2 * Generic PPP layer for Linux.
4 * Copyright 1999-2002 Paul Mackerras.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
11 * The generic PPP layer handles the PPP network interfaces, the
12 * /dev/ppp device, packet and VJ compression, and multilink.
13 * It talks to PPP `channels' via the interface defined in
14 * include/linux/ppp_channel.h. Channels provide the basic means for
15 * sending and receiving PPP frames on some kind of communications
18 * Part of the code in this driver was inspired by the old async-only
19 * PPP driver, written by Michael Callahan and Al Longyear, and
20 * subsequently hacked by Paul Mackerras.
22 * ==FILEVERSION 20041108==
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/kmod.h>
28 #include <linux/init.h>
29 #include <linux/list.h>
30 #include <linux/idr.h>
31 #include <linux/netdevice.h>
32 #include <linux/poll.h>
33 #include <linux/ppp_defs.h>
34 #include <linux/filter.h>
35 #include <linux/if_ppp.h>
36 #include <linux/ppp_channel.h>
37 #include <linux/ppp-comp.h>
38 #include <linux/skbuff.h>
39 #include <linux/rtnetlink.h>
40 #include <linux/if_arp.h>
42 #include <linux/tcp.h>
43 #include <linux/spinlock.h>
44 #include <linux/rwsem.h>
45 #include <linux/stddef.h>
46 #include <linux/device.h>
47 #include <linux/mutex.h>
48 #include <linux/slab.h>
49 #include <asm/unaligned.h>
50 #include <net/slhc_vj.h>
51 #include <linux/atomic.h>
53 #include <linux/nsproxy.h>
54 #include <net/net_namespace.h>
55 #include <net/netns/generic.h>
57 #define PPP_VERSION "2.4.2"
60 * Network protocols we support.
62 #define NP_IP 0 /* Internet Protocol V4 */
63 #define NP_IPV6 1 /* Internet Protocol V6 */
64 #define NP_IPX 2 /* IPX protocol */
65 #define NP_AT 3 /* Appletalk protocol */
66 #define NP_MPLS_UC 4 /* MPLS unicast */
67 #define NP_MPLS_MC 5 /* MPLS multicast */
68 #define NUM_NP 6 /* Number of NPs. */
70 #define MPHDRLEN 6 /* multilink protocol header length */
71 #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */
74 * An instance of /dev/ppp can be associated with either a ppp
75 * interface unit or a ppp channel. In both cases, file->private_data
76 * points to one of these.
82 struct sk_buff_head xq; /* pppd transmit queue */
83 struct sk_buff_head rq; /* receive queue for pppd */
84 wait_queue_head_t rwait; /* for poll on reading /dev/ppp */
85 atomic_t refcnt; /* # refs (incl /dev/ppp attached) */
86 int hdrlen; /* space to leave for headers */
87 int index; /* interface unit / channel number */
88 int dead; /* unit/channel has been shut down */
91 #define PF_TO_X(pf, X) container_of(pf, X, file)
93 #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp)
94 #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel)
97 * Data structure describing one ppp unit.
98 * A ppp unit corresponds to a ppp network interface device
99 * and represents a multilink bundle.
100 * It can have 0 or more ppp channels connected to it.
103 struct ppp_file file; /* stuff for read/write/poll 0 */
104 struct file *owner; /* file that owns this unit 48 */
105 struct list_head channels; /* list of attached channels 4c */
106 int n_channels; /* how many channels are attached 54 */
107 spinlock_t rlock; /* lock for receive side 58 */
108 spinlock_t wlock; /* lock for transmit side 5c */
109 int mru; /* max receive unit 60 */
110 unsigned int flags; /* control bits 64 */
111 unsigned int xstate; /* transmit state bits 68 */
112 unsigned int rstate; /* receive state bits 6c */
113 int debug; /* debug flags 70 */
114 struct slcompress *vj; /* state for VJ header compression */
115 enum NPmode npmode[NUM_NP]; /* what to do with each net proto 78 */
116 struct sk_buff *xmit_pending; /* a packet ready to go out 88 */
117 struct compressor *xcomp; /* transmit packet compressor 8c */
118 void *xc_state; /* its internal state 90 */
119 struct compressor *rcomp; /* receive decompressor 94 */
120 void *rc_state; /* its internal state 98 */
121 unsigned long last_xmit; /* jiffies when last pkt sent 9c */
122 unsigned long last_recv; /* jiffies when last pkt rcvd a0 */
123 struct net_device *dev; /* network interface device a4 */
124 int closing; /* is device closing down? a8 */
125 #ifdef CONFIG_PPP_MULTILINK
126 int nxchan; /* next channel to send something on */
127 u32 nxseq; /* next sequence number to send */
128 int mrru; /* MP: max reconst. receive unit */
129 u32 nextseq; /* MP: seq no of next packet */
130 u32 minseq; /* MP: min of most recent seqnos */
131 struct sk_buff_head mrq; /* MP: receive reconstruction queue */
132 #endif /* CONFIG_PPP_MULTILINK */
133 #ifdef CONFIG_PPP_FILTER
134 struct sock_filter *pass_filter; /* filter for packets to pass */
135 struct sock_filter *active_filter;/* filter for pkts to reset idle */
136 unsigned pass_len, active_len;
137 #endif /* CONFIG_PPP_FILTER */
138 struct net *ppp_net; /* the net we belong to */
142 * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
143 * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP,
145 * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR.
146 * Bits in xstate: SC_COMP_RUN
148 #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \
149 |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \
150 |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP)
153 * Private data structure for each channel.
154 * This includes the data structure used for multilink.
157 struct ppp_file file; /* stuff for read/write/poll */
158 struct list_head list; /* link in all/new_channels list */
159 struct ppp_channel *chan; /* public channel data structure */
160 struct rw_semaphore chan_sem; /* protects `chan' during chan ioctl */
161 spinlock_t downl; /* protects `chan', file.xq dequeue */
162 struct ppp *ppp; /* ppp unit we're connected to */
163 struct net *chan_net; /* the net channel belongs to */
164 struct list_head clist; /* link in list of channels per unit */
165 rwlock_t upl; /* protects `ppp' */
166 #ifdef CONFIG_PPP_MULTILINK
167 u8 avail; /* flag used in multilink stuff */
168 u8 had_frag; /* >= 1 fragments have been sent */
169 u32 lastseq; /* MP: last sequence # received */
170 int speed; /* speed of the corresponding ppp channel*/
171 #endif /* CONFIG_PPP_MULTILINK */
175 * SMP locking issues:
176 * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels
177 * list and the ppp.n_channels field, you need to take both locks
178 * before you modify them.
179 * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
183 static DEFINE_MUTEX(ppp_mutex);
184 static atomic_t ppp_unit_count = ATOMIC_INIT(0);
185 static atomic_t channel_count = ATOMIC_INIT(0);
187 /* per-net private data for this module */
188 static int ppp_net_id __read_mostly;
190 /* units to ppp mapping */
191 struct idr units_idr;
194 * all_ppp_mutex protects the units_idr mapping.
195 * It also ensures that finding a ppp unit in the units_idr
196 * map and updating its file.refcnt field is atomic.
198 struct mutex all_ppp_mutex;
201 struct list_head all_channels;
202 struct list_head new_channels;
203 int last_channel_index;
206 * all_channels_lock protects all_channels and
207 * last_channel_index, and the atomicity of find
208 * a channel and updating its file.refcnt field.
210 spinlock_t all_channels_lock;
213 /* Get the PPP protocol number from a skb */
214 #define PPP_PROTO(skb) get_unaligned_be16((skb)->data)
216 /* We limit the length of ppp->file.rq to this (arbitrary) value */
217 #define PPP_MAX_RQLEN 32
220 * Maximum number of multilink fragments queued up.
221 * This has to be large enough to cope with the maximum latency of
222 * the slowest channel relative to the others. Strictly it should
223 * depend on the number of channels and their characteristics.
