1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2007-2017 Nicira, Inc.
4 */
5
6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7
8#include <linux/skbuff.h>
9#include <linux/in.h>
10#include <linux/ip.h>
11#include <linux/openvswitch.h>
12#include <linux/sctp.h>
13#include <linux/tcp.h>
14#include <linux/udp.h>
15#include <linux/in6.h>
16#include <linux/if_arp.h>
17#include <linux/if_vlan.h>
18
19#include <net/dst.h>
20#include <net/gso.h>
21#include <net/ip.h>
22#include <net/ipv6.h>
23#include <net/ip6_fib.h>
24#include <net/checksum.h>
25#include <net/dsfield.h>
26#include <net/mpls.h>
27#include <net/sctp/checksum.h>
28
29#include "datapath.h"
30#include "drop.h"
31#include "flow.h"
32#include "conntrack.h"
33#include "vport.h"
34#include "flow_netlink.h"
35#include "openvswitch_trace.h"
36
37struct deferred_action {
38 struct sk_buff *skb;
39 const struct nlattr *actions;
40 int actions_len;
41
42 /* Store pkt_key clone when creating deferred action. */
43 struct sw_flow_key pkt_key;
44};
45
46#define MAX_L2_LEN (VLAN_ETH_HLEN + 3 * MPLS_HLEN)
47struct ovs_frag_data {
48 unsigned long dst;
49 struct vport *vport;
50 struct ovs_skb_cb cb;
51 __be16 inner_protocol;
52 u16 network_offset; /* valid only for MPLS */
53 u16 vlan_tci;
54 __be16 vlan_proto;
55 unsigned int l2_len;
56 u8 mac_proto;
57 u8 l2_data[MAX_L2_LEN];
58};
59
60static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);
61
62#define DEFERRED_ACTION_FIFO_SIZE 10
63#define OVS_RECURSION_LIMIT 5
64#define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2)
65struct action_fifo {
66 int head;
67 int tail;
68 /* Deferred action fifo queue storage. */
69 struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
70};
71
72struct action_flow_keys {
73 struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
74};
75
76static struct action_fifo __percpu *action_fifos;
77static struct action_flow_keys __percpu *flow_keys;
78static DEFINE_PER_CPU(int, exec_actions_level);
79
80/* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys'
81 * space. Return NULL if out of key spaces.
82 */
83static struct sw_flow_key *clone_key(const struct sw_flow_key *key_)
84{
85 struct action_flow_keys *keys = this_cpu_ptr(flow_keys);
86 int level = this_cpu_read(exec_actions_level);
87 struct sw_flow_key *key = NULL;
88
89 if (level <= OVS_DEFERRED_ACTION_THRESHOLD) {
90 key = &keys->key[level - 1];
91 *key = *key_;
92 }
93
94 return key;
95}
96
97static void action_fifo_init(struct action_fifo *fifo)
98{
99 fifo->head = 0;
100 fifo->tail = 0;
101}
102
103static bool action_fifo_is_empty(const struct action_fifo *fifo)
104{
105 return (fifo->head == fifo->tail);
106}
107
108static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
109{
110 if (action_fifo_is_empty(fifo))
111 return NULL;
112
113 return &fifo->fifo[fifo->tail++];
114}
115
116static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
117{
118 if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
119 return NULL;
120
121 return &fifo->fifo[fifo->head++];
122}
123
124/* Return true if fifo is not full */
125static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
126 const struct sw_flow_key *key,
127 const struct nlattr *actions,
128 const int actions_len)
129{
130 struct action_fifo *fifo;
131 struct deferred_action *da;
132
133 fifo = this_cpu_ptr(action_fifos);
134 da = action_fifo_put(fifo);
135 if (da) {
136 da->skb = skb;
137 da->actions = actions;
138 da->actions_len = actions_len;
139 da->pkt_key = *key;
140 }
141
142 return da;
143}
144
145static void invalidate_flow_key(struct sw_flow_key *key)
146{
147 key->mac_proto |= SW_FLOW_KEY_INVALID;
148}
149
150static bool is_flow_key_valid(const struct sw_flow_key *key)
151{
152 return !(key->mac_proto & SW_FLOW_KEY_INVALID);
153}
154
155static int clone_execute(struct datapath *dp, struct sk_buff *skb,
156 struct sw_flow_key *key,
157 u32 recirc_id,
158 const struct nlattr *actions, int len,
159 bool last, bool clone_flow_key);
160
161static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
162 struct sw_flow_key *key,
163 const struct nlattr *attr, int len);
164
165static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
166 __be32 mpls_lse, __be16 mpls_ethertype, __u16 mac_len)
167{
168 int err;
169
170 err = skb_mpls_push(skb, mpls_lse, mpls_proto: mpls_ethertype, mac_len, ethernet: !!mac_len);
171 if (err)
172 return err;
173
174 if (!mac_len)
175 key->mac_proto = MAC_PROTO_NONE;
176
177 invalidate_flow_key(key);
178 return 0;
179}
180
181static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
182 const __be16 ethertype)
183{
184 int err;
185
186 err = skb_mpls_pop(skb, next_proto: ethertype, mac_len: skb->mac_len,
187 ethernet: ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET);
188 if (err)
189 return err;
190
191 if (ethertype == htons(ETH_P_TEB))
192 key->mac_proto = MAC_PROTO_ETHERNET;
193
194 invalidate_flow_key(key);
195 return 0;
196}
197
198static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
199 const __be32 *mpls_lse, const __be32 *mask)
200{
201 struct mpls_shim_hdr *stack;
202 __be32 lse;
203 int err;
204
205 if (!pskb_may_pull(skb, len: skb_network_offset(skb) + MPLS_HLEN))
206 return -ENOMEM;
207
208 stack = mpls_hdr(skb);
209 lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
210 err = skb_mpls_update_lse(skb, mpls_lse: lse);
211 if (err)
212 return err;
213
214 flow_key->mpls.lse[0] = lse;
215 return 0;
216}
217
218static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
219{
220 int err;
221
222 err = skb_vlan_pop(skb);
223 if (skb_vlan_tag_present(skb)) {
224 invalidate_flow_key(key);
225 } else {
226 key->eth.vlan.tci = 0;
227 key->eth.vlan.tpid = 0;
228 }
229 return err;
230}
231
232static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
233 const struct ovs_action_push_vlan *vlan)
234{
235 if (skb_vlan_tag_present(skb)) {
236 invalidate_flow_key(key);
237 } else {
238 key->eth.vlan.tci = vlan->vlan_tci;
239 key->eth.vlan.tpid = vlan->vlan_tpid;
240 }
241 return skb_vlan_push(skb, vlan_proto: vlan->vlan_tpid,
242 ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK);
243}
244
245/* 'src' is already properly masked. */
246static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
247{
248 u16 *dst = (u16 *)dst_;
249 const u16 *src = (const u16 *)src_;
250 const u16 *mask = (const u16 *)mask_;
251
252 OVS_SET_MASKED(dst[0], src[0], mask[0]);
253 OVS_SET_MASKED(dst[1], src[1], mask[1]);
254 OVS_SET_MASKED(dst[2], src[2], mask[2]);
255}
256
257static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
258 const struct ovs_key_ethernet *key,
259 const struct ovs_key_ethernet *mask)
260{
261 int err;
262
263 err = skb_ensure_writable(skb, ETH_HLEN);
264 if (unlikely(err))
265 return err;
266
267 skb_postpull_rcsum(skb, start: eth_hdr(skb), ETH_ALEN * 2);
268
269 ether_addr_copy_masked(dst_: eth_hdr(skb)->h_source, src_: key->eth_src,
270 mask_: mask->eth_src);
271 ether_addr_copy_masked(dst_: eth_hdr(skb)->h_dest, src_: key->eth_dst,
272 mask_: mask->eth_dst);
273
274 skb_postpush_rcsum(skb, start: eth_hdr(skb), ETH_ALEN * 2);
275
276 ether_addr_copy(dst: flow_key->eth.src, src: eth_hdr(skb)->h_source);
277 ether_addr_copy(dst: flow_key->eth.dst, src: eth_hdr(skb)->h_dest);
278 return 0;
279}
280
281/* pop_eth does not support VLAN packets as this action is never called
282 * for them.
