net/openvswitch/actions.c

   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/sctp.h>
  26 #include <linux/tcp.h>
  27 #include <linux/udp.h>
  28 #include <linux/in6.h>
  29 #include <linux/if_arp.h>
  30 #include <linux/if_vlan.h>
  31
  32 #include <net/ip.h>
  33 #include <net/ipv6.h>
  34 #include <net/checksum.h>
  35 #include <net/dsfield.h>
  36 #include <net/mpls.h>
  37 #include <net/sctp/checksum.h>
  38
  39 #include "datapath.h"
  40 #include "flow.h"
  41 #include "vport.h"
  42
  43 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
  44                               struct sw_flow_key *key,
  45                               const struct nlattr *attr, int len);
  46
  47 struct deferred_action {
  48         struct sk_buff *skb;
  49         const struct nlattr *actions;
  50
  51         /* Store pkt_key clone when creating deferred action. */
  52         struct sw_flow_key pkt_key;
  53 };
  54
  55 #define DEFERRED_ACTION_FIFO_SIZE 10
  56 struct action_fifo {
  57         int head;
  58         int tail;
  59         /* Deferred action fifo queue storage. */
  60         struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
  61 };
  62
  63 static struct action_fifo __percpu *action_fifos;
  64 static DEFINE_PER_CPU(int, exec_actions_level);
  65
  66 static void action_fifo_init(struct action_fifo *fifo)
  67 {
  68         fifo->head = 0;
  69         fifo->tail = 0;
  70 }
  71
  72 static bool action_fifo_is_empty(const struct action_fifo *fifo)
  73 {
  74         return (fifo->head == fifo->tail);
  75 }
  76
  77 static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
  78 {
  79         if (action_fifo_is_empty(fifo))
  80                 return NULL;
  81
  82         return &fifo->fifo[fifo->tail++];
  83 }
  84
  85 static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
  86 {
  87         if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
  88                 return NULL;
  89
  90         return &fifo->fifo[fifo->head++];
  91 }
  92
  93 /* Return true if fifo is not full */
  94 static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
  95                                                     const struct sw_flow_key *key,
  96                                                     const struct nlattr *attr)
  97 {
  98         struct action_fifo *fifo;
  99         struct deferred_action *da;
 100
 101         fifo = this_cpu_ptr(action_fifos);
 102         da = action_fifo_put(fifo);
 103         if (da) {
 104                 da->skb = skb;
 105                 da->actions = attr;
 106                 da->pkt_key = *key;
 107         }
 108
 109         return da;
 110 }
 111
 112 static void invalidate_flow_key(struct sw_flow_key *key)
 113 {
 114         key->eth.type = htons(0);
 115 }
 116
 117 static bool is_flow_key_valid(const struct sw_flow_key *key)
 118 {
 119         return !!key->eth.type;
 120 }
 121
 122 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 123                      const struct ovs_action_push_mpls *mpls)
 124 {
 125         __be32 *new_mpls_lse;
 126         struct ethhdr *hdr;
 127
 128         /* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */
 129         if (skb->encapsulation)
 130                 return -ENOTSUPP;
 131
 132         if (skb_cow_head(skb, MPLS_HLEN) < 0)
 133                 return -ENOMEM;
 134
 135         skb_push(skb, MPLS_HLEN);
 136         memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb),
 137                 skb->mac_len);
 138         skb_reset_mac_header(skb);
 139
 140         new_mpls_lse = (__be32 *)skb_mpls_header(skb);
 141         *new_mpls_lse = mpls->mpls_lse;
 142
 143         if (skb->ip_summed == CHECKSUM_COMPLETE)
 144                 skb->csum = csum_add(skb->csum, csum_partial(new_mpls_lse,
 145                                                              MPLS_HLEN, 0));
 146
 147         hdr = eth_hdr(skb);
 148         hdr->h_proto = mpls->mpls_ethertype;
 149
 150         if (!skb->inner_protocol)
 151                 skb_set_inner_protocol(skb, skb->protocol);
 152         skb->protocol = mpls->mpls_ethertype;
 153
 154         invalidate_flow_key(key);
 155         return 0;
 156 }
 157
 158 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 159                     const __be16 ethertype)
 160 {
 161         struct ethhdr *hdr;
 162         int err;
 163
 164         err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
 165         if (unlikely(err))
 166                 return err;
 167
 168         skb_postpull_rcsum(skb, skb_mpls_header(skb), MPLS_HLEN);
 169
 170         memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb),
 171                 skb->mac_len);
 172
 173         __skb_pull(skb, MPLS_HLEN);
 174         skb_reset_mac_header(skb);
 175
 176         /* skb_mpls_header() is used to locate the ethertype
 177          * field correctly in the presence of VLAN tags.
