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/sched/signal.h>
28 #include <linux/kmod.h>
29 #include <linux/init.h>
30 #include <linux/list.h>
31 #include <linux/idr.h>
32 #include <linux/netdevice.h>
33 #include <linux/poll.h>
34 #include <linux/ppp_defs.h>
35 #include <linux/filter.h>
36 #include <linux/ppp-ioctl.h>
37 #include <linux/ppp_channel.h>
38 #include <linux/ppp-comp.h>
39 #include <linux/skbuff.h>
40 #include <linux/rtnetlink.h>
41 #include <linux/if_arp.h>
43 #include <linux/tcp.h>
44 #include <linux/spinlock.h>
45 #include <linux/rwsem.h>
46 #include <linux/stddef.h>
47 #include <linux/device.h>
48 #include <linux/mutex.h>
49 #include <linux/slab.h>
50 #include <linux/file.h>
51 #include <asm/unaligned.h>
52 #include <net/slhc_vj.h>
53 #include <linux/atomic.h>
54 #include <linux/refcount.h>
56 #include <linux/nsproxy.h>
57 #include <net/net_namespace.h>
58 #include <net/netns/generic.h>
60 #define PPP_VERSION "2.4.2"
63 * Network protocols we support.
65 #define NP_IP 0 /* Internet Protocol V4 */
66 #define NP_IPV6 1 /* Internet Protocol V6 */
67 #define NP_IPX 2 /* IPX protocol */
68 #define NP_AT 3 /* Appletalk protocol */
69 #define NP_MPLS_UC 4 /* MPLS unicast */
70 #define NP_MPLS_MC 5 /* MPLS multicast */
71 #define NUM_NP 6 /* Number of NPs. */
73 #define MPHDRLEN 6 /* multilink protocol header length */
74 #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */
77 * An instance of /dev/ppp can be associated with either a ppp
78 * interface unit or a ppp channel. In both cases, file->private_data
79 * points to one of these.
85 struct sk_buff_head xq
; /* pppd transmit queue */
86 struct sk_buff_head rq
; /* receive queue for pppd */
87 wait_queue_head_t rwait
; /* for poll on reading /dev/ppp */
88 refcount_t refcnt
; /* # refs (incl /dev/ppp attached) */
89 int hdrlen
; /* space to leave for headers */
90 int index
; /* interface unit / channel number */
91 int dead
; /* unit/channel has been shut down */
94 #define PF_TO_X(pf, X) container_of(pf, X, file)
96 #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp)
97 #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel)
100 * Data structure to hold primary network stats for which
101 * we want to use 64 bit storage. Other network stats
102 * are stored in dev->stats of the ppp strucute.
104 struct ppp_link_stats
{
112 * Data structure describing one ppp unit.
113 * A ppp unit corresponds to a ppp network interface device
114 * and represents a multilink bundle.
115 * It can have 0 or more ppp channels connected to it.
118 struct ppp_file file
; /* stuff for read/write/poll 0 */
119 struct file
*owner
; /* file that owns this unit 48 */
120 struct list_head channels
; /* list of attached channels 4c */
121 int n_channels
; /* how many channels are attached 54 */
122 spinlock_t rlock
; /* lock for receive side 58 */
123 spinlock_t wlock
; /* lock for transmit side 5c */
124 int __percpu
*xmit_recursion
; /* xmit recursion detect */
125 int mru
; /* max receive unit 60 */
126 unsigned int flags
; /* control bits 64 */
127 unsigned int xstate
; /* transmit state bits 68 */
128 unsigned int rstate
; /* receive state bits 6c */
129 int debug
; /* debug flags 70 */
130 struct slcompress
*vj
; /* state for VJ header compression */
131 enum NPmode npmode
[NUM_NP
]; /* what to do with each net proto 78 */
132 struct sk_buff
*xmit_pending
; /* a packet ready to go out 88 */
133 struct compressor
*xcomp
; /* transmit packet compressor 8c */
134 void *xc_state
; /* its internal state 90 */
135 struct compressor
*rcomp
; /* receive decompressor 94 */
136 void *rc_state
; /* its internal state 98 */
137 unsigned long last_xmit
; /* jiffies when last pkt sent 9c */
138 unsigned long last_recv
; /* jiffies when last pkt rcvd a0 */
139 struct net_device
*dev
; /* network interface device a4 */
140 int closing
; /* is device closing down? a8 */
141 #ifdef CONFIG_PPP_MULTILINK
142 int nxchan
; /* next channel to send something on */
143 u32 nxseq
; /* next sequence number to send */
144 int mrru
; /* MP: max reconst. receive unit */
145 u32 nextseq
; /* MP: seq no of next packet */
146 u32 minseq
; /* MP: min of most recent seqnos */
147 struct sk_buff_head mrq
; /* MP: receive reconstruction queue */
148 #endif /* CONFIG_PPP_MULTILINK */
149 #ifdef CONFIG_PPP_FILTER
150 struct bpf_prog
*pass_filter
; /* filter for packets to pass */
151 struct bpf_prog
*active_filter
; /* filter for pkts to reset idle */
152 #endif /* CONFIG_PPP_FILTER */
153 struct net
*ppp_net
; /* the net we belong to */
154 struct ppp_link_stats stats64
; /* 64 bit network stats */
158 * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
159 * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP,
161 * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR.
162 * Bits in xstate: SC_COMP_RUN
164 #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \
165 |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \
166 |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP)
169 * Private data structure for each channel.
170 * This includes the data structure used for multilink.
173 struct ppp_file file
; /* stuff for read/write/poll */
174 struct list_head list
; /* link in all/new_channels list */
175 struct ppp_channel
*chan
; /* public channel data structure */
176 struct rw_semaphore chan_sem
; /* protects `chan' during chan ioctl */
177 spinlock_t downl
; /* protects `chan', file.xq dequeue */
178 struct ppp
*ppp
; /* ppp unit we're connected to */
179 struct net
*chan_net
; /* the net channel belongs to */
180 struct list_head clist
; /* link in list of channels per unit */
181 rwlock_t upl
; /* protects `ppp' */
182 #ifdef CONFIG_PPP_MULTILINK
183 u8 avail
; /* flag used in multilink stuff */
184 u8 had_frag
; /* >= 1 fragments have been sent */
185 u32 lastseq
; /* MP: last sequence # received */
186 int speed
; /* speed of the corresponding ppp channel*/
187 #endif /* CONFIG_PPP_MULTILINK */
197 * SMP locking issues:
198 * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels
199 * list and the ppp.n_channels field, you need to take both locks
200 * before you modify them.
201 * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
205 static DEFINE_MUTEX(ppp_mutex
);
206 static atomic_t ppp_unit_count
= ATOMIC_INIT(0);
207 static atomic_t channel_count
= ATOMIC_INIT(0);
209 /* per-net private data for this module */
210 static unsigned int ppp_net_id __read_mostly
;
212 /* units to ppp mapping */
213 struct idr units_idr
;
216 * all_ppp_mutex protects the units_idr mapping.
217 * It also ensures that finding a ppp unit in the units_idr
218 * map and updating its file.refcnt field is atomic.
220 struct mutex all_ppp_mutex
;
223 struct list_head all_channels
;
224 struct list_head new_channels
;
225 int last_channel_index
;
228 * all_channels_lock protects all_channels and
229 * last_channel_index, and the atomicity of find
230 * a channel and updating its file.refcnt field.
232 spinlock_t all_channels_lock
;
235 /* Get the PPP protocol number from a skb */
236 #define PPP_PROTO(skb) get_unaligned_be16((skb)->data)
238 /* We limit the length of ppp->file.rq to this (arbitrary) value */
239 #define PPP_MAX_RQLEN 32
242 * Maximum number of multilink fragments queued up.
243 * This has to be large enough to cope with the maximum latency of
244 * the slowest channel relative to the others. Strictly it should
245 * depend on the number of channels and their characteristics.
247 #define PPP_MP_MAX_QLEN 128
249 /* Multilink header bits. */
250 #define B 0x80 /* this fragment begins a packet */
251 #define E 0x40 /* this fragment ends a packet */
253 /* Compare multilink sequence numbers (assumed to be 32 bits wide) */
254 #define seq_before(a, b) ((s32)((a) - (b)) < 0)
255 #define seq_after(a, b) ((s32)((a) - (b)) > 0)
258 static int ppp_unattached_ioctl(struct net
*net
, struct ppp_file
*pf
,
259 struct file
*file
, unsigned int cmd
, unsigned long arg
);
260 static void ppp_xmit_process(struct ppp
*ppp
);
261 static void ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
);
262 static void ppp_push(struct ppp
*ppp
);
263 static void ppp_channel_push(struct channel
*pch
);
264 static void ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
,
265 struct channel
*pch
);
266 static void ppp_receive_error(struct ppp
*ppp
);
267 static void ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
);
268 static struct sk_buff
*ppp_decompress_frame(struct ppp
*ppp
,
269 struct sk_buff
*skb
);
270 #ifdef CONFIG_PPP_MULTILINK
271 static void ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
,
272 struct channel
*pch
);
273 static void ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
);
274 static struct sk_buff
*ppp_mp_reconstruct(struct ppp
*ppp
);
275 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
);
276 #endif /* CONFIG_PPP_MULTILINK */
277 static int ppp_set_compress(struct ppp
*ppp
, unsigned long arg
);
278 static void ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
);
279 static void ppp_ccp_closed(struct ppp
*ppp
);
280 static struct compressor
*find_compressor(int type
);
281 static void ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
);
282 static int ppp_create_interface(struct net
*net
, struct file
*file
, int *unit
);
283 static void init_ppp_file(struct ppp_file
*pf
, int kind
);
284 static void ppp_destroy_interface(struct ppp
*ppp
);
285 static struct ppp
*ppp_find_unit(struct ppp_net
*pn
, int unit
);
286 static struct channel
*ppp_find_channel(struct ppp_net
*pn
, int unit
);
287 static int ppp_connect_channel(struct channel
*pch
, int unit
);
288 static int ppp_disconnect_channel(struct channel
*pch
);
289 static void ppp_destroy_channel(struct channel
*pch
);
290 static int unit_get(struct idr
*p
, void *ptr
);
291 static int unit_set(struct idr
*p
, void *ptr
, int n
);
292 static void unit_put(struct idr
*p
, int n
);
293 static void *unit_find(struct idr
*p
, int n
);
294 static void ppp_setup(struct net_device
*dev
);
296 static const struct net_device_ops ppp_netdev_ops
;
298 static struct class *ppp_class
;
300 /* per net-namespace data */
301 static inline struct ppp_net
*ppp_pernet(struct net
*net
)
305 return net_generic(net
, ppp_net_id
);
308 /* Translates a PPP protocol number to a NP index (NP == network protocol) */
309 static inline int proto_to_npindex(int proto
)
328 /* Translates an NP index into a PPP protocol number */
329 static const int npindex_to_proto
[NUM_NP
] = {
338 /* Translates an ethertype into an NP index */
339 static inline int ethertype_to_npindex(int ethertype
)
359 /* Translates an NP index into an ethertype */
360 static const int npindex_to_ethertype
[NUM_NP
] = {
372 #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock)
373 #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock)
374 #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock)
375 #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock)
376 #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \
377 ppp_recv_lock(ppp); } while (0)
378 #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \
379 ppp_xmit_unlock(ppp); } while (0)
382 * /dev/ppp device routines.