225 #define PPP_MP_MAX_QLEN 128
227 /* Multilink header bits. */
228 #define B 0x80 /* this fragment begins a packet */
229 #define E 0x40 /* this fragment ends a packet */
231 /* Compare multilink sequence numbers (assumed to be 32 bits wide) */
232 #define seq_before(a, b) ((s32)((a) - (b)) < 0)
233 #define seq_after(a, b) ((s32)((a) - (b)) > 0)
236 static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
237 struct file *file, unsigned int cmd, unsigned long arg);
238 static void ppp_xmit_process(struct ppp *ppp);
239 static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb);
240 static void ppp_push(struct ppp *ppp);
241 static void ppp_channel_push(struct channel *pch);
242 static void ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb,
243 struct channel *pch);
244 static void ppp_receive_error(struct ppp *ppp);
245 static void ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb);
246 static struct sk_buff *ppp_decompress_frame(struct ppp *ppp,
247 struct sk_buff *skb);
248 #ifdef CONFIG_PPP_MULTILINK
249 static void ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb,
250 struct channel *pch);
251 static void ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb);
252 static struct sk_buff *ppp_mp_reconstruct(struct ppp *ppp);
253 static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb);
254 #endif /* CONFIG_PPP_MULTILINK */
255 static int ppp_set_compress(struct ppp *ppp, unsigned long arg);
256 static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound);
257 static void ppp_ccp_closed(struct ppp *ppp);
258 static struct compressor *find_compressor(int type);
259 static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st);
260 static struct ppp *ppp_create_interface(struct net *net, int unit, int *retp);
261 static void init_ppp_file(struct ppp_file *pf, int kind);
262 static void ppp_shutdown_interface(struct ppp *ppp);
263 static void ppp_destroy_interface(struct ppp *ppp);
264 static struct ppp *ppp_find_unit(struct ppp_net *pn, int unit);
265 static struct channel *ppp_find_channel(struct ppp_net *pn, int unit);
266 static int ppp_connect_channel(struct channel *pch, int unit);
267 static int ppp_disconnect_channel(struct channel *pch);
268 static void ppp_destroy_channel(struct channel *pch);
269 static int unit_get(struct idr *p, void *ptr);
270 static int unit_set(struct idr *p, void *ptr, int n);
271 static void unit_put(struct idr *p, int n);
272 static void *unit_find(struct idr *p, int n);
274 static struct class *ppp_class;
276 /* per net-namespace data */
277 static inline struct ppp_net *ppp_pernet(struct net *net)
281 return net_generic(net, ppp_net_id);
284 /* Translates a PPP protocol number to a NP index (NP == network protocol) */
285 static inline int proto_to_npindex(int proto)
304 /* Translates an NP index into a PPP protocol number */
305 static const int npindex_to_proto[NUM_NP] = {
314 /* Translates an ethertype into an NP index */
315 static inline int ethertype_to_npindex(int ethertype)
335 /* Translates an NP index into an ethertype */
336 static const int npindex_to_ethertype[NUM_NP] = {
348 #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock)
349 #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock)
350 #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock)
351 #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock)
352 #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \
353 ppp_recv_lock(ppp); } while (0)
354 #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \
355 ppp_xmit_unlock(ppp); } while (0)
358 * /dev/ppp device routines.
359 * The /dev/ppp device is used by pppd to control the ppp unit.
360 * It supports the read, write, ioctl and poll functions.
361 * Open instances of /dev/ppp can be in one of three states:
362 * unattached, attached to a ppp unit, or attached to a ppp channel.
364 static int ppp_open(struct inode *inode, struct file *file)
367 * This could (should?) be enforced by the permissions on /dev/ppp.
369 if (!capable(CAP_NET_ADMIN))
374 static int ppp_release(struct inode *unused, struct file *file)
376 struct ppp_file *pf = file->private_data;
380 file->private_data = NULL;
381 if (pf->kind == INTERFACE) {
383 if (file == ppp->owner)
384 ppp_shutdown_interface(ppp);
386 if (atomic_dec_and_test(&pf->refcnt)) {
389 ppp_destroy_interface(PF_TO_PPP(pf));
392 ppp_destroy_channel(PF_TO_CHANNEL(pf));
400 static ssize_t ppp_read(struct file *file, char __user *buf,
401 size_t count, loff_t *ppos)
403 struct ppp_file *pf = file->private_data;
404 DECLARE_WAITQUEUE(wait, current);
406 struct sk_buff *skb = NULL;
413 add_wait_queue(&pf->rwait, &wait);
415 set_current_state(TASK_INTERRUPTIBLE);
416 skb = skb_dequeue(&pf->rq);
422 if (pf->kind == INTERFACE) {
424 * Return 0 (EOF) on an interface that has no
425 * channels connected, unless it is looping
426 * network traffic (demand mode).
428 struct ppp *ppp = PF_TO_PPP(pf);
429 if (ppp->n_channels == 0 &&
430 (ppp->flags & SC_LOOP_TRAFFIC) == 0)
434 if (file->f_flags & O_NONBLOCK)
437 if (signal_pending(current))
441 set_current_state(TASK_RUNNING);
442 remove_wait_queue(&pf->rwait, &wait);
448 if (skb->len > count)
453 if (skb_copy_datagram_iovec(skb, 0, &iov, skb->len))
463 static ssize_t ppp_write(struct file *file, const char __user *buf,
464 size_t count, loff_t *ppos)
466 struct ppp_file *pf = file->private_data;
473 skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL);
476 skb_reserve(skb, pf->hdrlen);
478 if (copy_from_user(skb_put(skb, count), buf, count)) {
483 skb_queue_tail(&pf->xq, skb);
487 ppp_xmit_process(PF_TO_PPP(pf));
490 ppp_channel_push(PF_TO_CHANNEL(pf));
500 /* No kernel lock - fine */
501 static unsigned int ppp_poll(struct file *file, poll_table *wait)
503 struct ppp_file *pf = file->private_data;
508 poll_wait(file, &pf->rwait, wait);
509 mask = POLLOUT | POLLWRNORM;
510 if (skb_peek(&pf->rq))
511 mask |= POLLIN | POLLRDNORM;
514 else if (pf->kind == INTERFACE) {
515 /* see comment in ppp_read */
516 struct ppp *ppp = PF_TO_PPP(pf);
517 if (ppp->n_channels == 0 &&
518 (ppp->flags & SC_LOOP_TRAFFIC) == 0)
519 mask |= POLLIN | POLLRDNORM;
525 #ifdef CONFIG_PPP_FILTER
526 static int get_filter(void __user *arg, struct sock_filter **p)
528 struct sock_fprog uprog;
529 struct sock_filter *code = NULL;
532 if (copy_from_user(&uprog, arg, sizeof(uprog)))
540 len = uprog.len * sizeof(struct sock_filter);
541 code = memdup_user(uprog.filter, len);
543 return PTR_ERR(code);
545 err = sk_chk_filter(code, uprog.len);
554 #endif /* CONFIG_PPP_FILTER */
556 static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
560 int err = -EFAULT, val, val2, i;
561 struct ppp_idle idle;
564 struct slcompress *vj;
565 void __user *argp = (void __user *)arg;
566 int __user *p = argp;
568 mutex_lock(&ppp_mutex);
570 pf = file->private_data;
572 err = ppp_unattached_ioctl(current->nsproxy->net_ns,
577 if (cmd == PPPIOCDETACH) {
579 * We have to be careful here... if the file descriptor
580 * has been dup'd, we could have another process in the
581 * middle of a poll using the same file *, so we had
582 * better not free the interface data structures -
583 * instead we fail the ioctl. Even in this case, we
584 * shut down the interface if we are the owner of it.
585 * Actually, we should get rid of PPPIOCDETACH, userland
586 * (i.e. pppd) could achieve the same effect by closing
587 * this fd and reopening /dev/ppp.
