2776 lines
66 KiB
C
2776 lines
66 KiB
C
/*
|
|
* 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/config.h>
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/kmod.h>
|
|
#include <linux/init.h>
|
|
#include <linux/list.h>
|
|
#include <linux/devfs_fs_kernel.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/poll.h>
|
|
#include <linux/ppp_defs.h>
|
|
#include <linux/filter.h>
|
|
#include <linux/if_ppp.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/smp_lock.h>
|
|
#include <linux/rwsem.h>
|
|
#include <linux/stddef.h>
|
|
#include <linux/device.h>
|
|
#include <net/slhc_vj.h>
|
|
#include <asm/atomic.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 MIN_FRAG_SIZE 64
|
|
|
|
/*
|
|
* 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 */
|
|
atomic_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) ((X *)((char *)(pf) - offsetof(X, file)))
|
|
|
|
#define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp)
|
|
#define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel)
|
|
|
|
#define ROUNDUP(n, x) (((n) + (x) - 1) / (x))
|
|
|
|
/*
|
|
* 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 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 */
|
|
#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 */
|
|
struct net_device_stats stats; /* statistics */
|
|
#ifdef CONFIG_PPP_FILTER
|
|
struct sock_filter *pass_filter; /* filter for packets to pass */
|
|
struct sock_filter *active_filter;/* filter for pkts to reset idle */
|
|
unsigned pass_len, active_len;
|
|
#endif /* CONFIG_PPP_FILTER */
|
|
};
|
|
|
|
/*
|
|
* 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.
|
|
* 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)
|
|
|
|
/*
|
|
* 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 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 */
|
|
#endif /* CONFIG_PPP_MULTILINK */
|
|
};
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
|
|
/*
|
|
* A cardmap represents a mapping from unsigned integers to pointers,
|
|
* and provides a fast "find lowest unused number" operation.
|
|
* It uses a broad (32-way) tree with a bitmap at each level.
|
|
* It is designed to be space-efficient for small numbers of entries
|
|
* and time-efficient for large numbers of entries.
|
|
*/
|
|
#define CARDMAP_ORDER 5
|
|
#define CARDMAP_WIDTH (1U << CARDMAP_ORDER)
|
|
#define CARDMAP_MASK (CARDMAP_WIDTH - 1)
|
|
|
|
struct cardmap {
|
|
int shift;
|
|
unsigned long inuse;
|
|
struct cardmap *parent;
|
|
void *ptr[CARDMAP_WIDTH];
|
|
};
|
|
static void *cardmap_get(struct cardmap *map, unsigned int nr);
|
|
static void cardmap_set(struct cardmap **map, unsigned int nr, void *ptr);
|
|
static unsigned int cardmap_find_first_free(struct cardmap *map);
|
|
static void cardmap_destroy(struct cardmap **map);
|
|
|
|
/*
|
|
* all_ppp_sem protects the all_ppp_units mapping.
|
|
* It also ensures that finding a ppp unit in the all_ppp_units map
|
|
* and updating its file.refcnt field is atomic.
|
|
*/
|
|
static DECLARE_MUTEX(all_ppp_sem);
|
|
static struct cardmap *all_ppp_units;
|
|
static atomic_t ppp_unit_count = ATOMIC_INIT(0);
|
|
|
|
/*
|
|
* all_channels_lock protects all_channels and last_channel_index,
|
|
* and the atomicity of find a channel and updating its file.refcnt
|
|
* field.
|
|
*/
|
|
static DEFINE_SPINLOCK(all_channels_lock);
|
|
static LIST_HEAD(all_channels);
|
|
static LIST_HEAD(new_channels);
|
|
static int last_channel_index;
|
|
static atomic_t channel_count = ATOMIC_INIT(0);
|
|
|
|
/* Get the PPP protocol number from a skb */
|
|
#define PPP_PROTO(skb) (((skb)->data[0] << 8) + (skb)->data[1])
|
|
|
|
/* 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 ppp_file *pf, struct file *file,
|
|
unsigned int cmd, unsigned long arg);
|
|
static void ppp_xmit_process(struct ppp *ppp);
|
|
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 struct ppp *ppp_create_interface(int unit, int *retp);
|
|
static void init_ppp_file(struct ppp_file *pf, int kind);
|
|
static void ppp_shutdown_interface(struct ppp *ppp);
|
|
static void ppp_destroy_interface(struct ppp *ppp);
|
|
static struct ppp *ppp_find_unit(int unit);
|
|
static struct channel *ppp_find_channel(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 struct class *ppp_class;
|
|
|
|
/* 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 (!capable(CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
return 0;
|
|
}
|
|
|
|
static int ppp_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct ppp_file *pf = file->private_data;
|
|
struct ppp *ppp;
|
|
|
|
if (pf != 0) {
|
|
file->private_data = NULL;
|
|
if (pf->kind == INTERFACE) {
|
|
ppp = PF_TO_PPP(pf);
|
|
if (file == ppp->owner)
|
|
ppp_shutdown_interface(ppp);
|
|
}
|
|
if (atomic_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;
|
|
|
|
ret = count;
|
|
|
|
if (pf == 0)
