summaryrefslogtreecommitdiff
path: root/net/openvswitch/actions.c
blob: 8074ea00d577ef905c0974521b17f1641ecb870b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2007-2017 Nicira, Inc.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/skbuff.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/openvswitch.h>
#include <linux/sctp.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/in6.h>
#include <linux/if_arp.h>
#include <linux/if_vlan.h>

#include <net/dst.h>
#include <net/gso.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/ip6_fib.h>
#include <net/checksum.h>
#include <net/dsfield.h>
#include <net/mpls.h>
#include <net/sctp/checksum.h>

#include "datapath.h"
#include "flow.h"
#include "conntrack.h"
#include "vport.h"
#include "flow_netlink.h"
#include "openvswitch_trace.h"

struct deferred_action {
	struct sk_buff *skb;
	const struct nlattr *actions;
	int actions_len;

	/* Store pkt_key clone when creating deferred action. */
	struct sw_flow_key pkt_key;
};

#define MAX_L2_LEN	(VLAN_ETH_HLEN + 3 * MPLS_HLEN)
struct ovs_frag_data {
	unsigned long dst;
	struct vport *vport;
	struct ovs_skb_cb cb;
	__be16 inner_protocol;
	u16 network_offset;	/* valid only for MPLS */
	u16 vlan_tci;
	__be16 vlan_proto;
	unsigned int l2_len;
	u8 mac_proto;
	u8 l2_data[MAX_L2_LEN];
};

static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);

#define DEFERRED_ACTION_FIFO_SIZE 10
#define OVS_RECURSION_LIMIT 5
#define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2)
struct action_fifo {
	int head;
	int tail;
	/* Deferred action fifo queue storage. */
	struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
};

struct action_flow_keys {
	struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
};

static struct action_fifo __percpu *action_fifos;
static struct action_flow_keys __percpu *flow_keys;
static DEFINE_PER_CPU(int, exec_actions_level);

/* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys'
 * space. Return NULL if out of key spaces.
 */
static struct sw_flow_key *clone_key(const struct sw_flow_key *key_)
{
	struct action_flow_keys *keys = this_cpu_ptr(flow_keys);
	int level = this_cpu_read(exec_actions_level);
	struct sw_flow_key *key = NULL;

	if (level <= OVS_DEFERRED_ACTION_THRESHOLD) {
		key = &keys->key[level - 1];
		*key = *key_;
	}

	return key;
}

static void action_fifo_init(struct action_fifo *fifo)
{
	fifo->head = 0;
	fifo->tail = 0;
}

static bool action_fifo_is_empty(const struct action_fifo *fifo)
{
	return (fifo->head == fifo->tail);
}

static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
{
	if (action_fifo_is_empty(fifo))
		return NULL;

	return &fifo->fifo[fifo->tail++];
}

static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
{
	if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
		return NULL;

	return &fifo->fifo[fifo->head++];
}

/* Return true if fifo is not full */
static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
				    const struct sw_flow_key *key,
				    const struct nlattr *actions,
				    const int actions_len)
{
	struct action_fifo *fifo;
	struct deferred_action *da;

	fifo = this_cpu_ptr(action_fifos);
	da = action_fifo_put(fifo);
	if (da) {
		da->skb = skb;
		da->actions = actions;
		da->actions_len = actions_len;
		da->pkt_key = *key;
	}

	return da;
}

static void invalidate_flow_key(struct sw_flow_key *key)
{
	key->mac_proto |= SW_FLOW_KEY_INVALID;
}

static bool is_flow_key_valid(const struct sw_flow_key *key)
{
	return !(key->mac_proto & SW_FLOW_KEY_INVALID);
}

static int clone_execute(struct datapath *dp, struct sk_buff *skb,
			 struct sw_flow_key *key,
			 u32 recirc_id,
			 const struct nlattr *actions, int len,
			 bool last, bool clone_flow_key);

static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
			      struct sw_flow_key *key,
			      const struct nlattr *attr, int len);

static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
		     __be32 mpls_lse, __be16 mpls_ethertype, __u16 mac_len)
{
	int err;

	err = skb_mpls_push(skb, mpls_lse, mpls_ethertype, mac_len, !!mac_len);
	if (err)
		return err;

	if (!mac_len)
		key->mac_proto = MAC_PROTO_NONE;

	invalidate_flow_key(key);
	return 0;
}

static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
		    const __be16 ethertype)
{
	int err;

	err = skb_mpls_pop(skb, ethertype, skb->mac_len,
			   ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET);
	if (err)
		return err;

	if (ethertype == htons(ETH_P_TEB))
		key->mac_proto = MAC_PROTO_ETHERNET;

	invalidate_flow_key(key);
	return 0;
}

static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
		    const __be32 *mpls_lse, const __be32 *mask)
{
	struct mpls_shim_hdr *stack;
	__be32 lse;
	int err;

	if (!pskb_may_pull(skb, skb_network_offset(skb) + MPLS_HLEN))
		return -ENOMEM;

	stack = mpls_hdr(skb);
	lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
	err = skb_mpls_update_lse(skb, lse);
	if (err)
		return err;

	flow_key->mpls.lse[0] = lse;
	return 0;
}

static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
{
	int err;

	err = skb_vlan_pop(skb);
	if (skb_vlan_tag_present(skb)) {
		invalidate_flow_key(key);
	} else {
		key->eth.vlan.tci = 0;
		key->eth.vlan.tpid = 0;
	}
	return err;
}

static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
		     const struct ovs_action_push_vlan *vlan)
{
	if (skb_vlan_tag_present(skb)) {
		invalidate_flow_key(key);
	} else {
		key->eth.vlan.tci = vlan->vlan_tci;
		key->eth.vlan.tpid = vlan->vlan_tpid;
	}
	return skb_vlan_push(skb, vlan->vlan_tpid,
			     ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK);
}