590 if (pf->kind == INTERFACE) {
592 if (file == ppp->owner)
593 ppp_shutdown_interface(ppp);
595 if (atomic_long_read(&file->f_count) < 2) {
596 ppp_release(NULL, file);
599 pr_warn("PPPIOCDETACH file->f_count=%ld\n",
600 atomic_long_read(&file->f_count));
604 if (pf->kind == CHANNEL) {
606 struct ppp_channel *chan;
608 pch = PF_TO_CHANNEL(pf);
612 if (get_user(unit, p))
614 err = ppp_connect_channel(pch, unit);
618 err = ppp_disconnect_channel(pch);
622 down_read(&pch->chan_sem);
625 if (chan && chan->ops->ioctl)
626 err = chan->ops->ioctl(chan, cmd, arg);
627 up_read(&pch->chan_sem);
632 if (pf->kind != INTERFACE) {
634 pr_err("PPP: not interface or channel??\n");
642 if (get_user(val, p))
649 if (get_user(val, p))
652 cflags = ppp->flags & ~val;
653 ppp->flags = val & SC_FLAG_BITS;
655 if (cflags & SC_CCP_OPEN)
661 val = ppp->flags | ppp->xstate | ppp->rstate;
662 if (put_user(val, p))
667 case PPPIOCSCOMPRESS:
668 err = ppp_set_compress(ppp, arg);
672 if (put_user(ppp->file.index, p))
678 if (get_user(val, p))
685 if (put_user(ppp->debug, p))
691 idle.xmit_idle = (jiffies - ppp->last_xmit) / HZ;
692 idle.recv_idle = (jiffies - ppp->last_recv) / HZ;
693 if (copy_to_user(argp, &idle, sizeof(idle)))
699 if (get_user(val, p))
702 if ((val >> 16) != 0) {
706 vj = slhc_init(val2+1, val+1);
721 if (copy_from_user(&npi, argp, sizeof(npi)))
723 err = proto_to_npindex(npi.protocol);
727 if (cmd == PPPIOCGNPMODE) {
729 npi.mode = ppp->npmode[i];
730 if (copy_to_user(argp, &npi, sizeof(npi)))
733 ppp->npmode[i] = npi.mode;
734 /* we may be able to transmit more packets now (??) */
735 netif_wake_queue(ppp->dev);
740 #ifdef CONFIG_PPP_FILTER
743 struct sock_filter *code;
744 err = get_filter(argp, &code);
747 kfree(ppp->pass_filter);
748 ppp->pass_filter = code;
757 struct sock_filter *code;
758 err = get_filter(argp, &code);
761 kfree(ppp->active_filter);
762 ppp->active_filter = code;
763 ppp->active_len = err;
769 #endif /* CONFIG_PPP_FILTER */
771 #ifdef CONFIG_PPP_MULTILINK
773 if (get_user(val, p))
777 ppp_recv_unlock(ppp);
780 #endif /* CONFIG_PPP_MULTILINK */
787 mutex_unlock(&ppp_mutex);
792 static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
793 struct file *file, unsigned int cmd, unsigned long arg)
795 int unit, err = -EFAULT;
797 struct channel *chan;
799 int __user *p = (int __user *)arg;
803 /* Create a new ppp unit */
804 if (get_user(unit, p))
806 ppp = ppp_create_interface(net, unit, &err);
809 file->private_data = &ppp->file;
812 if (put_user(ppp->file.index, p))
818 /* Attach to an existing ppp unit */
819 if (get_user(unit, p))
822 pn = ppp_pernet(net);
823 mutex_lock(&pn->all_ppp_mutex);
824 ppp = ppp_find_unit(pn, unit);
826 atomic_inc(&ppp->file.refcnt);
827 file->private_data = &ppp->file;
830 mutex_unlock(&pn->all_ppp_mutex);
834 if (get_user(unit, p))
837 pn = ppp_pernet(net);
838 spin_lock_bh(&pn->all_channels_lock);
839 chan = ppp_find_channel(pn, unit);
841 atomic_inc(&chan->file.refcnt);
842 file->private_data = &chan->file;
845 spin_unlock_bh(&pn->all_channels_lock);
855 static const struct file_operations ppp_device_fops = {
856 .owner = THIS_MODULE,
860 .unlocked_ioctl = ppp_ioctl,
862 .release = ppp_release,
863 .llseek = noop_llseek,
866 static __net_init int ppp_init_net(struct net *net)
868 struct ppp_net *pn = net_generic(net, ppp_net_id);
870 idr_init(&pn->units_idr);
871 mutex_init(&pn->all_ppp_mutex);
873 INIT_LIST_HEAD(&pn->all_channels);
874 INIT_LIST_HEAD(&pn->new_channels);
876 spin_lock_init(&pn->all_channels_lock);
881 static __net_exit void ppp_exit_net(struct net *net)
883 struct ppp_net *pn = net_generic(net, ppp_net_id);
885 idr_destroy(&pn->units_idr);
888 static struct pernet_operations ppp_net_ops = {
889 .init = ppp_init_net,
890 .exit = ppp_exit_net,
892 .size = sizeof(struct ppp_net),
895 #define PPP_MAJOR 108
897 /* Called at boot time if ppp is compiled into the kernel,
898 or at module load time (from init_module) if compiled as a module. */
899 static int __init ppp_init(void)
903 pr_info("PPP generic driver version " PPP_VERSION "\n");
905 err = register_pernet_device(&ppp_net_ops);
907 pr_err("failed to register PPP pernet device (%d)\n", err);
911 err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops);
913 pr_err("failed to register PPP device (%d)\n", err);
917 ppp_class = class_create(THIS_MODULE, "ppp");
918 if (IS_ERR(ppp_class)) {
919 err = PTR_ERR(ppp_class);
923 /* not a big deal if we fail here :-) */
924 device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, "ppp");
929 unregister_chrdev(PPP_MAJOR, "ppp");
931 unregister_pernet_device(&ppp_net_ops);
937 * Network interface unit routines.
940 ppp_start_xmit(struct sk_buff *skb, struct net_device *dev)
942 struct ppp *ppp = netdev_priv(dev);
946 npi = ethertype_to_npindex(ntohs(skb->protocol));
950 /* Drop, accept or reject the packet */
951 switch (ppp->npmode[npi]) {
955 /* it would be nice to have a way to tell the network
956 system to queue this one up for later. */
963 /* Put the 2-byte PPP protocol number on the front,
964 making sure there is room for the address and control fields. */
965 if (skb_cow_head(skb, PPP_HDRLEN))
968 pp = skb_push(skb, 2);
969 proto = npindex_to_proto[npi];
970 put_unaligned_be16(proto, pp);
972 skb_queue_tail(&ppp->file.xq, skb);
973 ppp_xmit_process(ppp);
978 ++dev->stats.tx_dropped;
983 ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
985 struct ppp *ppp = netdev_priv(dev);
987 void __user *addr = (void __user *) ifr->ifr_ifru.ifru_data;
988 struct ppp_stats stats;
989 struct ppp_comp_stats cstats;
994 ppp_get_stats(ppp, &stats);
995 if (copy_to_user(addr, &stats, sizeof(stats)))
1000 case SIOCGPPPCSTATS:
1001 memset(&cstats, 0, sizeof(cstats));
1003 ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c);
1005 ppp->rcomp->decomp_stat(ppp->rc_state, &cstats.d);
1006 if (copy_to_user(addr, &cstats, sizeof(cstats)))
1013 if (copy_to_user(addr, vers, strlen(vers) + 1))
1025 static const struct net_device_ops ppp_netdev_ops = {
1026 .ndo_start_xmit = ppp_start_xmit,
1027 .ndo_do_ioctl = ppp_net_ioctl,
1030 static void ppp_setup(struct net_device *dev)
1032 dev->netdev_ops = &ppp_netdev_ops;
1033 dev->hard_header_len = PPP_HDRLEN;
1036 dev->tx_queue_len = 3;
1037 dev->type = ARPHRD_PPP;
1038 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
1039 dev->features |= NETIF_F_NETNS_LOCAL;
1040 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1044 * Transmit-side routines.
1048 * Called to do any work queued up on the transmit side
1049 * that can now be done.
1052 ppp_xmit_process(struct ppp *ppp)
1054 struct sk_buff *skb;
1057 if (!ppp->closing) {
1059 while (!ppp->xmit_pending &&
1060 (skb = skb_dequeue(&ppp->file.xq)))
1061 ppp_send_frame(ppp, skb);
1062 /* If there's no work left to do, tell the core net
1063 code that we can accept some more. */
1064 if (!ppp->xmit_pending && !skb_peek(&ppp->file.xq))
1065 netif_wake_queue(ppp->dev);
1067 netif_stop_queue(ppp->dev);
1069 ppp_xmit_unlock(ppp);
1072 static inline struct sk_buff *
1073 pad_compress_skb(struct ppp *ppp, struct sk_buff *skb)
1075 struct sk_buff *new_skb;
1077 int new_skb_size = ppp->dev->mtu +
1078 ppp->xcomp->comp_extra + ppp->dev->hard_header_len;
1079 int compressor_skb_size = ppp->dev->mtu +
1080 ppp->xcomp->comp_extra + PPP_HDRLEN;
1081 new_skb = alloc_skb(new_skb_size, GFP_ATOMIC);
1083 if (net_ratelimit())
1084 netdev_err(ppp->dev, "PPP: no memory (comp pkt)\n");
1087 if (ppp->dev->hard_header_len > PPP_HDRLEN)
1088 skb_reserve(new_skb,
1089 ppp->dev->hard_header_len - PPP_HDRLEN);
1091 /* compressor still expects A/C bytes in hdr */
1092 len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2,
1093 new_skb->data, skb->len + 2,
1094 compressor_skb_size);
1095 if (len > 0 && (ppp->flags & SC_CCP_UP)) {
1099 skb_pull(skb, 2); /* pull off A/C bytes */
1100 } else if (len == 0) {
1101 /* didn't compress, or CCP not up yet */
1107 * MPPE requires that we do not send unencrypted
1108 * frames. The compressor will return -1 if we
1109 * should drop the frame. We cannot simply test
1110 * the compress_proto because MPPE and MPPC share
1113 if (net_ratelimit())
1114 netdev_err(ppp->dev, "ppp: compressor dropped pkt\n");
1123 * Compress and send a frame.
1124 * The caller should have locked the xmit path,
1125 * and xmit_pending should be 0.
