--- /dev/null
+/** -*- linux-c -*- ***********************************************************
+ * Linux PPP over Ethernet (PPPoX/PPPoE) Sockets
+ *
+ * PPPoX --- Generic PPP encapsulation socket family
+ * PPPoE --- PPP over Ethernet (RFC 2516)
+ *
+ *
+ * Version: 0.7.0
+ *
+ * 070228 : Fix to allow multiple sessions with same remote MAC and same
+ * session id by including the local device ifindex in the
+ * tuple identifying a session. This also ensures packets can't
+ * be injected into a session from interfaces other than the one
+ * specified by userspace. Florian Zumbiehl <florz@florz.de>
+ * (Oh, BTW, this one is YYMMDD, in case you were wondering ...)
+ * 220102 : Fix module use count on failure in pppoe_create, pppox_sk -acme
+ * 030700 : Fixed connect logic to allow for disconnect.
+ * 270700 : Fixed potential SMP problems; we must protect against
+ * simultaneous invocation of ppp_input
+ * and ppp_unregister_channel.
+ * 040800 : Respect reference count mechanisms on net-devices.
+ * 200800 : fix kfree(skb) in pppoe_rcv (acme)
+ * Module reference count is decremented in the right spot now,
+ * guards against sock_put not actually freeing the sk
+ * in pppoe_release.
+ * 051000 : Initialization cleanup.
+ * 111100 : Fix recvmsg.
+ * 050101 : Fix PADT procesing.
+ * 140501 : Use pppoe_rcv_core to handle all backlog. (Alexey)
+ * 170701 : Do not lock_sock with rwlock held. (DaveM)
+ * Ignore discovery frames if user has socket
+ * locked. (DaveM)
+ * Ignore return value of dev_queue_xmit in __pppoe_xmit
+ * or else we may kfree an SKB twice. (DaveM)
+ * 190701 : When doing copies of skb's in __pppoe_xmit, always delete
+ * the original skb that was passed in on success, never on
+ * failure. Delete the copy of the skb on failure to avoid
+ * a memory leak.
+ * 081001 : Misc. cleanup (licence string, non-blocking, prevent
+ * reference of device on close).
+ * 121301 : New ppp channels interface; cannot unregister a channel
+ * from interrupts. Thus, we mark the socket as a ZOMBIE
+ * and do the unregistration later.
+ * 081002 : seq_file support for proc stuff -acme
+ * 111602 : Merge all 2.4 fixes into 2.5/2.6 tree. Label 2.5/2.6
+ * as version 0.7. Spacing cleanup.
+ * Author: Michal Ostrowski <mostrows@speakeasy.net>
+ * Contributors:
+ * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ * David S. Miller (davem@redhat.com)
+ *
+ * License:
+ * 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/string.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <linux/net.h>
+#include <linux/inetdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/init.h>
+#include <linux/if_ether.h>
+#include <linux/if_pppox.h>
+#include <linux/ppp_channel.h>
+#include <linux/ppp_defs.h>
+#include <linux/ppp-ioctl.h>
+#include <linux/notifier.h>
+#include <linux/file.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+#include <linux/nsproxy.h>
+#include <net/net_namespace.h>
+#include <net/netns/generic.h>
+#include <net/sock.h>
+
+#include <asm/uaccess.h>
+
+#define PPPOE_HASH_BITS 4
+#define PPPOE_HASH_SIZE (1 << PPPOE_HASH_BITS)
+#define PPPOE_HASH_MASK (PPPOE_HASH_SIZE - 1)
+
+static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb);
+
+static const struct proto_ops pppoe_ops;
+static const struct ppp_channel_ops pppoe_chan_ops;
+
+/* per-net private data for this module */
+static int pppoe_net_id __read_mostly;
+struct pppoe_net {
+ /*
+ * we could use _single_ hash table for all
+ * nets by injecting net id into the hash but
+ * it would increase hash chains and add
+ * a few additional math comparations messy
+ * as well, moreover in case of SMP less locking
+ * controversy here
+ */
+ struct pppox_sock *hash_table[PPPOE_HASH_SIZE];
+ rwlock_t hash_lock;
+};
+
+/*
+ * PPPoE could be in the following stages:
+ * 1) Discovery stage (to obtain remote MAC and Session ID)
