pintos-os.org Git - openvswitch/blob - 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/module.h>
  10 #include <linux/if_arp.h>
  11 #include <linux/if_bridge.h>
  12 #include <linux/if_vlan.h>
  13 #include <linux/in.h>
  14 #include <net/genetlink.h>
  15 #include <linux/ip.h>
  16 #include <linux/delay.h>
  17 #include <linux/etherdevice.h>
  18 #include <linux/kernel.h>
  19 #include <linux/kthread.h>
  20 #include <linux/mutex.h>
  21 #include <linux/rtnetlink.h>
  22 #include <linux/rcupdate.h>
  23 #include <linux/version.h>
  24 #include <linux/ethtool.h>
  25 #include <linux/random.h>
  26 #include <asm/system.h>
  27 #include <linux/netfilter_bridge.h>
  28 #include <linux/inetdevice.h>
  29 #include <linux/list.h>
  30
  31 #include "openflow-netlink.h"
  32 #include "datapath.h"
  33 #include "table.h"
  34 #include "chain.h"
  35 #include "forward.h"
  36 #include "flow.h"
  37 #include "datapath_t.h"
  38
  39 #include "compat.h"
  40
  41
  42 /* Number of milliseconds between runs of the maintenance thread. */
  43 #define MAINT_SLEEP_MSECS 1000
  44
  45 #define BRIDGE_PORT_NO_FLOOD    0x00000001
  46
  47 #define UINT32_MAX                        4294967295U
  48
  49 struct net_bridge_port {
  50         u16     port_no;
  51         u32 flags;
  52         struct datapath *dp;
  53         struct net_device *dev;
  54         struct list_head node; /* Element in datapath.ports. */
  55 };
  56
  57 static struct genl_family dp_genl_family;
  58 static struct genl_multicast_group mc_group;
  59
  60 int dp_dev_setup(struct net_device *dev);
  61
  62 /* It's hard to imagine wanting more than one datapath, but... */
  63 #define DP_MAX 32
  64
  65 /* datapaths.  Protected on the read side by rcu_read_lock, on the write side
  66  * by dp_mutex.
  67  *
  68  * It is safe to access the datapath and net_bridge_port structures with just
  69  * the dp_mutex, but to access the chain you need to take the rcu_read_lock
  70  * also (because dp_mutex doesn't prevent flows from being destroyed).
  71  */
  72 static struct datapath *dps[DP_MAX];
  73 static DEFINE_MUTEX(dp_mutex);
  74
  75 static int dp_maint_func(void *data);
  76 static int send_port_status(struct net_bridge_port *p, uint8_t status);
  77
  78
  79 /* nla_unreserve - reduce amount of space reserved by nla_reserve
  80  * @skb: socket buffer from which to recover room
  81  * @nla: netlink attribute to adjust
  82  * @len: amount by which to reduce attribute payload
  83  *
  84  * Reduces amount of space reserved by a call to nla_reserve.
  85  *
  86  * No other attributes may be added between calling nla_reserve and this
  87  * function, since it will create a hole in the message.
  88  */
  89 void nla_unreserve(struct sk_buff *skb, struct nlattr *nla, int len)
  90 {
  91         skb->tail -= len;
  92         skb->len  -= len;
  93
  94         nla->nla_len -= len;
  95 }
  96
  97 /* Generates a unique datapath id.  It incorporates the datapath index
  98  * and a hardware address, if available.  If not, it generates a random
  99  * one.
 100  */
 101 static
 102 uint64_t gen_datapath_id(uint16_t dp_idx)
 103 {
 104         uint64_t id;
 105         int i;
 106         struct net_device *dev;
 107
 108         /* The top 16 bits are used to identify the datapath.  The lower 48 bits
 109          * use an interface address.  */
 110         id = (uint64_t)dp_idx << 48;
 111         if ((dev = dev_get_by_name(&init_net, "ctl0"))
 112                         || (dev = dev_get_by_name(&init_net, "eth0"))) {
 113                 for (i=0; i<ETH_ALEN; i++) {
 114                         id |= (uint64_t)dev->dev_addr[i] << (8*(ETH_ALEN-1 - i));
 115                 }
 116                 dev_put(dev);
 117         } else {
 118                 /* Randomly choose the lower 48 bits if we cannot find an
 119                  * address and mark the most significant bit to indicate that
 120                  * this was randomly generated. */
 121                 uint8_t rand[ETH_ALEN];
 122                 get_random_bytes(rand, ETH_ALEN);
 123                 id |= (uint64_t)1 << 63;
 124                 for (i=0; i<ETH_ALEN; i++) {
 125                         id |= (uint64_t)rand[i] << (8*(ETH_ALEN-1 - i));
 126                 }
 127         }
 128
 129         return id;
 130 }
 131
 132 /* Creates a new datapath numbered 'dp_idx'.  Returns 0 for success or a
 133  * negative error code.
 134  *
 135  * Not called with any locks. */
 136 static int new_dp(int dp_idx)
 137 {
 138         struct datapath *dp;
 139         int err;
 140
 141         if (dp_idx < 0 || dp_idx >= DP_MAX)
 142                 return -EINVAL;
 143
 144         if (!try_module_get(THIS_MODULE))
 145                 return -ENODEV;
 146
 147         mutex_lock(&dp_mutex);
 148         dp = rcu_dereference(dps[dp_idx]);
 149         if (dp != NULL) {
 150                 err = -EEXIST;
 151                 goto err_unlock;
 152         }
 153
 154         err = -ENOMEM;
 155         dp = kzalloc(sizeof *dp, GFP_KERNEL);
 156         if (dp == NULL)
 157                 goto err_unlock;
 158
 159         dp->dp_idx = dp_idx;
 160         dp->id = gen_datapath_id(dp_idx);
 161         dp->chain = chain_create(dp);
 162         if (dp->chain == NULL)
 163                 goto err_free_dp;
 164         INIT_LIST_HEAD(&dp->port_list);
 165
 166 #if 0
 167         /* Setup our "of" device */
 168         dp->dev.priv = dp;
 169         rtnl_lock();
 170         err = dp_dev_setup(&dp->dev);
 171         rtnl_unlock();
 172         if (err != 0)
 173                 printk("datapath: problem setting up 'of' device\n");
 174 #endif
 175
 176         dp->miss_send_len = OFP_DEFAULT_MISS_SEND_LEN;
 177
 178         dp->dp_task = kthread_run(dp_maint_func, dp, "dp%d", dp_idx);
 179         if (IS_ERR(dp->dp_task))
 180                 goto err_free_dp;
 181
 182         rcu_assign_pointer(dps[dp_idx], dp);
 183         mutex_unlock(&dp_mutex);
 184
 185         return 0;
 186
 187 err_free_dp:
 188         kfree(dp);
 189 err_unlock:
 190         mutex_unlock(&dp_mutex);
 191         module_put(THIS_MODULE);
 192                 return err;
 193 }
 194
 195 /* Find and return a free port number under 'dp'.  Called under dp_mutex. */
 196 static int find_portno(struct datapath *dp)
 197 {
 198         int i;
 199         for (i = 0; i < OFPP_MAX; i++)
 200                 if (dp->ports[i] == NULL)
 201                         return i;
 202         return -EXFULL;
 203 }
 204
 205 static struct net_bridge_port *new_nbp(struct datapath *dp,
 206                                                                            struct net_device *dev)
 207 {
 208         struct net_bridge_port *p;
 209         int port_no;
 210
 211         port_no = find_portno(dp);
 212         if (port_no < 0)
 213                 return ERR_PTR(port_no);
 214
 215         p = kzalloc(sizeof(*p), GFP_KERNEL);
 216         if (p == NULL)
 217                 return ERR_PTR(-ENOMEM);
 218
 219         p->dp = dp;
 220         dev_hold(dev);
 221         p->dev = dev;
 222         p->port_no = port_no;
 223
 224         return p;
 225 }
 226
 227 /* Called with dp_mutex. */
 228 int add_switch_port(struct datapath *dp, struct net_device *dev)
 229 {
 230         struct net_bridge_port *p;
 231
 232         if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER)
 233                 return -EINVAL;
 234
 235         if (dev->br_port != NULL)
 236                 return -EBUSY;
 237
 238         p = new_nbp(dp, dev);
 239         if (IS_ERR(p))
 240                 return PTR_ERR(p);
 241
 242         dev_hold(dev);
 243         rcu_assign_pointer(dev->br_port, p);
 244         rtnl_lock();
 245         dev_set_promiscuity(dev, 1);
 246         rtnl_unlock();
 247
 248         rcu_assign_pointer(dp->ports[p->port_no], p);
 249         list_add_rcu(&p->node, &dp->port_list);
 250
 251         /* Notify the ctlpath that this port has been added */
 252         send_port_status(p, OFPPR_ADD);
 253
 254         return 0;
 255 }
 256
 257 /* Delete 'p' from switch.
