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