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/ppp-ioctl.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/spinlock.h>
44 #include <linux/rwsem.h>
45 #include <linux/stddef.h>
46 #include <linux/device.h>
47 #include <linux/mutex.h>
48 #include <linux/slab.h>
49 #include <asm/unaligned.h>
50 #include <net/slhc_vj.h>
51 #include <linux/atomic.h>
53 #include <linux/nsproxy.h>
54 #include <net/net_namespace.h>
55 #include <net/netns/generic.h>
57 #define PPP_VERSION "2.4.2"
60 * Network protocols we support.
62 #define NP_IP 0 /* Internet Protocol V4 */
63 #define NP_IPV6 1 /* Internet Protocol V6 */
64 #define NP_IPX 2 /* IPX protocol */
65 #define NP_AT 3 /* Appletalk protocol */
66 #define NP_MPLS_UC 4 /* MPLS unicast */
67 #define NP_MPLS_MC 5 /* MPLS multicast */
68 #define NUM_NP 6 /* Number of NPs. */
70 #define MPHDRLEN 6 /* multilink protocol header length */
71 #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */
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 DEFINE_MUTEX(ppp_mutex
);
184 static atomic_t ppp_unit_count
= ATOMIC_INIT(0);
185 static atomic_t channel_count
= ATOMIC_INIT(0);
187 /* per-net private data for this module */
188 static int ppp_net_id __read_mostly
;
190 /* units to ppp mapping */
191 struct idr units_idr
;
194 * all_ppp_mutex protects the units_idr mapping.
195 * It also ensures that finding a ppp unit in the units_idr
196 * map and updating its file.refcnt field is atomic.
198 struct mutex all_ppp_mutex
;
201 struct list_head all_channels
;
202 struct list_head new_channels
;
203 int last_channel_index
;
206 * all_channels_lock protects all_channels and
207 * last_channel_index, and the atomicity of find
208 * a channel and updating its file.refcnt field.
210 spinlock_t all_channels_lock
;
213 /* Get the PPP protocol number from a skb */
214 #define PPP_PROTO(skb) get_unaligned_be16((skb)->data)
216 /* We limit the length of ppp->file.rq to this (arbitrary) value */
217 #define PPP_MAX_RQLEN 32
220 * Maximum number of multilink fragments queued up.
221 * This has to be large enough to cope with the maximum latency of
222 * the slowest channel relative to the others. Strictly it should
223 * depend on the number of channels and their characteristics.
225 #define PPP_MP_MAX_QLEN 128
227 /* Multilink header bits. */
228 #define B 0x80 /* this fragment begins a packet */
229 #define E 0x40 /* this fragment ends a packet */
231 /* Compare multilink sequence numbers (assumed to be 32 bits wide) */
232 #define seq_before(a, b) ((s32)((a) - (b)) < 0)
233 #define seq_after(a, b) ((s32)((a) - (b)) > 0)
236 static int ppp_unattached_ioctl(struct net
*net
, struct ppp_file
*pf
,
237 struct file
*file
, unsigned int cmd
, unsigned long arg
);
238 static int ppp_xmit_process(struct ppp
*ppp
);
239 static void ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
);
240 static void ppp_push(struct ppp
*ppp
);
241 static void ppp_channel_push(struct channel
*pch
);
242 static void ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
,
243 struct channel
*pch
);
244 static void ppp_receive_error(struct ppp
*ppp
);
245 static void ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
);
246 static struct sk_buff
*ppp_decompress_frame(struct ppp
*ppp
,
247 struct sk_buff
*skb
);
248 #ifdef CONFIG_PPP_MULTILINK
249 static void ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
,
250 struct channel
*pch
);
251 static void ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
);
252 static struct sk_buff
*ppp_mp_reconstruct(struct ppp
*ppp
);
253 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
);
254 #endif /* CONFIG_PPP_MULTILINK */
255 static int ppp_set_compress(struct ppp
*ppp
, unsigned long arg
);
256 static void ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
);
257 static void ppp_ccp_closed(struct ppp
*ppp
);
258 static struct compressor
*find_compressor(int type
);
259 static void ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
);
260 static struct ppp
*ppp_create_interface(struct net
*net
, int unit
, int *retp
);
261 static void init_ppp_file(struct ppp_file
*pf
, int kind
);
262 static void ppp_shutdown_interface(struct ppp
*ppp
);
263 static void ppp_destroy_interface(struct ppp
*ppp
);
264 static struct ppp
*ppp_find_unit(struct ppp_net
*pn
, int unit
);
265 static struct channel
*ppp_find_channel(struct ppp_net
*pn
, int unit
);
266 static int ppp_connect_channel(struct channel
*pch
, int unit
);
267 static int ppp_disconnect_channel(struct channel
*pch
);
268 static void ppp_destroy_channel(struct channel
*pch
);
269 static int unit_get(struct idr
*p
, void *ptr
);
270 static int unit_set(struct idr
*p
, void *ptr
, int n
);
271 static void unit_put(struct idr
*p
, int n
);
272 static void *unit_find(struct idr
*p
, int n
);
274 static struct class *ppp_class
;
276 /* per net-namespace data */
277 static inline struct ppp_net
*ppp_pernet(struct net
*net
)
281 return net_generic(net
, ppp_net_id
);
284 /* Translates a PPP protocol number to a NP index (NP == network protocol) */
285 static inline int proto_to_npindex(int proto
)
304 /* Translates an NP index into a PPP protocol number */
305 static const int npindex_to_proto
[NUM_NP
] = {
314 /* Translates an ethertype into an NP index */
315 static inline int ethertype_to_npindex(int ethertype
)
335 /* Translates an NP index into an ethertype */
336 static const int npindex_to_ethertype
[NUM_NP
] = {
348 #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock)
349 #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock)
350 #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock)
351 #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock)
352 #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \
353 ppp_recv_lock(ppp); } while (0)
354 #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \
355 ppp_xmit_unlock(ppp); } while (0)
358 * /dev/ppp device routines.
359 * The /dev/ppp device is used by pppd to control the ppp unit.
360 * It supports the read, write, ioctl and poll functions.
361 * Open instances of /dev/ppp can be in one of three states:
362 * unattached, attached to a ppp unit, or attached to a ppp channel.
364 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
;
413 add_wait_queue(&pf
->rwait
, &wait
);
415 set_current_state(TASK_INTERRUPTIBLE
);
416 skb
= skb_dequeue(&pf
->rq
);
422 if (pf
->kind
== INTERFACE
) {
424 * Return 0 (EOF) on an interface that has no
425 * channels connected, unless it is looping
426 * network traffic (demand mode).
428 struct ppp
*ppp
= PF_TO_PPP(pf
);
429 if (ppp
->n_channels
== 0 &&
430 (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0)
434 if (file
->f_flags
& O_NONBLOCK
)
437 if (signal_pending(current
))
441 set_current_state(TASK_RUNNING
);
442 remove_wait_queue(&pf
->rwait
, &wait
);
448 if (skb
->len
> count
)
453 if (skb_copy_datagram_iovec(skb
, 0, &iov
, skb
->len
))
463 static ssize_t
ppp_write(struct file
*file
, const char __user
*buf
,
464 size_t count
, loff_t
*ppos
)
466 struct ppp_file
*pf
= file
->private_data
;
473 skb
= alloc_skb(count
+ pf
->hdrlen
, GFP_KERNEL
);
476 skb_reserve(skb
, pf
->hdrlen
);
478 if (copy_from_user(skb_put(skb
, count
), buf
, count
)) {
483 skb_queue_tail(&pf
->xq
, skb
);
487 ppp_xmit_process(PF_TO_PPP(pf
));
490 ppp_channel_push(PF_TO_CHANNEL(pf
));
500 /* No kernel lock - fine */
501 static unsigned int ppp_poll(struct file
*file
, poll_table
*wait
)
503 struct ppp_file
*pf
= file
->private_data
;
508 poll_wait(file
, &pf
->rwait
, wait
);
509 mask
= POLLOUT
| POLLWRNORM
;
510 if (skb_peek(&pf
->rq
))
511 mask
|= POLLIN
| POLLRDNORM
;
514 else if (pf
->kind
== INTERFACE
) {
515 /* see comment in ppp_read */
516 struct ppp
*ppp
= PF_TO_PPP(pf
);
517 if (ppp
->n_channels
== 0 &&
518 (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0)
519 mask
|= POLLIN
| POLLRDNORM
;
525 #ifdef CONFIG_PPP_FILTER
526 static int get_filter(void __user
*arg
, struct sock_filter
**p
)
528 struct sock_fprog uprog
;
529 struct sock_filter
*code
= NULL
;
532 if (copy_from_user(&uprog
, arg
, sizeof(uprog
)))
540 len
= uprog
.len
* sizeof(struct sock_filter
);
541 code
= memdup_user(uprog
.filter
, len
);
543 return PTR_ERR(code
);
545 err
= sk_chk_filter(code
, uprog
.len
);
554 #endif /* CONFIG_PPP_FILTER */
556 static long ppp_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
558 struct ppp_file
*pf
= file
->private_data
;
560 int err
= -EFAULT
, val
, val2
, i
;
561 struct ppp_idle idle
;
564 struct slcompress
*vj
;
565 void __user
*argp
= (void __user
*)arg
;
566 int __user
*p
= argp
;
569 return ppp_unattached_ioctl(current
->nsproxy
->net_ns
,
572 if (cmd
== PPPIOCDETACH
) {
574 * We have to be careful here... if the file descriptor
575 * has been dup'd, we could have another process in the
576 * middle of a poll using the same file *, so we had
577 * better not free the interface data structures -
578 * instead we fail the ioctl. Even in this case, we
579 * shut down the interface if we are the owner of it.
