2 * Generic PPP layer for Linux.
4 * Copyright 1999-2002 Paul Mackerras.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
11 * The generic PPP layer handles the PPP network interfaces, the
12 * /dev/ppp device, packet and VJ compression, and multilink.
13 * It talks to PPP `channels' via the interface defined in
14 * include/linux/ppp_channel.h. Channels provide the basic means for
15 * sending and receiving PPP frames on some kind of communications
18 * Part of the code in this driver was inspired by the old async-only
19 * PPP driver, written by Michael Callahan and Al Longyear, and
20 * subsequently hacked by Paul Mackerras.
22 * ==FILEVERSION 20041108==
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/kmod.h>
28 #include <linux/init.h>
29 #include <linux/list.h>
30 #include <linux/idr.h>
31 #include <linux/netdevice.h>
32 #include <linux/poll.h>
33 #include <linux/ppp_defs.h>
34 #include <linux/filter.h>
35 #include <linux/if_ppp.h>
36 #include <linux/ppp_channel.h>
37 #include <linux/ppp-comp.h>
38 #include <linux/skbuff.h>
39 #include <linux/rtnetlink.h>
40 #include <linux/if_arp.h>
42 #include <linux/tcp.h>
43 #include <linux/smp_lock.h>
44 #include <linux/spinlock.h>
45 #include <linux/rwsem.h>
46 #include <linux/stddef.h>
47 #include <linux/device.h>
48 #include <linux/mutex.h>
49 #include <net/slhc_vj.h>
50 #include <asm/atomic.h>
52 #include <linux/nsproxy.h>
53 #include <net/net_namespace.h>
54 #include <net/netns/generic.h>
56 #define PPP_VERSION "2.4.2"
59 * Network protocols we support.
61 #define NP_IP 0 /* Internet Protocol V4 */
62 #define NP_IPV6 1 /* Internet Protocol V6 */
63 #define NP_IPX 2 /* IPX protocol */
64 #define NP_AT 3 /* Appletalk protocol */
65 #define NP_MPLS_UC 4 /* MPLS unicast */
66 #define NP_MPLS_MC 5 /* MPLS multicast */
67 #define NUM_NP 6 /* Number of NPs. */
69 #define MPHDRLEN 6 /* multilink protocol header length */
70 #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */
71 #define MIN_FRAG_SIZE 64
74 * An instance of /dev/ppp can be associated with either a ppp
75 * interface unit or a ppp channel. In both cases, file->private_data
76 * points to one of these.
82 struct sk_buff_head xq
; /* pppd transmit queue */
83 struct sk_buff_head rq
; /* receive queue for pppd */
84 wait_queue_head_t rwait
; /* for poll on reading /dev/ppp */
85 atomic_t refcnt
; /* # refs (incl /dev/ppp attached) */
86 int hdrlen
; /* space to leave for headers */
87 int index
; /* interface unit / channel number */
88 int dead
; /* unit/channel has been shut down */
91 #define PF_TO_X(pf, X) container_of(pf, X, file)
93 #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp)
94 #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel)
97 * Data structure describing one ppp unit.
98 * A ppp unit corresponds to a ppp network interface device
99 * and represents a multilink bundle.
100 * It can have 0 or more ppp channels connected to it.
103 struct ppp_file file
; /* stuff for read/write/poll 0 */
104 struct file
*owner
; /* file that owns this unit 48 */
105 struct list_head channels
; /* list of attached channels 4c */
106 int n_channels
; /* how many channels are attached 54 */
107 spinlock_t rlock
; /* lock for receive side 58 */
108 spinlock_t wlock
; /* lock for transmit side 5c */
109 int mru
; /* max receive unit 60 */
110 unsigned int flags
; /* control bits 64 */
111 unsigned int xstate
; /* transmit state bits 68 */
112 unsigned int rstate
; /* receive state bits 6c */
113 int debug
; /* debug flags 70 */
114 struct slcompress
*vj
; /* state for VJ header compression */
115 enum NPmode npmode
[NUM_NP
]; /* what to do with each net proto 78 */
116 struct sk_buff
*xmit_pending
; /* a packet ready to go out 88 */
117 struct compressor
*xcomp
; /* transmit packet compressor 8c */
118 void *xc_state
; /* its internal state 90 */
119 struct compressor
*rcomp
; /* receive decompressor 94 */
120 void *rc_state
; /* its internal state 98 */
121 unsigned long last_xmit
; /* jiffies when last pkt sent 9c */
122 unsigned long last_recv
; /* jiffies when last pkt rcvd a0 */
123 struct net_device
*dev
; /* network interface device a4 */
124 int closing
; /* is device closing down? a8 */
125 #ifdef CONFIG_PPP_MULTILINK
126 int nxchan
; /* next channel to send something on */
127 u32 nxseq
; /* next sequence number to send */
128 int mrru
; /* MP: max reconst. receive unit */
129 u32 nextseq
; /* MP: seq no of next packet */
130 u32 minseq
; /* MP: min of most recent seqnos */
131 struct sk_buff_head mrq
; /* MP: receive reconstruction queue */
132 #endif /* CONFIG_PPP_MULTILINK */
133 #ifdef CONFIG_PPP_FILTER
134 struct sock_filter
*pass_filter
; /* filter for packets to pass */
135 struct sock_filter
*active_filter
;/* filter for pkts to reset idle */
136 unsigned pass_len
, active_len
;
137 #endif /* CONFIG_PPP_FILTER */
138 struct net
*ppp_net
; /* the net we belong to */
142 * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
143 * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP,
145 * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR.
146 * Bits in xstate: SC_COMP_RUN
148 #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \
149 |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \
150 |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP)
153 * Private data structure for each channel.
154 * This includes the data structure used for multilink.
157 struct ppp_file file
; /* stuff for read/write/poll */
158 struct list_head list
; /* link in all/new_channels list */
159 struct ppp_channel
*chan
; /* public channel data structure */
160 struct rw_semaphore chan_sem
; /* protects `chan' during chan ioctl */
161 spinlock_t downl
; /* protects `chan', file.xq dequeue */
162 struct ppp
*ppp
; /* ppp unit we're connected to */
163 struct net
*chan_net
; /* the net channel belongs to */
164 struct list_head clist
; /* link in list of channels per unit */
165 rwlock_t upl
; /* protects `ppp' */
166 #ifdef CONFIG_PPP_MULTILINK
167 u8 avail
; /* flag used in multilink stuff */
168 u8 had_frag
; /* >= 1 fragments have been sent */
169 u32 lastseq
; /* MP: last sequence # received */
170 int speed
; /* speed of the corresponding ppp channel*/
171 #endif /* CONFIG_PPP_MULTILINK */
175 * SMP locking issues:
176 * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels
177 * list and the ppp.n_channels field, you need to take both locks
178 * before you modify them.
179 * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
183 static atomic_t ppp_unit_count
= ATOMIC_INIT(0);
184 static atomic_t channel_count
= ATOMIC_INIT(0);
186 /* per-net private data for this module */
187 static int ppp_net_id
;
189 /* units to ppp mapping */
190 struct idr units_idr
;
193 * all_ppp_mutex protects the units_idr mapping.
194 * It also ensures that finding a ppp unit in the units_idr
195 * map and updating its file.refcnt field is atomic.
197 struct mutex all_ppp_mutex
;
200 struct list_head all_channels
;
201 struct list_head new_channels
;
202 int last_channel_index
;
205 * all_channels_lock protects all_channels and
206 * last_channel_index, and the atomicity of find
207 * a channel and updating its file.refcnt field.
209 spinlock_t all_channels_lock
;
212 /* Get the PPP protocol number from a skb */
213 #define PPP_PROTO(skb) (((skb)->data[0] << 8) + (skb)->data[1])
215 /* We limit the length of ppp->file.rq to this (arbitrary) value */
216 #define PPP_MAX_RQLEN 32
219 * Maximum number of multilink fragments queued up.
220 * This has to be large enough to cope with the maximum latency of
221 * the slowest channel relative to the others. Strictly it should
222 * depend on the number of channels and their characteristics.