 178          */
 179         hdr = (struct ethhdr *)(skb_mpls_header(skb) - ETH_HLEN);
 180         hdr->h_proto = ethertype;
 181         if (eth_p_mpls(skb->protocol))
 182                 skb->protocol = ethertype;
 183
 184         invalidate_flow_key(key);
 185         return 0;
 186 }
 187
 188 /* 'KEY' must not have any bits set outside of the 'MASK' */
 189 #define MASKED(OLD, KEY, MASK) ((KEY) | ((OLD) & ~(MASK)))
 190 #define SET_MASKED(OLD, KEY, MASK) ((OLD) = MASKED(OLD, KEY, MASK))
 191
 192 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
 193                     const __be32 *mpls_lse, const __be32 *mask)
 194 {
 195         __be32 *stack;
 196         __be32 lse;
 197         int err;
 198
 199         err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
 200         if (unlikely(err))
 201                 return err;
 202
 203         stack = (__be32 *)skb_mpls_header(skb);
 204         lse = MASKED(*stack, *mpls_lse, *mask);
 205         if (skb->ip_summed == CHECKSUM_COMPLETE) {
 206                 __be32 diff[] = { ~(*stack), lse };
 207
 208                 skb->csum = ~csum_partial((char *)diff, sizeof(diff),
 209                                           ~skb->csum);
 210         }
 211
 212         *stack = lse;
 213         flow_key->mpls.top_lse = lse;
 214         return 0;
 215 }
 216
 217 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 218 {
 219         int err;
 220
 221         err = skb_vlan_pop(skb);
 222         if (skb_vlan_tag_present(skb))
 223                 invalidate_flow_key(key);
 224         else
 225                 key->eth.tci = 0;
 226         return err;
 227 }
 228
 229 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
 230                      const struct ovs_action_push_vlan *vlan)
 231 {
 232         if (skb_vlan_tag_present(skb))
 233                 invalidate_flow_key(key);
 234         else
 235                 key->eth.tci = vlan->vlan_tci;
 236         return skb_vlan_push(skb, vlan->vlan_tpid,
 237                              ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
 238 }
 239
 240 /* 'src' is already properly masked. */
 241 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
 242 {
 243         u16 *dst = (u16 *)dst_;
 244         const u16 *src = (const u16 *)src_;
 245         const u16 *mask = (const u16 *)mask_;
 246
 247         SET_MASKED(dst[0], src[0], mask[0]);
 248         SET_MASKED(dst[1], src[1], mask[1]);
 249         SET_MASKED(dst[2], src[2], mask[2]);
 250 }
 251
 252 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
 253                         const struct ovs_key_ethernet *key,
 254                         const struct ovs_key_ethernet *mask)
 255 {
 256         int err;
 257
 258         err = skb_ensure_writable(skb, ETH_HLEN);
 259         if (unlikely(err))
 260                 return err;
 261
 262         skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 263
 264         ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
 265                                mask->eth_src);
 266         ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
 267                                mask->eth_dst);
 268
 269         ovs_skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
 270
 271         ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
 272         ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
 273         return 0;
 274 }
 275
 276 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
 277                         __be32 *addr, __be32 new_addr)
 278 {
 279         int transport_len = skb->len - skb_transport_offset(skb);
 280
 281         if (nh->protocol == IPPROTO_TCP) {
 282                 if (likely(transport_len >= sizeof(struct tcphdr)))
 283                         inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
 284                                                  *addr, new_addr, 1);
 285         } else if (nh->protocol == IPPROTO_UDP) {
 286                 if (likely(transport_len >= sizeof(struct udphdr))) {
 287                         struct udphdr *uh = udp_hdr(skb);
 288