|
|
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);
|
|
if (ppp->n_channels == 0
|
|
&& (ppp->flags & SC_LOOP_TRAFFIC) == 0)
|
|
break;
|
|
}
|
|
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 == 0)
|
|
goto out;
|
|
|
|
ret = -EOVERFLOW;
|
|
if (skb->len > count)
|
|
goto outf;
|
|
ret = -EFAULT;
|
|
if (copy_to_user(buf, skb->data, 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 == 0)
|
|
return -ENXIO;
|
|
ret = -ENOMEM;
|
|
skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL);
|
|
if (skb == 0)
|
|
goto out;
|
|
skb_reserve(skb, pf->hdrlen);
|
|
ret = -EFAULT;
|
|
if (copy_from_user(skb_put(skb, count), buf, count)) {
|
|
kfree_skb(skb);
|
|
goto out;
|
|
}
|
|
|
|
skb_queue_tail(&pf->xq, skb);
|
|
|
|
switch (pf->kind) {
|
|
case INTERFACE:
|
|
ppp_xmit_process(PF_TO_PPP(pf));
|
|
break;
|
|
case CHANNEL:
|
|
ppp_channel_push(PF_TO_CHANNEL(pf));
|
|
break;
|
|
}
|
|
|
|
ret = count;
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/* No kernel lock - fine */
|
|
static unsigned int ppp_poll(struct file *file, poll_table *wait)
|
|
{
|
|
struct ppp_file *pf = file->private_data;
|
|
unsigned int mask;
|
|
|
|
if (pf == 0)
|
|
return 0;
|
|
poll_wait(file, &pf->rwait, wait);
|
|
mask = POLLOUT | POLLWRNORM;
|
|
if (skb_peek(&pf->rq) != 0)
|
|
mask |= POLLIN | POLLRDNORM;
|
|
if (pf->dead)
|
|
mask |= POLLHUP;
|
|
else if (pf->kind == INTERFACE) {
|
|
/* see comment in ppp_read */
|
|
struct ppp *ppp = PF_TO_PPP(pf);
|
|
if (ppp->n_channels == 0
|
|
&& (ppp->flags & SC_LOOP_TRAFFIC) == 0)
|
|
mask |= POLLIN | POLLRDNORM;
|
|
}
|
|
|
|
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, err;
|
|
|
|
if (copy_from_user(&uprog, arg, sizeof(uprog)))
|
|
return -EFAULT;
|
|
|
|
if (uprog.len > BPF_MAXINSNS)
|
|
return -EINVAL;
|
|
|
|
if (!uprog.len) {
|
|
*p = NULL;
|
|
return 0;
|
|
}
|
|
|
|
len = uprog.len * sizeof(struct sock_filter);
|
|
code = kmalloc(len, GFP_KERNEL);
|
|
if (code == NULL)
|
|
return -ENOMEM;
|
|
|
|
if (copy_from_user(code, uprog.filter, len)) {
|
|
kfree(code);
|
|
return -EFAULT;
|
|
}
|
|
|
|
err = sk_chk_filter(code, uprog.len);
|
|
if (err) {
|
|
kfree(code);
|
|
return err;
|
|
}
|
|
|
|
*p = code;
|
|
return uprog.len;
|
|
}
|
|
#endif /* CONFIG_PPP_FILTER */
|
|
|
|
static int ppp_ioctl(struct inode *inode, struct file *file,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct ppp_file *pf = file->private_data;
|
|
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;
|
|
|
|
if (pf == 0)
|
|
return ppp_unattached_ioctl(pf, file, cmd, arg);
|
|
|
|
if (cmd == PPPIOCDETACH) {
|
|
/*
|
|
* We have to be careful here... if the file descriptor
|
|
* has been dup'd, we could have another process in the
|
|
* middle of a poll using the same file *, so we had
|
|
* better not free the interface data structures -
|
|
* instead we fail the ioctl. Even in this case, we
|
|
* shut down the interface if we are the owner of it.
|
|
* Actually, we should get rid of PPPIOCDETACH, userland
|
|
* (i.e. pppd) could achieve the same effect by closing
|
|
* this fd and reopening /dev/ppp.
|
|
*/
|
|
err = -EINVAL;
|
|
if (pf->kind == INTERFACE) {
|
|
ppp = PF_TO_PPP(pf);
|
|
if (file == ppp->owner)
|
|
ppp_shutdown_interface(ppp);
|
|
}
|
|
if (atomic_read(&file->f_count) <= 2) {
|
|
ppp_release(inode, file);
|
|
err = 0;
|
|
} else
|
|
printk(KERN_DEBUG "PPPIOCDETACH file->f_count=%d\n",
|
|
atomic_read(&file->f_count));
|
|
return err;
|
|
}
|
|
|
|
if (pf->kind == CHANNEL) {
|
|
struct channel *pch = PF_TO_CHANNEL(pf);
|
|
struct ppp_channel *chan;
|
|
|
|
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);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
if (pf->kind != INTERFACE) {
|
|
/* can't happen */
|
|
printk(KERN_ERR "PPP: not interface or channel??\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
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;
|
|
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 (vj == 0) {
|
|
printk(KERN_ERR "PPP: no memory (VJ compressor)\n");
|
|
err = -ENOMEM;
|
|
break;
|
|
}
|
|
ppp_lock(ppp);
|
|
if (ppp->vj != 0)
|
|
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) {
|
|
ppp_lock(ppp);
|
|
kfree(ppp->pass_filter);
|
|
ppp->pass_filter = code;
|
|
ppp->pass_len = err;
|
|
ppp_unlock(ppp);
|
|
err = 0;
|
|
}
|
|
break;
|
|
}
|
|
case PPPIOCSACTIVE:
|
|
{
|
|
struct sock_filter *code;
|
|
err = get_filter(argp, &code);
|
|
if (err >= 0) {
|
|
ppp_lock(ppp);
|
|
kfree(ppp->active_filter);
|
|
ppp->active_filter = code;
|
|
ppp->active_len = err;
|
|
ppp_unlock(ppp);
|
|
err = 0;
|
|
}
|
|
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;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
int unit, err = -EFAULT;
|
|
struct ppp *ppp;
|
|
struct channel *chan;
|
|
int __user *p = (int __user *)arg;
|
|
|
|
switch (cmd) {
|
