summaryrefslogtreecommitdiff
path: root/drivers/net/ipvlan/ipvlan_l3s.c
blob: d17480a911a33d461403c405c442c1930dee19e1 (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
/* Copyright (c) 2014 Mahesh Bandewar <maheshb@google.com>
 *
 * 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.
 */

#include "ipvlan.h"

static unsigned int ipvlan_netid __read_mostly;

struct ipvlan_netns {
	unsigned int ipvl_nf_hook_refcnt;
};

static struct ipvl_addr *ipvlan_skb_to_addr(struct sk_buff *skb,
					    struct net_device *dev)
{
	struct ipvl_addr *addr = NULL;
	struct ipvl_port *port;
	int addr_type;
	void *lyr3h;

	if (!dev || !netif_is_ipvlan_port(dev))
		goto out;

	port = ipvlan_port_get_rcu(dev);
	if (!port || port->mode != IPVLAN_MODE_L3S)
		goto out;

	lyr3h = ipvlan_get_L3_hdr(port, skb, &addr_type);
	if (!lyr3h)
		goto out;

	addr = ipvlan_addr_lookup(port, lyr3h, addr_type, true);
out:
	return addr;
}

static struct sk_buff *ipvlan_l3_rcv(struct net_device *dev,
				     struct sk_buff *skb, u16 proto)
{
	struct ipvl_addr *addr;
	struct net_device *sdev;

	addr = ipvlan_skb_to_addr(skb, dev);
	if (!addr)
		goto out;

	sdev = addr->master->dev;
	switch (proto) {
	case AF_INET:
	{
		struct iphdr *ip4h = ip_hdr(skb);
		int err;

		err = ip_route_input_noref(skb, ip4h->daddr, ip4h->saddr,
					   ip4h->tos, sdev);
		if (unlikely(err))
			goto out;
		break;
	}
#if IS_ENABLED(CONFIG_IPV6)
	case AF_INET6:
	{
		struct dst_entry *dst;
		struct ipv6hdr *ip6h = ipv6_hdr(skb);
		int flags = RT6_LOOKUP_F_HAS_SADDR;
		struct flowi6 fl6 = {
			.flowi6_iif   = sdev->ifindex,
			.daddr        = ip6h->daddr,
			.saddr        = ip6h->saddr,
			.flowlabel    = ip6_flowinfo(ip6h),
			.flowi6_mark  = skb->mark,
			.flowi6_proto = ip6h->nexthdr,
		};

		skb_dst_drop(skb);
		dst = ip6_route_input_lookup(dev_net(sdev), sdev, &fl6,
					     skb, flags);
		skb_dst_set(skb, dst);
		break;
	}
#endif
	default:
		break;
	}
out:
	return skb;
}

static const struct l3mdev_ops ipvl_l3mdev_ops = {
	.l3mdev_l3_rcv = ipvlan_l3_rcv,
};

static unsigned int ipvlan_nf_input(void *priv, struct sk_buff *skb,
				    const struct nf_hook_state *state)
{
	struct ipvl_addr *addr;
	unsigned int len;

	addr = ipvlan_skb_to_addr(skb, skb->dev);
	if (!addr)
		goto out;

	skb->dev = addr->master->dev;
	len = skb->len + ETH_HLEN;
	ipvlan_count_rx(addr->master, len, true, false);
out:
	return NF_ACCEPT;
}

static const struct nf_hook_ops ipvl_nfops[] = {
	{
		.hook     = ipvlan_nf_input,
		.pf       = NFPROTO_IPV4,
		.hooknum  = NF_INET_LOCAL_IN,
		.priority = INT_MAX,
	},
#if IS_ENABLED(CONFIG_IPV6)
	{
		.hook     = ipvlan_nf_input,
		.pf       = NFPROTO_IPV6,
		.hooknum  = NF_INET_LOCAL_IN,
		.priority = INT_MAX,
	},
#endif
};

static int ipvlan_register_nf_hook(struct net *net)
{
	struct ipvlan_netns *vnet = net_generic(net, ipvlan_netid);
	int err = 0;

	if (!vnet->ipvl_nf_hook_refcnt) {
		err = nf_register_net_hooks(net, ipvl_nfops,
					    ARRAY_SIZE(ipvl_nfops));
		if (!err)
			vnet->ipvl_nf_hook_refcnt = 1;
	} else {
		vnet->ipvl_nf_hook_refcnt++;
	}

	return err;
}

static void ipvlan_unregister_nf_hook(struct net *net)
{
	struct ipvlan_netns *vnet = net_generic(net, ipvlan_netid);

	if (WARN_ON(!vnet->ipvl_nf_hook_refcnt))
		return;

	vnet->ipvl_nf_hook_refcnt--;
	if (!vnet->ipvl_nf_hook_refcnt)
		nf_unregister_net_hooks(net, ipvl_nfops,
					ARRAY_SIZE(ipvl_nfops));
}

void ipvlan_migrate_l3s_hook(struct net *oldnet, struct net *newnet)
{
	struct ipvlan_netns *old_vnet;

	ASSERT_RTNL();

	old_vnet = net_generic(oldnet, ipvlan_netid);
	if (!old_vnet->ipvl_nf_hook_refcnt)
		return;

	ipvlan_register_nf_hook(newnet);
	ipvlan_unregister_nf_hook(oldnet);
}

static void ipvlan_ns_exit(struct net *net)
{
	struct ipvlan_netns *vnet = net_generic(net, ipvlan_netid);

	if (WARN_ON_ONCE(vnet->ipvl_nf_hook_refcnt)) {
		vnet->ipvl_nf_hook_refcnt = 0;
		nf_unregister_net_hooks(net, ipvl_nfops,
					ARRAY_SIZE(ipvl_nfops));
	}
}

static struct pernet_operations ipvlan_net_ops = {
	.id   = &ipvlan_netid,
	.size = sizeof(struct ipvlan_netns),
	.exit = ipvlan_ns_exit,
};

int ipvlan_l3s_init(void)
{
	return register_pernet_subsys(&ipvlan_net_ops);
}

void ipvlan_l3s_cleanup(void)
{
	unregister_pernet_subsys(&ipvlan_net_ops);
}

int ipvlan_l3s_register(struct ipvl_port *port)
{
	struct net_device *dev = port->dev;
	int ret;

	ASSERT_RTNL();

	ret = ipvlan_register_nf_hook(read_pnet(&port->pnet));
	if (!ret) {
		dev->l3mdev_ops = &ipvl_l3mdev_ops;
		dev->priv_flags |= IFF_L3MDEV_RX_HANDLER;
	}

	return ret;
}

void ipvlan_l3s_unregister(struct ipvl_port *port)
{
	struct net_device *dev = port->dev;

	ASSERT_RTNL();

	dev->priv_flags &= ~IFF_L3MDEV_RX_HANDLER;
	ipvlan_unregister_nf_hook(read_pnet(&port->pnet));
	dev->l3mdev_ops = NULL;
}