1128 ppp_send_frame(struct ppp *ppp, struct sk_buff *skb)
1130 int proto = PPP_PROTO(skb);
1131 struct sk_buff *new_skb;
1135 if (proto < 0x8000) {
1136 #ifdef CONFIG_PPP_FILTER
1137 /* check if we should pass this packet */
1138 /* the filter instructions are constructed assuming
1139 a four-byte PPP header on each packet */
1140 *skb_push(skb, 2) = 1;
1141 if (ppp->pass_filter &&
1142 sk_run_filter(skb, ppp->pass_filter) == 0) {
1144 netdev_printk(KERN_DEBUG, ppp->dev,
1145 "PPP: outbound frame "
1150 /* if this packet passes the active filter, record the time */
1151 if (!(ppp->active_filter &&
1152 sk_run_filter(skb, ppp->active_filter) == 0))
1153 ppp->last_xmit = jiffies;
1156 /* for data packets, record the time */
1157 ppp->last_xmit = jiffies;
1158 #endif /* CONFIG_PPP_FILTER */
1161 ++ppp->dev->stats.tx_packets;
1162 ppp->dev->stats.tx_bytes += skb->len - 2;
1166 if (!ppp->vj || (ppp->flags & SC_COMP_TCP) == 0)
1168 /* try to do VJ TCP header compression */
1169 new_skb = alloc_skb(skb->len + ppp->dev->hard_header_len - 2,
1172 netdev_err(ppp->dev, "PPP: no memory (VJ comp pkt)\n");
1175 skb_reserve(new_skb, ppp->dev->hard_header_len - 2);
1177 len = slhc_compress(ppp->vj, cp, skb->len - 2,
1178 new_skb->data + 2, &cp,
1179 !(ppp->flags & SC_NO_TCP_CCID));
1180 if (cp == skb->data + 2) {
1181 /* didn't compress */
1184 if (cp[0] & SL_TYPE_COMPRESSED_TCP) {
1185 proto = PPP_VJC_COMP;
1186 cp[0] &= ~SL_TYPE_COMPRESSED_TCP;
1188 proto = PPP_VJC_UNCOMP;
1189 cp[0] = skb->data[2];
1193 cp = skb_put(skb, len + 2);
1200 /* peek at outbound CCP frames */
1201 ppp_ccp_peek(ppp, skb, 0);
1205 /* try to do packet compression */
1206 if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state &&
1207 proto != PPP_LCP && proto != PPP_CCP) {
1208 if (!(ppp->flags & SC_CCP_UP) && (ppp->flags & SC_MUST_COMP)) {
1209 if (net_ratelimit())
1210 netdev_err(ppp->dev,
1211 "ppp: compression required but "
1212 "down - pkt dropped.\n");
1215 skb = pad_compress_skb(ppp, skb);
1221 * If we are waiting for traffic (demand dialling),
1222 * queue it up for pppd to receive.
1224 if (ppp->flags & SC_LOOP_TRAFFIC) {
1225 if (ppp->file.rq.qlen > PPP_MAX_RQLEN)
1227 skb_queue_tail(&ppp->file.rq, skb);
1228 wake_up_interruptible(&ppp->file.rwait);
1232 ppp->xmit_pending = skb;
1238 ++ppp->dev->stats.tx_errors;
1242 * Try to send the frame in xmit_pending.
1243 * The caller should have the xmit path locked.
1246 ppp_push(struct ppp *ppp)
1248 struct list_head *list;
1249 struct channel *pch;
1250 struct sk_buff *skb = ppp->xmit_pending;
1255 list = &ppp->channels;
1256 if (list_empty(list)) {
1257 /* nowhere to send the packet, just drop it */
1258 ppp->xmit_pending = NULL;
1263 if ((ppp->flags & SC_MULTILINK) == 0) {
1264 /* not doing multilink: send it down the first channel */
1266 pch = list_entry(list, struct channel, clist);
1268 spin_lock_bh(&pch->downl);
1270 if (pch->chan->ops->start_xmit(pch->chan, skb))
1271 ppp->xmit_pending = NULL;
1273 /* channel got unregistered */
1275 ppp->xmit_pending = NULL;
1277 spin_unlock_bh(&pch->downl);
1281 #ifdef CONFIG_PPP_MULTILINK
1282 /* Multilink: fragment the packet over as many links
1283 as can take the packet at the moment. */
1284 if (!ppp_mp_explode(ppp, skb))
1286 #endif /* CONFIG_PPP_MULTILINK */
1288 ppp->xmit_pending = NULL;
1292 #ifdef CONFIG_PPP_MULTILINK
1293 static bool mp_protocol_compress __read_mostly = true;
1294 module_param(mp_protocol_compress, bool, S_IRUGO | S_IWUSR);
1295 MODULE_PARM_DESC(mp_protocol_compress,
1296 "compress protocol id in multilink fragments");
1299 * Divide a packet to be transmitted into fragments and
1300 * send them out the individual links.
1302 static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb)
1305 int i, bits, hdrlen, mtu;
1307 int navail, nfree, nzero;
1311 unsigned char *p, *q;
1312 struct list_head *list;
1313 struct channel *pch;
1314 struct sk_buff *frag;
1315 struct ppp_channel *chan;
1317 totspeed = 0; /*total bitrate of the bundle*/
1318 nfree = 0; /* # channels which have no packet already queued */
1319 navail = 0; /* total # of usable channels (not deregistered) */
1320 nzero = 0; /* number of channels with zero speed associated*/
1321 totfree = 0; /*total # of channels available and
1322 *having no queued packets before
1323 *starting the fragmentation*/
1325 hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
1327 list_for_each_entry(pch, &ppp->channels, clist) {
1331 pch->speed = pch->chan->speed;
1336 if (skb_queue_empty(&pch->file.xq) ||
1338 if (pch->speed == 0)
1341 totspeed += pch->speed;
1347 if (!pch->had_frag && i < ppp->nxchan)
1353 * Don't start sending this packet unless at least half of
1354 * the channels are free. This gives much better TCP
1355 * performance if we have a lot of channels.
1357 if (nfree == 0 || nfree < navail / 2)
1358 return 0; /* can't take now, leave it in xmit_pending */
1360 /* Do protocol field compression */
1363 if (*p == 0 && mp_protocol_compress) {
1369 nbigger = len % nfree;
1371 /* skip to the channel after the one we last used
1372 and start at that one */
1373 list = &ppp->channels;
1374 for (i = 0; i < ppp->nxchan; ++i) {
1376 if (list == &ppp->channels) {
1382 /* create a fragment for each channel */
1386 if (list == &ppp->channels) {
1390 pch = list_entry(list, struct channel, clist);
1396 * Skip this channel if it has a fragment pending already and
1397 * we haven't given a fragment to all of the free channels.
1399 if (pch->avail == 1) {
1406 /* check the channel's mtu and whether it is still attached. */
1407 spin_lock_bh(&pch->downl);
1408 if (pch->chan == NULL) {
1409 /* can't use this channel, it's being deregistered */
1410 if (pch->speed == 0)
1413 totspeed -= pch->speed;
1415 spin_unlock_bh(&pch->downl);
1426 *if the channel speed is not set divide
1427 *the packet evenly among the free channels;
1428 *otherwise divide it according to the speed
1429 *of the channel we are going to transmit on
1433 if (pch->speed == 0) {
1440 flen = (((totfree - nzero)*(totlen + hdrlen*totfree)) /
1441 ((totspeed*totfree)/pch->speed)) - hdrlen;
1443 flen += ((totfree - nzero)*pch->speed)/totspeed;
1444 nbigger -= ((totfree - nzero)*pch->speed)/
1452 *check if we are on the last channel or
1453 *we exceded the length of the data to
1456 if ((nfree <= 0) || (flen > len))
1459 *it is not worth to tx on slow channels:
1460 *in that case from the resulting flen according to the
1461 *above formula will be equal or less than zero.
1462 *Skip the channel in this case
1466 spin_unlock_bh(&pch->downl);
1471 * hdrlen includes the 2-byte PPP protocol field, but the
1472 * MTU counts only the payload excluding the protocol field.
1473 * (RFC1661 Section 2)
1475 mtu = pch->chan->mtu - (hdrlen - 2);
1482 frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
1485 q = skb_put(frag, flen + hdrlen);
1487 /* make the MP header */
1488 put_unaligned_be16(PPP_MP, q);
1489 if (ppp->flags & SC_MP_XSHORTSEQ) {
1490 q[2] = bits + ((ppp->nxseq >> 8) & 0xf);
1494 q[3] = ppp->nxseq >> 16;
1495 q[4] = ppp->nxseq >> 8;
1499 memcpy(q + hdrlen, p, flen);
1501 /* try to send it down the channel */
1503 if (!skb_queue_empty(&pch->file.xq) ||
1504 !chan->ops->start_xmit(chan, frag))
1505 skb_queue_tail(&pch->file.xq, frag);
1511 spin_unlock_bh(&pch->downl);
1518 spin_unlock_bh(&pch->downl);
1520 netdev_err(ppp->dev, "PPP: no memory (fragment)\n");
1521 ++ppp->dev->stats.tx_errors;
1523 return 1; /* abandon the frame */
1525 #endif /* CONFIG_PPP_MULTILINK */
1528 * Try to send data out on a channel.
1531 ppp_channel_push(struct channel *pch)
1533 struct sk_buff *skb;
1536 spin_lock_bh(&pch->downl);
1538 while (!skb_queue_empty(&pch->file.xq)) {
1539 skb = skb_dequeue(&pch->file.xq);
1540 if (!pch->chan->ops->start_xmit(pch->chan, skb)) {
1541 /* put the packet back and try again later */
1542 skb_queue_head(&pch->file.xq, skb);
1547 /* channel got deregistered */
1548 skb_queue_purge(&pch->file.xq);
1550 spin_unlock_bh(&pch->downl);
1551 /* see if there is anything from the attached unit to be sent */
1552 if (skb_queue_empty(&pch->file.xq)) {
1553 read_lock_bh(&pch->upl);
1556 ppp_xmit_process(ppp);
1557 read_unlock_bh(&pch->upl);
1562 * Receive-side routines.
