xref: /linux/net/hsr/hsr_framereg.c (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
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  * The HSR spec says never to forward the same frame twice on the same
8  * interface. A frame is identified by its source MAC address and its HSR
9  * sequence number. This code keeps track of senders and their sequence numbers
10  * to allow filtering of duplicate frames, and to detect HSR ring errors.
11  * Same code handles filtering of duplicates for PRP as well.
12  */
13 
14 #include <linux/if_ether.h>
15 #include <linux/etherdevice.h>
16 #include <linux/slab.h>
17 #include <linux/rculist.h>
18 #include "hsr_main.h"
19 #include "hsr_framereg.h"
20 #include "hsr_netlink.h"
21 
22 /* seq_nr_after(a, b) - return true if a is after (higher in sequence than) b,
23  * false otherwise.
24  */
seq_nr_after(u16 a,u16 b)25 static bool seq_nr_after(u16 a, u16 b)
26 {
27 	/* Remove inconsistency where
28 	 * seq_nr_after(a, b) == seq_nr_before(a, b)
29 	 */
30 	if ((int)b - a == 32768)
31 		return false;
32 
33 	return (((s16)(b - a)) < 0);
34 }
35 
36 #define seq_nr_before(a, b)		seq_nr_after((b), (a))
37 #define seq_nr_before_or_eq(a, b)	(!seq_nr_after((a), (b)))
38 
hsr_addr_is_redbox(struct hsr_priv * hsr,unsigned char * addr)39 bool hsr_addr_is_redbox(struct hsr_priv *hsr, unsigned char *addr)
40 {
41 	if (!hsr->redbox || !is_valid_ether_addr(hsr->macaddress_redbox))
42 		return false;
43 
44 	return ether_addr_equal(addr, hsr->macaddress_redbox);
45 }
46 
hsr_addr_is_self(struct hsr_priv * hsr,unsigned char * addr)47 bool hsr_addr_is_self(struct hsr_priv *hsr, unsigned char *addr)
48 {
49 	struct hsr_self_node *sn;
50 	bool ret = false;
51 
52 	rcu_read_lock();
53 	sn = rcu_dereference(hsr->self_node);
54 	if (!sn) {
55 		WARN_ONCE(1, "HSR: No self node\n");
56 		goto out;
57 	}
58 
59 	if (ether_addr_equal(addr, sn->macaddress_A) ||
60 	    ether_addr_equal(addr, sn->macaddress_B))
61 		ret = true;
62 out:
63 	rcu_read_unlock();
64 	return ret;
65 }
66 
67 /* Search for mac entry. Caller must hold rcu read lock.
68  */
find_node_by_addr_A(struct list_head * node_db,const unsigned char addr[ETH_ALEN])69 static struct hsr_node *find_node_by_addr_A(struct list_head *node_db,
70 					    const unsigned char addr[ETH_ALEN])
71 {
72 	struct hsr_node *node;
73 
74 	list_for_each_entry_rcu(node, node_db, mac_list) {
75 		if (ether_addr_equal(node->macaddress_A, addr))
76 			return node;
77 	}
78 
79 	return NULL;
80 }
81 
82 /* Check if node for a given MAC address is already present in data base
83  */
hsr_is_node_in_db(struct list_head * node_db,const unsigned char addr[ETH_ALEN])84 bool hsr_is_node_in_db(struct list_head *node_db,
85 		       const unsigned char addr[ETH_ALEN])
86 {
87 	return !!find_node_by_addr_A(node_db, addr);
88 }
89 
90 /* Helper for device init; the self_node is used in hsr_rcv() to recognize
91  * frames from self that's been looped over the HSR ring.
