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 struct hsr_sup_tlv *hsr_sup_tlv;
41 u16 total_length = 0;
42
43 WARN_ON_ONCE(!skb_mac_header_was_set(skb));
44 eth_hdr = (struct ethhdr *)skb_mac_header(skb);
45
46 /* Correct addr? */
47 if (!ether_addr_equal(addr1: eth_hdr->h_dest,
48 addr2: hsr->sup_multicast_addr))
49 return false;
50
51 /* Correct ether type?. */
52 if (!(eth_hdr->h_proto == htons(ETH_P_PRP) ||
53 eth_hdr->h_proto == htons(ETH_P_HSR)))
54 return false;
55
56 /* Get the supervision header from correct location. */
57 if (eth_hdr->h_proto == htons(ETH_P_HSR)) { /* Okay HSRv1. */
58 total_length = sizeof(struct hsrv1_ethhdr_sp);
59 if (!pskb_may_pull(skb, len: total_length))
60 return false;
61
62 hsr_V1_hdr = (struct hsrv1_ethhdr_sp *)skb_mac_header(skb);
63 if (hsr_V1_hdr->hsr.encap_proto != htons(ETH_P_PRP))
64 return false;
65
66 hsr_sup_tag = &hsr_V1_hdr->hsr_sup;
67 } else {
68 total_length = sizeof(struct hsrv0_ethhdr_sp);
69 if (!pskb_may_pull(skb, len: total_length))
70 return false;
71
72 hsr_sup_tag =
73 &((struct hsrv0_ethhdr_sp *)skb_mac_header(skb))->hsr_sup;
74 }
75
76 if (hsr_sup_tag->tlv.HSR_TLV_type != HSR_TLV_ANNOUNCE &&
77 hsr_sup_tag->tlv.HSR_TLV_type != HSR_TLV_LIFE_CHECK &&
78 hsr_sup_tag->tlv.HSR_TLV_type != PRP_TLV_LIFE_CHECK_DD &&
79 hsr_sup_tag->tlv.HSR_TLV_type != PRP_TLV_LIFE_CHECK_DA)
80 return false;
81 if (hsr_sup_tag->tlv.HSR_TLV_length != 12 &&
82 hsr_sup_tag->tlv.HSR_TLV_length != sizeof(struct hsr_sup_payload))
83 return false;
84
85 /* Get next tlv */
86 total_length += hsr_sup_tag->tlv.HSR_TLV_length;
87 if (!pskb_may_pull(skb, len: total_length))
88 return false;
89 skb_pull(skb, len: total_length);
90 hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
91 skb_push(skb, len: total_length);
92
93 /* if this is a redbox supervision frame we need to verify
94 * that more data is available
95 */
96 if (hsr_sup_tlv->HSR_TLV_type == PRP_TLV_REDBOX_MAC) {
97 /* tlv length must be a length of a mac address */
98 if (hsr_sup_tlv->HSR_TLV_length != sizeof(struct hsr_sup_payload))
99 return false;
100
101 /* make sure another tlv follows */
102 total_length += sizeof(struct hsr_sup_tlv) + hsr_sup_tlv->HSR_TLV_length;
103 if (!pskb_may_pull(skb, len: total_length))
104 return false;
105
106 /* get next tlv */
107 skb_pull(skb, len: total_length);
108 hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
109 skb_push(skb, len: total_length);
110 }
111
112 /* end of tlvs must follow at the end */
113 if (hsr_sup_tlv->HSR_TLV_type == HSR_TLV_EOT &&
114 hsr_sup_tlv->HSR_TLV_length != 0)
115 return false;
116
117 return true;
118}
119
120static bool is_proxy_supervision_frame(struct hsr_priv *hsr,
121 struct sk_buff *skb)
122{
123 struct hsr_sup_payload *payload;
124 struct ethhdr *eth_hdr;
125 u16 total_length = 0;
126
127 eth_hdr = (struct ethhdr *)skb_mac_header(skb);
128
129 /* Get the HSR protocol revision. */
130 if (eth_hdr->h_proto == htons(ETH_P_HSR))
131 total_length = sizeof(struct hsrv1_ethhdr_sp);
132 else
133 total_length = sizeof(struct hsrv0_ethhdr_sp);
134
135 if (!pskb_may_pull(skb, len: total_length + sizeof(struct hsr_sup_payload)))
136 return false;
137
138 skb_pull(skb, len: total_length);
139 payload = (struct hsr_sup_payload *)skb->data;
140 skb_push(skb, len: total_length);
141
142 /* For RedBox (HSR-SAN) check if we have received the supervision
143 * frame with MAC addresses from own ProxyNodeTable.
