macvlan.c 13.2 KB
Newer Older
Patrick McHardy's avatar
Patrick McHardy committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164
/*
 * Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * The code this is based on carried the following copyright notice:
 * ---
 * (C) Copyright 2001-2006
 * Alex Zeffertt, Cambridge Broadband Ltd, ajz@cambridgebroadband.com
 * Re-worked by Ben Greear <greearb@candelatech.com>
 * ---
 */
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/list.h>
#include <linux/notifier.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/if_arp.h>
#include <linux/if_link.h>
#include <linux/if_macvlan.h>
#include <net/rtnetlink.h>

#define MACVLAN_HASH_SIZE	(1 << BITS_PER_BYTE)

struct macvlan_port {
	struct net_device	*dev;
	struct hlist_head	vlan_hash[MACVLAN_HASH_SIZE];
	struct list_head	vlans;
};

struct macvlan_dev {
	struct net_device	*dev;
	struct list_head	list;
	struct hlist_node	hlist;
	struct macvlan_port	*port;
	struct net_device	*lowerdev;
};


static struct macvlan_dev *macvlan_hash_lookup(const struct macvlan_port *port,
					       const unsigned char *addr)
{
	struct macvlan_dev *vlan;
	struct hlist_node *n;

	hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[addr[5]], hlist) {
		if (!compare_ether_addr(vlan->dev->dev_addr, addr))
			return vlan;
	}
	return NULL;
}

static void macvlan_broadcast(struct sk_buff *skb,
			      const struct macvlan_port *port)
{
	const struct ethhdr *eth = eth_hdr(skb);
	const struct macvlan_dev *vlan;
	struct hlist_node *n;
	struct net_device *dev;
	struct sk_buff *nskb;
	unsigned int i;

	for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
		hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
			dev = vlan->dev;

			nskb = skb_clone(skb, GFP_ATOMIC);
			if (nskb == NULL) {
				dev->stats.rx_errors++;
				dev->stats.rx_dropped++;
				continue;
			}

			dev->stats.rx_bytes += skb->len + ETH_HLEN;
			dev->stats.rx_packets++;
			dev->stats.multicast++;
			dev->last_rx = jiffies;

			nskb->dev = dev;
			if (!compare_ether_addr(eth->h_dest, dev->broadcast))
				nskb->pkt_type = PACKET_BROADCAST;
			else
				nskb->pkt_type = PACKET_MULTICAST;

			netif_rx(nskb);
		}
	}
}

/* called under rcu_read_lock() from netif_receive_skb */
static struct sk_buff *macvlan_handle_frame(struct sk_buff *skb)
{
	const struct ethhdr *eth = eth_hdr(skb);
	const struct macvlan_port *port;
	const struct macvlan_dev *vlan;
	struct net_device *dev;

	port = rcu_dereference(skb->dev->macvlan_port);
	if (port == NULL)
		return skb;

	if (is_multicast_ether_addr(eth->h_dest)) {
		macvlan_broadcast(skb, port);
		return skb;
	}

	vlan = macvlan_hash_lookup(port, eth->h_dest);
	if (vlan == NULL)
		return skb;

	dev = vlan->dev;
	if (unlikely(!(dev->flags & IFF_UP))) {
		kfree_skb(skb);
		return NULL;
	}

	skb = skb_share_check(skb, GFP_ATOMIC);
	if (skb == NULL) {
		dev->stats.rx_errors++;
		dev->stats.rx_dropped++;
		return NULL;
	}

	dev->stats.rx_bytes += skb->len + ETH_HLEN;
	dev->stats.rx_packets++;
	dev->last_rx = jiffies;

	skb->dev = dev;
	skb->pkt_type = PACKET_HOST;

	netif_rx(skb);
	return NULL;
}

static int macvlan_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	unsigned int len = skb->len;
	int ret;

	skb->dev = vlan->lowerdev;
	ret = dev_queue_xmit(skb);

	if (likely(ret == NET_XMIT_SUCCESS)) {
		dev->stats.tx_packets++;
		dev->stats.tx_bytes += len;
	} else {
		dev->stats.tx_errors++;
		dev->stats.tx_aborted_errors++;
	}
	return NETDEV_TX_OK;
}

static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
165 166
			       unsigned short type, const void *daddr,
			       const void *saddr, unsigned len)
Patrick McHardy's avatar
Patrick McHardy committed
167 168 169 170
{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