224 #define PPP_MP_MAX_QLEN 128
226 /* Multilink header bits. */
227 #define B 0x80 /* this fragment begins a packet */
228 #define E 0x40 /* this fragment ends a packet */
230 /* Compare multilink sequence numbers (assumed to be 32 bits wide) */
231 #define seq_before(a, b) ((s32)((a) - (b)) < 0)
232 #define seq_after(a, b) ((s32)((a) - (b)) > 0)
235 static int ppp_unattached_ioctl(struct net
*net
, struct ppp_file
*pf
,
236 struct file
*file
, unsigned int cmd
, unsigned long arg
);
237 static void ppp_xmit_process(struct ppp
*ppp
);
238 static void ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
);
239 static void ppp_push(struct ppp
*ppp
);
240 static void ppp_channel_push(struct channel
*pch
);
241 static void ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
,
242 struct channel
*pch
);
243 static void ppp_receive_error(struct ppp
*ppp
);
244 static void ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
);
245 static struct sk_buff
*ppp_decompress_frame(struct ppp
*ppp
,
246 struct sk_buff
*skb
);
247 #ifdef CONFIG_PPP_MULTILINK
248 static void ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
,
249 struct channel
*pch
);
250 static void ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
);
251 static struct sk_buff
*ppp_mp_reconstruct(struct ppp
*ppp
);
252 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
);
253 #endif /* CONFIG_PPP_MULTILINK */
254 static int ppp_set_compress(struct ppp
*ppp
, unsigned long arg
);
255 static void ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
);
256 static void ppp_ccp_closed(struct ppp
*ppp
);
257 static struct compressor
*find_compressor(int type
);
258 static void ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
);
259 static struct ppp
*ppp_create_interface(struct net
*net
, int unit
, int *retp
);
260 static void init_ppp_file(struct ppp_file
*pf
, int kind
);
261 static void ppp_shutdown_interface(struct ppp
*ppp
);
262 static void ppp_destroy_interface(struct ppp
*ppp
);
263 static struct ppp
*ppp_find_unit(struct ppp_net
*pn
, int unit
);
264 static struct channel
*ppp_find_channel(struct ppp_net
*pn
, int unit
);
265 static int ppp_connect_channel(struct channel
*pch
, int unit
);
266 static int ppp_disconnect_channel(struct channel
*pch
);
267 static void ppp_destroy_channel(struct channel
*pch
);
268 static int unit_get(struct idr
*p
, void *ptr
);
269 static int unit_set(struct idr
*p
, void *ptr
, int n
);
270 static void unit_put(struct idr
*p
, int n
);
271 static void *unit_find(struct idr
*p
, int n
);
273 static struct class *ppp_class
;
275 /* per net-namespace data */
276 static inline struct ppp_net
*ppp_pernet(struct net
*net
)
280 return net_generic(net
, ppp_net_id
);
283 /* Translates a PPP protocol number to a NP index (NP == network protocol) */
284 static inline int proto_to_npindex(int proto
)
303 /* Translates an NP index into a PPP protocol number */
304 static const int npindex_to_proto
[NUM_NP
] = {
313 /* Translates an ethertype into an NP index */
314 static inline int ethertype_to_npindex(int ethertype
)
334 /* Translates an NP index into an ethertype */
335 static const int npindex_to_ethertype
[NUM_NP
] = {
347 #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock)
348 #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock)
349 #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock)
350 #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock)
351 #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \
352 ppp_recv_lock(ppp); } while (0)
353 #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \
354 ppp_xmit_unlock(ppp); } while (0)
357 * /dev/ppp device routines.
358 * The /dev/ppp device is used by pppd to control the ppp unit.
359 * It supports the read, write, ioctl and poll functions.
360 * Open instances of /dev/ppp can be in one of three states:
361 * unattached, attached to a ppp unit, or attached to a ppp channel.
363 static int ppp_open(struct inode
*inode
, struct file
*file
)
367 * This could (should?) be enforced by the permissions on /dev/ppp.
369 if (!capable(CAP_NET_ADMIN
))
374 static int ppp_release(struct inode
*unused
, struct file
*file
)
376 struct ppp_file
*pf
= file
->private_data
;
380 file
->private_data
= NULL
;
381 if (pf
->kind
== INTERFACE
) {
383 if (file
== ppp
->owner
)
384 ppp_shutdown_interface(ppp
);
386 if (atomic_dec_and_test(&pf
->refcnt
)) {
389 ppp_destroy_interface(PF_TO_PPP(pf
));
392 ppp_destroy_channel(PF_TO_CHANNEL(pf
));
400 static ssize_t
ppp_read(struct file
*file
, char __user
*buf
,
401 size_t count
, loff_t
*ppos
)
403 struct ppp_file
*pf
= file
->private_data
;
404 DECLARE_WAITQUEUE(wait
, current
);
406 struct sk_buff
*skb
= NULL
;
412 add_wait_queue(&pf
->rwait
, &wait
);
414 set_current_state(TASK_INTERRUPTIBLE
);
415 skb
= skb_dequeue(&pf
->rq
);
421 if (pf
->kind
== INTERFACE
) {
423 * Return 0 (EOF) on an interface that has no
424 * channels connected, unless it is looping
425 * network traffic (demand mode).
427 struct ppp
*ppp
= PF_TO_PPP(pf
);
428 if (ppp
->n_channels
== 0
429 && (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0)
433 if (file
->f_flags
& O_NONBLOCK
)
436 if (signal_pending(current
))
440 set_current_state(TASK_RUNNING
);
441 remove_wait_queue(&pf
->rwait
, &wait
);
447 if (skb
->len
> count
)
450 if (copy_to_user(buf
, skb
->data
, skb
->len
))
460 static ssize_t
ppp_write(struct file
*file
, const char __user
*buf
,
461 size_t count
, loff_t
*ppos
)
463 struct ppp_file
*pf
= file
->private_data
;
470 skb
= alloc_skb(count
+ pf
->hdrlen
, GFP_KERNEL
);
473 skb_reserve(skb
, pf
->hdrlen
);
475 if (copy_from_user(skb_put(skb
, count
), buf
, count
)) {
480 skb_queue_tail(&pf
->xq
, skb
);
484 ppp_xmit_process(PF_TO_PPP(pf
));
487 ppp_channel_push(PF_TO_CHANNEL(pf
));
497 /* No kernel lock - fine */
498 static unsigned int ppp_poll(struct file
*file
, poll_table
*wait
)
500 struct ppp_file
*pf
= file
->private_data
;
505 poll_wait(file
, &pf
->rwait
, wait
);
506 mask
= POLLOUT
| POLLWRNORM
;
507 if (skb_peek(&pf
->rq
))
508 mask
|= POLLIN
| POLLRDNORM
;
511 else if (pf
->kind
== INTERFACE
) {
512 /* see comment in ppp_read */
513 struct ppp
*ppp
= PF_TO_PPP(pf
);
514 if (ppp
->n_channels
== 0
515 && (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0)
516 mask
|= POLLIN
| POLLRDNORM
;
522 #ifdef CONFIG_PPP_FILTER
523 static int get_filter(void __user
*arg
, struct sock_filter
**p
)
525 struct sock_fprog uprog
;
526 struct sock_filter
*code
= NULL
;
529 if (copy_from_user(&uprog
, arg
, sizeof(uprog
)))
537 len
= uprog
.len
* sizeof(struct sock_filter
);
538 code
= kmalloc(len
, GFP_KERNEL
);
542 if (copy_from_user(code
, uprog
.filter
, len
)) {
547 err
= sk_chk_filter(code
, uprog
.len
);
556 #endif /* CONFIG_PPP_FILTER */
558 static long ppp_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
560 struct ppp_file
*pf
= file
->private_data
;
562 int err
= -EFAULT
, val
, val2
, i
;
563 struct ppp_idle idle
;
566 struct slcompress
*vj
;
567 void __user
*argp
= (void __user
*)arg
;
568 int __user
*p
= argp
;
571 return ppp_unattached_ioctl(current
->nsproxy
->net_ns
,
574 if (cmd
== PPPIOCDETACH
) {
576 * We have to be careful here... if the file descriptor
577 * has been dup'd, we could have another process in the
578 * middle of a poll using the same file *, so we had
579 * better not free the interface data structures -
580 * instead we fail the ioctl. Even in this case, we
581 * shut down the interface if we are the owner of it.
582 * Actually, we should get rid of PPPIOCDETACH, userland
583 * (i.e. pppd) could achieve the same effect by closing
584 * this fd and reopening /dev/ppp.
