hsr_slave.c (1cc1eb52734bfd2fc57c7b3337a11198e713580d) hsr_slave.c (f266a683a4804dc499efc6c2206ef68efed029d0)
1/* Copyright 2011-2014 Autronica Fire and Security AS
2 *
3 * This program is free software; you can redistribute it and/or modify it
4 * under the terms of the GNU General Public License as published by the Free
5 * Software Foundation; either version 2 of the License, or (at your option)
6 * any later version.
7 *
8 * Author(s):
9 * 2011-2014 Arvid Brodin, arvid.brodin@alten.se
10 */
11
12#include "hsr_slave.h"
13#include <linux/etherdevice.h>
14#include <linux/if_arp.h>
15#include "hsr_main.h"
16#include "hsr_device.h"
1/* Copyright 2011-2014 Autronica Fire and Security AS
2 *
3 * This program is free software; you can redistribute it and/or modify it
4 * under the terms of the GNU General Public License as published by the Free
5 * Software Foundation; either version 2 of the License, or (at your option)
6 * any later version.
7 *
8 * Author(s):
9 * 2011-2014 Arvid Brodin, arvid.brodin@alten.se
10 */
11
12#include "hsr_slave.h"
13#include <linux/etherdevice.h>
14#include <linux/if_arp.h>
15#include "hsr_main.h"
16#include "hsr_device.h"
17#include "hsr_forward.h"
17#include "hsr_framereg.h"
18
19
18#include "hsr_framereg.h"
19
20
21static rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
22{
23 struct sk_buff *skb = *pskb;
24 struct hsr_port *port;
25
26 if (!skb_mac_header_was_set(skb)) {
27 WARN_ONCE(1, "%s: skb invalid", __func__);
28 return RX_HANDLER_PASS;
29 }
30
31 rcu_read_lock(); /* hsr->node_db, hsr->ports */
32 port = hsr_port_get_rcu(skb->dev);
33
34 if (hsr_addr_is_self(port->hsr, eth_hdr(skb)->h_source)) {
35 /* Directly kill frames sent by ourselves */
36 kfree_skb(skb);
37 goto finish_consume;
38 }
39
40 if (eth_hdr(skb)->h_proto != htons(ETH_P_PRP))
41 goto finish_pass;
42
43 skb_push(skb, ETH_HLEN);
44
45 hsr_forward_skb(skb, port);
46
47finish_consume:
48 rcu_read_unlock(); /* hsr->node_db, hsr->ports */
49 return RX_HANDLER_CONSUMED;
50
51finish_pass:
52 rcu_read_unlock(); /* hsr->node_db, hsr->ports */
53 return RX_HANDLER_PASS;
54}
55
56bool hsr_port_exists(const struct net_device *dev)
57{
58 return rcu_access_pointer(dev->rx_handler) == hsr_handle_frame;
59}
60
61
20static int hsr_check_dev_ok(struct net_device *dev)
21{
22 /* Don't allow HSR on non-ethernet like devices */
23 if ((dev->flags & IFF_LOOPBACK) || (dev->type != ARPHRD_ETHER) ||
24 (dev->addr_len != ETH_ALEN)) {
25 netdev_info(dev, "Cannot use loopback or non-ethernet device as HSR slave.\n");
26 return -EINVAL;
27 }

--- 9 unchanged lines hidden (view full) ---

37 return -EINVAL;
38 }
39
40 if (dev->priv_flags & IFF_802_1Q_VLAN) {
41 netdev_info(dev, "HSR on top of VLAN is not yet supported in this driver.\n");
42 return -EINVAL;
43 }
44
62static int hsr_check_dev_ok(struct net_device *dev)
63{
64 /* Don't allow HSR on non-ethernet like devices */
65 if ((dev->flags & IFF_LOOPBACK) || (dev->type != ARPHRD_ETHER) ||
66 (dev->addr_len != ETH_ALEN)) {
67 netdev_info(dev, "Cannot use loopback or non-ethernet device as HSR slave.\n");
68 return -EINVAL;
69 }

