datapath/datapath.c

   1 /*
   2  * Distributed under the terms of the GNU GPL version 2.
   3  * Copyright (c) 2007, 2008 The Board of Trustees of The Leland
   4  * Stanford Junior University
   5  */
   6
   7 /* Functions for managing the dp interface/device. */
   8
   9 #include <linux/init.h>
  10 #include <linux/module.h>
  11 #include <linux/if_arp.h>
  12 #include <linux/if_bridge.h>
  13 #include <linux/if_vlan.h>
  14 #include <linux/in.h>
  15 #include <net/genetlink.h>
  16 #include <linux/ip.h>
  17 #include <linux/delay.h>
  18 #include <linux/etherdevice.h>
  19 #include <linux/kernel.h>
  20 #include <linux/kthread.h>
  21 #include <linux/mutex.h>
  22 #include <linux/rtnetlink.h>
  23 #include <linux/rcupdate.h>
  24 #include <linux/version.h>
  25 #include <linux/ethtool.h>
  26 #include <linux/random.h>
  27 #include <asm/system.h>
  28 #include <linux/netfilter_bridge.h>
  29 #include <linux/netfilter_ipv4.h>
  30 #include <linux/inetdevice.h>
  31 #include <linux/list.h>
  32 #include <linux/rculist.h>
  33 #include <linux/workqueue.h>
  34 #include <linux/dmi.h>
  35
  36 #include "openflow/nicira-ext.h"
  37 #include "openflow/openflow-netlink.h"
  38 #include "datapath.h"
  39 #include "nx_act_snat.h"
  40 #include "table.h"
  41 #include "chain.h"
  42 #include "dp_dev.h"
  43 #include "forward.h"
  44 #include "flow.h"
  45
  46 #include "compat.h"
  47
  48
  49 /* Strings to describe the manufacturer, hardware, and software.  This data
  50  * is queriable through the switch description stats message. */
  51 static char mfr_desc[DESC_STR_LEN] = "Nicira Networks, Inc.";
  52 static char hw_desc[DESC_STR_LEN] = "Reference Linux Kernel Module";
  53 static char sw_desc[DESC_STR_LEN] = VERSION BUILDNR;
  54 static char serial_num[SERIAL_NUM_LEN] = "None";
  55
  56 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
  57 module_param_string(mfr_desc, mfr_desc, sizeof mfr_desc, 0444);
  58 module_param_string(hw_desc, hw_desc, sizeof hw_desc, 0444);
  59 module_param_string(sw_desc, sw_desc, sizeof sw_desc, 0444);
  60 module_param_string(serial_num, serial_num, sizeof serial_num, 0444);
  61 #else
  62 MODULE_PARM(mfr_desc, "s");
  63 MODULE_PARM(hw_desc, "s");
  64 MODULE_PARM(sw_desc, "s");
  65 MODULE_PARM(serial_num, "s");
  66 #endif
  67
  68
  69 /* Number of milliseconds between runs of the maintenance thread. */
  70 #define MAINT_SLEEP_MSECS 1000
  71
  72 #define UINT32_MAX                        4294967295U
  73 #define UINT16_MAX                        65535
  74 #define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
  75
  76 static struct genl_family dp_genl_family;
  77 static struct genl_multicast_group mc_group;
  78
  79 /* It's hard to imagine wanting more than one datapath, but... */
  80 #define DP_MAX 32
  81
  82 /* Datapaths.  Protected on the read side by rcu_read_lock, on the write side
  83  * by dp_mutex.  dp_mutex is almost completely redundant with genl_mutex
  84  * maintained by the Generic Netlink code, but the timeout path needs mutual
  85  * exclusion too.
  86  *
  87  * It is safe to access the datapath and net_bridge_port structures with just
  88  * dp_mutex.
  89  */
  90 static struct datapath *dps[DP_MAX];
  91 DEFINE_MUTEX(dp_mutex);
  92 EXPORT_SYMBOL(dp_mutex);
  93
  94 static int dp_maint_func(void *data);
  95 static void init_port_status(struct net_bridge_port *p);
  96 static int dp_genl_openflow_done(struct netlink_callback *);
  97 static struct net_bridge_port *new_nbp(struct datapath *,
  98                                        struct net_device *, int port_no);
  99
 100 /* nla_shrink - reduce amount of space reserved by nla_reserve
 101  * @skb: socket buffer from which to recover room
 102  * @nla: netlink attribute to adjust
 103  * @len: new length of attribute payload
 104  *
 105  * Reduces amount of space reserved by a call to nla_reserve.
 106  *
 107  * No other attributes may be added between calling nla_reserve and this
 108  * function, since it will create a hole in the message.
 109  */
 110 void nla_shrink(struct sk_buff *skb, struct nlattr *nla, int len)
 111 {
 112         int delta = nla_total_size(len) - nla_total_size(nla_len(nla));
 113         BUG_ON(delta > 0);
 114         skb->tail += delta;
 115         skb->len  += delta;
 116         nla->nla_len = nla_attr_size(len);
 117 }
 118
 119 /* Puts a set of openflow headers for a message of the given 'type' into 'skb'.
 120  * If 'sender' is nonnull, then it is used as the message's destination.  'dp'
 121  * must specify the datapath to use.
 122  *
 123  * '*max_openflow_len' receives the maximum number of bytes that are available
 124  * for the embedded OpenFlow message.  The caller must call
 125  * resize_openflow_skb() to set the actual size of the message to this number
 126  * of bytes or less.
 127  *
 128  * Returns the openflow header if successful, otherwise (if 'skb' is too small)
 129  * an error code. */
 130 static void *
 131 put_openflow_headers(struct datapath *dp, struct sk_buff *skb, uint8_t type,
 132                      const struct sender *sender, int *max_openflow_len)
 133 {
 134         struct ofp_header *oh;
 135         struct nlattr *attr;
 136         int openflow_len;
 137
 138         /* Assemble the Generic Netlink wrapper. */
 139         if (!genlmsg_put(skb,
 140                          sender ? sender->pid : 0,
 141                          sender ? sender->seq : 0,
 142                          &dp_genl_family, 0, DP_GENL_C_OPENFLOW))
 143                 return ERR_PTR(-ENOBUFS);
 144         if (nla_put_u32(skb, DP_GENL_A_DP_IDX, dp->dp_idx) < 0)
 145                 return ERR_PTR(-ENOBUFS);
 146         openflow_len = (skb_tailroom(skb) - NLA_HDRLEN) & ~(NLA_ALIGNTO - 1);
 147         if (openflow_len < sizeof *oh)
 148                 return ERR_PTR(-ENOBUFS);
 149         *max_openflow_len = openflow_len;
 150         attr = nla_reserve(skb, DP_GENL_A_OPENFLOW, openflow_len);
 151         BUG_ON(!attr);
 152
 153         /* Fill in the header.  The caller is responsible for the length. */
 154         oh = nla_data(attr);
 155         oh->version = OFP_VERSION;
 156         oh->type = type;
 157         oh->xid = sender ? sender->xid : 0;
 158
 159         return oh;
 160 }
 161
 162 /* Resizes OpenFlow header 'oh', which must be at the tail end of 'skb', to new
 163  * length 'new_length' (in bytes), adjusting pointers and size values as
 164  * necessary. */
 165 static void
 166 resize_openflow_skb(struct sk_buff *skb,
 167                     struct ofp_header *oh, size_t new_length)
 168 {
 169         struct nlattr *attr = ((void *) oh) - NLA_HDRLEN;
 170         nla_shrink(skb, attr, new_length);
 171         oh->length = htons(new_length);
 172         nlmsg_end(skb, (struct nlmsghdr *) skb->data);
 173 }
 174
 175 /* Allocates a new skb to contain an OpenFlow message 'openflow_len' bytes in
 176  * length.  Returns a null pointer if memory is unavailable, otherwise returns
 177  * the OpenFlow header and stores a pointer to the skb in '*pskb'.
