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/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 <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 */
73 * An instance of /dev/ppp can be associated with either a ppp
74 * interface unit or a ppp channel. In both cases, file->private_data
75 * points to one of these.
81 struct sk_buff_head xq
; /* pppd transmit queue */
82 struct sk_buff_head rq
; /* receive queue for pppd */
83 wait_queue_head_t rwait
; /* for poll on reading /dev/ppp */
84 atomic_t refcnt
; /* # refs (incl /dev/ppp attached) */
85 int hdrlen
; /* space to leave for headers */
86 int index
; /* interface unit / channel number */
87 int dead
; /* unit/channel has been shut down */
90 #define PF_TO_X(pf, X) container_of(pf, X, file)
92 #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp)
93 #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel)
96 * Data structure describing one ppp unit.
97 * A ppp unit corresponds to a ppp network interface device
98 * and represents a multilink bundle.
99 * It can have 0 or more ppp channels connected to it.
102 struct ppp_file file
; /* stuff for read/write/poll 0 */
103 struct file
*owner
; /* file that owns this unit 48 */
104 struct list_head channels
; /* list of attached channels 4c */
105 int n_channels
; /* how many channels are attached 54 */
106 spinlock_t rlock
; /* lock for receive side 58 */
107 spinlock_t wlock
; /* lock for transmit side 5c */
108 int mru
; /* max receive unit 60 */
109 unsigned int flags
; /* control bits 64 */
110 unsigned int xstate
; /* transmit state bits 68 */
111 unsigned int rstate
; /* receive state bits 6c */
112 int debug
; /* debug flags 70 */
113 struct slcompress
*vj
; /* state for VJ header compression */
114 enum NPmode npmode
[NUM_NP
]; /* what to do with each net proto 78 */
115 struct sk_buff
*xmit_pending
; /* a packet ready to go out 88 */
116 struct compressor
*xcomp
; /* transmit packet compressor 8c */
117 void *xc_state
; /* its internal state 90 */
118 struct compressor
*rcomp
; /* receive decompressor 94 */
119 void *rc_state
; /* its internal state 98 */
120 unsigned long last_xmit
; /* jiffies when last pkt sent 9c */
121 unsigned long last_recv
; /* jiffies when last pkt rcvd a0 */
122 struct net_device
*dev
; /* network interface device a4 */
123 int closing
; /* is device closing down? a8 */
124 #ifdef CONFIG_PPP_MULTILINK
125 int nxchan
; /* next channel to send something on */
126 u32 nxseq
; /* next sequence number to send */
127 int mrru
; /* MP: max reconst. receive unit */
128 u32 nextseq
; /* MP: seq no of next packet */
129 u32 minseq
; /* MP: min of most recent seqnos */
130 struct sk_buff_head mrq
; /* MP: receive reconstruction queue */
131 #endif /* CONFIG_PPP_MULTILINK */
132 #ifdef CONFIG_PPP_FILTER
133 struct sock_filter
*pass_filter
; /* filter for packets to pass */
134 struct sock_filter
*active_filter
;/* filter for pkts to reset idle */
135 unsigned pass_len
, active_len
;
136 #endif /* CONFIG_PPP_FILTER */
137 struct net
*ppp_net
; /* the net we belong to */
141 * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
142 * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP,
144 * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR.
145 * Bits in xstate: SC_COMP_RUN
147 #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \
148 |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \
149 |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP)
152 * Private data structure for each channel.
153 * This includes the data structure used for multilink.
156 struct ppp_file file
; /* stuff for read/write/poll */
157 struct list_head list
; /* link in all/new_channels list */
158 struct ppp_channel
*chan
; /* public channel data structure */
159 struct rw_semaphore chan_sem
; /* protects `chan' during chan ioctl */
160 spinlock_t downl
; /* protects `chan', file.xq dequeue */
161 struct ppp
*ppp
; /* ppp unit we're connected to */
162 struct net
*chan_net
; /* the net channel belongs to */
163 struct list_head clist
; /* link in list of channels per unit */
164 rwlock_t upl
; /* protects `ppp' */
165 #ifdef CONFIG_PPP_MULTILINK
166 u8 avail
; /* flag used in multilink stuff */
167 u8 had_frag
; /* >= 1 fragments have been sent */
168 u32 lastseq
; /* MP: last sequence # received */
169 int speed
; /* speed of the corresponding ppp channel*/
170 #endif /* CONFIG_PPP_MULTILINK */
174 * SMP locking issues:
175 * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels
176 * list and the ppp.n_channels field, you need to take both locks
177 * before you modify them.
178 * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
182 static DEFINE_MUTEX(ppp_mutex
);
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 __read_mostly
;
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
)
366 * This could (should?) be enforced by the permissions on /dev/ppp.
368 if (!capable(CAP_NET_ADMIN
))
373 static int ppp_release(struct inode
*unused
, struct file
*file
)
375 struct ppp_file
*pf
= file
->private_data
;
379 file
->private_data
= NULL
;
380 if (pf
->kind
== INTERFACE
) {
382 if (file
== ppp
->owner
)
383 ppp_shutdown_interface(ppp
);
385 if (atomic_dec_and_test(&pf
->refcnt
)) {
388 ppp_destroy_interface(PF_TO_PPP(pf
));
391 ppp_destroy_channel(PF_TO_CHANNEL(pf
));
399 static ssize_t
ppp_read(struct file
*file
, char __user
*buf
,
400 size_t count
, loff_t
*ppos
)
402 struct ppp_file
*pf
= file
->private_data
;
403 DECLARE_WAITQUEUE(wait
, current
);
405 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
)
452 if (skb_copy_datagram_iovec(skb
, 0, &iov
, skb
->len
))
462 static ssize_t
ppp_write(struct file
*file
, const char __user
*buf
,
463 size_t count
, loff_t
*ppos
)
465 struct ppp_file
*pf
= file
->private_data
;
472 skb
= alloc_skb(count
+ pf
->hdrlen
, GFP_KERNEL
);
475 skb_reserve(skb
, pf
->hdrlen
);
477 if (copy_from_user(skb_put(skb
, count
), buf
, count
)) {
482 skb_queue_tail(&pf
->xq
, skb
);
486 ppp_xmit_process(PF_TO_PPP(pf
));
489 ppp_channel_push(PF_TO_CHANNEL(pf
));
499 /* No kernel lock - fine */
500 static unsigned int ppp_poll(struct file
*file
, poll_table
*wait
)
502 struct ppp_file
*pf
= file
->private_data
;
507 poll_wait(file
, &pf
->rwait
, wait
);
508 mask
= POLLOUT
| POLLWRNORM
;
509 if (skb_peek(&pf
->rq
))
510 mask
|= POLLIN
| POLLRDNORM
;
513 else if (pf
->kind
== INTERFACE
) {
514 /* see comment in ppp_read */
515 struct ppp
*ppp
= PF_TO_PPP(pf
);
516 if (ppp
->n_channels
== 0 &&
517 (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0)
518 mask
|= POLLIN
| POLLRDNORM
;
524 #ifdef CONFIG_PPP_FILTER
525 static int get_filter(void __user
*arg
, struct sock_filter
**p
)
527 struct sock_fprog uprog
;
528 struct sock_filter
*code
= NULL
;
531 if (copy_from_user(&uprog
, arg
, sizeof(uprog
)))
539 len
= uprog
.len
* sizeof(struct sock_filter
);
540 code
= memdup_user(uprog
.filter
, len
);
542 return PTR_ERR(code
);
544 err
= sk_chk_filter(code
, uprog
.len
);
553 #endif /* CONFIG_PPP_FILTER */
555 static long ppp_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
557 struct ppp_file
*pf
= file
->private_data
;
559 int err
= -EFAULT
, val
, val2
, i
;
560 struct ppp_idle idle
;
563 struct slcompress
*vj
;
564 void __user
*argp
= (void __user
*)arg
;
565 int __user
*p
= argp
;
568 return ppp_unattached_ioctl(current
->nsproxy
->net_ns
,
571 if (cmd
== PPPIOCDETACH
) {
573 * We have to be careful here... if the file descriptor
574 * has been dup'd, we could have another process in the
575 * middle of a poll using the same file *, so we had
576 * better not free the interface data structures -
577 * instead we fail the ioctl. Even in this case, we
578 * shut down the interface if we are the owner of it.
579 * Actually, we should get rid of PPPIOCDETACH, userland
580 * (i.e. pppd) could achieve the same effect by closing
581 * this fd and reopening /dev/ppp.