--- 9 unchanged lines hidden (view full) ---

79 return -EINVAL;
80 }
81
82 if (dev->priv_flags & IFF_802_1Q_VLAN) {
83 netdev_info(dev, "HSR on top of VLAN is not yet supported in this driver.\n");
84 return -EINVAL;
85 }
86
87 if (dev->priv_flags & IFF_DONT_BRIDGE) {
88 netdev_info(dev, "This device does not support bridging.\n");
89 return -EOPNOTSUPP;
90 }
91
45 /* HSR over bonded devices has not been tested, but I'm not sure it
46 * won't work...
47 */
48
49 return 0;
50}
51
52
92 /* HSR over bonded devices has not been tested, but I'm not sure it
93 * won't work...
94 */
95
96 return 0;
97}
98
99
53static struct sk_buff *hsr_pull_tag(struct sk_buff *skb)
54{
55 struct hsr_tag *hsr_tag;
56 struct sk_buff *skb2;
57
58 skb2 = skb_share_check(skb, GFP_ATOMIC);
59 if (unlikely(!skb2))
60 goto err_free;
61 skb = skb2;
62
63 if (unlikely(!pskb_may_pull(skb, HSR_HLEN)))
64 goto err_free;
65
66 hsr_tag = (struct hsr_tag *) skb->data;
67 skb->protocol = hsr_tag->encap_proto;
68 skb_pull(skb, HSR_HLEN);
69
70 return skb;
71
72err_free:
73 kfree_skb(skb);
74 return NULL;
75}
76
77
78/* The uses I can see for these HSR supervision frames are:
79 * 1) Use the frames that are sent after node initialization ("HSR_TLV.Type =
80 * 22") to reset any sequence_nr counters belonging to that node. Useful if
81 * the other node's counter has been reset for some reason.
82 * --
83 * Or not - resetting the counter and bridging the frame would create a
84 * loop, unfortunately.
85 *
86 * 2) Use the LifeCheck frames to detect ring breaks. I.e. if no LifeCheck
87 * frame is received from a particular node, we know something is wrong.
88 * We just register these (as with normal frames) and throw them away.
89 *
90 * 3) Allow different MAC addresses for the two slave interfaces, using the
91 * MacAddressA field.
92 */
93static bool is_supervision_frame(struct hsr_priv *hsr, struct sk_buff *skb)
94{
95 struct hsr_sup_tag *hsr_stag;
96
97 if (!ether_addr_equal(eth_hdr(skb)->h_dest,
98 hsr->sup_multicast_addr))
99 return false;
100
101 hsr_stag = (struct hsr_sup_tag *) skb->data;
102 if (get_hsr_stag_path(hsr_stag) != 0x0f)
103 return false;
104 if ((hsr_stag->HSR_TLV_Type != HSR_TLV_ANNOUNCE) &&
105 (hsr_stag->HSR_TLV_Type != HSR_TLV_LIFE_CHECK))
106 return false;
107 if (hsr_stag->HSR_TLV_Length != 12)
108 return false;
109
110 return true;
111}
112
113
114/* Implementation somewhat according to IEC-62439-3, p. 43
115 */
116rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
117{
118 struct sk_buff *skb = *pskb;
119 struct hsr_port *port, *other_port, *master;
120 struct hsr_priv *hsr;
121 struct hsr_node *node;
122 bool deliver_to_self;
123 struct sk_buff *skb_deliver;
124 bool dup_out;
125 int ret;
126
127 if (eth_hdr(skb)->h_proto != htons(ETH_P_PRP))
128 return RX_HANDLER_PASS;
129
130 rcu_read_lock(); /* ports & node */
131
132 port = hsr_port_get_rcu(skb->dev);
133 hsr = port->hsr;
134 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
135
136 node = hsr_find_node(&hsr->self_node_db, skb);
137 if (node) {
138 /* Always kill frames sent by ourselves */
139 kfree_skb(skb);
140 ret = RX_HANDLER_CONSUMED;
141 goto finish;
142 }
143
144 /* Is this frame a candidate for local reception? */
145 deliver_to_self = false;
146 if ((skb->pkt_type == PACKET_HOST) ||
147 (skb->pkt_type == PACKET_MULTICAST) ||
148 (skb->pkt_type == PACKET_BROADCAST))
149 deliver_to_self = true;
150 else if (ether_addr_equal(eth_hdr(skb)->h_dest,
151 master->dev->dev_addr)) {
152 skb->pkt_type = PACKET_HOST;
153 deliver_to_self = true;
154 }
155
156 node = hsr_find_node(&hsr->node_db, skb);
157
158 if (is_supervision_frame(hsr, skb)) {
159 skb_pull(skb, sizeof(struct hsr_sup_tag));
160 node = hsr_merge_node(node, skb, port);
161 if (!node) {
162 kfree_skb(skb);
163 master->dev->stats.rx_dropped++;
164 ret = RX_HANDLER_CONSUMED;
165 goto finish;
166 }
167 skb_push(skb, sizeof(struct hsr_sup_tag));
168 deliver_to_self = false;
169 }
170
171 if (!node) {
172 /* Source node unknown; this might be a HSR frame from
173 * another net (different multicast address). Ignore it.
174 */
175 kfree_skb(skb);
176 ret = RX_HANDLER_CONSUMED;
177 goto finish;
178 }
179
