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ARC: support HIGHMEM even without PAE40
[linux/fpc-iii.git] / net / openvswitch / actions.c
blobe9dd47b2a85b9e7b65795335b5722e89ac5c3ed8
1 /*
2 * Copyright (c) 2007-2014 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/skbuff.h>
22 #include <linux/in.h>
23 #include <linux/ip.h>
24 #include <linux/openvswitch.h>
25 #include <linux/netfilter_ipv6.h>
26 #include <linux/sctp.h>
27 #include <linux/tcp.h>
28 #include <linux/udp.h>
29 #include <linux/in6.h>
30 #include <linux/if_arp.h>
31 #include <linux/if_vlan.h>
32
33 #include <net/dst.h>
34 #include <net/ip.h>
35 #include <net/ipv6.h>
36 #include <net/ip6_fib.h>
37 #include <net/checksum.h>
38 #include <net/dsfield.h>
39 #include <net/mpls.h>
40 #include <net/sctp/checksum.h>
41
42 #include "datapath.h"
43 #include "flow.h"
44 #include "conntrack.h"
45 #include "vport.h"
46
47 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
48 struct sw_flow_key *key,
49 const struct nlattr *attr, int len);
50
51 struct deferred_action {
52 struct sk_buff *skb;
53 const struct nlattr *actions;
54
55 /* Store pkt_key clone when creating deferred action. */
56 struct sw_flow_key pkt_key;
57 };
58
59 #define MAX_L2_LEN (VLAN_ETH_HLEN + 3 * MPLS_HLEN)
60 struct ovs_frag_data {
61 unsigned long dst;
62 struct vport *vport;
63 struct ovs_skb_cb cb;
64 __be16 inner_protocol;
65 __u16 vlan_tci;
66 __be16 vlan_proto;
67 unsigned int l2_len;
68 u8 l2_data[MAX_L2_LEN];
69 };
70
71 static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);
72
73 #define DEFERRED_ACTION_FIFO_SIZE 10
74 struct action_fifo {
75 int head;
76 int tail;
77 /* Deferred action fifo queue storage. */
78 struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
79 };
80
81 static struct action_fifo __percpu *action_fifos;
82 static DEFINE_PER_CPU(int, exec_actions_level);
83
84 static void action_fifo_init(struct action_fifo *fifo)
85 {
86 fifo->head = 0;
87 fifo->tail = 0;
88 }
89
90 static bool action_fifo_is_empty(const struct action_fifo *fifo)
91 {
92 return (fifo->head == fifo->tail);
93 }
94
95 static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
96 {
97 if (action_fifo_is_empty(fifo))
98 return NULL;
99
100 return &fifo->fifo[fifo->tail++];
101 }
102
103 static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
104 {
105 if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
106 return NULL;
107
108 return &fifo->fifo[fifo->head++];
109 }
110
111 /* Return true if fifo is not full */
112 static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
113 const struct sw_flow_key *key,
114 const struct nlattr *attr)
115 {
116 struct action_fifo *fifo;
117 struct deferred_action *da;
118
119 fifo = this_cpu_ptr(action_fifos);
120 da = action_fifo_put(fifo);
121 if (da) {
122 da->skb = skb;
123 da->actions = attr;
124 da->pkt_key = *key;
125 }
126
127 return da;
128 }
129
130 static void invalidate_flow_key(struct sw_flow_key *key)
131 {
132 key->eth.type = htons(0);
133 }
134
135 static bool is_flow_key_valid(const struct sw_flow_key *key)
136 {
137 return !!key->eth.type;
138 }
139
140 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
141 const struct ovs_action_push_mpls *mpls)
142 {
143 __be32 *new_mpls_lse;
144 struct ethhdr *hdr;
145
146 /* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */
147 if (skb->encapsulation)
148 return -ENOTSUPP;
149
150 if (skb_cow_head(skb, MPLS_HLEN) < 0)
151 return -ENOMEM;
152
153 skb_push(skb, MPLS_HLEN);
154 memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb),
155 skb->mac_len);
156 skb_reset_mac_header(skb);
157
158 new_mpls_lse = (__be32 *)skb_mpls_header(skb);
159 *new_mpls_lse = mpls->mpls_lse;
160
161 skb_postpush_rcsum(skb, new_mpls_lse, MPLS_HLEN);
162
163 hdr = eth_hdr(skb);
164 hdr->h_proto = mpls->mpls_ethertype;
165
166 if (!skb->inner_protocol)
167 skb_set_inner_protocol(skb, skb->protocol);
168 skb->protocol = mpls->mpls_ethertype;
169
170 invalidate_flow_key(key);
171 return 0;
172 }
173
174 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
175 const __be16 ethertype)
176 {
177 struct ethhdr *hdr;
178 int err;
179
180 err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
181 if (unlikely(err))
182 return err;
183
184 skb_postpull_rcsum(skb, skb_mpls_header(skb), MPLS_HLEN);
185
186 memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb),
187 skb->mac_len);
188
189 __skb_pull(skb, MPLS_HLEN);
190 skb_reset_mac_header(skb);
191
192 /* skb_mpls_header() is used to locate the ethertype
193 * field correctly in the presence of VLAN tags.
