| /* |
| * Generic PPP layer for Linux. |
| * |
| * Copyright 1999-2002 Paul Mackerras. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| * The generic PPP layer handles the PPP network interfaces, the |
| * /dev/ppp device, packet and VJ compression, and multilink. |
| * It talks to PPP `channels' via the interface defined in |
| * include/linux/ppp_channel.h. Channels provide the basic means for |
| * sending and receiving PPP frames on some kind of communications |
| * channel. |
| * |
| * Part of the code in this driver was inspired by the old async-only |
| * PPP driver, written by Michael Callahan and Al Longyear, and |
| * subsequently hacked by Paul Mackerras. |
| * |
| * ==FILEVERSION 20041108== |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/kmod.h> |
| #include <linux/init.h> |
| #include <linux/list.h> |
| #include <linux/netdevice.h> |
| #include <linux/poll.h> |
| #include <linux/ppp_defs.h> |
| #include <linux/filter.h> |
| #include <linux/if_ppp.h> |
| #include <linux/ppp_channel.h> |
| #include <linux/ppp-comp.h> |
| #include <linux/skbuff.h> |
| #include <linux/rtnetlink.h> |
| #include <linux/if_arp.h> |
| #include <linux/ip.h> |
| #include <linux/tcp.h> |
| #include <linux/smp_lock.h> |
| #include <linux/spinlock.h> |
| #include <linux/rwsem.h> |
| #include <linux/stddef.h> |
| #include <linux/device.h> |
| #include <linux/mutex.h> |
| #include <net/slhc_vj.h> |
| #include <asm/atomic.h> |
| |
| #define PPP_VERSION "2.4.2" |
| |
| /* |
| * Network protocols we support. |
| */ |
| #define NP_IP 0 /* Internet Protocol V4 */ |
| #define NP_IPV6 1 /* Internet Protocol V6 */ |
| #define NP_IPX 2 /* IPX protocol */ |
| #define NP_AT 3 /* Appletalk protocol */ |
| #define NP_MPLS_UC 4 /* MPLS unicast */ |
| #define NP_MPLS_MC 5 /* MPLS multicast */ |
| #define NUM_NP 6 /* Number of NPs. */ |
| |
| #define MPHDRLEN 6 /* multilink protocol header length */ |
| #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */ |
| #define MIN_FRAG_SIZE 64 |
| |
| /* |
| * An instance of /dev/ppp can be associated with either a ppp |
| * interface unit or a ppp channel. In both cases, file->private_data |
| * points to one of these. |
| */ |
| struct ppp_file { |
| enum { |
| INTERFACE=1, CHANNEL |
| } kind; |
| struct sk_buff_head xq; /* pppd transmit queue */ |
| struct sk_buff_head rq; /* receive queue for pppd */ |
| wait_queue_head_t rwait; /* for poll on reading /dev/ppp */ |
| atomic_t refcnt; /* # refs (incl /dev/ppp attached) */ |
| int hdrlen; /* space to leave for headers */ |
| int index; /* interface unit / channel number */ |
| int dead; /* unit/channel has been shut down */ |
| }; |
| |
| #define PF_TO_X(pf, X) container_of(pf, X, file) |
| |
| #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp) |
| #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel) |
| |
| /* |
| * Data structure describing one ppp unit. |
| * A ppp unit corresponds to a ppp network interface device |
| * and represents a multilink bundle. |
| * It can have 0 or more ppp channels connected to it. |
| */ |
| struct ppp { |
| struct ppp_file file; /* stuff for read/write/poll 0 */ |
| struct file *owner; /* file that owns this unit 48 */ |
| struct list_head channels; /* list of attached channels 4c */ |
| int n_channels; /* how many channels are attached 54 */ |
| spinlock_t rlock; /* lock for receive side 58 */ |
| spinlock_t wlock; /* lock for transmit side 5c */ |
| int mru; /* max receive unit 60 */ |
| unsigned int flags; /* control bits 64 */ |
| unsigned int xstate; /* transmit state bits 68 */ |
| unsigned int rstate; /* receive state bits 6c */ |
| int debug; /* debug flags 70 */ |
| struct slcompress *vj; /* state for VJ header compression */ |
| enum NPmode npmode[NUM_NP]; /* what to do with each net proto 78 */ |
| struct sk_buff *xmit_pending; /* a packet ready to go out 88 */ |
| struct compressor *xcomp; /* transmit packet compressor 8c */ |
| void *xc_state; /* its internal state 90 */ |
| struct compressor *rcomp; /* receive decompressor 94 */ |
| void *rc_state; /* its internal state 98 */ |
| unsigned long last_xmit; /* jiffies when last pkt sent 9c */ |
| unsigned long last_recv; /* jiffies when last pkt rcvd a0 */ |
| struct net_device *dev; /* network interface device a4 */ |
| #ifdef CONFIG_PPP_MULTILINK |
| int nxchan; /* next channel to send something on */ |
| u32 nxseq; /* next sequence number to send */ |
| int mrru; /* MP: max reconst. receive unit */ |
| u32 nextseq; /* MP: seq no of next packet */ |
| u32 minseq; /* MP: min of most recent seqnos */ |
| struct sk_buff_head mrq; /* MP: receive reconstruction queue */ |
| #endif /* CONFIG_PPP_MULTILINK */ |
| #ifdef CONFIG_PPP_FILTER |
| struct sock_filter *pass_filter; /* filter for packets to pass */ |
| struct sock_filter *active_filter;/* filter for pkts to reset idle */ |
| unsigned pass_len, active_len; |
| #endif /* CONFIG_PPP_FILTER */ |
| }; |
| |
| /* |
| * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC, |
| * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP, |
| * SC_MUST_COMP |
| * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR. |
| * Bits in xstate: SC_COMP_RUN |
| */ |
| #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \ |
| |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \ |
| |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP) |
| |
| /* |
| * Private data structure for each channel. |
| * This includes the data structure used for multilink. |
| */ |
| struct channel { |
| struct ppp_file file; /* stuff for read/write/poll */ |
| struct list_head list; /* link in all/new_channels list */ |
| struct ppp_channel *chan; /* public channel data structure */ |
| struct rw_semaphore chan_sem; /* protects `chan' during chan ioctl */ |
| spinlock_t downl; /* protects `chan', file.xq dequeue */ |
| struct ppp *ppp; /* ppp unit we're connected to */ |
| struct list_head clist; /* link in list of channels per unit */ |
| rwlock_t upl; /* protects `ppp' */ |
| #ifdef CONFIG_PPP_MULTILINK |
| u8 avail; /* flag used in multilink stuff */ |
| u8 had_frag; /* >= 1 fragments have been sent */ |
| u32 lastseq; /* MP: last sequence # received */ |
| #endif /* CONFIG_PPP_MULTILINK */ |
| }; |
| |
| /* |
| * SMP locking issues: |
| * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels |
| * list and the ppp.n_channels field, you need to take both locks |
| * before you modify them. |
| * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock -> |
| * channel.downl. |
| */ |
| |
| /* |
| * A cardmap represents a mapping from unsigned integers to pointers, |
| * and provides a fast "find lowest unused number" operation. |
| * It uses a broad (32-way) tree with a bitmap at each level. |
| * It is designed to be space-efficient for small numbers of entries |
| * and time-efficient for large numbers of entries. |
| */ |
| #define CARDMAP_ORDER 5 |
| #define CARDMAP_WIDTH (1U << CARDMAP_ORDER) |
| #define CARDMAP_MASK (CARDMAP_WIDTH - 1) |
| |
| struct cardmap { |
| int shift; |
| unsigned long inuse; |
| struct cardmap *parent; |
| void *ptr[CARDMAP_WIDTH]; |
| }; |
| static void *cardmap_get(struct cardmap *map, unsigned int nr); |
| static int cardmap_set(struct cardmap **map, unsigned int nr, void *ptr); |
| static unsigned int cardmap_find_first_free(struct cardmap *map); |
| static void cardmap_destroy(struct cardmap **map); |
| |
| /* |
| * all_ppp_mutex protects the all_ppp_units mapping. |
| * It also ensures that finding a ppp unit in the all_ppp_units map |
| * and updating its file.refcnt field is atomic. |
| */ |
| static DEFINE_MUTEX(all_ppp_mutex); |
| static struct cardmap *all_ppp_units; |
| static atomic_t ppp_unit_count = ATOMIC_INIT(0); |
| |
| /* |
| * all_channels_lock protects all_channels and last_channel_index, |
| * and the atomicity of find a channel and updating its file.refcnt |
| * field. |
| */ |
| static DEFINE_SPINLOCK(all_channels_lock); |
| static LIST_HEAD(all_channels); |
| static LIST_HEAD(new_channels); |
| static int last_channel_index; |
| static atomic_t channel_count = ATOMIC_INIT(0); |
| |
| /* Get the PPP protocol number from a skb */ |
| #define PPP_PROTO(skb) (((skb)->data[0] << 8) + (skb)->data[1]) |
| |
| /* We limit the length of ppp->file.rq to this (arbitrary) value */ |
| #define PPP_MAX_RQLEN 32 |
| |
| /* |
| * Maximum number of multilink fragments queued up. |
| * This has to be large enough to cope with the maximum latency of |
| * the slowest channel relative to the others. Strictly it should |
| * depend on the number of channels and their characteristics. |
| */ |
| #define PPP_MP_MAX_QLEN 128 |
| |
| /* Multilink header bits. */ |
| #define B 0x80 /* this fragment begins a packet */ |
| #define E 0x40 /* this fragment ends a packet */ |
| |
| /* Compare multilink sequence numbers (assumed to be 32 bits wide) */ |
| #define seq_before(a, b) ((s32)((a) - (b)) < 0) |
| #define seq_after(a, b) ((s32)((a) - (b)) > 0) |
| |
| /* Prototypes. */ |
| static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file, |
| unsigned int cmd, unsigned long arg); |
| static void ppp_xmit_process(struct ppp *ppp); |
| static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb); |
| static void ppp_push(struct ppp *ppp); |
| static void ppp_channel_push(struct channel *pch); |