144 */
145 return hsr_is_node_in_db(node_db: &hsr->proxy_node_db,
146 addr: payload->macaddress_A);
147}
148
149static struct sk_buff *create_stripped_skb_hsr(struct sk_buff *skb_in,
150 struct hsr_frame_info *frame)
151{
152 struct sk_buff *skb;
153 int copylen;
154 unsigned char *dst, *src;
155
156 skb_pull(skb: skb_in, HSR_HLEN);
157 skb = __pskb_copy(skb: skb_in, headroom: skb_headroom(skb: skb_in) - HSR_HLEN, GFP_ATOMIC);
158 skb_push(skb: skb_in, HSR_HLEN);
159 if (!skb)
160 return NULL;
161
162 skb_reset_mac_header(skb);
163
164 if (skb->ip_summed == CHECKSUM_PARTIAL)
165 skb->csum_start -= HSR_HLEN;
166
167 copylen = 2 * ETH_ALEN;
168 if (frame->is_vlan)
169 copylen += VLAN_HLEN;
170 src = skb_mac_header(skb: skb_in);
171 dst = skb_mac_header(skb);
172 memcpy(dst, src, copylen);
173
174 skb->protocol = eth_hdr(skb)->h_proto;
175 return skb;
176}
177
178struct sk_buff *hsr_get_untagged_frame(struct hsr_frame_info *frame,
179 struct hsr_port *port)
180{
181 if (!frame->skb_std) {
182 if (frame->skb_hsr)
183 frame->skb_std =
184 create_stripped_skb_hsr(skb_in: frame->skb_hsr, frame);
185 else
186 netdev_warn_once(port->dev,
187 "Unexpected frame received in hsr_get_untagged_frame()\n");
188
189 if (!frame->skb_std)
190 return NULL;
191 }
192
193 return skb_clone(skb: frame->skb_std, GFP_ATOMIC);
194}
195
196struct sk_buff *prp_get_untagged_frame(struct hsr_frame_info *frame,
197 struct hsr_port *port)
198{
199 if (!frame->skb_std) {
200 if (frame->skb_prp) {
201 /* trim the skb by len - HSR_HLEN to exclude RCT */
202 skb_trim(skb: frame->skb_prp,
203 len: frame->skb_prp->len - HSR_HLEN);
204 frame->skb_std =
205 __pskb_copy(skb: frame->skb_prp,
206 headroom: skb_headroom(skb: frame->skb_prp),
207 GFP_ATOMIC);
208 if (!frame->skb_std)
209 return NULL;
210 } else {
211 /* Unexpected */
212 WARN_ONCE(1, "%s:%d: Unexpected frame received (port_src %s)\n",
213 __FILE__, __LINE__, port->dev->name);
214 return NULL;
215 }
216 }
217
218 return skb_clone(skb: frame->skb_std, GFP_ATOMIC);
219}
220
221static void prp_set_lan_id(struct prp_rct *trailer,
222 struct hsr_port *port)
223{
224 int lane_id;
225
226 if (port->type == HSR_PT_SLAVE_A)
227 lane_id = 0;
228 else
229 lane_id = 1;
230
231 /* Add net_id in the upper 3 bits of lane_id */
232 lane_id |= port->hsr->net_id;
233 set_prp_lan_id(rct: trailer, lan_id: lane_id);
234}
235
236/* Tailroom for PRP rct should have been created before calling this */
237static struct sk_buff *prp_fill_rct(struct sk_buff *skb,
238 struct hsr_frame_info *frame,
239 struct hsr_port *port)