194 */
195 hdr = (struct ethhdr *)(skb_mpls_header(skb) - ETH_HLEN);
196 hdr->h_proto = ethertype;
197 if (eth_p_mpls(skb->protocol))
198 skb->protocol = ethertype;
199
200 invalidate_flow_key(key);
201 return 0;
202 }
203
204 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
205 const __be32 *mpls_lse, const __be32 *mask)
206 {
207 __be32 *stack;
208 __be32 lse;
209 int err;
210
211 err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
212 if (unlikely(err))
213 return err;
214
215 stack = (__be32 *)skb_mpls_header(skb);
216 lse = OVS_MASKED(*stack, *mpls_lse, *mask);
217 if (skb->ip_summed == CHECKSUM_COMPLETE) {
218 __be32 diff[] = { ~(*stack), lse };
219
220 skb->csum = ~csum_partial((char *)diff, sizeof(diff),
221 ~skb->csum);
222 }
223
224 *stack = lse;
225 flow_key->mpls.top_lse = lse;
226 return 0;
227 }
228
229 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
230 {
231 int err;
232
233 err = skb_vlan_pop(skb);
234 if (skb_vlan_tag_present(skb))
235 invalidate_flow_key(key);
236 else
237 key->eth.tci = 0;
238 return err;
239 }
240
241 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
242 const struct ovs_action_push_vlan *vlan)
243 {
244 if (skb_vlan_tag_present(skb))
245 invalidate_flow_key(key);
246 else
247 key->eth.tci = vlan->vlan_tci;
248 return skb_vlan_push(skb, vlan->vlan_tpid,
249 ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
250 }
251
252 /* 'src' is already properly masked. */
253 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
254 {
255 u16 *dst = (u16 *)dst_;
256 const u16 *src = (const u16 *)src_;
257 const u16 *mask = (const u16 *)mask_;
258
259 OVS_SET_MASKED(dst[0], src[0], mask[0]);
260 OVS_SET_MASKED(dst[1], src[1], mask[1]);
261 OVS_SET_MASKED(dst[2], src[2], mask[2]);
262 }
263
264 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
265 const struct ovs_key_ethernet *key,
266 const struct ovs_key_ethernet *mask)
267 {
268 int err;
269
270 err = skb_ensure_writable(skb, ETH_HLEN);
271 if (unlikely(err))
272 return err;
273
274 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
275
276 ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
277 mask->eth_src);
278 ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
279 mask->eth_dst);
280
281 skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
282
283 ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
284 ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
285 return 0;
286 }
287
288 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
289 __be32 addr, __be32 new_addr)
290 {
291 int transport_len = skb->len - skb_transport_offset(skb);
292
293 if (nh->frag_off & htons(IP_OFFSET))
294 return;
295
296 if (nh->protocol == IPPROTO_TCP) {
297 if (likely(transport_len >= sizeof(struct tcphdr)))
298 inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
299 addr, new_addr, true);
300 } else if (nh->protocol == IPPROTO_UDP) {
301 if (likely(transport_len >= sizeof(struct udphdr))) {
302 struct udphdr *uh = udp_hdr(skb);
303
304 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
305 inet_proto_csum_replace4(&uh->check, skb,
306 addr, new_addr, true);
307 if (!uh->check)
308 uh->check = CSUM_MANGLED_0;
309 }
310 }
311 }
312 }
313
314 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
315 __be32 *addr, __be32 new_addr)
316 {
317 update_ip_l4_checksum(skb, nh, *addr, new_addr);
318 csum_replace4(&nh->check, *addr, new_addr);
319 skb_clear_hash(skb);
320 *addr = new_addr;
321 }
322
323 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
324 __be32 addr[4], const __be32 new_addr[4])
325 {
326 int transport_len = skb->len - skb_transport_offset(skb);
327
328 if (l4_proto == NEXTHDR_TCP) {
329 if (likely(transport_len >= sizeof(struct tcphdr)))
330 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