171 172
	return dev_hard_header(skb, lowerdev, type, daddr,
			       saddr ? : dev->dev_addr, len);
Patrick McHardy's avatar
Patrick McHardy committed
173 174
}

175 176 177 178 179 180 181 182
static const struct header_ops macvlan_hard_header_ops = {
	.create  	= macvlan_hard_header,
	.rebuild	= eth_rebuild_header,
	.parse		= eth_header_parse,
	.cache		= eth_header_cache,
	.cache_update	= eth_header_cache_update,
};

Patrick McHardy's avatar
Patrick McHardy committed
183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215
static int macvlan_open(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct macvlan_port *port = vlan->port;
	struct net_device *lowerdev = vlan->lowerdev;
	int err;

	err = dev_unicast_add(lowerdev, dev->dev_addr, ETH_ALEN);
	if (err < 0)
		return err;
	if (dev->flags & IFF_ALLMULTI)
		dev_set_allmulti(lowerdev, 1);

	hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[dev->dev_addr[5]]);
	return 0;
}

static int macvlan_stop(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

	dev_mc_unsync(lowerdev, dev);
	if (dev->flags & IFF_ALLMULTI)
		dev_set_allmulti(lowerdev, -1);

	dev_unicast_delete(lowerdev, dev->dev_addr, ETH_ALEN);

	hlist_del_rcu(&vlan->hlist);
	synchronize_rcu();
	return 0;
}

216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238
static int macvlan_set_mac_address(struct net_device *dev, void *p)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;
	struct sockaddr *addr = p;
	int err;

	if (!is_valid_ether_addr(addr->sa_data))
		return -EADDRNOTAVAIL;

	if (!(dev->flags & IFF_UP))
		goto out;

	err = dev_unicast_add(lowerdev, addr->sa_data, ETH_ALEN);
	if (err < 0)
		return err;
	dev_unicast_delete(lowerdev, dev->dev_addr, ETH_ALEN);

out:
	memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
	return 0;
}

Patrick McHardy's avatar
Patrick McHardy committed
239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279
static void macvlan_change_rx_flags(struct net_device *dev, int change)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

	if (change & IFF_ALLMULTI)
		dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
}

static void macvlan_set_multicast_list(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);

	dev_mc_sync(vlan->lowerdev, dev);
}

static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
{
	struct macvlan_dev *vlan = netdev_priv(dev);

	if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
		return -EINVAL;
	dev->mtu = new_mtu;
	return 0;
}

/*
 * macvlan network devices have devices nesting below it and are a special
 * "super class" of normal network devices; split their locks off into a
 * separate class since they always nest.
 */
static struct lock_class_key macvlan_netdev_xmit_lock_key;

#define MACVLAN_FEATURES \
	(NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
	 NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
	 NETIF_F_TSO_ECN | NETIF_F_TSO6)

#define MACVLAN_STATE_MASK \
	((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))

280 281 282 283 284 285 286 287 288 289 290
static void macvlan_set_lockdep_class_one(struct netdev_queue *txq)
{
	lockdep_set_class(&txq->_xmit_lock,
			  &macvlan_netdev_xmit_lock_key);
}

static void macvlan_set_lockdep_class(struct net_device *dev)
{
	macvlan_set_lockdep_class_one(&dev->tx_queue);
}