| static void ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, |
| struct channel *pch); |
| static void ppp_receive_error(struct ppp *ppp); |
| static void ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb); |
| static struct sk_buff *ppp_decompress_frame(struct ppp *ppp, |
| struct sk_buff *skb); |
| #ifdef CONFIG_PPP_MULTILINK |
| static void ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, |
| struct channel *pch); |
| static void ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb); |
| static struct sk_buff *ppp_mp_reconstruct(struct ppp *ppp); |
| static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb); |
| #endif /* CONFIG_PPP_MULTILINK */ |
| static int ppp_set_compress(struct ppp *ppp, unsigned long arg); |
| static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound); |
| static void ppp_ccp_closed(struct ppp *ppp); |
| static struct compressor *find_compressor(int type); |
| static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st); |
| static struct ppp *ppp_create_interface(int unit, int *retp); |
| static void init_ppp_file(struct ppp_file *pf, int kind); |
| static void ppp_shutdown_interface(struct ppp *ppp); |
| static void ppp_destroy_interface(struct ppp *ppp); |
| static struct ppp *ppp_find_unit(int unit); |
| static struct channel *ppp_find_channel(int unit); |
| static int ppp_connect_channel(struct channel *pch, int unit); |
| static int ppp_disconnect_channel(struct channel *pch); |
| static void ppp_destroy_channel(struct channel *pch); |
| |
| static struct class *ppp_class; |
| |
| /* Translates a PPP protocol number to a NP index (NP == network protocol) */ |
| static inline int proto_to_npindex(int proto) |
| { |
| switch (proto) { |
| case PPP_IP: |
| return NP_IP; |
| case PPP_IPV6: |
| return NP_IPV6; |
| case PPP_IPX: |
| return NP_IPX; |
| case PPP_AT: |
| return NP_AT; |
| case PPP_MPLS_UC: |
| return NP_MPLS_UC; |
| case PPP_MPLS_MC: |
| return NP_MPLS_MC; |
| } |
| return -EINVAL; |
| } |
| |
| /* Translates an NP index into a PPP protocol number */ |
| static const int npindex_to_proto[NUM_NP] = { |
| PPP_IP, |
| PPP_IPV6, |
| PPP_IPX, |
| PPP_AT, |
| PPP_MPLS_UC, |
| PPP_MPLS_MC, |
| }; |
| |
| /* Translates an ethertype into an NP index */ |
| static inline int ethertype_to_npindex(int ethertype) |
| { |
| switch (ethertype) { |
| case ETH_P_IP: |
| return NP_IP; |
| case ETH_P_IPV6: |
| return NP_IPV6; |
| case ETH_P_IPX: |
| return NP_IPX; |
| case ETH_P_PPPTALK: |
| case ETH_P_ATALK: |
| return NP_AT; |
| case ETH_P_MPLS_UC: |
| return NP_MPLS_UC; |
| case ETH_P_MPLS_MC: |
| return NP_MPLS_MC; |
| } |
| return -1; |
| } |
| |
| /* Translates an NP index into an ethertype */ |
| static const int npindex_to_ethertype[NUM_NP] = { |
| ETH_P_IP, |
| ETH_P_IPV6, |
| ETH_P_IPX, |
| ETH_P_PPPTALK, |
| ETH_P_MPLS_UC, |
| ETH_P_MPLS_MC, |
| }; |
| |
| /* |
| * Locking shorthand. |
| */ |
| #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock) |
| #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock) |
| #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock) |
| #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock) |
| #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \ |
| ppp_recv_lock(ppp); } while (0) |
| #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \ |
| ppp_xmit_unlock(ppp); } while (0) |
| |
| /* |
| * /dev/ppp device routines. |
| * The /dev/ppp device is used by pppd to control the ppp unit. |
| * It supports the read, write, ioctl and poll functions. |
| * Open instances of /dev/ppp can be in one of three states: |
| * unattached, attached to a ppp unit, or attached to a ppp channel. |
| */ |
| static int ppp_open(struct inode *inode, struct file *file) |
| { |
| cycle_kernel_lock(); |
| /* |
| * This could (should?) be enforced by the permissions on /dev/ppp. |
| */ |
| if (!capable(CAP_NET_ADMIN)) |
| return -EPERM; |
| return 0; |
| } |
| |
| static int ppp_release(struct inode *unused, struct file *file) |
| { |
| struct ppp_file *pf = file->private_data; |
| struct ppp *ppp; |
| |
| if (pf) { |
| file->private_data = NULL; |
| if (pf->kind == INTERFACE) { |
| ppp = PF_TO_PPP(pf); |
| if (file == ppp->owner) |
| ppp_shutdown_interface(ppp); |
| } |
| if (atomic_dec_and_test(&pf->refcnt)) { |
| switch (pf->kind) { |
| case INTERFACE: |
| ppp_destroy_interface(PF_TO_PPP(pf)); |
| break; |
| case CHANNEL: |
| ppp_destroy_channel(PF_TO_CHANNEL(pf)); |
| break; |
| } |
| } |
| } |
| return 0; |
| } |
| |
| static ssize_t ppp_read(struct file *file, char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| struct ppp_file *pf = file->private_data; |
| DECLARE_WAITQUEUE(wait, current); |
| ssize_t ret; |
| struct sk_buff *skb = NULL; |
| |
| ret = count; |
| |
| if (!pf) |
| return -ENXIO; |
| add_wait_queue(&pf->rwait, &wait); |
| for (;;) { |
| set_current_state(TASK_INTERRUPTIBLE); |
| skb = skb_dequeue(&pf->rq); |
| if (skb) |
| break; |
| ret = 0; |
| if (pf->dead) |
| break; |
| if (pf->kind == INTERFACE) { |
| /* |
| * Return 0 (EOF) on an interface that has no |
| * channels connected, unless it is looping |
| * network traffic (demand mode). |
| */ |
| struct ppp *ppp = PF_TO_PPP(pf); |
| if (ppp->n_channels == 0 |
| && (ppp->flags & SC_LOOP_TRAFFIC) == 0) |
| break; |
| } |
| ret = -EAGAIN; |
| if (file->f_flags & O_NONBLOCK) |
| break; |
| ret = -ERESTARTSYS; |
| if (signal_pending(current)) |
| break; |
| schedule(); |
| } |
| set_current_state(TASK_RUNNING); |
| remove_wait_queue(&pf->rwait, &wait); |
| |
| if (!skb) |
| goto out; |
| |
| ret = -EOVERFLOW; |
| if (skb->len > count) |
| goto outf; |
| ret = -EFAULT; |
| if (copy_to_user(buf, skb->data, skb->len)) |
| goto outf; |
| ret = skb->len; |
| |
| outf: |
| kfree_skb(skb); |
| out: |
| return ret; |
| } |
| |
| static ssize_t ppp_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| struct ppp_file *pf = file->private_data; |
| struct sk_buff *skb; |
| ssize_t ret; |
| |
| if (!pf) |
| return -ENXIO; |
| ret = -ENOMEM; |
| skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL); |
| if (!skb) |
| goto out; |
| skb_reserve(skb, pf->hdrlen); |
| ret = -EFAULT; |
| if (copy_from_user(skb_put(skb, count), buf, count)) { |
| kfree_skb(skb); |
| goto out; |
| } |
| |
| skb_queue_tail(&pf->xq, skb); |
| |
| switch (pf->kind) { |
| case INTERFACE: |
| ppp_xmit_process(PF_TO_PPP(pf)); |
| break; |
| case CHANNEL: |
| ppp_channel_push(PF_TO_CHANNEL(pf)); |
| break; |
| } |
| |
| ret = count; |
| |
| out: |
| return ret; |
| } |
| |
| /* No kernel lock - fine */ |
| static unsigned int ppp_poll(struct file *file, poll_table *wait) |
| { |
| struct ppp_file *pf = file->private_data; |
| unsigned int mask; |
| |
| if (!pf) |
| return 0; |
| poll_wait(file, &pf->rwait, wait); |
| mask = POLLOUT | POLLWRNORM; |
| if (skb_peek(&pf->rq)) |
| mask |= POLLIN | POLLRDNORM; |
| if (pf->dead) |
| mask |= POLLHUP; |
| else if (pf->kind == INTERFACE) { |
| /* see comment in ppp_read */ |
| struct ppp *ppp = PF_TO_PPP(pf); |
| if (ppp->n_channels == 0 |
| && (ppp->flags & SC_LOOP_TRAFFIC) == 0) |
| mask |= POLLIN | POLLRDNORM; |
| } |
| |
| return mask; |
| } |
| |
| #ifdef CONFIG_PPP_FILTER |
| static int get_filter(void __user *arg, struct sock_filter **p) |
| { |
| struct sock_fprog uprog; |
| struct sock_filter *code = NULL; |
| int len, err; |
| |
| if (copy_from_user(&uprog, arg, sizeof(uprog))) |
| return -EFAULT; |
| |
| if (!uprog.len) { |
| *p = NULL; |
| return 0; |
| } |
| |
| len = uprog.len * sizeof(struct sock_filter); |
| code = kmalloc(len, GFP_KERNEL); |
| if (code == NULL) |
| return -ENOMEM; |
| |
| if (copy_from_user(code, uprog.filter, len)) { |
| kfree(code); |
| return -EFAULT; |
| } |
| |
| err = sk_chk_filter(code, uprog.len); |
| if (err) { |
| kfree(code); |
| return err; |
| } |
| |
| *p = code; |
| return uprog.len; |
| } |
| #endif /* CONFIG_PPP_FILTER */ |
| |
| static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
| { |
| struct ppp_file *pf = file->private_data; |
| struct ppp *ppp; |
| int err = -EFAULT, val, val2, i; |
| struct ppp_idle idle; |
| struct npioctl npi; |
| int unit, cflags; |
| struct slcompress *vj; |
| void __user *argp = (void __user *)arg; |
| int __user *p = argp; |
| |
| if (!pf) |
| return ppp_unattached_ioctl(pf, file, cmd, arg); |
| |
| if (cmd == PPPIOCDETACH) { |
| /* |
| * We have to be careful here... if the file descriptor |
| * has been dup'd, we could have another process in the |
| * middle of a poll using the same file *, so we had |
| * better not free the interface data structures - |
| * instead we fail the ioctl. Even in this case, we |
| * shut down the interface if we are the owner of it. |
| * Actually, we should get rid of PPPIOCDETACH, userland |
| * (i.e. pppd) could achieve the same effect by closing |
| * this fd and reopening /dev/ppp. |
| */ |
| err = -EINVAL; |
| lock_kernel(); |
| if (pf->kind == INTERFACE) { |
| ppp = PF_TO_PPP(pf); |
| if (file == ppp->owner) |
| ppp_shutdown_interface(ppp); |
| } |
| if (atomic_long_read(&file->f_count) <= 2) { |
| ppp_release(NULL, file); |
| err = 0; |
| } else |
| printk(KERN_DEBUG "PPPIOCDETACH file->f_count=%ld\n", |
| atomic_long_read(&file->f_count)); |
| unlock_kernel(); |
| return err; |
| } |
| |
| if (pf->kind == CHANNEL) { |
| struct channel *pch; |
| struct ppp_channel *chan; |
