blob: 65cfaa816075c93d933d4c6e17d13eaf6e92546f [file] [log] [blame]
Jesse Grossccb13522011-10-25 19:26:31 -07001/*
Andy Zhou03f0d912013-08-07 20:01:00 -07002 * Copyright (c) 2007-2013 Nicira, Inc.
Jesse Grossccb13522011-10-25 19:26:31 -07003 *
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>
Joe Stringera175a722013-08-22 12:30:48 -070025#include <linux/sctp.h>
Jesse Grossccb13522011-10-25 19:26:31 -070026#include <linux/tcp.h>
27#include <linux/udp.h>
28#include <linux/in6.h>
29#include <linux/if_arp.h>
30#include <linux/if_vlan.h>
31#include <net/ip.h>
Ansis Atteka3fdbd1c2012-11-13 15:44:14 -080032#include <net/ipv6.h>
Jesse Grossccb13522011-10-25 19:26:31 -070033#include <net/checksum.h>
34#include <net/dsfield.h>
Joe Stringera175a722013-08-22 12:30:48 -070035#include <net/sctp/checksum.h>
Jesse Grossccb13522011-10-25 19:26:31 -070036
37#include "datapath.h"
38#include "vport.h"
39
40static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
41 const struct nlattr *attr, int len, bool keep_skb);
42
43static int make_writable(struct sk_buff *skb, int write_len)
44{
45 if (!skb_cloned(skb) || skb_clone_writable(skb, write_len))
46 return 0;
47
48 return pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
49}
50
Joe Stringer39855b52012-08-31 15:28:28 -070051/* remove VLAN header from packet and update csum accordingly. */
Jesse Grossccb13522011-10-25 19:26:31 -070052static int __pop_vlan_tci(struct sk_buff *skb, __be16 *current_tci)
53{
54 struct vlan_hdr *vhdr;
55 int err;
56
57 err = make_writable(skb, VLAN_ETH_HLEN);
58 if (unlikely(err))
59 return err;
60
61 if (skb->ip_summed == CHECKSUM_COMPLETE)
62 skb->csum = csum_sub(skb->csum, csum_partial(skb->data
Cong Wang7b024082013-02-22 17:32:26 +080063 + (2 * ETH_ALEN), VLAN_HLEN, 0));
Jesse Grossccb13522011-10-25 19:26:31 -070064
65 vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN);
66 *current_tci = vhdr->h_vlan_TCI;
67
68 memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN);
69 __skb_pull(skb, VLAN_HLEN);
70
71 vlan_set_encap_proto(skb, vhdr);
72 skb->mac_header += VLAN_HLEN;
73 skb_reset_mac_len(skb);
74
75 return 0;
76}
77
78static int pop_vlan(struct sk_buff *skb)
79{
80 __be16 tci;
81 int err;
82
83 if (likely(vlan_tx_tag_present(skb))) {
84 skb->vlan_tci = 0;
85 } else {
86 if (unlikely(skb->protocol != htons(ETH_P_8021Q) ||
87 skb->len < VLAN_ETH_HLEN))
88 return 0;
89
90 err = __pop_vlan_tci(skb, &tci);
91 if (err)
92 return err;
93 }
94 /* move next vlan tag to hw accel tag */
95 if (likely(skb->protocol != htons(ETH_P_8021Q) ||
96 skb->len < VLAN_ETH_HLEN))
97 return 0;
98
99 err = __pop_vlan_tci(skb, &tci);
100 if (unlikely(err))
101 return err;
102
Patrick McHardy86a9bad2013-04-19 02:04:30 +0000103 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), ntohs(tci));
Jesse Grossccb13522011-10-25 19:26:31 -0700104 return 0;
105}
106
107static int push_vlan(struct sk_buff *skb, const struct ovs_action_push_vlan *vlan)
108{
109 if (unlikely(vlan_tx_tag_present(skb))) {
110 u16 current_tag;
111
112 /* push down current VLAN tag */
113 current_tag = vlan_tx_tag_get(skb);
114
Patrick McHardy86a9bad2013-04-19 02:04:30 +0000115 if (!__vlan_put_tag(skb, skb->vlan_proto, current_tag))
Jesse Grossccb13522011-10-25 19:26:31 -0700116 return -ENOMEM;
117
118 if (skb->ip_summed == CHECKSUM_COMPLETE)
119 skb->csum = csum_add(skb->csum, csum_partial(skb->data
Cong Wang7b024082013-02-22 17:32:26 +0800120 + (2 * ETH_ALEN), VLAN_HLEN, 0));
