/*
 * VLAN         An implementation of 802.1Q VLAN tagging.
 *
 * Authors:     Ben Greear <greearb@candelatech.com>
 *
 *              This program is free software; you can redistribute it and/or
 *              modify it under the terms of the GNU General Public License
 *              as published by the Free Software Foundation; either version
 *              2 of the License, or (at your option) any later version.
 *
 */

#ifndef _LINUX_IF_VLAN_H_
#define _LINUX_IF_VLAN_H_

#ifdef __KERNEL__
#include <linux/netdevice.h>
#include <linux/etherdevice.h>

#define VLAN_HLEN       4               /* The additional bytes (on top of the Ethernet header)
                                         * that VLAN requires.
                                         */
#define VLAN_ETH_ALEN   6               /* Octets in one ethernet addr   */
#define VLAN_ETH_HLEN   18              /* Total octets in header.       */
#define VLAN_ETH_ZLEN   64              /* Min. octets in frame sans FCS */

/*
 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
 */
#define VLAN_ETH_DATA_LEN       1500    /* Max. octets in payload        */
#define VLAN_ETH_FRAME_LEN      1518    /* Max. octets in frame sans FCS */

/*
 *      struct vlan_hdr - vlan header
 *      @h_vlan_TCI: priority and VLAN ID
 *      @h_vlan_encapsulated_proto: packet type ID or len
 */
struct vlan_hdr {
        __be16  h_vlan_TCI;
        __be16  h_vlan_encapsulated_proto;
};

/**
 *      struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr)
 *      @h_dest: destination ethernet address
 *      @h_source: source ethernet address
 *      @h_vlan_proto: ethernet protocol (always 0x8100)
 *      @h_vlan_TCI: priority and VLAN ID
 *      @h_vlan_encapsulated_proto: packet type ID or len
 */
struct vlan_ethhdr {
        unsigned char   h_dest[ETH_ALEN];
        unsigned char   h_source[ETH_ALEN];
        __be16          h_vlan_proto;
        __be16          h_vlan_TCI;
        __be16          h_vlan_encapsulated_proto;
};

#include <linux/skbuff.h>

static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
{
        return (struct vlan_ethhdr *)skb_mac_header(skb);
}

#define VLAN_VID_MASK   0xfff

/* found in socket.c */
extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));

/* if this changes, algorithm will have to be reworked because this
 * depends on completely exhausting the VLAN identifier space.  Thus
 * it gives constant time look-up, but in many cases it wastes memory.
 */
#define VLAN_GROUP_ARRAY_LEN          4096
#define VLAN_GROUP_ARRAY_SPLIT_PARTS  8
#define VLAN_GROUP_ARRAY_PART_LEN     (VLAN_GROUP_ARRAY_LEN/VLAN_GROUP_ARRAY_SPLIT_PARTS)

struct vlan_group {
        struct net_device       *real_dev; /* The ethernet(like) device
                                            * the vlan is attached to.
                                            */
        unsigned int            nr_vlans;
        struct hlist_node       hlist;  /* linked list */
        struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS];
        struct rcu_head         rcu;
};

static inline struct net_device *vlan_group_get_device(struct vlan_group *vg,
                                                       u16 vlan_id)
{
        struct net_device **array;
        array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
        return array ? array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] : NULL;
}

static inline void vlan_group_set_device(struct vlan_group *vg,
                                         u16 vlan_id,
                                         struct net_device *dev)
{
        struct net_device **array;
        if (!vg)
                return;
        array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
        array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] = dev;
}

#define vlan_tx_tag_present(__skb)      ((__skb)->vlan_tci)
#define vlan_tx_tag_get(__skb)          ((__skb)->vlan_tci)

#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
extern u16 vlan_dev_vlan_id(const struct net_device *dev);

extern int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
                             u16 vlan_tci, int polling);
extern int vlan_hwaccel_do_receive(struct sk_buff *skb);
extern int vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
                            unsigned int vlan_tci, struct sk_buff *skb);
extern int vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
                          unsigned int vlan_tci);

#else
static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
{
        BUG();
        return NULL;
}

static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
{
        BUG();
        return 0;
}

static inline int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
                                    u16 vlan_tci, int polling)
{
        BUG();
        return NET_XMIT_SUCCESS;
}

static inline int vlan_hwaccel_do_receive(struct sk_buff *skb)
{
        return 0;
}

static inline int vlan_gro_receive(struct napi_struct *napi,
                                   struct vlan_group *grp,
                                   unsigned int vlan_tci, struct sk_buff *skb)
{
        return NET_RX_DROP;
}

static inline int vlan_gro_frags(struct napi_struct *napi,
                                 struct vlan_group *grp, unsigned int vlan_tci)
{
        return NET_RX_DROP;
}
#endif

/**
 * vlan_hwaccel_rx - netif_rx wrapper for VLAN RX acceleration
 * @skb: buffer
 * @grp: vlan group
 * @vlan_tci: VLAN TCI as received from the card
 */
static inline int vlan_hwaccel_rx(struct sk_buff *skb,
                                  struct vlan_group *grp,
                                  u16 vlan_tci)
{
        return __vlan_hwaccel_rx(skb, grp, vlan_tci, 0);
}

