1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright 2011-2014 Autronica Fire and Security AS
3 *
4 * Author(s):
5 * 2011-2014 Arvid Brodin, arvid.brodin@alten.se
6 */
7
8 #include "hsr_slave.h"
9 #include <linux/etherdevice.h>
10 #include <linux/if_arp.h>
11 #include <linux/if_vlan.h>
12 #include "hsr_main.h"
13 #include "hsr_device.h"
14 #include "hsr_forward.h"
15 #include "hsr_framereg.h"
16
hsr_handle_frame(struct sk_buff ** pskb)17 static rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
18 {
19 struct sk_buff *skb = *pskb;
20 struct hsr_port *port;
21 u16 protocol;
22
23 if (!skb_mac_header_was_set(skb)) {
24 WARN_ONCE(1, "%s: skb invalid", __func__);
25 return RX_HANDLER_PASS;
26 }
27
28 rcu_read_lock(); /* hsr->node_db, hsr->ports */
29 port = hsr_port_get_rcu(skb->dev);
30
31 if (hsr_addr_is_self(port->hsr, eth_hdr(skb)->h_source)) {
32 /* Directly kill frames sent by ourselves */
33 kfree_skb(skb);
34 goto finish_consume;
35 }
36
37 protocol = eth_hdr(skb)->h_proto;
38 if (protocol != htons(ETH_P_PRP) && protocol != htons(ETH_P_HSR))
39 goto finish_pass;
40
41 skb_push(skb, ETH_HLEN);
42
43 hsr_forward_skb(skb, port);
44
45 finish_consume:
46 rcu_read_unlock(); /* hsr->node_db, hsr->ports */
47 return RX_HANDLER_CONSUMED;
48
49 finish_pass:
50 rcu_read_unlock(); /* hsr->node_db, hsr->ports */
51 return RX_HANDLER_PASS;
52 }
53
hsr_port_exists(const struct net_device * dev)54 bool hsr_port_exists(const struct net_device *dev)
55 {
56 return rcu_access_pointer(dev->rx_handler) == hsr_handle_frame;
57 }
58
hsr_check_dev_ok(struct net_device * dev)59 static int hsr_check_dev_ok(struct net_device *dev)
60 {
61 /* Don't allow HSR on non-ethernet like devices */
62 if ((dev->flags & IFF_LOOPBACK) || dev->type != ARPHRD_ETHER ||
63 dev->addr_len != ETH_ALEN) {
64 netdev_info(dev, "Cannot use loopback or non-ethernet device as HSR slave.\n");
65 return -EINVAL;
66 }
67
68 /* Don't allow enslaving hsr devices */
69 if (is_hsr_master(dev)) {
70 netdev_info(dev, "Cannot create trees of HSR devices.\n");
71 return -EINVAL;
72 }
73
74 if (hsr_port_exists(dev)) {
75 netdev_info(dev, "This device is already a HSR slave.\n");
76 return -EINVAL;
77 }
78
79 if (is_vlan_dev(dev)) {
80 netdev_info(dev, "HSR on top of VLAN is not yet supported in this driver.\n");
81 return -EINVAL;
82 }
83
84 if (dev->priv_flags & IFF_DONT_BRIDGE) {
85 netdev_info(dev, "This device does not support bridging.\n");
86 return -EOPNOTSUPP;
87 }
88
89 /* HSR over bonded devices has not been tested, but I'm not sure it
90 * won't work...
91 */
92
93 return 0;
94 }
95
96 /* Setup device to be added to the HSR bridge. */
hsr_portdev_setup(struct net_device * dev,struct hsr_port * port)97 static int hsr_portdev_setup(struct net_device *dev, struct hsr_port *port)
98 {
99 int res;
100
101 dev_hold(dev);
102 res = dev_set_promiscuity(dev, 1);
103 if (res)
104 goto fail_promiscuity;
105
106 /* FIXME:
107 * What does net device "adjacency" mean? Should we do
108 * res = netdev_master_upper_dev_link(port->dev, port->hsr->dev); ?
109 */
110
111 res = netdev_rx_handler_register(dev, hsr_handle_frame, port);
112 if (res)
113 goto fail_rx_handler;
114 dev_disable_lro(dev);
115
116 return 0;
117
118 fail_rx_handler:
119 dev_set_promiscuity(dev, -1);
120 fail_promiscuity:
121 dev_put(dev);
122
123 return res;
124 }
125
hsr_add_port(struct hsr_priv * hsr,struct net_device * dev,enum hsr_port_type type)126 int hsr_add_port(struct hsr_priv *hsr, struct net_device *dev,
127 enum hsr_port_type type)
128 {
129 struct hsr_port *port, *master;
130 int res;
131
132 if (type != HSR_PT_MASTER) {
133 res = hsr_check_dev_ok(dev);
134 if (res)
135 return res;
136 }
137
138 port = hsr_port_get_hsr(hsr, type);
139 if (port)
140 return -EBUSY; /* This port already exists */
141
142 port = kzalloc(sizeof(*port), GFP_KERNEL);
143 if (!port)
144 return -ENOMEM;
145
146 if (type != HSR_PT_MASTER) {
147 res = hsr_portdev_setup(dev, port);
148 if (res)
149 goto fail_dev_setup;
150 }
151
152 port->hsr = hsr;
153 port->dev = dev;
154 port->type = type;
155
156 list_add_tail_rcu(&port->port_list, &hsr->ports);
157 synchronize_rcu();
158
159 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
160 netdev_update_features(master->dev);
161 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr));
162
163 return 0;
164
165 fail_dev_setup:
166 kfree(port);
167 return res;
168 }
169
hsr_del_port(struct hsr_port * port)170 void hsr_del_port(struct hsr_port *port)
171 {
172 struct hsr_priv *hsr;
173 struct hsr_port *master;
174
175 hsr = port->hsr;
176 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
177 list_del_rcu(&port->port_list);
178
179 if (port != master) {
180 if (master) {
181 netdev_update_features(master->dev);
182 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr));
183 }
184 netdev_rx_handler_unregister(port->dev);
185 dev_set_promiscuity(port->dev, -1);
186 }
187
188 /* FIXME?
189 * netdev_upper_dev_unlink(port->dev, port->hsr->dev);
190 */
191
192 synchronize_rcu();
193
194 if (port != master)
195 dev_put(port->dev);
196 kfree(port);
197 }
198