1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * VLAN An implementation of 802.1Q VLAN tagging. 4 * 5 * Authors: Ben Greear <greearb@candelatech.com> 6 */ 7 #ifndef _LINUX_IF_VLAN_H_ 8 #define _LINUX_IF_VLAN_H_ 9 10 #include <linux/netdevice.h> 11 #include <linux/etherdevice.h> 12 #include <linux/rtnetlink.h> 13 #include <linux/bug.h> 14 #include <uapi/linux/if_vlan.h> 15 16 #define VLAN_HLEN 4 /* The additional bytes required by VLAN 17 * (in addition to the Ethernet header) 18 */ 19 #define VLAN_ETH_HLEN 18 /* Total octets in header. */ 20 #define VLAN_ETH_ZLEN 64 /* Min. octets in frame sans FCS */ 21 22 /* 23 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan 24 */ 25 #define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */ 26 #define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */ 27 28 #define VLAN_MAX_DEPTH 8 /* Max. number of nested VLAN tags parsed */ 29 30 /* 31 * struct vlan_hdr - vlan header 32 * @h_vlan_TCI: priority and VLAN ID 33 * @h_vlan_encapsulated_proto: packet type ID or len 34 */ 35 struct vlan_hdr { 36 __be16 h_vlan_TCI; 37 __be16 h_vlan_encapsulated_proto; 38 }; 39 40 /** 41 * struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr) 42 * @h_dest: destination ethernet address 43 * @h_source: source ethernet address 44 * @h_vlan_proto: ethernet protocol 45 * @h_vlan_TCI: priority and VLAN ID 46 * @h_vlan_encapsulated_proto: packet type ID or len 47 */ 48 struct vlan_ethhdr { 49 unsigned char h_dest[ETH_ALEN]; 50 unsigned char h_source[ETH_ALEN]; 51 __be16 h_vlan_proto; 52 __be16 h_vlan_TCI; 53 __be16 h_vlan_encapsulated_proto; 54 }; 55 56 #include <linux/skbuff.h> 57 58 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb) 59 { 60 return (struct vlan_ethhdr *)skb_mac_header(skb); 61 } 62 63 #define VLAN_PRIO_MASK 0xe000 /* Priority Code Point */ 64 #define VLAN_PRIO_SHIFT 13 65 #define VLAN_CFI_MASK 0x1000 /* Canonical Format Indicator / Drop Eligible Indicator */ 66 #define VLAN_VID_MASK 0x0fff /* VLAN Identifier */ 67 #define VLAN_N_VID 4096 68 69 /* found in socket.c */ 70 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *)); 71 72 static inline bool is_vlan_dev(const struct net_device *dev) 73 { 74 return dev->priv_flags & IFF_802_1Q_VLAN; 75 } 76 77 #define skb_vlan_tag_present(__skb) ((__skb)->vlan_present) 78 #define skb_vlan_tag_get(__skb) ((__skb)->vlan_tci) 79 #define skb_vlan_tag_get_id(__skb) ((__skb)->vlan_tci & VLAN_VID_MASK) 80 #define skb_vlan_tag_get_cfi(__skb) (!!((__skb)->vlan_tci & VLAN_CFI_MASK)) 81 #define skb_vlan_tag_get_prio(__skb) (((__skb)->vlan_tci & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT) 82 83 static inline int vlan_get_rx_ctag_filter_info(struct net_device *dev) 84 { 85 ASSERT_RTNL(); 86 return notifier_to_errno(call_netdevice_notifiers(NETDEV_CVLAN_FILTER_PUSH_INFO, dev)); 87 } 88 89 static inline void vlan_drop_rx_ctag_filter_info(struct net_device *dev) 90 { 91 ASSERT_RTNL(); 92 call_netdevice_notifiers(NETDEV_CVLAN_FILTER_DROP_INFO, dev); 93 } 94 95 static inline int vlan_get_rx_stag_filter_info(struct net_device *dev) 96 { 97 ASSERT_RTNL(); 98 return notifier_to_errno(call_netdevice_notifiers(NETDEV_SVLAN_FILTER_PUSH_INFO, dev)); 99 } 100 101 static inline void vlan_drop_rx_stag_filter_info(struct net_device *dev) 102 { 103 ASSERT_RTNL(); 104 call_netdevice_notifiers(NETDEV_SVLAN_FILTER_DROP_INFO, dev); 105 } 106 107 /** 108 * struct vlan_pcpu_stats - VLAN percpu rx/tx stats 109 * @rx_packets: number of received packets 110 * @rx_bytes: number of received bytes 111 * @rx_multicast: number of received multicast packets 112 * @tx_packets: number of transmitted packets 113 * @tx_bytes: number of transmitted bytes 114 * @syncp: synchronization point for 64bit counters 115 * @rx_errors: number of rx