Patrick McHardy's avatar
Patrick McHardy committed
291 292 293 294 295 296 297 298 299 300
static int macvlan_init(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	const struct net_device *lowerdev = vlan->lowerdev;

	dev->state		= (dev->state & ~MACVLAN_STATE_MASK) |
				  (lowerdev->state & MACVLAN_STATE_MASK);
	dev->features 		= lowerdev->features & MACVLAN_FEATURES;
	dev->iflink		= lowerdev->ifindex;

301 302
	macvlan_set_lockdep_class(dev);

Patrick McHardy's avatar
Patrick McHardy committed
303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337
	return 0;
}

static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
					struct ethtool_drvinfo *drvinfo)
{
	snprintf(drvinfo->driver, 32, "macvlan");
	snprintf(drvinfo->version, 32, "0.1");
}

static u32 macvlan_ethtool_get_rx_csum(struct net_device *dev)
{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

	if (lowerdev->ethtool_ops->get_rx_csum == NULL)
		return 0;
	return lowerdev->ethtool_ops->get_rx_csum(lowerdev);
}

static const struct ethtool_ops macvlan_ethtool_ops = {
	.get_link		= ethtool_op_get_link,
	.get_rx_csum		= macvlan_ethtool_get_rx_csum,
	.get_drvinfo		= macvlan_ethtool_get_drvinfo,
};

static void macvlan_setup(struct net_device *dev)
{
	ether_setup(dev);

	dev->init		= macvlan_init;
	dev->open		= macvlan_open;
	dev->stop		= macvlan_stop;
	dev->change_mtu		= macvlan_change_mtu;
	dev->change_rx_flags	= macvlan_change_rx_flags;
338
	dev->set_mac_address	= macvlan_set_mac_address;
Patrick McHardy's avatar
Patrick McHardy committed
339 340 341
	dev->set_multicast_list	= macvlan_set_multicast_list;
	dev->hard_start_xmit	= macvlan_hard_start_xmit;
	dev->destructor		= free_netdev;
342
	dev->header_ops		= &macvlan_hard_header_ops,
Patrick McHardy's avatar
Patrick McHardy committed
343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389
	dev->ethtool_ops	= &macvlan_ethtool_ops;
	dev->tx_queue_len	= 0;
}

static int macvlan_port_create(struct net_device *dev)
{
	struct macvlan_port *port;
	unsigned int i;

	if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
		return -EINVAL;

	port = kzalloc(sizeof(*port), GFP_KERNEL);
	if (port == NULL)
		return -ENOMEM;

	port->dev = dev;
	INIT_LIST_HEAD(&port->vlans);
	for (i = 0; i < MACVLAN_HASH_SIZE; i++)
		INIT_HLIST_HEAD(&port->vlan_hash[i]);
	rcu_assign_pointer(dev->macvlan_port, port);
	return 0;
}

static void macvlan_port_destroy(struct net_device *dev)
{
	struct macvlan_port *port = dev->macvlan_port;

	rcu_assign_pointer(dev->macvlan_port, NULL);
	synchronize_rcu();
	kfree(port);
}

static void macvlan_transfer_operstate(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	const struct net_device *lowerdev = vlan->lowerdev;

	if (lowerdev->operstate == IF_OPER_DORMANT)
		netif_dormant_on(dev);
	else
		netif_dormant_off(dev);

	if (netif_carrier_ok(lowerdev)) {
		if (!netif_carrier_ok(dev))
			netif_carrier_on(dev);
	} else {
390
		if (netif_carrier_ok(dev))
Patrick McHardy's avatar
Patrick McHardy committed
391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416
			netif_carrier_off(dev);
	}
}

static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
{
	if (tb[IFLA_ADDRESS]) {
		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
			return -EINVAL;
		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
			return -EADDRNOTAVAIL;
	}
	return 0;
}

static int macvlan_newlink(struct net_device *dev,
			   struct nlattr *tb[], struct nlattr *data[])
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct macvlan_port *port;
	struct net_device *lowerdev;
	int err;

	if (!tb[IFLA_LINK])
		return -EINVAL;

