net/l2tp/l2tp_eth.c - kernel/msm-4.19 - Gitiles

 /*
  * L2TPv3 ethernet pseudowire driver
  *
  * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
  *
  *	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.
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

 #include <linux/module.h>
 #include <linux/skbuff.h>
 #include <linux/socket.h>
 #include <linux/hash.h>
 #include <linux/l2tp.h>
 #include <linux/in.h>
 #include <linux/etherdevice.h>
 #include <linux/spinlock.h>
 #include <net/sock.h>
 #include <net/ip.h>
 #include <net/icmp.h>
 #include <net/udp.h>
 #include <net/inet_common.h>
 #include <net/inet_hashtables.h>
 #include <net/tcp_states.h>
 #include <net/protocol.h>
 #include <net/xfrm.h>
 #include <net/net_namespace.h>
 #include <net/netns/generic.h>

 #include "l2tp_core.h"

 /* Default device name. May be overridden by name specified by user */
 #define L2TP_ETH_DEV_NAME	"l2tpeth%d"

 /* via netdev_priv() */
 struct l2tp_eth {
 	struct net_device	*dev;
 	struct sock		*tunnel_sock;
 	struct l2tp_session	*session;
 	struct list_head	list;
 	atomic_long_t		tx_bytes;
 	atomic_long_t		tx_packets;
 	atomic_long_t		tx_dropped;
 	atomic_long_t		rx_bytes;
 	atomic_long_t		rx_packets;
 	atomic_long_t		rx_errors;
 };

 /* via l2tp_session_priv() */
 struct l2tp_eth_sess {
 	struct net_device	*dev;
 };

 /* per-net private data for this module */
 static unsigned int l2tp_eth_net_id;
 struct l2tp_eth_net {
 	struct list_head l2tp_eth_dev_list;
 	spinlock_t l2tp_eth_lock;
 };

 static inline struct l2tp_eth_net *l2tp_eth_pernet(struct net *net)
 {
 	return net_generic(net, l2tp_eth_net_id);
 }

 static int l2tp_eth_dev_init(struct net_device *dev)
 {
 	struct l2tp_eth *priv = netdev_priv(dev);

 	priv->dev = dev;
 	eth_hw_addr_random(dev);
 	eth_broadcast_addr(dev->broadcast);
 	netdev_lockdep_set_classes(dev);

 	return 0;
 }

 static void l2tp_eth_dev_uninit(struct net_device *dev)
 {
 	struct l2tp_eth *priv = netdev_priv(dev);
 	struct l2tp_eth_net *pn = l2tp_eth_pernet(dev_net(dev));

 	spin_lock(&pn->l2tp_eth_lock);
 	list_del_init(&priv->list);
 	spin_unlock(&pn->l2tp_eth_lock);
 	dev_put(dev);
 }

 static int l2tp_eth_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct l2tp_eth *priv = netdev_priv(dev);
 	struct l2tp_session *session = priv->session;
 	unsigned int len = skb->len;
 	int ret = l2tp_xmit_skb(session, skb, session->hdr_len);

 	if (likely(ret == NET_XMIT_SUCCESS)) {
 		atomic_long_add(len, &priv->tx_bytes);
 		atomic_long_inc(&priv->tx_packets);
 	} else {
 		atomic_long_inc(&priv->tx_dropped);
 	}
 	return NETDEV_TX_OK;
 }

 static void l2tp_eth_get_stats64(struct net_device *dev,
 				 struct rtnl_link_stats64 *stats)
 {
 	struct l2tp_eth *priv = netdev_priv(dev);

 	stats->tx_bytes   = atomic_long_read(&priv->tx_bytes);
 	stats->tx_packets = atomic_long_read(&priv->tx_packets);
 	stats->tx_dropped = atomic_long_read(&priv->tx_dropped);
 	stats->rx_bytes   = atomic_long_read(&priv->rx_bytes);
 	stats->rx_packets = atomic_long_read(&priv->rx_packets);
 	stats->rx_errors  = atomic_long_read(&priv->rx_errors);
 }

 static const struct net_device_ops l2tp_eth_netdev_ops = {
 	.ndo_init		= l2tp_eth_dev_init,
 	.ndo_uninit		= l2tp_eth_dev_uninit,
 	.ndo_start_xmit		= l2tp_eth_dev_xmit,
 	.ndo_get_stats64	= l2tp_eth_get_stats64,
 	.ndo_set_mac_address	= eth_mac_addr,
 };