|
case PPPIOCNEWUNIT:
|
|
/* Create a new ppp unit */
|
|
if (get_user(unit, p))
|
|
break;
|
|
ppp = ppp_create_interface(unit, &err);
|
|
if (ppp == 0)
|
|
break;
|
|
file->private_data = &ppp->file;
|
|
ppp->owner = file;
|
|
err = -EFAULT;
|
|
if (put_user(ppp->file.index, p))
|
|
break;
|
|
err = 0;
|
|
break;
|
|
|
|
case PPPIOCATTACH:
|
|
/* Attach to an existing ppp unit */
|
|
if (get_user(unit, p))
|
|
break;
|
|
down(&all_ppp_sem);
|
|
err = -ENXIO;
|
|
ppp = ppp_find_unit(unit);
|
|
if (ppp != 0) {
|
|
atomic_inc(&ppp->file.refcnt);
|
|
file->private_data = &ppp->file;
|
|
err = 0;
|
|
}
|
|
up(&all_ppp_sem);
|
|
break;
|
|
|
|
case PPPIOCATTCHAN:
|
|
if (get_user(unit, p))
|
|
break;
|
|
spin_lock_bh(&all_channels_lock);
|
|
err = -ENXIO;
|
|
chan = ppp_find_channel(unit);
|
|
if (chan != 0) {
|
|
atomic_inc(&chan->file.refcnt);
|
|
file->private_data = &chan->file;
|
|
err = 0;
|
|
}
|
|
spin_unlock_bh(&all_channels_lock);
|
|
break;
|
|
|
|
default:
|
|
err = -ENOTTY;
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static struct file_operations ppp_device_fops = {
|
|
.owner = THIS_MODULE,
|
|
.read = ppp_read,
|
|
.write = ppp_write,
|
|
.poll = ppp_poll,
|
|
.ioctl = ppp_ioctl,
|
|
.open = ppp_open,
|
|
.release = ppp_release
|
|
};
|
|
|
|
#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;
|
|
|
|
printk(KERN_INFO "PPP generic driver version " PPP_VERSION "\n");
|
|
err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops);
|
|
if (!err) {
|
|
ppp_class = class_create(THIS_MODULE, "ppp");
|
|
if (IS_ERR(ppp_class)) {
|
|
err = PTR_ERR(ppp_class);
|
|
goto out_chrdev;
|
|
}
|
|
class_device_create(ppp_class, MKDEV(PPP_MAJOR, 0), NULL, "ppp");
|
|
err = devfs_mk_cdev(MKDEV(PPP_MAJOR, 0),
|
|
S_IFCHR|S_IRUSR|S_IWUSR, "ppp");
|
|
if (err)
|
|
goto out_class;
|
|
}
|
|
|
|
out:
|
|
if (err)
|
|
printk(KERN_ERR "failed to register PPP device (%d)\n", err);
|
|
return err;
|
|
|
|
out_class:
|
|
class_device_destroy(ppp_class, MKDEV(PPP_MAJOR,0));
|
|
class_destroy(ppp_class);
|
|
out_chrdev:
|
|
unregister_chrdev(PPP_MAJOR, "ppp");
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Network interface unit routines.
|
|
*/
|
|
static int
|
|
ppp_start_xmit(struct sk_buff *skb, struct net_device *dev)
|
|
{
|
|
struct ppp *ppp = (struct ppp *) dev->priv;
|
|
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_headroom(skb) < PPP_HDRLEN) {
|
|
struct sk_buff *ns;
|
|
|
|
ns = alloc_skb(skb->len + dev->hard_header_len, GFP_ATOMIC);
|
|
if (ns == 0)
|
|
goto outf;
|
|
skb_reserve(ns, dev->hard_header_len);
|
|
skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len);
|
|
kfree_skb(skb);
|
|
skb = ns;
|
|
}
|
|
pp = skb_push(skb, 2);
|
|
proto = npindex_to_proto[npi];
|
|
pp[0] = proto >> 8;
|
|
pp[1] = proto;
|
|
|
|
netif_stop_queue(dev);
|
|
skb_queue_tail(&ppp->file.xq, skb);
|
|
ppp_xmit_process(ppp);
|
|
return 0;
|
|
|
|
outf:
|
|
kfree_skb(skb);
|
|
++ppp->stats.tx_dropped;
|
|
return 0;
|
|
}
|
|
|
|
static struct net_device_stats *
|
|
ppp_net_stats(struct net_device *dev)
|
|
{
|
|
struct ppp *ppp = (struct ppp *) dev->priv;
|
|
|
|
return &ppp->stats;
|
|
}
|
|
|
|
static int
|
|
ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
|
|
{
|
|
struct ppp *ppp = dev->priv;
|
|
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 != 0)
|
|
ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c);
|
|
if (ppp->rc_state != 0)
|
|
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_setup(struct net_device *dev)
|
|
{
|
|
dev->hard_header_len = PPP_HDRLEN;
|
|
dev->mtu = PPP_MTU;
|
|
dev->addr_len = 0;
|
|
dev->tx_queue_len = 3;
|
|
dev->type = ARPHRD_PPP;
|
|
dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
|
|
}
|
|
|
|
/*
|
|
* 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->dev != 0) {
|
|
ppp_push(ppp);
|
|
while (ppp->xmit_pending == 0
|
|
&& (skb = skb_dequeue(&ppp->file.xq)) != 0)
|
|
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 == 0 && skb_peek(&ppp->file.xq) == 0)
|
|
netif_wake_queue(ppp->dev);
|
|
}
|
|
ppp_xmit_unlock(ppp);
|
|
}
|
|
|
|
/*
|
|
* 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 */
|
|
*skb_push(skb, 2) = 1;
|
|
if (ppp->pass_filter
|
|
&& sk_run_filter(skb, ppp->pass_filter,
|
|
ppp->pass_len) == 0) {
|
|
if (ppp->debug & 1)
|
|
printk(KERN_DEBUG "PPP: outbound frame not passed\n");
|
|
kfree_skb(skb);
|
|
return;
|
|
}
|
|
/* if this packet passes the active filter, record the time */
|
|
if (!(ppp->active_filter
|
|
&& sk_run_filter(skb, ppp->active_filter,
|
|
ppp->active_len) == 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->stats.tx_packets;
|
|
ppp->stats.tx_bytes += skb->len - 2;
|
|
|
|
switch (proto) {
|
|
case PPP_IP:
|
|
if (ppp->vj == 0 || (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 == 0) {
|
|