283 */
284static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
285{
286 int err;
287
288 err = skb_eth_pop(skb);
289 if (err)
290 return err;
291
292 /* safe right before invalidate_flow_key */
293 key->mac_proto = MAC_PROTO_NONE;
294 invalidate_flow_key(key);
295 return 0;
296}
297
298static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
299 const struct ovs_action_push_eth *ethh)
300{
301 int err;
302
303 err = skb_eth_push(skb, dst: ethh->addresses.eth_dst,
304 src: ethh->addresses.eth_src);
305 if (err)
306 return err;
307
308 /* safe right before invalidate_flow_key */
309 key->mac_proto = MAC_PROTO_ETHERNET;
310 invalidate_flow_key(key);
311 return 0;
312}
313
314static noinline_for_stack int push_nsh(struct sk_buff *skb,
315 struct sw_flow_key *key,
316 const struct nlattr *a)
317{
318 u8 buffer[NSH_HDR_MAX_LEN];
319 struct nshhdr *nh = (struct nshhdr *)buffer;
320 int err;
321
322 err = nsh_hdr_from_nlattr(attr: a, nh, NSH_HDR_MAX_LEN);
323 if (err)
324 return err;
325
326 err = nsh_push(skb, pushed_nh: nh);
327 if (err)
328 return err;
329
330 /* safe right before invalidate_flow_key */
331 key->mac_proto = MAC_PROTO_NONE;
332 invalidate_flow_key(key);
333 return 0;
334}
335
336static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key)
337{
338 int err;
339
340 err = nsh_pop(skb);
341 if (err)
342 return err;
343
344 /* safe right before invalidate_flow_key */
345 if (skb->protocol == htons(ETH_P_TEB))
346 key->mac_proto = MAC_PROTO_ETHERNET;
347 else
348 key->mac_proto = MAC_PROTO_NONE;
349 invalidate_flow_key(key);
350 return 0;
351}
352
353static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
354 __be32 addr, __be32 new_addr)
355{
356 int transport_len = skb->len - skb_transport_offset(skb);
357
358 if (nh->frag_off & htons(IP_OFFSET))
359 return;
360
361 if (nh->protocol == IPPROTO_TCP) {
362 if (likely(transport_len >= sizeof(struct tcphdr)))
363 inet_proto_csum_replace4(sum: &tcp_hdr(skb)->check, skb,
364 from: addr, to: new_addr, pseudohdr: true);
365 } else if (nh->protocol == IPPROTO_UDP) {
366 if (likely(transport_len >= sizeof(struct udphdr))) {
367 struct udphdr *uh = udp_hdr(skb);
368
369 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
370 inet_proto_csum_replace4(sum: &uh->check, skb,
371 from: addr, to: new_addr, pseudohdr: true);
372 if (!uh->check)
373 uh->check = CSUM_MANGLED_0;
374 }
375 }
376 }
377}
378
379static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
380 __be32 *addr, __be32 new_addr)
381{
382 update_ip_l4_checksum(skb, nh, addr: *addr, new_addr);
383 csum_replace4(sum: &nh->check, from: *addr, to: new_addr);
384 skb_clear_hash(skb);
385 ovs_ct_clear(skb, NULL);
386 *addr = new_addr;
387}
388
389static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
390 __be32 addr[4], const __be32 new_addr[4])
391{
392 int transport_len = skb->len - skb_transport_offset(skb);
393
394 if (l4_proto == NEXTHDR_TCP) {
395 if (likely(transport_len >= sizeof(struct tcphdr)))
396 inet_proto_csum_replace16(sum: &tcp_hdr(skb)->check, skb,
397 from: addr, to: new_addr, pseudohdr: true);
398 } else if (l4_proto == NEXTHDR_UDP) {
399 if (likely(transport_len >= sizeof(struct udphdr))) {
400 struct udphdr *uh = udp_hdr(skb);
401
402 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
403 inet_proto_csum_replace16(sum: &uh->check, skb,
404 from: addr, to: new_addr, pseudohdr: true);
405 if (!uh->check)
406 uh->check = CSUM_MANGLED_0;
407 }
408 }
409 } else if (l4_proto == NEXTHDR_ICMP) {
410 if (likely(transport_len >= sizeof(struct icmp6hdr)))
411 inet_proto_csum_replace16(sum: &icmp6_hdr(skb)->icmp6_cksum,
412 skb, from: addr, to: new_addr, pseudohdr: true);
413 }
414}
415
416static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
417 const __be32 mask[4], __be32 masked[4])
418{
419 masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
420 masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
421 masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
422 masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
423}
424
425static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
426 __be32 addr[4], const __be32 new_addr[4],
427 bool recalculate_csum)
428{
429 if (recalculate_csum)
430 update_ipv6_checksum(skb, l4_proto, addr, new_addr);
431
432 skb_clear_hash(skb);
433 ovs_ct_clear(skb, NULL);
434 memcpy(addr, new_addr, sizeof(__be32[4]));
435}
436
437static void set_ipv6_dsfield(struct sk_buff *skb, struct ipv6hdr *nh, u8 ipv6_tclass, u8 mask)
438{
439 u8 old_ipv6_tclass = ipv6_get_dsfield(ipv6h: nh);
440
441 ipv6_tclass = OVS_MASKED(old_ipv6_tclass, ipv6_tclass, mask);
442
443 if (skb->ip_summed == CHECKSUM_COMPLETE)
444 csum_replace(csum: &skb->csum, old: (__force __wsum)(old_ipv6_tclass << 12),
445 new: (__force __wsum)(ipv6_tclass << 12));
446
447 ipv6_change_dsfield(ipv6h: nh, mask: ~mask, value: ipv6_tclass);
448}
449
450static void set_ipv6_fl(struct sk_buff *skb, struct ipv6hdr *nh, u32 fl, u32 mask)
451{
452 u32 ofl;
453
454 ofl = nh->flow_lbl[0] << 16 | nh->flow_lbl[1] << 8 | nh->flow_lbl[2];
455 fl = OVS_MASKED(ofl, fl, mask);
456
457 /* Bits 21-24 are always unmasked, so this retains their values. */
458 nh->flow_lbl[0] = (u8)(fl >> 16);
459 nh->flow_lbl[1] = (u8)(fl >> 8);
460 nh->flow_lbl[2] = (u8)fl;
461
462 if (skb->ip_summed == CHECKSUM_COMPLETE)
463 csum_replace(csum: &skb->csum, old: (__force __wsum)htonl(ofl), new: (__force __wsum)htonl(fl));
464}
465
466static void set_ipv6_ttl(struct sk_buff *skb, struct ipv6hdr *nh, u8 new_ttl, u8 mask)
467{
468 new_ttl = OVS_MASKED(nh->hop_limit, new_ttl, mask);
469
470 if (skb->ip_summed == CHECKSUM_COMPLETE)
471 csum_replace(csum: &skb->csum, old: (__force __wsum)(nh->hop_limit << 8),
472 new: (__force __wsum)(new_ttl << 8));
473 nh->hop_limit = new_ttl;
474}
475
476static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
477 u8 mask)
478{
479 new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);
480
481 csum_replace2(sum: &nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
482 nh->ttl = new_ttl;
483}
484
485static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
486 const struct ovs_key_ipv4 *key,
487 const struct ovs_key_ipv4 *mask)
488{
489 struct iphdr *nh;
490 __be32 new_addr;
491 int err;
492
493 err = skb_ensure_writable(skb, write_len: skb_network_offset(skb) +
494 sizeof(struct iphdr));
495 if (unlikely(err))
496 return err;
497
498 nh = ip_hdr(skb);
499
500 /* Setting an IP addresses is typically only a side effect of
501 * matching on them in the current userspace implementation, so it
502 * makes sense to check if the value actually changed.