/* 'src' is already properly masked. */
static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
{
	u16 *dst = (u16 *)dst_;
	const u16 *src = (const u16 *)src_;
	const u16 *mask = (const u16 *)mask_;

	OVS_SET_MASKED(dst[0], src[0], mask[0]);
	OVS_SET_MASKED(dst[1], src[1], mask[1]);
	OVS_SET_MASKED(dst[2], src[2], mask[2]);
}

static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
			const struct ovs_key_ethernet *key,
			const struct ovs_key_ethernet *mask)
{
	int err;

	err = skb_ensure_writable(skb, ETH_HLEN);
	if (unlikely(err))
		return err;

	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);

	ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
			       mask->eth_src);
	ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
			       mask->eth_dst);

	skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);

	ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
	ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
	return 0;
}

/* pop_eth does not support VLAN packets as this action is never called
 * for them.
 */
static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
{
	int err;

	err = skb_eth_pop(skb);
	if (err)
		return err;

	/* safe right before invalidate_flow_key */
	key->mac_proto = MAC_PROTO_NONE;
	invalidate_flow_key(key);
	return 0;
}

static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
		    const struct ovs_action_push_eth *ethh)
{
	int err;

	err = skb_eth_push(skb, ethh->addresses.eth_dst,
			   ethh->addresses.eth_src);
	if (err)
		return err;

	/* safe right before invalidate_flow_key */
	key->mac_proto = MAC_PROTO_ETHERNET;
	invalidate_flow_key(key);
	return 0;
}

static int push_nsh(struct sk_buff *skb, struct sw_flow_key *key,
		    const struct nshhdr *nh)
{
	int err;

	err = nsh_push(skb, nh);
	if (err)
		return err;

	/* safe right before invalidate_flow_key */
	key->mac_proto = MAC_PROTO_NONE;
	invalidate_flow_key(key);
	return 0;
}

static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key)
{
	int err;

	err = nsh_pop(skb);
	if (err)
		return err;

	/* safe right before invalidate_flow_key */
	if (skb->protocol == htons(ETH_P_TEB))
		key->mac_proto = MAC_PROTO_ETHERNET;
	else
		key->mac_proto = MAC_PROTO_NONE;
	invalidate_flow_key(key);
	return 0;
}

static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
				  __be32 addr, __be32 new_addr)
{
	int transport_len = skb->len - skb_transport_offset(skb);

	if (nh->frag_off & htons(IP_OFFSET))
		return;

	if (nh->protocol == IPPROTO_TCP) {
		if (likely(transport_len >= sizeof(struct tcphdr)))
			inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
						 addr, new_addr, true);
	} else if (nh->protocol == IPPROTO_UDP) {
		if (likely(transport_len >= sizeof(struct udphdr))) {
			struct udphdr *uh = udp_hdr(skb);

			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
				inet_proto_csum_replace4(&uh->check, skb,
							 addr, new_addr, true);
				if (!uh->check)
					uh->check = CSUM_MANGLED_0;
			}
		}
	}
}

static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
			__be32 *addr, __be32 new_addr)
{
	update_ip_l4_checksum(skb, nh, *addr, new_addr);
	csum_replace4(&nh->check, *addr, new_addr);
	skb_clear_hash(skb);
	ovs_ct_clear(skb, NULL);
	*addr = new_addr;
}

static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
				 __be32 addr[4], const __be32 new_addr[4])
{
	int transport_len = skb->len - skb_transport_offset(skb);

	if (l4_proto == NEXTHDR_TCP) {
		if (likely(transport_len >= sizeof(struct tcphdr)))
			inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
						  addr, new_addr, true);
	} else if (l4_proto == NEXTHDR_UDP) {
		if (likely(transport_len >= sizeof(struct udphdr))) {
			struct udphdr *uh = udp_hdr(skb);

			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
				inet_proto_csum_replace16(&uh->check, skb,
							  addr, new_addr, true);
				if (!uh->check)
					uh->check = CSUM_MANGLED_0;
			}
		}
	} else if (l4_proto == NEXTHDR_ICMP) {
		if (likely(transport_len >= sizeof(struct icmp6hdr)))
			inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
						  skb, addr, new_addr, true);
	}
}

static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
			   const __be32 mask[4], __be32 masked[4])
{
	masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
	masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
	masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
	masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
}

static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
			  __be32 addr[4], const __be32 new_addr[4],
			  bool recalculate_csum)
{
	if (recalculate_csum)
		update_ipv6_checksum(skb, l4_proto, addr, new_addr);

	skb_clear_hash(skb);
	ovs_ct_clear(skb, NULL);
	memcpy(addr, new_addr, sizeof(__be32[4]));
}

static void set_ipv6_dsfield(struct sk_buff *skb, struct ipv6hdr *nh, u8 ipv6_tclass, u8 mask)
{
	u8 old_ipv6_tclass = ipv6_get_dsfield(nh);

	ipv6_tclass = OVS_MASKED(old_ipv6_tclass, ipv6_tclass, mask);

	if (skb->ip_summed == CHECKSUM_COMPLETE)
		csum_replace(&skb->csum, (__force __wsum)(old_ipv6_tclass << 12),
			     (__force __wsum)(ipv6_tclass << 12));

	ipv6_change_dsfield(nh, ~mask, ipv6_tclass);
}

static void set_ipv6_fl(struct sk_buff *skb, struct ipv6hdr *nh, u32 fl, u32 mask)
{
	u32 ofl;

	ofl = nh->flow_lbl[0] << 16 |  nh->flow_lbl[1] << 8 |  nh->flow_lbl[2];
	fl = OVS_MASKED(ofl, fl, mask);