580 * Actually, we should get rid of PPPIOCDETACH, userland
581 * (i.e. pppd) could achieve the same effect by closing
582 * this fd and reopening /dev/ppp.
585 mutex_lock(&ppp_mutex
);
586 if (pf
->kind
== INTERFACE
) {
588 if (file
== ppp
->owner
)
589 ppp_shutdown_interface(ppp
);
591 if (atomic_long_read(&file
->f_count
) <= 2) {
592 ppp_release(NULL
, file
);
595 pr_warn("PPPIOCDETACH file->f_count=%ld\n",
596 atomic_long_read(&file
->f_count
));
597 mutex_unlock(&ppp_mutex
);
601 if (pf
->kind
== CHANNEL
) {
603 struct ppp_channel
*chan
;
605 mutex_lock(&ppp_mutex
);
606 pch
= PF_TO_CHANNEL(pf
);
610 if (get_user(unit
, p
))
612 err
= ppp_connect_channel(pch
, unit
);
616 err
= ppp_disconnect_channel(pch
);
620 down_read(&pch
->chan_sem
);
623 if (chan
&& chan
->ops
->ioctl
)
624 err
= chan
->ops
->ioctl(chan
, cmd
, arg
);
625 up_read(&pch
->chan_sem
);
627 mutex_unlock(&ppp_mutex
);
631 if (pf
->kind
!= INTERFACE
) {
633 pr_err("PPP: not interface or channel??\n");
637 mutex_lock(&ppp_mutex
);
641 if (get_user(val
, p
))
648 if (get_user(val
, p
))
651 cflags
= ppp
->flags
& ~val
;
652 ppp
->flags
= val
& SC_FLAG_BITS
;
654 if (cflags
& SC_CCP_OPEN
)
660 val
= ppp
->flags
| ppp
->xstate
| ppp
->rstate
;
661 if (put_user(val
, p
))
666 case PPPIOCSCOMPRESS
:
667 err
= ppp_set_compress(ppp
, arg
);
671 if (put_user(ppp
->file
.index
, p
))
677 if (get_user(val
, p
))
684 if (put_user(ppp
->debug
, p
))
690 idle
.xmit_idle
= (jiffies
- ppp
->last_xmit
) / HZ
;
691 idle
.recv_idle
= (jiffies
- ppp
->last_recv
) / HZ
;
692 if (copy_to_user(argp
, &idle
, sizeof(idle
)))
698 if (get_user(val
, p
))
701 if ((val
>> 16) != 0) {
705 vj
= slhc_init(val2
+1, val
+1);
708 "PPP: no memory (VJ compressor)\n");
722 if (copy_from_user(&npi
, argp
, sizeof(npi
)))
724 err
= proto_to_npindex(npi
.protocol
);
728 if (cmd
== PPPIOCGNPMODE
) {
730 npi
.mode
= ppp
->npmode
[i
];
731 if (copy_to_user(argp
, &npi
, sizeof(npi
)))
734 ppp
->npmode
[i
] = npi
.mode
;
735 /* we may be able to transmit more packets now (??) */
736 netif_wake_queue(ppp
->dev
);
741 #ifdef CONFIG_PPP_FILTER
744 struct sock_filter
*code
;
745 err
= get_filter(argp
, &code
);
748 kfree(ppp
->pass_filter
);
749 ppp
->pass_filter
= code
;
758 struct sock_filter
*code
;
759 err
= get_filter(argp
, &code
);
762 kfree(ppp
->active_filter
);
763 ppp
->active_filter
= code
;
764 ppp
->active_len
= err
;
770 #endif /* CONFIG_PPP_FILTER */
772 #ifdef CONFIG_PPP_MULTILINK
774 if (get_user(val
, p
))
778 ppp_recv_unlock(ppp
);
781 #endif /* CONFIG_PPP_MULTILINK */
786 mutex_unlock(&ppp_mutex
);
790 static int ppp_unattached_ioctl(struct net
*net
, struct ppp_file
*pf
,
791 struct file
*file
, unsigned int cmd
, unsigned long arg
)
793 int unit
, err
= -EFAULT
;
795 struct channel
*chan
;
797 int __user
*p
= (int __user
*)arg
;
799 mutex_lock(&ppp_mutex
);
802 /* Create a new ppp unit */
803 if (get_user(unit
, p
))
805 ppp
= ppp_create_interface(net
, unit
, &err
);
808 file
->private_data
= &ppp
->file
;
811 if (put_user(ppp
->file
.index
, p
))
817 /* Attach to an existing ppp unit */
818 if (get_user(unit
, p
))
821 pn
= ppp_pernet(net
);
822 mutex_lock(&pn
->all_ppp_mutex
);
823 ppp
= ppp_find_unit(pn
, unit
);
825 atomic_inc(&ppp
->file
.refcnt
);
826 file
->private_data
= &ppp
->file
;
829 mutex_unlock(&pn
->all_ppp_mutex
);
833 if (get_user(unit
, p
))
836 pn
= ppp_pernet(net
);
837 spin_lock_bh(&pn
->all_channels_lock
);
838 chan
= ppp_find_channel(pn
, unit
);
840 atomic_inc(&chan
->file
.refcnt
);
841 file
->private_data
= &chan
->file
;
844 spin_unlock_bh(&pn
->all_channels_lock
);
850 mutex_unlock(&ppp_mutex
);
854 static const struct file_operations ppp_device_fops
= {
855 .owner
= THIS_MODULE
,
859 .unlocked_ioctl
= ppp_ioctl
,
861 .release
= ppp_release
,
862 .llseek
= noop_llseek
,
865 static __net_init
int ppp_init_net(struct net
*net
)
867 struct ppp_net
*pn
= net_generic(net
, ppp_net_id
);
869 idr_init(&pn
->units_idr
);
870 mutex_init(&pn
->all_ppp_mutex
);
872 INIT_LIST_HEAD(&pn
->all_channels
);
873 INIT_LIST_HEAD(&pn
->new_channels
);
875 spin_lock_init(&pn
->all_channels_lock
);
880 static __net_exit
void ppp_exit_net(struct net
*net
)
882 struct ppp_net
*pn
= net_generic(net
, ppp_net_id
);
884 idr_destroy(&pn
->units_idr
);
887 static struct pernet_operations ppp_net_ops
= {
888 .init
= ppp_init_net
,
889 .exit
= ppp_exit_net
,
891 .size
= sizeof(struct ppp_net
),
894 #define PPP_MAJOR 108
896 /* Called at boot time if ppp is compiled into the kernel,
897 or at module load time (from init_module) if compiled as a module. */
898 static int __init
ppp_init(void)
902 pr_info("PPP generic driver version " PPP_VERSION
"\n");
904 err
= register_pernet_device(&ppp_net_ops
);
906 pr_err("failed to register PPP pernet device (%d)\n", err
);
910 err
= register_chrdev(PPP_MAJOR
, "ppp", &ppp_device_fops
);
912 pr_err("failed to register PPP device (%d)\n", err
);
916 ppp_class
= class_create(THIS_MODULE
, "ppp");
917 if (IS_ERR(ppp_class
)) {
918 err
= PTR_ERR(ppp_class
);
922 /* not a big deal if we fail here :-) */
923 device_create(ppp_class
, NULL
, MKDEV(PPP_MAJOR
, 0), NULL
, "ppp");
928 unregister_chrdev(PPP_MAJOR
, "ppp");
930 unregister_pernet_device(&ppp_net_ops
);
936 * Network interface unit routines.