240{
241 struct prp_rct *trailer;
242 int min_size = ETH_ZLEN;
243 int lsdu_size;
244
245 if (!skb)
246 return skb;
247
248 if (frame->is_vlan)
249 min_size = VLAN_ETH_ZLEN;
250
251 if (skb_put_padto(skb, len: min_size))
252 return NULL;
253
254 trailer = (struct prp_rct *)skb_put(skb, HSR_HLEN);
255 lsdu_size = skb->len - 14;
256 if (frame->is_vlan)
257 lsdu_size -= 4;
258 prp_set_lan_id(trailer, port);
259 set_prp_LSDU_size(rct: trailer, LSDU_size: lsdu_size);
260 trailer->sequence_nr = htons(frame->sequence_nr);
261 trailer->PRP_suffix = htons(ETH_P_PRP);
262 skb->protocol = eth_hdr(skb)->h_proto;
263
264 return skb;
265}
266
267static void hsr_set_path_id(struct hsr_frame_info *frame,
268 struct hsr_ethhdr *hsr_ethhdr,
269 struct hsr_port *port)
270{
271 int path_id;
272
273 if (port->hsr->prot_version) {
274 if (port->type == HSR_PT_SLAVE_A)
275 path_id = 0;
276 else
277 path_id = 1;
278 } else {
279 if (frame->is_supervision)
280 path_id = 0xf;
281 else
282 path_id = 1;
283 }
284
285 set_hsr_tag_path(ht: &hsr_ethhdr->hsr_tag, path: path_id);
286}
287
288static struct sk_buff *hsr_fill_tag(struct sk_buff *skb,
289 struct hsr_frame_info *frame,
290 struct hsr_port *port, u8 proto_version)
291{
292 struct hsr_ethhdr *hsr_ethhdr;
293 unsigned char *pc;
294 int lsdu_size;
295
296 /* pad to minimum packet size which is 60 + 6 (HSR tag) */
297 if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN))
298 return NULL;
299
300 lsdu_size = skb->len - 14;
301 if (frame->is_vlan)
302 lsdu_size -= 4;
303
304 pc = skb_mac_header(skb);
305 if (frame->is_vlan)
306 /* This 4-byte shift (size of a vlan tag) does not
307 * mean that the ethhdr starts there. But rather it
308 * provides the proper environment for accessing
309 * the fields, such as hsr_tag etc., just like
310 * when the vlan tag is not there. This is because
311 * the hsr tag is after the vlan tag.
312 */
313 hsr_ethhdr = (struct hsr_ethhdr *)(pc + VLAN_HLEN);
314 else
315 hsr_ethhdr = (struct hsr_ethhdr *)pc;
316
317 hsr_set_path_id(frame, hsr_ethhdr, port);
318 set_hsr_tag_LSDU_size(ht: &hsr_ethhdr->hsr_tag, LSDU_size: lsdu_size);
319 hsr_ethhdr->hsr_tag.sequence_nr = htons(frame->sequence_nr);
320 hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
321 hsr_ethhdr->ethhdr.h_proto = htons(proto_version ?
322 ETH_P_HSR : ETH_P_PRP);
323 skb->protocol = hsr_ethhdr->ethhdr.h_proto;
324
325 return skb;
326}
327
328/* If the original frame was an HSR tagged frame, just clone it to be sent
329 * unchanged. Otherwise, create a private frame especially tagged for 'port'.
