1 /* 2 * VLAN An implementation of 802.1Q VLAN tagging. 3 * 4 * Authors: Ben Greear <greearb@candelatech.com> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 * 11 */ 12 #ifndef _LINUX_IF_VLAN_H_ 13 #define _LINUX_IF_VLAN_H_ 14 15 #include <linux/netdevice.h> 16 #include <linux/etherdevice.h> 17 #include <linux/rtnetlink.h> 18 #include <linux/bug.h> 19 #include <uapi/linux/if_vlan.h> 20 21 #define VLAN_HLEN 4 /* The additional bytes required by VLAN 22 * (in addition to the Ethernet header) 23 */ 24 #define VLAN_ETH_HLEN 18 /* Total octets in header. */ 25 #define VLAN_ETH_ZLEN 64 /* Min. octets in frame sans FCS */ 26 27 /* 28 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan 29 */ 30 #define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */ 31 #define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */ 32 33 /* 34 * struct vlan_hdr - vlan header 35 * @h_vlan_TCI: priority and VLAN ID 36 * @h_vlan_encapsulated_proto: packet type ID or len 37 */ 38 struct vlan_hdr { 39 __be16 h_vlan_TCI; 40 __be16 h_vlan_encapsulated_proto; 41 }; 42 43 /** 44 * struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr) 45 * @h_dest: destination ethernet address 46 * @h_source: source ethernet address 47 * @h_vlan_proto: ethernet protocol 48 * @h_vlan_TCI: priority and VLAN ID 49 * @h_vlan_encapsulated_proto: packet type ID or len 50 */ 51 struct vlan_ethhdr { 52 unsigned char h_dest[ETH_ALEN]; 53 unsigned char h_source[ETH_ALEN]; 54 __be16 h_vlan_proto; 55 __be16 h_vlan_TCI; 56 __be16 h_vlan_encapsulated_proto; 57 }; 58 59 #include <linux/skbuff.h> 60 61 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb) 62 { 63 return (struct vlan_ethhdr *)skb_mac_header(skb); 64 } 65 66 #define VLAN_PRIO_MASK 0xe000 /* Priority Code Point */ 67 #define VLAN_PRIO_SHIFT 13 68 #define VLAN_CFI_MASK 0x1000 /* Canonical Format Indicator */ 69 #define VLAN_TAG_PRESENT VLAN_CFI_MASK 70 #define VLAN_VID_MASK 0x0fff /* VLAN Identifier */ 71 #define VLAN_N_VID 4096 72 73 /* found in socket.c */ 74 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *)); 75 76 static inline int is_vlan_dev(struct net_device *dev) 77 { 78 return dev->priv_flags & IFF_802_1Q_VLAN; 79 } 80 81 #define vlan_tx_tag_present(__skb) ((__skb)->vlan_tci & VLAN_TAG_PRESENT) 82 #define vlan_tx_tag_get(__skb) ((__skb)->vlan_tci & ~VLAN_TAG_PRESENT) 83 #define vlan_tx_tag_get_id(__skb) ((__skb)->vlan_tci & VLAN_VID_MASK) 84 85 /** 86 * struct vlan_pcpu_stats - VLAN percpu rx/tx stats 87 * @rx_packets: number of received packets 88 * @rx_bytes: number of received bytes 89 * @rx_multicast: number of received multicast packets 90 * @tx_packets: number of transmitted packets 91 * @tx_bytes: number of transmitted bytes 92 * @syncp: synchronization point for 64bit counters 93 * @rx_errors: number of rx errors 94 * @tx_dropped: number of tx drops 95 */ 96 struct vlan_pcpu_stats { 97 u64 rx_packets; 98 u64 rx_bytes; 99 u64 rx_multicast; 100 u64 tx_packets; 101 u64 tx_bytes; 102 struct u64_stats_sync syncp; 103 u32 rx_errors; 104 u32 tx_dropped; 105 }; 106 107 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) 108 109 extern struct net_device *__vlan_find_dev_deep(struct net_device *real_dev, 110 __be16 vlan_proto, u16 vlan_id); 111 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev); 112 extern u16 vlan_dev_vlan_id(const struct net_device *dev); 113 extern __be16 vlan_dev_vlan_proto(const struct net_device *dev); 114 115 /** 116 * struct vlan_priority_tci_mapping - vlan egress priority mappings 117 * @priority: skb priority 118 * @vlan_qos: vlan priority: (skb->priority << 13) & 0xE000 119 * @next: pointer to next struct 120 */ 121 struct vlan_priority_tci_mapping { 122 u32 priority; 123 u16 vlan_qos; 124 struct vlan_priority_tci_mapping *next; 125 }; 126 127 struct proc_dir_entry; 128 struct netpoll; 129 130 /** 131 * struct vlan_dev_priv - VLAN private device data 132 * @nr_ingress_mappings: number of ingress priority mappings 133 * @ingress_priority_map: ingress priority mappings 134 * @nr_egress_mappings: number of egress priority mappings 135 * @egress_priority_map: hash of egress priority mappings 136 * @vlan_proto: VLAN encapsulation protocol 137 * @vlan_id: VLAN identifier 138 * @flags: device flags 139 * @real_dev: underlying netdevice 140 * @real_dev_addr: address of underlying netdevice 141 * @dent: proc dir entry 142 * @vlan_pcpu_stats: ptr to percpu rx stats 143 */ 144 struct vlan_dev_priv { 145 unsigned int nr_ingress_mappings; 146 u32 ingress_priority_map[8]; 147 unsigned int nr_egress_mappings; 148 struct vlan_priority_tci_mapping *egress_priority_map[16]; 149 150 __be16 vlan_proto; 151 u16 vlan_id; 152 u16 flags; 153 154 struct net_device *real_dev; 155 unsigned char real_dev_addr[ETH_ALEN]; 156 157 struct proc_dir_entry *dent; 158 struct vlan_pcpu_stats __percpu *vlan_pcpu_stats; 159 #ifdef CONFIG_NET_POLL_CONTROLLER 160 struct netpoll *netpoll; 161 #endif 162 }; 163 164 static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev) 165 { 166 return netdev_priv(dev); 167 } 168 169 static inline u16 170 vlan_dev_get_egress_qos_mask(struct net_device *dev, u32 skprio) 171 { 172 struct vlan_priority_tci_mapping *mp; 173 174 smp_rmb(); /* coupled with smp_wmb() in vlan_dev_set_egress_priority() */ 175 176 mp = vlan_dev_priv(dev)->egress_priority_map[(skprio & 0xF)]; 177 while (mp) { 178 if (mp->priority == skprio) { 179 return mp->vlan_qos; /* This should already be shifted 180 * to mask correctly with the 181 * VLAN's TCI */ 182 } 183 mp = mp->next; 184 } 185 return 0; 186 } 187 188 extern bool vlan_do_receive(struct sk_buff **skb); 189 extern struct sk_buff *vlan_untag(struct sk_buff *skb); 190 191 extern int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid); 192 extern void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid); 193 194 extern int vlan_vids_add_by_dev(struct net_device *dev, 195 const struct net_device *by_dev); 196 extern void vlan_vids_del_by_dev(struct net_device *dev, 197 const struct net_device *by_dev); 198 199 extern bool vlan_uses_dev(const struct net_device *dev); 200 #else 201 static inline struct net_device * 202 __vlan_find_dev_deep(struct net_device *real_dev, 203 __be16 vlan_proto, u16 vlan_id) 204 { 205 return NULL; 206 } 207 208 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev) 209 { 210 BUG(); 211 return NULL; 212 } 213 214 static inline u16 vlan_dev_vlan_id(const struct net_device *dev) 215 { 216 BUG(); 217 return 0; 218 } 219 220 static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev) 221 { 222 BUG(); 223 return 0; 224 } 225 226 static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev, 227 u32 skprio) 228 { 229 return 0; 230 } 231 232 static inline bool vlan_do_receive(struct sk_buff **skb) 233 { 234 return false; 235 } 236 237 static inline struct sk_buff *vlan_untag(struct sk_buff *skb) 238 { 239 return skb; 