 258  * Called with dp_mutex. */
 259 static int del_switch_port(struct net_bridge_port *p)
 260 {
 261         /* First drop references to device. */
 262         rtnl_lock();
 263         dev_set_promiscuity(p->dev, -1);
 264         rtnl_unlock();
 265         list_del_rcu(&p->node);
 266         rcu_assign_pointer(p->dp->ports[p->port_no], NULL);
 267         rcu_assign_pointer(p->dev->br_port, NULL);
 268
 269         /* Then wait until no one is still using it, and destroy it. */
 270         synchronize_rcu();
 271
 272         /* Notify the ctlpath that this port no longer exists */
 273         send_port_status(p, OFPPR_DELETE);
 274
 275         dev_put(p->dev);
 276         kfree(p);
 277
 278         return 0;
 279 }
 280
 281 /* Called with dp_mutex. */
 282 static void del_dp(struct datapath *dp)
 283 {
 284         struct net_bridge_port *p, *n;
 285
 286 #if 0
 287         /* Unregister the "of" device of this dp */
 288         rtnl_lock();
 289         unregister_netdevice(&dp->dev);
 290         rtnl_unlock();
 291 #endif
 292
 293         kthread_stop(dp->dp_task);
 294
 295         /* Drop references to DP. */
 296         list_for_each_entry_safe (p, n, &dp->port_list, node)
 297                 del_switch_port(p);
 298         rcu_assign_pointer(dps[dp->dp_idx], NULL);
 299
 300         /* Wait until no longer in use, then destroy it. */
 301         synchronize_rcu();
 302         chain_destroy(dp->chain);
 303         kfree(dp);
 304         module_put(THIS_MODULE);
 305 }
 306
 307 static int dp_maint_func(void *data)
 308 {
 309         struct datapath *dp = (struct datapath *) data;
 310
 311         while (!kthread_should_stop()) {
 312 #if 1
 313                 chain_timeout(dp->chain);
 314 #else
 315                 int count = chain_timeout(dp->chain);
 316                 chain_print_stats(dp->chain);
 317                 if (count)
 318                         printk("%d flows timed out\n", count);
 319 #endif
 320                 msleep_interruptible(MAINT_SLEEP_MSECS);
 321         }
 322
 323         return 0;
 324 }
 325
 326 /*
 327  * Used as br_handle_frame_hook.  (Cannot run bridge at the same time, even on
 328  * different set of devices!)  Returns 0 if *pskb should be processed further,
 329  * 1 if *pskb is handled. */
 330 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
 331 /* Called with rcu_read_lock. */
 332 static struct sk_buff *dp_frame_hook(struct net_bridge_port *p,
 333                                          struct sk_buff *skb)
 334 {
 335         struct ethhdr *eh = eth_hdr(skb);
 336         struct sk_buff *skb_local = NULL;
 337
 338
 339         if (compare_ether_addr(eh->h_dest, skb->dev->dev_addr) == 0)
 340                 return skb;
 341
 342         if (is_broadcast_ether_addr(eh->h_dest)
 343                                 || is_multicast_ether_addr(eh->h_dest)
 344                                 || is_local_ether_addr(eh->h_dest))
 345                 skb_local = skb_clone(skb, GFP_ATOMIC);
 346
 347         /* Push the Ethernet header back on. */
 348         if (skb->protocol == htons(ETH_P_8021Q))
 349                 skb_push(skb, VLAN_ETH_HLEN);
 350         else
 351                 skb_push(skb, ETH_HLEN);
 352
 353         fwd_port_input(p->dp->chain, skb, p->port_no);
 354
 355         return skb_local;
 356 }
 357 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
 358 static int dp_frame_hook(struct net_bridge_port *p, struct sk_buff **pskb)
 359 {
 360         /* Push the Ethernet header back on. */
 361         if ((*pskb)->protocol == htons(ETH_P_8021Q))
 362                 skb_push(*pskb, VLAN_ETH_HLEN);
 363         else
 364                 skb_push(*pskb, ETH_HLEN);
 365
 366         fwd_port_input(p->dp->chain, *pskb, p->port_no);
 367         return 1;
 368 }
 369 #else
 370 /* NB: This has only been tested on 2.4.35 */
 371
 372 /* Called without any locks (?) */
 373 static void dp_frame_hook(struct sk_buff *skb)
 374 {
 375         struct net_bridge_port *p = skb->dev->br_port;
 376
 377         /* Push the Ethernet header back on. */
 378         if (skb->protocol == htons(ETH_P_8021Q))
 379                 skb_push(skb, VLAN_ETH_HLEN);
 380         else
 381                 skb_push(skb, ETH_HLEN);
 382
 383         if (p) {
 384                 rcu_read_lock();
 385                 fwd_port_input(p->dp->chain, skb, p->port_no);
 386                 rcu_read_unlock();
 387         } else
 388                 kfree_skb(skb);
 389 }
 390 #endif
 391
 392 /* Forwarding output path.
 393  * Based on net/bridge/br_forward.c. */
 394
 395 /* Don't forward packets to originating port or with flooding disabled */
 396 static inline int should_deliver(const struct net_bridge_port *p,
 397                         const struct sk_buff *skb)
 398 {
 399         if ((skb->dev == p->dev) || (p->flags & BRIDGE_PORT_NO_FLOOD)) {
 400                 return 0;
 401         }
 402
 403         return 1;
 404 }
 405
 406 static inline unsigned packet_length(const struct sk_buff *skb)
 407 {
 408         int length = skb->len - ETH_HLEN;
 409         if (skb->protocol == htons(ETH_P_8021Q))
 410                 length -= VLAN_HLEN;
 411         return length;
 412 }
 413
 414 static int
 415 flood(struct datapath *dp, struct sk_buff *skb)
 416 {
 417         struct net_bridge_port *p;
 418         int prev_port;
 419
 420         prev_port = -1;
 421         list_for_each_entry_rcu (p, &dp->port_list, node) {
 422                 if (!should_deliver(p, skb))
 423                         continue;
 424                 if (prev_port != -1) {
 425                         struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
 426                         if (!clone) {
 427                                 kfree_skb(skb);
 428                                 return -ENOMEM;
 429                         }
 430                         dp_output_port(dp, clone, prev_port);
 431                 }
 432                 prev_port = p->port_no;
 433         }
 434         if (prev_port != -1)
 435                 dp_output_port(dp, skb, prev_port);
 436         else
 437                 kfree_skb(skb);
 438
 439         return 0;
 440 }
 441
 442 /* Marks 'skb' as having originated from 'in_port' in 'dp'.
 443    FIXME: how are devices reference counted? */
 444 int dp_set_origin(struct datapath *dp, uint16_t in_port,
 445                            struct sk_buff *skb)
 446 {
 447         if (in_port < OFPP_MAX && dp->ports[in_port]) {
 448                 skb->dev = dp->ports[in_port]->dev;
 449                 return 0;
 450         }
 451         return -ENOENT;
 452 }
 453
 454 /* Takes ownership of 'skb' and transmits it to 'out_port' on 'dp'.