331 addr, new_addr, true);
332 } else if (l4_proto == NEXTHDR_UDP) {
333 if (likely(transport_len >= sizeof(struct udphdr))) {
334 struct udphdr *uh = udp_hdr(skb);
335
336 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
337 inet_proto_csum_replace16(&uh->check, skb,
338 addr, new_addr, true);
339 if (!uh->check)
340 uh->check = CSUM_MANGLED_0;
341 }
342 }
343 } else if (l4_proto == NEXTHDR_ICMP) {
344 if (likely(transport_len >= sizeof(struct icmp6hdr)))
345 inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
346 skb, addr, new_addr, true);
347 }
348 }
349
350 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
351 const __be32 mask[4], __be32 masked[4])
352 {
353 masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
354 masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
355 masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
356 masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
357 }
358
359 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
360 __be32 addr[4], const __be32 new_addr[4],
361 bool recalculate_csum)
362 {
363 if (recalculate_csum)
364 update_ipv6_checksum(skb, l4_proto, addr, new_addr);
365
366 skb_clear_hash(skb);
367 memcpy(addr, new_addr, sizeof(__be32[4]));
368 }
369
370 static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask)
371 {
372 /* Bits 21-24 are always unmasked, so this retains their values. */
373 OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16));
374 OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8));
375 OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask);
376 }
377
378 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
379 u8 mask)
380 {
381 new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);
382
383 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
384 nh->ttl = new_ttl;
385 }
386
387 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
388 const struct ovs_key_ipv4 *key,
389 const struct ovs_key_ipv4 *mask)
390 {
391 struct iphdr *nh;
392 __be32 new_addr;
393 int err;
394
395 err = skb_ensure_writable(skb, skb_network_offset(skb) +
396 sizeof(struct iphdr));
397 if (unlikely(err))
398 return err;
399
400 nh = ip_hdr(skb);
401
402 /* Setting an IP addresses is typically only a side effect of
403 * matching on them in the current userspace implementation, so it
404 * makes sense to check if the value actually changed.
405 */
406 if (mask->ipv4_src) {
407 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
408
409 if (unlikely(new_addr != nh->saddr)) {
410 set_ip_addr(skb, nh, &nh->saddr, new_addr);
411 flow_key->ipv4.addr.src = new_addr;
412 }
413 }
414 if (mask->ipv4_dst) {
415 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
416
417 if (unlikely(new_addr != nh->daddr)) {
418 set_ip_addr(skb, nh, &nh->daddr, new_addr);
419 flow_key->ipv4.addr.dst = new_addr;
420 }
421 }
422 if (mask->ipv4_tos) {
423 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
424 flow_key->ip.tos = nh->tos;
425 }
426 if (mask->ipv4_ttl) {
427 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
428 flow_key->ip.ttl = nh->ttl;
429 }
430
431 return 0;
432 }
433
434 static bool is_ipv6_mask_nonzero(const __be32 addr[4])
435 {
436 return !!(addr[0] | addr[1] | addr[2] | addr[3]);
437 }
438
439 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
440 const struct ovs_key_ipv6 *key,
441 const struct ovs_key_ipv6 *mask)
442 {
443 struct ipv6hdr *nh;
444 int err;
445
446 err = skb_ensure_writable(skb, skb_network_offset(skb) +
447 sizeof(struct ipv6hdr));
448 if (unlikely(err))
449 return err;
450
451 nh = ipv6_hdr(skb);
452
453 /* Setting an IP addresses is typically only a side effect of
454 * matching on them in the current userspace implementation, so it
455 * makes sense to check if the value actually changed.
