Loading...
Note: File does not exist in v3.1.
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 * Frame router for HSR and PRP.
8 */
9
10#include "hsr_forward.h"
11#include <linux/types.h>
12#include <linux/skbuff.h>
13#include <linux/etherdevice.h>
14#include <linux/if_vlan.h>
15#include "hsr_main.h"
16#include "hsr_framereg.h"
17
18struct hsr_node;
19
20/* The uses I can see for these HSR supervision frames are:
21 * 1) Use the frames that are sent after node initialization ("HSR_TLV.Type =
22 * 22") to reset any sequence_nr counters belonging to that node. Useful if
23 * the other node's counter has been reset for some reason.
24 * --
25 * Or not - resetting the counter and bridging the frame would create a
26 * loop, unfortunately.
27 *
28 * 2) Use the LifeCheck frames to detect ring breaks. I.e. if no LifeCheck
29 * frame is received from a particular node, we know something is wrong.
30 * We just register these (as with normal frames) and throw them away.
31 *
32 * 3) Allow different MAC addresses for the two slave interfaces, using the
33 * MacAddressA field.
34 */
35static bool is_supervision_frame(struct hsr_priv *hsr, struct sk_buff *skb)
36{
37 struct ethhdr *eth_hdr;
38 struct hsr_sup_tag *hsr_sup_tag;
39 struct hsrv1_ethhdr_sp *hsr_V1_hdr;
40
41 WARN_ON_ONCE(!skb_mac_header_was_set(skb));
42 eth_hdr = (struct ethhdr *)skb_mac_header(skb);
43
44 /* Correct addr? */
45 if (!ether_addr_equal(eth_hdr->h_dest,
46 hsr->sup_multicast_addr))
47 return false;
48
49 /* Correct ether type?. */
50 if (!(eth_hdr->h_proto == htons(ETH_P_PRP) ||
51 eth_hdr->h_proto == htons(ETH_P_HSR)))
52 return false;
53
54 /* Get the supervision header from correct location. */
55 if (eth_hdr->h_proto == htons(ETH_P_HSR)) { /* Okay HSRv1. */
56 hsr_V1_hdr = (struct hsrv1_ethhdr_sp *)skb_mac_header(skb);
57 if (hsr_V1_hdr->hsr.encap_proto != htons(ETH_P_PRP))
58 return false;
59
60 hsr_sup_tag = &hsr_V1_hdr->hsr_sup;
61 } else {
62 hsr_sup_tag =
63 &((struct hsrv0_ethhdr_sp *)skb_mac_header(skb))->hsr_sup;
64 }
65
66 if (hsr_sup_tag->HSR_TLV_type != HSR_TLV_ANNOUNCE &&
67 hsr_sup_tag->HSR_TLV_type != HSR_TLV_LIFE_CHECK &&
68 hsr_sup_tag->HSR_TLV_type != PRP_TLV_LIFE_CHECK_DD &&
69 hsr_sup_tag->HSR_TLV_type != PRP_TLV_LIFE_CHECK_DA)
70 return false;
71 if (hsr_sup_tag->HSR_TLV_length != 12 &&
72 hsr_sup_tag->HSR_TLV_length != sizeof(struct hsr_sup_payload))
73 return false;
74
75 return true;
76}
77
78static struct sk_buff *create_stripped_skb_hsr(struct sk_buff *skb_in,
79 struct hsr_frame_info *frame)
80{
81 struct sk_buff *skb;
82 int copylen;
83 unsigned char *dst, *src;
84
85 skb_pull(skb_in, HSR_HLEN);
86 skb = __pskb_copy(skb_in, skb_headroom(skb_in) - HSR_HLEN, GFP_ATOMIC);
87 skb_push(skb_in, HSR_HLEN);
88 if (!skb)
89 return NULL;
90
91 skb_reset_mac_header(skb);
92
93 if (skb->ip_summed == CHECKSUM_PARTIAL)
94 skb->csum_start -= HSR_HLEN;
95
96 copylen = 2 * ETH_ALEN;
97 if (frame->is_vlan)
98 copylen += VLAN_HLEN;
99 src = skb_mac_header(skb_in);
100 dst = skb_mac_header(skb);
101 memcpy(dst, src, copylen);
102
103 skb->protocol = eth_hdr(skb)->h_proto;
104 return skb;
105}
106
107struct sk_buff *hsr_get_untagged_frame(struct hsr_frame_info *frame,
