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