456 */
457 if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
458 __be32 *saddr = (__be32 *)&nh->saddr;
459 __be32 masked[4];
460
461 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
462
463 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
464 set_ipv6_addr(skb, key->ipv6_proto, saddr, masked,
465 true);
466 memcpy(&flow_key->ipv6.addr.src, masked,
467 sizeof(flow_key->ipv6.addr.src));
468 }
469 }
470 if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
471 unsigned int offset = 0;
472 int flags = IP6_FH_F_SKIP_RH;
473 bool recalc_csum = true;
474 __be32 *daddr = (__be32 *)&nh->daddr;
475 __be32 masked[4];
476
477 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
478
479 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
480 if (ipv6_ext_hdr(nh->nexthdr))
481 recalc_csum = (ipv6_find_hdr(skb, &offset,
482 NEXTHDR_ROUTING,
483 NULL, &flags)
484 != NEXTHDR_ROUTING);
485
486 set_ipv6_addr(skb, key->ipv6_proto, daddr, masked,
487 recalc_csum);
488 memcpy(&flow_key->ipv6.addr.dst, masked,
489 sizeof(flow_key->ipv6.addr.dst));
490 }
491 }
492 if (mask->ipv6_tclass) {
493 ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass);
494 flow_key->ip.tos = ipv6_get_dsfield(nh);
495 }
496 if (mask->ipv6_label) {
497 set_ipv6_fl(nh, ntohl(key->ipv6_label),
498 ntohl(mask->ipv6_label));
499 flow_key->ipv6.label =
500 *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
501 }
502 if (mask->ipv6_hlimit) {
503 OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit,
504 mask->ipv6_hlimit);
505 flow_key->ip.ttl = nh->hop_limit;
506 }
507 return 0;
508 }
509
510 /* Must follow skb_ensure_writable() since that can move the skb data. */
511 static void set_tp_port(struct sk_buff *skb, __be16 *port,
512 __be16 new_port, __sum16 *check)
513 {
514 inet_proto_csum_replace2(check, skb, *port, new_port, false);
515 *port = new_port;
516 }
517
518 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
519 const struct ovs_key_udp *key,
520 const struct ovs_key_udp *mask)
521 {
522 struct udphdr *uh;
523 __be16 src, dst;
524 int err;
525
526 err = skb_ensure_writable(skb, skb_transport_offset(skb) +
527 sizeof(struct udphdr));
528 if (unlikely(err))
529 return err;
530
531 uh = udp_hdr(skb);
532 /* Either of the masks is non-zero, so do not bother checking them. */
533 src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
534 dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);
535
536 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
537 if (likely(src != uh->source)) {
538 set_tp_port(skb, &uh->source, src, &uh->check);
539 flow_key->tp.src = src;
540 }
541 if (likely(dst != uh->dest)) {
542 set_tp_port(skb, &uh->dest, dst, &uh->check);
543 flow_key->tp.dst = dst;
544 }
545
546 if (unlikely(!uh->check))
547 uh->check = CSUM_MANGLED_0;
548 } else {
549 uh->source = src;
550 uh->dest = dst;
551 flow_key->tp.src = src;
552 flow_key->tp.dst = dst;
553 }
554
555 skb_clear_hash(skb);
556
557 return 0;
558 }
559
560 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
561 const struct ovs_key_tcp *key,
562 const struct ovs_key_tcp *mask)
563 {
564 struct tcphdr *th;
565 __be16 src, dst;
566 int err;
567
568 err = skb_ensure_writable(skb, skb_transport_offset(skb) +
569 sizeof(struct tcphdr));
570 if (unlikely(err))
571 return err;
572
573 th = tcp_hdr(skb);
574 src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
575 if (likely(src != th->source)) {
576 set_tp_port(skb, &th->source, src, &th->check);
577 flow_key->tp.src = src;
578 }
579 dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
580 if (likely(dst != th->dest)) {
581 set_tp_port(skb, &th->dest, dst, &th->check);
582 flow_key->tp.dst = dst;
583 }
584 skb_clear_hash(skb);
585
586 return 0;
587 }
588
589 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
590 const struct ovs_key_sctp *key,
591 const struct ovs_key_sctp *mask)
592 {
593 unsigned int sctphoff = skb_transport_offset(skb);
594 struct sctphdr *sh;
595 __le32 old_correct_csum, new_csum, old_csum;
596 int err;
597
598 err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
599 if (unlikely(err))
600 return err;
601
602 sh = sctp_hdr(skb);
603 old_csum = sh->checksum;
604 old_correct_csum = sctp_compute_cksum(skb, sctphoff);
605
606 sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
607 sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
608
609 new_csum = sctp_compute_cksum(skb, sctphoff);
610
611 /* Carry any checksum errors through. */
612 sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
613
614 skb_clear_hash(skb);
615 flow_key->tp.src = sh->source;
616 flow_key->tp.dst = sh->dest;
617
618 return 0;
619 }
620
621 static int ovs_vport_output(struct net *net, struct sock *sk, struct sk_buff *skb)
622 {
623 struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
624 struct vport *vport = data->vport;
625
626 if (skb_cow_head(skb, data->l2_len) < 0) {
627 kfree_skb(skb);
628 return -ENOMEM;
629 }
630
631 __skb_dst_copy(skb, data->dst);
632 *OVS_CB(skb) = data->cb;
633 skb->inner_protocol = data->inner_protocol;
634 skb->vlan_tci = data->vlan_tci;
635 skb->vlan_proto = data->vlan_proto;
636
637 /* Reconstruct the MAC header. */
638 skb_push(skb, data->l2_len);
639 memcpy(skb->data, &data->l2_data, data->l2_len);
640 skb_postpush_rcsum(skb, skb->data, data->l2_len);
641 skb_reset_mac_header(skb);
642
643 ovs_vport_send(vport, skb);
644 return 0;
645 }
646
647 static unsigned int
648 ovs_dst_get_mtu(const struct dst_entry *dst)
649 {
650 return dst->dev->mtu;
651 }
652
653 static struct dst_ops ovs_dst_ops = {
654 .family = AF_UNSPEC,
655 .mtu = ovs_dst_get_mtu,
656 };
657
658 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
659 * ovs_vport_output(), which is called once per fragmented packet.