108 struct hsr_port *port)
109{
110 if (!frame->skb_std) {
111 if (frame->skb_hsr) {
112 frame->skb_std =
113 create_stripped_skb_hsr(frame->skb_hsr, frame);
114 } else {
115 /* Unexpected */
116 WARN_ONCE(1, "%s:%d: Unexpected frame received (port_src %s)\n",
117 __FILE__, __LINE__, port->dev->name);
118 return NULL;
119 }
120 }
121
122 return skb_clone(frame->skb_std, GFP_ATOMIC);
123}
124
125struct sk_buff *prp_get_untagged_frame(struct hsr_frame_info *frame,
126 struct hsr_port *port)
127{
128 if (!frame->skb_std) {
129 if (frame->skb_prp) {
130 /* trim the skb by len - HSR_HLEN to exclude RCT */
131 skb_trim(frame->skb_prp,
132 frame->skb_prp->len - HSR_HLEN);
133 frame->skb_std =
134 __pskb_copy(frame->skb_prp,
135 skb_headroom(frame->skb_prp),
136 GFP_ATOMIC);
137 } else {
138 /* Unexpected */
139 WARN_ONCE(1, "%s:%d: Unexpected frame received (port_src %s)\n",
140 __FILE__, __LINE__, port->dev->name);
141 return NULL;
142 }
143 }
144
145 return skb_clone(frame->skb_std, GFP_ATOMIC);
146}
147
148static void prp_set_lan_id(struct prp_rct *trailer,
149 struct hsr_port *port)
150{
151 int lane_id;
152
153 if (port->type == HSR_PT_SLAVE_A)
154 lane_id = 0;
155 else
156 lane_id = 1;
157
158 /* Add net_id in the upper 3 bits of lane_id */
159 lane_id |= port->hsr->net_id;
160 set_prp_lan_id(trailer, lane_id);
161}
162
163/* Tailroom for PRP rct should have been created before calling this */
164static struct sk_buff *prp_fill_rct(struct sk_buff *skb,
165 struct hsr_frame_info *frame,
166 struct hsr_port *port)
167{
168 struct prp_rct *trailer;
169 int min_size = ETH_ZLEN;
170 int lsdu_size;
171
172 if (!skb)
173 return skb;
174
175 if (frame->is_vlan)
176 min_size = VLAN_ETH_ZLEN;
177
178 if (skb_put_padto(skb, min_size))
179 return NULL;
180
181 trailer = (struct prp_rct *)skb_put(skb, HSR_HLEN);
182 lsdu_size = skb->len - 14;
183 if (frame->is_vlan)
184 lsdu_size -= 4;
185 prp_set_lan_id(trailer, port);
186 set_prp_LSDU_size(trailer, lsdu_size);
187 trailer->sequence_nr = htons(frame->sequence_nr);
188 trailer->PRP_suffix = htons(ETH_P_PRP);
189 skb->protocol = eth_hdr(skb)->h_proto;
190
191 return skb;
192}
193
194static void hsr_set_path_id(struct hsr_ethhdr *hsr_ethhdr,
195 struct hsr_port *port)
196{
197 int path_id;
198
199 if (port->type == HSR_PT_SLAVE_A)
200 path_id = 0;
201 else
202 path_id = 1;
203
204 set_hsr_tag_path(&hsr_ethhdr->hsr_tag, path_id);
205}
206
207static struct sk_buff *hsr_fill_tag(struct sk_buff *skb,
208 struct hsr_frame_info *frame,
209 struct hsr_port *port, u8 proto_version)
210{
211 struct hsr_ethhdr *hsr_ethhdr;
212 int lsdu_size;
213
214 /* pad to minimum packet size which is 60 + 6 (HSR tag) */
215 if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN))
216 return NULL;
217
218 lsdu_size = skb->len - 14;
219 if (frame->is_vlan)
220 lsdu_size -= 4;
221
222 hsr_ethhdr = (struct hsr_ethhdr *)skb_mac_header(skb);
223
224 hsr_set_path_id(hsr_ethhdr, port);
225 set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, lsdu_size);
226 hsr_ethhdr->hsr_tag.sequence_nr = htons(frame->sequence_nr);
227 hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
228 hsr_ethhdr->ethhdr.h_proto = htons(proto_version ?
