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 <kunit/visibility.h>
15 #include <linux/if_ether.h>
16 #include <linux/etherdevice.h>
17 #include <linux/slab.h>
18 #include <linux/rculist.h>
19 #include "hsr_main.h"
20 #include "hsr_framereg.h"
21 #include "hsr_netlink.h"
22
hsr_addr_is_redbox(struct hsr_priv * hsr,unsigned char * addr)23 bool hsr_addr_is_redbox(struct hsr_priv *hsr, unsigned char *addr)
24 {
25 if (!hsr->redbox || !is_valid_ether_addr(hsr->macaddress_redbox))
26 return false;
27
28 return ether_addr_equal(addr, hsr->macaddress_redbox);
29 }
30
hsr_addr_is_self(struct hsr_priv * hsr,unsigned char * addr)31 bool hsr_addr_is_self(struct hsr_priv *hsr, unsigned char *addr)
32 {
33 struct hsr_self_node *sn;
34 bool ret = false;
35
36 rcu_read_lock();
37 sn = rcu_dereference(hsr->self_node);
38 if (!sn) {
39 WARN_ONCE(1, "HSR: No self node\n");
40 goto out;
41 }
42
43 if (ether_addr_equal(addr, sn->macaddress_A) ||
44 ether_addr_equal(addr, sn->macaddress_B))
45 ret = true;
46 out:
47 rcu_read_unlock();
48 return ret;
49 }
50
51 /* Search for mac entry. Caller must hold rcu read lock.
52 */
find_node_by_addr_A(struct list_head * node_db,const unsigned char addr[ETH_ALEN])53 static struct hsr_node *find_node_by_addr_A(struct list_head *node_db,
54 const unsigned char addr[ETH_ALEN])
55 {
56 struct hsr_node *node;
57
58 list_for_each_entry_rcu(node, node_db, mac_list) {
59 if (ether_addr_equal(node->macaddress_A, addr))
60 return node;
61 }
62
63 return NULL;
64 }
65
66 /* Check if node for a given MAC address is already present in data base
67 */
hsr_is_node_in_db(struct list_head * node_db,const unsigned char addr[ETH_ALEN])68 bool hsr_is_node_in_db(struct list_head *node_db,
69 const unsigned char addr[ETH_ALEN])
70 {
71 return !!find_node_by_addr_A(node_db, addr);
72 }
73
74 /* Helper for device init; the self_node is used in hsr_rcv() to recognize
75 * frames from self that's been looped over the HSR ring.
76 */
hsr_create_self_node(struct hsr_priv * hsr,const unsigned char addr_a[ETH_ALEN],const unsigned char addr_b[ETH_ALEN])77 int hsr_create_self_node(struct hsr_priv *hsr,
78 const unsigned char addr_a[ETH_ALEN],
79 const unsigned char addr_b[ETH_ALEN])
80 {
81 struct hsr_self_node *sn, *old;
82
83 sn = kmalloc_obj(*sn);
84 if (!sn)
85 return -ENOMEM;
86
87 ether_addr_copy(sn->macaddress_A, addr_a);
88 ether_addr_copy(sn->macaddress_B, addr_b);
89
90 spin_lock_bh(&hsr->list_lock);
91 old = rcu_replace_pointer(hsr->self_node, sn,
92 lockdep_is_held(&hsr->list_lock));
93 spin_unlock_bh(&hsr->list_lock);
94
95 if (old)
96 kfree_rcu(old, rcu_head);
97 return 0;
98 }
99
hsr_del_self_node(struct hsr_priv * hsr)100 void hsr_del_self_node(struct hsr_priv *hsr)
101 {
102 struct hsr_self_node *old;
103
104 spin_lock_bh(&hsr->list_lock);
105 old = rcu_replace_pointer(hsr->self_node, NULL,
106 lockdep_is_held(&hsr->list_lock));
107 spin_unlock_bh(&hsr->list_lock);
108 if (old)
109 kfree_rcu(old, rcu_head);
110 }
111
hsr_free_node(struct hsr_node * node)112 static void hsr_free_node(struct hsr_node *node)
113 {
114 xa_destroy(&node->seq_blocks);
115 kfree(node->block_buf);
116 kfree(node);
117 }
118
hsr_free_node_rcu(struct rcu_head * rn)119 static void hsr_free_node_rcu(struct rcu_head *rn)
120 {
121 struct hsr_node *node = container_of(rn, struct hsr_node, rcu_head);
122
123 hsr_free_node(node);
124 }
125
hsr_lock_seq_out_pair(struct hsr_node * node_a,struct hsr_node * node_b)126 static void hsr_lock_seq_out_pair(struct hsr_node *node_a,
127 struct hsr_node *node_b)
128 {
129 if (node_a == node_b) {
130 spin_lock_bh(&node_a->seq_out_lock);