383 * The /dev/ppp device is used by pppd to control the ppp unit.
384 * It supports the read, write, ioctl and poll functions.
385 * Open instances of /dev/ppp can be in one of three states:
386 * unattached, attached to a ppp unit, or attached to a ppp channel.
388 static int ppp_open(struct inode
*inode
, struct file
*file
)
391 * This could (should?) be enforced by the permissions on /dev/ppp.
393 if (!ns_capable(file
->f_cred
->user_ns
, CAP_NET_ADMIN
))
398 static int ppp_release(struct inode
*unused
, struct file
*file
)
400 struct ppp_file
*pf
= file
->private_data
;
404 file
->private_data
= NULL
;
405 if (pf
->kind
== INTERFACE
) {
408 if (file
== ppp
->owner
)
409 unregister_netdevice(ppp
->dev
);
412 if (refcount_dec_and_test(&pf
->refcnt
)) {
415 ppp_destroy_interface(PF_TO_PPP(pf
));
418 ppp_destroy_channel(PF_TO_CHANNEL(pf
));
426 static ssize_t
ppp_read(struct file
*file
, char __user
*buf
,
427 size_t count
, loff_t
*ppos
)
429 struct ppp_file
*pf
= file
->private_data
;
430 DECLARE_WAITQUEUE(wait
, current
);
432 struct sk_buff
*skb
= NULL
;
440 add_wait_queue(&pf
->rwait
, &wait
);
442 set_current_state(TASK_INTERRUPTIBLE
);
443 skb
= skb_dequeue(&pf
->rq
);
449 if (pf
->kind
== INTERFACE
) {
451 * Return 0 (EOF) on an interface that has no
452 * channels connected, unless it is looping
453 * network traffic (demand mode).
455 struct ppp
*ppp
= PF_TO_PPP(pf
);
458 if (ppp
->n_channels
== 0 &&
459 (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0) {
460 ppp_recv_unlock(ppp
);
463 ppp_recv_unlock(ppp
);
466 if (file
->f_flags
& O_NONBLOCK
)
469 if (signal_pending(current
))
473 set_current_state(TASK_RUNNING
);
474 remove_wait_queue(&pf
->rwait
, &wait
);
480 if (skb
->len
> count
)
485 iov_iter_init(&to
, READ
, &iov
, 1, count
);
486 if (skb_copy_datagram_iter(skb
, 0, &to
, skb
->len
))
496 static ssize_t
ppp_write(struct file
*file
, const char __user
*buf
,
497 size_t count
, loff_t
*ppos
)
499 struct ppp_file
*pf
= file
->private_data
;
506 skb
= alloc_skb(count
+ pf
->hdrlen
, GFP_KERNEL
);
509 skb_reserve(skb
, pf
->hdrlen
);
511 if (copy_from_user(skb_put(skb
, count
), buf
, count
)) {
516 skb_queue_tail(&pf
->xq
, skb
);
520 ppp_xmit_process(PF_TO_PPP(pf
));
523 ppp_channel_push(PF_TO_CHANNEL(pf
));
533 /* No kernel lock - fine */
534 static unsigned int ppp_poll(struct file
*file
, poll_table
*wait
)
536 struct ppp_file
*pf
= file
->private_data
;
541 poll_wait(file
, &pf
->rwait
, wait
);
542 mask
= POLLOUT
| POLLWRNORM
;
543 if (skb_peek(&pf
->rq
))
544 mask
|= POLLIN
| POLLRDNORM
;
547 else if (pf
->kind
== INTERFACE
) {
548 /* see comment in ppp_read */
549 struct ppp
*ppp
= PF_TO_PPP(pf
);
552 if (ppp
->n_channels
== 0 &&
553 (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0)
554 mask
|= POLLIN
| POLLRDNORM
;
555 ppp_recv_unlock(ppp
);
561 #ifdef CONFIG_PPP_FILTER
562 static int get_filter(void __user
*arg
, struct sock_filter
**p
)
564 struct sock_fprog uprog
;
565 struct sock_filter
*code
= NULL
;
568 if (copy_from_user(&uprog
, arg
, sizeof(uprog
)))
576 len
= uprog
.len
* sizeof(struct sock_filter
);
577 code
= memdup_user(uprog
.filter
, len
);
579 return PTR_ERR(code
);
584 #endif /* CONFIG_PPP_FILTER */
586 static long ppp_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
590 int err
= -EFAULT
, val
, val2
, i
;
591 struct ppp_idle idle
;
594 struct slcompress
*vj
;
595 void __user
*argp
= (void __user
*)arg
;
596 int __user
*p
= argp
;
598 mutex_lock(&ppp_mutex
);
600 pf
= file
->private_data
;
602 err
= ppp_unattached_ioctl(current
->nsproxy
->net_ns
,
607 if (cmd
== PPPIOCDETACH
) {
609 * We have to be careful here... if the file descriptor
610 * has been dup'd, we could have another process in the
611 * middle of a poll using the same file *, so we had
612 * better not free the interface data structures -
613 * instead we fail the ioctl. Even in this case, we
614 * shut down the interface if we are the owner of it.
615 * Actually, we should get rid of PPPIOCDETACH, userland
616 * (i.e. pppd) could achieve the same effect by closing
617 * this fd and reopening /dev/ppp.
620 if (pf
->kind
== INTERFACE
) {
623 if (file
== ppp
->owner
)
624 unregister_netdevice(ppp
->dev
);
627 if (atomic_long_read(&file
->f_count
) < 2) {
628 ppp_release(NULL
, file
);
631 pr_warn("PPPIOCDETACH file->f_count=%ld\n",
632 atomic_long_read(&file
->f_count
));
636 if (pf
->kind
== CHANNEL
) {
638 struct ppp_channel
*chan
;
640 pch
= PF_TO_CHANNEL(pf
);
644 if (get_user(unit
, p
))
646 err
= ppp_connect_channel(pch
, unit
);
650 err
= ppp_disconnect_channel(pch
);
654 down_read(&pch
->chan_sem
);
657 if (chan
&& chan
->ops
->ioctl
)
658 err
= chan
->ops
->ioctl(chan
, cmd
, arg
);
659 up_read(&pch
->chan_sem
);
664 if (pf
->kind
!= INTERFACE
) {
666 pr_err("PPP: not interface or channel??\n");
674 if (get_user(val
, p
))
681 if (get_user(val
, p
))
684 cflags
= ppp
->flags
& ~val
;
685 #ifdef CONFIG_PPP_MULTILINK
686 if (!(ppp
->flags
& SC_MULTILINK
) && (val
& SC_MULTILINK
))
689 ppp
->flags
= val
& SC_FLAG_BITS
;
691 if (cflags
& SC_CCP_OPEN
)
697 val
= ppp
->flags
| ppp
->xstate
| ppp
->rstate
;
698 if (put_user(val
, p
))
703 case PPPIOCSCOMPRESS
:
704 err
= ppp_set_compress(ppp
, arg
);
708 if (put_user(ppp
->file
.index
, p
))
714 if (get_user(val
, p
))
721 if (put_user(ppp
->debug
, p
))
727 idle
.xmit_idle
= (jiffies
- ppp
->last_xmit
) / HZ
;
728 idle
.recv_idle
= (jiffies
- ppp
->last_recv
) / HZ
;
729 if (copy_to_user(argp
, &idle
, sizeof(idle
)))
735 if (get_user(val
, p
))
738 if ((val
>> 16) != 0) {
742 vj
= slhc_init(val2
+1, val
+1);
757 if (copy_from_user(&npi
, argp
, sizeof(npi
)))
759 err
= proto_to_npindex(npi
.protocol
);
763 if (cmd
== PPPIOCGNPMODE
) {
765 npi
.mode
= ppp
->npmode
[i
];
766 if (copy_to_user(argp
, &npi
, sizeof(npi
)))
769 ppp
->npmode
[i
] = npi
.mode
;
770 /* we may be able to transmit more packets now (??) */
771 netif_wake_queue(ppp
->dev
);
776 #ifdef CONFIG_PPP_FILTER
779 struct sock_filter
*code
;
781 err
= get_filter(argp
, &code
);
783 struct bpf_prog
*pass_filter
= NULL
;
784 struct sock_fprog_kern fprog
= {
791 err
= bpf_prog_create(&pass_filter
, &fprog
);
794 if (ppp
->pass_filter
)
795 bpf_prog_destroy(ppp
->pass_filter
);
796 ppp
->pass_filter
= pass_filter
;
805 struct sock_filter
*code
;
807 err
= get_filter(argp
, &code
);
809 struct bpf_prog
*active_filter
= NULL
;
810 struct sock_fprog_kern fprog
= {
817 err
= bpf_prog_create(&active_filter
, &fprog
);
820 if (ppp
->active_filter
)
821 bpf_prog_destroy(ppp
->active_filter
);
822 ppp
->active_filter
= active_filter
;
829 #endif /* CONFIG_PPP_FILTER */
831 #ifdef CONFIG_PPP_MULTILINK
833 if (get_user(val
, p
))
837 ppp_recv_unlock(ppp
);
840 #endif /* CONFIG_PPP_MULTILINK */
847 mutex_unlock(&ppp_mutex
);
852 static int ppp_unattached_ioctl(struct net
*net
, struct ppp_file
*pf
,
853 struct file
*file
, unsigned int cmd
, unsigned long arg
)
855 int unit
, err
= -EFAULT
;
857 struct channel
*chan
;
859 int __user
*p
= (int __user
*)arg
;
863 /* Create a new ppp unit */
864 if (get_user(unit
, p
))
866 err
= ppp_create_interface(net
, file
, &unit
);
871 if (put_user(unit
, p
))
877 /* Attach to an existing ppp unit */
878 if (get_user(unit
, p
))
881 pn
= ppp_pernet(net
);
882 mutex_lock(&pn
->all_ppp_mutex
);
883 ppp
= ppp_find_unit(pn
, unit
);
885 refcount_inc(&ppp
->file
.refcnt
);
886 file
->private_data
= &ppp
->file
;
889 mutex_unlock(&pn
->all_ppp_mutex
);
893 if (get_user(unit
, p
))
896 pn
= ppp_pernet(net
);
897 spin_lock_bh(&pn
->all_channels_lock
);
898 chan
= ppp_find_channel(pn
, unit
);
900 refcount_inc(&chan
->file
.refcnt
);
901 file
->private_data
= &chan
->file
;
904 spin_unlock_bh(&pn
->all_channels_lock
);
914 static const struct file_operations ppp_device_fops
= {
915 .owner
= THIS_MODULE
,
919 .unlocked_ioctl
= ppp_ioctl
,
921 .release
= ppp_release
,
922 .llseek
= noop_llseek
,
925 static __net_init
int ppp_init_net(struct net
*net
)
927 struct ppp_net
*pn
= net_generic(net
, ppp_net_id
);
929 idr_init(&pn
->units_idr
);
930 mutex_init(&pn
->all_ppp_mutex
);
932 INIT_LIST_HEAD(&pn
->all_channels
);
933 INIT_LIST_HEAD(&pn
->new_channels
);
935 spin_lock_init(&pn
->all_channels_lock
);
940 static __net_exit
void ppp_exit_net(struct net
*net
)
942 struct ppp_net
*pn
= net_generic(net
, ppp_net_id
);
943 struct net_device
*dev
;
944 struct net_device
*aux
;
950 for_each_netdev_safe(net
, dev
, aux
) {
951 if (dev
->netdev_ops
== &ppp_netdev_ops
)
952 unregister_netdevice_queue(dev
, &list
);
955 idr_for_each_entry(&pn
->units_idr
, ppp
, id
)
956 /* Skip devices already unregistered by previous loop */
957 if (!net_eq(dev_net(ppp
->dev
), net
))
958 unregister_netdevice_queue(ppp
->dev
, &list
);
960 unregister_netdevice_many(&list
);
963 mutex_destroy(&pn
->all_ppp_mutex
);
964 idr_destroy(&pn
->units_idr
);
965 WARN_ON_ONCE(!list_empty(&pn
->all_channels
));
966 WARN_ON_ONCE(!list_empty(&pn
->new_channels
));
969 static struct pernet_operations ppp_net_ops
= {
970 .init
= ppp_init_net
,
971 .exit
= ppp_exit_net
,
973 .size
= sizeof(struct ppp_net
),
976 static int ppp_unit_register(struct ppp
*ppp
, int unit
, bool ifname_is_set
)
978 struct ppp_net
*pn
= ppp_pernet(ppp
->ppp_net
);
981 mutex_lock(&pn
->all_ppp_mutex
);
984 ret
= unit_get(&pn
->units_idr
, ppp
);
988 /* Caller asked for a specific unit number. Fail with -EEXIST
989 * if unavailable. For backward compatibility, return -EEXIST
990 * too if idr allocation fails; this makes pppd retry without
991 * requesting a specific unit number.