printk(KERN_ERR "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 */
|
|
kfree_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];
|
|
}
|
|
kfree_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 != 0
|
|
&& proto != PPP_LCP && proto != PPP_CCP) {
|
|
new_skb = alloc_skb(ppp->dev->mtu + ppp->dev->hard_header_len,
|
|
GFP_ATOMIC);
|
|
if (new_skb == 0) {
|
|
printk(KERN_ERR "PPP: no memory (comp pkt)\n");
|
|
goto drop;
|
|
}
|
|
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,
|
|
ppp->dev->mtu + PPP_HDRLEN);
|
|
if (len > 0 && (ppp->flags & SC_CCP_UP)) {
|
|
kfree_skb(skb);
|
|
skb = new_skb;
|
|
skb_put(skb, len);
|
|
skb_pull(skb, 2); /* pull off A/C bytes */
|
|
} else {
|
|
/* didn't compress, or CCP not up yet */
|
|
kfree_skb(new_skb);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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->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 == 0)
|
|
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_bh(&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_bh(&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
|
|
/*
|
|
* 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, fragsize;
|
|
int i, bits, hdrlen, mtu;
|
|
int flen;
|
|
int navail, nfree;
|
|
int nbigger;
|
|
unsigned char *p, *q;
|
|
struct list_head *list;
|
|
struct channel *pch;
|
|
struct sk_buff *frag;
|
|
struct ppp_channel *chan;
|
|
|
|
nfree = 0; /* # channels which have no packet already queued */
|
|
navail = 0; /* total # of usable channels (not deregistered) */
|
|
hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
|
|
i = 0;
|
|
list_for_each_entry(pch, &ppp->channels, clist) {
|
|
navail += pch->avail = (pch->chan != NULL);
|
|
if (pch->avail) {
|
|
if (skb_queue_empty(&pch->file.xq) ||
|
|
!pch->had_frag) {
|
|
pch->avail = 2;
|
|
++nfree;
|
|
}
|
|
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 (XXX this should be optional) */
|
|
p = skb->data;
|
|
len = skb->len;
|
|
if (*p == 0) {
|
|
++p;
|
|
--len;
|
|
}
|
|
|
|
/*
|
|
* Decide on fragment size.
|
|
* We create a fragment for each free channel regardless of
|
|
* how small they are (i.e. even 0 length) in order to minimize
|
|
* the time that it will take to detect when a channel drops
|
|
* a fragment.
|
|
*/
|
|
fragsize = len;
|
|
if (nfree > 1)
|
|
fragsize = ROUNDUP(fragsize, nfree);
|
|
/* nbigger channels get fragsize bytes, the rest get fragsize-1,
|
|
except if nbigger==0, then they all get fragsize. */
|
|
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 (nfree > 0 || 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 {
|
|
--nfree;
|
|
pch->avail = 1;
|
|
}
|
|
|
|
/* check the channel's mtu and whether it is still attached. */
|
|
spin_lock_bh(&pch->downl);
|
|
if (pch->chan == NULL) {
|
|
/* can't use this channel, it's being deregistered */
|
|
spin_unlock_bh(&pch->downl);
|
|
pch->avail = 0;
|
|
if (--navail == 0)
|
|
break;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Create a fragment for this channel of
|
|
* min(max(mtu+2-hdrlen, 4), fragsize, len) bytes.
|
|
* If mtu+2-hdrlen < 4, that is a ridiculously small
|
|
* MTU, so we use mtu = 2 + hdrlen.
|
|
*/
|
|
if (fragsize > len)
|
|
fragsize = len;
|
|
flen = fragsize;
|
|
mtu = pch->chan->mtu + 2 - hdrlen;
|
|
if (mtu < 4)
|
|
mtu = 4;
|
|
if (flen > mtu)
|
|
flen = mtu;
|
|
if (flen == len && nfree == 0)
|
|
bits |= E;
|
|
frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
|
|
if (frag == 0)
|
|
goto noskb;
|
|
q = skb_put(frag, flen + hdrlen);
|
|
|
|
/* make the MP header */
|
|
q[0] = PPP_MP >> 8;
|
|
q[1] = PPP_MP;
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* Copy the data in.
|
|
* Unfortunately there is a bug in older versions of
|
|
* the Linux PPP multilink reconstruction code where it
|
|
* drops 0-length fragments. Therefore we make sure the
|
|
* fragment has at least one byte of data. Any bytes
|
|
* we add in this situation will end up as padding on the
|
|
* end of the reconstructed packet.
|
|
*/
|
|
if (flen == 0)
|
|
*skb_put(frag, 1) = 0;
|
|
else
|
|
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_bh(&pch->downl);
|
|
|
|
if (--nbigger == 0 && fragsize > 0)
|
|
--fragsize;
|
|
}
|
|
ppp->nxchan = i;
|
|
|
|
return 1;
|
|
|
|
noskb:
|
|
spin_unlock_bh(&pch->downl);
|
|
if (ppp->debug & 1)
|
|
printk(KERN_ERR "PPP: no memory (fragment)\n");
|
|
++ppp->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_bh(&pch->downl);
|
|
if (pch->chan != 0) {
|
|
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_bh(&pch->downl);
|
|
/* see if there is anything from the attached unit to be sent */
|
|
if (skb_queue_empty(&pch->file.xq)) {
|
|
read_lock_bh(&pch->upl);
|
|
ppp = pch->ppp;
|
|
if (ppp != 0)
|
|
ppp_xmit_process(ppp);
|
|
read_unlock_bh(&pch->upl);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Receive-side routines.
