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 13 #ifndef _LINUX_IF_VLAN_H_ 14 #define _LINUX_IF_VLAN_H_ 15 16 #ifdef __KERNEL__ 17 #include <linux/netdevice.h> 18 #include <linux/etherdevice.h> 19 #include <linux/rtnetlink.h> 20 21 #define VLAN_HLEN 4 /* The additional bytes (on top of the Ethernet header) 22 * that VLAN requires. 23 */ 24 #define VLAN_ETH_ALEN 6 /* Octets in one ethernet addr */ 25 #define VLAN_ETH_HLEN 18 /* Total octets in header. */ 26 #define VLAN_ETH_ZLEN 64 /* Min. octets in frame sans FCS */ 27 28 /* 29 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan 30 */ 31 #define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */ 32 #define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */ 33 34 /* 35 * struct vlan_hdr - vlan header 36 * @h_vlan_TCI: priority and VLAN ID 37 * @h_vlan_encapsulated_proto: packet type ID or len 38 */ 39 struct vlan_hdr { 40 __be16 h_vlan_TCI; 41 __be16 h_vlan_encapsulated_proto; 42 }; 43 44 /** 45 * struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr) 46 * @h_dest: destination ethernet address 47 * @h_source: source ethernet address 48 * @h_vlan_proto: ethernet protocol (always 0x8100) 49 * @h_vlan_TCI: priority and VLAN ID 50 * @h_vlan_encapsulated_proto: packet type ID or len 51 */ 52 struct vlan_ethhdr { 53 unsigned char h_dest[ETH_ALEN]; 54 unsigned char h_source[ETH_ALEN]; 55 __be16 h_vlan_proto; 56 __be16 h_vlan_TCI; 57 __be16 h_vlan_encapsulated_proto; 58 }; 59 60 #include <linux/skbuff.h> 61 62 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb) 63 { 64 return (struct vlan_ethhdr *)skb_mac_header(skb); 65 } 66 67 #define VLAN_PRIO_MASK 0xe000 /* Priority Code Point */ 68 #define VLAN_PRIO_SHIFT 13 69 #define VLAN_CFI_MASK 0x1000 /* Canonical Format Indicator */ 70 #define VLAN_TAG_PRESENT VLAN_CFI_MASK 71 #define VLAN_VID_MASK 0x0fff /* VLAN Identifier */ 72 #define VLAN_N_VID 4096 73 74 /* found in socket.c */ 75 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *)); 76 77 /* if this changes, algorithm will have to be reworked because this 78 * depends on completely exhausting the VLAN identifier space. Thus 79 * it gives constant time look-up, but in many cases it wastes memory. 80 */ 81 #define VLAN_GROUP_ARRAY_SPLIT_PARTS 8 82 #define VLAN_GROUP_ARRAY_PART_LEN (VLAN_N_VID/VLAN_GROUP_ARRAY_SPLIT_PARTS) 83 84 struct vlan_group { 85 struct net_device *real_dev; /* The ethernet(like) device 86 * the vlan is attached to. 87 */ 88 unsigned int nr_vlans; 89 struct hlist_node hlist; /* linked list */ 90 struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS]; 91 struct rcu_head rcu; 92 }; 93 94 static inline struct net_device *vlan_group_get_device(struct vlan_group *vg, 95 u16 vlan_id) 96 { 97 struct net_device **array; 98 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN]; 99 return array ? array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] : NULL; 100 } 101 102 static inline void vlan_group_set_device(struct vlan_group *vg, 103 u16 vlan_id, 104 struct net_device *dev) 105 { 106 struct net_device **array; 107 if (!vg) 108 return; 109 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN]; 110 array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] = dev; 111 } 112 113 static inline int is_vlan_dev(struct net_device *dev) 114 { 115 return dev->priv_flags & IFF_802_1Q_VLAN; 116 } 117 118 #define vlan_tx_tag_present(__skb) ((__skb)->vlan_tci & VLAN_TAG_PRESENT) 119 #define vlan_tx_tag_get(__skb) ((__skb)->vlan_tci & ~VLAN_TAG_PRESENT) 120 121 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) 122 /* Must be invoked with rcu_read_lock or with RTNL. */ 123 static inline struct net_device *vlan_find_dev(struct net_device *real_dev, 124 u16 vlan_id) 125 { 126 struct vlan_group *grp = rcu_dereference_rtnl(real_dev->vlgrp); 127 128 if (grp) 129 return vlan_group_get_device(grp, vlan_id); 130 131 return NULL; 132 } 133 134 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev); 