660 */
661 static void prepare_frag(struct vport *vport, struct sk_buff *skb)
662 {
663 unsigned int hlen = skb_network_offset(skb);
664 struct ovs_frag_data *data;
665
666 data = this_cpu_ptr(&ovs_frag_data_storage);
667 data->dst = skb->_skb_refdst;
668 data->vport = vport;
669 data->cb = *OVS_CB(skb);
670 data->inner_protocol = skb->inner_protocol;
671 data->vlan_tci = skb->vlan_tci;
672 data->vlan_proto = skb->vlan_proto;
673 data->l2_len = hlen;
674 memcpy(&data->l2_data, skb->data, hlen);
675
676 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
677 skb_pull(skb, hlen);
678 }
679
680 static void ovs_fragment(struct net *net, struct vport *vport,
681 struct sk_buff *skb, u16 mru, __be16 ethertype)
682 {
683 if (skb_network_offset(skb) > MAX_L2_LEN) {
684 OVS_NLERR(1, "L2 header too long to fragment");
685 goto err;
686 }
687
688 if (ethertype == htons(ETH_P_IP)) {
689 struct dst_entry ovs_dst;
690 unsigned long orig_dst;
691
692 prepare_frag(vport, skb);
693 dst_init(&ovs_dst, &ovs_dst_ops, NULL, 1,
694 DST_OBSOLETE_NONE, DST_NOCOUNT);
695 ovs_dst.dev = vport->dev;
696
697 orig_dst = skb->_skb_refdst;
698 skb_dst_set_noref(skb, &ovs_dst);
699 IPCB(skb)->frag_max_size = mru;
700
701 ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
702 refdst_drop(orig_dst);
703 } else if (ethertype == htons(ETH_P_IPV6)) {
704 const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
705 unsigned long orig_dst;
706 struct rt6_info ovs_rt;
707
708 if (!v6ops) {
709 goto err;
710 }
711
712 prepare_frag(vport, skb);
713 memset(&ovs_rt, 0, sizeof(ovs_rt));
714 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
715 DST_OBSOLETE_NONE, DST_NOCOUNT);
716 ovs_rt.dst.dev = vport->dev;
717
718 orig_dst = skb->_skb_refdst;
719 skb_dst_set_noref(skb, &ovs_rt.dst);
720 IP6CB(skb)->frag_max_size = mru;
721
722 v6ops->fragment(net, skb->sk, skb, ovs_vport_output);
723 refdst_drop(orig_dst);
724 } else {
725 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
726 ovs_vport_name(vport), ntohs(ethertype), mru,
727 vport->dev->mtu);
728 goto err;
729 }
730
731 return;
732 err:
733 kfree_skb(skb);
734 }
735
736 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
737 struct sw_flow_key *key)
738 {
739 struct vport *vport = ovs_vport_rcu(dp, out_port);
740
741 if (likely(vport)) {
742 u16 mru = OVS_CB(skb)->mru;
743
744 if (likely(!mru || (skb->len <= mru + ETH_HLEN))) {
745 ovs_vport_send(vport, skb);
746 } else if (mru <= vport->dev->mtu) {
747 struct net *net = read_pnet(&dp->net);
748 __be16 ethertype = key->eth.type;
749
750 if (!is_flow_key_valid(key)) {
751 if (eth_p_mpls(skb->protocol))
752 ethertype = skb->inner_protocol;
753 else
754 ethertype = vlan_get_protocol(skb);
755 }
756
757 ovs_fragment(net, vport, skb, mru, ethertype);
758 } else {
759 kfree_skb(skb);
760 }
761 } else {
762 kfree_skb(skb);
763 }
764 }
765
766 static int output_userspace(struct datapath *dp, struct sk_buff *skb,
767 struct sw_flow_key *key, const struct nlattr *attr,
768 const struct nlattr *actions, int actions_len)
769 {
770 struct dp_upcall_info upcall;
771 const struct nlattr *a;
772 int rem;
773
774 memset(&upcall, 0, sizeof(upcall));
775 upcall.cmd = OVS_PACKET_CMD_ACTION;
776 upcall.mru = OVS_CB(skb)->mru;
777
