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/* PPP for Linux * * Michael Callahan <callahan@maths.ox.ac.uk> * Al Longyear <longyear@netcom.com> * * Dynamic PPP devices by Jim Freeman <jfree@caldera.com>. * ppp_tty_receive ``noisy-raise-bug'' fixed by Ove Ewerlid <ewerlid@syscon.uu.se> * * ==FILEVERSION 970703== * * NOTE TO MAINTAINERS: * If you modify this file at all, please set the number above to the * date of the modification as YYMMDD (year month day). * ppp.c is shipped with a PPP distribution as well as with the kernel; * if everyone increases the FILEVERSION number above, then scripts * can do the right thing when deciding whether to install a new ppp.c * file. Don't change the format of that line otherwise, so the * installation script can recognize it. */ /* Sources: slip.c RFC1331: The Point-to-Point Protocol (PPP) for the Transmission of Multi-protocol Datagrams over Point-to-Point Links RFC1332: IPCP ppp-2.0 Flags for this module (any combination is acceptable for testing.): OPTIMIZE_FLAG_TIME - Number of jiffies to force sending of leading flag character. This is normally set to ((HZ * 3) / 2). This is 1.5 seconds. If zero then the leading flag is always sent. CHECK_CHARACTERS - Enable the checking on all received characters for 8 data bits, no parity. This adds a small amount of processing for each received character. */ #define OPTIMIZE_FLAG_TIME ((HZ * 3)/2) #define CHECK_CHARACTERS 1 #define PPP_COMPRESS 1 #ifndef PPP_MAX_DEV #define PPP_MAX_DEV 256 #endif /* $Id: ppp.c,v 1.1.1.1 2001-09-10 07:43:53 simons Exp $ * Added dynamic allocation of channels to eliminate * compiled-in limits on the number of channels. * * Dynamic channel allocation code Copyright 1995 Caldera, Inc., * released under the GNU General Public License Version 2. */ #include <linux/autoconf.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/types.h> #include <linux/fcntl.h> #include <linux/interrupt.h> #include <linux/ptrace.h> #include <linux/ioport.h> #include <linux/in.h> #include <linux/malloc.h> #include <linux/tty.h> #include <linux/errno.h> #include <linux/sched.h> /* to get the struct task_struct */ #include <linux/string.h> /* used in new tty drivers */ #include <linux/signal.h> /* used in new tty drivers */ #include <asm/system.h> #include <asm/bitops.h> #include <asm/segment.h> #include <linux/if.h> #include <linux/if_ether.h> #include <linux/netdevice.h> #include <linux/skbuff.h> #include <linux/inet.h> #include <linux/ioctl.h> typedef struct sk_buff sk_buff; #define skb_data(skb) ((__u8 *) (skb)->data) #include <linux/ip.h> #include <linux/tcp.h> #include <linux/if_arp.h> #include <net/slhc_vj.h> #define fcstab ppp_crc16_table /* Name of the table in the kernel */ #include <linux/ppp_defs.h> #include <linux/socket.h> #include <linux/if_ppp.h> #include <linux/if_pppvar.h> #undef PACKETPTR #define PACKETPTR 1 #include <linux/ppp-comp.h> #undef PACKETPTR #define bsd_decompress (*ppp->sc_rcomp->decompress) #define bsd_compress (*ppp->sc_xcomp->compress) #ifndef PPP_IPX #define PPP_IPX 0x2b /* IPX protocol over PPP */ #endif #ifndef PPP_LQR #define PPP_LQR 0xc025 /* Link Quality Reporting Protocol */ #endif static int ppp_register_compressor (struct compressor *cp); static void ppp_unregister_compressor (struct compressor *cp); /* * Local functions */ static struct compressor *find_compressor (int type); static void ppp_init_ctrl_blk (register struct ppp *); static void ppp_kick_tty (struct ppp *, struct ppp_buffer *bfr); static int ppp_doframe (struct ppp *); static struct ppp *ppp_alloc (void); static struct ppp *ppp_find (int pid_value); static void ppp_print_buffer (const __u8 *, const __u8 *, int); extern inline void ppp_stuff_char (struct ppp *ppp, register struct ppp_buffer *buf, register __u8 chr); extern inline int lock_buffer (register struct ppp_buffer *buf); static int rcv_proto_ip (struct ppp *, __u16, __u8 *, int); static int