summaryrefslogtreecommitdiff
path: root/drivers/net/geneve.c
blob: b7eafa4c1a673efa2672c1ae13ff599b6d389818 (plain)
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
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
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
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
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
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
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
338
339
340
341
342
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
390
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
417
418
419
420
421
422
423
424
425
426
427
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
465
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
/*
 * GENEVE: Generic Network Virtualization Encapsulation
 *
 * Copyright (c) 2015 Red Hat, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/hash.h>
#include <net/rtnetlink.h>
#include <net/geneve.h>

#define GENEVE_NETDEV_VER	"0.6"

#define GENEVE_UDP_PORT		6081

#define GENEVE_N_VID		(1u << 24)
#define GENEVE_VID_MASK		(GENEVE_N_VID - 1)

#define VNI_HASH_BITS		10
#define VNI_HASH_SIZE		(1<<VNI_HASH_BITS)

static bool log_ecn_error = true;
module_param(log_ecn_error, bool, 0644);
MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");

/* per-network namespace private data for this module */
struct geneve_net {
	struct list_head  geneve_list;
	struct hlist_head vni_list[VNI_HASH_SIZE];
};

/* Pseudo network device */
struct geneve_dev {
	struct hlist_node  hlist;	/* vni hash table */
	struct net	   *net;	/* netns for packet i/o */
	struct net_device  *dev;	/* netdev for geneve tunnel */
	struct geneve_sock *sock;	/* socket used for geneve tunnel */
	u8 vni[3];			/* virtual network ID for tunnel */
	struct sockaddr_in remote;	/* IPv4 address for link partner */
	struct list_head   next;	/* geneve's per namespace list */
};

static int geneve_net_id;

static inline __u32 geneve_net_vni_hash(u8 vni[3])
{
	__u32 vnid;

	vnid = (vni[0] << 16) | (vni[1] << 8) | vni[2];
	return hash_32(vnid, VNI_HASH_BITS);
}

/* geneve receive/decap routine */
static void geneve_rx(struct geneve_sock *gs, struct sk_buff *skb)
{
	struct genevehdr *gnvh = geneve_hdr(skb);
	struct geneve_dev *dummy, *geneve = NULL;
	struct geneve_net *gn;
	struct iphdr *iph = NULL;
	struct pcpu_sw_netstats *stats;
	struct hlist_head *vni_list_head;
	int err = 0;
	__u32 hash;

	iph = ip_hdr(skb); /* Still outer IP header... */

	gn = gs->rcv_data;

	/* Find the device for this VNI */
	hash = geneve_net_vni_hash(gnvh->vni);
	vni_list_head = &gn->vni_list[hash];
	hlist_for_each_entry_rcu(dummy, vni_list_head, hlist) {
		if (!memcmp(gnvh->vni, dummy->vni, sizeof(dummy->vni)) &&
		    iph->saddr == dummy->remote.sin_addr.s_addr) {
			geneve = dummy;
			break;
		}
	}
	if (!geneve)
		goto drop;

	/* Drop packets w/ critical options,
	 * since we don't support any...
	 */
	if (gnvh->critical)
		goto drop;

	skb_reset_mac_header(skb);
	skb_scrub_packet(skb, !net_eq(geneve->net, dev_net(geneve->dev)));
	skb->protocol = eth_type_trans(skb, geneve->dev);
	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);

	/* Ignore packet loops (and multicast echo) */
	if (ether_addr_equal(eth_hdr(skb)->h_source, geneve->dev->dev_addr))
		goto drop;

	skb_reset_network_header(skb);

	iph = ip_hdr(skb); /* Now inner IP header... */
	err = IP_ECN_decapsulate(iph, skb);

	if (unlikely(err)) {
		if (log_ecn_error)
			net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
					     &iph->saddr, iph->tos);
		if (err > 1) {
			++geneve->dev->stats.rx_frame_errors;
			++geneve->dev->stats.rx_errors;
			goto drop;
		}
	}

