/*
|
* Generic PPP layer for Linux.
|
*
|
* Copyright 1999-2002 Paul Mackerras.
|
*
|
* 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.
|
*
|
* The generic PPP layer handles the PPP network interfaces, the
|
* /dev/ppp device, packet and VJ compression, and multilink.
|
* It talks to PPP `channels' via the interface defined in
|
* include/linux/ppp_channel.h. Channels provide the basic means for
|
* sending and receiving PPP frames on some kind of communications
|
* channel.
|
*
|
* Part of the code in this driver was inspired by the old async-only
|
* PPP driver, written by Michael Callahan and Al Longyear, and
|
* subsequently hacked by Paul Mackerras.
|
*
|
* ==FILEVERSION 20041108==
|
*/
|
|
#include <linux/module.h>
|
#include <linux/kernel.h>
|
#include <linux/sched/signal.h>
|
#include <linux/kmod.h>
|
#include <linux/init.h>
|
#include <linux/list.h>
|
#include <linux/idr.h>
|
#include <linux/netdevice.h>
|
#include <linux/poll.h>
|
#include <linux/ppp_defs.h>
|
#include <linux/filter.h>
|
#include <linux/ppp-ioctl.h>
|
#include <linux/ppp_channel.h>
|
#include <linux/ppp-comp.h>
|
#include <linux/skbuff.h>
|
#include <linux/rtnetlink.h>
|
#include <linux/if_arp.h>
|
#include <linux/ip.h>
|
#include <linux/tcp.h>
|
#include <linux/spinlock.h>
|
#include <linux/rwsem.h>
|
#include <linux/stddef.h>
|
#include <linux/device.h>
|
#include <linux/mutex.h>
|
#include <linux/slab.h>
|
#include <linux/file.h>
|
#include <asm/unaligned.h>
|
#include <net/slhc_vj.h>
|
#include <linux/atomic.h>
|
#include <linux/refcount.h>
|
|
#include <linux/nsproxy.h>
|
#include <net/net_namespace.h>
|
#include <net/netns/generic.h>
|
|
#define PPP_VERSION "2.4.2"
|
|
/*
|
* Network protocols we support.
|
*/
|
#define NP_IP 0 /* Internet Protocol V4 */
|
#define NP_IPV6 1 /* Internet Protocol V6 */
|
#define NP_IPX 2 /* IPX protocol */
|
#define NP_AT 3 /* Appletalk protocol */
|
#define NP_MPLS_UC 4 /* MPLS unicast */
|
#define NP_MPLS_MC 5 /* MPLS multicast */
|
#define NUM_NP 6 /* Number of NPs. */
|
|
#define MPHDRLEN 6 /* multilink protocol header length */
|
#define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */
|
|
#define PPP_PROTO_LEN 2
|
|
/*
|
* An instance of /dev/ppp can be associated with either a ppp
|
* interface unit or a ppp channel. In both cases, file->private_data
|
* points to one of these.
|
*/
|
struct ppp_file {
|
enum {
|
INTERFACE=1, CHANNEL
|
} kind;
|
struct sk_buff_head xq; /* pppd transmit queue */
|
struct sk_buff_head rq; /* receive queue for pppd */
|
wait_queue_head_t rwait; /* for poll on reading /dev/ppp */
|
refcount_t refcnt; /* # refs (incl /dev/ppp attached) */
|
int hdrlen; /* space to leave for headers */
|
int index; /* interface unit / channel number */
|
int dead; /* unit/channel has been shut down */
|
};
|
|
#define PF_TO_X(pf, X) container_of(pf, X, file)
|
|
#define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp)
|
#define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel)
|
|
/*
|
* Data structure to hold primary network stats for which
|
* we want to use 64 bit storage. Other network stats
|
* are stored in dev->stats of the ppp strucute.
|
*/
|
struct ppp_link_stats {
|
u64 rx_packets;
|
u64 tx_packets;
|
u64 rx_bytes;
|
u64 tx_bytes;
|
};
|
|
/*
|
* Data structure describing one ppp unit.
|
* A ppp unit corresponds to a ppp network interface device
|
* and represents a multilink bundle.
|
* It can have 0 or more ppp channels connected to it.
|
*/
|
struct ppp {
|
struct ppp_file file; /* stuff for read/write/poll 0 */
|
struct file *owner; /* file that owns this unit 48 */
|
struct list_head channels; /* list of attached channels 4c */
|
int n_channels; /* how many channels are attached 54 */
|
spinlock_t rlock; /* lock for receive side 58 */
|
spinlock_t wlock; /* lock for transmit side 5c */
|
int __percpu *xmit_recursion; /* xmit recursion detect */
|
int mru; /* max receive unit 60 */
|
unsigned int flags; /* control bits 64 */
|
unsigned int xstate; /* transmit state bits 68 */
|
unsigned int rstate; /* receive state bits 6c */
|
int debug; /* debug flags 70 */
|
struct slcompress *vj; /* state for VJ header compression */
|
enum NPmode npmode[NUM_NP]; /* what to do with each net proto 78 */
|
struct sk_buff *xmit_pending; /* a packet ready to go out 88 */
|
struct compressor *xcomp; /* transmit packet compressor 8c */
|
void *xc_state; /* its internal state 90 */
|
struct compressor *rcomp; /* receive decompressor 94 */
|
void *rc_state; /* its internal state 98 */
|
unsigned long last_xmit; /* jiffies when last pkt sent 9c */
|
unsigned long last_recv; /* jiffies when last pkt rcvd a0 */
|
struct net_device *dev; /* network interface device a4 */
|
int closing; /* is device closing down? a8 */
|
#ifdef CONFIG_PPP_MULTILINK
|
int nxchan; /* next channel to send something on */
|
u32 nxseq; /* next sequence number to send */
|
int mrru; /* MP: max reconst. receive unit */
|
u32 nextseq; /* MP: seq no of next packet */
|
u32 minseq; /* MP: min of most recent seqnos */
|
struct sk_buff_head mrq; /* MP: receive reconstruction queue */
|
#endif /* CONFIG_PPP_MULTILINK */
|
#ifdef CONFIG_PPP_FILTER
|
struct bpf_prog *pass_filter; /* filter for packets to pass */
|
struct bpf_prog *active_filter; /* filter for pkts to reset idle */
|
#endif /* CONFIG_PPP_FILTER */
|
struct net *ppp_net; /* the net we belong to */
|
struct ppp_link_stats stats64; /* 64 bit network stats */
|
};
|
|
/*
|
* Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
|
* SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP,
|
* SC_MUST_COMP
|
* Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR.
|
* Bits in xstate: SC_COMP_RUN
|
*/
|
#define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \
|
|SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \
|
|SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP)
|
|
/*
|
* Private data structure for each channel.
|
* This includes the data structure used for multilink.
|
*/
|
struct channel {
|
struct ppp_file file; /* stuff for read/write/poll */
|
struct list_head list; /* link in all/new_channels list */
|
struct ppp_channel *chan; /* public channel data structure */
|
struct rw_semaphore chan_sem; /* protects `chan' during chan ioctl */
|
spinlock_t downl; /* protects `chan', file.xq dequeue */
|
struct ppp *ppp; /* ppp unit we're connected to */
|
struct net *chan_net; /* the net channel belongs to */
|
struct list_head clist; /* link in list of channels per unit */
|
rwlock_t upl; /* protects `ppp' */
|
#ifdef CONFIG_PPP_MULTILINK
|
u8 avail; /* flag used in multilink stuff */
|
u8 had_frag; /* >= 1 fragments have been sent */
|
u32 lastseq; /* MP: last sequence # received */
|
int speed; /* speed of the corresponding ppp channel*/
|
#endif /* CONFIG_PPP_MULTILINK */
|
};
|
|
struct ppp_config {
|
struct file *file;
|
s32 unit;
|
bool ifname_is_set;
|
};
|
|
/*
|
* SMP locking issues:
|
* Both the ppp.rlock and ppp.wlock locks protect the ppp.channels
|
* list and the ppp.n_channels field, you need to take both locks
|
* before you modify them.
|
* The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
|
* channel.downl.
|
*/
|
|
static DEFINE_MUTEX(ppp_mutex);
|
static atomic_t ppp_unit_count = ATOMIC_INIT(0);
|
static atomic_t channel_count = ATOMIC_INIT(0);
|
|
/* per-net private data for this module */
|
static unsigned int ppp_net_id __read_mostly;
|
struct ppp_net {
|
/* units to ppp mapping */
|
struct idr units_idr;
|
|
/*
|
* all_ppp_mutex protects the units_idr mapping.
|
* It also ensures that finding a ppp unit in the units_idr
|
* map and updating its file.refcnt field is atomic.
|
*/
|
struct mutex all_ppp_mutex;
|
|
/* channels */
|
struct list_head all_channels;
|
struct list_head new_channels;
|
int last_channel_index;
|
|
/*
|
* all_channels_lock protects all_channels and
|
* last_channel_index, and the atomicity of find
|
* a channel and updating its file.refcnt field.
|
*/
|
spinlock_t all_channels_lock;
|
};
|
|
/* Get the PPP protocol number from a skb */
|
#define PPP_PROTO(skb) get_unaligned_be16((skb)->data)
|
|
/* We limit the length of ppp->file.rq to this (arbitrary) value */
|
#define PPP_MAX_RQLEN 32
|
|
/*
|
* Maximum number of multilink fragments queued up.
|
* This has to be large enough to cope with the maximum latency of
|
* the slowest channel relative to the others. Strictly it should
|
* depend on the number of channels and their characteristics.
|
*/
|
#define PPP_MP_MAX_QLEN 128
|
|
/* Multilink header bits. */
|
#define B 0x80 /* this fragment begins a packet */
|
#define E 0x40 /* this fragment ends a packet */
|
|
/* Compare multilink sequence numbers (assumed to be 32 bits wide) */
|
#define seq_before(a, b) ((s32)((a) - (b)) < 0)
|
#define seq_after(a, b) ((s32)((a) - (b)) > 0)
|
|
/* Prototypes. */
|
static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
|
struct file *file, unsigned int cmd, unsigned long arg);
|
static void ppp_xmit_process(struct ppp *ppp, struct sk_buff *skb);
|
static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb);
|
static void ppp_push(struct ppp *ppp);
|
static void ppp_channel_push(struct channel *pch);
|
static void ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb,
|
struct channel *pch);
|
static void ppp_receive_error(struct ppp *ppp);
|
static void ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb);
|
static struct sk_buff *ppp_decompress_frame(struct ppp *ppp,
|
struct sk_buff *skb);
|
#ifdef CONFIG_PPP_MULTILINK
|
static void ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb,
|
struct channel *pch);
|
static void ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb);
|
static struct sk_buff *ppp_mp_reconstruct(struct ppp *ppp);
|
static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb);
|
#endif /* CONFIG_PPP_MULTILINK */
|
static int ppp_set_compress(struct ppp *ppp, unsigned long arg);
|
static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound);
|
static void ppp_ccp_closed(struct ppp *ppp);
|
static struct compressor *find_compressor(int type);
|
static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st);
|
static int ppp_create_interface(struct net *net, struct file *file, int *unit);
|
static void init_ppp_file(struct ppp_file *pf, int kind);
|
static void ppp_destroy_interface(struct ppp *ppp);
|
static struct ppp *ppp_find_unit(struct ppp_net *pn, int unit);
|
static struct channel *ppp_find_channel(struct ppp_net *pn, int unit);
|
static int ppp_connect_channel(struct channel *pch, int unit);
|
static int ppp_disconnect_channel(struct channel *pch);
|
static void ppp_destroy_channel(struct channel *pch);
|
static int unit_get(struct idr *p, void *ptr, int min);
|
static int unit_set(struct idr *p, void *ptr, int n);
|
static void unit_put(struct idr *p, int n);
|
static void *unit_find(struct idr *p, int n);
|
static void ppp_setup(struct net_device *dev);
|
|
static const struct net_device_ops ppp_netdev_ops;
|
|
static struct class *ppp_class;
|
|
/* per net-namespace data */
|
static inline struct ppp_net *ppp_pernet(struct net *net)
|
{
|
BUG_ON(!net);
|
|
return net_generic(net, ppp_net_id);
|
}
|
|
/* Translates a PPP protocol number to a NP index (NP == network protocol) */
|
static inline int proto_to_npindex(int proto)
|
{
|
switch (proto) {
|
case PPP_IP:
|
return NP_IP;
|
case PPP_IPV6:
|
return NP_IPV6;
|
case PPP_IPX:
|
return NP_IPX;
|
case PPP_AT:
|
return NP_AT;
|
case PPP_MPLS_UC:
|
return NP_MPLS_UC;
|
case PPP_MPLS_MC:
|
return NP_MPLS_MC;
|
}
|
return -EINVAL;
|
}
|
|
/* Translates an NP index into a PPP protocol number */
|
static const int npindex_to_proto[NUM_NP] = {
|
PPP_IP,
|
PPP_IPV6,
|
PPP_IPX,
|
PPP_AT,
|
PPP_MPLS_UC,
|
PPP_MPLS_MC,
|
};
|
|
/* Translates an ethertype into an NP index */
|
static inline int ethertype_to_npindex(int ethertype)
|
{
|
switch (ethertype) {
|
case ETH_P_IP:
|
return NP_IP;
|
case ETH_P_IPV6:
|
return NP_IPV6;
|
case ETH_P_IPX:
|
return NP_IPX;
|
case ETH_P_PPPTALK:
|
case ETH_P_ATALK:
|
return NP_AT;
|
case ETH_P_MPLS_UC:
|
return NP_MPLS_UC;
|
case ETH_P_MPLS_MC:
|
return NP_MPLS_MC;
|
}
|
return -1;
|
}
|
|
/* Translates an NP index into an ethertype */
|
static const int npindex_to_ethertype[NUM_NP] = {
|
ETH_P_IP,
|
ETH_P_IPV6,
|
ETH_P_IPX,
|
ETH_P_PPPTALK,
|
ETH_P_MPLS_UC,
|
ETH_P_MPLS_MC,
|
};
|
|
/*
|
* Locking shorthand.