778 for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
779 a = nla_next(a, &rem)) {
780 switch (nla_type(a)) {
781 case OVS_USERSPACE_ATTR_USERDATA:
782 upcall.userdata = a;
783 break;
784
785 case OVS_USERSPACE_ATTR_PID:
786 upcall.portid = nla_get_u32(a);
787 break;
788
789 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
790 /* Get out tunnel info. */
791 struct vport *vport;
792
793 vport = ovs_vport_rcu(dp, nla_get_u32(a));
794 if (vport) {
795 int err;
796
797 err = dev_fill_metadata_dst(vport->dev, skb);
798 if (!err)
799 upcall.egress_tun_info = skb_tunnel_info(skb);
800 }
801
802 break;
803 }
804
805 case OVS_USERSPACE_ATTR_ACTIONS: {
806 /* Include actions. */
807 upcall.actions = actions;
808 upcall.actions_len = actions_len;
809 break;
810 }
811
812 } /* End of switch. */
813 }
814
815 return ovs_dp_upcall(dp, skb, key, &upcall);
816 }
817
818 static int sample(struct datapath *dp, struct sk_buff *skb,
819 struct sw_flow_key *key, const struct nlattr *attr,
820 const struct nlattr *actions, int actions_len)
821 {
822 const struct nlattr *acts_list = NULL;
823 const struct nlattr *a;
824 int rem;
825
826 for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
827 a = nla_next(a, &rem)) {
828 u32 probability;
829
830 switch (nla_type(a)) {
831 case OVS_SAMPLE_ATTR_PROBABILITY:
832 probability = nla_get_u32(a);
833 if (!probability || prandom_u32() > probability)
834 return 0;
835 break;
836
837 case OVS_SAMPLE_ATTR_ACTIONS:
838 acts_list = a;
839 break;
840 }
841 }
842
843 rem = nla_len(acts_list);
844 a = nla_data(acts_list);
845
846 /* Actions list is empty, do nothing */
847 if (unlikely(!rem))
848 return 0;
849
850 /* The only known usage of sample action is having a single user-space
851 * action. Treat this usage as a special case.
852 * The output_userspace() should clone the skb to be sent to the
853 * user space. This skb will be consumed by its caller.
854 */
855 if (likely(nla_type(a) == OVS_ACTION_ATTR_USERSPACE &&
856 nla_is_last(a, rem)))
857 return output_userspace(dp, skb, key, a, actions, actions_len);
858
859 skb = skb_clone(skb, GFP_ATOMIC);
860 if (!skb)
861 /* Skip the sample action when out of memory. */
862 return 0;
863
864 if (!add_deferred_actions(skb, key, a)) {
865 if (net_ratelimit())
866 pr_warn("%s: deferred actions limit reached, dropping sample action\n",
867 ovs_dp_name(dp));
868
869 kfree_skb(skb);
870 }
871 return 0;
872 }
873
874 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
875 const struct nlattr *attr)
876 {
877 struct ovs_action_hash *hash_act = nla_data(attr);
878 u32 hash = 0;
879
880 /* OVS_HASH_ALG_L4 is the only possible hash algorithm. */
881 hash = skb_get_hash(skb);
882 hash = jhash_1word(hash, hash_act->hash_basis);
883 if (!hash)
884 hash = 0x1;
885
886 key->ovs_flow_hash = hash;
887 }
888
889 static int execute_set_action(struct sk_buff *skb,
890 struct sw_flow_key *flow_key,
891 const struct nlattr *a)
892 {
893 /* Only tunnel set execution is supported without a mask. */
894 if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
895 struct ovs_tunnel_info *tun = nla_data(a);
896
897 skb_dst_drop(skb);
898 dst_hold((struct dst_entry *)tun->tun_dst);
899 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
900 return 0;
901 }
902
903 return -EINVAL;