errors 116 * @tx_dropped: number of tx drops 117 */ 118 struct vlan_pcpu_stats { 119 u64 rx_packets; 120 u64 rx_bytes; 121 u64 rx_multicast; 122 u64 tx_packets; 123 u64 tx_bytes; 124 struct u64_stats_sync syncp; 125 u32 rx_errors; 126 u32 tx_dropped; 127 }; 128 129 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) 130 131 extern struct net_device *__vlan_find_dev_deep_rcu(struct net_device *real_dev, 132 __be16 vlan_proto, u16 vlan_id); 133 extern int vlan_for_each(struct net_device *dev, 134 int (*action)(struct net_device *dev, int vid, 135 void *arg), void *arg); 136 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev); 137 extern u16 vlan_dev_vlan_id(const struct net_device *dev); 138 extern __be16 vlan_dev_vlan_proto(const struct net_device *dev); 139 140 /** 141 * struct vlan_priority_tci_mapping - vlan egress priority mappings 142 * @priority: skb priority 143 * @vlan_qos: vlan priority: (skb->priority << 13) & 0xE000 144 * @next: pointer to next struct 145 */ 146 struct vlan_priority_tci_mapping { 147 u32 priority; 148 u16 vlan_qos; 149 struct vlan_priority_tci_mapping *next; 150 }; 151 152 struct proc_dir_entry; 153 struct netpoll; 154 155 /** 156 * struct vlan_dev_priv - VLAN private device data 157 * @nr_ingress_mappings: number of ingress priority mappings 158 * @ingress_priority_map: ingress priority mappings 159 * @nr_egress_mappings: number of egress priority mappings 160 * @egress_priority_map: hash of egress priority mappings 161 * @vlan_proto: VLAN encapsulation protocol 162 * @vlan_id: VLAN identifier 163 * @flags: device flags 164 * @real_dev: underlying netdevice 165 * @real_dev_addr: address of underlying netdevice 166 * @dent: proc dir entry 167 * @vlan_pcpu_stats: ptr to percpu rx stats 168 */ 169 struct vlan_dev_priv { 170 unsigned int nr_ingress_mappings; 171 u32 ingress_priority_map[8]; 172 unsigned int nr_egress_mappings; 173 struct vlan_priority_tci_mapping *egress_priority_map[16]; 174 175 __be16 vlan_proto; 176 u16 vlan_id; 177 u16 flags; 178 179 struct net_device *real_dev; 180 unsigned char real_dev_addr[ETH_ALEN]; 181 182 struct proc_dir_entry *dent; 183 struct vlan_pcpu_stats __percpu *vlan_pcpu_stats; 184 #ifdef CONFIG_NET_POLL_CONTROLLER 185 struct netpoll *netpoll; 186 #endif 187 }; 188 189 static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev) 190 { 191 return netdev_priv(dev); 192 } 193 194 static inline u16 195 vlan_dev_get_egress_qos_mask(struct net_device *dev, u32 skprio) 196 { 197 struct vlan_priority_tci_mapping *mp; 198 199 smp_rmb(); /* coupled with smp_wmb() in vlan_dev_set_egress_priority() */ 200 201 mp = vlan_dev_priv(dev)->egress_priority_map[(skprio & 0xF)]; 202 while (mp) { 203 if (mp->priority == skprio) { 204 return mp->vlan_qos; /* This should already be shifted 205 * to mask correctly with the 206 * VLAN's TCI */ 207 } 208 mp = mp->next; 209 } 210 return 0; 211 } 212 213 extern bool vlan_do_receive(struct sk_buff **skb); 214 215 extern int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid); 216 extern void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid); 217 218 extern int vlan_vids_add_by_dev(struct net_device *dev, 219 const struct net_device *by_dev); 220 extern void vlan_vids_del_by_dev(struct net_device *dev, 221 const struct net_device *by_dev); 222 223 extern bool vlan_uses_dev(const struct net_device *dev); 224 225 #else 226 static inline struct net_device * 227 __vlan_find_dev_deep_rcu(struct net_device *real_dev, 228 __be16 vlan_proto, u16 vlan_id) 229 { 230 return NULL; 231 } 232 233 static inline int 234 vlan_for_each(struct net_device *dev, 235 int (*action)(struct net_device *dev, int vid, void *arg), 236 void *arg) 237 { 238 return 0; 239 } 240 241 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev) 