240 } 241 242 static inline int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid) 243 { 244 return 0; 245 } 246 247 static inline void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid) 248 { 249 } 250 251 static inline int vlan_vids_add_by_dev(struct net_device *dev, 252 const struct net_device *by_dev) 253 { 254 return 0; 255 } 256 257 static inline void vlan_vids_del_by_dev(struct net_device *dev, 258 const struct net_device *by_dev) 259 { 260 } 261 262 static inline bool vlan_uses_dev(const struct net_device *dev) 263 { 264 return false; 265 } 266 #endif 267 268 static inline bool vlan_hw_offload_capable(netdev_features_t features, 269 __be16 proto) 270 { 271 if (proto == htons(ETH_P_8021Q) && features & NETIF_F_HW_VLAN_CTAG_TX) 272 return true; 273 if (proto == htons(ETH_P_8021AD) && features & NETIF_F_HW_VLAN_STAG_TX) 274 return true; 275 return false; 276 } 277 278 /** 279 * vlan_insert_tag - regular VLAN tag inserting 280 * @skb: skbuff to tag 281 * @vlan_proto: VLAN encapsulation protocol 282 * @vlan_tci: VLAN TCI to insert 283 * 284 * Inserts the VLAN tag into @skb as part of the payload 285 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed. 286 * 287 * Following the skb_unshare() example, in case of error, the calling function 288 * doesn't have to worry about freeing the original skb. 289 * 290 * Does not change skb->protocol so this function can be used during receive. 291 */ 292 static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb, 293 __be16 vlan_proto, u16 vlan_tci) 294 { 295 struct vlan_ethhdr *veth; 296 297 if (skb_cow_head(skb, VLAN_HLEN) < 0) { 298 dev_kfree_skb_any(skb); 299 return NULL; 300 } 301 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN); 302 303 /* Move the mac addresses to the beginning of the new header. */ 304 memmove(skb->data, skb->data + VLAN_HLEN, 2 * ETH_ALEN); 305 skb->mac_header -= VLAN_HLEN; 306 307 /* first, the ethernet type */ 308 veth->h_vlan_proto = vlan_proto; 309 310 /* now, the TCI */ 311 veth->h_vlan_TCI = htons(vlan_tci); 312 313 return skb; 314 } 315 316 /** 317 * __vlan_put_tag - regular VLAN tag inserting 318 * @skb: skbuff to tag 319 * @vlan_tci: VLAN TCI to insert 320 * 321 * Inserts the VLAN tag into @skb as part of the payload 322 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed. 323 * 324 * Following the skb_unshare() example, in case of error, the calling function 325 * doesn't have to worry about freeing the original skb. 326 */ 327 static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, 328 __be16 vlan_proto, u16 vlan_tci) 329 { 330 skb = vlan_insert_tag(skb, vlan_proto, vlan_tci); 331 if (skb) 332 skb->protocol = vlan_proto; 333 return skb; 334 } 335 336 /** 337 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting 338 * @skb: skbuff to tag 339 * @vlan_proto: VLAN encapsulation protocol 340 * @vlan_tci: VLAN TCI to insert 341 * 342 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest 343 */ 344 static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, 345 __be16 vlan_proto, 346 u16 vlan_tci) 347 { 348 skb->vlan_proto = vlan_proto; 349 skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci; 350 return skb; 351 } 352 353 /** 354 * vlan_put_tag - inserts VLAN tag according to device features 355 * @skb: skbuff to tag 356 * @vlan_tci: VLAN TCI to insert 357 * 358 * Assumes skb->dev is the target that will xmit this frame. 