net/tipc/eth_media.c - maze/linux - Git at Google

 /*
  * net/tipc/eth_media.c: Ethernet bearer support for TIPC
  *
  * Copyright (c) 2001-2007, Ericsson AB
  * Copyright (c) 2005-2007, Wind River Systems
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. Neither the names of the copyright holders nor the names of its
  *    contributors may be used to endorse or promote products derived from
  *    this software without specific prior written permission.
  *
  * Alternatively, this software may be distributed under the terms of the
  * GNU General Public License ("GPL") version 2 as published by the Free
  * Software Foundation.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  */

 #include <net/tipc/tipc.h>
 #include <net/tipc/tipc_bearer.h>
 #include <net/tipc/tipc_msg.h>
 #include <linux/netdevice.h>
 #include <net/net_namespace.h>

 #define MAX_ETH_BEARERS		2
 #define ETH_LINK_PRIORITY	TIPC_DEF_LINK_PRI
 #define ETH_LINK_TOLERANCE	TIPC_DEF_LINK_TOL
 #define ETH_LINK_WINDOW		TIPC_DEF_LINK_WIN

 /**
  * struct eth_bearer - Ethernet bearer data structure
  * @bearer: ptr to associated "generic" bearer structure
  * @dev: ptr to associated Ethernet network device
  * @tipc_packet_type: used in binding TIPC to Ethernet driver
  */

 struct eth_bearer {
 	struct tipc_bearer *bearer;
 	struct net_device *dev;
 	struct packet_type tipc_packet_type;
 };

 static struct eth_bearer eth_bearers[MAX_ETH_BEARERS];
 static int eth_started = 0;
 static struct notifier_block notifier;

 /**
  * send_msg - send a TIPC message out over an Ethernet interface
  */

 static int send_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr,
 		    struct tipc_media_addr *dest)
 {
 	struct sk_buff *clone;
 	struct net_device *dev;

 	clone = skb_clone(buf, GFP_ATOMIC);
 	if (clone) {
 		skb_reset_network_header(clone);
 		dev = ((struct eth_bearer *)(tb_ptr->usr_handle))->dev;
 		clone->dev = dev;
 		dev->hard_header(clone, dev, ETH_P_TIPC,
 				 &dest->dev_addr.eth_addr,
 				 dev->dev_addr, clone->len);
 		dev_queue_xmit(clone);
 	}
 	return TIPC_OK;
 }

 /**
  * recv_msg - handle incoming TIPC message from an Ethernet interface
  *
  * Accept only packets explicitly sent to this node, or broadcast packets;
  * ignores packets sent using Ethernet multicast, and traffic sent to other
  * nodes (which can happen if interface is running in promiscuous mode).
  * Routine truncates any Ethernet padding/CRC appended to the message,
  * and ensures message size matches actual length
  */

 static int recv_msg(struct sk_buff *buf, struct net_device *dev,
 		    struct packet_type *pt, struct net_device *orig_dev)
 {
 	struct eth_bearer *eb_ptr = (struct eth_bearer *)pt->af_packet_priv;
 	u32 size;

 	if (dev->nd_net != &init_net) {
 		kfree_skb(buf);
 		return 0;
 	}

 	if (likely(eb_ptr->bearer)) {
 		if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
 			size = msg_size((struct tipc_msg *)buf->data);
 			skb_trim(buf, size);
 			if (likely(buf->len == size)) {
 				buf->next = NULL;
 				tipc_recv_msg(buf, eb_ptr->bearer);
 				return TIPC_OK;
 			}
 		}
 	}
 	kfree_skb(buf);
 	return TIPC_OK;
 }

 /**
  * enable_bearer - attach TIPC bearer to an Ethernet interface
  */

 static int enable_bearer(struct tipc_bearer *tb_ptr)
 {
 	struct net_device *dev = NULL;
 	struct net_device *pdev = NULL;
 	struct eth_bearer *eb_ptr = &eth_bearers[0];
 	struct eth_bearer *stop = &eth_bearers[MAX_ETH_BEARERS];
 	char *driver_name = strchr((const char *)tb_ptr->name, ':') + 1;

