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 <linux/file.h>
50 #include <asm/unaligned.h>
51 #include <net/slhc_vj.h>
52 #include <linux/atomic.h>
54 #include <linux/nsproxy.h>
55 #include <net/net_namespace.h>
56 #include <net/netns/generic.h>
58 #define PPP_VERSION "2.4.2"
61 * Network protocols we support.
63 #define NP_IP 0 /* Internet Protocol V4 */
64 #define NP_IPV6 1 /* Internet Protocol V6 */
65 #define NP_IPX 2 /* IPX protocol */
66 #define NP_AT 3 /* Appletalk protocol */
67 #define NP_MPLS_UC 4 /* MPLS unicast */
68 #define NP_MPLS_MC 5 /* MPLS multicast */
69 #define NUM_NP 6 /* Number of NPs. */
71 #define MPHDRLEN 6 /* multilink protocol header length */
72 #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */
75 * An instance of /dev/ppp can be associated with either a ppp
76 * interface unit or a ppp channel. In both cases, file->private_data
77 * points to one of these.
83 struct sk_buff_head xq; /* pppd transmit queue */
84 struct sk_buff_head rq; /* receive queue for pppd */
85 wait_queue_head_t rwait; /* for poll on reading /dev/ppp */
86 atomic_t refcnt; /* # refs (incl /dev/ppp attached) */
87 int hdrlen; /* space to leave for headers */
88 int index; /* interface unit / channel number */
89 int dead; /* unit/channel has been shut down */
92 #define PF_TO_X(pf, X) container_of(pf, X, file)
94 #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp)
95 #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel)
98 * Data structure to hold primary network stats for which
99 * we want to use 64 bit storage. Other network stats
100 * are stored in dev->stats of the ppp strucute.
102 struct ppp_link_stats {
110 * Data structure describing one ppp unit.
111 * A ppp unit corresponds to a ppp network interface device
112 * and represents a multilink bundle.
113 * It can have 0 or more ppp channels connected to it.
116 struct ppp_file file; /* stuff for read/write/poll 0 */
117 struct file *owner; /* file that owns this unit 48 */
118 struct list_head channels; /* list of attached channels 4c */
119 int n_channels; /* how many channels are attached 54 */
120 spinlock_t rlock; /* lock for receive side 58 */
121 spinlock_t wlock; /* lock for transmit side 5c */
122 int mru; /* max receive unit 60 */
123 unsigned int flags; /* control bits 64 */
124 unsigned int xstate; /* transmit state bits 68 */
125 unsigned int rstate; /* receive state bits 6c */
126 int debug; /* debug flags 70 */
127 struct slcompress *vj; /* state for VJ header compression */
128 enum NPmode npmode[NUM_NP]; /* what to do with each net proto 78 */
129 struct sk_buff *xmit_pending; /* a packet ready to go out 88 */
130 struct compressor *xcomp; /* transmit packet compressor 8c */
131 void *xc_state; /* its internal state 90 */
132 struct compressor *rcomp; /* receive decompressor 94 */
133 void *rc_state; /* its internal state 98 */
134 unsigned long last_xmit; /* jiffies when last pkt sent 9c */
135 unsigned long last_recv; /* jiffies when last pkt rcvd a0 */
136 struct net_device *dev; /* network interface device a4 */
137 int closing; /* is device closing down? a8 */
138 #ifdef CONFIG_PPP_MULTILINK
139 int nxchan; /* next channel to send something on */
140 u32 nxseq; /* next sequence number to send */
141 int mrru; /* MP: max reconst. receive unit */
142 u32 nextseq; /* MP: seq no of next packet */
143 u32 minseq; /* MP: min of most recent seqnos */
144 struct sk_buff_head mrq; /* MP: receive reconstruction queue */
145 #endif /* CONFIG_PPP_MULTILINK */
146 #ifdef CONFIG_PPP_FILTER
147 struct bpf_prog *pass_filter; /* filter for packets to pass */
148 struct bpf_prog *active_filter; /* filter for pkts to reset idle */
149 #endif /* CONFIG_PPP_FILTER */
150 struct net *ppp_net; /* the net we belong to */
151 struct ppp_link_stats stats64; /* 64 bit network stats */
155 * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
156 * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP,
158 * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR.
159 * Bits in xstate: SC_COMP_RUN
161 #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \
162 |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \
163 |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP)
166 * Private data structure for each channel.
167 * This includes the data structure used for multilink.
170 struct ppp_file file; /* stuff for read/write/poll */
171 struct list_head list; /* link in all/new_channels list */
172 struct ppp_channel *chan; /* public channel data structure */
173 struct rw_semaphore chan_sem; /* protects `chan' during chan ioctl */
174 spinlock_t downl; /* protects `chan', file.xq dequeue */
175 struct ppp *ppp; /* ppp unit we're connected to */
176 struct net *chan_net; /* the net channel belongs to */
177 struct list_head clist; /* link in list of channels per unit */
178 rwlock_t upl; /* protects `ppp' */
179 #ifdef CONFIG_PPP_MULTILINK
180 u8 avail; /* flag used in multilink stuff */
181 u8 had_frag; /* >= 1 fragments have been sent */
182 u32 lastseq; /* MP: last sequence # received */
183 int speed; /* speed of the corresponding ppp channel*/
184 #endif /* CONFIG_PPP_MULTILINK */
194 * SMP locking issues:
195 * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels
196 * list and the ppp.n_channels field, you need to take both locks
197 * before you modify them.
198 * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
202 static DEFINE_MUTEX(ppp_mutex);
203 static atomic_t ppp_unit_count = ATOMIC_INIT(0);
204 static atomic_t channel_count = ATOMIC_INIT(0);
206 /* per-net private data for this module */
207 static unsigned int ppp_net_id __read_mostly;
209 /* units to ppp mapping */
210 struct idr units_idr;
213 * all_ppp_mutex protects the units_idr mapping.
214 * It also ensures that finding a ppp unit in the units_idr
215 * map and updating its file.refcnt field is atomic.
217 struct mutex all_ppp_mutex;
220 struct list_head all_channels;
221 struct list_head new_channels;
222 int last_channel_index;
225 * all_channels_lock protects all_channels and
226 * last_channel_index, and the atomicity of find
227 * a channel and updating its file.refcnt field.
229 spinlock_t all_channels_lock;
232 /* Get the PPP protocol number from a skb */
233 #define PPP_PROTO(skb) get_unaligned_be16((skb)->data)
235 /* We limit the length of ppp->file.rq to this (arbitrary) value */
236 #define PPP_MAX_RQLEN 32
239 * Maximum number of multilink fragments queued up.
240 * This has to be large enough to cope with the maximum latency of
241 * the slowest channel relative to the others. Strictly it should
242 * depend on the number of channels and their characteristics.
244 #define PPP_MP_MAX_QLEN 128
246 /* Multilink header bits. */
247 #define B 0x80 /* this fragment begins a packet */
248 #define E 0x40 /* this fragment ends a packet */
250 /* Compare multilink sequence numbers (assumed to be 32 bits wide) */
251 #define seq_before(a, b) ((s32)((a) - (b)) < 0)
252 #define seq_after(a, b) ((s32)((a) - (b)) > 0)
255 static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
256 struct file *file, unsigned int cmd, unsigned long arg);
257 static void ppp_xmit_process(struct ppp *ppp);
258 static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb);
259 static void ppp_push(struct ppp *ppp);
260 static void ppp_channel_push(struct channel *pch);
261 static void ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb,
262 struct channel *pch);
263 static void ppp_receive_error(struct ppp *ppp);
264 static void ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb);
265 static struct sk_buff *ppp_decompress_frame(struct ppp *ppp,
266 struct sk_buff *skb);
267 #ifdef CONFIG_PPP_MULTILINK
268 static void ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb,
269 struct channel *pch);
270 static void ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb);
271 static struct sk_buff *ppp_mp_reconstruct(struct ppp *ppp);
272 static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb);
273 #endif /* CONFIG_PPP_MULTILINK */
274 static int ppp_set_compress(struct ppp *ppp, unsigned long arg);
275 static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound);
276 static void ppp_ccp_closed(struct ppp *ppp);
277 static struct compressor *find_compressor(int type);
278 static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st);
279 static int ppp_create_interface(struct net *net, struct file *file, int *unit);
280 static void init_ppp_file(struct ppp_file *pf, int kind);
281 static void ppp_destroy_interface(struct ppp *ppp);
282 static struct ppp *ppp_find_unit(struct ppp_net *pn, int unit);
283 static struct channel *ppp_find_channel(struct ppp_net *pn, int unit);
284 static int ppp_connect_channel(struct channel *pch, int unit);
285 static int ppp_disconnect_channel(struct channel *pch);
286 static void ppp_destroy_channel(struct channel *pch);
287 static int unit_get(struct idr *p, void *ptr);
288 static int unit_set(struct idr *p, void *ptr, int n);
289 static void unit_put(struct idr *p, int n);
290 static void *unit_find(struct idr *p, int n);
291 static void ppp_setup(struct net_device *dev);
293 static const struct net_device_ops ppp_netdev_ops;
295 static struct class *ppp_class;
297 /* per net-namespace data */
298 static inline struct ppp_net *ppp_pernet(struct net *net)
302 return net_generic(net, ppp_net_id);
305 /* Translates a PPP protocol number to a NP index (NP == network protocol) */
306 static inline int proto_to_npindex(int proto)
325 /* Translates an NP index into a PPP protocol number */
326 static const int npindex_to_proto[NUM_NP] = {
335 /* Translates an ethertype into an NP index */
336 static inline int ethertype_to_npindex(int ethertype)
356 /* Translates an NP index into an ethertype */
357 static const int npindex_to_ethertype[NUM_NP] = {
369 #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock)
370 #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock)
371 #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock)
372 #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock)
373 #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \
374 ppp_recv_lock(ppp); } while (0)
375 #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \
376 ppp_xmit_unlock(ppp); } while (0)
379 * /dev/ppp device routines.