993 if (unit_find(&pn
->units_idr
, unit
)) {
997 ret
= unit_set(&pn
->units_idr
, ppp
, unit
);
999 /* Rewrite error for backward compatibility */
1004 ppp
->file
.index
= ret
;
1007 snprintf(ppp
->dev
->name
, IFNAMSIZ
, "ppp%i", ppp
->file
.index
);
1009 ret
= register_netdevice(ppp
->dev
);
1013 atomic_inc(&ppp_unit_count
);
1015 mutex_unlock(&pn
->all_ppp_mutex
);
1020 unit_put(&pn
->units_idr
, ppp
->file
.index
);
1022 mutex_unlock(&pn
->all_ppp_mutex
);
1027 static int ppp_dev_configure(struct net
*src_net
, struct net_device
*dev
,
1028 const struct ppp_config
*conf
)
1030 struct ppp
*ppp
= netdev_priv(dev
);
1036 ppp
->ppp_net
= src_net
;
1038 ppp
->owner
= conf
->file
;
1040 init_ppp_file(&ppp
->file
, INTERFACE
);
1041 ppp
->file
.hdrlen
= PPP_HDRLEN
- 2; /* don't count proto bytes */
1043 for (indx
= 0; indx
< NUM_NP
; ++indx
)
1044 ppp
->npmode
[indx
] = NPMODE_PASS
;
1045 INIT_LIST_HEAD(&ppp
->channels
);
1046 spin_lock_init(&ppp
->rlock
);
1047 spin_lock_init(&ppp
->wlock
);
1049 ppp
->xmit_recursion
= alloc_percpu(int);
1050 if (!ppp
->xmit_recursion
) {
1054 for_each_possible_cpu(cpu
)
1055 (*per_cpu_ptr(ppp
->xmit_recursion
, cpu
)) = 0;
1057 #ifdef CONFIG_PPP_MULTILINK
1059 skb_queue_head_init(&ppp
->mrq
);
1060 #endif /* CONFIG_PPP_MULTILINK */
1061 #ifdef CONFIG_PPP_FILTER
1062 ppp
->pass_filter
= NULL
;
1063 ppp
->active_filter
= NULL
;
1064 #endif /* CONFIG_PPP_FILTER */
1066 err
= ppp_unit_register(ppp
, conf
->unit
, conf
->ifname_is_set
);
1070 conf
->file
->private_data
= &ppp
->file
;
1074 free_percpu(ppp
->xmit_recursion
);
1079 static const struct nla_policy ppp_nl_policy
[IFLA_PPP_MAX
+ 1] = {
1080 [IFLA_PPP_DEV_FD
] = { .type
= NLA_S32
},
1083 static int ppp_nl_validate(struct nlattr
*tb
[], struct nlattr
*data
[],
1084 struct netlink_ext_ack
*extack
)
1089 if (!data
[IFLA_PPP_DEV_FD
])
1091 if (nla_get_s32(data
[IFLA_PPP_DEV_FD
]) < 0)
1097 static int ppp_nl_newlink(struct net
*src_net
, struct net_device
*dev
,
1098 struct nlattr
*tb
[], struct nlattr
*data
[],
1099 struct netlink_ext_ack
*extack
)
1101 struct ppp_config conf
= {
1103 .ifname_is_set
= true,
1108 file
= fget(nla_get_s32(data
[IFLA_PPP_DEV_FD
]));
1112 /* rtnl_lock is already held here, but ppp_create_interface() locks
1113 * ppp_mutex before holding rtnl_lock. Using mutex_trylock() avoids
1114 * possible deadlock due to lock order inversion, at the cost of
1115 * pushing the problem back to userspace.
1117 if (!mutex_trylock(&ppp_mutex
)) {
1122 if (file
->f_op
!= &ppp_device_fops
|| file
->private_data
) {
1129 /* Don't use device name generated by the rtnetlink layer when ifname
1130 * isn't specified. Let ppp_dev_configure() set the device name using
1131 * the PPP unit identifer as suffix (i.e. ppp<unit_id>). This allows
1132 * userspace to infer the device name using to the PPPIOCGUNIT ioctl.
1134 if (!tb
[IFLA_IFNAME
])
1135 conf
.ifname_is_set
= false;
1137 err
= ppp_dev_configure(src_net
, dev
, &conf
);
1140 mutex_unlock(&ppp_mutex
);
1147 static void ppp_nl_dellink(struct net_device
*dev
, struct list_head
*head
)
1149 unregister_netdevice_queue(dev
, head
);
1152 static size_t ppp_nl_get_size(const struct net_device
*dev
)
1157 static int ppp_nl_fill_info(struct sk_buff
*skb
, const struct net_device
*dev
)
1162 static struct net
*ppp_nl_get_link_net(const struct net_device
*dev
)
1164 struct ppp
*ppp
= netdev_priv(dev
);
1166 return ppp
->ppp_net
;
1169 static struct rtnl_link_ops ppp_link_ops __read_mostly
= {
1171 .maxtype
= IFLA_PPP_MAX
,
1172 .policy
= ppp_nl_policy
,
1173 .priv_size
= sizeof(struct ppp
),
1175 .validate
= ppp_nl_validate
,
1176 .newlink
= ppp_nl_newlink
,
1177 .dellink
= ppp_nl_dellink
,
1178 .get_size
= ppp_nl_get_size
,
1179 .fill_info
= ppp_nl_fill_info
,
1180 .get_link_net
= ppp_nl_get_link_net
,
1183 #define PPP_MAJOR 108
1185 /* Called at boot time if ppp is compiled into the kernel,
1186 or at module load time (from init_module) if compiled as a module. */
1187 static int __init
ppp_init(void)
1191 pr_info("PPP generic driver version " PPP_VERSION
"\n");
1193 err
= register_pernet_device(&ppp_net_ops
);
1195 pr_err("failed to register PPP pernet device (%d)\n", err
);
1199 err
= register_chrdev(PPP_MAJOR
, "ppp", &ppp_device_fops
);
1201 pr_err("failed to register PPP device (%d)\n", err
);
1205 ppp_class
= class_create(THIS_MODULE
, "ppp");
1206 if (IS_ERR(ppp_class
)) {
1207 err
= PTR_ERR(ppp_class
);
1211 err
= rtnl_link_register(&ppp_link_ops
);
1213 pr_err("failed to register rtnetlink PPP handler\n");
1217 /* not a big deal if we fail here :-) */
1218 device_create(ppp_class
, NULL
, MKDEV(PPP_MAJOR
, 0), NULL
, "ppp");
1223 class_destroy(ppp_class
);
1225 unregister_chrdev(PPP_MAJOR
, "ppp");
1227 unregister_pernet_device(&ppp_net_ops
);
1233 * Network interface unit routines.