242 { 243 BUG(); 244 return NULL; 245 } 246 247 static inline u16 vlan_dev_vlan_id(const struct net_device *dev) 248 { 249 BUG(); 250 return 0; 251 } 252 253 static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev) 254 { 255 BUG(); 256 return 0; 257 } 258 259 static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev, 260 u32 skprio) 261 { 262 return 0; 263 } 264 265 static inline bool vlan_do_receive(struct sk_buff **skb) 266 { 267 return false; 268 } 269 270 static inline int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid) 271 { 272 return 0; 273 } 274 275 static inline void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid) 276 { 277 } 278 279 static inline int vlan_vids_add_by_dev(struct net_device *dev, 280 const struct net_device *by_dev) 281 { 282 return 0; 283 } 284 285 static inline void vlan_vids_del_by_dev(struct net_device *dev, 286 const struct net_device *by_dev) 287 { 288 } 289 290 static inline bool vlan_uses_dev(const struct net_device *dev) 291 { 292 return false; 293 } 294 #endif 295 296 /** 297 * eth_type_vlan - check for valid vlan ether type. 298 * @ethertype: ether type to check 299 * 300 * Returns true if the ether type is a vlan ether type. 301 */ 302 static inline bool eth_type_vlan(__be16 ethertype) 303 { 304 switch (ethertype) { 305 case htons(ETH_P_8021Q): 306 case htons(ETH_P_8021AD): 307 return true; 308 default: 309 return false; 310 } 311 } 312 313 static inline bool vlan_hw_offload_capable(netdev_features_t features, 314 __be16 proto) 315 { 316 if (proto == htons(ETH_P_8021Q) && features & NETIF_F_HW_VLAN_CTAG_TX) 317 return true; 318 if (proto == htons(ETH_P_8021AD) && features & NETIF_F_HW_VLAN_STAG_TX) 319 return true; 320 return false; 321 } 322 323 /** 324 * __vlan_insert_inner_tag - inner VLAN tag inserting 325 * @skb: skbuff to tag 326 * @vlan_proto: VLAN encapsulation protocol 327 * @vlan_tci: VLAN TCI to insert 328 * @mac_len: MAC header length including outer vlan headers 329 * 330 * Inserts the VLAN tag into @skb as part of the payload at offset mac_len 331 * Returns error if skb_cow_head fails. 332 * 333 * Does not change skb->protocol so this function can be used during receive. 334 */ 335 static inline int __vlan_insert_inner_tag(struct sk_buff *skb, 336 __be16 vlan_proto, u16 vlan_tci, 337 unsigned int mac_len) 338 { 339 struct vlan_ethhdr *veth; 340 341 if (skb_cow_head(skb, VLAN_HLEN) < 0) 342 return -ENOMEM; 343 344 skb_push(skb, VLAN_HLEN); 345 346 /* Move the mac header sans proto to the beginning of the new header. */ 347 if (likely(mac_len > ETH_TLEN)) 348 memmove(skb->data, skb->data + VLAN_HLEN, mac_len - ETH_TLEN); 349 skb->mac_header -= VLAN_HLEN; 350 351 veth = (struct vlan_ethhdr *)(skb->data + mac_len - ETH_HLEN); 352 353 /* first, the ethernet type */ 354 if (likely(mac_len >= ETH_TLEN)) { 355 /* h_vlan_encapsulated_proto should already be populated, and 356 * skb->data has space for h_vlan_proto 357 */ 358 veth->h_vlan_proto = vlan_proto; 359 } else { 360 /* h_vlan_encapsulated_proto should not be populated, and 361 * skb->data has no space for h_vlan_proto 362 */ 363 veth->h_vlan_encapsulated_proto = skb->protocol; 364 } 365 366 /* now, the TCI */ 367 veth->h_vlan_TCI = htons(vlan_tci); 368 369 return 0; 370 } 371 372 /** 373 * __vlan_insert_tag - regular VLAN tag inserting 374 * @skb: skbuff to tag 375 * @vlan_proto: VLAN encapsulation protocol 376 * @vlan_tci: VLAN TCI to insert 377 * 378 * Inserts the VLAN tag into @skb as part of the payload 379 * Returns error if skb_cow_head fails. 380 * 381 * Does not change skb->protocol so this function can be used during receive. 