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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 */
12
13#include <linux/if_ether.h>
14#include <linux/etherdevice.h>
15#include <linux/slab.h>
16#include <linux/rculist.h>
17#include "hsr_main.h"
18#include "hsr_framereg.h"
19#include "hsr_netlink.h"
20
21/* TODO: use hash lists for mac addresses (linux/jhash.h)? */
22
23/* seq_nr_after(a, b) - return true if a is after (higher in sequence than) b,
24 * false otherwise.
25 */
26static bool seq_nr_after(u16 a, u16 b)
27{
28 /* Remove inconsistency where
29 * seq_nr_after(a, b) == seq_nr_before(a, b)
30 */
31 if ((int)b - a == 32768)
32 return false;
33
34 return (((s16)(b - a)) < 0);
35}
36
37#define seq_nr_before(a, b) seq_nr_after((b), (a))
38#define seq_nr_after_or_eq(a, b) (!seq_nr_before((a), (b)))
39#define seq_nr_before_or_eq(a, b) (!seq_nr_after((a), (b)))
40
41bool hsr_addr_is_self(struct hsr_priv *hsr, unsigned char *addr)
42{
43 struct hsr_node *node;
44
45 node = list_first_or_null_rcu(&hsr->self_node_db, struct hsr_node,
46 mac_list);
47 if (!node) {
48 WARN_ONCE(1, "HSR: No self node\n");
49 return false;
50 }
51
52 if (ether_addr_equal(addr, node->macaddress_A))
53 return true;
54 if (ether_addr_equal(addr, node->macaddress_B))
55 return true;
56
57 return false;
58}
59
60/* Search for mac entry. Caller must hold rcu read lock.
61 */
62static struct hsr_node *find_node_by_addr_A(struct list_head *node_db,
63 const unsigned char addr[ETH_ALEN])
64{
65 struct hsr_node *node;
66
67 list_for_each_entry_rcu(node, node_db, mac_list) {
68 if (ether_addr_equal(node->macaddress_A, addr))
69 return node;
70 }
71
72 return NULL;
73}
74
75/* Helper for device init; the self_node_db is used in hsr_rcv() to recognize
76 * frames from self that's been looped over the HSR ring.
77 */
78int hsr_create_self_node(struct list_head *self_node_db,
79 unsigned char addr_a[ETH_ALEN],
80 unsigned char addr_b[ETH_ALEN])
81{
82 struct hsr_node *node, *oldnode;
83
84 node = kmalloc(sizeof(*node), GFP_KERNEL);
85 if (!node)
86 return -ENOMEM;
87
88 ether_addr_copy(node->macaddress_A, addr_a);
89 ether_addr_copy(node->macaddress_B, addr_b);
90
91 rcu_read_lock();
92 oldnode = list_first_or_null_rcu(self_node_db,
93 struct hsr_node, mac_list);
94 if (oldnode) {
95 list_replace_rcu(&oldnode->mac_list, &node->mac_list);
96 rcu_read_unlock();
97 synchronize_rcu();
98 kfree(oldnode);
99 } else {
100 rcu_read_unlock();
101 list_add_tail_rcu(&node->mac_list, self_node_db);
102 }
103
104 return 0;
105}
106
107void hsr_del_self_node(struct list_head *self_node_db)
108{
109 struct hsr_node *node;
110
111 rcu_read_lock();
112 node = list_first_or_null_rcu(self_node_db, struct hsr_node, mac_list);
113 rcu_read_unlock();
114 if (node) {
115 list_del_rcu(&node->mac_list);
116 kfree(node);
117 }
118}
119
120void hsr_del_nodes(struct list_head *node_db)
121{
122 struct hsr_node *node;
123 struct hsr_node *tmp;
124
125 list_for_each_entry_safe(node, tmp, node_db, mac_list)
126 kfree(node);
127}
128
129/* Allocate an hsr_node and add it to node_db. 'addr' is the node's address_A;
130 * seq_out is used to initialize filtering of outgoing duplicate frames
131 * originating from the newly added node.
132 */
133struct hsr_node *hsr_add_node(struct list_head *node_db, unsigned char addr[],
134 u16 seq_out)
135{
136 struct hsr_node *node;
137 unsigned long now;
138 int i;
139
140 node = kzalloc(sizeof(*node), GFP_ATOMIC);
141 if (!node)
142 return NULL;
143
144 ether_addr_copy(node->macaddress_A, addr);
145
146 /* We are only interested in time diffs here, so use current jiffies
147 * as initialization. (0 could trigger an spurious ring error warning).
148 */
149 now = jiffies;
150 for (i = 0; i < HSR_PT_PORTS; i++)
151 node->time_in[i] = now;
152 for (i = 0; i < HSR_PT_PORTS; i++)
153 node->seq_out[i] = seq_out;
154
155 list_add_tail_rcu(&node->mac_list, node_db);
156
157 return node;
158}
159
160/* Get the hsr_node from which 'skb' was sent.