 455  */
 456 int dp_output_port(struct datapath *dp, struct sk_buff *skb, int out_port)
 457 {
 458         struct net_bridge_port *p;
 459         int len = skb->len;
 460
 461         BUG_ON(!skb);
 462         if (out_port == OFPP_FLOOD)
 463                 return flood(dp, skb);
 464         else if (out_port == OFPP_CONTROLLER)
 465                 return dp_output_control(dp, skb, fwd_save_skb(skb), 0,
 466                                                   OFPR_ACTION);
 467         else if (out_port >= OFPP_MAX)
 468                 goto bad_port;
 469
 470         p = dp->ports[out_port];
 471         if (p == NULL)
 472                 goto bad_port;
 473
 474         skb->dev = p->dev;
 475         if (packet_length(skb) > skb->dev->mtu) {
 476                 printk("dropped over-mtu packet: %d > %d\n",
 477                                         packet_length(skb), skb->dev->mtu);
 478                 kfree_skb(skb);
 479                 return -E2BIG;
 480         }
 481
 482         dev_queue_xmit(skb);
 483
 484         return len;
 485
 486 bad_port:
 487         kfree_skb(skb);
 488         if (net_ratelimit())
 489                 printk("can't forward to bad port %d\n", out_port);
 490         return -ENOENT;
 491 }
 492
 493 /* Takes ownership of 'skb' and transmits it to 'dp''s control path.  If
 494  * 'buffer_id' != -1, then only the first 64 bytes of 'skb' are sent;
 495  * otherwise, all of 'skb' is sent.  'reason' indicates why 'skb' is being
 496  * sent. 'max_len' sets the maximum number of bytes that the caller
 497  * wants to be sent; a value of 0 indicates the entire packet should be
 498  * sent. */
 499 int
 500 dp_output_control(struct datapath *dp, struct sk_buff *skb,
 501                            uint32_t buffer_id, size_t max_len, int reason)
 502 {
 503         /* FIXME? packet_rcv_spkt in net/packet/af_packet.c does some stuff
 504            that we should possibly be doing here too. */
 505         /* FIXME?  Can we avoid creating a new skbuff in the case where we
 506          * forward the whole packet? */
 507         struct sk_buff *f_skb;
 508         struct nlattr *attr;
 509         struct ofp_packet_in *opi;
 510         size_t opi_len;
 511         size_t len, fwd_len;
 512         void *data;
 513         int err = -ENOMEM;
 514
 515         fwd_len = skb->len;
 516         if ((buffer_id != (uint32_t) -1) && max_len)
 517                 fwd_len = min(fwd_len, max_len);
 518
 519         len = nla_total_size(offsetof(struct ofp_packet_in, data) + fwd_len)
 520                                 + nla_total_size(sizeof(uint32_t));
 521
 522         f_skb = genlmsg_new(len, GFP_ATOMIC);
 523         if (!f_skb)
 524                 goto error_free_skb;
 525
 526         data = genlmsg_put(f_skb, 0, 0, &dp_genl_family, 0,
 527                                 DP_GENL_C_OPENFLOW);
 528         if (data == NULL)
 529                 goto error_free_f_skb;
 530
 531         NLA_PUT_U32(f_skb, DP_GENL_A_DP_IDX, dp->dp_idx);
 532
 533         opi_len = offsetof(struct ofp_packet_in, data) + fwd_len;
 534         attr = nla_reserve(f_skb, DP_GENL_A_OPENFLOW, opi_len);
 535         if (!attr)
 536                 goto error_free_f_skb;
 537         opi = nla_data(attr);
 538         opi->header.version = OFP_VERSION;
 539         opi->header.type    = OFPT_PACKET_IN;
 540         opi->header.length  = htons(opi_len);
 541         opi->header.xid     = htonl(0);
 542
 543         opi->buffer_id      = htonl(buffer_id);
 544         opi->total_len      = htons(skb->len);
 545         opi->in_port        = htons(skb->dev->br_port->port_no);
 546         opi->reason         = reason;
 547         opi->pad            = 0;
 548         SKB_LINEAR_ASSERT(skb);
 549         memcpy(opi->data, skb_mac_header(skb), fwd_len);
 550
 551         err = genlmsg_end(f_skb, data);
 552         if (err < 0)
 553                 goto error_free_f_skb;
 554
 555         err = genlmsg_multicast(f_skb, 0, mc_group.id, GFP_ATOMIC);
 556         if (err && net_ratelimit())
 557                 printk(KERN_WARNING "dp_output_control: genlmsg_multicast failed: %d\n", err);
 558
 559         kfree_skb(skb);
 560
 561         return err;
 562
 563 nla_put_failure:
 564 error_free_f_skb:
 565         nlmsg_free(f_skb);
 566 error_free_skb:
 567         kfree_skb(skb);
 568         if (net_ratelimit())
 569                 printk(KERN_ERR "dp_output_control: failed to send: %d\n", err);
 570         return err;
 571 }
 572
 573 static void fill_port_desc(struct net_bridge_port *p, struct ofp_phy_port *desc)
 574 {
 575         desc->port_no = htons(p->port_no);
 576         strncpy(desc->name, p->dev->name, OFP_MAX_PORT_NAME_LEN);
 577         desc->name[OFP_MAX_PORT_NAME_LEN-1] = '\0';
 578         memcpy(desc->hw_addr, p->dev->dev_addr, ETH_ALEN);
 579         desc->flags = htonl(p->flags);
 580         desc->features = 0;
 581         desc->speed = 0;
 582
 583 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,24)
 584         if (p->dev->ethtool_ops && p->dev->ethtool_ops->get_settings) {
 585                 struct ethtool_cmd ecmd = { .cmd = ETHTOOL_GSET };
 586
 587                 if (!p->dev->ethtool_ops->get_settings(p->dev, &ecmd)) {
 588                         if (ecmd.supported & SUPPORTED_10baseT_Half)
 589                                 desc->features |= OFPPF_10MB_HD;
 590                         if (ecmd.supported & SUPPORTED_10baseT_Full)
 591                                 desc->features |= OFPPF_10MB_FD;
 592                         if (ecmd.supported & SUPPORTED_100baseT_Half)
 593                                 desc->features |= OFPPF_100MB_HD;
 594                         if (ecmd.supported & SUPPORTED_100baseT_Full)
 595                                 desc->features |= OFPPF_100MB_FD;
 596                         if (ecmd.supported & SUPPORTED_1000baseT_Half)
 597                                 desc->features |= OFPPF_1GB_HD;
 598                         if (ecmd.supported & SUPPORTED_1000baseT_Full)
 599                                 desc->features |= OFPPF_1GB_FD;
 600                         /* 10Gbps half-duplex doesn't exist... */
 601                         if (ecmd.supported & SUPPORTED_10000baseT_Full)
 602                                 desc->features |= OFPPF_10GB_FD;
 603
 604                         desc->features = htonl(desc->features);
 605                         desc->speed = htonl(ecmd.speed);
 606                 }
 607         }
 608 #endif
 609 }
 610
 611 static int
 612 fill_data_hello(struct datapath *dp, struct ofp_data_hello *odh)
 613 {
 614         struct net_bridge_port *p;
 615         int port_count = 0;
 616
 617         odh->header.version = OFP_VERSION;
 618         odh->header.type    = OFPT_DATA_HELLO;
 619         odh->header.xid     = htonl(0);
 620         odh->datapath_id    = cpu_to_be64(dp->id);
 621
 622         odh->n_exact        = htonl(2 * TABLE_HASH_MAX_FLOWS);
 623         odh->n_mac_only     = htonl(TABLE_MAC_MAX_FLOWS);
 624         odh->n_compression  = 0;                                           /* Not supported */
 625         odh->n_general      = htonl(TABLE_LINEAR_MAX_FLOWS);
 626         odh->buffer_mb      = htonl(UINT32_MAX);
 627         odh->n_buffers      = htonl(N_PKT_BUFFERS);
 628         odh->capabilities   = htonl(OFP_SUPPORTED_CAPABILITIES);
 629         odh->actions        = htonl(OFP_SUPPORTED_ACTIONS);
 630         odh->miss_send_len  = htons(dp->miss_send_len);
 631
 632         list_for_each_entry_rcu (p, &dp->port_list, node) {
 633                 fill_port_desc(p, &odh->ports[port_count]);
 634                 port_count++;
 635         }
 636
 637         return port_count;
 638 }
 639
 640 int
 641 dp_send_hello(struct datapath *dp)
 642 {
 643         struct sk_buff *skb;
 644         struct nlattr *attr;
 645         struct ofp_data_hello *odh;
