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 to hold primary network stats for which
98 * we want to use 64 bit storage. Other network stats
99 * are stored in dev->stats of the ppp strucute.
101 struct ppp_link_stats
{
109 * Data structure describing one ppp unit.
110 * A ppp unit corresponds to a ppp network interface device
111 * and represents a multilink bundle.
112 * It can have 0 or more ppp channels connected to it.
115 struct ppp_file file
; /* stuff for read/write/poll 0 */
116 struct file
*owner
; /* file that owns this unit 48 */
117 struct list_head channels
; /* list of attached channels 4c */
118 int n_channels
; /* how many channels are attached 54 */
119 spinlock_t rlock
; /* lock for receive side 58 */
120 spinlock_t wlock
; /* lock for transmit side 5c */
121 int mru
; /* max receive unit 60 */
122 unsigned int flags
; /* control bits 64 */
123 unsigned int xstate
; /* transmit state bits 68 */
124 unsigned int rstate
; /* receive state bits 6c */
125 int debug
; /* debug flags 70 */
126 struct slcompress
*vj
; /* state for VJ header compression */
127 enum NPmode npmode
[NUM_NP
]; /* what to do with each net proto 78 */
128 struct sk_buff
*xmit_pending
; /* a packet ready to go out 88 */
129 struct compressor
*xcomp
; /* transmit packet compressor 8c */
130 void *xc_state
; /* its internal state 90 */
131 struct compressor
*rcomp
; /* receive decompressor 94 */
132 void *rc_state
; /* its internal state 98 */
133 unsigned long last_xmit
; /* jiffies when last pkt sent 9c */
134 unsigned long last_recv
; /* jiffies when last pkt rcvd a0 */
135 struct net_device
*dev
; /* network interface device a4 */
136 int closing
; /* is device closing down? a8 */
137 #ifdef CONFIG_PPP_MULTILINK
138 int nxchan
; /* next channel to send something on */
139 u32 nxseq
; /* next sequence number to send */
140 int mrru
; /* MP: max reconst. receive unit */
141 u32 nextseq
; /* MP: seq no of next packet */
142 u32 minseq
; /* MP: min of most recent seqnos */
143 struct sk_buff_head mrq
; /* MP: receive reconstruction queue */
144 #endif /* CONFIG_PPP_MULTILINK */
145 #ifdef CONFIG_PPP_FILTER
146 struct bpf_prog
*pass_filter
; /* filter for packets to pass */
147 struct bpf_prog
*active_filter
; /* filter for pkts to reset idle */
148 #endif /* CONFIG_PPP_FILTER */
149 struct net
*ppp_net
; /* the net we belong to */
150 struct ppp_link_stats stats64
; /* 64 bit network stats */
154 * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
155 * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP,
157 * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR.
158 * Bits in xstate: SC_COMP_RUN
160 #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \
161 |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \
162 |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP)
165 * Private data structure for each channel.
166 * This includes the data structure used for multilink.
169 struct ppp_file file
; /* stuff for read/write/poll */
170 struct list_head list
; /* link in all/new_channels list */
171 struct ppp_channel
*chan
; /* public channel data structure */
172 struct rw_semaphore chan_sem
; /* protects `chan' during chan ioctl */
173 spinlock_t downl
; /* protects `chan', file.xq dequeue */
174 struct ppp
*ppp
; /* ppp unit we're connected to */
175 struct net
*chan_net
; /* the net channel belongs to */
176 struct list_head clist
; /* link in list of channels per unit */
177 rwlock_t upl
; /* protects `ppp' */
178 #ifdef CONFIG_PPP_MULTILINK
179 u8 avail
; /* flag used in multilink stuff */
180 u8 had_frag
; /* >= 1 fragments have been sent */
181 u32 lastseq
; /* MP: last sequence # received */
182 int speed
; /* speed of the corresponding ppp channel*/
183 #endif /* CONFIG_PPP_MULTILINK */
187 * SMP locking issues:
188 * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels
189 * list and the ppp.n_channels field, you need to take both locks
190 * before you modify them.
191 * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
195 static DEFINE_MUTEX(ppp_mutex
);
196 static atomic_t ppp_unit_count
= ATOMIC_INIT(0);
197 static atomic_t channel_count
= ATOMIC_INIT(0);
199 /* per-net private data for this module */
200 static int ppp_net_id __read_mostly
;
202 /* units to ppp mapping */
203 struct idr units_idr
;
206 * all_ppp_mutex protects the units_idr mapping.
207 * It also ensures that finding a ppp unit in the units_idr
208 * map and updating its file.refcnt field is atomic.
210 struct mutex all_ppp_mutex
;
213 struct list_head all_channels
;
214 struct list_head new_channels
;
215 int last_channel_index
;
218 * all_channels_lock protects all_channels and
219 * last_channel_index, and the atomicity of find
220 * a channel and updating its file.refcnt field.
222 spinlock_t all_channels_lock
;
225 /* Get the PPP protocol number from a skb */
226 #define PPP_PROTO(skb) get_unaligned_be16((skb)->data)
228 /* We limit the length of ppp->file.rq to this (arbitrary) value */
229 #define PPP_MAX_RQLEN 32
232 * Maximum number of multilink fragments queued up.
233 * This has to be large enough to cope with the maximum latency of
234 * the slowest channel relative to the others. Strictly it should
235 * depend on the number of channels and their characteristics.
237 #define PPP_MP_MAX_QLEN 128
239 /* Multilink header bits. */
240 #define B 0x80 /* this fragment begins a packet */
241 #define E 0x40 /* this fragment ends a packet */
243 /* Compare multilink sequence numbers (assumed to be 32 bits wide) */
244 #define seq_before(a, b) ((s32)((a) - (b)) < 0)
245 #define seq_after(a, b) ((s32)((a) - (b)) > 0)
248 static int ppp_unattached_ioctl(struct net
*net
, struct ppp_file
*pf
,
249 struct file
*file
, unsigned int cmd
, unsigned long arg
);
250 static void ppp_xmit_process(struct ppp
*ppp
);
251 static void ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
);
252 static void ppp_push(struct ppp
*ppp
);
253 static void ppp_channel_push(struct channel
*pch
);
254 static void ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
,
255 struct channel
*pch
);
256 static void ppp_receive_error(struct ppp
*ppp
);
257 static void ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
);
258 static struct sk_buff
*ppp_decompress_frame(struct ppp
*ppp
,
259 struct sk_buff
*skb
);
260 #ifdef CONFIG_PPP_MULTILINK
261 static void ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
,
262 struct channel
*pch
);
263 static void ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
);
264 static struct sk_buff
*ppp_mp_reconstruct(struct ppp
*ppp
);
265 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
);
266 #endif /* CONFIG_PPP_MULTILINK */
267 static int ppp_set_compress(struct ppp
*ppp
, unsigned long arg
);
268 static void ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
);
269 static void ppp_ccp_closed(struct ppp
*ppp
);
270 static struct compressor
*find_compressor(int type
);
271 static void ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
);
272 static struct ppp
*ppp_create_interface(struct net
*net
, int unit
, int *retp
);
273 static void init_ppp_file(struct ppp_file
*pf
, int kind
);
274 static void ppp_shutdown_interface(struct ppp
*ppp
);
275 static void ppp_destroy_interface(struct ppp
*ppp
);
276 static struct ppp
*ppp_find_unit(struct ppp_net
*pn
, int unit
);
277 static struct channel
*ppp_find_channel(struct ppp_net
*pn
, int unit
);
278 static int ppp_connect_channel(struct channel
*pch
, int unit
);
279 static int ppp_disconnect_channel(struct channel
*pch
);
280 static void ppp_destroy_channel(struct channel
*pch
);
281 static int unit_get(struct idr
*p
, void *ptr
);
282 static int unit_set(struct idr
*p
, void *ptr
, int n
);
283 static void unit_put(struct idr
*p
, int n
);
284 static void *unit_find(struct idr
*p
, int n
);
286 static struct class *ppp_class
;
288 /* per net-namespace data */
289 static inline struct ppp_net
*ppp_pernet(struct net
*net
)
293 return net_generic(net
, ppp_net_id
);
296 /* Translates a PPP protocol number to a NP index (NP == network protocol) */
297 static inline int proto_to_npindex(int proto
)
316 /* Translates an NP index into a PPP protocol number */
317 static const int npindex_to_proto
[NUM_NP
] = {
326 /* Translates an ethertype into an NP index */
327 static inline int ethertype_to_npindex(int ethertype
)
347 /* Translates an NP index into an ethertype */
348 static const int npindex_to_ethertype
[NUM_NP
] = {
360 #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock)
361 #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock)
362 #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock)
363 #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock)
364 #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \
365 ppp_recv_lock(ppp); } while (0)
366 #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \
367 ppp_xmit_unlock(ppp); } while (0)
370 * /dev/ppp device routines.
371 * The /dev/ppp device is used by pppd to control the ppp unit.
372 * It supports the read, write, ioctl and poll functions.
373 * Open instances of /dev/ppp can be in one of three states:
374 * unattached, attached to a ppp unit, or attached to a ppp channel.
376 static int ppp_open(struct inode
*inode
, struct file
*file
)
379 * This could (should?) be enforced by the permissions on /dev/ppp.