135 extern u16 vlan_dev_vlan_id(const struct net_device *dev); 136 137 extern int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp, 138 u16 vlan_tci, int polling); 139 extern bool vlan_do_receive(struct sk_buff **skb); 140 extern struct sk_buff *vlan_untag(struct sk_buff *skb); 141 extern gro_result_t 142 vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp, 143 unsigned int vlan_tci, struct sk_buff *skb); 144 extern gro_result_t 145 vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp, 146 unsigned int vlan_tci); 147 148 #else 149 static inline struct net_device *vlan_find_dev(struct net_device *real_dev, 150 u16 vlan_id) 151 { 152 return NULL; 153 } 154 155 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev) 156 { 157 BUG(); 158 return NULL; 159 } 160 161 static inline u16 vlan_dev_vlan_id(const struct net_device *dev) 162 { 163 BUG(); 164 return 0; 165 } 166 167 static inline int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp, 168 u16 vlan_tci, int polling) 169 { 170 BUG(); 171 return NET_XMIT_SUCCESS; 172 } 173 174 static inline bool vlan_do_receive(struct sk_buff **skb) 175 { 176 if ((*skb)->vlan_tci & VLAN_VID_MASK) 177 (*skb)->pkt_type = PACKET_OTHERHOST; 178 return false; 179 } 180 181 static inline struct sk_buff *vlan_untag(struct sk_buff *skb) 182 { 183 return skb; 184 } 185 186 static inline gro_result_t 187 vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp, 188 unsigned int vlan_tci, struct sk_buff *skb) 189 { 190 return GRO_DROP; 191 } 192 193 static inline gro_result_t 194 vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp, 195 unsigned int vlan_tci) 196 { 197 return GRO_DROP; 198 } 199 #endif 200 201 /** 202 * vlan_hwaccel_rx - netif_rx wrapper for VLAN RX acceleration 203 * @skb: buffer 204 * @grp: vlan group 205 * @vlan_tci: VLAN TCI as received from the card 206 */ 207 static inline int vlan_hwaccel_rx(struct sk_buff *skb, 208 struct vlan_group *grp, 209 u16 vlan_tci) 210 { 211 return __vlan_hwaccel_rx(skb, grp, vlan_tci, 0); 212 } 213 214 /** 215 * vlan_hwaccel_receive_skb - netif_receive_skb wrapper for VLAN RX acceleration 216 * @skb: buffer 217 * @grp: vlan group 218 * @vlan_tci: VLAN TCI as received from the card 219 */ 220 static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb, 221 struct vlan_group *grp, 222 u16 vlan_tci) 223 { 224 return __vlan_hwaccel_rx(skb, grp, vlan_tci, 1); 225 } 226 227 /** 228 * __vlan_put_tag - regular VLAN tag inserting 229 * @skb: skbuff to tag 230 * @vlan_tci: VLAN TCI to insert 231 * 232 * Inserts the VLAN tag into @skb as part of the payload 233 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed. 234 * 235 * Following the skb_unshare() example, in case of error, the calling function 236 * doesn't have to worry about freeing the original skb. 237 */ 238 static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, u16 vlan_tci) 239 { 240 struct vlan_ethhdr *veth; 241 242 if (skb_cow_head(skb, VLAN_HLEN) < 0) { 243 kfree_skb(skb); 244 return NULL; 245 } 246 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN); 247 248 /* Move the mac addresses to the beginning of the new header. */ 249 memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN); 250 skb->mac_header -= VLAN_HLEN; 251 252 /* first, the ethernet type */ 253 veth->h_vlan_proto = htons(ETH_P_8021Q); 254 255 /* now, the TCI */ 256 veth->h_vlan_TCI = htons(vlan_tci); 257 258 skb->protocol = htons(ETH_P_8021Q); 259 260 return skb; 261 } 262 263 /** 264 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting 265 * @skb: skbuff to tag 266 * @vlan_tci: VLAN TCI to insert 267 * 268 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest 269 */ 270 static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, 271 u16 vlan_tci) 272 { 273 skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci; 274 return skb; 275 } 276 277 #define HAVE_VLAN_PUT_TAG 278 279 /** 280 * vlan_put_tag - inserts VLAN tag according to device features 281 * @skb: skbuff to tag 282 * @vlan_tci: VLAN TCI to insert 283 * 284 * Assumes skb->dev is the target that will xmit this frame. 