330 */
331struct sk_buff *hsr_create_tagged_frame(struct hsr_frame_info *frame,
332 struct hsr_port *port)
333{
334 unsigned char *dst, *src;
335 struct sk_buff *skb;
336 int movelen;
337
338 if (frame->skb_hsr) {
339 struct hsr_ethhdr *hsr_ethhdr =
340 (struct hsr_ethhdr *)skb_mac_header(skb: frame->skb_hsr);
341
342 /* set the lane id properly */
343 hsr_set_path_id(frame, hsr_ethhdr, port);
344 return skb_clone(skb: frame->skb_hsr, GFP_ATOMIC);
345 } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
346 return skb_clone(skb: frame->skb_std, GFP_ATOMIC);
347 }
348
349 /* Create the new skb with enough headroom to fit the HSR tag */
350 skb = __pskb_copy(skb: frame->skb_std,
351 headroom: skb_headroom(skb: frame->skb_std) + HSR_HLEN, GFP_ATOMIC);
352 if (!skb)
353 return NULL;
354 skb_reset_mac_header(skb);
355
356 if (skb->ip_summed == CHECKSUM_PARTIAL)
357 skb->csum_start += HSR_HLEN;
358
359 movelen = ETH_HLEN;
360 if (frame->is_vlan)
361 movelen += VLAN_HLEN;
362
363 src = skb_mac_header(skb);
364 dst = skb_push(skb, HSR_HLEN);
365 memmove(dst, src, movelen);
366 skb_reset_mac_header(skb);
367
368 /* skb_put_padto free skb on error and hsr_fill_tag returns NULL in
369 * that case
370 */
371 return hsr_fill_tag(skb, frame, port, proto_version: port->hsr->prot_version);
372}
373
374struct sk_buff *prp_create_tagged_frame(struct hsr_frame_info *frame,
375 struct hsr_port *port)
376{
377 struct sk_buff *skb;
378
379 if (frame->skb_prp) {
380 struct prp_rct *trailer = skb_get_PRP_rct(skb: frame->skb_prp);
381
382 if (trailer) {
383 prp_set_lan_id(trailer, port);
384 } else {
385 WARN_ONCE(!trailer, "errored PRP skb");
386 return NULL;
387 }
388 return skb_clone(skb: frame->skb_prp, GFP_ATOMIC);
389 } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
390 return skb_clone(skb: frame->skb_std, GFP_ATOMIC);
391 }
392
393 skb = skb_copy_expand(skb: frame->skb_std, newheadroom: skb_headroom(skb: frame->skb_std),
394 newtailroom: skb_tailroom(skb: frame->skb_std) + HSR_HLEN,
395 GFP_ATOMIC);
396 return prp_fill_rct(skb, frame, port);
397}
398
399static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev,
400 struct hsr_node *node_src)
401{
402 bool was_multicast_frame;
403 int res, recv_len;
404
405 was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST);
406 hsr_addr_subst_source(node: node_src, skb);
407 skb_pull(skb, ETH_HLEN);
408 recv_len = skb->len;
409 res = netif_rx(skb);
410 if (res == NET_RX_DROP) {
411 dev->stats.rx_dropped++;
412 } else {
413 dev->stats.rx_packets++;
414 dev->stats.rx_bytes += recv_len;
415 if (was_multicast_frame)
416 dev->stats.multicast++;
417 }
418}
419
420static int hsr_xmit(struct sk_buff *skb, struct hsr_port *port,
421 struct hsr_frame_info *frame)
422{
423 if (frame->port_rcv->type == HSR_PT_MASTER) {
424 hsr_addr_subst_dest(node_src: frame->node_src, skb, port);
425
426 /* Address substitution (IEC62439-3 pp 26, 50): replace mac
427 * address of outgoing frame with that of the outgoing slave's.
428 */
429 ether_addr_copy(dst: eth_hdr(skb)->h_source, src: port->dev->dev_addr);
430 }
431
432 /* When HSR node is used as RedBox - the frame received from HSR ring
433 * requires source MAC address (SA) replacement to one which can be
434 * recognized by SAN devices (otherwise, frames are dropped by switch)
435 */
436 if (port->type == HSR_PT_INTERLINK)
437 ether_addr_copy(dst: eth_hdr(skb)->h_source,
438 src: port->hsr->macaddress_redbox);
439
440 return dev_queue_xmit(skb);
441}
442
443bool prp_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
444{
445 return ((frame->port_rcv->type == HSR_PT_SLAVE_A &&
446 port->type == HSR_PT_SLAVE_B) ||
447 (frame->port_rcv->type == HSR_PT_SLAVE_B &&
448 port->type == HSR_PT_SLAVE_A));
449}
450
451bool hsr_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
452{
453 struct sk_buff *skb;
454
455 if (port->dev->features & NETIF_F_HW_HSR_FWD)
456 return prp_drop_frame(frame, port);
457
458 /* RedBox specific frames dropping policies
459 *
460 * Do not send HSR supervisory frames to SAN devices
461 */
462 if (frame->is_supervision && port->type == HSR_PT_INTERLINK)
463 return true;
464
465 /* Do not forward to other HSR port (A or B) unicast frames which
466 * are addressed to interlink port (and are in the ProxyNodeTable).