382 */ 383 static inline int __vlan_insert_tag(struct sk_buff *skb, 384 __be16 vlan_proto, u16 vlan_tci) 385 { 386 return __vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, ETH_HLEN); 387 } 388 389 /** 390 * vlan_insert_inner_tag - inner VLAN tag inserting 391 * @skb: skbuff to tag 392 * @vlan_proto: VLAN encapsulation protocol 393 * @vlan_tci: VLAN TCI to insert 394 * @mac_len: MAC header length including outer vlan headers 395 * 396 * Inserts the VLAN tag into @skb as part of the payload at offset mac_len 397 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed. 398 * 399 * Following the skb_unshare() example, in case of error, the calling function 400 * doesn't have to worry about freeing the original skb. 401 * 402 * Does not change skb->protocol so this function can be used during receive. 403 */ 404 static inline struct sk_buff *vlan_insert_inner_tag(struct sk_buff *skb, 405 __be16 vlan_proto, 406 u16 vlan_tci, 407 unsigned int mac_len) 408 { 409 int err; 410 411 err = __vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, mac_len); 412 if (err) { 413 dev_kfree_skb_any(skb); 414 return NULL; 415 } 416 return skb; 417 } 418 419 /** 420 * vlan_insert_tag - regular VLAN tag inserting 421 * @skb: skbuff to tag 422 * @vlan_proto: VLAN encapsulation protocol 423 * @vlan_tci: VLAN TCI to insert 424 * 425 * Inserts the VLAN tag into @skb as part of the payload 426 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed. 427 * 428 * Following the skb_unshare() example, in case of error, the calling function 429 * doesn't have to worry about freeing the original skb. 430 * 431 * Does not change skb->protocol so this function can be used during receive. 432 */ 433 static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb, 434 __be16 vlan_proto, u16 vlan_tci) 435 { 436 return vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, ETH_HLEN); 437 } 438 439 /** 440 * vlan_insert_tag_set_proto - regular VLAN tag inserting 441 * @skb: skbuff to tag 442 * @vlan_proto: VLAN encapsulation protocol 443 * @vlan_tci: VLAN TCI to insert 444 * 445 * Inserts the VLAN tag into @skb as part of the payload 446 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed. 447 * 448 * Following the skb_unshare() example, in case of error, the calling function 449 * doesn't have to worry about freeing the original skb. 450 */ 451 static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb, 452 __be16 vlan_proto, 453 u16 vlan_tci) 454 { 455 skb = vlan_insert_tag(skb, vlan_proto, vlan_tci); 456 if (skb) 457 skb->protocol = vlan_proto; 458 return skb; 459 } 460 461 /** 462 * __vlan_hwaccel_clear_tag - clear hardware accelerated VLAN info 463 * @skb: skbuff to clear 464 * 465 * Clears the VLAN information from @skb 466 */ 467 static inline void __vlan_hwaccel_clear_tag(struct sk_buff *skb) 468 { 469 skb->vlan_present = 0; 470 } 471 472 /** 473 * __vlan_hwaccel_copy_tag - copy hardware accelerated VLAN info from another skb 474 * @dst: skbuff to copy to 475 * @src: skbuff to copy from 476 * 477 * Copies VLAN information from @src to @dst (for branchless code) 478 */ 479 static inline void __vlan_hwaccel_copy_tag(struct sk_buff *dst, const struct sk_buff *src) 480 { 481 dst->vlan_present = src->vlan_present; 482 dst->vlan_proto = src->vlan_proto; 483 dst->vlan_tci = src->vlan_tci; 484 } 485 486 /* 487 * __vlan_hwaccel_push_inside - pushes vlan tag to the payload 488 * @skb: skbuff to tag 489 * 490 * Pushes the VLAN tag from @skb->vlan_tci inside to the payload. 