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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 /* Check if skb contains hsr_ethhdr */
232 if (skb->mac_len < sizeof(struct hsr_ethhdr))
233 return NULL;
234
235 /* Use the existing sequence_nr from the tag as starting point
236 * for filtering duplicate frames.
237 */
238 seq_out = hsr_get_skb_sequence_nr(skb) - 1;
239 } else {
240 rct = skb_get_PRP_rct(skb);
241 if (rct && prp_check_lsdu_size(skb, rct, is_sup)) {
242 seq_out = prp_get_skb_sequence_nr(rct);
243 } else {
244 if (rx_port != HSR_PT_MASTER)
245 san = true;
246 seq_out = HSR_SEQNR_START;
247 }
248 }
249
250 return hsr_add_node(hsr, node_db, ethhdr->h_source, seq_out,
251 san, rx_port);
252}
253
254/* Use the Supervision frame's info about an eventual macaddress_B for merging
255 * nodes that has previously had their macaddress_B registered as a separate
256 * node.
257 */
258void hsr_handle_sup_frame(struct hsr_frame_info *frame)
259{
260 struct hsr_node *node_curr = frame->node_src;
261 struct hsr_port *port_rcv = frame->port_rcv;
262 struct hsr_priv *hsr = port_rcv->hsr;
263 struct hsr_sup_payload *hsr_sp;
264 struct hsr_sup_tlv *hsr_sup_tlv;
265 struct hsr_node *node_real;
266 struct sk_buff *skb = NULL;
267 struct list_head *node_db;
268 struct ethhdr *ethhdr;
269 int i;
270 unsigned int pull_size = 0;
271 unsigned int total_pull_size = 0;
272
273 /* Here either frame->skb_hsr or frame->skb_prp should be
274 * valid as supervision frame always will have protocol
275 * header info.
276 */
277 if (frame->skb_hsr)
278 skb = frame->skb_hsr;
279 else if (frame->skb_prp)
280 skb = frame->skb_prp;
281 else if (frame->skb_std)
282 skb = frame->skb_std;
283 if (!skb)
284 return;
285
286 /* Leave the ethernet header. */
287 pull_size = sizeof(struct ethhdr);
288 skb_pull(skb, pull_size);
289 total_pull_size += pull_size;
290
291 ethhdr = (struct ethhdr *)skb_mac_header(skb);
292
293 /* And leave the HSR tag. */
294 if (ethhdr->h_proto == htons(ETH_P_HSR)) {
295 pull_size = sizeof(struct hsr_tag);
296 skb_pull(skb, pull_size);
297 total_pull_size += pull_size;
298 }
299
300 /* And leave the HSR sup tag. */
301 pull_size = sizeof(struct hsr_sup_tag);
302 skb_pull(skb, pull_size);
303 total_pull_size += pull_size;
304
305 /* get HSR sup payload */
306 hsr_sp = (struct hsr_sup_payload *)skb->data;
307
308 /* Merge node_curr (registered on macaddress_B) into node_real */
309 node_db = &port_rcv->hsr->node_db;
310 node_real = find_node_by_addr_A(node_db, hsr_sp->macaddress_A);
311 if (!node_real)
312 /* No frame received from AddrA of this node yet */
313 node_real = hsr_add_node(hsr, node_db, hsr_sp->macaddress_A,
314 HSR_SEQNR_START - 1, true,
315 port_rcv->type);
316 if (!node_real)
317 goto done; /* No mem */
318 if (node_real == node_curr)
319 /* Node has already been merged */
320 goto done;
321
322 /* Leave the first HSR sup payload. */
323 pull_size = sizeof(struct hsr_sup_payload);
324 skb_pull(skb, pull_size);
325 total_pull_size += pull_size;
326
327 /* Get second supervision tlv */
328 hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
329 /* And check if it is a redbox mac TLV */
330 if (hsr_sup_tlv->HSR_TLV_type == PRP_TLV_REDBOX_MAC) {
331 /* We could stop here after pushing hsr_sup_payload,
332 * or proceed and allow macaddress_B and for redboxes.