Jesse Grossccb13522011-10-25 19:26:31 -0700121
122 }
Patrick McHardy86a9bad2013-04-19 02:04:30 +0000123 __vlan_hwaccel_put_tag(skb, vlan->vlan_tpid, ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
Jesse Grossccb13522011-10-25 19:26:31 -0700124 return 0;
125}
126
127static int set_eth_addr(struct sk_buff *skb,
128 const struct ovs_key_ethernet *eth_key)
129{
130 int err;
131 err = make_writable(skb, ETH_HLEN);
132 if (unlikely(err))
133 return err;
134
Pravin B Shelarb34df5e2013-06-13 11:11:44 -0700135 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
136
Jesse Grossccb13522011-10-25 19:26:31 -0700137 memcpy(eth_hdr(skb)->h_source, eth_key->eth_src, ETH_ALEN);
138 memcpy(eth_hdr(skb)->h_dest, eth_key->eth_dst, ETH_ALEN);
139
Pravin B Shelarb34df5e2013-06-13 11:11:44 -0700140 ovs_skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
141
Jesse Grossccb13522011-10-25 19:26:31 -0700142 return 0;
143}
144
145static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
146 __be32 *addr, __be32 new_addr)
147{
148 int transport_len = skb->len - skb_transport_offset(skb);
149
150 if (nh->protocol == IPPROTO_TCP) {
151 if (likely(transport_len >= sizeof(struct tcphdr)))
152 inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
153 *addr, new_addr, 1);
154 } else if (nh->protocol == IPPROTO_UDP) {
Jesse Gross81e5d412012-03-06 15:05:46 -0800155 if (likely(transport_len >= sizeof(struct udphdr))) {
156 struct udphdr *uh = udp_hdr(skb);
157
158 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
159 inet_proto_csum_replace4(&uh->check, skb,
160 *addr, new_addr, 1);
161 if (!uh->check)
162 uh->check = CSUM_MANGLED_0;
163 }
164 }
Jesse Grossccb13522011-10-25 19:26:31 -0700165 }
166
167 csum_replace4(&nh->check, *addr, new_addr);
168 skb->rxhash = 0;
169 *addr = new_addr;
170}
171
Ansis Atteka3fdbd1c2012-11-13 15:44:14 -0800172static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
173 __be32 addr[4], const __be32 new_addr[4])
174{
175 int transport_len = skb->len - skb_transport_offset(skb);
176
177 if (l4_proto == IPPROTO_TCP) {
178 if (likely(transport_len >= sizeof(struct tcphdr)))
179 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
180 addr, new_addr, 1);
181 } else if (l4_proto == IPPROTO_UDP) {
182 if (likely(transport_len >= sizeof(struct udphdr))) {
183 struct udphdr *uh = udp_hdr(skb);
184
185 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
186 inet_proto_csum_replace16(&uh->check, skb,
187 addr, new_addr, 1);
188 if (!uh->check)
189 uh->check = CSUM_MANGLED_0;
190 }
191 }
192 }
193}
194
195static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
196 __be32 addr[4], const __be32 new_addr[4],
197 bool recalculate_csum)
198{
199 if (recalculate_csum)
200 update_ipv6_checksum(skb, l4_proto, addr, new_addr);
201
202 skb->rxhash = 0;
203 memcpy(addr, new_addr, sizeof(__be32[4]));
204}
205
206static void set_ipv6_tc(struct ipv6hdr *nh, u8 tc)
207{
208 nh->priority = tc >> 4;
209 nh->flow_lbl[0] = (nh->flow_lbl[0] & 0x0F) | ((tc & 0x0F) << 4);
210}
211
212static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl)
213{
214 nh->flow_lbl[0] = (nh->flow_lbl[0] & 0xF0) | (fl & 0x000F0000) >> 16;
215 nh->flow_lbl[1] = (fl & 0x0000FF00) >> 8;
216 nh->flow_lbl[2] = fl & 0x000000FF;
217}
218
Jesse Grossccb13522011-10-25 19:26:31 -0700219static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl)
220{
221 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
222 nh->ttl = new_ttl;
223}
224