92  */
hsr_create_self_node(struct hsr_priv * hsr,const unsigned char addr_a[ETH_ALEN],const unsigned char addr_b[ETH_ALEN])93 int hsr_create_self_node(struct hsr_priv *hsr,
94 			 const unsigned char addr_a[ETH_ALEN],
95 			 const unsigned char addr_b[ETH_ALEN])
96 {
97 	struct hsr_self_node *sn, *old;
98 
99 	sn = kmalloc(sizeof(*sn), GFP_KERNEL);
100 	if (!sn)
101 		return -ENOMEM;
102 
103 	ether_addr_copy(sn->macaddress_A, addr_a);
104 	ether_addr_copy(sn->macaddress_B, addr_b);
105 
106 	spin_lock_bh(&hsr->list_lock);
107 	old = rcu_replace_pointer(hsr->self_node, sn,
108 				  lockdep_is_held(&hsr->list_lock));
109 	spin_unlock_bh(&hsr->list_lock);
110 
111 	if (old)
112 		kfree_rcu(old, rcu_head);
113 	return 0;
114 }
115 
hsr_del_self_node(struct hsr_priv * hsr)116 void hsr_del_self_node(struct hsr_priv *hsr)
117 {
118 	struct hsr_self_node *old;
119 
120 	spin_lock_bh(&hsr->list_lock);
121 	old = rcu_replace_pointer(hsr->self_node, NULL,
122 				  lockdep_is_held(&hsr->list_lock));
123 	spin_unlock_bh(&hsr->list_lock);
124 	if (old)
125 		kfree_rcu(old, rcu_head);
126 }
127 
hsr_del_nodes(struct list_head * node_db)128 void hsr_del_nodes(struct list_head *node_db)
129 {
130 	struct hsr_node *node;
131 	struct hsr_node *tmp;
132 
133 	list_for_each_entry_safe(node, tmp, node_db, mac_list)
134 		kfree(node);
135 }
136 
prp_handle_san_frame(bool san,enum hsr_port_type port,struct hsr_node * node)137 void prp_handle_san_frame(bool san, enum hsr_port_type port,
138 			  struct hsr_node *node)
139 {
140 	/* Mark if the SAN node is over LAN_A or LAN_B */
141 	if (port == HSR_PT_SLAVE_A) {
142 		node->san_a = true;
143 		return;
144 	}
145 
146 	if (port == HSR_PT_SLAVE_B)
147 		node->san_b = true;
148 }
149 
150 /* Allocate an hsr_node and add it to node_db. 'addr' is the node's address_A;
151  * seq_out is used to initialize filtering of outgoing duplicate frames
152  * originating from the newly added node.
153  */
hsr_add_node(struct hsr_priv * hsr,struct list_head * node_db,unsigned char addr[],u16 seq_out,bool san,enum hsr_port_type rx_port)154 static struct hsr_node *hsr_add_node(struct hsr_priv *hsr,
155 				     struct list_head *node_db,
156 				     unsigned char addr[],
157 				     u16 seq_out, bool san,
158 				     enum hsr_port_type rx_port)
159 {
160 	struct hsr_node *new_node, *node;
161 	unsigned long now;
162 	int i;
163 
164 	new_node = kzalloc(sizeof(*new_node), GFP_ATOMIC);
165 	if (!new_node)
166 		return NULL;
167 
168 	ether_addr_copy(new_node->macaddress_A, addr);
169 	spin_lock_init(&new_node->seq_out_lock);
170 
171 	/* We are only interested in time diffs here, so use current jiffies
172 	 * as initialization. (0 could trigger an spurious ring error warning).
173 	 */
174 	now = jiffies;
175 	for (i = 0; i < HSR_PT_PORTS; i++) {
176 		new_node->time_in[i] = now;
177 		new_node->time_out[i] = now;
178 	}
179 	for (i = 0; i < HSR_PT_PORTS; i++)
180 		new_node->seq_out[i] = seq_out;
181 
182 	if (san && hsr->proto_ops->handle_san_frame)
183 		hsr->proto_ops->handle_san_frame(san, rx_port, new_node);
184 
185 	spin_lock_bh(&hsr->list_lock);
186 	list_for_each_entry_rcu(node, node_db, mac_list,
187 				lockdep_is_held(&hsr->list_lock)) {
188 		if (ether_addr_equal(node->macaddress_A, addr))
189 			goto out;
190 		if (ether_addr_equal(node->macaddress_B, addr))
191 			goto out;
192 	}
193 	list_add_tail_rcu(&new_node->mac_list, node_db);
194 	spin_unlock_bh(&hsr->list_lock);
195 	return new_node;
196 out:
197 	spin_unlock_bh(&hsr->list_lock);
198 	kfree(new_node);
199 	return node;
200 }
201 
prp_update_san_info(struct hsr_node * node,bool is_sup)202 void prp_update_san_info(struct hsr_node *node, bool is_sup)
203 {
204 	if (!is_sup)
205 		return;
206 
207 	node->san_a = false;
208 	node->san_b = false;
209 }
210 
211 /* Get the hsr_node from which 'skb' was sent.