rcv_proto_ipx (struct ppp *, __u16, __u8 *, int); static int rcv_proto_vjc_comp (struct ppp *, __u16, __u8 *, int); static int rcv_proto_vjc_uncomp (struct ppp *, __u16, __u8 *, int); static int rcv_proto_unknown (struct ppp *, __u16, __u8 *, int); static int rcv_proto_lqr (struct ppp *, __u16, __u8 *, int); static void ppp_doframe_lower (struct ppp *, __u8 *, int); static int ppp_doframe (struct ppp *); extern int ppp_bsd_compressor_init(void); static void ppp_proto_ccp (struct ppp *ppp, __u8 *dp, int len, int rcvd); static int rcv_proto_ccp (struct ppp *, __u16, __u8 *, int); #define ins_char(pbuf,c) (buf_base(pbuf) [(pbuf)->count++] = (__u8)(c)) #ifndef OPTIMIZE_FLAG_TIME #define OPTIMIZE_FLAG_TIME 0 #endif #ifndef PPP_MAX_DEV #define PPP_MAX_DEV 256 #endif /* * Parameters which may be changed via insmod. */ static int flag_time = OPTIMIZE_FLAG_TIME; static int max_dev = PPP_MAX_DEV; /* * The "main" procedure to the ppp device */ int ppp_init (struct device *); /* * Network device driver callback routines */ static int ppp_dev_open (struct device *); static int ppp_dev_ioctl (struct device *dev, struct ifreq *ifr, int cmd); static int ppp_dev_close (struct device *); static int ppp_dev_xmit (sk_buff *, struct device *); static struct enet_statistics *ppp_dev_stats (struct device *); static int ppp_dev_header (sk_buff *, struct device *, __u16, void *, void *, unsigned int); static int ppp_dev_rebuild (void *eth, struct device *dev, unsigned long raddr, struct sk_buff *skb); /* * TTY callbacks */ static int ppp_tty_read (struct tty_struct *, struct file *, __u8 *, unsigned int); static int ppp_tty_write (struct tty_struct *, struct file *, const __u8 *, unsigned int); static int ppp_tty_ioctl (struct tty_struct *, struct file *, unsigned int, unsigned long); static int ppp_tty_select (struct tty_struct *tty, struct inode *inode, struct file *filp, int sel_type, select_table * wait); static int ppp_tty_open (struct tty_struct *); static void ppp_tty_close (struct tty_struct *); static int ppp_tty_room (struct tty_struct *tty); static void ppp_tty_receive (struct tty_struct *tty, const __u8 * cp, char *fp, int count); static void ppp_tty_wakeup (struct tty_struct *tty); #define CHECK_PPP(a) if (!ppp->inuse) { printk (ppp_warning, __LINE__); return a;} #define CHECK_PPP_VOID() if (!ppp->inuse) { printk (ppp_warning, __LINE__); return;} #define in_xmap(ppp,c) (ppp->xmit_async_map[(c) >> 5] & (1 << ((c) & 0x1f))) #define in_rmap(ppp,c) ((((unsigned int) (__u8) (c)) < 0x20) && \ ppp->recv_async_map & (1 << (c))) #define bset(p,b) ((p)[(b) >> 5] |= (1 << ((b) & 0x1f))) #define tty2ppp(tty) ((struct ppp *) (tty->disc_data)) #define dev2ppp(dev) ((struct ppp *) (dev->priv)) #define ppp2tty(ppp) ((struct tty_struct *) ppp->tty) #define ppp2dev(ppp) ((struct device *) ppp->dev) struct ppp_hdr { __u8 address; __u8 control; __u8 protocol[2]; }; #define PPP_HARD_HDR_LEN (sizeof (struct ppp_hdr)) typedef struct ppp_ctrl { struct ppp_ctrl *next; /* Next structure in the list */ char name [8]; /* Name of the device */ struct ppp ppp; /* PPP control table */ struct device dev; /* Device information table */ } ppp_ctrl_t; static ppp_ctrl_t *ppp_list = NULL; #define ctl2ppp(ctl) (struct ppp *) &ctl->ppp #define ctl2dev(ctl) (struct device *) &ctl->dev #undef PPP_NRUNIT /* Buffer types */ #define BUFFER_TYPE_DEV_RD 0 /* ppp read buffer */ #define BUFFER_TYPE_TTY_WR 1 /* tty write buffer */ #define BUFFER_TYPE_DEV_WR 2 /* ppp write buffer */ #define BUFFER_TYPE_TTY_RD 3 /* tty read buffer */ #define BUFFER_TYPE_VJ 4 /* vj compression buffer */ /* Define this string only once for all macro invocations */ static char ppp_warning[] = KERN_WARNING "PPP: ALERT! not INUSE! %d\n"; static char szVersion[] = PPP_VERSION; /* * Information for the protocol decoder */ typedef int (*pfn_proto) (struct ppp *, __u16, __u8 *, int); typedef struct ppp_proto_struct { int proto; pfn_proto