503 */
504 if (mask->ipv4_src) {
505 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
506
507 if (unlikely(new_addr != nh->saddr)) {
508 set_ip_addr(skb, nh, addr: &nh->saddr, new_addr);
509 flow_key->ipv4.addr.src = new_addr;
510 }
511 }
512 if (mask->ipv4_dst) {
513 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
514
515 if (unlikely(new_addr != nh->daddr)) {
516 set_ip_addr(skb, nh, addr: &nh->daddr, new_addr);
517 flow_key->ipv4.addr.dst = new_addr;
518 }
519 }
520 if (mask->ipv4_tos) {
521 ipv4_change_dsfield(iph: nh, mask: ~mask->ipv4_tos, value: key->ipv4_tos);
522 flow_key->ip.tos = nh->tos;
523 }
524 if (mask->ipv4_ttl) {
525 set_ip_ttl(skb, nh, new_ttl: key->ipv4_ttl, mask: mask->ipv4_ttl);
526 flow_key->ip.ttl = nh->ttl;
527 }
528
529 return 0;
530}
531
532static bool is_ipv6_mask_nonzero(const __be32 addr[4])
533{
534 return !!(addr[0] | addr[1] | addr[2] | addr[3]);
535}
536
537static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
538 const struct ovs_key_ipv6 *key,
539 const struct ovs_key_ipv6 *mask)
540{
541 struct ipv6hdr *nh;
542 int err;
543
544 err = skb_ensure_writable(skb, write_len: skb_network_offset(skb) +
545 sizeof(struct ipv6hdr));
546 if (unlikely(err))
547 return err;
548
549 nh = ipv6_hdr(skb);
550
551 /* Setting an IP addresses is typically only a side effect of
552 * matching on them in the current userspace implementation, so it
553 * makes sense to check if the value actually changed.
554 */
555 if (is_ipv6_mask_nonzero(addr: mask->ipv6_src)) {
556 __be32 *saddr = (__be32 *)&nh->saddr;
557 __be32 masked[4];
558
559 mask_ipv6_addr(old: saddr, addr: key->ipv6_src, mask: mask->ipv6_src, masked);
560
561 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
562 set_ipv6_addr(skb, l4_proto: flow_key->ip.proto, addr: saddr, new_addr: masked,
563 recalculate_csum: true);
564 memcpy(&flow_key->ipv6.addr.src, masked,
565 sizeof(flow_key->ipv6.addr.src));
566 }
567 }
568 if (is_ipv6_mask_nonzero(addr: mask->ipv6_dst)) {
569 unsigned int offset = 0;
570 int flags = IP6_FH_F_SKIP_RH;
571 bool recalc_csum = true;
572 __be32 *daddr = (__be32 *)&nh->daddr;
573 __be32 masked[4];
574
575 mask_ipv6_addr(old: daddr, addr: key->ipv6_dst, mask: mask->ipv6_dst, masked);
576
577 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
578 if (ipv6_ext_hdr(nexthdr: nh->nexthdr))
579 recalc_csum = (ipv6_find_hdr(skb, offset: &offset,
580 NEXTHDR_ROUTING,
581 NULL, fragflg: &flags)
582 != NEXTHDR_ROUTING);
583
584 set_ipv6_addr(skb, l4_proto: flow_key->ip.proto, addr: daddr, new_addr: masked,
585 recalculate_csum: recalc_csum);
586 memcpy(&flow_key->ipv6.addr.dst, masked,
587 sizeof(flow_key->ipv6.addr.dst));
588 }
589 }
590 if (mask->ipv6_tclass) {
591 set_ipv6_dsfield(skb, nh, ipv6_tclass: key->ipv6_tclass, mask: mask->ipv6_tclass);
592 flow_key->ip.tos = ipv6_get_dsfield(ipv6h: nh);
593 }
594 if (mask->ipv6_label) {
595 set_ipv6_fl(skb, nh, ntohl(key->ipv6_label),
596 ntohl(mask->ipv6_label));
597 flow_key->ipv6.label =
598 *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
599 }
600 if (mask->ipv6_hlimit) {
601 set_ipv6_ttl(skb, nh, new_ttl: key->ipv6_hlimit, mask: mask->ipv6_hlimit);
602 flow_key->ip.ttl = nh->hop_limit;
603 }
604 return 0;
605}
606
607static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key,
608 const struct nlattr *a)
609{
610 struct nshhdr *nh;
611 size_t length;
612 int err;
613 u8 flags;
614 u8 ttl;
615 int i;
616
617 struct ovs_key_nsh key;
618 struct ovs_key_nsh mask;
619
620 err = nsh_key_from_nlattr(attr: a, nsh: &key, nsh_mask: &mask);
621 if (err)
622 return err;
623
624 /* Make sure the NSH base header is there */
625 if (!pskb_may_pull(skb, len: skb_network_offset(skb) + NSH_BASE_HDR_LEN))
626 return -ENOMEM;
627
628 nh = nsh_hdr(skb);
629 length = nsh_hdr_len(nsh: nh);
630
631 /* Make sure the whole NSH header is there */
632 err = skb_ensure_writable(skb, write_len: skb_network_offset(skb) +
633 length);
634 if (unlikely(err))
635 return err;
636
637 nh = nsh_hdr(skb);
638 skb_postpull_rcsum(skb, start: nh, len: length);
639 flags = nsh_get_flags(nsh: nh);
640 flags = OVS_MASKED(flags, key.base.flags, mask.base.flags);
641 flow_key->nsh.base.flags = flags;
642 ttl = nsh_get_ttl(nsh: nh);
643 ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl);
644 flow_key->nsh.base.ttl = ttl;
645 nsh_set_flags_and_ttl(nsh: nh, flags, ttl);
646 nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr,
647 mask.base.path_hdr);
648 flow_key->nsh.base.path_hdr = nh->path_hdr;
649 switch (nh->mdtype) {
650 case NSH_M_TYPE1:
651 for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) {
652 nh->md1.context[i] =
653 OVS_MASKED(nh->md1.context[i], key.context[i],
654 mask.context[i]);
655 }
656 memcpy(flow_key->nsh.context, nh->md1.context,
657 sizeof(nh->md1.context));
658 break;
659 case NSH_M_TYPE2:
660 memset(flow_key->nsh.context, 0,
661 sizeof(flow_key->nsh.context));
662 break;
663 default:
