LXR linux/include/linux/if

   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 */
  38struct 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 */
  51struct 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
  61static 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_PRIO_MASK          0xe000 /* Priority Code Point */
  67#define VLAN_PRIO_SHIFT         13
  68#define VLAN_CFI_MASK           0x1000 /* Canonical Format Indicator */
  69#define VLAN_TAG_PRESENT        VLAN_CFI_MASK
  70#define VLAN_VID_MASK           0x0fff /* VLAN Identifier */
  71
  72/* found in socket.c */
  73extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
  74
  75/* if this changes, algorithm will have to be reworked because this
  76 * depends on completely exhausting the VLAN identifier space.  Thus
  77 * it gives constant time look-up, but in many cases it wastes memory.
  78 */
  79#define VLAN_GROUP_ARRAY_LEN          4096
  80#define VLAN_GROUP_ARRAY_SPLIT_PARTS  8
  81#define VLAN_GROUP_ARRAY_PART_LEN     (VLAN_GROUP_ARRAY_LEN/VLAN_GROUP_ARRAY_SPLIT_PARTS)
  82
  83struct vlan_group {
  84        struct net_device       *real_dev; /* The ethernet(like) device
  85                                            * the vlan is attached to.
  86                                            */
  87        unsigned int            nr_vlans;
  88        int                     killall;
  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
  94static 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
 102static 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#define vlan_tx_tag_present(__skb)      ((__skb)->vlan_tci & VLAN_TAG_PRESENT)
 114#define vlan_tx_tag_get(__skb)          ((__skb)->vlan_tci & ~VLAN_TAG_PRESENT)
 115
 116#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
 117extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
 118extern u16 vlan_dev_vlan_id(const struct net_device *dev);
 119
 120extern int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
 121                             u16 vlan_tci, int polling);
 122extern int vlan_hwaccel_do_receive(struct sk_buff *skb);
 123extern gro_result_t
 124vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
 125                 unsigned int vlan_tci, struct sk_buff *skb);
 126extern gro_result_t
 127vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
 128               unsigned int vlan_tci);
 129
 130#else
 131static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
 132{
 133        BUG();
 134        return NULL;
 135}
 136
 137static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
 138{
 139        BUG();
 140        return 0;
 141}
 142
 143static inline int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
 144                                    u16 vlan_tci, int polling)
 145{
 146        BUG();
 147        return NET_XMIT_SUCCESS;
 148}
 149
 150static inline int vlan_hwaccel_do_receive(struct sk_buff *skb)
 151{
 152        return 0;
 153}
 154
 155static inline gro_result_t
 156vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
 157                 unsigned int vlan_tci, struct sk_buff *skb)
 158{
 159        return GRO_DROP;
 160}
 161
 162static inline gro_result_t
 163vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
 164               unsigned int vlan_tci)
 165{
 166        return GRO_DROP;
 167}
 168#endif
 169
 170/**
 171 * vlan_hwaccel_rx - netif_rx wrapper for VLAN RX acceleration
 172 * @skb: buffer
 173 * @grp: vlan group
 174 * @vlan_tci: VLAN TCI as received from the card
 175 */
 176static inline int vlan_hwaccel_rx(struct sk_buff *skb,
 177                                  struct vlan_group *grp,
 178                                  u16 vlan_tci)
 179{
 180        return __vlan_hwaccel_rx(skb, grp, vlan_tci, 0);
 181}
 182
 183/**
 184 * vlan_hwaccel_receive_skb - netif_receive_skb wrapper for VLAN RX acceleration
 185 * @skb: buffer
 186 * @grp: vlan group
 187 * @vlan_tci: VLAN TCI as received from the card
 188 */
 189static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
 190                                           struct vlan_group *grp,
 191                                           u16 vlan_tci)
 192{
 193        return __vlan_hwaccel_rx(skb, grp, vlan_tci, 1);
 194}
 195
 196/**
 197 * __vlan_put_tag - regular VLAN tag inserting
 198 * @skb: skbuff to tag
 199 * @vlan_tci: VLAN TCI to insert
 200 *
 201 * Inserts the VLAN tag into @skb as part of the payload
 202 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
 203 *
 204 * Following the skb_unshare() example, in case of error, the calling function
 205 * doesn't have to worry about freeing the original skb.