381 if (!capable(CAP_NET_ADMIN
))
386 static int ppp_release(struct inode
*unused
, struct file
*file
)
388 struct ppp_file
*pf
= file
->private_data
;
392 file
->private_data
= NULL
;
393 if (pf
->kind
== INTERFACE
) {
395 if (file
== ppp
->owner
)
396 ppp_shutdown_interface(ppp
);
398 if (atomic_dec_and_test(&pf
->refcnt
)) {
401 ppp_destroy_interface(PF_TO_PPP(pf
));
404 ppp_destroy_channel(PF_TO_CHANNEL(pf
));
412 static ssize_t
ppp_read(struct file
*file
, char __user
*buf
,
413 size_t count
, loff_t
*ppos
)
415 struct ppp_file
*pf
= file
->private_data
;
416 DECLARE_WAITQUEUE(wait
, current
);
418 struct sk_buff
*skb
= NULL
;
425 add_wait_queue(&pf
->rwait
, &wait
);
427 set_current_state(TASK_INTERRUPTIBLE
);
428 skb
= skb_dequeue(&pf
->rq
);
434 if (pf
->kind
== INTERFACE
) {
436 * Return 0 (EOF) on an interface that has no
437 * channels connected, unless it is looping
438 * network traffic (demand mode).
440 struct ppp
*ppp
= PF_TO_PPP(pf
);
441 if (ppp
->n_channels
== 0 &&
442 (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0)
446 if (file
->f_flags
& O_NONBLOCK
)
449 if (signal_pending(current
))
453 set_current_state(TASK_RUNNING
);
454 remove_wait_queue(&pf
->rwait
, &wait
);
460 if (skb
->len
> count
)
465 if (skb_copy_datagram_iovec(skb
, 0, &iov
, skb
->len
))
475 static ssize_t
ppp_write(struct file
*file
, const char __user
*buf
,
476 size_t count
, loff_t
*ppos
)
478 struct ppp_file
*pf
= file
->private_data
;
485 skb
= alloc_skb(count
+ pf
->hdrlen
, GFP_KERNEL
);
488 skb_reserve(skb
, pf
->hdrlen
);
490 if (copy_from_user(skb_put(skb
, count
), buf
, count
)) {
495 skb_queue_tail(&pf
->xq
, skb
);
499 ppp_xmit_process(PF_TO_PPP(pf
));
502 ppp_channel_push(PF_TO_CHANNEL(pf
));
512 /* No kernel lock - fine */
513 static unsigned int ppp_poll(struct file
*file
, poll_table
*wait
)
515 struct ppp_file
*pf
= file
->private_data
;
520 poll_wait(file
, &pf
->rwait
, wait
);
521 mask
= POLLOUT
| POLLWRNORM
;
522 if (skb_peek(&pf
->rq
))
523 mask
|= POLLIN
| POLLRDNORM
;
526 else if (pf
->kind
== INTERFACE
) {
527 /* see comment in ppp_read */
528 struct ppp
*ppp
= PF_TO_PPP(pf
);
529 if (ppp
->n_channels
== 0 &&
530 (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0)
531 mask
|= POLLIN
| POLLRDNORM
;
537 #ifdef CONFIG_PPP_FILTER
538 static int get_filter(void __user
*arg
, struct sock_filter
**p
)
540 struct sock_fprog uprog
;
541 struct sock_filter
*code
= NULL
;
544 if (copy_from_user(&uprog
, arg
, sizeof(uprog
)))
552 len
= uprog
.len
* sizeof(struct sock_filter
);
553 code
= memdup_user(uprog
.filter
, len
);
555 return PTR_ERR(code
);
560 #endif /* CONFIG_PPP_FILTER */
562 static long ppp_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
564 struct ppp_file
*pf
= file
->private_data
;
566 int err
= -EFAULT
, val
, val2
, i
;
567 struct ppp_idle idle
;
570 struct slcompress
*vj
;
571 void __user
*argp
= (void __user
*)arg
;
572 int __user
*p
= argp
;
575 return ppp_unattached_ioctl(current
->nsproxy
->net_ns
,
578 if (cmd
== PPPIOCDETACH
) {
580 * We have to be careful here... if the file descriptor
581 * has been dup'd, we could have another process in the
582 * middle of a poll using the same file *, so we had
583 * better not free the interface data structures -
584 * instead we fail the ioctl. Even in this case, we
585 * shut down the interface if we are the owner of it.
586 * Actually, we should get rid of PPPIOCDETACH, userland
587 * (i.e. pppd) could achieve the same effect by closing
588 * this fd and reopening /dev/ppp.
591 mutex_lock(&ppp_mutex
);
592 if (pf
->kind
== INTERFACE
) {
594 if (file
== ppp
->owner
)
595 ppp_shutdown_interface(ppp
);
597 if (atomic_long_read(&file
->f_count
) < 2) {
598 ppp_release(NULL
, file
);
601 pr_warn("PPPIOCDETACH file->f_count=%ld\n",
602 atomic_long_read(&file
->f_count
));
603 mutex_unlock(&ppp_mutex
);
607 if (pf
->kind
== CHANNEL
) {
609 struct ppp_channel
*chan
;
611 mutex_lock(&ppp_mutex
);
612 pch
= PF_TO_CHANNEL(pf
);
616 if (get_user(unit
, p
))
618 err
= ppp_connect_channel(pch
, unit
);
622 err
= ppp_disconnect_channel(pch
);
626 down_read(&pch
->chan_sem
);
629 if (chan
&& chan
->ops
->ioctl
)
630 err
= chan
->ops
->ioctl(chan
, cmd
, arg
);
631 up_read(&pch
->chan_sem
);
633 mutex_unlock(&ppp_mutex
);
637 if (pf
->kind
!= INTERFACE
) {
639 pr_err("PPP: not interface or channel??\n");
643 mutex_lock(&ppp_mutex
);
647 if (get_user(val
, p
))
654 if (get_user(val
, p
))
657 cflags
= ppp
->flags
& ~val
;
658 #ifdef CONFIG_PPP_MULTILINK
659 if (!(ppp
->flags
& SC_MULTILINK
) && (val
& SC_MULTILINK
))
662 ppp
->flags
= val
& SC_FLAG_BITS
;
664 if (cflags
& SC_CCP_OPEN
)
670 val
= ppp
->flags
| ppp
->xstate
| ppp
->rstate
;
671 if (put_user(val
, p
))
676 case PPPIOCSCOMPRESS
:
677 err
= ppp_set_compress(ppp
, arg
);
681 if (put_user(ppp
->file
.index
, p
))
687 if (get_user(val
, p
))
694 if (put_user(ppp
->debug
, p
))
700 idle
.xmit_idle
= (jiffies
- ppp
->last_xmit
) / HZ
;
701 idle
.recv_idle
= (jiffies
- ppp
->last_recv
) / HZ
;
702 if (copy_to_user(argp
, &idle
, sizeof(idle
)))
708 if (get_user(val
, p
))
711 if ((val
>> 16) != 0) {
715 vj
= slhc_init(val2
+1, val
+1);
718 "PPP: no memory (VJ compressor)\n");
732 if (copy_from_user(&npi
, argp
, sizeof(npi
)))
734 err
= proto_to_npindex(npi
.protocol
);
738 if (cmd
== PPPIOCGNPMODE
) {
740 npi
.mode
= ppp
->npmode
[i
];
741 if (copy_to_user(argp
, &npi
, sizeof(npi
)))
744 ppp
->npmode
[i
] = npi
.mode
;
745 /* we may be able to transmit more packets now (??) */
746 netif_wake_queue(ppp
->dev
);
751 #ifdef CONFIG_PPP_FILTER
754 struct sock_filter
*code
;
756 err
= get_filter(argp
, &code
);
758 struct sock_fprog_kern fprog
= {
764 if (ppp
->pass_filter
) {
765 bpf_prog_destroy(ppp
->pass_filter
);
766 ppp
->pass_filter
= NULL
;
768 if (fprog
.filter
!= NULL
)
769 err
= bpf_prog_create(&ppp
->pass_filter
,
780 struct sock_filter
*code
;
782 err
= get_filter(argp
, &code
);
784 struct sock_fprog_kern fprog
= {
790 if (ppp
->active_filter
) {
791 bpf_prog_destroy(ppp
->active_filter
);
792 ppp
->active_filter
= NULL
;
794 if (fprog
.filter
!= NULL
)
795 err
= bpf_prog_create(&ppp
->active_filter
,
804 #endif /* CONFIG_PPP_FILTER */
806 #ifdef CONFIG_PPP_MULTILINK
808 if (get_user(val
, p
))
812 ppp_recv_unlock(ppp
);
815 #endif /* CONFIG_PPP_MULTILINK */
820 mutex_unlock(&ppp_mutex
);
824 static int ppp_unattached_ioctl(struct net
*net
, struct ppp_file
*pf
,
825 struct file
*file
, unsigned int cmd
, unsigned long arg
)
827 int unit
, err
= -EFAULT
;
829 struct channel
*chan
;
831 int __user
*p
= (int __user
*)arg
;
833 mutex_lock(&ppp_mutex
);
836 /* Create a new ppp unit */
837 if (get_user(unit
, p
))
839 ppp
= ppp_create_interface(net
, unit
, &err
);
842 file
->private_data
= &ppp
->file
;
845 if (put_user(ppp
->file
.index
, p
))
851 /* Attach to an existing ppp unit */
852 if (get_user(unit
, p
))
855 pn
= ppp_pernet(net
);
856 mutex_lock(&pn
->all_ppp_mutex
);
857 ppp
= ppp_find_unit(pn
, unit
);
859 atomic_inc(&ppp
->file
.refcnt
);
860 file
->private_data
= &ppp
->file
;
863 mutex_unlock(&pn
->all_ppp_mutex
);
867 if (get_user(unit
, p
))
870 pn
= ppp_pernet(net
);
871 spin_lock_bh(&pn
->all_channels_lock
);
872 chan
= ppp_find_channel(pn
, unit
);
874 atomic_inc(&chan
->file
.refcnt
);
875 file
->private_data
= &chan
->file
;
878 spin_unlock_bh(&pn
->all_channels_lock
);
884 mutex_unlock(&ppp_mutex
);
888 static const struct file_operations ppp_device_fops
= {
889 .owner
= THIS_MODULE
,
893 .unlocked_ioctl
= ppp_ioctl
,
895 .release
= ppp_release
,
896 .llseek
= noop_llseek
,
899 static __net_init
int ppp_init_net(struct net
*net
)
901 struct ppp_net
*pn
= net_generic(net
, ppp_net_id
);
903 idr_init(&pn
->units_idr
);
904 mutex_init(&pn
->all_ppp_mutex
);
906 INIT_LIST_HEAD(&pn
->all_channels
);
907 INIT_LIST_HEAD(&pn
->new_channels
);
909 spin_lock_init(&pn
->all_channels_lock
);
914 static __net_exit
void ppp_exit_net(struct net
*net
)
916 struct ppp_net
*pn
= net_generic(net
, ppp_net_id
);
918 idr_destroy(&pn
->units_idr
);
921 static struct pernet_operations ppp_net_ops
= {
922 .init
= ppp_init_net
,
923 .exit
= ppp_exit_net
,
925 .size
= sizeof(struct ppp_net
),
928 #define PPP_MAJOR 108
930 /* Called at boot time if ppp is compiled into the kernel,
931 or at module load time (from init_module) if compiled as a module. */
932 static int __init
ppp_init(void)
936 pr_info("PPP generic driver version " PPP_VERSION
"\n");
938 err
= register_pernet_device(&ppp_net_ops
);
940 pr_err("failed to register PPP pernet device (%d)\n", err
);
944 err
= register_chrdev(PPP_MAJOR
, "ppp", &ppp_device_fops
);
946 pr_err("failed to register PPP device (%d)\n", err
);
950 ppp_class
= class_create(THIS_MODULE
, "ppp");
951 if (IS_ERR(ppp_class
)) {
952 err
= PTR_ERR(ppp_class
);
956 /* not a big deal if we fail here :-) */
957 device_create(ppp_class
, NULL
, MKDEV(PPP_MAJOR
, 0), NULL
, "ppp");
962 unregister_chrdev(PPP_MAJOR
, "ppp");
964 unregister_pernet_device(&ppp_net_ops
);
970 * Network interface unit routines.