+ * 2) Session stage (MAC and SID are known)
+ *
+ * Ethernet frames have a special tag for this but
+ * we use simpler approach based on session id
+ */
+static inline bool stage_session(__be16 sid)
+{
+ return sid != 0;
+}
+
+static inline struct pppoe_net *pppoe_pernet(struct net *net)
+{
+ BUG_ON(!net);
+
+ return net_generic(net, pppoe_net_id);
+}
+
+static inline int cmp_2_addr(struct pppoe_addr *a, struct pppoe_addr *b)
+{
+ return a->sid == b->sid && ether_addr_equal(a->remote, b->remote);
+}
+
+static inline int cmp_addr(struct pppoe_addr *a, __be16 sid, char *addr)
+{
+ return a->sid == sid && ether_addr_equal(a->remote, addr);
+}
+
+#if 8 % PPPOE_HASH_BITS
+#error 8 must be a multiple of PPPOE_HASH_BITS
+#endif
+
+static int hash_item(__be16 sid, unsigned char *addr)
+{
+ unsigned char hash = 0;
+ unsigned int i;
+
+ for (i = 0; i < ETH_ALEN; i++)
+ hash ^= addr[i];
+ for (i = 0; i < sizeof(sid_t) * 8; i += 8)
+ hash ^= (__force __u32)sid >> i;
+ for (i = 8; (i >>= 1) >= PPPOE_HASH_BITS;)
+ hash ^= hash >> i;
+
+ return hash & PPPOE_HASH_MASK;
+}
+
+/**********************************************************************
+ *
+ * Set/get/delete/rehash items (internal versions)
+ *
+ **********************************************************************/
+static struct pppox_sock *__get_item(struct pppoe_net *pn, __be16 sid,
+ unsigned char *addr, int ifindex)
+{
+ int hash = hash_item(sid, addr);
+ struct pppox_sock *ret;
+
+ ret = pn->hash_table[hash];
+ while (ret) {
+ if (cmp_addr(&ret->pppoe_pa, sid, addr) &&
+ ret->pppoe_ifindex == ifindex)
+ return ret;
+
+ ret = ret->next;
+ }
+
+ return NULL;
+}
+
+static int __set_item(struct pppoe_net *pn, struct pppox_sock *po)
+{
+ int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
+ struct pppox_sock *ret;
+
+ ret = pn->hash_table[hash];
+ while (ret) {
+ if (cmp_2_addr(&ret->pppoe_pa, &po->pppoe_pa) &&
+ ret->pppoe_ifindex == po->pppoe_ifindex)
+ return -EALREADY;
+
+ ret = ret->next;
+ }
+
+ po->next = pn->hash_table[hash];
+ pn->hash_table[hash] = po;
+
+ return 0;
+}
+
+static void __delete_item(struct pppoe_net *pn, __be16 sid,
+ char *addr, int ifindex)
+{
+ int hash = hash_item(sid, addr);
+ struct pppox_sock *ret, **src;
+
+ ret = pn->hash_table[hash];
+ src = &pn->hash_table[hash];
+
+ while (ret) {
+ if (cmp_addr(&ret->pppoe_pa, sid, addr) &&
+ ret->pppoe_ifindex == ifindex) {
+ *src = ret->next;
+ break;
+ }
+
+ src = &ret->next;
+ ret = ret->next;
+ }
+}
+
+/**********************************************************************
+ *
+ * Set/get/delete/rehash items
+ *
+ **********************************************************************/
+static inline struct pppox_sock *get_item(struct pppoe_net *pn, __be16 sid,
+ unsigned char *addr, int ifindex)
+{
+ struct pppox_sock *po;
+
+ read_lock_bh(&pn->hash_lock);
+ po = __get_item(pn, sid, addr, ifindex);
+ if (po)
+ sock_hold(sk_pppox(po));
+ read_unlock_bh(&pn->hash_lock);
+
+ return po;
+}
+
+static inline struct pppox_sock *get_item_by_addr(struct net *net,
+ struct sockaddr_pppox *sp)
+{
+ struct net_device *dev;
+ struct pppoe_net *pn;
+ struct pppox_sock *pppox_sock = NULL;
+
+ int ifindex;
+
+ rcu_read_lock();
+ dev = dev_get_by_name_rcu(net, sp->sa_addr.pppoe.dev);
+ if (dev) {
+ ifindex = dev->ifindex;
+ pn = pppoe_pernet(net);
+ pppox_sock = get_item(pn, sp->sa_addr.pppoe.sid,
+ sp->sa_addr.pppoe.remote, ifindex);
+ }
+ rcu_read_unlock();
+ return pppox_sock;
+}
+
+static inline void delete_item(struct pppoe_net *pn, __be16 sid,
+ char *addr, int ifindex)
+{
+ write_lock_bh(&pn->hash_lock);
+ __delete_item(pn, sid, addr, ifindex);
+ write_unlock_bh(&pn->hash_lock);
+}
+
+/***************************************************************************
+ *
+ * Handler for device events.
+ * Certain device events require that sockets be unconnected.