939 ppp_start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
941 struct ppp
*ppp
= netdev_priv(dev
);
945 npi
= ethertype_to_npindex(ntohs(skb
->protocol
));
949 /* Drop, accept or reject the packet */
950 switch (ppp
->npmode
[npi
]) {
954 /* it would be nice to have a way to tell the network
955 system to queue this one up for later. */
962 /* Put the 2-byte PPP protocol number on the front,
963 making sure there is room for the address and control fields. */
964 if (skb_cow_head(skb
, PPP_HDRLEN
))
967 pp
= skb_push(skb
, 2);
968 proto
= npindex_to_proto
[npi
];
969 put_unaligned_be16(proto
, pp
);
971 skb_queue_tail(&ppp
->file
.xq
, skb
);
972 if (!ppp_xmit_process(ppp
))
973 netif_stop_queue(dev
);
978 ++dev
->stats
.tx_dropped
;
983 ppp_net_ioctl(struct net_device
*dev
, struct ifreq
*ifr
, int cmd
)
985 struct ppp
*ppp
= netdev_priv(dev
);
987 void __user
*addr
= (void __user
*) ifr
->ifr_ifru
.ifru_data
;
988 struct ppp_stats stats
;
989 struct ppp_comp_stats cstats
;
994 ppp_get_stats(ppp
, &stats
);
995 if (copy_to_user(addr
, &stats
, sizeof(stats
)))
1000 case SIOCGPPPCSTATS
:
1001 memset(&cstats
, 0, sizeof(cstats
));
1003 ppp
->xcomp
->comp_stat(ppp
->xc_state
, &cstats
.c
);
1005 ppp
->rcomp
->decomp_stat(ppp
->rc_state
, &cstats
.d
);
1006 if (copy_to_user(addr
, &cstats
, sizeof(cstats
)))
1013 if (copy_to_user(addr
, vers
, strlen(vers
) + 1))
1025 static const struct net_device_ops ppp_netdev_ops
= {
1026 .ndo_start_xmit
= ppp_start_xmit
,
1027 .ndo_do_ioctl
= ppp_net_ioctl
,
1030 static void ppp_setup(struct net_device
*dev
)
1032 dev
->netdev_ops
= &ppp_netdev_ops
;
1033 dev
->hard_header_len
= PPP_HDRLEN
;
1036 dev
->tx_queue_len
= 3;
1037 dev
->type
= ARPHRD_PPP
;
1038 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
1039 dev
->features
|= NETIF_F_NETNS_LOCAL
;
1040 dev
->priv_flags
&= ~IFF_XMIT_DST_RELEASE
;
1044 * Transmit-side routines.
1048 * Called to do any work queued up on the transmit side
1049 * that can now be done.
1052 ppp_xmit_process(struct ppp
*ppp
)
1054 struct sk_buff
*skb
;
1058 if (!ppp
->closing
) {
1060 while (!ppp
->xmit_pending
&&
1061 (skb
= skb_dequeue(&ppp
->file
.xq
)))
1062 ppp_send_frame(ppp
, skb
);
1063 /* If there's no work left to do, tell the core net
1064 code that we can accept some more. */
1065 if (!ppp
->xmit_pending
&& !skb_peek(&ppp
->file
.xq
)) {
1066 netif_wake_queue(ppp
->dev
);
1070 ppp_xmit_unlock(ppp
);
1074 static inline struct sk_buff
*
1075 pad_compress_skb(struct ppp
*ppp
, struct sk_buff
*skb
)
1077 struct sk_buff
*new_skb
;
1079 int new_skb_size
= ppp
->dev
->mtu
+
1080 ppp
->xcomp
->comp_extra
+ ppp
->dev
->hard_header_len
;
1081 int compressor_skb_size
= ppp
->dev
->mtu
+
1082 ppp
->xcomp
->comp_extra
+ PPP_HDRLEN
;
1083 new_skb
= alloc_skb(new_skb_size
, GFP_ATOMIC
);
1085 if (net_ratelimit())
1086 netdev_err(ppp
->dev
, "PPP: no memory (comp pkt)\n");
1089 if (ppp
->dev
->hard_header_len
> PPP_HDRLEN
)
1090 skb_reserve(new_skb
,
1091 ppp
->dev
->hard_header_len
- PPP_HDRLEN
);
1093 /* compressor still expects A/C bytes in hdr */
1094 len
= ppp
->xcomp
->compress(ppp
->xc_state
, skb
->data
- 2,
1095 new_skb
->data
, skb
->len
+ 2,
1096 compressor_skb_size
);
1097 if (len
> 0 && (ppp
->flags
& SC_CCP_UP
)) {
1101 skb_pull(skb
, 2); /* pull off A/C bytes */
1102 } else if (len
== 0) {
1103 /* didn't compress, or CCP not up yet */
1109 * MPPE requires that we do not send unencrypted
1110 * frames. The compressor will return -1 if we
1111 * should drop the frame. We cannot simply test
1112 * the compress_proto because MPPE and MPPC share
1115 if (net_ratelimit())
1116 netdev_err(ppp
->dev
, "ppp: compressor dropped pkt\n");
1125 * Compress and send a frame.
1126 * The caller should have locked the xmit path,
1127 * and xmit_pending should be 0.
1130 ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1132 int proto
= PPP_PROTO(skb
);
1133 struct sk_buff
*new_skb
;
1137 if (proto
< 0x8000) {
1138 #ifdef CONFIG_PPP_FILTER
1139 /* check if we should pass this packet */
1140 /* the filter instructions are constructed assuming
1141 a four-byte PPP header on each packet */
1142 *skb_push(skb
, 2) = 1;
1143 if (ppp
->pass_filter
&&
1144 sk_run_filter(skb
, ppp
->pass_filter
) == 0) {
1146 netdev_printk(KERN_DEBUG
, ppp
->dev
,
1147 "PPP: outbound frame "
1152 /* if this packet passes the active filter, record the time */
1153 if (!(ppp
->active_filter
&&
1154 sk_run_filter(skb
, ppp
->active_filter
) == 0))
1155 ppp
->last_xmit
= jiffies
;
1158 /* for data packets, record the time */
1159 ppp
->last_xmit
= jiffies
;
1160 #endif /* CONFIG_PPP_FILTER */
1163 ++ppp
->dev
->stats
.tx_packets
;
1164 ppp
->dev
->stats
.tx_bytes
+= skb
->len
- 2;
1168 if (!ppp
->vj
|| (ppp
->flags
& SC_COMP_TCP
) == 0)
1170 /* try to do VJ TCP header compression */
1171 new_skb
= alloc_skb(skb
->len
+ ppp
->dev
->hard_header_len
- 2,
1174 netdev_err(ppp
->dev
, "PPP: no memory (VJ comp pkt)\n");
1177 skb_reserve(new_skb
, ppp
->dev
->hard_header_len
- 2);
1179 len
= slhc_compress(ppp
->vj
, cp
, skb
->len
- 2,
1180 new_skb
->data
+ 2, &cp
,
1181 !(ppp
->flags
& SC_NO_TCP_CCID
));
1182 if (cp
== skb
->data
+ 2) {
1183 /* didn't compress */
1186 if (cp
[0] & SL_TYPE_COMPRESSED_TCP
) {
1187 proto
= PPP_VJC_COMP
;
1188 cp
[0] &= ~SL_TYPE_COMPRESSED_TCP
;
1190 proto
= PPP_VJC_UNCOMP
;
1191 cp
[0] = skb
->data
[2];
1195 cp
= skb_put(skb
, len
+ 2);
1202 /* peek at outbound CCP frames */
1203 ppp_ccp_peek(ppp
, skb
, 0);
1207 /* try to do packet compression */
1208 if ((ppp
->xstate
& SC_COMP_RUN
) && ppp
->xc_state
&&
1209 proto
!= PPP_LCP
&& proto
!= PPP_CCP
) {
1210 if (!(ppp
->flags
& SC_CCP_UP
) && (ppp
->flags
& SC_MUST_COMP
)) {
1211 if (net_ratelimit())
1212 netdev_err(ppp
->dev
,
1213 "ppp: compression required but "
1214 "down - pkt dropped.\n");
1217 skb
= pad_compress_skb(ppp
, skb
);
1223 * If we are waiting for traffic (demand dialling),
1224 * queue it up for pppd to receive.
1226 if (ppp
->flags
& SC_LOOP_TRAFFIC
) {
1227 if (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
)
1229 skb_queue_tail(&ppp
->file
.rq
, skb
);
1230 wake_up_interruptible(&ppp
->file
.rwait
);
1234 ppp
->xmit_pending
= skb
;
1240 ++ppp
->dev
->stats
.tx_errors
;
1244 * Try to send the frame in xmit_pending.
1245 * The caller should have the xmit path locked.
