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1 /*
2 * Copyright (c) 2007-2012 Nicira, Inc.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of version 2 of the GNU General Public
6 * License as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
16 * 02110-1301, USA
17 */
18
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20
21 #include <linux/if_arp.h>
22 #include <linux/if_ether.h>
23 #include <linux/ip.h>
24 #include <linux/if_vlan.h>
25 #include <linux/igmp.h>
26 #include <linux/in.h>
27 #include <linux/in_route.h>
28 #include <linux/inetdevice.h>
29 #include <linux/jhash.h>
30 #include <linux/list.h>
31 #include <linux/kernel.h>
32 #include <linux/version.h>
33 #include <linux/workqueue.h>
34 #include <linux/rculist.h>
35
36 #include <net/dsfield.h>
37 #include <net/dst.h>
38 #include <net/icmp.h>
39 #include <net/inet_ecn.h>
40 #include <net/ip.h>
41 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
42 #include <net/ipv6.h>
43 #endif
44 #include <net/route.h>
45 #include <net/xfrm.h>
46
47 #include "checksum.h"
48 #include "datapath.h"
49 #include "tunnel.h"
50 #include "vlan.h"
51 #include "vport.h"
52 #include "vport-generic.h"
53 #include "vport-internal_dev.h"
54
55 #ifdef NEED_CACHE_TIMEOUT
56 /*
57 * On kernels where we can't quickly detect changes in the rest of the system
58 * we use an expiration time to invalidate the cache. A shorter expiration
59 * reduces the length of time that we may potentially blackhole packets while
60 * a longer time increases performance by reducing the frequency that the
61 * cache needs to be rebuilt. A variety of factors may cause the cache to be
62 * invalidated before the expiration time but this is the maximum. The time
63 * is expressed in jiffies.
64 */
65 #define MAX_CACHE_EXP HZ
66 #endif
67
68 /*
69 * Interval to check for and remove caches that are no longer valid. Caches
70 * are checked for validity before they are used for packet encapsulation and
71 * old caches are removed at that time. However, if no packets are sent through
72 * the tunnel then the cache will never be destroyed. Since it holds
73 * references to a number of system objects, the cache will continue to use
74 * system resources by not allowing those objects to be destroyed. The cache
75 * cleaner is periodically run to free invalid caches. It does not
76 * significantly affect system performance. A lower interval will release
77 * resources faster but will itself consume resources by requiring more frequent
78 * checks. A longer interval may result in messages being printed to the kernel
79 * message buffer about unreleased resources. The interval is expressed in
80 * jiffies.
81 */
82 #define CACHE_CLEANER_INTERVAL (5 * HZ)
83
84 #define CACHE_DATA_ALIGN 16
85 #define PORT_TABLE_SIZE 1024
86
87 static struct hlist_head *port_table __read_mostly;
88 static int port_table_count;
89
90 static void cache_cleaner(struct work_struct *work);
91 static DECLARE_DELAYED_WORK(cache_cleaner_wq, cache_cleaner);
92
93 /*
94 * These are just used as an optimization: they don't require any kind of
95 * synchronization because we could have just as easily read the value before
96 * the port change happened.
97 */
98 static unsigned int key_local_remote_ports __read_mostly;
99 static unsigned int key_remote_ports __read_mostly;
100 static unsigned int key_multicast_ports __read_mostly;
101 static unsigned int local_remote_ports __read_mostly;
102 static unsigned int remote_ports __read_mostly;
103 static unsigned int null_ports __read_mostly;
104 static unsigned int multicast_ports __read_mostly;
105
106 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,36)
107 #define rt_dst(rt) (rt->dst)
108 #else
109 #define rt_dst(rt) (rt->u.dst)
110 #endif
111
112 #if LINUX_VERSION_CODE >= KERNEL_VERSION(3,1,0)
113 static struct hh_cache *rt_hh(struct rtable *rt)
114 {
115 struct neighbour *neigh = dst_get_neighbour_noref(&rt->dst);
116 if (!neigh || !(neigh->nud_state & NUD_CONNECTED) ||
117 !neigh->hh.hh_len)
118 return NULL;
119 return &neigh->hh;
120 }
121 #else
122 #define rt_hh(rt) (rt_dst(rt).hh)
123 #endif
124
125 static struct vport *tnl_vport_to_vport(const struct tnl_vport *tnl_vport)
126 {
127 return vport_from_priv(tnl_vport);
128 }
129
130 /* This is analogous to rtnl_dereference for the tunnel cache. It checks that
131 * cache_lock is held, so it is only for update side code.
132 */
133 static struct tnl_cache *cache_dereference(struct tnl_vport *tnl_vport)
134 {
135 return rcu_dereference_protected(tnl_vport->cache,
136 lockdep_is_held(&tnl_vport->cache_lock));
137 }
138
139 static void schedule_cache_cleaner(void)
140 {
141 schedule_delayed_work(&cache_cleaner_wq, CACHE_CLEANER_INTERVAL);
142 }
143
144 static void free_cache(struct tnl_cache *cache)
145 {
146 if (!cache)
147 return;
148
149 ovs_flow_put(cache->flow);
150 ip_rt_put(cache->rt);
151 kfree(cache);
152 }
153
154 static void free_config_rcu(struct rcu_head *rcu)
155 {
156 struct tnl_mutable_config *c = container_of(rcu, struct tnl_mutable_config, rcu);
157 kfree(c);
158 }
159
160 static void free_cache_rcu(struct rcu_head *rcu)
161 {
162 struct tnl_cache *c = container_of(rcu, struct tnl_cache, rcu);
163 free_cache(c);
164 }
165
166 /* Frees the portion of 'mutable' that requires RTNL and thus can't happen
167 * within an RCU callback. Fortunately this part doesn't require waiting for
168 * an RCU grace period.