+ *
+ **************************************************************************/
+
+static void pppoe_flush_dev(struct net_device *dev)
+{
+ struct pppoe_net *pn;
+ int i;
+
+ pn = pppoe_pernet(dev_net(dev));
+ write_lock_bh(&pn->hash_lock);
+ for (i = 0; i < PPPOE_HASH_SIZE; i++) {
+ struct pppox_sock *po = pn->hash_table[i];
+ struct sock *sk;
+
+ while (po) {
+ while (po && po->pppoe_dev != dev) {
+ po = po->next;
+ }
+
+ if (!po)
+ break;
+
+ sk = sk_pppox(po);
+
+ /* We always grab the socket lock, followed by the
+ * hash_lock, in that order. Since we should hold the
+ * sock lock while doing any unbinding, we need to
+ * release the lock we're holding. Hold a reference to
+ * the sock so it doesn't disappear as we're jumping
+ * between locks.
+ */
+
+ sock_hold(sk);
+ write_unlock_bh(&pn->hash_lock);
+ lock_sock(sk);
+
+ if (po->pppoe_dev == dev &&
+ sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND | PPPOX_ZOMBIE)) {
+ pppox_unbind_sock(sk);
+ sk->sk_state = PPPOX_ZOMBIE;
+ sk->sk_state_change(sk);
+ po->pppoe_dev = NULL;
+ dev_put(dev);
+ }
+
+ release_sock(sk);
+ sock_put(sk);
+
+ /* Restart the process from the start of the current
+ * hash chain. We dropped locks so the world may have
+ * change from underneath us.
+ */
+
+ BUG_ON(pppoe_pernet(dev_net(dev)) == NULL);
+ write_lock_bh(&pn->hash_lock);
+ po = pn->hash_table[i];
+ }
+ }
+ write_unlock_bh(&pn->hash_lock);
+}
+
+static int pppoe_device_event(struct notifier_block *this,
+ unsigned long event, void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ /* Only look at sockets that are using this specific device. */
+ switch (event) {
+ case NETDEV_CHANGEADDR:
+ case NETDEV_CHANGEMTU:
+ /* A change in mtu or address is a bad thing, requiring
+ * LCP re-negotiation.
+ */
+
+ case NETDEV_GOING_DOWN:
+ case NETDEV_DOWN:
+ /* Find every socket on this device and kill it. */
+ pppoe_flush_dev(dev);
+ break;
+
+ default:
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block pppoe_notifier = {
+ .notifier_call = pppoe_device_event,
+};
+
+/************************************************************************
+ *
+ * Do the real work of receiving a PPPoE Session frame.
+ *
+ ***********************************************************************/
+static int pppoe_rcv_core(struct sock *sk, struct sk_buff *skb)
+{
+ struct pppox_sock *po = pppox_sk(sk);
+ struct pppox_sock *relay_po;
+
+ /* Backlog receive. Semantics of backlog rcv preclude any code from
+ * executing in lock_sock()/release_sock() bounds; meaning sk->sk_state
+ * can't change.
+ */
+
+ if (skb->pkt_type == PACKET_OTHERHOST)
+ goto abort_kfree;
+
+ if (sk->sk_state & PPPOX_BOUND) {
+ ppp_input(&po->chan, skb);
+ } else if (sk->sk_state & PPPOX_RELAY) {
+ relay_po = get_item_by_addr(sock_net(sk),
+ &po->pppoe_relay);
+ if (relay_po == NULL)
+ goto abort_kfree;
+
+ if ((sk_pppox(relay_po)->sk_state & PPPOX_CONNECTED) == 0)
+ goto abort_put;
+
+ if (!__pppoe_xmit(sk_pppox(relay_po), skb))
+ goto abort_put;
+ } else {
+ if (sock_queue_rcv_skb(sk, skb))
+ goto abort_kfree;
+ }
+
+ return NET_RX_SUCCESS;
+
+abort_put:
+ sock_put(sk_pppox(relay_po));
+
+abort_kfree:
+ kfree_skb(skb);
+ return NET_RX_DROP;
+}
+
+/************************************************************************
+ *
+ * Receive wrapper called in BH context.
+ *
+ ***********************************************************************/
+static int pppoe_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+{
+ struct pppoe_hdr *ph;
+ struct pppox_sock *po;
+ struct pppoe_net *pn;
+ int len;
+
+ skb = skb_share_check(skb, GFP_ATOMIC);
+ if (!skb)
+ goto out;
+
+ if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
+ goto drop;
+
+ ph = pppoe_hdr(skb);
+ len = ntohs(ph->length);
+
+ skb_pull_rcsum(skb, sizeof(*ph));
+ if (skb->len < len)
+ goto drop;
+
+ if (pskb_trim_rcsum(skb, len))
+ goto drop;
+
+ pn = pppoe_pernet(dev_net(dev));
+
+ /* Note that get_item does a sock_hold(), so sk_pppox(po)
+ * is known to be safe.