1248 ppp_push(struct ppp
*ppp
)
1250 struct list_head
*list
;
1251 struct channel
*pch
;
1252 struct sk_buff
*skb
= ppp
->xmit_pending
;
1257 list
= &ppp
->channels
;
1258 if (list_empty(list
)) {
1259 /* nowhere to send the packet, just drop it */
1260 ppp
->xmit_pending
= NULL
;
1265 if ((ppp
->flags
& SC_MULTILINK
) == 0) {
1266 /* not doing multilink: send it down the first channel */
1268 pch
= list_entry(list
, struct channel
, clist
);
1270 spin_lock_bh(&pch
->downl
);
1272 if (pch
->chan
->ops
->start_xmit(pch
->chan
, skb
))
1273 ppp
->xmit_pending
= NULL
;
1275 /* channel got unregistered */
1277 ppp
->xmit_pending
= NULL
;
1279 spin_unlock_bh(&pch
->downl
);
1283 #ifdef CONFIG_PPP_MULTILINK
1284 /* Multilink: fragment the packet over as many links
1285 as can take the packet at the moment. */
1286 if (!ppp_mp_explode(ppp
, skb
))
1288 #endif /* CONFIG_PPP_MULTILINK */
1290 ppp
->xmit_pending
= NULL
;
1294 #ifdef CONFIG_PPP_MULTILINK
1295 static bool mp_protocol_compress __read_mostly
= true;
1296 module_param(mp_protocol_compress
, bool, S_IRUGO
| S_IWUSR
);
1297 MODULE_PARM_DESC(mp_protocol_compress
,
1298 "compress protocol id in multilink fragments");
1301 * Divide a packet to be transmitted into fragments and
1302 * send them out the individual links.
1304 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
)
1307 int i
, bits
, hdrlen
, mtu
;
1309 int navail
, nfree
, nzero
;
1313 unsigned char *p
, *q
;
1314 struct list_head
*list
;
1315 struct channel
*pch
;
1316 struct sk_buff
*frag
;
1317 struct ppp_channel
*chan
;
1319 totspeed
= 0; /*total bitrate of the bundle*/
1320 nfree
= 0; /* # channels which have no packet already queued */
1321 navail
= 0; /* total # of usable channels (not deregistered) */
1322 nzero
= 0; /* number of channels with zero speed associated*/
1323 totfree
= 0; /*total # of channels available and
1324 *having no queued packets before
1325 *starting the fragmentation*/
1327 hdrlen
= (ppp
->flags
& SC_MP_XSHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1329 list_for_each_entry(pch
, &ppp
->channels
, clist
) {
1333 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 */
1365 if (*p
== 0 && mp_protocol_compress
) {
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
1435 if (pch
->speed
== 0) {
1442 flen
= (((totfree
- nzero
)*(totlen
+ hdrlen
*totfree
)) /
1443 ((totspeed
*totfree
)/pch
->speed
)) - hdrlen
;
1445 flen
+= ((totfree
- nzero
)*pch
->speed
)/totspeed
;
1446 nbigger
-= ((totfree
- nzero
)*pch
->speed
)/
1454 *check if we are on the last channel or
1455 *we exceded the length of the data to
1458 if ((nfree
<= 0) || (flen
> len
))
1461 *it is not worth to tx on slow channels:
1462 *in that case from the resulting flen according to the
1463 *above formula will be equal or less than zero.
1464 *Skip the channel in this case
1468 spin_unlock_bh(&pch
->downl
);
1473 * hdrlen includes the 2-byte PPP protocol field, but the
1474 * MTU counts only the payload excluding the protocol field.
1475 * (RFC1661 Section 2)
1477 mtu
= pch
->chan
->mtu
- (hdrlen
- 2);
1484 frag
= alloc_skb(flen
+ hdrlen
+ (flen
== 0), GFP_ATOMIC
);
1487 q
= skb_put(frag
, flen
+ hdrlen
);
1489 /* make the MP header */
1490 put_unaligned_be16(PPP_MP
, q
);
1491 if (ppp
->flags
& SC_MP_XSHORTSEQ
) {
1492 q
[2] = bits
+ ((ppp
->nxseq
>> 8) & 0xf);
1496 q
[3] = ppp
->nxseq
>> 16;
1497 q
[4] = ppp
->nxseq
>> 8;
1501 memcpy(q
+ hdrlen
, p
, flen
);
1503 /* try to send it down the channel */
1505 if (!skb_queue_empty(&pch
->file
.xq
) ||
1506 !chan
->ops
->start_xmit(chan
, frag
))
1507 skb_queue_tail(&pch
->file
.xq
, frag
);
1513 spin_unlock_bh(&pch
->downl
);
1520 spin_unlock_bh(&pch
->downl
);
1522 netdev_err(ppp
->dev
, "PPP: no memory (fragment)\n");
1523 ++ppp
->dev
->stats
.tx_errors
;
1525 return 1; /* abandon the frame */
1527 #endif /* CONFIG_PPP_MULTILINK */
1530 * Try to send data out on a channel.
1533 ppp_channel_push(struct channel
*pch
)
1535 struct sk_buff
*skb
;
1538 spin_lock_bh(&pch
->downl
);
1540 while (!skb_queue_empty(&pch
->file
.xq
)) {
1541 skb
= skb_dequeue(&pch
->file
.xq
);
1542 if (!pch
->chan
->ops
->start_xmit(pch
->chan
, skb
)) {
1543 /* put the packet back and try again later */
1544 skb_queue_head(&pch
->file
.xq
, skb
);
1549 /* channel got deregistered */
1550 skb_queue_purge(&pch
->file
.xq
);
1552 spin_unlock_bh(&pch
->downl
);
1553 /* see if there is anything from the attached unit to be sent */
1554 if (skb_queue_empty(&pch
->file
.xq
)) {
1555 read_lock_bh(&pch
->upl
);
1558 ppp_xmit_process(ppp
);
1559 read_unlock_bh(&pch
->upl
);
1564 * Receive-side routines.
1567 struct ppp_mp_skb_parm
{
1571 #define PPP_MP_CB(skb) ((struct ppp_mp_skb_parm *)((skb)->cb))
1574 ppp_do_recv(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1578 ppp_receive_frame(ppp
, skb
, pch
);
1581 ppp_recv_unlock(ppp
);
1585 ppp_input(struct ppp_channel
*chan
, struct sk_buff
*skb
)
1587 struct channel
*pch
= chan
->ppp
;
1595 read_lock_bh(&pch
->upl
);
1596 if (!pskb_may_pull(skb
, 2)) {
1599 ++pch
->ppp
->dev
->stats
.rx_length_errors
;
1600 ppp_receive_error(pch
->ppp
);
1605 proto
= PPP_PROTO(skb
);
1606 if (!pch
->ppp
|| proto
>= 0xc000 || proto
== PPP_CCPFRAG
) {
1607 /* put it on the channel queue */
1608 skb_queue_tail(&pch
->file
.rq
, skb
);
1609 /* drop old frames if queue too long */
1610 while (pch
->file
.rq
.qlen
> PPP_MAX_RQLEN
&&
1611 (skb
= skb_dequeue(&pch
->file
.rq
)))
1613 wake_up_interruptible(&pch
->file
.rwait
);
1615 ppp_do_recv(pch
->ppp
, skb
, pch
);
1619 read_unlock_bh(&pch
->upl
);
1622 /* Put a 0-length skb in the receive queue as an error indication */
1624 ppp_input_error(struct ppp_channel
*chan
, int code
)
1626 struct channel
*pch
= chan
->ppp
;
1627 struct sk_buff
*skb
;
1632 read_lock_bh(&pch
->upl
);
1634 skb
= alloc_skb(0, GFP_ATOMIC
);
1636 skb
->len
= 0; /* probably unnecessary */
1638 ppp_do_recv(pch
->ppp
, skb
, pch
);
1641 read_unlock_bh(&pch
->upl
);
1645 * We come in here to process a received frame.
1646 * The receive side of the ppp unit is locked.
1649 ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1651 /* note: a 0-length skb is used as an error indication */
1653 #ifdef CONFIG_PPP_MULTILINK
1654 /* XXX do channel-level decompression here */
1655 if (PPP_PROTO(skb
) == PPP_MP
)
1656 ppp_receive_mp_frame(ppp
, skb
, pch
);
1658 #endif /* CONFIG_PPP_MULTILINK */
1659 ppp_receive_nonmp_frame(ppp
, skb
);
1662 ppp_receive_error(ppp
);
1667 ppp_receive_error(struct ppp
*ppp
)
1669 ++ppp
->dev
->stats
.rx_errors
;
1675 ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1678 int proto
, len
, npi
;
1681 * Decompress the frame, if compressed.
1682 * Note that some decompressors need to see uncompressed frames
1683 * that come in as well as compressed frames.
1685 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
) &&
1686 (ppp
->rstate
& (SC_DC_FERROR
| SC_DC_ERROR
)) == 0)
1687 skb
= ppp_decompress_frame(ppp
, skb
);
1689 if (ppp
->flags
& SC_MUST_COMP
&& ppp
->rstate
& SC_DC_FERROR
)
1692 proto
= PPP_PROTO(skb
);
1695 /* decompress VJ compressed packets */
1696 if (!ppp
->vj
|| (ppp
->flags
& SC_REJ_COMP_TCP
))
1699 if (skb_tailroom(skb
) < 124 || skb_cloned(skb
)) {
1700 /* copy to a new sk_buff with more tailroom */
1701 ns
= dev_alloc_skb(skb
->len
+ 128);
1703 netdev_err(ppp
->dev
, "PPP: no memory "
1708 skb_copy_bits(skb
, 0, skb_put(ns
, skb
->len
), skb
->len
);
1713 skb
->ip_summed
= CHECKSUM_NONE
;
1715 len
= slhc_uncompress(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2);
1717 netdev_printk(KERN_DEBUG
, ppp
->dev
,
1718 "PPP: VJ decompression error\n");
1723 skb_put(skb
, len
- skb
->len
);
1724 else if (len
< skb
->len
)
1729 case PPP_VJC_UNCOMP
:
1730 if (!ppp
->vj
|| (ppp
->flags
& SC_REJ_COMP_TCP
))
1733 /* Until we fix the decompressor need to make sure
1734 * data portion is linear.
