1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2007-2012 Nicira, Inc.
4  */
5 
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7 
8 #include <linux/if_arp.h>
9 #include <linux/if_bridge.h>
10 #include <linux/if_vlan.h>
11 #include <linux/kernel.h>
12 #include <linux/llc.h>
13 #include <linux/rtnetlink.h>
14 #include <linux/skbuff.h>
15 #include <linux/openvswitch.h>
16 #include <linux/export.h>
17 
18 #include <net/ip_tunnels.h>
19 #include <net/rtnetlink.h>
20 
21 #include "datapath.h"
22 #include "vport.h"
23 #include "vport-internal_dev.h"
24 #include "vport-netdev.h"
25 
26 static struct vport_ops ovs_netdev_vport_ops;
27 
28 /* Must be called with rcu_read_lock. */
29 static void netdev_port_receive(struct sk_buff *skb)
30 {
31 	struct vport *vport;
32 
33 	vport = ovs_netdev_get_vport(skb->dev);
34 	if (unlikely(!vport))
35 		goto error;
36 
37 	if (unlikely(skb_warn_if_lro(skb)))
38 		goto error;
39 
40 	/* Make our own copy of the packet.  Otherwise we will mangle the
41 	 * packet for anyone who came before us (e.g. tcpdump via AF_PACKET).
42 	 */
43 	skb = skb_share_check(skb, GFP_ATOMIC);
44 	if (unlikely(!skb))
45 		return;
46 
47 	if (skb->dev->type == ARPHRD_ETHER)
48 		skb_push_rcsum(skb, ETH_HLEN);
49 
50 	ovs_vport_receive(vport, skb, skb_tunnel_info(skb));
51 	return;
52 error:
53 	kfree_skb(skb);
54 }
55 
56 /* Called with rcu_read_lock and bottom-halves disabled. */
57 static rx_handler_result_t netdev_frame_hook(struct sk_buff **pskb)
58 {
59 	struct sk_buff *skb = *pskb;
60 
61 	if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
62 		return RX_HANDLER_PASS;
63 
64 	netdev_port_receive(skb);
65 	return RX_HANDLER_CONSUMED;
66 }
67 
68 static struct net_device *get_dpdev(const struct datapath *dp)
69 {
70 	struct vport *local;
71 
72 	local = ovs_vport_ovsl(dp, OVSP_LOCAL);
73 	return local->dev;
74 }
75 
76 struct vport *ovs_netdev_link(struct vport *vport, const char *name)
77 {
78 	int err;
79 
80 	vport->dev = dev_get_by_name(ovs_dp_get_net(vport->dp), name);
81 	if (!vport->dev) {
82 		err = -ENODEV;
83 		goto error_free_vport;
84 	}
85 	netdev_tracker_alloc(vport->dev, &vport->dev_tracker, GFP_KERNEL);
86 	if (vport->dev->flags & IFF_LOOPBACK ||
87 	    (vport->dev->type != ARPHRD_ETHER &&
88 	     vport->dev->type != ARPHRD_NONE) ||
89 	    ovs_is_internal_dev(vport->dev)) {
90 		err = -EINVAL;
91 		goto error_put;
92 	}
93 
94 	rtnl_lock();
95 	err = netdev_master_upper_dev_link(vport->dev,
96 					   get_dpdev(vport->dp),
97 					   NULL, NULL, NULL);
98 	if (err)
99 		goto error_unlock;
100 
101 	err = netdev_rx_handler_register(vport->dev, netdev_frame_hook,
102 					 vport);
103 	if (err)
104 		goto error_master_upper_dev_unlink;
105 
106 	dev_disable_lro(vport->dev);
107 	dev_set_promiscuity(vport->dev, 1);
108 	vport->dev->priv_flags |= IFF_OVS_DATAPATH;
109 	rtnl_unlock();
110 
111 	return vport;
112 
113 error_master_upper_dev_unlink:
114 	netdev_upper_dev_unlink(vport->dev, get_dpdev(vport->dp));
115 error_unlock:
116 	rtnl_unlock();
117 error_put:
118 	netdev_put(vport->dev, &vport->dev_tracker);
119 error_free_vport:
120 	ovs_vport_free(vport);
121 	return ERR_PTR(err);
122 }
123 EXPORT_SYMBOL_GPL(ovs_netdev_link);
124 
125 static struct vport *netdev_create(const struct vport_parms *parms)
126 {
127 	struct vport *vport;
128 
129 	vport = ovs_vport_alloc(0, &ovs_netdev_vport_ops, parms);
130 	if (IS_ERR(vport))
131 		return vport;
132 
133 	return ovs_netdev_link(vport, parms->name);
134 }
135 
136 static void vport_netdev_free(struct rcu_head *rcu)
137 {
138 	struct vport *vport = container_of(rcu, struct vport, rcu);
139 
140 	netdev_put(vport->dev, &vport->dev_tracker);
141 	ovs_vport_free(vport);
142 }
143 
144 void ovs_netdev_detach_dev(struct vport *vport)
145 {
146 	ASSERT_RTNL();
147 	vport->dev->priv_flags &= ~IFF_OVS_DATAPATH;
148 	netdev_rx_handler_unregister(vport->dev);
149 	netdev_upper_dev_unlink(vport->dev,
150 				netdev_master_upper_dev_get(vport->dev));
151 	dev_set_promiscuity(vport->dev, -1);
152 }
153 
154 static void netdev_destroy(struct vport *vport)
155 {
156 	rtnl_lock();
157 	if (netif_is_ovs_port(vport->dev))
158 		ovs_netdev_detach_dev(vport);
159 	rtnl_unlock();
160 
161 	call_rcu(&vport->rcu, vport_netdev_free);
162 }
163 
164 void ovs_netdev_tunnel_destroy(struct vport *vport)
165 {
166 	rtnl_lock();
167 	if (netif_is_ovs_port(vport->dev))
168 		ovs_netdev_detach_dev(vport);
169 
170 	/* We can be invoked by both explicit vport deletion and
171 	 * underlying netdev deregistration; delete the link only
172 	 * if it's not already shutting down.
173 	 */
174 	if (vport->dev->reg_state == NETREG_REGISTERED)
175 		rtnl_delete_link(vport->dev);
176 	netdev_put(vport->dev, &vport->dev_tracker);
177 	vport->dev = NULL;
178 	rtnl_unlock();
179 
180 	call_rcu(&vport->rcu, vport_netdev_free);
181 }
182 EXPORT_SYMBOL_GPL(ovs_netdev_tunnel_destroy);
183 
184 /* Returns null if this device is not attached to a datapath. */
185 struct vport *ovs_netdev_get_vport(struct net_device *dev)
186 {
187 	if (likely(netif_is_ovs_port(dev)))
188 		return (struct vport *)
189 			rcu_dereference_rtnl(dev->rx_handler_data);
190 	else
191 		return NULL;
192 }
193 
194 static struct vport_ops ovs_netdev_vport_ops = {
195 	.type		= OVS_VPORT_TYPE_NETDEV,
196 	.create		= netdev_create,
197 	.destroy	= netdev_destroy,
198 	.send		= dev_queue_xmit,
199 };
200 
201 int __init ovs_netdev_init(void)
202 {
203 	return ovs_vport_ops_register(&ovs_netdev_vport_ops);
204 }
205 
206 void ovs_netdev_exit(void)
207 {
208 	ovs_vport_ops_unregister(&ovs_netdev_vport_ops);
209 }
210