| |
| lock_kernel(); |
| pch = PF_TO_CHANNEL(pf); |
| |
| switch (cmd) { |
| case PPPIOCCONNECT: |
| if (get_user(unit, p)) |
| break; |
| err = ppp_connect_channel(pch, unit); |
| break; |
| |
| case PPPIOCDISCONN: |
| err = ppp_disconnect_channel(pch); |
| break; |
| |
| default: |
| down_read(&pch->chan_sem); |
| chan = pch->chan; |
| err = -ENOTTY; |
| if (chan && chan->ops->ioctl) |
| err = chan->ops->ioctl(chan, cmd, arg); |
| up_read(&pch->chan_sem); |
| } |
| unlock_kernel(); |
| return err; |
| } |
| |
| if (pf->kind != INTERFACE) { |
| /* can't happen */ |
| printk(KERN_ERR "PPP: not interface or channel??\n"); |
| return -EINVAL; |
| } |
| |
| lock_kernel(); |
| ppp = PF_TO_PPP(pf); |
| switch (cmd) { |
| case PPPIOCSMRU: |
| if (get_user(val, p)) |
| break; |
| ppp->mru = val; |
| err = 0; |
| break; |
| |
| case PPPIOCSFLAGS: |
| if (get_user(val, p)) |
| break; |
| ppp_lock(ppp); |
| cflags = ppp->flags & ~val; |
| ppp->flags = val & SC_FLAG_BITS; |
| ppp_unlock(ppp); |
| if (cflags & SC_CCP_OPEN) |
| ppp_ccp_closed(ppp); |
| err = 0; |
| break; |
| |
| case PPPIOCGFLAGS: |
| val = ppp->flags | ppp->xstate | ppp->rstate; |
| if (put_user(val, p)) |
| break; |
| err = 0; |
| break; |
| |
| case PPPIOCSCOMPRESS: |
| err = ppp_set_compress(ppp, arg); |
| break; |
| |
| case PPPIOCGUNIT: |
| if (put_user(ppp->file.index, p)) |
| break; |
| err = 0; |
| break; |
| |
| case PPPIOCSDEBUG: |
| if (get_user(val, p)) |
| break; |
| ppp->debug = val; |
| err = 0; |
| break; |
| |
| case PPPIOCGDEBUG: |
| if (put_user(ppp->debug, p)) |
| break; |
| err = 0; |
| break; |
| |
| case PPPIOCGIDLE: |
| idle.xmit_idle = (jiffies - ppp->last_xmit) / HZ; |
| idle.recv_idle = (jiffies - ppp->last_recv) / HZ; |
| if (copy_to_user(argp, &idle, sizeof(idle))) |
| break; |
| err = 0; |
| break; |
| |
| case PPPIOCSMAXCID: |
| if (get_user(val, p)) |
| break; |
| val2 = 15; |
| if ((val >> 16) != 0) { |
| val2 = val >> 16; |
| val &= 0xffff; |
| } |
| vj = slhc_init(val2+1, val+1); |
| if (!vj) { |
| printk(KERN_ERR "PPP: no memory (VJ compressor)\n"); |
| err = -ENOMEM; |
| break; |
| } |
| ppp_lock(ppp); |
| if (ppp->vj) |
| slhc_free(ppp->vj); |
| ppp->vj = vj; |
| ppp_unlock(ppp); |
| err = 0; |
| break; |
| |
| case PPPIOCGNPMODE: |
| case PPPIOCSNPMODE: |
| if (copy_from_user(&npi, argp, sizeof(npi))) |
| break; |
| err = proto_to_npindex(npi.protocol); |
| if (err < 0) |
| break; |
| i = err; |
| if (cmd == PPPIOCGNPMODE) { |
| err = -EFAULT; |
| npi.mode = ppp->npmode[i]; |
| if (copy_to_user(argp, &npi, sizeof(npi))) |
| break; |
| } else { |
| ppp->npmode[i] = npi.mode; |
| /* we may be able to transmit more packets now (??) */ |
| netif_wake_queue(ppp->dev); |
| } |
| err = 0; |
| break; |
| |
| #ifdef CONFIG_PPP_FILTER |
| case PPPIOCSPASS: |
| { |
| struct sock_filter *code; |
| err = get_filter(argp, &code); |
| if (err >= 0) { |
| ppp_lock(ppp); |
| kfree(ppp->pass_filter); |
| ppp->pass_filter = code; |
| ppp->pass_len = err; |
| ppp_unlock(ppp); |
| err = 0; |
| } |
| break; |
| } |
| case PPPIOCSACTIVE: |
| { |
| struct sock_filter *code; |
| err = get_filter(argp, &code); |
| if (err >= 0) { |
| ppp_lock(ppp); |
| kfree(ppp->active_filter); |
| ppp->active_filter = code; |
| ppp->active_len = err; |
| ppp_unlock(ppp); |
| err = 0; |
| } |
| break; |
| } |
| #endif /* CONFIG_PPP_FILTER */ |
| |
| #ifdef CONFIG_PPP_MULTILINK |
| case PPPIOCSMRRU: |
| if (get_user(val, p)) |
| break; |
| ppp_recv_lock(ppp); |
| ppp->mrru = val; |
| ppp_recv_unlock(ppp); |
| err = 0; |
| break; |
| #endif /* CONFIG_PPP_MULTILINK */ |
| |
| default: |
| err = -ENOTTY; |
| } |
| unlock_kernel(); |
| return err; |
| } |
| |
| static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file, |
| unsigned int cmd, unsigned long arg) |
| { |
| int unit, err = -EFAULT; |
| struct ppp *ppp; |
| struct channel *chan; |
| int __user *p = (int __user *)arg; |
| |
| lock_kernel(); |
| switch (cmd) { |
| case PPPIOCNEWUNIT: |
| /* Create a new ppp unit */ |
| if (get_user(unit, p)) |
| break; |
| ppp = ppp_create_interface(unit, &err); |
| if (!ppp) |
| break; |
| file->private_data = &ppp->file; |
| ppp->owner = file; |
| err = -EFAULT; |
| if (put_user(ppp->file.index, p)) |
| break; |
| err = 0; |
| break; |
| |
| case PPPIOCATTACH: |
| /* Attach to an existing ppp unit */ |
| if (get_user(unit, p)) |
| break; |
| mutex_lock(&all_ppp_mutex); |
| err = -ENXIO; |
| ppp = ppp_find_unit(unit); |
| if (ppp) { |
| atomic_inc(&ppp->file.refcnt); |
| file->private_data = &ppp->file; |
| err = 0; |
| } |
| mutex_unlock(&all_ppp_mutex); |
| break; |
| |
| case PPPIOCATTCHAN: |
| if (get_user(unit, p)) |
| break; |
| spin_lock_bh(&all_channels_lock); |
| err = -ENXIO; |
| chan = ppp_find_channel(unit); |
| if (chan) { |
| atomic_inc(&chan->file.refcnt); |
| file->private_data = &chan->file; |
| err = 0; |
| } |
| spin_unlock_bh(&all_channels_lock); |
| break; |
| |
| default: |
| err = -ENOTTY; |
| } |
| unlock_kernel(); |
| return err; |
| } |
| |
| static const struct file_operations ppp_device_fops = { |
| .owner = THIS_MODULE, |
| .read = ppp_read, |
| .write = ppp_write, |
| .poll = ppp_poll, |
| .unlocked_ioctl = ppp_ioctl, |
| .open = ppp_open, |
| .release = ppp_release |
| }; |
| |
| #define PPP_MAJOR 108 |
| |
| /* Called at boot time if ppp is compiled into the kernel, |
| or at module load time (from init_module) if compiled as a module. */ |
| static int __init ppp_init(void) |
| { |
| int err; |
| |
| printk(KERN_INFO "PPP generic driver version " PPP_VERSION "\n"); |
| err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops); |
| if (!err) { |
| ppp_class = class_create(THIS_MODULE, "ppp"); |
| if (IS_ERR(ppp_class)) { |
| err = PTR_ERR(ppp_class); |
| goto out_chrdev; |
| } |
| device_create_drvdata(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), |
| NULL, "ppp"); |
| } |
| |
| out: |
| if (err) |
| printk(KERN_ERR "failed to register PPP device (%d)\n", err); |
| return err; |
| |
| out_chrdev: |
| unregister_chrdev(PPP_MAJOR, "ppp"); |
| goto out; |
| } |
| |
| /* |
| * Network interface unit routines. |
| */ |
| static int |
| ppp_start_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| struct ppp *ppp = (struct ppp *) dev->priv; |
| int npi, proto; |
| unsigned char *pp; |
| |
| npi = ethertype_to_npindex(ntohs(skb->protocol)); |
| if (npi < 0) |
| goto outf; |
| |
| /* Drop, accept or reject the packet */ |
| switch (ppp->npmode[npi]) { |
| case NPMODE_PASS: |
| break; |
| case NPMODE_QUEUE: |
| /* it would be nice to have a way to tell the network |
| system to queue this one up for later. */ |
| goto outf; |
| case NPMODE_DROP: |
| case NPMODE_ERROR: |
| goto outf; |
| } |
| |
| /* Put the 2-byte PPP protocol number on the front, |
| making sure there is room for the address and control fields. */ |
| if (skb_cow_head(skb, PPP_HDRLEN)) |
| goto outf; |
| |
| pp = skb_push(skb, 2); |
| proto = npindex_to_proto[npi]; |
| pp[0] = proto >> 8; |
| pp[1] = proto; |
| |
| netif_stop_queue(dev); |
| skb_queue_tail(&ppp->file.xq, skb); |
| ppp_xmit_process(ppp); |
| return 0; |
| |
| outf: |
| kfree_skb(skb); |
| ++ppp->dev->stats.tx_dropped; |
| return 0; |
| } |
| |
| static int |
| ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) |
| { |
| struct ppp *ppp = dev->priv; |
| int err = -EFAULT; |
| void __user *addr = (void __user *) ifr->ifr_ifru.ifru_data; |
| struct ppp_stats stats; |
| struct ppp_comp_stats cstats; |
| char *vers; |
| |
| switch (cmd) { |
| case SIOCGPPPSTATS: |
| ppp_get_stats(ppp, &stats); |
| if (copy_to_user(addr, &stats, sizeof(stats))) |
| break; |
| err = 0; |
| break; |
| |
| case SIOCGPPPCSTATS: |
| memset(&cstats, 0, sizeof(cstats)); |
| if (ppp->xc_state) |
| ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c); |
| if (ppp->rc_state) |
| ppp->rcomp->decomp_stat(ppp->rc_state, &cstats.d); |
| if (copy_to_user(addr, &cstats, sizeof(cstats))) |
| break; |
| err = 0; |
| break; |
| |
| case SIOCGPPPVER: |
| vers = PPP_VERSION; |
| if (copy_to_user(addr, vers, strlen(vers) + 1)) |
| break; |
| err = 0; |
| break; |
| |
| default: |
| err = -EINVAL; |
| } |
| |
| return err; |
| } |
| |
| static void ppp_setup(struct net_device *dev) |
| { |
| dev->hard_header_len = PPP_HDRLEN; |
| dev->mtu = PPP_MTU; |
| dev->addr_len = 0; |
| dev->tx_queue_len = 3; |
| dev->type = ARPHRD_PPP; |
| dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; |
| } |
| |
| /* |
| * Transmit-side routines. |
| */ |
| |
| /* |
| * Called to do any work queued up on the transmit side |
| * that can now be done. |
| */ |
| static void |
| ppp_xmit_process(struct ppp *ppp) |
| { |
| struct sk_buff *skb; |
| |
| ppp_xmit_lock(ppp); |
| if (ppp->dev) { |
| ppp_push(ppp); |
| while (!ppp->xmit_pending |
| && (skb = skb_dequeue(&ppp->file.xq))) |
| ppp_send_frame(ppp, skb); |
| /* If there's no work left to do, tell the core net |
| code that we can accept some more. */ |
| if (!ppp->xmit_pending && !skb_peek(&ppp->file.xq)) |
| netif_wake_queue(ppp->dev); |
| } |
| ppp_xmit_unlock(ppp); |
| } |
| |
| static inline struct sk_buff * |
| pad_compress_skb(struct ppp *ppp, struct sk_buff *skb) |
| { |
| struct sk_buff *new_skb; |
| int len; |
| int new_skb_size = ppp->dev->mtu + |
| ppp->xcomp->comp_extra + ppp->dev->hard_header_len; |