 206 */
 207static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, u16 vlan_tci)
 208{
 209        struct vlan_ethhdr *veth;
 210
 211        if (skb_cow_head(skb, VLAN_HLEN) < 0) {
 212                kfree_skb(skb);
 213                return NULL;
 214        }
 215        veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
 216
 217        /* Move the mac addresses to the beginning of the new header. */
 218        memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);
 219        skb->mac_header -= VLAN_HLEN;
 220
 221        /* first, the ethernet type */
 222        veth->h_vlan_proto = htons(ETH_P_8021Q);
 223
 224        /* now, the TCI */
 225        veth->h_vlan_TCI = htons(vlan_tci);
 226
 227        skb->protocol = htons(ETH_P_8021Q);
 228
 229        return skb;
 230}
 231
 232/**
 233 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
 234 * @skb: skbuff to tag
 235 * @vlan_tci: VLAN TCI to insert
 236 *
 237 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
 238 */
 239static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb,
 240                                                     u16 vlan_tci)
 241{
 242        skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci;
 243        return skb;
 244}
 245
 246#define HAVE_VLAN_PUT_TAG
 247
 248/**
 249 * vlan_put_tag - inserts VLAN tag according to device features
 250 * @skb: skbuff to tag
 251 * @vlan_tci: VLAN TCI to insert
 252 *
 253 * Assumes skb->dev is the target that will xmit this frame.
 254 * Returns a VLAN tagged skb.
 255 */
 256static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, u16 vlan_tci)
 257{
 258        if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
 259                return __vlan_hwaccel_put_tag(skb, vlan_tci);
 260        } else {
 261                return __vlan_put_tag(skb, vlan_tci);
 262        }
 263}
 264
 265/**
 266 * __vlan_get_tag - get the VLAN ID that is part of the payload
 267 * @skb: skbuff to query
 268 * @vlan_tci: buffer to store vlaue
 269 *
 270 * Returns error if the skb is not of VLAN type
 271 */
 272static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
 273{
 274        struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
 275
 276        if (veth->h_vlan_proto != htons(ETH_P_8021Q)) {
 277                return -EINVAL;
 278        }
 279
 280        *vlan_tci = ntohs(veth->h_vlan_TCI);
 281        return 0;
 282}
 283
 284/**
 285 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
 286 * @skb: skbuff to query
 287 * @vlan_tci: buffer to store vlaue
 288 *
 289 * Returns error if @skb->vlan_tci is not set correctly
 290 */
 291static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
 292                                         u16 *vlan_tci)
 293{
 294        if (vlan_tx_tag_present(skb)) {
 295                *vlan_tci = vlan_tx_tag_get(skb);
 296                return 0;
 297        } else {
 298                *vlan_tci = 0;
 299                return -EINVAL;
 300        }
 301}
 302
 303#define HAVE_VLAN_GET_TAG
 304
 305/**
 306 * vlan_get_tag - get the VLAN ID from the skb
 307 * @skb: skbuff to query
 308 * @vlan_tci: buffer to store vlaue
 309 *
 310 * Returns error if the skb is not VLAN tagged
 311 */
 312static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
 313{
 314        if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
 315                return __vlan_hwaccel_get_tag(skb, vlan_tci);
 316        } else {
 317                return __vlan_get_tag(skb, vlan_tci);
 318        }
 319}
 320
 321#endif /* __KERNEL__ */
 322
 323/* VLAN IOCTLs are found in sockios.h */
 324
 325/* Passed in vlan_ioctl_args structure to determine behaviour. */
 326enum vlan_ioctl_cmds {
 327        ADD_VLAN_CMD,
 328        DEL_VLAN_CMD,
 329        SET_VLAN_INGRESS_PRIORITY_CMD,
 330        SET_VLAN_EGRESS_PRIORITY_CMD,
 331        GET_VLAN_INGRESS_PRIORITY_CMD,
 332        GET_VLAN_EGRESS_PRIORITY_CMD,
 333        SET_VLAN_NAME_TYPE_CMD,
 334        SET_VLAN_FLAG_CMD,
 335        GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */
 336        GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */
 337};
 338
 339enum vlan_flags {
 340        VLAN_FLAG_REORDER_HDR   = 0x1,
 341        VLAN_FLAG_GVRP          = 0x2,
 342        VLAN_FLAG_LOOSE_BINDING = 0x4,
 343};
 344
 345enum vlan_name_types {
 346        VLAN_NAME_TYPE_PLUS_VID, /* Name will look like:  vlan0005 */
 347        VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like:  eth1.0005 */
 348        VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like:  vlan5 */
 349        VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like:  eth0.5 */
 350        VLAN_NAME_TYPE_HIGHEST
 351};
 352
 353struct vlan_ioctl_args {
 354        int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
 355        char device1[24];
 356
 357        union {
 358                char device2[24];
 359                int VID;
 360                unsigned int skb_priority;
 361                unsigned int name_type;
 362                unsigned int bind_type;
 363                unsigned int flag; /* Matches vlan_dev_info flags */
 364        } u;
 365
 366        short vlan_qos;   
 367};
 368
 369#endif /* !(_LINUX_IF_VLAN_H_) */
 370