588 if (pf
->kind
== INTERFACE
) {
590 if (file
== ppp
->owner
)
591 ppp_shutdown_interface(ppp
);
593 if (atomic_long_read(&file
->f_count
) <= 2) {
594 ppp_release(NULL
, file
);
597 printk(KERN_DEBUG
"PPPIOCDETACH file->f_count=%ld\n",
598 atomic_long_read(&file
->f_count
));
603 if (pf
->kind
== CHANNEL
) {
605 struct ppp_channel
*chan
;
608 pch
= PF_TO_CHANNEL(pf
);
612 if (get_user(unit
, p
))
614 err
= ppp_connect_channel(pch
, unit
);
618 err
= ppp_disconnect_channel(pch
);
622 down_read(&pch
->chan_sem
);
625 if (chan
&& chan
->ops
->ioctl
)
626 err
= chan
->ops
->ioctl(chan
, cmd
, arg
);
627 up_read(&pch
->chan_sem
);
633 if (pf
->kind
!= INTERFACE
) {
635 printk(KERN_ERR
"PPP: not interface or channel??\n");
643 if (get_user(val
, p
))
650 if (get_user(val
, p
))
653 cflags
= ppp
->flags
& ~val
;
654 ppp
->flags
= val
& SC_FLAG_BITS
;
656 if (cflags
& SC_CCP_OPEN
)
662 val
= ppp
->flags
| ppp
->xstate
| ppp
->rstate
;
663 if (put_user(val
, p
))
668 case PPPIOCSCOMPRESS
:
669 err
= ppp_set_compress(ppp
, arg
);
673 if (put_user(ppp
->file
.index
, p
))
679 if (get_user(val
, p
))
686 if (put_user(ppp
->debug
, p
))
692 idle
.xmit_idle
= (jiffies
- ppp
->last_xmit
) / HZ
;
693 idle
.recv_idle
= (jiffies
- ppp
->last_recv
) / HZ
;
694 if (copy_to_user(argp
, &idle
, sizeof(idle
)))
700 if (get_user(val
, p
))
703 if ((val
>> 16) != 0) {
707 vj
= slhc_init(val2
+1, val
+1);
709 printk(KERN_ERR
"PPP: no memory (VJ compressor)\n");
723 if (copy_from_user(&npi
, argp
, sizeof(npi
)))
725 err
= proto_to_npindex(npi
.protocol
);
729 if (cmd
== PPPIOCGNPMODE
) {
731 npi
.mode
= ppp
->npmode
[i
];
732 if (copy_to_user(argp
, &npi
, sizeof(npi
)))
735 ppp
->npmode
[i
] = npi
.mode
;
736 /* we may be able to transmit more packets now (??) */
737 netif_wake_queue(ppp
->dev
);
742 #ifdef CONFIG_PPP_FILTER
745 struct sock_filter
*code
;
746 err
= get_filter(argp
, &code
);
749 kfree(ppp
->pass_filter
);
750 ppp
->pass_filter
= code
;
759 struct sock_filter
*code
;
760 err
= get_filter(argp
, &code
);
763 kfree(ppp
->active_filter
);
764 ppp
->active_filter
= code
;
765 ppp
->active_len
= err
;
771 #endif /* CONFIG_PPP_FILTER */
773 #ifdef CONFIG_PPP_MULTILINK
775 if (get_user(val
, p
))
779 ppp_recv_unlock(ppp
);
782 #endif /* CONFIG_PPP_MULTILINK */
791 static int ppp_unattached_ioctl(struct net
*net
, struct ppp_file
*pf
,
792 struct file
*file
, unsigned int cmd
, unsigned long arg
)
794 int unit
, err
= -EFAULT
;
796 struct channel
*chan
;
798 int __user
*p
= (int __user
*)arg
;
803 /* Create a new ppp unit */
804 if (get_user(unit
, p
))
806 ppp
= ppp_create_interface(net
, unit
, &err
);
809 file
->private_data
= &ppp
->file
;
812 if (put_user(ppp
->file
.index
, p
))
818 /* Attach to an existing ppp unit */
819 if (get_user(unit
, p
))
822 pn
= ppp_pernet(net
);
823 mutex_lock(&pn
->all_ppp_mutex
);
824 ppp
= ppp_find_unit(pn
, unit
);
826 atomic_inc(&ppp
->file
.refcnt
);
827 file
->private_data
= &ppp
->file
;
830 mutex_unlock(&pn
->all_ppp_mutex
);
834 if (get_user(unit
, p
))
837 pn
= ppp_pernet(net
);
838 spin_lock_bh(&pn
->all_channels_lock
);
839 chan
= ppp_find_channel(pn
, unit
);
841 atomic_inc(&chan
->file
.refcnt
);
842 file
->private_data
= &chan
->file
;
845 spin_unlock_bh(&pn
->all_channels_lock
);
855 static const struct file_operations ppp_device_fops
= {
856 .owner
= THIS_MODULE
,
860 .unlocked_ioctl
= ppp_ioctl
,
862 .release
= ppp_release
865 static __net_init
int ppp_init_net(struct net
*net
)
870 pn
= kzalloc(sizeof(*pn
), GFP_KERNEL
);
874 idr_init(&pn
->units_idr
);
875 mutex_init(&pn
->all_ppp_mutex
);
877 INIT_LIST_HEAD(&pn
->all_channels
);
878 INIT_LIST_HEAD(&pn
->new_channels
);
880 spin_lock_init(&pn
->all_channels_lock
);
882 err
= net_assign_generic(net
, ppp_net_id
, pn
);
891 static __net_exit
void ppp_exit_net(struct net
*net
)
895 pn
= net_generic(net
, ppp_net_id
);
896 idr_destroy(&pn
->units_idr
);
898 * if someone has cached our net then
899 * further net_generic call will return NULL
901 net_assign_generic(net
, ppp_net_id
, NULL
);
905 static struct pernet_operations ppp_net_ops
= {
906 .init
= ppp_init_net
,
907 .exit
= ppp_exit_net
,
910 #define PPP_MAJOR 108
912 /* Called at boot time if ppp is compiled into the kernel,
913 or at module load time (from init_module) if compiled as a module. */
914 static int __init
ppp_init(void)
918 printk(KERN_INFO
"PPP generic driver version " PPP_VERSION
"\n");
920 err
= register_pernet_gen_device(&ppp_net_id
, &ppp_net_ops
);
922 printk(KERN_ERR
"failed to register PPP pernet device (%d)\n", err
);
926 err
= register_chrdev(PPP_MAJOR
, "ppp", &ppp_device_fops
);
928 printk(KERN_ERR
"failed to register PPP device (%d)\n", err
);
932 ppp_class
= class_create(THIS_MODULE
, "ppp");
933 if (IS_ERR(ppp_class
)) {
934 err
= PTR_ERR(ppp_class
);
938 /* not a big deal if we fail here :-) */
939 device_create(ppp_class
, NULL
, MKDEV(PPP_MAJOR
, 0), NULL
, "ppp");
944 unregister_chrdev(PPP_MAJOR
, "ppp");
946 unregister_pernet_gen_device(ppp_net_id
, &ppp_net_ops
);
952 * Network interface unit routines.
955 ppp_start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
957 struct ppp
*ppp
= netdev_priv(dev
);
961 npi
= ethertype_to_npindex(ntohs(skb
->protocol
));
965 /* Drop, accept or reject the packet */
966 switch (ppp
->npmode
[npi
]) {
970 /* it would be nice to have a way to tell the network
971 system to queue this one up for later. */
978 /* Put the 2-byte PPP protocol number on the front,
979 making sure there is room for the address and control fields. */
980 if (skb_cow_head(skb
, PPP_HDRLEN
))
983 pp
= skb_push(skb
, 2);
984 proto
= npindex_to_proto
[npi
];
988 netif_stop_queue(dev
);
989 skb_queue_tail(&ppp
->file
.xq
, skb
);
990 ppp_xmit_process(ppp
);
995 ++dev
->stats
.tx_dropped
;
1000 ppp_net_ioctl(struct net_device
*dev
, struct ifreq
*ifr
, int cmd
)
1002 struct ppp
*ppp
= netdev_priv(dev
);
1004 void __user
*addr
= (void __user
*) ifr
->ifr_ifru
.ifru_data
;
1005 struct ppp_stats stats
;
1006 struct ppp_comp_stats cstats
;
1011 ppp_get_stats(ppp
, &stats
);
1012 if (copy_to_user(addr
, &stats
, sizeof(stats
)))
1017 case SIOCGPPPCSTATS
:
1018 memset(&cstats
, 0, sizeof(cstats
));
1020 ppp
->xcomp
->comp_stat(ppp
->xc_state
, &cstats
.c
);
1022 ppp
->rcomp
->decomp_stat(ppp
->rc_state
, &cstats
.d
);
1023 if (copy_to_user(addr
, &cstats
, sizeof(cstats
)))
1030 if (copy_to_user(addr
, vers
, strlen(vers
) + 1))
1042 static const struct net_device_ops ppp_netdev_ops
= {
1043 .ndo_start_xmit
= ppp_start_xmit
,
1044 .ndo_do_ioctl
= ppp_net_ioctl
,
1047 static void ppp_setup(struct net_device
*dev
)
1049 dev
->netdev_ops
= &ppp_netdev_ops
;
1050 dev
->hard_header_len
= PPP_HDRLEN
;
1053 dev
->tx_queue_len
= 3;
1054 dev
->type
= ARPHRD_PPP
;
1055 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
1056 dev
->features
|= NETIF_F_NETNS_LOCAL
;
1060 * Transmit-side routines.
1064 * Called to do any work queued up on the transmit side
1065 * that can now be done.
1068 ppp_xmit_process(struct ppp
*ppp
)
1070 struct sk_buff
*skb
;
1073 if (!ppp
->closing
) {
1075 while (!ppp
->xmit_pending
1076 && (skb
= skb_dequeue(&ppp
->file
.xq
)))
1077 ppp_send_frame(ppp
, skb
);
1078 /* If there's no work left to do, tell the core net
1079 code that we can accept some more. */
1080 if (!ppp
->xmit_pending
&& !skb_peek(&ppp
->file
.xq
))
1081 netif_wake_queue(ppp
->dev
);
1083 ppp_xmit_unlock(ppp
);
1086 static inline struct sk_buff
*
1087 pad_compress_skb(struct ppp
*ppp
, struct sk_buff
*skb
)
1089 struct sk_buff
*new_skb
;
1091 int new_skb_size
= ppp
->dev
->mtu
+
1092 ppp
->xcomp
->comp_extra
+ ppp
->dev
->hard_header_len
;
1093 int compressor_skb_size
= ppp
->dev
->mtu
+
1094 ppp
->xcomp
->comp_extra
+ PPP_HDRLEN
;
1095 new_skb
= alloc_skb(new_skb_size
, GFP_ATOMIC
);
1097 if (net_ratelimit())
1098 printk(KERN_ERR
"PPP: no memory (comp pkt)\n");
1101 if (ppp
->dev
->hard_header_len
> PPP_HDRLEN
)
1102 skb_reserve(new_skb
,
1103 ppp
->dev
->hard_header_len
- PPP_HDRLEN
);
1105 /* compressor still expects A/C bytes in hdr */
1106 len
= ppp
->xcomp
->compress(ppp
->xc_state
, skb
->data
- 2,
1107 new_skb
->data
, skb
->len
+ 2,
1108 compressor_skb_size
);
1109 if (len
> 0 && (ppp
->flags
& SC_CCP_UP
)) {
1113 skb_pull(skb
, 2); /* pull off A/C bytes */
1114 } else if (len
== 0) {
1115 /* didn't compress, or CCP not up yet */
1121 * MPPE requires that we do not send unencrypted
1122 * frames. The compressor will return -1 if we
1123 * should drop the frame. We cannot simply test
1124 * the compress_proto because MPPE and MPPC share
1127 if (net_ratelimit())
1128 printk(KERN_ERR
"ppp: compressor dropped pkt\n");
1137 * Compress and send a frame.
1138 * The caller should have locked the xmit path,
1139 * and xmit_pending should be 0.