 289                         if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 290                                 inet_proto_csum_replace4(&uh->check, skb,
 291                                                          *addr, new_addr, 1);
 292                                 if (!uh->check)
 293                                         uh->check = CSUM_MANGLED_0;
 294                         }
 295                 }
 296         }
 297
 298         csum_replace4(&nh->check, *addr, new_addr);
 299         skb_clear_hash(skb);
 300         *addr = new_addr;
 301 }
 302
 303 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
 304                                  __be32 addr[4], const __be32 new_addr[4])
 305 {
 306         int transport_len = skb->len - skb_transport_offset(skb);
 307
 308         if (l4_proto == NEXTHDR_TCP) {
 309                 if (likely(transport_len >= sizeof(struct tcphdr)))
 310                         inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
 311                                                   addr, new_addr, 1);
 312         } else if (l4_proto == NEXTHDR_UDP) {
 313                 if (likely(transport_len >= sizeof(struct udphdr))) {
 314                         struct udphdr *uh = udp_hdr(skb);
 315
 316                         if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 317                                 inet_proto_csum_replace16(&uh->check, skb,
 318                                                           addr, new_addr, 1);
 319                                 if (!uh->check)
 320                                         uh->check = CSUM_MANGLED_0;
 321                         }
 322                 }
 323         } else if (l4_proto == NEXTHDR_ICMP) {
 324                 if (likely(transport_len >= sizeof(struct icmp6hdr)))
 325                         inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
 326                                                   skb, addr, new_addr, 1);
 327         }
 328 }
 329
 330 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
 331                            const __be32 mask[4], __be32 masked[4])
 332 {
 333         masked[0] = MASKED(old[0], addr[0], mask[0]);
 334         masked[1] = MASKED(old[1], addr[1], mask[1]);
 335         masked[2] = MASKED(old[2], addr[2], mask[2]);
 336         masked[3] = MASKED(old[3], addr[3], mask[3]);
 337 }
 338
 339 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
 340                           __be32 addr[4], const __be32 new_addr[4],
 341                           bool recalculate_csum)
 342 {
 343         if (recalculate_csum)
 344                 update_ipv6_checksum(skb, l4_proto, addr, new_addr);
 345
 346         skb_clear_hash(skb);
 347         memcpy(addr, new_addr, sizeof(__be32[4]));
 348 }
 349
 350 static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask)
 351 {
 352         /* Bits 21-24 are always unmasked, so this retains their values. */
 353         SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16));
 354         SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8));
 355         SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask);
 356 }
 357
 358 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
 359                        u8 mask)
 360 {
 361         new_ttl = MASKED(nh->ttl, new_ttl, mask);
 362
 363         csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
 364         nh->ttl = new_ttl;
 365 }
 366
 367 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
 368                     const struct ovs_key_ipv4 *key,
 369                     const struct ovs_key_ipv4 *mask)
 370 {
 371         struct iphdr *nh;
 372         __be32 new_addr;
 373         int err;
 374
 375         err = skb_ensure_writable(skb, skb_network_offset(skb) +
 376                                   sizeof(struct iphdr));
 377         if (unlikely(err))
 378                 return err;
 379
 380         nh = ip_hdr(skb);
 381
 382         /* Setting an IP addresses is typically only a side effect of
 383          * matching on them in the current userspace implementation, so it
 384          * makes sense to check if the value actually changed.