169 */
170 static void free_mutable_rtnl(struct tnl_mutable_config *mutable)
171 {
172 ASSERT_RTNL();
173 if (ipv4_is_multicast(mutable->key.daddr) && mutable->mlink) {
174 struct in_device *in_dev;
175 in_dev = inetdev_by_index(port_key_get_net(&mutable->key), mutable->mlink);
176 if (in_dev)
177 ip_mc_dec_group(in_dev, mutable->key.daddr);
178 }
179 }
180
181 static void assign_config_rcu(struct vport *vport,
182 struct tnl_mutable_config *new_config)
183 {
184 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
185 struct tnl_mutable_config *old_config;
186
187 old_config = rtnl_dereference(tnl_vport->mutable);
188 rcu_assign_pointer(tnl_vport->mutable, new_config);
189
190 free_mutable_rtnl(old_config);
191 call_rcu(&old_config->rcu, free_config_rcu);
192 }
193
194 static void assign_cache_rcu(struct vport *vport, struct tnl_cache *new_cache)
195 {
196 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
197 struct tnl_cache *old_cache;
198
199 old_cache = cache_dereference(tnl_vport);
200 rcu_assign_pointer(tnl_vport->cache, new_cache);
201
202 if (old_cache)
203 call_rcu(&old_cache->rcu, free_cache_rcu);
204 }
205
206 static unsigned int *find_port_pool(const struct tnl_mutable_config *mutable)
207 {
208 bool is_multicast = ipv4_is_multicast(mutable->key.daddr);
209
210 if (mutable->flags & TNL_F_IN_KEY_MATCH) {
211 if (mutable->key.saddr)
212 return &local_remote_ports;
213 else if (is_multicast)
214 return &multicast_ports;
215 else
216 return &remote_ports;
217 } else {
218 if (mutable->key.saddr)
219 return &key_local_remote_ports;
220 else if (is_multicast)
221 return &key_multicast_ports;
222 else if (mutable->key.daddr)
223 return &key_remote_ports;
224 else
225 return &null_ports;
226 }
227 }
228
229 static u32 port_hash(const struct port_lookup_key *key)
230 {
231 return jhash2((u32 *)key, (PORT_KEY_LEN / sizeof(u32)), 0);
232 }
233
234 static struct hlist_head *find_bucket(u32 hash)
235 {
236 return &port_table[(hash & (PORT_TABLE_SIZE - 1))];
237 }
238
239 static void port_table_add_port(struct vport *vport)
240 {
241 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
242 const struct tnl_mutable_config *mutable;
243 u32 hash;
244
245 if (port_table_count == 0)
246 schedule_cache_cleaner();
247
248 mutable = rtnl_dereference(tnl_vport->mutable);
249 hash = port_hash(&mutable->key);
250 hlist_add_head_rcu(&tnl_vport->hash_node, find_bucket(hash));
251 port_table_count++;
252
253 (*find_port_pool(rtnl_dereference(tnl_vport->mutable)))++;
254 }
255
256 static void port_table_move_port(struct vport *vport,
257 struct tnl_mutable_config *new_mutable)
258 {
259 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
260 u32 hash;
261
262 hash = port_hash(&new_mutable->key);
263 hlist_del_init_rcu(&tnl_vport->hash_node);
264 hlist_add_head_rcu(&tnl_vport->hash_node, find_bucket(hash));
265
266 (*find_port_pool(rtnl_dereference(tnl_vport->mutable)))--;
267 assign_config_rcu(vport, new_mutable);
268 (*find_port_pool(rtnl_dereference(tnl_vport->mutable)))++;
269 }
270
271 static void port_table_remove_port(struct vport *vport)
272 {
273 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
274
275 hlist_del_init_rcu(&tnl_vport->hash_node);
276
277 port_table_count--;
278 if (port_table_count == 0)
279 cancel_delayed_work_sync(&cache_cleaner_wq);
280
281 (*find_port_pool(rtnl_dereference(tnl_vport->mutable)))--;
282 }
283
284 static struct vport *port_table_lookup(struct port_lookup_key *key,
285 const struct tnl_mutable_config **pmutable)
286 {
287 struct hlist_node *n;
288 struct hlist_head *bucket;
289 u32 hash = port_hash(key);
290 struct tnl_vport *tnl_vport;
291
292 bucket = find_bucket(hash);
293
294 hlist_for_each_entry_rcu(tnl_vport, n, bucket, hash_node) {
295 struct tnl_mutable_config *mutable;
296
297 mutable = rcu_dereference_rtnl(tnl_vport->mutable);
298 if (!memcmp(&mutable->key, key, PORT_KEY_LEN)) {
299 *pmutable = mutable;
300 return tnl_vport_to_vport(tnl_vport);
301 }
302 }
303
304 return NULL;
305 }
306
307 struct vport *ovs_tnl_find_port(struct net *net, __be32 saddr, __be32 daddr,
308 __be64 key, int tunnel_type,
309 const struct tnl_mutable_config **mutable)
310 {
311 struct port_lookup_key lookup;
312 struct vport *vport;
313 bool is_multicast = ipv4_is_multicast(saddr);
314
315 port_key_set_net(&lookup, net);
316 lookup.saddr = saddr;
317 lookup.daddr = daddr;
318
319 /* First try for exact match on in_key. */
320 lookup.in_key = key;
321 lookup.tunnel_type = tunnel_type | TNL_T_KEY_EXACT;
322 if (!is_multicast && key_local_remote_ports) {
323 vport = port_table_lookup(&lookup, mutable);
324 if (vport)
325 return vport;
326 }
327 if (key_remote_ports) {
328 lookup.saddr = 0;
329 vport = port_table_lookup(&lookup, mutable);
330 if (vport)
331 return vport;
332
333 lookup.saddr = saddr;
334 }
335
336 /* Then try matches that wildcard in_key. */
337 lookup.in_key = 0;
338 lookup.tunnel_type = tunnel_type | TNL_T_KEY_MATCH;
339 if (!is_multicast && local_remote_ports) {
340 vport = port_table_lookup(&lookup, mutable);
341 if (vport)
342 return vport;
343 }
344 if (remote_ports) {
345 lookup.saddr = 0;
346 vport = port_table_lookup(&lookup, mutable);
347 if (vport)
348 return vport;
349 }
350
351 if (is_multicast) {
352 lookup.saddr = 0;
353 lookup.daddr = saddr;
354 if (key_multicast_ports) {
355 lookup.tunnel_type = tunnel_type | TNL_T_KEY_EXACT;
356 lookup.in_key = key;
357 vport = port_table_lookup(&lookup, mutable);
358 if (vport)
359 return vport;
360 }
361 if (multicast_ports) {
362 lookup.tunnel_type = tunnel_type | TNL_T_KEY_MATCH;
363 lookup.in_key = 0;
364 vport = port_table_lookup(&lookup, mutable);
365 if (vport)
366 return vport;
367 }
368 }
369
370 if (null_ports) {
371 lookup.daddr = 0;
372 lookup.saddr = 0;
373 lookup.tunnel_type = tunnel_type;
374 vport = port_table_lookup(&lookup, mutable);
375 if (vport)
376 return vport;
377 }
378 return NULL;
379 }
380
381 static void ecn_decapsulate(struct sk_buff *skb)
382 {
383 if (unlikely(INET_ECN_is_ce(OVS_CB(skb)->tun_key->ipv4_tos))) {
384 __be16 protocol = skb->protocol;
385
386 skb_set_network_header(skb, ETH_HLEN);
387
388 if (protocol == htons(ETH_P_8021Q)) {
389 if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN)))
390 return;
391
392 protocol = vlan_eth_hdr(skb)->h_vlan_encapsulated_proto;
393 skb_set_network_header(skb, VLAN_ETH_HLEN);
394 }
395
396 if (protocol == htons(ETH_P_IP)) {
397 if (unlikely(!pskb_may_pull(skb, skb_network_offset(skb)
398 + sizeof(struct iphdr))))
399 return;
400
401 IP_ECN_set_ce(ip_hdr(skb));
402 }
403 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
404 else if (protocol == htons(ETH_P_IPV6)) {
405 if (unlikely(!pskb_may_pull(skb, skb_network_offset(skb)
406 + sizeof(struct ipv6hdr))))
407 return;
408
409 IP6_ECN_set_ce(ipv6_hdr(skb));
410 }
411 #endif
412 }
413 }
414
415 /**
416 * ovs_tnl_rcv - ingress point for generic tunnel code
417 *
418 * @vport: port this packet was received on
419 * @skb: received packet
420 * @tos: ToS from encapsulating IP packet, used to copy ECN bits
421 *
422 * Must be called with rcu_read_lock.
423 *
424 * Packets received by this function are in the following state:
425 * - skb->data points to the inner Ethernet header.
426 * - The inner Ethernet header is in the linear data area.
427 * - skb->csum does not include the inner Ethernet header.
428 * - The layer pointers are undefined.