229 ETH_P_HSR : ETH_P_PRP);
230 skb->protocol = hsr_ethhdr->ethhdr.h_proto;
231
232 return skb;
233}
234
235/* If the original frame was an HSR tagged frame, just clone it to be sent
236 * unchanged. Otherwise, create a private frame especially tagged for 'port'.
237 */
238struct sk_buff *hsr_create_tagged_frame(struct hsr_frame_info *frame,
239 struct hsr_port *port)
240{
241 unsigned char *dst, *src;
242 struct sk_buff *skb;
243 int movelen;
244
245 if (frame->skb_hsr) {
246 struct hsr_ethhdr *hsr_ethhdr =
247 (struct hsr_ethhdr *)skb_mac_header(frame->skb_hsr);
248
249 /* set the lane id properly */
250 hsr_set_path_id(hsr_ethhdr, port);
251 return skb_clone(frame->skb_hsr, GFP_ATOMIC);
252 } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
253 return skb_clone(frame->skb_std, GFP_ATOMIC);
254 }
255
256 /* Create the new skb with enough headroom to fit the HSR tag */
257 skb = __pskb_copy(frame->skb_std,
258 skb_headroom(frame->skb_std) + HSR_HLEN, GFP_ATOMIC);
259 if (!skb)
260 return NULL;
261 skb_reset_mac_header(skb);
262
263 if (skb->ip_summed == CHECKSUM_PARTIAL)
264 skb->csum_start += HSR_HLEN;
265
266 movelen = ETH_HLEN;
267 if (frame->is_vlan)
268 movelen += VLAN_HLEN;
269
270 src = skb_mac_header(skb);
271 dst = skb_push(skb, HSR_HLEN);
272 memmove(dst, src, movelen);
273 skb_reset_mac_header(skb);
274
275 /* skb_put_padto free skb on error and hsr_fill_tag returns NULL in
276 * that case
277 */
278 return hsr_fill_tag(skb, frame, port, port->hsr->prot_version);
279}
280
281struct sk_buff *prp_create_tagged_frame(struct hsr_frame_info *frame,
282 struct hsr_port *port)
283{
284 struct sk_buff *skb;
285
286 if (frame->skb_prp) {
287 struct prp_rct *trailer = skb_get_PRP_rct(frame->skb_prp);
288
289 if (trailer) {
290 prp_set_lan_id(trailer, port);
291 } else {
292 WARN_ONCE(!trailer, "errored PRP skb");
293 return NULL;
294 }
295 return skb_clone(frame->skb_prp, GFP_ATOMIC);
296 } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
297 return skb_clone(frame->skb_std, GFP_ATOMIC);
298 }
299
300 skb = skb_copy_expand(frame->skb_std, 0,
301 skb_tailroom(frame->skb_std) + HSR_HLEN,
302 GFP_ATOMIC);
303 prp_fill_rct(skb, frame, port);
304
305 return skb;
306}
307
308static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev,
309 struct hsr_node *node_src)
310{
311 bool was_multicast_frame;
312 int res;
313
314 was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST);
315 hsr_addr_subst_source(node_src, skb);
316 skb_pull(skb, ETH_HLEN);
317 res = netif_rx(skb);
318 if (res == NET_RX_DROP) {
319 dev->stats.rx_dropped++;
320 } else {
321 dev->stats.rx_packets++;
322 dev->stats.rx_bytes += skb->len;
323 if (was_multicast_frame)
324 dev->stats.multicast++;
325 }
326}
327
328static int hsr_xmit(struct sk_buff *skb, struct hsr_port *port,
329 struct hsr_frame_info *frame)
330{
331 if (frame->port_rcv->type == HSR_PT_MASTER) {
332 hsr_addr_subst_dest(frame->node_src, skb, port);
333
334 /* Address substitution (IEC62439-3 pp 26, 50): replace mac
335 * address of outgoing frame with that of the outgoing slave's.
336 */
337 ether_addr_copy(eth_hdr(skb)->h_source, port->dev->dev_addr);
338 }
339 return dev_queue_xmit(skb);
340}
341
342bool prp_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
343{
344 return ((frame->port_rcv->type == HSR_PT_SLAVE_A &&
345 port->type == HSR_PT_SLAVE_B) ||
346 (frame->port_rcv->type == HSR_PT_SLAVE_B &&
347 port->type == HSR_PT_SLAVE_A));
348}
349
350bool hsr_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
351{
352 if (port->dev->features & NETIF_F_HW_HSR_FWD)
353 return prp_drop_frame(frame, port);
354
355 return false;
356}
357
358/* Forward the frame through all devices except:
359 * - Back through the receiving device
360 * - If it's a HSR frame: through a device where it has passed before
361 * - if it's a PRP frame: through another PRP slave device (no bridge)
362 * - To the local HSR master only if the frame is directly addressed to it, or
363 * a non-supervision multicast or broadcast frame.