|
*/
|
#define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock)
|
#define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock)
|
#define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock)
|
#define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock)
|
#define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \
|
ppp_recv_lock(ppp); } while (0)
|
#define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \
|
ppp_xmit_unlock(ppp); } while (0)
|
|
/*
|
* /dev/ppp device routines.
|
* The /dev/ppp device is used by pppd to control the ppp unit.
|
* It supports the read, write, ioctl and poll functions.
|
* Open instances of /dev/ppp can be in one of three states:
|
* unattached, attached to a ppp unit, or attached to a ppp channel.
|
*/
|
static int ppp_open(struct inode *inode, struct file *file)
|
{
|
/*
|
* This could (should?) be enforced by the permissions on /dev/ppp.
|
*/
|
if (!ns_capable(file->f_cred->user_ns, CAP_NET_ADMIN))
|
return -EPERM;
|
return 0;
|
}
|
|
static int ppp_release(struct inode *unused, struct file *file)
|
{
|
struct ppp_file *pf = file->private_data;
|
struct ppp *ppp;
|
|
if (pf) {
|
file->private_data = NULL;
|
if (pf->kind == INTERFACE) {
|
ppp = PF_TO_PPP(pf);
|
rtnl_lock();
|
if (file == ppp->owner)
|
unregister_netdevice(ppp->dev);
|
rtnl_unlock();
|
}
|
if (refcount_dec_and_test(&pf->refcnt)) {
|
switch (pf->kind) {
|
case INTERFACE:
|
ppp_destroy_interface(PF_TO_PPP(pf));
|
break;
|
case CHANNEL:
|
ppp_destroy_channel(PF_TO_CHANNEL(pf));
|
break;
|
}
|
}
|
}
|
return 0;
|
}
|
|
static ssize_t ppp_read(struct file *file, char __user *buf,
|
size_t count, loff_t *ppos)
|
{
|
struct ppp_file *pf = file->private_data;
|
DECLARE_WAITQUEUE(wait, current);
|
ssize_t ret;
|
struct sk_buff *skb = NULL;
|
struct iovec iov;
|
struct iov_iter to;
|
|
ret = count;
|
|
if (!pf)
|
return -ENXIO;
|
add_wait_queue(&pf->rwait, &wait);
|
for (;;) {
|
set_current_state(TASK_INTERRUPTIBLE);
|
skb = skb_dequeue(&pf->rq);
|
if (skb)
|
break;
|
ret = 0;
|
if (pf->dead)
|
break;
|
if (pf->kind == INTERFACE) {
|
/*
|
* Return 0 (EOF) on an interface that has no
|
* channels connected, unless it is looping
|
* network traffic (demand mode).
|
*/
|
struct ppp *ppp = PF_TO_PPP(pf);
|
|
ppp_recv_lock(ppp);
|
if (ppp->n_channels == 0 &&
|
(ppp->flags & SC_LOOP_TRAFFIC) == 0) {
|
ppp_recv_unlock(ppp);
|
break;
|
}
|
ppp_recv_unlock(ppp);
|
}
|
ret = -EAGAIN;
|
if (file->f_flags & O_NONBLOCK)
|
break;
|
ret = -ERESTARTSYS;
|
if (signal_pending(current))
|
break;
|
schedule();
|
}
|
set_current_state(TASK_RUNNING);
|
remove_wait_queue(&pf->rwait, &wait);
|
|
if (!skb)
|
goto out;
|
|
ret = -EOVERFLOW;
|
if (skb->len > count)
|
goto outf;
|
ret = -EFAULT;
|
iov.iov_base = buf;
|
iov.iov_len = count;
|
iov_iter_init(&to, READ, &iov, 1, count);
|
if (skb_copy_datagram_iter(skb, 0, &to, skb->len))
|
goto outf;
|
ret = skb->len;
|
|
outf:
|
kfree_skb(skb);
|
out:
|
return ret;
|
}
|
|
static ssize_t ppp_write(struct file *file, const char __user *buf,
|
size_t count, loff_t *ppos)
|
{
|
struct ppp_file *pf = file->private_data;
|
struct sk_buff *skb;
|
ssize_t ret;
|
|
if (!pf)
|
return -ENXIO;
|
/* All PPP packets should start with the 2-byte protocol */
|
if (count < PPP_PROTO_LEN)
|
return -EINVAL;
|
ret = -ENOMEM;
|
skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL);
|
if (!skb)
|
goto out;
|
skb_reserve(skb, pf->hdrlen);
|
ret = -EFAULT;
|
if (copy_from_user(skb_put(skb, count), buf, count)) {
|
kfree_skb(skb);
|
goto out;
|
}
|
|
switch (pf->kind) {
|
case INTERFACE:
|
ppp_xmit_process(PF_TO_PPP(pf), skb);
|
break;
|
case CHANNEL:
|
skb_queue_tail(&pf->xq, skb);
|
ppp_channel_push(PF_TO_CHANNEL(pf));
|
break;
|
}
|
|
ret = count;
|
|
out:
|
return ret;
|
}
|
|
/* No kernel lock - fine */
|
static __poll_t ppp_poll(struct file *file, poll_table *wait)
|
{
|
struct ppp_file *pf = file->private_data;
|
__poll_t mask;
|
|
if (!pf)
|
return 0;
|
poll_wait(file, &pf->rwait, wait);
|
mask = EPOLLOUT | EPOLLWRNORM;
|
if (skb_peek(&pf->rq))
|
mask |= EPOLLIN | EPOLLRDNORM;
|
if (pf->dead)
|
mask |= EPOLLHUP;
|
else if (pf->kind == INTERFACE) {
|
/* see comment in ppp_read */
|
struct ppp *ppp = PF_TO_PPP(pf);
|
|
ppp_recv_lock(ppp);
|
if (ppp->n_channels == 0 &&
|
(ppp->flags & SC_LOOP_TRAFFIC) == 0)
|
mask |= EPOLLIN | EPOLLRDNORM;
|
ppp_recv_unlock(ppp);
|
}
|
|
return mask;
|
}
|
|
#ifdef CONFIG_PPP_FILTER
|
static int get_filter(void __user *arg, struct sock_filter **p)
|
{
|
struct sock_fprog uprog;
|
struct sock_filter *code = NULL;
|
int len;
|
|
if (copy_from_user(&uprog, arg, sizeof(uprog)))
|
return -EFAULT;
|
|
if (!uprog.len) {
|
*p = NULL;
|
return 0;
|
}
|
|
len = uprog.len * sizeof(struct sock_filter);
|
code = memdup_user(uprog.filter, len);
|
if (IS_ERR(code))
|
return PTR_ERR(code);
|
|
*p = code;
|
return uprog.len;
|
}
|
#endif /* CONFIG_PPP_FILTER */
|
|
static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
{
|
struct ppp_file *pf;
|
struct ppp *ppp;
|
int err = -EFAULT, val, val2, i;
|
struct ppp_idle idle;
|
struct npioctl npi;
|
int unit, cflags;
|
struct slcompress *vj;
|
void __user *argp = (void __user *)arg;
|
int __user *p = argp;
|
|
mutex_lock(&ppp_mutex);
|
|
pf = file->private_data;
|
if (!pf) {
|
err = ppp_unattached_ioctl(current->nsproxy->net_ns,
|
pf, file, cmd, arg);
|
goto out;
|
}
|
|
if (cmd == PPPIOCDETACH) {
|
/*
|
* PPPIOCDETACH is no longer supported as it was heavily broken,
|
* and is only known to have been used by pppd older than
|
* ppp-2.4.2 (released November 2003).
|
*/
|
pr_warn_once("%s (%d) used obsolete PPPIOCDETACH ioctl\n",
|
current->comm, current->pid);
|
err = -EINVAL;
|
goto out;
|
}
|
|
if (pf->kind == CHANNEL) {
|
struct channel *pch;
|
struct ppp_channel *chan;
|
|
pch = PF_TO_CHANNEL(pf);
|
|
switch (cmd) {
|
case PPPIOCCONNECT:
|
if (get_user(unit, p))
|
break;
|
err = ppp_connect_channel(pch, unit);
|
break;
|
|
case PPPIOCDISCONN:
|
err = ppp_disconnect_channel(pch);
|
break;
|
|
default:
|
down_read(&pch->chan_sem);
|
chan = pch->chan;
|
err = -ENOTTY;
|
if (chan && chan->ops->ioctl)
|
err = chan->ops->ioctl(chan, cmd, arg);
|
up_read(&pch->chan_sem);
|
}
|
goto out;
|
}
|
|
if (pf->kind != INTERFACE) {
|
/* can't happen */
|
pr_err("PPP: not interface or channel??\n");
|
err = -EINVAL;
|
goto out;
|
}
|
|
ppp = PF_TO_PPP(pf);
|
switch (cmd) {
|
case PPPIOCSMRU:
|
if (get_user(val, p))
|
break;
|
ppp->mru = val;
|
err = 0;
|
break;
|
|
case PPPIOCSFLAGS:
|
if (get_user(val, p))
|
break;
|
ppp_lock(ppp);
|
cflags = ppp->flags & ~val;
|
#ifdef CONFIG_PPP_MULTILINK
|
if (!(ppp->flags & SC_MULTILINK) && (val & SC_MULTILINK))
|
ppp->nextseq = 0;
|
#endif
|
ppp->flags = val & SC_FLAG_BITS;
|
ppp_unlock(ppp);
|
if (cflags & SC_CCP_OPEN)
|
ppp_ccp_closed(ppp);
|
err = 0;
|
break;
|
|
case PPPIOCGFLAGS:
|
val = ppp->flags | ppp->xstate | ppp->rstate;
|
if (put_user(val, p))
|
break;
|
err = 0;
|
break;
|
|
case PPPIOCSCOMPRESS:
|
err = ppp_set_compress(ppp, arg);
|
break;
|
|
case PPPIOCGUNIT:
|
if (put_user(ppp->file.index, p))
|
break;
|
err = 0;
|
break;
|
|
case PPPIOCSDEBUG:
|
if (get_user(val, p))
|
break;
|
ppp->debug = val;
|
err = 0;
|
break;
|
|
case PPPIOCGDEBUG:
|
if (put_user(ppp->debug, p))
|
break;
|
err = 0;
|
break;
|
|
case PPPIOCGIDLE:
|
idle.xmit_idle = (jiffies - ppp->last_xmit) / HZ;
|
idle.recv_idle = (jiffies - ppp->last_recv) / HZ;
|
if (copy_to_user(argp, &idle, sizeof(idle)))
|
break;
|
err = 0;
|
break;
|
|
case PPPIOCSMAXCID:
|
if (get_user(val, p))
|
break;
|
val2 = 15;
|
if ((val >> 16) != 0) {
|
val2 = val >> 16;
|
val &= 0xffff;
|
}
|
vj = slhc_init(val2+1, val+1);
|
if (IS_ERR(vj)) {
|
err = PTR_ERR(vj);
|
break;
|
}
|
ppp_lock(ppp);
|
if (ppp->vj)
|
slhc_free(ppp->vj);
|
ppp->vj = vj;
|
ppp_unlock(ppp);
|
err = 0;
|
break;
|
|
case PPPIOCGNPMODE:
|
case PPPIOCSNPMODE:
|
if (copy_from_user(&npi, argp, sizeof(npi)))
|
break;
|
err = proto_to_npindex(npi.protocol);
|
if (err < 0)
|
break;
|
i = err;
|
if (cmd == PPPIOCGNPMODE) {
|
err = -EFAULT;
|
npi.mode = ppp->npmode[i];
|
if (copy_to_user(argp, &npi, sizeof(npi)))
|
break;
|
} else {
|
ppp->npmode[i] = npi.mode;
|
/* we may be able to transmit more packets now (??) */
|
netif_wake_queue(ppp->dev);
|
}
|
err = 0;
|
break;
|
|
#ifdef CONFIG_PPP_FILTER
|
case PPPIOCSPASS:
|
{
|
struct sock_filter *code;
|
|
err = get_filter(argp, &code);
|
if (err >= 0) {
|
struct bpf_prog *pass_filter = NULL;
|
struct sock_fprog_kern fprog = {
|
.len = err,
|
.filter = code,
|
};
|
|
err = 0;
|
if (fprog.filter)
|
err = bpf_prog_create(&pass_filter, &fprog);
|
if (!err) {
|
ppp_lock(ppp);
|
if (ppp->pass_filter)
|
bpf_prog_destroy(ppp->pass_filter);
|
ppp->pass_filter = pass_filter;
|
ppp_unlock(ppp);
|
}
|
kfree(code);
|
}
|
break;
|
}
|
case PPPIOCSACTIVE:
|
{
|
struct sock_filter *code;
|
|
err = get_filter(argp, &code);
|
if (err >= 0) {
|
struct bpf_prog *active_filter = NULL;
|
struct sock_fprog_kern fprog = {
|
.len = err,
|
.filter = code,
|
};
|
|
err = 0;
|
if (fprog.filter)
|
err = bpf_prog_create(&active_filter, &fprog);
|
if (!err) {
|
ppp_lock(ppp);
|
if (ppp->active_filter)
|
bpf_prog_destroy(ppp->active_filter);
|
ppp->active_filter = active_filter;
|
ppp_unlock(ppp);
|
}
|
kfree(code);
|
}
|
break;
|
}
|
#endif /* CONFIG_PPP_FILTER */
|
|
#ifdef CONFIG_PPP_MULTILINK
|
case PPPIOCSMRRU:
|
if (get_user(val, p))