429 */
430 void ovs_tnl_rcv(struct vport *vport, struct sk_buff *skb)
431 {
432 struct ethhdr *eh;
433
434 skb_reset_mac_header(skb);
435 eh = eth_hdr(skb);
436
437 if (likely(ntohs(eh->h_proto) >= 1536))
438 skb->protocol = eh->h_proto;
439 else
440 skb->protocol = htons(ETH_P_802_2);
441
442 skb_dst_drop(skb);
443 nf_reset(skb);
444 skb_clear_rxhash(skb);
445 secpath_reset(skb);
446
447 ecn_decapsulate(skb);
448 vlan_set_tci(skb, 0);
449
450 if (unlikely(compute_ip_summed(skb, false))) {
451 kfree_skb(skb);
452 return;
453 }
454
455 ovs_vport_receive(vport, skb);
456 }
457
458 static bool check_ipv4_address(__be32 addr)
459 {
460 if (ipv4_is_multicast(addr) || ipv4_is_lbcast(addr)
461 || ipv4_is_loopback(addr) || ipv4_is_zeronet(addr))
462 return false;
463
464 return true;
465 }
466
467 static bool ipv4_should_icmp(struct sk_buff *skb)
468 {
469 struct iphdr *old_iph = ip_hdr(skb);
470
471 /* Don't respond to L2 broadcast. */
472 if (is_multicast_ether_addr(eth_hdr(skb)->h_dest))
473 return false;
474
475 /* Don't respond to L3 broadcast or invalid addresses. */
476 if (!check_ipv4_address(old_iph->daddr) ||
477 !check_ipv4_address(old_iph->saddr))
478 return false;
479
480 /* Only respond to the first fragment. */
481 if (old_iph->frag_off & htons(IP_OFFSET))
482 return false;
483
484 /* Don't respond to ICMP error messages. */
485 if (old_iph->protocol == IPPROTO_ICMP) {
486 u8 icmp_type, *icmp_typep;
487
488 icmp_typep = skb_header_pointer(skb, (u8 *)old_iph +
489 (old_iph->ihl << 2) +
490 offsetof(struct icmphdr, type) -
491 skb->data, sizeof(icmp_type),
492 &icmp_type);
493
494 if (!icmp_typep)
495 return false;
496
497 if (*icmp_typep > NR_ICMP_TYPES
498 || (*icmp_typep <= ICMP_PARAMETERPROB
499 && *icmp_typep != ICMP_ECHOREPLY
500 && *icmp_typep != ICMP_ECHO))
501 return false;
502 }
503
504 return true;
505 }
506
507 static void ipv4_build_icmp(struct sk_buff *skb, struct sk_buff *nskb,
508 unsigned int mtu, unsigned int payload_length)
509 {
510 struct iphdr *iph, *old_iph = ip_hdr(skb);
511 struct icmphdr *icmph;
512 u8 *payload;
513
514 iph = (struct iphdr *)skb_put(nskb, sizeof(struct iphdr));
515 icmph = (struct icmphdr *)skb_put(nskb, sizeof(struct icmphdr));
516 payload = skb_put(nskb, payload_length);
517
518 /* IP */
519 iph->version = 4;
520 iph->ihl = sizeof(struct iphdr) >> 2;
521 iph->tos = (old_iph->tos & IPTOS_TOS_MASK) |
522 IPTOS_PREC_INTERNETCONTROL;
523 iph->tot_len = htons(sizeof(struct iphdr)
524 + sizeof(struct icmphdr)
525 + payload_length);
526 get_random_bytes(&iph->id, sizeof(iph->id));
527 iph->frag_off = 0;
528 iph->ttl = IPDEFTTL;
529 iph->protocol = IPPROTO_ICMP;
530 iph->daddr = old_iph->saddr;
531 iph->saddr = old_iph->daddr;
532
533 ip_send_check(iph);
534
535 /* ICMP */
536 icmph->type = ICMP_DEST_UNREACH;
537 icmph->code = ICMP_FRAG_NEEDED;
538 icmph->un.gateway = htonl(mtu);
539 icmph->checksum = 0;
540
541 nskb->csum = csum_partial((u8 *)icmph, sizeof(struct icmphdr), 0);
542 nskb->csum = skb_copy_and_csum_bits(skb, (u8 *)old_iph - skb->data,
543 payload, payload_length,
544 nskb->csum);
545 icmph->checksum = csum_fold(nskb->csum);
546 }
547
548 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
549 static bool ipv6_should_icmp(struct sk_buff *skb)
550 {
551 struct ipv6hdr *old_ipv6h = ipv6_hdr(skb);
552 int addr_type;
553 int payload_off = (u8 *)(old_ipv6h + 1) - skb->data;
554 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
555 __be16 frag_off;
556
557 /* Check source address is valid. */
558 addr_type = ipv6_addr_type(&old_ipv6h->saddr);
559 if (addr_type & IPV6_ADDR_MULTICAST || addr_type == IPV6_ADDR_ANY)
560 return false;
561
562 /* Don't reply to unspecified addresses. */
563 if (ipv6_addr_type(&old_ipv6h->daddr) == IPV6_ADDR_ANY)
564 return false;
565
566 /* Don't respond to ICMP error messages. */
567 payload_off = ipv6_skip_exthdr(skb, payload_off, &nexthdr, &frag_off);
568 if (payload_off < 0)
569 return false;
570
571 if (nexthdr == NEXTHDR_ICMP) {
572 u8 icmp_type, *icmp_typep;
573
574 icmp_typep = skb_header_pointer(skb, payload_off +
575 offsetof(struct icmp6hdr,
576 icmp6_type),
577 sizeof(icmp_type), &icmp_type);
578
579 if (!icmp_typep || !(*icmp_typep & ICMPV6_INFOMSG_MASK))
580 return false;
581 }
582
583 return true;
584 }
585
586 static void ipv6_build_icmp(struct sk_buff *skb, struct sk_buff *nskb,
587 unsigned int mtu, unsigned int payload_length)
588 {
589 struct ipv6hdr *ipv6h, *old_ipv6h = ipv6_hdr(skb);
590 struct icmp6hdr *icmp6h;
591 u8 *payload;
592
593 ipv6h = (struct ipv6hdr *)skb_put(nskb, sizeof(struct ipv6hdr));
594 icmp6h = (struct icmp6hdr *)skb_put(nskb, sizeof(struct icmp6hdr));
595 payload = skb_put(nskb, payload_length);
596
597 /* IPv6 */
598 ipv6h->version = 6;
599 ipv6h->priority = 0;
600 memset(&ipv6h->flow_lbl, 0, sizeof(ipv6h->flow_lbl));
601 ipv6h->payload_len = htons(sizeof(struct icmp6hdr)
602 + payload_length);
603 ipv6h->nexthdr = NEXTHDR_ICMP;
604 ipv6h->hop_limit = IPV6_DEFAULT_HOPLIMIT;
605 ipv6h->daddr = old_ipv6h->saddr;
606 ipv6h->saddr = old_ipv6h->daddr;
607
608 /* ICMPv6 */
609 icmp6h->icmp6_type = ICMPV6_PKT_TOOBIG;
610 icmp6h->icmp6_code = 0;
611 icmp6h->icmp6_cksum = 0;
612 icmp6h->icmp6_mtu = htonl(mtu);
613
614 nskb->csum = csum_partial((u8 *)icmp6h, sizeof(struct icmp6hdr), 0);
615 nskb->csum = skb_copy_and_csum_bits(skb, (u8 *)old_ipv6h - skb->data,
616 payload, payload_length,
617 nskb->csum);
618 icmp6h->icmp6_cksum = csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
619 sizeof(struct icmp6hdr)
620 + payload_length,
621 ipv6h->nexthdr, nskb->csum);
622 }
623 #endif /* IPv6 */
624
625 bool ovs_tnl_frag_needed(struct vport *vport,
626 const struct tnl_mutable_config *mutable,
627 struct sk_buff *skb, unsigned int mtu)
628 {
629 unsigned int eth_hdr_len = ETH_HLEN;
630 unsigned int total_length = 0, header_length = 0, payload_length;
631 struct ethhdr *eh, *old_eh = eth_hdr(skb);
632 struct sk_buff *nskb;
633
634 /* Sanity check */
635 if (skb->protocol == htons(ETH_P_IP)) {
636 if (mtu < IP_MIN_MTU)
637 return false;
638
639 if (!ipv4_should_icmp(skb))
640 return true;
641 }
642 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
643 else if (skb->protocol == htons(ETH_P_IPV6)) {
644 if (mtu < IPV6_MIN_MTU)
645 return false;
646
647 /*
648 * In theory we should do PMTUD on IPv6 multicast messages but
649 * we don't have an address to send from so just fragment.
