/* -*- linux-c -*-
* INET 802.1Q VLAN
* Ethernet-type device handling.
*
* Authors: Ben Greear <greearb@candelatech.com>
* Please send support related email to: netdev@vger.kernel.org
* VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
*
* Fixes: Mar 22 2001: Martin Bokaemper <mbokaemper@unispherenetworks.com>
* - reset skb->pkt_type on incoming packets when MAC was changed
* - see that changed MAC is saddr for outgoing packets
* Oct 20, 2001: Ard van Breeman:
* - Fix MC-list, finally.
* - Flush MC-list on VLAN destroy.
*
*
* 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.
*/
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/in.h>
#include <linux/init.h>
#include <asm/uaccess.h> /* for copy_from_user */
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <net/datalink.h>
#include <net/p8022.h>
#include <net/arp.h>
#include "vlan.h"
#include "vlanproc.h"
#include <linux/if_vlan.h>
#include <net/ip.h>
/*
* Rebuild the Ethernet MAC header. This is called after an ARP
* (or in future other address resolution) has completed on this
* sk_buff. We now let ARP fill in the other fields.
*
* This routine CANNOT use cached dst->neigh!
* Really, it is used only when dst->neigh is wrong.
*
* TODO: This needs a checkup, I'm ignorant here. --BLG
*/
static int vlan_dev_rebuild_header(struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
switch (veth->h_vlan_encapsulated_proto) {
#ifdef CONFIG_INET
case __constant_htons(ETH_P_IP):
/* TODO: Confirm this will work with VLAN headers... */
return arp_find(veth->h_dest, skb);
#endif
default:
pr_debug("%s: unable to resolve type %X addresses.\n",
dev->name, ntohs(veth->h_vlan_encapsulated_proto));
memcpy(veth->h_source, dev->dev_addr, ETH_ALEN);
break;
}
return 0;
}
static inline struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb)
{
if (vlan_dev_info(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) {
if (skb_shared(skb) || skb_cloned(skb)) {
struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
kfree_skb(skb);
skb = nskb;
}
if (skb) {
/* Lifted from Gleb's VLAN code... */
memmove(skb->data - ETH_HLEN,
skb->data - VLAN_ETH_HLEN, 12);
skb->mac_header += VLAN_HLEN;
}
}
return skb;
}
/*
* Determine the packet's protocol ID. The rule here is that we
* assume 802.3 if the type field is short enough to be a length.
* This is normal practice and works for any 'now in use' protocol.
*
* Also, at this point we assume that we ARE dealing exclusively with
* VLAN packets, or packets that should be made into VLAN packets based
* on a default VLAN ID.
*
* NOTE: Should be similar to ethernet/eth.c.
*
* SANITY NOTE: This method is called when a packet is moving up the stack
* towards userland. To get here, it would have already passed
* through the ethernet/eth.c eth_type_trans() method.
* SANITY NOTE 2: We are referencing to the VLAN_HDR frields, which MAY be
* stored UNALIGNED in the memory. RISC systems don't like
* such cases very much...
* SANITY NOTE 2a: According to Dave Miller & Alexey, it will always be
* aligned, so there doesn't need to be any of the unaligned
* stuff. It has been commented out now... --Ben
*
*/
int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *ptype, struct net_device *orig_dev)
{
unsigned char *rawp;
struct vlan_hdr *vhdr;
unsigned short vid;
struct net_device_stats *stats;
unsigned short vlan_TCI;
__be16 proto;
if (dev->nd_net != &init_net)
goto err_free;
skb = skb_share_check(skb, GFP_ATOMIC);
if (skb == NULL)
goto err_free;
if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
goto err_free;
vhdr = (struct vlan_hdr *)skb->data;
vlan_TCI = ntohs(vhdr->h_vlan_TCI);
vid = (vlan_TCI & VLAN_VID_MASK);
rcu_read_lock();
skb->dev = __find_vlan_dev(dev, vid);
if (!skb->dev) {
pr_debug("%s: ERROR: No net_device for VID: %u on dev: %s\n",
__FUNCTION__, (unsigned int)vid, dev->name);
goto err_unlock;
}
skb->dev->last_rx = jiffies;
stats = &skb->dev->stats;
stats->rx_packets++;
stats->rx_bytes += skb->len;
skb_pull_rcsum(skb, VLAN_HLEN);
skb->priority = vlan_get_ingress_priority(skb->dev,
ntohs(vhdr->h_vlan_TCI));
pr_debug("%s: priority: %u for TCI: %hu\n",
__FUNCTION__, skb->priority, ntohs(vhdr->h_vlan_TCI));
switch (skb->pkt_type) {
case PACKET_BROADCAST: /* Yeah, stats collect these together.. */
/* stats->broadcast ++; // no such counter :-( */
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;
default:
break;
}
/* Was a VLAN packet, grab the encapsulated protocol, which the layer
* three protocols care about.
