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 20 #define VLAN_HLEN 4 /* The additional bytes (on top of the Ethernet header) 21 * that VLAN requires. 22 */ 23 #define VLAN_ETH_ALEN 6 /* Octets in one ethernet addr */ 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 (always 0x8100) 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_VID_MASK 0xfff 67 68 /* found in socket.c */ 69 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *)); 70 71 /* if this changes, algorithm will have to be reworked because this 72 * depends on completely exhausting the VLAN identifier space. Thus 73 * it gives constant time look-up, but in many cases it wastes memory. 74 */ 75 #define VLAN_GROUP_ARRAY_LEN 4096 76 #define VLAN_GROUP_ARRAY_SPLIT_PARTS 8 77 #define VLAN_GROUP_ARRAY_PART_LEN (VLAN_GROUP_ARRAY_LEN/VLAN_GROUP_ARRAY_SPLIT_PARTS) 78 79 struct vlan_group { 80 struct net_device *real_dev; /* The ethernet(like) device 81 * the vlan is attached to. 82 */ 83 unsigned int nr_vlans; 84 struct hlist_node hlist; /* linked list */ 85 struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS]; 86 struct rcu_head rcu; 87 }; 88 89 static inline struct net_device *vlan_group_get_device(struct vlan_group *vg, 90 u16 vlan_id) 91 { 92 struct net_device **array; 93 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN]; 94 return array ? array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] : NULL; 95 } 96 97 static inline void vlan_group_set_device(struct vlan_group *vg, 98 u16 vlan_id, 99 struct net_device *dev) 100 { 101 struct net_device **array; 102 if (!vg) 103 return; 104 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN]; 105 array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] = dev; 106 } 107 108 #define vlan_tx_tag_present(__skb) ((__skb)->vlan_tci) 109 #define vlan_tx_tag_get(__skb) ((__skb)->vlan_tci) 110 111 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) 112 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev); 113 extern u16 vlan_dev_vlan_id(const struct net_device *dev); 114 115 extern int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp, 116 u16 vlan_tci, int polling); 117 extern int vlan_hwaccel_do_receive(struct sk_buff *skb); 118 extern int vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp, 119 unsigned int vlan_tci, struct sk_buff *skb); 120 extern int vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp, 121 unsigned int vlan_tci); 122 123 #else 124 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev) 125 { 126 BUG(); 127 return NULL; 128 } 129 130 static inline u16 vlan_dev_vlan_id(const struct net_device *dev) 131 { 132 BUG(); 133 return 0; 134 } 135 136 static inline int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp, 137 u16 vlan_tci, int polling) 138 { 139 BUG(); 140 return NET_XMIT_SUCCESS; 141 } 142 143 static inline int vlan_hwaccel_do_receive(struct sk_buff *skb) 144 { 145 return 0; 146 } 147 148 static inline int vlan_gro_receive(struct napi_struct *napi, 149 struct vlan_group *grp, 150 unsigned int vlan_tci, struct sk_buff *skb) 151 { 152 return NET_RX_DROP; 153 } 154 155 static inline int vlan_gro_frags(struct napi_struct *napi, 156 struct vlan_group *grp, unsigned int vlan_tci) 157 { 158 return NET_RX_DROP; 159 } 160 #endif 161 162 /** 163 * vlan_hwaccel_rx - netif_rx wrapper for VLAN RX acceleration 164 * @skb: buffer 165 * @grp: vlan group 166 * @vlan_tci: VLAN TCI as received from the card 167 */ 168 static inline int vlan_hwaccel_rx(struct sk_buff *skb, 169 struct vlan_group *grp, 170 u16 vlan_tci) 171 { 172 return __vlan_hwaccel_rx(skb, grp, vlan_tci, 0); 173 } 174 175 /** 176 * vlan_hwaccel_receive_skb - netif_receive_skb wrapper for VLAN RX acceleration 177 * @skb: buffer 178 * @grp: vlan group 179 * @vlan_tci: VLAN TCI as received from the card 180 */ 181 static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb, 182 struct vlan_group *grp, 183 u16 vlan_tci) 184 { 185 return __vlan_hwaccel_rx(skb, grp, vlan_tci, 1); 186 } 187 188 /** 189 * __vlan_put_tag - regular VLAN tag inserting 190 * @skb: skbuff to tag 191 * @vlan_tci: VLAN TCI to insert 192 * 193 * Inserts the VLAN tag into @skb as part of the payload 194 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed. 195 * 196 * Following the skb_unshare() example, in case of error, the calling function 197 * doesn't have to worry about