1 /* 2 * Copyright (c) 2007-2014 Nicira, Inc. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of version 2 of the GNU General Public 6 * License as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program; if not, write to the Free Software 15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 16 * 02110-1301, USA 17 */ 18 19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 20 21 #include <linux/skbuff.h> 22 #include <linux/in.h> 23 #include <linux/ip.h> 24 #include <linux/openvswitch.h> 25 #include <linux/netfilter_ipv6.h> 26 #include <linux/sctp.h> 27 #include <linux/tcp.h> 28 #include <linux/udp.h> 29 #include <linux/in6.h> 30 #include <linux/if_arp.h> 31 #include <linux/if_vlan.h> 32 33 #include <net/dst.h> 34 #include <net/ip.h> 35 #include <net/ipv6.h> 36 #include <net/ip6_fib.h> 37 #include <net/checksum.h> 38 #include <net/dsfield.h> 39 #include <net/mpls.h> 40 #include <net/sctp/checksum.h> 41 42 #include "datapath.h" 43 #include "flow.h" 44 #include "conntrack.h" 45 #include "vport.h" 46 47 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 48 struct sw_flow_key *key, 49 const struct nlattr *attr, int len); 50 51 struct deferred_action { 52 struct sk_buff *skb; 53 const struct nlattr *actions; 54 55 /* Store pkt_key clone when creating deferred action. */ 56 struct sw_flow_key pkt_key; 57 }; 58 59 #define MAX_L2_LEN (VLAN_ETH_HLEN + 3 * MPLS_HLEN) 60 struct ovs_frag_data { 61 unsigned long dst; 62 struct vport *vport; 63 struct ovs_skb_cb cb; 64 __be16 inner_protocol; 65 __u16 vlan_tci; 66 __be16 vlan_proto; 67 unsigned int l2_len; 68 u8 l2_data[MAX_L2_LEN]; 69 }; 70 71 static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage); 72 73 #define DEFERRED_ACTION_FIFO_SIZE 10 74 #define OVS_RECURSION_LIMIT 5 75 #define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2) 76 struct action_fifo { 77 int head; 78 int tail; 79 /* Deferred action fifo queue storage. */ 80 struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE]; 81 }; 82 83 struct recirc_keys { 84 struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD]; 85 }; 86 87 static struct action_fifo __percpu *action_fifos; 88 static struct recirc_keys __percpu *recirc_keys; 89 static DEFINE_PER_CPU(int, exec_actions_level); 90 91 static void action_fifo_init(struct action_fifo *fifo) 92 { 93 fifo->head = 0; 94 fifo->tail = 0; 95 } 96 97 static bool action_fifo_is_empty(const struct action_fifo *fifo) 98 { 99 return (fifo->head == fifo->tail); 100 } 101 102 static struct deferred_action *action_fifo_get(struct action_fifo *fifo) 103 { 104 if (action_fifo_is_empty(fifo)) 105 return NULL; 106 107 return &fifo->fifo[fifo->tail++]; 108 } 109 110 static struct deferred_action *action_fifo_put(struct action_fifo *fifo) 111 { 112 if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1) 113 return NULL; 114 115 return &fifo->fifo[fifo->head++]; 116 } 117 118 /* Return true if fifo is not full */ 119 static struct deferred_action *add_deferred_actions(struct sk_buff *skb, 120 const struct sw_flow_key *key, 121 const struct nlattr *attr) 122 { 123 struct action_fifo *fifo; 124 struct deferred_action *da; 125 126 fifo = this_cpu_ptr(action_fifos); 127 da = action_fifo_put(fifo); 128 if (da) { 129 da->skb = skb; 130 da->actions = attr; 131 da->pkt_key = *key; 132 } 133 134 return da; 135 } 136 137 static void invalidate_flow_key(struct sw_flow_key *key) 138 { 139 key->eth.type = htons(0); 140 } 141 142 static bool is_flow_key_valid(const struct sw_flow_key *key) 143 { 144 return !!key->eth.type; 145 } 146 147 static void update_ethertype(struct sk_buff *skb, struct ethhdr *hdr, 148 __be16 ethertype) 149 { 150 if (skb->ip_summed == CHECKSUM_COMPLETE) { 151 __be16 diff[] = { ~(hdr->h_proto), ethertype }; 152 153 skb->csum = ~csum_partial((char *)diff, sizeof(diff), 154 ~skb->csum); 155 } 156 157 hdr->h_proto = ethertype; 158 } 159 160 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key, 161 const struct ovs_action_push_mpls *mpls) 162 { 163 struct mpls_shim_hdr *new_mpls_lse; 164 165 /* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */ 166 if (skb->encapsulation) 167 return -ENOTSUPP; 168 169 if (skb_cow_head(skb, MPLS_HLEN) < 0) 170 return -ENOMEM; 171 172 if (!skb->inner_protocol) { 173 skb_set_inner_network_header(skb, skb->mac_len); 