 178  *
 179  * 'type' is the OpenFlow message type.  If 'sender' is nonnull, then it is
 180  * used as the message's destination.  'dp' must specify the datapath to
 181  * use.  */
 182 static void *
 183 alloc_openflow_skb(struct datapath *dp, size_t openflow_len, uint8_t type,
 184                    const struct sender *sender, struct sk_buff **pskb)
 185 {
 186         struct ofp_header *oh;
 187         size_t genl_len;
 188         struct sk_buff *skb;
 189         int max_openflow_len;
 190
 191         if ((openflow_len + sizeof(struct ofp_header)) > UINT16_MAX) {
 192                 if (net_ratelimit())
 193                         printk("alloc_openflow_skb: openflow message too large: %zu\n",
 194                                         openflow_len);
 195                 return NULL;
 196         }
 197
 198         genl_len = nlmsg_total_size(GENL_HDRLEN + dp_genl_family.hdrsize);
 199         genl_len += nla_total_size(sizeof(uint32_t)); /* DP_GENL_A_DP_IDX */
 200         genl_len += nla_total_size(openflow_len);    /* DP_GENL_A_OPENFLOW */
 201         skb = *pskb = genlmsg_new(genl_len, GFP_ATOMIC);
 202         if (!skb) {
 203                 if (net_ratelimit())
 204                         printk("alloc_openflow_skb: genlmsg_new failed\n");
 205                 return NULL;
 206         }
 207
 208         oh = put_openflow_headers(dp, skb, type, sender, &max_openflow_len);
 209         BUG_ON(!oh || IS_ERR(oh));
 210         resize_openflow_skb(skb, oh, openflow_len);
 211
 212         return oh;
 213 }
 214
 215 /* Sends 'skb' to 'sender' if it is nonnull, otherwise multicasts 'skb' to all
 216  * listeners. */
 217 static int
 218 send_openflow_skb(struct sk_buff *skb, const struct sender *sender)
 219 {
 220         return (sender
 221                 ? genlmsg_unicast(skb, sender->pid)
 222                 : genlmsg_multicast(skb, 0, mc_group.id, GFP_ATOMIC));
 223 }
 224
 225 /* Retrieves the datapath id, which is the MAC address of the "of" device. */
 226 static
 227 uint64_t get_datapath_id(struct net_device *dev)
 228 {
 229         uint64_t id = 0;
 230         int i;
 231
 232         for (i=0; i<ETH_ALEN; i++)
 233                 id |= (uint64_t)dev->dev_addr[i] << (8*(ETH_ALEN-1 - i));
 234
 235         return id;
 236 }
 237
 238 /* Creates a new datapath numbered 'dp_idx'.  Returns 0 for success or a
 239  * negative error code. */
 240 static int new_dp(int dp_idx)
 241 {
 242         struct datapath *dp;
 243         int err;
 244
 245         if (dp_idx < 0 || dp_idx >= DP_MAX)
 246                 return -EINVAL;
 247
 248         if (!try_module_get(THIS_MODULE))
 249                 return -ENODEV;
 250
 251         /* Exit early if a datapath with that number already exists. */
 252         if (dps[dp_idx]) {
 253                 err = -EEXIST;
 254                 goto err_unlock;
 255         }
 256
 257         err = -ENOMEM;
 258         dp = kzalloc(sizeof *dp, GFP_KERNEL);
 259         if (dp == NULL)
 260                 goto err_unlock;
 261
 262         /* Setup our "of" device */
 263         err = dp_dev_setup(dp);
 264         if (err)
 265                 goto err_free_dp;
 266
 267         dp->dp_idx = dp_idx;
 268         dp->id = get_datapath_id(dp->netdev);
 269         dp->chain = chain_create(dp);
 270         if (dp->chain == NULL)
 271                 goto err_destroy_dp_dev;
 272         INIT_LIST_HEAD(&dp->port_list);
 273
 274         dp->local_port = new_nbp(dp, dp->netdev, OFPP_LOCAL);
 275         if (IS_ERR(dp->local_port)) {
 276                 err = PTR_ERR(dp->local_port);
 277                 goto err_destroy_local_port;
 278         }
 279
 280         dp->flags = 0;
 281         dp->miss_send_len = OFP_DEFAULT_MISS_SEND_LEN;
 282
 283         dp->dp_task = kthread_run(dp_maint_func, dp, "dp%d", dp_idx);
 284         if (IS_ERR(dp->dp_task))
 285                 goto err_destroy_chain;
 286
 287         dps[dp_idx] = dp;
 288
 289         return 0;
 290
 291 err_destroy_local_port:
 292         dp_del_switch_port(dp->local_port);
 293 err_destroy_chain:
 294         chain_destroy(dp->chain);
 295 err_destroy_dp_dev:
 296         dp_dev_destroy(dp);
 297 err_free_dp:
 298         kfree(dp);
 299 err_unlock:
 300         module_put(THIS_MODULE);
 301                 return err;
 302 }
 303
 304 /* Find and return a free port number under 'dp'. */
 305 static int find_portno(struct datapath *dp)
 306 {
 307         int i;
 308         for (i = 0; i < DP_MAX_PORTS; i++)
 309                 if (dp->ports[i] == NULL)
 310                         return i;
 311         return -EXFULL;
 312 }
 313
 314 static struct net_bridge_port *new_nbp(struct datapath *dp,
 315                                        struct net_device *dev, int port_no)
 316 {
 317         struct net_bridge_port *p;
 318
 319         if (dev->br_port != NULL)
 320                 return ERR_PTR(-EBUSY);
 321
 322         p = kzalloc(sizeof(*p), GFP_KERNEL);
 323         if (p == NULL)
 324                 return ERR_PTR(-ENOMEM);
 325
 326         rtnl_lock();
 327         dev_set_promiscuity(dev, 1);
 328         rtnl_unlock();
 329         dev_hold(dev);
 330         p->dp = dp;
 331         p->dev = dev;
 332         p->port_no = port_no;
 333         spin_lock_init(&p->lock);
 334         INIT_WORK(&p->port_task, NULL);
 335         if (port_no != OFPP_LOCAL)
 336                 rcu_assign_pointer(dev->br_port, p);
 337         if (port_no < DP_MAX_PORTS)
 338                 rcu_assign_pointer(dp->ports[port_no], p);
 339         list_add_rcu(&p->node, &dp->port_list);
 340
 341         return p;
 342 }
 343
 344 int add_switch_port(struct datapath *dp, struct net_device *dev)
 345 {
 346         struct net_bridge_port *p;
 347         int port_no;
 348
 349         if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER
 350             || is_dp_dev(dev))
 351                 return -EINVAL;
 352
 353         port_no = find_portno(dp);
 354         if (port_no < 0)
 355                 return port_no;
 356
 357         p = new_nbp(dp, dev, port_no);
 358         if (IS_ERR(p))
 359                 return PTR_ERR(p);
 360
 361         init_port_status(p);
 362
 363         /* Notify the ctlpath that this port has been added */
 364         dp_send_port_status(p, OFPPR_ADD);
 365
 366         return 0;
 367 }
 368
 369 /* Delete 'p' from switch. */
 370 int dp_del_switch_port(struct net_bridge_port *p)
 371 {
 372 #ifdef SUPPORT_SNAT
 373         unsigned long flags;
 374 #endif
 375
 376         /* First drop references to device. */
 377         cancel_work_sync(&p->port_task);
 378         rtnl_lock();
 379         dev_set_promiscuity(p->dev, -1);
 380         rtnl_unlock();
 381         list_del_rcu(&p->node);
 382         if (p->port_no != OFPP_LOCAL)
 383                 rcu_assign_pointer(p->dp->ports[p->port_no], NULL);
 384         rcu_assign_pointer(p->dev->br_port, NULL);
 385
 386         /* Then wait until no one is still using it, and destroy it. */
 387         synchronize_rcu();
 388
 389 #ifdef SUPPORT_SNAT
 390         /* Free any SNAT configuration on the port. */
 391         spin_lock_irqsave(&p->lock, flags);
 392         snat_free_conf(p);
 393         spin_unlock_irqrestore(&p->lock, flags);
 394 #endif
 395
 396         /* Notify the ctlpath that this port no longer exists */
 397         dp_send_port_status(p, OFPPR_DELETE);
 398
 399         dev_put(p->dev);
 400         kfree(p);
 401
 402         return 0;
 403 }
 404
 405 static void del_dp(struct datapath *dp)
 406 {
 407         struct net_bridge_port *p, *n;
 408
 409         kthread_stop(dp->dp_task);
 410
 411         /* Drop references to DP. */
 412         list_for_each_entry_safe (p, n, &dp->port_list, node)
 413                 dp_del_switch_port(p);
 414         rcu_assign_pointer(dps[dp->dp_idx], NULL);
 415
 416         /* Kill off local_port dev references from buffered packets that have
 417          * associated dst entries. */
 418         synchronize_rcu();
 419         fwd_discard_all();
 420
 421         /* Destroy dp->netdev.  (Must follow deleting switch ports since
 422          * dp->local_port has a reference to it.) */
 423         dp_dev_destroy(dp);
 424
 425         /* Wait until no longer in use, then destroy it. */
 426         synchronize_rcu();
 427         chain_destroy(dp->chain);
 428         kfree(dp);
 429         module_put(THIS_MODULE);
 430 }
 431
 432 static int dp_maint_func(void *data)
 433 {
 434         struct datapath *dp = (struct datapath *) data;
 435
 436         while (!kthread_should_stop()) {
 437 #ifdef SUPPORT_SNAT
 438                 struct net_bridge_port *p;
 439
 440                 /* Expire old SNAT entries */
 441                 rcu_read_lock();
 442                 list_for_each_entry_rcu (p, &dp->port_list, node)
 443                         snat_maint(p);
 444                 rcu_read_unlock();
 445 #endif
 446
 447                 /* Timeout old entries */
 448                 chain_timeout(dp->chain);
 449                 msleep_interruptible(MAINT_SLEEP_MSECS);
 450         }
 451
 452         return 0;
 453 }
 454
 455 static void
 456 do_port_input(struct net_bridge_port *p, struct sk_buff *skb)
 457 {
 458         /* Make our own copy of the packet.  Otherwise we will mangle the
 459          * packet for anyone who came before us (e.g. tcpdump via AF_PACKET).
 460          * (No one comes after us, since we tell handle_bridge() that we took
 461          * the packet.) */
 462         skb = skb_share_check(skb, GFP_ATOMIC);
 463         if (!skb)
 464                 return;
 465
 466 #ifdef SUPPORT_SNAT
 467         /* Check if this packet needs early SNAT processing. */
 468         if (snat_pre_route(skb)) {
 469                 kfree_skb(skb);
 470                 return;
 471         }
 472 #endif
 473
 474         /* Push the Ethernet header back on. */
 475         skb_push(skb, ETH_HLEN);
 476         skb_reset_mac_header(skb);
 477         fwd_port_input(p->dp->chain, skb, p);
 478 }
 479
 480 /*
 481  * Used as br_handle_frame_hook.  (Cannot run bridge at the same time, even on
 482  * different set of devices!)