225static int set_ipv4(struct sk_buff *skb, const struct ovs_key_ipv4 *ipv4_key)
226{
227 struct iphdr *nh;
228 int err;
229
230 err = make_writable(skb, skb_network_offset(skb) +
231 sizeof(struct iphdr));
232 if (unlikely(err))
233 return err;
234
235 nh = ip_hdr(skb);
236
237 if (ipv4_key->ipv4_src != nh->saddr)
238 set_ip_addr(skb, nh, &nh->saddr, ipv4_key->ipv4_src);
239
240 if (ipv4_key->ipv4_dst != nh->daddr)
241 set_ip_addr(skb, nh, &nh->daddr, ipv4_key->ipv4_dst);
242
243 if (ipv4_key->ipv4_tos != nh->tos)
244 ipv4_change_dsfield(nh, 0, ipv4_key->ipv4_tos);
245
246 if (ipv4_key->ipv4_ttl != nh->ttl)
247 set_ip_ttl(skb, nh, ipv4_key->ipv4_ttl);
248
249 return 0;
250}
251
Ansis Atteka3fdbd1c2012-11-13 15:44:14 -0800252static int set_ipv6(struct sk_buff *skb, const struct ovs_key_ipv6 *ipv6_key)
253{
254 struct ipv6hdr *nh;
255 int err;
256 __be32 *saddr;
257 __be32 *daddr;
258
259 err = make_writable(skb, skb_network_offset(skb) +
260 sizeof(struct ipv6hdr));
261 if (unlikely(err))
262 return err;
263
264 nh = ipv6_hdr(skb);
265 saddr = (__be32 *)&nh->saddr;
266 daddr = (__be32 *)&nh->daddr;
267
268 if (memcmp(ipv6_key->ipv6_src, saddr, sizeof(ipv6_key->ipv6_src)))
269 set_ipv6_addr(skb, ipv6_key->ipv6_proto, saddr,
270 ipv6_key->ipv6_src, true);
271
272 if (memcmp(ipv6_key->ipv6_dst, daddr, sizeof(ipv6_key->ipv6_dst))) {
273 unsigned int offset = 0;
274 int flags = IP6_FH_F_SKIP_RH;
275 bool recalc_csum = true;
276
277 if (ipv6_ext_hdr(nh->nexthdr))
278 recalc_csum = ipv6_find_hdr(skb, &offset,
279 NEXTHDR_ROUTING, NULL,
280 &flags) != NEXTHDR_ROUTING;
281
282 set_ipv6_addr(skb, ipv6_key->ipv6_proto, daddr,
283 ipv6_key->ipv6_dst, recalc_csum);
284 }
285
286 set_ipv6_tc(nh, ipv6_key->ipv6_tclass);
287 set_ipv6_fl(nh, ntohl(ipv6_key->ipv6_label));
288 nh->hop_limit = ipv6_key->ipv6_hlimit;
289
290 return 0;
291}
292
Jesse Grossccb13522011-10-25 19:26:31 -0700293/* Must follow make_writable() since that can move the skb data. */
294static void set_tp_port(struct sk_buff *skb, __be16 *port,
295 __be16 new_port, __sum16 *check)
296{
297 inet_proto_csum_replace2(check, skb, *port, new_port, 0);
298 *port = new_port;
299 skb->rxhash = 0;
300}
301
Jesse Gross81e5d412012-03-06 15:05:46 -0800302static void set_udp_port(struct sk_buff *skb, __be16 *port, __be16 new_port)
303{
304 struct udphdr *uh = udp_hdr(skb);
305
306 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
307 set_tp_port(skb, port, new_port, &uh->check);
308
309 if (!uh->check)
310 uh->check = CSUM_MANGLED_0;
311 } else {
312 *port = new_port;
313 skb->rxhash = 0;
314 }
315}
316
317static int set_udp(struct sk_buff *skb, const struct ovs_key_udp *udp_port_key)
Jesse Grossccb13522011-10-25 19:26:31 -0700318{
319 struct udphdr *uh;
320 int err;
321
322 err = make_writable(skb, skb_transport_offset(skb) +
323 sizeof(struct udphdr));
324 if (unlikely(err))
325 return err;
326
327 uh = udp_hdr(skb);
328 if (udp_port_key->udp_src != uh->source)
Jesse Gross81e5d412012-03-06 15:05:46 -0800329 set_udp_port(skb, &uh->source, udp_port_key->udp_src);
Jesse Grossccb13522011-10-25 19:26:31 -0700330
331 if (udp_port_key->udp_dst != uh->dest)
Jesse Gross81e5d412012-03-06 15:05:46 -0800332 set_udp_port(skb, &uh->dest, udp_port_key->udp_dst);
Jesse Grossccb13522011-10-25 19:26:31 -0700333
334 return 0;
335}
336
Jesse Gross81e5d412012-03-06 15:05:46 -0800337static int set_tcp(struct sk_buff *skb, const struct ovs_key_tcp *tcp_port_key)
Jesse Grossccb13522011-10-25 19:26:31 -0700338{