664 return -EINVAL;
665 }
666 skb_postpush_rcsum(skb, start: nh, len: length);
667 return 0;
668}
669
670/* Must follow skb_ensure_writable() since that can move the skb data. */
671static void set_tp_port(struct sk_buff *skb, __be16 *port,
672 __be16 new_port, __sum16 *check)
673{
674 ovs_ct_clear(skb, NULL);
675 inet_proto_csum_replace2(sum: check, skb, from: *port, to: new_port, pseudohdr: false);
676 *port = new_port;
677}
678
679static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
680 const struct ovs_key_udp *key,
681 const struct ovs_key_udp *mask)
682{
683 struct udphdr *uh;
684 __be16 src, dst;
685 int err;
686
687 err = skb_ensure_writable(skb, write_len: skb_transport_offset(skb) +
688 sizeof(struct udphdr));
689 if (unlikely(err))
690 return err;
691
692 uh = udp_hdr(skb);
693 /* Either of the masks is non-zero, so do not bother checking them. */
694 src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
695 dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);
696
697 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
698 if (likely(src != uh->source)) {
699 set_tp_port(skb, port: &uh->source, new_port: src, check: &uh->check);
700 flow_key->tp.src = src;
701 }
702 if (likely(dst != uh->dest)) {
703 set_tp_port(skb, port: &uh->dest, new_port: dst, check: &uh->check);
704 flow_key->tp.dst = dst;
705 }
706
707 if (unlikely(!uh->check))
708 uh->check = CSUM_MANGLED_0;
709 } else {
710 uh->source = src;
711 uh->dest = dst;
712 flow_key->tp.src = src;
713 flow_key->tp.dst = dst;
714 ovs_ct_clear(skb, NULL);
715 }
716
717 skb_clear_hash(skb);
718
719 return 0;
720}
721
722static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
723 const struct ovs_key_tcp *key,
724 const struct ovs_key_tcp *mask)
725{
726 struct tcphdr *th;
727 __be16 src, dst;
728 int err;
729
730 err = skb_ensure_writable(skb, write_len: skb_transport_offset(skb) +
731 sizeof(struct tcphdr));
732 if (unlikely(err))
733 return err;
734
735 th = tcp_hdr(skb);
736 src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
737 if (likely(src != th->source)) {
738 set_tp_port(skb, port: &th->source, new_port: src, check: &th->check);
739 flow_key->tp.src = src;
740 }
741 dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
742 if (likely(dst != th->dest)) {
743 set_tp_port(skb, port: &th->dest, new_port: dst, check: &th->check);
744 flow_key->tp.dst = dst;
745 }
746 skb_clear_hash(skb);
747
748 return 0;
749}
750
751static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
752 const struct ovs_key_sctp *key,
753 const struct ovs_key_sctp *mask)
754{
755 unsigned int sctphoff = skb_transport_offset(skb);
756 struct sctphdr *sh;
757 __le32 old_correct_csum, new_csum, old_csum;
758 int err;
759
760 err = skb_ensure_writable(skb, write_len: sctphoff + sizeof(struct sctphdr));
761 if (unlikely(err))
762 return err;
763
764 sh = sctp_hdr(skb);
765 old_csum = sh->checksum;
766 old_correct_csum = sctp_compute_cksum(skb, offset: sctphoff);
767
768 sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
769 sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
770
771 new_csum = sctp_compute_cksum(skb, offset: sctphoff);
772
773 /* Carry any checksum errors through. */
774 sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
775
776 skb_clear_hash(skb);
777 ovs_ct_clear(skb, NULL);
778
779 flow_key->tp.src = sh->source;
780 flow_key->tp.dst = sh->dest;
781
782 return 0;
783}
784
785static int ovs_vport_output(struct net *net, struct sock *sk,
786 struct sk_buff *skb)
787{
788 struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
789 struct vport *vport = data->vport;
790
791 if (skb_cow_head(skb, headroom: data->l2_len) < 0) {
792 kfree_skb_reason(skb, reason: SKB_DROP_REASON_NOMEM);
793 return -ENOMEM;
794 }
795
796 __skb_dst_copy(nskb: skb, refdst: data->dst);
797 *OVS_CB(skb) = data->cb;
798 skb->inner_protocol = data->inner_protocol;
799 if (data->vlan_tci & VLAN_CFI_MASK)
800 __vlan_hwaccel_put_tag(skb, vlan_proto: data->vlan_proto, vlan_tci: data->vlan_tci & ~VLAN_CFI_MASK);
801 else
802 __vlan_hwaccel_clear_tag(skb);
803
804 /* Reconstruct the MAC header. */
805 skb_push(skb, len: data->l2_len);
806 memcpy(skb->data, &data->l2_data, data->l2_len);
807 skb_postpush_rcsum(skb, start: skb->data, len: data->l2_len);
808 skb_reset_mac_header(skb);
809
810 if (eth_p_mpls(eth_type: skb->protocol)) {
811 skb->inner_network_header = skb->network_header;
812 skb_set_network_header(skb, offset: data->network_offset);
813 skb_reset_mac_len(skb);
814 }
815
816 ovs_vport_send(vport, skb, mac_proto: data->mac_proto);
817 return 0;
818}
819
820static unsigned int
821ovs_dst_get_mtu(const struct dst_entry *dst)
822{
823 return dst->dev->mtu;
824}
825
826static struct dst_ops ovs_dst_ops = {
827 .family = AF_UNSPEC,
828 .mtu = ovs_dst_get_mtu,
829};
830
831/* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
832 * ovs_vport_output(), which is called once per fragmented packet.