	stats = this_cpu_ptr(geneve->dev->tstats);
	u64_stats_update_begin(&stats->syncp);
	stats->rx_packets++;
	stats->rx_bytes += skb->len;
	u64_stats_update_end(&stats->syncp);

	netif_rx(skb);

	return;
drop:
	/* Consume bad packet */
	kfree_skb(skb);
}

/* Setup stats when device is created */
static int geneve_init(struct net_device *dev)
{
	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
	if (!dev->tstats)
		return -ENOMEM;

	return 0;
}

static void geneve_uninit(struct net_device *dev)
{
	free_percpu(dev->tstats);
}

static int geneve_open(struct net_device *dev)
{
	struct geneve_dev *geneve = netdev_priv(dev);
	struct net *net = geneve->net;
	struct geneve_net *gn = net_generic(geneve->net, geneve_net_id);
	struct geneve_sock *gs;

	gs = geneve_sock_add(net, htons(GENEVE_UDP_PORT), geneve_rx, gn,
	                     false, false);
	if (IS_ERR(gs))
		return PTR_ERR(gs);

	geneve->sock = gs;

	return 0;
}

static int geneve_stop(struct net_device *dev)
{
	struct geneve_dev *geneve = netdev_priv(dev);
	struct geneve_sock *gs = geneve->sock;

	geneve_sock_release(gs);

	return 0;
}

static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct geneve_dev *geneve = netdev_priv(dev);
	struct geneve_sock *gs = geneve->sock;
	struct rtable *rt = NULL;
	const struct iphdr *iip; /* interior IP header */
	struct flowi4 fl4;
	int err;
	__be16 sport;
	__u8 tos, ttl = 0;

	iip = ip_hdr(skb);

	skb_reset_mac_header(skb);

	/* TODO: port min/max limits should be configurable */
	sport = udp_flow_src_port(dev_net(dev), skb, 0, 0, true);

	memset(&fl4, 0, sizeof(fl4));
	fl4.daddr = geneve->remote.sin_addr.s_addr;
	rt = ip_route_output_key(geneve->net, &fl4);
	if (IS_ERR(rt)) {
		netdev_dbg(dev, "no route to %pI4\n", &fl4.daddr);
		dev->stats.tx_carrier_errors++;
		goto tx_error;
	}
	if (rt->dst.dev == dev) { /* is this necessary? */
		netdev_dbg(dev, "circular route to %pI4\n", &fl4.daddr);
		dev->stats.collisions++;
		goto rt_tx_error;
	}

	/* TODO: tos and ttl should be configurable */

	tos = ip_tunnel_ecn_encap(0, iip, skb);

	if (IN_MULTICAST(ntohl(fl4.daddr)))
		ttl = 1;

	ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);

	/* no need to handle local destination and encap bypass...yet... */

	err = geneve_xmit_skb(gs, rt, skb, fl4.saddr, fl4.daddr,
	                      tos, ttl, 0, sport, htons(GENEVE_UDP_PORT), 0,
	                      geneve->vni, 0, NULL, false,
	                      !net_eq(geneve->net, dev_net(geneve->dev)));
	if (err < 0)
		ip_rt_put(rt);

	iptunnel_xmit_stats(err, &dev->stats, dev->tstats);

	return NETDEV_TX_OK;

rt_tx_error:
	ip_rt_put(rt);
tx_error:
	dev->stats.tx_errors++;
	dev_kfree_skb(skb);
	return NETDEV_TX_OK;
}

static const struct net_device_ops geneve_netdev_ops = {
	.ndo_init		= geneve_init,
	.ndo_uninit		= geneve_uninit,
	.ndo_open		= geneve_open,
	.ndo_stop		= geneve_stop,
	.ndo_start_xmit		= geneve_xmit,
	.ndo_get_stats64	= ip_tunnel_get_stats64,
	.ndo_change_mtu		= eth_change_mtu,
	.ndo_validate_addr	= eth_validate_addr,
	.ndo_set_mac_address	= eth_mac_addr,
};

static void geneve_get_drvinfo(struct net_device *dev,
			       struct ethtool_drvinfo *drvinfo)
{
	strlcpy(drvinfo->version, GENEVE_NETDEV_VER, sizeof(drvinfo->version));
	strlcpy(drvinfo->driver, "geneve", sizeof(drvinfo->driver));
}

static const struct ethtool_ops geneve_ethtool_ops = {
	.get_drvinfo	= geneve_get_drvinfo,
	.get_link	= ethtool_op_get_link,
};