339 struct tcphdr *th;
340 int err;
341
342 err = make_writable(skb, skb_transport_offset(skb) +
343 sizeof(struct tcphdr));
344 if (unlikely(err))
345 return err;
346
347 th = tcp_hdr(skb);
348 if (tcp_port_key->tcp_src != th->source)
349 set_tp_port(skb, &th->source, tcp_port_key->tcp_src, &th->check);
350
351 if (tcp_port_key->tcp_dst != th->dest)
352 set_tp_port(skb, &th->dest, tcp_port_key->tcp_dst, &th->check);
353
354 return 0;
355}
356
Joe Stringera175a722013-08-22 12:30:48 -0700357static int set_sctp(struct sk_buff *skb,
358 const struct ovs_key_sctp *sctp_port_key)
359{
360 struct sctphdr *sh;
361 int err;
362 unsigned int sctphoff = skb_transport_offset(skb);
363
364 err = make_writable(skb, sctphoff + sizeof(struct sctphdr));
365 if (unlikely(err))
366 return err;
367
368 sh = sctp_hdr(skb);
369 if (sctp_port_key->sctp_src != sh->source ||
370 sctp_port_key->sctp_dst != sh->dest) {
371 __le32 old_correct_csum, new_csum, old_csum;
372
373 old_csum = sh->checksum;
374 old_correct_csum = sctp_compute_cksum(skb, sctphoff);
375
376 sh->source = sctp_port_key->sctp_src;
377 sh->dest = sctp_port_key->sctp_dst;
378
379 new_csum = sctp_compute_cksum(skb, sctphoff);
380
381 /* Carry any checksum errors through. */
382 sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
383
384 skb->rxhash = 0;
385 }
386
387 return 0;
388}
389
Jesse Grossccb13522011-10-25 19:26:31 -0700390static int do_output(struct datapath *dp, struct sk_buff *skb, int out_port)
391{
392 struct vport *vport;
393
394 if (unlikely(!skb))
395 return -ENOMEM;
396
Pravin B Shelar15eac2a2012-08-23 12:40:54 -0700397 vport = ovs_vport_rcu(dp, out_port);
Jesse Grossccb13522011-10-25 19:26:31 -0700398 if (unlikely(!vport)) {
399 kfree_skb(skb);
400 return -ENODEV;
401 }
402
403 ovs_vport_send(vport, skb);
404 return 0;
405}
406
407static int output_userspace(struct datapath *dp, struct sk_buff *skb,
408 const struct nlattr *attr)
409{
410 struct dp_upcall_info upcall;
411 const struct nlattr *a;
412 int rem;
413
Andy Zhou03f0d912013-08-07 20:01:00 -0700414 BUG_ON(!OVS_CB(skb)->pkt_key);
415
Jesse Grossccb13522011-10-25 19:26:31 -0700416 upcall.cmd = OVS_PACKET_CMD_ACTION;
Andy Zhou03f0d912013-08-07 20:01:00 -0700417 upcall.key = OVS_CB(skb)->pkt_key;
Jesse Grossccb13522011-10-25 19:26:31 -0700418 upcall.userdata = NULL;
Eric W. Biederman15e47302012-09-07 20:12:54 +0000419 upcall.portid = 0;
Jesse Grossccb13522011-10-25 19:26:31 -0700420
421 for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
422 a = nla_next(a, &rem)) {
423 switch (nla_type(a)) {
424 case OVS_USERSPACE_ATTR_USERDATA:
425 upcall.userdata = a;
426 break;
427
428 case OVS_USERSPACE_ATTR_PID:
Eric W. Biederman15e47302012-09-07 20:12:54 +0000429 upcall.portid = nla_get_u32(a);
Jesse Grossccb13522011-10-25 19:26:31 -0700430 break;
431 }
432 }
433
434 return ovs_dp_upcall(dp, skb, &upcall);
435}
436
437static int sample(struct datapath *dp, struct sk_buff *skb,
438 const struct nlattr *attr)
439{
440 const struct nlattr *acts_list = NULL;
441 const struct nlattr *a;
442 int rem;
443
444 for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
445 a = nla_next(a, &rem)) {
446 switch (nla_type(a)) {
447 case OVS_SAMPLE_ATTR_PROBABILITY:
448 if (net_random() >= nla_get_u32(a))
449 return 0;
450 break;
451
452 case OVS_SAMPLE_ATTR_ACTIONS:
453 acts_list = a;
454 break;
455 }
456 }
457
458 return do_execute_actions(dp, skb, nla_data(acts_list),
459 nla_len(acts_list), true);
460}
461