1736 if (!pskb_may_pull(skb
, skb
->len
))
1739 if (slhc_remember(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2) <= 0) {
1740 netdev_err(ppp
->dev
, "PPP: VJ uncompressed error\n");
1747 ppp_ccp_peek(ppp
, skb
, 1);
1751 ++ppp
->dev
->stats
.rx_packets
;
1752 ppp
->dev
->stats
.rx_bytes
+= skb
->len
- 2;
1754 npi
= proto_to_npindex(proto
);
1756 /* control or unknown frame - pass it to pppd */
1757 skb_queue_tail(&ppp
->file
.rq
, skb
);
1758 /* limit queue length by dropping old frames */
1759 while (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
&&
1760 (skb
= skb_dequeue(&ppp
->file
.rq
)))
1762 /* wake up any process polling or blocking on read */
1763 wake_up_interruptible(&ppp
->file
.rwait
);
1766 /* network protocol frame - give it to the kernel */
1768 #ifdef CONFIG_PPP_FILTER
1769 /* check if the packet passes the pass and active filters */
1770 /* the filter instructions are constructed assuming
1771 a four-byte PPP header on each packet */
1772 if (ppp
->pass_filter
|| ppp
->active_filter
) {
1773 if (skb_cloned(skb
) &&
1774 pskb_expand_head(skb
, 0, 0, GFP_ATOMIC
))
1777 *skb_push(skb
, 2) = 0;
1778 if (ppp
->pass_filter
&&
1779 sk_run_filter(skb
, ppp
->pass_filter
) == 0) {
1781 netdev_printk(KERN_DEBUG
, ppp
->dev
,
1782 "PPP: inbound frame "
1787 if (!(ppp
->active_filter
&&
1788 sk_run_filter(skb
, ppp
->active_filter
) == 0))
1789 ppp
->last_recv
= jiffies
;
1792 #endif /* CONFIG_PPP_FILTER */
1793 ppp
->last_recv
= jiffies
;
1795 if ((ppp
->dev
->flags
& IFF_UP
) == 0 ||
1796 ppp
->npmode
[npi
] != NPMODE_PASS
) {
1799 /* chop off protocol */
1800 skb_pull_rcsum(skb
, 2);
1801 skb
->dev
= ppp
->dev
;
1802 skb
->protocol
= htons(npindex_to_ethertype
[npi
]);
1803 skb_reset_mac_header(skb
);
1811 ppp_receive_error(ppp
);
1814 static struct sk_buff
*
1815 ppp_decompress_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1817 int proto
= PPP_PROTO(skb
);
1821 /* Until we fix all the decompressor's need to make sure
1822 * data portion is linear.
1824 if (!pskb_may_pull(skb
, skb
->len
))
1827 if (proto
== PPP_COMP
) {
1830 switch(ppp
->rcomp
->compress_proto
) {
1832 obuff_size
= ppp
->mru
+ PPP_HDRLEN
+ 1;
1835 obuff_size
= ppp
->mru
+ PPP_HDRLEN
;
1839 ns
= dev_alloc_skb(obuff_size
);
1841 netdev_err(ppp
->dev
, "ppp_decompress_frame: "
1845 /* the decompressor still expects the A/C bytes in the hdr */
1846 len
= ppp
->rcomp
->decompress(ppp
->rc_state
, skb
->data
- 2,
1847 skb
->len
+ 2, ns
->data
, obuff_size
);
1849 /* Pass the compressed frame to pppd as an
1850 error indication. */
1851 if (len
== DECOMP_FATALERROR
)
1852 ppp
->rstate
|= SC_DC_FERROR
;
1860 skb_pull(skb
, 2); /* pull off the A/C bytes */
1863 /* Uncompressed frame - pass to decompressor so it
1864 can update its dictionary if necessary. */
1865 if (ppp
->rcomp
->incomp
)
1866 ppp
->rcomp
->incomp(ppp
->rc_state
, skb
->data
- 2,
1873 ppp
->rstate
|= SC_DC_ERROR
;
1874 ppp_receive_error(ppp
);
1878 #ifdef CONFIG_PPP_MULTILINK
1880 * Receive a multilink frame.
1881 * We put it on the reconstruction queue and then pull off
1882 * as many completed frames as we can.
1885 ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1889 int mphdrlen
= (ppp
->flags
& SC_MP_SHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1891 if (!pskb_may_pull(skb
, mphdrlen
+ 1) || ppp
->mrru
== 0)
1892 goto err
; /* no good, throw it away */
1894 /* Decode sequence number and begin/end bits */
1895 if (ppp
->flags
& SC_MP_SHORTSEQ
) {
1896 seq
= ((skb
->data
[2] & 0x0f) << 8) | skb
->data
[3];
1899 seq
= (skb
->data
[3] << 16) | (skb
->data
[4] << 8)| skb
->data
[5];
1902 PPP_MP_CB(skb
)->BEbits
= skb
->data
[2];
1903 skb_pull(skb
, mphdrlen
); /* pull off PPP and MP headers */
1906 * Do protocol ID decompression on the first fragment of each packet.
1908 if ((PPP_MP_CB(skb
)->BEbits
& B
) && (skb
->data
[0] & 1))
1909 *skb_push(skb
, 1) = 0;
1912 * Expand sequence number to 32 bits, making it as close
1913 * as possible to ppp->minseq.
1915 seq
|= ppp
->minseq
& ~mask
;
1916 if ((int)(ppp
->minseq
- seq
) > (int)(mask
>> 1))
1918 else if ((int)(seq
- ppp
->minseq
) > (int)(mask
>> 1))
1919 seq
-= mask
+ 1; /* should never happen */
1920 PPP_MP_CB(skb
)->sequence
= seq
;
1924 * If this packet comes before the next one we were expecting,
1927 if (seq_before(seq
, ppp
->nextseq
)) {
1929 ++ppp
->dev
->stats
.rx_dropped
;
1930 ppp_receive_error(ppp
);
1935 * Reevaluate minseq, the minimum over all channels of the
1936 * last sequence number received on each channel. Because of
1937 * the increasing sequence number rule, we know that any fragment
1938 * before `minseq' which hasn't arrived is never going to arrive.
1939 * The list of channels can't change because we have the receive
1940 * side of the ppp unit locked.
1942 list_for_each_entry(ch
, &ppp
->channels
, clist
) {
1943 if (seq_before(ch
->lastseq
, seq
))
1946 if (seq_before(ppp
->minseq
, seq
))
1949 /* Put the fragment on the reconstruction queue */
1950 ppp_mp_insert(ppp
, skb
);
1952 /* If the queue is getting long, don't wait any longer for packets
1953 before the start of the queue. */
1954 if (skb_queue_len(&ppp
->mrq
) >= PPP_MP_MAX_QLEN
) {
1955 struct sk_buff
*mskb
= skb_peek(&ppp
->mrq
);
1956 if (seq_before(ppp
->minseq
, PPP_MP_CB(mskb
)->sequence
))
1957 ppp
->minseq
= PPP_MP_CB(mskb
)->sequence
;
1960 /* Pull completed packets off the queue and receive them. */
1961 while ((skb
= ppp_mp_reconstruct(ppp
))) {
1962 if (pskb_may_pull(skb
, 2))
1963 ppp_receive_nonmp_frame(ppp
, skb
);
1965 ++ppp
->dev
->stats
.rx_length_errors
;
1967 ppp_receive_error(ppp
);
1975 ppp_receive_error(ppp
);
1979 * Insert a fragment on the MP reconstruction queue.
1980 * The queue is ordered by increasing sequence number.
1983 ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
)
1986 struct sk_buff_head
*list
= &ppp
->mrq
;
1987 u32 seq
= PPP_MP_CB(skb
)->sequence
;
1989 /* N.B. we don't need to lock the list lock because we have the
1990 ppp unit receive-side lock. */
1991 skb_queue_walk(list
, p
) {
1992 if (seq_before(seq
, PPP_MP_CB(p
)->sequence
))
1995 __skb_queue_before(list
, p
, skb
);
1999 * Reconstruct a packet from the MP fragment queue.
2000 * We go through increasing sequence numbers until we find a
2001 * complete packet, or we get to the sequence number for a fragment
2002 * which hasn't arrived but might still do so.
