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_ethertype, mac_len, !!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, ethertype, skb->mac_len, 187 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, 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, 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->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, eth_hdr(skb), ETH_ALEN * 2); 268 269 ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src, 270 mask->eth_src); 271 ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst, 272 mask->eth_dst); 273 274 skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 275 276 ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source); 277 ether_addr_copy(flow_key->eth.dst, 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, ethh->addresses.eth_dst, 304 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(a, nh, NSH_HDR_MAX_LEN); 323 if (err) 324 return err; 325 326 err = nsh_push(skb, 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(&tcp_hdr(skb)->check, skb, 364 addr, new_addr, 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(&uh->check, skb, 371 addr, new_addr, 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, new_addr); 383 csum_replace4(&nh->check, *addr, 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(&tcp_hdr(skb)->check, skb, 397 addr, new_addr, 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(&uh->check, skb, 404 addr, new_addr, 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(&icmp6_hdr(skb)->icmp6_cksum, 412 skb, addr, new_addr, 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(nh); 440 441 ipv6_tclass = OVS_MASKED(old_ipv6_tclass, ipv6_tclass, mask); 442 443 if (skb->ip_summed == CHECKSUM_COMPLETE) 444 csum_replace(&skb->csum, (__force __wsum)(old_ipv6_tclass << 12), 445 (__force __wsum)(ipv6_tclass << 12)); 446 447 ipv6_change_dsfield(nh, ~mask, 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(&skb->csum, (__force __wsum)htonl(ofl), (__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(&skb->csum, (__force __wsum)(nh->hop_limit << 8), 472 (__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(&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, 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, &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, &nh->daddr, new_addr); 517 flow_key->ipv4.addr.dst = new_addr; 518 } 519 } 520 if (mask->ipv4_tos) { 521 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos); 522 flow_key->ip.tos = nh->tos; 523 } 524 if (mask->ipv4_ttl) { 525 set_ip_ttl(skb, nh, key->ipv4_ttl, 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, 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(mask->ipv6_src)) { 556 __be32 *saddr = (__be32 *)&nh->saddr; 557 __be32 masked[4]; 558 559 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked); 560 561 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) { 562 set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked, 563 true); 564 memcpy(&flow_key->ipv6.addr.src, masked, 565 sizeof(flow_key->ipv6.addr.src)); 566 } 567 } 568 if (is_ipv6_mask_nonzero(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(daddr, key->ipv6_dst, mask->ipv6_dst, masked); 576 577 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) { 578 if (ipv6_ext_hdr(nh->nexthdr)) 579 recalc_csum = (ipv6_find_hdr(skb, &offset, 580 NEXTHDR_ROUTING, 581 NULL, &flags) 582 != NEXTHDR_ROUTING); 583 584 set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked, 585 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, key->ipv6_tclass, mask->ipv6_tclass); 592 flow_key->ip.tos = ipv6_get_dsfield(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, key->ipv6_hlimit, 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(a, &key, &mask); 621 if (err) 622 return err; 623 624 /* Make sure the NSH base header is there */ 625 if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN)) 626 return -ENOMEM; 627 628 nh = nsh_hdr(skb); 629 length = nsh_hdr_len(nh); 630 631 /* Make sure the whole NSH header is there */ 632 err = skb_ensure_writable(skb, skb_network_offset(skb) + 633 length); 634 if (unlikely(err)) 635 return err; 636 637 nh = nsh_hdr(skb); 638 skb_postpull_rcsum(skb, nh, length); 639 flags = nsh_get_flags(nh); 640 flags = OVS_MASKED(flags, key.base.flags, mask.base.flags); 641 flow_key->nsh.base.flags = flags; 642 ttl = nsh_get_ttl(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(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, nh, 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(check, skb, *port, new_port, 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, 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, &uh->source, src, &uh->check); 700 flow_key->tp.src = src; 701 } 702 if (likely(dst != uh->dest)) { 703 set_tp_port(skb, &uh->dest, dst, &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, 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, &th->source, src, &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, &th->dest, dst, &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, 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, 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, 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, data->l2_len) < 0) { 792 kfree_skb_reason(skb, SKB_DROP_REASON_NOMEM); 793 return -ENOMEM; 794 } 795 796 __skb_dst_copy(skb, 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, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK); 801 else 802 __vlan_hwaccel_clear_tag(skb); 803 804 /* Reconstruct the MAC header. */ 805 skb_push(skb, data->l2_len); 806 memcpy(skb->data, &data->l2_data, data->l2_len); 807 skb_postpush_rcsum(skb, skb->data, data->l2_len); 808 skb_reset_mac_header(skb); 809 810 if (eth_p_mpls(skb->protocol)) { 811 skb->inner_network_header = skb->network_header; 812 skb_set_network_header(skb, data->network_offset); 813 skb_reset_mac_len(skb); 814 } 815 816 ovs_vport_send(vport, skb, 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, 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(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 ovs_key_mac_proto(key)); 883 dst_init(&ovs_rt.dst, &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, &ovs_rt.dst); 889 IPCB(skb)->frag_max_size = mru; 890 891 ip_do_fragment(net, skb->sk, skb, ovs_vport_output); 892 refdst_drop(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 ovs_key_mac_proto(key)); 899 memset(&ovs_rt, 0, sizeof(ovs_rt)); 900 dst_init(&ovs_rt.dst, &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, &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(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, 