833 */
834static void prepare_frag(struct vport *vport, struct sk_buff *skb,
835 u16 orig_network_offset, u8 mac_proto)
836{
837 unsigned int hlen = skb_network_offset(skb);
838 struct ovs_frag_data *data;
839
840 data = this_cpu_ptr(&ovs_frag_data_storage);
841 data->dst = skb->_skb_refdst;
842 data->vport = vport;
843 data->cb = *OVS_CB(skb);
844 data->inner_protocol = skb->inner_protocol;
845 data->network_offset = orig_network_offset;
846 if (skb_vlan_tag_present(skb))
847 data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK;
848 else
849 data->vlan_tci = 0;
850 data->vlan_proto = skb->vlan_proto;
851 data->mac_proto = mac_proto;
852 data->l2_len = hlen;
853 memcpy(&data->l2_data, skb->data, hlen);
854
855 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
856 skb_pull(skb, len: hlen);
857}
858
859static void ovs_fragment(struct net *net, struct vport *vport,
860 struct sk_buff *skb, u16 mru,
861 struct sw_flow_key *key)
862{
863 enum ovs_drop_reason reason;
864 u16 orig_network_offset = 0;
865
866 if (eth_p_mpls(eth_type: skb->protocol)) {
867 orig_network_offset = skb_network_offset(skb);
868 skb->network_header = skb->inner_network_header;
869 }
870
871 if (skb_network_offset(skb) > MAX_L2_LEN) {
872 OVS_NLERR(1, "L2 header too long to fragment");
873 reason = OVS_DROP_FRAG_L2_TOO_LONG;
874 goto err;
875 }
876
877 if (key->eth.type == htons(ETH_P_IP)) {
878 struct rtable ovs_rt = { 0 };
879 unsigned long orig_dst;
880
881 prepare_frag(vport, skb, orig_network_offset,
882 mac_proto: ovs_key_mac_proto(key));
883 dst_init(dst: &ovs_rt.dst, ops: &ovs_dst_ops, NULL,
884 DST_OBSOLETE_NONE, DST_NOCOUNT);
885 ovs_rt.dst.dev = vport->dev;
886
887 orig_dst = skb->_skb_refdst;
888 skb_dst_set_noref(skb, dst: &ovs_rt.dst);
889 IPCB(skb)->frag_max_size = mru;
890
891 ip_do_fragment(net, sk: skb->sk, skb, output: ovs_vport_output);
892 refdst_drop(refdst: orig_dst);
893 } else if (key->eth.type == htons(ETH_P_IPV6)) {
894 unsigned long orig_dst;
895 struct rt6_info ovs_rt;
896
897 prepare_frag(vport, skb, orig_network_offset,
898 mac_proto: ovs_key_mac_proto(key));
899 memset(&ovs_rt, 0, sizeof(ovs_rt));
900 dst_init(dst: &ovs_rt.dst, ops: &ovs_dst_ops, NULL,
901 DST_OBSOLETE_NONE, DST_NOCOUNT);
902 ovs_rt.dst.dev = vport->dev;
903
904 orig_dst = skb->_skb_refdst;
905 skb_dst_set_noref(skb, dst: &ovs_rt.dst);
906 IP6CB(skb)->frag_max_size = mru;
907
908 ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output);
909 refdst_drop(refdst: orig_dst);
910 } else {
911 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
912 ovs_vport_name(vport), ntohs(key->eth.type), mru,
913 vport->dev->mtu);
914 reason = OVS_DROP_FRAG_INVALID_PROTO;
915 goto err;
916 }
917
918 return;
919err:
920 ovs_kfree_skb_reason(skb, reason);
921}
922
923static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
924 struct sw_flow_key *key)
925{
926 struct vport *vport = ovs_vport_rcu(dp, port_no: out_port);
927
928 if (likely(vport && netif_carrier_ok(vport->dev))) {
929 u16 mru = OVS_CB(skb)->mru;
930 u32 cutlen = OVS_CB(skb)->cutlen;
931
932 if (unlikely(cutlen > 0)) {
933 if (skb->len - cutlen > ovs_mac_header_len(key))
934 pskb_trim(skb, len: skb->len - cutlen);
935 else
936 pskb_trim(skb, len: ovs_mac_header_len(key));
937 }
938
939 if (likely(!mru ||
940 (skb->len <= mru + vport->dev->hard_header_len))) {
941 ovs_vport_send(vport, skb, mac_proto: ovs_key_mac_proto(key));
942 } else if (mru <= vport->dev->mtu) {
943 struct net *net = read_pnet(pnet: &dp->net);
944
945 ovs_fragment(net, vport, skb, mru, key);
946 } else {
947 kfree_skb_reason(skb, reason: SKB_DROP_REASON_PKT_TOO_BIG);
948 }
949 } else {
950 kfree_skb_reason(skb, reason: SKB_DROP_REASON_DEV_READY);
951 }
952}
953
954static int output_userspace(struct datapath *dp, struct sk_buff *skb,
955 struct sw_flow_key *key, const struct nlattr *attr,
956 const struct nlattr *actions, int actions_len,
957 uint32_t cutlen)
958{
959 struct dp_upcall_info upcall;
960 const struct nlattr *a;
961 int rem;
962
963 memset(&upcall, 0, sizeof(upcall));
964 upcall.cmd = OVS_PACKET_CMD_ACTION;
965 upcall.mru = OVS_CB(skb)->mru;
966
967 for (a = nla_data(nla: attr), rem = nla_len(nla: attr); rem > 0;
968 a = nla_next(nla: a, remaining: &rem)) {
969 switch (nla_type(nla: a)) {
970 case OVS_USERSPACE_ATTR_USERDATA:
971 upcall.userdata = a;
972 break;
973
974 case OVS_USERSPACE_ATTR_PID:
975 if (dp->user_features &
976 OVS_DP_F_DISPATCH_UPCALL_PER_CPU)
977 upcall.portid =
978 ovs_dp_get_upcall_portid(dp,
979 smp_processor_id());
980 else
981 upcall.portid = nla_get_u32(nla: a);
982 break;
983
984 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
985 /* Get out tunnel info. */
986 struct vport *vport;
987
988 vport = ovs_vport_rcu(dp, port_no: nla_get_u32(nla: a));
989 if (vport) {
990 int err;
991
992 err = dev_fill_metadata_dst(dev: vport->dev, skb);
993 if (!err)
994 upcall.egress_tun_info = skb_tunnel_info(skb);
995 }
996
997 break;
998 }
999
1000 case OVS_USERSPACE_ATTR_ACTIONS: {
1001 /* Include actions. */
1002 upcall.actions = actions;
1003 upcall.actions_len = actions_len;
1004 break;
1005 }
1006
1007 } /* End of switch. */
1008 }
1009
1010 return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
1011}
1012
1013static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb,
1014 struct sw_flow_key *key,
1015 const struct nlattr *attr)
1016{
1017 /* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */
1018 struct nlattr *actions = nla_data(nla: attr);
1019
1020 if (nla_len(nla: actions))
1021 return clone_execute(dp, skb, key, recirc_id: 0, actions: nla_data(nla: actions),
1022 len: nla_len(nla: actions), last: true, clone_flow_key: false);
1023
1024 ovs_kfree_skb_reason(skb, reason: OVS_DROP_IP_TTL);
1025 return 0;
1026}
1027
1028/* When 'last' is true, sample() should always consume the 'skb'.
1029 * Otherwise, sample() should keep 'skb' intact regardless what
1030 * actions are executed within sample().
1031 */
1032static int sample(struct datapath *dp, struct sk_buff *skb,
1033 struct sw_flow_key *key, const struct nlattr *attr,
1034 bool last)
1035{
1036 struct nlattr *actions;
1037 struct nlattr *sample_arg;
1038 int rem = nla_len(nla: attr);
1039 const struct sample_arg *arg;
1040 bool clone_flow_key;
1041
1042 /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */
1043 sample_arg = nla_data(nla: attr);
1044 arg = nla_data(nla: sample_arg);
1045 actions = nla_next(nla: sample_arg, remaining: &rem);
1046
1047 if ((arg->probability != U32_MAX) &&
1048 (!arg->probability || get_random_u32() > arg->probability)) {
1049 if (last)
1050 ovs_kfree_skb_reason(skb, reason: OVS_DROP_LAST_ACTION);
1051 return 0;
1052 }
1053
1054 clone_flow_key = !arg->exec;
1055 return clone_execute(dp, skb, key, recirc_id: 0, actions, len: rem, last,
1056 clone_flow_key);
1057}
1058
1059/* When 'last' is true, clone() should always consume the 'skb'.