1565 struct ppp_mp_skb_parm {
1569 #define PPP_MP_CB(skb) ((struct ppp_mp_skb_parm *)((skb)->cb))
1572 ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1576 ppp_receive_frame(ppp, skb, pch);
1579 ppp_recv_unlock(ppp);
1583 ppp_input(struct ppp_channel *chan, struct sk_buff *skb)
1585 struct channel *pch = chan->ppp;
1593 read_lock_bh(&pch->upl);
1594 if (!pskb_may_pull(skb, 2)) {
1597 ++pch->ppp->dev->stats.rx_length_errors;
1598 ppp_receive_error(pch->ppp);
1603 proto = PPP_PROTO(skb);
1604 if (!pch->ppp || proto >= 0xc000 || proto == PPP_CCPFRAG) {
1605 /* put it on the channel queue */
1606 skb_queue_tail(&pch->file.rq, skb);
1607 /* drop old frames if queue too long */
1608 while (pch->file.rq.qlen > PPP_MAX_RQLEN &&
1609 (skb = skb_dequeue(&pch->file.rq)))
1611 wake_up_interruptible(&pch->file.rwait);
1613 ppp_do_recv(pch->ppp, skb, pch);
1617 read_unlock_bh(&pch->upl);
1620 /* Put a 0-length skb in the receive queue as an error indication */
1622 ppp_input_error(struct ppp_channel *chan, int code)
1624 struct channel *pch = chan->ppp;
1625 struct sk_buff *skb;
1630 read_lock_bh(&pch->upl);
1632 skb = alloc_skb(0, GFP_ATOMIC);
1634 skb->len = 0; /* probably unnecessary */
1636 ppp_do_recv(pch->ppp, skb, pch);
1639 read_unlock_bh(&pch->upl);
1643 * We come in here to process a received frame.
1644 * The receive side of the ppp unit is locked.
1647 ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1649 /* note: a 0-length skb is used as an error indication */
1651 #ifdef CONFIG_PPP_MULTILINK
1652 /* XXX do channel-level decompression here */
1653 if (PPP_PROTO(skb) == PPP_MP)
1654 ppp_receive_mp_frame(ppp, skb, pch);
1656 #endif /* CONFIG_PPP_MULTILINK */
1657 ppp_receive_nonmp_frame(ppp, skb);
1660 ppp_receive_error(ppp);
1665 ppp_receive_error(struct ppp *ppp)
1667 ++ppp->dev->stats.rx_errors;
1673 ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb)
1676 int proto, len, npi;
1679 * Decompress the frame, if compressed.
1680 * Note that some decompressors need to see uncompressed frames
1681 * that come in as well as compressed frames.
1683 if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN) &&
1684 (ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0)
1685 skb = ppp_decompress_frame(ppp, skb);
1687 if (ppp->flags & SC_MUST_COMP && ppp->rstate & SC_DC_FERROR)
1690 proto = PPP_PROTO(skb);
1693 /* decompress VJ compressed packets */
1694 if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP))
1697 if (skb_tailroom(skb) < 124 || skb_cloned(skb)) {
1698 /* copy to a new sk_buff with more tailroom */
1699 ns = dev_alloc_skb(skb->len + 128);
1701 netdev_err(ppp->dev, "PPP: no memory "
1706 skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len);
1711 skb->ip_summed = CHECKSUM_NONE;
1713 len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2);
1715 netdev_printk(KERN_DEBUG, ppp->dev,
1716 "PPP: VJ decompression error\n");
1721 skb_put(skb, len - skb->len);
1722 else if (len < skb->len)
1727 case PPP_VJC_UNCOMP:
1728 if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP))
1731 /* Until we fix the decompressor need to make sure
1732 * data portion is linear.
1734 if (!pskb_may_pull(skb, skb->len))
1737 if (slhc_remember(ppp->vj, skb->data + 2, skb->len - 2) <= 0) {
1738 netdev_err(ppp->dev, "PPP: VJ uncompressed error\n");
1745 ppp_ccp_peek(ppp, skb, 1);
1749 ++ppp->dev->stats.rx_packets;
1750 ppp->dev->stats.rx_bytes += skb->len - 2;
1752 npi = proto_to_npindex(proto);
1754 /* control or unknown frame - pass it to pppd */
1755 skb_queue_tail(&ppp->file.rq, skb);
1756 /* limit queue length by dropping old frames */
1757 while (ppp->file.rq.qlen > PPP_MAX_RQLEN &&
1758 (skb = skb_dequeue(&ppp->file.rq)))
1760 /* wake up any process polling or blocking on read */
1761 wake_up_interruptible(&ppp->file.rwait);
1764 /* network protocol frame - give it to the kernel */
1766 #ifdef CONFIG_PPP_FILTER
1767 /* check if the packet passes the pass and active filters */
1768 /* the filter instructions are constructed assuming
1769 a four-byte PPP header on each packet */
1770 if (ppp->pass_filter || ppp->active_filter) {
1771 if (skb_cloned(skb) &&
1772 pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
1775 *skb_push(skb, 2) = 0;
1776 if (ppp->pass_filter &&
1777 sk_run_filter(skb, ppp->pass_filter) == 0) {
1779 netdev_printk(KERN_DEBUG, ppp->dev,
1780 "PPP: inbound frame "
1785 if (!(ppp->active_filter &&
1786 sk_run_filter(skb, ppp->active_filter) == 0))
1787 ppp->last_recv = jiffies;
1790 #endif /* CONFIG_PPP_FILTER */
1791 ppp->last_recv = jiffies;
1793 if ((ppp->dev->flags & IFF_UP) == 0 ||
1794 ppp->npmode[npi] != NPMODE_PASS) {
1797 /* chop off protocol */
1798 skb_pull_rcsum(skb, 2);
1799 skb->dev = ppp->dev;
1800 skb->protocol = htons(npindex_to_ethertype[npi]);
1801 skb_reset_mac_header(skb);
1809 ppp_receive_error(ppp);
1812 static struct sk_buff *
1813 ppp_decompress_frame(struct ppp *ppp, struct sk_buff *skb)
1815 int proto = PPP_PROTO(skb);
1819 /* Until we fix all the decompressor's need to make sure
1820 * data portion is linear.
1822 if (!pskb_may_pull(skb, skb->len))
1825 if (proto == PPP_COMP) {
1828 switch(ppp->rcomp->compress_proto) {
1830 obuff_size = ppp->mru + PPP_HDRLEN + 1;
1833 obuff_size = ppp->mru + PPP_HDRLEN;
1837 ns = dev_alloc_skb(obuff_size);
1839 netdev_err(ppp->dev, "ppp_decompress_frame: "
1843 /* the decompressor still expects the A/C bytes in the hdr */
1844 len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2,
1845 skb->len + 2, ns->data, obuff_size);
1847 /* Pass the compressed frame to pppd as an
1848 error indication. */
1849 if (len == DECOMP_FATALERROR)
1850 ppp->rstate |= SC_DC_FERROR;
1858 skb_pull(skb, 2); /* pull off the A/C bytes */
1861 /* Uncompressed frame - pass to decompressor so it
1862 can update its dictionary if necessary. */
1863 if (ppp->rcomp->incomp)
1864 ppp->rcomp->incomp(ppp->rc_state, skb->data - 2,
1871 ppp->rstate |= SC_DC_ERROR;
1872 ppp_receive_error(ppp);
1876 #ifdef CONFIG_PPP_MULTILINK
1878 * Receive a multilink frame.
1879 * We put it on the reconstruction queue and then pull off
1880 * as many completed frames as we can.
1883 ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1887 int mphdrlen = (ppp->flags & SC_MP_SHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
1889 if (!pskb_may_pull(skb, mphdrlen + 1) || ppp->mrru == 0)
1890 goto err; /* no good, throw it away */
1892 /* Decode sequence number and begin/end bits */
1893 if (ppp->flags & SC_MP_SHORTSEQ) {
1894 seq = ((skb->data[2] & 0x0f) << 8) | skb->data[3];
1897 seq = (skb->data[3] << 16) | (skb->data[4] << 8)| skb->data[5];
1900 PPP_MP_CB(skb)->BEbits = skb->data[2];
1901 skb_pull(skb, mphdrlen); /* pull off PPP and MP headers */
1904 * Do protocol ID decompression on the first fragment of each packet.
1906 if ((PPP_MP_CB(skb)->BEbits & B) && (skb->data[0] & 1))
1907 *skb_push(skb, 1) = 0;
1910 * Expand sequence number to 32 bits, making it as close
1911 * as possible to ppp->minseq.