161 */
162struct hsr_node *hsr_get_node(struct hsr_port *port, struct sk_buff *skb,
163 bool is_sup)
164{
165 struct list_head *node_db = &port->hsr->node_db;
166 struct hsr_node *node;
167 struct ethhdr *ethhdr;
168 u16 seq_out;
169
170 if (!skb_mac_header_was_set(skb))
171 return NULL;
172
173 ethhdr = (struct ethhdr *)skb_mac_header(skb);
174
175 list_for_each_entry_rcu(node, node_db, mac_list) {
176 if (ether_addr_equal(node->macaddress_A, ethhdr->h_source))
177 return node;
178 if (ether_addr_equal(node->macaddress_B, ethhdr->h_source))
179 return node;
180 }
181
182 /* Everyone may create a node entry, connected node to a HSR device. */
183
184 if (ethhdr->h_proto == htons(ETH_P_PRP) ||
185 ethhdr->h_proto == htons(ETH_P_HSR)) {
186 /* Use the existing sequence_nr from the tag as starting point
187 * for filtering duplicate frames.
188 */
189 seq_out = hsr_get_skb_sequence_nr(skb) - 1;
190 } else {
191 /* this is called also for frames from master port and
192 * so warn only for non master ports
193 */
194 if (port->type != HSR_PT_MASTER)
195 WARN_ONCE(1, "%s: Non-HSR frame\n", __func__);
196 seq_out = HSR_SEQNR_START;
197 }
198
199 return hsr_add_node(node_db, ethhdr->h_source, seq_out);
200}
201
202/* Use the Supervision frame's info about an eventual macaddress_B for merging
203 * nodes that has previously had their macaddress_B registered as a separate
204 * node.
205 */
206void hsr_handle_sup_frame(struct sk_buff *skb, struct hsr_node *node_curr,
207 struct hsr_port *port_rcv)
208{
209 struct ethhdr *ethhdr;
210 struct hsr_node *node_real;
211 struct hsr_sup_payload *hsr_sp;
212 struct list_head *node_db;
213 int i;
214
215 ethhdr = (struct ethhdr *)skb_mac_header(skb);
216
217 /* Leave the ethernet header. */
218 skb_pull(skb, sizeof(struct ethhdr));
219
220 /* And leave the HSR tag. */
221 if (ethhdr->h_proto == htons(ETH_P_HSR))
222 skb_pull(skb, sizeof(struct hsr_tag));
223
224 /* And leave the HSR sup tag. */
225 skb_pull(skb, sizeof(struct hsr_sup_tag));
226
227 hsr_sp = (struct hsr_sup_payload *)skb->data;
228
229 /* Merge node_curr (registered on macaddress_B) into node_real */
230 node_db = &port_rcv->hsr->node_db;
231 node_real = find_node_by_addr_A(node_db, hsr_sp->macaddress_A);
232 if (!node_real)
233 /* No frame received from AddrA of this node yet */
234 node_real = hsr_add_node(node_db, hsr_sp->macaddress_A,
235 HSR_SEQNR_START - 1);
236 if (!node_real)
237 goto done; /* No mem */
238 if (node_real == node_curr)
239 /* Node has already been merged */
240 goto done;
241
242 ether_addr_copy(node_real->macaddress_B, ethhdr->h_source);
243 for (i = 0; i < HSR_PT_PORTS; i++) {
244 if (!node_curr->time_in_stale[i] &&
245 time_after(node_curr->time_in[i], node_real->time_in[i])) {
246 node_real->time_in[i] = node_curr->time_in[i];
247 node_real->time_in_stale[i] =
248 node_curr->time_in_stale[i];
249 }
250 if (seq_nr_after(node_curr->seq_out[i], node_real->seq_out[i]))
251 node_real->seq_out[i] = node_curr->seq_out[i];
252 }
253 node_real->addr_B_port = port_rcv->type;
254
255 list_del_rcu(&node_curr->mac_list);
256 kfree_rcu(node_curr, rcu_head);
257
258done:
259 skb_push(skb, sizeof(struct hsrv1_ethhdr_sp));
260}
261
262/* 'skb' is a frame meant for this host, that is to be passed to upper layers.
263 *
264 * If the frame was sent by a node's B interface, replace the source
265 * address with that node's "official" address (macaddress_A) so that upper
266 * layers recognize where it came from.
267 */
268void hsr_addr_subst_source(struct hsr_node *node, struct sk_buff *skb)
269{
270 if (!skb_mac_header_was_set(skb)) {
271 WARN_ONCE(1, "%s: Mac header not set\n", __func__);
272 return;
273 }
274
275 memcpy(ð_hdr(skb)->h_source, node->macaddress_A, ETH_ALEN);
276}
277
278/* 'skb' is a frame meant for another host.
279 * 'port' is the outgoing interface
280 *
281 * Substitute the target (dest) MAC address if necessary, so the it matches the
282 * recipient interface MAC address, regardless of whether that is the
283 * recipient's A or B interface.
284 * This is needed to keep the packets flowing through switches that learn on
285 * which "side" the different interfaces are.
