/*
* 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__
/* externally defined structs */
struct hlist_node;
#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,
unsigned int 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,
unsigned int 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;
}
struct vlan_priority_tci_mapping {
u32 priority;
unsigned short vlan_qos; /* This should be shifted when first set, so we only do it
* at provisioning time.
* ((skb->priority << 13) & 0xE000)
*/
struct vlan_priority_tci_mapping *next;
};
/* Holds information that makes sense if this device is a VLAN device. */
struct vlan_dev_info {
/** This will be the mapping that correlates skb->priority to
* 3 bits of VLAN QOS tags...
*/
unsigned int nr_ingress_mappings;
u32 ingress_priority_map[8];
unsigned int nr_egress_mappings;
struct vlan_priority_tci_mapping *egress_priority_map[16]; /* hash table */
unsigned short vlan_id; /* The VLAN Identifier for this interface. */
unsigned short flags; /* (1 << 0) re_order_header This option will cause the
* VLAN code to move around the ethernet header on
* ingress to make the skb look **exactly** like it
* came in from an ethernet port. This destroys some of
* the VLAN information in the skb, but it fixes programs
* like DHCP that use packet-filtering and don't understand
* 802.1Q
*/
struct net_device *real_dev; /* the underlying device/interface */
unsigned char real_dev_addr[ETH_ALEN];
struct proc_dir_entry *dent; /* Holds the proc data */
unsigned long cnt_inc_headroom_on_tx; /* How many times did we have to grow the skb on TX. */
unsigned long cnt_encap_on_xmit; /* How many times did we have to encapsulate the skb on TX. */
};
static inline struct vlan_dev_info *vlan_dev_info(const struct net_device *dev)
{
return netdev_priv(dev);
}
/* inline functions */
static inline __u32 vlan_get_ingress_priority(struct net_device *dev,
unsigned short vlan_tag)
{
struct vlan_dev_info *vip = vlan_dev_info(dev);
return vip->ingress_priority_map[(vlan_tag >> 13) & 0x7];
}
/* VLAN tx hw acceleration helpers. */
struct vlan_skb_tx_cookie {
u32 magic;
u32 vlan_tag;
};
#define VLAN_TX_COOKIE_MAGIC 0x564c414e /* "VLAN" in ascii. */
#define VLAN_TX_SKB_CB(__skb) ((struct vlan_skb_tx_cookie *)&((__skb)->cb[0]))
#define vlan_tx_tag_present(__skb) \
(VLAN_TX_SKB_CB(__skb)->magic == VLAN_TX_COOKIE_MAGIC)
#define vlan_tx_tag_get(__skb) (VLAN_TX_SKB_CB(__skb)->vlan_tag)
/* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
static inline int __vlan_hwaccel_rx(struct sk_buff *skb,
struct vlan_group *grp,
unsigned short vlan_tag, int polling)
{
struct net_device_stats *stats;
if (skb_bond_should_drop(skb)) {
dev_kfree_skb_any(skb);
return NET_RX_DROP;
}
skb->dev = vlan_group_get_device(grp, vlan_tag & VLAN_VID_MASK);
if (skb->dev == NULL) {
dev_kfree_skb_any(skb);
/* Not NET_RX_DROP, this is not being dropped
* due to congestion.
*/
return 0;
}
skb->dev->last_rx = jiffies;
stats = &skb->dev->stats;
stats->rx_packets++;
stats->rx_bytes += skb->len;
skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tag);
switch (skb->pkt_type) {
case PACKET_BROADCAST:
break;
case PACKET_MULTICAST:
stats->multicast++;
break;
case PACKET_OTHERHOST:
/* Our lower layer thinks this is not local, let's make sure.
* This allows the VLAN to have a different MAC than the underlying
* device, and still route correctly.
*/
if (!compare_ether_addr(eth_hdr(skb)->h_dest,
skb->dev->dev_addr))
skb->pkt_type = PACKET_HOST;
break;
};
return (polling ? netif_receive_skb(skb) : netif_rx(skb));
}
static inline int vlan_hwaccel_rx(struct sk_buff *skb,
struct vlan_group *grp,
unsigned short vlan_tag)
{
return __vlan_hwaccel_rx(skb, grp, vlan_tag, 0);
}
static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
struct vlan_group *grp,
unsigned short vlan_tag)
{
return __vlan_hwaccel_rx(skb, grp, vlan_tag, 1);
}
/**
* __vlan_put_tag - regular VLAN tag inserting
* @skb: skbuff to tag
* @tag: VLAN tag 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, unsigned short tag)
{
struct vlan_ethhdr *veth;
if (skb_headroom(skb) < VLAN_HLEN) {
struct sk_buff *sk_tmp = skb;
skb = skb_realloc_headroom(sk_tmp, VLAN_HLEN);
kfree_skb(sk_tmp);
if (!skb) {
printk(KERN_ERR "vlan: failed to realloc headroom\n");
return NULL;
}
} else {
skb = skb_unshare(skb, GFP_ATOMIC);
if (!skb) {
printk(KERN_ERR "vlan: failed to unshare skbuff\n");
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);
/* first, the ethernet type */
veth->h_vlan_proto = htons(ETH_P_8021Q);
/* now, the tag */
veth->h_vlan_TCI = htons(tag);
skb->protocol = htons(ETH_P_8021Q);
skb->mac_header -= VLAN_HLEN;
skb->network_header -= VLAN_HLEN;
return skb;
}
/**
* __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
* @skb: skbuff to tag
* @tag: VLAN tag to insert
*
* Puts the VLAN tag in @skb->cb[] and lets the device do the rest
*/
static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, unsigned short tag)
{
struct vlan_skb_tx_cookie *cookie;
cookie = VLAN_TX_SKB_CB(skb);
cookie->magic = VLAN_TX_COOKIE_MAGIC;
cookie->vlan_tag = tag;
return skb;
}
#define HAVE_VLAN_PUT_TAG
/**
* vlan_put_tag - inserts VLAN tag according to device features
* @skb: skbuff to tag
* @tag: VLAN tag 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, unsigned short tag)
{
if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
return __vlan_hwaccel_put_tag(skb, tag);
} else {
return __vlan_put_tag(skb, tag);
}
}
/**
* __vlan_get_tag - get the VLAN ID that is part of the payload
* @skb: skbuff to query
* @tag: 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, unsigned short *tag)
{
struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
if (veth->h_vlan_proto != htons(ETH_P_8021Q)) {
return -EINVAL;
}
*tag = ntohs(veth->h_vlan_TCI);
return 0;
}
/**
* __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
* @skb: skbuff to query
* @tag: buffer to store vlaue
*
* Returns error if @skb->cb[] is not set correctly
*/
static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
unsigned short *tag)
{
struct vlan_skb_tx_cookie *cookie;
cookie = VLAN_TX_SKB_CB(skb);
if (cookie->magic == VLAN_TX_COOKIE_MAGIC) {
*tag = cookie->vlan_tag;
return 0;
} else {
*tag = 0;
return -EINVAL;
}
}
#define HAVE_VLAN_GET_TAG
/**
* vlan_get_tag - get the VLAN ID from the skb
* @skb: skbuff to query
* @tag: buffer to store vlaue
*
* Returns error if the skb is not VLAN tagged
*/
static inline int vlan_get_tag(const struct sk_buff *skb, unsigned short *tag)
{
if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
return __vlan_hwaccel_get_tag(skb, tag);
} else {
return __vlan_get_tag(skb, tag);
}
}
#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,
};
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_) */