180 if (port->type == HSR_PT_SLAVE_A)
181 other_port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
182 else
183 other_port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
184
185 /* Register ALL incoming frames as outgoing through the other interface.
186 * This allows us to register frames as incoming only if they are valid
187 * for the receiving interface, without using a specific counter for
188 * incoming frames.
189 */
190 if (other_port)
191 dup_out = hsr_register_frame_out(node, other_port, skb);
192 else
193 dup_out = 0;
194 if (!dup_out)
195 hsr_register_frame_in(node, port);
196
197 /* Forward this frame? */
198 if (dup_out || (skb->pkt_type == PACKET_HOST))
199 other_port = NULL;
200
201 if (hsr_register_frame_out(node, master, skb))
202 deliver_to_self = false;
203
204 if (!deliver_to_self && !other_port) {
205 kfree_skb(skb);
206 /* Circulated frame; silently remove it. */
207 ret = RX_HANDLER_CONSUMED;
208 goto finish;
209 }
210
211 skb_deliver = skb;
212 if (deliver_to_self && other_port) {
213 /* skb_clone() is not enough since we will strip the hsr tag
214 * and do address substitution below
215 */
216 skb_deliver = pskb_copy(skb, GFP_ATOMIC);
217 if (!skb_deliver) {
218 deliver_to_self = false;
219 master->dev->stats.rx_dropped++;
220 }
221 }
222
223 if (deliver_to_self) {
224 bool multicast_frame;
225
226 skb_deliver = hsr_pull_tag(skb_deliver);
227 if (!skb_deliver) {
228 master->dev->stats.rx_dropped++;
229 goto forward;
230 }
231#if !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
232 /* Move everything in the header that is after the HSR tag,
233 * to work around alignment problems caused by the 6-byte HSR
234 * tag. In practice, this removes/overwrites the HSR tag in
235 * the header and restores a "standard" packet.
236 */
237 memmove(skb_deliver->data - HSR_HLEN, skb_deliver->data,
238 skb_headlen(skb_deliver));
239
240 /* Adjust skb members so they correspond with the move above.
241 * This cannot possibly underflow skb->data since hsr_pull_tag()
242 * above succeeded.
243 * At this point in the protocol stack, the transport and
244 * network headers have not been set yet, and we haven't touched
245 * the mac header nor the head. So we only need to adjust data
246 * and tail:
247 */
248 skb_deliver->data -= HSR_HLEN;
249 skb_deliver->tail -= HSR_HLEN;
250#endif
251 skb_deliver->dev = master->dev;
252 hsr_addr_subst_source(hsr, skb_deliver);
253 multicast_frame = (skb_deliver->pkt_type == PACKET_MULTICAST);
254 ret = netif_rx(skb_deliver);
255 if (ret == NET_RX_DROP) {
256 master->dev->stats.rx_dropped++;
257 } else {
258 master->dev->stats.rx_packets++;
259 master->dev->stats.rx_bytes += skb->len;
260 if (multicast_frame)
261 master->dev->stats.multicast++;
262 }
263 }
264
265forward:
266 if (other_port) {
267 skb_push(skb, ETH_HLEN);
268 skb->dev = other_port->dev;
269 dev_queue_xmit(skb);
270 }
271
272 ret = RX_HANDLER_CONSUMED;
273
274finish:
275 rcu_read_unlock();
276 return ret;
277}
278
279/* Setup device to be added to the HSR bridge. */
280static int hsr_portdev_setup(struct net_device *dev, struct hsr_port *port)
281{
282 int res;
283
284 dev_hold(dev);
285 res = dev_set_promiscuity(dev, 1);
286 if (res)
287 goto fail_promiscuity;
100/* Setup device to be added to the HSR bridge. */
101static int hsr_portdev_setup(struct net_device *dev, struct hsr_port *port)
102{
103 int res;
104
105 dev_hold(dev);
106 res = dev_set_promiscuity(dev, 1);
107 if (res)
108 goto fail_promiscuity;
288 res = netdev_rx_handler_register(dev, hsr_handle_frame, port);
289 if (res)
290 goto fail_rx_handler;
291 dev_disable_lro(dev);
292
293 /* FIXME:
294 * What does net device "adjacency" mean? Should we do
295 * res = netdev_master_upper_dev_link(port->dev, port->hsr->dev); ?
296 */
297
109
110 /* FIXME:
111 * What does net device "adjacency" mean? Should we do
112 * res = netdev_master_upper_dev_link(port->dev, port->hsr->dev); ?
113 */
114
115 res = netdev_rx_handler_register(dev, hsr_handle_frame, port);
116 if (res)
117 goto fail_rx_handler;
118 dev_disable_lro(dev);
119
298 return 0;
299
300fail_rx_handler:
301 dev_set_promiscuity(dev, -1);
302fail_promiscuity:
303 dev_put(dev);
304
305 return res;