1060 * Otherwise, clone() should keep 'skb' intact regardless what
1061 * actions are executed within clone().
1062 */
1063static int clone(struct datapath *dp, struct sk_buff *skb,
1064 struct sw_flow_key *key, const struct nlattr *attr,
1065 bool last)
1066{
1067 struct nlattr *actions;
1068 struct nlattr *clone_arg;
1069 int rem = nla_len(nla: attr);
1070 bool dont_clone_flow_key;
1071
1072 /* The first action is always 'OVS_CLONE_ATTR_EXEC'. */
1073 clone_arg = nla_data(nla: attr);
1074 dont_clone_flow_key = nla_get_u32(nla: clone_arg);
1075 actions = nla_next(nla: clone_arg, remaining: &rem);
1076
1077 return clone_execute(dp, skb, key, recirc_id: 0, actions, len: rem, last,
1078 clone_flow_key: !dont_clone_flow_key);
1079}
1080
1081static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
1082 const struct nlattr *attr)
1083{
1084 struct ovs_action_hash *hash_act = nla_data(nla: attr);
1085 u32 hash = 0;
1086
1087 if (hash_act->hash_alg == OVS_HASH_ALG_L4) {
1088 /* OVS_HASH_ALG_L4 hasing type. */
1089 hash = skb_get_hash(skb);
1090 } else if (hash_act->hash_alg == OVS_HASH_ALG_SYM_L4) {
1091 /* OVS_HASH_ALG_SYM_L4 hashing type. NOTE: this doesn't
1092 * extend past an encapsulated header.
1093 */
1094 hash = __skb_get_hash_symmetric(skb);
1095 }
1096
1097 hash = jhash_1word(a: hash, initval: hash_act->hash_basis);
1098 if (!hash)
1099 hash = 0x1;
1100
1101 key->ovs_flow_hash = hash;
1102}
1103
1104static int execute_set_action(struct sk_buff *skb,
1105 struct sw_flow_key *flow_key,
1106 const struct nlattr *a)
1107{
1108 /* Only tunnel set execution is supported without a mask. */
1109 if (nla_type(nla: a) == OVS_KEY_ATTR_TUNNEL_INFO) {
1110 struct ovs_tunnel_info *tun = nla_data(nla: a);
1111
1112 skb_dst_drop(skb);
1113 dst_hold(dst: (struct dst_entry *)tun->tun_dst);
1114 skb_dst_set(skb, dst: (struct dst_entry *)tun->tun_dst);
1115 return 0;
1116 }
1117
1118 return -EINVAL;
1119}
1120
1121/* Mask is at the midpoint of the data. */
1122#define get_mask(a, type) ((const type)nla_data(a) + 1)
1123
1124static int execute_masked_set_action(struct sk_buff *skb,
1125 struct sw_flow_key *flow_key,
1126 const struct nlattr *a)
1127{
1128 int err = 0;
1129
1130 switch (nla_type(nla: a)) {
1131 case OVS_KEY_ATTR_PRIORITY:
1132 OVS_SET_MASKED(skb->priority, nla_get_u32(a),
1133 *get_mask(a, u32 *));
1134 flow_key->phy.priority = skb->priority;
1135 break;
1136
1137 case OVS_KEY_ATTR_SKB_MARK:
1138 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
1139 flow_key->phy.skb_mark = skb->mark;
1140 break;
1141
1142 case OVS_KEY_ATTR_TUNNEL_INFO:
1143 /* Masked data not supported for tunnel. */
1144 err = -EINVAL;
1145 break;
1146
1147 case OVS_KEY_ATTR_ETHERNET:
1148 err = set_eth_addr(skb, flow_key, key: nla_data(nla: a),
1149 get_mask(a, struct ovs_key_ethernet *));
1150 break;
1151
1152 case OVS_KEY_ATTR_NSH:
1153 err = set_nsh(skb, flow_key, a);
1154 break;
1155
1156 case OVS_KEY_ATTR_IPV4:
1157 err = set_ipv4(skb, flow_key, key: nla_data(nla: a),
1158 get_mask(a, struct ovs_key_ipv4 *));
1159 break;
1160
1161 case OVS_KEY_ATTR_IPV6:
1162 err = set_ipv6(skb, flow_key, key: nla_data(nla: a),
1163 get_mask(a, struct ovs_key_ipv6 *));
1164 break;
1165
1166 case OVS_KEY_ATTR_TCP:
1167 err = set_tcp(skb, flow_key, key: nla_data(nla: a),
1168 get_mask(a, struct ovs_key_tcp *));
1169 break;
1170
1171 case OVS_KEY_ATTR_UDP:
1172 err = set_udp(skb, flow_key, key: nla_data(nla: a),
1173 get_mask(a, struct ovs_key_udp *));
1174 break;
1175
1176 case OVS_KEY_ATTR_SCTP:
1177 err = set_sctp(skb, flow_key, key: nla_data(nla: a),
1178 get_mask(a, struct ovs_key_sctp *));
1179 break;
1180
1181 case OVS_KEY_ATTR_MPLS:
1182 err = set_mpls(skb, flow_key, mpls_lse: nla_data(nla: a), get_mask(a,
1183 __be32 *));
1184 break;
1185
1186 case OVS_KEY_ATTR_CT_STATE:
1187 case OVS_KEY_ATTR_CT_ZONE:
1188 case OVS_KEY_ATTR_CT_MARK:
1189 case OVS_KEY_ATTR_CT_LABELS:
1190 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4:
1191 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6:
1192 err = -EINVAL;
1193 break;
1194 }
1195
1196 return err;
1197}
1198
1199static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
1200 struct sw_flow_key *key,
1201 const struct nlattr *a, bool last)
1202{
1203 u32 recirc_id;
1204
1205 if (!is_flow_key_valid(key)) {
1206 int err;
1207
1208 err = ovs_flow_key_update(skb, key);
1209 if (err)
1210 return err;
1211 }
1212 BUG_ON(!is_flow_key_valid(key));
1213
1214 recirc_id = nla_get_u32(nla: a);
1215 return clone_execute(dp, skb, key, recirc_id, NULL, len: 0, last, clone_flow_key: true);
1216}
1217
1218static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb,
1219 struct sw_flow_key *key,
1220 const struct nlattr *attr, bool last)
1221{
1222 struct ovs_skb_cb *ovs_cb = OVS_CB(skb);
1223 const struct nlattr *actions, *cpl_arg;
1224 int len, max_len, rem = nla_len(nla: attr);
1225 const struct check_pkt_len_arg *arg;
1226 bool clone_flow_key;
1227
1228 /* The first netlink attribute in 'attr' is always
1229 * 'OVS_CHECK_PKT_LEN_ATTR_ARG'.
1230 */
1231 cpl_arg = nla_data(nla: attr);
1232 arg = nla_data(nla: cpl_arg);
1233
1234 len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len;
1235 max_len = arg->pkt_len;
1236
1237 if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, len: max_len)) ||
1238 len <= max_len) {
1239 /* Second netlink attribute in 'attr' is always
1240 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'.
1241 */
1242 actions = nla_next(nla: cpl_arg, remaining: &rem);
1243 clone_flow_key = !arg->exec_for_lesser_equal;
1244 } else {
1245 /* Third netlink attribute in 'attr' is always
1246 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'.