285 * Returns a VLAN tagged skb. 286 */ 287 static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, u16 vlan_tci) 288 { 289 if (skb->dev->features & NETIF_F_HW_VLAN_TX) { 290 return __vlan_hwaccel_put_tag(skb, vlan_tci); 291 } else { 292 return __vlan_put_tag(skb, vlan_tci); 293 } 294 } 295 296 /** 297 * __vlan_get_tag - get the VLAN ID that is part of the payload 298 * @skb: skbuff to query 299 * @vlan_tci: buffer to store vlaue 300 * 301 * Returns error if the skb is not of VLAN type 302 */ 303 static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) 304 { 305 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data; 306 307 if (veth->h_vlan_proto != htons(ETH_P_8021Q)) { 308 return -EINVAL; 309 } 310 311 *vlan_tci = ntohs(veth->h_vlan_TCI); 312 return 0; 313 } 314 315 /** 316 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[] 317 * @skb: skbuff to query 318 * @vlan_tci: buffer to store vlaue 319 * 320 * Returns error if @skb->vlan_tci is not set correctly 321 */ 322 static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb, 323 u16 *vlan_tci) 324 { 325 if (vlan_tx_tag_present(skb)) { 326 *vlan_tci = vlan_tx_tag_get(skb); 327 return 0; 328 } else { 329 *vlan_tci = 0; 330 return -EINVAL; 331 } 332 } 333 334 #define HAVE_VLAN_GET_TAG 335 336 /** 337 * vlan_get_tag - get the VLAN ID from the skb 338 * @skb: skbuff to query 339 * @vlan_tci: buffer to store vlaue 340 * 341 * Returns error if the skb is not VLAN tagged 342 */ 343 static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) 344 { 345 if (skb->dev->features & NETIF_F_HW_VLAN_TX) { 346 return __vlan_hwaccel_get_tag(skb, vlan_tci); 347 } else { 348 return __vlan_get_tag(skb, vlan_tci); 349 } 350 } 351 352 /** 353 * vlan_get_protocol - get protocol EtherType. 354 * @skb: skbuff to query 355 * 356 * Returns the EtherType of the packet, regardless of whether it is 357 * vlan encapsulated (normal or hardware accelerated) or not. 358 */ 359 static inline __be16 vlan_get_protocol(const struct sk_buff *skb) 360 { 361 __be16 protocol = 0; 362 363 if (vlan_tx_tag_present(skb) || 364 skb->protocol != cpu_to_be16(ETH_P_8021Q)) 365 protocol = skb->protocol; 366 else { 367 __be16 proto, *protop; 368 protop = skb_header_pointer(skb, offsetof(struct vlan_ethhdr, 369 h_vlan_encapsulated_proto), 370 sizeof(proto), &proto); 371 if (likely(protop)) 372 protocol = *protop; 373 } 374 375 return protocol; 376 } 377 #endif /* __KERNEL__ */ 378 379 /* VLAN IOCTLs are found in sockios.h */ 380 381 /* Passed in vlan_ioctl_args structure to determine behaviour. */ 382 enum vlan_ioctl_cmds { 383 ADD_VLAN_CMD, 384 DEL_VLAN_CMD, 385 SET_VLAN_INGRESS_PRIORITY_CMD, 386 SET_VLAN_EGRESS_PRIORITY_CMD, 387 GET_VLAN_INGRESS_PRIORITY_CMD, 388 GET_VLAN_EGRESS_PRIORITY_CMD, 389 SET_VLAN_NAME_TYPE_CMD, 390 SET_VLAN_FLAG_CMD, 391 GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */ 392 GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */ 393 }; 394 395 enum vlan_flags { 396 VLAN_FLAG_REORDER_HDR = 0x1, 397 VLAN_FLAG_GVRP = 0x2, 398 VLAN_FLAG_LOOSE_BINDING = 0x4, 399 }; 400 401 enum vlan_name_types { 402 VLAN_NAME_TYPE_PLUS_VID, /* Name will look like: vlan0005 */ 403 VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like: eth1.0005 */ 404 VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like: vlan5 */ 405 VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like: eth0.5 */ 406 VLAN_NAME_TYPE_HIGHEST 407 }; 408 409 struct vlan_ioctl_args { 410 int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */ 411 char device1[24]; 412 413 union { 414 char device2[24]; 415 int VID; 416 unsigned int skb_priority; 417 unsigned int name_type; 418 unsigned int bind_type; 419 unsigned int flag; /* Matches vlan_dev_info flags */ 420 } u; 421 422 short vlan_qos; 423 }; 424 425 #endif /* !(_LINUX_IF_VLAN_H_) */ 426