380 * The /dev/ppp device is used by pppd to control the ppp unit.
381 * It supports the read, write, ioctl and poll functions.
382 * Open instances of /dev/ppp can be in one of three states:
383 * unattached, attached to a ppp unit, or attached to a ppp channel.
385 static int ppp_open(struct inode *inode, struct file *file)
388 * This could (should?) be enforced by the permissions on /dev/ppp.
390 if (!capable(CAP_NET_ADMIN))
395 static int ppp_release(struct inode *unused, struct file *file)
397 struct ppp_file *pf = file->private_data;
401 file->private_data = NULL;
402 if (pf->kind == INTERFACE) {
405 if (file == ppp->owner)
406 unregister_netdevice(ppp->dev);
409 if (atomic_dec_and_test(&pf->refcnt)) {
412 ppp_destroy_interface(PF_TO_PPP(pf));
415 ppp_destroy_channel(PF_TO_CHANNEL(pf));
423 static ssize_t ppp_read(struct file *file, char __user *buf,
424 size_t count, loff_t *ppos)
426 struct ppp_file *pf = file->private_data;
427 DECLARE_WAITQUEUE(wait, current);
429 struct sk_buff *skb = NULL;
437 add_wait_queue(&pf->rwait, &wait);
439 set_current_state(TASK_INTERRUPTIBLE);
440 skb = skb_dequeue(&pf->rq);
446 if (pf->kind == INTERFACE) {
448 * Return 0 (EOF) on an interface that has no
449 * channels connected, unless it is looping
450 * network traffic (demand mode).
452 struct ppp *ppp = PF_TO_PPP(pf);
455 if (ppp->n_channels == 0 &&
456 (ppp->flags & SC_LOOP_TRAFFIC) == 0) {
457 ppp_recv_unlock(ppp);
460 ppp_recv_unlock(ppp);
463 if (file->f_flags & O_NONBLOCK)
466 if (signal_pending(current))
470 set_current_state(TASK_RUNNING);
471 remove_wait_queue(&pf->rwait, &wait);
477 if (skb->len > count)
482 iov_iter_init(&to, READ, &iov, 1, count);
483 if (skb_copy_datagram_iter(skb, 0, &to, skb->len))
493 static ssize_t ppp_write(struct file *file, const char __user *buf,
494 size_t count, loff_t *ppos)
496 struct ppp_file *pf = file->private_data;
503 skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL);
506 skb_reserve(skb, pf->hdrlen);
508 if (copy_from_user(skb_put(skb, count), buf, count)) {
513 skb_queue_tail(&pf->xq, skb);
517 ppp_xmit_process(PF_TO_PPP(pf));
520 ppp_channel_push(PF_TO_CHANNEL(pf));
530 /* No kernel lock - fine */
531 static unsigned int ppp_poll(struct file *file, poll_table *wait)
533 struct ppp_file *pf = file->private_data;
538 poll_wait(file, &pf->rwait, wait);
539 mask = POLLOUT | POLLWRNORM;
540 if (skb_peek(&pf->rq))
541 mask |= POLLIN | POLLRDNORM;
544 else if (pf->kind == INTERFACE) {
545 /* see comment in ppp_read */
546 struct ppp *ppp = PF_TO_PPP(pf);
549 if (ppp->n_channels == 0 &&
550 (ppp->flags & SC_LOOP_TRAFFIC) == 0)
551 mask |= POLLIN | POLLRDNORM;
552 ppp_recv_unlock(ppp);
558 #ifdef CONFIG_PPP_FILTER
559 static int get_filter(void __user *arg, struct sock_filter **p)
561 struct sock_fprog uprog;
562 struct sock_filter *code = NULL;
565 if (copy_from_user(&uprog, arg, sizeof(uprog)))
573 len = uprog.len * sizeof(struct sock_filter);
574 code = memdup_user(uprog.filter, len);
576 return PTR_ERR(code);
581 #endif /* CONFIG_PPP_FILTER */
583 static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
587 int err = -EFAULT, val, val2, i;
588 struct ppp_idle idle;
591 struct slcompress *vj;
592 void __user *argp = (void __user *)arg;
593 int __user *p = argp;
595 mutex_lock(&ppp_mutex);
597 pf = file->private_data;
599 err = ppp_unattached_ioctl(current->nsproxy->net_ns,
604 if (cmd == PPPIOCDETACH) {
606 * We have to be careful here... if the file descriptor
607 * has been dup'd, we could have another process in the
608 * middle of a poll using the same file *, so we had
609 * better not free the interface data structures -
610 * instead we fail the ioctl. Even in this case, we
611 * shut down the interface if we are the owner of it.
612 * Actually, we should get rid of PPPIOCDETACH, userland
613 * (i.e. pppd) could achieve the same effect by closing
614 * this fd and reopening /dev/ppp.
617 if (pf->kind == INTERFACE) {
620 if (file == ppp->owner)
621 unregister_netdevice(ppp->dev);
624 if (atomic_long_read(&file->f_count) < 2) {
625 ppp_release(NULL, file);
628 pr_warn("PPPIOCDETACH file->f_count=%ld\n",
629 atomic_long_read(&file->f_count));
633 if (pf->kind == CHANNEL) {
635 struct ppp_channel *chan;
637 pch = PF_TO_CHANNEL(pf);
641 if (get_user(unit, p))
643 err = ppp_connect_channel(pch, unit);
647 err = ppp_disconnect_channel(pch);
651 down_read(&pch->chan_sem);
654 if (chan && chan->ops->ioctl)
655 err = chan->ops->ioctl(chan, cmd, arg);
656 up_read(&pch->chan_sem);
661 if (pf->kind != INTERFACE) {
663 pr_err("PPP: not interface or channel??\n");
671 if (get_user(val, p))
678 if (get_user(val, p))
681 cflags = ppp->flags & ~val;
682 #ifdef CONFIG_PPP_MULTILINK
683 if (!(ppp->flags & SC_MULTILINK) && (val & SC_MULTILINK))
686 ppp->flags = val & SC_FLAG_BITS;
688 if (cflags & SC_CCP_OPEN)
694 val = ppp->flags | ppp->xstate | ppp->rstate;
695 if (put_user(val, p))
700 case PPPIOCSCOMPRESS:
701 err = ppp_set_compress(ppp, arg);
705 if (put_user(ppp->file.index, p))
711 if (get_user(val, p))
718 if (put_user(ppp->debug, p))
724 idle.xmit_idle = (jiffies - ppp->last_xmit) / HZ;
725 idle.recv_idle = (jiffies - ppp->last_recv) / HZ;
726 if (copy_to_user(argp, &idle, sizeof(idle)))
732 if (get_user(val, p))
735 if ((val >> 16) != 0) {
739 vj = slhc_init(val2+1, val+1);
754 if (copy_from_user(&npi, argp, sizeof(npi)))
756 err = proto_to_npindex(npi.protocol);
760 if (cmd == PPPIOCGNPMODE) {
762 npi.mode = ppp->npmode[i];
763 if (copy_to_user(argp, &npi, sizeof(npi)))
766 ppp->npmode[i] = npi.mode;
767 /* we may be able to transmit more packets now (??) */
768 netif_wake_queue(ppp->dev);
773 #ifdef CONFIG_PPP_FILTER
776 struct sock_filter *code;
778 err = get_filter(argp, &code);
780 struct bpf_prog *pass_filter = NULL;
781 struct sock_fprog_kern fprog = {
788 err = bpf_prog_create(&pass_filter, &fprog);
791 if (ppp->pass_filter)
792 bpf_prog_destroy(ppp->pass_filter);
793 ppp->pass_filter = pass_filter;
802 struct sock_filter *code;
804 err = get_filter(argp, &code);
806 struct bpf_prog *active_filter = NULL;
807 struct sock_fprog_kern fprog = {
814 err = bpf_prog_create(&active_filter, &fprog);
817 if (ppp->active_filter)
818 bpf_prog_destroy(ppp->active_filter);
819 ppp->active_filter = active_filter;
826 #endif /* CONFIG_PPP_FILTER */
828 #ifdef CONFIG_PPP_MULTILINK
830 if (get_user(val, p))
834 ppp_recv_unlock(ppp);
837 #endif /* CONFIG_PPP_MULTILINK */
844 mutex_unlock(&ppp_mutex);
849 static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
850 struct file *file, unsigned int cmd, unsigned long arg)
852 int unit, err = -EFAULT;
854 struct channel *chan;
856 int __user *p = (int __user *)arg;
860 /* Create a new ppp unit */
861 if (get_user(unit, p))
863 err = ppp_create_interface(net, file, &unit);
868 if (put_user(unit, p))
874 /* Attach to an existing ppp unit */
875 if (get_user(unit, p))
878 pn = ppp_pernet(net);
879 mutex_lock(&pn->all_ppp_mutex);
880 ppp = ppp_find_unit(pn, unit);
882 atomic_inc(&ppp->file.refcnt);
883 file->private_data = &ppp->file;
886 mutex_unlock(&pn->all_ppp_mutex);
890 if (get_user(unit, p))
893 pn = ppp_pernet(net);
894 spin_lock_bh(&pn->all_channels_lock);
895 chan = ppp_find_channel(pn, unit);
897 atomic_inc(&chan->file.refcnt);
898 file->private_data = &chan->file;
901 spin_unlock_bh(&pn->all_channels_lock);
911 static const struct file_operations ppp_device_fops = {
912 .owner = THIS_MODULE,
916 .unlocked_ioctl = ppp_ioctl,
918 .release = ppp_release,
919 .llseek = noop_llseek,
922 static __net_init int ppp_init_net(struct net *net)
924 struct ppp_net *pn = net_generic(net, ppp_net_id);
926 idr_init(&pn->units_idr);
927 mutex_init(&pn->all_ppp_mutex);
929 INIT_LIST_HEAD(&pn->all_channels);
930 INIT_LIST_HEAD(&pn->new_channels);
932 spin_lock_init(&pn->all_channels_lock);
937 static __net_exit void ppp_exit_net(struct net *net)
939 struct ppp_net *pn = net_generic(net, ppp_net_id);
940 struct net_device *dev;
941 struct net_device *aux;
947 for_each_netdev_safe(net, dev, aux) {
948 if (dev->netdev_ops == &ppp_netdev_ops)
949 unregister_netdevice_queue(dev, &list);
952 idr_for_each_entry(&pn->units_idr, ppp, id)
953 /* Skip devices already unregistered by previous loop */
954 if (!net_eq(dev_net(ppp->dev), net))
955 unregister_netdevice_queue(ppp->dev, &list);
957 unregister_netdevice_many(&list);
960 idr_destroy(&pn->units_idr);
963 static struct pernet_operations ppp_net_ops = {
964 .init = ppp_init_net,
965 .exit = ppp_exit_net,
967 .size = sizeof(struct ppp_net),
970 static int ppp_unit_register(struct ppp *ppp, int unit, bool ifname_is_set)
972 struct ppp_net *pn = ppp_pernet(ppp->ppp_net);
975 mutex_lock(&pn->all_ppp_mutex);
978 ret = unit_get(&pn->units_idr, ppp);
982 /* Caller asked for a specific unit number. Fail with -EEXIST
983 * if unavailable. For backward compatibility, return -EEXIST
984 * too if idr allocation fails; this makes pppd retry without
985 * requesting a specific unit number.