/* Info for udev, that this is a virtual tunnel endpoint */
static struct device_type geneve_type = {
	.name = "geneve",
};

/* Initialize the device structure. */
static void geneve_setup(struct net_device *dev)
{
	ether_setup(dev);

	dev->netdev_ops = &geneve_netdev_ops;
	dev->ethtool_ops = &geneve_ethtool_ops;
	dev->destructor = free_netdev;

	SET_NETDEV_DEVTYPE(dev, &geneve_type);

	dev->tx_queue_len = 0;
	dev->features    |= NETIF_F_LLTX;
	dev->features    |= NETIF_F_SG | NETIF_F_HW_CSUM;
	dev->features    |= NETIF_F_RXCSUM;
	dev->features    |= NETIF_F_GSO_SOFTWARE;

	dev->vlan_features = dev->features;
	dev->features    |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;

	dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
	dev->hw_features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;

	netif_keep_dst(dev);
	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
}

static const struct nla_policy geneve_policy[IFLA_GENEVE_MAX + 1] = {
	[IFLA_GENEVE_ID]		= { .type = NLA_U32 },
	[IFLA_GENEVE_REMOTE]		= { .len = FIELD_SIZEOF(struct iphdr, daddr) },
};

static int geneve_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;
	}

	if (!data)
		return -EINVAL;

	if (data[IFLA_GENEVE_ID]) {
		__u32 vni =  nla_get_u32(data[IFLA_GENEVE_ID]);

		if (vni >= GENEVE_VID_MASK)
			return -ERANGE;
	}

	return 0;
}

static int geneve_newlink(struct net *net, struct net_device *dev,
			 struct nlattr *tb[], struct nlattr *data[])
{
	struct geneve_net *gn = net_generic(net, geneve_net_id);
	struct geneve_dev *dummy, *geneve = netdev_priv(dev);
	struct hlist_head *vni_list_head;
	struct sockaddr_in remote;	/* IPv4 address for link partner */
	__u32 vni, hash;
	int err;

	if (!data[IFLA_GENEVE_ID] || !data[IFLA_GENEVE_REMOTE])
		return -EINVAL;

	geneve->net = net;
	geneve->dev = dev;

	vni = nla_get_u32(data[IFLA_GENEVE_ID]);
	geneve->vni[0] = (vni & 0x00ff0000) >> 16;
	geneve->vni[1] = (vni & 0x0000ff00) >> 8;
	geneve->vni[2] =  vni & 0x000000ff;

	geneve->remote.sin_addr.s_addr =
		nla_get_in_addr(data[IFLA_GENEVE_REMOTE]);
	if (IN_MULTICAST(ntohl(geneve->remote.sin_addr.s_addr)))
		return -EINVAL;

	remote = geneve->remote;
	hash = geneve_net_vni_hash(geneve->vni);
	vni_list_head = &gn->vni_list[hash];
	hlist_for_each_entry_rcu(dummy, vni_list_head, hlist) {
		if (!memcmp(geneve->vni, dummy->vni, sizeof(dummy->vni)) &&
		    !memcmp(&remote, &dummy->remote, sizeof(dummy->remote)))
			return -EBUSY;
	}

	if (tb[IFLA_ADDRESS] == NULL)
		eth_hw_addr_random(dev);