 483  */
 484 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
 485 /* Called with rcu_read_lock. */
 486 static struct sk_buff *dp_frame_hook(struct net_bridge_port *p,
 487                                          struct sk_buff *skb)
 488 {
 489         do_port_input(p, skb);
 490         return NULL;
 491 }
 492 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
 493 static int dp_frame_hook(struct net_bridge_port *p, struct sk_buff **pskb)
 494 {
 495         do_port_input(p, *pskb);
 496         return 1;
 497 }
 498 #else
 499 /* NB: This has only been tested on 2.4.35 */
 500 static void dp_frame_hook(struct sk_buff *skb)
 501 {
 502         struct net_bridge_port *p = skb->dev->br_port;
 503         if (p) {
 504                 rcu_read_lock();
 505                 do_port_input(p, skb);
 506                 rcu_read_unlock();
 507         } else
 508                 kfree_skb(skb);
 509 }
 510 #endif
 511
 512 /* Forwarding output path.
 513  * Based on net/bridge/br_forward.c. */
 514
 515 static inline unsigned packet_length(const struct sk_buff *skb)
 516 {
 517         int length = skb->len - ETH_HLEN;
 518         if (skb->protocol == htons(ETH_P_8021Q))
 519                 length -= VLAN_HLEN;
 520         return length;
 521 }
 522
 523 /* Send packets out all the ports except the originating one.  If the
 524  * "flood" argument is set, only send along the minimum spanning tree.
 525  */
 526 static int
 527 output_all(struct datapath *dp, struct sk_buff *skb, int flood)
 528 {
 529         u32 disable = flood ? OFPPC_NO_FLOOD : 0;
 530         struct net_bridge_port *p;
 531         int prev_port = -1;
 532
 533         list_for_each_entry_rcu (p, &dp->port_list, node) {
 534                 if (skb->dev == p->dev || p->config & disable)
 535                         continue;
 536                 if (prev_port != -1) {
 537                         struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
 538                         if (!clone) {
 539                                 kfree_skb(skb);
 540                                 return -ENOMEM;
 541                         }
 542                         dp_output_port(dp, clone, prev_port, 0);
 543                 }
 544                 prev_port = p->port_no;
 545         }
 546         if (prev_port != -1)
 547                 dp_output_port(dp, skb, prev_port, 0);
 548         else
 549                 kfree_skb(skb);
 550
 551         return 0;
 552 }
 553
 554 /* Marks 'skb' as having originated from 'in_port' in 'dp'.
 555    FIXME: how are devices reference counted? */
 556 void dp_set_origin(struct datapath *dp, uint16_t in_port,
 557                            struct sk_buff *skb)
 558 {
 559         struct net_bridge_port *p;
 560         p = (in_port < DP_MAX_PORTS ? dp->ports[in_port]
 561              : in_port == OFPP_LOCAL ? dp->local_port
 562              : NULL);
 563         if (p)
 564                 skb->dev = p->dev;
 565          else
 566                 skb->dev = NULL;
 567 }
 568
 569 int
 570 dp_xmit_skb(struct sk_buff *skb)
 571 {
 572         int len = skb->len;
 573         if (packet_length(skb) > skb->dev->mtu) {
 574                 printk("dropped over-mtu packet: %d > %d\n",
 575                            packet_length(skb), skb->dev->mtu);
 576                 kfree_skb(skb);
 577                 return -E2BIG;
 578         }
 579
 580         dev_queue_xmit(skb);
 581
 582         return len;
 583 }
 584
 585 /* Takes ownership of 'skb' and transmits it to 'out_port' on 'dp'.
 586  */
 587 int dp_output_port(struct datapath *dp, struct sk_buff *skb, int out_port,
 588                    int ignore_no_fwd)
 589 {
 590         BUG_ON(!skb);
 591         switch (out_port){
 592         case OFPP_IN_PORT:
 593                 /* Send it out the port it came in on, which is already set in
 594                  * the skb. */
 595                 if (!skb->dev) {
 596                         if (net_ratelimit())
 597                                 printk("skb device not set forwarding to in_port\n");
 598                         kfree_skb(skb);
 599                         return -ESRCH;
 600                 }
 601                 return dp_xmit_skb(skb);
 602
 603         case OFPP_TABLE: {
 604                 int retval = run_flow_through_tables(dp->chain, skb,
 605                                                      skb->dev->br_port);
 606                 if (retval)
 607                         kfree_skb(skb);
 608                 return retval;
 609         }
 610
 611         case OFPP_FLOOD:
 612                 return output_all(dp, skb, 1);
 613
 614         case OFPP_ALL:
 615                 return output_all(dp, skb, 0);
 616
 617         case OFPP_CONTROLLER:
 618                 return dp_output_control(dp, skb, fwd_save_skb(skb), 0,
 619                                                   OFPR_ACTION);
 620
 621         case OFPP_LOCAL: {
 622                 struct net_device *dev = dp->netdev;
 623 #ifdef SUPPORT_SNAT
 624                 snat_local_in(skb);
 625 #endif
 626                 return dev ? dp_dev_recv(dev, skb) : -ESRCH;
 627         }
 628
 629         case 0 ... DP_MAX_PORTS - 1: {
 630                 struct net_bridge_port *p = dp->ports[out_port];
 631                 if (p == NULL)
 632                         goto bad_port;
 633                 if (p->dev == skb->dev) {
 634                         /* To send to the input port, must use OFPP_IN_PORT */
 635                         kfree_skb(skb);
 636                         if (net_ratelimit())
 637                                 printk("can't directly forward to input port\n");
 638                         return -EINVAL;
 639                 }
 640                 if (p->config & OFPPC_NO_FWD && !ignore_no_fwd) {
 641                         kfree_skb(skb);
 642                         return 0;
 643                 }
 644                 skb->dev = p->dev;
 645                 return dp_xmit_skb(skb);
 646         }
 647
 648         default:
 649                 goto bad_port;
 650         }
 651
 652 bad_port:
 653         kfree_skb(skb);
 654         if (net_ratelimit())
 655                 printk("can't forward to bad port %d\n", out_port);
 656         return -ENOENT;
 657 }
 658
 659 /* Takes ownership of 'skb' and transmits it to 'dp''s control path.  If
 660  * 'buffer_id' != -1, then only the first 64 bytes of 'skb' are sent;
 661  * otherwise, all of 'skb' is sent.  'reason' indicates why 'skb' is being
 662  * sent. 'max_len' sets the maximum number of bytes that the caller
 663  * wants to be sent; a value of 0 indicates the entire packet should be
 664  * sent. */
 665 int
 666 dp_output_control(struct datapath *dp, struct sk_buff *skb,
 667                            uint32_t buffer_id, size_t max_len, int reason)
 668 {
 669         /* FIXME?  Can we avoid creating a new skbuff in the case where we
 670          * forward the whole packet? */
 671         struct sk_buff *f_skb;
 672         struct ofp_packet_in *opi;
 673         size_t fwd_len, opi_len;
 674         int err;
 675
 676         fwd_len = skb->len;
 677         if ((buffer_id != (uint32_t) -1) && max_len)
 678                 fwd_len = min(fwd_len, max_len);
 679
 680         opi_len = offsetof(struct ofp_packet_in, data) + fwd_len;
 681         opi = alloc_openflow_skb(dp, opi_len, OFPT_PACKET_IN, NULL, &f_skb);
 682         if (!opi) {
 683                 err = -ENOMEM;
 684                 goto out;
 685         }
 686         opi->buffer_id      = htonl(buffer_id);
 687         opi->total_len      = htons(skb->len);
 688         opi->in_port        = htons(skb->dev && skb->dev->br_port
 689                                     ? skb->dev->br_port->port_no
 690                                     : OFPP_LOCAL);
 691         opi->reason         = reason;
 692         opi->pad            = 0;
 693         skb_copy_bits(skb, 0, opi->data, fwd_len);
 694         err = send_openflow_skb(f_skb, NULL);
 695
 696 out:
 697         kfree_skb(skb);
 698         return err;
 699 }
 700
 701 static void fill_port_desc(struct net_bridge_port *p, struct ofp_phy_port *desc)
 702 {
 703         unsigned long flags;
 704         desc->port_no = htons(p->port_no);
 705         strncpy(desc->name, p->dev->name, OFP_MAX_PORT_NAME_LEN);
 706         desc->name[OFP_MAX_PORT_NAME_LEN-1] = '\0';
 707         memcpy(desc->hw_addr, p->dev->dev_addr, ETH_ALEN);
 708         desc->curr = 0;
 709         desc->supported = 0;
 710         desc->advertised = 0;
 711         desc->peer = 0;
 712
 713         spin_lock_irqsave(&p->lock, flags);
 714         desc->config = htonl(p->config);
 715         desc->state = htonl(p->state);
 716         spin_unlock_irqrestore(&p->lock, flags);
 717
 718 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,24)