131 return;
132 }
133
134 if (node_a < node_b) {
135 spin_lock_bh(&node_a->seq_out_lock);
136 spin_lock_nested(&node_b->seq_out_lock, SINGLE_DEPTH_NESTING);
137 } else {
138 spin_lock_bh(&node_b->seq_out_lock);
139 spin_lock_nested(&node_a->seq_out_lock, SINGLE_DEPTH_NESTING);
140 }
141 }
142
hsr_unlock_seq_out_pair(struct hsr_node * node_a,struct hsr_node * node_b)143 static void hsr_unlock_seq_out_pair(struct hsr_node *node_a,
144 struct hsr_node *node_b)
145 {
146 if (node_a == node_b) {
147 spin_unlock_bh(&node_a->seq_out_lock);
148 return;
149 }
150
151 if (node_a < node_b) {
152 spin_unlock(&node_b->seq_out_lock);
153 spin_unlock_bh(&node_a->seq_out_lock);
154 } else {
155 spin_unlock(&node_a->seq_out_lock);
156 spin_unlock_bh(&node_b->seq_out_lock);
157 }
158 }
159
hsr_del_nodes(struct list_head * node_db)160 void hsr_del_nodes(struct list_head *node_db)
161 {
162 struct hsr_node *node;
163 struct hsr_node *tmp;
164
165 list_for_each_entry_safe(node, tmp, node_db, mac_list) {
166 list_del(&node->mac_list);
167 hsr_free_node(node);
168 }
169 }
170
prp_handle_san_frame(bool san,enum hsr_port_type port,struct hsr_node * node)171 void prp_handle_san_frame(bool san, enum hsr_port_type port,
172 struct hsr_node *node)
173 {
174 /* Mark if the SAN node is over LAN_A or LAN_B */
175 if (port == HSR_PT_SLAVE_A) {
176 node->san_a = true;
177 return;
178 }
179
180 if (port == HSR_PT_SLAVE_B)
181 node->san_b = true;
182 }
183
184 /* Allocate an hsr_node and add it to node_db. 'addr' is the node's address_A.
185 */
hsr_add_node(struct hsr_priv * hsr,struct list_head * node_db,unsigned char addr[],bool san,enum hsr_port_type rx_port)186 static struct hsr_node *hsr_add_node(struct hsr_priv *hsr,
187 struct list_head *node_db,
188 unsigned char addr[], bool san,
189 enum hsr_port_type rx_port)
190 {
191 struct hsr_node *new_node, *node = NULL;
192 unsigned long now;
193 size_t block_sz;
194 int i;
195
196 new_node = kzalloc_obj(*new_node, GFP_ATOMIC);
197 if (!new_node)
198 return NULL;
199
200 ether_addr_copy(new_node->macaddress_A, addr);
201 spin_lock_init(&new_node->seq_out_lock);
202
203 if (hsr->prot_version == PRP_V1)
204 new_node->seq_port_cnt = 1;
205 else
206 new_node->seq_port_cnt = HSR_PT_PORTS - 1;
207
208 block_sz = hsr_seq_block_size(new_node);
209 new_node->block_buf = kcalloc(HSR_MAX_SEQ_BLOCKS, block_sz, GFP_ATOMIC);
210 if (!new_node->block_buf)
211 goto free;
212
213 xa_init(&new_node->seq_blocks);
214
215 /* We are only interested in time diffs here, so use current jiffies
216 * as initialization. (0 could trigger an spurious ring error warning).
217 */
218 now = jiffies;
219 for (i = 0; i < HSR_PT_PORTS; i++) {
220 new_node->time_in[i] = now;
221 }
222
223 if (san && hsr->proto_ops->handle_san_frame)
224 hsr->proto_ops->handle_san_frame(san, rx_port, new_node);
225
226 spin_lock_bh(&hsr->list_lock);
227 list_for_each_entry_rcu(node, node_db, mac_list,
228 lockdep_is_held(&hsr->list_lock)) {
229 if (ether_addr_equal(node->macaddress_A, addr))
230 goto out;
231 if (ether_addr_equal(node->macaddress_B, addr))
232 goto out;
233 }
234 list_add_tail_rcu(&new_node->mac_list, node_db);
235 spin_unlock_bh(&hsr->list_lock);
236 return new_node;
237 out:
238 spin_unlock_bh(&hsr->list_lock);
239 kfree(new_node->block_buf);
240 free:
241 kfree(new_node);
242 return node;
243 }
244
prp_update_san_info(struct hsr_node * node,bool is_sup)245 void prp_update_san_info(struct hsr_node *node, bool is_sup)
246 {
247 if (!is_sup)
248 return;
249
250 node->san_a = false;
251 node->san_b = false;
252 }
253
254 /* Get the hsr_node from which 'skb' was sent.