freeing the original skb. 198 */ 199 static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, u16 vlan_tci) 200 { 201 struct vlan_ethhdr *veth; 202 203 if (skb_cow_head(skb, VLAN_HLEN) < 0) { 204 kfree_skb(skb); 205 return NULL; 206 } 207 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN); 208 209 /* Move the mac addresses to the beginning of the new header. */ 210 memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN); 211 skb->mac_header -= VLAN_HLEN; 212 213 /* first, the ethernet type */ 214 veth->h_vlan_proto = htons(ETH_P_8021Q); 215 216 /* now, the TCI */ 217 veth->h_vlan_TCI = htons(vlan_tci); 218 219 skb->protocol = htons(ETH_P_8021Q); 220 221 return skb; 222 } 223 224 /** 225 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting 226 * @skb: skbuff to tag 227 * @vlan_tci: VLAN TCI to insert 228 * 229 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest 230 */ 231 static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, 232 u16 vlan_tci) 233 { 234 skb->vlan_tci = vlan_tci; 235 return skb; 236 } 237 238 #define HAVE_VLAN_PUT_TAG 239 240 /** 241 * vlan_put_tag - inserts VLAN tag according to device features 242 * @skb: skbuff to tag 243 * @vlan_tci: VLAN TCI to insert 244 * 245 * Assumes skb->dev is the target that will xmit this frame. 246 * Returns a VLAN tagged skb. 247 */ 248 static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, u16 vlan_tci) 249 { 250 if (skb->dev->features & NETIF_F_HW_VLAN_TX) { 251 return __vlan_hwaccel_put_tag(skb, vlan_tci); 252 } else { 253 return __vlan_put_tag(skb, vlan_tci); 254 } 255 } 256 257 /** 258 * __vlan_get_tag - get the VLAN ID that is part of the payload 259 * @skb: skbuff to query 260 * @vlan_tci: buffer to store vlaue 261 * 262 * Returns error if the skb is not of VLAN type 263 */ 264 static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) 265 { 266 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data; 267 268 if (veth->h_vlan_proto != htons(ETH_P_8021Q)) { 269 return -EINVAL; 270 } 271 272 *vlan_tci = ntohs(veth->h_vlan_TCI); 273 return 0; 274 } 275 276 /** 277 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[] 278 * @skb: skbuff to query 279 * @vlan_tci: buffer to store vlaue 280 * 281 * Returns error if @skb->vlan_tci is not set correctly 282 */ 283 static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb, 284 u16 *vlan_tci) 285 { 286 if (vlan_tx_tag_present(skb)) { 287 *vlan_tci = skb->vlan_tci; 288 return 0; 289 } else { 290 *vlan_tci = 0; 291 return -EINVAL; 292 } 293 } 294 295 #define HAVE_VLAN_GET_TAG 296 297 /** 298 * vlan_get_tag - get the VLAN ID from the skb 299 * @skb: skbuff to query 300 * @vlan_tci: buffer to store vlaue 301 * 302 * Returns error if the skb is not VLAN tagged 303 */ 304 static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) 305 { 306 if (skb->dev->features & NETIF_F_HW_VLAN_TX) { 307 return __vlan_hwaccel_get_tag(skb, vlan_tci); 308 } else { 309 return __vlan_get_tag(skb, vlan_tci); 310 } 311 } 312 313 #endif /* __KERNEL__ */ 314 315 /* VLAN IOCTLs are found in sockios.h */ 316 317 /* Passed in vlan_ioctl_args structure to determine behaviour. */ 318 enum vlan_ioctl_cmds { 319 ADD_VLAN_CMD, 320 DEL_VLAN_CMD, 321 SET_VLAN_INGRESS_PRIORITY_CMD, 322 SET_VLAN_EGRESS_PRIORITY_CMD, 323 GET_VLAN_INGRESS_PRIORITY_CMD, 324 GET_VLAN_EGRESS_PRIORITY_CMD, 325 SET_VLAN_NAME_TYPE_CMD, 326 SET_VLAN_FLAG_CMD, 327 GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */ 328 GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */ 329 }; 330 331 enum vlan_flags { 332 VLAN_FLAG_REORDER_HDR = 0x1, 333 VLAN_FLAG_GVRP = 0x2, 334 }; 335 336 enum vlan_name_types { 337 VLAN_NAME_TYPE_PLUS_VID, /* Name will look like: vlan0005 */ 338 VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like: eth1.0005 */ 339 VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like: vlan5 */ 340 VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like: eth0.5 */ 341 VLAN_NAME_TYPE_HIGHEST 342 }; 343 344 struct vlan_ioctl_args { 345 int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */ 346 char device1[24]; 347 348 union { 349 char device2[24]; 350 int VID; 351 unsigned int skb_priority; 352 unsigned int name_type; 353 unsigned int bind_type; 354 unsigned int flag; /* Matches vlan_dev_info flags */ 355 } u; 356 357 short vlan_qos; 358 }; 359 360 #endif /* !(_LINUX_IF_VLAN_H_) */ 361