973 ppp_start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
975 struct ppp
*ppp
= netdev_priv(dev
);
979 npi
= ethertype_to_npindex(ntohs(skb
->protocol
));
983 /* Drop, accept or reject the packet */
984 switch (ppp
->npmode
[npi
]) {
988 /* it would be nice to have a way to tell the network
989 system to queue this one up for later. */
996 /* Put the 2-byte PPP protocol number on the front,
997 making sure there is room for the address and control fields. */
998 if (skb_cow_head(skb
, PPP_HDRLEN
))
1001 pp
= skb_push(skb
, 2);
1002 proto
= npindex_to_proto
[npi
];
1003 put_unaligned_be16(proto
, pp
);
1005 skb_queue_tail(&ppp
->file
.xq
, skb
);
1006 ppp_xmit_process(ppp
);
1007 return NETDEV_TX_OK
;
1011 ++dev
->stats
.tx_dropped
;
1012 return NETDEV_TX_OK
;
1016 ppp_net_ioctl(struct net_device
*dev
, struct ifreq
*ifr
, int cmd
)
1018 struct ppp
*ppp
= netdev_priv(dev
);
1020 void __user
*addr
= (void __user
*) ifr
->ifr_ifru
.ifru_data
;
1021 struct ppp_stats stats
;
1022 struct ppp_comp_stats cstats
;
1027 ppp_get_stats(ppp
, &stats
);
1028 if (copy_to_user(addr
, &stats
, sizeof(stats
)))
1033 case SIOCGPPPCSTATS
:
1034 memset(&cstats
, 0, sizeof(cstats
));
1036 ppp
->xcomp
->comp_stat(ppp
->xc_state
, &cstats
.c
);
1038 ppp
->rcomp
->decomp_stat(ppp
->rc_state
, &cstats
.d
);
1039 if (copy_to_user(addr
, &cstats
, sizeof(cstats
)))
1046 if (copy_to_user(addr
, vers
, strlen(vers
) + 1))
1058 static struct rtnl_link_stats64
*
1059 ppp_get_stats64(struct net_device
*dev
, struct rtnl_link_stats64
*stats64
)
1061 struct ppp
*ppp
= netdev_priv(dev
);
1064 stats64
->rx_packets
= ppp
->stats64
.rx_packets
;
1065 stats64
->rx_bytes
= ppp
->stats64
.rx_bytes
;
1066 ppp_recv_unlock(ppp
);
1069 stats64
->tx_packets
= ppp
->stats64
.tx_packets
;
1070 stats64
->tx_bytes
= ppp
->stats64
.tx_bytes
;
1071 ppp_xmit_unlock(ppp
);
1073 stats64
->rx_errors
= dev
->stats
.rx_errors
;
1074 stats64
->tx_errors
= dev
->stats
.tx_errors
;
1075 stats64
->rx_dropped
= dev
->stats
.rx_dropped
;
1076 stats64
->tx_dropped
= dev
->stats
.tx_dropped
;
1077 stats64
->rx_length_errors
= dev
->stats
.rx_length_errors
;
1082 static struct lock_class_key ppp_tx_busylock
;
1083 static int ppp_dev_init(struct net_device
*dev
)
1085 dev
->qdisc_tx_busylock
= &ppp_tx_busylock
;
1089 static const struct net_device_ops ppp_netdev_ops
= {
1090 .ndo_init
= ppp_dev_init
,
1091 .ndo_start_xmit
= ppp_start_xmit
,
1092 .ndo_do_ioctl
= ppp_net_ioctl
,
1093 .ndo_get_stats64
= ppp_get_stats64
,
1096 static void ppp_setup(struct net_device
*dev
)
1098 dev
->netdev_ops
= &ppp_netdev_ops
;
1099 dev
->hard_header_len
= PPP_HDRLEN
;
1102 dev
->tx_queue_len
= 3;
1103 dev
->type
= ARPHRD_PPP
;
1104 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
1105 dev
->features
|= NETIF_F_NETNS_LOCAL
;
1106 netif_keep_dst(dev
);
1110 * Transmit-side routines.
1114 * Called to do any work queued up on the transmit side
1115 * that can now be done.
1118 ppp_xmit_process(struct ppp
*ppp
)
1120 struct sk_buff
*skb
;
1123 if (!ppp
->closing
) {
1125 while (!ppp
->xmit_pending
&&
1126 (skb
= skb_dequeue(&ppp
->file
.xq
)))
1127 ppp_send_frame(ppp
, skb
);
1128 /* If there's no work left to do, tell the core net
1129 code that we can accept some more. */
1130 if (!ppp
->xmit_pending
&& !skb_peek(&ppp
->file
.xq
))
1131 netif_wake_queue(ppp
->dev
);
1133 netif_stop_queue(ppp
->dev
);
1135 ppp_xmit_unlock(ppp
);
1138 static inline struct sk_buff
*
1139 pad_compress_skb(struct ppp
*ppp
, struct sk_buff
*skb
)
1141 struct sk_buff
*new_skb
;
1143 int new_skb_size
= ppp
->dev
->mtu
+
1144 ppp
->xcomp
->comp_extra
+ ppp
->dev
->hard_header_len
;
1145 int compressor_skb_size
= ppp
->dev
->mtu
+
1146 ppp
->xcomp
->comp_extra
+ PPP_HDRLEN
;
1147 new_skb
= alloc_skb(new_skb_size
, GFP_ATOMIC
);
1149 if (net_ratelimit())
1150 netdev_err(ppp
->dev
, "PPP: no memory (comp pkt)\n");
1153 if (ppp
->dev
->hard_header_len
> PPP_HDRLEN
)
1154 skb_reserve(new_skb
,
1155 ppp
->dev
->hard_header_len
- PPP_HDRLEN
);
1157 /* compressor still expects A/C bytes in hdr */
1158 len
= ppp
->xcomp
->compress(ppp
->xc_state
, skb
->data
- 2,
1159 new_skb
->data
, skb
->len
+ 2,
1160 compressor_skb_size
);
1161 if (len
> 0 && (ppp
->flags
& SC_CCP_UP
)) {
1165 skb_pull(skb
, 2); /* pull off A/C bytes */
1166 } else if (len
== 0) {
1167 /* didn't compress, or CCP not up yet */
1168 consume_skb(new_skb
);
1173 * MPPE requires that we do not send unencrypted
1174 * frames. The compressor will return -1 if we
1175 * should drop the frame. We cannot simply test
1176 * the compress_proto because MPPE and MPPC share
1179 if (net_ratelimit())
1180 netdev_err(ppp
->dev
, "ppp: compressor dropped pkt\n");
1182 consume_skb(new_skb
);
1189 * Compress and send a frame.
1190 * The caller should have locked the xmit path,
1191 * and xmit_pending should be 0.