1142 ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1144 int proto
= PPP_PROTO(skb
);
1145 struct sk_buff
*new_skb
;
1149 if (proto
< 0x8000) {
1150 #ifdef CONFIG_PPP_FILTER
1151 /* check if we should pass this packet */
1152 /* the filter instructions are constructed assuming
1153 a four-byte PPP header on each packet */
1154 *skb_push(skb
, 2) = 1;
1155 if (ppp
->pass_filter
1156 && sk_run_filter(skb
, ppp
->pass_filter
,
1157 ppp
->pass_len
) == 0) {
1159 printk(KERN_DEBUG
"PPP: outbound frame not passed\n");
1163 /* if this packet passes the active filter, record the time */
1164 if (!(ppp
->active_filter
1165 && sk_run_filter(skb
, ppp
->active_filter
,
1166 ppp
->active_len
) == 0))
1167 ppp
->last_xmit
= jiffies
;
1170 /* for data packets, record the time */
1171 ppp
->last_xmit
= jiffies
;
1172 #endif /* CONFIG_PPP_FILTER */
1175 ++ppp
->dev
->stats
.tx_packets
;
1176 ppp
->dev
->stats
.tx_bytes
+= skb
->len
- 2;
1180 if (!ppp
->vj
|| (ppp
->flags
& SC_COMP_TCP
) == 0)
1182 /* try to do VJ TCP header compression */
1183 new_skb
= alloc_skb(skb
->len
+ ppp
->dev
->hard_header_len
- 2,
1186 printk(KERN_ERR
"PPP: no memory (VJ comp pkt)\n");
1189 skb_reserve(new_skb
, ppp
->dev
->hard_header_len
- 2);
1191 len
= slhc_compress(ppp
->vj
, cp
, skb
->len
- 2,
1192 new_skb
->data
+ 2, &cp
,
1193 !(ppp
->flags
& SC_NO_TCP_CCID
));
1194 if (cp
== skb
->data
+ 2) {
1195 /* didn't compress */
1198 if (cp
[0] & SL_TYPE_COMPRESSED_TCP
) {
1199 proto
= PPP_VJC_COMP
;
1200 cp
[0] &= ~SL_TYPE_COMPRESSED_TCP
;
1202 proto
= PPP_VJC_UNCOMP
;
1203 cp
[0] = skb
->data
[2];
1207 cp
= skb_put(skb
, len
+ 2);
1214 /* peek at outbound CCP frames */
1215 ppp_ccp_peek(ppp
, skb
, 0);
1219 /* try to do packet compression */
1220 if ((ppp
->xstate
& SC_COMP_RUN
) && ppp
->xc_state
1221 && proto
!= PPP_LCP
&& proto
!= PPP_CCP
) {
1222 if (!(ppp
->flags
& SC_CCP_UP
) && (ppp
->flags
& SC_MUST_COMP
)) {
1223 if (net_ratelimit())
1224 printk(KERN_ERR
"ppp: compression required but down - pkt dropped.\n");
1227 skb
= pad_compress_skb(ppp
, skb
);
1233 * If we are waiting for traffic (demand dialling),
1234 * queue it up for pppd to receive.
1236 if (ppp
->flags
& SC_LOOP_TRAFFIC
) {
1237 if (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
)
1239 skb_queue_tail(&ppp
->file
.rq
, skb
);
1240 wake_up_interruptible(&ppp
->file
.rwait
);
1244 ppp
->xmit_pending
= skb
;
1250 ++ppp
->dev
->stats
.tx_errors
;
1254 * Try to send the frame in xmit_pending.
1255 * The caller should have the xmit path locked.
1258 ppp_push(struct ppp
*ppp
)
1260 struct list_head
*list
;
1261 struct channel
*pch
;
1262 struct sk_buff
*skb
= ppp
->xmit_pending
;
1267 list
= &ppp
->channels
;
1268 if (list_empty(list
)) {
1269 /* nowhere to send the packet, just drop it */
1270 ppp
->xmit_pending
= NULL
;
1275 if ((ppp
->flags
& SC_MULTILINK
) == 0) {
1276 /* not doing multilink: send it down the first channel */
1278 pch
= list_entry(list
, struct channel
, clist
);
1280 spin_lock_bh(&pch
->downl
);
1282 if (pch
->chan
->ops
->start_xmit(pch
->chan
, skb
))
1283 ppp
->xmit_pending
= NULL
;
1285 /* channel got unregistered */
1287 ppp
->xmit_pending
= NULL
;
1289 spin_unlock_bh(&pch
->downl
);
1293 #ifdef CONFIG_PPP_MULTILINK
1294 /* Multilink: fragment the packet over as many links
1295 as can take the packet at the moment. */
1296 if (!ppp_mp_explode(ppp
, skb
))
1298 #endif /* CONFIG_PPP_MULTILINK */
1300 ppp
->xmit_pending
= NULL
;
1304 #ifdef CONFIG_PPP_MULTILINK
1306 * Divide a packet to be transmitted into fragments and
1307 * send them out the individual links.
1309 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
)
1312 int i
, bits
, hdrlen
, mtu
;
1314 int navail
, nfree
, nzero
;
1318 unsigned char *p
, *q
;
1319 struct list_head
*list
;
1320 struct channel
*pch
;
1321 struct sk_buff
*frag
;
1322 struct ppp_channel
*chan
;
1324 totspeed
= 0; /*total bitrate of the bundle*/
1325 nfree
= 0; /* # channels which have no packet already queued */
1326 navail
= 0; /* total # of usable channels (not deregistered) */
1327 nzero
= 0; /* number of channels with zero speed associated*/
1328 totfree
= 0; /*total # of channels available and
1329 *having no queued packets before
1330 *starting the fragmentation*/
1332 hdrlen
= (ppp
->flags
& SC_MP_XSHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1334 list_for_each_entry(pch
, &ppp
->channels
, clist
) {
1335 navail
+= pch
->avail
= (pch
->chan
!= NULL
);
1336 pch
->speed
= pch
->chan
->speed
;
1338 if (skb_queue_empty(&pch
->file
.xq
) ||
1340 if (pch
->speed
== 0)
1343 totspeed
+= pch
->speed
;
1349 if (!pch
->had_frag
&& i
< ppp
->nxchan
)
1355 * Don't start sending this packet unless at least half of
1356 * the channels are free. This gives much better TCP
1357 * performance if we have a lot of channels.
1359 if (nfree
== 0 || nfree
< navail
/ 2)
1360 return 0; /* can't take now, leave it in xmit_pending */
1362 /* Do protocol field compression (XXX this should be optional) */
1371 nbigger
= len
% nfree
;
1373 /* skip to the channel after the one we last used
1374 and start at that one */
1375 list
= &ppp
->channels
;
1376 for (i
= 0; i
< ppp
->nxchan
; ++i
) {
1378 if (list
== &ppp
->channels
) {
1384 /* create a fragment for each channel */
1388 if (list
== &ppp
->channels
) {
1392 pch
= list_entry(list
, struct channel
, clist
);
1398 * Skip this channel if it has a fragment pending already and
1399 * we haven't given a fragment to all of the free channels.
1401 if (pch
->avail
== 1) {
1408 /* check the channel's mtu and whether it is still attached. */
1409 spin_lock_bh(&pch
->downl
);
1410 if (pch
->chan
== NULL
) {
1411 /* can't use this channel, it's being deregistered */
1412 if (pch
->speed
== 0)
1415 totspeed
-= pch
->speed
;
1417 spin_unlock_bh(&pch
->downl
);
1428 *if the channel speed is not set divide
1429 *the packet evenly among the free channels;
1430 *otherwise divide it according to the speed
1431 *of the channel we are going to transmit on
1434 if (pch
->speed
== 0) {
1435 flen
= totlen
/nfree
;
1441 flen
= (((totfree
- nzero
)*(totlen
+ hdrlen
*totfree
)) /
1442 ((totspeed
*totfree
)/pch
->speed
)) - hdrlen
;
1444 flen
+= ((totfree
- nzero
)*pch
->speed
)/totspeed
;
1445 nbigger
-= ((totfree
- nzero
)*pch
->speed
)/
1453 *check if we are on the last channel or
1454 *we exceded the lenght of the data to
1457 if ((nfree
<= 0) || (flen
> len
))
1460 *it is not worth to tx on slow channels:
1461 *in that case from the resulting flen according to the
1462 *above formula will be equal or less than zero.
1463 *Skip the channel in this case
1467 spin_unlock_bh(&pch
->downl
);
1471 mtu
= pch
->chan
->mtu
- hdrlen
;
1478 frag
= alloc_skb(flen
+ hdrlen
+ (flen
== 0), GFP_ATOMIC
);
1481 q
= skb_put(frag
, flen
+ hdrlen
);
1483 /* make the MP header */
1486 if (ppp
->flags
& SC_MP_XSHORTSEQ
) {
1487 q
[2] = bits
+ ((ppp
->nxseq
>> 8) & 0xf);
1491 q
[3] = ppp
->nxseq
>> 16;
1492 q
[4] = ppp
->nxseq
>> 8;
1496 memcpy(q
+ hdrlen
, p
, flen
);
1498 /* try to send it down the channel */
1500 if (!skb_queue_empty(&pch
->file
.xq
) ||
1501 !chan
->ops
->start_xmit(chan
, frag
))
1502 skb_queue_tail(&pch
->file
.xq
, frag
);
1508 spin_unlock_bh(&pch
->downl
);
1515 spin_unlock_bh(&pch
->downl
);
1517 printk(KERN_ERR
"PPP: no memory (fragment)\n");
1518 ++ppp
->dev
->stats
.tx_errors
;
1520 return 1; /* abandon the frame */
1522 #endif /* CONFIG_PPP_MULTILINK */
1525 * Try to send data out on a channel.