|
break;
|
ppp_recv_lock(ppp);
|
ppp->mrru = val;
|
ppp_recv_unlock(ppp);
|
err = 0;
|
break;
|
#endif /* CONFIG_PPP_MULTILINK */
|
|
default:
|
err = -ENOTTY;
|
}
|
|
out:
|
mutex_unlock(&ppp_mutex);
|
|
return err;
|
}
|
|
static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
|
struct file *file, unsigned int cmd, unsigned long arg)
|
{
|
int unit, err = -EFAULT;
|
struct ppp *ppp;
|
struct channel *chan;
|
struct ppp_net *pn;
|
int __user *p = (int __user *)arg;
|
|
switch (cmd) {
|
case PPPIOCNEWUNIT:
|
/* Create a new ppp unit */
|
if (get_user(unit, p))
|
break;
|
err = ppp_create_interface(net, file, &unit);
|
if (err < 0)
|
break;
|
|
err = -EFAULT;
|
if (put_user(unit, p))
|
break;
|
err = 0;
|
break;
|
|
case PPPIOCATTACH:
|
/* Attach to an existing ppp unit */
|
if (get_user(unit, p))
|
break;
|
err = -ENXIO;
|
pn = ppp_pernet(net);
|
mutex_lock(&pn->all_ppp_mutex);
|
ppp = ppp_find_unit(pn, unit);
|
if (ppp) {
|
refcount_inc(&ppp->file.refcnt);
|
file->private_data = &ppp->file;
|
err = 0;
|
}
|
mutex_unlock(&pn->all_ppp_mutex);
|
break;
|
|
case PPPIOCATTCHAN:
|
if (get_user(unit, p))
|
break;
|
err = -ENXIO;
|
pn = ppp_pernet(net);
|
spin_lock_bh(&pn->all_channels_lock);
|
chan = ppp_find_channel(pn, unit);
|
if (chan) {
|
refcount_inc(&chan->file.refcnt);
|
file->private_data = &chan->file;
|
err = 0;
|
}
|
spin_unlock_bh(&pn->all_channels_lock);
|
break;
|
|
default:
|
err = -ENOTTY;
|
}
|
|
return err;
|
}
|
|
static const struct file_operations ppp_device_fops = {
|
.owner = THIS_MODULE,
|
.read = ppp_read,
|
.write = ppp_write,
|
.poll = ppp_poll,
|
.unlocked_ioctl = ppp_ioctl,
|
.open = ppp_open,
|
.release = ppp_release,
|
.llseek = noop_llseek,
|
};
|
|
static __net_init int ppp_init_net(struct net *net)
|
{
|
struct ppp_net *pn = net_generic(net, ppp_net_id);
|
|
idr_init(&pn->units_idr);
|
mutex_init(&pn->all_ppp_mutex);
|
|
INIT_LIST_HEAD(&pn->all_channels);
|
INIT_LIST_HEAD(&pn->new_channels);
|
|
spin_lock_init(&pn->all_channels_lock);
|
|
return 0;
|
}
|
|
static __net_exit void ppp_exit_net(struct net *net)
|
{
|
struct ppp_net *pn = net_generic(net, ppp_net_id);
|
struct net_device *dev;
|
struct net_device *aux;
|
struct ppp *ppp;
|
LIST_HEAD(list);
|
int id;
|
|
rtnl_lock();
|
for_each_netdev_safe(net, dev, aux) {
|
if (dev->netdev_ops == &ppp_netdev_ops)
|
unregister_netdevice_queue(dev, &list);
|
}
|
|
idr_for_each_entry(&pn->units_idr, ppp, id)
|
/* Skip devices already unregistered by previous loop */
|
if (!net_eq(dev_net(ppp->dev), net))
|
unregister_netdevice_queue(ppp->dev, &list);
|
|
unregister_netdevice_many(&list);
|
rtnl_unlock();
|
|
mutex_destroy(&pn->all_ppp_mutex);
|
idr_destroy(&pn->units_idr);
|
WARN_ON_ONCE(!list_empty(&pn->all_channels));
|
WARN_ON_ONCE(!list_empty(&pn->new_channels));
|
}
|
|
static struct pernet_operations ppp_net_ops = {
|
.init = ppp_init_net,
|
.exit = ppp_exit_net,
|
.id = &ppp_net_id,
|
.size = sizeof(struct ppp_net),
|
};
|
|
static int ppp_unit_register(struct ppp *ppp, int unit, bool ifname_is_set)
|
{
|
struct ppp_net *pn = ppp_pernet(ppp->ppp_net);
|
int ret;
|
|
mutex_lock(&pn->all_ppp_mutex);
|
|
if (unit < 0) {
|
ret = unit_get(&pn->units_idr, ppp, 0);
|
if (ret < 0)
|
goto err;
|
if (!ifname_is_set) {
|
while (1) {
|
snprintf(ppp->dev->name, IFNAMSIZ, "ppp%i", ret);
|
if (!__dev_get_by_name(ppp->ppp_net, ppp->dev->name))
|
break;
|
unit_put(&pn->units_idr, ret);
|
ret = unit_get(&pn->units_idr, ppp, ret + 1);
|
if (ret < 0)
|
goto err;
|
}
|
}
|
} else {
|
/* Caller asked for a specific unit number. Fail with -EEXIST
|
* if unavailable. For backward compatibility, return -EEXIST
|
* too if idr allocation fails; this makes pppd retry without
|
* requesting a specific unit number.
|
*/
|
if (unit_find(&pn->units_idr, unit)) {
|
ret = -EEXIST;
|
goto err;
|
}
|
ret = unit_set(&pn->units_idr, ppp, unit);
|
if (ret < 0) {
|
/* Rewrite error for backward compatibility */
|
ret = -EEXIST;
|
goto err;
|
}
|
}
|
ppp->file.index = ret;
|
|
if (!ifname_is_set)
|
snprintf(ppp->dev->name, IFNAMSIZ, "ppp%i", ppp->file.index);
|
|
mutex_unlock(&pn->all_ppp_mutex);
|
|
ret = register_netdevice(ppp->dev);
|
if (ret < 0)
|
goto err_unit;
|
|
atomic_inc(&ppp_unit_count);
|
|
return 0;
|
|
err_unit:
|
mutex_lock(&pn->all_ppp_mutex);
|
unit_put(&pn->units_idr, ppp->file.index);
|
err:
|
mutex_unlock(&pn->all_ppp_mutex);
|
|
return ret;
|
}
|
|
static int ppp_dev_configure(struct net *src_net, struct net_device *dev,
|
const struct ppp_config *conf)
|
{
|
struct ppp *ppp = netdev_priv(dev);
|
int indx;
|
int err;
|
int cpu;
|
|
ppp->dev = dev;
|
ppp->ppp_net = src_net;
|
ppp->mru = PPP_MRU;
|
ppp->owner = conf->file;
|
|
init_ppp_file(&ppp->file, INTERFACE);
|
ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */
|
|
for (indx = 0; indx < NUM_NP; ++indx)
|
ppp->npmode[indx] = NPMODE_PASS;
|
INIT_LIST_HEAD(&ppp->channels);
|
spin_lock_init(&ppp->rlock);
|
spin_lock_init(&ppp->wlock);
|
|
ppp->xmit_recursion = alloc_percpu(int);
|
if (!ppp->xmit_recursion) {
|
err = -ENOMEM;
|
goto err1;
|
}
|
for_each_possible_cpu(cpu)
|
(*per_cpu_ptr(ppp->xmit_recursion, cpu)) = 0;
|
|
#ifdef CONFIG_PPP_MULTILINK
|
ppp->minseq = -1;
|
skb_queue_head_init(&ppp->mrq);
|
#endif /* CONFIG_PPP_MULTILINK */
|
#ifdef CONFIG_PPP_FILTER
|
ppp->pass_filter = NULL;
|
ppp->active_filter = NULL;
|
#endif /* CONFIG_PPP_FILTER */
|
|
err = ppp_unit_register(ppp, conf->unit, conf->ifname_is_set);
|
if (err < 0)
|
goto err2;
|
|
conf->file->private_data = &ppp->file;
|
|
return 0;
|
err2:
|
free_percpu(ppp->xmit_recursion);
|
err1:
|
return err;
|
}
|
|
static const struct nla_policy ppp_nl_policy[IFLA_PPP_MAX + 1] = {
|
[IFLA_PPP_DEV_FD] = { .type = NLA_S32 },
|
};
|
|
static int ppp_nl_validate(struct nlattr *tb[], struct nlattr *data[],
|
struct netlink_ext_ack *extack)
|
{
|
if (!data)
|
return -EINVAL;
|
|
if (!data[IFLA_PPP_DEV_FD])
|
return -EINVAL;
|
if (nla_get_s32(data[IFLA_PPP_DEV_FD]) < 0)
|
return -EBADF;
|
|
return 0;
|
}
|
|
static int ppp_nl_newlink(struct net *src_net, struct net_device *dev,
|
struct nlattr *tb[], struct nlattr *data[],
|
struct netlink_ext_ack *extack)
|
{
|
struct ppp_config conf = {
|
.unit = -1,
|
.ifname_is_set = true,
|
};
|
struct file *file;
|
int err;
|
|
file = fget(nla_get_s32(data[IFLA_PPP_DEV_FD]));
|
if (!file)
|
return -EBADF;
|
|
/* rtnl_lock is already held here, but ppp_create_interface() locks
|
* ppp_mutex before holding rtnl_lock. Using mutex_trylock() avoids
|
* possible deadlock due to lock order inversion, at the cost of
|
* pushing the problem back to userspace.
|
*/
|
if (!mutex_trylock(&ppp_mutex)) {
|
err = -EBUSY;
|
goto out;
|
}
|
|
if (file->f_op != &ppp_device_fops || file->private_data) {
|
err = -EBADF;
|
goto out_unlock;
|
}
|
|
conf.file = file;
|
|
/* Don't use device name generated by the rtnetlink layer when ifname
|
* isn't specified. Let ppp_dev_configure() set the device name using
|
* the PPP unit identifer as suffix (i.e. ppp<unit_id>). This allows
|
* userspace to infer the device name using to the PPPIOCGUNIT ioctl.
|
*/
|
if (!tb[IFLA_IFNAME] || !nla_len(tb[IFLA_IFNAME]) || !*(char *)nla_data(tb[IFLA_IFNAME]))
|
conf.ifname_is_set = false;
|
|
err = ppp_dev_configure(src_net, dev, &conf);
|
|
out_unlock:
|
mutex_unlock(&ppp_mutex);
|
out:
|
fput(file);
|
|
return err;
|
}
|
|
static void ppp_nl_dellink(struct net_device *dev, struct list_head *head)
|
{
|
unregister_netdevice_queue(dev, head);
|
}
|
|
static size_t ppp_nl_get_size(const struct net_device *dev)
|
{
|
return 0;
|
}
|
|
static int ppp_nl_fill_info(struct sk_buff *skb, const struct net_device *dev)
|
{
|
return 0;
|
}
|
|
static struct net *ppp_nl_get_link_net(const struct net_device *dev)
|
{
|
struct ppp *ppp = netdev_priv(dev);
|
|
return ppp->ppp_net;
|
}
|
|
static struct rtnl_link_ops ppp_link_ops __read_mostly = {
|
.kind = "ppp",
|
.maxtype = IFLA_PPP_MAX,
|
.policy = ppp_nl_policy,
|
.priv_size = sizeof(struct ppp),
|
.setup = ppp_setup,
|
.validate = ppp_nl_validate,
|
.newlink = ppp_nl_newlink,
|
.dellink = ppp_nl_dellink,
|
.get_size = ppp_nl_get_size,
|
.fill_info = ppp_nl_fill_info,
|
.get_link_net = ppp_nl_get_link_net,
|
};
|
|
#define PPP_MAJOR 108
|
|
/* Called at boot time if ppp is compiled into the kernel,
|
or at module load time (from init_module) if compiled as a module. */
|
static int __init ppp_init(void)
|
{
|
int err;
|
|
pr_info("PPP generic driver version " PPP_VERSION "\n");
|
|
err = register_pernet_device(&ppp_net_ops);
|
if (err) {
|
pr_err("failed to register PPP pernet device (%d)\n", err);
|
goto out;
|
}
|
|
err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops);
|
if (err) {
|
pr_err("failed to register PPP device (%d)\n", err);
|
goto out_net;
|
}
|
|
ppp_class = class_create(THIS_MODULE, "ppp");
|
if (IS_ERR(ppp_class)) {
|
err = PTR_ERR(ppp_class);
|
goto out_chrdev;
|
}
|
|
err = rtnl_link_register(&ppp_link_ops);
|
if (err) {
|
pr_err("failed to register rtnetlink PPP handler\n");
|
goto out_class;
|
}
|
|
/* not a big deal if we fail here :-) */
|
device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, "ppp");
|
|
return 0;
|
|
out_class:
|
class_destroy(ppp_class);
|
out_chrdev:
|
unregister_chrdev(PPP_MAJOR, "ppp");
|
out_net:
|
unregister_pernet_device(&ppp_net_ops);
|
out:
|
return err;
|
}
|
|
/*
|
* Network interface unit routines.