 static void l2tp_eth_dev_setup(struct net_device *dev)
 {
 	ether_setup(dev);
 	dev->priv_flags		&= ~IFF_TX_SKB_SHARING;
 	dev->features		|= NETIF_F_LLTX;
 	dev->netdev_ops		= &l2tp_eth_netdev_ops;
 	dev->destructor		= free_netdev;
 }

 static void l2tp_eth_dev_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
 {
 	struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
 	struct net_device *dev = spriv->dev;
 	struct l2tp_eth *priv = netdev_priv(dev);

 	if (session->debug & L2TP_MSG_DATA) {
 		unsigned int length;

 		length = min(32u, skb->len);
 		if (!pskb_may_pull(skb, length))
 			goto error;

 		pr_debug("%s: eth recv\n", session->name);
 		print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, skb->data, length);
 	}

 	if (!pskb_may_pull(skb, ETH_HLEN))
 		goto error;

 	secpath_reset(skb);

 	/* checksums verified by L2TP */
 	skb->ip_summed = CHECKSUM_NONE;

 	skb_dst_drop(skb);
 	nf_reset(skb);

 	if (dev_forward_skb(dev, skb) == NET_RX_SUCCESS) {
 		atomic_long_inc(&priv->rx_packets);
 		atomic_long_add(data_len, &priv->rx_bytes);
 	} else {
 		atomic_long_inc(&priv->rx_errors);
 	}
 	return;

 error:
 	atomic_long_inc(&priv->rx_errors);
 	kfree_skb(skb);
 }

 static void l2tp_eth_delete(struct l2tp_session *session)
 {
 	struct l2tp_eth_sess *spriv;
 	struct net_device *dev;

 	if (session) {
 		spriv = l2tp_session_priv(session);
 		dev = spriv->dev;
 		if (dev) {
 			unregister_netdev(dev);
 			spriv->dev = NULL;
 			module_put(THIS_MODULE);
 		}
 	}
 }

 #if IS_ENABLED(CONFIG_L2TP_DEBUGFS)
 static void l2tp_eth_show(struct seq_file *m, void *arg)
 {
 	struct l2tp_session *session = arg;
 	struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
 	struct net_device *dev = spriv->dev;

 	seq_printf(m, "   interface %s\n", dev->name);
 }
 #endif

 static int l2tp_eth_create(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg)
 {
 	struct net_device *dev;
 	char name[IFNAMSIZ];
 	struct l2tp_tunnel *tunnel;
 	struct l2tp_session *session;
 	struct l2tp_eth *priv;
 	struct l2tp_eth_sess *spriv;
 	int rc;
 	struct l2tp_eth_net *pn;

 	tunnel = l2tp_tunnel_find(net, tunnel_id);
 	if (!tunnel) {
 		rc = -ENODEV;
 		goto out;
 	}

 	session = l2tp_session_find(net, tunnel, session_id);
 	if (session) {
 		rc = -EEXIST;
 		goto out;
 	}

 	if (cfg->ifname) {
 		dev = dev_get_by_name(net, cfg->ifname);
 		if (dev) {
 			dev_put(dev);
 			rc = -EEXIST;
 			goto out;
 		}
 		strlcpy(name, cfg->ifname, IFNAMSIZ);
 	} else
 		strcpy(name, L2TP_ETH_DEV_NAME);

 	session = l2tp_session_create(sizeof(*spriv), tunnel, session_id,
 				      peer_session_id, cfg);
 	if (!session) {
 		rc = -ENOMEM;
 		goto out;
 	}

 	dev = alloc_netdev(sizeof(*priv), name, NET_NAME_UNKNOWN,
 			   l2tp_eth_dev_setup);
 	if (!dev) {
 		rc = -ENOMEM;
 		goto out_del_session;
 	}

 	dev_net_set(dev, net);
 	if (session->mtu == 0)
 		session->mtu = dev->mtu - session->hdr_len;
 	dev->mtu = session->mtu;
 	dev->needed_headroom += session->hdr_len;
 	dev->min_mtu = 0;
 	dev->max_mtu = ETH_MAX_MTU;

 	priv = netdev_priv(dev);
 	priv->dev = dev;
 	priv->session = session;
 	INIT_LIST_HEAD(&priv->list);

 	priv->tunnel_sock = tunnel->sock;
 	session->recv_skb = l2tp_eth_dev_recv;
 	session->session_close = l2tp_eth_delete;
 #if IS_ENABLED(CONFIG_L2TP_DEBUGFS)
 	session->show = l2tp_eth_show;
 #endif

 	spriv = l2tp_session_priv(session);
 	spriv->dev = dev;

 	rc = register_netdev(dev);
 	if (rc < 0)
 		goto out_del_dev;