1528 ppp_channel_push(struct channel
*pch
)
1530 struct sk_buff
*skb
;
1533 spin_lock_bh(&pch
->downl
);
1535 while (!skb_queue_empty(&pch
->file
.xq
)) {
1536 skb
= skb_dequeue(&pch
->file
.xq
);
1537 if (!pch
->chan
->ops
->start_xmit(pch
->chan
, skb
)) {
1538 /* put the packet back and try again later */
1539 skb_queue_head(&pch
->file
.xq
, skb
);
1544 /* channel got deregistered */
1545 skb_queue_purge(&pch
->file
.xq
);
1547 spin_unlock_bh(&pch
->downl
);
1548 /* see if there is anything from the attached unit to be sent */
1549 if (skb_queue_empty(&pch
->file
.xq
)) {
1550 read_lock_bh(&pch
->upl
);
1553 ppp_xmit_process(ppp
);
1554 read_unlock_bh(&pch
->upl
);
1559 * Receive-side routines.
1562 /* misuse a few fields of the skb for MP reconstruction */
1563 #define sequence priority
1564 #define BEbits cb[0]
1567 ppp_do_recv(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1571 ppp_receive_frame(ppp
, skb
, pch
);
1574 ppp_recv_unlock(ppp
);
1578 ppp_input(struct ppp_channel
*chan
, struct sk_buff
*skb
)
1580 struct channel
*pch
= chan
->ppp
;
1583 if (!pch
|| skb
->len
== 0) {
1588 proto
= PPP_PROTO(skb
);
1589 read_lock_bh(&pch
->upl
);
1590 if (!pch
->ppp
|| proto
>= 0xc000 || proto
== PPP_CCPFRAG
) {
1591 /* put it on the channel queue */
1592 skb_queue_tail(&pch
->file
.rq
, skb
);
1593 /* drop old frames if queue too long */
1594 while (pch
->file
.rq
.qlen
> PPP_MAX_RQLEN
1595 && (skb
= skb_dequeue(&pch
->file
.rq
)))
1597 wake_up_interruptible(&pch
->file
.rwait
);
1599 ppp_do_recv(pch
->ppp
, skb
, pch
);
1601 read_unlock_bh(&pch
->upl
);
1604 /* Put a 0-length skb in the receive queue as an error indication */
1606 ppp_input_error(struct ppp_channel
*chan
, int code
)
1608 struct channel
*pch
= chan
->ppp
;
1609 struct sk_buff
*skb
;
1614 read_lock_bh(&pch
->upl
);
1616 skb
= alloc_skb(0, GFP_ATOMIC
);
1618 skb
->len
= 0; /* probably unnecessary */
1620 ppp_do_recv(pch
->ppp
, skb
, pch
);
1623 read_unlock_bh(&pch
->upl
);
1627 * We come in here to process a received frame.
1628 * The receive side of the ppp unit is locked.
1631 ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1633 if (pskb_may_pull(skb
, 2)) {
1634 #ifdef CONFIG_PPP_MULTILINK
1635 /* XXX do channel-level decompression here */
1636 if (PPP_PROTO(skb
) == PPP_MP
)
1637 ppp_receive_mp_frame(ppp
, skb
, pch
);
1639 #endif /* CONFIG_PPP_MULTILINK */
1640 ppp_receive_nonmp_frame(ppp
, skb
);
1645 /* note: a 0-length skb is used as an error indication */
1646 ++ppp
->dev
->stats
.rx_length_errors
;
1649 ppp_receive_error(ppp
);
1653 ppp_receive_error(struct ppp
*ppp
)
1655 ++ppp
->dev
->stats
.rx_errors
;
1661 ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1664 int proto
, len
, npi
;
1667 * Decompress the frame, if compressed.
1668 * Note that some decompressors need to see uncompressed frames
1669 * that come in as well as compressed frames.
1671 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
)
1672 && (ppp
->rstate
& (SC_DC_FERROR
| SC_DC_ERROR
)) == 0)
1673 skb
= ppp_decompress_frame(ppp
, skb
);
1675 if (ppp
->flags
& SC_MUST_COMP
&& ppp
->rstate
& SC_DC_FERROR
)
1678 proto
= PPP_PROTO(skb
);
1681 /* decompress VJ compressed packets */
1682 if (!ppp
->vj
|| (ppp
->flags
& SC_REJ_COMP_TCP
))
1685 if (skb_tailroom(skb
) < 124 || skb_cloned(skb
)) {
1686 /* copy to a new sk_buff with more tailroom */
1687 ns
= dev_alloc_skb(skb
->len
+ 128);
1689 printk(KERN_ERR
"PPP: no memory (VJ decomp)\n");
1693 skb_copy_bits(skb
, 0, skb_put(ns
, skb
->len
), skb
->len
);
1698 skb
->ip_summed
= CHECKSUM_NONE
;
1700 len
= slhc_uncompress(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2);
1702 printk(KERN_DEBUG
"PPP: VJ decompression error\n");
1707 skb_put(skb
, len
- skb
->len
);
1708 else if (len
< skb
->len
)
1713 case PPP_VJC_UNCOMP
:
1714 if (!ppp
->vj
|| (ppp
->flags
& SC_REJ_COMP_TCP
))
1717 /* Until we fix the decompressor need to make sure
1718 * data portion is linear.
1720 if (!pskb_may_pull(skb
, skb
->len
))
1723 if (slhc_remember(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2) <= 0) {
1724 printk(KERN_ERR
"PPP: VJ uncompressed error\n");
1731 ppp_ccp_peek(ppp
, skb
, 1);
1735 ++ppp
->dev
->stats
.rx_packets
;
1736 ppp
->dev
->stats
.rx_bytes
+= skb
->len
- 2;
1738 npi
= proto_to_npindex(proto
);
1740 /* control or unknown frame - pass it to pppd */
1741 skb_queue_tail(&ppp
->file
.rq
, skb
);
1742 /* limit queue length by dropping old frames */
1743 while (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
1744 && (skb
= skb_dequeue(&ppp
->file
.rq
)))
1746 /* wake up any process polling or blocking on read */
1747 wake_up_interruptible(&ppp
->file
.rwait
);
1750 /* network protocol frame - give it to the kernel */
1752 #ifdef CONFIG_PPP_FILTER
1753 /* check if the packet passes the pass and active filters */
1754 /* the filter instructions are constructed assuming
1755 a four-byte PPP header on each packet */
1756 if (ppp
->pass_filter
|| ppp
->active_filter
) {
1757 if (skb_cloned(skb
) &&
1758 pskb_expand_head(skb
, 0, 0, GFP_ATOMIC
))
1761 *skb_push(skb
, 2) = 0;
1762 if (ppp
->pass_filter
1763 && sk_run_filter(skb
, ppp
->pass_filter
,
1764 ppp
->pass_len
) == 0) {
1766 printk(KERN_DEBUG
"PPP: inbound frame "
1771 if (!(ppp
->active_filter
1772 && sk_run_filter(skb
, ppp
->active_filter
,
1773 ppp
->active_len
) == 0))
1774 ppp
->last_recv
= jiffies
;
1777 #endif /* CONFIG_PPP_FILTER */
1778 ppp
->last_recv
= jiffies
;
1780 if ((ppp
->dev
->flags
& IFF_UP
) == 0
1781 || ppp
->npmode
[npi
] != NPMODE_PASS
) {
1784 /* chop off protocol */
1785 skb_pull_rcsum(skb
, 2);
1786 skb
->dev
= ppp
->dev
;
1787 skb
->protocol
= htons(npindex_to_ethertype
[npi
]);
1788 skb_reset_mac_header(skb
);
1796 ppp_receive_error(ppp
);
1799 static struct sk_buff
*
1800 ppp_decompress_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1802 int proto
= PPP_PROTO(skb
);
1806 /* Until we fix all the decompressor's need to make sure
1807 * data portion is linear.
1809 if (!pskb_may_pull(skb
, skb
->len
))
1812 if (proto
== PPP_COMP
) {
1815 switch(ppp
->rcomp
->compress_proto
) {
1817 obuff_size
= ppp
->mru
+ PPP_HDRLEN
+ 1;
1820 obuff_size
= ppp
->mru
+ PPP_HDRLEN
;
1824 ns
= dev_alloc_skb(obuff_size
);
1826 printk(KERN_ERR
"ppp_decompress_frame: no memory\n");
1829 /* the decompressor still expects the A/C bytes in the hdr */
1830 len
= ppp
->rcomp
->decompress(ppp
->rc_state
, skb
->data
- 2,
1831 skb
->len
+ 2, ns
->data
, obuff_size
);
1833 /* Pass the compressed frame to pppd as an
1834 error indication. */
1835 if (len
== DECOMP_FATALERROR
)
1836 ppp
->rstate
|= SC_DC_FERROR
;
1844 skb_pull(skb
, 2); /* pull off the A/C bytes */
1847 /* Uncompressed frame - pass to decompressor so it
1848 can update its dictionary if necessary. */
1849 if (ppp
->rcomp
->incomp
)
1850 ppp
->rcomp
->incomp(ppp
->rc_state
, skb
->data
- 2,
1857 ppp
->rstate
|= SC_DC_ERROR
;
1858 ppp_receive_error(ppp
);
1862 #ifdef CONFIG_PPP_MULTILINK
1864 * Receive a multilink frame.
1865 * We put it on the reconstruction queue and then pull off
1866 * as many completed frames as we can.