1236 ppp_start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
1238 struct ppp
*ppp
= netdev_priv(dev
);
1242 npi
= ethertype_to_npindex(ntohs(skb
->protocol
));
1246 /* Drop, accept or reject the packet */
1247 switch (ppp
->npmode
[npi
]) {
1251 /* it would be nice to have a way to tell the network
1252 system to queue this one up for later. */
1259 /* Put the 2-byte PPP protocol number on the front,
1260 making sure there is room for the address and control fields. */
1261 if (skb_cow_head(skb
, PPP_HDRLEN
))
1264 pp
= skb_push(skb
, 2);
1265 proto
= npindex_to_proto
[npi
];
1266 put_unaligned_be16(proto
, pp
);
1268 skb_scrub_packet(skb
, !net_eq(ppp
->ppp_net
, dev_net(dev
)));
1269 skb_queue_tail(&ppp
->file
.xq
, skb
);
1270 ppp_xmit_process(ppp
);
1271 return NETDEV_TX_OK
;
1275 ++dev
->stats
.tx_dropped
;
1276 return NETDEV_TX_OK
;
1280 ppp_net_ioctl(struct net_device
*dev
, struct ifreq
*ifr
, int cmd
)
1282 struct ppp
*ppp
= netdev_priv(dev
);
1284 void __user
*addr
= (void __user
*) ifr
->ifr_ifru
.ifru_data
;
1285 struct ppp_stats stats
;
1286 struct ppp_comp_stats cstats
;
1291 ppp_get_stats(ppp
, &stats
);
1292 if (copy_to_user(addr
, &stats
, sizeof(stats
)))
1297 case SIOCGPPPCSTATS
:
1298 memset(&cstats
, 0, sizeof(cstats
));
1300 ppp
->xcomp
->comp_stat(ppp
->xc_state
, &cstats
.c
);
1302 ppp
->rcomp
->decomp_stat(ppp
->rc_state
, &cstats
.d
);
1303 if (copy_to_user(addr
, &cstats
, sizeof(cstats
)))
1310 if (copy_to_user(addr
, vers
, strlen(vers
) + 1))
1323 ppp_get_stats64(struct net_device
*dev
, struct rtnl_link_stats64
*stats64
)
1325 struct ppp
*ppp
= netdev_priv(dev
);
1328 stats64
->rx_packets
= ppp
->stats64
.rx_packets
;
1329 stats64
->rx_bytes
= ppp
->stats64
.rx_bytes
;
1330 ppp_recv_unlock(ppp
);
1333 stats64
->tx_packets
= ppp
->stats64
.tx_packets
;
1334 stats64
->tx_bytes
= ppp
->stats64
.tx_bytes
;
1335 ppp_xmit_unlock(ppp
);
1337 stats64
->rx_errors
= dev
->stats
.rx_errors
;
1338 stats64
->tx_errors
= dev
->stats
.tx_errors
;
1339 stats64
->rx_dropped
= dev
->stats
.rx_dropped
;
1340 stats64
->tx_dropped
= dev
->stats
.tx_dropped
;
1341 stats64
->rx_length_errors
= dev
->stats
.rx_length_errors
;
1344 static int ppp_dev_init(struct net_device
*dev
)
1348 netdev_lockdep_set_classes(dev
);
1350 ppp
= netdev_priv(dev
);
1351 /* Let the netdevice take a reference on the ppp file. This ensures
1352 * that ppp_destroy_interface() won't run before the device gets
1355 refcount_inc(&ppp
->file
.refcnt
);
1360 static void ppp_dev_uninit(struct net_device
*dev
)
1362 struct ppp
*ppp
= netdev_priv(dev
);
1363 struct ppp_net
*pn
= ppp_pernet(ppp
->ppp_net
);
1369 mutex_lock(&pn
->all_ppp_mutex
);
1370 unit_put(&pn
->units_idr
, ppp
->file
.index
);
1371 mutex_unlock(&pn
->all_ppp_mutex
);
1376 wake_up_interruptible(&ppp
->file
.rwait
);
1379 static void ppp_dev_priv_destructor(struct net_device
*dev
)
1383 ppp
= netdev_priv(dev
);
1384 if (refcount_dec_and_test(&ppp
->file
.refcnt
))
1385 ppp_destroy_interface(ppp
);
1388 static const struct net_device_ops ppp_netdev_ops
= {
1389 .ndo_init
= ppp_dev_init
,
1390 .ndo_uninit
= ppp_dev_uninit
,
1391 .ndo_start_xmit
= ppp_start_xmit
,
1392 .ndo_do_ioctl
= ppp_net_ioctl
,
1393 .ndo_get_stats64
= ppp_get_stats64
,
1396 static struct device_type ppp_type
= {
1400 static void ppp_setup(struct net_device
*dev
)
1402 dev
->netdev_ops
= &ppp_netdev_ops
;
1403 SET_NETDEV_DEVTYPE(dev
, &ppp_type
);
1405 dev
->features
|= NETIF_F_LLTX
;
1407 dev
->hard_header_len
= PPP_HDRLEN
;
1410 dev
->tx_queue_len
= 3;
1411 dev
->type
= ARPHRD_PPP
;
1412 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
1413 dev
->priv_destructor
= ppp_dev_priv_destructor
;
1414 netif_keep_dst(dev
);
1418 * Transmit-side routines.
1421 /* Called to do any work queued up on the transmit side that can now be done */
1422 static void __ppp_xmit_process(struct ppp
*ppp
)
1424 struct sk_buff
*skb
;
1427 if (!ppp
->closing
) {
1429 while (!ppp
->xmit_pending
&&
1430 (skb
= skb_dequeue(&ppp
->file
.xq
)))
1431 ppp_send_frame(ppp
, skb
);
1432 /* If there's no work left to do, tell the core net
1433 code that we can accept some more. */
1434 if (!ppp
->xmit_pending
&& !skb_peek(&ppp
->file
.xq
))
1435 netif_wake_queue(ppp
->dev
);
1437 netif_stop_queue(ppp
->dev
);
1439 ppp_xmit_unlock(ppp
);
1442 static void ppp_xmit_process(struct ppp
*ppp
)
1446 if (unlikely(*this_cpu_ptr(ppp
->xmit_recursion
)))
1449 (*this_cpu_ptr(ppp
->xmit_recursion
))++;
1450 __ppp_xmit_process(ppp
);
1451 (*this_cpu_ptr(ppp
->xmit_recursion
))--;
1460 if (net_ratelimit())
1461 netdev_err(ppp
->dev
, "recursion detected\n");
1464 static inline struct sk_buff
*
1465 pad_compress_skb(struct ppp
*ppp
, struct sk_buff
*skb
)
1467 struct sk_buff
*new_skb
;
1469 int new_skb_size
= ppp
->dev
->mtu
+
1470 ppp
->xcomp
->comp_extra
+ ppp
->dev
->hard_header_len
;
1471 int compressor_skb_size
= ppp
->dev
->mtu
+
1472 ppp
->xcomp
->comp_extra
+ PPP_HDRLEN
;
1473 new_skb
= alloc_skb(new_skb_size
, GFP_ATOMIC
);
1475 if (net_ratelimit())
1476 netdev_err(ppp
->dev
, "PPP: no memory (comp pkt)\n");
1479 if (ppp
->dev
->hard_header_len
> PPP_HDRLEN
)
1480 skb_reserve(new_skb
,
1481 ppp
->dev
->hard_header_len
- PPP_HDRLEN
);
1483 /* compressor still expects A/C bytes in hdr */
1484 len
= ppp
->xcomp
->compress(ppp
->xc_state
, skb
->data
- 2,
1485 new_skb
->data
, skb
->len
+ 2,
1486 compressor_skb_size
);
1487 if (len
> 0 && (ppp
->flags
& SC_CCP_UP
)) {
1491 skb_pull(skb
, 2); /* pull off A/C bytes */
1492 } else if (len
== 0) {
1493 /* didn't compress, or CCP not up yet */
1494 consume_skb(new_skb
);
1499 * MPPE requires that we do not send unencrypted
1500 * frames. The compressor will return -1 if we
1501 * should drop the frame. We cannot simply test
1502 * the compress_proto because MPPE and MPPC share
1505 if (net_ratelimit())
1506 netdev_err(ppp
->dev
, "ppp: compressor dropped pkt\n");
1508 consume_skb(new_skb
);
1515 * Compress and send a frame.
1516 * The caller should have locked the xmit path,
1517 * and xmit_pending should be 0.
1520 ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1522 int proto
= PPP_PROTO(skb
);
1523 struct sk_buff
*new_skb
;
1527 if (proto
< 0x8000) {
1528 #ifdef CONFIG_PPP_FILTER
1529 /* check if we should pass this packet */
1530 /* the filter instructions are constructed assuming
1531 a four-byte PPP header on each packet */
1532 *(u8
*)skb_push(skb
, 2) = 1;
1533 if (ppp
->pass_filter
&&
1534 BPF_PROG_RUN(ppp
->pass_filter
, skb
) == 0) {
1536 netdev_printk(KERN_DEBUG
, ppp
->dev
,
1537 "PPP: outbound frame "
1542 /* if this packet passes the active filter, record the time */
1543 if (!(ppp
->active_filter
&&
1544 BPF_PROG_RUN(ppp
->active_filter
, skb
) == 0))
1545 ppp
->last_xmit
= jiffies
;
1548 /* for data packets, record the time */
1549 ppp
->last_xmit
= jiffies
;
1550 #endif /* CONFIG_PPP_FILTER */
1553 ++ppp
->stats64
.tx_packets
;
1554 ppp
->stats64
.tx_bytes
+= skb
->len
- 2;
1558 if (!ppp
->vj
|| (ppp
->flags
& SC_COMP_TCP
) == 0)
1560 /* try to do VJ TCP header compression */
1561 new_skb
= alloc_skb(skb
->len
+ ppp
->dev
->hard_header_len
- 2,
1564 netdev_err(ppp
->dev
, "PPP: no memory (VJ comp pkt)\n");
1567 skb_reserve(new_skb
, ppp
->dev
->hard_header_len
- 2);
1569 len
= slhc_compress(ppp
->vj
, cp
, skb
->len
- 2,
1570 new_skb
->data
+ 2, &cp
,
1571 !(ppp
->flags
& SC_NO_TCP_CCID
));
1572 if (cp
== skb
->data
+ 2) {
1573 /* didn't compress */
1574 consume_skb(new_skb
);
1576 if (cp
[0] & SL_TYPE_COMPRESSED_TCP
) {
1577 proto
= PPP_VJC_COMP
;
1578 cp
[0] &= ~SL_TYPE_COMPRESSED_TCP
;
1580 proto
= PPP_VJC_UNCOMP
;
1581 cp
[0] = skb
->data
[2];
1585 cp
= skb_put(skb
, len
+ 2);
1592 /* peek at outbound CCP frames */
1593 ppp_ccp_peek(ppp
, skb
, 0);
1597 /* try to do packet compression */
1598 if ((ppp
->xstate
& SC_COMP_RUN
) && ppp
->xc_state
&&
1599 proto
!= PPP_LCP
&& proto
!= PPP_CCP
) {
1600 if (!(ppp
->flags
& SC_CCP_UP
) && (ppp
->flags
& SC_MUST_COMP
)) {
1601 if (net_ratelimit())
1602 netdev_err(ppp
->dev
,
1603 "ppp: compression required but "
1604 "down - pkt dropped.\n");
1607 skb
= pad_compress_skb(ppp
, skb
);
1613 * If we are waiting for traffic (demand dialling),
1614 * queue it up for pppd to receive.
1616 if (ppp
->flags
& SC_LOOP_TRAFFIC
) {
1617 if (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
)
1619 skb_queue_tail(&ppp
->file
.rq
, skb
);
1620 wake_up_interruptible(&ppp
->file
.rwait
);
1624 ppp
->xmit_pending
= skb
;
1630 ++ppp
->dev
->stats
.tx_errors
;
1634 * Try to send the frame in xmit_pending.
1635 * The caller should have the xmit path locked.
1638 ppp_push(struct ppp
*ppp
)
1640 struct list_head
*list
;
1641 struct channel
*pch
;
1642 struct sk_buff
*skb
= ppp
->xmit_pending
;
1647 list
= &ppp
->channels
;
1648 if (list_empty(list
)) {
1649 /* nowhere to send the packet, just drop it */
1650 ppp
->xmit_pending
= NULL
;
1655 if ((ppp
->flags
& SC_MULTILINK
) == 0) {
1656 /* not doing multilink: send it down the first channel */
1658 pch
= list_entry(list
, struct channel
, clist
);
1660 spin_lock(&pch
->downl
);
1662 if (pch
->chan
->ops
->start_xmit(pch
->chan
, skb
))
1663 ppp
->xmit_pending
= NULL
;
1665 /* channel got unregistered */
1667 ppp
->xmit_pending
= NULL
;
1669 spin_unlock(&pch
->downl
);
1673 #ifdef CONFIG_PPP_MULTILINK
1674 /* Multilink: fragment the packet over as many links
1675 as can take the packet at the moment. */
1676 if (!ppp_mp_explode(ppp
, skb
))
1678 #endif /* CONFIG_PPP_MULTILINK */
1680 ppp
->xmit_pending
= NULL
;
1684 #ifdef CONFIG_PPP_MULTILINK
1685 static bool mp_protocol_compress __read_mostly
= true;
1686 module_param(mp_protocol_compress
, bool, S_IRUGO
| S_IWUSR
);
1687 MODULE_PARM_DESC(mp_protocol_compress
,
1688 "compress protocol id in multilink fragments");
1691 * Divide a packet to be transmitted into fragments and
1692 * send them out the individual links.