255 */
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)256 struct hsr_node *hsr_get_node(struct hsr_port *port, struct list_head *node_db,
257 struct sk_buff *skb, bool is_sup,
258 enum hsr_port_type rx_port)
259 {
260 struct hsr_priv *hsr = port->hsr;
261 struct hsr_node *node;
262 struct ethhdr *ethhdr;
263 struct prp_rct *rct;
264 bool san = false;
265
266 if (!skb_mac_header_was_set(skb))
267 return NULL;
268
269 ethhdr = (struct ethhdr *)skb_mac_header(skb);
270
271 list_for_each_entry_rcu(node, node_db, mac_list) {
272 if (ether_addr_equal(node->macaddress_A, ethhdr->h_source)) {
273 if (hsr->proto_ops->update_san_info)
274 hsr->proto_ops->update_san_info(node, is_sup);
275 return node;
276 }
277 if (ether_addr_equal(node->macaddress_B, ethhdr->h_source)) {
278 if (hsr->proto_ops->update_san_info)
279 hsr->proto_ops->update_san_info(node, is_sup);
280 return node;
281 }
282 }
283
284 /* Check if required node is not in proxy nodes table */
285 list_for_each_entry_rcu(node, &hsr->proxy_node_db, mac_list) {
286 if (ether_addr_equal(node->macaddress_A, ethhdr->h_source)) {
287 if (hsr->proto_ops->update_san_info)
288 hsr->proto_ops->update_san_info(node, is_sup);
289 return node;
290 }
291 }
292
293 /* Everyone may create a node entry, connected node to a HSR/PRP
294 * device.
295 */
296 if (ethhdr->h_proto == htons(ETH_P_PRP) ||
297 ethhdr->h_proto == htons(ETH_P_HSR)) {
298 /* Check if skb contains hsr_ethhdr */
299 if (skb->mac_len < sizeof(struct hsr_ethhdr))
300 return NULL;
301 } else {
302 rct = skb_get_PRP_rct(skb);
303 if (!rct && rx_port != HSR_PT_MASTER)
304 san = true;
305 }
306
307 return hsr_add_node(hsr, node_db, ethhdr->h_source, san, rx_port);
308 }
309
hsr_seq_block_is_old(struct hsr_seq_block * block)310 static bool hsr_seq_block_is_old(struct hsr_seq_block *block)
311 {
312 unsigned long expiry = msecs_to_jiffies(HSR_ENTRY_FORGET_TIME);
313
314 return time_is_before_jiffies(block->time + expiry);
315 }
316
hsr_forget_seq_block(struct hsr_node * node,struct hsr_seq_block * block)317 static void hsr_forget_seq_block(struct hsr_node *node,
318 struct hsr_seq_block *block)
319 {
320 if (block->time)
321 xa_erase(&node->seq_blocks, block->block_idx);
322 block->time = 0;
323 }
324
325 /* Get the currently active sequence number block. If there is no block yet, or
326 * the existing one is expired, a new block is created. The idea is to maintain
327 * a "sparse bitmap" where a bitmap for the whole sequence number space is
328 * split into blocks and not all blocks exist all the time. The blocks can
329 * expire after time (in low traffic situations) or when they are replaced in
330 * the backing fixed size buffer (in high traffic situations).
331 */
hsr_get_seq_block(struct hsr_node * node,u16 block_idx)332 VISIBLE_IF_KUNIT struct hsr_seq_block *hsr_get_seq_block(struct hsr_node *node,
333 u16 block_idx)
334 {
335 struct hsr_seq_block *block, *res;
336 size_t block_sz;
337
338 block = xa_load(&node->seq_blocks, block_idx);
339
340 if (block && hsr_seq_block_is_old(block)) {
341 hsr_forget_seq_block(node, block);
342 block = NULL;
343 }
344
345 if (!block) {
346 block_sz = hsr_seq_block_size(node);
347 block = node->block_buf + node->next_block * block_sz;
348 hsr_forget_seq_block(node, block);
349
350 memset(block, 0, block_sz);
351 block->time = jiffies;
352 block->block_idx = block_idx;
353
354 res = xa_store(&node->seq_blocks, block_idx, block, GFP_ATOMIC);
355 if (xa_is_err(res)) {
356 block->time = 0;
357 return NULL;
358 }
359
360 node->next_block =
361 (node->next_block + 1) & (HSR_MAX_SEQ_BLOCKS - 1);
362 }
363
364 return block;
365 }
366 EXPORT_SYMBOL_IF_KUNIT(hsr_get_seq_block);
367
368 /* Use the Supervision frame's info about an eventual macaddress_B for merging
369 * nodes that has previously had their macaddress_B registered as a separate
370 * node.