584 mutex_lock(&ppp_mutex
);
585 if (pf
->kind
== INTERFACE
) {
587 if (file
== ppp
->owner
)
588 ppp_shutdown_interface(ppp
);
590 if (atomic_long_read(&file
->f_count
) <= 2) {
591 ppp_release(NULL
, file
);
594 printk(KERN_DEBUG
"PPPIOCDETACH file->f_count=%ld\n",
595 atomic_long_read(&file
->f_count
));
596 mutex_unlock(&ppp_mutex
);
600 if (pf
->kind
== CHANNEL
) {
602 struct ppp_channel
*chan
;
604 mutex_lock(&ppp_mutex
);
605 pch
= PF_TO_CHANNEL(pf
);
609 if (get_user(unit
, p
))
611 err
= ppp_connect_channel(pch
, unit
);
615 err
= ppp_disconnect_channel(pch
);
619 down_read(&pch
->chan_sem
);
622 if (chan
&& chan
->ops
->ioctl
)
623 err
= chan
->ops
->ioctl(chan
, cmd
, arg
);
624 up_read(&pch
->chan_sem
);
626 mutex_unlock(&ppp_mutex
);
630 if (pf
->kind
!= INTERFACE
) {
632 printk(KERN_ERR
"PPP: not interface or channel??\n");
636 mutex_lock(&ppp_mutex
);
640 if (get_user(val
, p
))
647 if (get_user(val
, p
))
650 cflags
= ppp
->flags
& ~val
;
651 ppp
->flags
= val
& SC_FLAG_BITS
;
653 if (cflags
& SC_CCP_OPEN
)
659 val
= ppp
->flags
| ppp
->xstate
| ppp
->rstate
;
660 if (put_user(val
, p
))
665 case PPPIOCSCOMPRESS
:
666 err
= ppp_set_compress(ppp
, arg
);
670 if (put_user(ppp
->file
.index
, p
))
676 if (get_user(val
, p
))
683 if (put_user(ppp
->debug
, p
))
689 idle
.xmit_idle
= (jiffies
- ppp
->last_xmit
) / HZ
;
690 idle
.recv_idle
= (jiffies
- ppp
->last_recv
) / HZ
;
691 if (copy_to_user(argp
, &idle
, sizeof(idle
)))
697 if (get_user(val
, p
))
700 if ((val
>> 16) != 0) {
704 vj
= slhc_init(val2
+1, val
+1);
706 printk(KERN_ERR
"PPP: no memory (VJ compressor)\n");
720 if (copy_from_user(&npi
, argp
, sizeof(npi
)))
722 err
= proto_to_npindex(npi
.protocol
);
726 if (cmd
== PPPIOCGNPMODE
) {
728 npi
.mode
= ppp
->npmode
[i
];
729 if (copy_to_user(argp
, &npi
, sizeof(npi
)))
732 ppp
->npmode
[i
] = npi
.mode
;
733 /* we may be able to transmit more packets now (??) */
734 netif_wake_queue(ppp
->dev
);
739 #ifdef CONFIG_PPP_FILTER
742 struct sock_filter
*code
;
743 err
= get_filter(argp
, &code
);
746 kfree(ppp
->pass_filter
);
747 ppp
->pass_filter
= code
;
756 struct sock_filter
*code
;
757 err
= get_filter(argp
, &code
);
760 kfree(ppp
->active_filter
);
761 ppp
->active_filter
= code
;
762 ppp
->active_len
= err
;
768 #endif /* CONFIG_PPP_FILTER */
770 #ifdef CONFIG_PPP_MULTILINK
772 if (get_user(val
, p
))
776 ppp_recv_unlock(ppp
);
779 #endif /* CONFIG_PPP_MULTILINK */
784 mutex_unlock(&ppp_mutex
);
788 static int ppp_unattached_ioctl(struct net
*net
, struct ppp_file
*pf
,
789 struct file
*file
, unsigned int cmd
, unsigned long arg
)
791 int unit
, err
= -EFAULT
;
793 struct channel
*chan
;
795 int __user
*p
= (int __user
*)arg
;
797 mutex_lock(&ppp_mutex
);
800 /* Create a new ppp unit */
801 if (get_user(unit
, p
))
803 ppp
= ppp_create_interface(net
, unit
, &err
);
806 file
->private_data
= &ppp
->file
;
809 if (put_user(ppp
->file
.index
, p
))
815 /* Attach to an existing ppp unit */
816 if (get_user(unit
, p
))
819 pn
= ppp_pernet(net
);
820 mutex_lock(&pn
->all_ppp_mutex
);
821 ppp
= ppp_find_unit(pn
, unit
);
823 atomic_inc(&ppp
->file
.refcnt
);
824 file
->private_data
= &ppp
->file
;
827 mutex_unlock(&pn
->all_ppp_mutex
);
831 if (get_user(unit
, p
))
834 pn
= ppp_pernet(net
);
835 spin_lock_bh(&pn
->all_channels_lock
);
836 chan
= ppp_find_channel(pn
, unit
);
838 atomic_inc(&chan
->file
.refcnt
);
839 file
->private_data
= &chan
->file
;
842 spin_unlock_bh(&pn
->all_channels_lock
);
848 mutex_unlock(&ppp_mutex
);
852 static const struct file_operations ppp_device_fops
= {
853 .owner
= THIS_MODULE
,
857 .unlocked_ioctl
= ppp_ioctl
,
859 .release
= ppp_release
862 static __net_init
int ppp_init_net(struct net
*net
)
864 struct ppp_net
*pn
= net_generic(net
, ppp_net_id
);
866 idr_init(&pn
->units_idr
);
867 mutex_init(&pn
->all_ppp_mutex
);
869 INIT_LIST_HEAD(&pn
->all_channels
);
870 INIT_LIST_HEAD(&pn
->new_channels
);
872 spin_lock_init(&pn
->all_channels_lock
);
877 static __net_exit
void ppp_exit_net(struct net
*net
)
879 struct ppp_net
*pn
= net_generic(net
, ppp_net_id
);
881 idr_destroy(&pn
->units_idr
);
884 static struct pernet_operations ppp_net_ops
= {
885 .init
= ppp_init_net
,
886 .exit
= ppp_exit_net
,
888 .size
= sizeof(struct ppp_net
),
891 #define PPP_MAJOR 108
893 /* Called at boot time if ppp is compiled into the kernel,
894 or at module load time (from init_module) if compiled as a module. */
895 static int __init
ppp_init(void)
899 printk(KERN_INFO
"PPP generic driver version " PPP_VERSION
"\n");
901 err
= register_pernet_device(&ppp_net_ops
);
903 printk(KERN_ERR
"failed to register PPP pernet device (%d)\n", err
);
907 err
= register_chrdev(PPP_MAJOR
, "ppp", &ppp_device_fops
);
909 printk(KERN_ERR
"failed to register PPP device (%d)\n", err
);
913 ppp_class
= class_create(THIS_MODULE
, "ppp");
914 if (IS_ERR(ppp_class
)) {
915 err
= PTR_ERR(ppp_class
);
919 /* not a big deal if we fail here :-) */
920 device_create(ppp_class
, NULL
, MKDEV(PPP_MAJOR
, 0), NULL
, "ppp");
925 unregister_chrdev(PPP_MAJOR
, "ppp");
927 unregister_pernet_device(&ppp_net_ops
);
933 * Network interface unit routines.
936 ppp_start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
938 struct ppp
*ppp
= netdev_priv(dev
);
942 npi
= ethertype_to_npindex(ntohs(skb
->protocol
));
946 /* Drop, accept or reject the packet */
947 switch (ppp
->npmode
[npi
]) {
951 /* it would be nice to have a way to tell the network
952 system to queue this one up for later. */
959 /* Put the 2-byte PPP protocol number on the front,
960 making sure there is room for the address and control fields. */
961 if (skb_cow_head(skb
, PPP_HDRLEN
))
964 pp
= skb_push(skb
, 2);
965 proto
= npindex_to_proto
[npi
];
969 netif_stop_queue(dev
);
970 skb_queue_tail(&ppp
->file
.xq
, skb
);
971 ppp_xmit_process(ppp
);
976 ++dev
->stats
.tx_dropped
;
981 ppp_net_ioctl(struct net_device
*dev
, struct ifreq
*ifr
, int cmd
)
983 struct ppp
*ppp
= netdev_priv(dev
);
985 void __user
*addr
= (void __user
*) ifr
->ifr_ifru
.ifru_data
;
986 struct ppp_stats stats
;
987 struct ppp_comp_stats cstats
;
992 ppp_get_stats(ppp
, &stats
);
993 if (copy_to_user(addr
, &stats
, sizeof(stats
)))
999 memset(&cstats
, 0, sizeof(cstats
));
1001 ppp
->xcomp
->comp_stat(ppp
->xc_state
, &cstats
.c
);
1003 ppp
->rcomp
->decomp_stat(ppp
->rc_state
, &cstats
.d
);
1004 if (copy_to_user(addr
, &cstats
, sizeof(cstats
)))
1011 if (copy_to_user(addr
, vers
, strlen(vers
) + 1))
1023 static const struct net_device_ops ppp_netdev_ops
= {
1024 .ndo_start_xmit
= ppp_start_xmit
,
1025 .ndo_do_ioctl
= ppp_net_ioctl
,
1028 static void ppp_setup(struct net_device
*dev
)
1030 dev
->netdev_ops
= &ppp_netdev_ops
;
1031 dev
->hard_header_len
= PPP_HDRLEN
;
1034 dev
->tx_queue_len
= 3;
1035 dev
->type
= ARPHRD_PPP
;
1036 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
1037 dev
->features
|= NETIF_F_NETNS_LOCAL
;
1038 dev
->priv_flags
&= ~IFF_XMIT_DST_RELEASE
;
1042 * Transmit-side routines.