2004 static struct sk_buff
*
2005 ppp_mp_reconstruct(struct ppp
*ppp
)
2007 u32 seq
= ppp
->nextseq
;
2008 u32 minseq
= ppp
->minseq
;
2009 struct sk_buff_head
*list
= &ppp
->mrq
;
2010 struct sk_buff
*p
, *tmp
;
2011 struct sk_buff
*head
, *tail
;
2012 struct sk_buff
*skb
= NULL
;
2013 int lost
= 0, len
= 0;
2015 if (ppp
->mrru
== 0) /* do nothing until mrru is set */
2019 skb_queue_walk_safe(list
, p
, tmp
) {
2021 if (seq_before(PPP_MP_CB(p
)->sequence
, seq
)) {
2022 /* this can't happen, anyway ignore the skb */
2023 netdev_err(ppp
->dev
, "ppp_mp_reconstruct bad "
2025 PPP_MP_CB(p
)->sequence
, seq
);
2026 __skb_unlink(p
, list
);
2030 if (PPP_MP_CB(p
)->sequence
!= seq
) {
2032 /* Fragment `seq' is missing. If it is after
2033 minseq, it might arrive later, so stop here. */
2034 if (seq_after(seq
, minseq
))
2036 /* Fragment `seq' is lost, keep going. */
2039 seq
= seq_before(minseq
, PPP_MP_CB(p
)->sequence
)?
2040 minseq
+ 1: PPP_MP_CB(p
)->sequence
;
2043 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2044 "lost frag %u..%u\n",
2051 * At this point we know that all the fragments from
2052 * ppp->nextseq to seq are either present or lost.
2053 * Also, there are no complete packets in the queue
2054 * that have no missing fragments and end before this
2058 /* B bit set indicates this fragment starts a packet */
2059 if (PPP_MP_CB(p
)->BEbits
& B
) {
2067 /* Got a complete packet yet? */
2068 if (lost
== 0 && (PPP_MP_CB(p
)->BEbits
& E
) &&
2069 (PPP_MP_CB(head
)->BEbits
& B
)) {
2070 if (len
> ppp
->mrru
+ 2) {
2071 ++ppp
->dev
->stats
.rx_length_errors
;
2072 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2073 "PPP: reconstructed packet"
2074 " is too long (%d)\n", len
);
2079 ppp
->nextseq
= seq
+ 1;
2083 * If this is the ending fragment of a packet,
2084 * and we haven't found a complete valid packet yet,
2085 * we can discard up to and including this fragment.
2087 if (PPP_MP_CB(p
)->BEbits
& E
) {
2088 struct sk_buff
*tmp2
;
2090 skb_queue_reverse_walk_from_safe(list
, p
, tmp2
) {
2092 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2093 "discarding frag %u\n",
2094 PPP_MP_CB(p
)->sequence
);
2095 __skb_unlink(p
, list
);
2098 head
= skb_peek(list
);
2105 /* If we have a complete packet, copy it all into one skb. */
2107 /* If we have discarded any fragments,
2108 signal a receive error. */
2109 if (PPP_MP_CB(head
)->sequence
!= ppp
->nextseq
) {
2110 skb_queue_walk_safe(list
, p
, tmp
) {
2114 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2115 "discarding frag %u\n",
2116 PPP_MP_CB(p
)->sequence
);
2117 __skb_unlink(p
, list
);
2122 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2123 " missed pkts %u..%u\n",
2125 PPP_MP_CB(head
)->sequence
-1);
2126 ++ppp
->dev
->stats
.rx_dropped
;
2127 ppp_receive_error(ppp
);
2132 struct sk_buff
**fragpp
= &skb_shinfo(skb
)->frag_list
;
2133 p
= skb_queue_next(list
, head
);
2134 __skb_unlink(skb
, list
);
2135 skb_queue_walk_from_safe(list
, p
, tmp
) {
2136 __skb_unlink(p
, list
);
2142 skb
->data_len
+= p
->len
;
2143 skb
->truesize
+= p
->truesize
;
2149 __skb_unlink(skb
, list
);
2152 ppp
->nextseq
= PPP_MP_CB(tail
)->sequence
+ 1;
2157 #endif /* CONFIG_PPP_MULTILINK */
2160 * Channel interface.
2163 /* Create a new, unattached ppp channel. */
2164 int ppp_register_channel(struct ppp_channel
*chan
)
2166 return ppp_register_net_channel(current
->nsproxy
->net_ns
, chan
);
2169 /* Create a new, unattached ppp channel for specified net. */
2170 int ppp_register_net_channel(struct net
*net
, struct ppp_channel
*chan
)
2172 struct channel
*pch
;
2175 pch
= kzalloc(sizeof(struct channel
), GFP_KERNEL
);
2179 pn
= ppp_pernet(net
);
2183 pch
->chan_net
= net
;
2185 init_ppp_file(&pch
->file
, CHANNEL
);
2186 pch
->file
.hdrlen
= chan
->hdrlen
;
2187 #ifdef CONFIG_PPP_MULTILINK
2189 #endif /* CONFIG_PPP_MULTILINK */
2190 init_rwsem(&pch
->chan_sem
);
2191 spin_lock_init(&pch
->downl
);
2192 rwlock_init(&pch
->upl
);
2194 spin_lock_bh(&pn
->all_channels_lock
);
2195 pch
->file
.index
= ++pn
->last_channel_index
;
2196 list_add(&pch
->list
, &pn
->new_channels
);
2197 atomic_inc(&channel_count
);
2198 spin_unlock_bh(&pn
->all_channels_lock
);
2204 * Return the index of a channel.
2206 int ppp_channel_index(struct ppp_channel
*chan
)
2208 struct channel
*pch
= chan
->ppp
;
2211 return pch
->file
.index
;
2216 * Return the PPP unit number to which a channel is connected.
2218 int ppp_unit_number(struct ppp_channel
*chan
)
2220 struct channel
*pch
= chan
->ppp
;
2224 read_lock_bh(&pch
->upl
);
2226 unit
= pch
->ppp
->file
.index
;
2227 read_unlock_bh(&pch
->upl
);
2233 * Return the PPP device interface name of a channel.
2235 char *ppp_dev_name(struct ppp_channel
*chan
)
2237 struct channel
*pch
= chan
->ppp
;
2241 read_lock_bh(&pch
->upl
);
2242 if (pch
->ppp
&& pch
->ppp
->dev
)
2243 name
= pch
->ppp
->dev
->name
;
2244 read_unlock_bh(&pch
->upl
);
2251 * Disconnect a channel from the generic layer.
2252 * This must be called in process context.
2255 ppp_unregister_channel(struct ppp_channel
*chan
)
2257 struct channel
*pch
= chan
->ppp
;
2261 return; /* should never happen */
2266 * This ensures that we have returned from any calls into the
2267 * the channel's start_xmit or ioctl routine before we proceed.
2269 down_write(&pch
->chan_sem
);
2270 spin_lock_bh(&pch
->downl
);
2272 spin_unlock_bh(&pch
->downl
);
2273 up_write(&pch
->chan_sem
);
2274 ppp_disconnect_channel(pch
);
2276 pn
= ppp_pernet(pch
->chan_net
);
2277 spin_lock_bh(&pn
->all_channels_lock
);
2278 list_del(&pch
->list
);
2279 spin_unlock_bh(&pn
->all_channels_lock
);
2282 wake_up_interruptible(&pch
->file
.rwait
);
2283 if (atomic_dec_and_test(&pch
->file
.refcnt
))
2284 ppp_destroy_channel(pch
);
2288 * Callback from a channel when it can accept more to transmit.
2289 * This should be called at BH/softirq level, not interrupt level.
2292 ppp_output_wakeup(struct ppp_channel
*chan
)
2294 struct channel
*pch
= chan
->ppp
;
2298 ppp_channel_push(pch
);
2302 * Compression control.
2305 /* Process the PPPIOCSCOMPRESS ioctl. */
2307 ppp_set_compress(struct ppp
*ppp
, unsigned long arg
)
2310 struct compressor
*cp
, *ocomp
;
2311 struct ppp_option_data data
;
2312 void *state
, *ostate
;
2313 unsigned char ccp_option
[CCP_MAX_OPTION_LENGTH
];
2316 if (copy_from_user(&data
, (void __user
*) arg
, sizeof(data
)) ||
2317 (data
.length
<= CCP_MAX_OPTION_LENGTH
&&
2318 copy_from_user(ccp_option
, (void __user
*) data
.ptr
, data
.length
)))
2321 if (data
.length
> CCP_MAX_OPTION_LENGTH
||
2322 ccp_option
[1] < 2 || ccp_option
[1] > data
.length
)
2325 cp
= try_then_request_module(
2326 find_compressor(ccp_option
[0]),
2327 "ppp-compress-%d", ccp_option
[0]);
2332 if (data
.transmit
) {
2333 state
= cp
->comp_alloc(ccp_option
, data
.length
);
2336 ppp
->xstate
&= ~SC_COMP_RUN
;
2338 ostate
= ppp
->xc_state
;
2340 ppp
->xc_state
= state
;
2341 ppp_xmit_unlock(ppp
);
2343 ocomp
->comp_free(ostate
);
2344 module_put(ocomp
->owner
);
2348 module_put(cp
->owner
);
2351 state
= cp
->decomp_alloc(ccp_option
, data
.length
);
2354 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2356 ostate
= ppp
->rc_state
;
2358 ppp
->rc_state
= state
;
2359 ppp_recv_unlock(ppp
);
2361 ocomp
->decomp_free(ostate
);
2362 module_put(ocomp
->owner
);
2366 module_put(cp
->owner
);
2374 * Look at a CCP packet and update our state accordingly.