371 */
hsr_handle_sup_frame(struct hsr_frame_info * frame)372 void hsr_handle_sup_frame(struct hsr_frame_info *frame)
373 {
374 struct hsr_node *node_curr = frame->node_src;
375 struct hsr_port *port_rcv = frame->port_rcv;
376 struct hsr_seq_block *src_blk, *merge_blk;
377 struct hsr_priv *hsr = port_rcv->hsr;
378 struct hsr_sup_tlv *hsr_sup_tlv;
379 struct hsr_sup_payload *hsr_sp;
380 struct hsr_node *node_real;
381 struct sk_buff *skb = NULL;
382 struct list_head *node_db;
383 struct ethhdr *ethhdr;
384 unsigned int total_pull_size = 0;
385 unsigned int pull_size = 0;
386 unsigned long idx;
387 int i;
388
389 /* Here either frame->skb_hsr or frame->skb_prp should be
390 * valid as supervision frame always will have protocol
391 * header info.
392 */
393 if (frame->skb_hsr)
394 skb = frame->skb_hsr;
395 else if (frame->skb_prp)
396 skb = frame->skb_prp;
397 else if (frame->skb_std)
398 skb = frame->skb_std;
399 if (!skb)
400 return;
401
402 /* Leave the ethernet header. */
403 pull_size = sizeof(struct ethhdr);
404 skb_pull(skb, pull_size);
405 total_pull_size += pull_size;
406
407 ethhdr = (struct ethhdr *)skb_mac_header(skb);
408
409 /* And leave the HSR tag. */
410 if (ethhdr->h_proto == htons(ETH_P_HSR)) {
411 pull_size = sizeof(struct hsr_tag);
412 skb_pull(skb, pull_size);
413 total_pull_size += pull_size;
414 }
415
416 /* And leave the HSR sup tag. */
417 pull_size = sizeof(struct hsr_sup_tag);
418 skb_pull(skb, pull_size);
419 total_pull_size += pull_size;
420
421 /* get HSR sup payload */
422 hsr_sp = (struct hsr_sup_payload *)skb->data;
423
424 /* Merge node_curr (registered on macaddress_B) into node_real */
425 node_db = &port_rcv->hsr->node_db;
426 node_real = find_node_by_addr_A(node_db, hsr_sp->macaddress_A);
427 if (!node_real)
428 /* No frame received from AddrA of this node yet */
429 node_real = hsr_add_node(hsr, node_db, hsr_sp->macaddress_A,
430 true, port_rcv->type);
431 if (!node_real)
432 goto done; /* No mem */
433 if (node_real == node_curr)
434 /* Node has already been merged */
435 goto done;
436
437 /* Leave the first HSR sup payload. */
438 pull_size = sizeof(struct hsr_sup_payload);
439 skb_pull(skb, pull_size);
440 total_pull_size += pull_size;
441
442 /* Get second supervision tlv */
443 hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
444 /* And check if it is a redbox mac TLV */
445 if (hsr_sup_tlv->HSR_TLV_type == PRP_TLV_REDBOX_MAC) {
446 /* We could stop here after pushing hsr_sup_payload,
447 * or proceed and allow macaddress_B and for redboxes.