1046 * Called to do any work queued up on the transmit side
1047 * that can now be done.
1050 ppp_xmit_process(struct ppp
*ppp
)
1052 struct sk_buff
*skb
;
1055 if (!ppp
->closing
) {
1057 while (!ppp
->xmit_pending
&&
1058 (skb
= skb_dequeue(&ppp
->file
.xq
)))
1059 ppp_send_frame(ppp
, skb
);
1060 /* If there's no work left to do, tell the core net
1061 code that we can accept some more. */
1062 if (!ppp
->xmit_pending
&& !skb_peek(&ppp
->file
.xq
))
1063 netif_wake_queue(ppp
->dev
);
1065 ppp_xmit_unlock(ppp
);
1068 static inline struct sk_buff
*
1069 pad_compress_skb(struct ppp
*ppp
, struct sk_buff
*skb
)
1071 struct sk_buff
*new_skb
;
1073 int new_skb_size
= ppp
->dev
->mtu
+
1074 ppp
->xcomp
->comp_extra
+ ppp
->dev
->hard_header_len
;
1075 int compressor_skb_size
= ppp
->dev
->mtu
+
1076 ppp
->xcomp
->comp_extra
+ PPP_HDRLEN
;
1077 new_skb
= alloc_skb(new_skb_size
, GFP_ATOMIC
);
1079 if (net_ratelimit())
1080 printk(KERN_ERR
"PPP: no memory (comp pkt)\n");
1083 if (ppp
->dev
->hard_header_len
> PPP_HDRLEN
)
1084 skb_reserve(new_skb
,
1085 ppp
->dev
->hard_header_len
- PPP_HDRLEN
);
1087 /* compressor still expects A/C bytes in hdr */
1088 len
= ppp
->xcomp
->compress(ppp
->xc_state
, skb
->data
- 2,
1089 new_skb
->data
, skb
->len
+ 2,
1090 compressor_skb_size
);
1091 if (len
> 0 && (ppp
->flags
& SC_CCP_UP
)) {
1095 skb_pull(skb
, 2); /* pull off A/C bytes */
1096 } else if (len
== 0) {
1097 /* didn't compress, or CCP not up yet */
1103 * MPPE requires that we do not send unencrypted
1104 * frames. The compressor will return -1 if we
1105 * should drop the frame. We cannot simply test
1106 * the compress_proto because MPPE and MPPC share
1109 if (net_ratelimit())
1110 printk(KERN_ERR
"ppp: compressor dropped pkt\n");
1119 * Compress and send a frame.
1120 * The caller should have locked the xmit path,
1121 * and xmit_pending should be 0.
1124 ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1126 int proto
= PPP_PROTO(skb
);
1127 struct sk_buff
*new_skb
;
1131 if (proto
< 0x8000) {
1132 #ifdef CONFIG_PPP_FILTER
1133 /* check if we should pass this packet */
1134 /* the filter instructions are constructed assuming
1135 a four-byte PPP header on each packet */
1136 *skb_push(skb
, 2) = 1;
1137 if (ppp
->pass_filter
&&
1138 sk_run_filter(skb
, ppp
->pass_filter
,
1139 ppp
->pass_len
) == 0) {
1141 printk(KERN_DEBUG
"PPP: outbound frame not passed\n");
1145 /* if this packet passes the active filter, record the time */
1146 if (!(ppp
->active_filter
&&
1147 sk_run_filter(skb
, ppp
->active_filter
,
1148 ppp
->active_len
) == 0))
1149 ppp
->last_xmit
= jiffies
;
1152 /* for data packets, record the time */
1153 ppp
->last_xmit
= jiffies
;
1154 #endif /* CONFIG_PPP_FILTER */
1157 ++ppp
->dev
->stats
.tx_packets
;
1158 ppp
->dev
->stats
.tx_bytes
+= skb
->len
- 2;
1162 if (!ppp
->vj
|| (ppp
->flags
& SC_COMP_TCP
) == 0)
1164 /* try to do VJ TCP header compression */
1165 new_skb
= alloc_skb(skb
->len
+ ppp
->dev
->hard_header_len
- 2,
1168 printk(KERN_ERR
"PPP: no memory (VJ comp pkt)\n");
1171 skb_reserve(new_skb
, ppp
->dev
->hard_header_len
- 2);
1173 len
= slhc_compress(ppp
->vj
, cp
, skb
->len
- 2,
1174 new_skb
->data
+ 2, &cp
,
1175 !(ppp
->flags
& SC_NO_TCP_CCID
));
1176 if (cp
== skb
->data
+ 2) {
1177 /* didn't compress */
1180 if (cp
[0] & SL_TYPE_COMPRESSED_TCP
) {
1181 proto
= PPP_VJC_COMP
;
1182 cp
[0] &= ~SL_TYPE_COMPRESSED_TCP
;
1184 proto
= PPP_VJC_UNCOMP
;
1185 cp
[0] = skb
->data
[2];
1189 cp
= skb_put(skb
, len
+ 2);
1196 /* peek at outbound CCP frames */
1197 ppp_ccp_peek(ppp
, skb
, 0);
1201 /* try to do packet compression */
1202 if ((ppp
->xstate
& SC_COMP_RUN
) && ppp
->xc_state
&&
1203 proto
!= PPP_LCP
&& proto
!= PPP_CCP
) {
1204 if (!(ppp
->flags
& SC_CCP_UP
) && (ppp
->flags
& SC_MUST_COMP
)) {
1205 if (net_ratelimit())
1206 printk(KERN_ERR
"ppp: compression required but down - pkt dropped.\n");
1209 skb
= pad_compress_skb(ppp
, skb
);
1215 * If we are waiting for traffic (demand dialling),
1216 * queue it up for pppd to receive.
1218 if (ppp
->flags
& SC_LOOP_TRAFFIC
) {
1219 if (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
)
1221 skb_queue_tail(&ppp
->file
.rq
, skb
);
1222 wake_up_interruptible(&ppp
->file
.rwait
);
1226 ppp
->xmit_pending
= skb
;
1232 ++ppp
->dev
->stats
.tx_errors
;
1236 * Try to send the frame in xmit_pending.
1237 * The caller should have the xmit path locked.
1240 ppp_push(struct ppp
*ppp
)
1242 struct list_head
*list
;
1243 struct channel
*pch
;
1244 struct sk_buff
*skb
= ppp
->xmit_pending
;
1249 list
= &ppp
->channels
;
1250 if (list_empty(list
)) {
1251 /* nowhere to send the packet, just drop it */
1252 ppp
->xmit_pending
= NULL
;
1257 if ((ppp
->flags
& SC_MULTILINK
) == 0) {
1258 /* not doing multilink: send it down the first channel */
1260 pch
= list_entry(list
, struct channel
, clist
);
1262 spin_lock_bh(&pch
->downl
);
1264 if (pch
->chan
->ops
->start_xmit(pch
->chan
, skb
))
1265 ppp
->xmit_pending
= NULL
;
1267 /* channel got unregistered */
1269 ppp
->xmit_pending
= NULL
;
1271 spin_unlock_bh(&pch
->downl
);
1275 #ifdef CONFIG_PPP_MULTILINK
1276 /* Multilink: fragment the packet over as many links
1277 as can take the packet at the moment. */
1278 if (!ppp_mp_explode(ppp
, skb
))
1280 #endif /* CONFIG_PPP_MULTILINK */
1282 ppp
->xmit_pending
= NULL
;
1286 #ifdef CONFIG_PPP_MULTILINK
1288 * Divide a packet to be transmitted into fragments and
1289 * send them out the individual links.