+ */
+ po = get_item(pn, ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
+ if (!po)
+ goto drop;
+
+ return sk_receive_skb(sk_pppox(po), skb, 0);
+
+drop:
+ kfree_skb(skb);
+out:
+ return NET_RX_DROP;
+}
+
+static void pppoe_unbind_sock_work(struct work_struct *work)
+{
+ struct pppox_sock *po = container_of(work, struct pppox_sock,
+ proto.pppoe.padt_work);
+ struct sock *sk = sk_pppox(po);
+
+ lock_sock(sk);
+ if (po->pppoe_dev) {
+ dev_put(po->pppoe_dev);
+ po->pppoe_dev = NULL;
+ }
+ pppox_unbind_sock(sk);
+ release_sock(sk);
+ sock_put(sk);
+}
+
+/************************************************************************
+ *
+ * Receive a PPPoE Discovery frame.
+ * This is solely for detection of PADT frames
+ *
+ ***********************************************************************/
+static int pppoe_disc_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+
+{
+ struct pppoe_hdr *ph;
+ struct pppox_sock *po;
+ struct pppoe_net *pn;
+
+ skb = skb_share_check(skb, GFP_ATOMIC);
+ if (!skb)
+ goto out;
+
+ if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
+ goto abort;
+
+ ph = pppoe_hdr(skb);
+ if (ph->code != PADT_CODE)
+ goto abort;
+
+ pn = pppoe_pernet(dev_net(dev));
+ po = get_item(pn, ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
+ if (po) {
+ struct sock *sk = sk_pppox(po);
+
+ bh_lock_sock(sk);
+
+ /* If the user has locked the socket, just ignore
+ * the packet. With the way two rcv protocols hook into
+ * one socket family type, we cannot (easily) distinguish
+ * what kind of SKB it is during backlog rcv.
+ */
+ if (sock_owned_by_user(sk) == 0) {
+ /* We're no longer connect at the PPPOE layer,
+ * and must wait for ppp channel to disconnect us.
+ */
+ sk->sk_state = PPPOX_ZOMBIE;
+ }
+
+ bh_unlock_sock(sk);
+ if (!schedule_work(&po->proto.pppoe.padt_work))
+ sock_put(sk);
+ }
+
+abort:
+ kfree_skb(skb);
+out:
+ return NET_RX_SUCCESS; /* Lies... :-) */
+}
+
+static struct packet_type pppoes_ptype __read_mostly = {
+ .type = cpu_to_be16(ETH_P_PPP_SES),
+ .func = pppoe_rcv,
+};
+
+static struct packet_type pppoed_ptype __read_mostly = {
+ .type = cpu_to_be16(ETH_P_PPP_DISC),
+ .func = pppoe_disc_rcv,
+};
+
+static struct proto pppoe_sk_proto __read_mostly = {
+ .name = "PPPOE",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct pppox_sock),
+};
+
+/***********************************************************************
+ *
+ * Initialize a new struct sock.