 646         size_t odh_max_len, odh_len, port_max_len, len;
 647         void *data;
 648         int err = -ENOMEM;
 649         int port_count;
 650
 651
 652         /* Overallocate, since we can't reliably determine the number of
 653          * ports a priori. */
 654         port_max_len = sizeof(struct ofp_phy_port) * OFPP_MAX;
 655
 656         len = nla_total_size(sizeof(*odh) + port_max_len)
 657                                 + nla_total_size(sizeof(uint32_t));
 658
 659         skb = genlmsg_new(len, GFP_ATOMIC);
 660         if (!skb) {
 661                 if (net_ratelimit())
 662                         printk("dp_send_hello: genlmsg_new failed\n");
 663                 goto error;
 664         }
 665
 666         data = genlmsg_put(skb, 0, 0, &dp_genl_family, 0,
 667                            DP_GENL_C_OPENFLOW);
 668         if (data == NULL) {
 669                 if (net_ratelimit())
 670                         printk("dp_send_hello: genlmsg_put failed\n");
 671                 goto error;
 672         }
 673
 674         NLA_PUT_U32(skb, DP_GENL_A_DP_IDX, dp->dp_idx);
 675
 676         odh_max_len = sizeof(*odh) + port_max_len;
 677         attr = nla_reserve(skb, DP_GENL_A_OPENFLOW, odh_max_len);
 678         if (!attr) {
 679                 if (net_ratelimit())
 680                         printk("dp_send_hello: nla_reserve failed\n");
 681                 goto error;
 682         }
 683         odh = nla_data(attr);
 684         port_count = fill_data_hello(dp, odh);
 685
 686         /* Only now that we know how many ports we've added can we say
 687          * say something about the length. */
 688         odh_len = sizeof(*odh) + (sizeof(struct ofp_phy_port) * port_count);
 689         odh->header.length = htons(odh_len);
 690
 691         /* Take back the unused part that was reserved */
 692         nla_unreserve(skb, attr, (odh_max_len - odh_len));
 693
 694         err = genlmsg_end(skb, data);
 695         if (err < 0) {
 696                 if (net_ratelimit())
 697                         printk("dp_send_hello: genlmsg_end failed\n");
 698                 goto error;
 699         }
 700
 701         err = genlmsg_multicast(skb, 0, mc_group.id, GFP_ATOMIC);
 702         if (err && net_ratelimit())
 703                 printk(KERN_WARNING "dp_send_hello: genlmsg_multicast failed: %d\n", err);
 704
 705         return err;
 706
 707 nla_put_failure:
 708 error:
 709         kfree_skb(skb);
 710         if (net_ratelimit())
 711                 printk(KERN_ERR "dp_send_hello: failed to send: %d\n", err);
 712         return err;
 713 }
 714
 715 int
 716 dp_update_port_flags(struct datapath *dp, const struct ofp_phy_port *opp)
 717 {
 718         struct net_bridge_port *p;
 719
 720         p = dp->ports[htons(opp->port_no)];
 721
 722         /* Make sure the port id hasn't changed since this was sent */
 723         if (!p || memcmp(opp->hw_addr, p->dev->dev_addr, ETH_ALEN) != 0)
 724                 return -1;
 725
 726         p->flags = htonl(opp->flags);
 727
 728         return 0;
 729 }
 730
 731
 732 static int
 733 send_port_status(struct net_bridge_port *p, uint8_t status)
 734 {
 735         struct sk_buff *skb;
 736         struct nlattr *attr;
 737         struct ofp_port_status *ops;
 738         void *data;
 739         int err = -ENOMEM;
 740
 741
 742         skb = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
 743         if (!skb) {
 744                 if (net_ratelimit())
 745                         printk("send_port_status: genlmsg_new failed\n");
 746                 goto error;
 747         }
 748
 749         data = genlmsg_put(skb, 0, 0, &dp_genl_family, 0,
 750                            DP_GENL_C_OPENFLOW);
 751         if (data == NULL) {
 752                 if (net_ratelimit())
 753                         printk("send_port_status: genlmsg_put failed\n");
 754                 goto error;
 755         }
 756
 757         NLA_PUT_U32(skb, DP_GENL_A_DP_IDX, p->dp->dp_idx);
 758
 759         attr = nla_reserve(skb, DP_GENL_A_OPENFLOW, sizeof(*ops));
 760         if (!attr) {
 761                 if (net_ratelimit())
 762                         printk("send_port_status: nla_reserve failed\n");
 763                 goto error;
 764         }
 765
 766         ops = nla_data(attr);
 767         ops->header.version = OFP_VERSION;
 768         ops->header.type    = OFPT_PORT_STATUS;
 769         ops->header.length  = htons(sizeof(*ops));
 770         ops->header.xid     = htonl(0);
 771
 772         ops->reason         = status;
 773         fill_port_desc(p, &ops->desc);
 774
 775         err = genlmsg_end(skb, data);
 776         if (err < 0) {
 777                 if (net_ratelimit())
 778                         printk("send_port_status: genlmsg_end failed\n");
 779                 goto error;
 780         }
 781
 782         err = genlmsg_multicast(skb, 0, mc_group.id, GFP_ATOMIC);
 783         if (err && net_ratelimit())
 784                 printk(KERN_WARNING "send_port_status: genlmsg_multicast failed: %d\n", err);
 785
 786         return err;
 787
 788 nla_put_failure:
 789 error:
 790         kfree_skb(skb);
 791         if (net_ratelimit())
 792                 printk(KERN_ERR "send_port_status: failed to send: %d\n", err);
 793         return err;
 794 }
 795
 796 int
 797 dp_send_flow_expired(struct datapath *dp, struct sw_flow *flow)
 798 {
 799         struct sk_buff *skb;
 800         struct nlattr *attr;
 801         struct ofp_flow_expired *ofe;
 802         void *data;
 803         unsigned long duration_j;
 804         int err = -ENOMEM;
 805
 806
 807         skb = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
 808         if (!skb) {
 809                 if (net_ratelimit())
 810                         printk("dp_send_flow_expired: genlmsg_new failed\n");
 811                 goto error;
 812         }
 813
 814         data = genlmsg_put(skb, 0, 0, &dp_genl_family, 0,
 815                            DP_GENL_C_OPENFLOW);
 816         if (data == NULL) {
 817                 if (net_ratelimit())
 818                         printk("dp_send_flow_expired: genlmsg_put failed\n");
 819                 goto error;
 820         }
 821
 822         NLA_PUT_U32(skb, DP_GENL_A_DP_IDX, dp->dp_idx);
 823
 824         attr = nla_reserve(skb, DP_GENL_A_OPENFLOW, sizeof(*ofe));
 825         if (!attr) {
 826                 if (net_ratelimit())
 827                         printk("dp_send_flow_expired: nla_reserve failed\n");
 828                 goto error;
 829         }
 830
 831         ofe = nla_data(attr);
 832         ofe->header.version = OFP_VERSION;
 833         ofe->header.type    = OFPT_FLOW_EXPIRED;
 834         ofe->header.length  = htons(sizeof(*ofe));
 835         ofe->header.xid     = htonl(0);
 836
 837         flow_fill_match(&ofe->match, &flow->key);
 838         duration_j = (flow->timeout - HZ * flow->max_idle) - flow->init_time;
 839         ofe->duration   = htonl(duration_j / HZ);
 840         ofe->packet_count   = cpu_to_be64(flow->packet_count);
 841         ofe->byte_count     = cpu_to_be64(flow->byte_count);
 842
 843         err = genlmsg_end(skb, data);
 844         if (err < 0) {
 845                 if (net_ratelimit())
 846                         printk("dp_send_flow_expired: genlmsg_end failed\n");
 847                 goto error;
 848         }
 849
 850         err = genlmsg_multicast(skb, 0, mc_group.id, GFP_ATOMIC);
 851         if (err && net_ratelimit())
 852                 printk(KERN_WARNING "send_flow_expired: genlmsg_multicast failed: %d\n", err);
 853
 854         return err;
 855
 856 nla_put_failure:
 857 error:
 858         kfree_skb(skb);
 859         if (net_ratelimit())
 860                 printk(KERN_ERR "send_flow_expired: failed to send: %d\n", err);
 861         return err;
 862 }
 863
 864 /* Generic Netlink interface.