212  */
hsr_get_node(struct hsr_port * port,struct list_head * node_db,struct sk_buff * skb,bool is_sup,enum hsr_port_type rx_port)213 struct hsr_node *hsr_get_node(struct hsr_port *port, struct list_head *node_db,
214 			      struct sk_buff *skb, bool is_sup,
215 			      enum hsr_port_type rx_port)
216 {
217 	struct hsr_priv *hsr = port->hsr;
218 	struct hsr_node *node;
219 	struct ethhdr *ethhdr;
220 	struct prp_rct *rct;
221 	bool san = false;
222 	u16 seq_out;
223 
224 	if (!skb_mac_header_was_set(skb))
225 		return NULL;
226 
227 	ethhdr = (struct ethhdr *)skb_mac_header(skb);
228 
229 	list_for_each_entry_rcu(node, node_db, mac_list) {
230 		if (ether_addr_equal(node->macaddress_A, ethhdr->h_source)) {
231 			if (hsr->proto_ops->update_san_info)
232 				hsr->proto_ops->update_san_info(node, is_sup);
233 			return node;
234 		}
235 		if (ether_addr_equal(node->macaddress_B, ethhdr->h_source)) {
236 			if (hsr->proto_ops->update_san_info)
237 				hsr->proto_ops->update_san_info(node, is_sup);
238 			return node;
239 		}
240 	}
241 
242 	/* Check if required node is not in proxy nodes table */
243 	list_for_each_entry_rcu(node, &hsr->proxy_node_db, mac_list) {
244 		if (ether_addr_equal(node->macaddress_A, ethhdr->h_source)) {
245 			if (hsr->proto_ops->update_san_info)
246 				hsr->proto_ops->update_san_info(node, is_sup);
247 			return node;
248 		}
249 	}
250 
251 	/* Everyone may create a node entry, connected node to a HSR/PRP
252 	 * device.
253 	 */
254 	if (ethhdr->h_proto == htons(ETH_P_PRP) ||
255 	    ethhdr->h_proto == htons(ETH_P_HSR)) {
256 		/* Check if skb contains hsr_ethhdr */
257 		if (skb->mac_len < sizeof(struct hsr_ethhdr))
258 			return NULL;
259 
260 		/* Use the existing sequence_nr from the tag as starting point
261 		 * for filtering duplicate frames.
262 		 */
263 		seq_out = hsr_get_skb_sequence_nr(skb) - 1;
264 	} else {
265 		rct = skb_get_PRP_rct(skb);
266 		if (rct && prp_check_lsdu_size(skb, rct, is_sup)) {
267 			seq_out = prp_get_skb_sequence_nr(rct);
268 		} else {
269 			if (rx_port != HSR_PT_MASTER)
270 				san = true;
271 			seq_out = HSR_SEQNR_START;
272 		}
273 	}
274 
275 	return hsr_add_node(hsr, node_db, ethhdr->h_source, seq_out,
276 			    san, rx_port);
277 }
278 
279 /* Use the Supervision frame's info about an eventual macaddress_B for merging
280  * nodes that has previously had their macaddress_B registered as a separate
281  * node.
282  */
hsr_handle_sup_frame(struct hsr_frame_info * frame)283 void hsr_handle_sup_frame(struct hsr_frame_info *frame)
284 {
285 	struct hsr_node *node_curr = frame->node_src;
286 	struct hsr_port *port_rcv = frame->port_rcv;
287 	struct hsr_priv *hsr = port_rcv->hsr;
288 	struct hsr_sup_payload *hsr_sp;
289 	struct hsr_sup_tlv *hsr_sup_tlv;
290 	struct hsr_node *node_real;
291 	struct sk_buff *skb = NULL;
292 	struct list_head *node_db;
293 	struct ethhdr *ethhdr;
294 	int i;
295 	unsigned int pull_size = 0;
296 	unsigned int total_pull_size = 0;
297 
298 	/* Here either frame->skb_hsr or frame->skb_prp should be
299 	 * valid as supervision frame always will have protocol
300 	 * header info.