	/* Bits 21-24 are always unmasked, so this retains their values. */
	nh->flow_lbl[0] = (u8)(fl >> 16);
	nh->flow_lbl[1] = (u8)(fl >> 8);
	nh->flow_lbl[2] = (u8)fl;

	if (skb->ip_summed == CHECKSUM_COMPLETE)
		csum_replace(&skb->csum, (__force __wsum)htonl(ofl), (__force __wsum)htonl(fl));
}

static void set_ipv6_ttl(struct sk_buff *skb, struct ipv6hdr *nh, u8 new_ttl, u8 mask)
{
	new_ttl = OVS_MASKED(nh->hop_limit, new_ttl, mask);

	if (skb->ip_summed == CHECKSUM_COMPLETE)
		csum_replace(&skb->csum, (__force __wsum)(nh->hop_limit << 8),
			     (__force __wsum)(new_ttl << 8));
	nh->hop_limit = new_ttl;
}

static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
		       u8 mask)
{
	new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);

	csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
	nh->ttl = new_ttl;
}

static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
		    const struct ovs_key_ipv4 *key,
		    const struct ovs_key_ipv4 *mask)
{
	struct iphdr *nh;
	__be32 new_addr;
	int err;

	err = skb_ensure_writable(skb, skb_network_offset(skb) +
				  sizeof(struct iphdr));
	if (unlikely(err))
		return err;

	nh = ip_hdr(skb);

	/* Setting an IP addresses is typically only a side effect of
	 * matching on them in the current userspace implementation, so it
	 * makes sense to check if the value actually changed.
	 */
	if (mask->ipv4_src) {
		new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);

		if (unlikely(new_addr != nh->saddr)) {
			set_ip_addr(skb, nh, &nh->saddr, new_addr);
			flow_key->ipv4.addr.src = new_addr;
		}
	}
	if (mask->ipv4_dst) {
		new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);

		if (unlikely(new_addr != nh->daddr)) {
			set_ip_addr(skb, nh, &nh->daddr, new_addr);
			flow_key->ipv4.addr.dst = new_addr;
		}
	}
	if (mask->ipv4_tos) {
		ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
		flow_key->ip.tos = nh->tos;
	}
	if (mask->ipv4_ttl) {
		set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
		flow_key->ip.ttl = nh->ttl;
	}

	return 0;
}

static bool is_ipv6_mask_nonzero(const __be32 addr[4])
{
	return !!(addr[0] | addr[1] | addr[2] | addr[3]);
}

static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
		    const struct ovs_key_ipv6 *key,
		    const struct ovs_key_ipv6 *mask)
{
	struct ipv6hdr *nh;
	int err;

	err = skb_ensure_writable(skb, skb_network_offset(skb) +
				  sizeof(struct ipv6hdr));
	if (unlikely(err))
		return err;

	nh = ipv6_hdr(skb);

	/* Setting an IP addresses is typically only a side effect of
	 * matching on them in the current userspace implementation, so it
	 * makes sense to check if the value actually changed.
	 */
	if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
		__be32 *saddr = (__be32 *)&nh->saddr;
		__be32 masked[4];

		mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);

		if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
			set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked,
				      true);
			memcpy(&flow_key->ipv6.addr.src, masked,
			       sizeof(flow_key->ipv6.addr.src));
		}
	}
	if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
		unsigned int offset = 0;
		int flags = IP6_FH_F_SKIP_RH;
		bool recalc_csum = true;
		__be32 *daddr = (__be32 *)&nh->daddr;
		__be32 masked[4];

		mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);

		if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
			if (ipv6_ext_hdr(nh->nexthdr))
				recalc_csum = (ipv6_find_hdr(skb, &offset,
							     NEXTHDR_ROUTING,
							     NULL, &flags)
					       != NEXTHDR_ROUTING);

			set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked,
				      recalc_csum);
			memcpy(&flow_key->ipv6.addr.dst, masked,
			       sizeof(flow_key->ipv6.addr.dst));
		}
	}
	if (mask->ipv6_tclass) {
		set_ipv6_dsfield(skb, nh, key->ipv6_tclass, mask->ipv6_tclass);
		flow_key->ip.tos = ipv6_get_dsfield(nh);
	}
	if (mask->ipv6_label) {
		set_ipv6_fl(skb, nh, ntohl(key->ipv6_label),
			    ntohl(mask->ipv6_label));
		flow_key->ipv6.label =
		    *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
	}
	if (mask->ipv6_hlimit) {
		set_ipv6_ttl(skb, nh, key->ipv6_hlimit, mask->ipv6_hlimit);
		flow_key->ip.ttl = nh->hop_limit;
	}
	return 0;
}

static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key,
		   const struct nlattr *a)
{
	struct nshhdr *nh;
	size_t length;
	int err;
	u8 flags;
	u8 ttl;
	int i;

	struct ovs_key_nsh key;
	struct ovs_key_nsh mask;

	err = nsh_key_from_nlattr(a, &key, &mask);
	if (err)
		return err;

	/* Make sure the NSH base header is there */
	if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN))
		return -ENOMEM;

	nh = nsh_hdr(skb);
	length = nsh_hdr_len(nh);