174 skb_set_inner_protocol(skb, skb->protocol); 175 } 176 177 skb_push(skb, MPLS_HLEN); 178 memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb), 179 skb->mac_len); 180 skb_reset_mac_header(skb); 181 skb_set_network_header(skb, skb->mac_len); 182 183 new_mpls_lse = mpls_hdr(skb); 184 new_mpls_lse->label_stack_entry = mpls->mpls_lse; 185 186 skb_postpush_rcsum(skb, new_mpls_lse, MPLS_HLEN); 187 188 update_ethertype(skb, eth_hdr(skb), mpls->mpls_ethertype); 189 skb->protocol = mpls->mpls_ethertype; 190 191 invalidate_flow_key(key); 192 return 0; 193 } 194 195 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key, 196 const __be16 ethertype) 197 { 198 struct ethhdr *hdr; 199 int err; 200 201 err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN); 202 if (unlikely(err)) 203 return err; 204 205 skb_postpull_rcsum(skb, mpls_hdr(skb), MPLS_HLEN); 206 207 memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb), 208 skb->mac_len); 209 210 __skb_pull(skb, MPLS_HLEN); 211 skb_reset_mac_header(skb); 212 skb_set_network_header(skb, skb->mac_len); 213 214 /* mpls_hdr() is used to locate the ethertype field correctly in the 215 * presence of VLAN tags. 216 */ 217 hdr = (struct ethhdr *)((void *)mpls_hdr(skb) - ETH_HLEN); 218 update_ethertype(skb, hdr, ethertype); 219 if (eth_p_mpls(skb->protocol)) 220 skb->protocol = ethertype; 221 222 invalidate_flow_key(key); 223 return 0; 224 } 225 226 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key, 227 const __be32 *mpls_lse, const __be32 *mask) 228 { 229 struct mpls_shim_hdr *stack; 230 __be32 lse; 231 int err; 232 233 err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN); 234 if (unlikely(err)) 235 return err; 236 237 stack = mpls_hdr(skb); 238 lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask); 239 if (skb->ip_summed == CHECKSUM_COMPLETE) { 240 __be32 diff[] = { ~(stack->label_stack_entry), lse }; 241 242 skb->csum = ~csum_partial((char *)diff, sizeof(diff), 243 ~skb->csum); 244 } 245 246 stack->label_stack_entry = lse; 247 flow_key->mpls.top_lse = lse; 248 return 0; 249 } 250 251 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key) 252 { 253 int err; 254 255 err = skb_vlan_pop(skb); 256 if (skb_vlan_tag_present(skb)) { 257 invalidate_flow_key(key); 258 } else { 259 key->eth.vlan.tci = 0; 260 key->eth.vlan.tpid = 0; 261 } 262 return err; 263 } 264 265 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key, 266 const struct ovs_action_push_vlan *vlan) 267 { 268 if (skb_vlan_tag_present(skb)) { 269 invalidate_flow_key(key); 270 } else { 271 key->eth.vlan.tci = vlan->vlan_tci; 272 key->eth.vlan.tpid = vlan->vlan_tpid; 273 } 274 return skb_vlan_push(skb, vlan->vlan_tpid, 275 ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT); 276 } 277 278 /* 'src' is already properly masked. */ 279 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_) 280 { 281 u16 *dst = (u16 *)dst_; 282 const u16 *src = (const u16 *)src_; 283 const u16 *mask = (const u16 *)mask_; 284 285 OVS_SET_MASKED(dst[0], src[0], mask[0]); 286 OVS_SET_MASKED(dst[1], src[1], mask[1]); 287 OVS_SET_MASKED(dst[2], src[2], mask[2]); 288 } 289 290 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key, 291 const struct ovs_key_ethernet *key, 292 const struct ovs_key_ethernet *mask) 293 { 294 int err; 295 296 err = skb_ensure_writable(skb, ETH_HLEN); 297 if (unlikely(err)) 298 return err; 299 300 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 301 302 ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src, 303 mask->eth_src); 304 ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst, 305 mask->eth_dst); 306 307 skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 308 309 ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source); 310 ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest); 311 return 0; 312 } 313 314 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh, 315 __be32 addr, __be32 new_addr) 316 { 317 int transport_len = skb->len - skb_transport_offset(skb); 318 319 if (nh->frag_off & htons(IP_OFFSET)) 320 return; 321 322 if (nh->protocol == IPPROTO_TCP) { 323 if (likely(transport_len >= sizeof(struct tcphdr))) 324 inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb, 325 addr, new_addr, true); 326 } else if (nh->protocol == IPPROTO_UDP) { 327 if (likely(transport_len >= sizeof(struct udphdr))) { 328 struct udphdr *uh = udp_hdr(skb); 329 330 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 331 inet_proto_csum_replace4(&uh->check, skb, 332 addr, new_addr, true); 333 if (!uh->check) 334 uh->check = CSUM_MANGLED_0; 335 } 336 } 337 } 338 } 339 340 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh, 341 __be32 *addr, __be32 new_addr) 342 { 343 update_ip_l4_checksum(skb, nh, *addr, new_addr); 344 csum_replace4(&nh->check, *addr, new_addr); 345 skb_clear_hash(skb); 346 *addr = new_addr; 347 } 348 349 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto, 350 __be32 addr[4], const __be32 new_addr[4]) 351 { 352 int transport_len = skb->len - skb_transport_offset(skb); 353 354 if (l4_proto == NEXTHDR_TCP) { 355 if (likely(transport_len >= sizeof(struct tcphdr))) 356 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb, 357 addr, new_addr, true); 358 } else if (l4_proto == NEXTHDR_UDP) { 359 if (likely(transport_len >= sizeof(struct udphdr))) { 360 struct udphdr *uh = udp_hdr(skb); 361 362 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 363 inet_proto_csum_replace16(&uh->check, skb, 364 addr, new_addr, true); 365 if (!uh->check) 366 uh->check = CSUM_MANGLED_0; 367 } 368 } 369 } else if (l4_proto == NEXTHDR_ICMP) { 370 if (likely(transport_len >= sizeof(struct icmp6hdr))) 371 inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum, 372 skb, addr, new_addr, true); 373 } 374 } 375 376 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4], 377 const __be32 mask[4], __be32 masked[4]) 378 { 379 masked[0] = OVS_MASKED(old[0], addr[0], mask[0]); 380 masked[1] = OVS_MASKED(old[1], addr[1], mask[1]); 381 masked[2] = OVS_MASKED(old[2], addr[2], mask[2]); 382 masked[3] = OVS_MASKED(old[3], addr[3], mask[3]); 383 } 384 385 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto, 386 __be32 addr[4], const __be32 new_addr[4], 387 bool recalculate_csum) 388 { 389 if (recalculate_csum) 390 update_ipv6_checksum(skb, l4_proto, addr, new_addr); 391 392 skb_clear_hash(skb); 393 memcpy(addr, new_addr, sizeof(__be32[4])); 394 } 395 396 static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask) 397 { 398 /* Bits 21-24 are always unmasked, so this retains their values. */ 399 OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16)); 400 OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8)); 401 OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask); 402 } 403 404 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl, 405 u8 mask) 406 { 407 new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask); 408 409 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8)); 410 nh->ttl = new_ttl; 411 } 412 413 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key, 414 const struct ovs_key_ipv4 *key, 415 const struct ovs_key_ipv4 *mask) 416 { 417 struct iphdr *nh; 418 __be32 new_addr; 419 int err; 420 421 err = skb_ensure_writable(skb, skb_network_offset(skb) + 422 sizeof(struct iphdr)); 423 if (unlikely(err)) 424 return err; 425 426 nh = ip_hdr(skb); 427 428 /* Setting an IP addresses is typically only a side effect of 429 * matching on them in the current userspace implementation, so it 430 * makes sense to check if the value actually changed. 431 */ 432 if (mask->ipv4_src) { 433 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src); 434 435 if (unlikely(new_addr != nh->saddr)) { 436 set_ip_addr(skb, nh, &nh->saddr, new_addr); 437 flow_key->ipv4.addr.src = new_addr; 438 } 439 } 440 if (mask->ipv4_dst) { 441 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst); 442 443 if (unlikely(new_addr != nh->daddr)) { 444 set_ip_addr(skb, nh, &nh->daddr, new_addr); 445 flow_key->ipv4.addr.dst = new_addr; 446 } 447 } 448 if (mask->ipv4_tos) { 449 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos); 450 flow_key->ip.tos = nh->tos; 451 } 452 if (mask->ipv4_ttl) { 453 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl); 454 flow_key->ip.ttl = nh->ttl; 455 } 456 457 return 0; 458 } 459 460 static bool is_ipv6_mask_nonzero(const __be32 addr[4]) 461 { 462 return !!