| int compressor_skb_size = ppp->dev->mtu + |
| ppp->xcomp->comp_extra + PPP_HDRLEN; |
| new_skb = alloc_skb(new_skb_size, GFP_ATOMIC); |
| if (!new_skb) { |
| if (net_ratelimit()) |
| printk(KERN_ERR "PPP: no memory (comp pkt)\n"); |
| return NULL; |
| } |
| if (ppp->dev->hard_header_len > PPP_HDRLEN) |
| skb_reserve(new_skb, |
| ppp->dev->hard_header_len - PPP_HDRLEN); |
| |
| /* compressor still expects A/C bytes in hdr */ |
| len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2, |
| new_skb->data, skb->len + 2, |
| compressor_skb_size); |
| if (len > 0 && (ppp->flags & SC_CCP_UP)) { |
| kfree_skb(skb); |
| skb = new_skb; |
| skb_put(skb, len); |
| skb_pull(skb, 2); /* pull off A/C bytes */ |
| } else if (len == 0) { |
| /* didn't compress, or CCP not up yet */ |
| kfree_skb(new_skb); |
| new_skb = skb; |
| } else { |
| /* |
| * (len < 0) |
| * MPPE requires that we do not send unencrypted |
| * frames. The compressor will return -1 if we |
| * should drop the frame. We cannot simply test |
| * the compress_proto because MPPE and MPPC share |
| * the same number. |
| */ |
| if (net_ratelimit()) |
| printk(KERN_ERR "ppp: compressor dropped pkt\n"); |
| kfree_skb(skb); |
| kfree_skb(new_skb); |
| new_skb = NULL; |
| } |
| return new_skb; |
| } |
| |
| /* |
| * Compress and send a frame. |
| * The caller should have locked the xmit path, |
| * and xmit_pending should be 0. |
| */ |
| static void |
| ppp_send_frame(struct ppp *ppp, struct sk_buff *skb) |
| { |
| int proto = PPP_PROTO(skb); |
| struct sk_buff *new_skb; |
| int len; |
| unsigned char *cp; |
| |
| if (proto < 0x8000) { |
| #ifdef CONFIG_PPP_FILTER |
| /* check if we should pass this packet */ |
| /* the filter instructions are constructed assuming |
| a four-byte PPP header on each packet */ |
| *skb_push(skb, 2) = 1; |
| if (ppp->pass_filter |
| && sk_run_filter(skb, ppp->pass_filter, |
| ppp->pass_len) == 0) { |
| if (ppp->debug & 1) |
| printk(KERN_DEBUG "PPP: outbound frame not passed\n"); |
| kfree_skb(skb); |
| return; |
| } |
| /* if this packet passes the active filter, record the time */ |
| if (!(ppp->active_filter |
| && sk_run_filter(skb, ppp->active_filter, |
| ppp->active_len) == 0)) |
| ppp->last_xmit = jiffies; |
| skb_pull(skb, 2); |
| #else |
| /* for data packets, record the time */ |
| ppp->last_xmit = jiffies; |
| #endif /* CONFIG_PPP_FILTER */ |
| } |
| |
| ++ppp->dev->stats.tx_packets; |
| ppp->dev->stats.tx_bytes += skb->len - 2; |
| |
| switch (proto) { |
| case PPP_IP: |
| if (!ppp->vj || (ppp->flags & SC_COMP_TCP) == 0) |
| break; |
| /* try to do VJ TCP header compression */ |
| new_skb = alloc_skb(skb->len + ppp->dev->hard_header_len - 2, |
| GFP_ATOMIC); |
| if (!new_skb) { |
| printk(KERN_ERR "PPP: no memory (VJ comp pkt)\n"); |
| goto drop; |
| } |
| skb_reserve(new_skb, ppp->dev->hard_header_len - 2); |
| cp = skb->data + 2; |
| len = slhc_compress(ppp->vj, cp, skb->len - 2, |
| new_skb->data + 2, &cp, |
| !(ppp->flags & SC_NO_TCP_CCID)); |
| if (cp == skb->data + 2) { |
| /* didn't compress */ |
| kfree_skb(new_skb); |
| } else { |
| if (cp[0] & SL_TYPE_COMPRESSED_TCP) { |
| proto = PPP_VJC_COMP; |
| cp[0] &= ~SL_TYPE_COMPRESSED_TCP; |
| } else { |
| proto = PPP_VJC_UNCOMP; |
| cp[0] = skb->data[2]; |
| } |
| kfree_skb(skb); |
| skb = new_skb; |
| cp = skb_put(skb, len + 2); |
| cp[0] = 0; |
| cp[1] = proto; |
| } |
| break; |
| |
| case PPP_CCP: |
| /* peek at outbound CCP frames */ |
| ppp_ccp_peek(ppp, skb, 0); |
| break; |
| } |
| |
| /* try to do packet compression */ |
| if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state |
| && proto != PPP_LCP && proto != PPP_CCP) { |
| if (!(ppp->flags & SC_CCP_UP) && (ppp->flags & SC_MUST_COMP)) { |
| if (net_ratelimit()) |
| printk(KERN_ERR "ppp: compression required but down - pkt dropped.\n"); |
| goto drop; |
| } |
| skb = pad_compress_skb(ppp, skb); |
| if (!skb) |
| goto drop; |
| } |
| |
| /* |
| * If we are waiting for traffic (demand dialling), |
| * queue it up for pppd to receive. |
| */ |
| if (ppp->flags & SC_LOOP_TRAFFIC) { |
| if (ppp->file.rq.qlen > PPP_MAX_RQLEN) |
| goto drop; |
| skb_queue_tail(&ppp->file.rq, skb); |
| wake_up_interruptible(&ppp->file.rwait); |
| return; |
| } |
| |
| ppp->xmit_pending = skb; |
| ppp_push(ppp); |
| return; |
| |
| drop: |
| if (skb) |
| kfree_skb(skb); |
| ++ppp->dev->stats.tx_errors; |
| } |
| |
| /* |
| * Try to send the frame in xmit_pending. |
| * The caller should have the xmit path locked. |
| */ |
| static void |
| ppp_push(struct ppp *ppp) |
| { |
| struct list_head *list; |
| struct channel *pch; |
| struct sk_buff *skb = ppp->xmit_pending; |
| |
| if (!skb) |
| return; |
| |
| list = &ppp->channels; |
| if (list_empty(list)) { |
| /* nowhere to send the packet, just drop it */ |
| ppp->xmit_pending = NULL; |
| kfree_skb(skb); |
| return; |
| } |
| |
| if ((ppp->flags & SC_MULTILINK) == 0) { |
| /* not doing multilink: send it down the first channel */ |
| list = list->next; |
| pch = list_entry(list, struct channel, clist); |
| |
| spin_lock_bh(&pch->downl); |
| if (pch->chan) { |
| if (pch->chan->ops->start_xmit(pch->chan, skb)) |
| ppp->xmit_pending = NULL; |
| } else { |
| /* channel got unregistered */ |
| kfree_skb(skb); |
| ppp->xmit_pending = NULL; |
| } |
| spin_unlock_bh(&pch->downl); |
| return; |
| } |
| |
| #ifdef CONFIG_PPP_MULTILINK |
| /* Multilink: fragment the packet over as many links |
| as can take the packet at the moment. */ |
| if (!ppp_mp_explode(ppp, skb)) |
| return; |
| #endif /* CONFIG_PPP_MULTILINK */ |
| |
| ppp->xmit_pending = NULL; |
| kfree_skb(skb); |
| } |
| |
| #ifdef CONFIG_PPP_MULTILINK |
| /* |
| * Divide a packet to be transmitted into fragments and |
| * send them out the individual links. |
| */ |
| static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb) |
| { |
| int len, fragsize; |
| int i, bits, hdrlen, mtu; |
| int flen; |
| int navail, nfree; |
| int nbigger; |
| unsigned char *p, *q; |
| struct list_head *list; |
| struct channel *pch; |
| struct sk_buff *frag; |
| struct ppp_channel *chan; |
| |
| nfree = 0; /* # channels which have no packet already queued */ |
| navail = 0; /* total # of usable channels (not deregistered) */ |
| hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN; |
| i = 0; |
| list_for_each_entry(pch, &ppp->channels, clist) { |
| navail += pch->avail = (pch->chan != NULL); |
| if (pch->avail) { |
| if (skb_queue_empty(&pch->file.xq) || |
| !pch->had_frag) { |
| pch->avail = 2; |
| ++nfree; |
| } |
| if (!pch->had_frag && i < ppp->nxchan) |
| ppp->nxchan = i; |
| } |
| ++i; |
| } |
| |
| /* |
| * Don't start sending this packet unless at least half of |
| * the channels are free. This gives much better TCP |
| * performance if we have a lot of channels. |
| */ |
| if (nfree == 0 || nfree < navail / 2) |
| return 0; /* can't take now, leave it in xmit_pending */ |
| |
| /* Do protocol field compression (XXX this should be optional) */ |
| p = skb->data; |
| len = skb->len; |
| if (*p == 0) { |
| ++p; |
| --len; |
| } |
| |
| /* |
| * Decide on fragment size. |
| * We create a fragment for each free channel regardless of |
| * how small they are (i.e. even 0 length) in order to minimize |
| * the time that it will take to detect when a channel drops |
| * a fragment. |
| */ |
| fragsize = len; |
| if (nfree > 1) |
| fragsize = DIV_ROUND_UP(fragsize, nfree); |
| /* nbigger channels get fragsize bytes, the rest get fragsize-1, |
| except if nbigger==0, then they all get fragsize. */ |
| nbigger = len % nfree; |
| |
| /* skip to the channel after the one we last used |
| and start at that one */ |
| list = &ppp->channels; |
| for (i = 0; i < ppp->nxchan; ++i) { |
| list = list->next; |
| if (list == &ppp->channels) { |
| i = 0; |
| break; |
| } |
| } |
| |
| /* create a fragment for each channel */ |
| bits = B; |
| while (nfree > 0 || len > 0) { |
| list = list->next; |
| if (list == &ppp->channels) { |
| i = 0; |
| continue; |
| } |
| pch = list_entry(list, struct channel, clist); |
| ++i; |
| if (!pch->avail) |
| continue; |
| |
| /* |
| * Skip this channel if it has a fragment pending already and |
| * we haven't given a fragment to all of the free channels. |
| */ |
| if (pch->avail == 1) { |
| if (nfree > 0) |
| continue; |
| } else { |
| --nfree; |
| pch->avail = 1; |
| } |
| |
| /* check the channel's mtu and whether it is still attached. */ |
| spin_lock_bh(&pch->downl); |
| if (pch->chan == NULL) { |
| /* can't use this channel, it's being deregistered */ |
| spin_unlock_bh(&pch->downl); |
| pch->avail = 0; |
| if (--navail == 0) |
| break; |
| continue; |
| } |
| |
| /* |
| * Create a fragment for this channel of |
| * min(max(mtu+2-hdrlen, 4), fragsize, len) bytes. |
| * If mtu+2-hdrlen < 4, that is a ridiculously small |
| * MTU, so we use mtu = 2 + hdrlen. |
| */ |
| if (fragsize > len) |
| fragsize = len; |
| flen = fragsize; |
| mtu = pch->chan->mtu + 2 - hdrlen; |
| if (mtu < 4) |
| mtu = 4; |
| if (flen > mtu) |
| flen = mtu; |
| if (flen == len && nfree == 0) |
| bits |= E; |
| frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC); |
| if (!frag) |
| goto noskb; |
| q = skb_put(frag, flen + hdrlen); |
| |
| /* make the MP header */ |
| q[0] = PPP_MP >> 8; |
| q[1] = PPP_MP; |
| if (ppp->flags & SC_MP_XSHORTSEQ) { |