364 *
365 * HSR slave devices should insert a HSR tag into the frame, or forward the
366 * frame unchanged if it's already tagged. Interlink devices should strip HSR
367 * tags if they're of the non-HSR type (but only after duplicate discard). The
368 * master device always strips HSR tags.
369 */
370static void hsr_forward_do(struct hsr_frame_info *frame)
371{
372 struct hsr_port *port;
373 struct sk_buff *skb;
374 bool sent = false;
375
376 hsr_for_each_port(frame->port_rcv->hsr, port) {
377 struct hsr_priv *hsr = port->hsr;
378 /* Don't send frame back the way it came */
379 if (port == frame->port_rcv)
380 continue;
381
382 /* Don't deliver locally unless we should */
383 if (port->type == HSR_PT_MASTER && !frame->is_local_dest)
384 continue;
385
386 /* Deliver frames directly addressed to us to master only */
387 if (port->type != HSR_PT_MASTER && frame->is_local_exclusive)
388 continue;
389
390 /* If hardware duplicate generation is enabled, only send out
391 * one port.
392 */
393 if ((port->dev->features & NETIF_F_HW_HSR_DUP) && sent)
394 continue;
395
396 /* Don't send frame over port where it has been sent before.
397 * Also fro SAN, this shouldn't be done.
398 */
399 if (!frame->is_from_san &&
400 hsr_register_frame_out(port, frame->node_src,
401 frame->sequence_nr))
402 continue;
403
404 if (frame->is_supervision && port->type == HSR_PT_MASTER) {
405 hsr_handle_sup_frame(frame);
406 continue;
407 }
408
409 /* Check if frame is to be dropped. Eg. for PRP no forward
410 * between ports.
411 */
412 if (hsr->proto_ops->drop_frame &&
413 hsr->proto_ops->drop_frame(frame, port))
414 continue;
415
416 if (port->type != HSR_PT_MASTER)
417 skb = hsr->proto_ops->create_tagged_frame(frame, port);
418 else
419 skb = hsr->proto_ops->get_untagged_frame(frame, port);
420
421 if (!skb) {
422 frame->port_rcv->dev->stats.rx_dropped++;
423 continue;
424 }
425
426 skb->dev = port->dev;
427 if (port->type == HSR_PT_MASTER) {
428 hsr_deliver_master(skb, port->dev, frame->node_src);
429 } else {
430 if (!hsr_xmit(skb, port, frame))
431 sent = true;
432 }
433 }
434}
435
436static void check_local_dest(struct hsr_priv *hsr, struct sk_buff *skb,
437 struct hsr_frame_info *frame)
438{
439 if (hsr_addr_is_self(hsr, eth_hdr(skb)->h_dest)) {
440 frame->is_local_exclusive = true;
441 skb->pkt_type = PACKET_HOST;
442 } else {
443 frame->is_local_exclusive = false;
444 }
445
446 if (skb->pkt_type == PACKET_HOST ||
447 skb->pkt_type == PACKET_MULTICAST ||
448 skb->pkt_type == PACKET_BROADCAST) {
449 frame->is_local_dest = true;
450 } else {
451 frame->is_local_dest = false;
452 }
453}
454
455static void handle_std_frame(struct sk_buff *skb,
456 struct hsr_frame_info *frame)
457{
458 struct hsr_port *port = frame->port_rcv;
459 struct hsr_priv *hsr = port->hsr;
460 unsigned long irqflags;
461
462 frame->skb_hsr = NULL;
463 frame->skb_prp = NULL;
464 frame->skb_std = skb;
465
466 if (port->type != HSR_PT_MASTER) {
467 frame->is_from_san = true;
468 } else {
469 /* Sequence nr for the master node */
470 spin_lock_irqsave(&hsr->seqnr_lock, irqflags);
471 frame->sequence_nr = hsr->sequence_nr;
472 hsr->sequence_nr++;
473 spin_unlock_irqrestore(&hsr->seqnr_lock, irqflags);
474 }
475}
476
477int hsr_fill_frame_info(__be16 proto, struct sk_buff *skb,
