1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright 2011-2014 Autronica Fire and Security AS
5 * 2011-2014 Arvid Brodin, arvid.brodin@alten.se
7 * Frame router for HSR and PRP.
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>
16 #include "hsr_framereg.h"
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.
25 * Or not - resetting the counter and bridging the frame would create a
26 * loop, unfortunately.
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.
32 * 3) Allow different MAC addresses for the two slave interfaces, using the
35 static bool is_supervision_frame(struct hsr_priv *hsr, struct sk_buff *skb)
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;
43 WARN_ON_ONCE(!skb_mac_header_was_set(skb));
44 eth_hdr = (struct ethhdr *)skb_mac_header(skb);
47 if (!ether_addr_equal(eth_hdr->h_dest,
48 hsr->sup_multicast_addr))
51 /* Correct ether type?. */
52 if (!(eth_hdr->h_proto == htons(ETH_P_PRP) ||
53 eth_hdr->h_proto == htons(ETH_P_HSR)))
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, total_length))
62 hsr_V1_hdr = (struct hsrv1_ethhdr_sp *)skb_mac_header(skb);
63 if (hsr_V1_hdr->hsr.encap_proto != htons(ETH_P_PRP))
66 hsr_sup_tag = &hsr_V1_hdr->hsr_sup;
68 total_length = sizeof(struct hsrv0_ethhdr_sp);
69 if (!pskb_may_pull(skb, total_length))
73 &((struct hsrv0_ethhdr_sp *)skb_mac_header(skb))->hsr_sup;
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)
81 if (hsr_sup_tag->tlv.HSR_TLV_length != 12 &&
82 hsr_sup_tag->tlv.HSR_TLV_length != sizeof(struct hsr_sup_payload))
86 total_length += sizeof(struct hsr_sup_tlv) + hsr_sup_tag->tlv.HSR_TLV_length;
87 if (!pskb_may_pull(skb, total_length))
89 skb_pull(skb, total_length);
90 hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
91 skb_push(skb, total_length);
93 /* if this is a redbox supervision frame we need to verify
94 * that more data is available
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))
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, total_length))
107 skb_pull(skb, total_length);
108 hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
109 skb_push(skb, total_length);
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)
120 static struct sk_buff *create_stripped_skb_hsr(struct sk_buff *skb_in,
121 struct hsr_frame_info *frame)
125 unsigned char *dst, *src;
127 skb_pull(skb_in, HSR_HLEN);
128 skb = __pskb_copy(skb_in, skb_headroom(skb_in) - HSR_HLEN, GFP_ATOMIC);
129 skb_push(skb_in, HSR_HLEN);
133 skb_reset_mac_header(skb);
135 if (skb->ip_summed == CHECKSUM_PARTIAL)
136 skb->csum_start -= HSR_HLEN;
138 copylen = 2 * ETH_ALEN;
140 copylen += VLAN_HLEN;
141 src = skb_mac_header(skb_in);
142 dst = skb_mac_header(skb);
143 memcpy(dst, src, copylen);
145 skb->protocol = eth_hdr(skb)->h_proto;
149 struct sk_buff *hsr_get_untagged_frame(struct hsr_frame_info *frame,
150 struct hsr_port *port)
152 if (!frame->skb_std) {
153 if (frame->skb_hsr) {
155 create_stripped_skb_hsr(frame->skb_hsr, frame);
158 WARN_ONCE(1, "%s:%d: Unexpected frame received (port_src %s)\n",
159 __FILE__, __LINE__, port->dev->name);
164 return skb_clone(frame->skb_std, GFP_ATOMIC);
167 struct sk_buff *prp_get_untagged_frame(struct hsr_frame_info *frame,
168 struct hsr_port *port)
170 if (!frame->skb_std) {
171 if (frame->skb_prp) {
172 /* trim the skb by len - HSR_HLEN to exclude RCT */
173 skb_trim(frame->skb_prp,
174 frame->skb_prp->len - HSR_HLEN);
176 __pskb_copy(frame->skb_prp,
177 skb_headroom(frame->skb_prp),
181 WARN_ONCE(1, "%s:%d: Unexpected frame received (port_src %s)\n",
182 __FILE__, __LINE__, port->dev->name);
187 return skb_clone(frame->skb_std, GFP_ATOMIC);
190 static void prp_set_lan_id(struct prp_rct *trailer,
191 struct hsr_port *port)
195 if (port->type == HSR_PT_SLAVE_A)
200 /* Add net_id in the upper 3 bits of lane_id */
201 lane_id |= port->hsr->net_id;
202 set_prp_lan_id(trailer, lane_id);
205 /* Tailroom for PRP rct should have been created before calling this */
206 static struct sk_buff *prp_fill_rct(struct sk_buff *skb,