 	/* Find device with specified name */

 	for_each_netdev(&init_net, pdev){
 		if (!strncmp(pdev->name, driver_name, IFNAMSIZ)) {
 			dev = pdev;
 			break;
 		}
 	}
 	if (!dev)
 		return -ENODEV;

 	/* Find Ethernet bearer for device (or create one) */

 	for (;(eb_ptr != stop) && eb_ptr->dev && (eb_ptr->dev != dev); eb_ptr++);
 	if (eb_ptr == stop)
 		return -EDQUOT;
 	if (!eb_ptr->dev) {
 		eb_ptr->dev = dev;
 		eb_ptr->tipc_packet_type.type = htons(ETH_P_TIPC);
 		eb_ptr->tipc_packet_type.dev = dev;
 		eb_ptr->tipc_packet_type.func = recv_msg;
 		eb_ptr->tipc_packet_type.af_packet_priv = eb_ptr;
 		INIT_LIST_HEAD(&(eb_ptr->tipc_packet_type.list));
 		dev_hold(dev);
 		dev_add_pack(&eb_ptr->tipc_packet_type);
 	}

 	/* Associate TIPC bearer with Ethernet bearer */

 	eb_ptr->bearer = tb_ptr;
 	tb_ptr->usr_handle = (void *)eb_ptr;
 	tb_ptr->mtu = dev->mtu;
 	tb_ptr->blocked = 0;
 	tb_ptr->addr.type = htonl(TIPC_MEDIA_TYPE_ETH);
 	memcpy(&tb_ptr->addr.dev_addr, &dev->dev_addr, ETH_ALEN);
 	return 0;
 }

 /**
  * disable_bearer - detach TIPC bearer from an Ethernet interface
  *
  * We really should do dev_remove_pack() here, but this function can not be
  * called at tasklet level. => Use eth_bearer->bearer as a flag to throw away
  * incoming buffers, & postpone dev_remove_pack() to eth_media_stop() on exit.
  */

 static void disable_bearer(struct tipc_bearer *tb_ptr)
 {
 	((struct eth_bearer *)tb_ptr->usr_handle)->bearer = NULL;
 }

 /**
  * recv_notification - handle device updates from OS
  *
  * Change the state of the Ethernet bearer (if any) associated with the
  * specified device.
  */

 static int recv_notification(struct notifier_block *nb, unsigned long evt,
 			     void *dv)
 {
 	struct net_device *dev = (struct net_device *)dv;
 	struct eth_bearer *eb_ptr = &eth_bearers[0];
 	struct eth_bearer *stop = &eth_bearers[MAX_ETH_BEARERS];

 	if (dev->nd_net != &init_net)
 		return NOTIFY_DONE;

 	while ((eb_ptr->dev != dev)) {
 		if (++eb_ptr == stop)
 			return NOTIFY_DONE;	/* couldn't find device */
 	}
 	if (!eb_ptr->bearer)
 		return NOTIFY_DONE;		/* bearer had been disabled */

 	eb_ptr->bearer->mtu = dev->mtu;

 	switch (evt) {
 	case NETDEV_CHANGE:
 		if (netif_carrier_ok(dev))
 			tipc_continue(eb_ptr->bearer);
 		else
 			tipc_block_bearer(eb_ptr->bearer->name);
 		break;
 	case NETDEV_UP:
 		tipc_continue(eb_ptr->bearer);
 		break;
 	case NETDEV_DOWN:
 		tipc_block_bearer(eb_ptr->bearer->name);
 		break;
 	case NETDEV_CHANGEMTU:
 	case NETDEV_CHANGEADDR:
 		tipc_block_bearer(eb_ptr->bearer->name);
 		tipc_continue(eb_ptr->bearer);
 		break;
 	case NETDEV_UNREGISTER:
 	case NETDEV_CHANGENAME:
 		tipc_disable_bearer(eb_ptr->bearer->name);
 		break;
 	}
 	return NOTIFY_OK;
 }