1291 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
)
1294 int i
, bits
, hdrlen
, mtu
;
1296 int navail
, nfree
, nzero
;
1300 unsigned char *p
, *q
;
1301 struct list_head
*list
;
1302 struct channel
*pch
;
1303 struct sk_buff
*frag
;
1304 struct ppp_channel
*chan
;
1306 totspeed
= 0; /*total bitrate of the bundle*/
1307 nfree
= 0; /* # channels which have no packet already queued */
1308 navail
= 0; /* total # of usable channels (not deregistered) */
1309 nzero
= 0; /* number of channels with zero speed associated*/
1310 totfree
= 0; /*total # of channels available and
1311 *having no queued packets before
1312 *starting the fragmentation*/
1314 hdrlen
= (ppp
->flags
& SC_MP_XSHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1316 list_for_each_entry(pch
, &ppp
->channels
, clist
) {
1320 pch
->speed
= pch
->chan
->speed
;
1325 if (skb_queue_empty(&pch
->file
.xq
) ||
1327 if (pch
->speed
== 0)
1330 totspeed
+= pch
->speed
;
1336 if (!pch
->had_frag
&& i
< ppp
->nxchan
)
1342 * Don't start sending this packet unless at least half of
1343 * the channels are free. This gives much better TCP
1344 * performance if we have a lot of channels.
1346 if (nfree
== 0 || nfree
< navail
/ 2)
1347 return 0; /* can't take now, leave it in xmit_pending */
1349 /* Do protocol field compression (XXX this should be optional) */
1358 nbigger
= len
% nfree
;
1360 /* skip to the channel after the one we last used
1361 and start at that one */
1362 list
= &ppp
->channels
;
1363 for (i
= 0; i
< ppp
->nxchan
; ++i
) {
1365 if (list
== &ppp
->channels
) {
1371 /* create a fragment for each channel */
1375 if (list
== &ppp
->channels
) {
1379 pch
= list_entry(list
, struct channel
, clist
);
1385 * Skip this channel if it has a fragment pending already and
1386 * we haven't given a fragment to all of the free channels.
1388 if (pch
->avail
== 1) {
1395 /* check the channel's mtu and whether it is still attached. */
1396 spin_lock_bh(&pch
->downl
);
1397 if (pch
->chan
== NULL
) {
1398 /* can't use this channel, it's being deregistered */
1399 if (pch
->speed
== 0)
1402 totspeed
-= pch
->speed
;
1404 spin_unlock_bh(&pch
->downl
);
1415 *if the channel speed is not set divide
1416 *the packet evenly among the free channels;
1417 *otherwise divide it according to the speed
1418 *of the channel we are going to transmit on
1422 if (pch
->speed
== 0) {
1429 flen
= (((totfree
- nzero
)*(totlen
+ hdrlen
*totfree
)) /
1430 ((totspeed
*totfree
)/pch
->speed
)) - hdrlen
;
1432 flen
+= ((totfree
- nzero
)*pch
->speed
)/totspeed
;
1433 nbigger
-= ((totfree
- nzero
)*pch
->speed
)/
1441 *check if we are on the last channel or
1442 *we exceded the lenght of the data to
1445 if ((nfree
<= 0) || (flen
> len
))
1448 *it is not worth to tx on slow channels:
1449 *in that case from the resulting flen according to the
1450 *above formula will be equal or less than zero.
1451 *Skip the channel in this case
1455 spin_unlock_bh(&pch
->downl
);
1459 mtu
= pch
->chan
->mtu
- hdrlen
;
1466 frag
= alloc_skb(flen
+ hdrlen
+ (flen
== 0), GFP_ATOMIC
);
1469 q
= skb_put(frag
, flen
+ hdrlen
);
1471 /* make the MP header */
1474 if (ppp
->flags
& SC_MP_XSHORTSEQ
) {
1475 q
[2] = bits
+ ((ppp
->nxseq
>> 8) & 0xf);
1479 q
[3] = ppp
->nxseq
>> 16;
1480 q
[4] = ppp
->nxseq
>> 8;
1484 memcpy(q
+ hdrlen
, p
, flen
);
1486 /* try to send it down the channel */
1488 if (!skb_queue_empty(&pch
->file
.xq
) ||
1489 !chan
->ops
->start_xmit(chan
, frag
))
1490 skb_queue_tail(&pch
->file
.xq
, frag
);
1496 spin_unlock_bh(&pch
->downl
);
1503 spin_unlock_bh(&pch
->downl
);
1505 printk(KERN_ERR
"PPP: no memory (fragment)\n");
1506 ++ppp
->dev
->stats
.tx_errors
;
1508 return 1; /* abandon the frame */
1510 #endif /* CONFIG_PPP_MULTILINK */
1513 * Try to send data out on a channel.
1516 ppp_channel_push(struct channel
*pch
)
1518 struct sk_buff
*skb
;
1521 spin_lock_bh(&pch
->downl
);
1523 while (!skb_queue_empty(&pch
->file
.xq
)) {
1524 skb
= skb_dequeue(&pch
->file
.xq
);
1525 if (!pch
->chan
->ops
->start_xmit(pch
->chan
, skb
)) {
1526 /* put the packet back and try again later */
1527 skb_queue_head(&pch
->file
.xq
, skb
);
1532 /* channel got deregistered */
1533 skb_queue_purge(&pch
->file
.xq
);
1535 spin_unlock_bh(&pch
->downl
);
1536 /* see if there is anything from the attached unit to be sent */
1537 if (skb_queue_empty(&pch
->file
.xq
)) {
1538 read_lock_bh(&pch
->upl
);
1541 ppp_xmit_process(ppp
);
1542 read_unlock_bh(&pch
->upl
);
1547 * Receive-side routines.
1550 struct ppp_mp_skb_parm
{
1554 #define PPP_MP_CB(skb) ((struct ppp_mp_skb_parm *)((skb)->cb))
1557 ppp_do_recv(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1561 ppp_receive_frame(ppp
, skb
, pch
);
1564 ppp_recv_unlock(ppp
);
1568 ppp_input(struct ppp_channel
*chan
, struct sk_buff
*skb
)
1570 struct channel
*pch
= chan
->ppp
;
1578 read_lock_bh(&pch
->upl
);
1579 if (!pskb_may_pull(skb
, 2)) {
1582 ++pch
->ppp
->dev
->stats
.rx_length_errors
;
1583 ppp_receive_error(pch
->ppp
);
1588 proto
= PPP_PROTO(skb
);
1589 if (!pch
->ppp
|| proto
>= 0xc000 || proto
== PPP_CCPFRAG
) {
1590 /* put it on the channel queue */
1591 skb_queue_tail(&pch
->file
.rq
, skb
);
1592 /* drop old frames if queue too long */
1593 while (pch
->file
.rq
.qlen
> PPP_MAX_RQLEN
&&
1594 (skb
= skb_dequeue(&pch
->file
.rq
)))
1596 wake_up_interruptible(&pch
->file
.rwait
);
1598 ppp_do_recv(pch
->ppp
, skb
, pch
);
1602 read_unlock_bh(&pch
->upl
);
1605 /* Put a 0-length skb in the receive queue as an error indication */
1607 ppp_input_error(struct ppp_channel
*chan
, int code
)
1609 struct channel
*pch
= chan
->ppp
;
1610 struct sk_buff
*skb
;
1615 read_lock_bh(&pch
->upl
);
1617 skb
= alloc_skb(0, GFP_ATOMIC
);
1619 skb
->len
= 0; /* probably unnecessary */
1621 ppp_do_recv(pch
->ppp
, skb
, pch
);
1624 read_unlock_bh(&pch
->upl
);
1628 * We come in here to process a received frame.
1629 * The receive side of the ppp unit is locked.
1632 ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1634 /* note: a 0-length skb is used as an error indication */
1636 #ifdef CONFIG_PPP_MULTILINK
1637 /* XXX do channel-level decompression here */
1638 if (PPP_PROTO(skb
) == PPP_MP
)
1639 ppp_receive_mp_frame(ppp
, skb
, pch
);
1641 #endif /* CONFIG_PPP_MULTILINK */
1642 ppp_receive_nonmp_frame(ppp
, skb
);
1645 ppp_receive_error(ppp
);
1650 ppp_receive_error(struct ppp
*ppp
)
1652 ++ppp
->dev
->stats
.rx_errors
;
1658 ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1661 int proto
, len
, npi
;
1664 * Decompress the frame, if compressed.
1665 * Note that some decompressors need to see uncompressed frames
1666 * that come in as well as compressed frames.
1668 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
) &&
1669 (ppp
->rstate
& (SC_DC_FERROR
| SC_DC_ERROR
)) == 0)
1670 skb
= ppp_decompress_frame(ppp
, skb
);
1672 if (ppp
->flags
& SC_MUST_COMP
&& ppp
->rstate
& SC_DC_FERROR
)
1675 proto
= PPP_PROTO(skb
);
1678 /* decompress VJ compressed packets */
1679 if (!ppp
->vj
|| (ppp
->flags
& SC_REJ_COMP_TCP
))
1682 if (skb_tailroom(skb
) < 124 || skb_cloned(skb
)) {
1683 /* copy to a new sk_buff with more tailroom */
1684 ns
= dev_alloc_skb(skb
->len
+ 128);
1686 printk(KERN_ERR
"PPP: no memory (VJ decomp)\n");
1690 skb_copy_bits(skb
, 0, skb_put(ns
, skb
->len
), skb
->len
);
1695 skb
->ip_summed
= CHECKSUM_NONE
;
1697 len
= slhc_uncompress(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2);
1699 printk(KERN_DEBUG
"PPP: VJ decompression error\n");
1704 skb_put(skb
, len
- skb
->len
);
1705 else if (len
< skb
->len
)
1710 case PPP_VJC_UNCOMP
:
1711 if (!ppp
->vj
|| (ppp
->flags
& SC_REJ_COMP_TCP
))
1714 /* Until we fix the decompressor need to make sure
1715 * data portion is linear.