| q[2] = bits + ((ppp->nxseq >> 8) & 0xf); |
| q[3] = ppp->nxseq; |
| } else { |
| q[2] = bits; |
| q[3] = ppp->nxseq >> 16; |
| q[4] = ppp->nxseq >> 8; |
| q[5] = ppp->nxseq; |
| } |
| |
| /* |
| * Copy the data in. |
| * Unfortunately there is a bug in older versions of |
| * the Linux PPP multilink reconstruction code where it |
| * drops 0-length fragments. Therefore we make sure the |
| * fragment has at least one byte of data. Any bytes |
| * we add in this situation will end up as padding on the |
| * end of the reconstructed packet. |
| */ |
| if (flen == 0) |
| *skb_put(frag, 1) = 0; |
| else |
| memcpy(q + hdrlen, p, flen); |
| |
| /* try to send it down the channel */ |
| chan = pch->chan; |
| if (!skb_queue_empty(&pch->file.xq) || |
| !chan->ops->start_xmit(chan, frag)) |
| skb_queue_tail(&pch->file.xq, frag); |
| pch->had_frag = 1; |
| p += flen; |
| len -= flen; |
| ++ppp->nxseq; |
| bits = 0; |
| spin_unlock_bh(&pch->downl); |
| |
| if (--nbigger == 0 && fragsize > 0) |
| --fragsize; |
| } |
| ppp->nxchan = i; |
| |
| return 1; |
| |
| noskb: |
| spin_unlock_bh(&pch->downl); |
| if (ppp->debug & 1) |
| printk(KERN_ERR "PPP: no memory (fragment)\n"); |
| ++ppp->dev->stats.tx_errors; |
| ++ppp->nxseq; |
| return 1; /* abandon the frame */ |
| } |
| #endif /* CONFIG_PPP_MULTILINK */ |
| |
| /* |
| * Try to send data out on a channel. |
| */ |
| static void |
| ppp_channel_push(struct channel *pch) |
| { |
| struct sk_buff *skb; |
| struct ppp *ppp; |
| |
| spin_lock_bh(&pch->downl); |
| if (pch->chan) { |
| while (!skb_queue_empty(&pch->file.xq)) { |
| skb = skb_dequeue(&pch->file.xq); |
| if (!pch->chan->ops->start_xmit(pch->chan, skb)) { |
| /* put the packet back and try again later */ |
| skb_queue_head(&pch->file.xq, skb); |
| break; |
| } |
| } |
| } else { |
| /* channel got deregistered */ |
| skb_queue_purge(&pch->file.xq); |
| } |
| spin_unlock_bh(&pch->downl); |
| /* see if there is anything from the attached unit to be sent */ |
| if (skb_queue_empty(&pch->file.xq)) { |
| read_lock_bh(&pch->upl); |
| ppp = pch->ppp; |
| if (ppp) |
| ppp_xmit_process(ppp); |
| read_unlock_bh(&pch->upl); |
| } |
| } |
| |
| /* |
| * Receive-side routines. |
| */ |
| |
| /* misuse a few fields of the skb for MP reconstruction */ |
| #define sequence priority |
| #define BEbits cb[0] |
| |
| static inline void |
| ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) |
| { |
| ppp_recv_lock(ppp); |
| /* ppp->dev == 0 means interface is closing down */ |
| if (ppp->dev) |
| ppp_receive_frame(ppp, skb, pch); |
| else |
| kfree_skb(skb); |
| ppp_recv_unlock(ppp); |
| } |
| |
| void |
| ppp_input(struct ppp_channel *chan, struct sk_buff *skb) |
| { |
| struct channel *pch = chan->ppp; |
| int proto; |
| |
| if (!pch || skb->len == 0) { |
| kfree_skb(skb); |
| return; |
| } |
| |
| proto = PPP_PROTO(skb); |
| read_lock_bh(&pch->upl); |
| if (!pch->ppp || proto >= 0xc000 || proto == PPP_CCPFRAG) { |
| /* put it on the channel queue */ |
| skb_queue_tail(&pch->file.rq, skb); |
| /* drop old frames if queue too long */ |
| while (pch->file.rq.qlen > PPP_MAX_RQLEN |
| && (skb = skb_dequeue(&pch->file.rq))) |
| kfree_skb(skb); |
| wake_up_interruptible(&pch->file.rwait); |
| } else { |
| ppp_do_recv(pch->ppp, skb, pch); |
| } |
| read_unlock_bh(&pch->upl); |
| } |
| |
| /* Put a 0-length skb in the receive queue as an error indication */ |
| void |
| ppp_input_error(struct ppp_channel *chan, int code) |
| { |
| struct channel *pch = chan->ppp; |
| struct sk_buff *skb; |
| |
| if (!pch) |
| return; |
| |
| read_lock_bh(&pch->upl); |
| if (pch->ppp) { |
| skb = alloc_skb(0, GFP_ATOMIC); |
| if (skb) { |
| skb->len = 0; /* probably unnecessary */ |
| skb->cb[0] = code; |
| ppp_do_recv(pch->ppp, skb, pch); |
| } |
| } |
| read_unlock_bh(&pch->upl); |
| } |
| |
| /* |
| * We come in here to process a received frame. |
| * The receive side of the ppp unit is locked. |
| */ |
| static void |
| ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) |
| { |
| if (pskb_may_pull(skb, 2)) { |
| #ifdef CONFIG_PPP_MULTILINK |
| /* XXX do channel-level decompression here */ |
| if (PPP_PROTO(skb) == PPP_MP) |
| ppp_receive_mp_frame(ppp, skb, pch); |
| else |
| #endif /* CONFIG_PPP_MULTILINK */ |
| ppp_receive_nonmp_frame(ppp, skb); |
| return; |
| } |
| |
| if (skb->len > 0) |
| /* note: a 0-length skb is used as an error indication */ |
| ++ppp->dev->stats.rx_length_errors; |
| |
| kfree_skb(skb); |
| ppp_receive_error(ppp); |
| } |
| |
| static void |
| ppp_receive_error(struct ppp *ppp) |
| { |
| ++ppp->dev->stats.rx_errors; |
| if (ppp->vj) |
| slhc_toss(ppp->vj); |
| } |
| |
| static void |
| ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb) |
| { |
| struct sk_buff *ns; |
| int proto, len, npi; |
| |
| /* |
| * Decompress the frame, if compressed. |
| * Note that some decompressors need to see uncompressed frames |
| * that come in as well as compressed frames. |
| */ |
| if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN) |
| && (ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0) |
| skb = ppp_decompress_frame(ppp, skb); |
| |
| if (ppp->flags & SC_MUST_COMP && ppp->rstate & SC_DC_FERROR) |
| goto err; |
| |
| proto = PPP_PROTO(skb); |
| switch (proto) { |
| case PPP_VJC_COMP: |
| /* decompress VJ compressed packets */ |
| if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP)) |
| goto err; |
| |
| if (skb_tailroom(skb) < 124 || skb_cloned(skb)) { |
| /* copy to a new sk_buff with more tailroom */ |
| ns = dev_alloc_skb(skb->len + 128); |
| if (!ns) { |
| printk(KERN_ERR"PPP: no memory (VJ decomp)\n"); |
| goto err; |
| } |
| skb_reserve(ns, 2); |
| skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len); |
| kfree_skb(skb); |
| skb = ns; |
| } |
| else |
| skb->ip_summed = CHECKSUM_NONE; |
| |
| len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2); |
| if (len <= 0) { |
| printk(KERN_DEBUG "PPP: VJ decompression error\n"); |
| goto err; |
| } |
| len += 2; |
| if (len > skb->len) |
| skb_put(skb, len - skb->len); |
| else if (len < skb->len) |
| skb_trim(skb, len); |
| proto = PPP_IP; |
| break; |
| |
| case PPP_VJC_UNCOMP: |
| if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP)) |
| goto err; |
| |
| /* Until we fix the decompressor need to make sure |
| * data portion is linear. |
| */ |
| if (!pskb_may_pull(skb, skb->len)) |
| goto err; |
| |
| if (slhc_remember(ppp->vj, skb->data + 2, skb->len - 2) <= 0) { |
| printk(KERN_ERR "PPP: VJ uncompressed error\n"); |
| goto err; |
| } |
| proto = PPP_IP; |
| break; |
| |
| case PPP_CCP: |
| ppp_ccp_peek(ppp, skb, 1); |
| break; |
| } |
| |
| ++ppp->dev->stats.rx_packets; |
| ppp->dev->stats.rx_bytes += skb->len - 2; |
| |
| npi = proto_to_npindex(proto); |
| if (npi < 0) { |
| /* control or unknown frame - pass it to pppd */ |
| skb_queue_tail(&ppp->file.rq, skb); |
| /* limit queue length by dropping old frames */ |
| while (ppp->file.rq.qlen > PPP_MAX_RQLEN |
| && (skb = skb_dequeue(&ppp->file.rq))) |
| kfree_skb(skb); |
| /* wake up any process polling or blocking on read */ |
| wake_up_interruptible(&ppp->file.rwait); |
| |
| } else { |
| /* network protocol frame - give it to the kernel */ |
| |
| #ifdef CONFIG_PPP_FILTER |
| /* check if the packet passes the pass and active filters */ |
| /* the filter instructions are constructed assuming |
| a four-byte PPP header on each packet */ |
| if (ppp->pass_filter || ppp->active_filter) { |
| if (skb_cloned(skb) && |
| pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) |
| goto err; |
| |
| *skb_push(skb, 2) = 0; |
| if (ppp->pass_filter |
| && sk_run_filter(skb, ppp->pass_filter, |
| ppp->pass_len) == 0) { |
| if (ppp->debug & 1) |
| printk(KERN_DEBUG "PPP: inbound frame " |
| "not passed\n"); |
| kfree_skb(skb); |
| return; |
| } |
| if (!(ppp->active_filter |
| && sk_run_filter(skb, ppp->active_filter, |
| ppp->active_len) == 0)) |
| ppp->last_recv = jiffies; |
| __skb_pull(skb, 2); |
| } else |
| #endif /* CONFIG_PPP_FILTER */ |
| ppp->last_recv = jiffies; |
| |
| if ((ppp->dev->flags & IFF_UP) == 0 |
| || ppp->npmode[npi] != NPMODE_PASS) { |
| kfree_skb(skb); |
| } else { |
| /* chop off protocol */ |
| skb_pull_rcsum(skb, 2); |
| skb->dev = ppp->dev; |
| skb->protocol = htons(npindex_to_ethertype[npi]); |
| skb_reset_mac_header(skb); |
| netif_rx(skb); |
| ppp->dev->last_rx = jiffies; |
| } |
| } |
| return; |
| |
| err: |
| kfree_skb(skb); |
| ppp_receive_error(ppp); |
| } |
| |
| static struct sk_buff * |
| ppp_decompress_frame(struct ppp *ppp, struct sk_buff *skb) |
| { |
| int proto = PPP_PROTO(skb); |
| struct sk_buff *ns; |
| int len; |
| |
| /* Until we fix all the decompressor's need to make sure |
| * data portion is linear. |
| */ |
| if (!pskb_may_pull(skb, skb->len)) |
| goto err; |
| |
| if (proto == PPP_COMP) { |
| int obuff_size; |
| |
| switch(ppp->rcomp->compress_proto) { |
| case CI_MPPE: |
| obuff_size = ppp->mru + PPP_HDRLEN + 1; |
| break; |
| default: |
| obuff_size = ppp->mru + PPP_HDRLEN; |
| break; |
| } |
| |
| ns = dev_alloc_skb(obuff_size); |
| if (!ns) { |
| printk(KERN_ERR "ppp_decompress_frame: no memory\n"); |
| goto err; |
| } |
| /* the decompressor still expects the A/C bytes in the hdr */ |
| len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2, |
| skb->len + 2, ns->data, obuff_size); |