 	__module_get(THIS_MODULE);
 	/* Must be done after register_netdev() */
 	strlcpy(session->ifname, dev->name, IFNAMSIZ);

 	dev_hold(dev);
 	pn = l2tp_eth_pernet(dev_net(dev));
 	spin_lock(&pn->l2tp_eth_lock);
 	list_add(&priv->list, &pn->l2tp_eth_dev_list);
 	spin_unlock(&pn->l2tp_eth_lock);

 	return 0;

 out_del_dev:
 	free_netdev(dev);
 	spriv->dev = NULL;
 out_del_session:
 	l2tp_session_delete(session);
 out:
 	return rc;
 }

 static __net_init int l2tp_eth_init_net(struct net *net)
 {
 	struct l2tp_eth_net *pn = net_generic(net, l2tp_eth_net_id);

 	INIT_LIST_HEAD(&pn->l2tp_eth_dev_list);
 	spin_lock_init(&pn->l2tp_eth_lock);

 	return 0;
 }

 static struct pernet_operations l2tp_eth_net_ops = {
 	.init = l2tp_eth_init_net,
 	.id   = &l2tp_eth_net_id,
 	.size = sizeof(struct l2tp_eth_net),
 };


 static const struct l2tp_nl_cmd_ops l2tp_eth_nl_cmd_ops = {
 	.session_create	= l2tp_eth_create,
 	.session_delete	= l2tp_session_delete,
 };


 static int __init l2tp_eth_init(void)
 {
 	int err = 0;

 	err = l2tp_nl_register_ops(L2TP_PWTYPE_ETH, &l2tp_eth_nl_cmd_ops);
 	if (err)
 		goto out;

 	err = register_pernet_device(&l2tp_eth_net_ops);
 	if (err)
 		goto out_unreg;

 	pr_info("L2TP ethernet pseudowire support (L2TPv3)\n");

 	return 0;

 out_unreg:
 	l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
 out:
 	return err;
 }

 static void __exit l2tp_eth_exit(void)
 {
 	unregister_pernet_device(&l2tp_eth_net_ops);
 	l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
 }

 module_init(l2tp_eth_init);
 module_exit(l2tp_eth_exit);

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
 MODULE_DESCRIPTION("L2TP ethernet pseudowire driver");
 MODULE_VERSION("1.0");
 MODULE_ALIAS_L2TP_PWTYPE(5);
	/*
	* L2TPv3 ethernet pseudowire driver
	*
	* Copyright (c) 2008,2009,2010 Katalix Systems Ltd
	*
	* 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.
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/module.h>
	#include <linux/skbuff.h>
	#include <linux/socket.h>
	#include <linux/hash.h>
	#include <linux/l2tp.h>
	#include <linux/in.h>
	#include <linux/etherdevice.h>
	#include <linux/spinlock.h>
	#include <net/sock.h>
	#include <net/ip.h>
	#include <net/icmp.h>
	#include <net/udp.h>
	#include <net/inet_common.h>
	#include <net/inet_hashtables.h>
	#include <net/tcp_states.h>
	#include <net/protocol.h>
	#include <net/xfrm.h>
	#include <net/net_namespace.h>
	#include <net/netns/generic.h>

	#include "l2tp_core.h"

	/* Default device name. May be overridden by name specified by user */
	#define L2TP_ETH_DEV_NAME "l2tpeth%d"

	/* via netdev_priv() */
	struct l2tp_eth {
	struct net_device *dev;
	struct sock *tunnel_sock;
	struct l2tp_session *session;
	struct list_head list;
	atomic_long_t tx_bytes;
	atomic_long_t tx_packets;
	atomic_long_t tx_dropped;
	atomic_long_t rx_bytes;
	atomic_long_t rx_packets;
	atomic_long_t rx_errors;
	};

	/* via l2tp_session_priv() */
	struct l2tp_eth_sess {
	struct net_device *dev;
	};