|
|
*/
|
|
|
|
/* misuse a few fields of the skb for MP reconstruction */
|
|
#define sequence priority
|
|
#define BEbits cb[0]
|
|
|
|
static inline void
|
|
ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
|
|
{
|
|
ppp_recv_lock(ppp);
|
|
/* ppp->dev == 0 means interface is closing down */
|
|
if (ppp->dev != 0)
|
|
ppp_receive_frame(ppp, skb, pch);
|
|
else
|
|
kfree_skb(skb);
|
|
ppp_recv_unlock(ppp);
|
|
}
|
|
|
|
void
|
|
ppp_input(struct ppp_channel *chan, struct sk_buff *skb)
|
|
{
|
|
struct channel *pch = chan->ppp;
|
|
int proto;
|
|
|
|
if (pch == 0 || skb->len == 0) {
|
|
kfree_skb(skb);
|
|
return;
|
|
}
|
|
|
|
proto = PPP_PROTO(skb);
|
|
read_lock_bh(&pch->upl);
|
|
if (pch->ppp == 0 || 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)) != 0)
|
|
kfree_skb(skb);
|
|
wake_up_interruptible(&pch->file.rwait);
|
|
} else {
|
|
ppp_do_recv(pch->ppp, skb, pch);
|
|
}
|
|
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 == 0)
|
|
return;
|
|
|
|
read_lock_bh(&pch->upl);
|
|
if (pch->ppp != 0) {
|
|
skb = alloc_skb(0, GFP_ATOMIC);
|
|
if (skb != 0) {
|
|
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)
|
|
{
|
|
if (skb->len >= 2) {
|
|
#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);
|
|
return;
|
|
}
|
|
|
|
if (skb->len > 0)
|
|
/* note: a 0-length skb is used as an error indication */
|
|
++ppp->stats.rx_length_errors;
|
|
|
|
kfree_skb(skb);
|
|
ppp_receive_error(ppp);
|
|
}
|
|
|
|
static void
|
|
ppp_receive_error(struct ppp *ppp)
|
|
{
|
|
++ppp->stats.rx_errors;
|
|
if (ppp->vj != 0)
|
|
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 != 0 && (ppp->rstate & SC_DECOMP_RUN)
|
|
&& (ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0)
|
|
skb = ppp_decompress_frame(ppp, skb);
|
|
|
|
proto = PPP_PROTO(skb);
|
|
switch (proto) {
|
|
case PPP_VJC_COMP:
|
|
/* decompress VJ compressed packets */
|
|
if (ppp->vj == 0 || (ppp->flags & SC_REJ_COMP_TCP))
|
|
goto err;
|
|
|
|
if (skb_tailroom(skb) < 124) {
|
|
/* copy to a new sk_buff with more tailroom */
|
|
ns = dev_alloc_skb(skb->len + 128);
|
|
if (ns == 0) {
|
|
printk(KERN_ERR"PPP: no memory (VJ decomp)\n");
|
|
goto err;
|
|
}
|
|
skb_reserve(ns, 2);
|
|
skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len);
|
|
kfree_skb(skb);
|
|
skb = ns;
|
|
}
|
|
else if (!pskb_may_pull(skb, skb->len))
|
|
goto err;
|
|
|
|
len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2);
|
|
if (len <= 0) {
|
|
printk(KERN_DEBUG "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 == 0 || (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) {
|
|
printk(KERN_ERR "PPP: VJ uncompressed error\n");
|
|
goto err;
|
|
}
|
|
proto = PPP_IP;
|
|
break;
|
|
|
|
case PPP_CCP:
|
|
ppp_ccp_peek(ppp, skb, 1);
|
|
break;
|
|
}
|
|
|
|
++ppp->stats.rx_packets;
|
|
ppp->stats.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)) != 0)
|
|
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 */
|
|
*skb_push(skb, 2) = 0;
|
|
if (ppp->pass_filter
|
|
&& sk_run_filter(skb, ppp->pass_filter,
|
|
ppp->pass_len) == 0) {
|
|
if (ppp->debug & 1)
|
|
printk(KERN_DEBUG "PPP: inbound frame not passed\n");
|
|
kfree_skb(skb);
|
|
return;
|
|
}
|
|
if (!(ppp->active_filter
|
|
&& sk_run_filter(skb, ppp->active_filter,
|
|
ppp->active_len) == 0))
|
|
ppp->last_recv = jiffies;
|
|
skb_pull(skb, 2);
|
|
#else
|
|
ppp->last_recv = jiffies;
|
|
#endif /* CONFIG_PPP_FILTER */
|
|
|
|
if ((ppp->dev->flags & IFF_UP) == 0
|
|
|| ppp->npmode[npi] != NPMODE_PASS) {
|
|
kfree_skb(skb);
|
|
} else {
|
|
skb_pull(skb, 2); /* chop off protocol */
|
|
skb->dev = ppp->dev;
|
|
skb->protocol = htons(npindex_to_ethertype[npi]);
|
|
skb->mac.raw = skb->data;
|
|
netif_rx(skb);
|
|
ppp->dev->last_rx = jiffies;
|
|
}
|
|
}
|
|
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) {
|
|
ns = dev_alloc_skb(ppp->mru + PPP_HDRLEN);
|
|
if (ns == 0) {
|
|
printk(KERN_ERR "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, ppp->mru + PPP_HDRLEN);
|
|
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;
|
|
}
|
|
|
|
kfree_skb(skb);
|
|
skb = ns;
|
|
skb_put(skb, len);
|
|
skb_pull(skb, 2); /* pull off the A/C bytes */
|
|
|
|
} 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) || 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;
|
|
}
|
|
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.