 385          */
 386         if (mask->ipv4_src) {
 387                 new_addr = MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
 388
 389                 if (unlikely(new_addr != nh->saddr)) {
 390                         set_ip_addr(skb, nh, &nh->saddr, new_addr);
 391                         flow_key->ipv4.addr.src = new_addr;
 392                 }
 393         }
 394         if (mask->ipv4_dst) {
 395                 new_addr = MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
 396
 397                 if (unlikely(new_addr != nh->daddr)) {
 398                         set_ip_addr(skb, nh, &nh->daddr, new_addr);
 399                         flow_key->ipv4.addr.dst = new_addr;
 400                 }
 401         }
 402         if (mask->ipv4_tos) {
 403                 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
 404                 flow_key->ip.tos = nh->tos;
 405         }
 406         if (mask->ipv4_ttl) {
 407                 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
 408                 flow_key->ip.ttl = nh->ttl;
 409         }
 410
 411         return 0;
 412 }
 413
 414 static bool is_ipv6_mask_nonzero(const __be32 addr[4])
 415 {
 416         return !!(addr[0] | addr[1] | addr[2] | addr[3]);
 417 }
 418
 419 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
 420                     const struct ovs_key_ipv6 *key,
 421                     const struct ovs_key_ipv6 *mask)
 422 {
 423         struct ipv6hdr *nh;
 424         int err;
 425
 426         err = skb_ensure_writable(skb, skb_network_offset(skb) +
 427                                   sizeof(struct ipv6hdr));
 428         if (unlikely(err))
 429                 return err;
 430
 431         nh = ipv6_hdr(skb);
 432
 433         /* Setting an IP addresses is typically only a side effect of
 434          * matching on them in the current userspace implementation, so it
 435          * makes sense to check if the value actually changed.
 436          */
 437         if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
 438                 __be32 *saddr = (__be32 *)&nh->saddr;
 439                 __be32 masked[4];
 440
 441                 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
 442
 443                 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
 444                         set_ipv6_addr(skb, key->ipv6_proto, saddr, masked,
 445                                       true);
 446                         memcpy(&flow_key->ipv6.addr.src, masked,
 447                                sizeof(flow_key->ipv6.addr.src));
 448                 }
 449         }
 450         if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
 451                 unsigned int offset = 0;
 452                 int flags = IP6_FH_F_SKIP_RH;
 453                 bool recalc_csum = true;
 454                 __be32 *daddr = (__be32 *)&nh->daddr;
 455                 __be32 masked[4];
 456
 457                 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
 458
 459                 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
 460                         if (ipv6_ext_hdr(nh->nexthdr))
 461                                 recalc_csum = (ipv6_find_hdr(skb, &offset,
 462                                                              NEXTHDR_ROUTING,
 463                                                              NULL, &flags)
 464                                                != NEXTHDR_ROUTING);
 465
 466                         set_ipv6_addr(skb, key->ipv6_proto, daddr, masked,
 467                                       recalc_csum);
 468                         memcpy(&flow_key->ipv6.addr.dst, masked,
 469                                sizeof(flow_key->ipv6.addr.dst));
 470                 }
 471         }
 472         if (mask->ipv6_tclass) {
 473                 ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass);
 474                 flow_key->ip.tos = ipv6_get_dsfield(nh);
 475         }
 476         if (mask->ipv6_label) {
 477                 set_ipv6_fl(nh, ntohl(key->ipv6_label),
 478                             ntohl(mask->ipv6_label));
 479                 flow_key->ipv6.label =
 480                     *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 481         }
 482         if (mask->ipv6_hlimit) {
 483                 SET_MASKED(nh->hop_limit, key->ipv6_hlimit, mask->ipv6_hlimit);
 484                 flow_key->ip.ttl = nh->hop_limit;
 485         }
 486         return 0;
 487 }
 488
 489 /* Must follow skb_ensure_writable() since that can move the skb data. */
 490 static void set_tp_port(struct sk_buff *skb, __be16 *port,