func; } ppp_proto_type; static ppp_proto_type proto_list[] = { { PPP_IP, rcv_proto_ip }, { PPP_IPX, rcv_proto_ipx }, { PPP_VJC_COMP, rcv_proto_vjc_comp }, { PPP_VJC_UNCOMP, rcv_proto_vjc_uncomp }, { PPP_LQR, rcv_proto_lqr }, { PPP_CCP, rcv_proto_ccp }, { 0, rcv_proto_unknown } /* !!! MUST BE LAST !!! */ }; __u16 ppp_crc16_table[256] = { 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf, 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7, 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e, 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876, 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd, 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5, 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c, 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974, 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb, 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3, 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a, 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72, 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9, 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1, 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738, 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70, 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7, 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff, 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036, 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e, 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5, 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd, 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134, 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c, 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3, 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb, 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232, 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a, 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1, 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9, 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330, 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78 }; #ifdef CHECK_CHARACTERS static __u32 paritytab[8] = { 0x96696996, 0x69969669, 0x69969669, 0x96696996, 0x69969669, 0x96696996, 0x96696996, 0x69969669 }; #endif /* local function to store a value into the LQR frame */ extern inline __u8 * store_long (register __u8 *p, register int value) { *p++ = (__u8) (value >> 24); *p++ = (__u8) (value >> 16); *p++ = (__u8) (value >> 8); *p++ = (__u8) value; return p; } /************************************************************* * INITIALIZATION *************************************************************/ /* This procedure is called once and once only to define who we are to * the operating system and the various procedures that it may use in * accessing the ppp protocol. */ static int ppp_first_time (void) { static struct tty_ldisc ppp_ldisc; int status; printk (KERN_INFO "PPP: version %s (dynamic channel allocation)" "\n", szVersion); #ifndef MODULE /* slhc module logic has its own copyright announcement */ printk (KERN_INFO "TCP compression code copyright 1989 Regents of the " "University of California\n"); #endif printk (KERN_INFO "PPP Dynamic channel allocation code copyright 1995 " "Caldera, Inc.\n"); /* * Register the tty discipline */ (void) memset (&ppp_ldisc, 0, sizeof (ppp_ldisc)); ppp_ldisc.magic = TTY_LDISC_MAGIC; ppp_ldisc.open = ppp_tty_open; ppp_ldisc.close = ppp_tty_close; ppp_ldisc.read = ppp_tty_read; ppp_ldisc.write = ppp_tty_write; ppp_ldisc.ioctl = ppp_tty_ioctl; ppp_ldisc.select = ppp_tty_select; ppp_ldisc.receive_room = ppp_tty_room; ppp_ldisc.receive_buf = ppp_tty_receive; ppp_ldisc.write_wakeup = ppp_tty_wakeup; status = tty_register_ldisc (N_PPP, &ppp_ldisc); if (status == 0) printk (KERN_INFO "PPP line discipline registered.