(addr[0] | addr[1] | addr[2] | addr[3]); 463 } 464 465 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key, 466 const struct ovs_key_ipv6 *key, 467 const struct ovs_key_ipv6 *mask) 468 { 469 struct ipv6hdr *nh; 470 int err; 471 472 err = skb_ensure_writable(skb, skb_network_offset(skb) + 473 sizeof(struct ipv6hdr)); 474 if (unlikely(err)) 475 return err; 476 477 nh = ipv6_hdr(skb); 478 479 /* Setting an IP addresses is typically only a side effect of 480 * matching on them in the current userspace implementation, so it 481 * makes sense to check if the value actually changed. 482 */ 483 if (is_ipv6_mask_nonzero(mask->ipv6_src)) { 484 __be32 *saddr = (__be32 *)&nh->saddr; 485 __be32 masked[4]; 486 487 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked); 488 489 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) { 490 set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked, 491 true); 492 memcpy(&flow_key->ipv6.addr.src, masked, 493 sizeof(flow_key->ipv6.addr.src)); 494 } 495 } 496 if (is_ipv6_mask_nonzero(mask->ipv6_dst)) { 497 unsigned int offset = 0; 498 int flags = IP6_FH_F_SKIP_RH; 499 bool recalc_csum = true; 500 __be32 *daddr = (__be32 *)&nh->daddr; 501 __be32 masked[4]; 502 503 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked); 504 505 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) { 506 if (ipv6_ext_hdr(nh->nexthdr)) 507 recalc_csum = (ipv6_find_hdr(skb, &offset, 508 NEXTHDR_ROUTING, 509 NULL, &flags) 510 != NEXTHDR_ROUTING); 511 512 set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked, 513 recalc_csum); 514 memcpy(&flow_key->ipv6.addr.dst, masked, 515 sizeof(flow_key->ipv6.addr.dst)); 516 } 517 } 518 if (mask->ipv6_tclass) { 519 ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass); 520 flow_key->ip.tos = ipv6_get_dsfield(nh); 521 } 522 if (mask->ipv6_label) { 523 set_ipv6_fl(nh, ntohl(key->ipv6_label), 524 ntohl(mask->ipv6_label)); 525 flow_key->ipv6.label = 526 *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL); 527 } 528 if (mask->ipv6_hlimit) { 529 OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit, 530 mask->ipv6_hlimit); 531 flow_key->ip.ttl = nh->hop_limit; 532 } 533 return 0; 534 } 535 536 /* Must follow skb_ensure_writable() since that can move the skb data. */ 537 static void set_tp_port(struct sk_buff *skb, __be16 *port, 538 __be16 new_port, __sum16 *check) 539 { 540 inet_proto_csum_replace2(check, skb, *port, new_port, false); 541 *port = new_port; 542 } 543 544 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key, 545 const struct ovs_key_udp *key, 546 const struct ovs_key_udp *mask) 547 { 548 struct udphdr *uh; 549 __be16 src, dst; 550 int err; 551 552 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 553 sizeof(struct udphdr)); 554 if (unlikely(err)) 555 return err; 556 557 uh = udp_hdr(skb); 558 /* Either of the masks is non-zero, so do not bother checking them. */ 559 src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src); 560 dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst); 561 562 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) { 563 if (likely(src != uh->source)) { 564 set_tp_port(skb, &uh->source, src, &uh->check); 565 flow_key->tp.src = src; 566 } 567 if (likely(dst != uh->dest)) { 568 set_tp_port(skb, &uh->dest, dst, &uh->check); 569 flow_key->tp.dst = dst; 570 } 571 572 if (unlikely(!uh->check)) 573 uh->check = CSUM_MANGLED_0; 574 } else { 575 uh->source = src; 576 uh->dest = dst; 577 flow_key->tp.src = src; 578 flow_key->tp.dst = dst; 579 } 580 581 skb_clear_hash(skb); 582 583 return 0; 584 } 585 586 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key, 587 const struct ovs_key_tcp *key, 588 const struct ovs_key_tcp *mask) 589 { 590 struct tcphdr *th; 591 __be16 src, dst; 592 int err; 593 594 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 595 sizeof(struct tcphdr)); 596 if (unlikely(err)) 597 return err; 598 599 th = tcp_hdr(skb); 600 src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src); 601 if (likely(src != th->source)) { 602 set_tp_port(skb, &th->source, src, &th->check); 603 flow_key->tp.src = src; 604 } 605 dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst); 606 if (likely(dst != th->dest)) { 607 set_tp_port(skb, &th->dest, dst, &th->check); 608 flow_key->tp.dst = dst; 609 } 610 skb_clear_hash(skb); 611 612 return 0; 613 } 614 615 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key, 616 const struct ovs_key_sctp *key, 617 const struct ovs_key_sctp *mask) 618 { 619 unsigned int