|
|
*/
|
|
if ((skb->BEbits & B) && (skb->data[0] & 1))
|
|
*skb_push(skb, 1) = 0;
|
|
|
|
/*
|
|
* 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 */
|
|
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->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
|
|
&& seq_before(ppp->minseq, ppp->mrq.next->sequence))
|
|
ppp->minseq = ppp->mrq.next->sequence;
|
|
|
|
/* Pull completed packets off the queue and receive them. */
|
|
while ((skb = ppp_mp_reconstruct(ppp)) != 0)
|
|
ppp_receive_nonmp_frame(ppp, skb);
|
|
|
|
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 = skb->sequence;
|
|
|
|
/* N.B. we don't need to lock the list lock because we have the
|
|
ppp unit receive-side lock. */
|
|
for (p = list->next; p != (struct sk_buff *)list; p = p->next)
|
|
if (seq_before(seq, p->sequence))
|
|
break;
|
|
__skb_insert(skb, p->prev, p, list);
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
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, *next;
|
|
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;
|
|
for (p = head; p != (struct sk_buff *) list; p = next) {
|
|
next = p->next;
|
|
if (seq_before(p->sequence, seq)) {
|
|
/* this can't happen, anyway ignore the skb */
|
|
printk(KERN_ERR "ppp_mp_reconstruct bad seq %u < %u\n",
|
|
p->sequence, seq);
|
|
head = next;
|
|
continue;
|
|
}
|
|
if (p->sequence != seq) {
|
|
/* 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;
|
|
seq = seq_before(minseq, p->sequence)?
|
|
minseq + 1: p->sequence;
|
|
next = p;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* 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 (p->BEbits & B) {
|
|
head = p;
|
|
lost = 0;
|
|
len = 0;
|
|
}
|
|
|
|
len += p->len;
|
|
|
|
/* Got a complete packet yet? */
|
|
if (lost == 0 && (p->BEbits & E) && (head->BEbits & B)) {
|
|
if (len > ppp->mrru + 2) {
|
|
++ppp->stats.rx_length_errors;
|
|
printk(KERN_DEBUG "PPP: reconstructed packet"
|
|
" is too long (%d)\n", len);
|
|
} else if (p == head) {
|
|
/* fragment is complete packet - reuse skb */
|
|
tail = p;
|
|
skb = skb_get(p);
|
|
break;
|
|
} else if ((skb = dev_alloc_skb(len)) == NULL) {
|
|
++ppp->stats.rx_missed_errors;
|
|
printk(KERN_DEBUG "PPP: no memory for "
|
|
"reconstructed packet");
|
|
} 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 (p->BEbits & E)
|
|
head = next;
|
|
|
|
++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 (head->sequence != ppp->nextseq) {
|
|
if (ppp->debug & 1)
|
|
printk(KERN_DEBUG " missed pkts %u..%u\n",
|
|
ppp->nextseq, head->sequence-1);
|
|
++ppp->stats.rx_dropped;
|
|
ppp_receive_error(ppp);
|
|
}
|
|
|
|
if (head != tail)
|
|
/* copy to a single skb */
|
|
for (p = head; p != tail->next; p = p->next)
|
|
skb_copy_bits(p, 0, skb_put(skb, p->len), p->len);
|
|
ppp->nextseq = tail->sequence + 1;
|
|
head = tail->next;
|
|
}
|
|
|
|
/* Discard all the skbuffs that we have copied the data out of
|
|
or that we can't use. */
|
|
while ((p = list->next) != head) {
|
|
__skb_unlink(p, list);
|
|
kfree_skb(p);
|
|
}
|
|
|
|
return skb;
|
|
}
|
|
#endif /* CONFIG_PPP_MULTILINK */
|
|
|
|
/*
|
|
* Channel interface.
|
|
*/
|
|
|
|
/*
|
|
* Create a new, unattached ppp channel.
|
|
*/
|
|
int
|
|
ppp_register_channel(struct ppp_channel *chan)
|
|
{
|
|
struct channel *pch;
|
|
|
|
pch = kmalloc(sizeof(struct channel), GFP_KERNEL);
|
|
if (pch == 0)
|
|
return -ENOMEM;
|
|
memset(pch, 0, sizeof(struct channel));
|
|
pch->ppp = NULL;
|
|
pch->chan = chan;
|
|
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(&all_channels_lock);
|
|
pch->file.index = ++last_channel_index;
|
|
list_add(&pch->list, &new_channels);
|
|
atomic_inc(&channel_count);
|
|
spin_unlock_bh(&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 != 0)
|
|
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 != 0) {
|
|
read_lock_bh(&pch->upl);
|
|
if (pch->ppp != 0)
|
|
unit = pch->ppp->file.index;
|
|
read_unlock_bh(&pch->upl);
|
|
}
|
|
return unit;
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
|
|
if (pch == 0)
|
|
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);
|
|
spin_lock_bh(&all_channels_lock);
|
|
list_del(&pch->list);
|
|
spin_unlock_bh(&all_channels_lock);
|
|
pch->file.dead = 1;
|
|
wake_up_interruptible(&pch->file.rwait);
|
|
if (atomic_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 == 0)
|
|
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))
|
|
|| (data.length <= CCP_MAX_OPTION_LENGTH
|
|