1913 seq |= ppp->minseq & ~mask;
1914 if ((int)(ppp->minseq - seq) > (int)(mask >> 1))
1916 else if ((int)(seq - ppp->minseq) > (int)(mask >> 1))
1917 seq -= mask + 1; /* should never happen */
1918 PPP_MP_CB(skb)->sequence = seq;
1922 * If this packet comes before the next one we were expecting,
1925 if (seq_before(seq, ppp->nextseq)) {
1927 ++ppp->dev->stats.rx_dropped;
1928 ppp_receive_error(ppp);
1933 * Reevaluate minseq, the minimum over all channels of the
1934 * last sequence number received on each channel. Because of
1935 * the increasing sequence number rule, we know that any fragment
1936 * before `minseq' which hasn't arrived is never going to arrive.
1937 * The list of channels can't change because we have the receive
1938 * side of the ppp unit locked.
1940 list_for_each_entry(ch, &ppp->channels, clist) {
1941 if (seq_before(ch->lastseq, seq))
1944 if (seq_before(ppp->minseq, seq))
1947 /* Put the fragment on the reconstruction queue */
1948 ppp_mp_insert(ppp, skb);
1950 /* If the queue is getting long, don't wait any longer for packets
1951 before the start of the queue. */
1952 if (skb_queue_len(&ppp->mrq) >= PPP_MP_MAX_QLEN) {
1953 struct sk_buff *mskb = skb_peek(&ppp->mrq);
1954 if (seq_before(ppp->minseq, PPP_MP_CB(mskb)->sequence))
1955 ppp->minseq = PPP_MP_CB(mskb)->sequence;
1958 /* Pull completed packets off the queue and receive them. */
1959 while ((skb = ppp_mp_reconstruct(ppp))) {
1960 if (pskb_may_pull(skb, 2))
1961 ppp_receive_nonmp_frame(ppp, skb);
1963 ++ppp->dev->stats.rx_length_errors;
1965 ppp_receive_error(ppp);
1973 ppp_receive_error(ppp);
1977 * Insert a fragment on the MP reconstruction queue.
1978 * The queue is ordered by increasing sequence number.
1981 ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb)
1984 struct sk_buff_head *list = &ppp->mrq;
1985 u32 seq = PPP_MP_CB(skb)->sequence;
1987 /* N.B. we don't need to lock the list lock because we have the
1988 ppp unit receive-side lock. */
1989 skb_queue_walk(list, p) {
1990 if (seq_before(seq, PPP_MP_CB(p)->sequence))
1993 __skb_queue_before(list, p, skb);
1997 * Reconstruct a packet from the MP fragment queue.
1998 * We go through increasing sequence numbers until we find a
1999 * complete packet, or we get to the sequence number for a fragment
2000 * which hasn't arrived but might still do so.
2002 static struct sk_buff *
2003 ppp_mp_reconstruct(struct ppp *ppp)
2005 u32 seq = ppp->nextseq;
2006 u32 minseq = ppp->minseq;
2007 struct sk_buff_head *list = &ppp->mrq;
2008 struct sk_buff *p, *tmp;
2009 struct sk_buff *head, *tail;
2010 struct sk_buff *skb = NULL;
2011 int lost = 0, len = 0;
2013 if (ppp->mrru == 0) /* do nothing until mrru is set */
2017 skb_queue_walk_safe(list, p, tmp) {
2019 if (seq_before(PPP_MP_CB(p)->sequence, seq)) {
2020 /* this can't happen, anyway ignore the skb */
2021 netdev_err(ppp->dev, "ppp_mp_reconstruct bad "
2023 PPP_MP_CB(p)->sequence, seq);
2024 __skb_unlink(p, list);
2028 if (PPP_MP_CB(p)->sequence != seq) {
2030 /* Fragment `seq' is missing. If it is after
2031 minseq, it might arrive later, so stop here. */
2032 if (seq_after(seq, minseq))
2034 /* Fragment `seq' is lost, keep going. */
2037 seq = seq_before(minseq, PPP_MP_CB(p)->sequence)?
2038 minseq + 1: PPP_MP_CB(p)->sequence;
2041 netdev_printk(KERN_DEBUG, ppp->dev,
2042 "lost frag %u..%u\n",
2049 * At this point we know that all the fragments from
2050 * ppp->nextseq to seq are either present or lost.
2051 * Also, there are no complete packets in the queue
2052 * that have no missing fragments and end before this
2056 /* B bit set indicates this fragment starts a packet */
2057 if (PPP_MP_CB(p)->BEbits & B) {
2065 /* Got a complete packet yet? */
2066 if (lost == 0 && (PPP_MP_CB(p)->BEbits & E) &&
2067 (PPP_MP_CB(head)->BEbits & B)) {
2068 if (len > ppp->mrru + 2) {
2069 ++ppp->dev->stats.rx_length_errors;
2070 netdev_printk(KERN_DEBUG, ppp->dev,
2071 "PPP: reconstructed packet"
2072 " is too long (%d)\n", len);
2077 ppp->nextseq = seq + 1;
2081 * If this is the ending fragment of a packet,
2082 * and we haven't found a complete valid packet yet,
2083 * we can discard up to and including this fragment.
2085 if (PPP_MP_CB(p)->BEbits & E) {
2086 struct sk_buff *tmp2;
2088 skb_queue_reverse_walk_from_safe(list, p, tmp2) {
2090 netdev_printk(KERN_DEBUG, ppp->dev,
2091 "discarding frag %u\n",
2092 PPP_MP_CB(p)->sequence);
2093 __skb_unlink(p, list);
2096 head = skb_peek(list);
2103 /* If we have a complete packet, copy it all into one skb. */
2105 /* If we have discarded any fragments,
2106 signal a receive error. */
2107 if (PPP_MP_CB(head)->sequence != ppp->nextseq) {
2108 skb_queue_walk_safe(list, p, tmp) {
2112 netdev_printk(KERN_DEBUG, ppp->dev,
2113 "discarding frag %u\n",
2114 PPP_MP_CB(p)->sequence);
2115 __skb_unlink(p, list);
2120 netdev_printk(KERN_DEBUG, ppp->dev,
2121 " missed pkts %u..%u\n",
2123 PPP_MP_CB(head)->sequence-1);
2124 ++ppp->dev->stats.rx_dropped;
2125 ppp_receive_error(ppp);
2130 struct sk_buff **fragpp = &skb_shinfo(skb)->frag_list;
2131 p = skb_queue_next(list, head);
2132 __skb_unlink(skb, list);
2133 skb_queue_walk_from_safe(list, p, tmp) {
2134 __skb_unlink(p, list);
2140 skb->data_len += p->len;
2141 skb->truesize += p->len;
2147 __skb_unlink(skb, list);
2150 ppp->nextseq = PPP_MP_CB(tail)->sequence + 1;
2155 #endif /* CONFIG_PPP_MULTILINK */
2158 * Channel interface.
2161 /* Create a new, unattached ppp channel. */
2162 int ppp_register_channel(struct ppp_channel *chan)
2164 return ppp_register_net_channel(current->nsproxy->net_ns, chan);
2167 /* Create a new, unattached ppp channel for specified net. */
2168 int ppp_register_net_channel(struct net *net, struct ppp_channel *chan)
2170 struct channel *pch;
2173 pch = kzalloc(sizeof(struct channel), GFP_KERNEL);
2177 pn = ppp_pernet(net);
2181 pch->chan_net = get_net(net);
2183 init_ppp_file(&pch->file, CHANNEL);
2184 pch->file.hdrlen = chan->hdrlen;
2185 #ifdef CONFIG_PPP_MULTILINK
2187 #endif /* CONFIG_PPP_MULTILINK */
2188 init_rwsem(&pch->chan_sem);
2189 spin_lock_init(&pch->downl);
2190 rwlock_init(&pch->upl);
2192 spin_lock_bh(&pn->all_channels_lock);
2193 pch->file.index = ++pn->last_channel_index;
2194 list_add(&pch->list, &pn->new_channels);
2195 atomic_inc(&channel_count);
2196 spin_unlock_bh(&pn->all_channels_lock);
2202 * Return the index of a channel.
2204 int ppp_channel_index(struct ppp_channel *chan)
2206 struct channel *pch = chan->ppp;
2209 return pch->file.index;
2214 * Return the PPP unit number to which a channel is connected.
2216 int ppp_unit_number(struct ppp_channel *chan)
2218 struct channel *pch = chan->ppp;
2222 read_lock_bh(&pch->upl);
2224 unit = pch->ppp->file.index;
2225 read_unlock_bh(&pch->upl);
2231 * Return the PPP device interface name of a channel.
2233 char *ppp_dev_name(struct ppp_channel *chan)
2235 struct channel *pch = chan->ppp;
2239 read_lock_bh(&pch->upl);
2240 if (pch->ppp && pch->ppp->dev)
2241 name = pch->ppp->dev->name;
2242 read_unlock_bh(&pch->upl);
2249 * Disconnect a channel from the generic layer.
2250 * This must be called in process context.
2253 ppp_unregister_channel(struct ppp_channel *chan)
2255 struct channel *pch = chan->ppp;
2259 return; /* should never happen */
2264 * This ensures that we have returned from any calls into the
2265 * the channel's start_xmit or ioctl routine before we proceed.