 865  *
 866  * See netlink(7) for an introduction to netlink.  See
 867  * http://linux-net.osdl.org/index.php/Netlink for more information and
 868  * pointers on how to work with netlink and Generic Netlink in the kernel and
 869  * in userspace. */
 870
 871 static struct genl_family dp_genl_family = {
 872         .id = GENL_ID_GENERATE,
 873         .hdrsize = 0,
 874         .name = DP_GENL_FAMILY_NAME,
 875         .version = 1,
 876         .maxattr = DP_GENL_A_MAX,
 877 };
 878
 879 /* Attribute policy: what each attribute may contain.  */
 880 static struct nla_policy dp_genl_policy[DP_GENL_A_MAX + 1] = {
 881         [DP_GENL_A_DP_IDX] = { .type = NLA_U32 },
 882         [DP_GENL_A_MC_GROUP] = { .type = NLA_U32 },
 883         [DP_GENL_A_PORTNAME] = { .type = NLA_STRING }
 884 };
 885
 886 static int dp_genl_add(struct sk_buff *skb, struct genl_info *info)
 887 {
 888         if (!info->attrs[DP_GENL_A_DP_IDX])
 889                 return -EINVAL;
 890
 891         return new_dp(nla_get_u32(info->attrs[DP_GENL_A_DP_IDX]));
 892 }
 893
 894 static struct genl_ops dp_genl_ops_add_dp = {
 895         .cmd = DP_GENL_C_ADD_DP,
 896         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
 897         .policy = dp_genl_policy,
 898         .doit = dp_genl_add,
 899         .dumpit = NULL,
 900 };
 901
 902 struct datapath *dp_get(int dp_idx)
 903 {
 904         if (dp_idx < 0 || dp_idx > DP_MAX)
 905                 return NULL;
 906         return rcu_dereference(dps[dp_idx]);
 907 }
 908
 909 static int dp_genl_del(struct sk_buff *skb, struct genl_info *info)
 910 {
 911         struct datapath *dp;
 912         int err;
 913
 914         if (!info->attrs[DP_GENL_A_DP_IDX])
 915                 return -EINVAL;
 916
 917         mutex_lock(&dp_mutex);
 918         dp = dp_get(nla_get_u32((info->attrs[DP_GENL_A_DP_IDX])));
 919         if (!dp)
 920                 err = -ENOENT;
 921         else {
 922                 del_dp(dp);
 923                 err = 0;
 924         }
 925         mutex_unlock(&dp_mutex);
 926         return err;
 927 }
 928
 929 static struct genl_ops dp_genl_ops_del_dp = {
 930         .cmd = DP_GENL_C_DEL_DP,
 931         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
 932         .policy = dp_genl_policy,
 933         .doit = dp_genl_del,
 934         .dumpit = NULL,
 935 };
 936
 937 /* Queries a datapath for related information.  Currently the only relevant
 938  * information is the datapath's multicast group ID.  Really we want one
 939  * multicast group per datapath, but because of locking issues[*] we can't
 940  * easily get one.  Thus, every datapath will currently return the same
 941  * global multicast group ID, but in the future it would be nice to fix that.
 942  *
 943  * [*] dp_genl_add, to add a new datapath, is called under the genl_lock
 944  *       mutex, and genl_register_mc_group, called to acquire a new multicast
 945  *       group ID, also acquires genl_lock, thus deadlock.
 946  */
 947 static int dp_genl_query(struct sk_buff *skb, struct genl_info *info)
 948 {
 949         struct datapath *dp;
 950         struct sk_buff *ans_skb = NULL;
 951         int dp_idx;
 952         int err = -ENOMEM;
 953
 954         if (!info->attrs[DP_GENL_A_DP_IDX])
 955                 return -EINVAL;
 956
 957         rcu_read_lock();
 958         dp_idx = nla_get_u32((info->attrs[DP_GENL_A_DP_IDX]));
 959         dp = dp_get(dp_idx);
 960         if (!dp)
 961                 err = -ENOENT;
 962         else {
 963                 void *data;
 964                 ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 965                 if (!ans_skb) {
 966                         err = -ENOMEM;
 967                         goto err;
 968                 }
 969                 data = genlmsg_put_reply(ans_skb, info, &dp_genl_family,
 970                                          0, DP_GENL_C_QUERY_DP);
 971                 if (data == NULL) {
 972                         err = -ENOMEM;
 973                         goto err;
 974                 }
 975                 NLA_PUT_U32(ans_skb, DP_GENL_A_DP_IDX, dp_idx);
 976                 NLA_PUT_U32(ans_skb, DP_GENL_A_MC_GROUP, mc_group.id);
 977
 978                 genlmsg_end(ans_skb, data);
 979                 err = genlmsg_reply(ans_skb, info);
 980                 if (!err)
 981                         ans_skb = NULL;
 982         }
 983 err:
 984 nla_put_failure:
 985         if (ans_skb)
 986                 kfree_skb(ans_skb);
 987         rcu_read_unlock();
 988         return err;
 989 }
 990
 991 /*
 992  * Fill flow entry for nl flow query.  Called with rcu_lock
 993  *
 994  */
 995 static
 996 int
 997 dp_fill_flow(struct ofp_flow_mod* ofm, struct swt_iterator* iter)
 998 {
 999         ofm->header.version  = OFP_VERSION;
1000         ofm->header.type     = OFPT_FLOW_MOD;
1001         ofm->header.length   = htons(sizeof(struct ofp_flow_mod)
1002                                 + sizeof(ofm->actions[0]));
1003         ofm->header.xid      = htonl(0);
1004
1005         ofm->match.wildcards = htons(iter->flow->key.wildcards);
1006         ofm->match.in_port   = iter->flow->key.in_port;
1007         ofm->match.dl_vlan   = iter->flow->key.dl_vlan;
1008         memcpy(ofm->match.dl_src, iter->flow->key.dl_src, ETH_ALEN);
1009         memcpy(ofm->match.dl_dst, iter->flow->key.dl_dst, ETH_ALEN);
1010         ofm->match.dl_type   = iter->flow->key.dl_type;
1011         ofm->match.nw_src    = iter->flow->key.nw_src;
1012         ofm->match.nw_dst    = iter->flow->key.nw_dst;
1013         ofm->match.nw_proto  = iter->flow->key.nw_proto;
1014         ofm->match.tp_src    = iter->flow->key.tp_src;
1015         ofm->match.tp_dst    = iter->flow->key.tp_dst;
1016         ofm->group_id        = iter->flow->group_id;
1017         ofm->max_idle        = iter->flow->max_idle;
1018         /* TODO support multiple actions  */
1019         ofm->actions[0]      = iter->flow->actions[0];
1020
1021         return 0;
1022 }
1023
1024 static int dp_genl_show(struct sk_buff *skb, struct genl_info *info)
1025 {
1026         struct datapath *dp;
1027         int err = -ENOMEM;
1028         struct sk_buff *ans_skb = NULL;
1029         void *data;
1030         struct nlattr *attr;
1031         struct ofp_data_hello *odh;
1032         size_t odh_max_len, odh_len, port_max_len, len;
1033         int port_count;
1034
1035         if (!info->attrs[DP_GENL_A_DP_IDX])
1036                 return -EINVAL;
1037
1038         mutex_lock(&dp_mutex);
1039         dp = dp_get(nla_get_u32((info->attrs[DP_GENL_A_DP_IDX])));
1040         if (!dp)
1041                 goto error;
1042
1043         /* Overallocate, since we can't reliably determine the number of
1044          * ports a priori. */
1045         port_max_len = sizeof(struct ofp_phy_port) * OFPP_MAX;
1046