417
	lowerdev = __dev_get_by_index(dev_net(dev), nla_get_u32(tb[IFLA_LINK]));
Patrick McHardy's avatar
Patrick McHardy committed
418 419 420
	if (lowerdev == NULL)
		return -ENODEV;

421 422 423 424 425 426 427
	/* Don't allow macvlans on top of other macvlans - its not really
	 * wrong, but lockdep can't handle it and its not useful for anything
	 * you couldn't do directly on top of the real device.
	 */
	if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops)
		return -ENODEV;

Patrick McHardy's avatar
Patrick McHardy committed
428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464
	if (!tb[IFLA_MTU])
		dev->mtu = lowerdev->mtu;
	else if (dev->mtu > lowerdev->mtu)
		return -EINVAL;

	if (!tb[IFLA_ADDRESS])
		random_ether_addr(dev->dev_addr);

	if (lowerdev->macvlan_port == NULL) {
		err = macvlan_port_create(lowerdev);
		if (err < 0)
			return err;
	}
	port = lowerdev->macvlan_port;

	vlan->lowerdev = lowerdev;
	vlan->dev      = dev;
	vlan->port     = port;

	err = register_netdevice(dev);
	if (err < 0)
		return err;

	list_add_tail(&vlan->list, &port->vlans);
	macvlan_transfer_operstate(dev);
	return 0;
}

static void macvlan_dellink(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct macvlan_port *port = vlan->port;

	list_del(&vlan->list);
	unregister_netdevice(dev);

	if (list_empty(&port->vlans))
465
		macvlan_port_destroy(port->dev);
Patrick McHardy's avatar
Patrick McHardy committed
466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522
}

static struct rtnl_link_ops macvlan_link_ops __read_mostly = {
	.kind		= "macvlan",
	.priv_size	= sizeof(struct macvlan_dev),
	.setup		= macvlan_setup,
	.validate	= macvlan_validate,
	.newlink	= macvlan_newlink,
	.dellink	= macvlan_dellink,
};

static int macvlan_device_event(struct notifier_block *unused,
				unsigned long event, void *ptr)
{
	struct net_device *dev = ptr;
	struct macvlan_dev *vlan, *next;
	struct macvlan_port *port;

	port = dev->macvlan_port;
	if (port == NULL)
		return NOTIFY_DONE;

	switch (event) {
	case NETDEV_CHANGE:
		list_for_each_entry(vlan, &port->vlans, list)
			macvlan_transfer_operstate(vlan->dev);
		break;
	case NETDEV_FEAT_CHANGE:
		list_for_each_entry(vlan, &port->vlans, list) {
			vlan->dev->features = dev->features & MACVLAN_FEATURES;
			netdev_features_change(vlan->dev);
		}
		break;
	case NETDEV_UNREGISTER:
		list_for_each_entry_safe(vlan, next, &port->vlans, list)
			macvlan_dellink(vlan->dev);
		break;
	}
	return NOTIFY_DONE;
}

static struct notifier_block macvlan_notifier_block __read_mostly = {
	.notifier_call	= macvlan_device_event,
};

static int __init macvlan_init_module(void)
{
	int err;

	register_netdevice_notifier(&macvlan_notifier_block);
	macvlan_handle_frame_hook = macvlan_handle_frame;

	err = rtnl_link_register(&macvlan_link_ops);
	if (err < 0)
		goto err1;
	return 0;
err1:
523
	macvlan_handle_frame_hook = NULL;
Patrick McHardy's avatar
Patrick McHardy committed
524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541
	unregister_netdevice_notifier(&macvlan_notifier_block);
	return err;
}

static void __exit macvlan_cleanup_module(void)
{
	rtnl_link_unregister(&macvlan_link_ops);
	macvlan_handle_frame_hook = NULL;
	unregister_netdevice_notifier(&macvlan_notifier_block);
}

module_init(macvlan_init_module);
module_exit(macvlan_cleanup_module);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_DESCRIPTION("Driver for MAC address based VLANs");
MODULE_ALIAS_RTNL_LINK("macvlan");