987 if (unit_find(&pn->units_idr, unit)) {
991 ret = unit_set(&pn->units_idr, ppp, unit);
993 /* Rewrite error for backward compatibility */
998 ppp->file.index = ret;
1001 snprintf(ppp->dev->name, IFNAMSIZ, "ppp%i", ppp->file.index);
1003 ret = register_netdevice(ppp->dev);
1007 atomic_inc(&ppp_unit_count);
1009 mutex_unlock(&pn->all_ppp_mutex);
1014 unit_put(&pn->units_idr, ppp->file.index);
1016 mutex_unlock(&pn->all_ppp_mutex);
1021 static int ppp_dev_configure(struct net *src_net, struct net_device *dev,
1022 const struct ppp_config *conf)
1024 struct ppp *ppp = netdev_priv(dev);
1029 ppp->ppp_net = src_net;
1031 ppp->owner = conf->file;
1033 init_ppp_file(&ppp->file, INTERFACE);
1034 ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */
1036 for (indx = 0; indx < NUM_NP; ++indx)
1037 ppp->npmode[indx] = NPMODE_PASS;
1038 INIT_LIST_HEAD(&ppp->channels);
1039 spin_lock_init(&ppp->rlock);
1040 spin_lock_init(&ppp->wlock);
1041 #ifdef CONFIG_PPP_MULTILINK
1043 skb_queue_head_init(&ppp->mrq);
1044 #endif /* CONFIG_PPP_MULTILINK */
1045 #ifdef CONFIG_PPP_FILTER
1046 ppp->pass_filter = NULL;
1047 ppp->active_filter = NULL;
1048 #endif /* CONFIG_PPP_FILTER */
1050 err = ppp_unit_register(ppp, conf->unit, conf->ifname_is_set);
1054 conf->file->private_data = &ppp->file;
1059 static const struct nla_policy ppp_nl_policy[IFLA_PPP_MAX + 1] = {
1060 [IFLA_PPP_DEV_FD] = { .type = NLA_S32 },
1063 static int ppp_nl_validate(struct nlattr *tb[], struct nlattr *data[])
1068 if (!data[IFLA_PPP_DEV_FD])
1070 if (nla_get_s32(data[IFLA_PPP_DEV_FD]) < 0)
1076 static int ppp_nl_newlink(struct net *src_net, struct net_device *dev,
1077 struct nlattr *tb[], struct nlattr *data[])
1079 struct ppp_config conf = {
1081 .ifname_is_set = true,
1086 file = fget(nla_get_s32(data[IFLA_PPP_DEV_FD]));
1090 /* rtnl_lock is already held here, but ppp_create_interface() locks
1091 * ppp_mutex before holding rtnl_lock. Using mutex_trylock() avoids
1092 * possible deadlock due to lock order inversion, at the cost of
1093 * pushing the problem back to userspace.
1095 if (!mutex_trylock(&ppp_mutex)) {
1100 if (file->f_op != &ppp_device_fops || file->private_data) {
1107 /* Don't use device name generated by the rtnetlink layer when ifname
1108 * isn't specified. Let ppp_dev_configure() set the device name using
1109 * the PPP unit identifer as suffix (i.e. ppp<unit_id>). This allows
1110 * userspace to infer the device name using to the PPPIOCGUNIT ioctl.
1112 if (!tb[IFLA_IFNAME])
1113 conf.ifname_is_set = false;
1115 err = ppp_dev_configure(src_net, dev, &conf);
1118 mutex_unlock(&ppp_mutex);
1125 static void ppp_nl_dellink(struct net_device *dev, struct list_head *head)
1127 unregister_netdevice_queue(dev, head);
1130 static size_t ppp_nl_get_size(const struct net_device *dev)
1135 static int ppp_nl_fill_info(struct sk_buff *skb, const struct net_device *dev)
1140 static struct net *ppp_nl_get_link_net(const struct net_device *dev)
1142 struct ppp *ppp = netdev_priv(dev);
1144 return ppp->ppp_net;
1147 static struct rtnl_link_ops ppp_link_ops __read_mostly = {
1149 .maxtype = IFLA_PPP_MAX,
1150 .policy = ppp_nl_policy,
1151 .priv_size = sizeof(struct ppp),
1153 .validate = ppp_nl_validate,
1154 .newlink = ppp_nl_newlink,
1155 .dellink = ppp_nl_dellink,
1156 .get_size = ppp_nl_get_size,
1157 .fill_info = ppp_nl_fill_info,
1158 .get_link_net = ppp_nl_get_link_net,
1161 #define PPP_MAJOR 108
1163 /* Called at boot time if ppp is compiled into the kernel,
1164 or at module load time (from init_module) if compiled as a module. */
1165 static int __init ppp_init(void)
1169 pr_info("PPP generic driver version " PPP_VERSION "\n");
1171 err = register_pernet_device(&ppp_net_ops);
1173 pr_err("failed to register PPP pernet device (%d)\n", err);
1177 err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops);
1179 pr_err("failed to register PPP device (%d)\n", err);
1183 ppp_class = class_create(THIS_MODULE, "ppp");
1184 if (IS_ERR(ppp_class)) {
1185 err = PTR_ERR(ppp_class);
1189 err = rtnl_link_register(&ppp_link_ops);
1191 pr_err("failed to register rtnetlink PPP handler\n");
1195 /* not a big deal if we fail here :-) */
1196 device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, "ppp");
1201 class_destroy(ppp_class);
1203 unregister_chrdev(PPP_MAJOR, "ppp");
1205 unregister_pernet_device(&ppp_net_ops);
1211 * Network interface unit routines.
1214 ppp_start_xmit(struct sk_buff *skb, struct net_device *dev)
1216 struct ppp *ppp = netdev_priv(dev);
1220 npi = ethertype_to_npindex(ntohs(skb->protocol));
1224 /* Drop, accept or reject the packet */
1225 switch (ppp->npmode[npi]) {
1229 /* it would be nice to have a way to tell the network
1230 system to queue this one up for later. */
1237 /* Put the 2-byte PPP protocol number on the front,
1238 making sure there is room for the address and control fields. */
1239 if (skb_cow_head(skb, PPP_HDRLEN))
1242 pp = skb_push(skb, 2);
1243 proto = npindex_to_proto[npi];
1244 put_unaligned_be16(proto, pp);
1246 skb_scrub_packet(skb, !net_eq(ppp->ppp_net, dev_net(dev)));
1247 skb_queue_tail(&ppp->file.xq, skb);
1248 ppp_xmit_process(ppp);
1249 return NETDEV_TX_OK;
1253 ++dev->stats.tx_dropped;
1254 return NETDEV_TX_OK;
1258 ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1260 struct ppp *ppp = netdev_priv(dev);
1262 void __user *addr = (void __user *) ifr->ifr_ifru.ifru_data;
1263 struct ppp_stats stats;
1264 struct ppp_comp_stats cstats;
1269 ppp_get_stats(ppp, &stats);
1270 if (copy_to_user(addr, &stats, sizeof(stats)))
1275 case SIOCGPPPCSTATS:
1276 memset(&cstats, 0, sizeof(cstats));
1278 ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c);
1280 ppp->rcomp->decomp_stat(ppp->rc_state, &cstats.d);
1281 if (copy_to_user(addr, &cstats, sizeof(cstats)))
1288 if (copy_to_user(addr, vers, strlen(vers) + 1))
1301 ppp_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats64)
1303 struct ppp *ppp = netdev_priv(dev);
1306 stats64->rx_packets = ppp->stats64.rx_packets;
1307 stats64->rx_bytes = ppp->stats64.rx_bytes;
1308 ppp_recv_unlock(ppp);
1311 stats64->tx_packets = ppp->stats64.tx_packets;
1312 stats64->tx_bytes = ppp->stats64.tx_bytes;
1313 ppp_xmit_unlock(ppp);
1315 stats64->rx_errors = dev->stats.rx_errors;
1316 stats64->tx_errors = dev->stats.tx_errors;
1317 stats64->rx_dropped = dev->stats.rx_dropped;
1318 stats64->tx_dropped = dev->stats.tx_dropped;
1319 stats64->rx_length_errors = dev->stats.rx_length_errors;
1322 static int ppp_dev_init(struct net_device *dev)
1324 netdev_lockdep_set_classes(dev);
1328 static void ppp_dev_uninit(struct net_device *dev)
1330 struct ppp *ppp = netdev_priv(dev);
1331 struct ppp_net *pn = ppp_pernet(ppp->ppp_net);
1337 mutex_lock(&pn->all_ppp_mutex);
1338 unit_put(&pn->units_idr, ppp->file.index);
1339 mutex_unlock(&pn->all_ppp_mutex);
1344 wake_up_interruptible(&ppp->file.rwait);
1347 static const struct net_device_ops ppp_netdev_ops = {
1348 .ndo_init = ppp_dev_init,
1349 .ndo_uninit = ppp_dev_uninit,
1350 .ndo_start_xmit = ppp_start_xmit,
1351 .ndo_do_ioctl = ppp_net_ioctl,
1352 .ndo_get_stats64 = ppp_get_stats64,
1355 static struct device_type ppp_type = {
1359 static void ppp_setup(struct net_device *dev)
1361 dev->netdev_ops = &ppp_netdev_ops;
1362 SET_NETDEV_DEVTYPE(dev, &ppp_type);
1364 dev->features |= NETIF_F_LLTX;
1366 dev->hard_header_len = PPP_HDRLEN;
1369 dev->tx_queue_len = 3;
1370 dev->type = ARPHRD_PPP;
1371 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
1372 netif_keep_dst(dev);
1376 * Transmit-side routines.