+ *
+ **********************************************************************/
+static int pppoe_create(struct net *net, struct socket *sock)
+{
+ struct sock *sk;
+
+ sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppoe_sk_proto);
+ if (!sk)
+ return -ENOMEM;
+
+ sock_init_data(sock, sk);
+
+ sock->state = SS_UNCONNECTED;
+ sock->ops = &pppoe_ops;
+
+ sk->sk_backlog_rcv = pppoe_rcv_core;
+ sk->sk_state = PPPOX_NONE;
+ sk->sk_type = SOCK_STREAM;
+ sk->sk_family = PF_PPPOX;
+ sk->sk_protocol = PX_PROTO_OE;
+
+ return 0;
+}
+
+static int pppoe_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ struct pppox_sock *po;
+ struct pppoe_net *pn;
+ struct net *net = NULL;
+
+ if (!sk)
+ return 0;
+
+ lock_sock(sk);
+ if (sock_flag(sk, SOCK_DEAD)) {
+ release_sock(sk);
+ return -EBADF;
+ }
+
+ po = pppox_sk(sk);
+
+ if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND | PPPOX_ZOMBIE)) {
+ dev_put(po->pppoe_dev);
+ po->pppoe_dev = NULL;
+ }
+
+ pppox_unbind_sock(sk);
+
+ /* Signal the death of the socket. */
+ sk->sk_state = PPPOX_DEAD;
+
+ net = sock_net(sk);
+ pn = pppoe_pernet(net);
+
+ /*
+ * protect "po" from concurrent updates
+ * on pppoe_flush_dev
+ */
+ delete_item(pn, po->pppoe_pa.sid, po->pppoe_pa.remote,
+ po->pppoe_ifindex);
+
+ sock_orphan(sk);
+ sock->sk = NULL;
+
+ skb_queue_purge(&sk->sk_receive_queue);
+ release_sock(sk);
+ sock_put(sk);
+
+ return 0;
+}
+
+static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
+ int sockaddr_len, int flags)
+{
+ struct sock *sk = sock->sk;
+ struct sockaddr_pppox *sp = (struct sockaddr_pppox *)uservaddr;
+ struct pppox_sock *po = pppox_sk(sk);
+ struct net_device *dev = NULL;
+ struct pppoe_net *pn;
+ struct net *net = NULL;
+ int error;
+
+ lock_sock(sk);
+
+ INIT_WORK(&po->proto.pppoe.padt_work, pppoe_unbind_sock_work);
+
+ error = -EINVAL;
+ if (sp->sa_protocol != PX_PROTO_OE)
+ goto end;
+
+ /* Check for already bound sockets */
+ error = -EBUSY;
+ if ((sk->sk_state & PPPOX_CONNECTED) &&
+ stage_session(sp->sa_addr.pppoe.sid))
+ goto end;
+
+ /* Check for already disconnected sockets, on attempts to disconnect */
+ error = -EALREADY;
+ if ((sk->sk_state & PPPOX_DEAD) &&
+ !stage_session(sp->sa_addr.pppoe.sid))
+ goto end;
+
+ error = 0;
+
+ /* Delete the old binding */
+ if (stage_session(po->pppoe_pa.sid)) {
+ pppox_unbind_sock(sk);
+ pn = pppoe_pernet(sock_net(sk));
+ delete_item(pn, po->pppoe_pa.sid,
+ po->pppoe_pa.remote, po->pppoe_ifindex);
+ if (po->pppoe_dev) {
+ dev_put(po->pppoe_dev);
+ po->pppoe_dev = NULL;
+ }
+
+ memset(sk_pppox(po) + 1, 0,
+ sizeof(struct pppox_sock) - sizeof(struct sock));
+ sk->sk_state = PPPOX_NONE;
+ }
+
+ /* Re-bind in session stage only */
+ if (stage_session(sp->sa_addr.pppoe.sid)) {
+ error = -ENODEV;
+ net = sock_net(sk);
+ dev = dev_get_by_name(net, sp->sa_addr.pppoe.dev);
+ if (!dev)
+ goto err_put;
+
+ po->pppoe_dev = dev;
+ po->pppoe_ifindex = dev->ifindex;
+ pn = pppoe_pernet(net);
+ if (!(dev->flags & IFF_UP)) {
+ goto err_put;
+ }
+
+ memcpy(&po->pppoe_pa,
+ &sp->sa_addr.pppoe,
+ sizeof(struct pppoe_addr));
+
+ write_lock_bh(&pn->hash_lock);
+ error = __set_item(pn, po);
+ write_unlock_bh(&pn->hash_lock);
+ if (error < 0)
+ goto err_put;
+
+ po->chan.hdrlen = (sizeof(struct pppoe_hdr) +
+ dev->hard_header_len);
+
+ po->chan.mtu = dev->mtu - sizeof(struct pppoe_hdr) - 2;
+ po->chan.private = sk;
+ po->chan.ops = &pppoe_chan_ops;
+
+ error = ppp_register_net_channel(dev_net(dev), &po->chan);
+ if (error) {
+ delete_item(pn, po->pppoe_pa.sid,
+ po->pppoe_pa.remote, po->pppoe_ifindex);
+ goto err_put;
+ }
+
+ sk->sk_state = PPPOX_CONNECTED;
+ }
+
+ po->num = sp->sa_addr.pppoe.sid;
+
+end:
+ release_sock(sk);
+ return error;
+err_put:
+ if (po->pppoe_dev) {
+ dev_put(po->pppoe_dev);
+ po->pppoe_dev = NULL;
+ }
+ goto end;