301 	 */
302 	if (frame->skb_hsr)
303 		skb = frame->skb_hsr;
304 	else if (frame->skb_prp)
305 		skb = frame->skb_prp;
306 	else if (frame->skb_std)
307 		skb = frame->skb_std;
308 	if (!skb)
309 		return;
310 
311 	/* Leave the ethernet header. */
312 	pull_size = sizeof(struct ethhdr);
313 	skb_pull(skb, pull_size);
314 	total_pull_size += pull_size;
315 
316 	ethhdr = (struct ethhdr *)skb_mac_header(skb);
317 
318 	/* And leave the HSR tag. */
319 	if (ethhdr->h_proto == htons(ETH_P_HSR)) {
320 		pull_size = sizeof(struct hsr_tag);
321 		skb_pull(skb, pull_size);
322 		total_pull_size += pull_size;
323 	}
324 
325 	/* And leave the HSR sup tag. */
326 	pull_size = sizeof(struct hsr_sup_tag);
327 	skb_pull(skb, pull_size);
328 	total_pull_size += pull_size;
329 
330 	/* get HSR sup payload */
331 	hsr_sp = (struct hsr_sup_payload *)skb->data;
332 
333 	/* Merge node_curr (registered on macaddress_B) into node_real */
334 	node_db = &port_rcv->hsr->node_db;
335 	node_real = find_node_by_addr_A(node_db, hsr_sp->macaddress_A);
336 	if (!node_real)
337 		/* No frame received from AddrA of this node yet */
338 		node_real = hsr_add_node(hsr, node_db, hsr_sp->macaddress_A,
339 					 HSR_SEQNR_START - 1, true,
340 					 port_rcv->type);
341 	if (!node_real)
342 		goto done; /* No mem */
343 	if (node_real == node_curr)
344 		/* Node has already been merged */
345 		goto done;
346 
347 	/* Leave the first HSR sup payload. */
348 	pull_size = sizeof(struct hsr_sup_payload);
349 	skb_pull(skb, pull_size);
350 	total_pull_size += pull_size;
351 
352 	/* Get second supervision tlv */
353 	hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
354 	/* And check if it is a redbox mac TLV */
355 	if (hsr_sup_tlv->HSR_TLV_type == PRP_TLV_REDBOX_MAC) {
356 		/* We could stop here after pushing hsr_sup_payload,
357 		 * or proceed and allow macaddress_B and for redboxes.
358 		 */
359 		/* Sanity check length */
360 		if (hsr_sup_tlv->HSR_TLV_length != 6)
361 			goto done;
362 
363 		/* Leave the second HSR sup tlv. */
364 		pull_size = sizeof(struct hsr_sup_tlv);
365 		skb_pull(skb, pull_size);
366 		total_pull_size += pull_size;
367 
368 		/* Get redbox mac address. */
369 		hsr_sp = (struct hsr_sup_payload *)skb->data;
370 
371 		/* Check if redbox mac and node mac are equal. */
372 		if (!ether_addr_equal(node_real->macaddress_A, hsr_sp->macaddress_A)) {
373 			/* This is a redbox supervision frame for a VDAN! */
374 			goto done;
375 		}
376 	}
377 
378 	ether_addr_copy(node_real->macaddress_B, ethhdr->h_source);
379 	spin_lock_bh(&node_real->seq_out_lock);
380 	for (i = 0; i < HSR_PT_PORTS; i++) {
381 		if (!node_curr->time_in_stale[i] &&
382 		    time_after(node_curr->time_in[i], node_real->time_in[i])) {
383 			node_real->time_in[i] = node_curr->time_in[i];
384 			node_real->time_in_stale[i] =
385 						node_curr->time_in_stale[i];
386 		}
387 		if (seq_nr_after(node_curr->seq_out[i], node_real->seq_out[i]))
388 			node_real->seq_out[i] = node_curr->seq_out[i];
389 	}
390 	spin_unlock_bh(&node_real->seq_out_lock);
391 	node_real->addr_B_port = port_rcv->type;
392 
393 	spin_lock_bh(&hsr->list_lock);
394 	if (!node_curr->removed) {
395 		list_del_rcu(&node_curr->mac_list);
396 		node_curr->removed = true;
397 		kfree_rcu(node_curr, rcu_head);
398 	}
399 	spin_unlock_bh(&hsr->list_lock);
400 
401 done:
402 	/* Push back here */
403 	skb_push(skb, total_pull_size);
404 }
405 
406 /* 'skb' is a frame meant for this host, that is to be passed to upper layers.
407  *
408  * If the frame was sent by a node's B interface, replace the source
409  * address with that node's "official" address (macaddress_A) so that upper
410  * layers recognize where it came from.