 719         if (p->dev->ethtool_ops && p->dev->ethtool_ops->get_settings) {
 720                 struct ethtool_cmd ecmd = { .cmd = ETHTOOL_GSET };
 721
 722                 if (!p->dev->ethtool_ops->get_settings(p->dev, &ecmd)) {
 723                         /* Set the supported features */
 724                         if (ecmd.supported & SUPPORTED_10baseT_Half)
 725                                 desc->supported |= OFPPF_10MB_HD;
 726                         if (ecmd.supported & SUPPORTED_10baseT_Full)
 727                                 desc->supported |= OFPPF_10MB_FD;
 728                         if (ecmd.supported & SUPPORTED_100baseT_Half)
 729                                 desc->supported |= OFPPF_100MB_HD;
 730                         if (ecmd.supported & SUPPORTED_100baseT_Full)
 731                                 desc->supported |= OFPPF_100MB_FD;
 732                         if (ecmd.supported & SUPPORTED_1000baseT_Half)
 733                                 desc->supported |= OFPPF_1GB_HD;
 734                         if (ecmd.supported & SUPPORTED_1000baseT_Full)
 735                                 desc->supported |= OFPPF_1GB_FD;
 736                         if (ecmd.supported & SUPPORTED_10000baseT_Full)
 737                                 desc->supported |= OFPPF_10GB_FD;
 738                         if (ecmd.supported & SUPPORTED_TP)
 739                                 desc->supported |= OFPPF_COPPER;
 740                         if (ecmd.supported & SUPPORTED_FIBRE)
 741                                 desc->supported |= OFPPF_FIBER;
 742                         if (ecmd.supported & SUPPORTED_Autoneg)
 743                                 desc->supported |= OFPPF_AUTONEG;
 744 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14)
 745                         if (ecmd.supported & SUPPORTED_Pause)
 746                                 desc->supported |= OFPPF_PAUSE;
 747                         if (ecmd.supported & SUPPORTED_Asym_Pause)
 748                                 desc->supported |= OFPPF_PAUSE_ASYM;
 749 #endif /* kernel >= 2.6.14 */
 750
 751                         /* Set the advertised features */
 752                         if (ecmd.advertising & ADVERTISED_10baseT_Half)
 753                                 desc->advertised |= OFPPF_10MB_HD;
 754                         if (ecmd.advertising & ADVERTISED_10baseT_Full)
 755                                 desc->advertised |= OFPPF_10MB_FD;
 756                         if (ecmd.advertising & ADVERTISED_100baseT_Half)
 757                                 desc->advertised |= OFPPF_100MB_HD;
 758                         if (ecmd.advertising & ADVERTISED_100baseT_Full)
 759                                 desc->advertised |= OFPPF_100MB_FD;
 760                         if (ecmd.advertising & ADVERTISED_1000baseT_Half)
 761                                 desc->advertised |= OFPPF_1GB_HD;
 762                         if (ecmd.advertising & ADVERTISED_1000baseT_Full)
 763                                 desc->advertised |= OFPPF_1GB_FD;
 764                         if (ecmd.advertising & ADVERTISED_10000baseT_Full)
 765                                 desc->advertised |= OFPPF_10GB_FD;
 766                         if (ecmd.advertising & ADVERTISED_TP)
 767                                 desc->advertised |= OFPPF_COPPER;
 768                         if (ecmd.advertising & ADVERTISED_FIBRE)
 769                                 desc->advertised |= OFPPF_FIBER;
 770                         if (ecmd.advertising & ADVERTISED_Autoneg)
 771                                 desc->advertised |= OFPPF_AUTONEG;
 772 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14)
 773                         if (ecmd.advertising & ADVERTISED_Pause)
 774                                 desc->advertised |= OFPPF_PAUSE;
 775                         if (ecmd.advertising & ADVERTISED_Asym_Pause)
 776                                 desc->advertised |= OFPPF_PAUSE_ASYM;
 777 #endif /* kernel >= 2.6.14 */
 778
 779                         /* Set the current features */
 780                         if (ecmd.speed == SPEED_10)
 781                                 desc->curr = (ecmd.duplex) ? OFPPF_10MB_FD : OFPPF_10MB_HD;
 782                         else if (ecmd.speed == SPEED_100)
 783                                 desc->curr = (ecmd.duplex) ? OFPPF_100MB_FD : OFPPF_100MB_HD;
 784                         else if (ecmd.speed == SPEED_1000)
 785                                 desc->curr = (ecmd.duplex) ? OFPPF_1GB_FD : OFPPF_1GB_HD;
 786                         else if (ecmd.speed == SPEED_10000)
 787                                 desc->curr = OFPPF_10GB_FD;
 788
 789                         if (ecmd.port == PORT_TP)
 790                                 desc->curr |= OFPPF_COPPER;
 791                         else if (ecmd.port == PORT_FIBRE)
 792                                 desc->curr |= OFPPF_FIBER;
 793
 794                         if (ecmd.autoneg)
 795                                 desc->curr |= OFPPF_AUTONEG;
 796                 }
 797         }
 798 #endif
 799         desc->curr = htonl(desc->curr);
 800         desc->supported = htonl(desc->supported);
 801         desc->advertised = htonl(desc->advertised);
 802         desc->peer = htonl(desc->peer);
 803 }
 804
 805 static int
 806 fill_features_reply(struct datapath *dp, struct ofp_switch_features *ofr)
 807 {
 808         struct net_bridge_port *p;
 809         int port_count = 0;
 810
 811         ofr->datapath_id  = cpu_to_be64(dp->id);
 812
 813         ofr->n_buffers    = htonl(N_PKT_BUFFERS);
 814         ofr->n_tables     = dp->chain->n_tables;
 815         ofr->capabilities = htonl(OFP_SUPPORTED_CAPABILITIES);
 816         ofr->actions      = htonl(OFP_SUPPORTED_ACTIONS);
 817         memset(ofr->pad, 0, sizeof ofr->pad);
 818
 819         list_for_each_entry_rcu (p, &dp->port_list, node) {
 820                 fill_port_desc(p, &ofr->ports[port_count]);
 821                 port_count++;
 822         }
 823
 824         return port_count;
 825 }
 826
 827 int
 828 dp_send_features_reply(struct datapath *dp, const struct sender *sender)
 829 {
 830         struct sk_buff *skb;
 831         struct ofp_switch_features *ofr;
 832         size_t ofr_len, port_max_len;
 833         int port_count;
 834
 835         /* Overallocate. */
 836         port_max_len = sizeof(struct ofp_phy_port) * DP_MAX_PORTS;
 837         ofr = alloc_openflow_skb(dp, sizeof(*ofr) + port_max_len,
 838                                  OFPT_FEATURES_REPLY, sender, &skb);
 839         if (!ofr)
 840                 return -ENOMEM;
 841
 842         /* Fill. */
 843         port_count = fill_features_reply(dp, ofr);
 844
 845         /* Shrink to fit. */
 846         ofr_len = sizeof(*ofr) + (sizeof(struct ofp_phy_port) * port_count);
 847         resize_openflow_skb(skb, &ofr->header, ofr_len);
 848         return send_openflow_skb(skb, sender);
 849 }
 850
 851 int
 852 dp_send_config_reply(struct datapath *dp, const struct sender *sender)
 853 {
 854         struct sk_buff *skb;
 855         struct ofp_switch_config *osc;
 856
 857         osc = alloc_openflow_skb(dp, sizeof *osc, OFPT_GET_CONFIG_REPLY, sender,
 858                                  &skb);
 859         if (!osc)
 860                 return -ENOMEM;
 861
 862         osc->flags = htons(dp->flags);
 863         osc->miss_send_len = htons(dp->miss_send_len);
 864
 865         return send_openflow_skb(skb, sender);
 866 }
 867
 868 int
 869 dp_send_hello(struct datapath *dp, const struct sender *sender,
 870               const struct ofp_header *request)
 871 {
 872         if (request->version < OFP_VERSION) {
 873                 char err[64];
 874                 sprintf(err, "Only version 0x%02x supported", OFP_VERSION);
 875                 dp_send_error_msg(dp, sender, OFPET_HELLO_FAILED,
 876                                   OFPHFC_INCOMPATIBLE, err, strlen(err));
 877                 return -EINVAL;
 878         } else {
 879                 struct sk_buff *skb;
 880                 struct ofp_header *reply;
 881
 882                 reply = alloc_openflow_skb(dp, sizeof *reply,
 883                                            OFPT_HELLO, sender, &skb);
 884                 if (!reply)
 885                         return -ENOMEM;
 886
 887                 return send_openflow_skb(skb, sender);
 888         }
 889 }
 890
 891 /* Callback function for a workqueue to disable an interface */
 892 static void
 893 down_port_cb(struct work_struct *work)
 894 {
 895         struct net_bridge_port *p = container_of(work, struct net_bridge_port,
 896                         port_task);
 897
 898         rtnl_lock();
 899         if (dev_change_flags(p->dev, p->dev->flags & ~IFF_UP) < 0)
 900                 if (net_ratelimit())