467 */
468 skb = frame->skb_hsr;
469 if (skb && prp_drop_frame(frame, port) &&
470 is_unicast_ether_addr(addr: eth_hdr(skb)->h_dest) &&
471 hsr_is_node_in_db(node_db: &port->hsr->proxy_node_db,
472 addr: eth_hdr(skb)->h_dest)) {
473 return true;
474 }
475
476 /* Do not forward to port C (Interlink) frames from nodes A and B
477 * if DA is in NodeTable.
478 */
479 if ((frame->port_rcv->type == HSR_PT_SLAVE_A ||
480 frame->port_rcv->type == HSR_PT_SLAVE_B) &&
481 port->type == HSR_PT_INTERLINK) {
482 skb = frame->skb_hsr;
483 if (skb && is_unicast_ether_addr(addr: eth_hdr(skb)->h_dest) &&
484 hsr_is_node_in_db(node_db: &port->hsr->node_db,
485 addr: eth_hdr(skb)->h_dest)) {
486 return true;
487 }
488 }
489
490 /* Do not forward to port A and B unicast frames received on the
491 * interlink port if it is addressed to one of nodes registered in
492 * the ProxyNodeTable.
493 */
494 if ((port->type == HSR_PT_SLAVE_A || port->type == HSR_PT_SLAVE_B) &&
495 frame->port_rcv->type == HSR_PT_INTERLINK) {
496 skb = frame->skb_std;
497 if (skb && is_unicast_ether_addr(addr: eth_hdr(skb)->h_dest) &&
498 hsr_is_node_in_db(node_db: &port->hsr->proxy_node_db,
499 addr: eth_hdr(skb)->h_dest)) {
500 return true;
501 }
502 }
503
504 return false;
505}
506
507/* Forward the frame through all devices except:
508 * - Back through the receiving device
509 * - If it's a HSR frame: through a device where it has passed before
510 * - if it's a PRP frame: through another PRP slave device (no bridge)
511 * - To the local HSR master only if the frame is directly addressed to it, or
512 * a non-supervision multicast or broadcast frame.
513 *
514 * HSR slave devices should insert a HSR tag into the frame, or forward the
515 * frame unchanged if it's already tagged. Interlink devices should strip HSR
516 * tags if they're of the non-HSR type (but only after duplicate discard). The
517 * master device always strips HSR tags.
518 */
519static void hsr_forward_do(struct hsr_frame_info *frame)
520{
521 struct hsr_port *port;
522 struct sk_buff *skb;
523 bool sent = false;
524
525 hsr_for_each_port(frame->port_rcv->hsr, port) {
526 struct hsr_priv *hsr = port->hsr;
527 /* Don't send frame back the way it came */
528 if (port == frame->port_rcv)
529 continue;
530
531 /* Don't deliver locally unless we should */
532 if (port->type == HSR_PT_MASTER && !frame->is_local_dest)
533 continue;
534
535 /* Deliver frames directly addressed to us to master only */
536 if (port->type != HSR_PT_MASTER && frame->is_local_exclusive)
537 continue;
538
539 /* If hardware duplicate generation is enabled, only send out
540 * one port.
541 */
542 if ((port->dev->features & NETIF_F_HW_HSR_DUP) && sent)
543 continue;
544
545 /* Don't send frame over port where it has been sent before.
546 * Also for SAN, this shouldn't be done.