207 struct hsr_frame_info *frame,
208 struct hsr_port *port)
210 struct prp_rct *trailer;
211 int min_size = ETH_ZLEN;
218 min_size = VLAN_ETH_ZLEN;
220 if (skb_put_padto(skb, min_size))
223 trailer = (struct prp_rct *)skb_put(skb, HSR_HLEN);
224 lsdu_size = skb->len - 14;
227 prp_set_lan_id(trailer, port);
228 set_prp_LSDU_size(trailer, lsdu_size);
229 trailer->sequence_nr = htons(frame->sequence_nr);
230 trailer->PRP_suffix = htons(ETH_P_PRP);
231 skb->protocol = eth_hdr(skb)->h_proto;
236 static void hsr_set_path_id(struct hsr_ethhdr *hsr_ethhdr,
237 struct hsr_port *port)
241 if (port->type == HSR_PT_SLAVE_A)
246 set_hsr_tag_path(&hsr_ethhdr->hsr_tag, path_id);
249 static struct sk_buff *hsr_fill_tag(struct sk_buff *skb,
250 struct hsr_frame_info *frame,
251 struct hsr_port *port, u8 proto_version)
253 struct hsr_ethhdr *hsr_ethhdr;
256 /* pad to minimum packet size which is 60 + 6 (HSR tag) */
257 if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN))
260 lsdu_size = skb->len - 14;
264 hsr_ethhdr = (struct hsr_ethhdr *)skb_mac_header(skb);
266 hsr_set_path_id(hsr_ethhdr, port);
267 set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, lsdu_size);
268 hsr_ethhdr->hsr_tag.sequence_nr = htons(frame->sequence_nr);
269 hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
270 hsr_ethhdr->ethhdr.h_proto = htons(proto_version ?
271 ETH_P_HSR : ETH_P_PRP);
272 skb->protocol = hsr_ethhdr->ethhdr.h_proto;
277 /* If the original frame was an HSR tagged frame, just clone it to be sent
278 * unchanged. Otherwise, create a private frame especially tagged for 'port'.
280 struct sk_buff *hsr_create_tagged_frame(struct hsr_frame_info *frame,
281 struct hsr_port *port)
283 unsigned char *dst, *src;
287 if (frame->skb_hsr) {
288 struct hsr_ethhdr *hsr_ethhdr =
289 (struct hsr_ethhdr *)skb_mac_header(frame->skb_hsr);
291 /* set the lane id properly */
292 hsr_set_path_id(hsr_ethhdr, port);
293 return skb_clone(frame->skb_hsr, GFP_ATOMIC);
294 } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
295 return skb_clone(frame->skb_std, GFP_ATOMIC);
298 /* Create the new skb with enough headroom to fit the HSR tag */
299 skb = __pskb_copy(frame->skb_std,
300 skb_headroom(frame->skb_std) + HSR_HLEN, GFP_ATOMIC);
303 skb_reset_mac_header(skb);
305 if (skb->ip_summed == CHECKSUM_PARTIAL)
306 skb->csum_start += HSR_HLEN;
310 movelen += VLAN_HLEN;
312 src = skb_mac_header(skb);
313 dst = skb_push(skb, HSR_HLEN);
314 memmove(dst, src, movelen);
315 skb_reset_mac_header(skb);
317 /* skb_put_padto free skb on error and hsr_fill_tag returns NULL in
320 return hsr_fill_tag(skb, frame, port, port->hsr->prot_version);
323 struct sk_buff *prp_create_tagged_frame(struct hsr_frame_info *frame,
324 struct hsr_port *port)
328 if (frame->skb_prp) {
329 struct prp_rct *trailer = skb_get_PRP_rct(frame->skb_prp);
332 prp_set_lan_id(trailer, port);
334 WARN_ONCE(!trailer, "errored PRP skb");
337 return skb_clone(frame->skb_prp, GFP_ATOMIC);
338 } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
339 return skb_clone(frame->skb_std, GFP_ATOMIC);
342 skb = skb_copy_expand(frame->skb_std, 0,
343 skb_tailroom(frame->skb_std) + HSR_HLEN,
345 prp_fill_rct(skb, frame, port);
350 static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev,
351 struct hsr_node *node_src)
353 bool was_multicast_frame;
356 was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST);
357 hsr_addr_subst_source(node_src, skb);
358 skb_pull(skb, ETH_HLEN);
360 if (res == NET_RX_DROP) {
361 dev->stats.rx_dropped++;
363 dev->stats.rx_packets++;
364 dev->stats.rx_bytes += skb->len;
365 if (was_multicast_frame)
366 dev->stats.multicast++;
370 static int hsr_xmit(struct sk_buff *skb, struct hsr_port *port,
371 struct hsr_frame_info *frame)
373 if (frame->port_rcv->type == HSR_PT_MASTER) {
374 hsr_addr_subst_dest(frame->node_src, skb, port);
376 /* Address substitution (IEC62439-3 pp 26, 50): replace mac
377 * address of outgoing frame with that of the outgoing slave's.