650 */
651 if (ipv6_addr_type(&ipv6_hdr(skb)->daddr) & IPV6_ADDR_MULTICAST)
652 return false;
653
654 if (!ipv6_should_icmp(skb))
655 return true;
656 }
657 #endif
658 else
659 return false;
660
661 /* Allocate */
662 if (old_eh->h_proto == htons(ETH_P_8021Q))
663 eth_hdr_len = VLAN_ETH_HLEN;
664
665 payload_length = skb->len - eth_hdr_len;
666 if (skb->protocol == htons(ETH_P_IP)) {
667 header_length = sizeof(struct iphdr) + sizeof(struct icmphdr);
668 total_length = min_t(unsigned int, header_length +
669 payload_length, 576);
670 }
671 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
672 else {
673 header_length = sizeof(struct ipv6hdr) +
674 sizeof(struct icmp6hdr);
675 total_length = min_t(unsigned int, header_length +
676 payload_length, IPV6_MIN_MTU);
677 }
678 #endif
679
680 payload_length = total_length - header_length;
681
682 nskb = dev_alloc_skb(NET_IP_ALIGN + eth_hdr_len + header_length +
683 payload_length);
684 if (!nskb)
685 return false;
686
687 skb_reserve(nskb, NET_IP_ALIGN);
688
689 /* Ethernet / VLAN */
690 eh = (struct ethhdr *)skb_put(nskb, eth_hdr_len);
691 memcpy(eh->h_dest, old_eh->h_source, ETH_ALEN);
692 memcpy(eh->h_source, mutable->eth_addr, ETH_ALEN);
693 nskb->protocol = eh->h_proto = old_eh->h_proto;
694 if (old_eh->h_proto == htons(ETH_P_8021Q)) {
695 struct vlan_ethhdr *vh = (struct vlan_ethhdr *)eh;
696
697 vh->h_vlan_TCI = vlan_eth_hdr(skb)->h_vlan_TCI;
698 vh->h_vlan_encapsulated_proto = skb->protocol;
699 } else
700 vlan_set_tci(nskb, vlan_get_tci(skb));
701 skb_reset_mac_header(nskb);
702
703 /* Protocol */
704 if (skb->protocol == htons(ETH_P_IP))
705 ipv4_build_icmp(skb, nskb, mtu, payload_length);
706 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
707 else
708 ipv6_build_icmp(skb, nskb, mtu, payload_length);
709 #endif
710
711 if (unlikely(compute_ip_summed(nskb, false))) {
712 kfree_skb(nskb);
713 return false;
714 }
715
716 ovs_vport_receive(vport, nskb);
717
718 return true;
719 }
720
721 static bool check_mtu(struct sk_buff *skb,
722 struct vport *vport,
723 const struct tnl_mutable_config *mutable,
724 const struct rtable *rt, __be16 *frag_offp,
725 int tunnel_hlen)
726 {
727 bool df_inherit;
728 bool pmtud;
729 __be16 frag_off;
730 int mtu = 0;
731 unsigned int packet_length = skb->len - ETH_HLEN;
732
733 if (OVS_CB(skb)->tun_key->ipv4_dst) {
734 df_inherit = false;
735 pmtud = false;
736 frag_off = OVS_CB(skb)->tun_key->tun_flags & OVS_FLOW_TNL_F_DONT_FRAGMENT ?
737 htons(IP_DF) : 0;
738 } else {
739 df_inherit = mutable->flags & TNL_F_DF_INHERIT;
740 pmtud = mutable->flags & TNL_F_PMTUD;
741 frag_off = mutable->flags & TNL_F_DF_DEFAULT ? htons(IP_DF) : 0;
742 }
743
744 /* Allow for one level of tagging in the packet length. */
745 if (!vlan_tx_tag_present(skb) &&
746 eth_hdr(skb)->h_proto == htons(ETH_P_8021Q))
747 packet_length -= VLAN_HLEN;
748
749 if (pmtud) {
750 int vlan_header = 0;
751
752 /* The tag needs to go in packet regardless of where it
753 * currently is, so subtract it from the MTU.
754 */
755 if (vlan_tx_tag_present(skb) ||
756 eth_hdr(skb)->h_proto == htons(ETH_P_8021Q))
757 vlan_header = VLAN_HLEN;
758
759 mtu = dst_mtu(&rt_dst(rt))
760 - ETH_HLEN
761 - tunnel_hlen
762 - vlan_header;
763 }
764
765 if (skb->protocol == htons(ETH_P_IP)) {
766 struct iphdr *iph = ip_hdr(skb);
767
768 if (df_inherit)
769 frag_off = iph->frag_off & htons(IP_DF);
770
771 if (pmtud && iph->frag_off & htons(IP_DF)) {
772 mtu = max(mtu, IP_MIN_MTU);
773
774 if (packet_length > mtu &&
775 ovs_tnl_frag_needed(vport, mutable, skb, mtu))
776 return false;
777 }
778 }
779 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
780 else if (skb->protocol == htons(ETH_P_IPV6)) {
781 /* IPv6 requires end hosts to do fragmentation
782 * if the packet is above the minimum MTU.
783 */
784 if (df_inherit && packet_length > IPV6_MIN_MTU)
785 frag_off = htons(IP_DF);
786
787 if (pmtud) {
788 mtu = max(mtu, IPV6_MIN_MTU);
789
790 if (packet_length > mtu &&
791 ovs_tnl_frag_needed(vport, mutable, skb, mtu))
792 return false;
793 }
794 }
795 #endif
796
797 *frag_offp = frag_off;
798 return true;
799 }
800
801 static void create_tunnel_header(const struct vport *vport,
802 const struct tnl_mutable_config *mutable,
803 const struct ovs_key_ipv4_tunnel *tun_key,
804 const struct rtable *rt, void *header)
805 {
806 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
807 struct iphdr *iph = header;
808
809 iph->version = 4;
810 iph->ihl = sizeof(struct iphdr) >> 2;
811 iph->frag_off = htons(IP_DF);
812 iph->protocol = tnl_vport->tnl_ops->ipproto;
813 iph->tos = mutable->tos;
814 iph->daddr = rt->rt_dst;
815 iph->saddr = rt->rt_src;
816 iph->ttl = mutable->ttl;
817 if (!iph->ttl)
818 iph->ttl = ip4_dst_hoplimit(&rt_dst(rt));
819
820 tnl_vport->tnl_ops->build_header(vport, mutable, tun_key, iph + 1);
821 }
822
823 static void *get_cached_header(const struct tnl_cache *cache)
824 {
825 return (void *)cache + ALIGN(sizeof(struct tnl_cache), CACHE_DATA_ALIGN);
826 }
827
828 #ifdef HAVE_RT_GENID
829 static inline int rt_genid(struct net *net)
830 {
831 return atomic_read(&net->ipv4.rt_genid);
832 }
833 #endif
834
835 static bool check_cache_valid(const struct tnl_cache *cache,
836 const struct tnl_mutable_config *mutable)
837 {
838 struct hh_cache *hh;
839
840 if (!cache)
841 return false;
842
843 hh = rt_hh(cache->rt);
844 return hh &&
845 #ifdef NEED_CACHE_TIMEOUT
846 time_before(jiffies, cache->expiration) &&
847 #endif
848 #ifdef HAVE_RT_GENID
849 rt_genid(dev_net(rt_dst(cache->rt).dev)) == cache->rt->rt_genid &&
850 #endif
851 #ifdef HAVE_HH_SEQ
852 hh->hh_lock.sequence == cache->hh_seq &&
853 #endif
854 mutable->seq == cache->mutable_seq &&
855 (!ovs_is_internal_dev(rt_dst(cache->rt).dev) ||
856 (cache->flow && !cache->flow->dead));
857 }
858
859 static void __cache_cleaner(struct tnl_vport *tnl_vport)
860 {
861 const struct tnl_mutable_config *mutable =
862 rcu_dereference(tnl_vport->mutable);
863 const struct tnl_cache *cache = rcu_dereference(tnl_vport->cache);
864
865 if (cache && !check_cache_valid(cache, mutable) &&
866 spin_trylock_bh(&tnl_vport->cache_lock)) {
867 assign_cache_rcu(tnl_vport_to_vport(tnl_vport), NULL);
868 spin_unlock_bh(&tnl_vport->cache_lock);
869 }
870 }
871
872 static void cache_cleaner(struct work_struct *work)
873 {
874 int i;
875
876 schedule_cache_cleaner();
877
878 rcu_read_lock();
879 for (i = 0; i < PORT_TABLE_SIZE; i++) {
880 struct hlist_node *n;
881 struct hlist_head *bucket;
882 struct tnl_vport *tnl_vport;
883
884 bucket = &port_table[i];
885 hlist_for_each_entry_rcu(tnl_vport, n, bucket, hash_node)
886 __cache_cleaner(tnl_vport);
887 }
888 rcu_read_unlock();
889 }
890
891 static void create_eth_hdr(struct tnl_cache *cache, struct hh_cache *hh)
892 {
893 void *cache_data = get_cached_header(cache);
894 int hh_off;
895
896 #ifdef HAVE_HH_SEQ
897 unsigned hh_seq;
898
899 do {
900 hh_seq = read_seqbegin(&hh->hh_lock);
901 hh_off = HH_DATA_ALIGN(hh->hh_len) - hh->hh_len;
902 memcpy(cache_data, (void *)hh->hh_data + hh_off, hh->hh_len);
903 cache->hh_len = hh->hh_len;
904 } while (read_seqretry(&hh->hh_lock, hh_seq));
905
906 cache->hh_seq = hh_seq;
907 #else
908 read_lock(&hh->hh_lock);
909 hh_off = HH_DATA_ALIGN(hh->hh_len) - hh->hh_len;
910 memcpy(cache_data, (void *)hh->hh_data + hh_off, hh->hh_len);
911 cache->hh_len = hh->hh_len;
912 read_unlock(&hh->hh_lock);
913 #endif
914 }
915
916 static struct tnl_cache *build_cache(struct vport *vport,
917 const struct tnl_mutable_config *mutable,
918 struct rtable *rt)
919 {
920 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
921 static const struct ovs_key_ipv4_tunnel tun_key;
922 struct tnl_cache *cache;
923 void *cache_data;
924 int cache_len;
925 struct hh_cache *hh;
926 int tunnel_hlen;
927
928 if (!(mutable->flags & TNL_F_HDR_CACHE))
929 return NULL;
930
931 tunnel_hlen = tnl_vport->tnl_ops->hdr_len(mutable, &tun_key);
932 if (tunnel_hlen < 0)
933 return NULL;
934
935 tunnel_hlen += sizeof(struct iphdr);
936
937 /*
938 * If there is no entry in the ARP cache or if this device does not
939 * support hard header caching just fall back to the IP stack.