+}
+
+static int pppoe_getname(struct socket *sock, struct sockaddr *uaddr,
+ int *usockaddr_len, int peer)
+{
+ int len = sizeof(struct sockaddr_pppox);
+ struct sockaddr_pppox sp;
+
+ sp.sa_family = AF_PPPOX;
+ sp.sa_protocol = PX_PROTO_OE;
+ memcpy(&sp.sa_addr.pppoe, &pppox_sk(sock->sk)->pppoe_pa,
+ sizeof(struct pppoe_addr));
+
+ memcpy(uaddr, &sp, len);
+
+ *usockaddr_len = len;
+
+ return 0;
+}
+
+static int pppoe_ioctl(struct socket *sock, unsigned int cmd,
+ unsigned long arg)
+{
+ struct sock *sk = sock->sk;
+ struct pppox_sock *po = pppox_sk(sk);
+ int val;
+ int err;
+
+ switch (cmd) {
+ case PPPIOCGMRU:
+ err = -ENXIO;
+ if (!(sk->sk_state & PPPOX_CONNECTED))
+ break;
+
+ err = -EFAULT;
+ if (put_user(po->pppoe_dev->mtu -
+ sizeof(struct pppoe_hdr) -
+ PPP_HDRLEN,
+ (int __user *)arg))
+ break;
+ err = 0;
+ break;
+
+ case PPPIOCSMRU:
+ err = -ENXIO;
+ if (!(sk->sk_state & PPPOX_CONNECTED))
+ break;
+
+ err = -EFAULT;
+ if (get_user(val, (int __user *)arg))
+ break;
+
+ if (val < (po->pppoe_dev->mtu
+ - sizeof(struct pppoe_hdr)
+ - PPP_HDRLEN))
+ err = 0;
+ else
+ err = -EINVAL;
+ break;
+
+ case PPPIOCSFLAGS:
+ err = -EFAULT;
+ if (get_user(val, (int __user *)arg))
+ break;
+ err = 0;
+ break;
+
+ case PPPOEIOCSFWD:
+ {
+ struct pppox_sock *relay_po;
+
+ err = -EBUSY;
+ if (sk->sk_state & (PPPOX_BOUND | PPPOX_ZOMBIE | PPPOX_DEAD))
+ break;
+
+ err = -ENOTCONN;
+ if (!(sk->sk_state & PPPOX_CONNECTED))
+ break;
+
+ /* PPPoE address from the user specifies an outbound
+ PPPoE address which frames are forwarded to */
+ err = -EFAULT;
+ if (copy_from_user(&po->pppoe_relay,
+ (void __user *)arg,
+ sizeof(struct sockaddr_pppox)))
+ break;
+
+ err = -EINVAL;
+ if (po->pppoe_relay.sa_family != AF_PPPOX ||
+ po->pppoe_relay.sa_protocol != PX_PROTO_OE)
+ break;
+
+ /* Check that the socket referenced by the address
+ actually exists. */
+ relay_po = get_item_by_addr(sock_net(sk), &po->pppoe_relay);
+ if (!relay_po)
+ break;
+
+ sock_put(sk_pppox(relay_po));
+ sk->sk_state |= PPPOX_RELAY;
+ err = 0;
+ break;
+ }
+
+ case PPPOEIOCDFWD:
+ err = -EALREADY;
+ if (!(sk->sk_state & PPPOX_RELAY))
+ break;
+
+ sk->sk_state &= ~PPPOX_RELAY;
+ err = 0;
+ break;
+
+ default:
+ err = -ENOTTY;
+ }
+
+ return err;
+}
+
+static int pppoe_sendmsg(struct socket *sock, struct msghdr *m,
+ size_t total_len)
+{
+ struct sk_buff *skb;
+ struct sock *sk = sock->sk;
+ struct pppox_sock *po = pppox_sk(sk);
+ int error;
+ struct pppoe_hdr hdr;
+ struct pppoe_hdr *ph;
+ struct net_device *dev;
+ char *start;
+
+ lock_sock(sk);
+ if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) {
+ error = -ENOTCONN;
+ goto end;
+ }
+
+ hdr.ver = 1;
+ hdr.type = 1;
+ hdr.code = 0;
+ hdr.sid = po->num;
+
+ dev = po->pppoe_dev;
+
+ error = -EMSGSIZE;
+ if (total_len > (dev->mtu + dev->hard_header_len))
+ goto end;
+
+
+ skb = sock_wmalloc(sk, total_len + dev->hard_header_len + 32,
+ 0, GFP_KERNEL);
+ if (!skb) {
+ error = -ENOMEM;
+ goto end;
+ }
+
+ /* Reserve space for headers. */
+ skb_reserve(skb, dev->hard_header_len);
+ skb_reset_network_header(skb);
+
+ skb->dev = dev;
+
+ skb->priority = sk->sk_priority;
+ skb->protocol = cpu_to_be16(ETH_P_PPP_SES);
+
+ ph = (struct pppoe_hdr *)skb_put(skb, total_len + sizeof(struct pppoe_hdr));
+ start = (char *)&ph->tag[0];
+
+ error = memcpy_from_msg(start, m, total_len);
+ if (error < 0) {
+ kfree_skb(skb);
+ goto end;
+ }
+
+ error = total_len;
+ dev_hard_header(skb, dev, ETH_P_PPP_SES,
+ po->pppoe_pa.remote, NULL, total_len);
+
+ memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
+
+ ph->length = htons(total_len);
+
+ dev_queue_xmit(skb);
+
+end:
+ release_sock(sk);
+ return error;
+}
+
+/************************************************************************
+ *
+ * xmit function for internal use.