286 */
287void hsr_addr_subst_dest(struct hsr_node *node_src, struct sk_buff *skb,
288 struct hsr_port *port)
289{
290 struct hsr_node *node_dst;
291
292 if (!skb_mac_header_was_set(skb)) {
293 WARN_ONCE(1, "%s: Mac header not set\n", __func__);
294 return;
295 }
296
297 if (!is_unicast_ether_addr(eth_hdr(skb)->h_dest))
298 return;
299
300 node_dst = find_node_by_addr_A(&port->hsr->node_db,
301 eth_hdr(skb)->h_dest);
302 if (!node_dst) {
303 WARN_ONCE(1, "%s: Unknown node\n", __func__);
304 return;
305 }
306 if (port->type != node_dst->addr_B_port)
307 return;
308
309 ether_addr_copy(eth_hdr(skb)->h_dest, node_dst->macaddress_B);
310}
311
312void hsr_register_frame_in(struct hsr_node *node, struct hsr_port *port,
313 u16 sequence_nr)
314{
315 /* Don't register incoming frames without a valid sequence number. This
316 * ensures entries of restarted nodes gets pruned so that they can
317 * re-register and resume communications.
318 */
319 if (seq_nr_before(sequence_nr, node->seq_out[port->type]))
320 return;
321
322 node->time_in[port->type] = jiffies;
323 node->time_in_stale[port->type] = false;
324}
325
326/* 'skb' is a HSR Ethernet frame (with a HSR tag inserted), with a valid
327 * ethhdr->h_source address and skb->mac_header set.
328 *
329 * Return:
330 * 1 if frame can be shown to have been sent recently on this interface,
331 * 0 otherwise, or
332 * negative error code on error
333 */
334int hsr_register_frame_out(struct hsr_port *port, struct hsr_node *node,
335 u16 sequence_nr)
336{
337 if (seq_nr_before_or_eq(sequence_nr, node->seq_out[port->type]))
338 return 1;
339
340 node->seq_out[port->type] = sequence_nr;
341 return 0;
342}
343
344static struct hsr_port *get_late_port(struct hsr_priv *hsr,
345 struct hsr_node *node)
346{
347 if (node->time_in_stale[HSR_PT_SLAVE_A])
348 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
349 if (node->time_in_stale[HSR_PT_SLAVE_B])
350 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
351
352 if (time_after(node->time_in[HSR_PT_SLAVE_B],
353 node->time_in[HSR_PT_SLAVE_A] +
354 msecs_to_jiffies(MAX_SLAVE_DIFF)))
355 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
356 if (time_after(node->time_in[HSR_PT_SLAVE_A],
357 node->time_in[HSR_PT_SLAVE_B] +
358 msecs_to_jiffies(MAX_SLAVE_DIFF)))
359 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
360
361 return NULL;
362}
363
364/* Remove stale sequence_nr records. Called by timer every
365 * HSR_LIFE_CHECK_INTERVAL (two seconds or so).
366 */
367void hsr_prune_nodes(struct timer_list *t)
368{
369 struct hsr_priv *hsr = from_timer(hsr, t, prune_timer);
370 struct hsr_node *node;
371 struct hsr_port *port;
372 unsigned long timestamp;
373 unsigned long time_a, time_b;
374
375 rcu_read_lock();
376 list_for_each_entry_rcu(node, &hsr->node_db, mac_list) {
377 /* Don't prune own node. Neither time_in[HSR_PT_SLAVE_A]
378 * nor time_in[HSR_PT_SLAVE_B], will ever be updated for
379 * the master port. Thus the master node will be repeatedly
380 * pruned leading to packet loss.
381 */
382 if (hsr_addr_is_self(hsr, node->macaddress_A))
383 continue;
384
385 /* Shorthand */
386 time_a = node->time_in[HSR_PT_SLAVE_A];
387 time_b = node->time_in[HSR_PT_SLAVE_B];
388
389 /* Check for timestamps old enough to risk wrap-around */
390 if (time_after(jiffies, time_a + MAX_JIFFY_OFFSET / 2))
391 node->time_in_stale[HSR_PT_SLAVE_A] = true;
392 if (time_after(jiffies, time_b + MAX_JIFFY_OFFSET / 2))
393 node->time_in_stale[HSR_PT_SLAVE_B] = true;
394
395 /* Get age of newest frame from node.