 901                         printk("problem bringing up port %s\n", p->dev->name);
 902         rtnl_unlock();
 903         p->config |= OFPPC_PORT_DOWN;
 904 }
 905
 906 /* Callback function for a workqueue to enable an interface */
 907 static void
 908 up_port_cb(struct work_struct *work)
 909 {
 910         struct net_bridge_port *p = container_of(work, struct net_bridge_port,
 911                         port_task);
 912
 913         rtnl_lock();
 914         if (dev_change_flags(p->dev, p->dev->flags | IFF_UP) < 0)
 915                 if (net_ratelimit())
 916                         printk("problem bringing down port %s\n", p->dev->name);
 917         rtnl_unlock();
 918         p->config &= ~OFPPC_PORT_DOWN;
 919 }
 920
 921 int
 922 dp_update_port_flags(struct datapath *dp, const struct ofp_port_mod *opm)
 923 {
 924         unsigned long int flags;
 925         int port_no = ntohs(opm->port_no);
 926         struct net_bridge_port *p;
 927         p = (port_no < DP_MAX_PORTS ? dp->ports[port_no]
 928              : port_no == OFPP_LOCAL ? dp->local_port
 929              : NULL);
 930
 931         /* Make sure the port id hasn't changed since this was sent */
 932         if (!p || memcmp(opm->hw_addr, p->dev->dev_addr, ETH_ALEN))
 933                 return -1;
 934
 935         spin_lock_irqsave(&p->lock, flags);
 936         if (opm->mask) {
 937                 uint32_t config_mask = ntohl(opm->mask);
 938                 p->config &= ~config_mask;
 939                 p->config |= ntohl(opm->config) & config_mask;
 940         }
 941
 942         /* Modifying the status of an interface requires taking a lock
 943          * that cannot be done from here.  For this reason, we use a shared
 944          * workqueue, which will cause it to be executed from a safer
 945          * context. */
 946         if (opm->mask & htonl(OFPPC_PORT_DOWN)) {
 947                 if ((opm->config & htonl(OFPPC_PORT_DOWN))
 948                     && (p->config & OFPPC_PORT_DOWN) == 0) {
 949                         PREPARE_WORK(&p->port_task, down_port_cb);
 950                         schedule_work(&p->port_task);
 951                 } else if ((opm->config & htonl(OFPPC_PORT_DOWN)) == 0
 952                            && (p->config & OFPPC_PORT_DOWN)) {
 953                         PREPARE_WORK(&p->port_task, up_port_cb);
 954                         schedule_work(&p->port_task);
 955                 }
 956         }
 957         spin_unlock_irqrestore(&p->lock, flags);
 958
 959         return 0;
 960 }
 961
 962 /* Initialize the port status field of the bridge port. */
 963 static void
 964 init_port_status(struct net_bridge_port *p)
 965 {
 966         unsigned long int flags;
 967
 968         spin_lock_irqsave(&p->lock, flags);
 969
 970         if (p->dev->flags & IFF_UP)
 971                 p->config &= ~OFPPC_PORT_DOWN;
 972         else
 973                 p->config |= OFPPC_PORT_DOWN;
 974
 975         if (netif_carrier_ok(p->dev))
 976                 p->state &= ~OFPPS_LINK_DOWN;
 977         else
 978                 p->state |= OFPPS_LINK_DOWN;
 979
 980         spin_unlock_irqrestore(&p->lock, flags);
 981 }
 982
 983 int
 984 dp_send_port_status(struct net_bridge_port *p, uint8_t status)
 985 {
 986         struct sk_buff *skb;
 987         struct ofp_port_status *ops;
 988
 989         ops = alloc_openflow_skb(p->dp, sizeof *ops, OFPT_PORT_STATUS, NULL,
 990                                  &skb);
 991         if (!ops)
 992                 return -ENOMEM;
 993         ops->reason = status;
 994         memset(ops->pad, 0, sizeof ops->pad);
 995         fill_port_desc(p, &ops->desc);
 996
 997         return send_openflow_skb(skb, NULL);
 998 }
 999
1000 int
1001 dp_send_flow_expired(struct datapath *dp, struct sw_flow *flow,
1002                      enum ofp_flow_expired_reason reason)
1003 {
1004         struct sk_buff *skb;
1005         struct ofp_flow_expired *ofe;
1006
1007         if (!(dp->flags & OFPC_SEND_FLOW_EXP))
1008                 return 0;
1009
1010         ofe = alloc_openflow_skb(dp, sizeof *ofe, OFPT_FLOW_EXPIRED, 0, &skb);
1011         if (!ofe)
1012                 return -ENOMEM;
1013
1014         flow_fill_match(&ofe->match, &flow->key);
1015
1016         ofe->priority = htons(flow->priority);
1017         ofe->reason = reason;
1018         memset(ofe->pad, 0, sizeof ofe->pad);
1019
1020         ofe->duration     = htonl((jiffies - flow->init_time) / HZ);
1021         memset(ofe->pad2, 0, sizeof ofe->pad2);
1022         ofe->packet_count = cpu_to_be64(flow->packet_count);
1023         ofe->byte_count   = cpu_to_be64(flow->byte_count);
1024
1025         return send_openflow_skb(skb, NULL);
1026 }
1027 EXPORT_SYMBOL(dp_send_flow_expired);
1028
1029 int
1030 dp_send_error_msg(struct datapath *dp, const struct sender *sender,
1031                 uint16_t type, uint16_t code, const void *data, size_t len)
1032 {
1033         struct sk_buff *skb;
1034         struct ofp_error_msg *oem;
1035
1036
1037         oem = alloc_openflow_skb(dp, sizeof(*oem)+len, OFPT_ERROR,
1038                         sender, &skb);
1039         if (!oem)
1040                 return -ENOMEM;
1041
1042         oem->type = htons(type);
1043         oem->code = htons(code);
1044         memcpy(oem->data, data, len);
1045
1046         return send_openflow_skb(skb, sender);
1047 }
1048
1049 int
1050 dp_send_echo_reply(struct datapath *dp, const struct sender *sender,
1051                    const struct ofp_header *rq)
1052 {
1053         struct sk_buff *skb;
1054         struct ofp_header *reply;
1055
1056         reply = alloc_openflow_skb(dp, ntohs(rq->length), OFPT_ECHO_REPLY,
1057                                    sender, &skb);
1058         if (!reply)
1059                 return -ENOMEM;
1060
1061         memcpy(reply + 1, rq + 1, ntohs(rq->length) - sizeof *rq);
1062         return send_openflow_skb(skb, sender);
1063 }
1064
1065 /* Generic Netlink interface.
1066  *
1067  * See netlink(7) for an introduction to netlink.  See
1068  * http://linux-net.osdl.org/index.php/Netlink for more information and
1069  * pointers on how to work with netlink and Generic Netlink in the kernel and
1070  * in userspace. */
1071
1072 static struct genl_family dp_genl_family = {
1073         .id = GENL_ID_GENERATE,
1074         .hdrsize = 0,
1075         .name = DP_GENL_FAMILY_NAME,
1076         .version = 1,
1077         .maxattr = DP_GENL_A_MAX,
1078 };
1079
1080 /* Attribute policy: what each attribute may contain.  */
1081 static struct nla_policy dp_genl_policy[DP_GENL_A_MAX + 1] = {
1082         [DP_GENL_A_DP_IDX] = { .type = NLA_U32 },
1083         [DP_GENL_A_MC_GROUP] = { .type = NLA_U32 },
1084         [DP_GENL_A_PORTNAME] = { .type = NLA_STRING }
1085 };
1086
1087 static int dp_genl_add(struct sk_buff *skb, struct genl_info *info)
1088 {
1089         if (!info->attrs[DP_GENL_A_DP_IDX])
1090                 return -EINVAL;
1091
1092         return new_dp(nla_get_u32(info->attrs[DP_GENL_A_DP_IDX]));
1093 }
1094
1095 static struct genl_ops dp_genl_ops_add_dp = {
1096         .cmd = DP_GENL_C_ADD_DP,
1097         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1098         .policy = dp_genl_policy,
1099         .doit = dp_genl_add,
1100         .dumpit = NULL,
1101 };
1102
1103 struct datapath *dp_get(int dp_idx)
1104 {
1105         if (dp_idx < 0 || dp_idx > DP_MAX)
1106                 return NULL;
1107         return rcu_dereference(dps[dp_idx]);
1108 }
1109
1110 static int dp_genl_del(struct sk_buff *skb, struct genl_info *info)
1111 {
1112         struct datapath *dp;
1113         int err;
1114
1115         if (!info->attrs[DP_GENL_A_DP_IDX])
1116                 return -EINVAL;
1117
1118         dp = dp_get(nla_get_u32((info->attrs[DP_GENL_A_DP_IDX])));
1119         if (!dp)
1120                 err = -ENOENT;
1121         else {
1122                 del_dp(dp);
1123                 err = 0;
1124         }
1125         return err;
1126 }
1127
1128 static struct genl_ops dp_genl_ops_del_dp = {
1129         .cmd = DP_GENL_C_DEL_DP,
1130         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1131         .policy = dp_genl_policy,
1132         .doit = dp_genl_del,
1133         .dumpit = NULL,
1134 };
1135
1136 /* Queries a datapath for related information.  Currently the only relevant
1137  * information is the datapath's multicast group ID.  Really we want one
1138  * multicast group per datapath, but because of locking issues[*] we can't
1139  * easily get one.  Thus, every datapath will currently return the same
1140  * global multicast group ID, but in the future it would be nice to fix that.
1141  *
1142  * [*] dp_genl_add, to add a new datapath, is called under the genl_lock
1143  *       mutex, and genl_register_mc_group, called to acquire a new multicast
1144  *       group ID, also acquires genl_lock, thus deadlock.