1717 if (!pskb_may_pull(skb
, skb
->len
))
1720 if (slhc_remember(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2) <= 0) {
1721 printk(KERN_ERR
"PPP: VJ uncompressed error\n");
1728 ppp_ccp_peek(ppp
, skb
, 1);
1732 ++ppp
->dev
->stats
.rx_packets
;
1733 ppp
->dev
->stats
.rx_bytes
+= skb
->len
- 2;
1735 npi
= proto_to_npindex(proto
);
1737 /* control or unknown frame - pass it to pppd */
1738 skb_queue_tail(&ppp
->file
.rq
, skb
);
1739 /* limit queue length by dropping old frames */
1740 while (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
&&
1741 (skb
= skb_dequeue(&ppp
->file
.rq
)))
1743 /* wake up any process polling or blocking on read */
1744 wake_up_interruptible(&ppp
->file
.rwait
);
1747 /* network protocol frame - give it to the kernel */
1749 #ifdef CONFIG_PPP_FILTER
1750 /* check if the packet passes the pass and active filters */
1751 /* the filter instructions are constructed assuming
1752 a four-byte PPP header on each packet */
1753 if (ppp
->pass_filter
|| ppp
->active_filter
) {
1754 if (skb_cloned(skb
) &&
1755 pskb_expand_head(skb
, 0, 0, GFP_ATOMIC
))
1758 *skb_push(skb
, 2) = 0;
1759 if (ppp
->pass_filter
&&
1760 sk_run_filter(skb
, ppp
->pass_filter
,
1761 ppp
->pass_len
) == 0) {
1763 printk(KERN_DEBUG
"PPP: inbound frame "
1768 if (!(ppp
->active_filter
&&
1769 sk_run_filter(skb
, ppp
->active_filter
,
1770 ppp
->active_len
) == 0))
1771 ppp
->last_recv
= jiffies
;
1774 #endif /* CONFIG_PPP_FILTER */
1775 ppp
->last_recv
= jiffies
;
1777 if ((ppp
->dev
->flags
& IFF_UP
) == 0 ||
1778 ppp
->npmode
[npi
] != NPMODE_PASS
) {
1781 /* chop off protocol */
1782 skb_pull_rcsum(skb
, 2);
1783 skb
->dev
= ppp
->dev
;
1784 skb
->protocol
= htons(npindex_to_ethertype
[npi
]);
1785 skb_reset_mac_header(skb
);
1793 ppp_receive_error(ppp
);
1796 static struct sk_buff
*
1797 ppp_decompress_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1799 int proto
= PPP_PROTO(skb
);
1803 /* Until we fix all the decompressor's need to make sure
1804 * data portion is linear.
1806 if (!pskb_may_pull(skb
, skb
->len
))
1809 if (proto
== PPP_COMP
) {
1812 switch(ppp
->rcomp
->compress_proto
) {
1814 obuff_size
= ppp
->mru
+ PPP_HDRLEN
+ 1;
1817 obuff_size
= ppp
->mru
+ PPP_HDRLEN
;
1821 ns
= dev_alloc_skb(obuff_size
);
1823 printk(KERN_ERR
"ppp_decompress_frame: no memory\n");
1826 /* the decompressor still expects the A/C bytes in the hdr */
1827 len
= ppp
->rcomp
->decompress(ppp
->rc_state
, skb
->data
- 2,
1828 skb
->len
+ 2, ns
->data
, obuff_size
);
1830 /* Pass the compressed frame to pppd as an
1831 error indication. */
1832 if (len
== DECOMP_FATALERROR
)
1833 ppp
->rstate
|= SC_DC_FERROR
;
1841 skb_pull(skb
, 2); /* pull off the A/C bytes */
1844 /* Uncompressed frame - pass to decompressor so it
1845 can update its dictionary if necessary. */
1846 if (ppp
->rcomp
->incomp
)
1847 ppp
->rcomp
->incomp(ppp
->rc_state
, skb
->data
- 2,
1854 ppp
->rstate
|= SC_DC_ERROR
;
1855 ppp_receive_error(ppp
);
1859 #ifdef CONFIG_PPP_MULTILINK
1861 * Receive a multilink frame.
1862 * We put it on the reconstruction queue and then pull off
1863 * as many completed frames as we can.
1866 ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1870 int mphdrlen
= (ppp
->flags
& SC_MP_SHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1872 if (!pskb_may_pull(skb
, mphdrlen
+ 1) || ppp
->mrru
== 0)
1873 goto err
; /* no good, throw it away */
1875 /* Decode sequence number and begin/end bits */
1876 if (ppp
->flags
& SC_MP_SHORTSEQ
) {
1877 seq
= ((skb
->data
[2] & 0x0f) << 8) | skb
->data
[3];
1880 seq
= (skb
->data
[3] << 16) | (skb
->data
[4] << 8)| skb
->data
[5];
1883 PPP_MP_CB(skb
)->BEbits
= skb
->data
[2];
1884 skb_pull(skb
, mphdrlen
); /* pull off PPP and MP headers */
1887 * Do protocol ID decompression on the first fragment of each packet.
1889 if ((PPP_MP_CB(skb
)->BEbits
& B
) && (skb
->data
[0] & 1))
1890 *skb_push(skb
, 1) = 0;
1893 * Expand sequence number to 32 bits, making it as close
1894 * as possible to ppp->minseq.
1896 seq
|= ppp
->minseq
& ~mask
;
1897 if ((int)(ppp
->minseq
- seq
) > (int)(mask
>> 1))
1899 else if ((int)(seq
- ppp
->minseq
) > (int)(mask
>> 1))
1900 seq
-= mask
+ 1; /* should never happen */
1901 PPP_MP_CB(skb
)->sequence
= seq
;
1905 * If this packet comes before the next one we were expecting,
1908 if (seq_before(seq
, ppp
->nextseq
)) {
1910 ++ppp
->dev
->stats
.rx_dropped
;
1911 ppp_receive_error(ppp
);
1916 * Reevaluate minseq, the minimum over all channels of the
1917 * last sequence number received on each channel. Because of
1918 * the increasing sequence number rule, we know that any fragment
1919 * before `minseq' which hasn't arrived is never going to arrive.
1920 * The list of channels can't change because we have the receive
1921 * side of the ppp unit locked.
1923 list_for_each_entry(ch
, &ppp
->channels
, clist
) {
1924 if (seq_before(ch
->lastseq
, seq
))
1927 if (seq_before(ppp
->minseq
, seq
))
1930 /* Put the fragment on the reconstruction queue */
1931 ppp_mp_insert(ppp
, skb
);
1933 /* If the queue is getting long, don't wait any longer for packets
1934 before the start of the queue. */
1935 if (skb_queue_len(&ppp
->mrq
) >= PPP_MP_MAX_QLEN
) {
1936 struct sk_buff
*mskb
= skb_peek(&ppp
->mrq
);
1937 if (seq_before(ppp
->minseq
, PPP_MP_CB(mskb
)->sequence
))
1938 ppp
->minseq
= PPP_MP_CB(mskb
)->sequence
;
1941 /* Pull completed packets off the queue and receive them. */
1942 while ((skb
= ppp_mp_reconstruct(ppp
))) {
1943 if (pskb_may_pull(skb
, 2))
1944 ppp_receive_nonmp_frame(ppp
, skb
);
1946 ++ppp
->dev
->stats
.rx_length_errors
;
1948 ppp_receive_error(ppp
);
1956 ppp_receive_error(ppp
);
1960 * Insert a fragment on the MP reconstruction queue.
1961 * The queue is ordered by increasing sequence number.
1964 ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
)
1967 struct sk_buff_head
*list
= &ppp
->mrq
;
1968 u32 seq
= PPP_MP_CB(skb
)->sequence
;
1970 /* N.B. we don't need to lock the list lock because we have the
1971 ppp unit receive-side lock. */
1972 skb_queue_walk(list
, p
) {
1973 if (seq_before(seq
, PPP_MP_CB(p
)->sequence
))
1976 __skb_queue_before(list
, p
, skb
);
1980 * Reconstruct a packet from the MP fragment queue.