|
*/
|
static netdev_tx_t
|
ppp_start_xmit(struct sk_buff *skb, struct net_device *dev)
|
{
|
struct ppp *ppp = netdev_priv(dev);
|
int npi, proto;
|
unsigned char *pp;
|
|
npi = ethertype_to_npindex(ntohs(skb->protocol));
|
if (npi < 0)
|
goto outf;
|
|
/* Drop, accept or reject the packet */
|
switch (ppp->npmode[npi]) {
|
case NPMODE_PASS:
|
break;
|
case NPMODE_QUEUE:
|
/* it would be nice to have a way to tell the network
|
system to queue this one up for later. */
|
goto outf;
|
case NPMODE_DROP:
|
case NPMODE_ERROR:
|
goto outf;
|
}
|
|
/* Put the 2-byte PPP protocol number on the front,
|
making sure there is room for the address and control fields. */
|
if (skb_cow_head(skb, PPP_HDRLEN))
|
goto outf;
|
|
pp = skb_push(skb, 2);
|
proto = npindex_to_proto[npi];
|
put_unaligned_be16(proto, pp);
|
|
skb_scrub_packet(skb, !net_eq(ppp->ppp_net, dev_net(dev)));
|
ppp_xmit_process(ppp, skb);
|
|
return NETDEV_TX_OK;
|
|
outf:
|
kfree_skb(skb);
|
++dev->stats.tx_dropped;
|
return NETDEV_TX_OK;
|
}
|
|
static int
|
ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
|
{
|
struct ppp *ppp = netdev_priv(dev);
|
int err = -EFAULT;
|
void __user *addr = (void __user *) ifr->ifr_ifru.ifru_data;
|
struct ppp_stats stats;
|
struct ppp_comp_stats cstats;
|
char *vers;
|
|
switch (cmd) {
|
case SIOCGPPPSTATS:
|
ppp_get_stats(ppp, &stats);
|
if (copy_to_user(addr, &stats, sizeof(stats)))
|
break;
|
err = 0;
|
break;
|
|
case SIOCGPPPCSTATS:
|
memset(&cstats, 0, sizeof(cstats));
|
if (ppp->xc_state)
|
ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c);
|
if (ppp->rc_state)
|
ppp->rcomp->decomp_stat(ppp->rc_state, &cstats.d);
|
if (copy_to_user(addr, &cstats, sizeof(cstats)))
|
break;
|
err = 0;
|
break;
|
|
case SIOCGPPPVER:
|
vers = PPP_VERSION;
|
if (copy_to_user(addr, vers, strlen(vers) + 1))
|
break;
|
err = 0;
|
break;
|
|
default:
|
err = -EINVAL;
|
}
|
|
return err;
|
}
|
|
static void
|
ppp_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats64)
|
{
|
struct ppp *ppp = netdev_priv(dev);
|
|
ppp_recv_lock(ppp);
|
stats64->rx_packets = ppp->stats64.rx_packets;
|
stats64->rx_bytes = ppp->stats64.rx_bytes;
|
ppp_recv_unlock(ppp);
|
|
ppp_xmit_lock(ppp);
|
stats64->tx_packets = ppp->stats64.tx_packets;
|
stats64->tx_bytes = ppp->stats64.tx_bytes;
|
ppp_xmit_unlock(ppp);
|
|
stats64->rx_errors = dev->stats.rx_errors;
|
stats64->tx_errors = dev->stats.tx_errors;
|
stats64->rx_dropped = dev->stats.rx_dropped;
|
stats64->tx_dropped = dev->stats.tx_dropped;
|
stats64->rx_length_errors = dev->stats.rx_length_errors;
|
}
|
|
static int ppp_dev_init(struct net_device *dev)
|
{
|
struct ppp *ppp;
|
|
netdev_lockdep_set_classes(dev);
|
|
ppp = netdev_priv(dev);
|
/* Let the netdevice take a reference on the ppp file. This ensures
|
* that ppp_destroy_interface() won't run before the device gets
|
* unregistered.
|
*/
|
refcount_inc(&ppp->file.refcnt);
|
|
return 0;
|
}
|
|
static void ppp_dev_uninit(struct net_device *dev)
|
{
|
struct ppp *ppp = netdev_priv(dev);
|
struct ppp_net *pn = ppp_pernet(ppp->ppp_net);
|
|
ppp_lock(ppp);
|
ppp->closing = 1;
|
ppp_unlock(ppp);
|
|
mutex_lock(&pn->all_ppp_mutex);
|
unit_put(&pn->units_idr, ppp->file.index);
|
mutex_unlock(&pn->all_ppp_mutex);
|
|
ppp->owner = NULL;
|
|
ppp->file.dead = 1;
|
wake_up_interruptible(&ppp->file.rwait);
|
}
|
|
static void ppp_dev_priv_destructor(struct net_device *dev)
|
{
|
struct ppp *ppp;
|
|
ppp = netdev_priv(dev);
|
if (refcount_dec_and_test(&ppp->file.refcnt))
|
ppp_destroy_interface(ppp);
|
}
|
|
static const struct net_device_ops ppp_netdev_ops = {
|
.ndo_init = ppp_dev_init,
|
.ndo_uninit = ppp_dev_uninit,
|
.ndo_start_xmit = ppp_start_xmit,
|
.ndo_do_ioctl = ppp_net_ioctl,
|
.ndo_get_stats64 = ppp_get_stats64,
|
};
|
|
static struct device_type ppp_type = {
|
.name = "ppp",
|
};
|
|
static void ppp_setup(struct net_device *dev)
|
{
|
dev->netdev_ops = &ppp_netdev_ops;
|
SET_NETDEV_DEVTYPE(dev, &ppp_type);
|
|
dev->features |= NETIF_F_LLTX;
|
|
dev->hard_header_len = PPP_HDRLEN;
|
dev->mtu = PPP_MRU;
|
dev->addr_len = 0;
|
dev->tx_queue_len = 3;
|
dev->type = ARPHRD_PPP;
|
dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
|
dev->priv_destructor = ppp_dev_priv_destructor;
|
netif_keep_dst(dev);
|
}
|
|
/*
|
* Transmit-side routines.
|
*/
|
|
/* Called to do any work queued up on the transmit side that can now be done */
|
static void __ppp_xmit_process(struct ppp *ppp, struct sk_buff *skb)
|
{
|
ppp_xmit_lock(ppp);
|
if (!ppp->closing) {
|
ppp_push(ppp);
|
|
if (skb)
|
skb_queue_tail(&ppp->file.xq, skb);
|
while (!ppp->xmit_pending &&
|
(skb = skb_dequeue(&ppp->file.xq)))
|
ppp_send_frame(ppp, skb);
|
/* If there's no work left to do, tell the core net
|
code that we can accept some more. */
|
if (!ppp->xmit_pending && !skb_peek(&ppp->file.xq))
|
netif_wake_queue(ppp->dev);
|
else
|
netif_stop_queue(ppp->dev);
|
} else {
|
kfree_skb(skb);
|
}
|
ppp_xmit_unlock(ppp);
|
}
|
|
static void ppp_xmit_process(struct ppp *ppp, struct sk_buff *skb)
|
{
|
local_bh_disable();
|
|
if (unlikely(*this_cpu_ptr(ppp->xmit_recursion)))
|
goto err;
|
|
(*this_cpu_ptr(ppp->xmit_recursion))++;
|
__ppp_xmit_process(ppp, skb);
|
(*this_cpu_ptr(ppp->xmit_recursion))--;
|
|
local_bh_enable();
|
|
return;
|
|
err:
|
local_bh_enable();
|
|
kfree_skb(skb);
|
|
if (net_ratelimit())
|
netdev_err(ppp->dev, "recursion detected\n");
|
}
|
|
static inline struct sk_buff *
|
pad_compress_skb(struct ppp *ppp, struct sk_buff *skb)
|
{
|
struct sk_buff *new_skb;
|
int len;
|
int new_skb_size = ppp->dev->mtu +
|
ppp->xcomp->comp_extra + ppp->dev->hard_header_len;
|
int compressor_skb_size = ppp->dev->mtu +
|
ppp->xcomp->comp_extra + PPP_HDRLEN;
|
new_skb = alloc_skb(new_skb_size, GFP_ATOMIC);
|
if (!new_skb) {
|
if (net_ratelimit())
|
netdev_err(ppp->dev, "PPP: no memory (comp pkt)\n");
|
return NULL;
|
}
|
if (ppp->dev->hard_header_len > PPP_HDRLEN)
|
skb_reserve(new_skb,
|
ppp->dev->hard_header_len - PPP_HDRLEN);
|
|
/* compressor still expects A/C bytes in hdr */
|
len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2,
|
new_skb->data, skb->len + 2,
|
compressor_skb_size);
|
if (len > 0 && (ppp->flags & SC_CCP_UP)) {
|
consume_skb(skb);
|
skb = new_skb;
|
skb_put(skb, len);
|
skb_pull(skb, 2); /* pull off A/C bytes */
|
} else if (len == 0) {
|
/* didn't compress, or CCP not up yet */
|
consume_skb(new_skb);
|
new_skb = skb;
|
} else {
|
/*
|
* (len < 0)
|
* MPPE requires that we do not send unencrypted
|
* frames. The compressor will return -1 if we
|
* should drop the frame. We cannot simply test
|
* the compress_proto because MPPE and MPPC share
|
* the same number.
|
*/
|
if (net_ratelimit())
|
netdev_err(ppp->dev, "ppp: compressor dropped pkt\n");
|
kfree_skb(skb);
|
consume_skb(new_skb);
|
new_skb = NULL;
|
}
|
return new_skb;
|
}
|
|
/*
|
* Compress and send a frame.
|
* The caller should have locked the xmit path,
|
* and xmit_pending should be 0.
|
*/
|
static void
|
ppp_send_frame(struct ppp *ppp, struct sk_buff *skb)
|
{
|
int proto = PPP_PROTO(skb);
|
struct sk_buff *new_skb;
|
int len;
|
unsigned char *cp;
|
|
if (proto < 0x8000) {
|
#ifdef CONFIG_PPP_FILTER
|
/* check if we should pass this packet */
|
/* the filter instructions are constructed assuming
|
a four-byte PPP header on each packet */
|
*(u8 *)skb_push(skb, 2) = 1;
|
if (ppp->pass_filter &&
|
BPF_PROG_RUN(ppp->pass_filter, skb) == 0) {
|
if (ppp->debug & 1)
|
netdev_printk(KERN_DEBUG, ppp->dev,
|
"PPP: outbound frame "
|
"not passed\n");
|
kfree_skb(skb);
|
return;
|
}
|
/* if this packet passes the active filter, record the time */
|
if (!(ppp->active_filter &&
|
BPF_PROG_RUN(ppp->active_filter, skb) == 0))
|
ppp->last_xmit = jiffies;
|
skb_pull(skb, 2);
|
#else
|
/* for data packets, record the time */
|
ppp->last_xmit = jiffies;
|
#endif /* CONFIG_PPP_FILTER */
|
}
|
|
++ppp->stats64.tx_packets;
|
ppp->stats64.tx_bytes += skb->len - PPP_PROTO_LEN;
|
|
switch (proto) {
|
case PPP_IP:
|
if (!ppp->vj || (ppp->flags & SC_COMP_TCP) == 0)
|
break;
|
/* try to do VJ TCP header compression */
|
new_skb = alloc_skb(skb->len + ppp->dev->hard_header_len - 2,
|
GFP_ATOMIC);
|
if (!new_skb) {
|
netdev_err(ppp->dev, "PPP: no memory (VJ comp pkt)\n");
|
goto drop;
|
}
|
skb_reserve(new_skb, ppp->dev->hard_header_len - 2);
|
cp = skb->data + 2;
|
len = slhc_compress(ppp->vj, cp, skb->len - 2,
|
new_skb->data + 2, &cp,
|
!(ppp->flags & SC_NO_TCP_CCID));
|
if (cp == skb->data + 2) {
|
/* didn't compress */
|
consume_skb(new_skb);
|
} else {
|
if (cp[0] & SL_TYPE_COMPRESSED_TCP) {
|
proto = PPP_VJC_COMP;
|
cp[0] &= ~SL_TYPE_COMPRESSED_TCP;
|
} else {
|
proto = PPP_VJC_UNCOMP;
|
cp[0] = skb->data[2];
|
}
|
consume_skb(skb);
|
skb = new_skb;
|
cp = skb_put(skb, len + 2);
|
cp[0] = 0;
|
cp[1] = proto;
|
}
|
break;
|
|
case PPP_CCP:
|
/* peek at outbound CCP frames */
|
ppp_ccp_peek(ppp, skb, 0);
|
break;
|
}
|
|
/* try to do packet compression */
|
if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state &&
|
proto != PPP_LCP && proto != PPP_CCP) {
|
if (!(ppp->flags & SC_CCP_UP) && (ppp->flags & SC_MUST_COMP)) {
|
if (net_ratelimit())
|
netdev_err(ppp->dev,
|
"ppp: compression required but "
|
"down - pkt dropped.\n");
|
goto drop;
|
}
|
skb = pad_compress_skb(ppp, skb);
|
if (!skb)
|
goto drop;
|
}
|
|
/*
|
* If we are waiting for traffic (demand dialling),
|
* queue it up for pppd to receive.
|
*/
|
if (ppp->flags & SC_LOOP_TRAFFIC) {
|
if (ppp->file.rq.qlen > PPP_MAX_RQLEN)
|
goto drop;
|
skb_queue_tail(&ppp->file.rq, skb);
|
wake_up_interruptible(&ppp->file.rwait);
|
return;
|
}
|
|
ppp->xmit_pending = skb;
|
ppp_push(ppp);
|
return;
|
|
drop:
|
kfree_skb(skb);
|
++ppp->dev->stats.tx_errors;
|
}
|
|
/*
|
* Try to send the frame in xmit_pending.
|
* The caller should have the xmit path locked.