 /**
  * eth_addr2str - convert Ethernet address to string
  */

 static char *eth_addr2str(struct tipc_media_addr *a, char *str_buf, int str_size)
 {
 	unchar *addr = (unchar *)&a->dev_addr;

 	if (str_size < 18)
 		*str_buf = '\0';
 	else
 		sprintf(str_buf, "%02x:%02x:%02x:%02x:%02x:%02x",
 			addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
 	return str_buf;
 }

 /**
  * tipc_eth_media_start - activate Ethernet bearer support
  *
  * Register Ethernet media type with TIPC bearer code.  Also register
  * with OS for notifications about device state changes.
  */

 int tipc_eth_media_start(void)
 {
 	struct tipc_media_addr bcast_addr;
 	int res;

 	if (eth_started)
 		return -EINVAL;

 	bcast_addr.type = htonl(TIPC_MEDIA_TYPE_ETH);
 	memset(&bcast_addr.dev_addr, 0xff, ETH_ALEN);

 	memset(eth_bearers, 0, sizeof(eth_bearers));

 	res = tipc_register_media(TIPC_MEDIA_TYPE_ETH, "eth",
 				  enable_bearer, disable_bearer, send_msg,
 				  eth_addr2str, &bcast_addr, ETH_LINK_PRIORITY,
 				  ETH_LINK_TOLERANCE, ETH_LINK_WINDOW);
 	if (res)
 		return res;

 	notifier.notifier_call = &recv_notification;
 	notifier.priority = 0;
 	res = register_netdevice_notifier(&notifier);
 	if (!res)
 		eth_started = 1;
 	return res;
 }

 /**
  * tipc_eth_media_stop - deactivate Ethernet bearer support
  */

 void tipc_eth_media_stop(void)
 {
 	int i;

 	if (!eth_started)
 		return;

 	unregister_netdevice_notifier(&notifier);
 	for (i = 0; i < MAX_ETH_BEARERS ; i++) {
 		if (eth_bearers[i].bearer) {
 			eth_bearers[i].bearer->blocked = 1;
 			eth_bearers[i].bearer = NULL;
 		}
 		if (eth_bearers[i].dev) {
 			dev_remove_pack(&eth_bearers[i].tipc_packet_type);
 			dev_put(eth_bearers[i].dev);
 		}
 	}
 	memset(&eth_bearers, 0, sizeof(eth_bearers));
 	eth_started = 0;
 }
	/*
	* net/tipc/eth_media.c: Ethernet bearer support for TIPC
	*
	* Copyright (c) 2001-2007, Ericsson AB
	* Copyright (c) 2005-2007, Wind River Systems
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are met:
	*
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. Neither the names of the copyright holders nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* Alternatively, this software may be distributed under the terms of the
	* GNU General Public License ("GPL") version 2 as published by the Free
	* Software Foundation.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	* POSSIBILITY OF SUCH DAMAGE.
	*/

	#include <net/tipc/tipc.h>
	#include <net/tipc/tipc_bearer.h>
	#include <net/tipc/tipc_msg.h>
	#include <linux/netdevice.h>
	#include <net/net_namespace.h>

	#define MAX_ETH_BEARERS 2
	#define ETH_LINK_PRIORITY TIPC_DEF_LINK_PRI
	#define ETH_LINK_TOLERANCE TIPC_DEF_LINK_TOL
	#define ETH_LINK_WINDOW TIPC_DEF_LINK_WIN

	/**
	* struct eth_bearer - Ethernet bearer data structure
	* @bearer: ptr to associated "generic" bearer structure
	* @dev: ptr to associated Ethernet network device
	* @tipc_packet_type: used in binding TIPC to Ethernet driver
	*/

	struct eth_bearer {
	struct tipc_bearer *bearer;
	struct net_device *dev;
	struct packet_type tipc_packet_type;
	};

	static struct eth_bearer eth_bearers[MAX_ETH_BEARERS];
	static int eth_started = 0;
	static struct notifier_block notifier;

