/*
* Copyright (C) 2010 Michael Brown <mbrown@fensystems.co.uk>.
*
* 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 any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* You can also choose to distribute this program under the terms of
* the Unmodified Binary Distribution Licence (as given in the file
* COPYING.UBDL), provided that you have satisfied its requirements.
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
#include <stdint.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <byteswap.h>
#include <ipxe/features.h>
#include <ipxe/if_ether.h>
#include <ipxe/ethernet.h>
#include <ipxe/netdevice.h>
#include <ipxe/iobuf.h>
#include <ipxe/vlan.h>
/** @file
*
* Virtual LANs
*
*/
FEATURE ( FEATURE_PROTOCOL, "VLAN", DHCP_EB_FEATURE_VLAN, 1 );
struct net_protocol vlan_protocol __net_protocol;
/** VLAN device private data */
struct vlan_device {
/** Trunk network device */
struct net_device *trunk;
/** VLAN tag */
unsigned int tag;
/** Default priority */
unsigned int priority;
};
/**
* Open VLAN device
*
* @v netdev Network device
* @ret rc Return status code
*/
static int vlan_open ( struct net_device *netdev ) {
struct vlan_device *vlan = netdev->priv;
return netdev_open ( vlan->trunk );
}
/**
* Close VLAN device
*
* @v netdev Network device
*/
static void vlan_close ( struct net_device *netdev ) {
struct vlan_device *vlan = netdev->priv;
netdev_close ( vlan->trunk );
}
/**
* Transmit packet on VLAN device
*
* @v netdev Network device
* @v iobuf I/O buffer
* @ret rc Return status code
*/
static int vlan_transmit ( struct net_device *netdev,
struct io_buffer *iobuf ) {
struct vlan_device *vlan = netdev->priv;
struct net_device *trunk = vlan->trunk;
struct ll_protocol *ll_protocol;
struct vlan_header *vlanhdr;
uint8_t ll_dest_copy[ETH_ALEN];
uint8_t ll_source_copy[ETH_ALEN];
const void *ll_dest;
const void *ll_source;
uint16_t net_proto;
unsigned int flags;
int rc;
/* Strip link-layer header and preserve link-layer header fields */
ll_protocol = netdev->ll_protocol;
if ( ( rc = ll_protocol->pull ( netdev, iobuf, &ll_dest, &ll_source,
&net_proto, &flags ) ) != 0 ) {
DBGC ( netdev, "VLAN %s could not parse link-layer header: "
"%s\n", netdev->name, strerror ( rc ) );
return rc;
}
memcpy ( ll_dest_copy, ll_dest, ETH_ALEN );
memcpy ( ll_source_copy, ll_source, ETH_ALEN );
/* Construct VLAN header */
vlanhdr = iob_push ( iobuf, sizeof ( *vlanhdr ) );
vlanhdr->tci = htons ( VLAN_TCI ( vlan->tag, vlan->priority ) );
vlanhdr->net_proto = net_proto;
/* Reclaim I/O buffer from VLAN device's TX queue */
list_del ( &iobuf->list );
/* Transmit packet on trunk device */
if ( ( rc = net_tx ( iob_disown ( iobuf ), trunk, &vlan_protocol,
ll_dest_copy, ll_source_copy ) ) != 0 ) {
DBGC ( netdev, "VLAN %s could not transmit: %s\n",
netdev->name, strerror ( rc ) );
/* Cannot return an error status, since that would
* cause the I/O buffer to be double-freed.
*/
return 0;
}
return 0;
}
/**
* Poll VLAN device
*
* @v netdev Network device
*/
static void vlan_poll ( struct net_device *netdev ) {
struct vlan_device *vlan = netdev->priv;
/* Poll trunk device */
netdev_poll ( vlan->trunk );
}
/**
* Enable/disable interrupts on VLAN device
*
* @v netdev Network device
* @v enable Interrupts should be enabled
*/
static void vlan_irq ( struct net_device *netdev, int enable ) {
struct vlan_device *vlan = netdev->priv;
/* Enable/disable interrupts on trunk device. This is not at
* all robust, but there is no sensible course of action
* available.