\n"); else printk (KERN_ERR "error registering line discipline: %d\n", status); return status; } /************************************************************* * INITIALIZATION *************************************************************/ /* called when the device is actually created */ static int ppp_init_dev (struct device *dev) { int indx; dev->hard_header = ppp_dev_header; dev->rebuild_header = ppp_dev_rebuild; dev->hard_header_len = PPP_HARD_HDR_LEN; /* device INFO */ dev->mtu = PPP_MTU; dev->hard_start_xmit = ppp_dev_xmit; dev->open = ppp_dev_open; dev->stop = ppp_dev_close; dev->get_stats = ppp_dev_stats; dev->do_ioctl = ppp_dev_ioctl; dev->addr_len = 0; dev->tx_queue_len = 10; dev->type = ARPHRD_PPP; for (indx = 0; indx < DEV_NUMBUFFS; indx++) skb_queue_head_init (&dev->buffs[indx]); /* New-style flags */ #ifdef IFF_SOFTHEADERS /* Needed to make SOCK_PACKET work correctly in * memory fussy kernels. */ dev->flags = IFF_POINTOPOINT|IFF_SOFTHEADERS; #else dev->flags = IFF_POINTOPOINT; #endif dev->family = AF_INET; dev->pa_addr = 0; dev->pa_brdaddr = 0; dev->pa_mask = 0; dev->pa_alen = 4; /* sizeof (__u32) */ return 0; } /* * Local procedure to initialize the ppp structure */ static void ppp_init_ctrl_blk (register struct ppp *ppp) { ppp->magic = PPP_MAGIC; ppp->toss = 0xE0; ppp->escape = 0; ppp->flags = 0; ppp->mtu = PPP_MTU; ppp->mru = PPP_MRU; memset (ppp->xmit_async_map, 0, sizeof (ppp->xmit_async_map)); ppp->xmit_async_map[0] = 0xffffffff; ppp->xmit_async_map[3] = 0x60000000; ppp->recv_async_map = 0x00000000; ppp->rbuf = NULL; ppp->wbuf = NULL; ppp->ubuf = NULL; ppp->cbuf = NULL; ppp->slcomp = NULL; ppp->read_wait = NULL; ppp->write_wait = NULL; ppp->last_xmit = jiffies - flag_time; /* clear statistics */ memset (&ppp->stats, '\0', sizeof (struct pppstat)); /* Reset the demand dial information */ ppp->ddinfo.xmit_idle= /* time since last NP packet sent */ ppp->ddinfo.recv_idle=jiffies; /* time since last NP packet received */ /* PPP compression data */ ppp->sc_xc_state = ppp->sc_rc_state = NULL; } static struct symbol_table ppp_syms = { #include <linux/symtab_begin.h> X(ppp_register_compressor), X(ppp_unregister_compressor), X(ppp_crc16_table), #include <linux/symtab_end.h> }; /* called at boot/load time for each ppp device defined in the kernel */ #ifndef MODULE int ppp_init (struct device *dev) { static int first_time = 1; int answer = 0; if (first_time) { first_time = 0; answer = ppp_first_time(); if (answer == 0) (void) register_symtab (&ppp_syms); } if (answer == 0) answer = -ENODEV; return answer; } #endif /* * Routine to allocate a buffer for later use by the driver. */ static struct ppp_buffer * ppp_alloc_buf (int size, int type) { struct ppp_buffer *buf; buf = (struct ppp_buffer *) kmalloc (size + sizeof (struct ppp_buffer), GFP_ATOMIC); if (buf != NULL) { buf->size = size - 1; /* Mask for the buffer size */ buf->type = type; buf->locked = 0; buf->count = 0; buf->head = 0; buf->tail = 0; buf->fcs = PPP_INITFCS; } return (buf); } /* * Routine to release the allocated buffer. */ static void ppp_free_buf (struct ppp_buffer *ptr) { if (ptr != NULL) kfree (ptr); } /* * Lock the indicated transmit buffer */ extern inline int lock_buffer (register struct ppp_buffer *buf) { register int state; int flags; /* * Save the current state and if free then set it to the "busy" state */ save_flags (flags); cli (); state = buf->locked; if (state == 0) buf->locked = 2; restore_flags (flags); return (state); } /* * MTU has been changed by the IP layer. Unfortunately we are not told * about this, but we spot it ourselves and fix things up. We could be * in an upcall from the tty driver, or in an ip packet queue. */ static int ppp_changedmtu (struct ppp *ppp, int new_mtu, int new_mru) { struct device *dev; struct ppp_buffer *new_rbuf; struct ppp_buffer *new_wbuf; struct ppp_buffer *new_cbuf; struct ppp_buffer *new_tbuf; struct ppp_buffer *old_rbuf; struct ppp_buffer *old_wbuf; struct ppp_buffer *old_cbuf; struct ppp_buffer *old_tbuf; int mtu, mru; /* * Allocate the buffer from the kernel for the data */ dev = ppp2dev (ppp); mru = new_mru; /* allow for possible escaping of every character */ mtu = (new_mtu * 2) + 20; /* RFC 1331, section 7.2 says the minimum value is 1500 bytes */ if (mru < PPP_MRU) mru = PPP_MRU; mru += 10; if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp: channel %s mtu = %d, mru = %d\n", dev->name, new_mtu, new_mru); new_wbuf = ppp_alloc_buf (mtu+PPP_HARD_HDR_LEN, BUFFER_TYPE_DEV_WR); new_tbuf = ppp_alloc_buf ((PPP_MTU * 2) + 24, BUFFER_TYPE_TTY_WR); new_rbuf = ppp_alloc_buf (mru + 84, BUFFER_TYPE_DEV_RD); new_cbuf = ppp_alloc_buf (mru+PPP_HARD_HDR_LEN, BUFFER_TYPE_VJ); /* * If the buffers failed to allocate then complain and release the partial * allocations. */ if (new_wbuf == NULL || new_tbuf == NULL || new_rbuf == NULL || new_cbuf == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp: failed to allocate new buffers\n"); ppp_free_buf (new_wbuf); ppp_free_buf (new_tbuf); ppp_free_buf (new_rbuf); ppp_free_buf (new_cbuf); return 0; } /* * Update the pointers to the new buffer structures. */ cli (); old_wbuf = ppp->wbuf; old_rbuf = ppp->rbuf; old_cbuf = ppp->cbuf; old_tbuf = ppp->tbuf; ppp->wbuf = new_wbuf; ppp->rbuf = new_rbuf; ppp->cbuf = new_cbuf; ppp->tbuf = new_tbuf; ppp->rbuf->size -= 80; /* reserve space for vj header expansion */ dev->mem_start = (unsigned long) buf_base (new_wbuf); dev->mem_end = (unsigned long) (dev->mem_start + mtu); dev->rmem_start = (unsigned long) buf_base (new_rbuf); dev->rmem_end = (unsigned long) (dev->rmem_start + mru); /* * Update the parameters for the new buffer sizes */ ppp->toss = 0xE0; /* To ignore characters until new FLAG */ ppp->escape = 0; /* No pending escape character */ dev->mtu = ppp->mtu = new_mtu; ppp->mru = new_mru; ppp->s1buf = NULL; ppp->s2buf = NULL; ppp->xbuf = NULL; ppp->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); ppp->flags &= ~SC_XMIT_BUSY; sti (); /* * Release old buffer pointers */ ppp_free_buf (old_rbuf); ppp_free_buf (old_wbuf); ppp_free_buf (old_cbuf); ppp_free_buf (old_tbuf); return 1; } /* * CCP is down; free (de)compressor state if necessary. */ static void ppp_ccp_closed (struct ppp *ppp) { if (ppp->sc_xc_state) { (*ppp->sc_xcomp->comp_free) (ppp->sc_xc_state); ppp->sc_xc_state = NULL; } if (ppp->sc_rc_state) { (*ppp->sc_rcomp->decomp_free) (ppp->sc_rc_state); ppp->sc_rc_state = NULL; } } /* * Called to release all of the information in the current PPP structure. * * It is called when the ppp device goes down or if it is unable to go * up. */ static void ppp_release (struct ppp *ppp) { struct tty_struct *tty; struct device *dev; tty = ppp2tty (ppp); dev = ppp2dev (ppp); ppp_ccp_closed (ppp); /* Ensure that the pppd process is not hanging on select() */ wake_up_interruptible (&ppp->read_wait); wake_up_interruptible (&ppp->write_wait); if (tty != NULL && tty->disc_data == ppp) tty->disc_data = NULL; /* Break the tty->ppp link */ if (dev && dev->flags & IFF_UP) { dev_close (dev); /* close the device properly */ dev->flags &= ~IFF_UP; /* prevent recursion */ } ppp_free_buf (ppp->rbuf); ppp_free_buf (ppp->wbuf); ppp_free_buf (ppp->cbuf); ppp_free_buf (ppp->ubuf); ppp_free_buf (ppp->tbuf); ppp->rbuf = ppp->wbuf = ppp->cbuf = ppp->tbuf = ppp->xbuf = ppp->s1buf = ppp->s2buf = ppp->ubuf = NULL; if (ppp->slcomp) { slhc_free (ppp->slcomp); ppp->slcomp = NULL; } ppp->inuse = 0; ppp->tty = NULL; } /* * Device callback. * * Called when the PPP device goes down in response to an ifconfig request. */ static void ppp_tty_close_local (struct tty_struct *tty, int sc_xfer) { struct ppp *ppp = tty2ppp (tty); if (ppp != NULL) { if (ppp->magic != PPP_MAGIC) { if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp: trying to close unopened tty!\n"); } else { CHECK_PPP_VOID(); ppp->sc_xfer = sc_xfer; if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp: channel %s closing.