904 }
905
906 /* Mask is at the midpoint of the data. */
907 #define get_mask(a, type) ((const type)nla_data(a) + 1)
908
909 static int execute_masked_set_action(struct sk_buff *skb,
910 struct sw_flow_key *flow_key,
911 const struct nlattr *a)
912 {
913 int err = 0;
914
915 switch (nla_type(a)) {
916 case OVS_KEY_ATTR_PRIORITY:
917 OVS_SET_MASKED(skb->priority, nla_get_u32(a),
918 *get_mask(a, u32 *));
919 flow_key->phy.priority = skb->priority;
920 break;
921
922 case OVS_KEY_ATTR_SKB_MARK:
923 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
924 flow_key->phy.skb_mark = skb->mark;
925 break;
926
927 case OVS_KEY_ATTR_TUNNEL_INFO:
928 /* Masked data not supported for tunnel. */
929 err = -EINVAL;
930 break;
931
932 case OVS_KEY_ATTR_ETHERNET:
933 err = set_eth_addr(skb, flow_key, nla_data(a),
934 get_mask(a, struct ovs_key_ethernet *));
935 break;
936
937 case OVS_KEY_ATTR_IPV4:
938 err = set_ipv4(skb, flow_key, nla_data(a),
939 get_mask(a, struct ovs_key_ipv4 *));
940 break;
941
942 case OVS_KEY_ATTR_IPV6:
943 err = set_ipv6(skb, flow_key, nla_data(a),
944 get_mask(a, struct ovs_key_ipv6 *));
945 break;
946
947 case OVS_KEY_ATTR_TCP:
948 err = set_tcp(skb, flow_key, nla_data(a),
949 get_mask(a, struct ovs_key_tcp *));
950 break;
951
952 case OVS_KEY_ATTR_UDP:
953 err = set_udp(skb, flow_key, nla_data(a),
954 get_mask(a, struct ovs_key_udp *));
955 break;
956
957 case OVS_KEY_ATTR_SCTP:
958 err = set_sctp(skb, flow_key, nla_data(a),
959 get_mask(a, struct ovs_key_sctp *));
960 break;
961
962 case OVS_KEY_ATTR_MPLS:
963 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
964 __be32 *));
965 break;
966
967 case OVS_KEY_ATTR_CT_STATE:
968 case OVS_KEY_ATTR_CT_ZONE:
969 case OVS_KEY_ATTR_CT_MARK:
970 case OVS_KEY_ATTR_CT_LABELS:
971 err = -EINVAL;
972 break;
973 }
974
975 return err;
976 }
977
978 static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
979 struct sw_flow_key *key,
980 const struct nlattr *a, int rem)
981 {
982 struct deferred_action *da;
983
984 if (!is_flow_key_valid(key)) {
985 int err;
986
987 err = ovs_flow_key_update(skb, key);
988 if (err)
989 return err;
990 }
991 BUG_ON(!is_flow_key_valid(key));
992
993 if (!nla_is_last(a, rem)) {
994 /* Recirc action is the not the last action
995 * of the action list, need to clone the skb.
996 */
997 skb = skb_clone(skb, GFP_ATOMIC);
998
999 /* Skip the recirc action when out of memory, but
1000 * continue on with the rest of the action list.
1001 */
1002 if (!skb)
1003 return 0;
1004 }
1005
1006 da = add_deferred_actions(skb, key, NULL);
1007 if (da) {
1008 da->pkt_key.recirc_id = nla_get_u32(a);
1009 } else {
1010 kfree_skb(skb);
1011
1012 if (net_ratelimit())
1013 pr_warn("%s: deferred action limit reached, drop recirc action\n",
1014 ovs_dp_name(dp));
1015 }
1016
1017 return 0;
1018 }
1019
1020 /* Execute a list of actions against 'skb'. */
1021 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
1022 struct sw_flow_key *key,
1023 const struct nlattr *attr, int len)
1024 {
1025 /* Every output action needs a separate clone of 'skb', but the common
1026 * case is just a single output action, so that doing a clone and
1027 * then freeing the original skbuff is wasteful. So the following code
1028 * is slightly obscure just to avoid that.