1194 ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1196 int proto
= PPP_PROTO(skb
);
1197 struct sk_buff
*new_skb
;
1201 if (proto
< 0x8000) {
1202 #ifdef CONFIG_PPP_FILTER
1203 /* check if we should pass this packet */
1204 /* the filter instructions are constructed assuming
1205 a four-byte PPP header on each packet */
1206 *skb_push(skb
, 2) = 1;
1207 if (ppp
->pass_filter
&&
1208 BPF_PROG_RUN(ppp
->pass_filter
, skb
) == 0) {
1210 netdev_printk(KERN_DEBUG
, ppp
->dev
,
1211 "PPP: outbound frame "
1216 /* if this packet passes the active filter, record the time */
1217 if (!(ppp
->active_filter
&&
1218 BPF_PROG_RUN(ppp
->active_filter
, skb
) == 0))
1219 ppp
->last_xmit
= jiffies
;
1222 /* for data packets, record the time */
1223 ppp
->last_xmit
= jiffies
;
1224 #endif /* CONFIG_PPP_FILTER */
1227 ++ppp
->stats64
.tx_packets
;
1228 ppp
->stats64
.tx_bytes
+= skb
->len
- 2;
1232 if (!ppp
->vj
|| (ppp
->flags
& SC_COMP_TCP
) == 0)
1234 /* try to do VJ TCP header compression */
1235 new_skb
= alloc_skb(skb
->len
+ ppp
->dev
->hard_header_len
- 2,
1238 netdev_err(ppp
->dev
, "PPP: no memory (VJ comp pkt)\n");
1241 skb_reserve(new_skb
, ppp
->dev
->hard_header_len
- 2);
1243 len
= slhc_compress(ppp
->vj
, cp
, skb
->len
- 2,
1244 new_skb
->data
+ 2, &cp
,
1245 !(ppp
->flags
& SC_NO_TCP_CCID
));
1246 if (cp
== skb
->data
+ 2) {
1247 /* didn't compress */
1248 consume_skb(new_skb
);
1250 if (cp
[0] & SL_TYPE_COMPRESSED_TCP
) {
1251 proto
= PPP_VJC_COMP
;
1252 cp
[0] &= ~SL_TYPE_COMPRESSED_TCP
;
1254 proto
= PPP_VJC_UNCOMP
;
1255 cp
[0] = skb
->data
[2];
1259 cp
= skb_put(skb
, len
+ 2);
1266 /* peek at outbound CCP frames */
1267 ppp_ccp_peek(ppp
, skb
, 0);
1271 /* try to do packet compression */
1272 if ((ppp
->xstate
& SC_COMP_RUN
) && ppp
->xc_state
&&
1273 proto
!= PPP_LCP
&& proto
!= PPP_CCP
) {
1274 if (!(ppp
->flags
& SC_CCP_UP
) && (ppp
->flags
& SC_MUST_COMP
)) {
1275 if (net_ratelimit())
1276 netdev_err(ppp
->dev
,
1277 "ppp: compression required but "
1278 "down - pkt dropped.\n");
1281 skb
= pad_compress_skb(ppp
, skb
);
1287 * If we are waiting for traffic (demand dialling),
1288 * queue it up for pppd to receive.
1290 if (ppp
->flags
& SC_LOOP_TRAFFIC
) {
1291 if (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
)
1293 skb_queue_tail(&ppp
->file
.rq
, skb
);
1294 wake_up_interruptible(&ppp
->file
.rwait
);
1298 ppp
->xmit_pending
= skb
;
1304 ++ppp
->dev
->stats
.tx_errors
;
1308 * Try to send the frame in xmit_pending.
1309 * The caller should have the xmit path locked.
1312 ppp_push(struct ppp
*ppp
)
1314 struct list_head
*list
;
1315 struct channel
*pch
;
1316 struct sk_buff
*skb
= ppp
->xmit_pending
;
1321 list
= &ppp
->channels
;
1322 if (list_empty(list
)) {
1323 /* nowhere to send the packet, just drop it */
1324 ppp
->xmit_pending
= NULL
;
1329 if ((ppp
->flags
& SC_MULTILINK
) == 0) {
1330 /* not doing multilink: send it down the first channel */
1332 pch
= list_entry(list
, struct channel
, clist
);
1334 spin_lock_bh(&pch
->downl
);
1336 if (pch
->chan
->ops
->start_xmit(pch
->chan
, skb
))
1337 ppp
->xmit_pending
= NULL
;
1339 /* channel got unregistered */
1341 ppp
->xmit_pending
= NULL
;
1343 spin_unlock_bh(&pch
->downl
);
1347 #ifdef CONFIG_PPP_MULTILINK
1348 /* Multilink: fragment the packet over as many links
1349 as can take the packet at the moment. */
1350 if (!ppp_mp_explode(ppp
, skb
))
1352 #endif /* CONFIG_PPP_MULTILINK */
1354 ppp
->xmit_pending
= NULL
;
1358 #ifdef CONFIG_PPP_MULTILINK
1359 static bool mp_protocol_compress __read_mostly
= true;
1360 module_param(mp_protocol_compress
, bool, S_IRUGO
| S_IWUSR
);
1361 MODULE_PARM_DESC(mp_protocol_compress
,
1362 "compress protocol id in multilink fragments");
1365 * Divide a packet to be transmitted into fragments and
1366 * send them out the individual links.
1368 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
)
1371 int i
, bits
, hdrlen
, mtu
;
1373 int navail
, nfree
, nzero
;
1377 unsigned char *p
, *q
;
1378 struct list_head
*list
;
1379 struct channel
*pch
;
1380 struct sk_buff
*frag
;
1381 struct ppp_channel
*chan
;
1383 totspeed
= 0; /*total bitrate of the bundle*/
1384 nfree
= 0; /* # channels which have no packet already queued */
1385 navail
= 0; /* total # of usable channels (not deregistered) */
1386 nzero
= 0; /* number of channels with zero speed associated*/
1387 totfree
= 0; /*total # of channels available and
1388 *having no queued packets before
1389 *starting the fragmentation*/
1391 hdrlen
= (ppp
->flags
& SC_MP_XSHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1393 list_for_each_entry(pch
, &ppp
->channels
, clist
) {
1397 pch
->speed
= pch
->chan
->speed
;
1402 if (skb_queue_empty(&pch
->file
.xq
) ||
1404 if (pch
->speed
== 0)
1407 totspeed
+= pch
->speed
;
1413 if (!pch
->had_frag
&& i
< ppp
->nxchan
)
1419 * Don't start sending this packet unless at least half of
1420 * the channels are free. This gives much better TCP
1421 * performance if we have a lot of channels.
1423 if (nfree
== 0 || nfree
< navail
/ 2)
1424 return 0; /* can't take now, leave it in xmit_pending */
1426 /* Do protocol field compression */
1429 if (*p
== 0 && mp_protocol_compress
) {
1435 nbigger
= len
% nfree
;
1437 /* skip to the channel after the one we last used
1438 and start at that one */
1439 list
= &ppp
->channels
;
1440 for (i
= 0; i
< ppp
->nxchan
; ++i
) {
1442 if (list
== &ppp
->channels
) {
1448 /* create a fragment for each channel */
1452 if (list
== &ppp
->channels
) {
1456 pch
= list_entry(list
, struct channel
, clist
);
1462 * Skip this channel if it has a fragment pending already and
1463 * we haven't given a fragment to all of the free channels.
1465 if (pch
->avail
== 1) {
1472 /* check the channel's mtu and whether it is still attached. */
1473 spin_lock_bh(&pch
->downl
);
1474 if (pch
->chan
== NULL
) {
1475 /* can't use this channel, it's being deregistered */
1476 if (pch
->speed
== 0)
1479 totspeed
-= pch
->speed
;
1481 spin_unlock_bh(&pch
->downl
);
1492 *if the channel speed is not set divide
1493 *the packet evenly among the free channels;
1494 *otherwise divide it according to the speed
1495 *of the channel we are going to transmit on
1499 if (pch
->speed
== 0) {
1506 flen
= (((totfree
- nzero
)*(totlen
+ hdrlen
*totfree
)) /
1507 ((totspeed
*totfree
)/pch
->speed
)) - hdrlen
;
1509 flen
+= ((totfree
- nzero
)*pch
->speed
)/totspeed
;
1510 nbigger
-= ((totfree
- nzero
)*pch
->speed
)/
1518 *check if we are on the last channel or
1519 *we exceded the length of the data to
1522 if ((nfree
<= 0) || (flen
> len
))
1525 *it is not worth to tx on slow channels:
1526 *in that case from the resulting flen according to the
1527 *above formula will be equal or less than zero.
1528 *Skip the channel in this case
1532 spin_unlock_bh(&pch
->downl
);
1537 * hdrlen includes the 2-byte PPP protocol field, but the
1538 * MTU counts only the payload excluding the protocol field.
1539 * (RFC1661 Section 2)
1541 mtu
= pch
->chan
->mtu
- (hdrlen
- 2);
1548 frag
= alloc_skb(flen
+ hdrlen
+ (flen
== 0), GFP_ATOMIC
);
1551 q
= skb_put(frag
, flen
+ hdrlen
);
1553 /* make the MP header */
1554 put_unaligned_be16(PPP_MP
, q
);
1555 if (ppp
->flags
& SC_MP_XSHORTSEQ
) {
1556 q
[2] = bits
+ ((ppp
->nxseq
>> 8) & 0xf);
1560 q
[3] = ppp
->nxseq
>> 16;
1561 q
[4] = ppp
->nxseq
>> 8;
1565 memcpy(q
+ hdrlen
, p
, flen
);
1567 /* try to send it down the channel */
1569 if (!skb_queue_empty(&pch
->file
.xq
) ||
1570 !chan
->ops
->start_xmit(chan
, frag
))
1571 skb_queue_tail(&pch
->file
.xq
, frag
);
1577 spin_unlock_bh(&pch
->downl
);
1584 spin_unlock_bh(&pch
->downl
);
1586 netdev_err(ppp
->dev
, "PPP: no memory (fragment)\n");
1587 ++ppp
->dev
->stats
.tx_errors
;
1589 return 1; /* abandon the frame */
1591 #endif /* CONFIG_PPP_MULTILINK */
1594 * Try to send data out on a channel.
1597 ppp_channel_push(struct channel
*pch
)
1599 struct sk_buff
*skb
;
1602 spin_lock_bh(&pch
->downl
);
1604 while (!skb_queue_empty(&pch
->file
.xq
)) {
1605 skb
= skb_dequeue(&pch
->file
.xq
);
1606 if (!pch
->chan
->ops
->start_xmit(pch
->chan
, skb
)) {
1607 /* put the packet back and try again later */
1608 skb_queue_head(&pch
->file
.xq
, skb
);
1613 /* channel got deregistered */
1614 skb_queue_purge(&pch
->file
.xq
);
1616 spin_unlock_bh(&pch
->downl
);
1617 /* see if there is anything from the attached unit to be sent */
1618 if (skb_queue_empty(&pch
->file
.xq
)) {
1619 read_lock_bh(&pch
->upl
);
1622 ppp_xmit_process(ppp
);
1623 read_unlock_bh(&pch
->upl
);
1628 * Receive-side routines.