&& copy_from_user(ccp_option, (void __user *) data.ptr, data.length)))
|
|
goto out;
|
|
err = -EINVAL;
|
|
if (data.length > CCP_MAX_OPTION_LENGTH
|
|
|| ccp_option[1] < 2 || ccp_option[1] > data.length)
|
|
goto out;
|
|
|
|
cp = find_compressor(ccp_option[0]);
|
|
#ifdef CONFIG_KMOD
|
|
if (cp == 0) {
|
|
request_module("ppp-compress-%d", ccp_option[0]);
|
|
cp = find_compressor(ccp_option[0]);
|
|
}
|
|
#endif /* CONFIG_KMOD */
|
|
if (cp == 0)
|
|
goto out;
|
|
|
|
err = -ENOBUFS;
|
|
if (data.transmit) {
|
|
state = cp->comp_alloc(ccp_option, data.length);
|
|
if (state != 0) {
|
|
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 != 0) {
|
|
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 != 0) {
|
|
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 != 0) {
|
|
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 == 0)
|
|
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 == 0)
|
|
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) != 0)
|
|
goto out;
|
|
ret = -ENOMEM;
|
|
ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC);
|
|
if (ce == 0)
|
|
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 != 0 && 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 != 0) {
|
|
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->stats.rx_packets;
|
|
st->p.ppp_ierrors = ppp->stats.rx_errors;
|
|
st->p.ppp_ibytes = ppp->stats.rx_bytes;
|
|
st->p.ppp_opackets = ppp->stats.tx_packets;
|
|
st->p.ppp_oerrors = ppp->stats.tx_errors;
|
|
st->p.ppp_obytes = ppp->stats.tx_bytes;
|
|
if (vj == 0)
|
|
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 struct ppp *
|
|
ppp_create_interface(int unit, int *retp)
|
|
{
|
|
struct ppp *ppp;
|
|
struct net_device *dev = NULL;
|
|
int ret = -ENOMEM;
|
|
int i;
|
|
|
|
ppp = kmalloc(sizeof(struct ppp), GFP_KERNEL);
|
|
if (!ppp)
|
|
goto out;
|
|
dev = alloc_netdev(0, "", ppp_setup);
|
|
if (!dev)
|
|
goto out1;
|
|
memset(ppp, 0, sizeof(struct ppp));
|
|
|
|
ppp->mru = PPP_MRU;
|
|
init_ppp_file(&ppp->file, INTERFACE);
|
|
ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */
|
|
for (i = 0; i < NUM_NP; ++i)
|
|
ppp->npmode[i] = NPMODE_PASS;
|
|
INIT_LIST_HEAD(&ppp->channels);
|
|
spin_lock_init(&ppp->rlock);
|
|
spin_lock_init(&ppp->wlock);
|
|
#ifdef CONFIG_PPP_MULTILINK
|
|
ppp->minseq = -1;
|
|
skb_queue_head_init(&ppp->mrq);
|
|
#endif /* CONFIG_PPP_MULTILINK */
|
|
ppp->dev = dev;
|
|
dev->priv = ppp;
|
|
|
|
dev->hard_start_xmit = ppp_start_xmit;
|
|
dev->get_stats = ppp_net_stats;
|
|
dev->do_ioctl = ppp_net_ioctl;
|
|
|
|
ret = -EEXIST;
|
|
down(&all_ppp_sem);
|
|
if (unit < 0)
|
|
unit = cardmap_find_first_free(all_ppp_units);
|
|
else if (cardmap_get(all_ppp_units, unit) != NULL)
|
|
goto out2; /* unit already exists */
|
|
|
|
/* Initialize the new ppp unit */
|
|
ppp->file.index = unit;
|
|
sprintf(dev->name, "ppp%d", unit);
|
|
|
|
ret = register_netdev(dev);
|
|
if (ret != 0) {
|
|
printk(KERN_ERR "PPP: couldn't register device %s (%d)\n",
|
|
dev->name, ret);
|
|
goto out2;
|
|
}
|
|
|
|
atomic_inc(&ppp_unit_count);
|
|
cardmap_set(&all_ppp_units, unit, ppp);
|
|
up(&all_ppp_sem);
|
|
*retp = 0;
|
|
return ppp;
|
|
|
|
out2:
|
|
up(&all_ppp_sem);
|
|
free_netdev(dev);
|
|
out1:
|
|
kfree(ppp);
|
|
out:
|
|
*retp = ret;
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
atomic_set(&pf->refcnt, 1);
|
|
init_waitqueue_head(&pf->rwait);
|
|
}
|
|
|
|
/*
|
|
* Take down a ppp interface unit - called when the owning file
|
|
* (the one that created the unit) is closed or detached.
|
|
*/
|
|
static void ppp_shutdown_interface(struct ppp *ppp)
|
|
{
|
|
struct net_device *dev;
|
|
|
|
down(&all_ppp_sem);
|
|
ppp_lock(ppp);
|
|
dev = ppp->dev;
|
|
ppp->dev = NULL;
|
|
ppp_unlock(ppp);
|
|
/* This will call dev_close() for us. */
|
|
if (dev) {
|
|
unregister_netdev(dev);
|
|
free_netdev(dev);
|
|
}
|
|
cardmap_set(&all_ppp_units, ppp->file.index, NULL);
|
|
ppp->file.dead = 1;
|
|
ppp->owner = NULL;
|
|
wake_up_interruptible(&ppp->file.rwait);
|
|
up(&all_ppp_sem);
|
|
}
|
|
|
|
/*
|
|
* 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" */
|
|
printk(KERN_ERR "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
|
|
kfree(ppp->pass_filter);
|
|
ppp->pass_filter = NULL;
|
|
kfree(ppp->active_filter);
|
|
ppp->active_filter = NULL;
|
|
#endif /* CONFIG_PPP_FILTER */
|
|
|
|
kfree(ppp);
|
|
}
|
|
|
|
/*
|
|
* Locate an existing ppp unit.
|
|
* The caller should have locked the all_ppp_sem.