1869 ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1873 int mphdrlen
= (ppp
->flags
& SC_MP_SHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1875 if (!pskb_may_pull(skb
, mphdrlen
+ 1) || ppp
->mrru
== 0)
1876 goto err
; /* no good, throw it away */
1878 /* Decode sequence number and begin/end bits */
1879 if (ppp
->flags
& SC_MP_SHORTSEQ
) {
1880 seq
= ((skb
->data
[2] & 0x0f) << 8) | skb
->data
[3];
1883 seq
= (skb
->data
[3] << 16) | (skb
->data
[4] << 8)| skb
->data
[5];
1886 skb
->BEbits
= skb
->data
[2];
1887 skb_pull(skb
, mphdrlen
); /* pull off PPP and MP headers */
1890 * Do protocol ID decompression on the first fragment of each packet.
1892 if ((skb
->BEbits
& B
) && (skb
->data
[0] & 1))
1893 *skb_push(skb
, 1) = 0;
1896 * Expand sequence number to 32 bits, making it as close
1897 * as possible to ppp->minseq.
1899 seq
|= ppp
->minseq
& ~mask
;
1900 if ((int)(ppp
->minseq
- seq
) > (int)(mask
>> 1))
1902 else if ((int)(seq
- ppp
->minseq
) > (int)(mask
>> 1))
1903 seq
-= mask
+ 1; /* should never happen */
1904 skb
->sequence
= seq
;
1908 * If this packet comes before the next one we were expecting,
1911 if (seq_before(seq
, ppp
->nextseq
)) {
1913 ++ppp
->dev
->stats
.rx_dropped
;
1914 ppp_receive_error(ppp
);
1919 * Reevaluate minseq, the minimum over all channels of the
1920 * last sequence number received on each channel. Because of
1921 * the increasing sequence number rule, we know that any fragment
1922 * before `minseq' which hasn't arrived is never going to arrive.
1923 * The list of channels can't change because we have the receive
1924 * side of the ppp unit locked.
1926 list_for_each_entry(ch
, &ppp
->channels
, clist
) {
1927 if (seq_before(ch
->lastseq
, seq
))
1930 if (seq_before(ppp
->minseq
, seq
))
1933 /* Put the fragment on the reconstruction queue */
1934 ppp_mp_insert(ppp
, skb
);
1936 /* If the queue is getting long, don't wait any longer for packets
1937 before the start of the queue. */
1938 if (skb_queue_len(&ppp
->mrq
) >= PPP_MP_MAX_QLEN
) {
1939 struct sk_buff
*skb
= skb_peek(&ppp
->mrq
);
1940 if (seq_before(ppp
->minseq
, skb
->sequence
))
1941 ppp
->minseq
= skb
->sequence
;
1944 /* Pull completed packets off the queue and receive them. */
1945 while ((skb
= ppp_mp_reconstruct(ppp
)))
1946 ppp_receive_nonmp_frame(ppp
, skb
);
1952 ppp_receive_error(ppp
);
1956 * Insert a fragment on the MP reconstruction queue.
1957 * The queue is ordered by increasing sequence number.
1960 ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
)
1963 struct sk_buff_head
*list
= &ppp
->mrq
;
1964 u32 seq
= skb
->sequence
;
1966 /* N.B. we don't need to lock the list lock because we have the
1967 ppp unit receive-side lock. */
1968 skb_queue_walk(list
, p
) {
1969 if (seq_before(seq
, p
->sequence
))
1972 __skb_queue_before(list
, p
, skb
);
1976 * Reconstruct a packet from the MP fragment queue.
1977 * We go through increasing sequence numbers until we find a
1978 * complete packet, or we get to the sequence number for a fragment
1979 * which hasn't arrived but might still do so.
1981 static struct sk_buff
*
1982 ppp_mp_reconstruct(struct ppp
*ppp
)
1984 u32 seq
= ppp
->nextseq
;
1985 u32 minseq
= ppp
->minseq
;
1986 struct sk_buff_head
*list
= &ppp
->mrq
;
1987 struct sk_buff
*p
, *next
;
1988 struct sk_buff
*head
, *tail
;
1989 struct sk_buff
*skb
= NULL
;
1990 int lost
= 0, len
= 0;
1992 if (ppp
->mrru
== 0) /* do nothing until mrru is set */
1996 for (p
= head
; p
!= (struct sk_buff
*) list
; p
= next
) {
1998 if (seq_before(p
->sequence
, seq
)) {
1999 /* this can't happen, anyway ignore the skb */
2000 printk(KERN_ERR
"ppp_mp_reconstruct bad seq %u < %u\n",
2005 if (p
->sequence
!= seq
) {
2006 /* Fragment `seq' is missing. If it is after
2007 minseq, it might arrive later, so stop here. */
2008 if (seq_after(seq
, minseq
))
2010 /* Fragment `seq' is lost, keep going. */
2012 seq
= seq_before(minseq
, p
->sequence
)?
2013 minseq
+ 1: p
->sequence
;
2019 * At this point we know that all the fragments from
2020 * ppp->nextseq to seq are either present or lost.
2021 * Also, there are no complete packets in the queue
2022 * that have no missing fragments and end before this
2026 /* B bit set indicates this fragment starts a packet */
2027 if (p
->BEbits
& B
) {
2035 /* Got a complete packet yet? */
2036 if (lost
== 0 && (p
->BEbits
& E
) && (head
->BEbits
& B
)) {
2037 if (len
> ppp
->mrru
+ 2) {
2038 ++ppp
->dev
->stats
.rx_length_errors
;
2039 printk(KERN_DEBUG
"PPP: reconstructed packet"
2040 " is too long (%d)\n", len
);
2041 } else if (p
== head
) {
2042 /* fragment is complete packet - reuse skb */
2046 } else if ((skb
= dev_alloc_skb(len
)) == NULL
) {
2047 ++ppp
->dev
->stats
.rx_missed_errors
;
2048 printk(KERN_DEBUG
"PPP: no memory for "
2049 "reconstructed packet");
2054 ppp
->nextseq
= seq
+ 1;
2058 * If this is the ending fragment of a packet,
2059 * and we haven't found a complete valid packet yet,
2060 * we can discard up to and including this fragment.
2068 /* If we have a complete packet, copy it all into one skb. */
2070 /* If we have discarded any fragments,
2071 signal a receive error. */
2072 if (head
->sequence
!= ppp
->nextseq
) {
2074 printk(KERN_DEBUG
" missed pkts %u..%u\n",
2075 ppp
->nextseq
, head
->sequence
-1);
2076 ++ppp
->dev
->stats
.rx_dropped
;
2077 ppp_receive_error(ppp
);
2081 /* copy to a single skb */
2082 for (p
= head
; p
!= tail
->next
; p
= p
->next
)
2083 skb_copy_bits(p
, 0, skb_put(skb
, p
->len
), p
->len
);
2084 ppp
->nextseq
= tail
->sequence
+ 1;
2088 /* Discard all the skbuffs that we have copied the data out of
2089 or that we can't use. */
2090 while ((p
= list
->next
) != head
) {
2091 __skb_unlink(p
, list
);
2097 #endif /* CONFIG_PPP_MULTILINK */
2100 * Channel interface.
2103 /* Create a new, unattached ppp channel. */
2104 int ppp_register_channel(struct ppp_channel
*chan
)
2106 return ppp_register_net_channel(current
->nsproxy
->net_ns
, chan
);
2109 /* Create a new, unattached ppp channel for specified net. */
2110 int ppp_register_net_channel(struct net
*net
, struct ppp_channel
*chan
)
2112 struct channel
*pch
;
2115 pch
= kzalloc(sizeof(struct channel
), GFP_KERNEL
);
2119 pn
= ppp_pernet(net
);
2123 pch
->chan_net
= net
;
2125 init_ppp_file(&pch
->file
, CHANNEL
);
2126 pch
->file
.hdrlen
= chan
->hdrlen
;
2127 #ifdef CONFIG_PPP_MULTILINK
2129 #endif /* CONFIG_PPP_MULTILINK */
2130 init_rwsem(&pch
->chan_sem
);
2131 spin_lock_init(&pch
->downl
);
2132 rwlock_init(&pch
->upl
);
2134 spin_lock_bh(&pn
->all_channels_lock
);
2135 pch
->file
.index
= ++pn
->last_channel_index
;
2136 list_add(&pch
->list
, &pn
->new_channels
);
2137 atomic_inc(&channel_count
);
2138 spin_unlock_bh(&pn
->all_channels_lock
);
2144 * Return the index of a channel.
2146 int ppp_channel_index(struct ppp_channel
*chan
)
2148 struct channel
*pch
= chan
->ppp
;
2151 return pch
->file
.index
;
2156 * Return the PPP unit number to which a channel is connected.
2158 int ppp_unit_number(struct ppp_channel
*chan
)
2160 struct channel
*pch
= chan
->ppp
;
2164 read_lock_bh(&pch
->upl
);
2166 unit
= pch
->ppp
->file
.index
;
2167 read_unlock_bh(&pch
->upl
);
2173 * Disconnect a channel from the generic layer.
2174 * This must be called in process context.
2177 ppp_unregister_channel(struct ppp_channel
*chan
)
2179 struct channel
*pch
= chan
->ppp
;
2183 return; /* should never happen */
2188 * This ensures that we have returned from any calls into the
2189 * the channel's start_xmit or ioctl routine before we proceed.
2191 down_write(&pch
->chan_sem
);
2192 spin_lock_bh(&pch
->downl
);
2194 spin_unlock_bh(&pch
->downl
);
2195 up_write(&pch
->chan_sem
);
2196 ppp_disconnect_channel(pch
);
2198 pn
= ppp_pernet(pch
->chan_net
);
2199 spin_lock_bh(&pn
->all_channels_lock
);
2200 list_del(&pch
->list
);
2201 spin_unlock_bh(&pn
->all_channels_lock
);
2204 wake_up_interruptible(&pch
->file
.rwait
);
2205 if (atomic_dec_and_test(&pch
->file
.refcnt
))
2206 ppp_destroy_channel(pch
);
2210 * Callback from a channel when it can accept more to transmit.