396 * At least one time_in is OK here; nodes get pruned long
397 * before both time_ins can get stale
398 */
399 timestamp = time_a;
400 if (node->time_in_stale[HSR_PT_SLAVE_A] ||
401 (!node->time_in_stale[HSR_PT_SLAVE_B] &&
402 time_after(time_b, time_a)))
403 timestamp = time_b;
404
405 /* Warn of ring error only as long as we get frames at all */
406 if (time_is_after_jiffies(timestamp +
407 msecs_to_jiffies(1.5 * MAX_SLAVE_DIFF))) {
408 rcu_read_lock();
409 port = get_late_port(hsr, node);
410 if (port)
411 hsr_nl_ringerror(hsr, node->macaddress_A, port);
412 rcu_read_unlock();
413 }
414
415 /* Prune old entries */
416 if (time_is_before_jiffies(timestamp +
417 msecs_to_jiffies(HSR_NODE_FORGET_TIME))) {
418 hsr_nl_nodedown(hsr, node->macaddress_A);
419 list_del_rcu(&node->mac_list);
420 /* Note that we need to free this entry later: */
421 kfree_rcu(node, rcu_head);
422 }
423 }
424 rcu_read_unlock();
425
426 /* Restart timer */
427 mod_timer(&hsr->prune_timer,
428 jiffies + msecs_to_jiffies(PRUNE_PERIOD));
429}
430
431void *hsr_get_next_node(struct hsr_priv *hsr, void *_pos,
432 unsigned char addr[ETH_ALEN])
433{
434 struct hsr_node *node;
435
436 if (!_pos) {
437 node = list_first_or_null_rcu(&hsr->node_db,
438 struct hsr_node, mac_list);
439 if (node)
440 ether_addr_copy(addr, node->macaddress_A);
441 return node;
442 }
443
444 node = _pos;
445 list_for_each_entry_continue_rcu(node, &hsr->node_db, mac_list) {
446 ether_addr_copy(addr, node->macaddress_A);
447 return node;
448 }
449
450 return NULL;
451}
452
453int hsr_get_node_data(struct hsr_priv *hsr,
454 const unsigned char *addr,
455 unsigned char addr_b[ETH_ALEN],
456 unsigned int *addr_b_ifindex,
457 int *if1_age,
458 u16 *if1_seq,
459 int *if2_age,
460 u16 *if2_seq)
461{
462 struct hsr_node *node;
463 struct hsr_port *port;
464 unsigned long tdiff;
465
466 rcu_read_lock();
467 node = find_node_by_addr_A(&hsr->node_db, addr);
468 if (!node) {
469 rcu_read_unlock();
470 return -ENOENT; /* No such entry */
471 }
472
473 ether_addr_copy(addr_b, node->macaddress_B);
474
475 tdiff = jiffies - node->time_in[HSR_PT_SLAVE_A];
476 if (node->time_in_stale[HSR_PT_SLAVE_A])
477 *if1_age = INT_MAX;
478#if HZ <= MSEC_PER_SEC
479 else if (tdiff > msecs_to_jiffies(INT_MAX))
480 *if1_age = INT_MAX;
481#endif
482 else
483 *if1_age = jiffies_to_msecs(tdiff);
484
485 tdiff = jiffies - node->time_in[HSR_PT_SLAVE_B];
486 if (node->time_in_stale[HSR_PT_SLAVE_B])
487 *if2_age = INT_MAX;
488#if HZ <= MSEC_PER_SEC
489 else if (tdiff > msecs_to_jiffies(INT_MAX))
490 *if2_age = INT_MAX;
491#endif
492 else
493 *if2_age = jiffies_to_msecs(tdiff);
494
495 /* Present sequence numbers as if they were incoming on interface */
496 *if1_seq = node->seq_out[HSR_PT_SLAVE_B];
497 *if2_seq = node->seq_out[HSR_PT_SLAVE_A];
498
499 if (node->addr_B_port != HSR_PT_NONE) {
500 port = hsr_port_get_hsr(hsr, node->addr_B_port);
501 *addr_b_ifindex = port->dev->ifindex;
502 } else {
503 *addr_b_ifindex = -1;
504 }
505
506 rcu_read_unlock();
507
508 return 0;
509}
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 */
25static 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
39bool hsr_addr_is_self(struct hsr_priv *hsr, unsigned char *addr)
40{
41 struct hsr_self_node *sn;
42 bool ret = false;
43
44 rcu_read_lock();
45 sn = rcu_dereference(hsr->self_node);
46 if (!sn) {
47 WARN_ONCE(1, "HSR: No self node\n");
48 goto out;
49 }
50
51 if (ether_addr_equal(addr, sn->macaddress_A) ||
52 ether_addr_equal(addr, sn->macaddress_B))
53 ret = true;
54out:
55 rcu_read_unlock();
56 return ret;
57}
58
59/* Search for mac entry. Caller must hold rcu read lock.
60 */
61static struct hsr_node *find_node_by_addr_A(struct list_head *node_db,
62 const unsigned char addr[ETH_ALEN])
63{
64 struct hsr_node *node;
65
66 list_for_each_entry_rcu(node, node_db, mac_list) {
67 if (ether_addr_equal(node->macaddress_A, addr))
68 return node;
69 }
70
71 return NULL;
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 */
77int 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(sizeof(*sn), GFP_KERNEL);
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
100void 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
112void hsr_del_nodes(struct list_head *node_db)
113{
114 struct hsr_node *node;
115 struct hsr_node *tmp;
116
117 list_for_each_entry_safe(node, tmp, node_db, mac_list)
118 kfree(node);
119}
120
121void prp_handle_san_frame(bool san, enum hsr_port_type port,
122 struct hsr_node *node)
123{
124 /* Mark if the SAN node is over LAN_A or LAN_B */
125 if (port == HSR_PT_SLAVE_A) {
126 node->san_a = true;
127 return;
128 }
129
130 if (port == HSR_PT_SLAVE_B)
131 node->san_b = true;
132}
133
134/* Allocate an hsr_node and add it to node_db. 'addr' is the node's address_A;
135 * seq_out is used to initialize filtering of outgoing duplicate frames
136 * originating from the newly added node.