1379 /* Called to do any work queued up on the transmit side that can now be done */
1380 static void __ppp_xmit_process(struct ppp *ppp)
1382 struct sk_buff *skb;
1385 if (!ppp->closing) {
1387 while (!ppp->xmit_pending &&
1388 (skb = skb_dequeue(&ppp->file.xq)))
1389 ppp_send_frame(ppp, skb);
1390 /* If there's no work left to do, tell the core net
1391 code that we can accept some more. */
1392 if (!ppp->xmit_pending && !skb_peek(&ppp->file.xq))
1393 netif_wake_queue(ppp->dev);
1395 netif_stop_queue(ppp->dev);
1397 ppp_xmit_unlock(ppp);
1400 static DEFINE_PER_CPU(int, ppp_xmit_recursion);
1402 static void ppp_xmit_process(struct ppp *ppp)
1406 if (unlikely(__this_cpu_read(ppp_xmit_recursion)))
1409 __this_cpu_inc(ppp_xmit_recursion);
1410 __ppp_xmit_process(ppp);
1411 __this_cpu_dec(ppp_xmit_recursion);
1420 if (net_ratelimit())
1421 netdev_err(ppp->dev, "recursion detected\n");
1424 static inline struct sk_buff *
1425 pad_compress_skb(struct ppp *ppp, struct sk_buff *skb)
1427 struct sk_buff *new_skb;
1429 int new_skb_size = ppp->dev->mtu +
1430 ppp->xcomp->comp_extra + ppp->dev->hard_header_len;
1431 int compressor_skb_size = ppp->dev->mtu +
1432 ppp->xcomp->comp_extra + PPP_HDRLEN;
1433 new_skb = alloc_skb(new_skb_size, GFP_ATOMIC);
1435 if (net_ratelimit())
1436 netdev_err(ppp->dev, "PPP: no memory (comp pkt)\n");
1439 if (ppp->dev->hard_header_len > PPP_HDRLEN)
1440 skb_reserve(new_skb,
1441 ppp->dev->hard_header_len - PPP_HDRLEN);
1443 /* compressor still expects A/C bytes in hdr */
1444 len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2,
1445 new_skb->data, skb->len + 2,
1446 compressor_skb_size);
1447 if (len > 0 && (ppp->flags & SC_CCP_UP)) {
1451 skb_pull(skb, 2); /* pull off A/C bytes */
1452 } else if (len == 0) {
1453 /* didn't compress, or CCP not up yet */
1454 consume_skb(new_skb);
1459 * MPPE requires that we do not send unencrypted
1460 * frames. The compressor will return -1 if we
1461 * should drop the frame. We cannot simply test
1462 * the compress_proto because MPPE and MPPC share
1465 if (net_ratelimit())
1466 netdev_err(ppp->dev, "ppp: compressor dropped pkt\n");
1468 consume_skb(new_skb);
1475 * Compress and send a frame.
1476 * The caller should have locked the xmit path,
1477 * and xmit_pending should be 0.
1480 ppp_send_frame(struct ppp *ppp, struct sk_buff *skb)
1482 int proto = PPP_PROTO(skb);
1483 struct sk_buff *new_skb;
1487 if (proto < 0x8000) {
1488 #ifdef CONFIG_PPP_FILTER
1489 /* check if we should pass this packet */
1490 /* the filter instructions are constructed assuming
1491 a four-byte PPP header on each packet */
1492 *skb_push(skb, 2) = 1;
1493 if (ppp->pass_filter &&
1494 BPF_PROG_RUN(ppp->pass_filter, skb) == 0) {
1496 netdev_printk(KERN_DEBUG, ppp->dev,
1497 "PPP: outbound frame "
1502 /* if this packet passes the active filter, record the time */
1503 if (!(ppp->active_filter &&
1504 BPF_PROG_RUN(ppp->active_filter, skb) == 0))
1505 ppp->last_xmit = jiffies;
1508 /* for data packets, record the time */
1509 ppp->last_xmit = jiffies;
1510 #endif /* CONFIG_PPP_FILTER */
1513 ++ppp->stats64.tx_packets;
1514 ppp->stats64.tx_bytes += skb->len - 2;
1518 if (!ppp->vj || (ppp->flags & SC_COMP_TCP) == 0)
1520 /* try to do VJ TCP header compression */
1521 new_skb = alloc_skb(skb->len + ppp->dev->hard_header_len - 2,
1524 netdev_err(ppp->dev, "PPP: no memory (VJ comp pkt)\n");
1527 skb_reserve(new_skb, ppp->dev->hard_header_len - 2);
1529 len = slhc_compress(ppp->vj, cp, skb->len - 2,
1530 new_skb->data + 2, &cp,
1531 !(ppp->flags & SC_NO_TCP_CCID));
1532 if (cp == skb->data + 2) {
1533 /* didn't compress */
1534 consume_skb(new_skb);
1536 if (cp[0] & SL_TYPE_COMPRESSED_TCP) {
1537 proto = PPP_VJC_COMP;
1538 cp[0] &= ~SL_TYPE_COMPRESSED_TCP;
1540 proto = PPP_VJC_UNCOMP;
1541 cp[0] = skb->data[2];
1545 cp = skb_put(skb, len + 2);
1552 /* peek at outbound CCP frames */
1553 ppp_ccp_peek(ppp, skb, 0);
1557 /* try to do packet compression */
1558 if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state &&
1559 proto != PPP_LCP && proto != PPP_CCP) {
1560 if (!(ppp->flags & SC_CCP_UP) && (ppp->flags & SC_MUST_COMP)) {
1561 if (net_ratelimit())
1562 netdev_err(ppp->dev,
1563 "ppp: compression required but "
1564 "down - pkt dropped.\n");
1567 skb = pad_compress_skb(ppp, skb);
1573 * If we are waiting for traffic (demand dialling),
1574 * queue it up for pppd to receive.
1576 if (ppp->flags & SC_LOOP_TRAFFIC) {
1577 if (ppp->file.rq.qlen > PPP_MAX_RQLEN)
1579 skb_queue_tail(&ppp->file.rq, skb);
1580 wake_up_interruptible(&ppp->file.rwait);
1584 ppp->xmit_pending = skb;
1590 ++ppp->dev->stats.tx_errors;
1594 * Try to send the frame in xmit_pending.
1595 * The caller should have the xmit path locked.
1598 ppp_push(struct ppp *ppp)
1600 struct list_head *list;
1601 struct channel *pch;
1602 struct sk_buff *skb = ppp->xmit_pending;
1607 list = &ppp->channels;
1608 if (list_empty(list)) {
1609 /* nowhere to send the packet, just drop it */
1610 ppp->xmit_pending = NULL;
1615 if ((ppp->flags & SC_MULTILINK) == 0) {
1616 /* not doing multilink: send it down the first channel */
1618 pch = list_entry(list, struct channel, clist);
1620 spin_lock_bh(&pch->downl);
1622 if (pch->chan->ops->start_xmit(pch->chan, skb))
1623 ppp->xmit_pending = NULL;
1625 /* channel got unregistered */
1627 ppp->xmit_pending = NULL;
1629 spin_unlock_bh(&pch->downl);
1633 #ifdef CONFIG_PPP_MULTILINK
1634 /* Multilink: fragment the packet over as many links
1635 as can take the packet at the moment. */
1636 if (!ppp_mp_explode(ppp, skb))
1638 #endif /* CONFIG_PPP_MULTILINK */
1640 ppp->xmit_pending = NULL;
1644 #ifdef CONFIG_PPP_MULTILINK
1645 static bool mp_protocol_compress __read_mostly = true;
1646 module_param(mp_protocol_compress, bool, S_IRUGO | S_IWUSR);
1647 MODULE_PARM_DESC(mp_protocol_compress,
1648 "compress protocol id in multilink fragments");
1651 * Divide a packet to be transmitted into fragments and
1652 * send them out the individual links.