*/
proto = vhdr->h_vlan_encapsulated_proto;
if (ntohs(proto) >= 1536) {
skb->protocol = proto;
goto recv;
}
/*
* This is a magic hack to spot IPX packets. Older Novell breaks
* the protocol design and runs IPX over 802.3 without an 802.2 LLC
* layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
* won't work for fault tolerant netware but does for the rest.
*/
rawp = skb->data;
if (*(unsigned short *)rawp == 0xFFFF) {
skb->protocol = htons(ETH_P_802_3);
goto recv;
}
/*
* Real 802.2 LLC
*/
skb->protocol = htons(ETH_P_802_2);
recv:
skb = vlan_check_reorder_header(skb);
if (!skb) {
stats->rx_errors++;
goto err_unlock;
}
netif_rx(skb);
rcu_read_unlock();
return NET_RX_SUCCESS;
err_unlock:
rcu_read_unlock();
err_free:
kfree_skb(skb);
return NET_RX_DROP;
}
static inline unsigned short
vlan_dev_get_egress_qos_mask(struct net_device *dev, struct sk_buff *skb)
{
struct vlan_priority_tci_mapping *mp;
mp = vlan_dev_info(dev)->egress_priority_map[(skb->priority & 0xF)];
while (mp) {
if (mp->priority == skb->priority) {
return mp->vlan_qos; /* This should already be shifted
* to mask correctly with the
* VLAN's TCI */
}
mp = mp->next;
}
return 0;
}
/*
* Create the VLAN header for an arbitrary protocol layer
*
* saddr=NULL means use device source address
* daddr=NULL means leave destination address (eg unresolved arp)
*
* This is called when the SKB is moving down the stack towards the
* physical devices.
*/
static int vlan_dev_hard_header(struct sk_buff *skb, struct net_device *dev,
unsigned short type,
const void *daddr, const void *saddr,
unsigned int len)
{
struct vlan_hdr *vhdr;
unsigned short veth_TCI = 0;
int rc = 0;
int build_vlan_header = 0;
struct net_device *vdev = dev;
pr_debug("%s: skb: %p type: %hx len: %u vlan_id: %hx, daddr: %p\n",
__FUNCTION__, skb, type, len, vlan_dev_info(dev)->vlan_id,
daddr);
/* build vlan header only if re_order_header flag is NOT set. This
* fixes some programs that get confused when they see a VLAN device
* sending a frame that is VLAN encoded (the consensus is that the VLAN
* device should look completely like an Ethernet device when the
* REORDER_HEADER flag is set) The drawback to this is some extra
* header shuffling in the hard_start_xmit. Users can turn off this
* REORDER behaviour with the vconfig tool.
*/
if (!(vlan_dev_info(dev)->flags & VLAN_FLAG_REORDER_HDR))
build_vlan_header = 1;
if (build_vlan_header) {
vhdr = (struct vlan_hdr *) skb_push(skb, VLAN_HLEN);
/* build the four bytes that make this a VLAN header. */
/* Now, construct the second two bytes. This field looks
* something like:
* usr_priority: 3 bits (high bits)
* CFI 1 bit
* VLAN ID 12 bits (low bits)
*
*/
veth_TCI = vlan_dev_info(dev)->vlan_id;
veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
vhdr->h_vlan_TCI = htons(veth_TCI);
/*
* Set the protocol type. For a packet of type ETH_P_802_3 we
* put the length in here instead. It is up to the 802.2
* layer to carry protocol information.
*/
if (type != ETH_P_802_3)
vhdr->h_vlan_encapsulated_proto = htons(type);
else
vhdr->h_vlan_encapsulated_proto = htons(len);
skb->protocol = htons(ETH_P_8021Q);
skb_reset_network_header(skb);
}
/* Before delegating work to the lower layer, enter our MAC-address */
if (saddr == NULL)
saddr = dev->dev_addr;
dev = vlan_dev_info(dev)->real_dev;
/* MPLS can send us skbuffs w/out enough space. This check will grow
* the skb if it doesn't have enough headroom. Not a beautiful solution,
* so I'll tick a counter so that users can know it's happening...