359 * Returns a VLAN tagged skb. 360 */ 361 static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, 362 __be16 vlan_proto, u16 vlan_tci) 363 { 364 if (vlan_hw_offload_capable(skb->dev->features, vlan_proto)) { 365 return __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci); 366 } else { 367 return __vlan_put_tag(skb, vlan_proto, vlan_tci); 368 } 369 } 370 371 /** 372 * __vlan_get_tag - get the VLAN ID that is part of the payload 373 * @skb: skbuff to query 374 * @vlan_tci: buffer to store vlaue 375 * 376 * Returns error if the skb is not of VLAN type 377 */ 378 static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) 379 { 380 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data; 381 382 if (veth->h_vlan_proto != htons(ETH_P_8021Q) && 383 veth->h_vlan_proto != htons(ETH_P_8021AD)) 384 return -EINVAL; 385 386 *vlan_tci = ntohs(veth->h_vlan_TCI); 387 return 0; 388 } 389 390 /** 391 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[] 392 * @skb: skbuff to query 393 * @vlan_tci: buffer to store vlaue 394 * 395 * Returns error if @skb->vlan_tci is not set correctly 396 */ 397 static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb, 398 u16 *vlan_tci) 399 { 400 if (vlan_tx_tag_present(skb)) { 401 *vlan_tci = vlan_tx_tag_get(skb); 402 return 0; 403 } else { 404 *vlan_tci = 0; 405 return -EINVAL; 406 } 407 } 408 409 #define HAVE_VLAN_GET_TAG 410 411 /** 412 * vlan_get_tag - get the VLAN ID from the skb 413 * @skb: skbuff to query 414 * @vlan_tci: buffer to store vlaue 415 * 416 * Returns error if the skb is not VLAN tagged 417 */ 418 static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) 419 { 420 if (skb->dev->features & NETIF_F_HW_VLAN_CTAG_TX) { 421 return __vlan_hwaccel_get_tag(skb, vlan_tci); 422 } else { 423 return __vlan_get_tag(skb, vlan_tci); 424 } 425 } 426 427 /** 428 * vlan_get_protocol - get protocol EtherType. 429 * @skb: skbuff to query 430 * 431 * Returns the EtherType of the packet, regardless of whether it is 432 * vlan encapsulated (normal or hardware accelerated) or not. 433 */ 434 static inline __be16 vlan_get_protocol(const struct sk_buff *skb) 435 { 436 __be16 protocol = 0; 437 438 if (vlan_tx_tag_present(skb) || 439 skb->protocol != cpu_to_be16(ETH_P_8021Q)) 440 protocol = skb->protocol; 441 else { 442 __be16 proto, *protop; 443 protop = skb_header_pointer(skb, offsetof(struct vlan_ethhdr, 444 h_vlan_encapsulated_proto), 445 sizeof(proto), &proto); 446 if (likely(protop)) 447 protocol = *protop; 448 } 449 450 return protocol; 451 } 452 453 static inline void vlan_set_encap_proto(struct sk_buff *skb, 454 struct vlan_hdr *vhdr) 455 { 456 __be16 proto; 457 unsigned short *rawp; 458 459 /* 460 * Was a VLAN packet, grab the encapsulated protocol, which the layer 461 * three protocols care about. 462 */ 463 464 proto = vhdr->h_vlan_encapsulated_proto; 465 if (ntohs(proto) >= ETH_P_802_3_MIN) { 466 skb->protocol = proto; 467 return; 468 } 469 470 rawp = (unsigned short *)(vhdr + 1); 471 if (*rawp == 0xFFFF) 472 /* 473 * This is a magic hack to spot IPX packets. Older Novell 474 * breaks the protocol design and runs IPX over 802.3 without 475 * an 802.2 LLC layer. We look for FFFF which isn't a used 476 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware 477 * but does for the rest. 478 */ 479 skb->protocol = htons(ETH_P_802_3); 480 else 481 /* 482 * Real 802.2 LLC 483 */ 484 skb->protocol = htons(ETH_P_802_2); 485 } 486 #endif /* !(_LINUX_IF_VLAN_H_) */ 487