sctphoff = skb_transport_offset(skb); 620 struct sctphdr *sh; 621 __le32 old_correct_csum, new_csum, old_csum; 622 int err; 623 624 err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr)); 625 if (unlikely(err)) 626 return err; 627 628 sh = sctp_hdr(skb); 629 old_csum = sh->checksum; 630 old_correct_csum = sctp_compute_cksum(skb, sctphoff); 631 632 sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src); 633 sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst); 634 635 new_csum = sctp_compute_cksum(skb, sctphoff); 636 637 /* Carry any checksum errors through. */ 638 sh->checksum = old_csum ^ old_correct_csum ^ new_csum; 639 640 skb_clear_hash(skb); 641 flow_key->tp.src = sh->source; 642 flow_key->tp.dst = sh->dest; 643 644 return 0; 645 } 646 647 static int ovs_vport_output(struct net *net, struct sock *sk, struct sk_buff *skb) 648 { 649 struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage); 650 struct vport *vport = data->vport; 651 652 if (skb_cow_head(skb, data->l2_len) < 0) { 653 kfree_skb(skb); 654 return -ENOMEM; 655 } 656 657 __skb_dst_copy(skb, data->dst); 658 *OVS_CB(skb) = data->cb; 659 skb->inner_protocol = data->inner_protocol; 660 skb->vlan_tci = data->vlan_tci; 661 skb->vlan_proto = data->vlan_proto; 662 663 /* Reconstruct the MAC header. */ 664 skb_push(skb, data->l2_len); 665 memcpy(skb->data, &data->l2_data, data->l2_len); 666 skb_postpush_rcsum(skb, skb->data, data->l2_len); 667 skb_reset_mac_header(skb); 668 669 ovs_vport_send(vport, skb); 670 return 0; 671 } 672 673 static unsigned int 674 ovs_dst_get_mtu(const struct dst_entry *dst) 675 { 676 return dst->dev->mtu; 677 } 678 679 static struct dst_ops ovs_dst_ops = { 680 .family = AF_UNSPEC, 681 .mtu = ovs_dst_get_mtu, 682 }; 683 684 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is 685 * ovs_vport_output(), which is called once per fragmented packet. 686 */ 687 static void prepare_frag(struct vport *vport, struct sk_buff *skb) 688 { 689 unsigned int hlen = skb_network_offset(skb); 690 struct ovs_frag_data *data; 691 692 data = this_cpu_ptr(&ovs_frag_data_storage); 693 data->dst = skb->_skb_refdst; 694 data->vport = vport; 695 data->cb = *OVS_CB(skb); 696 data->inner_protocol = skb->inner_protocol; 697 data->vlan_tci = skb->vlan_tci; 698 data->vlan_proto = skb->vlan_proto; 699 data->l2_len = hlen; 700 memcpy(&data->l2_data, skb->data, hlen); 701 702 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 703 skb_pull(skb, hlen); 704 } 705 706 static void ovs_fragment(struct net *net, struct vport *vport, 707 struct sk_buff *skb, u16 mru, __be16 ethertype) 708 { 709 if (skb_network_offset(skb) > MAX_L2_LEN) { 710 OVS_NLERR(1, "L2 header too long to fragment"); 711 goto err; 712 } 713 714 if (ethertype == htons(ETH_P_IP)) { 715 struct dst_entry ovs_dst; 716 unsigned long orig_dst; 717 718 prepare_frag(vport, skb); 719 dst_init(&ovs_dst, &ovs_dst_ops, NULL, 1, 720 DST_OBSOLETE_NONE, DST_NOCOUNT); 721 ovs_dst.dev = vport->dev; 722 723 orig_dst = skb->_skb_refdst; 724 skb_dst_set_noref(skb, &ovs_dst); 725 IPCB(skb)->frag_max_size = mru; 726 727 ip_do_fragment(net, skb->sk, skb, ovs_vport_output); 728 refdst_drop(orig_dst); 729 } else if (ethertype == htons(ETH_P_IPV6)) { 730 const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops(); 731 unsigned long orig_dst; 732 struct rt6_info ovs_rt; 733 734 if (!v6ops) { 735 goto err; 736 } 737 738 prepare_frag(vport, skb); 739 memset(&ovs_rt, 0, sizeof(ovs_rt)); 740 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1, 741 DST_OBSOLETE_NONE, DST_NOCOUNT); 742 ovs_rt.dst.dev = vport->dev; 743 744 orig_dst = skb->_skb_refdst; 745 skb_dst_set_noref(skb, &ovs_rt.dst); 746 IP6CB(skb)->frag_max_size = mru; 747 748 v6ops->fragment(net, skb->sk, skb, ovs_vport_output); 749 refdst_drop(orig_dst); 750 } else { 751 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.", 752 ovs_vport_name(vport), ntohs(ethertype), mru, 753 vport->dev->mtu); 754 goto err; 755 } 756 757 return; 758 err: 759 kfree_skb(skb); 760 } 761 762 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port, 763 struct sw_flow_key *key) 764 { 765 struct vport *vport = ovs_vport_rcu(dp, out_port); 766 767 if (likely(vport)) { 768 u16 mru = OVS_CB(skb)->mru; 769 u32 cutlen = OVS_CB(skb)->cutlen; 770 771 if (unlikely(cutlen > 0)) { 