1247 */
1248 actions = nla_next(nla: cpl_arg, remaining: &rem);
1249 actions = nla_next(nla: actions, remaining: &rem);
1250 clone_flow_key = !arg->exec_for_greater;
1251 }
1252
1253 return clone_execute(dp, skb, key, recirc_id: 0, actions: nla_data(nla: actions),
1254 len: nla_len(nla: actions), last, clone_flow_key);
1255}
1256
1257static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key)
1258{
1259 int err;
1260
1261 if (skb->protocol == htons(ETH_P_IPV6)) {
1262 struct ipv6hdr *nh;
1263
1264 err = skb_ensure_writable(skb, write_len: skb_network_offset(skb) +
1265 sizeof(*nh));
1266 if (unlikely(err))
1267 return err;
1268
1269 nh = ipv6_hdr(skb);
1270
1271 if (nh->hop_limit <= 1)
1272 return -EHOSTUNREACH;
1273
1274 key->ip.ttl = --nh->hop_limit;
1275 } else if (skb->protocol == htons(ETH_P_IP)) {
1276 struct iphdr *nh;
1277 u8 old_ttl;
1278
1279 err = skb_ensure_writable(skb, write_len: skb_network_offset(skb) +
1280 sizeof(*nh));
1281 if (unlikely(err))
1282 return err;
1283
1284 nh = ip_hdr(skb);
1285 if (nh->ttl <= 1)
1286 return -EHOSTUNREACH;
1287
1288 old_ttl = nh->ttl--;
1289 csum_replace2(sum: &nh->check, htons(old_ttl << 8),
1290 htons(nh->ttl << 8));
1291 key->ip.ttl = nh->ttl;
1292 }
1293 return 0;
1294}
1295
1296/* Execute a list of actions against 'skb'. */
1297static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
1298 struct sw_flow_key *key,
1299 const struct nlattr *attr, int len)
1300{
1301 const struct nlattr *a;
1302 int rem;
1303
1304 for (a = attr, rem = len; rem > 0;
1305 a = nla_next(nla: a, remaining: &rem)) {
1306 int err = 0;
1307
1308 if (trace_ovs_do_execute_action_enabled())
1309 trace_ovs_do_execute_action(dp, skb, key, a, rem);
1310
1311 /* Actions that rightfully have to consume the skb should do it
1312 * and return directly.
1313 */
1314 switch (nla_type(nla: a)) {
1315 case OVS_ACTION_ATTR_OUTPUT: {
1316 int port = nla_get_u32(nla: a);
1317 struct sk_buff *clone;
1318
1319 /* Every output action needs a separate clone
1320 * of 'skb', In case the output action is the
1321 * last action, cloning can be avoided.
1322 */
1323 if (nla_is_last(nla: a, rem)) {
1324 do_output(dp, skb, out_port: port, key);
1325 /* 'skb' has been used for output.
1326 */
1327 return 0;
1328 }
1329
1330 clone = skb_clone(skb, GFP_ATOMIC);
1331 if (clone)
1332 do_output(dp, skb: clone, out_port: port, key);
1333 OVS_CB(skb)->cutlen = 0;
1334 break;
1335 }
1336
1337 case OVS_ACTION_ATTR_TRUNC: {
1338 struct ovs_action_trunc *trunc = nla_data(nla: a);
1339
1340 if (skb->len > trunc->max_len)
1341 OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
1342 break;
1343 }
1344
1345 case OVS_ACTION_ATTR_USERSPACE:
1346 output_userspace(dp, skb, key, attr: a, actions: attr,
1347 actions_len: len, OVS_CB(skb)->cutlen);
1348 OVS_CB(skb)->cutlen = 0;
1349 if (nla_is_last(nla: a, rem)) {
1350 consume_skb(skb);
1351 return 0;
1352 }
1353 break;
1354
1355 case OVS_ACTION_ATTR_HASH:
1356 execute_hash(skb, key, attr: a);
1357 break;
1358
1359 case OVS_ACTION_ATTR_PUSH_MPLS: {
1360 struct ovs_action_push_mpls *mpls = nla_data(nla: a);
1361
1362 err = push_mpls(skb, key, mpls_lse: mpls->mpls_lse,
1363 mpls_ethertype: mpls->mpls_ethertype, mac_len: skb->mac_len);
1364 break;
1365 }
1366 case OVS_ACTION_ATTR_ADD_MPLS: {
1367 struct ovs_action_add_mpls *mpls = nla_data(nla: a);
1368 __u16 mac_len = 0;
1369
1370 if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK)
1371 mac_len = skb->mac_len;
1372
1373 err = push_mpls(skb, key, mpls_lse: mpls->mpls_lse,
1374 mpls_ethertype: mpls->mpls_ethertype, mac_len);
1375 break;
1376 }
1377 case OVS_ACTION_ATTR_POP_MPLS:
1378 err = pop_mpls(skb, key, ethertype: nla_get_be16(nla: a));
1379 break;
1380
1381 case OVS_ACTION_ATTR_PUSH_VLAN:
1382 err = push_vlan(skb, key, vlan: nla_data(nla: a));
1383 break;
1384
1385 case OVS_ACTION_ATTR_POP_VLAN:
1386 err = pop_vlan(skb, key);
1387 break;
1388
1389 case OVS_ACTION_ATTR_RECIRC: {
1390 bool last = nla_is_last(nla: a, rem);
1391
1392 err = execute_recirc(dp, skb, key, a, last);
1393 if (last) {
1394 /* If this is the last action, the skb has
1395 * been consumed or freed.
1396 * Return immediately.