1631 struct ppp_mp_skb_parm
{
1635 #define PPP_MP_CB(skb) ((struct ppp_mp_skb_parm *)((skb)->cb))
1638 ppp_do_recv(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1642 ppp_receive_frame(ppp
, skb
, pch
);
1645 ppp_recv_unlock(ppp
);
1649 ppp_input(struct ppp_channel
*chan
, struct sk_buff
*skb
)
1651 struct channel
*pch
= chan
->ppp
;
1659 read_lock_bh(&pch
->upl
);
1660 if (!pskb_may_pull(skb
, 2)) {
1663 ++pch
->ppp
->dev
->stats
.rx_length_errors
;
1664 ppp_receive_error(pch
->ppp
);
1669 proto
= PPP_PROTO(skb
);
1670 if (!pch
->ppp
|| proto
>= 0xc000 || proto
== PPP_CCPFRAG
) {
1671 /* put it on the channel queue */
1672 skb_queue_tail(&pch
->file
.rq
, skb
);
1673 /* drop old frames if queue too long */
1674 while (pch
->file
.rq
.qlen
> PPP_MAX_RQLEN
&&
1675 (skb
= skb_dequeue(&pch
->file
.rq
)))
1677 wake_up_interruptible(&pch
->file
.rwait
);
1679 ppp_do_recv(pch
->ppp
, skb
, pch
);
1683 read_unlock_bh(&pch
->upl
);
1686 /* Put a 0-length skb in the receive queue as an error indication */
1688 ppp_input_error(struct ppp_channel
*chan
, int code
)
1690 struct channel
*pch
= chan
->ppp
;
1691 struct sk_buff
*skb
;
1696 read_lock_bh(&pch
->upl
);
1698 skb
= alloc_skb(0, GFP_ATOMIC
);
1700 skb
->len
= 0; /* probably unnecessary */
1702 ppp_do_recv(pch
->ppp
, skb
, pch
);
1705 read_unlock_bh(&pch
->upl
);
1709 * We come in here to process a received frame.
1710 * The receive side of the ppp unit is locked.
1713 ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1715 /* note: a 0-length skb is used as an error indication */
1717 #ifdef CONFIG_PPP_MULTILINK
1718 /* XXX do channel-level decompression here */
1719 if (PPP_PROTO(skb
) == PPP_MP
)
1720 ppp_receive_mp_frame(ppp
, skb
, pch
);
1722 #endif /* CONFIG_PPP_MULTILINK */
1723 ppp_receive_nonmp_frame(ppp
, skb
);
1726 ppp_receive_error(ppp
);
1731 ppp_receive_error(struct ppp
*ppp
)
1733 ++ppp
->dev
->stats
.rx_errors
;
1739 ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1742 int proto
, len
, npi
;
1745 * Decompress the frame, if compressed.
1746 * Note that some decompressors need to see uncompressed frames
1747 * that come in as well as compressed frames.
1749 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
) &&
1750 (ppp
->rstate
& (SC_DC_FERROR
| SC_DC_ERROR
)) == 0)
1751 skb
= ppp_decompress_frame(ppp
, skb
);
1753 if (ppp
->flags
& SC_MUST_COMP
&& ppp
->rstate
& SC_DC_FERROR
)
1756 proto
= PPP_PROTO(skb
);
1759 /* decompress VJ compressed packets */
1760 if (!ppp
->vj
|| (ppp
->flags
& SC_REJ_COMP_TCP
))
1763 if (skb_tailroom(skb
) < 124 || skb_cloned(skb
)) {
1764 /* copy to a new sk_buff with more tailroom */
1765 ns
= dev_alloc_skb(skb
->len
+ 128);
1767 netdev_err(ppp
->dev
, "PPP: no memory "
1772 skb_copy_bits(skb
, 0, skb_put(ns
, skb
->len
), skb
->len
);
1777 skb
->ip_summed
= CHECKSUM_NONE
;
1779 len
= slhc_uncompress(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2);
1781 netdev_printk(KERN_DEBUG
, ppp
->dev
,
1782 "PPP: VJ decompression error\n");
1787 skb_put(skb
, len
- skb
->len
);
1788 else if (len
< skb
->len
)
1793 case PPP_VJC_UNCOMP
:
1794 if (!ppp
->vj
|| (ppp
->flags
& SC_REJ_COMP_TCP
))
1797 /* Until we fix the decompressor need to make sure
1798 * data portion is linear.
1800 if (!pskb_may_pull(skb
, skb
->len
))
1803 if (slhc_remember(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2) <= 0) {
1804 netdev_err(ppp
->dev
, "PPP: VJ uncompressed error\n");
1811 ppp_ccp_peek(ppp
, skb
, 1);
1815 ++ppp
->stats64
.rx_packets
;
1816 ppp
->stats64
.rx_bytes
+= skb
->len
- 2;
1818 npi
= proto_to_npindex(proto
);
1820 /* control or unknown frame - pass it to pppd */
1821 skb_queue_tail(&ppp
->file
.rq
, skb
);
1822 /* limit queue length by dropping old frames */
1823 while (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
&&
1824 (skb
= skb_dequeue(&ppp
->file
.rq
)))
1826 /* wake up any process polling or blocking on read */
1827 wake_up_interruptible(&ppp
->file
.rwait
);
1830 /* network protocol frame - give it to the kernel */
1832 #ifdef CONFIG_PPP_FILTER
1833 /* check if the packet passes the pass and active filters */
1834 /* the filter instructions are constructed assuming
1835 a four-byte PPP header on each packet */
1836 if (ppp
->pass_filter
|| ppp
->active_filter
) {
1837 if (skb_unclone(skb
, GFP_ATOMIC
))
1840 *skb_push(skb
, 2) = 0;
1841 if (ppp
->pass_filter
&&
1842 BPF_PROG_RUN(ppp
->pass_filter
, skb
) == 0) {
1844 netdev_printk(KERN_DEBUG
, ppp
->dev
,
1845 "PPP: inbound frame "
1850 if (!(ppp
->active_filter
&&
1851 BPF_PROG_RUN(ppp
->active_filter
, skb
) == 0))
1852 ppp
->last_recv
= jiffies
;
1855 #endif /* CONFIG_PPP_FILTER */
1856 ppp
->last_recv
= jiffies
;
1858 if ((ppp
->dev
->flags
& IFF_UP
) == 0 ||
1859 ppp
->npmode
[npi
] != NPMODE_PASS
) {
1862 /* chop off protocol */
1863 skb_pull_rcsum(skb
, 2);
1864 skb
->dev
= ppp
->dev
;
1865 skb
->protocol
= htons(npindex_to_ethertype
[npi
]);
1866 skb_reset_mac_header(skb
);
1874 ppp_receive_error(ppp
);
1877 static struct sk_buff
*
1878 ppp_decompress_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1880 int proto
= PPP_PROTO(skb
);
1884 /* Until we fix all the decompressor's need to make sure
1885 * data portion is linear.
1887 if (!pskb_may_pull(skb
, skb
->len
))
1890 if (proto
== PPP_COMP
) {
1893 switch(ppp
->rcomp
->compress_proto
) {
1895 obuff_size
= ppp
->mru
+ PPP_HDRLEN
+ 1;
1898 obuff_size
= ppp
->mru
+ PPP_HDRLEN
;
1902 ns
= dev_alloc_skb(obuff_size
);
1904 netdev_err(ppp
->dev
, "ppp_decompress_frame: "
1908 /* the decompressor still expects the A/C bytes in the hdr */
1909 len
= ppp
->rcomp
->decompress(ppp
->rc_state
, skb
->data
- 2,
1910 skb
->len
+ 2, ns
->data
, obuff_size
);
1912 /* Pass the compressed frame to pppd as an
1913 error indication. */
1914 if (len
== DECOMP_FATALERROR
)
1915 ppp
->rstate
|= SC_DC_FERROR
;
1923 skb_pull(skb
, 2); /* pull off the A/C bytes */
1926 /* Uncompressed frame - pass to decompressor so it
1927 can update its dictionary if necessary. */
1928 if (ppp
->rcomp
->incomp
)
1929 ppp
->rcomp
->incomp(ppp
->rc_state
, skb
->data
- 2,
1936 ppp
->rstate
|= SC_DC_ERROR
;
1937 ppp_receive_error(ppp
);
1941 #ifdef CONFIG_PPP_MULTILINK
1943 * Receive a multilink frame.
1944 * We put it on the reconstruction queue and then pull off
1945 * as many completed frames as we can.
1948 ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1952 int mphdrlen
= (ppp
->flags
& SC_MP_SHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1954 if (!pskb_may_pull(skb
, mphdrlen
+ 1) || ppp
->mrru
== 0)
1955 goto err
; /* no good, throw it away */
1957 /* Decode sequence number and begin/end bits */
1958 if (ppp
->flags
& SC_MP_SHORTSEQ
) {
1959 seq
= ((skb
->data
[2] & 0x0f) << 8) | skb
->data
[3];
1962 seq
= (skb
->data
[3] << 16) | (skb
->data
[4] << 8)| skb
->data
[5];
1965 PPP_MP_CB(skb
)->BEbits
= skb
->data
[2];
1966 skb_pull(skb
, mphdrlen
); /* pull off PPP and MP headers */
1969 * Do protocol ID decompression on the first fragment of each packet.
1971 if ((PPP_MP_CB(skb
)->BEbits
& B
) && (skb
->data
[0] & 1))
1972 *skb_push(skb
, 1) = 0;
1975 * Expand sequence number to 32 bits, making it as close
1976 * as possible to ppp->minseq.