2211 * This should be called at BH/softirq level, not interrupt level.
2214 ppp_output_wakeup(struct ppp_channel
*chan
)
2216 struct channel
*pch
= chan
->ppp
;
2220 ppp_channel_push(pch
);
2224 * Compression control.
2227 /* Process the PPPIOCSCOMPRESS ioctl. */
2229 ppp_set_compress(struct ppp
*ppp
, unsigned long arg
)
2232 struct compressor
*cp
, *ocomp
;
2233 struct ppp_option_data data
;
2234 void *state
, *ostate
;
2235 unsigned char ccp_option
[CCP_MAX_OPTION_LENGTH
];
2238 if (copy_from_user(&data
, (void __user
*) arg
, sizeof(data
))
2239 || (data
.length
<= CCP_MAX_OPTION_LENGTH
2240 && copy_from_user(ccp_option
, (void __user
*) data
.ptr
, data
.length
)))
2243 if (data
.length
> CCP_MAX_OPTION_LENGTH
2244 || ccp_option
[1] < 2 || ccp_option
[1] > data
.length
)
2247 cp
= try_then_request_module(
2248 find_compressor(ccp_option
[0]),
2249 "ppp-compress-%d", ccp_option
[0]);
2254 if (data
.transmit
) {
2255 state
= cp
->comp_alloc(ccp_option
, data
.length
);
2258 ppp
->xstate
&= ~SC_COMP_RUN
;
2260 ostate
= ppp
->xc_state
;
2262 ppp
->xc_state
= state
;
2263 ppp_xmit_unlock(ppp
);
2265 ocomp
->comp_free(ostate
);
2266 module_put(ocomp
->owner
);
2270 module_put(cp
->owner
);
2273 state
= cp
->decomp_alloc(ccp_option
, data
.length
);
2276 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2278 ostate
= ppp
->rc_state
;
2280 ppp
->rc_state
= state
;
2281 ppp_recv_unlock(ppp
);
2283 ocomp
->decomp_free(ostate
);
2284 module_put(ocomp
->owner
);
2288 module_put(cp
->owner
);
2296 * Look at a CCP packet and update our state accordingly.
2297 * We assume the caller has the xmit or recv path locked.
2300 ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
)
2305 if (!pskb_may_pull(skb
, CCP_HDRLEN
+ 2))
2306 return; /* no header */
2309 switch (CCP_CODE(dp
)) {
2312 /* A ConfReq starts negotiation of compression
2313 * in one direction of transmission,
2314 * and hence brings it down...but which way?
2317 * A ConfReq indicates what the sender would like to receive
2320 /* He is proposing what I should send */
2321 ppp
->xstate
&= ~SC_COMP_RUN
;
2323 /* I am proposing to what he should send */
2324 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2331 * CCP is going down, both directions of transmission
2333 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2334 ppp
->xstate
&= ~SC_COMP_RUN
;
2338 if ((ppp
->flags
& (SC_CCP_OPEN
| SC_CCP_UP
)) != SC_CCP_OPEN
)
2340 len
= CCP_LENGTH(dp
);
2341 if (!pskb_may_pull(skb
, len
+ 2))
2342 return; /* too short */
2345 if (len
< CCP_OPT_MINLEN
|| len
< CCP_OPT_LENGTH(dp
))
2348 /* we will start receiving compressed packets */
2351 if (ppp
->rcomp
->decomp_init(ppp
->rc_state
, dp
, len
,
2352 ppp
->file
.index
, 0, ppp
->mru
, ppp
->debug
)) {
2353 ppp
->rstate
|= SC_DECOMP_RUN
;
2354 ppp
->rstate
&= ~(SC_DC_ERROR
| SC_DC_FERROR
);
2357 /* we will soon start sending compressed packets */
2360 if (ppp
->xcomp
->comp_init(ppp
->xc_state
, dp
, len
,
2361 ppp
->file
.index
, 0, ppp
->debug
))
2362 ppp
->xstate
|= SC_COMP_RUN
;
2367 /* reset the [de]compressor */
2368 if ((ppp
->flags
& SC_CCP_UP
) == 0)
2371 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
)) {
2372 ppp
->rcomp
->decomp_reset(ppp
->rc_state
);
2373 ppp
->rstate
&= ~SC_DC_ERROR
;
2376 if (ppp
->xc_state
&& (ppp
->xstate
& SC_COMP_RUN
))
2377 ppp
->xcomp
->comp_reset(ppp
->xc_state
);
2383 /* Free up compression resources. */
2385 ppp_ccp_closed(struct ppp
*ppp
)
2387 void *xstate
, *rstate
;
2388 struct compressor
*xcomp
, *rcomp
;
2391 ppp
->flags
&= ~(SC_CCP_OPEN
| SC_CCP_UP
);
2394 xstate
= ppp
->xc_state
;
2395 ppp
->xc_state
= NULL
;
2398 rstate
= ppp
->rc_state
;
2399 ppp
->rc_state
= NULL
;
2403 xcomp
->comp_free(xstate
);
2404 module_put(xcomp
->owner
);
2407 rcomp
->decomp_free(rstate
);
2408 module_put(rcomp
->owner
);
2412 /* List of compressors. */
2413 static LIST_HEAD(compressor_list
);
2414 static DEFINE_SPINLOCK(compressor_list_lock
);
2416 struct compressor_entry
{
2417 struct list_head list
;
2418 struct compressor
*comp
;
2421 static struct compressor_entry
*
2422 find_comp_entry(int proto
)
2424 struct compressor_entry
*ce
;
2426 list_for_each_entry(ce
, &compressor_list
, list
) {
2427 if (ce
->comp
->compress_proto
== proto
)
2433 /* Register a compressor */
2435 ppp_register_compressor(struct compressor
*cp
)
2437 struct compressor_entry
*ce
;
2439 spin_lock(&compressor_list_lock
);
2441 if (find_comp_entry(cp
->compress_proto
))
2444 ce
= kmalloc(sizeof(struct compressor_entry
), GFP_ATOMIC
);
2449 list_add(&ce
->list
, &compressor_list
);
2451 spin_unlock(&compressor_list_lock
);
2455 /* Unregister a compressor */
2457 ppp_unregister_compressor(struct compressor
*cp
)
2459 struct compressor_entry
*ce
;
2461 spin_lock(&compressor_list_lock
);
2462 ce
= find_comp_entry(cp
->compress_proto
);
2463 if (ce
&& ce
->comp
== cp
) {
2464 list_del(&ce
->list
);
2467 spin_unlock(&compressor_list_lock
);
2470 /* Find a compressor. */
2471 static struct compressor
*
2472 find_compressor(int type
)
2474 struct compressor_entry
*ce
;
2475 struct compressor
*cp
= NULL
;
2477 spin_lock(&compressor_list_lock
);
2478 ce
= find_comp_entry(type
);
2481 if (!try_module_get(cp
->owner
))
2484 spin_unlock(&compressor_list_lock
);
2489 * Miscelleneous stuff.
2493 ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
)
2495 struct slcompress
*vj
= ppp
->vj
;
2497 memset(st
, 0, sizeof(*st
));
2498 st
->p
.ppp_ipackets
= ppp
->dev
->stats
.rx_packets
;
2499 st
->p
.ppp_ierrors
= ppp
->dev
->stats
.rx_errors
;
2500 st
->p
.ppp_ibytes
= ppp
->dev
->stats
.rx_bytes
;
2501 st
->p
.ppp_opackets
= ppp
->dev
->stats
.tx_packets
;
2502 st
->p
.ppp_oerrors
= ppp
->dev
->stats
.tx_errors
;
2503 st
->p
.ppp_obytes
= ppp
->dev
->stats
.tx_bytes
;
2506 st
->vj
.vjs_packets
= vj
->sls_o_compressed
+ vj
->sls_o_uncompressed
;
2507 st
->vj
.vjs_compressed
= vj
->sls_o_compressed
;
2508 st
->vj
.vjs_searches
= vj
->sls_o_searches
;
2509 st
->vj
.vjs_misses
= vj
->sls_o_misses
;
2510 st
->vj
.vjs_errorin
= vj
->sls_i_error
;
2511 st
->vj
.vjs_tossed
= vj
->sls_i_tossed
;
2512 st
->vj
.vjs_uncompressedin
= vj
->sls_i_uncompressed
;
2513 st
->vj
.vjs_compressedin
= vj
->sls_i_compressed
;
2517 * Stuff for handling the lists of ppp units and channels
2518 * and for initialization.
2522 * Create a new ppp interface unit. Fails if it can't allocate memory
2523 * or if there is already a unit with the requested number.
2524 * unit == -1 means allocate a new number.