| if (len < 0) { |
| /* Pass the compressed frame to pppd as an |
| error indication. */ |
| if (len == DECOMP_FATALERROR) |
| ppp->rstate |= SC_DC_FERROR; |
| kfree_skb(ns); |
| goto err; |
| } |
| |
| kfree_skb(skb); |
| skb = ns; |
| skb_put(skb, len); |
| skb_pull(skb, 2); /* pull off the A/C bytes */ |
| |
| } else { |
| /* Uncompressed frame - pass to decompressor so it |
| can update its dictionary if necessary. */ |
| if (ppp->rcomp->incomp) |
| ppp->rcomp->incomp(ppp->rc_state, skb->data - 2, |
| skb->len + 2); |
| } |
| |
| return skb; |
| |
| err: |
| ppp->rstate |= SC_DC_ERROR; |
| ppp_receive_error(ppp); |
| return skb; |
| } |
| |
| #ifdef CONFIG_PPP_MULTILINK |
| /* |
| * Receive a multilink frame. |
| * We put it on the reconstruction queue and then pull off |
| * as many completed frames as we can. |
| */ |
| static void |
| ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) |
| { |
| u32 mask, seq; |
| struct channel *ch; |
| int mphdrlen = (ppp->flags & SC_MP_SHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN; |
| |
| if (!pskb_may_pull(skb, mphdrlen + 1) || ppp->mrru == 0) |
| goto err; /* no good, throw it away */ |
| |
| /* Decode sequence number and begin/end bits */ |
| if (ppp->flags & SC_MP_SHORTSEQ) { |
| seq = ((skb->data[2] & 0x0f) << 8) | skb->data[3]; |
| mask = 0xfff; |
| } else { |
| seq = (skb->data[3] << 16) | (skb->data[4] << 8)| skb->data[5]; |
| mask = 0xffffff; |
| } |
| skb->BEbits = skb->data[2]; |
| skb_pull(skb, mphdrlen); /* pull off PPP and MP headers */ |
| |
| /* |
| * Do protocol ID decompression on the first fragment of each packet. |
| */ |
| if ((skb->BEbits & B) && (skb->data[0] & 1)) |
| *skb_push(skb, 1) = 0; |
| |
| /* |
| * Expand sequence number to 32 bits, making it as close |
| * as possible to ppp->minseq. |
| */ |
| seq |= ppp->minseq & ~mask; |
| if ((int)(ppp->minseq - seq) > (int)(mask >> 1)) |
| seq += mask + 1; |
| else if ((int)(seq - ppp->minseq) > (int)(mask >> 1)) |
| seq -= mask + 1; /* should never happen */ |
| skb->sequence = seq; |
| pch->lastseq = seq; |
| |
| /* |
| * If this packet comes before the next one we were expecting, |
| * drop it. |
| */ |
| if (seq_before(seq, ppp->nextseq)) { |
| kfree_skb(skb); |
| ++ppp->dev->stats.rx_dropped; |
| ppp_receive_error(ppp); |
| return; |
| } |
| |
| /* |
| * Reevaluate minseq, the minimum over all channels of the |
| * last sequence number received on each channel. Because of |
| * the increasing sequence number rule, we know that any fragment |
| * before `minseq' which hasn't arrived is never going to arrive. |
| * The list of channels can't change because we have the receive |
| * side of the ppp unit locked. |
| */ |
| list_for_each_entry(ch, &ppp->channels, clist) { |
| if (seq_before(ch->lastseq, seq)) |
| seq = ch->lastseq; |
| } |
| if (seq_before(ppp->minseq, seq)) |
| ppp->minseq = seq; |
| |
| /* Put the fragment on the reconstruction queue */ |
| ppp_mp_insert(ppp, skb); |
| |
| /* If the queue is getting long, don't wait any longer for packets |
| before the start of the queue. */ |
| if (skb_queue_len(&ppp->mrq) >= PPP_MP_MAX_QLEN |
| && seq_before(ppp->minseq, ppp->mrq.next->sequence)) |
| ppp->minseq = ppp->mrq.next->sequence; |
| |
| /* Pull completed packets off the queue and receive them. */ |
| while ((skb = ppp_mp_reconstruct(ppp))) |
| ppp_receive_nonmp_frame(ppp, skb); |
| |
| return; |
| |
| err: |
| kfree_skb(skb); |
| ppp_receive_error(ppp); |
| } |
| |
| /* |
| * Insert a fragment on the MP reconstruction queue. |
| * The queue is ordered by increasing sequence number. |
| */ |
| static void |
| ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb) |
| { |
| struct sk_buff *p; |
| struct sk_buff_head *list = &ppp->mrq; |
| u32 seq = skb->sequence; |
| |
| /* N.B. we don't need to lock the list lock because we have the |
| ppp unit receive-side lock. */ |
| for (p = list->next; p != (struct sk_buff *)list; p = p->next) |
| if (seq_before(seq, p->sequence)) |
| break; |
| __skb_queue_before(list, p, skb); |
| } |
| |
| /* |
| * Reconstruct a packet from the MP fragment queue. |
| * We go through increasing sequence numbers until we find a |
| * complete packet, or we get to the sequence number for a fragment |
| * which hasn't arrived but might still do so. |
| */ |
| static struct sk_buff * |
| ppp_mp_reconstruct(struct ppp *ppp) |
| { |
| u32 seq = ppp->nextseq; |
| u32 minseq = ppp->minseq; |
| struct sk_buff_head *list = &ppp->mrq; |
| struct sk_buff *p, *next; |
| struct sk_buff *head, *tail; |
| struct sk_buff *skb = NULL; |
| int lost = 0, len = 0; |
| |
| if (ppp->mrru == 0) /* do nothing until mrru is set */ |
| return NULL; |
| head = list->next; |
| tail = NULL; |
| for (p = head; p != (struct sk_buff *) list; p = next) { |
| next = p->next; |
| if (seq_before(p->sequence, seq)) { |
| /* this can't happen, anyway ignore the skb */ |
| printk(KERN_ERR "ppp_mp_reconstruct bad seq %u < %u\n", |
| p->sequence, seq); |
| head = next; |
| continue; |
| } |
| if (p->sequence != seq) { |
| /* Fragment `seq' is missing. If it is after |
| minseq, it might arrive later, so stop here. */ |
| if (seq_after(seq, minseq)) |
| break; |
| /* Fragment `seq' is lost, keep going. */ |
| lost = 1; |
| seq = seq_before(minseq, p->sequence)? |
| minseq + 1: p->sequence; |
| next = p; |
| continue; |
| } |
| |
| /* |
| * At this point we know that all the fragments from |
| * ppp->nextseq to seq are either present or lost. |
| * Also, there are no complete packets in the queue |
| * that have no missing fragments and end before this |
| * fragment. |
| */ |
| |
| /* B bit set indicates this fragment starts a packet */ |
| if (p->BEbits & B) { |
| head = p; |
| lost = 0; |
| len = 0; |
| } |
| |
| len += p->len; |
| |
| /* Got a complete packet yet? */ |
| if (lost == 0 && (p->BEbits & E) && (head->BEbits & B)) { |
| if (len > ppp->mrru + 2) { |
| ++ppp->dev->stats.rx_length_errors; |
| printk(KERN_DEBUG "PPP: reconstructed packet" |
| " is too long (%d)\n", len); |
| } else if (p == head) { |
| /* fragment is complete packet - reuse skb */ |
| tail = p; |
| skb = skb_get(p); |
| break; |
| } else if ((skb = dev_alloc_skb(len)) == NULL) { |
| ++ppp->dev->stats.rx_missed_errors; |
| printk(KERN_DEBUG "PPP: no memory for " |
| "reconstructed packet"); |
| } else { |
| tail = p; |
| break; |
| } |
| ppp->nextseq = seq + 1; |
| } |
| |
| /* |
| * If this is the ending fragment of a packet, |
| * and we haven't found a complete valid packet yet, |
| * we can discard up to and including this fragment. |
| */ |
| if (p->BEbits & E) |
| head = next; |
| |
| ++seq; |
| } |
| |
| /* If we have a complete packet, copy it all into one skb. */ |
| if (tail != NULL) { |
| /* If we have discarded any fragments, |
| signal a receive error. */ |
| if (head->sequence != ppp->nextseq) { |
| if (ppp->debug & 1) |
| printk(KERN_DEBUG " missed pkts %u..%u\n", |
| ppp->nextseq, head->sequence-1); |
| ++ppp->dev->stats.rx_dropped; |
| ppp_receive_error(ppp); |
| } |
| |
| if (head != tail) |
| /* copy to a single skb */ |
| for (p = head; p != tail->next; p = p->next) |
| skb_copy_bits(p, 0, skb_put(skb, p->len), p->len); |
| ppp->nextseq = tail->sequence + 1; |
| head = tail->next; |
| } |
| |
| /* Discard all the skbuffs that we have copied the data out of |
| or that we can't use. */ |
| while ((p = list->next) != head) { |
| __skb_unlink(p, list); |
| kfree_skb(p); |
| } |
| |
| return skb; |
| } |
| #endif /* CONFIG_PPP_MULTILINK */ |
| |
| /* |
| * Channel interface. |
| */ |
| |
| /* |
| * Create a new, unattached ppp channel. |
| */ |
| int |
| ppp_register_channel(struct ppp_channel *chan) |
| { |
| struct channel *pch; |
| |
| pch = kzalloc(sizeof(struct channel), GFP_KERNEL); |
| if (!pch) |
| return -ENOMEM; |
| pch->ppp = NULL; |
| pch->chan = chan; |
| chan->ppp = pch; |
| init_ppp_file(&pch->file, CHANNEL); |
| pch->file.hdrlen = chan->hdrlen; |
| #ifdef CONFIG_PPP_MULTILINK |
| pch->lastseq = -1; |
| #endif /* CONFIG_PPP_MULTILINK */ |
| init_rwsem(&pch->chan_sem); |
| spin_lock_init(&pch->downl); |
| rwlock_init(&pch->upl); |
| spin_lock_bh(&all_channels_lock); |
| pch->file.index = ++last_channel_index; |
| list_add(&pch->list, &new_channels); |
| atomic_inc(&channel_count); |
| spin_unlock_bh(&all_channels_lock); |
| return 0; |
| } |
| |
| /* |
| * Return the index of a channel. |
| */ |
| int ppp_channel_index(struct ppp_channel *chan) |
| { |
| struct channel *pch = chan->ppp; |
| |
| if (pch) |
| return pch->file.index; |
| return -1; |
| } |
| |
| /* |
| * Return the PPP unit number to which a channel is connected. |
| */ |
| int ppp_unit_number(struct ppp_channel *chan) |
| { |
| struct channel *pch = chan->ppp; |
| int unit = -1; |
| |
| if (pch) { |
| read_lock_bh(&pch->upl); |
| if (pch->ppp) |
| unit = pch->ppp->file.index; |
| read_unlock_bh(&pch->upl); |
| } |
| return unit; |
| } |
| |
| /* |
| * Disconnect a channel from the generic layer. |
| * This must be called in process context. |
| */ |
| void |
| ppp_unregister_channel(struct ppp_channel *chan) |
| { |
| struct channel *pch = chan->ppp; |
| |
| if (!pch) |
| return; /* should never happen */ |
| chan->ppp = NULL; |
| |
| /* |
| * This ensures that we have returned from any calls into the |
| * the channel's start_xmit or ioctl routine before we proceed. |