 491                         __be16 new_port, __sum16 *check)
 492 {
 493         inet_proto_csum_replace2(check, skb, *port, new_port, 0);
 494         *port = new_port;
 495 }
 496
 497 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 498                    const struct ovs_key_udp *key,
 499                    const struct ovs_key_udp *mask)
 500 {
 501         struct udphdr *uh;
 502         __be16 src, dst;
 503         int err;
 504
 505         err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 506                                   sizeof(struct udphdr));
 507         if (unlikely(err))
 508                 return err;
 509
 510         uh = udp_hdr(skb);
 511         /* Either of the masks is non-zero, so do not bother checking them. */
 512         src = MASKED(uh->source, key->udp_src, mask->udp_src);
 513         dst = MASKED(uh->dest, key->udp_dst, mask->udp_dst);
 514
 515         if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
 516                 if (likely(src != uh->source)) {
 517                         set_tp_port(skb, &uh->source, src, &uh->check);
 518                         flow_key->tp.src = src;
 519                 }
 520                 if (likely(dst != uh->dest)) {
 521                         set_tp_port(skb, &uh->dest, dst, &uh->check);
 522                         flow_key->tp.dst = dst;
 523                 }
 524
 525                 if (unlikely(!uh->check))
 526                         uh->check = CSUM_MANGLED_0;
 527         } else {
 528                 uh->source = src;
 529                 uh->dest = dst;
 530                 flow_key->tp.src = src;
 531                 flow_key->tp.dst = dst;
 532         }
 533
 534         skb_clear_hash(skb);
 535
 536         return 0;
 537 }
 538
 539 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 540                    const struct ovs_key_tcp *key,
 541                    const struct ovs_key_tcp *mask)
 542 {
 543         struct tcphdr *th;
 544         __be16 src, dst;
 545         int err;
 546
 547         err = skb_ensure_writable(skb, skb_transport_offset(skb) +
 548                                   sizeof(struct tcphdr));
 549         if (unlikely(err))
 550                 return err;
 551
 552         th = tcp_hdr(skb);
 553         src = MASKED(th->source, key->tcp_src, mask->tcp_src);
 554         if (likely(src != th->source)) {
 555                 set_tp_port(skb, &th->source, src, &th->check);
 556                 flow_key->tp.src = src;
 557         }
 558         dst = MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
 559         if (likely(dst != th->dest)) {
 560                 set_tp_port(skb, &th->dest, dst, &th->check);
 561                 flow_key->tp.dst = dst;
 562         }
 563         skb_clear_hash(skb);
 564
 565         return 0;
 566 }
 567
 568 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
 569                     const struct ovs_key_sctp *key,
 570                     const struct ovs_key_sctp *mask)
 571 {
 572         unsigned int sctphoff = skb_transport_offset(skb);
 573         struct sctphdr *sh;
 574         __le32 old_correct_csum, new_csum, old_csum;
 575         int err;
 576
 577         err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
 578         if (unlikely(err))
 579                 return err;
 580
 581         sh = sctp_hdr(skb);
 582         old_csum = sh->checksum;
 583         old_correct_csum = sctp_compute_cksum(skb, sctphoff);
 584
 585         sh->source = MASKED(sh->source, key->sctp_src, mask->sctp_src);
 586         sh->dest = MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
 587
 588         new_csum = sctp_compute_cksum(skb, sctphoff);
 589
 590         /* Carry any checksum errors through. */
 591         sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
 592
 593         skb_clear_hash(skb);
 594         flow_key->tp.src = sh->source;
 595         flow_key->tp.dst = sh->dest;
 596
 597         return 0;
 598 }
 599
 600 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port)
 601 {
 602         struct vport *vport = ovs_vport_rcu(dp, out_port);
 603
 604         if (likely(vport))
 605                 ovs_vport_send(vport, skb);
 606         else
 607                 kfree_skb(skb);
 608 }
 609
 610 static int output_userspace(struct datapath *dp, struct sk_buff *skb,
 611                             struct sw_flow_key *key, const struct nlattr *attr,
 612                             const struct nlattr *actions, int actions_len)
 613 {
 614         struct ovs_tunnel_info info;
 615         struct dp_upcall_info upcall;
 616         const struct nlattr *a;
 617         int rem;
 618