448 */
449 /* Sanity check length */
450 if (hsr_sup_tlv->HSR_TLV_length != 6)
451 goto done;
452
453 /* Leave the second HSR sup tlv. */
454 pull_size = sizeof(struct hsr_sup_tlv);
455 skb_pull(skb, pull_size);
456 total_pull_size += pull_size;
457
458 /* Get redbox mac address. */
459 hsr_sp = (struct hsr_sup_payload *)skb->data;
460
461 /* Check if redbox mac and node mac are equal. */
462 if (!ether_addr_equal(node_real->macaddress_A, hsr_sp->macaddress_A)) {
463 /* This is a redbox supervision frame for a VDAN! */
464 goto done;
465 }
466 }
467
468 ether_addr_copy(node_real->macaddress_B, ethhdr->h_source);
469 hsr_lock_seq_out_pair(node_real, node_curr);
470 for (i = 0; i < HSR_PT_PORTS; i++) {
471 if (!node_curr->time_in_stale[i] &&
472 time_after(node_curr->time_in[i], node_real->time_in[i])) {
473 node_real->time_in[i] = node_curr->time_in[i];
474 node_real->time_in_stale[i] =
475 node_curr->time_in_stale[i];
476 }
477 }
478
479 xa_for_each(&node_curr->seq_blocks, idx, src_blk) {
480 if (hsr_seq_block_is_old(src_blk))
481 continue;
482
483 merge_blk = hsr_get_seq_block(node_real, src_blk->block_idx);
484 if (!merge_blk)
485 continue;
486 merge_blk->time = min(merge_blk->time, src_blk->time);
487 for (i = 0; i < node_real->seq_port_cnt; i++) {
488 bitmap_or(merge_blk->seq_nrs[i], merge_blk->seq_nrs[i],
489 src_blk->seq_nrs[i], HSR_SEQ_BLOCK_SIZE);
490 }
491 }
492 hsr_unlock_seq_out_pair(node_real, node_curr);
493 node_real->addr_B_port = port_rcv->type;
494
495 spin_lock_bh(&hsr->list_lock);
496 if (!node_curr->removed) {
497 list_del_rcu(&node_curr->mac_list);
498 node_curr->removed = true;
499 call_rcu(&node_curr->rcu_head, hsr_free_node_rcu);
500 }
501 spin_unlock_bh(&hsr->list_lock);
502
503 done:
504 /* Push back here */
505 skb_push(skb, total_pull_size);
506 }
507
508 /* 'skb' is a frame meant for this host, that is to be passed to upper layers.
509 *
510 * If the frame was sent by a node's B interface, replace the source
511 * address with that node's "official" address (macaddress_A) so that upper
512 * layers recognize where it came from.
513 */
hsr_addr_subst_source(struct hsr_node * node,struct sk_buff * skb)514 void hsr_addr_subst_source(struct hsr_node *node, struct sk_buff *skb)
515 {
516 if (!skb_mac_header_was_set(skb)) {
517 WARN_ONCE(1, "%s: Mac header not set\n", __func__);
518 return;
519 }
520
521 memcpy(ð_hdr(skb)->h_source, node->macaddress_A, ETH_ALEN);
522 }
523
524 /* 'skb' is a frame meant for another host.
525 * 'port' is the outgoing interface
526 *
527 * Substitute the target (dest) MAC address if necessary, so the it matches the
528 * recipient interface MAC address, regardless of whether that is the
529 * recipient's A or B interface.
530 * This is needed to keep the packets flowing through switches that learn on
531 * which "side" the different interfaces are.
532 */
hsr_addr_subst_dest(struct hsr_node * node_src,struct sk_buff * skb,struct hsr_port * port)533 void hsr_addr_subst_dest(struct hsr_node *node_src, struct sk_buff *skb,
534 struct hsr_port *port)
535 {
536 struct hsr_node *node_dst;
537
538 if (!skb_mac_header_was_set(skb)) {
539 WARN_ONCE(1, "%s: Mac header not set\n", __func__);
540 return;
541 }
542
543 if (!is_unicast_ether_addr(eth_hdr(skb)->h_dest))
544 return;
545
546 node_dst = find_node_by_addr_A(&port->hsr->node_db,
547 eth_hdr(skb)->h_dest);
548 if (!node_dst && port->hsr->redbox)
549 node_dst = find_node_by_addr_A(&port->hsr->proxy_node_db,
550 eth_hdr(skb)->h_dest);
551
552 if (!node_dst) {
553 if (port->hsr->prot_version != PRP_V1 && net_ratelimit())
554 netdev_err(skb->dev, "%s: Unknown node\n", __func__);
555 return;
556 }
557 if (port->type != node_dst->addr_B_port)
558 return;
559
560 if (is_valid_ether_addr(node_dst->macaddress_B))
561 ether_addr_copy(eth_hdr(skb)->h_dest, node_dst->macaddress_B);
562 }
563
hsr_register_frame_in(struct hsr_node * node,struct hsr_port * port,u16 sequence_nr)564 void hsr_register_frame_in(struct hsr_node *node, struct hsr_port *port,
565 u16 sequence_nr)
566 {
567 node->time_in[port->type] = jiffies;
568 node->time_in_stale[port->type] = false;
569 }
570
571 /* Duplicate discard algorithm: we maintain a bitmap where we set a bit for
572 * every seen sequence number. The bitmap is split into blocks and the block
573 * management is detailed in hsr_get_seq_block(). In any case, we err on the
574 * side of accepting a packet, as the specification requires the algorithm to
575 * be "designed such that it never rejects a legitimate frame, while occasional
576 * acceptance of a duplicate can be tolerated." (IEC 62439-3:2021, 4.1.10.3).