137 */
138static struct hsr_node *hsr_add_node(struct hsr_priv *hsr,
139 struct list_head *node_db,
140 unsigned char addr[],
141 u16 seq_out, bool san,
142 enum hsr_port_type rx_port)
143{
144 struct hsr_node *new_node, *node;
145 unsigned long now;
146 int i;
147
148 new_node = kzalloc(sizeof(*new_node), GFP_ATOMIC);
149 if (!new_node)
150 return NULL;
151
152 ether_addr_copy(new_node->macaddress_A, addr);
153 spin_lock_init(&new_node->seq_out_lock);
154
155 /* We are only interested in time diffs here, so use current jiffies
156 * as initialization. (0 could trigger an spurious ring error warning).
157 */
158 now = jiffies;
159 for (i = 0; i < HSR_PT_PORTS; i++) {
160 new_node->time_in[i] = now;
161 new_node->time_out[i] = now;
162 }
163 for (i = 0; i < HSR_PT_PORTS; i++)
164 new_node->seq_out[i] = seq_out;
165
166 if (san && hsr->proto_ops->handle_san_frame)
167 hsr->proto_ops->handle_san_frame(san, rx_port, new_node);
168
169 spin_lock_bh(&hsr->list_lock);
170 list_for_each_entry_rcu(node, node_db, mac_list,
171 lockdep_is_held(&hsr->list_lock)) {
172 if (ether_addr_equal(node->macaddress_A, addr))
173 goto out;
174 if (ether_addr_equal(node->macaddress_B, addr))
175 goto out;
176 }
177 list_add_tail_rcu(&new_node->mac_list, node_db);
178 spin_unlock_bh(&hsr->list_lock);
179 return new_node;
180out:
181 spin_unlock_bh(&hsr->list_lock);
182 kfree(new_node);
183 return node;
184}
185
186void prp_update_san_info(struct hsr_node *node, bool is_sup)
187{
188 if (!is_sup)
189 return;
190
191 node->san_a = false;
192 node->san_b = false;
193}
194
195/* Get the hsr_node from which 'skb' was sent.
196 */
197struct hsr_node *hsr_get_node(struct hsr_port *port, struct list_head *node_db,
198 struct sk_buff *skb, bool is_sup,
199 enum hsr_port_type rx_port)
200{
201 struct hsr_priv *hsr = port->hsr;
202 struct hsr_node *node;
203 struct ethhdr *ethhdr;
204 struct prp_rct *rct;
205 bool san = false;
206 u16 seq_out;
207
208 if (!skb_mac_header_was_set(skb))
209 return NULL;
210
211 ethhdr = (struct ethhdr *)skb_mac_header(skb);
212
213 list_for_each_entry_rcu(node, node_db, mac_list) {
214 if (ether_addr_equal(node->macaddress_A, ethhdr->h_source)) {
215 if (hsr->proto_ops->update_san_info)
216 hsr->proto_ops->update_san_info(node, is_sup);
217 return node;
218 }
219 if (ether_addr_equal(node->macaddress_B, ethhdr->h_source)) {
220 if (hsr->proto_ops->update_san_info)
221 hsr->proto_ops->update_san_info(node, is_sup);
222 return node;
223 }
224 }
225
226 /* Everyone may create a node entry, connected node to a HSR/PRP
227 * device.
228 */
229 if (ethhdr->h_proto == htons(ETH_P_PRP) ||
230 ethhdr->h_proto == htons(ETH_P_HSR)) {
231 /* Use the existing sequence_nr from the tag as starting point
232 * for filtering duplicate frames.
233 */
234 seq_out = hsr_get_skb_sequence_nr(skb) - 1;
235 } else {
236 rct = skb_get_PRP_rct(skb);
237 if (rct && prp_check_lsdu_size(skb, rct, is_sup)) {
238 seq_out = prp_get_skb_sequence_nr(rct);
239 } else {
240 if (rx_port != HSR_PT_MASTER)
241 san = true;
242 seq_out = HSR_SEQNR_START;
243 }
244 }
245
246 return hsr_add_node(hsr, node_db, ethhdr->h_source, seq_out,
247 san, rx_port);
248}
249
250/* Use the Supervision frame's info about an eventual macaddress_B for merging
251 * nodes that has previously had their macaddress_B registered as a separate
252 * node.