940 */
941
942 hh = rt_hh(rt);
943 if (!hh)
944 return NULL;
945
946 /*
947 * If lock is contended fall back to directly building the header.
948 * We're not going to help performance by sitting here spinning.
949 */
950 if (!spin_trylock(&tnl_vport->cache_lock))
951 return NULL;
952
953 cache = cache_dereference(tnl_vport);
954 if (check_cache_valid(cache, mutable))
955 goto unlock;
956 else
957 cache = NULL;
958
959 cache_len = LL_RESERVED_SPACE(rt_dst(rt).dev) + tunnel_hlen;
960
961 cache = kzalloc(ALIGN(sizeof(struct tnl_cache), CACHE_DATA_ALIGN) +
962 cache_len, GFP_ATOMIC);
963 if (!cache)
964 goto unlock;
965
966 create_eth_hdr(cache, hh);
967 cache_data = get_cached_header(cache) + cache->hh_len;
968 cache->len = cache->hh_len + tunnel_hlen;
969
970 create_tunnel_header(vport, mutable, &tun_key, rt, cache_data);
971
972 cache->mutable_seq = mutable->seq;
973 cache->rt = rt;
974 #ifdef NEED_CACHE_TIMEOUT
975 cache->expiration = jiffies + tnl_vport->cache_exp_interval;
976 #endif
977
978 if (ovs_is_internal_dev(rt_dst(rt).dev)) {
979 struct sw_flow_key flow_key;
980 struct vport *dst_vport;
981 struct sk_buff *skb;
982 int err;
983 int flow_key_len;
984 struct sw_flow *flow;
985
986 dst_vport = ovs_internal_dev_get_vport(rt_dst(rt).dev);
987 if (!dst_vport)
988 goto done;
989
990 skb = alloc_skb(cache->len, GFP_ATOMIC);
991 if (!skb)
992 goto done;
993
994 __skb_put(skb, cache->len);
995 memcpy(skb->data, get_cached_header(cache), cache->len);
996
997 err = ovs_flow_extract(skb, dst_vport->port_no, &flow_key,
998 &flow_key_len);
999
1000 consume_skb(skb);
1001 if (err)
1002 goto done;
1003
1004 flow = ovs_flow_tbl_lookup(rcu_dereference(dst_vport->dp->table),
1005 &flow_key, flow_key_len);
1006 if (flow) {
1007 cache->flow = flow;
1008 ovs_flow_hold(flow);
1009 }
1010 }
1011
1012 done:
1013 assign_cache_rcu(vport, cache);
1014
1015 unlock:
1016 spin_unlock(&tnl_vport->cache_lock);
1017
1018 return cache;
1019 }
1020
1021 static struct rtable *__find_route(const struct tnl_mutable_config *mutable,
1022 __be32 saddr, __be32 daddr, u8 ipproto,
1023 u8 tos)
1024 {
1025 /* Tunnel configuration keeps DSCP part of TOS bits, But Linux
1026 * router expect RT_TOS bits only. */
1027
1028 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,39)
1029 struct flowi fl = { .nl_u = { .ip4_u = {
1030 .daddr = daddr,
1031 .saddr = saddr,
1032 .tos = RT_TOS(tos) } },
1033 .proto = ipproto };
1034 struct rtable *rt;
1035
1036 if (unlikely(ip_route_output_key(port_key_get_net(&mutable->key), &rt, &fl)))
1037 return ERR_PTR(-EADDRNOTAVAIL);
1038
1039 return rt;
1040 #else
1041 struct flowi4 fl = { .daddr = daddr,
1042 .saddr = saddr,
1043 .flowi4_tos = RT_TOS(tos),
1044 .flowi4_proto = ipproto };
1045
1046 return ip_route_output_key(port_key_get_net(&mutable->key), &fl);
1047 #endif
1048 }
1049
1050 static struct rtable *find_route(struct vport *vport,
1051 const struct tnl_mutable_config *mutable,
1052 __be32 saddr, __be32 daddr, u8 tos,
1053 struct tnl_cache **cache)
1054 {
1055 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
1056 struct tnl_cache *cur_cache = rcu_dereference(tnl_vport->cache);
1057
1058 *cache = NULL;
1059 tos = RT_TOS(tos);
1060
1061 if (tos == RT_TOS(mutable->tos) &&
1062 check_cache_valid(cur_cache, mutable)) {
1063 *cache = cur_cache;
1064 return cur_cache->rt;
1065 } else {
1066 struct rtable *rt;
1067
1068 rt = __find_route(mutable, saddr, daddr,
1069 tnl_vport->tnl_ops->ipproto, tos);
1070 if (IS_ERR(rt))
1071 return NULL;
1072 if (likely(tos == RT_TOS(mutable->tos)))
1073 *cache = build_cache(vport, mutable, rt);
1074
1075 return rt;
1076 }
1077 }
1078
1079 static bool need_linearize(const struct sk_buff *skb)
1080 {
1081 int i;
1082
1083 if (unlikely(skb_shinfo(skb)->frag_list))
1084 return true;
1085
1086 /*
1087 * Generally speaking we should linearize if there are paged frags.
1088 * However, if all of the refcounts are 1 we know nobody else can
1089 * change them from underneath us and we can skip the linearization.
1090 */
1091 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
1092 if (unlikely(page_count(skb_frag_page(&skb_shinfo(skb)->frags[i])) > 1))
1093 return true;
1094
1095 return false;
1096 }
1097
1098 static struct sk_buff *handle_offloads(struct sk_buff *skb,
1099 const struct tnl_mutable_config *mutable,
1100 const struct rtable *rt,
1101 int tunnel_hlen)
1102 {
1103 int min_headroom;
1104 int err;
1105
1106 min_headroom = LL_RESERVED_SPACE(rt_dst(rt).dev) + rt_dst(rt).header_len
1107 + tunnel_hlen
1108 + (vlan_tx_tag_present(skb) ? VLAN_HLEN : 0);
1109
1110 if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) {
1111 int head_delta = SKB_DATA_ALIGN(min_headroom -
1112 skb_headroom(skb) +
1113 16);
1114 err = pskb_expand_head(skb, max_t(int, head_delta, 0),
1115 0, GFP_ATOMIC);
1116 if (unlikely(err))
1117 goto error_free;
1118 }
1119
1120 forward_ip_summed(skb, true);
1121
1122 if (skb_is_gso(skb)) {
1123 struct sk_buff *nskb;
1124
1125 nskb = skb_gso_segment(skb, 0);
1126 if (IS_ERR(nskb)) {
1127 kfree_skb(skb);
1128 err = PTR_ERR(nskb);
1129 goto error;
1130 }
1131
1132 consume_skb(skb);
1133 skb = nskb;
1134 } else if (get_ip_summed(skb) == OVS_CSUM_PARTIAL) {
1135 /* Pages aren't locked and could change at any time.