2527 ppp_create_interface(struct net
*net
, int unit
, int *retp
)
2531 struct net_device
*dev
= NULL
;
2535 dev
= alloc_netdev(sizeof(struct ppp
), "", ppp_setup
);
2539 pn
= ppp_pernet(net
);
2541 ppp
= netdev_priv(dev
);
2544 init_ppp_file(&ppp
->file
, INTERFACE
);
2545 ppp
->file
.hdrlen
= PPP_HDRLEN
- 2; /* don't count proto bytes */
2546 for (i
= 0; i
< NUM_NP
; ++i
)
2547 ppp
->npmode
[i
] = NPMODE_PASS
;
2548 INIT_LIST_HEAD(&ppp
->channels
);
2549 spin_lock_init(&ppp
->rlock
);
2550 spin_lock_init(&ppp
->wlock
);
2551 #ifdef CONFIG_PPP_MULTILINK
2553 skb_queue_head_init(&ppp
->mrq
);
2554 #endif /* CONFIG_PPP_MULTILINK */
2557 * drum roll: don't forget to set
2558 * the net device is belong to
2560 dev_net_set(dev
, net
);
2563 mutex_lock(&pn
->all_ppp_mutex
);
2566 unit
= unit_get(&pn
->units_idr
, ppp
);
2572 if (unit_find(&pn
->units_idr
, unit
))
2573 goto out2
; /* unit already exists */
2575 * if caller need a specified unit number
2576 * lets try to satisfy him, otherwise --
2577 * he should better ask us for new unit number
2579 * NOTE: yes I know that returning EEXIST it's not
2580 * fair but at least pppd will ask us to allocate
2581 * new unit in this case so user is happy :)
2583 unit
= unit_set(&pn
->units_idr
, ppp
, unit
);
2588 /* Initialize the new ppp unit */
2589 ppp
->file
.index
= unit
;
2590 sprintf(dev
->name
, "ppp%d", unit
);
2592 ret
= register_netdev(dev
);
2594 unit_put(&pn
->units_idr
, unit
);
2595 printk(KERN_ERR
"PPP: couldn't register device %s (%d)\n",
2602 atomic_inc(&ppp_unit_count
);
2603 mutex_unlock(&pn
->all_ppp_mutex
);
2609 mutex_unlock(&pn
->all_ppp_mutex
);
2617 * Initialize a ppp_file structure.
2620 init_ppp_file(struct ppp_file
*pf
, int kind
)
2623 skb_queue_head_init(&pf
->xq
);
2624 skb_queue_head_init(&pf
->rq
);
2625 atomic_set(&pf
->refcnt
, 1);
2626 init_waitqueue_head(&pf
->rwait
);
2630 * Take down a ppp interface unit - called when the owning file
2631 * (the one that created the unit) is closed or detached.
2633 static void ppp_shutdown_interface(struct ppp
*ppp
)
2637 pn
= ppp_pernet(ppp
->ppp_net
);
2638 mutex_lock(&pn
->all_ppp_mutex
);
2640 /* This will call dev_close() for us. */
2642 if (!ppp
->closing
) {
2645 unregister_netdev(ppp
->dev
);
2649 unit_put(&pn
->units_idr
, ppp
->file
.index
);
2652 wake_up_interruptible(&ppp
->file
.rwait
);
2654 mutex_unlock(&pn
->all_ppp_mutex
);
2658 * Free the memory used by a ppp unit. This is only called once
2659 * there are no channels connected to the unit and no file structs
2660 * that reference the unit.
2662 static void ppp_destroy_interface(struct ppp
*ppp
)
2664 atomic_dec(&ppp_unit_count
);
2666 if (!ppp
->file
.dead
|| ppp
->n_channels
) {
2667 /* "can't happen" */
2668 printk(KERN_ERR
"ppp: destroying ppp struct %p but dead=%d "
2669 "n_channels=%d !\n", ppp
, ppp
->file
.dead
,
2674 ppp_ccp_closed(ppp
);
2679 skb_queue_purge(&ppp
->file
.xq
);
2680 skb_queue_purge(&ppp
->file
.rq
);
2681 #ifdef CONFIG_PPP_MULTILINK
2682 skb_queue_purge(&ppp
->mrq
);
2683 #endif /* CONFIG_PPP_MULTILINK */
2684 #ifdef CONFIG_PPP_FILTER
2685 kfree(ppp
->pass_filter
);
2686 ppp
->pass_filter
= NULL
;
2687 kfree(ppp
->active_filter
);
2688 ppp
->active_filter
= NULL
;
2689 #endif /* CONFIG_PPP_FILTER */
2691 kfree_skb(ppp
->xmit_pending
);
2693 free_netdev(ppp
->dev
);
2697 * Locate an existing ppp unit.
2698 * The caller should have locked the all_ppp_mutex.
2701 ppp_find_unit(struct ppp_net
*pn
, int unit
)
2703 return unit_find(&pn
->units_idr
, unit
);
2707 * Locate an existing ppp channel.
2708 * The caller should have locked the all_channels_lock.
2709 * First we look in the new_channels list, then in the
2710 * all_channels list. If found in the new_channels list,
2711 * we move it to the all_channels list. This is for speed
2712 * when we have a lot of channels in use.
2714 static struct channel
*
2715 ppp_find_channel(struct ppp_net
*pn
, int unit
)
2717 struct channel
*pch
;
2719 list_for_each_entry(pch
, &pn
->new_channels
, list
) {
2720 if (pch
->file
.index
== unit
) {
2721 list_move(&pch
->list
, &pn
->all_channels
);
2726 list_for_each_entry(pch
, &pn
->all_channels
, list
) {
2727 if (pch
->file
.index
== unit
)
2735 * Connect a PPP channel to a PPP interface unit.
2738 ppp_connect_channel(struct channel
*pch
, int unit
)
2745 pn
= ppp_pernet(pch
->chan_net
);
2747 mutex_lock(&pn
->all_ppp_mutex
);
2748 ppp
= ppp_find_unit(pn
, unit
);
2751 write_lock_bh(&pch
->upl
);
2757 if (pch
->file
.hdrlen
> ppp
->file
.hdrlen
)
2758 ppp
->file
.hdrlen
= pch
->file
.hdrlen
;
2759 hdrlen
= pch
->file
.hdrlen
+ 2; /* for protocol bytes */
2760 if (hdrlen
> ppp
->dev
->hard_header_len
)
2761 ppp
->dev
->hard_header_len
= hdrlen
;
2762 list_add_tail(&pch
->clist
, &ppp
->channels
);
2765 atomic_inc(&ppp
->file
.refcnt
);
2770 write_unlock_bh(&pch
->upl
);
2772 mutex_unlock(&pn
->all_ppp_mutex
);
2777 * Disconnect a channel from its ppp unit.
2780 ppp_disconnect_channel(struct channel
*pch
)
2785 write_lock_bh(&pch
->upl
);
2788 write_unlock_bh(&pch
->upl
);
2790 /* remove it from the ppp unit's list */
2792 list_del(&pch
->clist
);
2793 if (--ppp
->n_channels
== 0)
2794 wake_up_interruptible(&ppp
->file
.rwait
);
2796 if (atomic_dec_and_test(&ppp
->file
.refcnt
))
2797 ppp_destroy_interface(ppp
);
2804 * Free up the resources used by a ppp channel.
2806 static void ppp_destroy_channel(struct channel
*pch
)
2808 atomic_dec(&channel_count
);
2810 if (!pch
->file
.dead
) {
2811 /* "can't happen" */
2812 printk(KERN_ERR
"ppp: destroying undead channel %p !\n",
2816 skb_queue_purge(&pch
->file
.xq
);
2817 skb_queue_purge(&pch
->file
.rq
);
2821 static void __exit
ppp_cleanup(void)
2823 /* should never happen */
2824 if (atomic_read(&ppp_unit_count
) || atomic_read(&channel_count
))
2825 printk(KERN_ERR
"PPP: removing module but units remain!\n");
2826 unregister_chrdev(PPP_MAJOR
, "ppp");
2827 device_destroy(ppp_class
, MKDEV(PPP_MAJOR
, 0));
2828 class_destroy(ppp_class
);
2829 unregister_pernet_gen_device(ppp_net_id
, &ppp_net_ops
);
2833 * Units handling. Caller must protect concurrent access
2834 * by holding all_ppp_mutex
2837 /* associate pointer with specified number */
2838 static int unit_set(struct idr
*p
, void *ptr
, int n
)
2843 if (!idr_pre_get(p
, GFP_KERNEL
)) {
2844 printk(KERN_ERR
"PPP: No free memory for idr\n");
2848 err
= idr_get_new_above(p
, ptr
, n
, &unit
);
2853 idr_remove(p
, unit
);
2860 /* get new free unit number and associate pointer with it */
2861 static int unit_get(struct idr
*p
, void *ptr
)
2866 if (!idr_pre_get(p
, GFP_KERNEL
)) {
2867 printk(KERN_ERR
"PPP: No free memory for idr\n");
2871 err
= idr_get_new_above(p
, ptr
, 0, &unit
);
2878 /* put unit number back to a pool */
2879 static void unit_put(struct idr
*p
, int n
)
2884 /* get pointer associated with the number */
2885 static void *unit_find(struct idr
*p
, int n
)
2887 return idr_find(p
, n
);
2890 /* Module/initialization stuff */
2892 module_init(ppp_init
);
2893 module_exit(ppp_cleanup
);
2895 EXPORT_SYMBOL(ppp_register_net_channel
);
2896 EXPORT_SYMBOL(ppp_register_channel
);
2897 EXPORT_SYMBOL(ppp_unregister_channel
);
2898 EXPORT_SYMBOL(ppp_channel_index
);
2899 EXPORT_SYMBOL(ppp_unit_number
);
2900 EXPORT_SYMBOL(ppp_input
);
2901 EXPORT_SYMBOL(ppp_input_error
);
2902 EXPORT_SYMBOL(ppp_output_wakeup
);
2903 EXPORT_SYMBOL(ppp_register_compressor
);
2904 EXPORT_SYMBOL(ppp_unregister_compressor
);
2905 MODULE_LICENSE("GPL");
2906 MODULE_ALIAS_CHARDEV_MAJOR(PPP_MAJOR
);
2907 MODULE_ALIAS("/dev/ppp");