip6_frags.match = ip6_frag_match; |
e521db9d | 716 | ip6_frags.frag_expire = ip6_frag_expire; |
3b4bc4a2 | 717 | ip6_frags.secret_interval = 10 * 60 * HZ; |
7eb95156 | 718 | inet_frags_init(&ip6_frags); |
853cbbaa DL |
719 | out: |
720 | return ret; | |
0002c630 PE |
721 | |
722 | err_pernet: | |
7d291ebb PE |
723 | ip6_frags_sysctl_unregister(); |
724 | err_sysctl: | |
0002c630 PE |
725 | inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT); |
726 | goto out; | |
853cbbaa DL |
727 | } |
728 | ||
729 | void ipv6_frag_exit(void) | |
730 | { | |
731 | inet_frags_fini(&ip6_frags); | |
7d291ebb | 732 | ip6_frags_sysctl_unregister(); |
81566e83 | 733 | unregister_pernet_subsys(&ip6_frags_ops); |
853cbbaa | 734 | inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT); |
1da177e4 | 735 | } |