577 * While this requirement is explicit for PRP, applying it to HSR does no harm
578 * either.
579 *
580 * 'frame' is the frame to be sent
581 * 'port_type' is the type of the outgoing interface
582 *
583 * Return:
584 * 1 if frame can be shown to have been sent recently on this interface,
585 * 0 otherwise
586 */
hsr_check_duplicate(struct hsr_frame_info * frame,unsigned int port_type)587 static int hsr_check_duplicate(struct hsr_frame_info *frame,
588 unsigned int port_type)
589 {
590 u16 sequence_nr, seq_bit, block_idx;
591 struct hsr_seq_block *block;
592 struct hsr_node *node;
593
594 node = frame->node_src;
595 sequence_nr = frame->sequence_nr;
596
597 if (WARN_ON_ONCE(port_type >= node->seq_port_cnt))
598 return 0;
599
600 spin_lock_bh(&node->seq_out_lock);
601
602 block_idx = hsr_seq_block_index(sequence_nr);
603 block = hsr_get_seq_block(node, block_idx);
604 if (!block)
605 goto out_new;
606
607 seq_bit = hsr_seq_block_bit(sequence_nr);
608 if (__test_and_set_bit(seq_bit, block->seq_nrs[port_type]))
609 goto out_seen;
610
611 out_new:
612 spin_unlock_bh(&node->seq_out_lock);
613 return 0;
614
615 out_seen:
616 spin_unlock_bh(&node->seq_out_lock);
617 return 1;
618 }
619
620 /* HSR duplicate discard: we check if the same frame has already been sent on
621 * this outgoing interface. The check follows the general duplicate discard
622 * algorithm.
623 *
624 * 'port' is the outgoing interface
625 * 'frame' is the frame to be sent
626 *
627 * Return:
628 * 1 if frame can be shown to have been sent recently on this interface,
629 * 0 otherwise
630 */
hsr_register_frame_out(struct hsr_port * port,struct hsr_frame_info * frame)631 int hsr_register_frame_out(struct hsr_port *port, struct hsr_frame_info *frame)
632 {
633 return hsr_check_duplicate(frame, port->type - 1);
634 }
635
636 /* PRP duplicate discard: we only consider frames that are received on port A
637 * or port B and should go to the master port. For those, we check if they have
638 * already been received by the host, i.e., master port. The check uses the
639 * general duplicate discard algorithm, but without tracking multiple ports.
640 *
641 * 'port' is the outgoing interface
642 * 'frame' is the frame to be sent
643 *
644 * Return:
645 * 1 if frame can be shown to have been sent recently on this interface,
646 * 0 otherwise
647 */
prp_register_frame_out(struct hsr_port * port,struct hsr_frame_info * frame)648 int prp_register_frame_out(struct hsr_port *port, struct hsr_frame_info *frame)
649 {
650 /* out-going frames are always in order */
651 if (frame->port_rcv->type == HSR_PT_MASTER)
652 return 0;
653
654 /* for PRP we should only forward frames from the slave ports
655 * to the master port
656 */
657 if (port->type != HSR_PT_MASTER)
658 return 1;
659
660 return hsr_check_duplicate(frame, 0);
661 }
662 EXPORT_SYMBOL_IF_KUNIT(prp_register_frame_out);
663
get_late_port(struct hsr_priv * hsr,struct hsr_node * node)664 static struct hsr_port *get_late_port(struct hsr_priv *hsr,
665 struct hsr_node *node)
666 {
667 if (node->time_in_stale[HSR_PT_SLAVE_A])
668 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
669 if (node->time_in_stale[HSR_PT_SLAVE_B])
670 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
671
672 if (time_after(node->time_in[HSR_PT_SLAVE_B],
673 node->time_in[HSR_PT_SLAVE_A] +
674 msecs_to_jiffies(MAX_SLAVE_DIFF)))
675 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
676 if (time_after(node->time_in[HSR_PT_SLAVE_A],
677 node->time_in[HSR_PT_SLAVE_B] +
678 msecs_to_jiffies(MAX_SLAVE_DIFF)))
679 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
680
681 return NULL;
682 }
683
684 /* Remove stale sequence_nr records. Called by timer every
685 * HSR_LIFE_CHECK_INTERVAL (two seconds or so).