411  */
hsr_addr_subst_source(struct hsr_node * node,struct sk_buff * skb)412 void hsr_addr_subst_source(struct hsr_node *node, struct sk_buff *skb)
413 {
414 	if (!skb_mac_header_was_set(skb)) {
415 		WARN_ONCE(1, "%s: Mac header not set\n", __func__);
416 		return;
417 	}
418 
419 	memcpy(&eth_hdr(skb)->h_source, node->macaddress_A, ETH_ALEN);
420 }
421 
422 /* 'skb' is a frame meant for another host.
423  * 'port' is the outgoing interface
424  *
425  * Substitute the target (dest) MAC address if necessary, so the it matches the
426  * recipient interface MAC address, regardless of whether that is the
427  * recipient's A or B interface.
428  * This is needed to keep the packets flowing through switches that learn on
429  * which "side" the different interfaces are.
430  */
hsr_addr_subst_dest(struct hsr_node * node_src,struct sk_buff * skb,struct hsr_port * port)431 void hsr_addr_subst_dest(struct hsr_node *node_src, struct sk_buff *skb,
432 			 struct hsr_port *port)
433 {
434 	struct hsr_node *node_dst;
435 
436 	if (!skb_mac_header_was_set(skb)) {
437 		WARN_ONCE(1, "%s: Mac header not set\n", __func__);
438 		return;
439 	}
440 
441 	if (!is_unicast_ether_addr(eth_hdr(skb)->h_dest))
442 		return;
443 
444 	node_dst = find_node_by_addr_A(&port->hsr->node_db,
445 				       eth_hdr(skb)->h_dest);
446 	if (!node_dst && port->hsr->redbox)
447 		node_dst = find_node_by_addr_A(&port->hsr->proxy_node_db,
448 					       eth_hdr(skb)->h_dest);
449 
450 	if (!node_dst) {
451 		if (port->hsr->prot_version != PRP_V1 && net_ratelimit())
452 			netdev_err(skb->dev, "%s: Unknown node\n", __func__);
453 		return;
454 	}
455 	if (port->type != node_dst->addr_B_port)
456 		return;
457 
458 	if (is_valid_ether_addr(node_dst->macaddress_B))
459 		ether_addr_copy(eth_hdr(skb)->h_dest, node_dst->macaddress_B);
460 }
461 
hsr_register_frame_in(struct hsr_node * node,struct hsr_port * port,u16 sequence_nr)462 void hsr_register_frame_in(struct hsr_node *node, struct hsr_port *port,
463 			   u16 sequence_nr)
464 {
465 	/* Don't register incoming frames without a valid sequence number. This
466 	 * ensures entries of restarted nodes gets pruned so that they can
467 	 * re-register and resume communications.
468 	 */
469 	if (!(port->dev->features & NETIF_F_HW_HSR_TAG_RM) &&
470 	    seq_nr_before(sequence_nr, node->seq_out[port->type]))
471 		return;
472 
473 	node->time_in[port->type] = jiffies;
474 	node->time_in_stale[port->type] = false;
475 }
476 
477 /* 'skb' is a HSR Ethernet frame (with a HSR tag inserted), with a valid
478  * ethhdr->h_source address and skb->mac_header set.
479  *
480  * Return:
481  *	 1 if frame can be shown to have been sent recently on this interface,
482  *	 0 otherwise, or
483  *	 negative error code on error
484  */
hsr_register_frame_out(struct hsr_port * port,struct hsr_node * node,u16 sequence_nr)485 int hsr_register_frame_out(struct hsr_port *port, struct hsr_node *node,
486 			   u16 sequence_nr)
487 {
488 	spin_lock_bh(&node->seq_out_lock);
489 	if (seq_nr_before_or_eq(sequence_nr, node->seq_out[port->type]) &&
490 	    time_is_after_jiffies(node->time_out[port->type] +
491 	    msecs_to_jiffies(HSR_ENTRY_FORGET_TIME))) {
492 		spin_unlock_bh(&node->seq_out_lock);
493 		return 1;
494 	}
495 
496 	node->time_out[port->type] = jiffies;
497 	node->seq_out[port->type] = sequence_nr;
498 	spin_unlock_bh(&node->seq_out_lock);
499 	return 0;
500 }
501 
get_late_port(struct hsr_priv * hsr,struct hsr_node * node)502 static struct hsr_port *get_late_port(struct hsr_priv *hsr,
503 				      struct hsr_node *node)
504 {
505 	if (node->time_in_stale[HSR_PT_SLAVE_A])
506 		return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
507 	if (node->time_in_stale[HSR_PT_SLAVE_B])
508 		return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
509 
510 	if (time_after(node->time_in[HSR_PT_SLAVE_B],
511 		       node->time_in[HSR_PT_SLAVE_A] +
512 					msecs_to_jiffies(MAX_SLAVE_DIFF)))
513 		return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
514 	if (time_after(node->time_in[HSR_PT_SLAVE_A],
515 		       node->time_in[HSR_PT_SLAVE_B] +
516 					msecs_to_jiffies(MAX_SLAVE_DIFF)))
517 		return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
518 
519 	return NULL;
520 }
521 
522 /* Remove stale sequence_nr records. Called by timer every
523  * HSR_LIFE_CHECK_INTERVAL (two seconds or so).