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, skb->len - cutlen); 935 else 936 pskb_trim(skb, 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, ovs_key_mac_proto(key)); 942 } else if (mru <= vport->dev->mtu) { 943 struct net *net = read_pnet(&dp->net); 944 945 ovs_fragment(net, vport, skb, mru, key); 946 } else { 947 kfree_skb_reason(skb, SKB_DROP_REASON_PKT_TOO_BIG); 948 } 949 } else { 950 kfree_skb_reason(skb, 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(attr), rem = nla_len(attr); rem > 0; 968 a = nla_next(a, &rem)) { 969 switch (nla_type(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(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, nla_get_u32(a)); 989 if (vport) { 990 int err; 991 992 err = dev_fill_metadata_dst(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(attr); 1019 1020 if (nla_len(actions)) 1021 return clone_execute(dp, skb, key, 0, nla_data(actions), 1022 nla_len(actions), true, false); 1023 1024 ovs_kfree_skb_reason(skb, 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(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(attr); 1044 arg = nla_data(sample_arg); 1045 actions = nla_next(sample_arg, &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, OVS_DROP_LAST_ACTION); 1051 return 0; 1052 } 1053 1054 clone_flow_key = !arg->exec; 1055 return clone_execute(dp, skb, key, 0, actions, 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(attr); 1070 bool dont_clone_flow_key; 1071 1072 /* The first action is always 'OVS_CLONE_ATTR_EXEC'. */ 1073 clone_arg = nla_data(attr); 1074 dont_clone_flow_key = nla_get_u32(clone_arg); 1075 actions = nla_next(clone_arg, &rem); 1076 1077 return clone_execute(dp, skb, key, 0, actions, rem, last, 1078 !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(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(hash, 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(a) == OVS_KEY_ATTR_TUNNEL_INFO) { 1110 struct ovs_tunnel_info *tun = nla_data(a); 1111 1112 skb_dst_drop(skb); 1113 dst_hold((struct dst_entry *)tun->tun_dst); 1114 skb_dst_set(skb, (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(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, nla_data(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, nla_data(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, nla_data(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, nla_data(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, nla_data(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, nla_data(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, nla_data(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(a); 1215 return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, 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(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(attr); 1232 arg = nla_data(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, 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(cpl_arg, &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(cpl_arg, &rem); 1249 actions = nla_next(actions, &rem); 1250 clone_flow_key = !arg->exec_for_greater; 1251 } 1252 1253 return clone_execute(dp, skb, key, 0, nla_data(actions), 1254 nla_len(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, 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, 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(&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(a, &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(a)) { 1315 case OVS_ACTION_ATTR_OUTPUT: { 1316 int port = nla_get_u32(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(a, rem)) { 1324 do_output(dp, skb, 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, clone, 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(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, a, attr, 1347 len, OVS_CB(skb)->cutlen); 1348 OVS_CB(skb)->cutlen = 0; 1349 if (nla_is_last(a, rem)) { 1350 consume_skb(skb); 1351 return 0; 1352 } 1353 break; 1354 1355 case OVS_ACTION_ATTR_HASH: 1356 execute_hash(skb, key, a); 1357 break; 1358 1359 case OVS_ACTION_ATTR_PUSH_MPLS: { 1360 struct ovs_action_push_mpls *mpls = nla_data(a); 1361 1362 err = push_mpls(skb, key, mpls->mpls_lse, 1363 mpls->mpls_ethertype, skb->mac_len); 1364 break; 1365 } 1366 case OVS_ACTION_ATTR_ADD_MPLS: { 1367 struct ovs_action_add_mpls *mpls = nla_data(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->mpls_lse, 1374 mpls->mpls_ethertype, mac_len); 1375 break; 1376 } 1377 case OVS_ACTION_ATTR_POP_MPLS: 1378 err = pop_mpls(skb, key, nla_get_be16(a)); 1379 break; 1380 1381 case OVS_ACTION_ATTR_PUSH_VLAN: 1382 err = push_vlan(skb, key, nla_data(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(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, key, nla_data(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, key, nla_data(a)); 1410 break; 1411 1412 case OVS_ACTION_ATTR_SAMPLE: { 1413 bool last = nla_is_last(a, rem); 1414 1415 err = sample(dp, skb, key, 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(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, nla_data(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, nla_data(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, nla_get_u32(a))) { 1459 ovs_kfree_skb_reason(skb, OVS_DROP_METER); 1460 return 0; 1461 } 1462 break; 1463 1464 case OVS_ACTION_ATTR_CLONE: { 1465 bool last = nla_is_last(a, rem); 1466 1467 err = clone(dp, skb, key, 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(a, rem); 1476 1477 err = execute_check_pkt_len(dp, skb, key, 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, a); 1489 break; 1490 1491 case OVS_ACTION_ATTR_DROP: { 1492 enum ovs_drop_reason reason = nla_get_u32(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, OVS_DROP_ACTION_ERROR); 1503 return err; 1504 } 1505 } 1506 1507 ovs_kfree_skb_reason(skb, 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; 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, clone, 1547 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, clone); 1554 } 1555 return err; 1556 } 1557 1558 /* Out of 'flow_keys' space. Defer actions */ 1559 da = add_deferred_actions(skb, key, actions, 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, 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, actions, 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, 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 acts->actions, 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(action_fifos); 1647 return -ENOMEM; 1648 } 1649 1650 return 0; 1651} 1652 1653void action_fifos_exit(void) 1654{ 1655 free_percpu(action_fifos); 1656 free_percpu(flow_keys); 1657} 1658