 619         memset(&upcall, 0, sizeof(upcall));
 620         upcall.cmd = OVS_PACKET_CMD_ACTION;
 621
 622         for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
 623                  a = nla_next(a, &rem)) {
 624                 switch (nla_type(a)) {
 625                 case OVS_USERSPACE_ATTR_USERDATA:
 626                         upcall.userdata = a;
 627                         break;
 628
 629                 case OVS_USERSPACE_ATTR_PID:
 630                         upcall.portid = nla_get_u32(a);
 631                         break;
 632
 633                 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
 634                         /* Get out tunnel info. */
 635                         struct vport *vport;
 636
 637                         vport = ovs_vport_rcu(dp, nla_get_u32(a));
 638                         if (vport) {
 639                                 int err;
 640
 641                                 err = ovs_vport_get_egress_tun_info(vport, skb,
 642                                                                     &info);
 643                                 if (!err)
 644                                         upcall.egress_tun_info = &info;
 645                         }
 646                         break;
 647                 }
 648
 649                 case OVS_USERSPACE_ATTR_ACTIONS: {
 650                         /* Include actions. */
 651                         upcall.actions = actions;
 652                         upcall.actions_len = actions_len;
 653                         break;
 654                 }
 655
 656                 } /* End of switch. */
 657         }
 658
 659         return ovs_dp_upcall(dp, skb, key, &upcall);
 660 }
 661
 662 static int sample(struct datapath *dp, struct sk_buff *skb,
 663                   struct sw_flow_key *key, const struct nlattr *attr,
 664                   const struct nlattr *actions, int actions_len)
 665 {
 666         const struct nlattr *acts_list = NULL;
 667         const struct nlattr *a;
 668         int rem;
 669
 670         for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
 671                  a = nla_next(a, &rem)) {
 672                 switch (nla_type(a)) {
 673                 case OVS_SAMPLE_ATTR_PROBABILITY:
 674                         if (prandom_u32() >= nla_get_u32(a))
 675                                 return 0;
 676                         break;
 677
 678                 case OVS_SAMPLE_ATTR_ACTIONS:
 679                         acts_list = a;
 680                         break;
 681                 }
 682         }
 683
 684         rem = nla_len(acts_list);
 685         a = nla_data(acts_list);
 686
 687         /* Actions list is empty, do nothing */
 688         if (unlikely(!rem))
 689                 return 0;
 690
 691         /* The only known usage of sample action is having a single user-space
 692          * action. Treat this usage as a special case.
 693          * The output_userspace() should clone the skb to be sent to the
 694          * user space. This skb will be consumed by its caller.
 695          */
 696         if (likely(nla_type(a) == OVS_ACTION_ATTR_USERSPACE &&
 697                    nla_is_last(a, rem)))
 698                 return output_userspace(dp, skb, key, a, actions, actions_len);
 699
 700         skb = skb_clone(skb, GFP_ATOMIC);
 701         if (!skb)
 702                 /* Skip the sample action when out of memory. */
 703                 return 0;
 704
 705         if (!add_deferred_actions(skb, key, a)) {
 706                 if (net_ratelimit())
 707                         pr_warn("%s: deferred actions limit reached, dropping sample action\n",
 708                                 ovs_dp_name(dp));
 709
 710                 kfree_skb(skb);
 711         }
 712         return 0;
 713 }
 714
 715 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
 716                          const struct nlattr *attr)
 717 {
 718         struct ovs_action_hash *hash_act = nla_data(attr);
 719         u32 hash = 0;
 720
 721         /* OVS_HASH_ALG_L4 is the only possible hash algorithm.  */
 722         hash = skb_get_hash(skb);
 723         hash = jhash_1word(hash, hash_act->hash_basis);
 724         if (!hash)
 725                 hash = 0x1;
 726
 727         key->ovs_flow_hash = hash;
 728 }
 729
 730 static int execute_set_action(struct sk_buff *skb,
 731                               struct sw_flow_key *flow_key,
 732                               const struct nlattr *a)
 733 {
 734         /* Only tunnel set execution is supported without a mask. */
 735         if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
 736                 OVS_CB(skb)->egress_tun_info = nla_data(a);