/**
 * vlan_hwaccel_receive_skb - netif_receive_skb wrapper for VLAN RX acceleration
 * @skb: buffer
 * @grp: vlan group
 * @vlan_tci: VLAN TCI as received from the card
 */
static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
                                           struct vlan_group *grp,
                                           u16 vlan_tci)
{
        return __vlan_hwaccel_rx(skb, grp, vlan_tci, 1);
}

/**
 * __vlan_put_tag - regular VLAN tag inserting
 * @skb: skbuff to tag
 * @vlan_tci: VLAN TCI to insert
 *
 * Inserts the VLAN tag into @skb as part of the payload
 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
 *
 * Following the skb_unshare() example, in case of error, the calling function
 * doesn't have to worry about freeing the original skb.
 */
static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, u16 vlan_tci)
{
        struct vlan_ethhdr *veth;

        if (skb_cow_head(skb, VLAN_HLEN) < 0) {
                kfree_skb(skb);
                return NULL;
        }
        veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);

        /* Move the mac addresses to the beginning of the new header. */
        memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);
        skb->mac_header -= VLAN_HLEN;

        /* first, the ethernet type */
        veth->h_vlan_proto = htons(ETH_P_8021Q);

        /* now, the TCI */
        veth->h_vlan_TCI = htons(vlan_tci);

        skb->protocol = htons(ETH_P_8021Q);

        return skb;
}

/**
 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
 * @skb: skbuff to tag
 * @vlan_tci: VLAN TCI to insert
 *
 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
 */
static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb,
                                                     u16 vlan_tci)
{
        skb->vlan_tci = vlan_tci;
        return skb;
}

#define HAVE_VLAN_PUT_TAG

/**
 * vlan_put_tag - inserts VLAN tag according to device features
 * @skb: skbuff to tag
 * @vlan_tci: VLAN TCI to insert
 *
 * Assumes skb->dev is the target that will xmit this frame.
 * Returns a VLAN tagged skb.
 */
static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, u16 vlan_tci)
{
        if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
                return __vlan_hwaccel_put_tag(skb, vlan_tci);
        } else {
                return __vlan_put_tag(skb, vlan_tci);
        }
}

/**
 * __vlan_get_tag - get the VLAN ID that is part of the payload
 * @skb: skbuff to query
 * @vlan_tci: buffer to store vlaue
 *
 * Returns error if the skb is not of VLAN type
 */
static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
{
        struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;

        if (veth->h_vlan_proto != htons(ETH_P_8021Q)) {
                return -EINVAL;
        }

        *vlan_tci = ntohs(veth->h_vlan_TCI);
        return 0;
}

/**
 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
 * @skb: skbuff to query
 * @vlan_tci: buffer to store vlaue
 *
 * Returns error if @skb->vlan_tci is not set correctly
 */
static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
                                         u16 *vlan_tci)
{
        if (vlan_tx_tag_present(skb)) {
                *vlan_tci = skb->vlan_tci;
                return 0;
        } else {
                *vlan_tci = 0;
                return -EINVAL;
        }
}

#define HAVE_VLAN_GET_TAG

/**
 * vlan_get_tag - get the VLAN ID from the skb
 * @skb: skbuff to query
 * @vlan_tci: buffer to store vlaue
 *
 * Returns error if the skb is not VLAN tagged
 */
static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
{
        if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
                return __vlan_hwaccel_get_tag(skb, vlan_tci);
        } else {
                return __vlan_get_tag(skb, vlan_tci);
        }
}

#endif /* __KERNEL__ */

/* VLAN IOCTLs are found in sockios.h */

/* Passed in vlan_ioctl_args structure to determine behaviour. */
enum vlan_ioctl_cmds {
        ADD_VLAN_CMD,
        DEL_VLAN_CMD,
        SET_VLAN_INGRESS_PRIORITY_CMD,
        SET_VLAN_EGRESS_PRIORITY_CMD,
        GET_VLAN_INGRESS_PRIORITY_CMD,
        GET_VLAN_EGRESS_PRIORITY_CMD,
        SET_VLAN_NAME_TYPE_CMD,
        SET_VLAN_FLAG_CMD,
        GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */
        GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */
};

enum vlan_flags {
        VLAN_FLAG_REORDER_HDR   = 0x1,
        VLAN_FLAG_GVRP          = 0x2,
};

enum vlan_name_types {
        VLAN_NAME_TYPE_PLUS_VID, /* Name will look like:  vlan0005 */
        VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like:  eth1.0005 */
        VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like:  vlan5 */
        VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like:  eth0.5 */
        VLAN_NAME_TYPE_HIGHEST
};

struct vlan_ioctl_args {
        int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
        char device1[24];

        union {
                char device2[24];
                int VID;
                unsigned int skb_priority;
                unsigned int name_type;
                unsigned int bind_type;
                unsigned int flag; /* Matches vlan_dev_info flags */
        } u;

        short vlan_qos;   
};

#endif /* !(_LINUX_IF_VLAN_H_) */