net/hsr/hsr_forward.c

   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
  18 struct 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  */
  35 static 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(eth_hdr->h_dest,
  48                               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, 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, 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, total_length))
  88                 return false;
  89         skb_pull(skb, total_length);
  90         hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
  91         skb_push(skb, 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, total_length))
 104                         return false;
 105
 106                 /* get next tlv */
 107                 skb_pull(skb, total_length);
 108                 hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
 109                 skb_push(skb, 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
 120 static 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, total_length + sizeof(struct hsr_sup_payload)))
 136                 return false;
 137
 138         skb_pull(skb, total_length);
 139         payload = (struct hsr_sup_payload *)skb->data;
 140         skb_push(skb, 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(&hsr->proxy_node_db,
 146                                  payload->macaddress_A);
 147 }
 148
 149 static 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_in, HSR_HLEN);
 157         skb = __pskb_copy(skb_in, skb_headroom(skb_in) - HSR_HLEN, GFP_ATOMIC);
 158         skb_push(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_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
 178 struct 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(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(frame->skb_std, GFP_ATOMIC);
 194 }
 195
 196 struct 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(frame->skb_prp,
 203                                  frame->skb_prp->len - HSR_HLEN);
 204                         frame->skb_std =
 205                                 __pskb_copy(frame->skb_prp,
 206                                             skb_headroom(frame->skb_prp),
 207                                             GFP_ATOMIC);
 208                 } else {
 209                         /* Unexpected */
 210                         WARN_ONCE(1, "%s:%d: Unexpected frame received (port_src %s)\n",
 211                                   __FILE__, __LINE__, port->dev->name);
 212                         return NULL;
 213                 }
 214         }
 215
 216         return skb_clone(frame->skb_std, GFP_ATOMIC);
 217 }
 218
 219 static void prp_set_lan_id(struct prp_rct *trailer,
 220                            struct hsr_port *port)
 221 {
 222         int lane_id;
 223
 224         if (port->type == HSR_PT_SLAVE_A)
 225                 lane_id = 0;
 226         else
 227                 lane_id = 1;
 228
 229         /* Add net_id in the upper 3 bits of lane_id */
 230         lane_id |= port->hsr->net_id;
 231         set_prp_lan_id(trailer, lane_id);
 232 }
 233
 234 /* Tailroom for PRP rct should have been created before calling this */
 235 static struct sk_buff *prp_fill_rct(struct sk_buff *skb,
 236                                     struct hsr_frame_info *frame,
 237                                     struct hsr_port *port)
 238 {
 239         struct prp_rct *trailer;
 240         int min_size = ETH_ZLEN;
 241         int lsdu_size;
 242
 243         if (!skb)
 244                 return skb;
 245
 246         if (frame->is_vlan)
 247                 min_size = VLAN_ETH_ZLEN;
 248
 249         if (skb_put_padto(skb, min_size))
 250                 return NULL;
 251
 252         trailer = (struct prp_rct *)skb_put(skb, HSR_HLEN);
 253         lsdu_size = skb->len - 14;
 254         if (frame->is_vlan)
 255                 lsdu_size -= 4;
 256         prp_set_lan_id(trailer, port);
 257         set_prp_LSDU_size(trailer, lsdu_size);
 258         trailer->sequence_nr = htons(frame->sequence_nr);
 259         trailer->PRP_suffix = htons(ETH_P_PRP);
 260         skb->protocol = eth_hdr(skb)->h_proto;
 261
 262         return skb;
 263 }
 264
 265 static void hsr_set_path_id(struct hsr_ethhdr *hsr_ethhdr,
 266                             struct hsr_port *port)
 267 {
 268         int path_id;
 269
 270         if (port->type == HSR_PT_SLAVE_A)
 271                 path_id = 0;
 272         else
 273                 path_id = 1;
 274
 275         set_hsr_tag_path(&hsr_ethhdr->hsr_tag, path_id);
 276 }
 277
 278 static struct sk_buff *hsr_fill_tag(struct sk_buff *skb,
 279                                     struct hsr_frame_info *frame,
 280                                     struct hsr_port *port, u8 proto_version)
 281 {
 282         struct hsr_ethhdr *hsr_ethhdr;
 283         int lsdu_size;
 284
 285         /* pad to minimum packet size which is 60 + 6 (HSR tag) */
 286         if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN))
 287                 return NULL;
 288
 289         lsdu_size = skb->len - 14;
 290         if (frame->is_vlan)
 291                 lsdu_size -= 4;
 292
 293         hsr_ethhdr = (struct hsr_ethhdr *)skb_mac_header(skb);
 294
 295         hsr_set_path_id(hsr_ethhdr, port);
 296         set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, lsdu_size);
 297         hsr_ethhdr->hsr_tag.sequence_nr = htons(frame->sequence_nr);
 298         hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
 299         hsr_ethhdr->ethhdr.h_proto = htons(proto_version ?