 737                 return 0;
 738         }
 739
 740         return -EINVAL;
 741 }
 742
 743 /* Mask is at the midpoint of the data. */
 744 #define get_mask(a, type) ((const type)nla_data(a) + 1)
 745
 746 static int execute_masked_set_action(struct sk_buff *skb,
 747                                      struct sw_flow_key *flow_key,
 748                                      const struct nlattr *a)
 749 {
 750         int err = 0;
 751
 752         switch (nla_type(a)) {
 753         case OVS_KEY_ATTR_PRIORITY:
 754                 SET_MASKED(skb->priority, nla_get_u32(a), *get_mask(a, u32 *));
 755                 flow_key->phy.priority = skb->priority;
 756                 break;
 757
 758         case OVS_KEY_ATTR_SKB_MARK:
 759                 SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
 760                 flow_key->phy.skb_mark = skb->mark;
 761                 break;
 762
 763         case OVS_KEY_ATTR_TUNNEL_INFO:
 764                 /* Masked data not supported for tunnel. */
 765                 err = -EINVAL;
 766                 break;
 767
 768         case OVS_KEY_ATTR_ETHERNET:
 769                 err = set_eth_addr(skb, flow_key, nla_data(a),
 770                                    get_mask(a, struct ovs_key_ethernet *));
 771                 break;
 772
 773         case OVS_KEY_ATTR_IPV4:
 774                 err = set_ipv4(skb, flow_key, nla_data(a),
 775                                get_mask(a, struct ovs_key_ipv4 *));
 776                 break;
 777
 778         case OVS_KEY_ATTR_IPV6:
 779                 err = set_ipv6(skb, flow_key, nla_data(a),
 780                                get_mask(a, struct ovs_key_ipv6 *));
 781                 break;
 782
 783         case OVS_KEY_ATTR_TCP:
 784                 err = set_tcp(skb, flow_key, nla_data(a),
 785                               get_mask(a, struct ovs_key_tcp *));
 786                 break;
 787
 788         case OVS_KEY_ATTR_UDP:
 789                 err = set_udp(skb, flow_key, nla_data(a),
 790                               get_mask(a, struct ovs_key_udp *));
 791                 break;
 792
 793         case OVS_KEY_ATTR_SCTP:
 794                 err = set_sctp(skb, flow_key, nla_data(a),
 795                                get_mask(a, struct ovs_key_sctp *));
 796                 break;
 797
 798         case OVS_KEY_ATTR_MPLS:
 799                 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
 800                                                                     __be32 *));
 801                 break;
 802         }
 803
 804         return err;
 805 }
 806
 807 static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
 808                           struct sw_flow_key *key,
 809                           const struct nlattr *a, int rem)
 810 {
 811         struct deferred_action *da;
 812
 813         if (!is_flow_key_valid(key)) {
 814                 int err;
 815
 816                 err = ovs_flow_key_update(skb, key);
 817                 if (err)
 818                         return err;
 819         }
 820         BUG_ON(!is_flow_key_valid(key));
 821
 822         if (!nla_is_last(a, rem)) {
 823                 /* Recirc action is the not the last action
 824                  * of the action list, need to clone the skb.
 825                  */
 826                 skb = skb_clone(skb, GFP_ATOMIC);
 827
 828                 /* Skip the recirc action when out of memory, but
 829                  * continue on with the rest of the action list.
 830                  */
 831                 if (!skb)
 832                         return 0;
 833         }
 834
 835         da = add_deferred_actions(skb, key, NULL);
 836         if (da) {
 837                 da->pkt_key.recirc_id = nla_get_u32(a);
 838         } else {
 839                 kfree_skb(skb);
 840
 841                 if (net_ratelimit())
 842                         pr_warn("%s: deferred action limit reached, drop recirc action\n",
 843                                 ovs_dp_name(dp));
 844         }
 845
 846         return 0;
 847 }
 848
 849 /* Execute a list of actions against 'skb'. */
 850 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
 851                               struct sw_flow_key *key,
 852                               const struct nlattr *attr, int len)
 853 {
 854         /* Every output action needs a separate clone of 'skb', but the common
 855          * case is just a single output action, so that doing a clone and
 856          * then freeing the original skbuff is wasteful.  So the following code
 857          * is slightly obscure just to avoid that.