253 */
254void hsr_handle_sup_frame(struct hsr_frame_info *frame)
255{
256 struct hsr_node *node_curr = frame->node_src;
257 struct hsr_port *port_rcv = frame->port_rcv;
258 struct hsr_priv *hsr = port_rcv->hsr;
259 struct hsr_sup_payload *hsr_sp;
260 struct hsr_sup_tlv *hsr_sup_tlv;
261 struct hsr_node *node_real;
262 struct sk_buff *skb = NULL;
263 struct list_head *node_db;
264 struct ethhdr *ethhdr;
265 int i;
266 unsigned int pull_size = 0;
267 unsigned int total_pull_size = 0;
268
269 /* Here either frame->skb_hsr or frame->skb_prp should be
270 * valid as supervision frame always will have protocol
271 * header info.
272 */
273 if (frame->skb_hsr)
274 skb = frame->skb_hsr;
275 else if (frame->skb_prp)
276 skb = frame->skb_prp;
277 else if (frame->skb_std)
278 skb = frame->skb_std;
279 if (!skb)
280 return;
281
282 /* Leave the ethernet header. */
283 pull_size = sizeof(struct ethhdr);
284 skb_pull(skb, pull_size);
285 total_pull_size += pull_size;
286
287 ethhdr = (struct ethhdr *)skb_mac_header(skb);
288
289 /* And leave the HSR tag. */
290 if (ethhdr->h_proto == htons(ETH_P_HSR)) {
291 pull_size = sizeof(struct hsr_tag);
292 skb_pull(skb, pull_size);
293 total_pull_size += pull_size;
294 }
295
296 /* And leave the HSR sup tag. */
297 pull_size = sizeof(struct hsr_sup_tag);
298 skb_pull(skb, pull_size);
299 total_pull_size += pull_size;
300
301 /* get HSR sup payload */
302 hsr_sp = (struct hsr_sup_payload *)skb->data;
303
304 /* Merge node_curr (registered on macaddress_B) into node_real */
305 node_db = &port_rcv->hsr->node_db;
306 node_real = find_node_by_addr_A(node_db, hsr_sp->macaddress_A);
307 if (!node_real)
308 /* No frame received from AddrA of this node yet */
309 node_real = hsr_add_node(hsr, node_db, hsr_sp->macaddress_A,
310 HSR_SEQNR_START - 1, true,
311 port_rcv->type);
312 if (!node_real)
313 goto done; /* No mem */
314 if (node_real == node_curr)
315 /* Node has already been merged */
316 goto done;
317
318 /* Leave the first HSR sup payload. */
319 pull_size = sizeof(struct hsr_sup_payload);
320 skb_pull(skb, pull_size);
321 total_pull_size += pull_size;
322
323 /* Get second supervision tlv */
324 hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
325 /* And check if it is a redbox mac TLV */
326 if (hsr_sup_tlv->HSR_TLV_type == PRP_TLV_REDBOX_MAC) {
327 /* We could stop here after pushing hsr_sup_payload,
328 * or proceed and allow macaddress_B and for redboxes.
329 */
330 /* Sanity check length */
331 if (hsr_sup_tlv->HSR_TLV_length != 6)
332 goto done;
333
334 /* Leave the second HSR sup tlv. */
335 pull_size = sizeof(struct hsr_sup_tlv);
336 skb_pull(skb, pull_size);
337 total_pull_size += pull_size;
338
339 /* Get redbox mac address. */
340 hsr_sp = (struct hsr_sup_payload *)skb->data;
341
342 /* Check if redbox mac and node mac are equal. */
343 if (!ether_addr_equal(node_real->macaddress_A, hsr_sp->macaddress_A)) {
344 /* This is a redbox supervision frame for a VDAN! */
345 goto done;
346 }
347 }
348
349 ether_addr_copy(node_real->macaddress_B, ethhdr->h_source);
350 spin_lock_bh(&node_real->seq_out_lock);
351 for (i = 0; i < HSR_PT_PORTS; i++) {
352 if (!node_curr->time_in_stale[i] &&
353 time_after(node_curr->time_in[i], node_real->time_in[i])) {
354 node_real->time_in[i] = node_curr->time_in[i];
355 node_real->time_in_stale[i] =
356 node_curr->time_in_stale[i];
357 }
358 if (seq_nr_after(node_curr->seq_out[i], node_real->seq_out[i]))
359 node_real->seq_out[i] = node_curr->seq_out[i];
360 }
361 spin_unlock_bh(&node_real->seq_out_lock);
362 node_real->addr_B_port = port_rcv->type;
363
364 spin_lock_bh(&hsr->list_lock);
365 if (!node_curr->removed) {
366 list_del_rcu(&node_curr->mac_list);
367 node_curr->removed = true;
368 kfree_rcu(node_curr, rcu_head);
369 }
370 spin_unlock_bh(&hsr->list_lock);
371
372done:
373 /* Push back here */
374 skb_push(skb, total_pull_size);
375}
376
377/* 'skb' is a frame meant for this host, that is to be passed to upper layers.
378 *
379 * If the frame was sent by a node's B interface, replace the source
380 * address with that node's "official" address (macaddress_A) so that upper
381 * layers recognize where it came from.