333 */
334 /* Sanity check length */
335 if (hsr_sup_tlv->HSR_TLV_length != 6)
336 goto done;
337
338 /* Leave the second HSR sup tlv. */
339 pull_size = sizeof(struct hsr_sup_tlv);
340 skb_pull(skb, pull_size);
341 total_pull_size += pull_size;
342
343 /* Get redbox mac address. */
344 hsr_sp = (struct hsr_sup_payload *)skb->data;
345
346 /* Check if redbox mac and node mac are equal. */
347 if (!ether_addr_equal(node_real->macaddress_A, hsr_sp->macaddress_A)) {
348 /* This is a redbox supervision frame for a VDAN! */
349 goto done;
350 }
351 }
352
353 ether_addr_copy(node_real->macaddress_B, ethhdr->h_source);
354 spin_lock_bh(&node_real->seq_out_lock);
355 for (i = 0; i < HSR_PT_PORTS; i++) {
356 if (!node_curr->time_in_stale[i] &&
357 time_after(node_curr->time_in[i], node_real->time_in[i])) {
358 node_real->time_in[i] = node_curr->time_in[i];
359 node_real->time_in_stale[i] =
360 node_curr->time_in_stale[i];
361 }
362 if (seq_nr_after(node_curr->seq_out[i], node_real->seq_out[i]))
363 node_real->seq_out[i] = node_curr->seq_out[i];
364 }
365 spin_unlock_bh(&node_real->seq_out_lock);
366 node_real->addr_B_port = port_rcv->type;
367
368 spin_lock_bh(&hsr->list_lock);
369 if (!node_curr->removed) {
370 list_del_rcu(&node_curr->mac_list);
371 node_curr->removed = true;
372 kfree_rcu(node_curr, rcu_head);
373 }
374 spin_unlock_bh(&hsr->list_lock);
375
376done:
377 /* Push back here */
378 skb_push(skb, total_pull_size);
379}
380
381/* 'skb' is a frame meant for this host, that is to be passed to upper layers.
382 *
383 * If the frame was sent by a node's B interface, replace the source
384 * address with that node's "official" address (macaddress_A) so that upper
385 * layers recognize where it came from.
386 */
387void hsr_addr_subst_source(struct hsr_node *node, struct sk_buff *skb)
388{
389 if (!skb_mac_header_was_set(skb)) {
390 WARN_ONCE(1, "%s: Mac header not set\n", __func__);
391 return;
392 }
393
394 memcpy(ð_hdr(skb)->h_source, node->macaddress_A, ETH_ALEN);
395}
396
397/* 'skb' is a frame meant for another host.
398 * 'port' is the outgoing interface
399 *
400 * Substitute the target (dest) MAC address if necessary, so the it matches the
401 * recipient interface MAC address, regardless of whether that is the
402 * recipient's A or B interface.
403 * This is needed to keep the packets flowing through switches that learn on
404 * which "side" the different interfaces are.
405 */
406void hsr_addr_subst_dest(struct hsr_node *node_src, struct sk_buff *skb,
407 struct hsr_port *port)
408{
409 struct hsr_node *node_dst;
410
411 if (!skb_mac_header_was_set(skb)) {
412 WARN_ONCE(1, "%s: Mac header not set\n", __func__);
413 return;
414 }
415
416 if (!is_unicast_ether_addr(eth_hdr(skb)->h_dest))
417 return;
418
419 node_dst = find_node_by_addr_A(&port->hsr->node_db,
420 eth_hdr(skb)->h_dest);
421 if (!node_dst) {
422 if (port->hsr->prot_version != PRP_V1 && net_ratelimit())
423 netdev_err(skb->dev, "%s: Unknown node\n", __func__);
424 return;
425 }
426 if (port->type != node_dst->addr_B_port)
427 return;
428
429 if (is_valid_ether_addr(node_dst->macaddress_B))
430 ether_addr_copy(eth_hdr(skb)->h_dest, node_dst->macaddress_B);
431}
432
433void hsr_register_frame_in(struct hsr_node *node, struct hsr_port *port,
434 u16 sequence_nr)
435{
436 /* Don't register incoming frames without a valid sequence number. This
437 * ensures entries of restarted nodes gets pruned so that they can
438 * re-register and resume communications.