|
*/
|
static void
|
ppp_push(struct ppp *ppp)
|
{
|
struct list_head *list;
|
struct channel *pch;
|
struct sk_buff *skb = ppp->xmit_pending;
|
|
if (!skb)
|
return;
|
|
list = &ppp->channels;
|
if (list_empty(list)) {
|
/* nowhere to send the packet, just drop it */
|
ppp->xmit_pending = NULL;
|
kfree_skb(skb);
|
return;
|
}
|
|
if ((ppp->flags & SC_MULTILINK) == 0) {
|
/* not doing multilink: send it down the first channel */
|
list = list->next;
|
pch = list_entry(list, struct channel, clist);
|
|
spin_lock(&pch->downl);
|
if (pch->chan) {
|
if (pch->chan->ops->start_xmit(pch->chan, skb))
|
ppp->xmit_pending = NULL;
|
} else {
|
/* channel got unregistered */
|
kfree_skb(skb);
|
ppp->xmit_pending = NULL;
|
}
|
spin_unlock(&pch->downl);
|
return;
|
}
|
|
#ifdef CONFIG_PPP_MULTILINK
|
/* Multilink: fragment the packet over as many links
|
as can take the packet at the moment. */
|
if (!ppp_mp_explode(ppp, skb))
|
return;
|
#endif /* CONFIG_PPP_MULTILINK */
|
|
ppp->xmit_pending = NULL;
|
kfree_skb(skb);
|
}
|
|
#ifdef CONFIG_PPP_MULTILINK
|
static bool mp_protocol_compress __read_mostly = true;
|
module_param(mp_protocol_compress, bool, 0644);
|
MODULE_PARM_DESC(mp_protocol_compress,
|
"compress protocol id in multilink fragments");
|
|
/*
|
* Divide a packet to be transmitted into fragments and
|
* send them out the individual links.
|
*/
|
static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb)
|
{
|
int len, totlen;
|
int i, bits, hdrlen, mtu;
|
int flen;
|
int navail, nfree, nzero;
|
int nbigger;
|
int totspeed;
|
int totfree;
|
unsigned char *p, *q;
|
struct list_head *list;
|
struct channel *pch;
|
struct sk_buff *frag;
|
struct ppp_channel *chan;
|
|
totspeed = 0; /*total bitrate of the bundle*/
|
nfree = 0; /* # channels which have no packet already queued */
|
navail = 0; /* total # of usable channels (not deregistered) */
|
nzero = 0; /* number of channels with zero speed associated*/
|
totfree = 0; /*total # of channels available and
|
*having no queued packets before
|
*starting the fragmentation*/
|
|
hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
|
i = 0;
|
list_for_each_entry(pch, &ppp->channels, clist) {
|
if (pch->chan) {
|
pch->avail = 1;
|
navail++;
|
pch->speed = pch->chan->speed;
|
} else {
|
pch->avail = 0;
|
}
|
if (pch->avail) {
|
if (skb_queue_empty(&pch->file.xq) ||
|
!pch->had_frag) {
|
if (pch->speed == 0)
|
nzero++;
|
else
|
totspeed += pch->speed;
|
|
pch->avail = 2;
|
++nfree;
|
++totfree;
|
}
|
if (!pch->had_frag && i < ppp->nxchan)
|
ppp->nxchan = i;
|
}
|
++i;
|
}
|
/*
|
* Don't start sending this packet unless at least half of
|
* the channels are free. This gives much better TCP
|
* performance if we have a lot of channels.
|
*/
|
if (nfree == 0 || nfree < navail / 2)
|
return 0; /* can't take now, leave it in xmit_pending */
|
|
/* Do protocol field compression */
|
p = skb->data;
|
len = skb->len;
|
if (*p == 0 && mp_protocol_compress) {
|
++p;
|
--len;
|
}
|
|
totlen = len;
|
nbigger = len % nfree;
|
|
/* skip to the channel after the one we last used
|
and start at that one */
|
list = &ppp->channels;
|
for (i = 0; i < ppp->nxchan; ++i) {
|
list = list->next;
|
if (list == &ppp->channels) {
|
i = 0;
|
break;
|
}
|
}
|
|
/* create a fragment for each channel */
|
bits = B;
|
while (len > 0) {
|
list = list->next;
|
if (list == &ppp->channels) {
|
i = 0;
|
continue;
|
}
|
pch = list_entry(list, struct channel, clist);
|
++i;
|
if (!pch->avail)
|
continue;
|
|
/*
|
* Skip this channel if it has a fragment pending already and
|
* we haven't given a fragment to all of the free channels.
|
*/
|
if (pch->avail == 1) {
|
if (nfree > 0)
|
continue;
|
} else {
|
pch->avail = 1;
|
}
|
|
/* check the channel's mtu and whether it is still attached. */
|
spin_lock(&pch->downl);
|
if (pch->chan == NULL) {
|
/* can't use this channel, it's being deregistered */
|
if (pch->speed == 0)
|
nzero--;
|
else
|
totspeed -= pch->speed;
|
|
spin_unlock(&pch->downl);
|
pch->avail = 0;
|
totlen = len;
|
totfree--;
|
nfree--;
|
if (--navail == 0)
|
break;
|
continue;
|
}
|
|
/*
|
*if the channel speed is not set divide
|
*the packet evenly among the free channels;
|
*otherwise divide it according to the speed
|
*of the channel we are going to transmit on
|
*/
|
flen = len;
|
if (nfree > 0) {
|
if (pch->speed == 0) {
|
flen = len/nfree;
|
if (nbigger > 0) {
|
flen++;
|
nbigger--;
|
}
|
} else {
|
flen = (((totfree - nzero)*(totlen + hdrlen*totfree)) /
|
((totspeed*totfree)/pch->speed)) - hdrlen;
|
if (nbigger > 0) {
|
flen += ((totfree - nzero)*pch->speed)/totspeed;
|
nbigger -= ((totfree - nzero)*pch->speed)/
|
totspeed;
|
}
|
}
|
nfree--;
|
}
|
|
/*
|
*check if we are on the last channel or
|
*we exceded the length of the data to
|
*fragment
|
*/
|
if ((nfree <= 0) || (flen > len))
|
flen = len;
|
/*
|
*it is not worth to tx on slow channels:
|
*in that case from the resulting flen according to the
|
*above formula will be equal or less than zero.
|
*Skip the channel in this case
|
*/
|
if (flen <= 0) {
|
pch->avail = 2;
|
spin_unlock(&pch->downl);
|
continue;
|
}
|
|
/*
|
* hdrlen includes the 2-byte PPP protocol field, but the
|
* MTU counts only the payload excluding the protocol field.
|
* (RFC1661 Section 2)
|
*/
|
mtu = pch->chan->mtu - (hdrlen - 2);
|
if (mtu < 4)
|
mtu = 4;
|
if (flen > mtu)
|
flen = mtu;
|
if (flen == len)
|
bits |= E;
|
frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
|
if (!frag)
|
goto noskb;
|
q = skb_put(frag, flen + hdrlen);
|
|
/* make the MP header */
|
put_unaligned_be16(PPP_MP, q);
|
if (ppp->flags & SC_MP_XSHORTSEQ) {
|
q[2] = bits + ((ppp->nxseq >> 8) & 0xf);
|
q[3] = ppp->nxseq;
|
} else {
|
q[2] = bits;
|
q[3] = ppp->nxseq >> 16;
|
q[4] = ppp->nxseq >> 8;
|
q[5] = ppp->nxseq;
|
}
|
|
memcpy(q + hdrlen, p, flen);
|
|
/* try to send it down the channel */
|
chan = pch->chan;
|
if (!skb_queue_empty(&pch->file.xq) ||
|
!chan->ops->start_xmit(chan, frag))
|
skb_queue_tail(&pch->file.xq, frag);
|
pch->had_frag = 1;
|
p += flen;
|
len -= flen;
|
++ppp->nxseq;
|
bits = 0;
|
spin_unlock(&pch->downl);
|
}
|
ppp->nxchan = i;
|
|
return 1;
|
|
noskb:
|
spin_unlock(&pch->downl);
|
if (ppp->debug & 1)
|
netdev_err(ppp->dev, "PPP: no memory (fragment)\n");
|
++ppp->dev->stats.tx_errors;
|
++ppp->nxseq;
|
return 1; /* abandon the frame */
|
}
|
#endif /* CONFIG_PPP_MULTILINK */
|
|
/* Try to send data out on a channel */
|
static void __ppp_channel_push(struct channel *pch)
|
{
|
struct sk_buff *skb;
|
struct ppp *ppp;
|
|
spin_lock(&pch->downl);
|
if (pch->chan) {
|
while (!skb_queue_empty(&pch->file.xq)) {
|
skb = skb_dequeue(&pch->file.xq);
|
if (!pch->chan->ops->start_xmit(pch->chan, skb)) {
|
/* put the packet back and try again later */
|
skb_queue_head(&pch->file.xq, skb);
|
break;
|
}
|
}
|
} else {
|
/* channel got deregistered */
|
skb_queue_purge(&pch->file.xq);
|
}
|
spin_unlock(&pch->downl);
|
/* see if there is anything from the attached unit to be sent */
|
if (skb_queue_empty(&pch->file.xq)) {
|
ppp = pch->ppp;
|
if (ppp)
|
__ppp_xmit_process(ppp, NULL);
|
}
|
}
|
|
static void ppp_channel_push(struct channel *pch)
|
{
|
read_lock_bh(&pch->upl);
|
if (pch->ppp) {
|
(*this_cpu_ptr(pch->ppp->xmit_recursion))++;
|
__ppp_channel_push(pch);
|
(*this_cpu_ptr(pch->ppp->xmit_recursion))--;
|
} else {
|
__ppp_channel_push(pch);
|
}
|
read_unlock_bh(&pch->upl);
|
}
|
|
/*
|
* Receive-side routines.
|
*/
|
|
struct ppp_mp_skb_parm {
|
u32 sequence;
|
u8 BEbits;
|
};
|
#define PPP_MP_CB(skb) ((struct ppp_mp_skb_parm *)((skb)->cb))
|
|
static inline void
|
ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
|
{
|
ppp_recv_lock(ppp);
|
if (!ppp->closing)
|
ppp_receive_frame(ppp, skb, pch);
|
else
|
kfree_skb(skb);
|
ppp_recv_unlock(ppp);
|
}
|
|
/**
|
* __ppp_decompress_proto - Decompress protocol field, slim version.
|
* @skb: Socket buffer where protocol field should be decompressed. It must have
|
* at least 1 byte of head room and 1 byte of linear data. First byte of
|
* data must be a protocol field byte.
|
*
|
* Decompress protocol field in PPP header if it's compressed, e.g. when
|
* Protocol-Field-Compression (PFC) was negotiated. No checks w.r.t. skb data
|
* length are done in this function.
|
*/
|
static void __ppp_decompress_proto(struct sk_buff *skb)
|
{
|
if (skb->data[0] & 0x01)
|
*(u8 *)skb_push(skb, 1) = 0x00;
|
}
|
|
/**
|
* ppp_decompress_proto - Check skb data room and decompress protocol field.
|
* @skb: Socket buffer where protocol field should be decompressed. First byte
|
* of data must be a protocol field byte.
|
*
|
* Decompress protocol field in PPP header if it's compressed, e.g. when
|
* Protocol-Field-Compression (PFC) was negotiated. This function also makes
|
* sure that skb data room is sufficient for Protocol field, before and after
|
* decompression.
|
*
|
* Return: true - decompressed successfully, false - not enough room in skb.
|
*/
|
static bool ppp_decompress_proto(struct sk_buff *skb)
|
{
|
/* At least one byte should be present (if protocol is compressed) */
|
if (!pskb_may_pull(skb, 1))
|
return false;
|
|
__ppp_decompress_proto(skb);
|
|
/* Protocol field should occupy 2 bytes when not compressed */
|
return pskb_may_pull(skb, 2);
|
}
|
|
void
|
ppp_input(struct ppp_channel *chan, struct sk_buff *skb)
|
{
|
struct channel *pch = chan->ppp;
|
int proto;
|
|
if (!pch) {
|
kfree_skb(skb);
|
return;
|
}
|
|
read_lock_bh(&pch->upl);
|
if (!ppp_decompress_proto(skb)) {
|
kfree_skb(skb);
|
if (pch->ppp) {
|
++pch->ppp->dev->stats.rx_length_errors;
|
ppp_receive_error(pch->ppp);
|
}
|
goto done;
|
}
|
|
proto = PPP_PROTO(skb);
|
if (!pch->ppp || proto >= 0xc000 || proto == PPP_CCPFRAG) {
|
/* put it on the channel queue */
|
skb_queue_tail(&pch->file.rq, skb);
|
/* drop old frames if queue too long */
|
while (pch->file.rq.qlen > PPP_MAX_RQLEN &&
|
(skb = skb_dequeue(&pch->file.rq)))
|
kfree_skb(skb);
|
wake_up_interruptible(&pch->file.rwait);
|
} else {
|
ppp_do_recv(pch->ppp, skb, pch);
|
}
|
|
done:
|
read_unlock_bh(&pch->upl);
|
}
|
|
/* Put a 0-length skb in the receive queue as an error indication */
|
void
|
ppp_input_error(struct ppp_channel *chan, int code)
|
{
|
struct channel *pch = chan->ppp;
|
struct sk_buff *skb;
|
|
if (!pch)
|
return;
|
|
read_lock_bh(&pch->upl);
|
if (pch->ppp) {
|
skb = alloc_skb(0, GFP_ATOMIC);
|
if (skb) {
|
skb->len = 0; /* probably unnecessary */
|
skb->cb[0] = code;
|
ppp_do_recv(pch->ppp, skb, pch);
|
}
|
}
|
read_unlock_bh(&pch->upl);
|
}
|
|
/*
|
* We come in here to process a received frame.
|
* The receive side of the ppp unit is locked.