1654 static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb)
1657 int i, bits, hdrlen, mtu;
1659 int navail, nfree, nzero;
1663 unsigned char *p, *q;
1664 struct list_head *list;
1665 struct channel *pch;
1666 struct sk_buff *frag;
1667 struct ppp_channel *chan;
1669 totspeed = 0; /*total bitrate of the bundle*/
1670 nfree = 0; /* # channels which have no packet already queued */
1671 navail = 0; /* total # of usable channels (not deregistered) */
1672 nzero = 0; /* number of channels with zero speed associated*/
1673 totfree = 0; /*total # of channels available and
1674 *having no queued packets before
1675 *starting the fragmentation*/
1677 hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
1679 list_for_each_entry(pch, &ppp->channels, clist) {
1683 pch->speed = pch->chan->speed;
1688 if (skb_queue_empty(&pch->file.xq) ||
1690 if (pch->speed == 0)
1693 totspeed += pch->speed;
1699 if (!pch->had_frag && i < ppp->nxchan)
1705 * Don't start sending this packet unless at least half of
1706 * the channels are free. This gives much better TCP
1707 * performance if we have a lot of channels.
1709 if (nfree == 0 || nfree < navail / 2)
1710 return 0; /* can't take now, leave it in xmit_pending */
1712 /* Do protocol field compression */
1715 if (*p == 0 && mp_protocol_compress) {
1721 nbigger = len % nfree;
1723 /* skip to the channel after the one we last used
1724 and start at that one */
1725 list = &ppp->channels;
1726 for (i = 0; i < ppp->nxchan; ++i) {
1728 if (list == &ppp->channels) {
1734 /* create a fragment for each channel */
1738 if (list == &ppp->channels) {
1742 pch = list_entry(list, struct channel, clist);
1748 * Skip this channel if it has a fragment pending already and
1749 * we haven't given a fragment to all of the free channels.
1751 if (pch->avail == 1) {
1758 /* check the channel's mtu and whether it is still attached. */
1759 spin_lock_bh(&pch->downl);
1760 if (pch->chan == NULL) {
1761 /* can't use this channel, it's being deregistered */
1762 if (pch->speed == 0)
1765 totspeed -= pch->speed;
1767 spin_unlock_bh(&pch->downl);
1778 *if the channel speed is not set divide
1779 *the packet evenly among the free channels;
1780 *otherwise divide it according to the speed
1781 *of the channel we are going to transmit on
1785 if (pch->speed == 0) {
1792 flen = (((totfree - nzero)*(totlen + hdrlen*totfree)) /
1793 ((totspeed*totfree)/pch->speed)) - hdrlen;
1795 flen += ((totfree - nzero)*pch->speed)/totspeed;
1796 nbigger -= ((totfree - nzero)*pch->speed)/
1804 *check if we are on the last channel or
1805 *we exceded the length of the data to
1808 if ((nfree <= 0) || (flen > len))
1811 *it is not worth to tx on slow channels:
1812 *in that case from the resulting flen according to the
1813 *above formula will be equal or less than zero.
1814 *Skip the channel in this case
1818 spin_unlock_bh(&pch->downl);
1823 * hdrlen includes the 2-byte PPP protocol field, but the
1824 * MTU counts only the payload excluding the protocol field.
1825 * (RFC1661 Section 2)
1827 mtu = pch->chan->mtu - (hdrlen - 2);
1834 frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
1837 q = skb_put(frag, flen + hdrlen);
1839 /* make the MP header */
1840 put_unaligned_be16(PPP_MP, q);
1841 if (ppp->flags & SC_MP_XSHORTSEQ) {
1842 q[2] = bits + ((ppp->nxseq >> 8) & 0xf);
1846 q[3] = ppp->nxseq >> 16;
1847 q[4] = ppp->nxseq >> 8;
1851 memcpy(q + hdrlen, p, flen);
1853 /* try to send it down the channel */
1855 if (!skb_queue_empty(&pch->file.xq) ||
1856 !chan->ops->start_xmit(chan, frag))
1857 skb_queue_tail(&pch->file.xq, frag);
1863 spin_unlock_bh(&pch->downl);
1870 spin_unlock_bh(&pch->downl);
1872 netdev_err(ppp->dev, "PPP: no memory (fragment)\n");
1873 ++ppp->dev->stats.tx_errors;
1875 return 1; /* abandon the frame */
1877 #endif /* CONFIG_PPP_MULTILINK */
1879 /* Try to send data out on a channel */
1880 static void __ppp_channel_push(struct channel *pch)
1882 struct sk_buff *skb;
1885 spin_lock_bh(&pch->downl);
1887 while (!skb_queue_empty(&pch->file.xq)) {
1888 skb = skb_dequeue(&pch->file.xq);
1889 if (!pch->chan->ops->start_xmit(pch->chan, skb)) {
1890 /* put the packet back and try again later */
1891 skb_queue_head(&pch->file.xq, skb);
1896 /* channel got deregistered */
1897 skb_queue_purge(&pch->file.xq);
1899 spin_unlock_bh(&pch->downl);
1900 /* see if there is anything from the attached unit to be sent */
1901 if (skb_queue_empty(&pch->file.xq)) {
1902 read_lock_bh(&pch->upl);
1905 __ppp_xmit_process(ppp);
1906 read_unlock_bh(&pch->upl);
1910 static void ppp_channel_push(struct channel *pch)
1914 __this_cpu_inc(ppp_xmit_recursion);
1915 __ppp_channel_push(pch);
1916 __this_cpu_dec(ppp_xmit_recursion);
1922 * Receive-side routines.
1925 struct ppp_mp_skb_parm {
1929 #define PPP_MP_CB(skb) ((struct ppp_mp_skb_parm *)((skb)->cb))
1932 ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1936 ppp_receive_frame(ppp, skb, pch);
1939 ppp_recv_unlock(ppp);
1943 ppp_input(struct ppp_channel *chan, struct sk_buff *skb)
1945 struct channel *pch = chan->ppp;
1953 read_lock_bh(&pch->upl);
1954 if (!pskb_may_pull(skb, 2)) {
1957 ++pch->ppp->dev->stats.rx_length_errors;
1958 ppp_receive_error(pch->ppp);
1963 proto = PPP_PROTO(skb);
1964 if (!pch->ppp || proto >= 0xc000 || proto == PPP_CCPFRAG) {
1965 /* put it on the channel queue */
1966 skb_queue_tail(&pch->file.rq, skb);
1967 /* drop old frames if queue too long */
1968 while (pch->file.rq.qlen > PPP_MAX_RQLEN &&
1969 (skb = skb_dequeue(&pch->file.rq)))
1971 wake_up_interruptible(&pch->file.rwait);
1973 ppp_do_recv(pch->ppp, skb, pch);
1977 read_unlock_bh(&pch->upl);
1980 /* Put a 0-length skb in the receive queue as an error indication */
1982 ppp_input_error(struct ppp_channel *chan, int code)
1984 struct channel *pch = chan->ppp;
1985 struct sk_buff *skb;
1990 read_lock_bh(&pch->upl);
1992 skb = alloc_skb(0, GFP_ATOMIC);
1994 skb->len = 0; /* probably unnecessary */
1996 ppp_do_recv(pch->ppp, skb, pch);
1999 read_unlock_bh(&pch->upl);
2003 * We come in here to process a received frame.
2004 * The receive side of the ppp unit is locked.
2007 ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
2009 /* note: a 0-length skb is used as an error indication */
2011 skb_checksum_complete_unset(skb);
2012 #ifdef CONFIG_PPP_MULTILINK
2013 /* XXX do channel-level decompression here */
2014 if (PPP_PROTO(skb) == PPP_MP)
2015 ppp_receive_mp_frame(ppp, skb, pch);
2017 #endif /* CONFIG_PPP_MULTILINK */
2018 ppp_receive_nonmp_frame(ppp, skb);
2021 ppp_receive_error(ppp);
2026 ppp_receive_error(struct ppp *ppp)
2028 ++ppp->dev->stats.rx_errors;
2034 ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb)
2037 int proto, len, npi;
2040 * Decompress the frame, if compressed.
2041 * Note that some decompressors need to see uncompressed frames
2042 * that come in as well as compressed frames.
2044 if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN) &&
2045 (ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0)
2046 skb = ppp_decompress_frame(ppp, skb);
2048 if (ppp->flags & SC_MUST_COMP && ppp->rstate & SC_DC_FERROR)
2051 proto = PPP_PROTO(skb);
2054 /* decompress VJ compressed packets */
2055 if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP))
2058 if (skb_tailroom(skb) < 124 || skb_cloned(skb)) {
2059 /* copy to a new sk_buff with more tailroom */
2060 ns = dev_alloc_skb(skb->len + 128);
2062 netdev_err(ppp->dev, "PPP: no memory "
2067 skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len);
2072 skb->ip_summed = CHECKSUM_NONE;
2074 len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2);
2076 netdev_printk(KERN_DEBUG, ppp->dev,
2077 "PPP: VJ decompression error\n");
2082 skb_put(skb, len - skb->len);
2083 else if (len < skb->len)
2088 case PPP_VJC_UNCOMP:
2089 if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP))
2092 /* Until we fix the decompressor need to make sure
2093 * data portion is linear.