547 */
548 if (!frame->is_from_san &&
549 hsr->proto_ops->register_frame_out &&
550 hsr->proto_ops->register_frame_out(port, frame))
551 continue;
552
553 if (frame->is_supervision && port->type == HSR_PT_MASTER &&
554 !frame->is_proxy_supervision) {
555 hsr_handle_sup_frame(frame);
556 continue;
557 }
558
559 /* Check if frame is to be dropped. Eg. for PRP no forward
560 * between ports, or sending HSR supervision to RedBox.
561 */
562 if (hsr->proto_ops->drop_frame &&
563 hsr->proto_ops->drop_frame(frame, port))
564 continue;
565
566 if (port->type == HSR_PT_SLAVE_A ||
567 port->type == HSR_PT_SLAVE_B)
568 skb = hsr->proto_ops->create_tagged_frame(frame, port);
569 else
570 skb = hsr->proto_ops->get_untagged_frame(frame, port);
571
572 if (!skb) {
573 frame->port_rcv->dev->stats.rx_dropped++;
574 continue;
575 }
576
577 skb->dev = port->dev;
578 if (port->type == HSR_PT_MASTER) {
579 hsr_deliver_master(skb, dev: port->dev, node_src: frame->node_src);
580 } else {
581 if (!hsr_xmit(skb, port, frame))
582 if (port->type == HSR_PT_SLAVE_A ||
583 port->type == HSR_PT_SLAVE_B)
584 sent = true;
585 }
586 }
587}
588
589static void check_local_dest(struct hsr_priv *hsr, struct sk_buff *skb,
590 struct hsr_frame_info *frame)
591{
592 if (hsr_addr_is_self(hsr, addr: eth_hdr(skb)->h_dest)) {
593 frame->is_local_exclusive = true;
594 skb->pkt_type = PACKET_HOST;
595 } else {
596 frame->is_local_exclusive = false;
597 }
598
599 if (skb->pkt_type == PACKET_HOST ||
600 skb->pkt_type == PACKET_MULTICAST ||
601 skb->pkt_type == PACKET_BROADCAST) {
602 frame->is_local_dest = true;
603 } else {
604 frame->is_local_dest = false;
605 }
606}
607
608static void handle_std_frame(struct sk_buff *skb,
609 struct hsr_frame_info *frame)
610{
611 struct hsr_port *port = frame->port_rcv;
612 struct hsr_priv *hsr = port->hsr;
613
614 frame->skb_hsr = NULL;
615 frame->skb_prp = NULL;
616 frame->skb_std = skb;
617
618 if (port->type != HSR_PT_MASTER)
619 frame->is_from_san = true;
620
621 if (port->type == HSR_PT_MASTER ||
622 port->type == HSR_PT_INTERLINK) {
623 /* Sequence nr for the master/interlink node */
624 lockdep_assert_held(&hsr->seqnr_lock);
625 frame->sequence_nr = hsr->sequence_nr;
626 hsr->sequence_nr++;
627 }
628}
629
630int hsr_fill_frame_info(__be16 proto, struct sk_buff *skb,
631 struct hsr_frame_info *frame)
632{
633 struct hsr_port *port = frame->port_rcv;
634 struct hsr_priv *hsr = port->hsr;
635
636 /* HSRv0 supervisory frames double as a tag so treat them as tagged. */
637 if ((!hsr->prot_version && proto == htons(ETH_P_PRP)) ||
638 proto == htons(ETH_P_HSR)) {
639 /* Check if skb contains hsr_ethhdr */
640 if (skb->mac_len < sizeof(struct hsr_ethhdr))
641 return -EINVAL;
642
643 /* HSR tagged frame :- Data or Supervision */
644 frame->skb_std = NULL;
645 frame->skb_prp = NULL;
646 frame->skb_hsr = skb;
647 frame->sequence_nr = hsr_get_skb_sequence_nr(skb);
648 return 0;
649 }
650
651 /* Standard frame or PRP from master port */
652 handle_std_frame(skb, frame);
653
654 return 0;
655}
656
657int prp_fill_frame_info(__be16 proto, struct sk_buff *skb,