	/* Make sure the whole NSH header is there */
	err = skb_ensure_writable(skb, skb_network_offset(skb) +
				       length);
	if (unlikely(err))
		return err;

	nh = nsh_hdr(skb);
	skb_postpull_rcsum(skb, nh, length);
	flags = nsh_get_flags(nh);
	flags = OVS_MASKED(flags, key.base.flags, mask.base.flags);
	flow_key->nsh.base.flags = flags;
	ttl = nsh_get_ttl(nh);
	ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl);
	flow_key->nsh.base.ttl = ttl;
	nsh_set_flags_and_ttl(nh, flags, ttl);
	nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr,
				  mask.base.path_hdr);
	flow_key->nsh.base.path_hdr = nh->path_hdr;
	switch (nh->mdtype) {
	case NSH_M_TYPE1:
		for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) {
			nh->md1.context[i] =
			    OVS_MASKED(nh->md1.context[i], key.context[i],
				       mask.context[i]);
		}
		memcpy(flow_key->nsh.context, nh->md1.context,
		       sizeof(nh->md1.context));
		break;
	case NSH_M_TYPE2:
		memset(flow_key->nsh.context, 0,
		       sizeof(flow_key->nsh.context));
		break;
	default:
		return -EINVAL;
	}
	skb_postpush_rcsum(skb, nh, length);
	return 0;
}

/* Must follow skb_ensure_writable() since that can move the skb data. */
static void set_tp_port(struct sk_buff *skb, __be16 *port,
			__be16 new_port, __sum16 *check)
{
	ovs_ct_clear(skb, NULL);
	inet_proto_csum_replace2(check, skb, *port, new_port, false);
	*port = new_port;
}

static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
		   const struct ovs_key_udp *key,
		   const struct ovs_key_udp *mask)
{
	struct udphdr *uh;
	__be16 src, dst;
	int err;

	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
				  sizeof(struct udphdr));
	if (unlikely(err))
		return err;

	uh = udp_hdr(skb);
	/* Either of the masks is non-zero, so do not bother checking them. */
	src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
	dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);

	if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
		if (likely(src != uh->source)) {
			set_tp_port(skb, &uh->source, src, &uh->check);
			flow_key->tp.src = src;
		}
		if (likely(dst != uh->dest)) {
			set_tp_port(skb, &uh->dest, dst, &uh->check);
			flow_key->tp.dst = dst;
		}

		if (unlikely(!uh->check))
			uh->check = CSUM_MANGLED_0;
	} else {
		uh->source = src;
		uh->dest = dst;
		flow_key->tp.src = src;
		flow_key->tp.dst = dst;
		ovs_ct_clear(skb, NULL);
	}

	skb_clear_hash(skb);

	return 0;
}

static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
		   const struct ovs_key_tcp *key,
		   const struct ovs_key_tcp *mask)
{
	struct tcphdr *th;
	__be16 src, dst;
	int err;

	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
				  sizeof(struct tcphdr));
	if (unlikely(err))
		return err;

	th = tcp_hdr(skb);
	src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
	if (likely(src != th->source)) {
		set_tp_port(skb, &th->source, src, &th->check);
		flow_key->tp.src = src;
	}
	dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
	if (likely(dst != th->dest)) {
		set_tp_port(skb, &th->dest, dst, &th->check);
		flow_key->tp.dst = dst;
	}
	skb_clear_hash(skb);

	return 0;
}

static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
		    const struct ovs_key_sctp *key,
		    const struct ovs_key_sctp *mask)
{
	unsigned int sctphoff = skb_transport_offset(skb);
	struct sctphdr *sh;
	__le32 old_correct_csum, new_csum, old_csum;
	int err;

	err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
	if (unlikely(err))
		return err;

	sh = sctp_hdr(skb);
	old_csum = sh->checksum;
	old_correct_csum = sctp_compute_cksum(skb, sctphoff);

	sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
	sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);

	new_csum = sctp_compute_cksum(skb, sctphoff);

	/* Carry any checksum errors through. */
	sh->checksum = old_csum ^ old_correct_csum ^ new_csum;

	skb_clear_hash(skb);
	ovs_ct_clear(skb, NULL);

	flow_key->tp.src = sh->source;
	flow_key->tp.dst = sh->dest;

	return 0;
}

static int ovs_vport_output(struct net *net, struct sock *sk,
			    struct sk_buff *skb)
{
	struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
	struct vport *vport = data->vport;

	if (skb_cow_head(skb, data->l2_len) < 0) {
		kfree_skb(skb);
		return -ENOMEM;
	}

	__skb_dst_copy(skb, data->dst);
	*OVS_CB(skb) = data->cb;
	skb->inner_protocol = data->inner_protocol;
	if (data->vlan_tci & VLAN_CFI_MASK)
		__vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK);
	else
		__vlan_hwaccel_clear_tag(skb);

	/* Reconstruct the MAC header.  */
	skb_push(skb, data->l2_len);
	memcpy(skb->data, &data->l2_data, data->l2_len);
	skb_postpush_rcsum(skb, skb->data, data->l2_len);
	skb_reset_mac_header(skb);

	if (eth_p_mpls(skb->protocol)) {
		skb->inner_network_header = skb->network_header;
		skb_set_network_header(skb, data->network_offset);
		skb_reset_mac_len(skb);
	}

	ovs_vport_send(vport, skb, data->mac_proto);
	return 0;
}

static unsigned int
ovs_dst_get_mtu(const struct dst_entry *dst)
{
	return dst->dev->mtu;
}

static struct dst_ops ovs_dst_ops = {
	.family = AF_UNSPEC,
	.mtu = ovs_dst_get_mtu,
};

/* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
 * ovs_vport_output(), which is called once per fragmented packet.
 */
static void prepare_frag(struct vport *vport, struct sk_buff *skb,
			 u16 orig_network_offset, u8 mac_proto)
{
	unsigned int hlen = skb_network_offset(skb);
	struct ovs_frag_data *data;

	data = this_cpu_ptr(&ovs_frag_data_storage);
	data->dst = skb->_skb_refdst;
	data->vport = vport;
	data->cb = *OVS_CB(skb);
	data->inner_protocol = skb->inner_protocol;
	data->network_offset = orig_network_offset;
	if (skb_vlan_tag_present(skb))
		data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK;
	else
		data->vlan_tci = 0;
	data->vlan_proto = skb->vlan_proto;
	data->mac_proto = mac_proto;
	data->l2_len = hlen;
	memcpy(&data->l2_data, skb->data, hlen);

	memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
	skb_pull(skb, hlen);
}

static void ovs_fragment(struct net *net, struct vport *vport,
			 struct sk_buff *skb, u16 mru,
			 struct sw_flow_key *key)
{
	u16 orig_network_offset = 0;

	if (eth_p_mpls(skb->protocol)) {
		orig_network_offset = skb_network_offset(skb);
		skb->network_header = skb->inner_network_header;
	}

	if (skb_network_offset(skb) > MAX_L2_LEN) {
		OVS_NLERR(1, "L2 header too long to fragment");
		goto err;
	}

	if (key->eth.type == htons(ETH_P_IP)) {
		struct rtable ovs_rt = { 0 };
		unsigned long orig_dst;

		prepare_frag(vport, skb, orig_network_offset,
			     ovs_key_mac_proto(key));
		dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
			 DST_OBSOLETE_NONE, DST_NOCOUNT);
		ovs_rt.dst.dev = vport->dev;

		orig_dst = skb->_skb_refdst;
		skb_dst_set_noref(skb, &ovs_rt.dst);
		IPCB(skb)->frag_max_size = mru;

		ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
		refdst_drop(orig_dst);
	} else if (key->eth.type == htons(ETH_P_IPV6)) {
		unsigned long orig_dst;
		struct rt6_info ovs_rt;

		prepare_frag(vport, skb, orig_network_offset,
			     ovs_key_mac_proto(key));
		memset(&ovs_rt, 0, sizeof(ovs_rt));
		dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
			 DST_OBSOLETE_NONE, DST_NOCOUNT);
		ovs_rt.dst.dev = vport->dev;

		orig_dst = skb->_skb_refdst;
		skb_dst_set_noref(skb, &ovs_rt.dst);
		IP6CB(skb)->frag_max_size = mru;

		ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output);
		refdst_drop(orig_dst);
	} else {
		WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
			  ovs_vport_name(vport), ntohs(key->eth.type), mru,
			  vport->dev->mtu);
		goto err;
	}

	return;
err:
	kfree_skb(skb);
}

static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
		      struct sw_flow_key *key)
{
	struct vport *vport = ovs_vport_rcu(dp, out_port);

	if (likely(vport && netif_carrier_ok(vport->dev))) {
		u16 mru = OVS_CB(skb)->mru;
		u32 cutlen = OVS_CB(skb)->cutlen;

		if (unlikely(cutlen > 0)) {
			if (skb->len - cutlen > ovs_mac_header_len(key))
				pskb_trim(skb, skb->len - cutlen);
			else
				pskb_trim(skb, ovs_mac_header_len(key));
		}

		if (likely(!mru ||
		           (skb->len <= mru + vport->dev->hard_header_len))) {
			ovs_vport_send(vport, skb, ovs_key_mac_proto(key));
		} else if (mru <= vport->dev->mtu) {
			struct net *net = read_pnet(&dp->net);

			ovs_fragment(net, vport, skb, mru, key);
		} else {
			kfree_skb(skb);
		}
	} else {
		kfree_skb(skb);
	}
}

static int output_userspace(struct datapath *dp, struct sk_buff *skb,
			    struct sw_flow_key *key, const struct nlattr *attr,
			    const struct nlattr *actions, int actions_len,
			    uint32_t cutlen)
{
	struct dp_upcall_info upcall;
	const struct nlattr *a;
	int rem;

	memset(&upcall, 0, sizeof(upcall));
	upcall.cmd = OVS_PACKET_CMD_ACTION;
	upcall.mru = OVS_CB(skb)->mru;

	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
	     a = nla_next(a, &rem)) {
		switch (nla_type(a)) {
		case OVS_USERSPACE_ATTR_USERDATA:
			upcall.userdata = a;
			break;

		case OVS_USERSPACE_ATTR_PID:
			if (dp->user_features &
			    OVS_DP_F_DISPATCH_UPCALL_PER_CPU)
				upcall.portid =
				  ovs_dp_get_upcall_portid(dp,
							   smp_processor_id());
			else
				upcall.portid = nla_get_u32(a);
			break;

		case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
			/* Get out tunnel info. */
			struct vport *vport;

			vport = ovs_vport_rcu(dp, nla_get_u32(a));
			if (vport) {
				int err;

				err = dev_fill_metadata_dst(vport->dev, skb);
				if (!err)
					upcall.egress_tun_info = skb_tunnel_info(skb);
			}

			break;
		}

		case OVS_USERSPACE_ATTR_ACTIONS: {
			/* Include actions. */
			upcall.actions = actions;
			upcall.actions_len = actions_len;
			break;
		}

		} /* End of switch. */
	}

	return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
}

static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb,
				     struct sw_flow_key *key,
				     const struct nlattr *attr)
{
	/* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */
	struct nlattr *actions = nla_data(attr);

	if (nla_len(actions))
		return clone_execute(dp, skb, key, 0, nla_data(actions),
				     nla_len(actions), true, false);

	consume_skb(skb);
	return 0;
}

/* When 'last' is true, sample() should always consume the 'skb'.
 * Otherwise, sample() should keep 'skb' intact regardless what
 * actions are executed within sample().
 */
static int sample(struct datapath *dp, struct sk_buff *skb,
		  struct sw_flow_key *key, const struct nlattr *attr,
		  bool last)
{
	struct nlattr *actions;
	struct nlattr *sample_arg;
	int rem = nla_len(attr);
	const struct sample_arg *arg;
	bool clone_flow_key;

