s390: fix restore of invalid floating-point-control
[firefly-linux-kernel-4.4.55.git] / net / openvswitch / actions.c
1 /*
2  * Copyright (c) 2007-2013 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/sctp.h>
26 #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>
32 #include <net/ipv6.h>
33 #include <net/checksum.h>
34 #include <net/dsfield.h>
35 #include <net/sctp/checksum.h>
36
37 #include "datapath.h"
38 #include "vport.h"
39
40 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
41                         const struct nlattr *attr, int len, bool keep_skb);
42
43 static 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
51 /* remove VLAN header from packet and update csum accordingly. */
52 static 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
63                                         + (2 * ETH_ALEN), VLAN_HLEN, 0));
64
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
78 static 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
103         __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), ntohs(tci));
104         return 0;
105 }
106
107 static 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
115                 if (!__vlan_put_tag(skb, skb->vlan_proto, current_tag))
116                         return -ENOMEM;
117
118                 if (skb->ip_summed == CHECKSUM_COMPLETE)
119                         skb->csum = csum_add(skb->csum, csum_partial(skb->data
120                                         + (2 * ETH_ALEN), VLAN_HLEN, 0));
121
122         }
123         __vlan_hwaccel_put_tag(skb, vlan->vlan_tpid, ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
124         return 0;
125 }
126
127 static 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
135         skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
136
137         ether_addr_copy(eth_hdr(skb)->h_source, eth_key->eth_src);
138         ether_addr_copy(eth_hdr(skb)->h_dest, eth_key->eth_dst);
139
140         ovs_skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
141
142         return 0;
143 }
144
145 static 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) {
155                 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                 }
165         }
166
167         csum_replace4(&nh->check, *addr, new_addr);
168         skb_clear_hash(skb);
169         *addr = new_addr;
170 }
171
172 static 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
195 static 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_clear_hash(skb);
203         memcpy(addr, new_addr, sizeof(__be32[4]));
204 }
205
206 static 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
212 static 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
219 static 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
225 static 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
252 static 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
293 /* Must follow make_writable() since that can move the skb data. */
294 static 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_clear_hash(skb);
300 }
301
302 static 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_clear_hash(skb);
314         }
315 }
316
317 static int set_udp(struct sk_buff *skb, const struct ovs_key_udp *udp_port_key)
318 {
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)
329                 set_udp_port(skb, &uh->source, udp_port_key->udp_src);
330
331         if (udp_port_key->udp_dst != uh->dest)
332                 set_udp_port(skb, &uh->dest, udp_port_key->udp_dst);
333
334         return 0;
335 }
336
337 static int set_tcp(struct sk_buff *skb, const struct ovs_key_tcp *tcp_port_key)
338 {
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
357 static 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_clear_hash(skb);
385         }
386
387         return 0;
388 }
389
390 static 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
397         vport = ovs_vport_rcu(dp, out_port);
398         if (unlikely(!vport)) {
399                 kfree_skb(skb);
400                 return -ENODEV;
401         }
402
403         ovs_vport_send(vport, skb);
404         return 0;
405 }
406
407 static 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
414         BUG_ON(!OVS_CB(skb)->pkt_key);
415
416         upcall.cmd = OVS_PACKET_CMD_ACTION;
417         upcall.key = OVS_CB(skb)->pkt_key;
418         upcall.userdata = NULL;
419         upcall.portid = 0;
420
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:
429                         upcall.portid = nla_get_u32(a);
430                         break;
431                 }
432         }
433
434         return ovs_dp_upcall(dp, skb, &upcall);
435 }
436
437 static 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 (prandom_u32() >= 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
462 static 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
472         case OVS_KEY_ATTR_SKB_MARK:
473                 skb->mark = nla_get_u32(nested_attr);
474                 break;
475
476         case OVS_KEY_ATTR_IPV4_TUNNEL:
477                 OVS_CB(skb)->tun_key = nla_data(nested_attr);
478                 break;
479
480         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
488         case OVS_KEY_ATTR_IPV6:
489                 err = set_ipv6(skb, nla_data(nested_attr));
490                 break;
491
492         case OVS_KEY_ATTR_TCP:
493                 err = set_tcp(skb, nla_data(nested_attr));
494                 break;
495
496         case OVS_KEY_ATTR_UDP:
497                 err = set_udp(skb, nla_data(nested_attr));
498                 break;
499
500         case OVS_KEY_ATTR_SCTP:
501                 err = set_sctp(skb, nla_data(nested_attr));
502                 break;
503         }
504
505         return err;
506 }
507
508 /* Execute a list of actions against 'skb'. */
509 static 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'. */
575 int 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
579         OVS_CB(skb)->tun_key = NULL;
580         return do_execute_actions(dp, skb, acts->actions,
581                                          acts->actions_len, false);
582 }