1047         len = nla_total_size(sizeof(*odh) + port_max_len)
1048                         + nla_total_size(sizeof(uint32_t));
1049
1050         ans_skb = nlmsg_new(len, GFP_KERNEL);
1051         if (!ans_skb)
1052                 goto error;
1053
1054         data = genlmsg_put_reply(ans_skb, info, &dp_genl_family,
1055                                  0, DP_GENL_C_SHOW_DP);
1056         if (data == NULL)
1057                 goto error;
1058
1059         NLA_PUT_U32(ans_skb, DP_GENL_A_DP_IDX, dp->dp_idx);
1060
1061         odh_max_len = sizeof(*odh) + port_max_len;
1062         attr = nla_reserve(ans_skb, DP_GENL_A_DP_INFO, odh_max_len);
1063         if (!attr)
1064                 goto error;
1065         odh = nla_data(attr);
1066         port_count = fill_data_hello(dp, odh);
1067
1068         /* Only now that we know how many ports we've added can we say
1069          * say something about the length. */
1070         odh_len = sizeof(*odh) + (sizeof(struct ofp_phy_port) * port_count);
1071         odh->header.length = htons(odh_len);
1072
1073         /* Take back the unused part that was reserved */
1074         nla_unreserve(ans_skb, attr, (odh_max_len - odh_len));
1075
1076         genlmsg_end(ans_skb, data);
1077         err = genlmsg_reply(ans_skb, info);
1078         if (!err)
1079                 ans_skb = NULL;
1080
1081 error:
1082 nla_put_failure:
1083         if (ans_skb)
1084                 kfree_skb(ans_skb);
1085         mutex_unlock(&dp_mutex);
1086         return err;
1087 }
1088
1089 static struct genl_ops dp_genl_ops_show_dp = {
1090         .cmd = DP_GENL_C_SHOW_DP,
1091         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1092         .policy = dp_genl_policy,
1093         .doit = dp_genl_show,
1094         .dumpit = NULL,
1095 };
1096
1097 /* Convenience function */
1098 static
1099 void*
1100 dp_init_nl_flow_msg(uint32_t dp_idx, uint16_t table_idx,
1101                 struct genl_info *info, struct sk_buff* skb)
1102 {
1103         void* data;
1104
1105         data = genlmsg_put_reply(skb, info, &dp_genl_family, 0,
1106                                 DP_GENL_C_QUERY_FLOW);
1107         if (data == NULL)
1108                 return NULL;
1109         NLA_PUT_U32(skb, DP_GENL_A_DP_IDX,   dp_idx);
1110         NLA_PUT_U16(skb, DP_GENL_A_TABLEIDX, table_idx);
1111
1112         return data;
1113
1114 nla_put_failure:
1115         return NULL;
1116 }
1117
1118 /*  Iterate through the specified table and send all flow entries over
1119  *  netlink to userspace.  Each flow message has the following format:
1120  *
1121  *  32bit dpix
1122  *  16bit tabletype
1123  *  32bit number of flows
1124  *  openflow-flow-entries
1125  *
1126  *  The full table may require multiple messages.  A message with 0 flows
1127  *  signifies end-of message.
1128  */
1129
1130 static
1131 int
1132 dp_dump_table(struct datapath *dp, uint16_t table_idx, struct genl_info *info, struct ofp_flow_mod* matchme)
1133 {
1134         struct sk_buff  *skb = 0;
1135         struct sw_table *table = 0;
1136         struct swt_iterator iter;
1137         struct sw_flow_key in_flow;
1138         struct nlattr   *attr;
1139         int count = 0, sum_count = 0;
1140         void *data;
1141         uint8_t* ofm_ptr = 0;
1142         struct nlattr   *num_attr;
1143         int err = -ENOMEM;
1144
1145         table = dp->chain->tables[table_idx];
1146         if ( table == NULL ) {
1147                 dprintk("dp::dp_dump_table error, non-existant table at position %d\n", table_idx);
1148                 return -EINVAL;
1149         }
1150
1151         if (!table->iterator(table, &iter)) {
1152                 dprintk("dp::dp_dump_table couldn't initialize empty table iterator\n");
1153                 return -ENOMEM;
1154         }
1155
1156         while (iter.flow) {
1157
1158                 /* verify that we can fit all NL_FLOWS_PER_MESSAGE in a single
1159                  * sk_buf */
1160                 if( (sizeof(dp_genl_family) + sizeof(uint32_t) + sizeof(uint16_t) + sizeof(uint32_t) +
1161                                         (NL_FLOWS_PER_MESSAGE * sizeof(struct ofp_flow_mod))) > (8192 - 64)){
1162                         dprintk("dp::dp_dump_table NL_FLOWS_PER_MESSAGE may cause overrun in skbuf\n");
1163                         return -ENOMEM;
1164                 }
1165
1166                 skb = nlmsg_new(8192 - 64, GFP_ATOMIC);
1167                 if (skb == NULL) {
1168                         return -ENOMEM;
1169                 }
1170
1171                 data = dp_init_nl_flow_msg(dp->dp_idx, table_idx, info, skb);
1172                 if (data == NULL){
1173                         err= -ENOMEM;
1174                         goto error_free_skb;
1175                 }
1176
1177                 /* reserve space to put the number of flows for this message, to
1178                  * be filled after the loop*/
1179                 num_attr = nla_reserve(skb, DP_GENL_A_NUMFLOWS, sizeof(uint32_t));
1180                 if(!num_attr){
1181                         err = -ENOMEM;
1182                         goto error_free_skb;
1183                 }
1184
1185                 /* Only load NL_FLOWS_PER_MESSAGE flows at a time */
1186                 attr = nla_reserve(skb, DP_GENL_A_FLOW,
1187                                 (sizeof(struct ofp_flow_mod) + sizeof(struct ofp_action)) * NL_FLOWS_PER_MESSAGE);
1188                 if (!attr){
1189                         err = -ENOMEM;
1190                         goto error_free_skb;
1191                 }
1192
1193                 /* internal loop to fill NL_FLOWS_PER_MESSAGE flows */
1194                 ofm_ptr = nla_data(attr);
1195                 flow_extract_match(&in_flow, &matchme->match);
1196                 while (iter.flow && count < NL_FLOWS_PER_MESSAGE) {
1197                         if(flow_matches(&in_flow, &iter.flow->key)){
1198                                 if((err = dp_fill_flow((struct ofp_flow_mod*)ofm_ptr, &iter)))
1199                                         goto error_free_skb;
1200                                 count++;
1201                                 /* TODO support multiple actions  */
1202                                 ofm_ptr += sizeof(struct ofp_flow_mod) + sizeof(struct ofp_action);
1203                         }
1204                         table->iterator_next(&iter);
1205                 }
1206
1207                 *((uint32_t*)nla_data(num_attr)) = count;
1208                 genlmsg_end(skb, data);
1209
1210                 sum_count += count;
1211                 count = 0;
1212
1213                 err = genlmsg_unicast(skb, info->snd_pid);
1214                 skb = 0;
1215         }
1216
1217         /* send a sentinal message saying we're done */
1218         skb = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