1694 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
)
1697 int i
, bits
, hdrlen
, mtu
;
1699 int navail
, nfree
, nzero
;
1703 unsigned char *p
, *q
;
1704 struct list_head
*list
;
1705 struct channel
*pch
;
1706 struct sk_buff
*frag
;
1707 struct ppp_channel
*chan
;
1709 totspeed
= 0; /*total bitrate of the bundle*/
1710 nfree
= 0; /* # channels which have no packet already queued */
1711 navail
= 0; /* total # of usable channels (not deregistered) */
1712 nzero
= 0; /* number of channels with zero speed associated*/
1713 totfree
= 0; /*total # of channels available and
1714 *having no queued packets before
1715 *starting the fragmentation*/
1717 hdrlen
= (ppp
->flags
& SC_MP_XSHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1719 list_for_each_entry(pch
, &ppp
->channels
, clist
) {
1723 pch
->speed
= pch
->chan
->speed
;
1728 if (skb_queue_empty(&pch
->file
.xq
) ||
1730 if (pch
->speed
== 0)
1733 totspeed
+= pch
->speed
;
1739 if (!pch
->had_frag
&& i
< ppp
->nxchan
)
1745 * Don't start sending this packet unless at least half of
1746 * the channels are free. This gives much better TCP
1747 * performance if we have a lot of channels.
1749 if (nfree
== 0 || nfree
< navail
/ 2)
1750 return 0; /* can't take now, leave it in xmit_pending */
1752 /* Do protocol field compression */
1755 if (*p
== 0 && mp_protocol_compress
) {
1761 nbigger
= len
% nfree
;
1763 /* skip to the channel after the one we last used
1764 and start at that one */
1765 list
= &ppp
->channels
;
1766 for (i
= 0; i
< ppp
->nxchan
; ++i
) {
1768 if (list
== &ppp
->channels
) {
1774 /* create a fragment for each channel */
1778 if (list
== &ppp
->channels
) {
1782 pch
= list_entry(list
, struct channel
, clist
);
1788 * Skip this channel if it has a fragment pending already and
1789 * we haven't given a fragment to all of the free channels.
1791 if (pch
->avail
== 1) {
1798 /* check the channel's mtu and whether it is still attached. */
1799 spin_lock(&pch
->downl
);
1800 if (pch
->chan
== NULL
) {
1801 /* can't use this channel, it's being deregistered */
1802 if (pch
->speed
== 0)
1805 totspeed
-= pch
->speed
;
1807 spin_unlock(&pch
->downl
);
1818 *if the channel speed is not set divide
1819 *the packet evenly among the free channels;
1820 *otherwise divide it according to the speed
1821 *of the channel we are going to transmit on
1825 if (pch
->speed
== 0) {
1832 flen
= (((totfree
- nzero
)*(totlen
+ hdrlen
*totfree
)) /
1833 ((totspeed
*totfree
)/pch
->speed
)) - hdrlen
;
1835 flen
+= ((totfree
- nzero
)*pch
->speed
)/totspeed
;
1836 nbigger
-= ((totfree
- nzero
)*pch
->speed
)/
1844 *check if we are on the last channel or
1845 *we exceded the length of the data to
1848 if ((nfree
<= 0) || (flen
> len
))
1851 *it is not worth to tx on slow channels:
1852 *in that case from the resulting flen according to the
1853 *above formula will be equal or less than zero.
1854 *Skip the channel in this case
1858 spin_unlock(&pch
->downl
);
1863 * hdrlen includes the 2-byte PPP protocol field, but the
1864 * MTU counts only the payload excluding the protocol field.
1865 * (RFC1661 Section 2)
1867 mtu
= pch
->chan
->mtu
- (hdrlen
- 2);
1874 frag
= alloc_skb(flen
+ hdrlen
+ (flen
== 0), GFP_ATOMIC
);
1877 q
= skb_put(frag
, flen
+ hdrlen
);
1879 /* make the MP header */
1880 put_unaligned_be16(PPP_MP
, q
);
1881 if (ppp
->flags
& SC_MP_XSHORTSEQ
) {
1882 q
[2] = bits
+ ((ppp
->nxseq
>> 8) & 0xf);
1886 q
[3] = ppp
->nxseq
>> 16;
1887 q
[4] = ppp
->nxseq
>> 8;
1891 memcpy(q
+ hdrlen
, p
, flen
);
1893 /* try to send it down the channel */
1895 if (!skb_queue_empty(&pch
->file
.xq
) ||
1896 !chan
->ops
->start_xmit(chan
, frag
))
1897 skb_queue_tail(&pch
->file
.xq
, frag
);
1903 spin_unlock(&pch
->downl
);
1910 spin_unlock(&pch
->downl
);
1912 netdev_err(ppp
->dev
, "PPP: no memory (fragment)\n");
1913 ++ppp
->dev
->stats
.tx_errors
;
1915 return 1; /* abandon the frame */
1917 #endif /* CONFIG_PPP_MULTILINK */
1919 /* Try to send data out on a channel */
1920 static void __ppp_channel_push(struct channel
*pch
)
1922 struct sk_buff
*skb
;
1925 spin_lock(&pch
->downl
);
1927 while (!skb_queue_empty(&pch
->file
.xq
)) {
1928 skb
= skb_dequeue(&pch
->file
.xq
);
1929 if (!pch
->chan
->ops
->start_xmit(pch
->chan
, skb
)) {
1930 /* put the packet back and try again later */
1931 skb_queue_head(&pch
->file
.xq
, skb
);
1936 /* channel got deregistered */
1937 skb_queue_purge(&pch
->file
.xq
);
1939 spin_unlock(&pch
->downl
);
1940 /* see if there is anything from the attached unit to be sent */
1941 if (skb_queue_empty(&pch
->file
.xq
)) {
1944 __ppp_xmit_process(ppp
);
1948 static void ppp_channel_push(struct channel
*pch
)
1950 read_lock_bh(&pch
->upl
);
1952 (*this_cpu_ptr(pch
->ppp
->xmit_recursion
))++;
1953 __ppp_channel_push(pch
);
1954 (*this_cpu_ptr(pch
->ppp
->xmit_recursion
))--;
1956 __ppp_channel_push(pch
);
1958 read_unlock_bh(&pch
->upl
);
1962 * Receive-side routines.
1965 struct ppp_mp_skb_parm
{
1969 #define PPP_MP_CB(skb) ((struct ppp_mp_skb_parm *)((skb)->cb))
1972 ppp_do_recv(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1976 ppp_receive_frame(ppp
, skb
, pch
);
1979 ppp_recv_unlock(ppp
);
1983 ppp_input(struct ppp_channel
*chan
, struct sk_buff
*skb
)
1985 struct channel
*pch
= chan
->ppp
;
1993 read_lock_bh(&pch
->upl
);
1994 if (!pskb_may_pull(skb
, 2)) {
1997 ++pch
->ppp
->dev
->stats
.rx_length_errors
;
1998 ppp_receive_error(pch
->ppp
);
2003 proto
= PPP_PROTO(skb
);
2004 if (!pch
->ppp
|| proto
>= 0xc000 || proto
== PPP_CCPFRAG
) {
2005 /* put it on the channel queue */
2006 skb_queue_tail(&pch
->file
.rq
, skb
);
2007 /* drop old frames if queue too long */
2008 while (pch
->file
.rq
.qlen
> PPP_MAX_RQLEN
&&
2009 (skb
= skb_dequeue(&pch
->file
.rq
)))
2011 wake_up_interruptible(&pch
->file
.rwait
);
2013 ppp_do_recv(pch
->ppp
, skb
, pch
);
2017 read_unlock_bh(&pch
->upl
);
2020 /* Put a 0-length skb in the receive queue as an error indication */
2022 ppp_input_error(struct ppp_channel
*chan
, int code
)
2024 struct channel
*pch
= chan
->ppp
;
2025 struct sk_buff
*skb
;
2030 read_lock_bh(&pch
->upl
);
2032 skb
= alloc_skb(0, GFP_ATOMIC
);
2034 skb
->len
= 0; /* probably unnecessary */
2036 ppp_do_recv(pch
->ppp
, skb
, pch
);
2039 read_unlock_bh(&pch
->upl
);
2043 * We come in here to process a received frame.
2044 * The receive side of the ppp unit is locked.
2047 ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
2049 /* note: a 0-length skb is used as an error indication */
2051 skb_checksum_complete_unset(skb
);
2052 #ifdef CONFIG_PPP_MULTILINK
2053 /* XXX do channel-level decompression here */
2054 if (PPP_PROTO(skb
) == PPP_MP
)
2055 ppp_receive_mp_frame(ppp
, skb
, pch
);
2057 #endif /* CONFIG_PPP_MULTILINK */
2058 ppp_receive_nonmp_frame(ppp
, skb
);
2061 ppp_receive_error(ppp
);
2066 ppp_receive_error(struct ppp
*ppp
)
2068 ++ppp
->dev
->stats
.rx_errors
;
2074 ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
2077 int proto
, len
, npi
;
2080 * Decompress the frame, if compressed.
2081 * Note that some decompressors need to see uncompressed frames
2082 * that come in as well as compressed frames.
2084 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
) &&
2085 (ppp
->rstate
& (SC_DC_FERROR
| SC_DC_ERROR
)) == 0)
2086 skb
= ppp_decompress_frame(ppp
, skb
);
2088 if (ppp
->flags
& SC_MUST_COMP
&& ppp
->rstate
& SC_DC_FERROR
)
2091 proto
= PPP_PROTO(skb
);
2094 /* decompress VJ compressed packets */
2095 if (!ppp
->vj
|| (ppp
->flags
& SC_REJ_COMP_TCP
))
2098 if (skb_tailroom(skb
) < 124 || skb_cloned(skb
)) {
2099 /* copy to a new sk_buff with more tailroom */
2100 ns
= dev_alloc_skb(skb
->len
+ 128);
2102 netdev_err(ppp
->dev
, "PPP: no memory "
2107 skb_copy_bits(skb
, 0, skb_put(ns
, skb
->len
), skb
->len
);
2112 skb
->ip_summed
= CHECKSUM_NONE
;
2114 len
= slhc_uncompress(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2);
2116 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2117 "PPP: VJ decompression error\n");
2122 skb_put(skb
, len
- skb
->len
);
2123 else if (len
< skb
->len
)
2128 case PPP_VJC_UNCOMP
:
2129 if (!ppp
->vj
|| (ppp
->flags
& SC_REJ_COMP_TCP
))
2132 /* Until we fix the decompressor need to make sure
2133 * data portion is linear.