\n", ppp2dev(ppp) -> name); ppp_release (ppp); MOD_DEC_USE_COUNT; } } } static void ppp_tty_close (struct tty_struct *tty) { ppp_tty_close_local (tty, 0); } /* * TTY callback. * * Called when the tty discipline is switched to PPP. */ static int ppp_tty_open (struct tty_struct *tty) { struct ppp *ppp = tty2ppp (tty); int indx; /* * There should not be an existing table for this slot. */ if (ppp) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_tty_open: gack! tty already associated to %s!\n", ppp->magic == PPP_MAGIC ? ppp2dev(ppp)->name : "unknown"); return -EEXIST; } /* * Allocate the structure from the system */ ppp = ppp_find(current->pid); if (ppp == NULL) { ppp = ppp_find(0); if (ppp == NULL) ppp = ppp_alloc(); } if (ppp == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_tty_open: couldn't allocate ppp channel\n"); return -ENFILE; } /* * Initialize the control block */ ppp_init_ctrl_blk (ppp); ppp->tty = tty; tty->disc_data = ppp; /* * Flush any pending characters in the driver and discipline. */ if (tty->ldisc.flush_buffer) tty->ldisc.flush_buffer (tty); if (tty->driver.flush_buffer) tty->driver.flush_buffer (tty); /* * Allocate space for the default VJ header compression slots */ ppp->slcomp = slhc_init (16, 16); if (ppp->slcomp == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_tty_open: no space for compression buffers!\n"); ppp_release (ppp); return -ENOMEM; } /* * Allocate space for the MTU and MRU buffers */ if (ppp_changedmtu (ppp, ppp2dev(ppp)->mtu, ppp->mru) == 0) { ppp_release (ppp); return -ENOMEM; } /* * Allocate space for a user level buffer */ ppp->ubuf = ppp_alloc_buf (RBUFSIZE, BUFFER_TYPE_TTY_RD); if (ppp->ubuf == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_tty_open: no space for user receive buffer\n"); ppp_release (ppp); return -ENOMEM; } if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp: channel %s open\n", ppp2dev(ppp)->name); for (indx = 0; indx < NUM_NP; ++indx) ppp->sc_npmode[indx] = NPMODE_PASS; MOD_INC_USE_COUNT; return (ppp->line); } /* * Local function to send the next portion of the buffer. * * Called by the tty driver's tty_wakeup function should it be entered * because the partial buffer was transmitted. * * Called by kick_tty to send the initial portion of the buffer. * * Completion processing of the buffer transmission is handled here. */ static void ppp_tty_wakeup_code (struct ppp *ppp, struct tty_struct *tty, struct ppp_buffer *xbuf) { register int count, actual; /* * Prevent re-entrancy by ensuring that this routine is called only once. */ cli (); if (ppp->flags & SC_XMIT_BUSY) { sti (); return; } ppp->flags |= SC_XMIT_BUSY; sti (); /* * Send the next block of data to the modem */ count = xbuf->count - xbuf->tail; actual = tty->driver.write (tty, 0, buf_base (xbuf) + xbuf->tail, count); /* * Terminate transmission of any block which may have an error. * This could occur should the carrier drop. */ if (actual < 0) { ppp->stats.ppp_oerrors++; actual = count; } else ppp->bytes_sent += actual; /* * If the buffer has been transmitted then clear the indicators. */ xbuf->tail += actual; if (actual == count) { xbuf = NULL; ppp->flags &= ~SC_XMIT_BUSY; /* * Complete the transmission on the current buffer. */ xbuf = ppp->xbuf; if (xbuf != NULL) { tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); xbuf->locked = 0; ppp->xbuf = NULL; /* * If the completed buffer came from the device write, then complete the * transmission block. */ if (ppp2dev (ppp) -> flags & IFF_UP) { if (xbuf->type == BUFFER_TYPE_DEV_WR) ppp2dev (ppp)->tbusy = 0; mark_bh (NET_BH); } /* * Wake up the transmission queue for all completion events. */ wake_up_interruptible (&ppp->write_wait); /* * Look at the priorities. Choose a daemon write over the device driver. */ cli(); xbuf = ppp->s1buf; ppp->s1buf = NULL; if (xbuf == NULL) { xbuf = ppp->s2buf; ppp->s2buf = NULL; } sti(); /* * If there is