379 ether_addr_copy(eth_hdr(skb)->h_source, port->dev->dev_addr);
381 return dev_queue_xmit(skb);
384 bool prp_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
386 return ((frame->port_rcv->type == HSR_PT_SLAVE_A &&
387 port->type == HSR_PT_SLAVE_B) ||
388 (frame->port_rcv->type == HSR_PT_SLAVE_B &&
389 port->type == HSR_PT_SLAVE_A));
392 bool hsr_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
394 if (port->dev->features & NETIF_F_HW_HSR_FWD)
395 return prp_drop_frame(frame, port);
400 /* Forward the frame through all devices except:
401 * - Back through the receiving device
402 * - If it's a HSR frame: through a device where it has passed before
403 * - if it's a PRP frame: through another PRP slave device (no bridge)
404 * - To the local HSR master only if the frame is directly addressed to it, or
405 * a non-supervision multicast or broadcast frame.
407 * HSR slave devices should insert a HSR tag into the frame, or forward the
408 * frame unchanged if it's already tagged. Interlink devices should strip HSR
409 * tags if they're of the non-HSR type (but only after duplicate discard). The
410 * master device always strips HSR tags.
412 static void hsr_forward_do(struct hsr_frame_info *frame)
414 struct hsr_port *port;
418 hsr_for_each_port(frame->port_rcv->hsr, port) {
419 struct hsr_priv *hsr = port->hsr;
420 /* Don't send frame back the way it came */
421 if (port == frame->port_rcv)
424 /* Don't deliver locally unless we should */
425 if (port->type == HSR_PT_MASTER && !frame->is_local_dest)
428 /* Deliver frames directly addressed to us to master only */
429 if (port->type != HSR_PT_MASTER && frame->is_local_exclusive)
432 /* If hardware duplicate generation is enabled, only send out
435 if ((port->dev->features & NETIF_F_HW_HSR_DUP) && sent)
438 /* Don't send frame over port where it has been sent before.
439 * Also fro SAN, this shouldn't be done.
441 if (!frame->is_from_san &&
442 hsr_register_frame_out(port, frame->node_src,
446 if (frame->is_supervision && port->type == HSR_PT_MASTER) {
447 hsr_handle_sup_frame(frame);
451 /* Check if frame is to be dropped. Eg. for PRP no forward
454 if (hsr->proto_ops->drop_frame &&
455 hsr->proto_ops->drop_frame(frame, port))
458 if (port->type != HSR_PT_MASTER)
459 skb = hsr->proto_ops->create_tagged_frame(frame, port);
461 skb = hsr->proto_ops->get_untagged_frame(frame, port);
464 frame->port_rcv->dev->stats.rx_dropped++;
468 skb->dev = port->dev;
469 if (port->type == HSR_PT_MASTER) {
470 hsr_deliver_master(skb, port->dev, frame->node_src);
472 if (!hsr_xmit(skb, port, frame))
478 static void check_local_dest(struct hsr_priv *hsr, struct sk_buff *skb,
479 struct hsr_frame_info *frame)
481 if (hsr_addr_is_self(hsr, eth_hdr(skb)->h_dest)) {
482 frame->is_local_exclusive = true;
483 skb->pkt_type = PACKET_HOST;
485 frame->is_local_exclusive = false;
488 if (skb->pkt_type == PACKET_HOST ||
489 skb->pkt_type == PACKET_MULTICAST ||
490 skb->pkt_type == PACKET_BROADCAST) {
491 frame->is_local_dest = true;
493 frame->is_local_dest = false;
497 static void handle_std_frame(struct sk_buff *skb,
498 struct hsr_frame_info *frame)
500 struct hsr_port *port = frame->port_rcv;
501 struct hsr_priv *hsr = port->hsr;
502 unsigned long irqflags;
504 frame->skb_hsr = NULL;