2135 if (!pskb_may_pull(skb
, skb
->len
))
2138 if (slhc_remember(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2) <= 0) {
2139 netdev_err(ppp
->dev
, "PPP: VJ uncompressed error\n");
2146 ppp_ccp_peek(ppp
, skb
, 1);
2150 ++ppp
->stats64
.rx_packets
;
2151 ppp
->stats64
.rx_bytes
+= skb
->len
- 2;
2153 npi
= proto_to_npindex(proto
);
2155 /* control or unknown frame - pass it to pppd */
2156 skb_queue_tail(&ppp
->file
.rq
, skb
);
2157 /* limit queue length by dropping old frames */
2158 while (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
&&
2159 (skb
= skb_dequeue(&ppp
->file
.rq
)))
2161 /* wake up any process polling or blocking on read */
2162 wake_up_interruptible(&ppp
->file
.rwait
);
2165 /* network protocol frame - give it to the kernel */
2167 #ifdef CONFIG_PPP_FILTER
2168 /* check if the packet passes the pass and active filters */
2169 /* the filter instructions are constructed assuming
2170 a four-byte PPP header on each packet */
2171 if (ppp
->pass_filter
|| ppp
->active_filter
) {
2172 if (skb_unclone(skb
, GFP_ATOMIC
))
2175 *(u8
*)skb_push(skb
, 2) = 0;
2176 if (ppp
->pass_filter
&&
2177 BPF_PROG_RUN(ppp
->pass_filter
, skb
) == 0) {
2179 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2180 "PPP: inbound frame "
2185 if (!(ppp
->active_filter
&&
2186 BPF_PROG_RUN(ppp
->active_filter
, skb
) == 0))
2187 ppp
->last_recv
= jiffies
;
2190 #endif /* CONFIG_PPP_FILTER */
2191 ppp
->last_recv
= jiffies
;
2193 if ((ppp
->dev
->flags
& IFF_UP
) == 0 ||
2194 ppp
->npmode
[npi
] != NPMODE_PASS
) {
2197 /* chop off protocol */
2198 skb_pull_rcsum(skb
, 2);
2199 skb
->dev
= ppp
->dev
;
2200 skb
->protocol
= htons(npindex_to_ethertype
[npi
]);
2201 skb_reset_mac_header(skb
);
2202 skb_scrub_packet(skb
, !net_eq(ppp
->ppp_net
,
2203 dev_net(ppp
->dev
)));
2211 ppp_receive_error(ppp
);
2214 static struct sk_buff
*
2215 ppp_decompress_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
2217 int proto
= PPP_PROTO(skb
);
2221 /* Until we fix all the decompressor's need to make sure
2222 * data portion is linear.
2224 if (!pskb_may_pull(skb
, skb
->len
))
2227 if (proto
== PPP_COMP
) {
2230 switch(ppp
->rcomp
->compress_proto
) {
2232 obuff_size
= ppp
->mru
+ PPP_HDRLEN
+ 1;
2235 obuff_size
= ppp
->mru
+ PPP_HDRLEN
;
2239 ns
= dev_alloc_skb(obuff_size
);
2241 netdev_err(ppp
->dev
, "ppp_decompress_frame: "
2245 /* the decompressor still expects the A/C bytes in the hdr */
2246 len
= ppp
->rcomp
->decompress(ppp
->rc_state
, skb
->data
- 2,
2247 skb
->len
+ 2, ns
->data
, obuff_size
);
2249 /* Pass the compressed frame to pppd as an
2250 error indication. */
2251 if (len
== DECOMP_FATALERROR
)
2252 ppp
->rstate
|= SC_DC_FERROR
;
2260 skb_pull(skb
, 2); /* pull off the A/C bytes */
2263 /* Uncompressed frame - pass to decompressor so it
2264 can update its dictionary if necessary. */
2265 if (ppp
->rcomp
->incomp
)
2266 ppp
->rcomp
->incomp(ppp
->rc_state
, skb
->data
- 2,
2273 ppp
->rstate
|= SC_DC_ERROR
;
2274 ppp_receive_error(ppp
);
2278 #ifdef CONFIG_PPP_MULTILINK
2280 * Receive a multilink frame.
2281 * We put it on the reconstruction queue and then pull off
2282 * as many completed frames as we can.
2285 ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
2289 int mphdrlen
= (ppp
->flags
& SC_MP_SHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
2291 if (!pskb_may_pull(skb
, mphdrlen
+ 1) || ppp
->mrru
== 0)
2292 goto err
; /* no good, throw it away */
2294 /* Decode sequence number and begin/end bits */
2295 if (ppp
->flags
& SC_MP_SHORTSEQ
) {
2296 seq
= ((skb
->data
[2] & 0x0f) << 8) | skb
->data
[3];
2299 seq
= (skb
->data
[3] << 16) | (skb
->data
[4] << 8)| skb
->data
[5];
2302 PPP_MP_CB(skb
)->BEbits
= skb
->data
[2];
2303 skb_pull(skb
, mphdrlen
); /* pull off PPP and MP headers */
2306 * Do protocol ID decompression on the first fragment of each packet.
2308 if ((PPP_MP_CB(skb
)->BEbits
& B
) && (skb
->data
[0] & 1))
2309 *(u8
*)skb_push(skb
, 1) = 0;
2312 * Expand sequence number to 32 bits, making it as close
2313 * as possible to ppp->minseq.
2315 seq
|= ppp
->minseq
& ~mask
;
2316 if ((int)(ppp
->minseq
- seq
) > (int)(mask
>> 1))
2318 else if ((int)(seq
- ppp
->minseq
) > (int)(mask
>> 1))
2319 seq
-= mask
+ 1; /* should never happen */
2320 PPP_MP_CB(skb
)->sequence
= seq
;
2324 * If this packet comes before the next one we were expecting,
2327 if (seq_before(seq
, ppp
->nextseq
)) {
2329 ++ppp
->dev
->stats
.rx_dropped
;
2330 ppp_receive_error(ppp
);
2335 * Reevaluate minseq, the minimum over all channels of the
2336 * last sequence number received on each channel. Because of
2337 * the increasing sequence number rule, we know that any fragment
2338 * before `minseq' which hasn't arrived is never going to arrive.
2339 * The list of channels can't change because we have the receive
2340 * side of the ppp unit locked.
2342 list_for_each_entry(ch
, &ppp
->channels
, clist
) {
2343 if (seq_before(ch
->lastseq
, seq
))
2346 if (seq_before(ppp
->minseq
, seq
))
2349 /* Put the fragment on the reconstruction queue */
2350 ppp_mp_insert(ppp
, skb
);
2352 /* If the queue is getting long, don't wait any longer for packets
2353 before the start of the queue. */
2354 if (skb_queue_len(&ppp
->mrq
) >= PPP_MP_MAX_QLEN
) {
2355 struct sk_buff
*mskb
= skb_peek(&ppp
->mrq
);
2356 if (seq_before(ppp
->minseq
, PPP_MP_CB(mskb
)->sequence
))
2357 ppp
->minseq
= PPP_MP_CB(mskb
)->sequence
;
2360 /* Pull completed packets off the queue and receive them. */
2361 while ((skb
= ppp_mp_reconstruct(ppp
))) {
2362 if (pskb_may_pull(skb
, 2))
2363 ppp_receive_nonmp_frame(ppp
, skb
);
2365 ++ppp
->dev
->stats
.rx_length_errors
;
2367 ppp_receive_error(ppp
);
2375 ppp_receive_error(ppp
);
2379 * Insert a fragment on the MP reconstruction queue.
2380 * The queue is ordered by increasing sequence number.
2383 ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
)
2386 struct sk_buff_head
*list
= &ppp
->mrq
;
2387 u32 seq
= PPP_MP_CB(skb
)->sequence
;
2389 /* N.B. we don't need to lock the list lock because we have the
2390 ppp unit receive-side lock. */
2391 skb_queue_walk(list
, p
) {
2392 if (seq_before(seq
, PPP_MP_CB(p
)->sequence
))
2395 __skb_queue_before(list
, p
, skb
);
2399 * Reconstruct a packet from the MP fragment queue.
2400 * We go through increasing sequence numbers until we find a
2401 * complete packet, or we get to the sequence number for a fragment
2402 * which hasn't arrived but might still do so.
2404 static struct sk_buff
*
2405 ppp_mp_reconstruct(struct ppp
*ppp
)
2407 u32 seq
= ppp
->nextseq
;
2408 u32 minseq
= ppp
->minseq
;
2409 struct sk_buff_head
*list
= &ppp
->mrq
;
2410 struct sk_buff
*p
, *tmp
;
2411 struct sk_buff
*head
, *tail
;
2412 struct sk_buff
*skb
= NULL
;
2413 int lost
= 0, len
= 0;
2415 if (ppp
->mrru
== 0) /* do nothing until mrru is set */
2419 skb_queue_walk_safe(list
, p
, tmp
) {
2421 if (seq_before(PPP_MP_CB(p
)->sequence
, seq
)) {
2422 /* this can't happen, anyway ignore the skb */
2423 netdev_err(ppp
->dev
, "ppp_mp_reconstruct bad "
2425 PPP_MP_CB(p
)->sequence
, seq
);
2426 __skb_unlink(p
, list
);
2430 if (PPP_MP_CB(p
)->sequence
!= seq
) {
2432 /* Fragment `seq' is missing. If it is after
2433 minseq, it might arrive later, so stop here. */
2434 if (seq_after(seq
, minseq
))
2436 /* Fragment `seq' is lost, keep going. */
2439 seq
= seq_before(minseq
, PPP_MP_CB(p
)->sequence
)?
2440 minseq
+ 1: PPP_MP_CB(p
)->sequence
;
2443 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2444 "lost frag %u..%u\n",
2451 * At this point we know that all the fragments from
2452 * ppp->nextseq to seq are either present or lost.
2453 * Also, there are no complete packets in the queue
2454 * that have no missing fragments and end before this
2458 /* B bit set indicates this fragment starts a packet */
2459 if (PPP_MP_CB(p
)->BEbits
& B
) {
2467 /* Got a complete packet yet? */
2468 if (lost
== 0 && (PPP_MP_CB(p
)->BEbits
& E
) &&
2469 (PPP_MP_CB(head
)->BEbits
& B
)) {
2470 if (len
> ppp
->mrru
+ 2) {
2471 ++ppp
->dev
->stats
.rx_length_errors
;
2472 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2473 "PPP: reconstructed packet"
2474 " is too long (%d)\n", len
);
2479 ppp
->nextseq
= seq
+ 1;
2483 * If this is the ending fragment of a packet,
2484 * and we haven't found a complete valid packet yet,
2485 * we can discard up to and including this fragment.