2095 if (!pskb_may_pull(skb, skb->len))
2098 if (slhc_remember(ppp->vj, skb->data + 2, skb->len - 2) <= 0) {
2099 netdev_err(ppp->dev, "PPP: VJ uncompressed error\n");
2106 ppp_ccp_peek(ppp, skb, 1);
2110 ++ppp->stats64.rx_packets;
2111 ppp->stats64.rx_bytes += skb->len - 2;
2113 npi = proto_to_npindex(proto);
2115 /* control or unknown frame - pass it to pppd */
2116 skb_queue_tail(&ppp->file.rq, skb);
2117 /* limit queue length by dropping old frames */
2118 while (ppp->file.rq.qlen > PPP_MAX_RQLEN &&
2119 (skb = skb_dequeue(&ppp->file.rq)))
2121 /* wake up any process polling or blocking on read */
2122 wake_up_interruptible(&ppp->file.rwait);
2125 /* network protocol frame - give it to the kernel */
2127 #ifdef CONFIG_PPP_FILTER
2128 /* check if the packet passes the pass and active filters */
2129 /* the filter instructions are constructed assuming
2130 a four-byte PPP header on each packet */
2131 if (ppp->pass_filter || ppp->active_filter) {
2132 if (skb_unclone(skb, GFP_ATOMIC))
2135 *skb_push(skb, 2) = 0;
2136 if (ppp->pass_filter &&
2137 BPF_PROG_RUN(ppp->pass_filter, skb) == 0) {
2139 netdev_printk(KERN_DEBUG, ppp->dev,
2140 "PPP: inbound frame "
2145 if (!(ppp->active_filter &&
2146 BPF_PROG_RUN(ppp->active_filter, skb) == 0))
2147 ppp->last_recv = jiffies;
2150 #endif /* CONFIG_PPP_FILTER */
2151 ppp->last_recv = jiffies;
2153 if ((ppp->dev->flags & IFF_UP) == 0 ||
2154 ppp->npmode[npi] != NPMODE_PASS) {
2157 /* chop off protocol */
2158 skb_pull_rcsum(skb, 2);
2159 skb->dev = ppp->dev;
2160 skb->protocol = htons(npindex_to_ethertype[npi]);
2161 skb_reset_mac_header(skb);
2162 skb_scrub_packet(skb, !net_eq(ppp->ppp_net,
2163 dev_net(ppp->dev)));
2171 ppp_receive_error(ppp);
2174 static struct sk_buff *
2175 ppp_decompress_frame(struct ppp *ppp, struct sk_buff *skb)
2177 int proto = PPP_PROTO(skb);
2181 /* Until we fix all the decompressor's need to make sure
2182 * data portion is linear.
2184 if (!pskb_may_pull(skb, skb->len))
2187 if (proto == PPP_COMP) {
2190 switch(ppp->rcomp->compress_proto) {
2192 obuff_size = ppp->mru + PPP_HDRLEN + 1;
2195 obuff_size = ppp->mru + PPP_HDRLEN;
2199 ns = dev_alloc_skb(obuff_size);
2201 netdev_err(ppp->dev, "ppp_decompress_frame: "
2205 /* the decompressor still expects the A/C bytes in the hdr */
2206 len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2,
2207 skb->len + 2, ns->data, obuff_size);
2209 /* Pass the compressed frame to pppd as an
2210 error indication. */
2211 if (len == DECOMP_FATALERROR)
2212 ppp->rstate |= SC_DC_FERROR;
2220 skb_pull(skb, 2); /* pull off the A/C bytes */
2223 /* Uncompressed frame - pass to decompressor so it
2224 can update its dictionary if necessary. */
2225 if (ppp->rcomp->incomp)
2226 ppp->rcomp->incomp(ppp->rc_state, skb->data - 2,
2233 ppp->rstate |= SC_DC_ERROR;
2234 ppp_receive_error(ppp);
2238 #ifdef CONFIG_PPP_MULTILINK
2240 * Receive a multilink frame.
2241 * We put it on the reconstruction queue and then pull off
2242 * as many completed frames as we can.
2245 ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
2249 int mphdrlen = (ppp->flags & SC_MP_SHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
2251 if (!pskb_may_pull(skb, mphdrlen + 1) || ppp->mrru == 0)
2252 goto err; /* no good, throw it away */
2254 /* Decode sequence number and begin/end bits */
2255 if (ppp->flags & SC_MP_SHORTSEQ) {
2256 seq = ((skb->data[2] & 0x0f) << 8) | skb->data[3];
2259 seq = (skb->data[3] << 16) | (skb->data[4] << 8)| skb->data[5];
2262 PPP_MP_CB(skb)->BEbits = skb->data[2];
2263 skb_pull(skb, mphdrlen); /* pull off PPP and MP headers */
2266 * Do protocol ID decompression on the first fragment of each packet.
2268 if ((PPP_MP_CB(skb)->BEbits & B) && (skb->data[0] & 1))
2269 *skb_push(skb, 1) = 0;
2272 * Expand sequence number to 32 bits, making it as close
2273 * as possible to ppp->minseq.
2275 seq |= ppp->minseq & ~mask;
2276 if ((int)(ppp->minseq - seq) > (int)(mask >> 1))
2278 else if ((int)(seq - ppp->minseq) > (int)(mask >> 1))
2279 seq -= mask + 1; /* should never happen */
2280 PPP_MP_CB(skb)->sequence = seq;
2284 * If this packet comes before the next one we were expecting,
2287 if (seq_before(seq, ppp->nextseq)) {
2289 ++ppp->dev->stats.rx_dropped;
2290 ppp_receive_error(ppp);
2295 * Reevaluate minseq, the minimum over all channels of the
2296 * last sequence number received on each channel. Because of
2297 * the increasing sequence number rule, we know that any fragment
2298 * before `minseq' which hasn't arrived is never going to arrive.
2299 * The list of channels can't change because we have the receive
2300 * side of the ppp unit locked.
2302 list_for_each_entry(ch, &ppp->channels, clist) {
2303 if (seq_before(ch->lastseq, seq))
2306 if (seq_before(ppp->minseq, seq))
2309 /* Put the fragment on the reconstruction queue */
2310 ppp_mp_insert(ppp, skb);
2312 /* If the queue is getting long, don't wait any longer for packets
2313 before the start of the queue. */
2314 if (skb_queue_len(&ppp->mrq) >= PPP_MP_MAX_QLEN) {
2315 struct sk_buff *mskb = skb_peek(&ppp->mrq);
2316 if (seq_before(ppp->minseq, PPP_MP_CB(mskb)->sequence))
2317 ppp->minseq = PPP_MP_CB(mskb)->sequence;
2320 /* Pull completed packets off the queue and receive them. */
2321 while ((skb = ppp_mp_reconstruct(ppp))) {
2322 if (pskb_may_pull(skb, 2))
2323 ppp_receive_nonmp_frame(ppp, skb);
2325 ++ppp->dev->stats.rx_length_errors;
2327 ppp_receive_error(ppp);
2335 ppp_receive_error(ppp);
2339 * Insert a fragment on the MP reconstruction queue.
2340 * The queue is ordered by increasing sequence number.
2343 ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb)
2346 struct sk_buff_head *list = &ppp->mrq;
2347 u32 seq = PPP_MP_CB(skb)->sequence;
2349 /* N.B. we don't need to lock the list lock because we have the
2350 ppp unit receive-side lock. */
2351 skb_queue_walk(list, p) {
2352 if (seq_before(seq, PPP_MP_CB(p)->sequence))
2355 __skb_queue_before(list, p, skb);
2359 * Reconstruct a packet from the MP fragment queue.
2360 * We go through increasing sequence numbers until we find a
2361 * complete packet, or we get to the sequence number for a fragment
2362 * which hasn't arrived but might still do so.
2364 static struct sk_buff *
2365 ppp_mp_reconstruct(struct ppp *ppp)
2367 u32 seq = ppp->nextseq;
2368 u32 minseq = ppp->minseq;
2369 struct sk_buff_head *list = &ppp->mrq;
2370 struct sk_buff *p, *tmp;
2371 struct sk_buff *head, *tail;
2372 struct sk_buff *skb = NULL;
2373 int lost = 0, len = 0;
2375 if (ppp->mrru == 0) /* do nothing until mrru is set */
2379 skb_queue_walk_safe(list, p, tmp) {
2381 if (seq_before(PPP_MP_CB(p)->sequence, seq)) {
2382 /* this can't happen, anyway ignore the skb */
2383 netdev_err(ppp->dev, "ppp_mp_reconstruct bad "
2385 PPP_MP_CB(p)->sequence, seq);
2386 __skb_unlink(p, list);
2390 if (PPP_MP_CB(p)->sequence != seq) {
2392 /* Fragment `seq' is missing. If it is after
2393 minseq, it might arrive later, so stop here. */
2394 if (seq_after(seq, minseq))
2396 /* Fragment `seq' is lost, keep going. */
2399 seq = seq_before(minseq, PPP_MP_CB(p)->sequence)?
2400 minseq + 1: PPP_MP_CB(p)->sequence;
2403 netdev_printk(KERN_DEBUG, ppp->dev,
2404 "lost frag %u..%u\n",
2411 * At this point we know that all the fragments from
2412 * ppp->nextseq to seq are either present or lost.
2413 * Also, there are no complete packets in the queue
2414 * that have no missing fragments and end before this
2418 /* B bit set indicates this fragment starts a packet */
2419 if (PPP_MP_CB(p)->BEbits & B) {
2427 /* Got a complete packet yet? */
2428 if (lost == 0 && (PPP_MP_CB(p)->BEbits & E) &&
2429 (PPP_MP_CB(head)->BEbits & B)) {
2430 if (len > ppp->mrru + 2) {
2431 ++ppp->dev->stats.rx_length_errors;
2432 netdev_printk(KERN_DEBUG, ppp->dev,
2433 "PPP: reconstructed packet"
2434 " is too long (%d)\n", len);
2439 ppp->nextseq = seq + 1;
2443 * If this is the ending fragment of a packet,
2444 * and we haven't found a complete valid packet yet,
2445 * we can discard up to and including this fragment.