772 if (skb->len - cutlen > ETH_HLEN) 773 pskb_trim(skb, skb->len - cutlen); 774 else 775 pskb_trim(skb, ETH_HLEN); 776 } 777 778 if (likely(!mru || (skb->len <= mru + ETH_HLEN))) { 779 ovs_vport_send(vport, skb); 780 } else if (mru <= vport->dev->mtu) { 781 struct net *net = read_pnet(&dp->net); 782 __be16 ethertype = key->eth.type; 783 784 if (!is_flow_key_valid(key)) { 785 if (eth_p_mpls(skb->protocol)) 786 ethertype = skb->inner_protocol; 787 else 788 ethertype = vlan_get_protocol(skb); 789 } 790 791 ovs_fragment(net, vport, skb, mru, ethertype); 792 } else { 793 kfree_skb(skb); 794 } 795 } else { 796 kfree_skb(skb); 797 } 798 } 799 800 static int output_userspace(struct datapath *dp, struct sk_buff *skb, 801 struct sw_flow_key *key, const struct nlattr *attr, 802 const struct nlattr *actions, int actions_len, 803 uint32_t cutlen) 804 { 805 struct dp_upcall_info upcall; 806 const struct nlattr *a; 807 int rem; 808 809 memset(&upcall, 0, sizeof(upcall)); 810 upcall.cmd = OVS_PACKET_CMD_ACTION; 811 upcall.mru = OVS_CB(skb)->mru; 812 813 for (a = nla_data(attr), rem = nla_len(attr); rem > 0; 814 a = nla_next(a, &rem)) { 815 switch (nla_type(a)) { 816 case OVS_USERSPACE_ATTR_USERDATA: 817 upcall.userdata = a; 818 break; 819 820 case OVS_USERSPACE_ATTR_PID: 821 upcall.portid = nla_get_u32(a); 822 break; 823 824 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: { 825 /* Get out tunnel info. */ 826 struct vport *vport; 827 828 vport = ovs_vport_rcu(dp, nla_get_u32(a)); 829 if (vport) { 830 int err; 831 832 err = dev_fill_metadata_dst(vport->dev, skb); 833 if (!err) 834 upcall.egress_tun_info = skb_tunnel_info(skb); 835 } 836 837 break; 838 } 839 840 case OVS_USERSPACE_ATTR_ACTIONS: { 841 /* Include actions. */ 842 upcall.actions = actions; 843 upcall.actions_len = actions_len; 844 break; 845 } 846 847 } /* End of switch. */ 848 } 849 850 return ovs_dp_upcall(dp, skb, key, &upcall, cutlen); 851 } 852 853 static int sample(struct datapath *dp, struct sk_buff *skb, 854 struct sw_flow_key *key, const struct nlattr *attr, 855 const struct nlattr *actions, int actions_len) 856 { 857 const struct nlattr *acts_list = NULL; 858 const struct nlattr *a; 859 int rem; 860 u32 cutlen = 0; 861 862 for (a = nla_data(attr), rem = nla_len(attr); rem > 0; 863 a = nla_next(a, &rem)) { 864 u32 probability; 865 866 switch (nla_type(a)) { 867 case OVS_SAMPLE_ATTR_PROBABILITY: 868 probability = nla_get_u32(a); 869 if (!probability || prandom_u32() > probability) 870 return 0; 871 break; 872 873 case OVS_SAMPLE_ATTR_ACTIONS: 874 acts_list = a; 875 break; 876 } 877 } 878 879 rem = nla_len(acts_list); 880 a = nla_data(acts_list); 881 882 /* Actions list is empty, do nothing */ 883 if (unlikely(!rem)) 884 return 0; 885 886 /* The only known usage of sample action is having a single user-space 887 * action, or having a truncate action followed by a single user-space 888 * action. Treat this usage as a special case. 889 * The output_userspace() should clone the skb to be sent to the 890 * user space. This skb will be consumed by its caller. 891 */ 892 if (unlikely(nla_type(a) == OVS_ACTION_ATTR_TRUNC)) { 893 struct ovs_action_trunc *trunc = nla_data(a); 894 895 if (skb->len > trunc->max_len) 896 cutlen = skb->len - trunc->max_len; 897 898 a = nla_next(a, &rem); 899 } 900 901 if (likely(nla_type(a) == OVS_ACTION_ATTR_USERSPACE && 902 nla_is_last(a, rem))) 903 return output_userspace(dp, skb, key, a, actions, 904 actions_len, cutlen); 905 906 skb = skb_clone(skb, GFP_ATOMIC); 907 if (!skb) 908 /* Skip the sample action when out of memory. */ 909 return 0; 910 911 if (!add_deferred_actions(skb, key, a)) { 912 if (net_ratelimit()) 913 pr_warn("%s: deferred actions limit reached, dropping sample action\n", 914 ovs_dp_name(dp)); 915 916 kfree_skb(skb); 917 } 918 return 0; 919 } 920 921 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key, 922 const struct nlattr *attr) 923 { 924 struct ovs_action_hash *hash_act = nla_data(attr); 925 u32 hash = 0; 926 927 /* OVS_HASH_ALG_L4 is the only possible hash algorithm. */ 928 hash = skb_get_hash(skb); 929 hash = jhash_1word(hash, hash_act->hash_basis); 930 if (!hash) 931 hash = 0x1; 932 933 key->ovs_flow_hash = hash; 934 } 935 936 static int execute_set_action(struct sk_buff *skb, 937 struct sw_flow_key *flow_key, 