462static int execute_set_action(struct sk_buff *skb,
463 const struct nlattr *nested_attr)
464{
465 int err = 0;
466
467 switch (nla_type(nested_attr)) {
468 case OVS_KEY_ATTR_PRIORITY:
469 skb->priority = nla_get_u32(nested_attr);
470 break;
471
Ansis Atteka39c7caeb2012-11-26 11:24:11 -0800472 case OVS_KEY_ATTR_SKB_MARK:
473 skb->mark = nla_get_u32(nested_attr);
474 break;
475
Pravin B Shelar7d5437c2013-06-17 17:50:18 -0700476 case OVS_KEY_ATTR_IPV4_TUNNEL:
477 OVS_CB(skb)->tun_key = nla_data(nested_attr);
478 break;
479
Jesse Grossccb13522011-10-25 19:26:31 -0700480 case OVS_KEY_ATTR_ETHERNET:
481 err = set_eth_addr(skb, nla_data(nested_attr));
482 break;
483
484 case OVS_KEY_ATTR_IPV4:
485 err = set_ipv4(skb, nla_data(nested_attr));
486 break;
487
Ansis Atteka3fdbd1c2012-11-13 15:44:14 -0800488 case OVS_KEY_ATTR_IPV6:
489 err = set_ipv6(skb, nla_data(nested_attr));
490 break;
491
Jesse Grossccb13522011-10-25 19:26:31 -0700492 case OVS_KEY_ATTR_TCP:
Jesse Gross81e5d412012-03-06 15:05:46 -0800493 err = set_tcp(skb, nla_data(nested_attr));
Jesse Grossccb13522011-10-25 19:26:31 -0700494 break;
495
496 case OVS_KEY_ATTR_UDP:
Jesse Gross81e5d412012-03-06 15:05:46 -0800497 err = set_udp(skb, nla_data(nested_attr));
Jesse Grossccb13522011-10-25 19:26:31 -0700498 break;
Joe Stringera175a722013-08-22 12:30:48 -0700499
500 case OVS_KEY_ATTR_SCTP:
501 err = set_sctp(skb, nla_data(nested_attr));
502 break;
Jesse Grossccb13522011-10-25 19:26:31 -0700503 }
504
505 return err;
506}
507
508/* Execute a list of actions against 'skb'. */
509static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
510 const struct nlattr *attr, int len, bool keep_skb)
511{
512 /* Every output action needs a separate clone of 'skb', but the common
513 * case is just a single output action, so that doing a clone and
514 * then freeing the original skbuff is wasteful. So the following code
515 * is slightly obscure just to avoid that. */
516 int prev_port = -1;
517 const struct nlattr *a;
518 int rem;
519
520 for (a = attr, rem = len; rem > 0;
521 a = nla_next(a, &rem)) {
522 int err = 0;
523
524 if (prev_port != -1) {
525 do_output(dp, skb_clone(skb, GFP_ATOMIC), prev_port);
526 prev_port = -1;
527 }
528
529 switch (nla_type(a)) {
530 case OVS_ACTION_ATTR_OUTPUT:
531 prev_port = nla_get_u32(a);
532 break;
533
534 case OVS_ACTION_ATTR_USERSPACE:
535 output_userspace(dp, skb, a);
536 break;
537
538 case OVS_ACTION_ATTR_PUSH_VLAN:
539 err = push_vlan(skb, nla_data(a));
540 if (unlikely(err)) /* skb already freed. */
541 return err;
542 break;
543
544 case OVS_ACTION_ATTR_POP_VLAN:
545 err = pop_vlan(skb);
546 break;
547
548 case OVS_ACTION_ATTR_SET:
549 err = execute_set_action(skb, nla_data(a));
550 break;
551
552 case OVS_ACTION_ATTR_SAMPLE:
553 err = sample(dp, skb, a);
554 break;
555 }
556
557 if (unlikely(err)) {
558 kfree_skb(skb);
559 return err;
560 }
561 }
562
563 if (prev_port != -1) {
564 if (keep_skb)
565 skb = skb_clone(skb, GFP_ATOMIC);
566
567 do_output(dp, skb, prev_port);
568 } else if (!keep_skb)
569 consume_skb(skb);
570
571 return 0;
572}
573
574/* Execute a list of actions against 'skb'. */
575int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb)
576{
577 struct sw_flow_actions *acts = rcu_dereference(OVS_CB(skb)->flow->sf_acts);
578
Jesse Gross36bf5cc2013-08-14 15:50:36 -0700579 OVS_CB(skb)->tun_key = NULL;
Jesse Grossccb13522011-10-25 19:26:31 -0700580 return do_execute_actions(dp, skb, acts->actions,
581 acts->actions_len, false);
582}