2447 if (PPP_MP_CB(p)->BEbits & E) {
2448 struct sk_buff *tmp2;
2450 skb_queue_reverse_walk_from_safe(list, p, tmp2) {
2452 netdev_printk(KERN_DEBUG, ppp->dev,
2453 "discarding frag %u\n",
2454 PPP_MP_CB(p)->sequence);
2455 __skb_unlink(p, list);
2458 head = skb_peek(list);
2465 /* If we have a complete packet, copy it all into one skb. */
2467 /* If we have discarded any fragments,
2468 signal a receive error. */
2469 if (PPP_MP_CB(head)->sequence != ppp->nextseq) {
2470 skb_queue_walk_safe(list, p, tmp) {
2474 netdev_printk(KERN_DEBUG, ppp->dev,
2475 "discarding frag %u\n",
2476 PPP_MP_CB(p)->sequence);
2477 __skb_unlink(p, list);
2482 netdev_printk(KERN_DEBUG, ppp->dev,
2483 " missed pkts %u..%u\n",
2485 PPP_MP_CB(head)->sequence-1);
2486 ++ppp->dev->stats.rx_dropped;
2487 ppp_receive_error(ppp);
2492 struct sk_buff **fragpp = &skb_shinfo(skb)->frag_list;
2493 p = skb_queue_next(list, head);
2494 __skb_unlink(skb, list);
2495 skb_queue_walk_from_safe(list, p, tmp) {
2496 __skb_unlink(p, list);
2502 skb->data_len += p->len;
2503 skb->truesize += p->truesize;
2509 __skb_unlink(skb, list);
2512 ppp->nextseq = PPP_MP_CB(tail)->sequence + 1;
2517 #endif /* CONFIG_PPP_MULTILINK */
2520 * Channel interface.
2523 /* Create a new, unattached ppp channel. */
2524 int ppp_register_channel(struct ppp_channel *chan)
2526 return ppp_register_net_channel(current->nsproxy->net_ns, chan);
2529 /* Create a new, unattached ppp channel for specified net. */
2530 int ppp_register_net_channel(struct net *net, struct ppp_channel *chan)
2532 struct channel *pch;
2535 pch = kzalloc(sizeof(struct channel), GFP_KERNEL);
2539 pn = ppp_pernet(net);
2543 pch->chan_net = get_net(net);
2545 init_ppp_file(&pch->file, CHANNEL);
2546 pch->file.hdrlen = chan->hdrlen;
2547 #ifdef CONFIG_PPP_MULTILINK
2549 #endif /* CONFIG_PPP_MULTILINK */
2550 init_rwsem(&pch->chan_sem);
2551 spin_lock_init(&pch->downl);
2552 rwlock_init(&pch->upl);
2554 spin_lock_bh(&pn->all_channels_lock);
2555 pch->file.index = ++pn->last_channel_index;
2556 list_add(&pch->list, &pn->new_channels);
2557 atomic_inc(&channel_count);
2558 spin_unlock_bh(&pn->all_channels_lock);
2564 * Return the index of a channel.
2566 int ppp_channel_index(struct ppp_channel *chan)
2568 struct channel *pch = chan->ppp;
2571 return pch->file.index;
2576 * Return the PPP unit number to which a channel is connected.
2578 int ppp_unit_number(struct ppp_channel *chan)
2580 struct channel *pch = chan->ppp;
2584 read_lock_bh(&pch->upl);
2586 unit = pch->ppp->file.index;
2587 read_unlock_bh(&pch->upl);
2593 * Return the PPP device interface name of a channel.
2595 char *ppp_dev_name(struct ppp_channel *chan)
2597 struct channel *pch = chan->ppp;
2601 read_lock_bh(&pch->upl);
2602 if (pch->ppp && pch->ppp->dev)
2603 name = pch->ppp->dev->name;
2604 read_unlock_bh(&pch->upl);
2611 * Disconnect a channel from the generic layer.
2612 * This must be called in process context.
2615 ppp_unregister_channel(struct ppp_channel *chan)
2617 struct channel *pch = chan->ppp;
2621 return; /* should never happen */
2626 * This ensures that we have returned from any calls into the
2627 * the channel's start_xmit or ioctl routine before we proceed.
2629 down_write(&pch->chan_sem);
2630 spin_lock_bh(&pch->downl);
2632 spin_unlock_bh(&pch->downl);
2633 up_write(&pch->chan_sem);
2634 ppp_disconnect_channel(pch);
2636 pn = ppp_pernet(pch->chan_net);
2637 spin_lock_bh(&pn->all_channels_lock);
2638 list_del(&pch->list);
2639 spin_unlock_bh(&pn->all_channels_lock);
2642 wake_up_interruptible(&pch->file.rwait);
2643 if (atomic_dec_and_test(&pch->file.refcnt))
2644 ppp_destroy_channel(pch);
2648 * Callback from a channel when it can accept more to transmit.
2649 * This should be called at BH/softirq level, not interrupt level.
2652 ppp_output_wakeup(struct ppp_channel *chan)
2654 struct channel *pch = chan->ppp;
2658 ppp_channel_push(pch);
2662 * Compression control.
2665 /* Process the PPPIOCSCOMPRESS ioctl. */
2667 ppp_set_compress(struct ppp *ppp, unsigned long arg)
2670 struct compressor *cp, *ocomp;
2671 struct ppp_option_data data;
2672 void *state, *ostate;
2673 unsigned char ccp_option[CCP_MAX_OPTION_LENGTH];
2676 if (copy_from_user(&data, (void __user *) arg, sizeof(data)))
2678 if (data.length > CCP_MAX_OPTION_LENGTH)
2680 if (copy_from_user(ccp_option, (void __user *) data.ptr, data.length))
2684 if (data.length < 2 || ccp_option[1] < 2 || ccp_option[1] > data.length)
2687 cp = try_then_request_module(
2688 find_compressor(ccp_option[0]),
2689 "ppp-compress-%d", ccp_option[0]);
2694 if (data.transmit) {
2695 state = cp->comp_alloc(ccp_option, data.length);
2698 ppp->xstate &= ~SC_COMP_RUN;
2700 ostate = ppp->xc_state;
2702 ppp->xc_state = state;
2703 ppp_xmit_unlock(ppp);
2705 ocomp->comp_free(ostate);
2706 module_put(ocomp->owner);
2710 module_put(cp->owner);
2713 state = cp->decomp_alloc(ccp_option, data.length);
2716 ppp->rstate &= ~SC_DECOMP_RUN;
2718 ostate = ppp->rc_state;
2720 ppp->rc_state = state;
2721 ppp_recv_unlock(ppp);
2723 ocomp->decomp_free(ostate);
2724 module_put(ocomp->owner);
2728 module_put(cp->owner);
2736 * Look at a CCP packet and update our state accordingly.
2737 * We assume the caller has the xmit or recv path locked.
2740 ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound)
2745 if (!pskb_may_pull(skb, CCP_HDRLEN + 2))
2746 return; /* no header */
2749 switch (CCP_CODE(dp)) {
2752 /* A ConfReq starts negotiation of compression
2753 * in one direction of transmission,
2754 * and hence brings it down...but which way?
2757 * A ConfReq indicates what the sender would like to receive
2760 /* He is proposing what I should send */
2761 ppp->xstate &= ~SC_COMP_RUN;
2763 /* I am proposing to what he should send */
2764 ppp->rstate &= ~SC_DECOMP_RUN;
2771 * CCP is going down, both directions of transmission
2773 ppp->rstate &= ~SC_DECOMP_RUN;
2774 ppp->xstate &= ~SC_COMP_RUN;
2778 if ((ppp->flags & (SC_CCP_OPEN | SC_CCP_UP)) != SC_CCP_OPEN)
2780 len = CCP_LENGTH(dp);
2781 if (!pskb_may_pull(skb, len + 2))
2782 return; /* too short */
2785 if (len < CCP_OPT_MINLEN || len < CCP_OPT_LENGTH(dp))
2788 /* we will start receiving compressed packets */
2791 if (ppp->rcomp->decomp_init(ppp->rc_state, dp, len,
2792 ppp->file.index, 0, ppp->mru, ppp->debug)) {
2793 ppp->rstate |= SC_DECOMP_RUN;
2794 ppp->rstate &= ~(SC_DC_ERROR | SC_DC_FERROR);
2797 /* we will soon start sending compressed packets */
2800 if (ppp->xcomp->comp_init(ppp->xc_state, dp, len,
2801 ppp->file.index, 0, ppp->debug))
2802 ppp->xstate |= SC_COMP_RUN;
2807 /* reset the [de]compressor */
2808 if ((ppp->flags & SC_CCP_UP) == 0)
2811 if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN)) {
2812 ppp->rcomp->decomp_reset(ppp->rc_state);
2813 ppp->rstate &= ~SC_DC_ERROR;
2816 if (ppp->xc_state && (ppp->xstate & SC_COMP_RUN))
2817 ppp->xcomp->comp_reset(ppp->xc_state);
2823 /* Free up compression resources. */
2825 ppp_ccp_closed(struct ppp *ppp)
2827 void *xstate, *rstate;
2828 struct compressor *xcomp, *rcomp;
2831 ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP);
2834 xstate = ppp->xc_state;
2835 ppp->xc_state = NULL;
2838 rstate = ppp->rc_state;
2839 ppp->rc_state = NULL;
2843 xcomp->comp_free(xstate);
2844 module_put(xcomp->owner);
2847 rcomp->decomp_free(rstate);
2848 module_put(rcomp->owner);
2852 /* List of compressors. */
2853 static LIST_HEAD(compressor_list);
2854 static DEFINE_SPINLOCK(compressor_list_lock);
2856 struct compressor_entry {
2857 struct list_head list;
2858 struct compressor *comp;
2861 static struct compressor_entry *
2862 find_comp_entry(int proto)
2864 struct compressor_entry *ce;
2866 list_for_each_entry(ce, &compressor_list, list) {
2867 if (ce->comp->compress_proto == proto)
2873 /* Register a compressor */
2875 ppp_register_compressor(struct compressor *cp)
2877 struct compressor_entry *ce;
2879 spin_lock(&compressor_list_lock);
2881 if (find_comp_entry(cp->compress_proto))
2884 ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC);
2889 list_add(&ce->list, &compressor_list);
2891 spin_unlock(&compressor_list_lock);
2895 /* Unregister a compressor */
2897 ppp_unregister_compressor(struct compressor *cp)
2899 struct compressor_entry *ce;
2901 spin_lock(&compressor_list_lock);
2902 ce = find_comp_entry(cp->compress_proto);
2903 if (ce && ce->comp == cp) {
2904 list_del(&ce->list);
2907 spin_unlock(&compressor_list_lock);
2910 /* Find a compressor. */
2911 static struct compressor *
2912 find_compressor(int type)
2914 struct compressor_entry *ce;
2915 struct compressor *cp = NULL;
2917 spin_lock(&compressor_list_lock);
2918 ce = find_comp_entry(type);
2921 if (!try_module_get(cp->owner))
2924 spin_unlock(&compressor_list_lock);
2929 * Miscelleneous stuff.