+ *
+ ***********************************************************************/
+static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb)
+{
+ struct pppox_sock *po = pppox_sk(sk);
+ struct net_device *dev = po->pppoe_dev;
+ struct pppoe_hdr *ph;
+ int data_len = skb->len;
+
+ /* The higher-level PPP code (ppp_unregister_channel()) ensures the PPP
+ * xmit operations conclude prior to an unregistration call. Thus
+ * sk->sk_state cannot change, so we don't need to do lock_sock().
+ * But, we also can't do a lock_sock since that introduces a potential
+ * deadlock as we'd reverse the lock ordering used when calling
+ * ppp_unregister_channel().
+ */
+
+ if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
+ goto abort;
+
+ if (!dev)
+ goto abort;
+
+ /* Copy the data if there is no space for the header or if it's
+ * read-only.
+ */
+ if (skb_cow_head(skb, sizeof(*ph) + dev->hard_header_len))
+ goto abort;
+
+ __skb_push(skb, sizeof(*ph));
+ skb_reset_network_header(skb);
+
+ ph = pppoe_hdr(skb);
+ ph->ver = 1;
+ ph->type = 1;
+ ph->code = 0;
+ ph->sid = po->num;
+ ph->length = htons(data_len);
+
+ skb->protocol = cpu_to_be16(ETH_P_PPP_SES);
+ skb->dev = dev;
+
+ dev_hard_header(skb, dev, ETH_P_PPP_SES,
+ po->pppoe_pa.remote, NULL, data_len);
+
+ dev_queue_xmit(skb);
+ return 1;
+
+abort:
+ kfree_skb(skb);
+ return 1;
+}
+
+/************************************************************************
+ *
+ * xmit function called by generic PPP driver
+ * sends PPP frame over PPPoE socket
+ *
+ ***********************************************************************/
+static int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb)
+{
+ struct sock *sk = (struct sock *)chan->private;
+ return __pppoe_xmit(sk, skb);
+}
+
+static const struct ppp_channel_ops pppoe_chan_ops = {
+ .start_xmit = pppoe_xmit,
+};
+
+static int pppoe_recvmsg(struct socket *sock, struct msghdr *m,
+ size_t total_len, int flags)
+{
+ struct sock *sk = sock->sk;
+ struct sk_buff *skb;
+ int error = 0;
+
+ if (sk->sk_state & PPPOX_BOUND) {
+ error = -EIO;
+ goto end;
+ }
+
+ skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
+ flags & MSG_DONTWAIT, &error);
+ if (error < 0)
+ goto end;
+
+ if (skb) {
+ total_len = min_t(size_t, total_len, skb->len);
+ error = skb_copy_datagram_msg(skb, 0, m, total_len);
+ if (error == 0) {
+ consume_skb(skb);
+ return total_len;
+ }
+ }
+
+ kfree_skb(skb);
+end:
+ return error;
+}
+
+#ifdef CONFIG_PROC_FS
+static int pppoe_seq_show(struct seq_file *seq, void *v)
+{
+ struct pppox_sock *po;
+ char *dev_name;
+
+ if (v == SEQ_START_TOKEN) {
+ seq_puts(seq, "Id Address Device\n");
+ goto out;
+ }
+
+ po = v;
+ dev_name = po->pppoe_pa.dev;
+
+ seq_printf(seq, "%08X %pM %8s\n",
+ po->pppoe_pa.sid, po->pppoe_pa.remote, dev_name);
+out:
+ return 0;
+}
+
+static inline struct pppox_sock *pppoe_get_idx(struct pppoe_net *pn, loff_t pos)
+{
+ struct pppox_sock *po;
+ int i;
+
+ for (i = 0; i < PPPOE_HASH_SIZE; i++) {
+ po = pn->hash_table[i];
+ while (po) {
+ if (!pos--)
+ goto out;
+ po = po->next;
+ }
+ }
+
+out:
+ return po;
+}
+
+static void *pppoe_seq_start(struct seq_file *seq, loff_t *pos)
+ __acquires(pn->hash_lock)
+{
+ struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
+ loff_t l = *pos;
+
+ read_lock_bh(&pn->hash_lock);
+ return l ? pppoe_get_idx(pn, --l) : SEQ_START_TOKEN;
+}
+
+static void *pppoe_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