1978 seq
|= ppp
->minseq
& ~mask
;
1979 if ((int)(ppp
->minseq
- seq
) > (int)(mask
>> 1))
1981 else if ((int)(seq
- ppp
->minseq
) > (int)(mask
>> 1))
1982 seq
-= mask
+ 1; /* should never happen */
1983 PPP_MP_CB(skb
)->sequence
= seq
;
1987 * If this packet comes before the next one we were expecting,
1990 if (seq_before(seq
, ppp
->nextseq
)) {
1992 ++ppp
->dev
->stats
.rx_dropped
;
1993 ppp_receive_error(ppp
);
1998 * Reevaluate minseq, the minimum over all channels of the
1999 * last sequence number received on each channel. Because of
2000 * the increasing sequence number rule, we know that any fragment
2001 * before `minseq' which hasn't arrived is never going to arrive.
2002 * The list of channels can't change because we have the receive
2003 * side of the ppp unit locked.
2005 list_for_each_entry(ch
, &ppp
->channels
, clist
) {
2006 if (seq_before(ch
->lastseq
, seq
))
2009 if (seq_before(ppp
->minseq
, seq
))
2012 /* Put the fragment on the reconstruction queue */
2013 ppp_mp_insert(ppp
, skb
);
2015 /* If the queue is getting long, don't wait any longer for packets
2016 before the start of the queue. */
2017 if (skb_queue_len(&ppp
->mrq
) >= PPP_MP_MAX_QLEN
) {
2018 struct sk_buff
*mskb
= skb_peek(&ppp
->mrq
);
2019 if (seq_before(ppp
->minseq
, PPP_MP_CB(mskb
)->sequence
))
2020 ppp
->minseq
= PPP_MP_CB(mskb
)->sequence
;
2023 /* Pull completed packets off the queue and receive them. */
2024 while ((skb
= ppp_mp_reconstruct(ppp
))) {
2025 if (pskb_may_pull(skb
, 2))
2026 ppp_receive_nonmp_frame(ppp
, skb
);
2028 ++ppp
->dev
->stats
.rx_length_errors
;
2030 ppp_receive_error(ppp
);
2038 ppp_receive_error(ppp
);
2042 * Insert a fragment on the MP reconstruction queue.
2043 * The queue is ordered by increasing sequence number.
2046 ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
)
2049 struct sk_buff_head
*list
= &ppp
->mrq
;
2050 u32 seq
= PPP_MP_CB(skb
)->sequence
;
2052 /* N.B. we don't need to lock the list lock because we have the
2053 ppp unit receive-side lock. */
2054 skb_queue_walk(list
, p
) {
2055 if (seq_before(seq
, PPP_MP_CB(p
)->sequence
))
2058 __skb_queue_before(list
, p
, skb
);
2062 * Reconstruct a packet from the MP fragment queue.
2063 * We go through increasing sequence numbers until we find a
2064 * complete packet, or we get to the sequence number for a fragment
2065 * which hasn't arrived but might still do so.
2067 static struct sk_buff
*
2068 ppp_mp_reconstruct(struct ppp
*ppp
)
2070 u32 seq
= ppp
->nextseq
;
2071 u32 minseq
= ppp
->minseq
;
2072 struct sk_buff_head
*list
= &ppp
->mrq
;
2073 struct sk_buff
*p
, *tmp
;
2074 struct sk_buff
*head
, *tail
;
2075 struct sk_buff
*skb
= NULL
;
2076 int lost
= 0, len
= 0;
2078 if (ppp
->mrru
== 0) /* do nothing until mrru is set */
2082 skb_queue_walk_safe(list
, p
, tmp
) {
2084 if (seq_before(PPP_MP_CB(p
)->sequence
, seq
)) {
2085 /* this can't happen, anyway ignore the skb */
2086 netdev_err(ppp
->dev
, "ppp_mp_reconstruct bad "
2088 PPP_MP_CB(p
)->sequence
, seq
);
2089 __skb_unlink(p
, list
);
2093 if (PPP_MP_CB(p
)->sequence
!= seq
) {
2095 /* Fragment `seq' is missing. If it is after
2096 minseq, it might arrive later, so stop here. */
2097 if (seq_after(seq
, minseq
))
2099 /* Fragment `seq' is lost, keep going. */
2102 seq
= seq_before(minseq
, PPP_MP_CB(p
)->sequence
)?
2103 minseq
+ 1: PPP_MP_CB(p
)->sequence
;
2106 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2107 "lost frag %u..%u\n",
2114 * At this point we know that all the fragments from
2115 * ppp->nextseq to seq are either present or lost.
2116 * Also, there are no complete packets in the queue
2117 * that have no missing fragments and end before this
2121 /* B bit set indicates this fragment starts a packet */
2122 if (PPP_MP_CB(p
)->BEbits
& B
) {
2130 /* Got a complete packet yet? */
2131 if (lost
== 0 && (PPP_MP_CB(p
)->BEbits
& E
) &&
2132 (PPP_MP_CB(head
)->BEbits
& B
)) {
2133 if (len
> ppp
->mrru
+ 2) {
2134 ++ppp
->dev
->stats
.rx_length_errors
;
2135 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2136 "PPP: reconstructed packet"
2137 " is too long (%d)\n", len
);
2142 ppp
->nextseq
= seq
+ 1;
2146 * If this is the ending fragment of a packet,
2147 * and we haven't found a complete valid packet yet,
2148 * we can discard up to and including this fragment.
2150 if (PPP_MP_CB(p
)->BEbits
& E
) {
2151 struct sk_buff
*tmp2
;
2153 skb_queue_reverse_walk_from_safe(list
, p
, tmp2
) {
2155 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2156 "discarding frag %u\n",
2157 PPP_MP_CB(p
)->sequence
);
2158 __skb_unlink(p
, list
);
2161 head
= skb_peek(list
);
2168 /* If we have a complete packet, copy it all into one skb. */
2170 /* If we have discarded any fragments,
2171 signal a receive error. */
2172 if (PPP_MP_CB(head
)->sequence
!= ppp
->nextseq
) {
2173 skb_queue_walk_safe(list
, p
, tmp
) {
2177 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2178 "discarding frag %u\n",
2179 PPP_MP_CB(p
)->sequence
);
2180 __skb_unlink(p
, list
);
2185 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2186 " missed pkts %u..%u\n",
2188 PPP_MP_CB(head
)->sequence
-1);
2189 ++ppp
->dev
->stats
.rx_dropped
;
2190 ppp_receive_error(ppp
);
2195 struct sk_buff
**fragpp
= &skb_shinfo(skb
)->frag_list
;
2196 p
= skb_queue_next(list
, head
);
2197 __skb_unlink(skb
, list
);
2198 skb_queue_walk_from_safe(list
, p
, tmp
) {
2199 __skb_unlink(p
, list
);
2205 skb
->data_len
+= p
->len
;
2206 skb
->truesize
+= p
->truesize
;
2212 __skb_unlink(skb
, list
);
2215 ppp
->nextseq
= PPP_MP_CB(tail
)->sequence
+ 1;
2220 #endif /* CONFIG_PPP_MULTILINK */
2223 * Channel interface.
2226 /* Create a new, unattached ppp channel. */
2227 int ppp_register_channel(struct ppp_channel
*chan
)
2229 return ppp_register_net_channel(current
->nsproxy
->net_ns
, chan
);
2232 /* Create a new, unattached ppp channel for specified net. */
2233 int ppp_register_net_channel(struct net
*net
, struct ppp_channel
*chan
)
2235 struct channel
*pch
;
2238 pch
= kzalloc(sizeof(struct channel
), GFP_KERNEL
);
2242 pn
= ppp_pernet(net
);
2246 pch
->chan_net
= net
;
2248 init_ppp_file(&pch
->file
, CHANNEL
);
2249 pch
->file
.hdrlen
= chan
->hdrlen
;
2250 #ifdef CONFIG_PPP_MULTILINK
2252 #endif /* CONFIG_PPP_MULTILINK */
2253 init_rwsem(&pch
->chan_sem
);
2254 spin_lock_init(&pch
->downl
);
2255 rwlock_init(&pch
->upl
);
2257 spin_lock_bh(&pn
->all_channels_lock
);
2258 pch
->file
.index
= ++pn
->last_channel_index
;
2259 list_add(&pch
->list
, &pn
->new_channels
);
2260 atomic_inc(&channel_count
);
2261 spin_unlock_bh(&pn
->all_channels_lock
);
2267 * Return the index of a channel.
2269 int ppp_channel_index(struct ppp_channel
*chan
)
2271 struct channel
*pch
= chan
->ppp
;
2274 return pch
->file
.index
;
2279 * Return the PPP unit number to which a channel is connected.
2281 int ppp_unit_number(struct ppp_channel
*chan
)
2283 struct channel
*pch
= chan
->ppp
;
2287 read_lock_bh(&pch
->upl
);
2289 unit
= pch
->ppp
->file
.index
;
2290 read_unlock_bh(&pch
->upl
);
2296 * Return the PPP device interface name of a channel.
2298 char *ppp_dev_name(struct ppp_channel
*chan
)
2300 struct channel
*pch
= chan
->ppp
;
2304 read_lock_bh(&pch
->upl
);
2305 if (pch
->ppp
&& pch
->ppp
->dev
)
2306 name
= pch
->ppp
->dev
->name
;
2307 read_unlock_bh(&pch
->upl
);
2314 * Disconnect a channel from the generic layer.
2315 * This must be called in process context.
2318 ppp_unregister_channel(struct ppp_channel
*chan
)
2320 struct channel
*pch
= chan
->ppp
;
2324 return; /* should never happen */
2329 * This ensures that we have returned from any calls into the
2330 * the channel's start_xmit or ioctl routine before we proceed.