658 struct hsr_frame_info *frame)
659{
660 /* Supervision frame */
661 struct prp_rct *rct = skb_get_PRP_rct(skb);
662
663 if (rct &&
664 prp_check_lsdu_size(skb, rct, is_sup: frame->is_supervision)) {
665 frame->skb_hsr = NULL;
666 frame->skb_std = NULL;
667 frame->skb_prp = skb;
668 frame->sequence_nr = prp_get_skb_sequence_nr(rct);
669 return 0;
670 }
671 handle_std_frame(skb, frame);
672
673 return 0;
674}
675
676static int fill_frame_info(struct hsr_frame_info *frame,
677 struct sk_buff *skb, struct hsr_port *port)
678{
679 struct hsr_priv *hsr = port->hsr;
680 struct hsr_vlan_ethhdr *vlan_hdr;
681 struct list_head *n_db;
682 struct ethhdr *ethhdr;
683 __be16 proto;
684 int ret;
685
686 /* Check if skb contains ethhdr */
687 if (skb->mac_len < sizeof(struct ethhdr))
688 return -EINVAL;
689
690 memset(frame, 0, sizeof(*frame));
691 frame->is_supervision = is_supervision_frame(hsr: port->hsr, skb);
692 if (frame->is_supervision && hsr->redbox)
693 frame->is_proxy_supervision =
694 is_proxy_supervision_frame(hsr: port->hsr, skb);
695
696 n_db = &hsr->node_db;
697 if (port->type == HSR_PT_INTERLINK)
698 n_db = &hsr->proxy_node_db;
699
700 frame->node_src = hsr_get_node(port, node_db: n_db, skb,
701 is_sup: frame->is_supervision, rx_port: port->type);
702 if (!frame->node_src)
703 return -1; /* Unknown node and !is_supervision, or no mem */
704
705 ethhdr = (struct ethhdr *)skb_mac_header(skb);
706 frame->is_vlan = false;
707 proto = ethhdr->h_proto;
708
709 if (proto == htons(ETH_P_8021Q))
710 frame->is_vlan = true;
711
712 if (frame->is_vlan) {
713 /* Note: skb->mac_len might be wrong here. */
714 if (!pskb_may_pull(skb,
715 len: skb_mac_offset(skb) +
716 offsetofend(struct hsr_vlan_ethhdr, vlanhdr)))
717 return -EINVAL;
718 vlan_hdr = (struct hsr_vlan_ethhdr *)skb_mac_header(skb);
719 proto = vlan_hdr->vlanhdr.h_vlan_encapsulated_proto;
720 }
721
722 frame->is_from_san = false;
723 frame->port_rcv = port;
724 ret = hsr->proto_ops->fill_frame_info(proto, skb, frame);
725 if (ret)
726 return ret;
727
728 check_local_dest(hsr: port->hsr, skb, frame);
729
730 return 0;
731}
732
733/* Must be called holding rcu read lock (because of the port parameter) */
734void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port)
735{
736 struct hsr_frame_info frame;
737
738 rcu_read_lock();
739 if (fill_frame_info(frame: &frame, skb, port) < 0)
740 goto out_drop;
741
742 hsr_register_frame_in(node: frame.node_src, port, sequence_nr: frame.sequence_nr);
743 hsr_forward_do(frame: &frame);
744 rcu_read_unlock();
745 /* Gets called for ingress frames as well as egress from master port.
746 * So check and increment stats for master port only here.
747 */
748 if (port->type == HSR_PT_MASTER || port->type == HSR_PT_INTERLINK) {
749 port->dev->stats.tx_packets++;
750 port->dev->stats.tx_bytes += skb->len;
751 }
752
753 kfree_skb(skb: frame.skb_hsr);
754 kfree_skb(skb: frame.skb_prp);
755 kfree_skb(skb: frame.skb_std);
756 return;
757
758out_drop:
759 rcu_read_unlock();
760 port->dev->stats.tx_dropped++;
761 kfree_skb(skb);
762}
763

source code of linux/net/hsr/hsr_forward.c