* If they care...
*/
/* NOTE: This may still break if the underlying device is not the final
* device (and thus there are more headers to add...) It should work for
* good-ole-ethernet though.
*/
if (skb_headroom(skb) < dev->hard_header_len) {
struct sk_buff *sk_tmp = skb;
skb = skb_realloc_headroom(sk_tmp, dev->hard_header_len);
kfree_skb(sk_tmp);
if (skb == NULL) {
struct net_device_stats *stats = &vdev->stats;
stats->tx_dropped++;
return -ENOMEM;
}
vlan_dev_info(vdev)->cnt_inc_headroom_on_tx++;
pr_debug("%s: %s: had to grow skb\n", __FUNCTION__, vdev->name);
}
if (build_vlan_header) {
/* Now make the underlying real hard header */
rc = dev_hard_header(skb, dev, ETH_P_8021Q, daddr, saddr,
len + VLAN_HLEN);
if (rc > 0)
rc += VLAN_HLEN;
else if (rc < 0)
rc -= VLAN_HLEN;
} else
/* If here, then we'll just make a normal looking ethernet
* frame, but, the hard_start_xmit method will insert the tag
* (it has to be able to do this for bridged and other skbs
* that don't come down the protocol stack in an orderly manner.
*/
rc = dev_hard_header(skb, dev, type, daddr, saddr, len);
return rc;
}
static int vlan_dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct net_device_stats *stats = &dev->stats;
struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
/* Handle non-VLAN frames if they are sent to us, for example by DHCP.
*
* NOTE: THIS ASSUMES DIX ETHERNET, SPECIFICALLY NOT SUPPORTING
* OTHER THINGS LIKE FDDI/TokenRing/802.3 SNAPs...
*/
if (veth->h_vlan_proto != htons(ETH_P_8021Q) ||
vlan_dev_info(dev)->flags & VLAN_FLAG_REORDER_HDR) {
int orig_headroom = skb_headroom(skb);
unsigned short veth_TCI;
/* This is not a VLAN frame...but we can fix that! */
vlan_dev_info(dev)->cnt_encap_on_xmit++;
pr_debug("%s: proto to encap: 0x%hx\n",
__FUNCTION__, htons(veth->h_vlan_proto));
/* Construct the second two bytes. This field looks something
* like:
* usr_priority: 3 bits (high bits)
* CFI 1 bit
* VLAN ID 12 bits (low bits)
*/
veth_TCI = vlan_dev_info(dev)->vlan_id;
veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
skb = __vlan_put_tag(skb, veth_TCI);
if (!skb) {
stats->tx_dropped++;
return 0;
}
if (orig_headroom < VLAN_HLEN)
vlan_dev_info(dev)->cnt_inc_headroom_on_tx++;
}
pr_debug("%s: about to send skb: %p to dev: %s\n",
__FUNCTION__, skb, skb->dev->name);
pr_debug(" " MAC_FMT " " MAC_FMT " %4hx %4hx %4hx\n",
veth->h_dest[0], veth->h_dest[1], veth->h_dest[2],
veth->h_dest[3], veth->h_dest[4], veth->h_dest[5],
veth->h_source[0], veth->h_source[1], veth->h_source[2],
veth->h_source[3], veth->h_source[4], veth->h_source[5],
veth->h_vlan_proto, veth->h_vlan_TCI,
veth->h_vlan_encapsulated_proto);
stats->tx_packets++; /* for statics only */
stats->tx_bytes += skb->len;
skb->dev = vlan_dev_info(dev)->real_dev;
dev_queue_xmit(skb);
return 0;
}
static int vlan_dev_hwaccel_hard_start_xmit(struct sk_buff *skb,
struct net_device *dev)
{
struct net_device_stats *stats = &dev->stats;
unsigned short veth_TCI;
/* Construct the second two bytes. This field looks something
* like:
* usr_priority: 3 bits (high bits)
* CFI 1 bit
* VLAN ID 12 bits (low bits)
*/
veth_TCI = vlan_dev_info(dev)->vlan_id;
veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
skb = __vlan_hwaccel_put_tag(skb, veth_TCI);
stats->tx_packets++;
stats->tx_bytes += skb->len;
skb->dev = vlan_dev_info(dev)->real_dev;
dev_queue_xmit(skb);
return 0;
}
static int vlan_dev_change_mtu(struct net_device *dev, int new_mtu)
{
/* TODO: gotta make sure the underlying layer can handle it,
* maybe an IFF_VLAN_CAPABLE flag for devices?