1145  */
1146 static int dp_genl_query(struct sk_buff *skb, struct genl_info *info)
1147 {
1148         struct datapath *dp;
1149         struct sk_buff *ans_skb = NULL;
1150         int dp_idx;
1151         int err = -ENOMEM;
1152
1153         if (!info->attrs[DP_GENL_A_DP_IDX])
1154                 return -EINVAL;
1155
1156         rcu_read_lock();
1157         dp_idx = nla_get_u32((info->attrs[DP_GENL_A_DP_IDX]));
1158         dp = dp_get(dp_idx);
1159         if (!dp)
1160                 err = -ENOENT;
1161         else {
1162                 void *data;
1163                 ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1164                 if (!ans_skb) {
1165                         err = -ENOMEM;
1166                         goto err;
1167                 }
1168                 data = genlmsg_put_reply(ans_skb, info, &dp_genl_family,
1169                                          0, DP_GENL_C_QUERY_DP);
1170                 if (data == NULL) {
1171                         err = -ENOMEM;
1172                         goto err;
1173                 }
1174                 NLA_PUT_U32(ans_skb, DP_GENL_A_DP_IDX, dp_idx);
1175                 NLA_PUT_U32(ans_skb, DP_GENL_A_MC_GROUP, mc_group.id);
1176
1177                 genlmsg_end(ans_skb, data);
1178                 err = genlmsg_reply(ans_skb, info);
1179                 ans_skb = NULL;
1180         }
1181 err:
1182 nla_put_failure:
1183         kfree_skb(ans_skb);
1184         rcu_read_unlock();
1185         return err;
1186 }
1187
1188 static struct genl_ops dp_genl_ops_query_dp = {
1189         .cmd = DP_GENL_C_QUERY_DP,
1190         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1191         .policy = dp_genl_policy,
1192         .doit = dp_genl_query,
1193         .dumpit = NULL,
1194 };
1195
1196 static int dp_genl_add_del_port(struct sk_buff *skb, struct genl_info *info)
1197 {
1198         struct datapath *dp;
1199         struct net_device *port;
1200         int err;
1201
1202         if (!info->attrs[DP_GENL_A_DP_IDX] || !info->attrs[DP_GENL_A_PORTNAME])
1203                 return -EINVAL;
1204
1205         /* Get datapath. */
1206         dp = dp_get(nla_get_u32(info->attrs[DP_GENL_A_DP_IDX]));
1207         if (!dp) {
1208                 err = -ENOENT;
1209                 goto out;
1210         }
1211
1212         /* Get interface to add/remove. */
1213         port = dev_get_by_name(&init_net,
1214                         nla_data(info->attrs[DP_GENL_A_PORTNAME]));
1215         if (!port) {
1216                 err = -ENOENT;
1217                 goto out;
1218         }
1219
1220         /* Execute operation. */
1221         if (info->genlhdr->cmd == DP_GENL_C_ADD_PORT)
1222                 err = add_switch_port(dp, port);
1223         else {
1224                 if (port->br_port == NULL || port->br_port->dp != dp) {
1225                         err = -ENOENT;
1226                         goto out_put;
1227                 }
1228                 err = dp_del_switch_port(port->br_port);
1229         }
1230
1231 out_put:
1232         dev_put(port);
1233 out:
1234         return err;
1235 }
1236
1237 static struct genl_ops dp_genl_ops_add_port = {
1238         .cmd = DP_GENL_C_ADD_PORT,
1239         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1240         .policy = dp_genl_policy,
1241         .doit = dp_genl_add_del_port,
1242         .dumpit = NULL,
1243 };
1244
1245 static struct genl_ops dp_genl_ops_del_port = {
1246         .cmd = DP_GENL_C_DEL_PORT,
1247         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1248         .policy = dp_genl_policy,
1249         .doit = dp_genl_add_del_port,
1250         .dumpit = NULL,
1251 };
1252
1253 static int dp_genl_openflow(struct sk_buff *skb, struct genl_info *info)
1254 {
1255         struct nlattr *va = info->attrs[DP_GENL_A_OPENFLOW];
1256         struct datapath *dp;
1257         struct ofp_header *oh;
1258         struct sender sender;
1259         int err;
1260
1261         if (!info->attrs[DP_GENL_A_DP_IDX] || !va)
1262                 return -EINVAL;
1263
1264         dp = dp_get(nla_get_u32(info->attrs[DP_GENL_A_DP_IDX]));
1265         if (!dp)
1266                 return -ENOENT;
1267
1268         if (nla_len(va) < sizeof(struct ofp_header))
1269                 return -EINVAL;
1270         oh = nla_data(va);
1271
1272         sender.xid = oh->xid;
1273         sender.pid = info->snd_pid;
1274         sender.seq = info->snd_seq;
1275
1276         mutex_lock(&dp_mutex);
1277         err = fwd_control_input(dp->chain, &sender,
1278                                 nla_data(va), nla_len(va));
1279         mutex_unlock(&dp_mutex);
1280         return err;
1281 }
1282
1283 static struct nla_policy dp_genl_openflow_policy[DP_GENL_A_MAX + 1] = {
1284         [DP_GENL_A_DP_IDX] = { .type = NLA_U32 },
1285 };
1286
1287 static int desc_stats_dump(struct datapath *dp, void *state,
1288                             void *body, int *body_len)
1289 {
1290         struct ofp_desc_stats *ods = body;
1291         int n_bytes = sizeof *ods;
1292
1293         if (n_bytes > *body_len) {
1294                 return -ENOBUFS;
1295         }
1296         *body_len = n_bytes;
1297
1298         strncpy(ods->mfr_desc, mfr_desc, sizeof ods->mfr_desc);
1299         strncpy(ods->hw_desc, hw_desc, sizeof ods->hw_desc);
1300         strncpy(ods->sw_desc, sw_desc, sizeof ods->sw_desc);
1301         strncpy(ods->serial_num, serial_num, sizeof ods->serial_num);
1302
1303         return 0;
1304 }
1305
1306 struct flow_stats_state {
1307         int table_idx;
1308         struct sw_table_position position;
1309         const struct ofp_flow_stats_request *rq;
1310
1311         void *body;
1312         int bytes_used, bytes_allocated;
1313 };
1314
1315 static int flow_stats_init(struct datapath *dp, const void *body, int body_len,
1316                            void **state)
1317 {
1318         const struct ofp_flow_stats_request *fsr = body;
1319         struct flow_stats_state *s = kmalloc(sizeof *s, GFP_ATOMIC);
1320         if (!s)
1321                 return -ENOMEM;
1322         s->table_idx = fsr->table_id == 0xff ? 0 : fsr->table_id;
1323         memset(&s->position, 0, sizeof s->position);
1324         s->rq = fsr;
1325         *state = s;
1326         return 0;
1327 }
1328
1329 static int flow_stats_dump_callback(struct sw_flow *flow, void *private)
1330 {
1331         struct sw_flow_actions *sf_acts = rcu_dereference(flow->sf_acts);
1332         struct flow_stats_state *s = private;
1333         struct ofp_flow_stats *ofs;
1334         int length;
1335
1336         length = sizeof *ofs + sf_acts->actions_len;
1337         if (length + s->bytes_used > s->bytes_allocated)
1338                 return 1;
1339
1340         ofs = s->body + s->bytes_used;
1341         ofs->length          = htons(length);
1342         ofs->table_id        = s->table_idx;
1343         ofs->pad             = 0;
1344         ofs->match.wildcards = htonl(flow->key.wildcards);
1345         ofs->match.in_port   = flow->key.in_port;
1346         memcpy(ofs->match.dl_src, flow->key.dl_src, ETH_ALEN);
1347         memcpy(ofs->match.dl_dst, flow->key.dl_dst, ETH_ALEN);
1348         ofs->match.dl_vlan   = flow->key.dl_vlan;
1349         ofs->match.dl_type   = flow->key.dl_type;
1350         ofs->match.nw_src    = flow->key.nw_src;
1351         ofs->match.nw_dst    = flow->key.nw_dst;
1352         ofs->match.nw_proto  = flow->key.nw_proto;
1353         ofs->match.pad       = 0;
1354         ofs->match.tp_src    = flow->key.tp_src;
1355         ofs->match.tp_dst    = flow->key.tp_dst;
1356         ofs->duration        = htonl((jiffies - flow->init_time) / HZ);
1357         ofs->priority        = htons(flow->priority);
1358         ofs->idle_timeout    = htons(flow->idle_timeout);
1359         ofs->hard_timeout    = htons(flow->hard_timeout);
1360         memset(ofs->pad2, 0, sizeof ofs->pad2);
1361         ofs->packet_count    = cpu_to_be64(flow->packet_count);
1362         ofs->byte_count      = cpu_to_be64(flow->byte_count);
1363         memcpy(ofs->actions, sf_acts->actions, sf_acts->actions_len);
1364
1365         s->bytes_used += length;
1366         return 0;
1367 }
1368
1369 static int flow_stats_dump(struct datapath *dp, void *state,
1370                            void *body, int *body_len)
1371 {
1372         struct flow_stats_state *s = state;
1373         struct sw_flow_key match_key;
1374         int error = 0;
1375
1376         s->bytes_used = 0;
1377         s->bytes_allocated = *body_len;
1378         s->body = body;
1379
1380         flow_extract_match(&match_key, &s->rq->match);
1381         while (s->table_idx < dp->chain->n_tables
1382                && (s->rq->table_id == 0xff || s->rq->table_id == s->table_idx))
1383         {
1384                 struct sw_table *table = dp->chain->tables[s->table_idx];
1385
1386                 error = table->iterate(table, &match_key, &s->position,
1387                                        flow_stats_dump_callback, s);
1388                 if (error)
1389                         break;
1390
1391                 s->table_idx++;
1392                 memset(&s->position, 0, sizeof s->position);
1393         }
1394         *body_len = s->bytes_used;
1395
1396         /* If error is 0, we're done.