2487 if (PPP_MP_CB(p
)->BEbits
& E
) {
2488 struct sk_buff
*tmp2
;
2490 skb_queue_reverse_walk_from_safe(list
, p
, tmp2
) {
2492 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2493 "discarding frag %u\n",
2494 PPP_MP_CB(p
)->sequence
);
2495 __skb_unlink(p
, list
);
2498 head
= skb_peek(list
);
2505 /* If we have a complete packet, copy it all into one skb. */
2507 /* If we have discarded any fragments,
2508 signal a receive error. */
2509 if (PPP_MP_CB(head
)->sequence
!= ppp
->nextseq
) {
2510 skb_queue_walk_safe(list
, p
, tmp
) {
2514 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2515 "discarding frag %u\n",
2516 PPP_MP_CB(p
)->sequence
);
2517 __skb_unlink(p
, list
);
2522 netdev_printk(KERN_DEBUG
, ppp
->dev
,
2523 " missed pkts %u..%u\n",
2525 PPP_MP_CB(head
)->sequence
-1);
2526 ++ppp
->dev
->stats
.rx_dropped
;
2527 ppp_receive_error(ppp
);
2532 struct sk_buff
**fragpp
= &skb_shinfo(skb
)->frag_list
;
2533 p
= skb_queue_next(list
, head
);
2534 __skb_unlink(skb
, list
);
2535 skb_queue_walk_from_safe(list
, p
, tmp
) {
2536 __skb_unlink(p
, list
);
2542 skb
->data_len
+= p
->len
;
2543 skb
->truesize
+= p
->truesize
;
2549 __skb_unlink(skb
, list
);
2552 ppp
->nextseq
= PPP_MP_CB(tail
)->sequence
+ 1;
2557 #endif /* CONFIG_PPP_MULTILINK */
2560 * Channel interface.
2563 /* Create a new, unattached ppp channel. */
2564 int ppp_register_channel(struct ppp_channel
*chan
)
2566 return ppp_register_net_channel(current
->nsproxy
->net_ns
, chan
);
2569 /* Create a new, unattached ppp channel for specified net. */
2570 int ppp_register_net_channel(struct net
*net
, struct ppp_channel
*chan
)
2572 struct channel
*pch
;
2575 pch
= kzalloc(sizeof(struct channel
), GFP_KERNEL
);
2579 pn
= ppp_pernet(net
);
2583 pch
->chan_net
= get_net(net
);
2585 init_ppp_file(&pch
->file
, CHANNEL
);
2586 pch
->file
.hdrlen
= chan
->hdrlen
;
2587 #ifdef CONFIG_PPP_MULTILINK
2589 #endif /* CONFIG_PPP_MULTILINK */
2590 init_rwsem(&pch
->chan_sem
);
2591 spin_lock_init(&pch
->downl
);
2592 rwlock_init(&pch
->upl
);
2594 spin_lock_bh(&pn
->all_channels_lock
);
2595 pch
->file
.index
= ++pn
->last_channel_index
;
2596 list_add(&pch
->list
, &pn
->new_channels
);
2597 atomic_inc(&channel_count
);
2598 spin_unlock_bh(&pn
->all_channels_lock
);
2604 * Return the index of a channel.
2606 int ppp_channel_index(struct ppp_channel
*chan
)
2608 struct channel
*pch
= chan
->ppp
;
2611 return pch
->file
.index
;
2616 * Return the PPP unit number to which a channel is connected.
2618 int ppp_unit_number(struct ppp_channel
*chan
)
2620 struct channel
*pch
= chan
->ppp
;
2624 read_lock_bh(&pch
->upl
);
2626 unit
= pch
->ppp
->file
.index
;
2627 read_unlock_bh(&pch
->upl
);
2633 * Return the PPP device interface name of a channel.
2635 char *ppp_dev_name(struct ppp_channel
*chan
)
2637 struct channel
*pch
= chan
->ppp
;
2641 read_lock_bh(&pch
->upl
);
2642 if (pch
->ppp
&& pch
->ppp
->dev
)
2643 name
= pch
->ppp
->dev
->name
;
2644 read_unlock_bh(&pch
->upl
);
2651 * Disconnect a channel from the generic layer.
2652 * This must be called in process context.
2655 ppp_unregister_channel(struct ppp_channel
*chan
)
2657 struct channel
*pch
= chan
->ppp
;
2661 return; /* should never happen */
2666 * This ensures that we have returned from any calls into the
2667 * the channel's start_xmit or ioctl routine before we proceed.
2669 down_write(&pch
->chan_sem
);
2670 spin_lock_bh(&pch
->downl
);
2672 spin_unlock_bh(&pch
->downl
);
2673 up_write(&pch
->chan_sem
);
2674 ppp_disconnect_channel(pch
);
2676 pn
= ppp_pernet(pch
->chan_net
);
2677 spin_lock_bh(&pn
->all_channels_lock
);
2678 list_del(&pch
->list
);
2679 spin_unlock_bh(&pn
->all_channels_lock
);
2682 wake_up_interruptible(&pch
->file
.rwait
);
2683 if (refcount_dec_and_test(&pch
->file
.refcnt
))
2684 ppp_destroy_channel(pch
);
2688 * Callback from a channel when it can accept more to transmit.
2689 * This should be called at BH/softirq level, not interrupt level.
2692 ppp_output_wakeup(struct ppp_channel
*chan
)
2694 struct channel
*pch
= chan
->ppp
;
2698 ppp_channel_push(pch
);
2702 * Compression control.
2705 /* Process the PPPIOCSCOMPRESS ioctl. */
2707 ppp_set_compress(struct ppp
*ppp
, unsigned long arg
)
2710 struct compressor
*cp
, *ocomp
;
2711 struct ppp_option_data data
;
2712 void *state
, *ostate
;
2713 unsigned char ccp_option
[CCP_MAX_OPTION_LENGTH
];
2716 if (copy_from_user(&data
, (void __user
*) arg
, sizeof(data
)))
2718 if (data
.length
> CCP_MAX_OPTION_LENGTH
)
2720 if (copy_from_user(ccp_option
, (void __user
*) data
.ptr
, data
.length
))
2724 if (data
.length
< 2 || ccp_option
[1] < 2 || ccp_option
[1] > data
.length
)
2727 cp
= try_then_request_module(
2728 find_compressor(ccp_option
[0]),
2729 "ppp-compress-%d", ccp_option
[0]);
2734 if (data
.transmit
) {
2735 state
= cp
->comp_alloc(ccp_option
, data
.length
);
2738 ppp
->xstate
&= ~SC_COMP_RUN
;
2740 ostate
= ppp
->xc_state
;
2742 ppp
->xc_state
= state
;
2743 ppp_xmit_unlock(ppp
);
2745 ocomp
->comp_free(ostate
);
2746 module_put(ocomp
->owner
);
2750 module_put(cp
->owner
);
2753 state
= cp
->decomp_alloc(ccp_option
, data
.length
);
2756 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2758 ostate
= ppp
->rc_state
;
2760 ppp
->rc_state
= state
;
2761 ppp_recv_unlock(ppp
);
2763 ocomp
->decomp_free(ostate
);
2764 module_put(ocomp
->owner
);
2768 module_put(cp
->owner
);
2776 * Look at a CCP packet and update our state accordingly.
2777 * We assume the caller has the xmit or recv path locked.
2780 ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
)
2785 if (!pskb_may_pull(skb
, CCP_HDRLEN
+ 2))
2786 return; /* no header */
2789 switch (CCP_CODE(dp
)) {
2792 /* A ConfReq starts negotiation of compression
2793 * in one direction of transmission,
2794 * and hence brings it down...but which way?
2797 * A ConfReq indicates what the sender would like to receive
2800 /* He is proposing what I should send */
2801 ppp
->xstate
&= ~SC_COMP_RUN
;
2803 /* I am proposing to what he should send */
2804 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2811 * CCP is going down, both directions of transmission
2813 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2814 ppp
->xstate
&= ~SC_COMP_RUN
;
2818 if ((ppp
->flags
& (SC_CCP_OPEN
| SC_CCP_UP
)) != SC_CCP_OPEN
)
2820 len
= CCP_LENGTH(dp
);
2821 if (!pskb_may_pull(skb
, len
+ 2))
2822 return; /* too short */
2825 if (len
< CCP_OPT_MINLEN
|| len
< CCP_OPT_LENGTH(dp
))
2828 /* we will start receiving compressed packets */
2831 if (ppp
->rcomp
->decomp_init(ppp
->rc_state
, dp
, len
,
2832 ppp
->file
.index
, 0, ppp
->mru
, ppp
->debug
)) {
2833 ppp
->rstate
|= SC_DECOMP_RUN
;
2834 ppp
->rstate
&= ~(SC_DC_ERROR
| SC_DC_FERROR
);
2837 /* we will soon start sending compressed packets */
2840 if (ppp
->xcomp
->comp_init(ppp
->xc_state
, dp
, len
,
2841 ppp
->file
.index
, 0, ppp
->debug
))
2842 ppp
->xstate
|= SC_COMP_RUN
;
2847 /* reset the [de]compressor */
2848 if ((ppp
->flags
& SC_CCP_UP
) == 0)
2851 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
)) {
2852 ppp
->rcomp
->decomp_reset(ppp
->rc_state
);
2853 ppp
->rstate
&= ~SC_DC_ERROR
;
2856 if (ppp
->xc_state
&& (ppp
->xstate
& SC_COMP_RUN
))
2857 ppp
->xcomp
->comp_reset(ppp
->xc_state
);
2863 /* Free up compression resources. */
2865 ppp_ccp_closed(struct ppp
*ppp
)
2867 void *xstate
, *rstate
;
2868 struct compressor
*xcomp
, *rcomp
;
2871 ppp
->flags
&= ~(SC_CCP_OPEN
| SC_CCP_UP
);
2874 xstate
= ppp
->xc_state
;
2875 ppp
->xc_state
= NULL
;
2878 rstate
= ppp
->rc_state
;
2879 ppp
->rc_state
= NULL
;
2883 xcomp
->comp_free(xstate
);
2884 module_put(xcomp
->owner
);
2887 rcomp
->decomp_free(rstate
);
2888 module_put(rcomp
->owner
);
2892 /* List of compressors. */
2893 static LIST_HEAD(compressor_list
);
2894 static DEFINE_SPINLOCK(compressor_list_lock
);
2896 struct compressor_entry
{
2897 struct list_head list
;
2898 struct compressor
*comp
;
2901 static struct compressor_entry
*
2902 find_comp_entry(int proto
)
2904 struct compressor_entry
*ce
;
2906 list_for_each_entry(ce
, &compressor_list
, list
) {
2907 if (ce
->comp
->compress_proto
== proto
)
2913 /* Register a compressor */
2915 ppp_register_compressor(struct compressor
*cp
)
2917 struct compressor_entry
*ce
;
2919 spin_lock(&compressor_list_lock
);
2921 if (find_comp_entry(cp
->compress_proto
))
2924 ce
= kmalloc(sizeof(struct compressor_entry
), GFP_ATOMIC
);
2929 list_add(&ce
->list
, &compressor_list
);
2931 spin_unlock(&compressor_list_lock
);
2935 /* Unregister a compressor */
2937 ppp_unregister_compressor(struct compressor
*cp
)
2939 struct compressor_entry
*ce
;
2941 spin_lock(&compressor_list_lock
);
2942 ce
= find_comp_entry(cp
->compress_proto
);
2943 if (ce
&& ce
->comp
== cp
) {
2944 list_del(&ce
->list
);
2947 spin_unlock(&compressor_list_lock
);
2950 /* Find a compressor. */
2951 static struct compressor
*
2952 find_compressor(int type
)
2954 struct compressor_entry
*ce
;
2955 struct compressor
*cp
= NULL
;
2957 spin_lock(&compressor_list_lock
);
2958 ce
= find_comp_entry(type
);
2961 if (!try_module_get(cp
->owner
))
2964 spin_unlock(&compressor_list_lock
);
2969 * Miscelleneous stuff.