*/
netdev_irq ( vlan->trunk, enable );
}
/** VLAN device operations */
static struct net_device_operations vlan_operations = {
.open = vlan_open,
.close = vlan_close,
.transmit = vlan_transmit,
.poll = vlan_poll,
.irq = vlan_irq,
};
/**
* Synchronise VLAN device
*
* @v netdev Network device
*/
static void vlan_sync ( struct net_device *netdev ) {
struct vlan_device *vlan = netdev->priv;
struct net_device *trunk = vlan->trunk;
/* Synchronise link status */
if ( netdev->link_rc != trunk->link_rc )
netdev_link_err ( netdev, trunk->link_rc );
/* Synchronise open/closed status */
if ( netdev_is_open ( trunk ) ) {
if ( ! netdev_is_open ( netdev ) )
netdev_open ( netdev );
} else {
if ( netdev_is_open ( netdev ) )
netdev_close ( netdev );
}
}
/**
* Identify VLAN device
*
* @v trunk Trunk network device
* @v tag VLAN tag
* @ret netdev VLAN device, if any
*/
struct net_device * vlan_find ( struct net_device *trunk, unsigned int tag ) {
struct net_device *netdev;
struct vlan_device *vlan;
for_each_netdev ( netdev ) {
if ( netdev->op != &vlan_operations )
continue;
vlan = netdev->priv;
if ( ( vlan->trunk == trunk ) && ( vlan->tag == tag ) )
return netdev;
}
return NULL;
}
/**
* Process incoming VLAN packet
*
* @v iobuf I/O buffer
* @v trunk Trunk network device
* @v ll_dest Link-layer destination address
* @v ll_source Link-layer source address
* @v flags Packet flags
* @ret rc Return status code
*/
static int vlan_rx ( struct io_buffer *iobuf, struct net_device *trunk,
const void *ll_dest, const void *ll_source,
unsigned int flags __unused ) {
struct vlan_header *vlanhdr = iobuf->data;
struct net_device *netdev;
struct ll_protocol *ll_protocol;
uint8_t ll_dest_copy[ETH_ALEN];
uint8_t ll_source_copy[ETH_ALEN];
uint16_t tag;
int rc;
/* Sanity check */
if ( iob_len ( iobuf ) < sizeof ( *vlanhdr ) ) {
DBGC ( trunk, "VLAN %s received underlength packet (%zd "
"bytes)\n", trunk->name, iob_len ( iobuf ) );
rc = -EINVAL;
goto err_sanity;
}
/* Identify VLAN device */
tag = VLAN_TAG ( ntohs ( vlanhdr->tci ) );
netdev = vlan_find ( trunk, tag );
if ( ! netdev ) {
DBGC2 ( trunk, "VLAN %s received packet for unknown VLAN "
"%d\n", trunk->name, tag );
rc = -EPIPE;
goto err_no_vlan;
}
/* Strip VLAN header and preserve original link-layer header fields */
iob_pull ( iobuf, sizeof ( *vlanhdr ) );
ll_protocol = trunk->ll_protocol;
memcpy ( ll_dest_copy, ll_dest, ETH_ALEN );
memcpy ( ll_source_copy, ll_source, ETH_ALEN );
/* Reconstruct link-layer header for VLAN device */
ll_protocol = netdev->ll_protocol;
if ( ( rc = ll_protocol->push ( netdev, iobuf, ll_dest_copy,
ll_source_copy,
vlanhdr->net_proto ) ) != 0 ) {
DBGC ( netdev, "VLAN %s could not reconstruct link-layer "
"header: %s\n", netdev->name, strerror ( rc ) );
goto err_ll_push;
}
/* Enqueue packet on VLAN device */
netdev_rx ( netdev, iob_disown ( iobuf ) );
return 0;
err_ll_push:
err_no_vlan:
err_sanity:
free_iob ( iobuf );
return rc;
}
/** VLAN protocol */
struct net_protocol vlan_protocol __net_protocol = {
.name = "VLAN",
.net_proto = htons ( ETH_P_8021Q ),
.rx = vlan_rx,
};
/**
* Get the VLAN tag
*
* @v netdev Network device
* @ret tag VLAN tag, or 0 if device is not a VLAN device
*/
unsigned int vlan_tag ( struct net_device *netdev ) {
struct vlan_device *vlan;
if ( netdev->op == &vlan_operations ) {
vlan = netdev->priv;
return vlan->tag;
} else {
return 0;
}
}
/**
* Check if network device can be used as a VLAN trunk device
*
* @v trunk Trunk network device
* @ret is_ok Trunk network device is usable
*
* VLAN devices will be created as Ethernet devices. (We cannot
* simply clone the link layer of the trunk network device, because
* this link layer may expect the network device structure to contain
* some link-layer-private data.) The trunk network device must
* therefore have a link layer that is in some sense 'compatible' with
* Ethernet; specifically, it must have link-layer addresses that are
* the same length as Ethernet link-layer addresses.
*
* As an additional check, and primarily to assist with the sanity of
* the FCoE code, we refuse to allow nested VLANs.
