/* * 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 struct lock_class_key l2tp_eth_tx_busylock; 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); dev->qdisc_tx_busylock = &l2tp_eth_tx_busylock; 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 struct rtnl_link_stats64 *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); return stats; } static 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 defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE) 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; 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 defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE) 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");