1136 * If this happens after we compute the checksum, the
1137 * checksum will be wrong. We linearize now to avoid
1138 * this problem.
1139 */
1140 if (unlikely(need_linearize(skb))) {
1141 err = __skb_linearize(skb);
1142 if (unlikely(err))
1143 goto error_free;
1144 }
1145
1146 err = skb_checksum_help(skb);
1147 if (unlikely(err))
1148 goto error_free;
1149 }
1150
1151 set_ip_summed(skb, OVS_CSUM_NONE);
1152
1153 return skb;
1154
1155 error_free:
1156 kfree_skb(skb);
1157 error:
1158 return ERR_PTR(err);
1159 }
1160
1161 static int send_frags(struct sk_buff *skb,
1162 int tunnel_hlen)
1163 {
1164 int sent_len;
1165
1166 sent_len = 0;
1167 while (skb) {
1168 struct sk_buff *next = skb->next;
1169 int frag_len = skb->len - tunnel_hlen;
1170 int err;
1171
1172 skb->next = NULL;
1173 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
1174
1175 err = ip_local_out(skb);
1176 skb = next;
1177 if (unlikely(net_xmit_eval(err)))
1178 goto free_frags;
1179 sent_len += frag_len;
1180 }
1181
1182 return sent_len;
1183
1184 free_frags:
1185 /*
1186 * There's no point in continuing to send fragments once one has been
1187 * dropped so just free the rest. This may help improve the congestion
1188 * that caused the first packet to be dropped.
1189 */
1190 ovs_tnl_free_linked_skbs(skb);
1191 return sent_len;
1192 }
1193
1194 int ovs_tnl_send(struct vport *vport, struct sk_buff *skb)
1195 {
1196 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
1197 const struct tnl_mutable_config *mutable = rcu_dereference(tnl_vport->mutable);
1198 enum vport_err_type err = VPORT_E_TX_ERROR;
1199 struct rtable *rt;
1200 struct dst_entry *unattached_dst = NULL;
1201 struct tnl_cache *cache;
1202 struct ovs_key_ipv4_tunnel tun_key;
1203 int sent_len = 0;
1204 int tunnel_hlen;
1205 __be16 frag_off = 0;
1206 __be32 daddr;
1207 __be32 saddr;
1208 u8 ttl;
1209 u8 tos;
1210
1211 /* Validate the protocol headers before we try to use them. */
1212 if (skb->protocol == htons(ETH_P_8021Q) &&
1213 !vlan_tx_tag_present(skb)) {
1214 if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN)))
1215 goto error_free;
1216
1217 skb->protocol = vlan_eth_hdr(skb)->h_vlan_encapsulated_proto;
1218 skb_set_network_header(skb, VLAN_ETH_HLEN);
1219 }
1220
1221 if (skb->protocol == htons(ETH_P_IP)) {
1222 if (unlikely(!pskb_may_pull(skb, skb_network_offset(skb)
1223 + sizeof(struct iphdr))))
1224 skb->protocol = 0;
1225 }
1226 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1227 else if (skb->protocol == htons(ETH_P_IPV6)) {
1228 if (unlikely(!pskb_may_pull(skb, skb_network_offset(skb)
1229 + sizeof(struct ipv6hdr))))
1230 skb->protocol = 0;
1231 }
1232 #endif
1233
1234 /* If OVS_CB(skb)->tun_key is NULL, point it at the local tun_key here,
1235 * and zero it out.
1236 */
1237 if (!OVS_CB(skb)->tun_key) {
1238 memset(&tun_key, 0, sizeof(tun_key));
1239 OVS_CB(skb)->tun_key = &tun_key;
1240 }
1241
1242 tunnel_hlen = tnl_vport->tnl_ops->hdr_len(mutable, OVS_CB(skb)->tun_key);
1243 if (unlikely(tunnel_hlen < 0)) {
1244 err = VPORT_E_TX_DROPPED;
1245 goto error_free;
1246 }
1247 tunnel_hlen += sizeof(struct iphdr);
1248
1249 if (OVS_CB(skb)->tun_key->ipv4_dst) {
1250 daddr = OVS_CB(skb)->tun_key->ipv4_dst;
1251 saddr = OVS_CB(skb)->tun_key->ipv4_src;
1252 tos = OVS_CB(skb)->tun_key->ipv4_tos;
1253 ttl = OVS_CB(skb)->tun_key->ipv4_ttl;
1254 } else {
1255 u8 inner_tos;
1256 daddr = mutable->key.daddr;
1257 saddr = mutable->key.saddr;
1258
1259 if (unlikely(!daddr)) {
1260 /* Trying to sent packet from Null-port without
1261 * tunnel info? Drop this packet. */
1262 err = VPORT_E_TX_DROPPED;
1263 goto error_free;
1264 }
1265
1266 /* ToS */
1267 if (skb->protocol == htons(ETH_P_IP))
1268 inner_tos = ip_hdr(skb)->tos;
1269 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1270 else if (skb->protocol == htons(ETH_P_IPV6))
1271 inner_tos = ipv6_get_dsfield(ipv6_hdr(skb));
1272 #endif
1273 else
1274 inner_tos = 0;
1275
1276 if (mutable->flags & TNL_F_TOS_INHERIT)
1277 tos = inner_tos;
1278 else
1279 tos = mutable->tos;
1280
1281 tos = INET_ECN_encapsulate(tos, inner_tos);
1282
1283 /* TTL */
1284 ttl = mutable->ttl;
1285 if (mutable->flags & TNL_F_TTL_INHERIT) {
1286 if (skb->protocol == htons(ETH_P_IP))
1287 ttl = ip_hdr(skb)->ttl;
1288 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1289 else if (skb->protocol == htons(ETH_P_IPV6))
1290 ttl = ipv6_hdr(skb)->hop_limit;
1291 #endif
1292 }
1293
1294 }
1295
1296 /* Route lookup */
1297 rt = find_route(vport, mutable, saddr, daddr, tos, &cache);
1298 if (unlikely(!rt))
1299 goto error_free;
1300 if (unlikely(!cache))
1301 unattached_dst = &rt_dst(rt);
1302
1303 /* Reset SKB */
1304 nf_reset(skb);
1305 secpath_reset(skb);
1306 skb_dst_drop(skb);
1307 skb_clear_rxhash(skb);
1308
1309 /* Offloading */
1310 skb = handle_offloads(skb, mutable, rt, tunnel_hlen);
1311 if (IS_ERR(skb))
1312 goto error;
1313
1314 /* MTU */
1315 if (unlikely(!check_mtu(skb, vport, mutable, rt, &frag_off, tunnel_hlen))) {
1316 err = VPORT_E_TX_DROPPED;
1317 goto error_free;
1318 }
1319
1320 /*
1321 * If we are over the MTU, allow the IP stack to handle fragmentation.
1322 * Fragmentation is a slow path anyways.