2267 down_write(&pch->chan_sem);
2268 spin_lock_bh(&pch->downl);
2270 spin_unlock_bh(&pch->downl);
2271 up_write(&pch->chan_sem);
2272 ppp_disconnect_channel(pch);
2274 pn = ppp_pernet(pch->chan_net);
2275 spin_lock_bh(&pn->all_channels_lock);
2276 list_del(&pch->list);
2277 spin_unlock_bh(&pn->all_channels_lock);
2280 wake_up_interruptible(&pch->file.rwait);
2281 if (atomic_dec_and_test(&pch->file.refcnt))
2282 ppp_destroy_channel(pch);
2286 * Callback from a channel when it can accept more to transmit.
2287 * This should be called at BH/softirq level, not interrupt level.
2290 ppp_output_wakeup(struct ppp_channel *chan)
2292 struct channel *pch = chan->ppp;
2296 ppp_channel_push(pch);
2300 * Compression control.
2303 /* Process the PPPIOCSCOMPRESS ioctl. */
2305 ppp_set_compress(struct ppp *ppp, unsigned long arg)
2308 struct compressor *cp, *ocomp;
2309 struct ppp_option_data data;
2310 void *state, *ostate;
2311 unsigned char ccp_option[CCP_MAX_OPTION_LENGTH];
2314 if (copy_from_user(&data, (void __user *) arg, sizeof(data)) ||
2315 (data.length <= CCP_MAX_OPTION_LENGTH &&
2316 copy_from_user(ccp_option, (void __user *) data.ptr, data.length)))
2319 if (data.length > CCP_MAX_OPTION_LENGTH ||
2320 ccp_option[1] < 2 || ccp_option[1] > data.length)
2323 cp = try_then_request_module(
2324 find_compressor(ccp_option[0]),
2325 "ppp-compress-%d", ccp_option[0]);
2330 if (data.transmit) {
2331 state = cp->comp_alloc(ccp_option, data.length);
2334 ppp->xstate &= ~SC_COMP_RUN;
2336 ostate = ppp->xc_state;
2338 ppp->xc_state = state;
2339 ppp_xmit_unlock(ppp);
2341 ocomp->comp_free(ostate);
2342 module_put(ocomp->owner);
2346 module_put(cp->owner);
2349 state = cp->decomp_alloc(ccp_option, data.length);
2352 ppp->rstate &= ~SC_DECOMP_RUN;
2354 ostate = ppp->rc_state;
2356 ppp->rc_state = state;
2357 ppp_recv_unlock(ppp);
2359 ocomp->decomp_free(ostate);
2360 module_put(ocomp->owner);
2364 module_put(cp->owner);
2372 * Look at a CCP packet and update our state accordingly.
2373 * We assume the caller has the xmit or recv path locked.
2376 ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound)
2381 if (!pskb_may_pull(skb, CCP_HDRLEN + 2))
2382 return; /* no header */
2385 switch (CCP_CODE(dp)) {
2388 /* A ConfReq starts negotiation of compression
2389 * in one direction of transmission,
2390 * and hence brings it down...but which way?
2393 * A ConfReq indicates what the sender would like to receive
2396 /* He is proposing what I should send */
2397 ppp->xstate &= ~SC_COMP_RUN;
2399 /* I am proposing to what he should send */
2400 ppp->rstate &= ~SC_DECOMP_RUN;
2407 * CCP is going down, both directions of transmission
2409 ppp->rstate &= ~SC_DECOMP_RUN;
2410 ppp->xstate &= ~SC_COMP_RUN;
2414 if ((ppp->flags & (SC_CCP_OPEN | SC_CCP_UP)) != SC_CCP_OPEN)
2416 len = CCP_LENGTH(dp);
2417 if (!pskb_may_pull(skb, len + 2))
2418 return; /* too short */
2421 if (len < CCP_OPT_MINLEN || len < CCP_OPT_LENGTH(dp))
2424 /* we will start receiving compressed packets */
2427 if (ppp->rcomp->decomp_init(ppp->rc_state, dp, len,
2428 ppp->file.index, 0, ppp->mru, ppp->debug)) {
2429 ppp->rstate |= SC_DECOMP_RUN;
2430 ppp->rstate &= ~(SC_DC_ERROR | SC_DC_FERROR);
2433 /* we will soon start sending compressed packets */
2436 if (ppp->xcomp->comp_init(ppp->xc_state, dp, len,
2437 ppp->file.index, 0, ppp->debug))
2438 ppp->xstate |= SC_COMP_RUN;
2443 /* reset the [de]compressor */
2444 if ((ppp->flags & SC_CCP_UP) == 0)
2447 if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN)) {
2448 ppp->rcomp->decomp_reset(ppp->rc_state);
2449 ppp->rstate &= ~SC_DC_ERROR;
2452 if (ppp->xc_state && (ppp->xstate & SC_COMP_RUN))
2453 ppp->xcomp->comp_reset(ppp->xc_state);
2459 /* Free up compression resources. */
2461 ppp_ccp_closed(struct ppp *ppp)
2463 void *xstate, *rstate;
2464 struct compressor *xcomp, *rcomp;
2467 ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP);
2470 xstate = ppp->xc_state;
2471 ppp->xc_state = NULL;
2474 rstate = ppp->rc_state;
2475 ppp->rc_state = NULL;
2479 xcomp->comp_free(xstate);
2480 module_put(xcomp->owner);
2483 rcomp->decomp_free(rstate);
2484 module_put(rcomp->owner);
2488 /* List of compressors. */
2489 static LIST_HEAD(compressor_list);
2490 static DEFINE_SPINLOCK(compressor_list_lock);
2492 struct compressor_entry {
2493 struct list_head list;
2494 struct compressor *comp;
2497 static struct compressor_entry *
2498 find_comp_entry(int proto)
2500 struct compressor_entry *ce;
2502 list_for_each_entry(ce, &compressor_list, list) {
2503 if (ce->comp->compress_proto == proto)
2509 /* Register a compressor */
2511 ppp_register_compressor(struct compressor *cp)
2513 struct compressor_entry *ce;
2515 spin_lock(&compressor_list_lock);
2517 if (find_comp_entry(cp->compress_proto))
2520 ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC);
2525 list_add(&ce->list, &compressor_list);
2527 spin_unlock(&compressor_list_lock);
2531 /* Unregister a compressor */
2533 ppp_unregister_compressor(struct compressor *cp)
2535 struct compressor_entry *ce;
2537 spin_lock(&compressor_list_lock);
2538 ce = find_comp_entry(cp->compress_proto);
2539 if (ce && ce->comp == cp) {
2540 list_del(&ce->list);
2543 spin_unlock(&compressor_list_lock);
2546 /* Find a compressor. */
2547 static struct compressor *
2548 find_compressor(int type)
2550 struct compressor_entry *ce;
2551 struct compressor *cp = NULL;
2553 spin_lock(&compressor_list_lock);
2554 ce = find_comp_entry(type);
2557 if (!try_module_get(cp->owner))
2560 spin_unlock(&compressor_list_lock);
2565 * Miscelleneous stuff.
2569 ppp_get_stats(struct ppp *ppp, struct ppp_stats *st)
2571 struct slcompress *vj = ppp->vj;
2573 memset(st, 0, sizeof(*st));
2574 st->p.ppp_ipackets = ppp->dev->stats.rx_packets;
2575 st->p.ppp_ierrors = ppp->dev->stats.rx_errors;
2576 st->p.ppp_ibytes = ppp->dev->stats.rx_bytes;
2577 st->p.ppp_opackets = ppp->dev->stats.tx_packets;
2578 st->p.ppp_oerrors = ppp->dev->stats.tx_errors;
2579 st->p.ppp_obytes = ppp->dev->stats.tx_bytes;
2582 st->vj.vjs_packets = vj->sls_o_compressed + vj->sls_o_uncompressed;
2583 st->vj.vjs_compressed = vj->sls_o_compressed;
2584 st->vj.vjs_searches = vj->sls_o_searches;
2585 st->vj.vjs_misses = vj->sls_o_misses;
2586 st->vj.vjs_errorin = vj->sls_i_error;
2587 st->vj.vjs_tossed = vj->sls_i_tossed;
2588 st->vj.vjs_uncompressedin = vj->sls_i_uncompressed;
2589 st->vj.vjs_compressedin = vj->sls_i_compressed;
2593 * Stuff for handling the lists of ppp units and channels
2594 * and for initialization.
2598 * Create a new ppp interface unit. Fails if it can't allocate memory
2599 * or if there is already a unit with the requested number.
2600 * unit == -1 means allocate a new number.