1219         if (skb == NULL) {
1220                 return -ENOMEM;
1221         }
1222         data = dp_init_nl_flow_msg(dp->dp_idx, table_idx, info, skb);
1223         if (data == NULL){
1224                 err= -ENOMEM;
1225                 goto error_free_skb;
1226         }
1227
1228         NLA_PUT_U32(skb, DP_GENL_A_NUMFLOWS,   0);
1229         /* dummy flow so nl doesn't complain */
1230         attr = nla_reserve(skb, DP_GENL_A_FLOW, sizeof(struct ofp_flow_mod));
1231         if (!attr){
1232                 err = -ENOMEM;
1233                 goto error_free_skb;
1234         }
1235         genlmsg_end(skb, data);
1236         err = genlmsg_reply(skb, info); skb = 0;
1237
1238 nla_put_failure:
1239 error_free_skb:
1240         if(skb)
1241                 kfree_skb(skb);
1242         return err;
1243 }
1244
1245 /* Helper function to query_table which creates and sends a message packed with
1246  * table stats.  Message form is:
1247  *
1248  * u32 DP_IDX
1249  * u32 NUM_TABLES
1250  * OFP_TABLE (list of OFP_TABLES)
1251  *
1252  */
1253
1254 static
1255 int
1256 dp_dump_table_stats(struct datapath *dp, int dp_idx, struct genl_info *info)
1257 {
1258         struct sk_buff   *skb = 0;
1259         struct ofp_table *ot = 0;
1260         struct nlattr   *attr;
1261         struct sw_table_stats stats;
1262         void *data;
1263         int err = -ENOMEM;
1264         int i = 0;
1265         int nt = dp->chain->n_tables;
1266
1267         /* u32 IDX, u32 NUMTABLES, list-of-tables */
1268         skb = nlmsg_new(4 + 4 + (sizeof(struct ofp_table) * nt), GFP_ATOMIC);
1269         if (skb == NULL) {
1270                 return -ENOMEM;
1271         }
1272
1273         data = genlmsg_put_reply(skb, info, &dp_genl_family, 0,
1274                                 DP_GENL_C_QUERY_TABLE);
1275         if (data == NULL){
1276                 return -ENOMEM;
1277         }
1278
1279         NLA_PUT_U32(skb, DP_GENL_A_DP_IDX,      dp_idx);
1280         NLA_PUT_U32(skb, DP_GENL_A_NUMTABLES, nt);
1281
1282         /* ... we assume that all tables can fit in a single message.
1283          * Probably a reasonable assumption seeing that we only have
1284          * 3 atm */
1285         attr = nla_reserve(skb, DP_GENL_A_TABLE, (sizeof(struct ofp_table) * nt));
1286         if (!attr){
1287                 err = -ENOMEM;
1288                 goto error_free_skb;
1289         }
1290
1291         ot = nla_data(attr);
1292
1293         for (i = 0; i < nt; ++i) {
1294                 dp->chain->tables[i]->stats(dp->chain->tables[i], &stats);
1295                 ot->header.version = OFP_VERSION;
1296                 ot->header.type    = OFPT_TABLE;
1297                 ot->header.length  = htons(sizeof(struct ofp_table));
1298                 ot->header.xid     = htonl(0);
1299
1300                 strncpy(ot->name, stats.name, OFP_MAX_TABLE_NAME_LEN);
1301                 ot->table_id  = htons(i);
1302                 ot->n_flows   = htonl(stats.n_flows);
1303                 ot->max_flows = htonl(stats.max_flows);
1304                 ot++;
1305         }
1306
1307
1308         genlmsg_end(skb, data);
1309         err = genlmsg_reply(skb, info); skb = 0;
1310
1311 nla_put_failure:
1312 error_free_skb:
1313         if(skb)
1314                 kfree_skb(skb);
1315         return err;
1316 }
1317
1318 /*
1319  * Queries a datapath for flow-table statistics
1320  */
1321
1322
1323 static int dp_genl_table_query(struct sk_buff *skb, struct genl_info *info)
1324 {
1325         struct   datapath* dp;
1326         int       err = 0;
1327
1328         if (!info->attrs[DP_GENL_A_DP_IDX]) {
1329                 dprintk("dp::dp_genl_table_query received message with missing attributes\n");
1330                 return -EINVAL;
1331         }
1332
1333         rcu_read_lock();
1334         dp = dp_get(nla_get_u32(info->attrs[DP_GENL_A_DP_IDX]));
1335         if (!dp) {
1336                 err = -ENOENT;
1337                 goto err_out;
1338         }
1339
1340         err = dp_dump_table_stats(dp, nla_get_u32(info->attrs[DP_GENL_A_DP_IDX]), info);
1341
1342 err_out:
1343         rcu_read_unlock();
1344         return err;
1345 }
1346
1347 /*
1348  * Queries a datapath for flow-table entries.
1349  */
1350
1351 static int dp_genl_flow_query(struct sk_buff *skb, struct genl_info *info)
1352 {
1353         struct datapath* dp;
1354         struct ofp_flow_mod*  ofm;
1355         u16     table_idx;
1356         int     err = 0;
1357
1358         if (!info->attrs[DP_GENL_A_DP_IDX]
1359                                 || !info->attrs[DP_GENL_A_TABLEIDX]
1360                                 || !info->attrs[DP_GENL_A_FLOW]) {
1361                 dprintk("dp::dp_genl_flow_query received message with missing attributes\n");
1362                 return -EINVAL;
1363         }
1364
1365         rcu_read_lock();
1366         dp = dp_get(nla_get_u32(info->attrs[DP_GENL_A_DP_IDX]));
1367         if (!dp) {
1368                 err = -ENOENT;
1369                 goto err_out;
1370         }
1371
1372         table_idx = nla_get_u16(info->attrs[DP_GENL_A_TABLEIDX]);
1373
1374         if (dp->chain->n_tables <= table_idx){
1375                 printk("table index %d invalid (dp has %d tables)\n",
1376                                 table_idx, dp->chain->n_tables);
1377         err = -EINVAL;
1378                 goto err_out;
1379         }
1380
1381         ofm = nla_data(info->attrs[DP_GENL_A_FLOW]);
1382         err = dp_dump_table(dp, table_idx, info, ofm);
1383
1384 err_out:
1385         rcu_read_unlock();
1386         return err;
1387 }
1388
1389 static struct nla_policy dp_genl_flow_policy[DP_GENL_A_MAX + 1] = {
1390         [DP_GENL_A_DP_IDX]      = { .type = NLA_U32 },
1391         [DP_GENL_A_TABLEIDX] = { .type = NLA_U16 },
1392         [DP_GENL_A_NUMFLOWS]  = { .type = NLA_U32 },
1393 };
1394
1395 static struct genl_ops dp_genl_ops_query_flow = {
1396         .cmd    = DP_GENL_C_QUERY_FLOW,
1397         .flags  = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1398         .policy = dp_genl_flow_policy,
1399         .doit   = dp_genl_flow_query,
1400         .dumpit = NULL,
1401 };
1402
1403 static struct nla_policy dp_genl_table_policy[DP_GENL_A_MAX + 1] = {
1404         [DP_GENL_A_DP_IDX]      = { .type = NLA_U32 },
1405 };
1406
1407 static struct genl_ops dp_genl_ops_query_table = {
1408         .cmd    = DP_GENL_C_QUERY_TABLE,
1409         .flags  = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1410         .policy = dp_genl_table_policy,
1411         .doit   = dp_genl_table_query,
1412         .dumpit = NULL,
1413 };
1414
1415
1416 static struct genl_ops dp_genl_ops_query_dp = {
1417         .cmd = DP_GENL_C_QUERY_DP,
1418         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1419         .policy = dp_genl_policy,
1420         .doit = dp_genl_query,