2332 down_write(&pch
->chan_sem
);
2333 spin_lock_bh(&pch
->downl
);
2335 spin_unlock_bh(&pch
->downl
);
2336 up_write(&pch
->chan_sem
);
2337 ppp_disconnect_channel(pch
);
2339 pn
= ppp_pernet(pch
->chan_net
);
2340 spin_lock_bh(&pn
->all_channels_lock
);
2341 list_del(&pch
->list
);
2342 spin_unlock_bh(&pn
->all_channels_lock
);
2345 wake_up_interruptible(&pch
->file
.rwait
);
2346 if (atomic_dec_and_test(&pch
->file
.refcnt
))
2347 ppp_destroy_channel(pch
);
2351 * Callback from a channel when it can accept more to transmit.
2352 * This should be called at BH/softirq level, not interrupt level.
2355 ppp_output_wakeup(struct ppp_channel
*chan
)
2357 struct channel
*pch
= chan
->ppp
;
2361 ppp_channel_push(pch
);
2365 * Compression control.
2368 /* Process the PPPIOCSCOMPRESS ioctl. */
2370 ppp_set_compress(struct ppp
*ppp
, unsigned long arg
)
2373 struct compressor
*cp
, *ocomp
;
2374 struct ppp_option_data data
;
2375 void *state
, *ostate
;
2376 unsigned char ccp_option
[CCP_MAX_OPTION_LENGTH
];
2379 if (copy_from_user(&data
, (void __user
*) arg
, sizeof(data
)) ||
2380 (data
.length
<= CCP_MAX_OPTION_LENGTH
&&
2381 copy_from_user(ccp_option
, (void __user
*) data
.ptr
, data
.length
)))
2384 if (data
.length
> CCP_MAX_OPTION_LENGTH
||
2385 ccp_option
[1] < 2 || ccp_option
[1] > data
.length
)
2388 cp
= try_then_request_module(
2389 find_compressor(ccp_option
[0]),
2390 "ppp-compress-%d", ccp_option
[0]);
2395 if (data
.transmit
) {
2396 state
= cp
->comp_alloc(ccp_option
, data
.length
);
2399 ppp
->xstate
&= ~SC_COMP_RUN
;
2401 ostate
= ppp
->xc_state
;
2403 ppp
->xc_state
= state
;
2404 ppp_xmit_unlock(ppp
);
2406 ocomp
->comp_free(ostate
);
2407 module_put(ocomp
->owner
);
2411 module_put(cp
->owner
);
2414 state
= cp
->decomp_alloc(ccp_option
, data
.length
);
2417 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2419 ostate
= ppp
->rc_state
;
2421 ppp
->rc_state
= state
;
2422 ppp_recv_unlock(ppp
);
2424 ocomp
->decomp_free(ostate
);
2425 module_put(ocomp
->owner
);
2429 module_put(cp
->owner
);
2437 * Look at a CCP packet and update our state accordingly.
2438 * We assume the caller has the xmit or recv path locked.
2441 ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
)
2446 if (!pskb_may_pull(skb
, CCP_HDRLEN
+ 2))
2447 return; /* no header */
2450 switch (CCP_CODE(dp
)) {
2453 /* A ConfReq starts negotiation of compression
2454 * in one direction of transmission,
2455 * and hence brings it down...but which way?
2458 * A ConfReq indicates what the sender would like to receive
2461 /* He is proposing what I should send */
2462 ppp
->xstate
&= ~SC_COMP_RUN
;
2464 /* I am proposing to what he should send */
2465 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2472 * CCP is going down, both directions of transmission
2474 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2475 ppp
->xstate
&= ~SC_COMP_RUN
;
2479 if ((ppp
->flags
& (SC_CCP_OPEN
| SC_CCP_UP
)) != SC_CCP_OPEN
)
2481 len
= CCP_LENGTH(dp
);
2482 if (!pskb_may_pull(skb
, len
+ 2))
2483 return; /* too short */
2486 if (len
< CCP_OPT_MINLEN
|| len
< CCP_OPT_LENGTH(dp
))
2489 /* we will start receiving compressed packets */
2492 if (ppp
->rcomp
->decomp_init(ppp
->rc_state
, dp
, len
,
2493 ppp
->file
.index
, 0, ppp
->mru
, ppp
->debug
)) {
2494 ppp
->rstate
|= SC_DECOMP_RUN
;
2495 ppp
->rstate
&= ~(SC_DC_ERROR
| SC_DC_FERROR
);
2498 /* we will soon start sending compressed packets */
2501 if (ppp
->xcomp
->comp_init(ppp
->xc_state
, dp
, len
,
2502 ppp
->file
.index
, 0, ppp
->debug
))
2503 ppp
->xstate
|= SC_COMP_RUN
;
2508 /* reset the [de]compressor */
2509 if ((ppp
->flags
& SC_CCP_UP
) == 0)
2512 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
)) {
2513 ppp
->rcomp
->decomp_reset(ppp
->rc_state
);
2514 ppp
->rstate
&= ~SC_DC_ERROR
;
2517 if (ppp
->xc_state
&& (ppp
->xstate
& SC_COMP_RUN
))
2518 ppp
->xcomp
->comp_reset(ppp
->xc_state
);
2524 /* Free up compression resources. */
2526 ppp_ccp_closed(struct ppp
*ppp
)
2528 void *xstate
, *rstate
;
2529 struct compressor
*xcomp
, *rcomp
;
2532 ppp
->flags
&= ~(SC_CCP_OPEN
| SC_CCP_UP
);
2535 xstate
= ppp
->xc_state
;
2536 ppp
->xc_state
= NULL
;
2539 rstate
= ppp
->rc_state
;
2540 ppp
->rc_state
= NULL
;
2544 xcomp
->comp_free(xstate
);
2545 module_put(xcomp
->owner
);
2548 rcomp
->decomp_free(rstate
);
2549 module_put(rcomp
->owner
);
2553 /* List of compressors. */
2554 static LIST_HEAD(compressor_list
);
2555 static DEFINE_SPINLOCK(compressor_list_lock
);
2557 struct compressor_entry
{
2558 struct list_head list
;
2559 struct compressor
*comp
;
2562 static struct compressor_entry
*
2563 find_comp_entry(int proto
)
2565 struct compressor_entry
*ce
;
2567 list_for_each_entry(ce
, &compressor_list
, list
) {
2568 if (ce
->comp
->compress_proto
== proto
)
2574 /* Register a compressor */
2576 ppp_register_compressor(struct compressor
*cp
)
2578 struct compressor_entry
*ce
;
2580 spin_lock(&compressor_list_lock
);
2582 if (find_comp_entry(cp
->compress_proto
))
2585 ce
= kmalloc(sizeof(struct compressor_entry
), GFP_ATOMIC
);
2590 list_add(&ce
->list
, &compressor_list
);
2592 spin_unlock(&compressor_list_lock
);
2596 /* Unregister a compressor */
2598 ppp_unregister_compressor(struct compressor
*cp
)
2600 struct compressor_entry
*ce
;
2602 spin_lock(&compressor_list_lock
);
2603 ce
= find_comp_entry(cp
->compress_proto
);
2604 if (ce
&& ce
->comp
== cp
) {
2605 list_del(&ce
->list
);
2608 spin_unlock(&compressor_list_lock
);
2611 /* Find a compressor. */
2612 static struct compressor
*
2613 find_compressor(int type
)
2615 struct compressor_entry
*ce
;
2616 struct compressor
*cp
= NULL
;
2618 spin_lock(&compressor_list_lock
);
2619 ce
= find_comp_entry(type
);
2622 if (!try_module_get(cp
->owner
))
2625 spin_unlock(&compressor_list_lock
);
2630 * Miscelleneous stuff.
2634 ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
)
2636 struct slcompress
*vj
= ppp
->vj
;
2638 memset(st
, 0, sizeof(*st
));
2639 st
->p
.ppp_ipackets
= ppp
->stats64
.rx_packets
;
2640 st
->p
.ppp_ierrors
= ppp
->dev
->stats
.rx_errors
;
2641 st
->p
.ppp_ibytes
= ppp
->stats64
.rx_bytes
;
2642 st
->p
.ppp_opackets
= ppp
->stats64
.tx_packets
;
2643 st
->p
.ppp_oerrors
= ppp
->dev
->stats
.tx_errors
;
2644 st
->p
.ppp_obytes
= ppp
->stats64
.tx_bytes
;
2647 st
->vj
.vjs_packets
= vj
->sls_o_compressed
+ vj
->sls_o_uncompressed
;
2648 st
->vj
.vjs_compressed
= vj
->sls_o_compressed
;
2649 st
->vj
.vjs_searches
= vj
->sls_o_searches
;
2650 st
->vj
.vjs_misses
= vj
->sls_o_misses
;
2651 st
->vj
.vjs_errorin
= vj
->sls_i_error
;
2652 st
->vj
.vjs_tossed
= vj
->sls_i_tossed
;
2653 st
->vj
.vjs_uncompressedin
= vj
->sls_i_uncompressed
;
2654 st
->vj
.vjs_compressedin
= vj
->sls_i_compressed
;
2658 * Stuff for handling the lists of ppp units and channels
2659 * and for initialization.
2663 * Create a new ppp interface unit. Fails if it can't allocate memory
2664 * or if there is already a unit with the requested number.
2665 * unit == -1 means allocate a new number.