	/**
	* send_msg - send a TIPC message out over an Ethernet interface
	*/

	static int send_msg(struct sk_buff buf, struct tipc_bearer tb_ptr,
	struct tipc_media_addr *dest)
	{
	struct sk_buff *clone;
	struct net_device *dev;

	clone = skb_clone(buf, GFP_ATOMIC);
	if (clone) {
	skb_reset_network_header(clone);
	dev = ((struct eth_bearer *)(tb_ptr->usr_handle))->dev;
	clone->dev = dev;
	dev->hard_header(clone, dev, ETH_P_TIPC,
	&dest->dev_addr.eth_addr,
	dev->dev_addr, clone->len);
	dev_queue_xmit(clone);
	}
	return TIPC_OK;
	}

	/**
	* recv_msg - handle incoming TIPC message from an Ethernet interface
	*
	* Accept only packets explicitly sent to this node, or broadcast packets;
	* ignores packets sent using Ethernet multicast, and traffic sent to other
	* nodes (which can happen if interface is running in promiscuous mode).
	* Routine truncates any Ethernet padding/CRC appended to the message,
	* and ensures message size matches actual length
	*/

	static int recv_msg(struct sk_buff buf, struct net_device dev,
	struct packet_type pt, struct net_device orig_dev)
	{
	struct eth_bearer eb_ptr = (struct eth_bearer )pt->af_packet_priv;
	u32 size;

	if (dev->nd_net != &init_net) {
	kfree_skb(buf);
	return 0;
	}

	if (likely(eb_ptr->bearer)) {
	if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
	size = msg_size((struct tipc_msg *)buf->data);
	skb_trim(buf, size);
	if (likely(buf->len == size)) {
	buf->next = NULL;
	tipc_recv_msg(buf, eb_ptr->bearer);
	return TIPC_OK;
	}
	}
	}
	kfree_skb(buf);
	return TIPC_OK;
	}

	/**
	* enable_bearer - attach TIPC bearer to an Ethernet interface
	*/

	static int enable_bearer(struct tipc_bearer *tb_ptr)
	{
	struct net_device *dev = NULL;
	struct net_device *pdev = NULL;
	struct eth_bearer *eb_ptr = &eth_bearers[0];
	struct eth_bearer *stop = &eth_bearers[MAX_ETH_BEARERS];
	char driver_name = strchr((const char )tb_ptr->name, ':') + 1;

	/* Find device with specified name */

	for_each_netdev(&init_net, pdev){
	if (!strncmp(pdev->name, driver_name, IFNAMSIZ)) {
	dev = pdev;
	break;
	}
	}
	if (!dev)
	return -ENODEV;

	/* Find Ethernet bearer for device (or create one) */

	for (;(eb_ptr != stop) && eb_ptr->dev && (eb_ptr->dev != dev); eb_ptr++);
	if (eb_ptr == stop)
	return -EDQUOT;
	if (!eb_ptr->dev) {
	eb_ptr->dev = dev;
	eb_ptr->tipc_packet_type.type = htons(ETH_P_TIPC);
	eb_ptr->tipc_packet_type.dev = dev;
	eb_ptr->tipc_packet_type.func = recv_msg;
	eb_ptr->tipc_packet_type.af_packet_priv = eb_ptr;
	INIT_LIST_HEAD(&(eb_ptr->tipc_packet_type.list));
	dev_hold(dev);
	dev_add_pack(&eb_ptr->tipc_packet_type);
	}

	/* Associate TIPC bearer with Ethernet bearer */

	eb_ptr->bearer = tb_ptr;
	tb_ptr->usr_handle = (void *)eb_ptr;
	tb_ptr->mtu = dev->mtu;
	tb_ptr->blocked = 0;
	tb_ptr->addr.type = htonl(TIPC_MEDIA_TYPE_ETH);
	memcpy(&tb_ptr->addr.dev_addr, &dev->dev_addr, ETH_ALEN);
	return 0;
	}

	/**
	* disable_bearer - detach TIPC bearer from an Ethernet interface
	*
	* We really should do dev_remove_pack() here, but this function can not be
	* called at tasklet level. => Use eth_bearer->bearer as a flag to throw away
	* incoming buffers, & postpone dev_remove_pack() to eth_media_stop() on exit.
	*/

	static void disable_bearer(struct tipc_bearer *tb_ptr)
	{
	((struct eth_bearer *)tb_ptr->usr_handle)->bearer = NULL;
	}