1029 */
1030 int prev_port = -1;
1031 const struct nlattr *a;
1032 int rem;
1033
1034 for (a = attr, rem = len; rem > 0;
1035 a = nla_next(a, &rem)) {
1036 int err = 0;
1037
1038 if (unlikely(prev_port != -1)) {
1039 struct sk_buff *out_skb = skb_clone(skb, GFP_ATOMIC);
1040
1041 if (out_skb)
1042 do_output(dp, out_skb, prev_port, key);
1043
1044 prev_port = -1;
1045 }
1046
1047 switch (nla_type(a)) {
1048 case OVS_ACTION_ATTR_OUTPUT:
1049 prev_port = nla_get_u32(a);
1050 break;
1051
1052 case OVS_ACTION_ATTR_USERSPACE:
1053 output_userspace(dp, skb, key, a, attr, len);
1054 break;
1055
1056 case OVS_ACTION_ATTR_HASH:
1057 execute_hash(skb, key, a);
1058 break;
1059
1060 case OVS_ACTION_ATTR_PUSH_MPLS:
1061 err = push_mpls(skb, key, nla_data(a));
1062 break;
1063
1064 case OVS_ACTION_ATTR_POP_MPLS:
1065 err = pop_mpls(skb, key, nla_get_be16(a));
1066 break;
1067
1068 case OVS_ACTION_ATTR_PUSH_VLAN:
1069 err = push_vlan(skb, key, nla_data(a));
1070 break;
1071
1072 case OVS_ACTION_ATTR_POP_VLAN:
1073 err = pop_vlan(skb, key);
1074 break;
1075
1076 case OVS_ACTION_ATTR_RECIRC:
1077 err = execute_recirc(dp, skb, key, a, rem);
1078 if (nla_is_last(a, rem)) {
1079 /* If this is the last action, the skb has
1080 * been consumed or freed.
1081 * Return immediately.
1082 */
1083 return err;
1084 }
1085 break;
1086
1087 case OVS_ACTION_ATTR_SET:
1088 err = execute_set_action(skb, key, nla_data(a));
1089 break;
1090
1091 case OVS_ACTION_ATTR_SET_MASKED:
1092 case OVS_ACTION_ATTR_SET_TO_MASKED:
1093 err = execute_masked_set_action(skb, key, nla_data(a));
1094 break;
1095
1096 case OVS_ACTION_ATTR_SAMPLE:
1097 err = sample(dp, skb, key, a, attr, len);
1098 break;
1099
1100 case OVS_ACTION_ATTR_CT:
1101 if (!is_flow_key_valid(key)) {
1102 err = ovs_flow_key_update(skb, key);
1103 if (err)
1104 return err;
1105 }
1106
1107 err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
1108 nla_data(a));
1109
1110 /* Hide stolen IP fragments from user space. */
1111 if (err)
1112 return err == -EINPROGRESS ? 0 : err;
1113 break;
1114 }
1115
1116 if (unlikely(err)) {
1117 kfree_skb(skb);
1118 return err;
1119 }
1120 }
1121
1122 if (prev_port != -1)
1123 do_output(dp, skb, prev_port, key);
1124 else
1125 consume_skb(skb);
1126
1127 return 0;
1128 }
1129
1130 static void process_deferred_actions(struct datapath *dp)
1131 {
1132 struct action_fifo *fifo = this_cpu_ptr(action_fifos);
1133
1134 /* Do not touch the FIFO in case there is no deferred actions. */
1135 if (action_fifo_is_empty(fifo))
1136 return;
1137
1138 /* Finishing executing all deferred actions. */
1139 do {
1140 struct deferred_action *da = action_fifo_get(fifo);
1141 struct sk_buff *skb = da->skb;
1142 struct sw_flow_key *key = &da->pkt_key;
1143 const struct nlattr *actions = da->actions;
1144
1145 if (actions)
1146 do_execute_actions(dp, skb, key, actions,
1147 nla_len(actions));
1148 else
1149 ovs_dp_process_packet(skb, key);
1150 } while (!action_fifo_is_empty(fifo));
1151
1152 /* Reset FIFO for the next packet. */
1153 action_fifo_init(fifo);
1154 }
1155
1156 /* Execute a list of actions against 'skb'. */
1157 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
1158 const struct sw_flow_actions *acts,
1159 struct sw_flow_key *key)
1160 {
1161 static const int ovs_recursion_limit = 5;
1162 int err, level;
1163
1164 level = __this_cpu_inc_return(exec_actions_level);
1165 if (unlikely(level > ovs_recursion_limit)) {
1166 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
1167 ovs_dp_name(dp));
1168 kfree_skb(skb);
1169 err = -ENETDOWN;
1170 goto out;
1171 }
1172
1173 err = do_execute_actions(dp, skb, key,
1174 acts->actions, acts->actions_len);
1175
1176 if (level == 1)
1177 process_deferred_actions(dp);
1178
1179 out:
1180 __this_cpu_dec(exec_actions_level);
1181 return err;
1182 }
1183
1184 int action_fifos_init(void)
1185 {
1186 action_fifos = alloc_percpu(struct action_fifo);
1187 if (!action_fifos)
1188 return -ENOMEM;
1189
1190 return 0;
1191 }
1192
1193 void action_fifos_exit(void)
1194 {
1195 free_percpu(action_fifos);
1196 }
Linux with added FPC-III support