|
*/
|
static void
|
ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
|
{
|
/* note: a 0-length skb is used as an error indication */
|
if (skb->len > 0) {
|
skb_checksum_complete_unset(skb);
|
#ifdef CONFIG_PPP_MULTILINK
|
/* XXX do channel-level decompression here */
|
if (PPP_PROTO(skb) == PPP_MP)
|
ppp_receive_mp_frame(ppp, skb, pch);
|
else
|
#endif /* CONFIG_PPP_MULTILINK */
|
ppp_receive_nonmp_frame(ppp, skb);
|
} else {
|
kfree_skb(skb);
|
ppp_receive_error(ppp);
|
}
|
}
|
|
static void
|
ppp_receive_error(struct ppp *ppp)
|
{
|
++ppp->dev->stats.rx_errors;
|
if (ppp->vj)
|
slhc_toss(ppp->vj);
|
}
|
|
static void
|
ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb)
|
{
|
struct sk_buff *ns;
|
int proto, len, npi;
|
|
/*
|
* Decompress the frame, if compressed.
|
* Note that some decompressors need to see uncompressed frames
|
* that come in as well as compressed frames.
|
*/
|
if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN) &&
|
(ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0)
|
skb = ppp_decompress_frame(ppp, skb);
|
|
if (ppp->flags & SC_MUST_COMP && ppp->rstate & SC_DC_FERROR)
|
goto err;
|
|
/* At this point the "Protocol" field MUST be decompressed, either in
|
* ppp_input(), ppp_decompress_frame() or in ppp_receive_mp_frame().
|
*/
|
proto = PPP_PROTO(skb);
|
switch (proto) {
|
case PPP_VJC_COMP:
|
/* decompress VJ compressed packets */
|
if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP))
|
goto err;
|
|
if (skb_tailroom(skb) < 124 || skb_cloned(skb)) {
|
/* copy to a new sk_buff with more tailroom */
|
ns = dev_alloc_skb(skb->len + 128);
|
if (!ns) {
|
netdev_err(ppp->dev, "PPP: no memory "
|
"(VJ decomp)\n");
|
goto err;
|
}
|
skb_reserve(ns, 2);
|
skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len);
|
consume_skb(skb);
|
skb = ns;
|
}
|
else
|
skb->ip_summed = CHECKSUM_NONE;
|
|
len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2);
|
if (len <= 0) {
|
netdev_printk(KERN_DEBUG, ppp->dev,
|
"PPP: VJ decompression error\n");
|
goto err;
|
}
|
len += 2;
|
if (len > skb->len)
|
skb_put(skb, len - skb->len);
|
else if (len < skb->len)
|
skb_trim(skb, len);
|
proto = PPP_IP;
|
break;
|
|
case PPP_VJC_UNCOMP:
|
if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP))
|
goto err;
|
|
/* Until we fix the decompressor need to make sure
|
* data portion is linear.
|
*/
|
if (!pskb_may_pull(skb, skb->len))
|
goto err;
|
|
if (slhc_remember(ppp->vj, skb->data + 2, skb->len - 2) <= 0) {
|
netdev_err(ppp->dev, "PPP: VJ uncompressed error\n");
|
goto err;
|
}
|
proto = PPP_IP;
|
break;
|
|
case PPP_CCP:
|
ppp_ccp_peek(ppp, skb, 1);
|
break;
|
}
|
|
++ppp->stats64.rx_packets;
|
ppp->stats64.rx_bytes += skb->len - 2;
|
|
npi = proto_to_npindex(proto);
|
if (npi < 0) {
|
/* control or unknown frame - pass it to pppd */
|
skb_queue_tail(&ppp->file.rq, skb);
|
/* limit queue length by dropping old frames */
|
while (ppp->file.rq.qlen > PPP_MAX_RQLEN &&
|
(skb = skb_dequeue(&ppp->file.rq)))
|
kfree_skb(skb);
|
/* wake up any process polling or blocking on read */
|
wake_up_interruptible(&ppp->file.rwait);
|
|
} else {
|
/* network protocol frame - give it to the kernel */
|
|
#ifdef CONFIG_PPP_FILTER
|
/* check if the packet passes the pass and active filters */
|
/* the filter instructions are constructed assuming
|
a four-byte PPP header on each packet */
|
if (ppp->pass_filter || ppp->active_filter) {
|
if (skb_unclone(skb, GFP_ATOMIC))
|
goto err;
|
|
*(u8 *)skb_push(skb, 2) = 0;
|
if (ppp->pass_filter &&
|
BPF_PROG_RUN(ppp->pass_filter, skb) == 0) {
|
if (ppp->debug & 1)
|
netdev_printk(KERN_DEBUG, ppp->dev,
|
"PPP: inbound frame "
|
"not passed\n");
|
kfree_skb(skb);
|
return;
|
}
|
if (!(ppp->active_filter &&
|
BPF_PROG_RUN(ppp->active_filter, skb) == 0))
|
ppp->last_recv = jiffies;
|
__skb_pull(skb, 2);
|
} else
|
#endif /* CONFIG_PPP_FILTER */
|
ppp->last_recv = jiffies;
|
|
if ((ppp->dev->flags & IFF_UP) == 0 ||
|
ppp->npmode[npi] != NPMODE_PASS) {
|
kfree_skb(skb);
|
} else {
|
/* chop off protocol */
|
skb_pull_rcsum(skb, 2);
|
skb->dev = ppp->dev;
|
skb->protocol = htons(npindex_to_ethertype[npi]);
|
skb_reset_mac_header(skb);
|
skb_scrub_packet(skb, !net_eq(ppp->ppp_net,
|
dev_net(ppp->dev)));
|
netif_rx(skb);
|
}
|
}
|
return;
|
|
err:
|
kfree_skb(skb);
|
ppp_receive_error(ppp);
|
}
|
|
static struct sk_buff *
|
ppp_decompress_frame(struct ppp *ppp, struct sk_buff *skb)
|
{
|
int proto = PPP_PROTO(skb);
|
struct sk_buff *ns;
|
int len;
|
|
/* Until we fix all the decompressor's need to make sure
|
* data portion is linear.
|
*/
|
if (!pskb_may_pull(skb, skb->len))
|
goto err;
|
|
if (proto == PPP_COMP) {
|
int obuff_size;
|
|
switch(ppp->rcomp->compress_proto) {
|
case CI_MPPE:
|
obuff_size = ppp->mru + PPP_HDRLEN + 1;
|
break;
|
default:
|
obuff_size = ppp->mru + PPP_HDRLEN;
|
break;
|
}
|
|
ns = dev_alloc_skb(obuff_size);
|
if (!ns) {
|
netdev_err(ppp->dev, "ppp_decompress_frame: "
|
"no memory\n");
|
goto err;
|
}
|
/* the decompressor still expects the A/C bytes in the hdr */
|
len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2,
|
skb->len + 2, ns->data, obuff_size);
|
if (len < 0) {
|
/* Pass the compressed frame to pppd as an
|
error indication. */
|
if (len == DECOMP_FATALERROR)
|
ppp->rstate |= SC_DC_FERROR;
|
kfree_skb(ns);
|
goto err;
|
}
|
|
consume_skb(skb);
|
skb = ns;
|
skb_put(skb, len);
|
skb_pull(skb, 2); /* pull off the A/C bytes */
|
|
/* Don't call __ppp_decompress_proto() here, but instead rely on
|
* corresponding algo (mppe/bsd/deflate) to decompress it.
|
*/
|
} else {
|
/* Uncompressed frame - pass to decompressor so it
|
can update its dictionary if necessary. */
|
if (ppp->rcomp->incomp)
|
ppp->rcomp->incomp(ppp->rc_state, skb->data - 2,
|
skb->len + 2);
|
}
|
|
return skb;
|
|
err:
|
ppp->rstate |= SC_DC_ERROR;
|
ppp_receive_error(ppp);
|
return skb;
|
}
|
|
#ifdef CONFIG_PPP_MULTILINK
|
/*
|
* Receive a multilink frame.
|
* We put it on the reconstruction queue and then pull off
|
* as many completed frames as we can.
|
*/
|
static void
|
ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
|
{
|
u32 mask, seq;
|
struct channel *ch;
|
int mphdrlen = (ppp->flags & SC_MP_SHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
|
|
if (!pskb_may_pull(skb, mphdrlen + 1) || ppp->mrru == 0)
|
goto err; /* no good, throw it away */
|
|
/* Decode sequence number and begin/end bits */
|
if (ppp->flags & SC_MP_SHORTSEQ) {
|
seq = ((skb->data[2] & 0x0f) << 8) | skb->data[3];
|
mask = 0xfff;
|
} else {
|
seq = (skb->data[3] << 16) | (skb->data[4] << 8)| skb->data[5];
|
mask = 0xffffff;
|
}
|
PPP_MP_CB(skb)->BEbits = skb->data[2];
|
skb_pull(skb, mphdrlen); /* pull off PPP and MP headers */
|
|
/*
|
* Do protocol ID decompression on the first fragment of each packet.
|
* We have to do that here, because ppp_receive_nonmp_frame() expects
|
* decompressed protocol field.
|
*/
|
if (PPP_MP_CB(skb)->BEbits & B)
|
__ppp_decompress_proto(skb);
|
|
/*
|
* Expand sequence number to 32 bits, making it as close
|
* as possible to ppp->minseq.
|
*/
|
seq |= ppp->minseq & ~mask;
|
if ((int)(ppp->minseq - seq) > (int)(mask >> 1))
|
seq += mask + 1;
|
else if ((int)(seq - ppp->minseq) > (int)(mask >> 1))
|
seq -= mask + 1; /* should never happen */
|
PPP_MP_CB(skb)->sequence = seq;
|
pch->lastseq = seq;
|
|
/*
|
* If this packet comes before the next one we were expecting,
|
* drop it.
|
*/
|
if (seq_before(seq, ppp->nextseq)) {
|
kfree_skb(skb);
|
++ppp->dev->stats.rx_dropped;
|
ppp_receive_error(ppp);
|
return;
|
}
|
|
/*
|
* Reevaluate minseq, the minimum over all channels of the
|
* last sequence number received on each channel. Because of
|
* the increasing sequence number rule, we know that any fragment
|
* before `minseq' which hasn't arrived is never going to arrive.
|
* The list of channels can't change because we have the receive
|
* side of the ppp unit locked.
|
*/
|
list_for_each_entry(ch, &ppp->channels, clist) {
|
if (seq_before(ch->lastseq, seq))
|
seq = ch->lastseq;
|
}
|
if (seq_before(ppp->minseq, seq))
|
ppp->minseq = seq;
|
|
/* Put the fragment on the reconstruction queue */
|
ppp_mp_insert(ppp, skb);
|
|
/* If the queue is getting long, don't wait any longer for packets
|
before the start of the queue. */
|
if (skb_queue_len(&ppp->mrq) >= PPP_MP_MAX_QLEN) {
|
struct sk_buff *mskb = skb_peek(&ppp->mrq);
|
if (seq_before(ppp->minseq, PPP_MP_CB(mskb)->sequence))
|
ppp->minseq = PPP_MP_CB(mskb)->sequence;
|
}
|
|
/* Pull completed packets off the queue and receive them. */
|
while ((skb = ppp_mp_reconstruct(ppp))) {
|
if (pskb_may_pull(skb, 2))
|
ppp_receive_nonmp_frame(ppp, skb);
|
else {
|
++ppp->dev->stats.rx_length_errors;
|
kfree_skb(skb);
|
ppp_receive_error(ppp);
|
}
|
}
|
|
return;
|
|
err:
|
kfree_skb(skb);
|
ppp_receive_error(ppp);
|
}
|
|
/*
|
* Insert a fragment on the MP reconstruction queue.
|
* The queue is ordered by increasing sequence number.
|
*/
|
static void
|
ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb)
|
{
|
struct sk_buff *p;
|
struct sk_buff_head *list = &ppp->mrq;
|
u32 seq = PPP_MP_CB(skb)->sequence;
|
|
/* N.B. we don't need to lock the list lock because we have the
|
ppp unit receive-side lock. */
|
skb_queue_walk(list, p) {
|
if (seq_before(seq, PPP_MP_CB(p)->sequence))
|
break;
|
}
|
__skb_queue_before(list, p, skb);
|
}
|
|
/*
|
* Reconstruct a packet from the MP fragment queue.
|
* We go through increasing sequence numbers until we find a
|
* complete packet, or we get to the sequence number for a fragment
|
* which hasn't arrived but might still do so.
|
*/
|
static struct sk_buff *
|
ppp_mp_reconstruct(struct ppp *ppp)
|
{
|
u32 seq = ppp->nextseq;
|
u32 minseq = ppp->minseq;
|
struct sk_buff_head *list = &ppp->mrq;
|
struct sk_buff *p, *tmp;
|
struct sk_buff *head, *tail;
|
struct sk_buff *skb = NULL;
|
int lost = 0, len = 0;
|
|
if (ppp->mrru == 0) /* do nothing until mrru is set */
|
return NULL;
|
head = list->next;
|
tail = NULL;
|
skb_queue_walk_safe(list, p, tmp) {
|
again:
|
if (seq_before(PPP_MP_CB(p)->sequence, seq)) {
|
/* this can't happen, anyway ignore the skb */
|
netdev_err(ppp->dev, "ppp_mp_reconstruct bad "
|
"seq %u < %u\n",
|
PPP_MP_CB(p)->sequence, seq);
|
__skb_unlink(p, list);
|
kfree_skb(p);
|
continue;
|
}
|
if (PPP_MP_CB(p)->sequence != seq) {
|
u32 oldseq;
|
/* Fragment `seq' is missing. If it is after
|
minseq, it might arrive later, so stop here. */
|
if (seq_after(seq, minseq))
|
break;
|
/* Fragment `seq' is lost, keep going. */
|
lost = 1;
|
oldseq = seq;
|
seq = seq_before(minseq, PPP_MP_CB(p)->sequence)?