2603 ppp_create_interface(struct net *net, int unit, int *retp)
2607 struct net_device *dev = NULL;
2611 dev = alloc_netdev(sizeof(struct ppp), "", ppp_setup);
2615 pn = ppp_pernet(net);
2617 ppp = netdev_priv(dev);
2620 init_ppp_file(&ppp->file, INTERFACE);
2621 ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */
2622 for (i = 0; i < NUM_NP; ++i)
2623 ppp->npmode[i] = NPMODE_PASS;
2624 INIT_LIST_HEAD(&ppp->channels);
2625 spin_lock_init(&ppp->rlock);
2626 spin_lock_init(&ppp->wlock);
2627 #ifdef CONFIG_PPP_MULTILINK
2629 skb_queue_head_init(&ppp->mrq);
2630 #endif /* CONFIG_PPP_MULTILINK */
2633 * drum roll: don't forget to set
2634 * the net device is belong to
2636 dev_net_set(dev, net);
2638 mutex_lock(&pn->all_ppp_mutex);
2641 unit = unit_get(&pn->units_idr, ppp);
2648 if (unit_find(&pn->units_idr, unit))
2649 goto out2; /* unit already exists */
2651 * if caller need a specified unit number
2652 * lets try to satisfy him, otherwise --
2653 * he should better ask us for new unit number
2655 * NOTE: yes I know that returning EEXIST it's not
2656 * fair but at least pppd will ask us to allocate
2657 * new unit in this case so user is happy :)
2659 unit = unit_set(&pn->units_idr, ppp, unit);
2664 /* Initialize the new ppp unit */
2665 ppp->file.index = unit;
2666 sprintf(dev->name, "ppp%d", unit);
2668 ret = register_netdev(dev);
2670 unit_put(&pn->units_idr, unit);
2671 netdev_err(ppp->dev, "PPP: couldn't register device %s (%d)\n",
2678 atomic_inc(&ppp_unit_count);
2679 mutex_unlock(&pn->all_ppp_mutex);
2685 mutex_unlock(&pn->all_ppp_mutex);
2693 * Initialize a ppp_file structure.
2696 init_ppp_file(struct ppp_file *pf, int kind)
2699 skb_queue_head_init(&pf->xq);
2700 skb_queue_head_init(&pf->rq);
2701 atomic_set(&pf->refcnt, 1);
2702 init_waitqueue_head(&pf->rwait);
2706 * Take down a ppp interface unit - called when the owning file
2707 * (the one that created the unit) is closed or detached.
2709 static void ppp_shutdown_interface(struct ppp *ppp)
2713 pn = ppp_pernet(ppp->ppp_net);
2714 mutex_lock(&pn->all_ppp_mutex);
2716 /* This will call dev_close() for us. */
2718 if (!ppp->closing) {
2721 unregister_netdev(ppp->dev);
2722 unit_put(&pn->units_idr, ppp->file.index);
2728 wake_up_interruptible(&ppp->file.rwait);
2730 mutex_unlock(&pn->all_ppp_mutex);
2734 * Free the memory used by a ppp unit. This is only called once
2735 * there are no channels connected to the unit and no file structs
2736 * that reference the unit.
2738 static void ppp_destroy_interface(struct ppp *ppp)
2740 atomic_dec(&ppp_unit_count);
2742 if (!ppp->file.dead || ppp->n_channels) {
2743 /* "can't happen" */
2744 netdev_err(ppp->dev, "ppp: destroying ppp struct %p "
2745 "but dead=%d n_channels=%d !\n",
2746 ppp, ppp->file.dead, ppp->n_channels);
2750 ppp_ccp_closed(ppp);
2755 skb_queue_purge(&ppp->file.xq);
2756 skb_queue_purge(&ppp->file.rq);
2757 #ifdef CONFIG_PPP_MULTILINK
2758 skb_queue_purge(&ppp->mrq);
2759 #endif /* CONFIG_PPP_MULTILINK */
2760 #ifdef CONFIG_PPP_FILTER
2761 kfree(ppp->pass_filter);
2762 ppp->pass_filter = NULL;
2763 kfree(ppp->active_filter);
2764 ppp->active_filter = NULL;
2765 #endif /* CONFIG_PPP_FILTER */
2767 kfree_skb(ppp->xmit_pending);
2769 free_netdev(ppp->dev);
2773 * Locate an existing ppp unit.
2774 * The caller should have locked the all_ppp_mutex.
2777 ppp_find_unit(struct ppp_net *pn, int unit)
2779 return unit_find(&pn->units_idr, unit);
2783 * Locate an existing ppp channel.
2784 * The caller should have locked the all_channels_lock.
2785 * First we look in the new_channels list, then in the
2786 * all_channels list. If found in the new_channels list,
2787 * we move it to the all_channels list. This is for speed
2788 * when we have a lot of channels in use.
2790 static struct channel *
2791 ppp_find_channel(struct ppp_net *pn, int unit)
2793 struct channel *pch;
2795 list_for_each_entry(pch, &pn->new_channels, list) {
2796 if (pch->file.index == unit) {
2797 list_move(&pch->list, &pn->all_channels);
2802 list_for_each_entry(pch, &pn->all_channels, list) {
2803 if (pch->file.index == unit)
2811 * Connect a PPP channel to a PPP interface unit.
2814 ppp_connect_channel(struct channel *pch, int unit)
2821 pn = ppp_pernet(pch->chan_net);
2823 mutex_lock(&pn->all_ppp_mutex);
2824 ppp = ppp_find_unit(pn, unit);
2827 write_lock_bh(&pch->upl);
2833 if (pch->file.hdrlen > ppp->file.hdrlen)
2834 ppp->file.hdrlen = pch->file.hdrlen;
2835 hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */
2836 if (hdrlen > ppp->dev->hard_header_len)
2837 ppp->dev->hard_header_len = hdrlen;
2838 list_add_tail(&pch->clist, &ppp->channels);
2841 atomic_inc(&ppp->file.refcnt);
2846 write_unlock_bh(&pch->upl);
2848 mutex_unlock(&pn->all_ppp_mutex);
2853 * Disconnect a channel from its ppp unit.
2856 ppp_disconnect_channel(struct channel *pch)
2861 write_lock_bh(&pch->upl);
2864 write_unlock_bh(&pch->upl);
2866 /* remove it from the ppp unit's list */
2868 list_del(&pch->clist);
2869 if (--ppp->n_channels == 0)
2870 wake_up_interruptible(&ppp->file.rwait);
2872 if (atomic_dec_and_test(&ppp->file.refcnt))
2873 ppp_destroy_interface(ppp);
2880 * Free up the resources used by a ppp channel.
2882 static void ppp_destroy_channel(struct channel *pch)
2884 put_net(pch->chan_net);
2885 pch->chan_net = NULL;
2887 atomic_dec(&channel_count);
2889 if (!pch->file.dead) {
2890 /* "can't happen" */
2891 pr_err("ppp: destroying undead channel %p !\n", pch);
2894 skb_queue_purge(&pch->file.xq);
2895 skb_queue_purge(&pch->file.rq);
2899 static void __exit ppp_cleanup(void)
2901 /* should never happen */
2902 if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count))
2903 pr_err("PPP: removing module but units remain!\n");
2904 unregister_chrdev(PPP_MAJOR, "ppp");
2905 device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0));
2906 class_destroy(ppp_class);
2907 unregister_pernet_device(&ppp_net_ops);
2911 * Units handling. Caller must protect concurrent access
2912 * by holding all_ppp_mutex
2915 static int __unit_alloc(struct idr *p, void *ptr, int n)
2920 if (!idr_pre_get(p, GFP_KERNEL)) {
2921 pr_err("PPP: No free memory for idr\n");
2925 err = idr_get_new_above(p, ptr, n, &unit);
2935 /* associate pointer with specified number */
2936 static int unit_set(struct idr *p, void *ptr, int n)
2940 unit = __unit_alloc(p, ptr, n);
2943 else if (unit != n) {
2944 idr_remove(p, unit);
2951 /* get new free unit number and associate pointer with it */
2952 static int unit_get(struct idr *p, void *ptr)
2954 return __unit_alloc(p, ptr, 0);
2957 /* put unit number back to a pool */
2958 static void unit_put(struct idr *p, int n)
2963 /* get pointer associated with the number */
2964 static void *unit_find(struct idr *p, int n)
2966 return idr_find(p, n);
2969 /* Module/initialization stuff */
2971 module_init(ppp_init);
2972 module_exit(ppp_cleanup);
2974 EXPORT_SYMBOL(ppp_register_net_channel);
2975 EXPORT_SYMBOL(ppp_register_channel);
2976 EXPORT_SYMBOL(ppp_unregister_channel);
2977 EXPORT_SYMBOL(ppp_channel_index);
2978 EXPORT_SYMBOL(ppp_unit_number);
2979 EXPORT_SYMBOL(ppp_dev_name);
2980 EXPORT_SYMBOL(ppp_input);
2981 EXPORT_SYMBOL(ppp_input_error);
2982 EXPORT_SYMBOL(ppp_output_wakeup);
2983 EXPORT_SYMBOL(ppp_register_compressor);
2984 EXPORT_SYMBOL(ppp_unregister_compressor);
2985 MODULE_LICENSE("GPL");
2986 MODULE_ALIAS_CHARDEV(PPP_MAJOR, 0);
2987 MODULE_ALIAS("devname:ppp");