1397          * Otherwise, if some bytes were used, there are more flows to come.
1398          * Otherwise, we were not able to fit even a single flow in the body,
1399          * which indicates that we have a single flow with too many actions to
1400          * fit.  We won't ever make any progress at that rate, so give up. */
1401         return !error ? 0 : s->bytes_used ? 1 : -ENOMEM;
1402 }
1403
1404 static void flow_stats_done(void *state)
1405 {
1406         kfree(state);
1407 }
1408
1409 static int aggregate_stats_init(struct datapath *dp,
1410                                 const void *body, int body_len,
1411                                 void **state)
1412 {
1413         *state = (void *)body;
1414         return 0;
1415 }
1416
1417 static int aggregate_stats_dump_callback(struct sw_flow *flow, void *private)
1418 {
1419         struct ofp_aggregate_stats_reply *rpy = private;
1420         rpy->packet_count += flow->packet_count;
1421         rpy->byte_count += flow->byte_count;
1422         rpy->flow_count++;
1423         return 0;
1424 }
1425
1426 static int aggregate_stats_dump(struct datapath *dp, void *state,
1427                                 void *body, int *body_len)
1428 {
1429         struct ofp_aggregate_stats_request *rq = state;
1430         struct ofp_aggregate_stats_reply *rpy;
1431         struct sw_table_position position;
1432         struct sw_flow_key match_key;
1433         int table_idx;
1434
1435         if (*body_len < sizeof *rpy)
1436                 return -ENOBUFS;
1437         rpy = body;
1438         *body_len = sizeof *rpy;
1439
1440         memset(rpy, 0, sizeof *rpy);
1441
1442         flow_extract_match(&match_key, &rq->match);
1443         table_idx = rq->table_id == 0xff ? 0 : rq->table_id;
1444         memset(&position, 0, sizeof position);
1445         while (table_idx < dp->chain->n_tables
1446                && (rq->table_id == 0xff || rq->table_id == table_idx))
1447         {
1448                 struct sw_table *table = dp->chain->tables[table_idx];
1449                 int error;
1450
1451                 error = table->iterate(table, &match_key, &position,
1452                                        aggregate_stats_dump_callback, rpy);
1453                 if (error)
1454                         return error;
1455
1456                 table_idx++;
1457                 memset(&position, 0, sizeof position);
1458         }
1459
1460         rpy->packet_count = cpu_to_be64(rpy->packet_count);
1461         rpy->byte_count = cpu_to_be64(rpy->byte_count);
1462         rpy->flow_count = htonl(rpy->flow_count);
1463         return 0;
1464 }
1465
1466 static int table_stats_dump(struct datapath *dp, void *state,
1467                             void *body, int *body_len)
1468 {
1469         struct ofp_table_stats *ots;
1470         int n_bytes = dp->chain->n_tables * sizeof *ots;
1471         int i;
1472         if (n_bytes > *body_len)
1473                 return -ENOBUFS;
1474         *body_len = n_bytes;
1475         for (i = 0, ots = body; i < dp->chain->n_tables; i++, ots++) {
1476                 struct sw_table_stats stats;
1477                 dp->chain->tables[i]->stats(dp->chain->tables[i], &stats);
1478                 strncpy(ots->name, stats.name, sizeof ots->name);
1479                 ots->table_id = i;
1480                 ots->wildcards = htonl(stats.wildcards);
1481                 memset(ots->pad, 0, sizeof ots->pad);
1482                 ots->max_entries = htonl(stats.max_flows);
1483                 ots->active_count = htonl(stats.n_flows);
1484                 ots->lookup_count = cpu_to_be64(stats.n_lookup);
1485                 ots->matched_count = cpu_to_be64(stats.n_matched);
1486         }
1487         return 0;
1488 }
1489
1490 struct port_stats_state {
1491         int port;
1492 };
1493
1494 static int port_stats_init(struct datapath *dp, const void *body, int body_len,
1495                            void **state)
1496 {
1497         struct port_stats_state *s = kmalloc(sizeof *s, GFP_ATOMIC);
1498         if (!s)
1499                 return -ENOMEM;
1500         s->port = 0;
1501         *state = s;
1502         return 0;
1503 }
1504
1505 static int port_stats_dump(struct datapath *dp, void *state,
1506                            void *body, int *body_len)
1507 {
1508         struct port_stats_state *s = state;
1509         struct ofp_port_stats *ops;
1510         int n_ports, max_ports;
1511         int i;
1512
1513         max_ports = *body_len / sizeof *ops;
1514         if (!max_ports)
1515                 return -ENOMEM;
1516         ops = body;
1517
1518         n_ports = 0;
1519         for (i = s->port; i < DP_MAX_PORTS && n_ports < max_ports; i++) {
1520                 struct net_bridge_port *p = dp->ports[i];
1521                 struct net_device_stats *stats;
1522                 if (!p)
1523                         continue;
1524                 stats = p->dev->get_stats(p->dev);
1525                 ops->port_no = htons(p->port_no);
1526                 memset(ops->pad, 0, sizeof ops->pad);
1527                 ops->rx_packets   = cpu_to_be64(stats->rx_packets);
1528                 ops->tx_packets   = cpu_to_be64(stats->tx_packets);
1529                 ops->rx_bytes     = cpu_to_be64(stats->rx_bytes);
1530                 ops->tx_bytes     = cpu_to_be64(stats->tx_bytes);
1531                 ops->rx_dropped   = cpu_to_be64(stats->rx_dropped);
1532                 ops->tx_dropped   = cpu_to_be64(stats->tx_dropped);
1533                 ops->rx_errors    = cpu_to_be64(stats->rx_errors);
1534                 ops->tx_errors    = cpu_to_be64(stats->tx_errors);
1535                 ops->rx_frame_err = cpu_to_be64(stats->rx_frame_errors);
1536                 ops->rx_over_err  = cpu_to_be64(stats->rx_over_errors);
1537                 ops->rx_crc_err   = cpu_to_be64(stats->rx_crc_errors);
1538                 ops->collisions   = cpu_to_be64(stats->collisions);
1539                 n_ports++;
1540                 ops++;
1541         }
1542         s->port = i;
1543         *body_len = n_ports * sizeof *ops;
1544         return n_ports >= max_ports;
1545 }
1546
1547 static void port_stats_done(void *state)
1548 {
1549         kfree(state);
1550 }
1551
1552 struct stats_type {
1553         /* Minimum and maximum acceptable number of bytes in body member of
1554          * struct ofp_stats_request. */
1555         size_t min_body, max_body;
1556
1557         /* Prepares to dump some kind of statistics on 'dp'.  'body' and
1558          * 'body_len' are the 'body' member of the struct ofp_stats_request.
1559          * Returns zero if successful, otherwise a negative error code.
1560          * May initialize '*state' to state information.  May be null if no
1561          * initialization is required.*/
1562         int (*init)(struct datapath *dp, const void *body, int body_len,
1563                     void **state);
1564
1565         /* Dumps statistics for 'dp' into the '*body_len' bytes at 'body', and
1566          * modifies '*body_len' to reflect the number of bytes actually used.