2375 * We assume the caller has the xmit or recv path locked.
2378 ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
)
2383 if (!pskb_may_pull(skb
, CCP_HDRLEN
+ 2))
2384 return; /* no header */
2387 switch (CCP_CODE(dp
)) {
2390 /* A ConfReq starts negotiation of compression
2391 * in one direction of transmission,
2392 * and hence brings it down...but which way?
2395 * A ConfReq indicates what the sender would like to receive
2398 /* He is proposing what I should send */
2399 ppp
->xstate
&= ~SC_COMP_RUN
;
2401 /* I am proposing to what he should send */
2402 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2409 * CCP is going down, both directions of transmission
2411 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2412 ppp
->xstate
&= ~SC_COMP_RUN
;
2416 if ((ppp
->flags
& (SC_CCP_OPEN
| SC_CCP_UP
)) != SC_CCP_OPEN
)
2418 len
= CCP_LENGTH(dp
);
2419 if (!pskb_may_pull(skb
, len
+ 2))
2420 return; /* too short */
2423 if (len
< CCP_OPT_MINLEN
|| len
< CCP_OPT_LENGTH(dp
))
2426 /* we will start receiving compressed packets */
2429 if (ppp
->rcomp
->decomp_init(ppp
->rc_state
, dp
, len
,
2430 ppp
->file
.index
, 0, ppp
->mru
, ppp
->debug
)) {
2431 ppp
->rstate
|= SC_DECOMP_RUN
;
2432 ppp
->rstate
&= ~(SC_DC_ERROR
| SC_DC_FERROR
);
2435 /* we will soon start sending compressed packets */
2438 if (ppp
->xcomp
->comp_init(ppp
->xc_state
, dp
, len
,
2439 ppp
->file
.index
, 0, ppp
->debug
))
2440 ppp
->xstate
|= SC_COMP_RUN
;
2445 /* reset the [de]compressor */
2446 if ((ppp
->flags
& SC_CCP_UP
) == 0)
2449 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
)) {
2450 ppp
->rcomp
->decomp_reset(ppp
->rc_state
);
2451 ppp
->rstate
&= ~SC_DC_ERROR
;
2454 if (ppp
->xc_state
&& (ppp
->xstate
& SC_COMP_RUN
))
2455 ppp
->xcomp
->comp_reset(ppp
->xc_state
);
2461 /* Free up compression resources. */
2463 ppp_ccp_closed(struct ppp
*ppp
)
2465 void *xstate
, *rstate
;
2466 struct compressor
*xcomp
, *rcomp
;
2469 ppp
->flags
&= ~(SC_CCP_OPEN
| SC_CCP_UP
);
2472 xstate
= ppp
->xc_state
;
2473 ppp
->xc_state
= NULL
;
2476 rstate
= ppp
->rc_state
;
2477 ppp
->rc_state
= NULL
;
2481 xcomp
->comp_free(xstate
);
2482 module_put(xcomp
->owner
);
2485 rcomp
->decomp_free(rstate
);
2486 module_put(rcomp
->owner
);
2490 /* List of compressors. */
2491 static LIST_HEAD(compressor_list
);
2492 static DEFINE_SPINLOCK(compressor_list_lock
);
2494 struct compressor_entry
{
2495 struct list_head list
;
2496 struct compressor
*comp
;
2499 static struct compressor_entry
*
2500 find_comp_entry(int proto
)
2502 struct compressor_entry
*ce
;
2504 list_for_each_entry(ce
, &compressor_list
, list
) {
2505 if (ce
->comp
->compress_proto
== proto
)
2511 /* Register a compressor */
2513 ppp_register_compressor(struct compressor
*cp
)
2515 struct compressor_entry
*ce
;
2517 spin_lock(&compressor_list_lock
);
2519 if (find_comp_entry(cp
->compress_proto
))
2522 ce
= kmalloc(sizeof(struct compressor_entry
), GFP_ATOMIC
);
2527 list_add(&ce
->list
, &compressor_list
);
2529 spin_unlock(&compressor_list_lock
);
2533 /* Unregister a compressor */
2535 ppp_unregister_compressor(struct compressor
*cp
)
2537 struct compressor_entry
*ce
;
2539 spin_lock(&compressor_list_lock
);
2540 ce
= find_comp_entry(cp
->compress_proto
);
2541 if (ce
&& ce
->comp
== cp
) {
2542 list_del(&ce
->list
);
2545 spin_unlock(&compressor_list_lock
);
2548 /* Find a compressor. */
2549 static struct compressor
*
2550 find_compressor(int type
)
2552 struct compressor_entry
*ce
;
2553 struct compressor
*cp
= NULL
;
2555 spin_lock(&compressor_list_lock
);
2556 ce
= find_comp_entry(type
);
2559 if (!try_module_get(cp
->owner
))
2562 spin_unlock(&compressor_list_lock
);
2567 * Miscelleneous stuff.
2571 ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
)
2573 struct slcompress
*vj
= ppp
->vj
;
2575 memset(st
, 0, sizeof(*st
));
2576 st
->p
.ppp_ipackets
= ppp
->dev
->stats
.rx_packets
;
2577 st
->p
.ppp_ierrors
= ppp
->dev
->stats
.rx_errors
;
2578 st
->p
.ppp_ibytes
= ppp
->dev
->stats
.rx_bytes
;
2579 st
->p
.ppp_opackets
= ppp
->dev
->stats
.tx_packets
;
2580 st
->p
.ppp_oerrors
= ppp
->dev
->stats
.tx_errors
;
2581 st
->p
.ppp_obytes
= ppp
->dev
->stats
.tx_bytes
;
2584 st
->vj
.vjs_packets
= vj
->sls_o_compressed
+ vj
->sls_o_uncompressed
;
2585 st
->vj
.vjs_compressed
= vj
->sls_o_compressed
;
2586 st
->vj
.vjs_searches
= vj
->sls_o_searches
;
2587 st
->vj
.vjs_misses
= vj
->sls_o_misses
;
2588 st
->vj
.vjs_errorin
= vj
->sls_i_error
;
2589 st
->vj
.vjs_tossed
= vj
->sls_i_tossed
;
2590 st
->vj
.vjs_uncompressedin
= vj
->sls_i_uncompressed
;
2591 st
->vj
.vjs_compressedin
= vj
->sls_i_compressed
;
2595 * Stuff for handling the lists of ppp units and channels
2596 * and for initialization.
2600 * Create a new ppp interface unit. Fails if it can't allocate memory
2601 * or if there is already a unit with the requested number.
2602 * unit == -1 means allocate a new number.
2605 ppp_create_interface(struct net
*net
, int unit
, int *retp
)
2609 struct net_device
*dev
= NULL
;
2613 dev
= alloc_netdev(sizeof(struct ppp
), "", ppp_setup
);
2617 pn
= ppp_pernet(net
);
2619 ppp
= netdev_priv(dev
);
2622 init_ppp_file(&ppp
->file
, INTERFACE
);
2623 ppp
->file
.hdrlen
= PPP_HDRLEN
- 2; /* don't count proto bytes */
2624 for (i
= 0; i
< NUM_NP
; ++i
)
2625 ppp
->npmode
[i
] = NPMODE_PASS
;
2626 INIT_LIST_HEAD(&ppp
->channels
);
2627 spin_lock_init(&ppp
->rlock
);
2628 spin_lock_init(&ppp
->wlock
);
2629 #ifdef CONFIG_PPP_MULTILINK
2631 skb_queue_head_init(&ppp
->mrq
);
2632 #endif /* CONFIG_PPP_MULTILINK */
2635 * drum roll: don't forget to set
2636 * the net device is belong to
2638 dev_net_set(dev
, net
);
2640 mutex_lock(&pn
->all_ppp_mutex
);
2643 unit
= unit_get(&pn
->units_idr
, ppp
);
2650 if (unit_find(&pn
->units_idr
, unit
))
2651 goto out2
; /* unit already exists */
2653 * if caller need a specified unit number
2654 * lets try to satisfy him, otherwise --
2655 * he should better ask us for new unit number
2657 * NOTE: yes I know that returning EEXIST it's not
2658 * fair but at least pppd will ask us to allocate
2659 * new unit in this case so user is happy :)
2661 unit
= unit_set(&pn
->units_idr
, ppp
, unit
);
2666 /* Initialize the new ppp unit */
2667 ppp
->file
.index
= unit
;
2668 sprintf(dev
->name
, "ppp%d", unit
);
2670 ret
= register_netdev(dev
);
2672 unit_put(&pn
->units_idr
, unit
);
2673 netdev_err(ppp
->dev
, "PPP: couldn't register device %s (%d)\n",
2680 atomic_inc(&ppp_unit_count
);
2681 mutex_unlock(&pn
->all_ppp_mutex
);
2687 mutex_unlock(&pn
->all_ppp_mutex
);
2695 * Initialize a ppp_file structure.