686 */
hsr_prune_nodes(struct timer_list * t)687 void hsr_prune_nodes(struct timer_list *t)
688 {
689 struct hsr_priv *hsr = timer_container_of(hsr, t, prune_timer);
690 struct hsr_node *node;
691 struct hsr_node *tmp;
692 struct hsr_port *port;
693 unsigned long timestamp;
694 unsigned long time_a, time_b;
695
696 spin_lock_bh(&hsr->list_lock);
697 list_for_each_entry_safe(node, tmp, &hsr->node_db, mac_list) {
698 /* Don't prune own node. Neither time_in[HSR_PT_SLAVE_A]
699 * nor time_in[HSR_PT_SLAVE_B], will ever be updated for
700 * the master port. Thus the master node will be repeatedly
701 * pruned leading to packet loss.
702 */
703 if (hsr_addr_is_self(hsr, node->macaddress_A))
704 continue;
705
706 /* Shorthand */
707 time_a = node->time_in[HSR_PT_SLAVE_A];
708 time_b = node->time_in[HSR_PT_SLAVE_B];
709
710 /* Check for timestamps old enough to risk wrap-around */
711 if (time_after(jiffies, time_a + MAX_JIFFY_OFFSET / 2))
712 node->time_in_stale[HSR_PT_SLAVE_A] = true;
713 if (time_after(jiffies, time_b + MAX_JIFFY_OFFSET / 2))
714 node->time_in_stale[HSR_PT_SLAVE_B] = true;
715
716 /* Get age of newest frame from node.
717 * At least one time_in is OK here; nodes get pruned long
718 * before both time_ins can get stale
719 */
720 timestamp = time_a;
721 if (node->time_in_stale[HSR_PT_SLAVE_A] ||
722 (!node->time_in_stale[HSR_PT_SLAVE_B] &&
723 time_after(time_b, time_a)))
724 timestamp = time_b;
725
726 /* Warn of ring error only as long as we get frames at all */
727 if (time_is_after_jiffies(timestamp +
728 msecs_to_jiffies(1.5 * MAX_SLAVE_DIFF))) {
729 rcu_read_lock();
730 port = get_late_port(hsr, node);
731 if (port)
732 hsr_nl_ringerror(hsr, node->macaddress_A, port);
733 rcu_read_unlock();
734 }
735
736 /* Prune old entries */
737 if (time_is_before_jiffies(timestamp +
738 msecs_to_jiffies(HSR_NODE_FORGET_TIME))) {
739 hsr_nl_nodedown(hsr, node->macaddress_A);
740 if (!node->removed) {
741 list_del_rcu(&node->mac_list);
742 node->removed = true;
743 /* Note that we need to free this entry later: */
744 call_rcu(&node->rcu_head, hsr_free_node_rcu);
745 }
746 }
747 }
748 spin_unlock_bh(&hsr->list_lock);
749
750 /* Restart timer */
751 mod_timer(&hsr->prune_timer,
752 jiffies + msecs_to_jiffies(PRUNE_PERIOD));
753 }
754
hsr_prune_proxy_nodes(struct timer_list * t)755 void hsr_prune_proxy_nodes(struct timer_list *t)
756 {
757 struct hsr_priv *hsr = timer_container_of(hsr, t, prune_proxy_timer);
758 unsigned long timestamp;
759 struct hsr_node *node;
760 struct hsr_node *tmp;
761
762 spin_lock_bh(&hsr->list_lock);
763 list_for_each_entry_safe(node, tmp, &hsr->proxy_node_db, mac_list) {
764 /* Don't prune RedBox node. */
765 if (hsr_addr_is_redbox(hsr, node->macaddress_A))
766 continue;
767
768 timestamp = node->time_in[HSR_PT_INTERLINK];
769
770 /* Prune old entries */
771 if (time_is_before_jiffies(timestamp +
772 msecs_to_jiffies(HSR_PROXY_NODE_FORGET_TIME))) {
773 hsr_nl_nodedown(hsr, node->macaddress_A);
774 if (!node->removed) {
775 list_del_rcu(&node->mac_list);
776 node->removed = true;
777 /* Note that we need to free this entry later: */
778 call_rcu(&node->rcu_head, hsr_free_node_rcu);
779 }
780 }
781 }
782
783 spin_unlock_bh(&hsr->list_lock);
784
785 /* Restart timer */
786 mod_timer(&hsr->prune_proxy_timer,
787 jiffies + msecs_to_jiffies(PRUNE_PROXY_PERIOD));
788 }
789
hsr_get_next_node(struct hsr_priv * hsr,void * _pos,unsigned char addr[ETH_ALEN])790 void *hsr_get_next_node(struct hsr_priv *hsr, void *_pos,
791 unsigned char addr[ETH_ALEN])
792 {
793 struct hsr_node *node;
794
795 if (!_pos) {
796 node = list_first_or_null_rcu(&hsr->node_db,
797 struct hsr_node, mac_list);
798 if (node)
799 ether_addr_copy(addr, node->macaddress_A);
800 return node;
801 }
802
803 node = _pos;
804 list_for_each_entry_continue_rcu(node, &hsr->node_db, mac_list) {
805 ether_addr_copy(addr, node->macaddress_A);
806 return node;
807 }
808
809 return NULL;
810 }
811
812 /* Fill the last sequence number that has been received from node on if1 by
813 * finding the last sequence number sent on port B; accordingly get the last
814 * received sequence number for if2 using sent sequence numbers on port A.