+ struct pppox_sock *po;
+
+ ++*pos;
+ if (v == SEQ_START_TOKEN) {
+ po = pppoe_get_idx(pn, 0);
+ goto out;
+ }
+ po = v;
+ if (po->next)
+ po = po->next;
+ else {
+ int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
+
+ po = NULL;
+ while (++hash < PPPOE_HASH_SIZE) {
+ po = pn->hash_table[hash];
+ if (po)
+ break;
+ }
+ }
+
+out:
+ return po;
+}
+
+static void pppoe_seq_stop(struct seq_file *seq, void *v)
+ __releases(pn->hash_lock)
+{
+ struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
+ read_unlock_bh(&pn->hash_lock);
+}
+
+static const struct seq_operations pppoe_seq_ops = {
+ .start = pppoe_seq_start,
+ .next = pppoe_seq_next,
+ .stop = pppoe_seq_stop,
+ .show = pppoe_seq_show,
+};
+
+static int pppoe_seq_open(struct inode *inode, struct file *file)
+{
+ return seq_open_net(inode, file, &pppoe_seq_ops,
+ sizeof(struct seq_net_private));
+}
+
+static const struct file_operations pppoe_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = pppoe_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release_net,
+};
+
+#endif /* CONFIG_PROC_FS */
+
+static const struct proto_ops pppoe_ops = {
+ .family = AF_PPPOX,
+ .owner = THIS_MODULE,
+ .release = pppoe_release,
+ .bind = sock_no_bind,
+ .connect = pppoe_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = pppoe_getname,
+ .poll = datagram_poll,
+ .listen = sock_no_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = sock_no_setsockopt,
+ .getsockopt = sock_no_getsockopt,
+ .sendmsg = pppoe_sendmsg,
+ .recvmsg = pppoe_recvmsg,
+ .mmap = sock_no_mmap,
+ .ioctl = pppox_ioctl,
+};
+
+static const struct pppox_proto pppoe_proto = {
+ .create = pppoe_create,
+ .ioctl = pppoe_ioctl,
+ .owner = THIS_MODULE,
+};
+
+static __net_init int pppoe_init_net(struct net *net)
+{
+ struct pppoe_net *pn = pppoe_pernet(net);
+ struct proc_dir_entry *pde;
+
+ rwlock_init(&pn->hash_lock);
+
+ pde = proc_create("pppoe", S_IRUGO, net->proc_net, &pppoe_seq_fops);
+#ifdef CONFIG_PROC_FS
+ if (!pde)
+ return -ENOMEM;
+#endif
+
+ return 0;
+}
+
+static __net_exit void pppoe_exit_net(struct net *net)
+{
+ remove_proc_entry("pppoe", net->proc_net);
+}
+
+static struct pernet_operations pppoe_net_ops = {
+ .init = pppoe_init_net,
+ .exit = pppoe_exit_net,
+ .id = &pppoe_net_id,
+ .size = sizeof(struct pppoe_net),
+};
+
+static int __init pppoe_init(void)
+{
+ int err;
+
+ err = register_pernet_device(&pppoe_net_ops);
+ if (err)
+ goto out;
+
+ err = proto_register(&pppoe_sk_proto, 0);
+ if (err)
+ goto out_unregister_net_ops;
+
+ err = register_pppox_proto(PX_PROTO_OE, &pppoe_proto);
+ if (err)
+ goto out_unregister_pppoe_proto;
+
+ dev_add_pack(&pppoes_ptype);
+ dev_add_pack(&pppoed_ptype);
+ register_netdevice_notifier(&pppoe_notifier);
+
+ return 0;
+
+out_unregister_pppoe_proto:
+ proto_unregister(&pppoe_sk_proto);
+out_unregister_net_ops:
+ unregister_pernet_device(&pppoe_net_ops);
+out:
+ return err;
+}
+
+static void __exit pppoe_exit(void)
+{
+ unregister_netdevice_notifier(&pppoe_notifier);
+ dev_remove_pack(&pppoed_ptype);
+ dev_remove_pack(&pppoes_ptype);
+ unregister_pppox_proto(PX_PROTO_OE);
+ proto_unregister(&pppoe_sk_proto);
+ unregister_pernet_device(&pppoe_net_ops);
+}
+
+module_init(pppoe_init);
+module_exit(pppoe_exit);
+
+MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
+MODULE_DESCRIPTION("PPP over Ethernet driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(PF_PPPOX);
Code Review / kvmfornfv.git / blobdiff