491 * 492 * Following the skb_unshare() example, in case of error, the calling function 493 * doesn't have to worry about freeing the original skb. 494 */ 495 static inline struct sk_buff *__vlan_hwaccel_push_inside(struct sk_buff *skb) 496 { 497 skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto, 498 skb_vlan_tag_get(skb)); 499 if (likely(skb)) 500 __vlan_hwaccel_clear_tag(skb); 501 return skb; 502 } 503 504 /** 505 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting 506 * @skb: skbuff to tag 507 * @vlan_proto: VLAN encapsulation protocol 508 * @vlan_tci: VLAN TCI to insert 509 * 510 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest 511 */ 512 static inline void __vlan_hwaccel_put_tag(struct sk_buff *skb, 513 __be16 vlan_proto, u16 vlan_tci) 514 { 515 skb->vlan_proto = vlan_proto; 516 skb->vlan_tci = vlan_tci; 517 skb->vlan_present = 1; 518 } 519 520 /** 521 * __vlan_get_tag - get the VLAN ID that is part of the payload 522 * @skb: skbuff to query 523 * @vlan_tci: buffer to store value 524 * 525 * Returns error if the skb is not of VLAN type 526 */ 527 static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) 528 { 529 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data; 530 531 if (!eth_type_vlan(veth->h_vlan_proto)) 532 return -EINVAL; 533 534 *vlan_tci = ntohs(veth->h_vlan_TCI); 535 return 0; 536 } 537 538 /** 539 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[] 540 * @skb: skbuff to query 541 * @vlan_tci: buffer to store value 542 * 543 * Returns error if @skb->vlan_tci is not set correctly 544 */ 545 static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb, 546 u16 *vlan_tci) 547 { 548 if (skb_vlan_tag_present(skb)) { 549 *vlan_tci = skb_vlan_tag_get(skb); 550 return 0; 551 } else { 552 *vlan_tci = 0; 553 return -EINVAL; 554 } 555 } 556 557 /** 558 * vlan_get_tag - get the VLAN ID from the skb 559 * @skb: skbuff to query 560 * @vlan_tci: buffer to store value 561 * 562 * Returns error if the skb is not VLAN tagged 563 */ 564 static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) 565 { 566 if (skb->dev->features & NETIF_F_HW_VLAN_CTAG_TX) { 567 return __vlan_hwaccel_get_tag(skb, vlan_tci); 568 } else { 569 return __vlan_get_tag(skb, vlan_tci); 570 } 571 } 572 573 /** 574 * vlan_get_protocol - get protocol EtherType. 575 * @skb: skbuff to query 576 * @type: first vlan protocol 577 * @depth: buffer to store length of eth and vlan tags in bytes 578 * 579 * Returns the EtherType of the packet, regardless of whether it is 580 * vlan encapsulated (normal or hardware accelerated) or not. 581 */ 582 static inline __be16 __vlan_get_protocol(const struct sk_buff *skb, __be16 type, 583 int *depth) 584 { 585 unsigned int vlan_depth = skb->mac_len, parse_depth = VLAN_MAX_DEPTH; 586 587 /* if type is 802.1Q/AD then the header should already be 588 * present at mac_len - VLAN_HLEN (if mac_len > 0), or at 589 * ETH_HLEN otherwise 590 */ 591 if (eth_type_vlan(type)) { 592 if (vlan_depth) { 593 if (WARN_ON(vlan_depth < VLAN_HLEN)) 594 return 0; 595 vlan_depth -= VLAN_HLEN; 596 } else { 597 vlan_depth = ETH_HLEN; 598 } 599 do { 600 struct vlan_hdr vhdr, *vh; 601 602 vh = skb_header_pointer(skb, vlan_depth, sizeof(vhdr), &vhdr); 603 if (unlikely(!vh || !--parse_depth)) 604 return 0; 605 606 type = vh->h_vlan_encapsulated_proto; 607 vlan_depth += VLAN_HLEN; 608 } while (eth_type_vlan(type)); 609 } 610 611 if (depth) 612 *depth = vlan_depth; 613 614 return type; 615 } 616 617 /** 618 * vlan_get_protocol - get protocol EtherType. 619 * @skb: skbuff to query 620 * 621 * Returns the EtherType of the packet, regardless of whether it is 622 * vlan encapsulated (normal or hardware accelerated) or not. 623 */ 624 static inline __be16 vlan_get_protocol(const struct sk_buff *skb) 625 { 626 return __vlan_get_protocol(skb, skb->protocol, NULL); 627 } 628 629 /* A getter for the SKB protocol field which will handle VLAN tags consistently 630 * whether VLAN acceleration is enabled or not. 631 */ 632 static inline __be16 skb_protocol(const struct sk_buff *skb, bool skip_vlan) 633 { 634 if (!skip_vlan) 635 /* VLAN acceleration strips the VLAN header from the skb and 636 * moves it to skb->vlan_proto 637 */ 638 return skb_vlan_tag_present(skb) ? skb->vlan_proto : skb->protocol; 639 640 return vlan_get_protocol(skb); 641 } 642 643 static inline void vlan_set_encap_proto(struct sk_buff *skb, 644 struct vlan_hdr *vhdr) 645 { 646 __be16 proto; 647 unsigned short *rawp; 648 649 /* 650 * Was a VLAN packet, grab the encapsulated protocol, which the layer 651 * three protocols care about. 