	/* per-net private data for this module */
	static unsigned int l2tp_eth_net_id;
	struct l2tp_eth_net {
	struct list_head l2tp_eth_dev_list;
	spinlock_t l2tp_eth_lock;
	};

	static inline struct l2tp_eth_net l2tp_eth_pernet(struct net net)
	{
	return net_generic(net, l2tp_eth_net_id);
	}

	static int l2tp_eth_dev_init(struct net_device *dev)
	{
	struct l2tp_eth *priv = netdev_priv(dev);

	priv->dev = dev;
	eth_hw_addr_random(dev);
	eth_broadcast_addr(dev->broadcast);
	netdev_lockdep_set_classes(dev);

	return 0;
	}

	static void l2tp_eth_dev_uninit(struct net_device *dev)
	{
	struct l2tp_eth *priv = netdev_priv(dev);
	struct l2tp_eth_net *pn = l2tp_eth_pernet(dev_net(dev));

	spin_lock(&pn->l2tp_eth_lock);
	list_del_init(&priv->list);
	spin_unlock(&pn->l2tp_eth_lock);
	dev_put(dev);
	}

	static int l2tp_eth_dev_xmit(struct sk_buff skb, struct net_device dev)
	{
	struct l2tp_eth *priv = netdev_priv(dev);
	struct l2tp_session *session = priv->session;
	unsigned int len = skb->len;
	int ret = l2tp_xmit_skb(session, skb, session->hdr_len);

	if (likely(ret == NET_XMIT_SUCCESS)) {
	atomic_long_add(len, &priv->tx_bytes);
	atomic_long_inc(&priv->tx_packets);
	} else {
	atomic_long_inc(&priv->tx_dropped);
	}
	return NETDEV_TX_OK;
	}

	static void l2tp_eth_get_stats64(struct net_device *dev,
	struct rtnl_link_stats64 *stats)
	{
	struct l2tp_eth *priv = netdev_priv(dev);

	stats->tx_bytes = atomic_long_read(&priv->tx_bytes);
	stats->tx_packets = atomic_long_read(&priv->tx_packets);
	stats->tx_dropped = atomic_long_read(&priv->tx_dropped);
	stats->rx_bytes = atomic_long_read(&priv->rx_bytes);
	stats->rx_packets = atomic_long_read(&priv->rx_packets);
	stats->rx_errors = atomic_long_read(&priv->rx_errors);
	}

	static const struct net_device_ops l2tp_eth_netdev_ops = {
	.ndo_init = l2tp_eth_dev_init,
	.ndo_uninit = l2tp_eth_dev_uninit,
	.ndo_start_xmit = l2tp_eth_dev_xmit,
	.ndo_get_stats64 = l2tp_eth_get_stats64,
	.ndo_set_mac_address = eth_mac_addr,
	};

	static void l2tp_eth_dev_setup(struct net_device *dev)
	{
	ether_setup(dev);
	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
	dev->features \|= NETIF_F_LLTX;
	dev->netdev_ops = &l2tp_eth_netdev_ops;
	dev->destructor = free_netdev;
	}

	static void l2tp_eth_dev_recv(struct l2tp_session session, struct sk_buff skb, int data_len)
	{
	struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
	struct net_device *dev = spriv->dev;
	struct l2tp_eth *priv = netdev_priv(dev);

	if (session->debug & L2TP_MSG_DATA) {
	unsigned int length;

	length = min(32u, skb->len);
	if (!pskb_may_pull(skb, length))
	goto error;

	pr_debug("%s: eth recv\n", session->name);
	print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, skb->data, length);
	}

	if (!pskb_may_pull(skb, ETH_HLEN))
	goto error;

	secpath_reset(skb);

	/* checksums verified by L2TP */
	skb->ip_summed = CHECKSUM_NONE;

	skb_dst_drop(skb);
	nf_reset(skb);

	if (dev_forward_skb(dev, skb) == NET_RX_SUCCESS) {
	atomic_long_inc(&priv->rx_packets);
	atomic_long_add(data_len, &priv->rx_bytes);
	} else {
	atomic_long_inc(&priv->rx_errors);
	}
	return;

	error:
	atomic_long_inc(&priv->rx_errors);
	kfree_skb(skb);
	}

	static void l2tp_eth_delete(struct l2tp_session *session)
	{
	struct l2tp_eth_sess *spriv;
	struct net_device *dev;

	if (session) {
	spriv = l2tp_session_priv(session);
	dev = spriv->dev;
	if (dev) {
	unregister_netdev(dev);
	spriv->dev = NULL;
	module_put(THIS_MODULE);
	}
	}
	}