| */ |
| down_write(&pch->chan_sem); |
| spin_lock_bh(&pch->downl); |
| pch->chan = NULL; |
| spin_unlock_bh(&pch->downl); |
| up_write(&pch->chan_sem); |
| ppp_disconnect_channel(pch); |
| spin_lock_bh(&all_channels_lock); |
| list_del(&pch->list); |
| spin_unlock_bh(&all_channels_lock); |
| pch->file.dead = 1; |
| wake_up_interruptible(&pch->file.rwait); |
| if (atomic_dec_and_test(&pch->file.refcnt)) |
| ppp_destroy_channel(pch); |
| } |
| |
| /* |
| * Callback from a channel when it can accept more to transmit. |
| * This should be called at BH/softirq level, not interrupt level. |
| */ |
| void |
| ppp_output_wakeup(struct ppp_channel *chan) |
| { |
| struct channel *pch = chan->ppp; |
| |
| if (!pch) |
| return; |
| ppp_channel_push(pch); |
| } |
| |
| /* |
| * Compression control. |
| */ |
| |
| /* Process the PPPIOCSCOMPRESS ioctl. */ |
| static int |
| ppp_set_compress(struct ppp *ppp, unsigned long arg) |
| { |
| int err; |
| struct compressor *cp, *ocomp; |
| struct ppp_option_data data; |
| void *state, *ostate; |
| unsigned char ccp_option[CCP_MAX_OPTION_LENGTH]; |
| |
| err = -EFAULT; |
| if (copy_from_user(&data, (void __user *) arg, sizeof(data)) |
| || (data.length <= CCP_MAX_OPTION_LENGTH |
| && copy_from_user(ccp_option, (void __user *) data.ptr, data.length))) |
| goto out; |
| err = -EINVAL; |
| if (data.length > CCP_MAX_OPTION_LENGTH |
| || ccp_option[1] < 2 || ccp_option[1] > data.length) |
| goto out; |
| |
| cp = find_compressor(ccp_option[0]); |
| #ifdef CONFIG_KMOD |
| if (!cp) { |
| request_module("ppp-compress-%d", ccp_option[0]); |
| cp = find_compressor(ccp_option[0]); |
| } |
| #endif /* CONFIG_KMOD */ |
| if (!cp) |
| goto out; |
| |
| err = -ENOBUFS; |
| if (data.transmit) { |
| state = cp->comp_alloc(ccp_option, data.length); |
| if (state) { |
| ppp_xmit_lock(ppp); |
| ppp->xstate &= ~SC_COMP_RUN; |
| ocomp = ppp->xcomp; |
| ostate = ppp->xc_state; |
| ppp->xcomp = cp; |
| ppp->xc_state = state; |
| ppp_xmit_unlock(ppp); |
| if (ostate) { |
| ocomp->comp_free(ostate); |
| module_put(ocomp->owner); |
| } |
| err = 0; |
| } else |
| module_put(cp->owner); |
| |
| } else { |
| state = cp->decomp_alloc(ccp_option, data.length); |
| if (state) { |
| ppp_recv_lock(ppp); |
| ppp->rstate &= ~SC_DECOMP_RUN; |
| ocomp = ppp->rcomp; |
| ostate = ppp->rc_state; |
| ppp->rcomp = cp; |
| ppp->rc_state = state; |
| ppp_recv_unlock(ppp); |
| if (ostate) { |
| ocomp->decomp_free(ostate); |
| module_put(ocomp->owner); |
| } |
| err = 0; |
| } else |
| module_put(cp->owner); |
| } |
| |
| out: |
| return err; |
| } |
| |
| /* |
| * Look at a CCP packet and update our state accordingly. |
| * We assume the caller has the xmit or recv path locked. |
| */ |
| static void |
| ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound) |
| { |
| unsigned char *dp; |
| int len; |
| |
| if (!pskb_may_pull(skb, CCP_HDRLEN + 2)) |
| return; /* no header */ |
| dp = skb->data + 2; |
| |
| switch (CCP_CODE(dp)) { |
| case CCP_CONFREQ: |
| |
| /* A ConfReq starts negotiation of compression |
| * in one direction of transmission, |
| * and hence brings it down...but which way? |
| * |
| * Remember: |
| * A ConfReq indicates what the sender would like to receive |
| */ |
| if(inbound) |
| /* He is proposing what I should send */ |
| ppp->xstate &= ~SC_COMP_RUN; |
| else |
| /* I am proposing to what he should send */ |
| ppp->rstate &= ~SC_DECOMP_RUN; |
| |
| break; |
| |
| case CCP_TERMREQ: |
| case CCP_TERMACK: |
| /* |
| * CCP is going down, both directions of transmission |
| */ |
| ppp->rstate &= ~SC_DECOMP_RUN; |
| ppp->xstate &= ~SC_COMP_RUN; |
| break; |
| |
| case CCP_CONFACK: |
| if ((ppp->flags & (SC_CCP_OPEN | SC_CCP_UP)) != SC_CCP_OPEN) |
| break; |
| len = CCP_LENGTH(dp); |
| if (!pskb_may_pull(skb, len + 2)) |
| return; /* too short */ |
| dp += CCP_HDRLEN; |
| len -= CCP_HDRLEN; |
| if (len < CCP_OPT_MINLEN || len < CCP_OPT_LENGTH(dp)) |
| break; |
| if (inbound) { |
| /* we will start receiving compressed packets */ |
| if (!ppp->rc_state) |
| break; |
| if (ppp->rcomp->decomp_init(ppp->rc_state, dp, len, |
| ppp->file.index, 0, ppp->mru, ppp->debug)) { |
| ppp->rstate |= SC_DECOMP_RUN; |
| ppp->rstate &= ~(SC_DC_ERROR | SC_DC_FERROR); |
| } |
| } else { |
| /* we will soon start sending compressed packets */ |
| if (!ppp->xc_state) |
| break; |
| if (ppp->xcomp->comp_init(ppp->xc_state, dp, len, |
| ppp->file.index, 0, ppp->debug)) |
| ppp->xstate |= SC_COMP_RUN; |
| } |
| break; |
| |
| case CCP_RESETACK: |
| /* reset the [de]compressor */ |
| if ((ppp->flags & SC_CCP_UP) == 0) |
| break; |
| if (inbound) { |
| if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN)) { |
| ppp->rcomp->decomp_reset(ppp->rc_state); |
| ppp->rstate &= ~SC_DC_ERROR; |
| } |
| } else { |
| if (ppp->xc_state && (ppp->xstate & SC_COMP_RUN)) |
| ppp->xcomp->comp_reset(ppp->xc_state); |
| } |
| break; |
| } |
| } |
| |
| /* Free up compression resources. */ |
| static void |
| ppp_ccp_closed(struct ppp *ppp) |
| { |
| void *xstate, *rstate; |
| struct compressor *xcomp, *rcomp; |
| |
| ppp_lock(ppp); |
| ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP); |
| ppp->xstate = 0; |
| xcomp = ppp->xcomp; |
| xstate = ppp->xc_state; |
| ppp->xc_state = NULL; |
| ppp->rstate = 0; |
| rcomp = ppp->rcomp; |
| rstate = ppp->rc_state; |
| ppp->rc_state = NULL; |
| ppp_unlock(ppp); |
| |
| if (xstate) { |
| xcomp->comp_free(xstate); |
| module_put(xcomp->owner); |
| } |
| if (rstate) { |
| rcomp->decomp_free(rstate); |
| module_put(rcomp->owner); |
| } |
| } |
| |
| /* List of compressors. */ |
| static LIST_HEAD(compressor_list); |
| static DEFINE_SPINLOCK(compressor_list_lock); |
| |
| struct compressor_entry { |
| struct list_head list; |
| struct compressor *comp; |
| }; |
| |
| static struct compressor_entry * |
| find_comp_entry(int proto) |
| { |
| struct compressor_entry *ce; |
| |
| list_for_each_entry(ce, &compressor_list, list) { |
| if (ce->comp->compress_proto == proto) |
| return ce; |
| } |
| return NULL; |
| } |
| |
| /* Register a compressor */ |
| int |
| ppp_register_compressor(struct compressor *cp) |
| { |
| struct compressor_entry *ce; |
| int ret; |
| spin_lock(&compressor_list_lock); |
| ret = -EEXIST; |
| if (find_comp_entry(cp->compress_proto)) |
| goto out; |
| ret = -ENOMEM; |
| ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC); |
| if (!ce) |
| goto out; |
| ret = 0; |
| ce->comp = cp; |
| list_add(&ce->list, &compressor_list); |
| out: |
| spin_unlock(&compressor_list_lock); |
| return ret; |
| } |
| |
| /* Unregister a compressor */ |
| void |
| ppp_unregister_compressor(struct compressor *cp) |
| { |
| struct compressor_entry *ce; |
| |
| spin_lock(&compressor_list_lock); |
| ce = find_comp_entry(cp->compress_proto); |
| if (ce && ce->comp == cp) { |
| list_del(&ce->list); |
| kfree(ce); |
| } |
| spin_unlock(&compressor_list_lock); |
| } |
| |
| /* Find a compressor. */ |
| static struct compressor * |
| find_compressor(int type) |
| { |
| struct compressor_entry *ce; |
| struct compressor *cp = NULL; |
| |
| spin_lock(&compressor_list_lock); |
| ce = find_comp_entry(type); |
| if (ce) { |
| cp = ce->comp; |
| if (!try_module_get(cp->owner)) |
| cp = NULL; |
| } |
| spin_unlock(&compressor_list_lock); |
| return cp; |
| } |
| |
| /* |
| * Miscelleneous stuff. |
| */ |
| |
| static void |
| ppp_get_stats(struct ppp *ppp, struct ppp_stats *st) |
| { |
| struct slcompress *vj = ppp->vj; |
| |
| memset(st, 0, sizeof(*st)); |
| st->p.ppp_ipackets = ppp->dev->stats.rx_packets; |
| st->p.ppp_ierrors = ppp->dev->stats.rx_errors; |
| st->p.ppp_ibytes = ppp->dev->stats.rx_bytes; |
| st->p.ppp_opackets = ppp->dev->stats.tx_packets; |
| st->p.ppp_oerrors = ppp->dev->stats.tx_errors; |
| st->p.ppp_obytes = ppp->dev->stats.tx_bytes; |
| if (!vj) |
| return; |
| st->vj.vjs_packets = vj->sls_o_compressed + vj->sls_o_uncompressed; |
| st->vj.vjs_compressed = vj->sls_o_compressed; |
| st->vj.vjs_searches = vj->sls_o_searches; |
| st->vj.vjs_misses = vj->sls_o_misses; |
| st->vj.vjs_errorin = vj->sls_i_error; |
| st->vj.vjs_tossed = vj->sls_i_tossed; |
| st->vj.vjs_uncompressedin = vj->sls_i_uncompressed; |
| st->vj.vjs_compressedin = vj->sls_i_compressed; |
| } |
| |
| /* |
| * Stuff for handling the lists of ppp units and channels |
| * and for initialization. |
| */ |
| |
| /* |
| * Create a new ppp interface unit. Fails if it can't allocate memory |
| * or if there is already a unit with the requested number. |
| * unit == -1 means allocate a new number. |
| */ |
| static struct ppp * |
| ppp_create_interface(int unit, int *retp) |
| { |
| struct ppp *ppp; |
| struct net_device *dev = NULL; |
| int ret = -ENOMEM; |
| int i; |
| |
| ppp = kzalloc(sizeof(struct ppp), GFP_KERNEL); |
| if (!ppp) |
| goto out; |
| dev = alloc_netdev(0, "", ppp_setup); |
| if (!dev) |
| goto out1; |
| |
| ppp->mru = PPP_MRU; |
| init_ppp_file(&ppp->file, INTERFACE); |
| ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */ |
| for (i = 0; i < NUM_NP; ++i) |
| ppp->npmode[i] = NPMODE_PASS; |
| INIT_LIST_HEAD(&ppp->channels); |
| spin_lock_init(&ppp->rlock); |
| spin_lock_init(&ppp->wlock); |
| #ifdef CONFIG_PPP_MULTILINK |
| ppp->minseq = -1; |
| skb_queue_head_init(&ppp->mrq); |
| #endif /* CONFIG_PPP_MULTILINK */ |
| ppp->dev = dev; |