2973 ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
)
2975 struct slcompress
*vj
= ppp
->vj
;
2977 memset(st
, 0, sizeof(*st
));
2978 st
->p
.ppp_ipackets
= ppp
->stats64
.rx_packets
;
2979 st
->p
.ppp_ierrors
= ppp
->dev
->stats
.rx_errors
;
2980 st
->p
.ppp_ibytes
= ppp
->stats64
.rx_bytes
;
2981 st
->p
.ppp_opackets
= ppp
->stats64
.tx_packets
;
2982 st
->p
.ppp_oerrors
= ppp
->dev
->stats
.tx_errors
;
2983 st
->p
.ppp_obytes
= ppp
->stats64
.tx_bytes
;
2986 st
->vj
.vjs_packets
= vj
->sls_o_compressed
+ vj
->sls_o_uncompressed
;
2987 st
->vj
.vjs_compressed
= vj
->sls_o_compressed
;
2988 st
->vj
.vjs_searches
= vj
->sls_o_searches
;
2989 st
->vj
.vjs_misses
= vj
->sls_o_misses
;
2990 st
->vj
.vjs_errorin
= vj
->sls_i_error
;
2991 st
->vj
.vjs_tossed
= vj
->sls_i_tossed
;
2992 st
->vj
.vjs_uncompressedin
= vj
->sls_i_uncompressed
;
2993 st
->vj
.vjs_compressedin
= vj
->sls_i_compressed
;
2997 * Stuff for handling the lists of ppp units and channels
2998 * and for initialization.
3002 * Create a new ppp interface unit. Fails if it can't allocate memory
3003 * or if there is already a unit with the requested number.
3004 * unit == -1 means allocate a new number.
3006 static int ppp_create_interface(struct net
*net
, struct file
*file
, int *unit
)
3008 struct ppp_config conf
= {
3011 .ifname_is_set
= false,
3013 struct net_device
*dev
;
3017 dev
= alloc_netdev(sizeof(struct ppp
), "", NET_NAME_ENUM
, ppp_setup
);
3022 dev_net_set(dev
, net
);
3023 dev
->rtnl_link_ops
= &ppp_link_ops
;
3027 err
= ppp_dev_configure(net
, dev
, &conf
);
3030 ppp
= netdev_priv(dev
);
3031 *unit
= ppp
->file
.index
;
3045 * Initialize a ppp_file structure.
3048 init_ppp_file(struct ppp_file
*pf
, int kind
)
3051 skb_queue_head_init(&pf
->xq
);
3052 skb_queue_head_init(&pf
->rq
);
3053 refcount_set(&pf
->refcnt
, 1);
3054 init_waitqueue_head(&pf
->rwait
);
3058 * Free the memory used by a ppp unit. This is only called once
3059 * there are no channels connected to the unit and no file structs
3060 * that reference the unit.
3062 static void ppp_destroy_interface(struct ppp
*ppp
)
3064 atomic_dec(&ppp_unit_count
);
3066 if (!ppp
->file
.dead
|| ppp
->n_channels
) {
3067 /* "can't happen" */
3068 netdev_err(ppp
->dev
, "ppp: destroying ppp struct %p "
3069 "but dead=%d n_channels=%d !\n",
3070 ppp
, ppp
->file
.dead
, ppp
->n_channels
);
3074 ppp_ccp_closed(ppp
);
3079 skb_queue_purge(&ppp
->file
.xq
);
3080 skb_queue_purge(&ppp
->file
.rq
);
3081 #ifdef CONFIG_PPP_MULTILINK
3082 skb_queue_purge(&ppp
->mrq
);
3083 #endif /* CONFIG_PPP_MULTILINK */
3084 #ifdef CONFIG_PPP_FILTER
3085 if (ppp
->pass_filter
) {
3086 bpf_prog_destroy(ppp
->pass_filter
);
3087 ppp
->pass_filter
= NULL
;
3090 if (ppp
->active_filter
) {
3091 bpf_prog_destroy(ppp
->active_filter
);
3092 ppp
->active_filter
= NULL
;
3094 #endif /* CONFIG_PPP_FILTER */
3096 kfree_skb(ppp
->xmit_pending
);
3097 free_percpu(ppp
->xmit_recursion
);
3099 free_netdev(ppp
->dev
);
3103 * Locate an existing ppp unit.
3104 * The caller should have locked the all_ppp_mutex.
3107 ppp_find_unit(struct ppp_net
*pn
, int unit
)
3109 return unit_find(&pn
->units_idr
, unit
);
3113 * Locate an existing ppp channel.
3114 * The caller should have locked the all_channels_lock.
3115 * First we look in the new_channels list, then in the
3116 * all_channels list. If found in the new_channels list,
3117 * we move it to the all_channels list. This is for speed
3118 * when we have a lot of channels in use.
3120 static struct channel
*
3121 ppp_find_channel(struct ppp_net
*pn
, int unit
)
3123 struct channel
*pch
;
3125 list_for_each_entry(pch
, &pn
->new_channels
, list
) {
3126 if (pch
->file
.index
== unit
) {
3127 list_move(&pch
->list
, &pn
->all_channels
);
3132 list_for_each_entry(pch
, &pn
->all_channels
, list
) {
3133 if (pch
->file
.index
== unit
)
3141 * Connect a PPP channel to a PPP interface unit.
3144 ppp_connect_channel(struct channel
*pch
, int unit
)
3151 pn
= ppp_pernet(pch
->chan_net
);
3153 mutex_lock(&pn
->all_ppp_mutex
);
3154 ppp
= ppp_find_unit(pn
, unit
);
3157 write_lock_bh(&pch
->upl
);
3163 if (pch
->file
.hdrlen
> ppp
->file
.hdrlen
)
3164 ppp
->file
.hdrlen
= pch
->file
.hdrlen
;
3165 hdrlen
= pch
->file
.hdrlen
+ 2; /* for protocol bytes */
3166 if (hdrlen
> ppp
->dev
->hard_header_len
)
3167 ppp
->dev
->hard_header_len
= hdrlen
;
3168 list_add_tail(&pch
->clist
, &ppp
->channels
);
3171 refcount_inc(&ppp
->file
.refcnt
);
3176 write_unlock_bh(&pch
->upl
);
3178 mutex_unlock(&pn
->all_ppp_mutex
);
3183 * Disconnect a channel from its ppp unit.
3186 ppp_disconnect_channel(struct channel
*pch
)
3191 write_lock_bh(&pch
->upl
);
3194 write_unlock_bh(&pch
->upl
);
3196 /* remove it from the ppp unit's list */
3198 list_del(&pch
->clist
);
3199 if (--ppp
->n_channels
== 0)
3200 wake_up_interruptible(&ppp
->file
.rwait
);
3202 if (refcount_dec_and_test(&ppp
->file
.refcnt
))
3203 ppp_destroy_interface(ppp
);
3210 * Free up the resources used by a ppp channel.
3212 static void ppp_destroy_channel(struct channel
*pch
)
3214 put_net(pch
->chan_net
);
3215 pch
->chan_net
= NULL
;
3217 atomic_dec(&channel_count
);
3219 if (!pch
->file
.dead
) {
3220 /* "can't happen" */
3221 pr_err("ppp: destroying undead channel %p !\n", pch
);
3224 skb_queue_purge(&pch
->file
.xq
);
3225 skb_queue_purge(&pch
->file
.rq
);
3229 static void __exit
ppp_cleanup(void)
3231 /* should never happen */
3232 if (atomic_read(&ppp_unit_count
) || atomic_read(&channel_count
))
3233 pr_err("PPP: removing module but units remain!\n");
3234 rtnl_link_unregister(&ppp_link_ops
);
3235 unregister_chrdev(PPP_MAJOR
, "ppp");
3236 device_destroy(ppp_class
, MKDEV(PPP_MAJOR
, 0));
3237 class_destroy(ppp_class
);
3238 unregister_pernet_device(&ppp_net_ops
);
3242 * Units handling. Caller must protect concurrent access
3243 * by holding all_ppp_mutex
3246 /* associate pointer with specified number */
3247 static int unit_set(struct idr
*p
, void *ptr
, int n
)
3251 unit
= idr_alloc(p
, ptr
, n
, n
+ 1, GFP_KERNEL
);
3252 if (unit
== -ENOSPC
)
3257 /* get new free unit number and associate pointer with it */
3258 static int unit_get(struct idr
*p
, void *ptr
)
3260 return idr_alloc(p
, ptr
, 0, 0, GFP_KERNEL
);
3263 /* put unit number back to a pool */
3264 static void unit_put(struct idr
*p
, int n
)
3269 /* get pointer associated with the number */
3270 static void *unit_find(struct idr
*p
, int n
)
3272 return idr_find(p
, n
);
3275 /* Module/initialization stuff */
3277 module_init(ppp_init
);
3278 module_exit(ppp_cleanup
);
3280 EXPORT_SYMBOL(ppp_register_net_channel
);
3281 EXPORT_SYMBOL(ppp_register_channel
);
3282 EXPORT_SYMBOL(ppp_unregister_channel
);
3283 EXPORT_SYMBOL(ppp_channel_index
);
3284 EXPORT_SYMBOL(ppp_unit_number
);
3285 EXPORT_SYMBOL(ppp_dev_name
);
3286 EXPORT_SYMBOL(ppp_input
);
3287 EXPORT_SYMBOL(ppp_input_error
);
3288 EXPORT_SYMBOL(ppp_output_wakeup
);
3289 EXPORT_SYMBOL(ppp_register_compressor
);
3290 EXPORT_SYMBOL(ppp_unregister_compressor
);
3291 MODULE_LICENSE("GPL");
3292 MODULE_ALIAS_CHARDEV(PPP_MAJOR
, 0);
3293 MODULE_ALIAS_RTNL_LINK("ppp");
3294 MODULE_ALIAS("devname:ppp");