|
minseq + 1: PPP_MP_CB(p)->sequence;
|
|
if (ppp->debug & 1)
|
netdev_printk(KERN_DEBUG, ppp->dev,
|
"lost frag %u..%u\n",
|
oldseq, seq-1);
|
|
goto again;
|
}
|
|
/*
|
* At this point we know that all the fragments from
|
* ppp->nextseq to seq are either present or lost.
|
* Also, there are no complete packets in the queue
|
* that have no missing fragments and end before this
|
* fragment.
|
*/
|
|
/* B bit set indicates this fragment starts a packet */
|
if (PPP_MP_CB(p)->BEbits & B) {
|
head = p;
|
lost = 0;
|
len = 0;
|
}
|
|
len += p->len;
|
|
/* Got a complete packet yet? */
|
if (lost == 0 && (PPP_MP_CB(p)->BEbits & E) &&
|
(PPP_MP_CB(head)->BEbits & B)) {
|
if (len > ppp->mrru + 2) {
|
++ppp->dev->stats.rx_length_errors;
|
netdev_printk(KERN_DEBUG, ppp->dev,
|
"PPP: reconstructed packet"
|
" is too long (%d)\n", len);
|
} else {
|
tail = p;
|
break;
|
}
|
ppp->nextseq = seq + 1;
|
}
|
|
/*
|
* If this is the ending fragment of a packet,
|
* and we haven't found a complete valid packet yet,
|
* we can discard up to and including this fragment.
|
*/
|
if (PPP_MP_CB(p)->BEbits & E) {
|
struct sk_buff *tmp2;
|
|
skb_queue_reverse_walk_from_safe(list, p, tmp2) {
|
if (ppp->debug & 1)
|
netdev_printk(KERN_DEBUG, ppp->dev,
|
"discarding frag %u\n",
|
PPP_MP_CB(p)->sequence);
|
__skb_unlink(p, list);
|
kfree_skb(p);
|
}
|
head = skb_peek(list);
|
if (!head)
|
break;
|
}
|
++seq;
|
}
|
|
/* If we have a complete packet, copy it all into one skb. */
|
if (tail != NULL) {
|
/* If we have discarded any fragments,
|
signal a receive error. */
|
if (PPP_MP_CB(head)->sequence != ppp->nextseq) {
|
skb_queue_walk_safe(list, p, tmp) {
|
if (p == head)
|
break;
|
if (ppp->debug & 1)
|
netdev_printk(KERN_DEBUG, ppp->dev,
|
"discarding frag %u\n",
|
PPP_MP_CB(p)->sequence);
|
__skb_unlink(p, list);
|
kfree_skb(p);
|
}
|
|
if (ppp->debug & 1)
|
netdev_printk(KERN_DEBUG, ppp->dev,
|
" missed pkts %u..%u\n",
|
ppp->nextseq,
|
PPP_MP_CB(head)->sequence-1);
|
++ppp->dev->stats.rx_dropped;
|
ppp_receive_error(ppp);
|
}
|
|
skb = head;
|
if (head != tail) {
|
struct sk_buff **fragpp = &skb_shinfo(skb)->frag_list;
|
p = skb_queue_next(list, head);
|
__skb_unlink(skb, list);
|
skb_queue_walk_from_safe(list, p, tmp) {
|
__skb_unlink(p, list);
|
*fragpp = p;
|
p->next = NULL;
|
fragpp = &p->next;
|
|
skb->len += p->len;
|
skb->data_len += p->len;
|
skb->truesize += p->truesize;
|
|
if (p == tail)
|
break;
|
}
|
} else {
|
__skb_unlink(skb, list);
|
}
|
|
ppp->nextseq = PPP_MP_CB(tail)->sequence + 1;
|
}
|
|
return skb;
|
}
|
#endif /* CONFIG_PPP_MULTILINK */
|
|
/*
|
* Channel interface.
|
*/
|
|
/* Create a new, unattached ppp channel. */
|
int ppp_register_channel(struct ppp_channel *chan)
|
{
|
return ppp_register_net_channel(current->nsproxy->net_ns, chan);
|
}
|
|
/* Create a new, unattached ppp channel for specified net. */
|
int ppp_register_net_channel(struct net *net, struct ppp_channel *chan)
|
{
|
struct channel *pch;
|
struct ppp_net *pn;
|
|
pch = kzalloc(sizeof(struct channel), GFP_KERNEL);
|
if (!pch)
|
return -ENOMEM;
|
|
pn = ppp_pernet(net);
|
|
pch->ppp = NULL;
|
pch->chan = chan;
|
pch->chan_net = get_net(net);
|
chan->ppp = pch;
|
init_ppp_file(&pch->file, CHANNEL);
|
pch->file.hdrlen = chan->hdrlen;
|
#ifdef CONFIG_PPP_MULTILINK
|
pch->lastseq = -1;
|
#endif /* CONFIG_PPP_MULTILINK */
|
init_rwsem(&pch->chan_sem);
|
spin_lock_init(&pch->downl);
|
rwlock_init(&pch->upl);
|
|
spin_lock_bh(&pn->all_channels_lock);
|
pch->file.index = ++pn->last_channel_index;
|
list_add(&pch->list, &pn->new_channels);
|
atomic_inc(&channel_count);
|
spin_unlock_bh(&pn->all_channels_lock);
|
|
return 0;
|
}
|
|
/*
|
* Return the index of a channel.
|
*/
|
int ppp_channel_index(struct ppp_channel *chan)
|
{
|
struct channel *pch = chan->ppp;
|
|
if (pch)
|
return pch->file.index;
|
return -1;
|
}
|
|
/*
|
* Return the PPP unit number to which a channel is connected.
|
*/
|
int ppp_unit_number(struct ppp_channel *chan)
|
{
|
struct channel *pch = chan->ppp;
|
int unit = -1;
|
|
if (pch) {
|
read_lock_bh(&pch->upl);
|
if (pch->ppp)
|
unit = pch->ppp->file.index;
|
read_unlock_bh(&pch->upl);
|
}
|
return unit;
|
}
|
|
/*
|
* Return the PPP device interface name of a channel.
|
*/
|
char *ppp_dev_name(struct ppp_channel *chan)
|
{
|
struct channel *pch = chan->ppp;
|
char *name = NULL;
|
|
if (pch) {
|
read_lock_bh(&pch->upl);
|
if (pch->ppp && pch->ppp->dev)
|
name = pch->ppp->dev->name;
|
read_unlock_bh(&pch->upl);
|
}
|
return name;
|
}
|
|
|
/*
|
* Disconnect a channel from the generic layer.
|
* This must be called in process context.
|
*/
|
void
|
ppp_unregister_channel(struct ppp_channel *chan)
|
{
|
struct channel *pch = chan->ppp;
|
struct ppp_net *pn;
|
|
if (!pch)
|
return; /* should never happen */
|
|
chan->ppp = NULL;
|
|
/*
|
* This ensures that we have returned from any calls into the
|
* the channel's start_xmit or ioctl routine before we proceed.
|
*/
|
down_write(&pch->chan_sem);
|
spin_lock_bh(&pch->downl);
|
pch->chan = NULL;
|
spin_unlock_bh(&pch->downl);
|
up_write(&pch->chan_sem);
|
ppp_disconnect_channel(pch);
|
|
pn = ppp_pernet(pch->chan_net);
|
spin_lock_bh(&pn->all_channels_lock);
|
list_del(&pch->list);
|
spin_unlock_bh(&pn->all_channels_lock);
|
|
pch->file.dead = 1;
|
wake_up_interruptible(&pch->file.rwait);
|
if (refcount_dec_and_test(&pch->file.refcnt))
|
ppp_destroy_channel(pch);
|
}
|
|
/*
|
* Callback from a channel when it can accept more to transmit.
|
* This should be called at BH/softirq level, not interrupt level.
|
*/
|
void
|
ppp_output_wakeup(struct ppp_channel *chan)
|
{
|
struct channel *pch = chan->ppp;
|
|
if (!pch)
|
return;
|
ppp_channel_push(pch);
|
}
|
|
/*
|
* Compression control.
|
*/
|
|
/* Process the PPPIOCSCOMPRESS ioctl. */
|
static int
|
ppp_set_compress(struct ppp *ppp, unsigned long arg)
|
{
|
int err;
|
struct compressor *cp, *ocomp;
|
struct ppp_option_data data;
|
void *state, *ostate;
|
unsigned char ccp_option[CCP_MAX_OPTION_LENGTH];
|
|
err = -EFAULT;
|
if (copy_from_user(&data, (void __user *) arg, sizeof(data)))
|
goto out;
|
if (data.length > CCP_MAX_OPTION_LENGTH)
|
goto out;
|
if (copy_from_user(ccp_option, (void __user *) data.ptr, data.length))
|
goto out;
|
|
err = -EINVAL;
|
if (data.length < 2 || ccp_option[1] < 2 || ccp_option[1] > data.length)
|
goto out;
|
|
cp = try_then_request_module(
|
find_compressor(ccp_option[0]),
|
"ppp-compress-%d", ccp_option[0]);
|
if (!cp)
|
goto out;
|
|
err = -ENOBUFS;
|
if (data.transmit) {
|
state = cp->comp_alloc(ccp_option, data.length);
|
if (state) {
|
ppp_xmit_lock(ppp);
|
ppp->xstate &= ~SC_COMP_RUN;
|
ocomp = ppp->xcomp;
|
ostate = ppp->xc_state;
|
ppp->xcomp = cp;
|
ppp->xc_state = state;
|
ppp_xmit_unlock(ppp);
|
if (ostate) {
|
ocomp->comp_free(ostate);
|
module_put(ocomp->owner);
|
}
|
err = 0;
|
} else
|
module_put(cp->owner);
|
|
} else {
|
state = cp->decomp_alloc(ccp_option, data.length);
|
if (state) {
|
ppp_recv_lock(ppp);
|
ppp->rstate &= ~SC_DECOMP_RUN;
|
ocomp = ppp->rcomp;
|
ostate = ppp->rc_state;
|
ppp->rcomp = cp;
|
ppp->rc_state = state;
|
ppp_recv_unlock(ppp);
|
if (ostate) {
|
ocomp->decomp_free(ostate);
|
module_put(ocomp->owner);
|
}
|
err = 0;
|
} else
|
module_put(cp->owner);
|
}
|
|
out:
|
return err;
|
}
|
|
/*
|
* Look at a CCP packet and update our state accordingly.
|
* We assume the caller has the xmit or recv path locked.
|
*/
|
static void
|
ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound)
|
{
|
unsigned char *dp;
|
int len;
|
|
if (!pskb_may_pull(skb, CCP_HDRLEN + 2))
|
return; /* no header */
|
dp = skb->data + 2;
|
|
switch (CCP_CODE(dp)) {
|
case CCP_CONFREQ:
|
|
/* A ConfReq starts negotiation of compression
|
* in one direction of transmission,
|
* and hence brings it down...but which way?
|
*
|
* Remember:
|
* A ConfReq indicates what the sender would like to receive
|
*/
|
if(inbound)
|
/* He is proposing what I should send */
|
ppp->xstate &= ~SC_COMP_RUN;
|
else
|
/* I am proposing to what he should send */
|
ppp->rstate &= ~SC_DECOMP_RUN;
|
|
break;
|
|
case CCP_TERMREQ:
|
case CCP_TERMACK:
|
/*
|
* CCP is going down, both directions of transmission
|
*/
|
ppp->rstate &= ~SC_DECOMP_RUN;
|
ppp->xstate &= ~SC_COMP_RUN;
|
break;
|
|
case CCP_CONFACK:
|
if ((ppp->flags & (SC_CCP_OPEN | SC_CCP_UP)) != SC_CCP_OPEN)
|
break;
|
len = CCP_LENGTH(dp);
|
if (!pskb_may_pull(skb, len + 2))
|
return; /* too short */
|
dp += CCP_HDRLEN;
|
len -= CCP_HDRLEN;
|
if (len < CCP_OPT_MINLEN || len < CCP_OPT_LENGTH(dp))
|
break;
|
if (inbound) {
|
/* we will start receiving compressed packets */
|
if (!ppp->rc_state)
|
break;
|
if (ppp->rcomp->decomp_init(ppp->rc_state, dp, len,
|
ppp->file.index, 0, ppp->mru, ppp->debug)) {
|
ppp->rstate |= SC_DECOMP_RUN;
|
ppp->rstate &= ~(SC_DC_ERROR | SC_DC_FERROR);
|
}
|
} else {
|
/* we will soon start sending compressed packets */
|
if (!ppp->xc_state)
|
break;
|
if (ppp->xcomp->comp_init(ppp->xc_state, dp, len,
|
ppp->file.index, 0, ppp->debug))
|
ppp->xstate |= SC_COMP_RUN;
|
}
|
break;
|
|
case CCP_RESETACK:
|
/* reset the [de]compressor */
|
if ((ppp->flags & SC_CCP_UP) == 0)
|
break;
|
if (inbound) {
|
if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN)) {
|
ppp->rcomp->decomp_reset(ppp->rc_state);
|
ppp->rstate &= ~SC_DC_ERROR;
|
}
|
} else {
|
if (ppp->xc_state && (ppp->xstate & SC_COMP_RUN))
|
ppp->xcomp->comp_reset(ppp->xc_state);
|
}
|
break;
|
}
|
}
|
|
/* Free up compression resources. */
|
static void
|
ppp_ccp_closed(struct ppp *ppp)
|
{
|
void *xstate, *rstate;
|
struct compressor *xcomp, *rcomp;
|
|
ppp_lock(ppp);
|
ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP);
|
ppp->xstate = 0;
|
xcomp = ppp->xcomp;
|
xstate = ppp->xc_state;
|
ppp->xc_state = NULL;
|
ppp->rstate = 0;
|
rcomp = ppp->rcomp;
|
rstate = ppp->rc_state;
|
ppp->rc_state = NULL;
|
ppp_unlock(ppp);
|
|
if (xstate) {
|
xcomp->comp_free(xstate);
|
module_put(xcomp->owner);
|
}
|
if (rstate) {
|
rcomp->decomp_free(rstate);
|
module_put(rcomp->owner);
|
}
|
}
|
|
/* List of compressors. */
|
static LIST_HEAD(compressor_list);
|
static DEFINE_SPINLOCK(compressor_list_lock);
|
|
struct compressor_entry {
|
struct list_head list;
|
struct compressor *comp;
|
};
|
|
static struct compressor_entry *
|
find_comp_entry(int proto)
|
{
|
struct compressor_entry *ce;
|
|
list_for_each_entry(ce, &compressor_list, list) {
|
if (ce->comp->compress_proto == proto)
|
return ce;
|
}
|
return NULL;
|
}
|
|
/* Register a compressor */
|
int
|
ppp_register_compressor(struct compressor *cp)
|
{
|
struct compressor_entry *ce;
|
int ret;
|
spin_lock(&compressor_list_lock);
|
ret = -EEXIST;
|
if (find_comp_entry(cp->compress_proto))
|
goto out;
|
ret = -ENOMEM;
|
ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC);
|
if (!ce)
|
goto out;
|
ret = 0;
|
ce->comp = cp;
|
list_add(&ce->list, &compressor_list);
|
out:
|
spin_unlock(&compressor_list_lock);
|
return ret;
|
}
|
|
/* Unregister a compressor */
|
void
|
ppp_unregister_compressor(struct compressor *cp)
|
{
|
struct compressor_entry *ce;
|
|
spin_lock(&compressor_list_lock);
|
ce = find_comp_entry(cp->compress_proto);
|
if (ce && ce->comp == cp) {
|
list_del(&ce->list);
|
kfree(ce);
|
}
|
spin_unlock(&compressor_list_lock);
|
}
|
|
/* Find a compressor. */
|
static struct compressor *
|
find_compressor(int type)
|
{
|
struct compressor_entry *ce;
|
struct compressor *cp = NULL;
|
|
spin_lock(&compressor_list_lock);
|
ce = find_comp_entry(type);
|
if (ce) {
|
cp = ce->comp;
|
if (!try_module_get(cp->owner))
|
cp = NULL;
|
}
|
spin_unlock(&compressor_list_lock);
|
return cp;
|
}
|
|
/*
|
* Miscelleneous stuff.
