1 /* 2 * VLAN An implementation of 802.1Q VLAN tagging. 3 * 4 * Authors: Ben Greear <[email protected]> 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); 118 119 #else 120 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev) 121 { 122 BUG(); 123 return NULL; 124 } 125 126 static inline u16 vlan_dev_vlan_id(const struct net_device *dev) 127 { 128 BUG(); 129 return 0; 130 } 131 132 static inline int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp, 133 u16 vlan_tci, int polling) 134 { 135 BUG(); 136 return NET_XMIT_SUCCESS; 137 } 138 139 static inline int vlan_hwaccel_do_receive(struct sk_buff *skb) 140 { 141 return 0; 142 } 143 #endif 144 145 /** 146 * vlan_hwaccel_rx - netif_rx wrapper for VLAN RX acceleration 147 * @skb: buffer 148 * @grp: vlan group 149 * @vlan_tci: VLAN TCI as received from the card 150 */ 151 static inline int vlan_hwaccel_rx(struct sk_buff *skb, 152 struct vlan_group *grp, 153 u16 vlan_tci) 154 { 155 return __vlan_hwaccel_rx(skb, grp, vlan_tci, 0); 156 } 157 158 /** 159 * vlan_hwaccel_receive_skb - netif_receive_skb wrapper for VLAN RX acceleration 160 * @skb: buffer 161 * @grp: vlan group 162 * @vlan_tci: VLAN TCI as received from the card 163 */ 164 static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb, 165 struct vlan_group *grp, 166 u16 vlan_tci) 167 { 168 return __vlan_hwaccel_rx(skb, grp, vlan_tci, 1); 169 } 170 171 /** 172 * __vlan_put_tag - regular VLAN tag inserting 173 * @skb: skbuff to tag 174 * @vlan_tci: VLAN TCI to insert 175 * 176 * Inserts the VLAN tag into @skb as part of the payload 177 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed. 178 * 179 * Following the skb_unshare() example, in case of error, the calling function 180 * doesn't have to worry about freeing the original skb. 181 */ 182 static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, u16 vlan_tci) 183 { 184 struct vlan_ethhdr *veth; 185 186 if (skb_cow_head(skb, VLAN_HLEN) < 0) { 187 kfree_skb(skb); 188 return NULL; 189 } 190 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN); 191 192 /* Move the mac addresses to the beginning of the new header. */ 193 memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN); 194 195 /* first, the ethernet type */ 196 veth->h_vlan_proto = htons(ETH_P_8021Q); 197 198 /* now, the TCI */ 199 veth->h_vlan_TCI = htons(vlan_tci); 200 201 skb->protocol = htons(ETH_P_8021Q); 202 203 return skb; 204 } 205 206 /** 207 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting 208 * @skb: skbuff to tag 209 * @vlan_tci: VLAN TCI to insert 210 * 211 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest 212 */ 213 static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, 214 u16 vlan_tci) 215 { 216 skb->vlan_tci = vlan_tci; 217 return skb; 218 } 219 220 #define HAVE_VLAN_PUT_TAG 221 222 /** 223 * vlan_put_tag - inserts VLAN tag according to device features 224 * @skb: skbuff to tag 225 * @vlan_tci: VLAN TCI to insert 226 * 227 * Assumes skb->dev is the target that will xmit this frame. 228 * Returns a VLAN tagged skb. 229 */ 230 static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, u16 vlan_tci) 231 { 232 if (skb->dev->features & NETIF_F_HW_VLAN_TX) { 233 return __vlan_hwaccel_put_tag(skb, vlan_tci); 234 } else { 235 return __vlan_put_tag(skb, vlan_tci); 236 } 237 } 238 239 /** 240 * __vlan_get_tag - get the VLAN ID that is part of the payload 241 * @skb: skbuff to query 242 * @vlan_tci: buffer to store vlaue 243 * 244 * Returns error if the skb is not of VLAN type 245 */ 246 static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) 247 { 248 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data; 249 250 if (veth->h_vlan_proto != htons(ETH_P_8021Q)) { 251 return -EINVAL; 252 } 253 254 *vlan_tci = ntohs(veth->h_vlan_TCI); 255 return 0; 256 } 257 258 /** 259 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[] 260 * @skb: skbuff to query 261 * @vlan_tci: buffer to store vlaue 262 * 263 * Returns error if @skb->vlan_tci is not set correctly 264 */ 265 static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb, 266 u16 *vlan_tci) 267 { 268 if (vlan_tx_tag_present(skb)) { 269 *vlan_tci = skb->vlan_tci; 270 return 0; 271 } else { 272 *vlan_tci = 0; 273 return -EINVAL; 274 } 275 } 276 277 #define HAVE_VLAN_GET_TAG 278 279 /** 280 * vlan_get_tag - get the VLAN ID from the skb 281 * @skb: skbuff to query 282 * @vlan_tci: buffer to store vlaue 283 * 284 * Returns error if the skb is not VLAN tagged 285 */ 286 static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci) 287 { 288 if (skb->dev->features & NETIF_F_HW_VLAN_TX) { 289 return __vlan_hwaccel_get_tag(skb, vlan_tci); 290 } else { 291 return __vlan_get_tag(skb, vlan_tci); 292 } 293 } 294 295 #endif /* __KERNEL__ */ 296 297 /* VLAN IOCTLs are found in sockios.h */ 298 299 /* Passed in vlan_ioctl_args structure to determine behaviour. */ 300 enum vlan_ioctl_cmds { 301 ADD_VLAN_CMD, 302 DEL_VLAN_CMD, 303 SET_VLAN_INGRESS_PRIORITY_CMD, 304 SET_VLAN_EGRESS_PRIORITY_CMD, 305 GET_VLAN_INGRESS_PRIORITY_CMD, 306 GET_VLAN_EGRESS_PRIORITY_CMD, 307 SET_VLAN_NAME_TYPE_CMD, 308 SET_VLAN_FLAG_CMD, 309 GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */ 310 GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */ 311 }; 312 313 enum vlan_flags { 314 VLAN_FLAG_REORDER_HDR = 0x1, 315 VLAN_FLAG_GVRP = 0x2, 316 }; 317 318 enum vlan_name_types { 319 VLAN_NAME_TYPE_PLUS_VID, /* Name will look like: vlan0005 */ 320 VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like: eth1.0005 */ 321 VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like: vlan5 */ 322 VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like: eth0.5 */ 323 VLAN_NAME_TYPE_HIGHEST 324 }; 325 326 struct vlan_ioctl_args { 327 int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */ 328 char device1[24]; 329 330 union { 331 char device2[24]; 332 int VID; 333 unsigned int skb_priority; 334 unsigned int name_type; 335 unsigned int bind_type; 336 unsigned int flag; /* Matches vlan_dev_info flags */ 337 } u; 338 339 short vlan_qos; 340 }; 341 342 #endif /* !(_LINUX_IF_VLAN_H_) */ 343