if_vlan.h 9.5 KB

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