524  */
hsr_prune_nodes(struct timer_list * t)525 void hsr_prune_nodes(struct timer_list *t)
526 {
527 	struct hsr_priv *hsr = from_timer(hsr, t, prune_timer);
528 	struct hsr_node *node;
529 	struct hsr_node *tmp;
530 	struct hsr_port *port;
531 	unsigned long timestamp;
532 	unsigned long time_a, time_b;
533 
534 	spin_lock_bh(&hsr->list_lock);
535 	list_for_each_entry_safe(node, tmp, &hsr->node_db, mac_list) {
536 		/* Don't prune own node. Neither time_in[HSR_PT_SLAVE_A]
537 		 * nor time_in[HSR_PT_SLAVE_B], will ever be updated for
538 		 * the master port. Thus the master node will be repeatedly
539 		 * pruned leading to packet loss.
540 		 */
541 		if (hsr_addr_is_self(hsr, node->macaddress_A))
542 			continue;
543 
544 		/* Shorthand */
545 		time_a = node->time_in[HSR_PT_SLAVE_A];
546 		time_b = node->time_in[HSR_PT_SLAVE_B];
547 
548 		/* Check for timestamps old enough to risk wrap-around */
549 		if (time_after(jiffies, time_a + MAX_JIFFY_OFFSET / 2))
550 			node->time_in_stale[HSR_PT_SLAVE_A] = true;
551 		if (time_after(jiffies, time_b + MAX_JIFFY_OFFSET / 2))
552 			node->time_in_stale[HSR_PT_SLAVE_B] = true;
553 
554 		/* Get age of newest frame from node.
555 		 * At least one time_in is OK here; nodes get pruned long
556 		 * before both time_ins can get stale
557 		 */
558 		timestamp = time_a;
559 		if (node->time_in_stale[HSR_PT_SLAVE_A] ||
560 		    (!node->time_in_stale[HSR_PT_SLAVE_B] &&
561 		    time_after(time_b, time_a)))
562 			timestamp = time_b;
563 
564 		/* Warn of ring error only as long as we get frames at all */
565 		if (time_is_after_jiffies(timestamp +
566 				msecs_to_jiffies(1.5 * MAX_SLAVE_DIFF))) {
567 			rcu_read_lock();
568 			port = get_late_port(hsr, node);
569 			if (port)
570 				hsr_nl_ringerror(hsr, node->macaddress_A, port);
571 			rcu_read_unlock();
572 		}
573 
574 		/* Prune old entries */
575 		if (time_is_before_jiffies(timestamp +
576 				msecs_to_jiffies(HSR_NODE_FORGET_TIME))) {
577 			hsr_nl_nodedown(hsr, node->macaddress_A);
578 			if (!node->removed) {
579 				list_del_rcu(&node->mac_list);
580 				node->removed = true;
581 				/* Note that we need to free this entry later: */
582 				kfree_rcu(node, rcu_head);
583 			}
584 		}
585 	}
586 	spin_unlock_bh(&hsr->list_lock);
587 
588 	/* Restart timer */
589 	mod_timer(&hsr->prune_timer,
590 		  jiffies + msecs_to_jiffies(PRUNE_PERIOD));
591 }
592 
hsr_prune_proxy_nodes(struct timer_list * t)593 void hsr_prune_proxy_nodes(struct timer_list *t)
594 {
595 	struct hsr_priv *hsr = from_timer(hsr, t, prune_proxy_timer);
596 	unsigned long timestamp;
597 	struct hsr_node *node;
598 	struct hsr_node *tmp;
599 
600 	spin_lock_bh(&hsr->list_lock);
601 	list_for_each_entry_safe(node, tmp, &hsr->proxy_node_db, mac_list) {
602 		/* Don't prune RedBox node. */
603 		if (hsr_addr_is_redbox(hsr, node->macaddress_A))
604 			continue;
605 
606 		timestamp = node->time_in[HSR_PT_INTERLINK];