|
*/
|
|
static void
|
ppp_get_stats(struct ppp *ppp, struct ppp_stats *st)
|
{
|
struct slcompress *vj = ppp->vj;
|
|
memset(st, 0, sizeof(*st));
|
st->p.ppp_ipackets = ppp->stats64.rx_packets;
|
st->p.ppp_ierrors = ppp->dev->stats.rx_errors;
|
st->p.ppp_ibytes = ppp->stats64.rx_bytes;
|
st->p.ppp_opackets = ppp->stats64.tx_packets;
|
st->p.ppp_oerrors = ppp->dev->stats.tx_errors;
|
st->p.ppp_obytes = ppp->stats64.tx_bytes;
|
if (!vj)
|
return;
|
st->vj.vjs_packets = vj->sls_o_compressed + vj->sls_o_uncompressed;
|
st->vj.vjs_compressed = vj->sls_o_compressed;
|
st->vj.vjs_searches = vj->sls_o_searches;
|
st->vj.vjs_misses = vj->sls_o_misses;
|
st->vj.vjs_errorin = vj->sls_i_error;
|
st->vj.vjs_tossed = vj->sls_i_tossed;
|
st->vj.vjs_uncompressedin = vj->sls_i_uncompressed;
|
st->vj.vjs_compressedin = vj->sls_i_compressed;
|
}
|
|
/*
|
* Stuff for handling the lists of ppp units and channels
|
* and for initialization.
|
*/
|
|
/*
|
* Create a new ppp interface unit. Fails if it can't allocate memory
|
* or if there is already a unit with the requested number.
|
* unit == -1 means allocate a new number.
|
*/
|
static int ppp_create_interface(struct net *net, struct file *file, int *unit)
|
{
|
struct ppp_config conf = {
|
.file = file,
|
.unit = *unit,
|
.ifname_is_set = false,
|
};
|
struct net_device *dev;
|
struct ppp *ppp;
|
int err;
|
|
dev = alloc_netdev(sizeof(struct ppp), "", NET_NAME_ENUM, ppp_setup);
|
if (!dev) {
|
err = -ENOMEM;
|
goto err;
|
}
|
dev_net_set(dev, net);
|
dev->rtnl_link_ops = &ppp_link_ops;
|
|
rtnl_lock();
|
|
err = ppp_dev_configure(net, dev, &conf);
|
if (err < 0)
|
goto err_dev;
|
ppp = netdev_priv(dev);
|
*unit = ppp->file.index;
|
|
rtnl_unlock();
|
|
return 0;
|
|
err_dev:
|
rtnl_unlock();
|
free_netdev(dev);
|
err:
|
return err;
|
}
|
|
/*
|
* Initialize a ppp_file structure.
|
*/
|
static void
|
init_ppp_file(struct ppp_file *pf, int kind)
|
{
|
pf->kind = kind;
|
skb_queue_head_init(&pf->xq);
|
skb_queue_head_init(&pf->rq);
|
refcount_set(&pf->refcnt, 1);
|
init_waitqueue_head(&pf->rwait);
|
}
|
|
/*
|
* Free the memory used by a ppp unit. This is only called once
|
* there are no channels connected to the unit and no file structs
|
* that reference the unit.
|
*/
|
static void ppp_destroy_interface(struct ppp *ppp)
|
{
|
atomic_dec(&ppp_unit_count);
|
|
if (!ppp->file.dead || ppp->n_channels) {
|
/* "can't happen" */
|
netdev_err(ppp->dev, "ppp: destroying ppp struct %p "
|
"but dead=%d n_channels=%d !\n",
|
ppp, ppp->file.dead, ppp->n_channels);
|
return;
|
}
|
|
ppp_ccp_closed(ppp);
|
if (ppp->vj) {
|
slhc_free(ppp->vj);
|
ppp->vj = NULL;
|
}
|
skb_queue_purge(&ppp->file.xq);
|
skb_queue_purge(&ppp->file.rq);
|
#ifdef CONFIG_PPP_MULTILINK
|
skb_queue_purge(&ppp->mrq);
|
#endif /* CONFIG_PPP_MULTILINK */
|
#ifdef CONFIG_PPP_FILTER
|
if (ppp->pass_filter) {
|
bpf_prog_destroy(ppp->pass_filter);
|
ppp->pass_filter = NULL;
|
}
|
|
if (ppp->active_filter) {
|
bpf_prog_destroy(ppp->active_filter);
|
ppp->active_filter = NULL;
|
}
|
#endif /* CONFIG_PPP_FILTER */
|
|
kfree_skb(ppp->xmit_pending);
|
free_percpu(ppp->xmit_recursion);
|
|
free_netdev(ppp->dev);
|
}
|
|
/*
|
* Locate an existing ppp unit.
|
* The caller should have locked the all_ppp_mutex.
|
*/
|
static struct ppp *
|
ppp_find_unit(struct ppp_net *pn, int unit)
|
{
|
return unit_find(&pn->units_idr, unit);
|
}
|
|
/*
|
* Locate an existing ppp channel.
|
* The caller should have locked the all_channels_lock.
|
* First we look in the new_channels list, then in the
|
* all_channels list. If found in the new_channels list,
|
* we move it to the all_channels list. This is for speed
|
* when we have a lot of channels in use.
|
*/
|
static struct channel *
|
ppp_find_channel(struct ppp_net *pn, int unit)
|
{
|
struct channel *pch;
|
|
list_for_each_entry(pch, &pn->new_channels, list) {
|
if (pch->file.index == unit) {
|
list_move(&pch->list, &pn->all_channels);
|
return pch;
|
}
|
}
|
|
list_for_each_entry(pch, &pn->all_channels, list) {
|
if (pch->file.index == unit)
|
return pch;
|
}
|
|
return NULL;
|
}
|
|
/*
|
* Connect a PPP channel to a PPP interface unit.
|
*/
|
static int
|
ppp_connect_channel(struct channel *pch, int unit)
|
{
|
struct ppp *ppp;
|
struct ppp_net *pn;
|
int ret = -ENXIO;
|
int hdrlen;
|
|
pn = ppp_pernet(pch->chan_net);
|
|
mutex_lock(&pn->all_ppp_mutex);
|
ppp = ppp_find_unit(pn, unit);
|
if (!ppp)
|
goto out;
|
write_lock_bh(&pch->upl);
|
ret = -EINVAL;
|
if (pch->ppp)
|
goto outl;
|
|
ppp_lock(ppp);
|
spin_lock_bh(&pch->downl);
|
if (!pch->chan) {
|
/* Don't connect unregistered channels */
|
spin_unlock_bh(&pch->downl);
|
ppp_unlock(ppp);
|
ret = -ENOTCONN;
|
goto outl;
|
}
|
spin_unlock_bh(&pch->downl);
|
if (pch->file.hdrlen > ppp->file.hdrlen)
|
ppp->file.hdrlen = pch->file.hdrlen;
|
hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */
|
if (hdrlen > ppp->dev->hard_header_len)
|
ppp->dev->hard_header_len = hdrlen;
|
list_add_tail(&pch->clist, &ppp->channels);
|
++ppp->n_channels;
|
pch->ppp = ppp;
|
refcount_inc(&ppp->file.refcnt);
|
ppp_unlock(ppp);
|
ret = 0;
|
|
outl:
|
write_unlock_bh(&pch->upl);
|
out:
|
mutex_unlock(&pn->all_ppp_mutex);
|
return ret;
|
}
|
|
/*
|
* Disconnect a channel from its ppp unit.
|
*/
|
static int
|
ppp_disconnect_channel(struct channel *pch)
|
{
|
struct ppp *ppp;
|
int err = -EINVAL;
|
|
write_lock_bh(&pch->upl);
|
ppp = pch->ppp;
|
pch->ppp = NULL;
|
write_unlock_bh(&pch->upl);
|
if (ppp) {
|
/* remove it from the ppp unit's list */
|
ppp_lock(ppp);
|
list_del(&pch->clist);
|
if (--ppp->n_channels == 0)
|
wake_up_interruptible(&ppp->file.rwait);
|
ppp_unlock(ppp);
|
if (refcount_dec_and_test(&ppp->file.refcnt))
|
ppp_destroy_interface(ppp);
|
err = 0;
|
}
|
return err;
|
}
|
|
/*
|
* Free up the resources used by a ppp channel.
|
*/
|
static void ppp_destroy_channel(struct channel *pch)
|
{
|
put_net(pch->chan_net);
|
pch->chan_net = NULL;
|
|
atomic_dec(&channel_count);
|
|
if (!pch->file.dead) {
|
/* "can't happen" */
|
pr_err("ppp: destroying undead channel %p !\n", pch);
|
return;
|
}
|
skb_queue_purge(&pch->file.xq);
|
skb_queue_purge(&pch->file.rq);
|
kfree(pch);
|
}
|
|
static void __exit ppp_cleanup(void)
|
{
|
/* should never happen */
|
if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count))
|
pr_err("PPP: removing module but units remain!\n");
|
rtnl_link_unregister(&ppp_link_ops);
|
unregister_chrdev(PPP_MAJOR, "ppp");
|
device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0));
|
class_destroy(ppp_class);
|
unregister_pernet_device(&ppp_net_ops);
|
}
|
|
/*
|
* Units handling. Caller must protect concurrent access
|
* by holding all_ppp_mutex
|
*/
|
|
/* associate pointer with specified number */
|
static int unit_set(struct idr *p, void *ptr, int n)
|
{
|
int unit;
|
|
unit = idr_alloc(p, ptr, n, n + 1, GFP_KERNEL);
|
if (unit == -ENOSPC)
|
unit = -EINVAL;
|
return unit;
|
}
|
|
/* get new free unit number and associate pointer with it */
|
static int unit_get(struct idr *p, void *ptr, int min)
|
{
|
return idr_alloc(p, ptr, min, 0, GFP_KERNEL);
|
}
|
|
/* put unit number back to a pool */
|
static void unit_put(struct idr *p, int n)
|
{
|
idr_remove(p, n);
|
}
|
|
/* get pointer associated with the number */
|
static void *unit_find(struct idr *p, int n)
|
{
|
return idr_find(p, n);
|
}
|
|
/* Module/initialization stuff */
|
|
module_init(ppp_init);
|
module_exit(ppp_cleanup);
|
|
EXPORT_SYMBOL(ppp_register_net_channel);
|
EXPORT_SYMBOL(ppp_register_channel);
|
EXPORT_SYMBOL(ppp_unregister_channel);
|
EXPORT_SYMBOL(ppp_channel_index);
|
EXPORT_SYMBOL(ppp_unit_number);
|
EXPORT_SYMBOL(ppp_dev_name);
|
EXPORT_SYMBOL(ppp_input);
|
EXPORT_SYMBOL(ppp_input_error);
|
EXPORT_SYMBOL(ppp_output_wakeup);
|
EXPORT_SYMBOL(ppp_register_compressor);
|
EXPORT_SYMBOL(ppp_unregister_compressor);
|
MODULE_LICENSE("GPL");
|
MODULE_ALIAS_CHARDEV(PPP_MAJOR, 0);
|
MODULE_ALIAS_RTNL_LINK("ppp");
|
MODULE_ALIAS("devname:ppp");
|