439 */
440 if (!(port->dev->features & NETIF_F_HW_HSR_TAG_RM) &&
441 seq_nr_before(sequence_nr, node->seq_out[port->type]))
442 return;
443
444 node->time_in[port->type] = jiffies;
445 node->time_in_stale[port->type] = false;
446}
447
448/* 'skb' is a HSR Ethernet frame (with a HSR tag inserted), with a valid
449 * ethhdr->h_source address and skb->mac_header set.
450 *
451 * Return:
452 * 1 if frame can be shown to have been sent recently on this interface,
453 * 0 otherwise, or
454 * negative error code on error
455 */
456int hsr_register_frame_out(struct hsr_port *port, struct hsr_node *node,
457 u16 sequence_nr)
458{
459 spin_lock_bh(&node->seq_out_lock);
460 if (seq_nr_before_or_eq(sequence_nr, node->seq_out[port->type]) &&
461 time_is_after_jiffies(node->time_out[port->type] +
462 msecs_to_jiffies(HSR_ENTRY_FORGET_TIME))) {
463 spin_unlock_bh(&node->seq_out_lock);
464 return 1;
465 }
466
467 node->time_out[port->type] = jiffies;
468 node->seq_out[port->type] = sequence_nr;
469 spin_unlock_bh(&node->seq_out_lock);
470 return 0;
471}
472
473static struct hsr_port *get_late_port(struct hsr_priv *hsr,
474 struct hsr_node *node)
475{
476 if (node->time_in_stale[HSR_PT_SLAVE_A])
477 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
478 if (node->time_in_stale[HSR_PT_SLAVE_B])
479 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
480
481 if (time_after(node->time_in[HSR_PT_SLAVE_B],
482 node->time_in[HSR_PT_SLAVE_A] +
483 msecs_to_jiffies(MAX_SLAVE_DIFF)))
484 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
485 if (time_after(node->time_in[HSR_PT_SLAVE_A],
486 node->time_in[HSR_PT_SLAVE_B] +
487 msecs_to_jiffies(MAX_SLAVE_DIFF)))
488 return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
489
490 return NULL;
491}
492
493/* Remove stale sequence_nr records. Called by timer every
494 * HSR_LIFE_CHECK_INTERVAL (two seconds or so).
495 */
496void hsr_prune_nodes(struct timer_list *t)
497{
498 struct hsr_priv *hsr = from_timer(hsr, t, prune_timer);
499 struct hsr_node *node;
500 struct hsr_node *tmp;
501 struct hsr_port *port;
502 unsigned long timestamp;
503 unsigned long time_a, time_b;
504
505 spin_lock_bh(&hsr->list_lock);
506 list_for_each_entry_safe(node, tmp, &hsr->node_db, mac_list) {
507 /* Don't prune own node. Neither time_in[HSR_PT_SLAVE_A]
508 * nor time_in[HSR_PT_SLAVE_B], will ever be updated for
509 * the master port. Thus the master node will be repeatedly
510 * pruned leading to packet loss.
511 */
512 if (hsr_addr_is_self(hsr, node->macaddress_A))
513 continue;
514
515 /* Shorthand */
516 time_a = node->time_in[HSR_PT_SLAVE_A];
517 time_b = node->time_in[HSR_PT_SLAVE_B];
518
519 /* Check for timestamps old enough to risk wrap-around */
520 if (time_after(jiffies, time_a + MAX_JIFFY_OFFSET / 2))
521 node->time_in_stale[HSR_PT_SLAVE_A] = true;
522 if (time_after(jiffies, time_b + MAX_JIFFY_OFFSET / 2))
523 node->time_in_stale[HSR_PT_SLAVE_B] = true;
524
525 /* Get age of newest frame from node.