1981 * We go through increasing sequence numbers until we find a
1982 * complete packet, or we get to the sequence number for a fragment
1983 * which hasn't arrived but might still do so.
1985 static struct sk_buff
*
1986 ppp_mp_reconstruct(struct ppp
*ppp
)
1988 u32 seq
= ppp
->nextseq
;
1989 u32 minseq
= ppp
->minseq
;
1990 struct sk_buff_head
*list
= &ppp
->mrq
;
1991 struct sk_buff
*p
, *next
;
1992 struct sk_buff
*head
, *tail
;
1993 struct sk_buff
*skb
= NULL
;
1994 int lost
= 0, len
= 0;
1996 if (ppp
->mrru
== 0) /* do nothing until mrru is set */
2000 for (p
= head
; p
!= (struct sk_buff
*) list
; p
= next
) {
2002 if (seq_before(PPP_MP_CB(p
)->sequence
, seq
)) {
2003 /* this can't happen, anyway ignore the skb */
2004 printk(KERN_ERR
"ppp_mp_reconstruct bad seq %u < %u\n",
2005 PPP_MP_CB(p
)->sequence
, seq
);
2009 if (PPP_MP_CB(p
)->sequence
!= seq
) {
2010 /* Fragment `seq' is missing. If it is after
2011 minseq, it might arrive later, so stop here. */
2012 if (seq_after(seq
, minseq
))
2014 /* Fragment `seq' is lost, keep going. */
2016 seq
= seq_before(minseq
, PPP_MP_CB(p
)->sequence
)?
2017 minseq
+ 1: PPP_MP_CB(p
)->sequence
;
2023 * At this point we know that all the fragments from
2024 * ppp->nextseq to seq are either present or lost.
2025 * Also, there are no complete packets in the queue
2026 * that have no missing fragments and end before this
2030 /* B bit set indicates this fragment starts a packet */
2031 if (PPP_MP_CB(p
)->BEbits
& B
) {
2039 /* Got a complete packet yet? */
2040 if (lost
== 0 && (PPP_MP_CB(p
)->BEbits
& E
) &&
2041 (PPP_MP_CB(head
)->BEbits
& B
)) {
2042 if (len
> ppp
->mrru
+ 2) {
2043 ++ppp
->dev
->stats
.rx_length_errors
;
2044 printk(KERN_DEBUG
"PPP: reconstructed packet"
2045 " is too long (%d)\n", len
);
2046 } else if (p
== head
) {
2047 /* fragment is complete packet - reuse skb */
2051 } else if ((skb
= dev_alloc_skb(len
)) == NULL
) {
2052 ++ppp
->dev
->stats
.rx_missed_errors
;
2053 printk(KERN_DEBUG
"PPP: no memory for "
2054 "reconstructed packet");
2059 ppp
->nextseq
= seq
+ 1;
2063 * If this is the ending fragment of a packet,
2064 * and we haven't found a complete valid packet yet,
2065 * we can discard up to and including this fragment.
2067 if (PPP_MP_CB(p
)->BEbits
& E
)
2073 /* If we have a complete packet, copy it all into one skb. */
2075 /* If we have discarded any fragments,
2076 signal a receive error. */
2077 if (PPP_MP_CB(head
)->sequence
!= ppp
->nextseq
) {
2079 printk(KERN_DEBUG
" missed pkts %u..%u\n",
2081 PPP_MP_CB(head
)->sequence
-1);
2082 ++ppp
->dev
->stats
.rx_dropped
;
2083 ppp_receive_error(ppp
);
2087 /* copy to a single skb */
2088 for (p
= head
; p
!= tail
->next
; p
= p
->next
)
2089 skb_copy_bits(p
, 0, skb_put(skb
, p
->len
), p
->len
);
2090 ppp
->nextseq
= PPP_MP_CB(tail
)->sequence
+ 1;
2094 /* Discard all the skbuffs that we have copied the data out of
2095 or that we can't use. */
2096 while ((p
= list
->next
) != head
) {
2097 __skb_unlink(p
, list
);
2103 #endif /* CONFIG_PPP_MULTILINK */
2106 * Channel interface.
2109 /* Create a new, unattached ppp channel. */
2110 int ppp_register_channel(struct ppp_channel
*chan
)
2112 return ppp_register_net_channel(current
->nsproxy
->net_ns
, chan
);
2115 /* Create a new, unattached ppp channel for specified net. */
2116 int ppp_register_net_channel(struct net
*net
, struct ppp_channel
*chan
)
2118 struct channel
*pch
;
2121 pch
= kzalloc(sizeof(struct channel
), GFP_KERNEL
);
2125 pn
= ppp_pernet(net
);
2129 pch
->chan_net
= net
;
2131 init_ppp_file(&pch
->file
, CHANNEL
);
2132 pch
->file
.hdrlen
= chan
->hdrlen
;
2133 #ifdef CONFIG_PPP_MULTILINK
2135 #endif /* CONFIG_PPP_MULTILINK */
2136 init_rwsem(&pch
->chan_sem
);
2137 spin_lock_init(&pch
->downl
);
2138 rwlock_init(&pch
->upl
);
2140 spin_lock_bh(&pn
->all_channels_lock
);
2141 pch
->file
.index
= ++pn
->last_channel_index
;
2142 list_add(&pch
->list
, &pn
->new_channels
);
2143 atomic_inc(&channel_count
);
2144 spin_unlock_bh(&pn
->all_channels_lock
);
2150 * Return the index of a channel.
2152 int ppp_channel_index(struct ppp_channel
*chan
)
2154 struct channel
*pch
= chan
->ppp
;
2157 return pch
->file
.index
;
2162 * Return the PPP unit number to which a channel is connected.
2164 int ppp_unit_number(struct ppp_channel
*chan
)
2166 struct channel
*pch
= chan
->ppp
;
2170 read_lock_bh(&pch
->upl
);
2172 unit
= pch
->ppp
->file
.index
;
2173 read_unlock_bh(&pch
->upl
);
2179 * Return the PPP device interface name of a channel.
2181 char *ppp_dev_name(struct ppp_channel
*chan
)
2183 struct channel
*pch
= chan
->ppp
;
2187 read_lock_bh(&pch
->upl
);
2188 if (pch
->ppp
&& pch
->ppp
->dev
)
2189 name
= pch
->ppp
->dev
->name
;
2190 read_unlock_bh(&pch
->upl
);
2197 * Disconnect a channel from the generic layer.
2198 * This must be called in process context.
2201 ppp_unregister_channel(struct ppp_channel
*chan
)
2203 struct channel
*pch
= chan
->ppp
;
2207 return; /* should never happen */
2212 * This ensures that we have returned from any calls into the
2213 * the channel's start_xmit or ioctl routine before we proceed.
2215 down_write(&pch
->chan_sem
);
2216 spin_lock_bh(&pch
->downl
);
2218 spin_unlock_bh(&pch
->downl
);
2219 up_write(&pch
->chan_sem
);
2220 ppp_disconnect_channel(pch
);
2222 pn
= ppp_pernet(pch
->chan_net
);
2223 spin_lock_bh(&pn
->all_channels_lock
);
2224 list_del(&pch
->list
);
2225 spin_unlock_bh(&pn
->all_channels_lock
);
2228 wake_up_interruptible(&pch
->file
.rwait
);
2229 if (atomic_dec_and_test(&pch
->file
.refcnt
))
2230 ppp_destroy_channel(pch
);
2234 * Callback from a channel when it can accept more to transmit.
2235 * This should be called at BH/softirq level, not interrupt level.
2238 ppp_output_wakeup(struct ppp_channel
*chan
)
2240 struct channel
*pch
= chan
->ppp
;
2244 ppp_channel_push(pch
);
2248 * Compression control.
2251 /* Process the PPPIOCSCOMPRESS ioctl. */
2253 ppp_set_compress(struct ppp
*ppp
, unsigned long arg
)
2256 struct compressor
*cp
, *ocomp
;
2257 struct ppp_option_data data
;
2258 void *state
, *ostate
;
2259 unsigned char ccp_option
[CCP_MAX_OPTION_LENGTH
];
2262 if (copy_from_user(&data
, (void __user
*) arg
, sizeof(data
)) ||
2263 (data
.length
<= CCP_MAX_OPTION_LENGTH
&&
2264 copy_from_user(ccp_option
, (void __user
*) data
.ptr
, data
.length
)))
2267 if (data
.length
> CCP_MAX_OPTION_LENGTH
||
2268 ccp_option
[1] < 2 || ccp_option
[1] > data
.length
)
2271 cp
= try_then_request_module(
2272 find_compressor(ccp_option
[0]),
2273 "ppp-compress-%d", ccp_option
[0]);
2278 if (data
.transmit
) {
2279 state
= cp
->comp_alloc(ccp_option
, data
.length
);
2282 ppp
->xstate
&= ~SC_COMP_RUN
;
2284 ostate
= ppp
->xc_state
;
2286 ppp
->xc_state
= state
;
2287 ppp_xmit_unlock(ppp
);
2289 ocomp
->comp_free(ostate
);
2290 module_put(ocomp
->owner
);
2294 module_put(cp
->owner
);
2297 state
= cp
->decomp_alloc(ccp_option
, data
.length
);
2300 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2302 ostate
= ppp
->rc_state
;
2304 ppp
->rc_state
= state
;
2305 ppp_recv_unlock(ppp
);
2307 ocomp
->decomp_free(ostate
);
2308 module_put(ocomp
->owner
);
2312 module_put(cp
->owner
);
2320 * Look at a CCP packet and update our state accordingly.