 858          */
 859         int prev_port = -1;
 860         const struct nlattr *a;
 861         int rem;
 862
 863         for (a = attr, rem = len; rem > 0;
 864              a = nla_next(a, &rem)) {
 865                 int err = 0;
 866
 867                 if (unlikely(prev_port != -1)) {
 868                         struct sk_buff *out_skb = skb_clone(skb, GFP_ATOMIC);
 869
 870                         if (out_skb)
 871                                 do_output(dp, out_skb, prev_port);
 872
 873                         prev_port = -1;
 874                 }
 875
 876                 switch (nla_type(a)) {
 877                 case OVS_ACTION_ATTR_OUTPUT:
 878                         prev_port = nla_get_u32(a);
 879                         break;
 880
 881                 case OVS_ACTION_ATTR_USERSPACE:
 882                         output_userspace(dp, skb, key, a, attr, len);
 883                         break;
 884
 885                 case OVS_ACTION_ATTR_HASH:
 886                         execute_hash(skb, key, a);
 887                         break;
 888
 889                 case OVS_ACTION_ATTR_PUSH_MPLS:
 890                         err = push_mpls(skb, key, nla_data(a));
 891                         break;
 892
 893                 case OVS_ACTION_ATTR_POP_MPLS:
 894                         err = pop_mpls(skb, key, nla_get_be16(a));
 895                         break;
 896
 897                 case OVS_ACTION_ATTR_PUSH_VLAN:
 898                         err = push_vlan(skb, key, nla_data(a));
 899                         break;
 900
 901                 case OVS_ACTION_ATTR_POP_VLAN:
 902                         err = pop_vlan(skb, key);
 903                         break;
 904
 905                 case OVS_ACTION_ATTR_RECIRC:
 906                         err = execute_recirc(dp, skb, key, a, rem);
 907                         if (nla_is_last(a, rem)) {
 908                                 /* If this is the last action, the skb has
 909                                  * been consumed or freed.
 910                                  * Return immediately.
 911                                  */
 912                                 return err;
 913                         }
 914                         break;
 915
 916                 case OVS_ACTION_ATTR_SET:
 917                         err = execute_set_action(skb, key, nla_data(a));
 918                         break;
 919
 920                 case OVS_ACTION_ATTR_SET_MASKED:
 921                 case OVS_ACTION_ATTR_SET_TO_MASKED:
 922                         err = execute_masked_set_action(skb, key, nla_data(a));
 923                         break;
 924
 925                 case OVS_ACTION_ATTR_SAMPLE:
 926                         err = sample(dp, skb, key, a, attr, len);
 927                         break;
 928                 }
 929
 930                 if (unlikely(err)) {
 931                         kfree_skb(skb);
 932                         return err;
 933                 }
 934         }
 935
 936         if (prev_port != -1)
 937                 do_output(dp, skb, prev_port);
 938         else
 939                 consume_skb(skb);
 940
 941         return 0;
 942 }
 943
 944 static void process_deferred_actions(struct datapath *dp)
 945 {
 946         struct action_fifo *fifo = this_cpu_ptr(action_fifos);
 947
 948         /* Do not touch the FIFO in case there is no deferred actions. */
 949         if (action_fifo_is_empty(fifo))
 950                 return;
 951
 952         /* Finishing executing all deferred actions. */
 953         do {
 954                 struct deferred_action *da = action_fifo_get(fifo);
 955                 struct sk_buff *skb = da->skb;
 956                 struct sw_flow_key *key = &da->pkt_key;
 957                 const struct nlattr *actions = da->actions;
 958
 959                 if (actions)
 960                         do_execute_actions(dp, skb, key, actions,
 961                                            nla_len(actions));
 962                 else
 963                         ovs_dp_process_packet(skb, key);
 964         } while (!action_fifo_is_empty(fifo));
 965
 966         /* Reset FIFO for the next packet.  */
 967         action_fifo_init(fifo);
 968 }
 969
 970 /* Execute a list of actions against 'skb'. */
 971 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
 972                         const struct sw_flow_actions *acts,
 973                         struct sw_flow_key *key)
 974 {
 975         int level = this_cpu_read(exec_actions_level);
 976         int err;
 977
 978         this_cpu_inc(exec_actions_level);
 979         OVS_CB(skb)->egress_tun_info = NULL;
 980         err = do_execute_actions(dp, skb, key,
 981                                  acts->actions, acts->actions_len);
 982
 983         if (!level)
 984                 process_deferred_actions(dp);
 985
 986         this_cpu_dec(exec_actions_level);
 987         return err;
 988 }
 989
 990 int action_fifos_init(void)
 991 {
 992         action_fifos = alloc_percpu(struct action_fifo);
 993         if (!action_fifos)
 994                 return -ENOMEM;
 995
 996         return 0;
 997 }
 998
 999 void action_fifos_exit(void)
1000 {
1001         free_percpu(action_fifos);
1002 }