*/
if (vlan_dev_info(dev)->real_dev->mtu < new_mtu)
return -ERANGE;
dev->mtu = new_mtu;
return 0;
}
void vlan_dev_set_ingress_priority(const struct net_device *dev,
u32 skb_prio, short vlan_prio)
{
struct vlan_dev_info *vlan = vlan_dev_info(dev);
if (vlan->ingress_priority_map[vlan_prio & 0x7] && !skb_prio)
vlan->nr_ingress_mappings--;
else if (!vlan->ingress_priority_map[vlan_prio & 0x7] && skb_prio)
vlan->nr_ingress_mappings++;
vlan->ingress_priority_map[vlan_prio & 0x7] = skb_prio;
}
int vlan_dev_set_egress_priority(const struct net_device *dev,
u32 skb_prio, short vlan_prio)
{
struct vlan_dev_info *vlan = vlan_dev_info(dev);
struct vlan_priority_tci_mapping *mp = NULL;
struct vlan_priority_tci_mapping *np;
u32 vlan_qos = (vlan_prio << 13) & 0xE000;
/* See if a priority mapping exists.. */
mp = vlan->egress_priority_map[skb_prio & 0xF];
while (mp) {
if (mp->priority == skb_prio) {
if (mp->vlan_qos && !vlan_qos)
vlan->nr_egress_mappings--;
else if (!mp->vlan_qos && vlan_qos)
vlan->nr_egress_mappings++;
mp->vlan_qos = vlan_qos;
return 0;
}
mp = mp->next;
}
/* Create a new mapping then. */
mp = vlan->egress_priority_map[skb_prio & 0xF];
np = kmalloc(sizeof(struct vlan_priority_tci_mapping), GFP_KERNEL);
if (!np)
return -ENOBUFS;
np->next = mp;
np->priority = skb_prio;
np->vlan_qos = vlan_qos;
vlan->egress_priority_map[skb_prio & 0xF] = np;
if (vlan_qos)
vlan->nr_egress_mappings++;
return 0;
}
/* Flags are defined in the vlan_flags enum in include/linux/if_vlan.h file. */
int vlan_dev_set_vlan_flag(const struct net_device *dev,
u32 flag, short flag_val)
{
/* verify flag is supported */
if (flag == VLAN_FLAG_REORDER_HDR) {
if (flag_val)
vlan_dev_info(dev)->flags |= VLAN_FLAG_REORDER_HDR;
else
vlan_dev_info(dev)->flags &= ~VLAN_FLAG_REORDER_HDR;
return 0;
}
return -EINVAL;
}
void vlan_dev_get_realdev_name(const struct net_device *dev, char *result)
{
strncpy(result, vlan_dev_info(dev)->real_dev->name, 23);
}
void vlan_dev_get_vid(const struct net_device *dev, unsigned short *result)
{
*result = vlan_dev_info(dev)->vlan_id;
}
static int vlan_dev_open(struct net_device *dev)
{
struct vlan_dev_info *vlan = vlan_dev_info(dev);
struct net_device *real_dev = vlan->real_dev;
int err;
if (!(real_dev->flags & IFF_UP))
return -ENETDOWN;
if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr)) {
err = dev_unicast_add(real_dev, dev->dev_addr, ETH_ALEN);
if (err < 0)
return err;
}
memcpy(vlan->real_dev_addr, real_dev->dev_addr, ETH_ALEN);
if (dev->flags & IFF_ALLMULTI)
dev_set_allmulti(real_dev, 1);
if (dev->flags & IFF_PROMISC)
dev_set_promiscuity(real_dev, 1);
return 0;
}
static int vlan_dev_stop(struct net_device *dev)
{
struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
dev_mc_unsync(real_dev, dev);
if (dev->flags & IFF_ALLMULTI)
dev_set_allmulti(real_dev, -1);
if (dev->flags & IFF_PROMISC)
dev_set_promiscuity(real_dev, -1);
if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr))
dev_unicast_delete(real_dev, dev->dev_addr, dev->addr_len);
return 0;
}
static int vlan_dev_set_mac_address(struct net_device *dev, void *p)
{
struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
struct sockaddr *addr = p;
int err;
if (!is_valid_ether_addr(addr->sa_data))
return -EADDRNOTAVAIL;
if (!(dev->flags & IFF_UP))