2321 * We assume the caller has the xmit or recv path locked.
2324 ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
)
2329 if (!pskb_may_pull(skb
, CCP_HDRLEN
+ 2))
2330 return; /* no header */
2333 switch (CCP_CODE(dp
)) {
2336 /* A ConfReq starts negotiation of compression
2337 * in one direction of transmission,
2338 * and hence brings it down...but which way?
2341 * A ConfReq indicates what the sender would like to receive
2344 /* He is proposing what I should send */
2345 ppp
->xstate
&= ~SC_COMP_RUN
;
2347 /* I am proposing to what he should send */
2348 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2355 * CCP is going down, both directions of transmission
2357 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2358 ppp
->xstate
&= ~SC_COMP_RUN
;
2362 if ((ppp
->flags
& (SC_CCP_OPEN
| SC_CCP_UP
)) != SC_CCP_OPEN
)
2364 len
= CCP_LENGTH(dp
);
2365 if (!pskb_may_pull(skb
, len
+ 2))
2366 return; /* too short */
2369 if (len
< CCP_OPT_MINLEN
|| len
< CCP_OPT_LENGTH(dp
))
2372 /* we will start receiving compressed packets */
2375 if (ppp
->rcomp
->decomp_init(ppp
->rc_state
, dp
, len
,
2376 ppp
->file
.index
, 0, ppp
->mru
, ppp
->debug
)) {
2377 ppp
->rstate
|= SC_DECOMP_RUN
;
2378 ppp
->rstate
&= ~(SC_DC_ERROR
| SC_DC_FERROR
);
2381 /* we will soon start sending compressed packets */
2384 if (ppp
->xcomp
->comp_init(ppp
->xc_state
, dp
, len
,
2385 ppp
->file
.index
, 0, ppp
->debug
))
2386 ppp
->xstate
|= SC_COMP_RUN
;
2391 /* reset the [de]compressor */
2392 if ((ppp
->flags
& SC_CCP_UP
) == 0)
2395 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
)) {
2396 ppp
->rcomp
->decomp_reset(ppp
->rc_state
);
2397 ppp
->rstate
&= ~SC_DC_ERROR
;
2400 if (ppp
->xc_state
&& (ppp
->xstate
& SC_COMP_RUN
))
2401 ppp
->xcomp
->comp_reset(ppp
->xc_state
);
2407 /* Free up compression resources. */
2409 ppp_ccp_closed(struct ppp
*ppp
)
2411 void *xstate
, *rstate
;
2412 struct compressor
*xcomp
, *rcomp
;
2415 ppp
->flags
&= ~(SC_CCP_OPEN
| SC_CCP_UP
);
2418 xstate
= ppp
->xc_state
;
2419 ppp
->xc_state
= NULL
;
2422 rstate
= ppp
->rc_state
;
2423 ppp
->rc_state
= NULL
;
2427 xcomp
->comp_free(xstate
);
2428 module_put(xcomp
->owner
);
2431 rcomp
->decomp_free(rstate
);
2432 module_put(rcomp
->owner
);
2436 /* List of compressors. */
2437 static LIST_HEAD(compressor_list
);
2438 static DEFINE_SPINLOCK(compressor_list_lock
);
2440 struct compressor_entry
{
2441 struct list_head list
;
2442 struct compressor
*comp
;
2445 static struct compressor_entry
*
2446 find_comp_entry(int proto
)
2448 struct compressor_entry
*ce
;
2450 list_for_each_entry(ce
, &compressor_list
, list
) {
2451 if (ce
->comp
->compress_proto
== proto
)
2457 /* Register a compressor */
2459 ppp_register_compressor(struct compressor
*cp
)
2461 struct compressor_entry
*ce
;
2463 spin_lock(&compressor_list_lock
);
2465 if (find_comp_entry(cp
->compress_proto
))
2468 ce
= kmalloc(sizeof(struct compressor_entry
), GFP_ATOMIC
);
2473 list_add(&ce
->list
, &compressor_list
);
2475 spin_unlock(&compressor_list_lock
);
2479 /* Unregister a compressor */
2481 ppp_unregister_compressor(struct compressor
*cp
)
2483 struct compressor_entry
*ce
;
2485 spin_lock(&compressor_list_lock
);
2486 ce
= find_comp_entry(cp
->compress_proto
);
2487 if (ce
&& ce
->comp
== cp
) {
2488 list_del(&ce
->list
);
2491 spin_unlock(&compressor_list_lock
);
2494 /* Find a compressor. */
2495 static struct compressor
*
2496 find_compressor(int type
)
2498 struct compressor_entry
*ce
;
2499 struct compressor
*cp
= NULL
;
2501 spin_lock(&compressor_list_lock
);
2502 ce
= find_comp_entry(type
);
2505 if (!try_module_get(cp
->owner
))
2508 spin_unlock(&compressor_list_lock
);
2513 * Miscelleneous stuff.
2517 ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
)
2519 struct slcompress
*vj
= ppp
->vj
;
2521 memset(st
, 0, sizeof(*st
));
2522 st
->p
.ppp_ipackets
= ppp
->dev
->stats
.rx_packets
;
2523 st
->p
.ppp_ierrors
= ppp
->dev
->stats
.rx_errors
;
2524 st
->p
.ppp_ibytes
= ppp
->dev
->stats
.rx_bytes
;
2525 st
->p
.ppp_opackets
= ppp
->dev
->stats
.tx_packets
;
2526 st
->p
.ppp_oerrors
= ppp
->dev
->stats
.tx_errors
;
2527 st
->p
.ppp_obytes
= ppp
->dev
->stats
.tx_bytes
;
2530 st
->vj
.vjs_packets
= vj
->sls_o_compressed
+ vj
->sls_o_uncompressed
;
2531 st
->vj
.vjs_compressed
= vj
->sls_o_compressed
;
2532 st
->vj
.vjs_searches
= vj
->sls_o_searches
;
2533 st
->vj
.vjs_misses
= vj
->sls_o_misses
;
2534 st
->vj
.vjs_errorin
= vj
->sls_i_error
;
2535 st
->vj
.vjs_tossed
= vj
->sls_i_tossed
;
2536 st
->vj
.vjs_uncompressedin
= vj
->sls_i_uncompressed
;
2537 st
->vj
.vjs_compressedin
= vj
->sls_i_compressed
;
2541 * Stuff for handling the lists of ppp units and channels
2542 * and for initialization.
2546 * Create a new ppp interface unit. Fails if it can't allocate memory
2547 * or if there is already a unit with the requested number.
2548 * unit == -1 means allocate a new number.
2551 ppp_create_interface(struct net
*net
, int unit
, int *retp
)
2555 struct net_device
*dev
= NULL
;
2559 dev
= alloc_netdev(sizeof(struct ppp
), "", ppp_setup
);
2563 pn
= ppp_pernet(net
);
2565 ppp
= netdev_priv(dev
);
2568 init_ppp_file(&ppp
->file
, INTERFACE
);
2569 ppp
->file
.hdrlen
= PPP_HDRLEN
- 2; /* don't count proto bytes */
2570 for (i
= 0; i
< NUM_NP
; ++i
)
2571 ppp
->npmode
[i
] = NPMODE_PASS
;
2572 INIT_LIST_HEAD(&ppp
->channels
);
2573 spin_lock_init(&ppp
->rlock
);
2574 spin_lock_init(&ppp
->wlock
);
2575 #ifdef CONFIG_PPP_MULTILINK
2577 skb_queue_head_init(&ppp
->mrq
);
2578 #endif /* CONFIG_PPP_MULTILINK */
2581 * drum roll: don't forget to set
2582 * the net device is belong to
2584 dev_net_set(dev
, net
);
2587 mutex_lock(&pn
->all_ppp_mutex
);
2590 unit
= unit_get(&pn
->units_idr
, ppp
);
2596 if (unit_find(&pn
->units_idr
, unit
))
2597 goto out2
; /* unit already exists */
2599 * if caller need a specified unit number
2600 * lets try to satisfy him, otherwise --
2601 * he should better ask us for new unit number
2603 * NOTE: yes I know that returning EEXIST it's not
2604 * fair but at least pppd will ask us to allocate
2605 * new unit in this case so user is happy :)
2607 unit
= unit_set(&pn
->units_idr
, ppp
, unit
);
2612 /* Initialize the new ppp unit */
2613 ppp
->file
.index
= unit
;
2614 sprintf(dev
->name
, "ppp%d", unit
);
2616 ret
= register_netdev(dev
);
2618 unit_put(&pn
->units_idr
, unit
);
2619 printk(KERN_ERR
"PPP: couldn't register device %s (%d)\n",
2626 atomic_inc(&ppp_unit_count
);
2627 mutex_unlock(&pn
->all_ppp_mutex
);
2633 mutex_unlock(&pn
->all_ppp_mutex
);
2641 * Initialize a ppp_file structure.