382 */
383void hsr_addr_subst_source(struct hsr_node *node, struct sk_buff *skb)
384{
385 if (!skb_mac_header_was_set(skb)) {
386 WARN_ONCE(1, "%s: Mac header not set\n", __func__);
387 return;
388 }
389
390 memcpy(ð_hdr(skb)->h_source, node->macaddress_A, ETH_ALEN);
391}
392
393/* 'skb' is a frame meant for another host.
394 * 'port' is the outgoing interface
395 *
396 * Substitute the target (dest) MAC address if necessary, so the it matches the
397 * recipient interface MAC address, regardless of whether that is the
398 * recipient's A or B interface.
399 * This is needed to keep the packets flowing through switches that learn on
400 * which "side" the different interfaces are.
401 */
402void hsr_addr_subst_dest(struct hsr_node *node_src, struct sk_buff *skb,
403 struct hsr_port *port)
404{
405 struct hsr_node *node_dst;
406
407 if (!skb_mac_header_was_set(skb)) {
408 WARN_ONCE(1, "%s: Mac header not set\n", __func__);
409 return;
410 }
411
412 if (!is_unicast_ether_addr(eth_hdr(skb)->h_dest))
413 return;
414
415 node_dst = find_node_by_addr_A(&port->hsr->node_db,
416 eth_hdr(skb)->h_dest);
417 if (!node_dst) {
418 if (port->hsr->prot_version != PRP_V1 && net_ratelimit())
419 netdev_err(skb->dev, "%s: Unknown node\n", __func__);
420 return;
421 }
422 if (port->type != node_dst->addr_B_port)
423 return;
424
425 if (is_valid_ether_addr(node_dst->macaddress_B))
426 ether_addr_copy(eth_hdr(skb)->h_dest, node_dst->macaddress_B);
427}
428
429void hsr_register_frame_in(struct hsr_node *node, struct hsr_port *port,
430 u16 sequence_nr)
431{
432 /* Don't register incoming frames without a valid sequence number. This
433 * ensures entries of restarted nodes gets pruned so that they can
434 * re-register and resume communications.
435 */
436 if (!(port->dev->features & NETIF_F_HW_HSR_TAG_RM) &&
437 seq_nr_before(sequence_nr, node->seq_out[port->type]))
438 return;
439
440 node->time_in[port->type] = jiffies;
441 node->time_in_stale[port->type] = false;
442}
443
444/* 'skb' is a HSR Ethernet frame (with a HSR tag inserted), with a valid
445 * ethhdr->h_source address and skb->mac_header set.
446 *
447 * Return:
448 * 1 if frame can be shown to have been sent recently on this interface,
449 * 0 otherwise, or
450 * negative error code on error
451 */
452int hsr_register_frame_out(struct hsr_port *port, struct hsr_node *node,
453 u16 sequence_nr)
454{
455 spin_lock_bh(&node->seq_out_lock);
456 if (seq_nr_before_or_eq(sequence_nr, node->seq_out[port->type]) &&
457 time_is_after_jiffies(node->time_out[port->type] +
458 msecs_to_jiffies(HSR_ENTRY_FORGET_TIME))) {
459 spin_unlock_bh(&node->seq_out_lock);
460 return 1;
461 }
462
463 node->time_out[port->type] = jiffies;
464 node->seq_out[port->type] = sequence_nr;
465 spin_unlock_bh(&node->seq_out_lock);
466 return 0;
467}
468
469static struct hsr_port *get_late_port(struct hsr_priv *hsr,
470 struct hsr_node *node)
471{
472 if (node->time_in_stale[HSR_PT_SLAVE_A])
473 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
474 if (node->time_in_stale[HSR_PT_SLAVE_B])
475 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
476
477 if (time_after(node->time_in[HSR_PT_SLAVE_B],
478 node->time_in[HSR_PT_SLAVE_A] +
479 msecs_to_jiffies(MAX_SLAVE_DIFF)))
480 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
481 if (time_after(node->time_in[HSR_PT_SLAVE_A],
482 node->time_in[HSR_PT_SLAVE_B] +
483 msecs_to_jiffies(MAX_SLAVE_DIFF)))
484 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
485
486 return NULL;
487}
488
489/* Remove stale sequence_nr records. Called by timer every
490 * HSR_LIFE_CHECK_INTERVAL (two seconds or so).
491 */
492void hsr_prune_nodes(struct timer_list *t)
493{
494 struct hsr_priv *hsr = from_timer(hsr, t, prune_timer);
495 struct hsr_node *node;
496 struct hsr_node *tmp;
497 struct hsr_port *port;
498 unsigned long timestamp;
499 unsigned long time_a, time_b;
500
501 spin_lock_bh(&hsr->list_lock);
502 list_for_each_entry_safe(node, tmp, &hsr->node_db, mac_list) {
503 /* Don't prune own node. Neither time_in[HSR_PT_SLAVE_A]
504 * nor time_in[HSR_PT_SLAVE_B], will ever be updated for
505 * the master port. Thus the master node will be repeatedly
506 * pruned leading to packet loss.