607 
608 		/* Prune old entries */
609 		if (time_is_before_jiffies(timestamp +
610 				msecs_to_jiffies(HSR_PROXY_NODE_FORGET_TIME))) {
611 			hsr_nl_nodedown(hsr, node->macaddress_A);
612 			if (!node->removed) {
613 				list_del_rcu(&node->mac_list);
614 				node->removed = true;
615 				/* Note that we need to free this entry later: */
616 				kfree_rcu(node, rcu_head);
617 			}
618 		}
619 	}
620 
621 	spin_unlock_bh(&hsr->list_lock);
622 
623 	/* Restart timer */
624 	mod_timer(&hsr->prune_proxy_timer,
625 		  jiffies + msecs_to_jiffies(PRUNE_PROXY_PERIOD));
626 }
627 
hsr_get_next_node(struct hsr_priv * hsr,void * _pos,unsigned char addr[ETH_ALEN])628 void *hsr_get_next_node(struct hsr_priv *hsr, void *_pos,
629 			unsigned char addr[ETH_ALEN])
630 {
631 	struct hsr_node *node;
632 
633 	if (!_pos) {
634 		node = list_first_or_null_rcu(&hsr->node_db,
635 					      struct hsr_node, mac_list);
636 		if (node)
637 			ether_addr_copy(addr, node->macaddress_A);
638 		return node;
639 	}
640 
641 	node = _pos;
642 	list_for_each_entry_continue_rcu(node, &hsr->node_db, mac_list) {
643 		ether_addr_copy(addr, node->macaddress_A);
644 		return node;
645 	}
646 
647 	return NULL;
648 }
649 
hsr_get_node_data(struct hsr_priv * hsr,const unsigned char * addr,unsigned char addr_b[ETH_ALEN],unsigned int * addr_b_ifindex,int * if1_age,u16 * if1_seq,int * if2_age,u16 * if2_seq)650 int hsr_get_node_data(struct hsr_priv *hsr,
651 		      const unsigned char *addr,
652 		      unsigned char addr_b[ETH_ALEN],
653 		      unsigned int *addr_b_ifindex,
654 		      int *if1_age,
655 		      u16 *if1_seq,
656 		      int *if2_age,
657 		      u16 *if2_seq)
658 {
659 	struct hsr_node *node;
660 	struct hsr_port *port;
661 	unsigned long tdiff;
662 
663 	node = find_node_by_addr_A(&hsr->node_db, addr);
664 	if (!node)
665 		return -ENOENT;
666 
667 	ether_addr_copy(addr_b, node->macaddress_B);
668 
669 	tdiff = jiffies - node->time_in[HSR_PT_SLAVE_A];
670 	if (node->time_in_stale[HSR_PT_SLAVE_A])
671 		*if1_age = INT_MAX;
672 #if HZ <= MSEC_PER_SEC
673 	else if (tdiff > msecs_to_jiffies(INT_MAX))
674 		*if1_age = INT_MAX;
675 #endif
676 	else
677 		*if1_age = jiffies_to_msecs(tdiff);
678 
679 	tdiff = jiffies - node->time_in[HSR_PT_SLAVE_B];
680 	if (node->time_in_stale[HSR_PT_SLAVE_B])
681 		*if2_age = INT_MAX;
682 #if HZ <= MSEC_PER_SEC
683 	else if (tdiff > msecs_to_jiffies(INT_MAX))
684 		*if2_age = INT_MAX;
685 #endif
686 	else
687 		*if2_age = jiffies_to_msecs(tdiff);
688 
689 	/* Present sequence numbers as if they were incoming on interface */
690 	*if1_seq = node->seq_out[HSR_PT_SLAVE_B];
691 	*if2_seq = node->seq_out[HSR_PT_SLAVE_A];
692 
693 	if (node->addr_B_port != HSR_PT_NONE) {
694 		port = hsr_port_get_hsr(hsr, node->addr_B_port);
695 		*addr_b_ifindex = port->dev->ifindex;
696 	} else {
697 		*addr_b_ifindex = -1;
698 	}
699 
700 	return 0;
701 }
702