2644 init_ppp_file(struct ppp_file
*pf
, int kind
)
2647 skb_queue_head_init(&pf
->xq
);
2648 skb_queue_head_init(&pf
->rq
);
2649 atomic_set(&pf
->refcnt
, 1);
2650 init_waitqueue_head(&pf
->rwait
);
2654 * Take down a ppp interface unit - called when the owning file
2655 * (the one that created the unit) is closed or detached.
2657 static void ppp_shutdown_interface(struct ppp
*ppp
)
2661 pn
= ppp_pernet(ppp
->ppp_net
);
2662 mutex_lock(&pn
->all_ppp_mutex
);
2664 /* This will call dev_close() for us. */
2666 if (!ppp
->closing
) {
2669 unregister_netdev(ppp
->dev
);
2673 unit_put(&pn
->units_idr
, ppp
->file
.index
);
2676 wake_up_interruptible(&ppp
->file
.rwait
);
2678 mutex_unlock(&pn
->all_ppp_mutex
);
2682 * Free the memory used by a ppp unit. This is only called once
2683 * there are no channels connected to the unit and no file structs
2684 * that reference the unit.
2686 static void ppp_destroy_interface(struct ppp
*ppp
)
2688 atomic_dec(&ppp_unit_count
);
2690 if (!ppp
->file
.dead
|| ppp
->n_channels
) {
2691 /* "can't happen" */
2692 printk(KERN_ERR
"ppp: destroying ppp struct %p but dead=%d "
2693 "n_channels=%d !\n", ppp
, ppp
->file
.dead
,
2698 ppp_ccp_closed(ppp
);
2703 skb_queue_purge(&ppp
->file
.xq
);
2704 skb_queue_purge(&ppp
->file
.rq
);
2705 #ifdef CONFIG_PPP_MULTILINK
2706 skb_queue_purge(&ppp
->mrq
);
2707 #endif /* CONFIG_PPP_MULTILINK */
2708 #ifdef CONFIG_PPP_FILTER
2709 kfree(ppp
->pass_filter
);
2710 ppp
->pass_filter
= NULL
;
2711 kfree(ppp
->active_filter
);
2712 ppp
->active_filter
= NULL
;
2713 #endif /* CONFIG_PPP_FILTER */
2715 kfree_skb(ppp
->xmit_pending
);
2717 free_netdev(ppp
->dev
);
2721 * Locate an existing ppp unit.
2722 * The caller should have locked the all_ppp_mutex.
2725 ppp_find_unit(struct ppp_net
*pn
, int unit
)
2727 return unit_find(&pn
->units_idr
, unit
);
2731 * Locate an existing ppp channel.
2732 * The caller should have locked the all_channels_lock.
2733 * First we look in the new_channels list, then in the
2734 * all_channels list. If found in the new_channels list,
2735 * we move it to the all_channels list. This is for speed
2736 * when we have a lot of channels in use.
2738 static struct channel
*
2739 ppp_find_channel(struct ppp_net
*pn
, int unit
)
2741 struct channel
*pch
;
2743 list_for_each_entry(pch
, &pn
->new_channels
, list
) {
2744 if (pch
->file
.index
== unit
) {
2745 list_move(&pch
->list
, &pn
->all_channels
);
2750 list_for_each_entry(pch
, &pn
->all_channels
, list
) {
2751 if (pch
->file
.index
== unit
)
2759 * Connect a PPP channel to a PPP interface unit.
2762 ppp_connect_channel(struct channel
*pch
, int unit
)
2769 pn
= ppp_pernet(pch
->chan_net
);
2771 mutex_lock(&pn
->all_ppp_mutex
);
2772 ppp
= ppp_find_unit(pn
, unit
);
2775 write_lock_bh(&pch
->upl
);
2781 if (pch
->file
.hdrlen
> ppp
->file
.hdrlen
)
2782 ppp
->file
.hdrlen
= pch
->file
.hdrlen
;
2783 hdrlen
= pch
->file
.hdrlen
+ 2; /* for protocol bytes */
2784 if (hdrlen
> ppp
->dev
->hard_header_len
)
2785 ppp
->dev
->hard_header_len
= hdrlen
;
2786 list_add_tail(&pch
->clist
, &ppp
->channels
);
2789 atomic_inc(&ppp
->file
.refcnt
);
2794 write_unlock_bh(&pch
->upl
);
2796 mutex_unlock(&pn
->all_ppp_mutex
);
2801 * Disconnect a channel from its ppp unit.
2804 ppp_disconnect_channel(struct channel
*pch
)
2809 write_lock_bh(&pch
->upl
);
2812 write_unlock_bh(&pch
->upl
);
2814 /* remove it from the ppp unit's list */
2816 list_del(&pch
->clist
);
2817 if (--ppp
->n_channels
== 0)
2818 wake_up_interruptible(&ppp
->file
.rwait
);
2820 if (atomic_dec_and_test(&ppp
->file
.refcnt
))
2821 ppp_destroy_interface(ppp
);
2828 * Free up the resources used by a ppp channel.
2830 static void ppp_destroy_channel(struct channel
*pch
)
2832 atomic_dec(&channel_count
);
2834 if (!pch
->file
.dead
) {
2835 /* "can't happen" */
2836 printk(KERN_ERR
"ppp: destroying undead channel %p !\n",
2840 skb_queue_purge(&pch
->file
.xq
);
2841 skb_queue_purge(&pch
->file
.rq
);
2845 static void __exit
ppp_cleanup(void)
2847 /* should never happen */
2848 if (atomic_read(&ppp_unit_count
) || atomic_read(&channel_count
))
2849 printk(KERN_ERR
"PPP: removing module but units remain!\n");
2850 unregister_chrdev(PPP_MAJOR
, "ppp");
2851 device_destroy(ppp_class
, MKDEV(PPP_MAJOR
, 0));
2852 class_destroy(ppp_class
);
2853 unregister_pernet_device(&ppp_net_ops
);
2857 * Units handling. Caller must protect concurrent access
2858 * by holding all_ppp_mutex
2861 /* associate pointer with specified number */
2862 static int unit_set(struct idr
*p
, void *ptr
, int n
)
2867 if (!idr_pre_get(p
, GFP_KERNEL
)) {
2868 printk(KERN_ERR
"PPP: No free memory for idr\n");
2872 err
= idr_get_new_above(p
, ptr
, n
, &unit
);
2877 idr_remove(p
, unit
);
2884 /* get new free unit number and associate pointer with it */
2885 static int unit_get(struct idr
*p
, void *ptr
)
2890 if (!idr_pre_get(p
, GFP_KERNEL
)) {
2891 printk(KERN_ERR
"PPP: No free memory for idr\n");
2895 err
= idr_get_new_above(p
, ptr
, 0, &unit
);
2902 /* put unit number back to a pool */
2903 static void unit_put(struct idr
*p
, int n
)
2908 /* get pointer associated with the number */
2909 static void *unit_find(struct idr
*p
, int n
)
2911 return idr_find(p
, n
);
2914 /* Module/initialization stuff */
2916 module_init(ppp_init
);
2917 module_exit(ppp_cleanup
);
2919 EXPORT_SYMBOL(ppp_register_net_channel
);
2920 EXPORT_SYMBOL(ppp_register_channel
);
2921 EXPORT_SYMBOL(ppp_unregister_channel
);
2922 EXPORT_SYMBOL(ppp_channel_index
);
2923 EXPORT_SYMBOL(ppp_unit_number
);
2924 EXPORT_SYMBOL(ppp_dev_name
);
2925 EXPORT_SYMBOL(ppp_input
);
2926 EXPORT_SYMBOL(ppp_input_error
);
2927 EXPORT_SYMBOL(ppp_output_wakeup
);
2928 EXPORT_SYMBOL(ppp_register_compressor
);
2929 EXPORT_SYMBOL(ppp_unregister_compressor
);
2930 MODULE_LICENSE("GPL");
2931 MODULE_ALIAS_CHARDEV(PPP_MAJOR
, 0);
2932 MODULE_ALIAS("devname:ppp");