2698 init_ppp_file(struct ppp_file
*pf
, int kind
)
2701 skb_queue_head_init(&pf
->xq
);
2702 skb_queue_head_init(&pf
->rq
);
2703 atomic_set(&pf
->refcnt
, 1);
2704 init_waitqueue_head(&pf
->rwait
);
2708 * Take down a ppp interface unit - called when the owning file
2709 * (the one that created the unit) is closed or detached.
2711 static void ppp_shutdown_interface(struct ppp
*ppp
)
2715 pn
= ppp_pernet(ppp
->ppp_net
);
2716 mutex_lock(&pn
->all_ppp_mutex
);
2718 /* This will call dev_close() for us. */
2720 if (!ppp
->closing
) {
2723 unregister_netdev(ppp
->dev
);
2724 unit_put(&pn
->units_idr
, ppp
->file
.index
);
2730 wake_up_interruptible(&ppp
->file
.rwait
);
2732 mutex_unlock(&pn
->all_ppp_mutex
);
2736 * Free the memory used by a ppp unit. This is only called once
2737 * there are no channels connected to the unit and no file structs
2738 * that reference the unit.
2740 static void ppp_destroy_interface(struct ppp
*ppp
)
2742 atomic_dec(&ppp_unit_count
);
2744 if (!ppp
->file
.dead
|| ppp
->n_channels
) {
2745 /* "can't happen" */
2746 netdev_err(ppp
->dev
, "ppp: destroying ppp struct %p "
2747 "but dead=%d n_channels=%d !\n",
2748 ppp
, ppp
->file
.dead
, ppp
->n_channels
);
2752 ppp_ccp_closed(ppp
);
2757 skb_queue_purge(&ppp
->file
.xq
);
2758 skb_queue_purge(&ppp
->file
.rq
);
2759 #ifdef CONFIG_PPP_MULTILINK
2760 skb_queue_purge(&ppp
->mrq
);
2761 #endif /* CONFIG_PPP_MULTILINK */
2762 #ifdef CONFIG_PPP_FILTER
2763 kfree(ppp
->pass_filter
);
2764 ppp
->pass_filter
= NULL
;
2765 kfree(ppp
->active_filter
);
2766 ppp
->active_filter
= NULL
;
2767 #endif /* CONFIG_PPP_FILTER */
2769 kfree_skb(ppp
->xmit_pending
);
2771 free_netdev(ppp
->dev
);
2775 * Locate an existing ppp unit.
2776 * The caller should have locked the all_ppp_mutex.
2779 ppp_find_unit(struct ppp_net
*pn
, int unit
)
2781 return unit_find(&pn
->units_idr
, unit
);
2785 * Locate an existing ppp channel.
2786 * The caller should have locked the all_channels_lock.
2787 * First we look in the new_channels list, then in the
2788 * all_channels list. If found in the new_channels list,
2789 * we move it to the all_channels list. This is for speed
2790 * when we have a lot of channels in use.
2792 static struct channel
*
2793 ppp_find_channel(struct ppp_net
*pn
, int unit
)
2795 struct channel
*pch
;
2797 list_for_each_entry(pch
, &pn
->new_channels
, list
) {
2798 if (pch
->file
.index
== unit
) {
2799 list_move(&pch
->list
, &pn
->all_channels
);
2804 list_for_each_entry(pch
, &pn
->all_channels
, list
) {
2805 if (pch
->file
.index
== unit
)
2813 * Connect a PPP channel to a PPP interface unit.
2816 ppp_connect_channel(struct channel
*pch
, int unit
)
2823 pn
= ppp_pernet(pch
->chan_net
);
2825 mutex_lock(&pn
->all_ppp_mutex
);
2826 ppp
= ppp_find_unit(pn
, unit
);
2829 write_lock_bh(&pch
->upl
);
2835 if (pch
->file
.hdrlen
> ppp
->file
.hdrlen
)
2836 ppp
->file
.hdrlen
= pch
->file
.hdrlen
;
2837 hdrlen
= pch
->file
.hdrlen
+ 2; /* for protocol bytes */
2838 if (hdrlen
> ppp
->dev
->hard_header_len
)
2839 ppp
->dev
->hard_header_len
= hdrlen
;
2840 list_add_tail(&pch
->clist
, &ppp
->channels
);
2843 atomic_inc(&ppp
->file
.refcnt
);
2848 write_unlock_bh(&pch
->upl
);
2850 mutex_unlock(&pn
->all_ppp_mutex
);
2855 * Disconnect a channel from its ppp unit.
2858 ppp_disconnect_channel(struct channel
*pch
)
2863 write_lock_bh(&pch
->upl
);
2866 write_unlock_bh(&pch
->upl
);
2868 /* remove it from the ppp unit's list */
2870 list_del(&pch
->clist
);
2871 if (--ppp
->n_channels
== 0)
2872 wake_up_interruptible(&ppp
->file
.rwait
);
2874 if (atomic_dec_and_test(&ppp
->file
.refcnt
))
2875 ppp_destroy_interface(ppp
);
2882 * Free up the resources used by a ppp channel.
2884 static void ppp_destroy_channel(struct channel
*pch
)
2886 atomic_dec(&channel_count
);
2888 if (!pch
->file
.dead
) {
2889 /* "can't happen" */
2890 pr_err("ppp: destroying undead channel %p !\n", pch
);
2893 skb_queue_purge(&pch
->file
.xq
);
2894 skb_queue_purge(&pch
->file
.rq
);
2898 static void __exit
ppp_cleanup(void)
2900 /* should never happen */
2901 if (atomic_read(&ppp_unit_count
) || atomic_read(&channel_count
))
2902 pr_err("PPP: removing module but units remain!\n");
2903 unregister_chrdev(PPP_MAJOR
, "ppp");
2904 device_destroy(ppp_class
, MKDEV(PPP_MAJOR
, 0));
2905 class_destroy(ppp_class
);
2906 unregister_pernet_device(&ppp_net_ops
);
2910 * Units handling. Caller must protect concurrent access
2911 * by holding all_ppp_mutex
2914 static int __unit_alloc(struct idr
*p
, void *ptr
, int n
)
2919 if (!idr_pre_get(p
, GFP_KERNEL
)) {
2920 pr_err("PPP: No free memory for idr\n");
2924 err
= idr_get_new_above(p
, ptr
, n
, &unit
);
2934 /* associate pointer with specified number */
2935 static int unit_set(struct idr
*p
, void *ptr
, int n
)
2939 unit
= __unit_alloc(p
, ptr
, n
);
2942 else if (unit
!= n
) {
2943 idr_remove(p
, unit
);
2950 /* get new free unit number and associate pointer with it */
2951 static int unit_get(struct idr
*p
, void *ptr
)
2953 return __unit_alloc(p
, ptr
, 0);
2956 /* put unit number back to a pool */
2957 static void unit_put(struct idr
*p
, int n
)
2962 /* get pointer associated with the number */
2963 static void *unit_find(struct idr
*p
, int n
)
2965 return idr_find(p
, n
);
2968 /* Module/initialization stuff */
2970 module_init(ppp_init
);
2971 module_exit(ppp_cleanup
);
2973 EXPORT_SYMBOL(ppp_register_net_channel
);
2974 EXPORT_SYMBOL(ppp_register_channel
);
2975 EXPORT_SYMBOL(ppp_unregister_channel
);
2976 EXPORT_SYMBOL(ppp_channel_index
);
2977 EXPORT_SYMBOL(ppp_unit_number
);
2978 EXPORT_SYMBOL(ppp_dev_name
);
2979 EXPORT_SYMBOL(ppp_input
);
2980 EXPORT_SYMBOL(ppp_input_error
);
2981 EXPORT_SYMBOL(ppp_output_wakeup
);
2982 EXPORT_SYMBOL(ppp_register_compressor
);
2983 EXPORT_SYMBOL(ppp_unregister_compressor
);
2984 MODULE_LICENSE("GPL");
2985 MODULE_ALIAS_CHARDEV(PPP_MAJOR
, 0);
2986 MODULE_ALIAS("devname:ppp");