815 */
fill_last_seq_nrs(struct hsr_node * node,u16 * if1_seq,u16 * if2_seq)816 static void fill_last_seq_nrs(struct hsr_node *node, u16 *if1_seq, u16 *if2_seq)
817 {
818 struct hsr_seq_block *block;
819 unsigned int block_off;
820 size_t block_sz;
821 u16 seq_bit;
822
823 spin_lock_bh(&node->seq_out_lock);
824
825 /* Get last inserted block */
826 block_off = (node->next_block - 1) & (HSR_MAX_SEQ_BLOCKS - 1);
827 block_sz = hsr_seq_block_size(node);
828 block = node->block_buf + block_off * block_sz;
829
830 if (!bitmap_empty(block->seq_nrs[HSR_PT_SLAVE_B - 1],
831 HSR_SEQ_BLOCK_SIZE)) {
832 seq_bit = find_last_bit(block->seq_nrs[HSR_PT_SLAVE_B - 1],
833 HSR_SEQ_BLOCK_SIZE);
834 *if1_seq = (block->block_idx << HSR_SEQ_BLOCK_SHIFT) | seq_bit;
835 }
836 if (!bitmap_empty(block->seq_nrs[HSR_PT_SLAVE_A - 1],
837 HSR_SEQ_BLOCK_SIZE)) {
838 seq_bit = find_last_bit(block->seq_nrs[HSR_PT_SLAVE_A - 1],
839 HSR_SEQ_BLOCK_SIZE);
840 *if2_seq = (block->block_idx << HSR_SEQ_BLOCK_SHIFT) | seq_bit;
841 }
842 spin_unlock_bh(&node->seq_out_lock);
843 }
844
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)845 int hsr_get_node_data(struct hsr_priv *hsr,
846 const unsigned char *addr,
847 unsigned char addr_b[ETH_ALEN],
848 unsigned int *addr_b_ifindex,
849 int *if1_age,
850 u16 *if1_seq,
851 int *if2_age,
852 u16 *if2_seq)
853 {
854 struct hsr_node *node;
855 struct hsr_port *port;
856 unsigned long tdiff;
857
858 node = find_node_by_addr_A(&hsr->node_db, addr);
859 if (!node)
860 return -ENOENT;
861
862 ether_addr_copy(addr_b, node->macaddress_B);
863
864 tdiff = jiffies - node->time_in[HSR_PT_SLAVE_A];
865 if (node->time_in_stale[HSR_PT_SLAVE_A])
866 *if1_age = INT_MAX;
867 #if HZ <= MSEC_PER_SEC
868 else if (tdiff > msecs_to_jiffies(INT_MAX))
869 *if1_age = INT_MAX;
870 #endif
871 else
872 *if1_age = jiffies_to_msecs(tdiff);
873
874 tdiff = jiffies - node->time_in[HSR_PT_SLAVE_B];
875 if (node->time_in_stale[HSR_PT_SLAVE_B])
876 *if2_age = INT_MAX;
877 #if HZ <= MSEC_PER_SEC
878 else if (tdiff > msecs_to_jiffies(INT_MAX))
879 *if2_age = INT_MAX;
880 #endif
881 else
882 *if2_age = jiffies_to_msecs(tdiff);
883
884 /* Present sequence numbers as if they were incoming on interface */
885 *if1_seq = 0;
886 *if2_seq = 0;
887 if (hsr->prot_version != PRP_V1)
888 fill_last_seq_nrs(node, if1_seq, if2_seq);
889
890 if (node->addr_B_port != HSR_PT_NONE) {
891 port = hsr_port_get_hsr(hsr, node->addr_B_port);
892 *addr_b_ifindex = port->dev->ifindex;
893 } else {
894 *addr_b_ifindex = -1;
895 }
896
897 return 0;
898 }
899