|
|
*/
|
|
static struct ppp *
|
|
ppp_find_unit(int unit)
|
|
{
|
|
return cardmap_get(all_ppp_units, 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(int unit)
|
|
{
|
|
struct channel *pch;
|
|
|
|
list_for_each_entry(pch, &new_channels, list) {
|
|
if (pch->file.index == unit) {
|
|
list_del(&pch->list);
|
|
list_add(&pch->list, &all_channels);
|
|
return pch;
|
|
}
|
|
}
|
|
list_for_each_entry(pch, &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;
|
|
int ret = -ENXIO;
|
|
int hdrlen;
|
|
|
|
down(&all_ppp_sem);
|
|
ppp = ppp_find_unit(unit);
|
|
if (ppp == 0)
|
|
goto out;
|
|
write_lock_bh(&pch->upl);
|
|
ret = -EINVAL;
|
|
if (pch->ppp != 0)
|
|
goto outl;
|
|
|
|
ppp_lock(ppp);
|
|
if (pch->file.hdrlen > ppp->file.hdrlen)
|
|
ppp->file.hdrlen = pch->file.hdrlen;
|
|
hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */
|
|
if (ppp->dev && 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;
|
|
atomic_inc(&ppp->file.refcnt);
|
|
ppp_unlock(ppp);
|
|
ret = 0;
|
|
|
|
outl:
|
|
write_unlock_bh(&pch->upl);
|
|
out:
|
|
up(&all_ppp_sem);
|
|
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 != 0) {
|
|
/* 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 (atomic_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)
|
|
{
|
|
atomic_dec(&channel_count);
|
|
|
|
if (!pch->file.dead) {
|
|
/* "can't happen" */
|
|
printk(KERN_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))
|
|
printk(KERN_ERR "PPP: removing module but units remain!\n");
|
|
cardmap_destroy(&all_ppp_units);
|
|
if (unregister_chrdev(PPP_MAJOR, "ppp") != 0)
|
|
printk(KERN_ERR "PPP: failed to unregister PPP device\n");
|
|
devfs_remove("ppp");
|
|
class_device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0));
|
|
class_destroy(ppp_class);
|
|
}
|
|
|
|
/*
|
|
* Cardmap implementation.
|
|
*/
|
|
static void *cardmap_get(struct cardmap *map, unsigned int nr)
|
|
{
|
|
struct cardmap *p;
|
|
int i;
|
|
|
|
for (p = map; p != NULL; ) {
|
|
if ((i = nr >> p->shift) >= CARDMAP_WIDTH)
|
|
return NULL;
|
|
if (p->shift == 0)
|
|
return p->ptr[i];
|
|
nr &= ~(CARDMAP_MASK << p->shift);
|
|
p = p->ptr[i];
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static void cardmap_set(struct cardmap **pmap, unsigned int nr, void *ptr)
|
|
{
|
|
struct cardmap *p;
|
|
int i;
|
|
|
|
p = *pmap;
|
|
if (p == NULL || (nr >> p->shift) >= CARDMAP_WIDTH) {
|
|
do {
|
|
/* need a new top level */
|
|
struct cardmap *np = kmalloc(sizeof(*np), GFP_KERNEL);
|
|
memset(np, 0, sizeof(*np));
|
|
np->ptr[0] = p;
|
|
if (p != NULL) {
|
|
np->shift = p->shift + CARDMAP_ORDER;
|
|
p->parent = np;
|
|
} else
|
|
np->shift = 0;
|
|
p = np;
|
|
} while ((nr >> p->shift) >= CARDMAP_WIDTH);
|
|
*pmap = p;
|
|
}
|
|
while (p->shift > 0) {
|
|
i = (nr >> p->shift) & CARDMAP_MASK;
|
|
if (p->ptr[i] == NULL) {
|
|
struct cardmap *np = kmalloc(sizeof(*np), GFP_KERNEL);
|
|
memset(np, 0, sizeof(*np));
|
|
np->shift = p->shift - CARDMAP_ORDER;
|
|
np->parent = p;
|
|
p->ptr[i] = np;
|
|
}
|
|
if (ptr == NULL)
|
|
clear_bit(i, &p->inuse);
|
|
p = p->ptr[i];
|
|
}
|
|
i = nr & CARDMAP_MASK;
|
|
p->ptr[i] = ptr;
|
|
if (ptr != NULL)
|
|
set_bit(i, &p->inuse);
|
|
else
|
|
clear_bit(i, &p->inuse);
|
|
}
|
|
|
|
static unsigned int cardmap_find_first_free(struct cardmap *map)
|
|
{
|
|
struct cardmap *p;
|
|
unsigned int nr = 0;
|
|
int i;
|
|
|
|
if ((p = map) == NULL)
|
|
return 0;
|
|
for (;;) {
|
|
i = find_first_zero_bit(&p->inuse, CARDMAP_WIDTH);
|
|
if (i >= CARDMAP_WIDTH) {
|
|
if (p->parent == NULL)
|
|
return CARDMAP_WIDTH << p->shift;
|
|
p = p->parent;
|
|
i = (nr >> p->shift) & CARDMAP_MASK;
|
|
set_bit(i, &p->inuse);
|
|
continue;
|
|
}
|
|
nr = (nr & (~CARDMAP_MASK << p->shift)) | (i << p->shift);
|
|
if (p->shift == 0 || p->ptr[i] == NULL)
|
|
return nr;
|
|
p = p->ptr[i];
|
|
}
|
|
}
|
|
|
|
static void cardmap_destroy(struct cardmap **pmap)
|
|
{
|
|
struct cardmap *p, *np;
|
|
int i;
|
|
|
|
for (p = *pmap; p != NULL; p = np) {
|
|
if (p->shift != 0) {
|
|
for (i = 0; i < CARDMAP_WIDTH; ++i)
|
|
if (p->ptr[i] != NULL)
|
|
break;
|
|
if (i < CARDMAP_WIDTH) {
|
|
np = p->ptr[i];
|
|
p->ptr[i] = NULL;
|
|
continue;
|
|
}
|
|
}
|
|
np = p->parent;
|
|
kfree(p);
|
|
}
|
|
*pmap = NULL;
|
|
}
|
|
|
|
/* Module/initialization stuff */
|
|
|
|
module_init(ppp_init);
|
|
module_exit(ppp_cleanup);
|
|
|
|
EXPORT_SYMBOL(ppp_register_channel);
|
|
EXPORT_SYMBOL(ppp_unregister_channel);
|
|
EXPORT_SYMBOL(ppp_channel_index);
|
|
EXPORT_SYMBOL(ppp_unit_number);
|
|
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_MAJOR(PPP_MAJOR);
|
|
MODULE_ALIAS("/dev/ppp");
|