 300                         ETH_P_HSR : ETH_P_PRP);
 301         skb->protocol = hsr_ethhdr->ethhdr.h_proto;
 302
 303         return skb;
 304 }
 305
 306 /* If the original frame was an HSR tagged frame, just clone it to be sent
 307  * unchanged. Otherwise, create a private frame especially tagged for 'port'.
 308  */
 309 struct sk_buff *hsr_create_tagged_frame(struct hsr_frame_info *frame,
 310                                         struct hsr_port *port)
 311 {
 312         unsigned char *dst, *src;
 313         struct sk_buff *skb;
 314         int movelen;
 315
 316         if (frame->skb_hsr) {
 317                 struct hsr_ethhdr *hsr_ethhdr =
 318                         (struct hsr_ethhdr *)skb_mac_header(frame->skb_hsr);
 319
 320                 /* set the lane id properly */
 321                 hsr_set_path_id(hsr_ethhdr, port);
 322                 return skb_clone(frame->skb_hsr, GFP_ATOMIC);
 323         } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
 324                 return skb_clone(frame->skb_std, GFP_ATOMIC);
 325         }
 326
 327         /* Create the new skb with enough headroom to fit the HSR tag */
 328         skb = __pskb_copy(frame->skb_std,
 329                           skb_headroom(frame->skb_std) + HSR_HLEN, GFP_ATOMIC);
 330         if (!skb)
 331                 return NULL;
 332         skb_reset_mac_header(skb);
 333
 334         if (skb->ip_summed == CHECKSUM_PARTIAL)
 335                 skb->csum_start += HSR_HLEN;
 336
 337         movelen = ETH_HLEN;
 338         if (frame->is_vlan)
 339                 movelen += VLAN_HLEN;
 340
 341         src = skb_mac_header(skb);
 342         dst = skb_push(skb, HSR_HLEN);
 343         memmove(dst, src, movelen);
 344         skb_reset_mac_header(skb);
 345
 346         /* skb_put_padto free skb on error and hsr_fill_tag returns NULL in
 347          * that case
 348          */
 349         return hsr_fill_tag(skb, frame, port, port->hsr->prot_version);
 350 }
 351
 352 struct sk_buff *prp_create_tagged_frame(struct hsr_frame_info *frame,
 353                                         struct hsr_port *port)
 354 {
 355         struct sk_buff *skb;
 356
 357         if (frame->skb_prp) {
 358                 struct prp_rct *trailer = skb_get_PRP_rct(frame->skb_prp);
 359
 360                 if (trailer) {
 361                         prp_set_lan_id(trailer, port);
 362                 } else {
 363                         WARN_ONCE(!trailer, "errored PRP skb");
 364                         return NULL;
 365                 }
 366                 return skb_clone(frame->skb_prp, GFP_ATOMIC);
 367         } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
 368                 return skb_clone(frame->skb_std, GFP_ATOMIC);
 369         }
 370
 371         skb = skb_copy_expand(frame->skb_std, 0,
 372                               skb_tailroom(frame->skb_std) + HSR_HLEN,
 373                               GFP_ATOMIC);
 374         return prp_fill_rct(skb, frame, port);
 375 }
 376
 377 static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev,
 378                                struct hsr_node *node_src)
 379 {
 380         bool was_multicast_frame;
 381         int res, recv_len;
 382
 383         was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST);
 384         hsr_addr_subst_source(node_src, skb);
 385         skb_pull(skb, ETH_HLEN);
 386         recv_len = skb->len;
 387         res = netif_rx(skb);
 388         if (res == NET_RX_DROP) {
 389                 dev->stats.rx_dropped++;
 390         } else {
 391                 dev->stats.rx_packets++;
 392                 dev->stats.rx_bytes += recv_len;
 393                 if (was_multicast_frame)
 394                         dev->stats.multicast++;
 395         }
 396 }
 397
 398 static int hsr_xmit(struct sk_buff *skb, struct hsr_port *port,
 399                     struct hsr_frame_info *frame)
 400 {
 401         if (frame->port_rcv->type == HSR_PT_MASTER) {
 402                 hsr_addr_subst_dest(frame->node_src, skb, port);
 403
 404                 /* Address substitution (IEC62439-3 pp 26, 50): replace mac
 405                  * address of outgoing frame with that of the outgoing slave's.