526 * At least one time_in is OK here; nodes get pruned long
527 * before both time_ins can get stale
528 */
529 timestamp = time_a;
530 if (node->time_in_stale[HSR_PT_SLAVE_A] ||
531 (!node->time_in_stale[HSR_PT_SLAVE_B] &&
532 time_after(time_b, time_a)))
533 timestamp = time_b;
534
535 /* Warn of ring error only as long as we get frames at all */
536 if (time_is_after_jiffies(timestamp +
537 msecs_to_jiffies(1.5 * MAX_SLAVE_DIFF))) {
538 rcu_read_lock();
539 port = get_late_port(hsr, node);
540 if (port)
541 hsr_nl_ringerror(hsr, node->macaddress_A, port);
542 rcu_read_unlock();
543 }
544
545 /* Prune old entries */
546 if (time_is_before_jiffies(timestamp +
547 msecs_to_jiffies(HSR_NODE_FORGET_TIME))) {
548 hsr_nl_nodedown(hsr, node->macaddress_A);
549 if (!node->removed) {
550 list_del_rcu(&node->mac_list);
551 node->removed = true;
552 /* Note that we need to free this entry later: */
553 kfree_rcu(node, rcu_head);
554 }
555 }
556 }
557 spin_unlock_bh(&hsr->list_lock);
558
559 /* Restart timer */
560 mod_timer(&hsr->prune_timer,
561 jiffies + msecs_to_jiffies(PRUNE_PERIOD));
562}
563
564void *hsr_get_next_node(struct hsr_priv *hsr, void *_pos,
565 unsigned char addr[ETH_ALEN])
566{
567 struct hsr_node *node;
568
569 if (!_pos) {
570 node = list_first_or_null_rcu(&hsr->node_db,
571 struct hsr_node, mac_list);
572 if (node)
573 ether_addr_copy(addr, node->macaddress_A);
574 return node;
575 }
576
577 node = _pos;
578 list_for_each_entry_continue_rcu(node, &hsr->node_db, mac_list) {
579 ether_addr_copy(addr, node->macaddress_A);
580 return node;
581 }
582
583 return NULL;
584}
585
586int hsr_get_node_data(struct hsr_priv *hsr,
587 const unsigned char *addr,
588 unsigned char addr_b[ETH_ALEN],
589 unsigned int *addr_b_ifindex,
590 int *if1_age,
591 u16 *if1_seq,
592 int *if2_age,
593 u16 *if2_seq)
594{
595 struct hsr_node *node;
596 struct hsr_port *port;
597 unsigned long tdiff;
598
599 node = find_node_by_addr_A(&hsr->node_db, addr);
600 if (!node)
601 return -ENOENT;
602
603 ether_addr_copy(addr_b, node->macaddress_B);
604
605 tdiff = jiffies - node->time_in[HSR_PT_SLAVE_A];
606 if (node->time_in_stale[HSR_PT_SLAVE_A])
607 *if1_age = INT_MAX;
608#if HZ <= MSEC_PER_SEC
609 else if (tdiff > msecs_to_jiffies(INT_MAX))
610 *if1_age = INT_MAX;
611#endif
612 else
613 *if1_age = jiffies_to_msecs(tdiff);
614
615 tdiff = jiffies - node->time_in[HSR_PT_SLAVE_B];
616 if (node->time_in_stale[HSR_PT_SLAVE_B])
617 *if2_age = INT_MAX;
618#if HZ <= MSEC_PER_SEC
619 else if (tdiff > msecs_to_jiffies(INT_MAX))
620 *if2_age = INT_MAX;
621#endif
622 else
623 *if2_age = jiffies_to_msecs(tdiff);
624
625 /* Present sequence numbers as if they were incoming on interface */
626 *if1_seq = node->seq_out[HSR_PT_SLAVE_B];
627 *if2_seq = node->seq_out[HSR_PT_SLAVE_A];
628
629 if (node->addr_B_port != HSR_PT_NONE) {
630 port = hsr_port_get_hsr(hsr, node->addr_B_port);
631 *addr_b_ifindex = port->dev->ifindex;
632 } else {
633 *addr_b_ifindex = -1;
634 }
635
636 return 0;
637}