1397 */
1398 return err;
1399 }
1400 break;
1401 }
1402
1403 case OVS_ACTION_ATTR_SET:
1404 err = execute_set_action(skb, flow_key: key, a: nla_data(nla: a));
1405 break;
1406
1407 case OVS_ACTION_ATTR_SET_MASKED:
1408 case OVS_ACTION_ATTR_SET_TO_MASKED:
1409 err = execute_masked_set_action(skb, flow_key: key, a: nla_data(nla: a));
1410 break;
1411
1412 case OVS_ACTION_ATTR_SAMPLE: {
1413 bool last = nla_is_last(nla: a, rem);
1414
1415 err = sample(dp, skb, key, attr: a, last);
1416 if (last)
1417 return err;
1418
1419 break;
1420 }
1421
1422 case OVS_ACTION_ATTR_CT:
1423 if (!is_flow_key_valid(key)) {
1424 err = ovs_flow_key_update(skb, key);
1425 if (err)
1426 return err;
1427 }
1428
1429 err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
1430 nla_data(nla: a));
1431
1432 /* Hide stolen IP fragments from user space. */
1433 if (err)
1434 return err == -EINPROGRESS ? 0 : err;
1435 break;
1436
1437 case OVS_ACTION_ATTR_CT_CLEAR:
1438 err = ovs_ct_clear(skb, key);
1439 break;
1440
1441 case OVS_ACTION_ATTR_PUSH_ETH:
1442 err = push_eth(skb, key, ethh: nla_data(nla: a));
1443 break;
1444
1445 case OVS_ACTION_ATTR_POP_ETH:
1446 err = pop_eth(skb, key);
1447 break;
1448
1449 case OVS_ACTION_ATTR_PUSH_NSH:
1450 err = push_nsh(skb, key, a: nla_data(nla: a));
1451 break;
1452
1453 case OVS_ACTION_ATTR_POP_NSH:
1454 err = pop_nsh(skb, key);
1455 break;
1456
1457 case OVS_ACTION_ATTR_METER:
1458 if (ovs_meter_execute(dp, skb, key, meter_id: nla_get_u32(nla: a))) {
1459 ovs_kfree_skb_reason(skb, reason: OVS_DROP_METER);
1460 return 0;
1461 }
1462 break;
1463
1464 case OVS_ACTION_ATTR_CLONE: {
1465 bool last = nla_is_last(nla: a, rem);
1466
1467 err = clone(dp, skb, key, attr: a, last);
1468 if (last)
1469 return err;
1470
1471 break;
1472 }
1473
1474 case OVS_ACTION_ATTR_CHECK_PKT_LEN: {
1475 bool last = nla_is_last(nla: a, rem);
1476
1477 err = execute_check_pkt_len(dp, skb, key, attr: a, last);
1478 if (last)
1479 return err;
1480
1481 break;
1482 }
1483
1484 case OVS_ACTION_ATTR_DEC_TTL:
1485 err = execute_dec_ttl(skb, key);
1486 if (err == -EHOSTUNREACH)
1487 return dec_ttl_exception_handler(dp, skb,
1488 key, attr: a);
1489 break;
1490
1491 case OVS_ACTION_ATTR_DROP: {
1492 enum ovs_drop_reason reason = nla_get_u32(nla: a)
1493 ? OVS_DROP_EXPLICIT_WITH_ERROR
1494 : OVS_DROP_EXPLICIT;
1495
1496 ovs_kfree_skb_reason(skb, reason);
1497 return 0;
1498 }
1499 }
1500
1501 if (unlikely(err)) {
1502 ovs_kfree_skb_reason(skb, reason: OVS_DROP_ACTION_ERROR);
1503 return err;
1504 }
1505 }
1506
1507 ovs_kfree_skb_reason(skb, reason: OVS_DROP_LAST_ACTION);
1508 return 0;
1509}
1510
1511/* Execute the actions on the clone of the packet. The effect of the
1512 * execution does not affect the original 'skb' nor the original 'key'.
1513 *
1514 * The execution may be deferred in case the actions can not be executed
1515 * immediately.
1516 */
1517static int clone_execute(struct datapath *dp, struct sk_buff *skb,
1518 struct sw_flow_key *key, u32 recirc_id,
1519 const struct nlattr *actions, int len,
1520 bool last, bool clone_flow_key)
1521{
1522 struct deferred_action *da;
1523 struct sw_flow_key *clone;
1524
1525 skb = last ? skb : skb_clone(skb, GFP_ATOMIC);
1526 if (!skb) {
1527 /* Out of memory, skip this action.
1528 */
1529 return 0;
1530 }
1531
1532 /* When clone_flow_key is false, the 'key' will not be change
1533 * by the actions, then the 'key' can be used directly.
1534 * Otherwise, try to clone key from the next recursion level of
1535 * 'flow_keys'. If clone is successful, execute the actions
1536 * without deferring.
1537 */
1538 clone = clone_flow_key ? clone_key(key_: key) : key;
1539 if (clone) {
1540 int err = 0;
1541
1542 if (actions) { /* Sample action */
1543 if (clone_flow_key)
1544 __this_cpu_inc(exec_actions_level);
1545
1546 err = do_execute_actions(dp, skb, key: clone,
1547 attr: actions, len);
1548
1549 if (clone_flow_key)
1550 __this_cpu_dec(exec_actions_level);
1551 } else { /* Recirc action */
1552 clone->recirc_id = recirc_id;
1553 ovs_dp_process_packet(skb, key: clone);
1554 }
1555 return err;
1556 }
1557
1558 /* Out of 'flow_keys' space. Defer actions */
1559 da = add_deferred_actions(skb, key, actions, actions_len: len);
1560 if (da) {
1561 if (!actions) { /* Recirc action */
1562 key = &da->pkt_key;
1563 key->recirc_id = recirc_id;
1564 }
1565 } else {
1566 /* Out of per CPU action FIFO space. Drop the 'skb' and
1567 * log an error.
1568 */
1569 ovs_kfree_skb_reason(skb, reason: OVS_DROP_DEFERRED_LIMIT);
1570
1571 if (net_ratelimit()) {
1572 if (actions) { /* Sample action */
1573 pr_warn("%s: deferred action limit reached, drop sample action\n",
1574 ovs_dp_name(dp));
1575 } else { /* Recirc action */
1576 pr_warn("%s: deferred action limit reached, drop recirc action (recirc_id=%#x)\n",
1577 ovs_dp_name(dp), recirc_id);
1578 }
1579 }
1580 }
1581 return 0;
1582}
1583
1584static void process_deferred_actions(struct datapath *dp)
1585{
1586 struct action_fifo *fifo = this_cpu_ptr(action_fifos);
1587
1588 /* Do not touch the FIFO in case there is no deferred actions. */
1589 if (action_fifo_is_empty(fifo))
1590 return;
1591
1592 /* Finishing executing all deferred actions. */
1593 do {
1594 struct deferred_action *da = action_fifo_get(fifo);
1595 struct sk_buff *skb = da->skb;
1596 struct sw_flow_key *key = &da->pkt_key;
1597 const struct nlattr *actions = da->actions;
1598 int actions_len = da->actions_len;
1599
1600 if (actions)
1601 do_execute_actions(dp, skb, key, attr: actions, len: actions_len);
1602 else
1603 ovs_dp_process_packet(skb, key);
1604 } while (!action_fifo_is_empty(fifo));
1605
1606 /* Reset FIFO for the next packet. */
1607 action_fifo_init(fifo);
1608}
1609
1610/* Execute a list of actions against 'skb'. */
1611int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
1612 const struct sw_flow_actions *acts,
1613 struct sw_flow_key *key)
1614{
1615 int err, level;
1616
1617 level = __this_cpu_inc_return(exec_actions_level);
1618 if (unlikely(level > OVS_RECURSION_LIMIT)) {
1619 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
1620 ovs_dp_name(dp));
1621 ovs_kfree_skb_reason(skb, reason: OVS_DROP_RECURSION_LIMIT);
1622 err = -ENETDOWN;
1623 goto out;
1624 }
1625
1626 OVS_CB(skb)->acts_origlen = acts->orig_len;
1627 err = do_execute_actions(dp, skb, key,
1628 attr: acts->actions, len: acts->actions_len);
1629
1630 if (level == 1)
1631 process_deferred_actions(dp);
1632
1633out:
1634 __this_cpu_dec(exec_actions_level);
1635 return err;
1636}
1637
1638int action_fifos_init(void)
1639{
1640 action_fifos = alloc_percpu(struct action_fifo);
1641 if (!action_fifos)
1642 return -ENOMEM;
1643
1644 flow_keys = alloc_percpu(struct action_flow_keys);
1645 if (!flow_keys) {
1646 free_percpu(pdata: action_fifos);
1647 return -ENOMEM;
1648 }
1649
1650 return 0;
1651}
1652
1653void action_fifos_exit(void)
1654{
1655 free_percpu(pdata: action_fifos);
1656 free_percpu(pdata: flow_keys);
1657}
1658

source code of linux/net/openvswitch/actions.c