 406                  */
 407                 ether_addr_copy(eth_hdr(skb)->h_source, port->dev->dev_addr);
 408         }
 409
 410         /* When HSR node is used as RedBox - the frame received from HSR ring
 411          * requires source MAC address (SA) replacement to one which can be
 412          * recognized by SAN devices (otherwise, frames are dropped by switch)
 413          */
 414         if (port->type == HSR_PT_INTERLINK)
 415                 ether_addr_copy(eth_hdr(skb)->h_source,
 416                                 port->hsr->macaddress_redbox);
 417
 418         return dev_queue_xmit(skb);
 419 }
 420
 421 bool prp_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
 422 {
 423         return ((frame->port_rcv->type == HSR_PT_SLAVE_A &&
 424                  port->type == HSR_PT_SLAVE_B) ||
 425                 (frame->port_rcv->type == HSR_PT_SLAVE_B &&
 426                  port->type == HSR_PT_SLAVE_A));
 427 }
 428
 429 bool hsr_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
 430 {
 431         struct sk_buff *skb;
 432
 433         if (port->dev->features & NETIF_F_HW_HSR_FWD)
 434                 return prp_drop_frame(frame, port);
 435
 436         /* RedBox specific frames dropping policies
 437          *
 438          * Do not send HSR supervisory frames to SAN devices
 439          */
 440         if (frame->is_supervision && port->type == HSR_PT_INTERLINK)
 441                 return true;
 442
 443         /* Do not forward to other HSR port (A or B) unicast frames which
 444          * are addressed to interlink port (and are in the ProxyNodeTable).
 445          */
 446         skb = frame->skb_hsr;
 447         if (skb && prp_drop_frame(frame, port) &&
 448             is_unicast_ether_addr(eth_hdr(skb)->h_dest) &&
 449             hsr_is_node_in_db(&port->hsr->proxy_node_db,
 450                               eth_hdr(skb)->h_dest)) {
 451                 return true;
 452         }
 453
 454         /* Do not forward to port C (Interlink) frames from nodes A and B
 455          * if DA is in NodeTable.
 456          */
 457         if ((frame->port_rcv->type == HSR_PT_SLAVE_A ||
 458              frame->port_rcv->type == HSR_PT_SLAVE_B) &&
 459             port->type == HSR_PT_INTERLINK) {
 460                 skb = frame->skb_hsr;
 461                 if (skb && is_unicast_ether_addr(eth_hdr(skb)->h_dest) &&
 462                     hsr_is_node_in_db(&port->hsr->node_db,
 463                                       eth_hdr(skb)->h_dest)) {
 464                         return true;
 465                 }
 466         }
 467
 468         /* Do not forward to port A and B unicast frames received on the
 469          * interlink port if it is addressed to one of nodes registered in
 470          * the ProxyNodeTable.
 471          */
 472         if ((port->type == HSR_PT_SLAVE_A || port->type == HSR_PT_SLAVE_B) &&
 473             frame->port_rcv->type == HSR_PT_INTERLINK) {
 474                 skb = frame->skb_std;
 475                 if (skb && is_unicast_ether_addr(eth_hdr(skb)->h_dest) &&
 476                     hsr_is_node_in_db(&port->hsr->proxy_node_db,
 477                                       eth_hdr(skb)->h_dest)) {
 478                         return true;
 479                 }
 480         }
 481
 482         return false;
 483 }
 484
 485 /* Forward the frame through all devices except:
 486  * - Back through the receiving device
 487  * - If it's a HSR frame: through a device where it has passed before
 488  * - if it's a PRP frame: through another PRP slave device (no bridge)
 489  * - To the local HSR master only if the frame is directly addressed to it, or
 490  *   a non-supervision multicast or broadcast frame.
 491  *
 492  * HSR slave devices should insert a HSR tag into the frame, or forward the
 493  * frame unchanged if it's already tagged. Interlink devices should strip HSR
 494  * tags if they're of the non-HSR type (but only after duplicate discard). The
 495  * master device always strips HSR tags.
