summaryrefslogtreecommitdiffstats
path: root/net/8021q/vlan_core.c
blob: 544f9cb9678c417aef5aea1b7f7399c952908e0a (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
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if_vlan.h>
#include <linux/netpoll.h>
#include <linux/export.h>
#include "vlan.h"

bool vlan_do_receive(struct sk_buff **skbp, bool last_handler)
{
	struct sk_buff *skb = *skbp;
	u16 vlan_id = skb->vlan_tci & VLAN_VID_MASK;
	struct net_device *vlan_dev;
	struct vlan_pcpu_stats *rx_stats;

	vlan_dev = vlan_find_dev(skb->dev, vlan_id);
	if (!vlan_dev) {
		/* Only the last call to vlan_do_receive() should change
		 * pkt_type to PACKET_OTHERHOST
		 */
		if (vlan_id && last_handler)
			skb->pkt_type = PACKET_OTHERHOST;
		return false;
	}

	skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
	if (unlikely(!skb))
		return false;

	skb->dev = vlan_dev;
	if (skb->pkt_type == PACKET_OTHERHOST) {
		/* Our lower layer thinks this is not local, let's make sure.
		 * This allows the VLAN to have a different MAC than the
		 * underlying device, and still route correctly. */
		if (!compare_ether_addr(eth_hdr(skb)->h_dest,
					vlan_dev->dev_addr))
			skb->pkt_type = PACKET_HOST;
	}

	if (!(vlan_dev_priv(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR)) {
		unsigned int offset = skb->data - skb_mac_header(skb);

		/*
		 * vlan_insert_tag expect skb->data pointing to mac header.
		 * So change skb->data before calling it and change back to
		 * original position later
		 */
		skb_push(skb, offset);
		skb = *skbp = vlan_insert_tag(skb, skb->vlan_tci);
		if (!skb)
			return false;
		skb_pull(skb, offset + VLAN_HLEN);
		skb_reset_mac_len(skb);
	}

	skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
	skb->vlan_tci = 0;

	rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);

	u64_stats_update_begin(&rx_stats->syncp);
	rx_stats->rx_packets++;
	rx_stats->rx_bytes += skb->len;
	if (skb->pkt_type == PACKET_MULTICAST)
		rx_stats->rx_multicast++;
	u64_stats_update_end(&rx_stats->syncp);

	return true;
}

/* Must be invoked with rcu_read_lock or with RTNL. */
struct net_device *__vlan_find_dev_deep(struct net_device *real_dev,
					u16 vlan_id)
{
	struct vlan_group *grp = rcu_dereference_rtnl(real_dev->vlgrp);

	if (grp) {
		return vlan_group_get_device(grp, vlan_id);
	} else {
		/*
		 * Bonding slaves do not have grp assigned to themselves.
		 * Grp is assigned to bonding master instead.
		 */
		if (netif_is_bond_slave(real_dev))
			return __vlan_find_dev_deep(real_dev->master, vlan_id);
	}

	return NULL;
}
EXPORT_SYMBOL(__vlan_find_dev_deep);

struct net_device *vlan_dev_real_dev(const struct net_device *dev)
{
	return vlan_dev_priv(dev)->real_dev;
}
EXPORT_SYMBOL(vlan_dev_real_dev);

u16 vlan_dev_vlan_id(const struct net_device *dev)
{
	return vlan_dev_priv(dev)->vlan_id;
}
EXPORT_SYMBOL(vlan_dev_vlan_id);

static struct sk_buff *vlan_reorder_header(struct sk_buff *skb)
{
	if (skb_cow(skb, skb_headroom(skb)) < 0)
		return NULL;
	memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 2 * ETH_ALEN);
	skb->mac_header += VLAN_HLEN;
	skb_reset_mac_len(skb);
	return skb;
}

struct sk_buff *vlan_untag(struct sk_buff *skb)
{
	struct vlan_hdr *vhdr;
	u16 vlan_tci;

	if (unlikely(vlan_tx_tag_present(skb))) {
		/* vlan_tci is already set-up so leave this for another time */
		return skb;
	}

	skb = skb_share_check(skb, GFP_ATOMIC);
	if (unlikely(!skb))
		goto err_free;

	if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
		goto err_free;

	vhdr = (struct vlan_hdr *) skb->data;
	vlan_tci = ntohs(vhdr->h_vlan_TCI);
	__vlan_hwaccel_put_tag(skb, vlan_tci);

	skb_pull_rcsum(skb, VLAN_HLEN);
	vlan_set_encap_proto(skb, vhdr);

	skb = vlan_reorder_header(skb);
	if (unlikely(!skb))
		goto err_free;

	skb_reset_network_header(skb);
	skb_reset_transport_header(skb);
	return skb;

err_free:
	kfree_skb(skb);
	return NULL;
}

int vlan_vid_add(struct net_device *dev, unsigned short vid)
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if ((dev->features & NETIF_F_HW_VLAN_FILTER) &&
	     ops->ndo_vlan_rx_add_vid) {
		return ops->ndo_vlan_rx_add_vid(dev, vid);
	}
	return 0;
}
EXPORT_SYMBOL(vlan_vid_add);

void vlan_vid_del(struct net_device *dev, unsigned short vid)
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if ((dev->features & NETIF_F_HW_VLAN_FILTER) &&
	     ops->ndo_vlan_rx_kill_vid) {
		ops->ndo_vlan_rx_kill_vid(dev, vid);
	}
}
EXPORT_SYMBOL(vlan_vid_del);