	/**
	* recv_notification - handle device updates from OS
	*
	* Change the state of the Ethernet bearer (if any) associated with the
	* specified device.
	*/

	static int recv_notification(struct notifier_block *nb, unsigned long evt,
	void *dv)
	{
	struct net_device dev = (struct net_device )dv;
	struct eth_bearer *eb_ptr = &eth_bearers[0];
	struct eth_bearer *stop = &eth_bearers[MAX_ETH_BEARERS];

	if (dev->nd_net != &init_net)
	return NOTIFY_DONE;

	while ((eb_ptr->dev != dev)) {
	if (++eb_ptr == stop)
	return NOTIFY_DONE; /* couldn't find device */
	}
	if (!eb_ptr->bearer)
	return NOTIFY_DONE; /* bearer had been disabled */

	eb_ptr->bearer->mtu = dev->mtu;

	switch (evt) {
	case NETDEV_CHANGE:
	if (netif_carrier_ok(dev))
	tipc_continue(eb_ptr->bearer);
	else
	tipc_block_bearer(eb_ptr->bearer->name);
	break;
	case NETDEV_UP:
	tipc_continue(eb_ptr->bearer);
	break;
	case NETDEV_DOWN:
	tipc_block_bearer(eb_ptr->bearer->name);
	break;
	case NETDEV_CHANGEMTU:
	case NETDEV_CHANGEADDR:
	tipc_block_bearer(eb_ptr->bearer->name);
	tipc_continue(eb_ptr->bearer);
	break;
	case NETDEV_UNREGISTER:
	case NETDEV_CHANGENAME:
	tipc_disable_bearer(eb_ptr->bearer->name);
	break;
	}
	return NOTIFY_OK;
	}

	/**
	* eth_addr2str - convert Ethernet address to string
	*/

	static char eth_addr2str(struct tipc_media_addr a, char *str_buf, int str_size)
	{
	unchar addr = (unchar )&a->dev_addr;

	if (str_size < 18)
	*str_buf = '\0';
	else
	sprintf(str_buf, "%02x:%02x:%02x:%02x:%02x:%02x",
	addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
	return str_buf;
	}

	/**
	* tipc_eth_media_start - activate Ethernet bearer support
	*
	* Register Ethernet media type with TIPC bearer code. Also register
	* with OS for notifications about device state changes.
	*/

	int tipc_eth_media_start(void)
	{
	struct tipc_media_addr bcast_addr;
	int res;

	if (eth_started)
	return -EINVAL;

	bcast_addr.type = htonl(TIPC_MEDIA_TYPE_ETH);
	memset(&bcast_addr.dev_addr, 0xff, ETH_ALEN);

	memset(eth_bearers, 0, sizeof(eth_bearers));

	res = tipc_register_media(TIPC_MEDIA_TYPE_ETH, "eth",
	enable_bearer, disable_bearer, send_msg,
	eth_addr2str, &bcast_addr, ETH_LINK_PRIORITY,
	ETH_LINK_TOLERANCE, ETH_LINK_WINDOW);
	if (res)
	return res;

	notifier.notifier_call = &recv_notification;
	notifier.priority = 0;
	res = register_netdevice_notifier(&notifier);
	if (!res)
	eth_started = 1;
	return res;
	}

	/**
	* tipc_eth_media_stop - deactivate Ethernet bearer support
	*/

	void tipc_eth_media_stop(void)
	{
	int i;

	if (!eth_started)
	return;

	unregister_netdevice_notifier(&notifier);
	for (i = 0; i < MAX_ETH_BEARERS ; i++) {
	if (eth_bearers[i].bearer) {
	eth_bearers[i].bearer->blocked = 1;
	eth_bearers[i].bearer = NULL;
	}
	if (eth_bearers[i].dev) {
	dev_remove_pack(&eth_bearers[i].tipc_packet_type);
	dev_put(eth_bearers[i].dev);
	}
	}
	memset(&eth_bearers, 0, sizeof(eth_bearers));
	eth_started = 0;
	}