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

	list_add(&geneve->next, &gn->geneve_list);

	hlist_add_head_rcu(&geneve->hlist, &gn->vni_list[hash]);

	return 0;
}

static void geneve_dellink(struct net_device *dev, struct list_head *head)
{
	struct geneve_dev *geneve = netdev_priv(dev);

	if (!hlist_unhashed(&geneve->hlist))
		hlist_del_rcu(&geneve->hlist);

	list_del(&geneve->next);
	unregister_netdevice_queue(dev, head);
}

static size_t geneve_get_size(const struct net_device *dev)
{
	return nla_total_size(sizeof(__u32)) +	/* IFLA_GENEVE_ID */
		nla_total_size(sizeof(struct in_addr)) + /* IFLA_GENEVE_REMOTE */
		0;
}

static int geneve_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
	struct geneve_dev *geneve = netdev_priv(dev);
	__u32 vni;

	vni = (geneve->vni[0] << 16) | (geneve->vni[1] << 8) | geneve->vni[2];
	if (nla_put_u32(skb, IFLA_GENEVE_ID, vni))
		goto nla_put_failure;

	if (nla_put_in_addr(skb, IFLA_GENEVE_REMOTE,
			    geneve->remote.sin_addr.s_addr))
		goto nla_put_failure;

	return 0;

nla_put_failure:
	return -EMSGSIZE;
}

static struct rtnl_link_ops geneve_link_ops __read_mostly = {
	.kind		= "geneve",
	.maxtype	= IFLA_GENEVE_MAX,
	.policy		= geneve_policy,
	.priv_size	= sizeof(struct geneve_dev),
	.setup		= geneve_setup,
	.validate	= geneve_validate,
	.newlink	= geneve_newlink,
	.dellink	= geneve_dellink,
	.get_size	= geneve_get_size,
	.fill_info	= geneve_fill_info,
};

static __net_init int geneve_init_net(struct net *net)
{
	struct geneve_net *gn = net_generic(net, geneve_net_id);
	unsigned int h;

	INIT_LIST_HEAD(&gn->geneve_list);

	for (h = 0; h < VNI_HASH_SIZE; ++h)
		INIT_HLIST_HEAD(&gn->vni_list[h]);

	return 0;
}

static void __net_exit geneve_exit_net(struct net *net)
{
	struct geneve_net *gn = net_generic(net, geneve_net_id);
	struct geneve_dev *geneve, *next;
	struct net_device *dev, *aux;
	LIST_HEAD(list);

	rtnl_lock();

	/* gather any geneve devices that were moved into this ns */
	for_each_netdev_safe(net, dev, aux)
		if (dev->rtnl_link_ops == &geneve_link_ops)
			unregister_netdevice_queue(dev, &list);

	/* now gather any other geneve devices that were created in this ns */
	list_for_each_entry_safe(geneve, next, &gn->geneve_list, next) {
		/* If geneve->dev is in the same netns, it was already added
		 * to the list by the previous loop.
		 */
		if (!net_eq(dev_net(geneve->dev), net))
			unregister_netdevice_queue(geneve->dev, &list);
	}

	/* unregister the devices gathered above */
	unregister_netdevice_many(&list);
	rtnl_unlock();
}

static struct pernet_operations geneve_net_ops = {
	.init = geneve_init_net,
	.exit = geneve_exit_net,
	.id   = &geneve_net_id,
	.size = sizeof(struct geneve_net),
};

static int __init geneve_init_module(void)
{
	int rc;

	rc = register_pernet_subsys(&geneve_net_ops);
	if (rc)
		goto out1;

	rc = rtnl_link_register(&geneve_link_ops);
	if (rc)
		goto out2;

	return 0;
out2:
	unregister_pernet_subsys(&geneve_net_ops);
out1:
	return rc;
}
late_initcall(geneve_init_module);

static void __exit geneve_cleanup_module(void)
{
	rtnl_link_unregister(&geneve_link_ops);
	unregister_pernet_subsys(&geneve_net_ops);
}
module_exit(geneve_cleanup_module);

MODULE_LICENSE("GPL");
MODULE_VERSION(GENEVE_NETDEV_VER);
MODULE_AUTHOR("John W. Linville <linville@tuxdriver.com>");
MODULE_DESCRIPTION("Interface driver for GENEVE encapsulated traffic");
MODULE_ALIAS_RTNL_LINK("geneve");