*/
int vlan_can_be_trunk ( struct net_device *trunk ) {
return ( ( trunk->ll_protocol->ll_addr_len == ETH_ALEN ) &&
( trunk->op != &vlan_operations ) );
}
/**
* Create VLAN device
*
* @v trunk Trunk network device
* @v tag VLAN tag
* @v priority Default VLAN priority
* @ret rc Return status code
*/
int vlan_create ( struct net_device *trunk, unsigned int tag,
unsigned int priority ) {
struct net_device *netdev;
struct vlan_device *vlan;
int rc;
/* If VLAN already exists, just update the priority */
if ( ( netdev = vlan_find ( trunk, tag ) ) != NULL ) {
vlan = netdev->priv;
if ( priority != vlan->priority ) {
DBGC ( netdev, "VLAN %s priority changed from %d to "
"%d\n", netdev->name, vlan->priority, priority );
}
vlan->priority = priority;
return 0;
}
/* Sanity checks */
if ( ! vlan_can_be_trunk ( trunk ) ) {
DBGC ( trunk, "VLAN %s cannot create VLAN on non-trunk "
"device\n", trunk->name );
rc = -ENOTTY;
goto err_sanity;
}
if ( ! VLAN_TAG_IS_VALID ( tag ) ) {
DBGC ( trunk, "VLAN %s cannot create VLAN with invalid tag "
"%d\n", trunk->name, tag );
rc = -EINVAL;
goto err_sanity;
}
if ( ! VLAN_PRIORITY_IS_VALID ( priority ) ) {
DBGC ( trunk, "VLAN %s cannot create VLAN with invalid "
"priority %d\n", trunk->name, priority );
rc = -EINVAL;
goto err_sanity;
}
/* Allocate and initialise structure */
netdev = alloc_etherdev ( sizeof ( *vlan ) );
if ( ! netdev ) {
rc = -ENOMEM;
goto err_alloc_etherdev;
}
netdev_init ( netdev, &vlan_operations );
netdev->dev = trunk->dev;
memcpy ( netdev->hw_addr, trunk->ll_addr, ETH_ALEN );
vlan = netdev->priv;
vlan->trunk = netdev_get ( trunk );
vlan->tag = tag;
vlan->priority = priority;
/* Construct VLAN device name */
snprintf ( netdev->name, sizeof ( netdev->name ), "%s-%d",
trunk->name, vlan->tag );
/* Mark device as not supporting interrupts, if applicable */
if ( ! netdev_irq_supported ( trunk ) )
netdev->state |= NETDEV_IRQ_UNSUPPORTED;
/* Register VLAN device */
if ( ( rc = register_netdev ( netdev ) ) != 0 ) {
DBGC ( netdev, "VLAN %s could not register: %s\n",
netdev->name, strerror ( rc ) );
goto err_register;
}
/* Synchronise with trunk device */
vlan_sync ( netdev );
DBGC ( netdev, "VLAN %s created with tag %d and priority %d\n",
netdev->name, vlan->tag, vlan->priority );
return 0;
unregister_netdev ( netdev );
err_register:
netdev_nullify ( netdev );
netdev_put ( netdev );
netdev_put ( trunk );
err_alloc_etherdev:
err_sanity:
return rc;
}
/**
* Destroy VLAN device
*
* @v netdev Network device
* @ret rc Return status code
*/
int vlan_destroy ( struct net_device *netdev ) {
struct vlan_device *vlan = netdev->priv;
struct net_device *trunk;
/* Sanity check */
if ( netdev->op != &vlan_operations ) {
DBGC ( netdev, "VLAN %s cannot destroy non-VLAN device\n",
netdev->name );
return -ENOTTY;
}
DBGC ( netdev, "VLAN %s destroyed\n", netdev->name );
/* Remove VLAN device */
unregister_netdev ( netdev );
trunk = vlan->trunk;
netdev_nullify ( netdev );
netdev_put ( netdev );
netdev_put ( trunk );
return 0;
}
/**
* Handle trunk network device link state change
*
* @v trunk Trunk network device
*/
static void vlan_notify ( struct net_device *trunk ) {
struct net_device *netdev;
struct vlan_device *vlan;
for_each_netdev ( netdev ) {
if ( netdev->op != &vlan_operations )
continue;
vlan = netdev->priv;
if ( vlan->trunk == trunk )
vlan_sync ( netdev );
}
}
/**
* Destroy first VLAN device for a given trunk
*
* @v trunk Trunk network device
* @ret found A VLAN device was found
*/
static int vlan_remove_first ( struct net_device *trunk ) {
struct net_device *netdev;
struct vlan_device *vlan;
for_each_netdev ( netdev ) {
if ( netdev->op != &vlan_operations )
continue;
vlan = netdev->priv;
if ( vlan->trunk == trunk ) {
vlan_destroy ( netdev );
return 1;
}
}
return 0;
}
/**
* Destroy all VLAN devices for a given trunk
*
* @v trunk Trunk network device
*/
static void vlan_remove ( struct net_device *trunk ) {
/* Remove all VLAN devices attached to this trunk, safe
* against arbitrary net device removal.
*/
while ( vlan_remove_first ( trunk ) ) {}
}
/** VLAN driver */
struct net_driver vlan_driver __net_driver = {
.name = "VLAN",
.notify = vlan_notify,
.remove = vlan_remove,
};