478 struct hsr_frame_info *frame)
479{
480 struct hsr_port *port = frame->port_rcv;
481 struct hsr_priv *hsr = port->hsr;
482
483 /* HSRv0 supervisory frames double as a tag so treat them as tagged. */
484 if ((!hsr->prot_version && proto == htons(ETH_P_PRP)) ||
485 proto == htons(ETH_P_HSR)) {
486 /* Check if skb contains hsr_ethhdr */
487 if (skb->mac_len < sizeof(struct hsr_ethhdr))
488 return -EINVAL;
489
490 /* HSR tagged frame :- Data or Supervision */
491 frame->skb_std = NULL;
492 frame->skb_prp = NULL;
493 frame->skb_hsr = skb;
494 frame->sequence_nr = hsr_get_skb_sequence_nr(skb);
495 return 0;
496 }
497
498 /* Standard frame or PRP from master port */
499 handle_std_frame(skb, frame);
500
501 return 0;
502}
503
504int prp_fill_frame_info(__be16 proto, struct sk_buff *skb,
505 struct hsr_frame_info *frame)
506{
507 /* Supervision frame */
508 struct prp_rct *rct = skb_get_PRP_rct(skb);
509
510 if (rct &&
511 prp_check_lsdu_size(skb, rct, frame->is_supervision)) {
512 frame->skb_hsr = NULL;
513 frame->skb_std = NULL;
514 frame->skb_prp = skb;
515 frame->sequence_nr = prp_get_skb_sequence_nr(rct);
516 return 0;
517 }
518 handle_std_frame(skb, frame);
519
520 return 0;
521}
522
523static int fill_frame_info(struct hsr_frame_info *frame,
524 struct sk_buff *skb, struct hsr_port *port)
525{
526 struct hsr_priv *hsr = port->hsr;
527 struct hsr_vlan_ethhdr *vlan_hdr;
528 struct ethhdr *ethhdr;
529 __be16 proto;
530 int ret;
531
532 /* Check if skb contains ethhdr */
533 if (skb->mac_len < sizeof(struct ethhdr))
534 return -EINVAL;
535
536 memset(frame, 0, sizeof(*frame));
537 frame->is_supervision = is_supervision_frame(port->hsr, skb);
538 frame->node_src = hsr_get_node(port, &hsr->node_db, skb,
539 frame->is_supervision,
540 port->type);
541 if (!frame->node_src)
542 return -1; /* Unknown node and !is_supervision, or no mem */
543
544 ethhdr = (struct ethhdr *)skb_mac_header(skb);
545 frame->is_vlan = false;
546 proto = ethhdr->h_proto;
547
548 if (proto == htons(ETH_P_8021Q))
549 frame->is_vlan = true;
550
551 if (frame->is_vlan) {
552 vlan_hdr = (struct hsr_vlan_ethhdr *)ethhdr;
553 proto = vlan_hdr->vlanhdr.h_vlan_encapsulated_proto;
554 /* FIXME: */
555 netdev_warn_once(skb->dev, "VLAN not yet supported");
556 }
557
558 frame->is_from_san = false;
559 frame->port_rcv = port;
560 ret = hsr->proto_ops->fill_frame_info(proto, skb, frame);
561 if (ret)
562 return ret;
563
564 check_local_dest(port->hsr, skb, frame);
565
566 return 0;
567}
568
569/* Must be called holding rcu read lock (because of the port parameter) */
570void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port)
571{
572 struct hsr_frame_info frame;
573
574 if (fill_frame_info(&frame, skb, port) < 0)
575 goto out_drop;
576
577 hsr_register_frame_in(frame.node_src, port, frame.sequence_nr);
578 hsr_forward_do(&frame);
579 /* Gets called for ingress frames as well as egress from master port.
580 * So check and increment stats for master port only here.
581 */
582 if (port->type == HSR_PT_MASTER) {
583 port->dev->stats.tx_packets++;
584 port->dev->stats.tx_bytes += skb->len;
585 }
586
587 kfree_skb(frame.skb_hsr);
588 kfree_skb(frame.skb_prp);
589 kfree_skb(frame.skb_std);
590 return;
591
592out_drop:
593 port->dev->stats.tx_dropped++;
594 kfree_skb(skb);
595}