	/* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */
	sample_arg = nla_data(attr);
	arg = nla_data(sample_arg);
	actions = nla_next(sample_arg, &rem);

	if ((arg->probability != U32_MAX) &&
	    (!arg->probability || get_random_u32() > arg->probability)) {
		if (last)
			consume_skb(skb);
		return 0;
	}

	clone_flow_key = !arg->exec;
	return clone_execute(dp, skb, key, 0, actions, rem, last,
			     clone_flow_key);
}

/* When 'last' is true, clone() should always consume the 'skb'.
 * Otherwise, clone() should keep 'skb' intact regardless what
 * actions are executed within clone().
 */
static int clone(struct datapath *dp, struct sk_buff *skb,
		 struct sw_flow_key *key, const struct nlattr *attr,
		 bool last)
{
	struct nlattr *actions;
	struct nlattr *clone_arg;
	int rem = nla_len(attr);
	bool dont_clone_flow_key;

	/* The first action is always 'OVS_CLONE_ATTR_EXEC'. */
	clone_arg = nla_data(attr);
	dont_clone_flow_key = nla_get_u32(clone_arg);
	actions = nla_next(clone_arg, &rem);

	return clone_execute(dp, skb, key, 0, actions, rem, last,
			     !dont_clone_flow_key);
}

static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
			 const struct nlattr *attr)
{
	struct ovs_action_hash *hash_act = nla_data(attr);
	u32 hash = 0;

	/* OVS_HASH_ALG_L4 is the only possible hash algorithm.  */
	hash = skb_get_hash(skb);
	hash = jhash_1word(hash, hash_act->hash_basis);
	if (!hash)
		hash = 0x1;

	key->ovs_flow_hash = hash;
}

static int execute_set_action(struct sk_buff *skb,
			      struct sw_flow_key *flow_key,
			      const struct nlattr *a)
{
	/* Only tunnel set execution is supported without a mask. */
	if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
		struct ovs_tunnel_info *tun = nla_data(a);

		skb_dst_drop(skb);
		dst_hold((struct dst_entry *)tun->tun_dst);
		skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
		return 0;
	}

	return -EINVAL;
}

/* Mask is at the midpoint of the data. */
#define get_mask(a, type) ((const type)nla_data(a) + 1)

static int execute_masked_set_action(struct sk_buff *skb,
				     struct sw_flow_key *flow_key,
				     const struct nlattr *a)
{
	int err = 0;

	switch (nla_type(a)) {
	case OVS_KEY_ATTR_PRIORITY:
		OVS_SET_MASKED(skb->priority, nla_get_u32(a),
			       *get_mask(a, u32 *));
		flow_key->phy.priority = skb->priority;
		break;

	case OVS_KEY_ATTR_SKB_MARK:
		OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
		flow_key->phy.skb_mark = skb->mark;
		break;

	case OVS_KEY_ATTR_TUNNEL_INFO:
		/* Masked data not supported for tunnel. */
		err = -EINVAL;
		break;

	case OVS_KEY_ATTR_ETHERNET:
		err = set_eth_addr(skb, flow_key, nla_data(a),
				   get_mask(a, struct ovs_key_ethernet *));
		break;

	case OVS_KEY_ATTR_NSH:
		err = set_nsh(skb, flow_key, a);
		break;

	case OVS_KEY_ATTR_IPV4:
		err = set_ipv4(skb, flow_key, nla_data(a),
			       get_mask(a, struct ovs_key_ipv4 *));
		break;

	case OVS_KEY_ATTR_IPV6:
		err = set_ipv6(skb, flow_key, nla_data(a),
			       get_mask(a, struct ovs_key_ipv6 *));
		break;

	case OVS_KEY_ATTR_TCP:
		err = set_tcp(skb, flow_key, nla_data(a),
			      get_mask(a, struct ovs_key_tcp *));
		break;

	case OVS_KEY_ATTR_UDP:
		err = set_udp(skb, flow_key, nla_data(a),
			      get_mask(a, struct ovs_key_udp *));
		break;

	case OVS_KEY_ATTR_SCTP:
		err = set_sctp(skb, flow_key, nla_data(a),
			       get_mask(a, struct ovs_key_sctp *));
		break;

	case OVS_KEY_ATTR_MPLS:
		err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
								    __be32 *));
		break;

	case OVS_KEY_ATTR_CT_STATE:
	case OVS_KEY_ATTR_CT_ZONE:
	case OVS_KEY_ATTR_CT_MARK:
	case OVS_KEY_ATTR_CT_LABELS:
	case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4:
	case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6:
		err = -EINVAL;
		break;
	}

	return err;
}

static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
			  struct sw_flow_key *key,
			  const struct nlattr *a, bool last)
{
	u32 recirc_id;

	if (!is_flow_key_valid(key)) {
		int err;

		err = ovs_flow_key_update(skb, key);
		if (err)
			return err;
	}
	BUG_ON(!is_flow_key_valid(key));

	recirc_id = nla_get_u32(a);
	return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true);
}

static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb,
				 struct sw_flow_key *key,
				 const struct nlattr *attr, bool last)
{
	struct ovs_skb_cb *ovs_cb = OVS_CB(skb);
	const struct nlattr *actions, *cpl_arg;
	int len, max_len, rem = nla_len(attr);
	const struct check_pkt_len_arg *arg;
	bool clone_flow_key;