1323 */
1324 if (unlikely(skb->len + tunnel_hlen > dst_mtu(&rt_dst(rt)) &&
1325 cache)) {
1326 unattached_dst = &rt_dst(rt);
1327 dst_hold(unattached_dst);
1328 cache = NULL;
1329 }
1330
1331 /* TTL Fixup. */
1332 if (!OVS_CB(skb)->tun_key->ipv4_dst) {
1333 if (!(mutable->flags & TNL_F_TTL_INHERIT)) {
1334 if (!ttl)
1335 ttl = ip4_dst_hoplimit(&rt_dst(rt));
1336 }
1337 }
1338
1339 while (skb) {
1340 struct iphdr *iph;
1341 struct sk_buff *next_skb = skb->next;
1342 skb->next = NULL;
1343
1344 if (unlikely(vlan_deaccel_tag(skb)))
1345 goto next;
1346
1347 if (likely(cache)) {
1348 skb_push(skb, cache->len);
1349 memcpy(skb->data, get_cached_header(cache), cache->len);
1350 skb_reset_mac_header(skb);
1351 skb_set_network_header(skb, cache->hh_len);
1352
1353 } else {
1354 skb_push(skb, tunnel_hlen);
1355 create_tunnel_header(vport, mutable, OVS_CB(skb)->tun_key, rt, skb->data);
1356 skb_reset_network_header(skb);
1357
1358 if (next_skb)
1359 skb_dst_set(skb, dst_clone(unattached_dst));
1360 else {
1361 skb_dst_set(skb, unattached_dst);
1362 unattached_dst = NULL;
1363 }
1364 }
1365 skb_set_transport_header(skb, skb_network_offset(skb) + sizeof(struct iphdr));
1366
1367 iph = ip_hdr(skb);
1368 iph->tos = tos;
1369 iph->ttl = ttl;
1370 iph->frag_off = frag_off;
1371 ip_select_ident(iph, &rt_dst(rt), NULL);
1372
1373 skb = tnl_vport->tnl_ops->update_header(vport, mutable,
1374 &rt_dst(rt), skb, tunnel_hlen);
1375 if (unlikely(!skb))
1376 goto next;
1377
1378 if (likely(cache)) {
1379 int orig_len = skb->len - cache->len;
1380 struct vport *cache_vport;
1381
1382 cache_vport = ovs_internal_dev_get_vport(rt_dst(rt).dev);
1383 skb->protocol = htons(ETH_P_IP);
1384 iph = ip_hdr(skb);
1385 iph->tot_len = htons(skb->len - skb_network_offset(skb));
1386 ip_send_check(iph);
1387
1388 if (cache_vport) {
1389 if (unlikely(compute_ip_summed(skb, true))) {
1390 kfree_skb(skb);
1391 goto next;
1392 }
1393
1394 OVS_CB(skb)->flow = cache->flow;
1395 ovs_vport_receive(cache_vport, skb);
1396 sent_len += orig_len;
1397 } else {
1398 int xmit_err;
1399
1400 skb->dev = rt_dst(rt).dev;
1401 xmit_err = dev_queue_xmit(skb);
1402
1403 if (likely(net_xmit_eval(xmit_err) == 0))
1404 sent_len += orig_len;
1405 }
1406 } else
1407 sent_len += send_frags(skb, tunnel_hlen);
1408
1409 next:
1410 skb = next_skb;
1411 }
1412
1413 if (unlikely(sent_len == 0))
1414 ovs_vport_record_error(vport, VPORT_E_TX_DROPPED);
1415
1416 goto out;
1417
1418 error_free:
1419 ovs_tnl_free_linked_skbs(skb);
1420 error:
1421 ovs_vport_record_error(vport, err);
1422 out:
1423 dst_release(unattached_dst);
1424 return sent_len;
1425 }
1426
1427 static const struct nla_policy tnl_policy[OVS_TUNNEL_ATTR_MAX + 1] = {
1428 [OVS_TUNNEL_ATTR_FLAGS] = { .type = NLA_U32 },
1429 [OVS_TUNNEL_ATTR_DST_IPV4] = { .type = NLA_U32 },
1430 [OVS_TUNNEL_ATTR_SRC_IPV4] = { .type = NLA_U32 },
1431 [OVS_TUNNEL_ATTR_OUT_KEY] = { .type = NLA_U64 },
1432 [OVS_TUNNEL_ATTR_IN_KEY] = { .type = NLA_U64 },
1433 [OVS_TUNNEL_ATTR_TOS] = { .type = NLA_U8 },
1434 [OVS_TUNNEL_ATTR_TTL] = { .type = NLA_U8 },
1435 };
1436
1437 /* Sets OVS_TUNNEL_ATTR_* fields in 'mutable', which must initially be
1438 * zeroed. */
1439 static int tnl_set_config(struct net *net, struct nlattr *options,
1440 const struct tnl_ops *tnl_ops,
1441 const struct vport *cur_vport,
1442 struct tnl_mutable_config *mutable)
1443 {
1444 const struct vport *old_vport;
1445 const struct tnl_mutable_config *old_mutable;
1446 struct nlattr *a[OVS_TUNNEL_ATTR_MAX + 1];
1447 int err;
1448
1449 port_key_set_net(&mutable->key, net);
1450 mutable->key.tunnel_type = tnl_ops->tunnel_type;
1451 if (!options)
1452 goto out;
1453
1454 err = nla_parse_nested(a, OVS_TUNNEL_ATTR_MAX, options, tnl_policy);
1455 if (err)
1456 return err;
1457
1458 if (!a[OVS_TUNNEL_ATTR_FLAGS] || !a[OVS_TUNNEL_ATTR_DST_IPV4])
1459 return -EINVAL;
1460
1461 mutable->flags = nla_get_u32(a[OVS_TUNNEL_ATTR_FLAGS]) & TNL_F_PUBLIC;
1462 mutable->key.daddr = nla_get_be32(a[OVS_TUNNEL_ATTR_DST_IPV4]);
1463
1464 if (a[OVS_TUNNEL_ATTR_SRC_IPV4]) {
1465 if (ipv4_is_multicast(mutable->key.daddr))
1466 return -EINVAL;
1467 mutable->key.saddr = nla_get_be32(a[OVS_TUNNEL_ATTR_SRC_IPV4]);
1468 }
1469
1470 if (a[OVS_TUNNEL_ATTR_TOS]) {
1471 mutable->tos = nla_get_u8(a[OVS_TUNNEL_ATTR_TOS]);
1472 /* Reject ToS config with ECN bits set. */
1473 if (mutable->tos & INET_ECN_MASK)
1474 return -EINVAL;
1475 }
1476
1477 if (a[OVS_TUNNEL_ATTR_TTL])
1478 mutable->ttl = nla_get_u8(a[OVS_TUNNEL_ATTR_TTL]);
1479
1480 if (!a[OVS_TUNNEL_ATTR_IN_KEY]) {
1481 mutable->key.tunnel_type |= TNL_T_KEY_MATCH;
1482 mutable->flags |= TNL_F_IN_KEY_MATCH;
1483 } else {
1484 mutable->key.tunnel_type |= TNL_T_KEY_EXACT;
1485 mutable->key.in_key = nla_get_be64(a[OVS_TUNNEL_ATTR_IN_KEY]);
1486 }
1487
1488 if (!a[OVS_TUNNEL_ATTR_OUT_KEY])
1489 mutable->flags |= TNL_F_OUT_KEY_ACTION;
1490 else
1491 mutable->out_key = nla_get_be64(a[OVS_TUNNEL_ATTR_OUT_KEY]);
1492
1493 mutable->mlink = 0;
1494 if (ipv4_is_multicast(mutable->key.daddr)) {
1495 struct net_device *dev;
1496 struct rtable *rt;
1497
1498 rt = __find_route(mutable, mutable->key.saddr, mutable->key.daddr,
1499 tnl_ops->ipproto, mutable->tos);
1500 if (IS_ERR(rt))
1501 return -EADDRNOTAVAIL;
1502 dev = rt_dst(rt).dev;
1503 ip_rt_put(rt);
1504 if (__in_dev_get_rtnl(dev) == NULL)
1505 return -EADDRNOTAVAIL;
1506 mutable->mlink = dev->ifindex;
1507 ip_mc_inc_group(__in_dev_get_rtnl(dev), mutable->key.daddr);
1508 }
1509
1510 out:
1511 old_vport = port_table_lookup(&mutable->key, &old_mutable);
1512 if (old_vport && old_vport != cur_vport)
1513 return -EEXIST;
1514
1515 return 0;
1516 }
1517
1518 struct vport *ovs_tnl_create(const struct vport_parms *parms,
1519 const struct vport_ops *vport_ops,
1520 const struct tnl_ops *tnl_ops)
1521 {
1522 struct vport *vport;
1523 struct tnl_vport *tnl_vport;