2668 ppp_create_interface(struct net
*net
, int unit
, int *retp
)
2672 struct net_device
*dev
= NULL
;
2676 dev
= alloc_netdev(sizeof(struct ppp
), "", NET_NAME_UNKNOWN
,
2681 pn
= ppp_pernet(net
);
2683 ppp
= netdev_priv(dev
);
2686 init_ppp_file(&ppp
->file
, INTERFACE
);
2687 ppp
->file
.hdrlen
= PPP_HDRLEN
- 2; /* don't count proto bytes */
2688 for (i
= 0; i
< NUM_NP
; ++i
)
2689 ppp
->npmode
[i
] = NPMODE_PASS
;
2690 INIT_LIST_HEAD(&ppp
->channels
);
2691 spin_lock_init(&ppp
->rlock
);
2692 spin_lock_init(&ppp
->wlock
);
2693 #ifdef CONFIG_PPP_MULTILINK
2695 skb_queue_head_init(&ppp
->mrq
);
2696 #endif /* CONFIG_PPP_MULTILINK */
2697 #ifdef CONFIG_PPP_FILTER
2698 ppp
->pass_filter
= NULL
;
2699 ppp
->active_filter
= NULL
;
2700 #endif /* CONFIG_PPP_FILTER */
2703 * drum roll: don't forget to set
2704 * the net device is belong to
2706 dev_net_set(dev
, net
);
2708 mutex_lock(&pn
->all_ppp_mutex
);
2711 unit
= unit_get(&pn
->units_idr
, ppp
);
2718 if (unit_find(&pn
->units_idr
, unit
))
2719 goto out2
; /* unit already exists */
2721 * if caller need a specified unit number
2722 * lets try to satisfy him, otherwise --
2723 * he should better ask us for new unit number
2725 * NOTE: yes I know that returning EEXIST it's not
2726 * fair but at least pppd will ask us to allocate
2727 * new unit in this case so user is happy :)
2729 unit
= unit_set(&pn
->units_idr
, ppp
, unit
);
2734 /* Initialize the new ppp unit */
2735 ppp
->file
.index
= unit
;
2736 sprintf(dev
->name
, "ppp%d", unit
);
2738 ret
= register_netdev(dev
);
2740 unit_put(&pn
->units_idr
, unit
);
2741 netdev_err(ppp
->dev
, "PPP: couldn't register device %s (%d)\n",
2748 atomic_inc(&ppp_unit_count
);
2749 mutex_unlock(&pn
->all_ppp_mutex
);
2755 mutex_unlock(&pn
->all_ppp_mutex
);
2763 * Initialize a ppp_file structure.
2766 init_ppp_file(struct ppp_file
*pf
, int kind
)
2769 skb_queue_head_init(&pf
->xq
);
2770 skb_queue_head_init(&pf
->rq
);
2771 atomic_set(&pf
->refcnt
, 1);
2772 init_waitqueue_head(&pf
->rwait
);
2776 * Take down a ppp interface unit - called when the owning file
2777 * (the one that created the unit) is closed or detached.
2779 static void ppp_shutdown_interface(struct ppp
*ppp
)
2783 pn
= ppp_pernet(ppp
->ppp_net
);
2784 mutex_lock(&pn
->all_ppp_mutex
);
2786 /* This will call dev_close() for us. */
2788 if (!ppp
->closing
) {
2791 unregister_netdev(ppp
->dev
);
2792 unit_put(&pn
->units_idr
, ppp
->file
.index
);
2798 wake_up_interruptible(&ppp
->file
.rwait
);
2800 mutex_unlock(&pn
->all_ppp_mutex
);
2804 * Free the memory used by a ppp unit. This is only called once
2805 * there are no channels connected to the unit and no file structs
2806 * that reference the unit.
2808 static void ppp_destroy_interface(struct ppp
*ppp
)
2810 atomic_dec(&ppp_unit_count
);
2812 if (!ppp
->file
.dead
|| ppp
->n_channels
) {
2813 /* "can't happen" */
2814 netdev_err(ppp
->dev
, "ppp: destroying ppp struct %p "
2815 "but dead=%d n_channels=%d !\n",
2816 ppp
, ppp
->file
.dead
, ppp
->n_channels
);
2820 ppp_ccp_closed(ppp
);
2825 skb_queue_purge(&ppp
->file
.xq
);
2826 skb_queue_purge(&ppp
->file
.rq
);
2827 #ifdef CONFIG_PPP_MULTILINK
2828 skb_queue_purge(&ppp
->mrq
);
2829 #endif /* CONFIG_PPP_MULTILINK */
2830 #ifdef CONFIG_PPP_FILTER
2831 if (ppp
->pass_filter
) {
2832 bpf_prog_destroy(ppp
->pass_filter
);
2833 ppp
->pass_filter
= NULL
;
2836 if (ppp
->active_filter
) {
2837 bpf_prog_destroy(ppp
->active_filter
);
2838 ppp
->active_filter
= NULL
;
2840 #endif /* CONFIG_PPP_FILTER */
2842 kfree_skb(ppp
->xmit_pending
);
2844 free_netdev(ppp
->dev
);
2848 * Locate an existing ppp unit.
2849 * The caller should have locked the all_ppp_mutex.
2852 ppp_find_unit(struct ppp_net
*pn
, int unit
)
2854 return unit_find(&pn
->units_idr
, unit
);
2858 * Locate an existing ppp channel.
2859 * The caller should have locked the all_channels_lock.
2860 * First we look in the new_channels list, then in the
2861 * all_channels list. If found in the new_channels list,
2862 * we move it to the all_channels list. This is for speed
2863 * when we have a lot of channels in use.
2865 static struct channel
*
2866 ppp_find_channel(struct ppp_net
*pn
, int unit
)
2868 struct channel
*pch
;
2870 list_for_each_entry(pch
, &pn
->new_channels
, list
) {
2871 if (pch
->file
.index
== unit
) {
2872 list_move(&pch
->list
, &pn
->all_channels
);
2877 list_for_each_entry(pch
, &pn
->all_channels
, list
) {
2878 if (pch
->file
.index
== unit
)
2886 * Connect a PPP channel to a PPP interface unit.
2889 ppp_connect_channel(struct channel
*pch
, int unit
)
2896 pn
= ppp_pernet(pch
->chan_net
);
2898 mutex_lock(&pn
->all_ppp_mutex
);
2899 ppp
= ppp_find_unit(pn
, unit
);
2902 write_lock_bh(&pch
->upl
);
2908 if (pch
->file
.hdrlen
> ppp
->file
.hdrlen
)
2909 ppp
->file
.hdrlen
= pch
->file
.hdrlen
;
2910 hdrlen
= pch
->file
.hdrlen
+ 2; /* for protocol bytes */
2911 if (hdrlen
> ppp
->dev
->hard_header_len
)
2912 ppp
->dev
->hard_header_len
= hdrlen
;
2913 list_add_tail(&pch
->clist
, &ppp
->channels
);
2916 atomic_inc(&ppp
->file
.refcnt
);
2921 write_unlock_bh(&pch
->upl
);
2923 mutex_unlock(&pn
->all_ppp_mutex
);
2928 * Disconnect a channel from its ppp unit.
2931 ppp_disconnect_channel(struct channel
*pch
)
2936 write_lock_bh(&pch
->upl
);
2939 write_unlock_bh(&pch
->upl
);
2941 /* remove it from the ppp unit's list */
2943 list_del(&pch
->clist
);
2944 if (--ppp
->n_channels
== 0)
2945 wake_up_interruptible(&ppp
->file
.rwait
);
2947 if (atomic_dec_and_test(&ppp
->file
.refcnt
))
2948 ppp_destroy_interface(ppp
);
2955 * Free up the resources used by a ppp channel.
2957 static void ppp_destroy_channel(struct channel
*pch
)
2959 atomic_dec(&channel_count
);
2961 if (!pch
->file
.dead
) {
2962 /* "can't happen" */
2963 pr_err("ppp: destroying undead channel %p !\n", pch
);
2966 skb_queue_purge(&pch
->file
.xq
);
2967 skb_queue_purge(&pch
->file
.rq
);
2971 static void __exit
ppp_cleanup(void)
2973 /* should never happen */
2974 if (atomic_read(&ppp_unit_count
) || atomic_read(&channel_count
))
2975 pr_err("PPP: removing module but units remain!\n");
2976 unregister_chrdev(PPP_MAJOR
, "ppp");
2977 device_destroy(ppp_class
, MKDEV(PPP_MAJOR
, 0));
2978 class_destroy(ppp_class
);
2979 unregister_pernet_device(&ppp_net_ops
);
2983 * Units handling. Caller must protect concurrent access
2984 * by holding all_ppp_mutex
2987 /* associate pointer with specified number */
2988 static int unit_set(struct idr
*p
, void *ptr
, int n
)
2992 unit
= idr_alloc(p
, ptr
, n
, n
+ 1, GFP_KERNEL
);
2993 if (unit
== -ENOSPC
)
2998 /* get new free unit number and associate pointer with it */
2999 static int unit_get(struct idr
*p
, void *ptr
)
3001 return idr_alloc(p
, ptr
, 0, 0, GFP_KERNEL
);
3004 /* put unit number back to a pool */
3005 static void unit_put(struct idr
*p
, int n
)
3010 /* get pointer associated with the number */
3011 static void *unit_find(struct idr
*p
, int n
)
3013 return idr_find(p
, n
);
3016 /* Module/initialization stuff */
3018 module_init(ppp_init
);
3019 module_exit(ppp_cleanup
);
3021 EXPORT_SYMBOL(ppp_register_net_channel
);
3022 EXPORT_SYMBOL(ppp_register_channel
);
3023 EXPORT_SYMBOL(ppp_unregister_channel
);
3024 EXPORT_SYMBOL(ppp_channel_index
);
3025 EXPORT_SYMBOL(ppp_unit_number
);
3026 EXPORT_SYMBOL(ppp_dev_name
);
3027 EXPORT_SYMBOL(ppp_input
);
3028 EXPORT_SYMBOL(ppp_input_error
);
3029 EXPORT_SYMBOL(ppp_output_wakeup
);
3030 EXPORT_SYMBOL(ppp_register_compressor
);
3031 EXPORT_SYMBOL(ppp_unregister_compressor
);
3032 MODULE_LICENSE("GPL");
3033 MODULE_ALIAS_CHARDEV(PPP_MAJOR
, 0);
3034 MODULE_ALIAS("devname:ppp");