	/* The first netlink attribute in 'attr' is always
	 * 'OVS_CHECK_PKT_LEN_ATTR_ARG'.
	 */
	cpl_arg = nla_data(attr);
	arg = nla_data(cpl_arg);

	len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len;
	max_len = arg->pkt_len;

	if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) ||
	    len <= max_len) {
		/* Second netlink attribute in 'attr' is always
		 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'.
		 */
		actions = nla_next(cpl_arg, &rem);
		clone_flow_key = !arg->exec_for_lesser_equal;
	} else {
		/* Third netlink attribute in 'attr' is always
		 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'.
		 */
		actions = nla_next(cpl_arg, &rem);
		actions = nla_next(actions, &rem);
		clone_flow_key = !arg->exec_for_greater;
	}

	return clone_execute(dp, skb, key, 0, nla_data(actions),
			     nla_len(actions), last, clone_flow_key);
}

static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key)
{
	int err;

	if (skb->protocol == htons(ETH_P_IPV6)) {
		struct ipv6hdr *nh;

		err = skb_ensure_writable(skb, skb_network_offset(skb) +
					  sizeof(*nh));
		if (unlikely(err))
			return err;

		nh = ipv6_hdr(skb);

		if (nh->hop_limit <= 1)
			return -EHOSTUNREACH;

		key->ip.ttl = --nh->hop_limit;
	} else if (skb->protocol == htons(ETH_P_IP)) {
		struct iphdr *nh;
		u8 old_ttl;

		err = skb_ensure_writable(skb, skb_network_offset(skb) +
					  sizeof(*nh));
		if (unlikely(err))
			return err;

		nh = ip_hdr(skb);
		if (nh->ttl <= 1)
			return -EHOSTUNREACH;

		old_ttl = nh->ttl--;
		csum_replace2(&nh->check, htons(old_ttl << 8),
			      htons(nh->ttl << 8));
		key->ip.ttl = nh->ttl;
	}
	return 0;
}

/* Execute a list of actions against 'skb'. */
static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
			      struct sw_flow_key *key,
			      const struct nlattr *attr, int len)
{
	const struct nlattr *a;
	int rem;

	for (a = attr, rem = len; rem > 0;
	     a = nla_next(a, &rem)) {
		int err = 0;

		if (trace_ovs_do_execute_action_enabled())
			trace_ovs_do_execute_action(dp, skb, key, a, rem);

		switch (nla_type(a)) {
		case OVS_ACTION_ATTR_OUTPUT: {
			int port = nla_get_u32(a);
			struct sk_buff *clone;

			/* Every output action needs a separate clone
			 * of 'skb', In case the output action is the
			 * last action, cloning can be avoided.
			 */
			if (nla_is_last(a, rem)) {
				do_output(dp, skb, port, key);
				/* 'skb' has been used for output.
				 */
				return 0;
			}

			clone = skb_clone(skb, GFP_ATOMIC);
			if (clone)
				do_output(dp, clone, port, key);
			OVS_CB(skb)->cutlen = 0;
			break;
		}

		case OVS_ACTION_ATTR_TRUNC: {
			struct ovs_action_trunc *trunc = nla_data(a);

			if (skb->len > trunc->max_len)
				OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
			break;
		}

		case OVS_ACTION_ATTR_USERSPACE:
			output_userspace(dp, skb, key, a, attr,
						     len, OVS_CB(skb)->cutlen);
			OVS_CB(skb)->cutlen = 0;
			break;

		case OVS_ACTION_ATTR_HASH:
			execute_hash(skb, key, a);
			break;

		case OVS_ACTION_ATTR_PUSH_MPLS: {
			struct ovs_action_push_mpls *mpls = nla_data(a);

			err = push_mpls(skb, key, mpls->mpls_lse,
					mpls->mpls_ethertype, skb->mac_len);
			break;
		}
		case OVS_ACTION_ATTR_ADD_MPLS: {
			struct ovs_action_add_mpls *mpls = nla_data(a);
			__u16 mac_len = 0;

			if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK)
				mac_len = skb->mac_len;

			err = push_mpls(skb, key, mpls->mpls_lse,
					mpls->mpls_ethertype, mac_len);
			break;
		}
		case OVS_ACTION_ATTR_POP_MPLS:
			err = pop_mpls(skb, key, nla_get_be16(a));
			break;

		case OVS_ACTION_ATTR_PUSH_VLAN:
			err = push_vlan(skb, key, nla_data(a));
			break;

		case OVS_ACTION_ATTR_POP_VLAN:
			err = pop_vlan(skb, key);
			break;

		case OVS_ACTION_ATTR_RECIRC: {
			bool last = nla_is_last(a, rem);

			err = execute_recirc(dp, skb, key, a, last);
			if (last) {
				/* If this is the last action, the skb has
				 * been consumed or freed.
				 * Return immediately.
				 */
				return err;
			}
			break;
		}

		case OVS_ACTION_ATTR_SET:
			err = execute_set_action(skb, key, nla_data(a));
			break;

		case OVS_ACTION_ATTR_SET_MASKED:
		case OVS_ACTION_ATTR_SET_TO_MASKED:
			err = execute_masked_set_action(skb, key, nla_data(a));
			break;

		case OVS_ACTION_ATTR_SAMPLE: {
			bool last = nla_is_last(a, rem);

			err = sample(dp, skb, key, a, last);
			if (last)
				return err;

			break;
		}

		case OVS_ACTION_ATTR_CT:
			if (!is_flow_key_valid(key)) {
				err = ovs_flow_key_update(skb, key);
				if (err)
					return err;
			}

			err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
					     nla_data(a));