goto out;
if (compare_ether_addr(addr->sa_data, real_dev->dev_addr)) {
err = dev_unicast_add(real_dev, addr->sa_data, ETH_ALEN);
if (err < 0)
return err;
}
if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr))
dev_unicast_delete(real_dev, dev->dev_addr, ETH_ALEN);
out:
memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
return 0;
}
static int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
struct ifreq ifrr;
int err = -EOPNOTSUPP;
strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
ifrr.ifr_ifru = ifr->ifr_ifru;
switch (cmd) {
case SIOCGMIIPHY:
case SIOCGMIIREG:
case SIOCSMIIREG:
if (real_dev->do_ioctl && netif_device_present(real_dev))
err = real_dev->do_ioctl(real_dev, &ifrr, cmd);
break;
}
if (!err)
ifr->ifr_ifru = ifrr.ifr_ifru;
return err;
}
static void vlan_dev_change_rx_flags(struct net_device *dev, int change)
{
struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
if (change & IFF_ALLMULTI)
dev_set_allmulti(real_dev, dev->flags & IFF_ALLMULTI ? 1 : -1);
if (change & IFF_PROMISC)
dev_set_promiscuity(real_dev, dev->flags & IFF_PROMISC ? 1 : -1);
}
static void vlan_dev_set_multicast_list(struct net_device *vlan_dev)
{
dev_mc_sync(vlan_dev_info(vlan_dev)->real_dev, vlan_dev);
}
/*
* vlan network devices have devices nesting below it, and are a special
* "super class" of normal network devices; split their locks off into a
* separate class since they always nest.
*/
static struct lock_class_key vlan_netdev_xmit_lock_key;
static const struct header_ops vlan_header_ops = {
.create = vlan_dev_hard_header,
.rebuild = vlan_dev_rebuild_header,
.parse = eth_header_parse,
};
static int vlan_dev_init(struct net_device *dev)
{
struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
int subclass = 0;
/* IFF_BROADCAST|IFF_MULTICAST; ??? */
dev->flags = real_dev->flags & ~IFF_UP;
dev->iflink = real_dev->ifindex;
dev->state = (real_dev->state & ((1<<__LINK_STATE_NOCARRIER) |
(1<<__LINK_STATE_DORMANT))) |
(1<<__LINK_STATE_PRESENT);
/* ipv6 shared card related stuff */
dev->dev_id = real_dev->dev_id;
if (is_zero_ether_addr(dev->dev_addr))
memcpy(dev->dev_addr, real_dev->dev_addr, dev->addr_len);
if (is_zero_ether_addr(dev->broadcast))
memcpy(dev->broadcast, real_dev->broadcast, dev->addr_len);
if (real_dev->features & NETIF_F_HW_VLAN_TX) {
dev->header_ops = real_dev->header_ops;
dev->hard_header_len = real_dev->hard_header_len;
dev->hard_start_xmit = vlan_dev_hwaccel_hard_start_xmit;
} else {
dev->header_ops = &vlan_header_ops;
dev->hard_header_len = real_dev->hard_header_len + VLAN_HLEN;
dev->hard_start_xmit = vlan_dev_hard_start_xmit;
}
if (real_dev->priv_flags & IFF_802_1Q_VLAN)
subclass = 1;
lockdep_set_class_and_subclass(&dev->_xmit_lock,
&vlan_netdev_xmit_lock_key, subclass);
return 0;
}
void vlan_setup(struct net_device *dev)
{
ether_setup(dev);
dev->priv_flags |= IFF_802_1Q_VLAN;
dev->tx_queue_len = 0;
dev->change_mtu = vlan_dev_change_mtu;
dev->init = vlan_dev_init;
dev->open = vlan_dev_open;
dev->stop = vlan_dev_stop;
dev->set_mac_address = vlan_dev_set_mac_address;
dev->set_multicast_list = vlan_dev_set_multicast_list;
dev->change_rx_flags = vlan_dev_change_rx_flags;
dev->do_ioctl = vlan_dev_ioctl;
dev->destructor = free_netdev;
memset(dev->broadcast, 0, ETH_ALEN);
}