2933 ppp_get_stats(struct ppp *ppp, struct ppp_stats *st)
2935 struct slcompress *vj = ppp->vj;
2937 memset(st, 0, sizeof(*st));
2938 st->p.ppp_ipackets = ppp->stats64.rx_packets;
2939 st->p.ppp_ierrors = ppp->dev->stats.rx_errors;
2940 st->p.ppp_ibytes = ppp->stats64.rx_bytes;
2941 st->p.ppp_opackets = ppp->stats64.tx_packets;
2942 st->p.ppp_oerrors = ppp->dev->stats.tx_errors;
2943 st->p.ppp_obytes = ppp->stats64.tx_bytes;
2946 st->vj.vjs_packets = vj->sls_o_compressed + vj->sls_o_uncompressed;
2947 st->vj.vjs_compressed = vj->sls_o_compressed;
2948 st->vj.vjs_searches = vj->sls_o_searches;
2949 st->vj.vjs_misses = vj->sls_o_misses;
2950 st->vj.vjs_errorin = vj->sls_i_error;
2951 st->vj.vjs_tossed = vj->sls_i_tossed;
2952 st->vj.vjs_uncompressedin = vj->sls_i_uncompressed;
2953 st->vj.vjs_compressedin = vj->sls_i_compressed;
2957 * Stuff for handling the lists of ppp units and channels
2958 * and for initialization.
2962 * Create a new ppp interface unit. Fails if it can't allocate memory
2963 * or if there is already a unit with the requested number.
2964 * unit == -1 means allocate a new number.
2966 static int ppp_create_interface(struct net *net, struct file *file, int *unit)
2968 struct ppp_config conf = {
2971 .ifname_is_set = false,
2973 struct net_device *dev;
2977 dev = alloc_netdev(sizeof(struct ppp), "", NET_NAME_ENUM, ppp_setup);
2982 dev_net_set(dev, net);
2983 dev->rtnl_link_ops = &ppp_link_ops;
2987 err = ppp_dev_configure(net, dev, &conf);
2990 ppp = netdev_priv(dev);
2991 *unit = ppp->file.index;
3005 * Initialize a ppp_file structure.
3008 init_ppp_file(struct ppp_file *pf, int kind)
3011 skb_queue_head_init(&pf->xq);
3012 skb_queue_head_init(&pf->rq);
3013 atomic_set(&pf->refcnt, 1);
3014 init_waitqueue_head(&pf->rwait);
3018 * Free the memory used by a ppp unit. This is only called once
3019 * there are no channels connected to the unit and no file structs
3020 * that reference the unit.
3022 static void ppp_destroy_interface(struct ppp *ppp)
3024 atomic_dec(&ppp_unit_count);
3026 if (!ppp->file.dead || ppp->n_channels) {
3027 /* "can't happen" */
3028 netdev_err(ppp->dev, "ppp: destroying ppp struct %p "
3029 "but dead=%d n_channels=%d !\n",
3030 ppp, ppp->file.dead, ppp->n_channels);
3034 ppp_ccp_closed(ppp);
3039 skb_queue_purge(&ppp->file.xq);
3040 skb_queue_purge(&ppp->file.rq);
3041 #ifdef CONFIG_PPP_MULTILINK
3042 skb_queue_purge(&ppp->mrq);
3043 #endif /* CONFIG_PPP_MULTILINK */
3044 #ifdef CONFIG_PPP_FILTER
3045 if (ppp->pass_filter) {
3046 bpf_prog_destroy(ppp->pass_filter);
3047 ppp->pass_filter = NULL;
3050 if (ppp->active_filter) {
3051 bpf_prog_destroy(ppp->active_filter);
3052 ppp->active_filter = NULL;
3054 #endif /* CONFIG_PPP_FILTER */
3056 kfree_skb(ppp->xmit_pending);
3058 free_netdev(ppp->dev);
3062 * Locate an existing ppp unit.
3063 * The caller should have locked the all_ppp_mutex.
3066 ppp_find_unit(struct ppp_net *pn, int unit)
3068 return unit_find(&pn->units_idr, unit);
3072 * Locate an existing ppp channel.
3073 * The caller should have locked the all_channels_lock.
3074 * First we look in the new_channels list, then in the
3075 * all_channels list. If found in the new_channels list,
3076 * we move it to the all_channels list. This is for speed
3077 * when we have a lot of channels in use.
3079 static struct channel *
3080 ppp_find_channel(struct ppp_net *pn, int unit)
3082 struct channel *pch;
3084 list_for_each_entry(pch, &pn->new_channels, list) {
3085 if (pch->file.index == unit) {
3086 list_move(&pch->list, &pn->all_channels);
3091 list_for_each_entry(pch, &pn->all_channels, list) {
3092 if (pch->file.index == unit)
3100 * Connect a PPP channel to a PPP interface unit.
3103 ppp_connect_channel(struct channel *pch, int unit)
3110 pn = ppp_pernet(pch->chan_net);
3112 mutex_lock(&pn->all_ppp_mutex);
3113 ppp = ppp_find_unit(pn, unit);
3116 write_lock_bh(&pch->upl);
3122 if (pch->file.hdrlen > ppp->file.hdrlen)
3123 ppp->file.hdrlen = pch->file.hdrlen;
3124 hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */
3125 if (hdrlen > ppp->dev->hard_header_len)
3126 ppp->dev->hard_header_len = hdrlen;
3127 list_add_tail(&pch->clist, &ppp->channels);
3130 atomic_inc(&ppp->file.refcnt);
3135 write_unlock_bh(&pch->upl);
3137 mutex_unlock(&pn->all_ppp_mutex);
3142 * Disconnect a channel from its ppp unit.
3145 ppp_disconnect_channel(struct channel *pch)
3150 write_lock_bh(&pch->upl);
3153 write_unlock_bh(&pch->upl);
3155 /* remove it from the ppp unit's list */
3157 list_del(&pch->clist);
3158 if (--ppp->n_channels == 0)
3159 wake_up_interruptible(&ppp->file.rwait);
3161 if (atomic_dec_and_test(&ppp->file.refcnt))
3162 ppp_destroy_interface(ppp);
3169 * Free up the resources used by a ppp channel.
3171 static void ppp_destroy_channel(struct channel *pch)
3173 put_net(pch->chan_net);
3174 pch->chan_net = NULL;
3176 atomic_dec(&channel_count);
3178 if (!pch->file.dead) {
3179 /* "can't happen" */
3180 pr_err("ppp: destroying undead channel %p !\n", pch);
3183 skb_queue_purge(&pch->file.xq);
3184 skb_queue_purge(&pch->file.rq);
3188 static void __exit ppp_cleanup(void)
3190 /* should never happen */
3191 if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count))
3192 pr_err("PPP: removing module but units remain!\n");
3193 rtnl_link_unregister(&ppp_link_ops);
3194 unregister_chrdev(PPP_MAJOR, "ppp");
3195 device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0));
3196 class_destroy(ppp_class);
3197 unregister_pernet_device(&ppp_net_ops);
3201 * Units handling. Caller must protect concurrent access
3202 * by holding all_ppp_mutex
3205 /* associate pointer with specified number */
3206 static int unit_set(struct idr *p, void *ptr, int n)
3210 unit = idr_alloc(p, ptr, n, n + 1, GFP_KERNEL);
3211 if (unit == -ENOSPC)
3216 /* get new free unit number and associate pointer with it */
3217 static int unit_get(struct idr *p, void *ptr)
3219 return idr_alloc(p, ptr, 0, 0, GFP_KERNEL);
3222 /* put unit number back to a pool */
3223 static void unit_put(struct idr *p, int n)
3228 /* get pointer associated with the number */
3229 static void *unit_find(struct idr *p, int n)
3231 return idr_find(p, n);
3234 /* Module/initialization stuff */
3236 module_init(ppp_init);
3237 module_exit(ppp_cleanup);
3239 EXPORT_SYMBOL(ppp_register_net_channel);
3240 EXPORT_SYMBOL(ppp_register_channel);
3241 EXPORT_SYMBOL(ppp_unregister_channel);
3242 EXPORT_SYMBOL(ppp_channel_index);
3243 EXPORT_SYMBOL(ppp_unit_number);
3244 EXPORT_SYMBOL(ppp_dev_name);
3245 EXPORT_SYMBOL(ppp_input);
3246 EXPORT_SYMBOL(ppp_input_error);
3247 EXPORT_SYMBOL(ppp_output_wakeup);
3248 EXPORT_SYMBOL(ppp_register_compressor);
3249 EXPORT_SYMBOL(ppp_unregister_compressor);
3250 MODULE_LICENSE("GPL");
3251 MODULE_ALIAS_CHARDEV(PPP_MAJOR, 0);
3252 MODULE_ALIAS_RTNL_LINK("ppp");
3253 MODULE_ALIAS("devname:ppp");