1524 struct tnl_mutable_config *mutable;
1525 int initial_frag_id;
1526 int err;
1527
1528 vport = ovs_vport_alloc(sizeof(struct tnl_vport), vport_ops, parms);
1529 if (IS_ERR(vport)) {
1530 err = PTR_ERR(vport);
1531 goto error;
1532 }
1533
1534 tnl_vport = tnl_vport_priv(vport);
1535
1536 strcpy(tnl_vport->name, parms->name);
1537 tnl_vport->tnl_ops = tnl_ops;
1538
1539 mutable = kzalloc(sizeof(struct tnl_mutable_config), GFP_KERNEL);
1540 if (!mutable) {
1541 err = -ENOMEM;
1542 goto error_free_vport;
1543 }
1544
1545 random_ether_addr(mutable->eth_addr);
1546
1547 get_random_bytes(&initial_frag_id, sizeof(int));
1548 atomic_set(&tnl_vport->frag_id, initial_frag_id);
1549
1550 err = tnl_set_config(ovs_dp_get_net(parms->dp), parms->options, tnl_ops,
1551 NULL, mutable);
1552 if (err)
1553 goto error_free_mutable;
1554
1555 spin_lock_init(&tnl_vport->cache_lock);
1556
1557 #ifdef NEED_CACHE_TIMEOUT
1558 tnl_vport->cache_exp_interval = MAX_CACHE_EXP -
1559 (net_random() % (MAX_CACHE_EXP / 2));
1560 #endif
1561
1562 rcu_assign_pointer(tnl_vport->mutable, mutable);
1563
1564 port_table_add_port(vport);
1565 return vport;
1566
1567 error_free_mutable:
1568 free_mutable_rtnl(mutable);
1569 kfree(mutable);
1570 error_free_vport:
1571 ovs_vport_free(vport);
1572 error:
1573 return ERR_PTR(err);
1574 }
1575
1576 int ovs_tnl_set_options(struct vport *vport, struct nlattr *options)
1577 {
1578 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
1579 const struct tnl_mutable_config *old_mutable;
1580 struct tnl_mutable_config *mutable;
1581 int err;
1582
1583 old_mutable = rtnl_dereference(tnl_vport->mutable);
1584 if (!old_mutable->key.daddr)
1585 return -EINVAL;
1586
1587 mutable = kzalloc(sizeof(struct tnl_mutable_config), GFP_KERNEL);
1588 if (!mutable) {
1589 err = -ENOMEM;
1590 goto error;
1591 }
1592
1593 /* Copy fields whose values should be retained. */
1594 mutable->seq = old_mutable->seq + 1;
1595 memcpy(mutable->eth_addr, old_mutable->eth_addr, ETH_ALEN);
1596
1597 /* Parse the others configured by userspace. */
1598 err = tnl_set_config(ovs_dp_get_net(vport->dp), options, tnl_vport->tnl_ops,
1599 vport, mutable);
1600 if (err)
1601 goto error_free;
1602
1603 if (port_hash(&mutable->key) != port_hash(&old_mutable->key))
1604 port_table_move_port(vport, mutable);
1605 else
1606 assign_config_rcu(vport, mutable);
1607
1608 return 0;
1609
1610 error_free:
1611 free_mutable_rtnl(mutable);
1612 kfree(mutable);
1613 error:
1614 return err;
1615 }
1616
1617 int ovs_tnl_get_options(const struct vport *vport, struct sk_buff *skb)
1618 {
1619 const struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
1620 const struct tnl_mutable_config *mutable = rcu_dereference_rtnl(tnl_vport->mutable);
1621
1622 if (nla_put_u32(skb, OVS_TUNNEL_ATTR_FLAGS,
1623 mutable->flags & TNL_F_PUBLIC) ||
1624 nla_put_be32(skb, OVS_TUNNEL_ATTR_DST_IPV4, mutable->key.daddr))
1625 goto nla_put_failure;
1626
1627 if (!(mutable->flags & TNL_F_IN_KEY_MATCH) &&
1628 nla_put_be64(skb, OVS_TUNNEL_ATTR_IN_KEY, mutable->key.in_key))
1629 goto nla_put_failure;
1630 if (!(mutable->flags & TNL_F_OUT_KEY_ACTION) &&
1631 nla_put_be64(skb, OVS_TUNNEL_ATTR_OUT_KEY, mutable->out_key))
1632 goto nla_put_failure;
1633 if (mutable->key.saddr &&
1634 nla_put_be32(skb, OVS_TUNNEL_ATTR_SRC_IPV4, mutable->key.saddr))
1635 goto nla_put_failure;
1636 if (mutable->tos && nla_put_u8(skb, OVS_TUNNEL_ATTR_TOS, mutable->tos))
1637 goto nla_put_failure;
1638 if (mutable->ttl && nla_put_u8(skb, OVS_TUNNEL_ATTR_TTL, mutable->ttl))
1639 goto nla_put_failure;
1640
1641 return 0;
1642
1643 nla_put_failure:
1644 return -EMSGSIZE;
1645 }
1646
1647 static void free_port_rcu(struct rcu_head *rcu)
1648 {
1649 struct tnl_vport *tnl_vport = container_of(rcu,
1650 struct tnl_vport, rcu);
1651
1652 free_cache((struct tnl_cache __force *)tnl_vport->cache);
1653 kfree((struct tnl_mutable __force *)tnl_vport->mutable);
1654 ovs_vport_free(tnl_vport_to_vport(tnl_vport));
1655 }
1656
1657 void ovs_tnl_destroy(struct vport *vport)
1658 {
1659 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
1660 struct tnl_mutable_config *mutable;
1661
1662 mutable = rtnl_dereference(tnl_vport->mutable);
1663 port_table_remove_port(vport);
1664 free_mutable_rtnl(mutable);
1665 call_rcu(&tnl_vport->rcu, free_port_rcu);
1666 }
1667
1668 int ovs_tnl_set_addr(struct vport *vport, const unsigned char *addr)
1669 {
1670 struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
1671 struct tnl_mutable_config *old_mutable, *mutable;
1672
1673 old_mutable = rtnl_dereference(tnl_vport->mutable);
1674 mutable = kmemdup(old_mutable, sizeof(struct tnl_mutable_config), GFP_KERNEL);
1675 if (!mutable)
1676 return -ENOMEM;
1677
1678 old_mutable->mlink = 0;
1679
1680 memcpy(mutable->eth_addr, addr, ETH_ALEN);
1681 assign_config_rcu(vport, mutable);
1682
1683 return 0;
1684 }
1685
1686 const char *ovs_tnl_get_name(const struct vport *vport)
1687 {
1688 const struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
1689 return tnl_vport->name;
1690 }
1691
1692 const unsigned char *ovs_tnl_get_addr(const struct vport *vport)
1693 {
1694 const struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
1695 return rcu_dereference_rtnl(tnl_vport->mutable)->eth_addr;
1696 }
1697
1698 void ovs_tnl_free_linked_skbs(struct sk_buff *skb)
1699 {
1700 while (skb) {
1701 struct sk_buff *next = skb->next;
1702 kfree_skb(skb);
1703 skb = next;
1704 }
1705 }
1706
1707 int ovs_tnl_init(void)
1708 {
1709 int i;
1710
1711 port_table = kmalloc(PORT_TABLE_SIZE * sizeof(struct hlist_head *),
1712 GFP_KERNEL);
1713 if (!port_table)
1714 return -ENOMEM;
1715
1716 for (i = 0; i < PORT_TABLE_SIZE; i++)
1717 INIT_HLIST_HEAD(&port_table[i]);
1718
1719 return 0;
1720 }
1721
1722 void ovs_tnl_exit(void)
1723 {
1724 kfree(port_table);
1725 }
openvswitch packages for PVE