507 */
508 if (hsr_addr_is_self(hsr, node->macaddress_A))
509 continue;
510
511 /* Shorthand */
512 time_a = node->time_in[HSR_PT_SLAVE_A];
513 time_b = node->time_in[HSR_PT_SLAVE_B];
514
515 /* Check for timestamps old enough to risk wrap-around */
516 if (time_after(jiffies, time_a + MAX_JIFFY_OFFSET / 2))
517 node->time_in_stale[HSR_PT_SLAVE_A] = true;
518 if (time_after(jiffies, time_b + MAX_JIFFY_OFFSET / 2))
519 node->time_in_stale[HSR_PT_SLAVE_B] = true;
520
521 /* Get age of newest frame from node.
522 * At least one time_in is OK here; nodes get pruned long
523 * before both time_ins can get stale
524 */
525 timestamp = time_a;
526 if (node->time_in_stale[HSR_PT_SLAVE_A] ||
527 (!node->time_in_stale[HSR_PT_SLAVE_B] &&
528 time_after(time_b, time_a)))
529 timestamp = time_b;
530
531 /* Warn of ring error only as long as we get frames at all */
532 if (time_is_after_jiffies(timestamp +
533 msecs_to_jiffies(1.5 * MAX_SLAVE_DIFF))) {
534 rcu_read_lock();
535 port = get_late_port(hsr, node);
536 if (port)
537 hsr_nl_ringerror(hsr, node->macaddress_A, port);
538 rcu_read_unlock();
539 }
540
541 /* Prune old entries */
542 if (time_is_before_jiffies(timestamp +
543 msecs_to_jiffies(HSR_NODE_FORGET_TIME))) {
544 hsr_nl_nodedown(hsr, node->macaddress_A);
545 if (!node->removed) {
546 list_del_rcu(&node->mac_list);
547 node->removed = true;
548 /* Note that we need to free this entry later: */
549 kfree_rcu(node, rcu_head);
550 }
551 }
552 }
553 spin_unlock_bh(&hsr->list_lock);
554
555 /* Restart timer */
556 mod_timer(&hsr->prune_timer,
557 jiffies + msecs_to_jiffies(PRUNE_PERIOD));
558}
559
560void *hsr_get_next_node(struct hsr_priv *hsr, void *_pos,
561 unsigned char addr[ETH_ALEN])
562{
563 struct hsr_node *node;
564
565 if (!_pos) {
566 node = list_first_or_null_rcu(&hsr->node_db,
567 struct hsr_node, mac_list);
568 if (node)
569 ether_addr_copy(addr, node->macaddress_A);
570 return node;
571 }
572
573 node = _pos;
574 list_for_each_entry_continue_rcu(node, &hsr->node_db, mac_list) {
575 ether_addr_copy(addr, node->macaddress_A);
576 return node;
577 }
578
579 return NULL;
580}
581
582int hsr_get_node_data(struct hsr_priv *hsr,
583 const unsigned char *addr,
584 unsigned char addr_b[ETH_ALEN],
585 unsigned int *addr_b_ifindex,
586 int *if1_age,
587 u16 *if1_seq,
588 int *if2_age,
589 u16 *if2_seq)
590{
591 struct hsr_node *node;
592 struct hsr_port *port;
593 unsigned long tdiff;
594
595 node = find_node_by_addr_A(&hsr->node_db, addr);
596 if (!node)
597 return -ENOENT;
598
599 ether_addr_copy(addr_b, node->macaddress_B);
600
601 tdiff = jiffies - node->time_in[HSR_PT_SLAVE_A];
602 if (node->time_in_stale[HSR_PT_SLAVE_A])
603 *if1_age = INT_MAX;
604#if HZ <= MSEC_PER_SEC
605 else if (tdiff > msecs_to_jiffies(INT_MAX))
606 *if1_age = INT_MAX;
607#endif
608 else
609 *if1_age = jiffies_to_msecs(tdiff);
610
611 tdiff = jiffies - node->time_in[HSR_PT_SLAVE_B];
612 if (node->time_in_stale[HSR_PT_SLAVE_B])
613 *if2_age = INT_MAX;
614#if HZ <= MSEC_PER_SEC
615 else if (tdiff > msecs_to_jiffies(INT_MAX))
616 *if2_age = INT_MAX;
617#endif
618 else
619 *if2_age = jiffies_to_msecs(tdiff);
620
621 /* Present sequence numbers as if they were incoming on interface */
622 *if1_seq = node->seq_out[HSR_PT_SLAVE_B];
623 *if2_seq = node->seq_out[HSR_PT_SLAVE_A];
624
625 if (node->addr_B_port != HSR_PT_NONE) {
626 port = hsr_port_get_hsr(hsr, node->addr_B_port);
627 *addr_b_ifindex = port->dev->ifindex;
628 } else {
629 *addr_b_ifindex = -1;
630 }
631
632 return 0;
633}