 496  */
 497 static void hsr_forward_do(struct hsr_frame_info *frame)
 498 {
 499         struct hsr_port *port;
 500         struct sk_buff *skb;
 501         bool sent = false;
 502
 503         hsr_for_each_port(frame->port_rcv->hsr, port) {
 504                 struct hsr_priv *hsr = port->hsr;
 505                 /* Don't send frame back the way it came */
 506                 if (port == frame->port_rcv)
 507                         continue;
 508
 509                 /* Don't deliver locally unless we should */
 510                 if (port->type == HSR_PT_MASTER && !frame->is_local_dest)
 511                         continue;
 512
 513                 /* Deliver frames directly addressed to us to master only */
 514                 if (port->type != HSR_PT_MASTER && frame->is_local_exclusive)
 515                         continue;
 516
 517                 /* If hardware duplicate generation is enabled, only send out
 518                  * one port.
 519                  */
 520                 if ((port->dev->features & NETIF_F_HW_HSR_DUP) && sent)
 521                         continue;
 522
 523                 /* Don't send frame over port where it has been sent before.
 524                  * Also for SAN, this shouldn't be done.
 525                  */
 526                 if (!frame->is_from_san &&
 527                     hsr_register_frame_out(port, frame->node_src,
 528                                            frame->sequence_nr))
 529                         continue;
 530
 531                 if (frame->is_supervision && port->type == HSR_PT_MASTER &&
 532                     !frame->is_proxy_supervision) {
 533                         hsr_handle_sup_frame(frame);
 534                         continue;
 535                 }
 536
 537                 /* Check if frame is to be dropped. Eg. for PRP no forward
 538                  * between ports, or sending HSR supervision to RedBox.
 539                  */
 540                 if (hsr->proto_ops->drop_frame &&
 541                     hsr->proto_ops->drop_frame(frame, port))
 542                         continue;
 543
 544                 if (port->type == HSR_PT_SLAVE_A ||
 545                     port->type == HSR_PT_SLAVE_B)
 546                         skb = hsr->proto_ops->create_tagged_frame(frame, port);
 547                 else
 548                         skb = hsr->proto_ops->get_untagged_frame(frame, port);
 549
 550                 if (!skb) {
 551                         frame->port_rcv->dev->stats.rx_dropped++;
 552                         continue;
 553                 }
 554
 555                 skb->dev = port->dev;
 556                 if (port->type == HSR_PT_MASTER) {
 557                         hsr_deliver_master(skb, port->dev, frame->node_src);
 558                 } else {
 559                         if (!hsr_xmit(skb, port, frame))
 560                                 if (port->type == HSR_PT_SLAVE_A ||
 561                                     port->type == HSR_PT_SLAVE_B)
 562                                         sent = true;
 563                 }
 564         }
 565 }
 566
 567 static void check_local_dest(struct hsr_priv *hsr, struct sk_buff *skb,
 568                              struct hsr_frame_info *frame)
 569 {
 570         if (hsr_addr_is_self(hsr, eth_hdr(skb)->h_dest)) {
 571                 frame->is_local_exclusive = true;
 572                 skb->pkt_type = PACKET_HOST;
 573         } else {
 574                 frame->is_local_exclusive = false;
 575         }
 576
 577         if (skb->pkt_type == PACKET_HOST ||
 578             skb->pkt_type == PACKET_MULTICAST ||
 579             skb->pkt_type == PACKET_BROADCAST) {
 580                 frame->is_local_dest = true;
 581         } else {
 582                 frame->is_local_dest = false;
 583         }
 584 }
 585
 586 static void handle_std_frame(struct sk_buff *skb,
 587                              struct hsr_frame_info *frame)
 588 {
 589         struct hsr_port *port = frame->port_rcv;
 590         struct hsr_priv *hsr = port->hsr;
 591
 592         frame->skb_hsr = NULL;
 593         frame->skb_prp = NULL;
 594         frame->skb_std = skb;
 595
 596         if (port->type != HSR_PT_MASTER)
 597                 frame->is_from_san = true;
 598
 599         if (port->type == HSR_PT_MASTER ||
 600             port->type == HSR_PT_INTERLINK) {
 601                 /* Sequence nr for the master/interlink node */
 602                 lockdep_assert_held(&hsr->seqnr_lock);
 603                 frame->sequence_nr = hsr->sequence_nr;
 604                 hsr->sequence_nr++;
 605         }
 606 }
 607