--- 28 unchanged lines hidden (view full) ---

334 port->hsr = hsr;
335 port->dev = dev;
336 port->type = type;
337
338 list_add_tail_rcu(&port->port_list, &hsr->ports);
339 synchronize_rcu();
340
341 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
120 return 0;
121
122fail_rx_handler:
123 dev_set_promiscuity(dev, -1);
124fail_promiscuity:
125 dev_put(dev);
126
127 return res;

--- 28 unchanged lines hidden (view full) ---

156 port->hsr = hsr;
157 port->dev = dev;
158 port->type = type;
159
160 list_add_tail_rcu(&port->port_list, &hsr->ports);
161 synchronize_rcu();
162
163 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
342
343 /* Set required header length */
344 if (dev->hard_header_len + HSR_HLEN > master->dev->hard_header_len)
345 master->dev->hard_header_len = dev->hard_header_len + HSR_HLEN;
346
347 netdev_update_features(master->dev);
348 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr));
349
350 return 0;
351
352fail_dev_setup:
353 kfree(port);
354 return res;

--- 25 unchanged lines hidden --- 		164 netdev_update_features(master->dev);
165 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr));
166
167 return 0;
168
169fail_dev_setup:
170 kfree(port);
171 return res;

--- 25 unchanged lines hidden ---