652 */ 653 654 proto = vhdr->h_vlan_encapsulated_proto; 655 if (eth_proto_is_802_3(proto)) { 656 skb->protocol = proto; 657 return; 658 } 659 660 rawp = (unsigned short *)(vhdr + 1); 661 if (*rawp == 0xFFFF) 662 /* 663 * This is a magic hack to spot IPX packets. Older Novell 664 * breaks the protocol design and runs IPX over 802.3 without 665 * an 802.2 LLC layer. We look for FFFF which isn't a used 666 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware 667 * but does for the rest. 668 */ 669 skb->protocol = htons(ETH_P_802_3); 670 else 671 /* 672 * Real 802.2 LLC 673 */ 674 skb->protocol = htons(ETH_P_802_2); 675 } 676 677 /** 678 * skb_vlan_tagged - check if skb is vlan tagged. 679 * @skb: skbuff to query 680 * 681 * Returns true if the skb is tagged, regardless of whether it is hardware 682 * accelerated or not. 683 */ 684 static inline bool skb_vlan_tagged(const struct sk_buff *skb) 685 { 686 if (!skb_vlan_tag_present(skb) && 687 likely(!eth_type_vlan(skb->protocol))) 688 return false; 689 690 return true; 691 } 692 693 /** 694 * skb_vlan_tagged_multi - check if skb is vlan tagged with multiple headers. 695 * @skb: skbuff to query 696 * 697 * Returns true if the skb is tagged with multiple vlan headers, regardless 698 * of whether it is hardware accelerated or not. 699 */ 700 static inline bool skb_vlan_tagged_multi(struct sk_buff *skb) 701 { 702 __be16 protocol = skb->protocol; 703 704 if (!skb_vlan_tag_present(skb)) { 705 struct vlan_ethhdr *veh; 706 707 if (likely(!eth_type_vlan(protocol))) 708 return false; 709 710 if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN))) 711 return false; 712 713 veh = (struct vlan_ethhdr *)skb->data; 714 protocol = veh->h_vlan_encapsulated_proto; 715 } 716 717 if (!eth_type_vlan(protocol)) 718 return false; 719 720 return true; 721 } 722 723 /** 724 * vlan_features_check - drop unsafe features for skb with multiple tags. 725 * @skb: skbuff to query 726 * @features: features to be checked 727 * 728 * Returns features without unsafe ones if the skb has multiple tags. 729 */ 730 static inline netdev_features_t vlan_features_check(struct sk_buff *skb, 731 netdev_features_t features) 732 { 733 if (skb_vlan_tagged_multi(skb)) { 734 /* In the case of multi-tagged packets, use a direct mask 735 * instead of using netdev_interesect_features(), to make 736 * sure that only devices supporting NETIF_F_HW_CSUM will 737 * have checksum offloading support. 738 */ 739 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_HW_CSUM | 740 NETIF_F_FRAGLIST | NETIF_F_HW_VLAN_CTAG_TX | 741 NETIF_F_HW_VLAN_STAG_TX; 742 } 743 744 return features; 745 } 746 747 /** 748 * compare_vlan_header - Compare two vlan headers 749 * @h1: Pointer to vlan header 750 * @h2: Pointer to vlan header 751 * 752 * Compare two vlan headers, returns 0 if equal. 753 * 754 * Please note that alignment of h1 & h2 are only guaranteed to be 16 bits. 755 */ 756 static inline unsigned long compare_vlan_header(const struct vlan_hdr *h1, 757 const struct vlan_hdr *h2) 758 { 759 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 760 return *(u32 *)h1 ^ *(u32 *)h2; 761 #else 762 return ((__force u32)h1->h_vlan_TCI ^ (__force u32)h2->h_vlan_TCI) | 763 ((__force u32)h1->h_vlan_encapsulated_proto ^ 764 (__force u32)h2->h_vlan_encapsulated_proto); 765 #endif 766 } 767 #endif /* !(_LINUX_IF_VLAN_H_) */ 768