			/* Hide stolen IP fragments from user space. */
			if (err)
				return err == -EINPROGRESS ? 0 : err;
			break;

		case OVS_ACTION_ATTR_CT_CLEAR:
			err = ovs_ct_clear(skb, key);
			break;

		case OVS_ACTION_ATTR_PUSH_ETH:
			err = push_eth(skb, key, nla_data(a));
			break;

		case OVS_ACTION_ATTR_POP_ETH:
			err = pop_eth(skb, key);
			break;

		case OVS_ACTION_ATTR_PUSH_NSH: {
			u8 buffer[NSH_HDR_MAX_LEN];
			struct nshhdr *nh = (struct nshhdr *)buffer;

			err = nsh_hdr_from_nlattr(nla_data(a), nh,
						  NSH_HDR_MAX_LEN);
			if (unlikely(err))
				break;
			err = push_nsh(skb, key, nh);
			break;
		}

		case OVS_ACTION_ATTR_POP_NSH:
			err = pop_nsh(skb, key);
			break;

		case OVS_ACTION_ATTR_METER:
			if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) {
				consume_skb(skb);
				return 0;
			}
			break;

		case OVS_ACTION_ATTR_CLONE: {
			bool last = nla_is_last(a, rem);

			err = clone(dp, skb, key, a, last);
			if (last)
				return err;

			break;
		}

		case OVS_ACTION_ATTR_CHECK_PKT_LEN: {
			bool last = nla_is_last(a, rem);

			err = execute_check_pkt_len(dp, skb, key, a, last);
			if (last)
				return err;

			break;
		}

		case OVS_ACTION_ATTR_DEC_TTL:
			err = execute_dec_ttl(skb, key);
			if (err == -EHOSTUNREACH)
				return dec_ttl_exception_handler(dp, skb,
								 key, a);
			break;
		}

		if (unlikely(err)) {
			kfree_skb(skb);
			return err;
		}
	}

	consume_skb(skb);
	return 0;
}

/* Execute the actions on the clone of the packet. The effect of the
 * execution does not affect the original 'skb' nor the original 'key'.
 *
 * The execution may be deferred in case the actions can not be executed
 * immediately.
 */
static int clone_execute(struct datapath *dp, struct sk_buff *skb,
			 struct sw_flow_key *key, u32 recirc_id,
			 const struct nlattr *actions, int len,
			 bool last, bool clone_flow_key)
{
	struct deferred_action *da;
	struct sw_flow_key *clone;

	skb = last ? skb : skb_clone(skb, GFP_ATOMIC);
	if (!skb) {
		/* Out of memory, skip this action.
		 */
		return 0;
	}

	/* When clone_flow_key is false, the 'key' will not be change
	 * by the actions, then the 'key' can be used directly.
	 * Otherwise, try to clone key from the next recursion level of
	 * 'flow_keys'. If clone is successful, execute the actions
	 * without deferring.
	 */
	clone = clone_flow_key ? clone_key(key) : key;
	if (clone) {
		int err = 0;

		if (actions) { /* Sample action */
			if (clone_flow_key)
				__this_cpu_inc(exec_actions_level);

			err = do_execute_actions(dp, skb, clone,
						 actions, len);

			if (clone_flow_key)
				__this_cpu_dec(exec_actions_level);
		} else { /* Recirc action */
			clone->recirc_id = recirc_id;
			ovs_dp_process_packet(skb, clone);
		}
		return err;
	}

	/* Out of 'flow_keys' space. Defer actions */
	da = add_deferred_actions(skb, key, actions, len);
	if (da) {
		if (!actions) { /* Recirc action */
			key = &da->pkt_key;
			key->recirc_id = recirc_id;
		}
	} else {
		/* Out of per CPU action FIFO space. Drop the 'skb' and
		 * log an error.
		 */
		kfree_skb(skb);

		if (net_ratelimit()) {
			if (actions) { /* Sample action */
				pr_warn("%s: deferred action limit reached, drop sample action\n",
					ovs_dp_name(dp));
			} else {  /* Recirc action */
				pr_warn("%s: deferred action limit reached, drop recirc action (recirc_id=%#x)\n",
					ovs_dp_name(dp), recirc_id);
			}
		}
	}
	return 0;
}

static void process_deferred_actions(struct datapath *dp)
{
	struct action_fifo *fifo = this_cpu_ptr(action_fifos);

	/* Do not touch the FIFO in case there is no deferred actions. */
	if (action_fifo_is_empty(fifo))
		return;

	/* Finishing executing all deferred actions. */
	do {
		struct deferred_action *da = action_fifo_get(fifo);
		struct sk_buff *skb = da->skb;
		struct sw_flow_key *key = &da->pkt_key;
		const struct nlattr *actions = da->actions;
		int actions_len = da->actions_len;

		if (actions)
			do_execute_actions(dp, skb, key, actions, actions_len);
		else
			ovs_dp_process_packet(skb, key);
	} while (!action_fifo_is_empty(fifo));

	/* Reset FIFO for the next packet.  */
	action_fifo_init(fifo);
}

/* Execute a list of actions against 'skb'. */
int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
			const struct sw_flow_actions *acts,
			struct sw_flow_key *key)
{
	int err, level;

	level = __this_cpu_inc_return(exec_actions_level);
	if (unlikely(level > OVS_RECURSION_LIMIT)) {
		net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
				     ovs_dp_name(dp));
		kfree_skb(skb);
		err = -ENETDOWN;
		goto out;
	}

	OVS_CB(skb)->acts_origlen = acts->orig_len;
	err = do_execute_actions(dp, skb, key,
				 acts->actions, acts->actions_len);

	if (level == 1)
		process_deferred_actions(dp);

out:
	__this_cpu_dec(exec_actions_level);
	return err;
}

int action_fifos_init(void)
{
	action_fifos = alloc_percpu(struct action_fifo);
	if (!action_fifos)
		return -ENOMEM;

	flow_keys = alloc_percpu(struct action_flow_keys);
	if (!flow_keys) {
		free_percpu(action_fifos);
		return -ENOMEM;
	}

	return 0;
}

void action_fifos_exit(void)
{
	free_percpu(action_fifos);
	free_percpu(flow_keys);
}