	#if IS_ENABLED(CONFIG_L2TP_DEBUGFS)
	static void l2tp_eth_show(struct seq_file m, void arg)
	{
	struct l2tp_session *session = arg;
	struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
	struct net_device *dev = spriv->dev;

	seq_printf(m, " interface %s\n", dev->name);
	}
	#endif

	static int l2tp_eth_create(struct net net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg cfg)
	{
	struct net_device *dev;
	char name[IFNAMSIZ];
	struct l2tp_tunnel *tunnel;
	struct l2tp_session *session;
	struct l2tp_eth *priv;
	struct l2tp_eth_sess *spriv;
	int rc;
	struct l2tp_eth_net *pn;

	tunnel = l2tp_tunnel_find(net, tunnel_id);
	if (!tunnel) {
	rc = -ENODEV;
	goto out;
	}

	session = l2tp_session_find(net, tunnel, session_id);
	if (session) {
	rc = -EEXIST;
	goto out;
	}

	if (cfg->ifname) {
	dev = dev_get_by_name(net, cfg->ifname);
	if (dev) {
	dev_put(dev);
	rc = -EEXIST;
	goto out;
	}
	strlcpy(name, cfg->ifname, IFNAMSIZ);
	} else
	strcpy(name, L2TP_ETH_DEV_NAME);

	session = l2tp_session_create(sizeof(*spriv), tunnel, session_id,
	peer_session_id, cfg);
	if (!session) {
	rc = -ENOMEM;
	goto out;
	}

	dev = alloc_netdev(sizeof(*priv), name, NET_NAME_UNKNOWN,
	l2tp_eth_dev_setup);
	if (!dev) {
	rc = -ENOMEM;
	goto out_del_session;
	}

	dev_net_set(dev, net);
	if (session->mtu == 0)
	session->mtu = dev->mtu - session->hdr_len;
	dev->mtu = session->mtu;
	dev->needed_headroom += session->hdr_len;
	dev->min_mtu = 0;
	dev->max_mtu = ETH_MAX_MTU;

	priv = netdev_priv(dev);
	priv->dev = dev;
	priv->session = session;
	INIT_LIST_HEAD(&priv->list);

	priv->tunnel_sock = tunnel->sock;
	session->recv_skb = l2tp_eth_dev_recv;
	session->session_close = l2tp_eth_delete;
	#if IS_ENABLED(CONFIG_L2TP_DEBUGFS)
	session->show = l2tp_eth_show;
	#endif

	spriv = l2tp_session_priv(session);
	spriv->dev = dev;

	rc = register_netdev(dev);
	if (rc < 0)
	goto out_del_dev;

	__module_get(THIS_MODULE);
	/* Must be done after register_netdev() */
	strlcpy(session->ifname, dev->name, IFNAMSIZ);

	dev_hold(dev);
	pn = l2tp_eth_pernet(dev_net(dev));
	spin_lock(&pn->l2tp_eth_lock);
	list_add(&priv->list, &pn->l2tp_eth_dev_list);
	spin_unlock(&pn->l2tp_eth_lock);

	return 0;

	out_del_dev:
	free_netdev(dev);
	spriv->dev = NULL;
	out_del_session:
	l2tp_session_delete(session);
	out:
	return rc;
	}

	static __net_init int l2tp_eth_init_net(struct net *net)
	{
	struct l2tp_eth_net *pn = net_generic(net, l2tp_eth_net_id);

	INIT_LIST_HEAD(&pn->l2tp_eth_dev_list);
	spin_lock_init(&pn->l2tp_eth_lock);

	return 0;
	}

	static struct pernet_operations l2tp_eth_net_ops = {
	.init = l2tp_eth_init_net,
	.id = &l2tp_eth_net_id,
	.size = sizeof(struct l2tp_eth_net),
	};


	static const struct l2tp_nl_cmd_ops l2tp_eth_nl_cmd_ops = {
	.session_create = l2tp_eth_create,
	.session_delete = l2tp_session_delete,
	};


	static int __init l2tp_eth_init(void)
	{
	int err = 0;

	err = l2tp_nl_register_ops(L2TP_PWTYPE_ETH, &l2tp_eth_nl_cmd_ops);
	if (err)
	goto out;

	err = register_pernet_device(&l2tp_eth_net_ops);
	if (err)
	goto out_unreg;

	pr_info("L2TP ethernet pseudowire support (L2TPv3)\n");

	return 0;

	out_unreg:
	l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
	out:
	return err;
	}

	static void __exit l2tp_eth_exit(void)
	{
	unregister_pernet_device(&l2tp_eth_net_ops);
	l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
	}

	module_init(l2tp_eth_init);
	module_exit(l2tp_eth_exit);

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
	MODULE_DESCRIPTION("L2TP ethernet pseudowire driver");
	MODULE_VERSION("1.0");
	MODULE_ALIAS_L2TP_PWTYPE(5);