| dev->priv = ppp; |
| |
| dev->hard_start_xmit = ppp_start_xmit; |
| dev->do_ioctl = ppp_net_ioctl; |
| |
| ret = -EEXIST; |
| mutex_lock(&all_ppp_mutex); |
| if (unit < 0) |
| unit = cardmap_find_first_free(all_ppp_units); |
| else if (cardmap_get(all_ppp_units, unit) != NULL) |
| goto out2; /* unit already exists */ |
| |
| /* Initialize the new ppp unit */ |
| ppp->file.index = unit; |
| sprintf(dev->name, "ppp%d", unit); |
| |
| ret = register_netdev(dev); |
| if (ret != 0) { |
| printk(KERN_ERR "PPP: couldn't register device %s (%d)\n", |
| dev->name, ret); |
| goto out2; |
| } |
| |
| atomic_inc(&ppp_unit_count); |
| ret = cardmap_set(&all_ppp_units, unit, ppp); |
| if (ret != 0) |
| goto out3; |
| |
| mutex_unlock(&all_ppp_mutex); |
| *retp = 0; |
| return ppp; |
| |
| out3: |
| atomic_dec(&ppp_unit_count); |
| unregister_netdev(dev); |
| out2: |
| mutex_unlock(&all_ppp_mutex); |
| free_netdev(dev); |
| out1: |
| kfree(ppp); |
| out: |
| *retp = ret; |
| return NULL; |
| } |
| |
| /* |
| * Initialize a ppp_file structure. |
| */ |
| static void |
| init_ppp_file(struct ppp_file *pf, int kind) |
| { |
| pf->kind = kind; |
| skb_queue_head_init(&pf->xq); |
| skb_queue_head_init(&pf->rq); |
| atomic_set(&pf->refcnt, 1); |
| init_waitqueue_head(&pf->rwait); |
| } |
| |
| /* |
| * Take down a ppp interface unit - called when the owning file |
| * (the one that created the unit) is closed or detached. |
| */ |
| static void ppp_shutdown_interface(struct ppp *ppp) |
| { |
| struct net_device *dev; |
| |
| mutex_lock(&all_ppp_mutex); |
| ppp_lock(ppp); |
| dev = ppp->dev; |
| ppp->dev = NULL; |
| ppp_unlock(ppp); |
| /* This will call dev_close() for us. */ |
| if (dev) { |
| unregister_netdev(dev); |
| free_netdev(dev); |
| } |
| cardmap_set(&all_ppp_units, ppp->file.index, NULL); |
| ppp->file.dead = 1; |
| ppp->owner = NULL; |
| wake_up_interruptible(&ppp->file.rwait); |
| mutex_unlock(&all_ppp_mutex); |
| } |
| |
| /* |
| * Free the memory used by a ppp unit. This is only called once |
| * there are no channels connected to the unit and no file structs |
| * that reference the unit. |
| */ |
| static void ppp_destroy_interface(struct ppp *ppp) |
| { |
| atomic_dec(&ppp_unit_count); |
| |
| if (!ppp->file.dead || ppp->n_channels) { |
| /* "can't happen" */ |
| printk(KERN_ERR "ppp: destroying ppp struct %p but dead=%d " |
| "n_channels=%d !\n", ppp, ppp->file.dead, |
| ppp->n_channels); |
| return; |
| } |
| |
| ppp_ccp_closed(ppp); |
| if (ppp->vj) { |
| slhc_free(ppp->vj); |
| ppp->vj = NULL; |
| } |
| skb_queue_purge(&ppp->file.xq); |
| skb_queue_purge(&ppp->file.rq); |
| #ifdef CONFIG_PPP_MULTILINK |
| skb_queue_purge(&ppp->mrq); |
| #endif /* CONFIG_PPP_MULTILINK */ |
| #ifdef CONFIG_PPP_FILTER |
| kfree(ppp->pass_filter); |
| ppp->pass_filter = NULL; |
| kfree(ppp->active_filter); |
| ppp->active_filter = NULL; |
| #endif /* CONFIG_PPP_FILTER */ |
| |
| if (ppp->xmit_pending) |
| kfree_skb(ppp->xmit_pending); |
| |
| kfree(ppp); |
| } |
| |
| /* |
| * Locate an existing ppp unit. |
| * The caller should have locked the all_ppp_mutex. |
| */ |
| static struct ppp * |
| ppp_find_unit(int unit) |
| { |
| return cardmap_get(all_ppp_units, unit); |
| } |
| |
| /* |
| * Locate an existing ppp channel. |
| * The caller should have locked the all_channels_lock. |
| * First we look in the new_channels list, then in the |
| * all_channels list. If found in the new_channels list, |
| * we move it to the all_channels list. This is for speed |
| * when we have a lot of channels in use. |
| */ |
| static struct channel * |
| ppp_find_channel(int unit) |
| { |
| struct channel *pch; |
| |
| list_for_each_entry(pch, &new_channels, list) { |
| if (pch->file.index == unit) { |
| list_move(&pch->list, &all_channels); |
| return pch; |
| } |
| } |
| list_for_each_entry(pch, &all_channels, list) { |
| if (pch->file.index == unit) |
| return pch; |
| } |
| return NULL; |
| } |
| |
| /* |
| * Connect a PPP channel to a PPP interface unit. |
| */ |
| static int |
| ppp_connect_channel(struct channel *pch, int unit) |
| { |
| struct ppp *ppp; |
| int ret = -ENXIO; |
| int hdrlen; |
| |
| mutex_lock(&all_ppp_mutex); |
| ppp = ppp_find_unit(unit); |
| if (!ppp) |
| goto out; |
| write_lock_bh(&pch->upl); |
| ret = -EINVAL; |
| if (pch->ppp) |
| goto outl; |
| |
| ppp_lock(ppp); |
| if (pch->file.hdrlen > ppp->file.hdrlen) |
| ppp->file.hdrlen = pch->file.hdrlen; |
| hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */ |
| if (ppp->dev && hdrlen > ppp->dev->hard_header_len) |
| ppp->dev->hard_header_len = hdrlen; |
| list_add_tail(&pch->clist, &ppp->channels); |
| ++ppp->n_channels; |
| pch->ppp = ppp; |
| atomic_inc(&ppp->file.refcnt); |
| ppp_unlock(ppp); |
| ret = 0; |
| |
| outl: |
| write_unlock_bh(&pch->upl); |
| out: |
| mutex_unlock(&all_ppp_mutex); |
| return ret; |
| } |
| |
| /* |
| * Disconnect a channel from its ppp unit. |
| */ |
| static int |
| ppp_disconnect_channel(struct channel *pch) |
| { |
| struct ppp *ppp; |
| int err = -EINVAL; |
| |
| write_lock_bh(&pch->upl); |
| ppp = pch->ppp; |
| pch->ppp = NULL; |
| write_unlock_bh(&pch->upl); |
| if (ppp) { |
| /* remove it from the ppp unit's list */ |
| ppp_lock(ppp); |
| list_del(&pch->clist); |
| if (--ppp->n_channels == 0) |
| wake_up_interruptible(&ppp->file.rwait); |
| ppp_unlock(ppp); |
| if (atomic_dec_and_test(&ppp->file.refcnt)) |
| ppp_destroy_interface(ppp); |
| err = 0; |
| } |
| return err; |
| } |
| |
| /* |
| * Free up the resources used by a ppp channel. |
| */ |
| static void ppp_destroy_channel(struct channel *pch) |
| { |
| atomic_dec(&channel_count); |
| |
| if (!pch->file.dead) { |
| /* "can't happen" */ |
| printk(KERN_ERR "ppp: destroying undead channel %p !\n", |
| pch); |
| return; |
| } |
| skb_queue_purge(&pch->file.xq); |
| skb_queue_purge(&pch->file.rq); |
| kfree(pch); |
| } |
| |
| static void __exit ppp_cleanup(void) |
| { |
| /* should never happen */ |
| if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count)) |
| printk(KERN_ERR "PPP: removing module but units remain!\n"); |
| cardmap_destroy(&all_ppp_units); |
| unregister_chrdev(PPP_MAJOR, "ppp"); |
| device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0)); |
| class_destroy(ppp_class); |
| } |
| |
| /* |
| * Cardmap implementation. |
| */ |
| static void *cardmap_get(struct cardmap *map, unsigned int nr) |
| { |
| struct cardmap *p; |
| int i; |
| |
| for (p = map; p != NULL; ) { |
| if ((i = nr >> p->shift) >= CARDMAP_WIDTH) |
| return NULL; |
| if (p->shift == 0) |
| return p->ptr[i]; |
| nr &= ~(CARDMAP_MASK << p->shift); |
| p = p->ptr[i]; |
| } |
| return NULL; |
| } |
| |
| static int cardmap_set(struct cardmap **pmap, unsigned int nr, void *ptr) |
| { |
| struct cardmap *p; |
| int i; |
| |
| p = *pmap; |
| if (p == NULL || (nr >> p->shift) >= CARDMAP_WIDTH) { |
| do { |
| /* need a new top level */ |
| struct cardmap *np = kzalloc(sizeof(*np), GFP_KERNEL); |
| if (!np) |
| goto enomem; |
| np->ptr[0] = p; |
| if (p != NULL) { |
| np->shift = p->shift + CARDMAP_ORDER; |
| p->parent = np; |
| } else |
| np->shift = 0; |
| p = np; |
| } while ((nr >> p->shift) >= CARDMAP_WIDTH); |
| *pmap = p; |
| } |
| while (p->shift > 0) { |
| i = (nr >> p->shift) & CARDMAP_MASK; |
| if (p->ptr[i] == NULL) { |
| struct cardmap *np = kzalloc(sizeof(*np), GFP_KERNEL); |
| if (!np) |
| goto enomem; |
| np->shift = p->shift - CARDMAP_ORDER; |
| np->parent = p; |
| p->ptr[i] = np; |
| } |
| if (ptr == NULL) |
| clear_bit(i, &p->inuse); |
| p = p->ptr[i]; |
| } |
| i = nr & CARDMAP_MASK; |
| p->ptr[i] = ptr; |
| if (ptr != NULL) |
| set_bit(i, &p->inuse); |
| else |
| clear_bit(i, &p->inuse); |
| return 0; |
| enomem: |
| return -ENOMEM; |
| } |
| |
| static unsigned int cardmap_find_first_free(struct cardmap *map) |
| { |
| struct cardmap *p; |
| unsigned int nr = 0; |
| int i; |
| |
| if ((p = map) == NULL) |
| return 0; |
| for (;;) { |
| i = find_first_zero_bit(&p->inuse, CARDMAP_WIDTH); |
| if (i >= CARDMAP_WIDTH) { |
| if (p->parent == NULL) |
| return CARDMAP_WIDTH << p->shift; |
| p = p->parent; |
| i = (nr >> p->shift) & CARDMAP_MASK; |
| set_bit(i, &p->inuse); |
| continue; |
| } |
| nr = (nr & (~CARDMAP_MASK << p->shift)) | (i << p->shift); |
| if (p->shift == 0 || p->ptr[i] == NULL) |
| return nr; |
| p = p->ptr[i]; |
| } |
| } |
| |
| static void cardmap_destroy(struct cardmap **pmap) |
| { |
| struct cardmap *p, *np; |
| int i; |
| |
| for (p = *pmap; p != NULL; p = np) { |
| if (p->shift != 0) { |
| for (i = 0; i < CARDMAP_WIDTH; ++i) |
| if (p->ptr[i] != NULL) |
| break; |
| if (i < CARDMAP_WIDTH) { |
| np = p->ptr[i]; |
| p->ptr[i] = NULL; |
| continue; |
| } |
| } |
| np = p->parent; |
| kfree(p); |
| } |
| *pmap = NULL; |
| } |
| |
| /* Module/initialization stuff */ |
| |
| module_init(ppp_init); |
| module_exit(ppp_cleanup); |
| |
| EXPORT_SYMBOL(ppp_register_channel); |
| EXPORT_SYMBOL(ppp_unregister_channel); |
| EXPORT_SYMBOL(ppp_channel_index); |
| EXPORT_SYMBOL(ppp_unit_number); |
| EXPORT_SYMBOL(ppp_input); |
| EXPORT_SYMBOL(ppp_input_error); |
| EXPORT_SYMBOL(ppp_output_wakeup); |
| EXPORT_SYMBOL(ppp_register_compressor); |
| EXPORT_SYMBOL(ppp_unregister_compressor); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS_CHARDEV_MAJOR(PPP_MAJOR); |
| MODULE_ALIAS("/dev/ppp"); |