1421         .dumpit = NULL,
1422 };
1423
1424 static int dp_genl_add_del_port(struct sk_buff *skb, struct genl_info *info)
1425 {
1426         struct datapath *dp;
1427         struct net_device *port;
1428         int err;
1429
1430         if (!info->attrs[DP_GENL_A_DP_IDX] || !info->attrs[DP_GENL_A_PORTNAME])
1431                 return -EINVAL;
1432
1433         /* Get datapath. */
1434         mutex_lock(&dp_mutex);
1435         dp = dp_get(nla_get_u32(info->attrs[DP_GENL_A_DP_IDX]));
1436         if (!dp) {
1437                 err = -ENOENT;
1438                 goto out;
1439         }
1440
1441         /* Get interface to add/remove. */
1442         port = dev_get_by_name(&init_net,
1443                         nla_data(info->attrs[DP_GENL_A_PORTNAME]));
1444         if (!port) {
1445                 err = -ENOENT;
1446                 goto out;
1447         }
1448
1449         /* Execute operation. */
1450         if (info->genlhdr->cmd == DP_GENL_C_ADD_PORT)
1451                 err = add_switch_port(dp, port);
1452         else {
1453                 if (port->br_port == NULL || port->br_port->dp != dp) {
1454                         err = -ENOENT;
1455                         goto out_put;
1456                 }
1457                 err = del_switch_port(port->br_port);
1458         }
1459
1460 out_put:
1461         dev_put(port);
1462 out:
1463         mutex_unlock(&dp_mutex);
1464         return err;
1465 }
1466
1467 static struct genl_ops dp_genl_ops_add_port = {
1468         .cmd = DP_GENL_C_ADD_PORT,
1469         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1470         .policy = dp_genl_policy,
1471         .doit = dp_genl_add_del_port,
1472         .dumpit = NULL,
1473 };
1474
1475 static struct genl_ops dp_genl_ops_del_port = {
1476         .cmd = DP_GENL_C_DEL_PORT,
1477         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1478         .policy = dp_genl_policy,
1479         .doit = dp_genl_add_del_port,
1480         .dumpit = NULL,
1481 };
1482
1483 static int dp_genl_openflow(struct sk_buff *skb, struct genl_info *info)
1484 {
1485         struct nlattr *va = info->attrs[DP_GENL_A_OPENFLOW];
1486         struct datapath *dp;
1487         int err;
1488
1489         if (!info->attrs[DP_GENL_A_DP_IDX] || !va)
1490                 return -EINVAL;
1491
1492         rcu_read_lock();
1493         dp = dp_get(nla_get_u32(info->attrs[DP_GENL_A_DP_IDX]));
1494         if (!dp) {
1495                 err = -ENOENT;
1496                 goto out;
1497         }
1498
1499         va = info->attrs[DP_GENL_A_OPENFLOW];
1500
1501         err = fwd_control_input(dp->chain, nla_data(va), nla_len(va));
1502
1503 out:
1504         rcu_read_unlock();
1505         return err;
1506 }
1507
1508 static struct nla_policy dp_genl_openflow_policy[DP_GENL_A_MAX + 1] = {
1509         [DP_GENL_A_DP_IDX] = { .type = NLA_U32 },
1510 };
1511
1512 static struct genl_ops dp_genl_ops_openflow = {
1513         .cmd = DP_GENL_C_OPENFLOW,
1514         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1515         .policy = dp_genl_openflow_policy,
1516         .doit = dp_genl_openflow,
1517         .dumpit = NULL,
1518 };
1519
1520 static struct nla_policy dp_genl_benchmark_policy[DP_GENL_A_MAX + 1] = {
1521         [DP_GENL_A_DP_IDX] = { .type = NLA_U32 },
1522         [DP_GENL_A_NPACKETS] = { .type = NLA_U32 },
1523         [DP_GENL_A_PSIZE] = { .type = NLA_U32 },
1524 };
1525
1526 static struct genl_ops dp_genl_ops_benchmark_nl = {
1527         .cmd = DP_GENL_C_BENCHMARK_NL,
1528         .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1529         .policy = dp_genl_benchmark_policy,
1530         .doit = dp_genl_benchmark_nl,
1531         .dumpit = NULL,
1532 };
1533
1534 static struct genl_ops *dp_genl_all_ops[] = {
1535         /* Keep this operation first.  Generic Netlink dispatching
1536          * looks up operations with linear search, so we want it at the
1537          * front. */
1538         &dp_genl_ops_openflow,
1539
1540         &dp_genl_ops_query_flow,
1541         &dp_genl_ops_query_table,
1542         &dp_genl_ops_show_dp,
1543         &dp_genl_ops_add_dp,
1544         &dp_genl_ops_del_dp,
1545         &dp_genl_ops_query_dp,
1546         &dp_genl_ops_add_port,
1547         &dp_genl_ops_del_port,
1548         &dp_genl_ops_benchmark_nl,
1549 };
1550
1551 static int dp_init_netlink(void)
1552 {
1553         int err;
1554         int i;
1555
1556         err = genl_register_family(&dp_genl_family);
1557         if (err)
1558                 return err;
1559
1560         for (i = 0; i < ARRAY_SIZE(dp_genl_all_ops); i++) {
1561                 err = genl_register_ops(&dp_genl_family, dp_genl_all_ops[i]);
1562                 if (err)
1563                         goto err_unregister;
1564         }
1565
1566         strcpy(mc_group.name, "openflow");
1567         err = genl_register_mc_group(&dp_genl_family, &mc_group);
1568         if (err < 0)
1569                 goto err_unregister;
1570
1571         return 0;
1572
1573 err_unregister:
1574         genl_unregister_family(&dp_genl_family);
1575                 return err;
1576 }
1577
1578 static void dp_uninit_netlink(void)
1579 {
1580         genl_unregister_family(&dp_genl_family);
1581 }
1582
1583 #define DRV_NAME                "openflow"
1584 #define DRV_VERSION      VERSION
1585 #define DRV_DESCRIPTION "OpenFlow switching datapath implementation"
1586 #define DRV_COPYRIGHT   "Copyright (c) 2007, 2008 The Board of Trustees of The Leland Stanford Junior University"
1587
1588
1589 static int __init dp_init(void)
1590 {
1591         int err;
1592
1593         printk(KERN_INFO DRV_NAME ": " DRV_DESCRIPTION "\n");
1594         printk(KERN_INFO DRV_NAME ": " VERSION" built on "__DATE__" "__TIME__"\n");
1595         printk(KERN_INFO DRV_NAME ": " DRV_COPYRIGHT "\n");
1596
1597         err = flow_init();
1598         if (err)
1599                 goto error;
1600
1601         err = dp_init_netlink();
1602         if (err)
1603                 goto error_flow_exit;
1604
1605         /* Hook into callback used by the bridge to intercept packets.
1606          * Parasites we are. */
1607         if (br_handle_frame_hook)
1608                 printk("openflow: hijacking bridge hook\n");
1609         br_handle_frame_hook = dp_frame_hook;
1610
1611         return 0;
1612
1613 error_flow_exit:
1614         flow_exit();
1615 error:
1616         printk(KERN_EMERG "openflow: failed to install!");
1617         return err;
1618 }
1619
1620 static void dp_cleanup(void)
1621 {
1622         fwd_exit();
1623         dp_uninit_netlink();
1624         flow_exit();
1625         br_handle_frame_hook = NULL;
1626 }
1627
1628 module_init(dp_init);
1629 module_exit(dp_cleanup);
1630
1631 MODULE_DESCRIPTION(DRV_DESCRIPTION);
1632 MODULE_AUTHOR(DRV_COPYRIGHT);
1633 MODULE_LICENSE("GPL");