1567          * ('body' will be transmitted as the 'body' member of struct
1568          * ofp_stats_reply.) */
1569         int (*dump)(struct datapath *dp, void *state,
1570                     void *body, int *body_len);
1571
1572         /* Cleans any state created by the init or dump functions.  May be null
1573          * if no cleanup is required. */
1574         void (*done)(void *state);
1575 };
1576
1577 static const struct stats_type stats[] = {
1578         [OFPST_DESC] = {
1579                 0,
1580                 0,
1581                 NULL,
1582                 desc_stats_dump,
1583                 NULL
1584         },
1585         [OFPST_FLOW] = {
1586                 sizeof(struct ofp_flow_stats_request),
1587                 sizeof(struct ofp_flow_stats_request),
1588                 flow_stats_init,
1589                 flow_stats_dump,
1590                 flow_stats_done
1591         },
1592         [OFPST_AGGREGATE] = {
1593                 sizeof(struct ofp_aggregate_stats_request),
1594                 sizeof(struct ofp_aggregate_stats_request),
1595                 aggregate_stats_init,
1596                 aggregate_stats_dump,
1597                 NULL
1598         },
1599         [OFPST_TABLE] = {
1600                 0,
1601                 0,
1602                 NULL,
1603                 table_stats_dump,
1604                 NULL
1605         },
1606         [OFPST_PORT] = {
1607                 0,
1608                 0,
1609                 port_stats_init,
1610                 port_stats_dump,
1611                 port_stats_done
1612         },
1613 };
1614
1615 static int
1616 dp_genl_openflow_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
1617 {
1618         struct datapath *dp;
1619         struct sender sender;
1620         const struct stats_type *s;
1621         struct ofp_stats_reply *osr;
1622         int dp_idx;
1623         int max_openflow_len, body_len;
1624         void *body;
1625         int err;
1626
1627         /* Set up the cleanup function for this dump.  Linux 2.6.20 and later
1628          * support setting up cleanup functions via the .doneit member of
1629          * struct genl_ops.  This kluge supports earlier versions also. */
1630         cb->done = dp_genl_openflow_done;
1631
1632         sender.pid = NETLINK_CB(cb->skb).pid;
1633         sender.seq = cb->nlh->nlmsg_seq;
1634         if (!cb->args[0]) {
1635                 struct nlattr *attrs[DP_GENL_A_MAX + 1];
1636                 struct ofp_stats_request *rq;
1637                 struct nlattr *va;
1638                 size_t len, body_len;
1639                 int type;
1640
1641                 err = nlmsg_parse(cb->nlh, GENL_HDRLEN, attrs, DP_GENL_A_MAX,
1642                                   dp_genl_openflow_policy);
1643                 if (err < 0)
1644                         return err;
1645
1646                 if (!attrs[DP_GENL_A_DP_IDX])
1647                         return -EINVAL;
1648                 dp_idx = nla_get_u16(attrs[DP_GENL_A_DP_IDX]);
1649                 dp = dp_get(dp_idx);
1650                 if (!dp)
1651                         return -ENOENT;
1652
1653                 va = attrs[DP_GENL_A_OPENFLOW];
1654                 len = nla_len(va);
1655                 if (!va || len < sizeof *rq)
1656                         return -EINVAL;
1657
1658                 rq = nla_data(va);
1659                 sender.xid = rq->header.xid;
1660                 type = ntohs(rq->type);
1661                 if (rq->header.version != OFP_VERSION) {
1662                         dp_send_error_msg(dp, &sender, OFPET_BAD_REQUEST,
1663                                           OFPBRC_BAD_VERSION, rq, len);
1664                         return -EINVAL;
1665                 }
1666                 if (rq->header.type != OFPT_STATS_REQUEST
1667                     || ntohs(rq->header.length) != len)
1668                         return -EINVAL;
1669
1670                 if (type >= ARRAY_SIZE(stats) || !stats[type].dump) {
1671                         dp_send_error_msg(dp, &sender, OFPET_BAD_REQUEST,
1672                                           OFPBRC_BAD_STAT, rq, len);
1673                         return -EINVAL;
1674                 }
1675
1676                 s = &stats[type];
1677                 body_len = len - offsetof(struct ofp_stats_request, body);
1678                 if (body_len < s->min_body || body_len > s->max_body)
1679                         return -EINVAL;
1680
1681                 cb->args[0] = 1;
1682                 cb->args[1] = dp_idx;
1683                 cb->args[2] = type;
1684                 cb->args[3] = rq->header.xid;
1685                 if (s->init) {
1686                         void *state;
1687                         err = s->init(dp, rq->body, body_len, &state);
1688                         if (err)
1689                                 return err;
1690                         cb->args[4] = (long) state;
1691                 }
1692         } else if (cb->args[0] == 1) {
1693                 sender.xid = cb->args[3];
1694                 dp_idx = cb->args[1];
1695                 s = &stats[cb->args[2]];
1696
1697                 dp = dp_get(dp_idx);
1698                 if (!dp)
1699                         return -ENOENT;
1700         } else {
1701                 return 0;
1702         }
1703
1704         osr = put_openflow_headers(dp, skb, OFPT_STATS_REPLY, &sender,
1705                                    &max_openflow_len);
1706         if (IS_ERR(osr))
1707                 return PTR_ERR(osr);
1708         osr->type = htons(s - stats);
1709         osr->flags = 0;
1710         resize_openflow_skb(skb, &osr->header, max_openflow_len);
1711         body = osr->body;
1712         body_len = max_openflow_len - offsetof(struct ofp_stats_reply, body);
1713
1714         err = s->dump(dp, (void *) cb->args[4], body, &body_len);
1715         if (err >= 0) {
1716                 if (!err)
1717                         cb->args[0] = 2;
1718                 else
1719                         osr->flags = ntohs(OFPSF_REPLY_MORE);
1720                 resize_openflow_skb(skb, &osr->header,
1721                                     (offsetof(struct ofp_stats_reply, body)
1722                                      + body_len));
1723                 err = skb->len;
1724         }
1725
1726         return err;
1727 }
1728
1729 static int
1730 dp_genl_openflow_done(struct netlink_callback *cb)
1731 {
1732         if (cb->args[0]) {
1733                 const struct stats_type *s = &stats[cb->args[2]];
1734                 if (s->done)
1735                         s->done((void *) cb->args[4]);
1736         }
1737         return 0;
1738 }
1739
1740 static struct genl_ops dp_genl_ops_openflow = {
1741         .cmd = DP_GENL_C_OPENFLOW,
1742         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1743         .policy = dp_genl_openflow_policy,
1744         .doit = dp_genl_openflow,
1745         .dumpit = dp_genl_openflow_dumpit,
1746 };
1747
1748 static struct genl_ops *dp_genl_all_ops[] = {
1749         /* Keep this operation first.  Generic Netlink dispatching
1750          * looks up operations with linear search, so we want it at the
1751          * front. */
1752         &dp_genl_ops_openflow,
1753
1754         &dp_genl_ops_add_dp,
1755         &dp_genl_ops_del_dp,
1756         &dp_genl_ops_query_dp,
1757         &dp_genl_ops_add_port,
1758         &dp_genl_ops_del_port,
1759 };
1760
1761 static int dp_init_netlink(void)
1762 {
1763         int err;
1764         int i;
1765
1766         err = genl_register_family(&dp_genl_family);
1767         if (err)
1768                 return err;
1769
1770         for (i = 0; i < ARRAY_SIZE(dp_genl_all_ops); i++) {
1771                 err = genl_register_ops(&dp_genl_family, dp_genl_all_ops[i]);
1772                 if (err)
1773                         goto err_unregister;
1774         }
1775
1776         strcpy(mc_group.name, "openflow");
1777         err = genl_register_mc_group(&dp_genl_family, &mc_group);
1778         if (err < 0)
1779                 goto err_unregister;
1780
1781         return 0;
1782
1783 err_unregister:
1784         genl_unregister_family(&dp_genl_family);
1785                 return err;
1786 }
1787
1788 static void dp_uninit_netlink(void)
1789 {
1790         genl_unregister_family(&dp_genl_family);
1791 }
1792
1793 /* Set the description strings if appropriate values are available from
1794  * the DMI. */
1795 static void set_desc(void)
1796 {
1797         const char *uuid = dmi_get_system_info(DMI_PRODUCT_UUID);
1798         const char *uptr = uuid + 24;
1799
1800         if (!uuid || *uuid == '\0' || strlen(uuid) != 36)
1801                 return;
1802
1803         /* We are only interested version 1 UUIDs, since the last six bytes
1804          * are an IEEE 802 MAC address. */
1805         if (uuid[14] != '1')
1806                 return;
1807
1808         /* Only set if the UUID is from Nicira. */
1809         if (strncmp(uptr, NICIRA_OUI_STR, strlen(NICIRA_OUI_STR)))
1810                 return;
1811
1812         strlcpy(mfr_desc, dmi_get_system_info(DMI_SYS_VENDOR), sizeof(mfr_desc));
1813         snprintf(hw_desc, sizeof(hw_desc), "%s %s",
1814                         dmi_get_system_info(DMI_PRODUCT_NAME),
1815                         dmi_get_system_info(DMI_PRODUCT_VERSION));
1816         strlcpy(serial_num, dmi_get_system_info(DMI_PRODUCT_SERIAL),
1817                         sizeof(serial_num));
1818 }
1819
1820 static int __init dp_init(void)
1821 {
1822         int err;
1823
1824         printk("OpenFlow %s, built "__DATE__" "__TIME__", "
1825                "protocol 0x%02x\n", VERSION BUILDNR, OFP_VERSION);
1826
1827         err = flow_init();
1828         if (err)
1829                 goto error;
1830
1831         err = register_netdevice_notifier(&dp_device_notifier);
1832         if (err)
1833                 goto error_flow_exit;
1834
1835         err = dp_init_netlink();
1836         if (err)
1837                 goto error_unreg_notifier;
1838
1839         /* Check if better descriptions of the switch are available than the
1840          * defaults. */
1841         set_desc();
1842
1843         /* Hook into callback used by the bridge to intercept packets.
1844          * Parasites we are. */
1845         if (br_handle_frame_hook)
1846                 printk("openflow: hijacking bridge hook\n");
1847         br_handle_frame_hook = dp_frame_hook;
1848
1849         return 0;
1850
1851 error_unreg_notifier:
1852         unregister_netdevice_notifier(&dp_device_notifier);
1853 error_flow_exit:
1854         flow_exit();
1855 error:
1856         printk(KERN_EMERG "openflow: failed to install!");
1857         return err;
1858 }
1859
1860 static void dp_cleanup(void)
1861 {
1862         fwd_exit();
1863         dp_uninit_netlink();
1864         unregister_netdevice_notifier(&dp_device_notifier);
1865         flow_exit();
1866         br_handle_frame_hook = NULL;
1867 }
1868
1869 module_init(dp_init);
1870 module_exit(dp_cleanup);
1871
1872 MODULE_DESCRIPTION("OpenFlow switching datapath");
1873 MODULE_AUTHOR("Copyright (c) 2007, 2008 The Board of Trustees of The Leland Stanford Junior University");
1874 MODULE_LICENSE("GPL");