505 frame->skb_prp = NULL;
506 frame->skb_std = skb;
508 if (port->type != HSR_PT_MASTER) {
509 frame->is_from_san = true;
511 /* Sequence nr for the master node */
512 spin_lock_irqsave(&hsr->seqnr_lock, irqflags);
513 frame->sequence_nr = hsr->sequence_nr;
515 spin_unlock_irqrestore(&hsr->seqnr_lock, irqflags);
519 int hsr_fill_frame_info(__be16 proto, struct sk_buff *skb,
520 struct hsr_frame_info *frame)
522 struct hsr_port *port = frame->port_rcv;
523 struct hsr_priv *hsr = port->hsr;
525 /* HSRv0 supervisory frames double as a tag so treat them as tagged. */
526 if ((!hsr->prot_version && proto == htons(ETH_P_PRP)) ||
527 proto == htons(ETH_P_HSR)) {
528 /* Check if skb contains hsr_ethhdr */
529 if (skb->mac_len < sizeof(struct hsr_ethhdr))
532 /* HSR tagged frame :- Data or Supervision */
533 frame->skb_std = NULL;
534 frame->skb_prp = NULL;
535 frame->skb_hsr = skb;
536 frame->sequence_nr = hsr_get_skb_sequence_nr(skb);
540 /* Standard frame or PRP from master port */
541 handle_std_frame(skb, frame);
546 int prp_fill_frame_info(__be16 proto, struct sk_buff *skb,
547 struct hsr_frame_info *frame)
549 /* Supervision frame */
550 struct prp_rct *rct = skb_get_PRP_rct(skb);
553 prp_check_lsdu_size(skb, rct, frame->is_supervision)) {
554 frame->skb_hsr = NULL;
555 frame->skb_std = NULL;
556 frame->skb_prp = skb;
557 frame->sequence_nr = prp_get_skb_sequence_nr(rct);
560 handle_std_frame(skb, frame);
565 static int fill_frame_info(struct hsr_frame_info *frame,
566 struct sk_buff *skb, struct hsr_port *port)
568 struct hsr_priv *hsr = port->hsr;
569 struct hsr_vlan_ethhdr *vlan_hdr;
570 struct ethhdr *ethhdr;
575 /* Check if skb contains ethhdr */
576 if (skb->mac_len < sizeof(struct ethhdr))
579 memset(frame, 0, sizeof(*frame));
581 ethhdr = (struct ethhdr *)skb_mac_header(skb);
582 hash = hsr_mac_hash(port->hsr, ethhdr->h_source);
583 frame->is_supervision = is_supervision_frame(port->hsr, skb);
584 frame->node_src = hsr_get_node(port, &hsr->node_db[hash], skb,
585 frame->is_supervision,
587 if (!frame->node_src)
588 return -1; /* Unknown node and !is_supervision, or no mem */
590 frame->is_vlan = false;
591 proto = ethhdr->h_proto;
593 if (proto == htons(ETH_P_8021Q))
594 frame->is_vlan = true;
596 if (frame->is_vlan) {
597 vlan_hdr = (struct hsr_vlan_ethhdr *)ethhdr;
598 proto = vlan_hdr->vlanhdr.h_vlan_encapsulated_proto;
600 netdev_warn_once(skb->dev, "VLAN not yet supported");
603 frame->is_from_san = false;
604 frame->port_rcv = port;
605 ret = hsr->proto_ops->fill_frame_info(proto, skb, frame);
609 check_local_dest(port->hsr, skb, frame);
614 /* Must be called holding rcu read lock (because of the port parameter) */
615 void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port)
617 struct hsr_frame_info frame;
619 if (fill_frame_info(&frame, skb, port) < 0)
622 hsr_register_frame_in(frame.node_src, port, frame.sequence_nr);
623 hsr_forward_do(&frame);
624 /* Gets called for ingress frames as well as egress from master port.
625 * So check and increment stats for master port only here.
627 if (port->type == HSR_PT_MASTER) {
628 port->dev->stats.tx_packets++;
629 port->dev->stats.tx_bytes += skb->len;
632 kfree_skb(frame.skb_hsr);
633 kfree_skb(frame.skb_prp);
634 kfree_skb(frame.skb_std);
638 port->dev->stats.tx_dropped++;