938 const struct nlattr *a) 939 { 940 /* Only tunnel set execution is supported without a mask. */ 941 if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) { 942 struct ovs_tunnel_info *tun = nla_data(a); 943 944 skb_dst_drop(skb); 945 dst_hold((struct dst_entry *)tun->tun_dst); 946 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst); 947 return 0; 948 } 949 950 return -EINVAL; 951 } 952 953 /* Mask is at the midpoint of the data. */ 954 #define get_mask(a, type) ((const type)nla_data(a) + 1) 955 956 static int execute_masked_set_action(struct sk_buff *skb, 957 struct sw_flow_key *flow_key, 958 const struct nlattr *a) 959 { 960 int err = 0; 961 962 switch (nla_type(a)) { 963 case OVS_KEY_ATTR_PRIORITY: 964 OVS_SET_MASKED(skb->priority, nla_get_u32(a), 965 *get_mask(a, u32 *)); 966 flow_key->phy.priority = skb->priority; 967 break; 968 969 case OVS_KEY_ATTR_SKB_MARK: 970 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *)); 971 flow_key->phy.skb_mark = skb->mark; 972 break; 973 974 case OVS_KEY_ATTR_TUNNEL_INFO: 975 /* Masked data not supported for tunnel. */ 976 err = -EINVAL; 977 break; 978 979 case OVS_KEY_ATTR_ETHERNET: 980 err = set_eth_addr(skb, flow_key, nla_data(a), 981 get_mask(a, struct ovs_key_ethernet *)); 982 break; 983 984 case OVS_KEY_ATTR_IPV4: 985 err = set_ipv4(skb, flow_key, nla_data(a), 986 get_mask(a, struct ovs_key_ipv4 *)); 987 break; 988 989 case OVS_KEY_ATTR_IPV6: 990 err = set_ipv6(skb, flow_key, nla_data(a), 991 get_mask(a, struct ovs_key_ipv6 *)); 992 break; 993 994 case OVS_KEY_ATTR_TCP: 995 err = set_tcp(skb, flow_key, nla_data(a), 996 get_mask(a, struct ovs_key_tcp *)); 997 break; 998 999 case OVS_KEY_ATTR_UDP: 1000 err = set_udp(skb, flow_key, nla_data(a), 1001 get_mask(a, struct ovs_key_udp *)); 1002 break; 1003 1004 case OVS_KEY_ATTR_SCTP: 1005 err = set_sctp(skb, flow_key, nla_data(a), 1006 get_mask(a, struct ovs_key_sctp *)); 1007 break; 1008 1009 case OVS_KEY_ATTR_MPLS: 1010 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a, 1011 __be32 *)); 1012 break; 1013 1014 case OVS_KEY_ATTR_CT_STATE: 1015 case OVS_KEY_ATTR_CT_ZONE: 1016 case OVS_KEY_ATTR_CT_MARK: 1017 case OVS_KEY_ATTR_CT_LABELS: 1018 err = -EINVAL; 1019 break; 1020 } 1021 1022 return err; 1023 } 1024 1025 static int execute_recirc(struct datapath *dp, struct sk_buff *skb, 1026 struct sw_flow_key *key, 1027 const struct nlattr *a, int rem) 1028 { 1029 struct deferred_action *da; 1030 int level; 1031 1032 if (!is_flow_key_valid(key)) { 1033 int err; 1034 1035 err = ovs_flow_key_update(skb, key); 1036 if (err) 1037 return err; 1038 } 1039 BUG_ON(!is_flow_key_valid(key)); 1040 1041 if (!nla_is_last(a, rem)) { 1042 /* Recirc action is the not the last action 1043 * of the action list, need to clone the skb. 1044 */ 1045 skb = skb_clone(skb, GFP_ATOMIC); 1046 1047 /* Skip the recirc action when out of memory, but 1048 * continue on with the rest of the action list. 1049 */ 1050 if (!skb) 1051 return 0; 1052 } 1053 1054 level = this_cpu_read(exec_actions_level); 1055 if (level <= OVS_DEFERRED_ACTION_THRESHOLD) { 1056 struct recirc_keys *rks = this_cpu_ptr(recirc_keys); 1057 struct sw_flow_key *recirc_key = &rks->key[level - 1]; 1058 1059 *recirc_key = *key; 1060 recirc_key->recirc_id = nla_get_u32(a); 1061 ovs_dp_process_packet(skb, recirc_key); 1062 1063 return 0; 1064 } 1065 1066 da = add_deferred_actions(skb, key, NULL); 1067 if (da) { 1068 da->pkt_key.recirc_id = nla_get_u32(a); 1069 } else { 1070 kfree_skb(skb); 1071 1072 if (net_ratelimit()) 1073 pr_warn("%s: deferred action limit reached, drop recirc action\n", 1074 ovs_dp_name(dp)); 1075 } 1076 1077 return 0; 1078 } 1079 1080 /* Execute a list of actions against 'skb'. */ 1081 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 1082 struct sw_flow_key *key, 1083 const struct nlattr *attr, int len) 1084 { 1085 /* Every output action needs a separate clone of 'skb', but the common 1086 * case is just a single output action, so that doing a clone and 1087 * then freeing the original skbuff is wasteful. So the following code 1088 * is slightly obscure just to avoid that. 1089 */ 1090 int prev_port = -1; 1091 const struct nlattr *a; 1092 int rem; 1093 1094 for (a = attr, rem = len; rem > 0; 1095 a = nla_next(a, &rem)) { 1096 int err = 0; 1097 1098 if (unlikely(prev_port != -1)) { 1099 struct sk_buff *out_skb = skb_clone(skb, GFP_ATOMIC); 1100 1101 if (out_skb) 1102 do_output(dp, out_skb, prev_port, key); 1103 1104 OVS_CB(skb)->cutlen = 0; 1105 prev_port = -1; 1106 } 1107 1108 switch (nla_type(a)) { 1109 case OVS_ACTION_ATTR_OUTPUT: 1110 prev_port = nla_get_u32(a); 1111 break; 1112 1113 case OVS_ACTION_ATTR_TRUNC: { 1114 struct ovs_action_trunc *trunc = nla_data(a); 1115 1116 if (skb->len > trunc->max_len) 1117 OVS_CB(skb)->cutlen = skb->len - trunc->max_len; 1118 break; 1119 } 1120 1121 case OVS_ACTION_ATTR_USERSPACE: 1122 output_userspace(dp, skb, key, a, attr, 1123 len, OVS_CB(skb)->cutlen); 1124 OVS_CB(skb)->cutlen = 0; 1125 break; 1126 1127 case OVS_ACTION_ATTR_HASH: 1128 execute_hash(skb, key, a); 1129 break; 1130 1131 case OVS_ACTION_ATTR_PUSH_MPLS: 1132 err = push_mpls(skb, key, nla_data(a)); 1133 break; 1134 1135 case OVS_ACTION_ATTR_POP_MPLS: 1136 err = pop_mpls(skb, key, nla_get_be16(a)); 1137 break; 1138 1139 case OVS_ACTION_ATTR_PUSH_VLAN: 1140 err = push_vlan(skb, key, nla_data(a)); 1141 break; 1142 1143 case OVS_ACTION_ATTR_POP_VLAN: 1144 err = pop_vlan(skb, key); 1145 break; 1146 1147 case OVS_ACTION_ATTR_RECIRC: 1148 err = execute_recirc(dp, skb, key, a, rem); 1149 if (nla_is_last(a, rem)) { 1150 /* If this is the last action, the skb has 1151 * been consumed or freed. 1152 * Return immediately. 1153 */ 1154 return err; 1155 } 1156 break; 1157 1158 case OVS_ACTION_ATTR_SET: 1159 err = execute_set_action(skb, key, nla_data(a)); 1160 break; 1161 1162 case OVS_ACTION_ATTR_SET_MASKED: 1163 case OVS_ACTION_ATTR_SET_TO_MASKED: 1164 err = execute_masked_set_action(skb, key, nla_data(a)); 1165 break; 1166 1167 case OVS_ACTION_ATTR_SAMPLE: 1168 err = sample(dp, skb, key, a, attr, len); 1169 break; 1170 1171 case OVS_ACTION_ATTR_CT: 1172 if (!is_flow_key_valid(key)) { 1173 err = ovs_flow_key_update(skb, key); 1174 if (err) 1175 return err; 1176 } 1177 1178 err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key, 1179 nla_data(a)); 1180 1181 /* Hide stolen IP fragments from user space. */ 1182 if (err) 1183 return err == -EINPROGRESS ? 0 : err; 1184 break; 1185 } 1186 1187 if (unlikely(err)) { 1188 kfree_skb(skb); 1189 return err; 1190 } 1191 } 1192 1193 if (prev_port != -1) 1194 do_output(dp, skb, prev_port, key); 1195 else 1196 consume_skb(skb); 1197 1198 return 0; 1199 } 1200 1201 static void process_deferred_actions(struct datapath *dp) 1202 { 1203 struct action_fifo *fifo = this_cpu_ptr(action_fifos); 1204 1205 /* Do not touch the FIFO in case there is no deferred actions. */ 1206 if (action_fifo_is_empty(fifo)) 1207 return; 1208 1209 /* Finishing executing all deferred actions. */ 1210 do { 1211 struct deferred_action *da = action_fifo_get(fifo); 1212 struct sk_buff *skb = da->skb; 1213 struct sw_flow_key *key = &da->pkt_key; 1214 const struct nlattr *actions = da->actions; 1215 1216 if (actions) 1217 do_execute_actions(dp, skb, key, actions, 1218 nla_len(actions)); 1219 else 1220 ovs_dp_process_packet(skb, key); 1221 } while (!action_fifo_is_empty(fifo)); 1222 1223 /* Reset FIFO for the next packet. */ 1224 action_fifo_init(fifo); 1225 } 1226 1227 /* Execute a list of actions against 'skb'. */ 1228 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, 1229 const struct sw_flow_actions *acts, 1230 struct sw_flow_key *key) 1231 { 1232 int err, level; 1233 1234 level = __this_cpu_inc_return(exec_actions_level); 1235 if (unlikely(level > OVS_RECURSION_LIMIT)) { 1236 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n", 1237 ovs_dp_name(dp)); 1238 kfree_skb(skb); 1239 err = -ENETDOWN; 1240 goto out; 1241 } 1242 1243 err = do_execute_actions(dp, skb, key, 1244 acts->actions, acts->actions_len); 1245 1246 if (level == 1) 1247 process_deferred_actions(dp); 1248 1249 out: 1250 __this_cpu_dec(exec_actions_level); 1251 return err; 1252 } 1253 1254 int action_fifos_init(void) 1255 { 1256 action_fifos = alloc_percpu(struct action_fifo); 1257 if (!action_fifos) 1258 return -ENOMEM; 1259 1260 recirc_keys = alloc_percpu(struct recirc_keys); 1261 if (!recirc_keys) { 1262 free_percpu(action_fifos); 1263 return -ENOMEM; 1264 } 1265 1266 return 0; 1267 } 1268 1269 void action_fifos_exit(void) 1270 { 1271 free_percpu(action_fifos); 1272 free_percpu(recirc_keys); 1273 } 1274