 608 int hsr_fill_frame_info(__be16 proto, 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         /* HSRv0 supervisory frames double as a tag so treat them as tagged. */
 615         if ((!hsr->prot_version && proto == htons(ETH_P_PRP)) ||
 616             proto == htons(ETH_P_HSR)) {
 617                 /* Check if skb contains hsr_ethhdr */
 618                 if (skb->mac_len < sizeof(struct hsr_ethhdr))
 619                         return -EINVAL;
 620
 621                 /* HSR tagged frame :- Data or Supervision */
 622                 frame->skb_std = NULL;
 623                 frame->skb_prp = NULL;
 624                 frame->skb_hsr = skb;
 625                 frame->sequence_nr = hsr_get_skb_sequence_nr(skb);
 626                 return 0;
 627         }
 628
 629         /* Standard frame or PRP from master port */
 630         handle_std_frame(skb, frame);
 631
 632         return 0;
 633 }
 634
 635 int prp_fill_frame_info(__be16 proto, struct sk_buff *skb,
 636                         struct hsr_frame_info *frame)
 637 {
 638         /* Supervision frame */
 639         struct prp_rct *rct = skb_get_PRP_rct(skb);
 640
 641         if (rct &&
 642             prp_check_lsdu_size(skb, rct, frame->is_supervision)) {
 643                 frame->skb_hsr = NULL;
 644                 frame->skb_std = NULL;
 645                 frame->skb_prp = skb;
 646                 frame->sequence_nr = prp_get_skb_sequence_nr(rct);
 647                 return 0;
 648         }
 649         handle_std_frame(skb, frame);
 650
 651         return 0;
 652 }
 653
 654 static int fill_frame_info(struct hsr_frame_info *frame,
 655                            struct sk_buff *skb, struct hsr_port *port)
 656 {
 657         struct hsr_priv *hsr = port->hsr;
 658         struct hsr_vlan_ethhdr *vlan_hdr;
 659         struct list_head *n_db;
 660         struct ethhdr *ethhdr;
 661         __be16 proto;
 662         int ret;
 663
 664         /* Check if skb contains ethhdr */
 665         if (skb->mac_len < sizeof(struct ethhdr))
 666                 return -EINVAL;
 667
 668         memset(frame, 0, sizeof(*frame));
 669         frame->is_supervision = is_supervision_frame(port->hsr, skb);
 670         if (frame->is_supervision && hsr->redbox)
 671                 frame->is_proxy_supervision =
 672                         is_proxy_supervision_frame(port->hsr, skb);
 673
 674         n_db = &hsr->node_db;
 675         if (port->type == HSR_PT_INTERLINK)
 676                 n_db = &hsr->proxy_node_db;
 677
 678         frame->node_src = hsr_get_node(port, n_db, skb,
 679                                        frame->is_supervision, port->type);
 680         if (!frame->node_src)
 681                 return -1; /* Unknown node and !is_supervision, or no mem */
 682
 683         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 684         frame->is_vlan = false;
 685         proto = ethhdr->h_proto;
 686
 687         if (proto == htons(ETH_P_8021Q))
 688                 frame->is_vlan = true;
 689
 690         if (frame->is_vlan) {
 691                 vlan_hdr = (struct hsr_vlan_ethhdr *)ethhdr;
 692                 proto = vlan_hdr->vlanhdr.h_vlan_encapsulated_proto;
 693                 /* FIXME: */
 694                 netdev_warn_once(skb->dev, "VLAN not yet supported");
 695                 return -EINVAL;
 696         }
 697
 698         frame->is_from_san = false;
 699         frame->port_rcv = port;
 700         ret = hsr->proto_ops->fill_frame_info(proto, skb, frame);
 701         if (ret)
 702                 return ret;
 703
 704         check_local_dest(port->hsr, skb, frame);
 705
 706         return 0;
 707 }
 708
 709 /* Must be called holding rcu read lock (because of the port parameter) */
 710 void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port)
 711 {
 712         struct hsr_frame_info frame;
 713
 714         rcu_read_lock();
 715         if (fill_frame_info(&frame, skb, port) < 0)
 716                 goto out_drop;
 717
 718         hsr_register_frame_in(frame.node_src, port, frame.sequence_nr);
 719         hsr_forward_do(&frame);
 720         rcu_read_unlock();
 721         /* Gets called for ingress frames as well as egress from master port.
 722          * So check and increment stats for master port only here.
 723          */
 724         if (port->type == HSR_PT_MASTER || port->type == HSR_PT_INTERLINK) {
 725                 port->dev->stats.tx_packets++;
 726                 port->dev->stats.tx_bytes += skb->len;
 727         }
 728
 729         kfree_skb(frame.skb_hsr);
 730         kfree_skb(frame.skb_prp);
 731         kfree_skb(frame.skb_std);
 732         return;
 733
 734 out_drop:
 735         rcu_read_unlock();
 736         port->dev->stats.tx_dropped++;
 737         kfree_skb(skb);
 738 }