a pending buffer then transmit it now. */ if (xbuf != NULL) { ppp->flags &= ~SC_XMIT_BUSY; ppp_kick_tty (ppp, xbuf); return; } } } /* * Clear the re-entry flag */ ppp->flags &= ~SC_XMIT_BUSY; } /* * This function is called by the tty driver when the transmit buffer has * additional space. It is used by the ppp code to continue to transmit * the current buffer should the buffer have been partially sent. * * In addition, it is used to send the first part of the buffer since the * logic and the inter-locking would be identical. */ static void ppp_tty_wakeup (struct tty_struct *tty) { struct ppp_buffer *xbuf; struct ppp *ppp = tty2ppp (tty); if (!ppp) return; if (ppp->magic != PPP_MAGIC) return; /* * Ensure that there is a transmission pending. Clear the re-entry flag if * there is no pending buffer. Otherwise, send the buffer. */ xbuf = ppp->xbuf; if (xbuf == NULL) tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); else ppp_tty_wakeup_code (ppp, tty, xbuf); } /* * This function is called to transmit a buffer to the remote. The buffer * is placed on the pending queue if there is presently a buffer being * sent or it is transmitted with the aid of ppp_tty_wakeup. */ static void ppp_kick_tty (struct ppp *ppp, struct ppp_buffer *xbuf) { register int flags; /* * Hold interrupts. */ save_flags (flags); cli (); /* * Control the flags which are best performed with the interrupts masked. */ xbuf->locked = 1; xbuf->tail = 0; /* * If the transmitter is busy then place the buffer on the appropriate * priority queue. */ if (ppp->xbuf != NULL) { if (xbuf->type == BUFFER_TYPE_TTY_WR) ppp->s1buf = xbuf; else ppp->s2buf = xbuf; restore_flags (flags); return; } /* * If the transmitter is not busy then this is the highest priority frame */ ppp->flags &= ~SC_XMIT_BUSY; ppp->tty->flags |= (1 << TTY_DO_WRITE_WAKEUP); ppp->xbuf = xbuf; restore_flags (flags); /* * Do the "tty wakeup_code" to actually send this buffer. */ ppp_tty_wakeup_code (ppp, ppp2tty (ppp), xbuf); } /************************************************************* * TTY INPUT * The following functions handle input that arrives from * the TTY. It recognizes PPP frames and either hands them * to the network layer or queues them for delivery to a * user process reading this TTY. *************************************************************/ /* * Callback function from tty driver. Return the amount of space left * in the receiver's buffer to decide if remote transmitter is to be * throttled. */ static int ppp_tty_room (struct tty_struct *tty) { return 65536; /* We can handle an infinite amount of data. :-) */ } /* * Callback function when data is available at the tty driver. */ static void ppp_tty_receive (struct tty_struct *tty, const __u8 * data, char *flags, int count) { register struct ppp *ppp = tty2ppp (tty); register struct ppp_buffer *buf = NULL; __u8 chr; /* * Fetch the pointer to the buffer. Be careful about race conditions. */ if (ppp != NULL) buf = ppp->rbuf; if (buf == NULL) return; /* * Verify the table pointer and ensure that the line is * still in PPP discipline. */ if (ppp->magic != PPP_MAGIC) { if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "PPP: handler called but couldn't find " "PPP struct.\n"); return; } CHECK_PPP_VOID (); /* * Print the buffer if desired */ if (ppp->flags & SC_LOG_RAWIN) ppp_print_buffer ("receive buffer", data, count); /* * Collect the character and error condition for the character. Set the toss * flag for the first character error. */ while (count-- > 0) { ppp->bytes_rcvd++; chr = *data++; if (flags) { if (*flags && ppp->toss == 0) ppp->toss = *flags; ++flags; } /* * Set the flags for 8 data bits and no parity. * * Actually, it sets the flags for d7 being 0/1 and parity being even/odd * so that the normal processing would have all flags set at the end of the * session. A missing flag bit would denote an error condition. */ #ifdef CHECK_CHARACTERS if (chr & 0x80) ppp->flags |= SC_RCV_B7_1; else ppp->flags |= SC_RCV_B7_0; if (paritytab[chr >> 5] & (1 << (chr & 0x1F))) ppp->flags |= SC_RCV_ODDP; else ppp->flags |= SC_RCV_EVNP; #endif /* * Branch on the character. Process the escape character. The sequence ESC ESC * is defined to be ESC. */ switch (chr) { case PPP_ESCAPE: /* PPP_ESCAPE: invert bit in next character */ ppp->escape = PPP_TRANS; break; /* * FLAG. This is the end of the block. If the block terminated by ESC FLAG, * then the block is to be ignored. In addition, characters before the very * first FLAG are also tossed by this procedure. */ case PPP_FLAG: /* PPP_FLAG: end of frame */ ppp->stats.ppp_ibytes += ppp->rbuf->count; if (ppp->escape) ppp->toss |= 0x80; /* * Process frames which are not to be ignored. If the processing failed, * then clean up the VJ tables. */ if ((ppp->toss & 0x80) != 0 || ppp_doframe (ppp) == 0) { slhc_toss (ppp->slcomp); } /* * Reset all indicators for the new frame to follow. */ buf->count = 0; buf->fcs = PPP_INITFCS; ppp->escape = 0; ppp->toss = 0; break; /* * All other characters in the data come here. If the character is in the * receive mask then ignore the character. */ default: if (in_rmap (ppp, chr)) break; /* * Adjust the character and if the frame is to be discarded then simply * ignore the character until the ending FLAG is received. */ chr ^= ppp->escape; ppp->escape = 0; if (ppp->toss != 0) break; /* * If the count sent is within reason then store the character, bump the * count, and update the FCS for the character. */ if (buf->count < buf->size) { buf_base (buf)[buf->count++] = chr; buf->fcs = PPP_FCS (buf->fcs, chr); break; } /* * The peer sent too much data. Set the flags to discard the current frame * and wait for the re-synchronization FLAG to be sent. */ ppp->stats.ppp_ierrors++; ppp->toss |= 0xC0; break; } } } /* * Put the input frame into the networking system for the indicated protocol */ static int ppp_rcv_rx (struct ppp *ppp, __u16 proto, __u8 * data, int count) { sk_buff *skb = dev_alloc_skb (count); /* * Generate a skb buffer for the new frame. */ if (skb == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_do_ip: packet dropped on %s (no memory)!\n", ppp2dev (ppp)->name); return 0; } /* * Move the received data from the input buffer to the skb buffer. */ skb->dev = ppp2dev (ppp); /* We are the device */ skb->protocol = proto; skb->mac.raw = skb_data(skb); memcpy (skb_put(skb,count), data, count); /* move data */ /* * Tag the frame and kick it to the proper receive routine */ skb->free = 1; ppp->ddinfo.recv_idle = jiffies; netif_rx (skb); return 1; } /* * Process the receipt of an IP frame */ static int rcv_proto_ip (struct ppp *ppp, __u16 proto, __u8 * data, int count) { if ((ppp2dev (ppp)->flags & IFF_UP) && (count > 0)) if (ppp->sc_npmode[NP_IP] == NPMODE_PASS) return ppp_rcv_rx (ppp, htons (ETH_P_IP), data, count); return 0; } /* * Process the receipt of an IPX frame */ static int rcv_proto_ipx (struct ppp *ppp, __u16 proto, __u8 * data, int count) { if (((ppp2dev (ppp)->flags & IFF_UP) != 0) && (count > 0)) return ppp_rcv_rx (ppp, htons (ETH_P_IPX), data, count); return 0; } /* * Process the receipt of an VJ Compressed frame */ static int rcv_proto_vjc_comp (struct ppp *ppp, __u16 proto, __u8 *data, int count) { if ((ppp->flags & SC_REJ_COMP_TCP) == 0) { int new_count = slhc_uncompress (ppp->slcomp, data, count); if (new_count >= 0) { return rcv_proto_ip (ppp, PPP_IP, data, new_count); } if (ppp->flags & SC_DEBUG) printk (KERN_NOTICE "ppp: error in VJ decompression\n"); } return 0; } /* * Process the receipt of an VJ Un-compressed frame */ static int rcv_proto_vjc_uncomp (struct ppp *ppp, __u16 proto, __u8 *data, int count) { if ((ppp->flags & SC_REJ_COMP_TCP) == 0) { if (slhc_remember (ppp->slcomp, data, count) > 0) { return rcv_proto_ip (ppp, PPP_IP, data, count); } if (ppp->flags & SC_DEBUG) printk (KERN_NOTICE "ppp: error in VJ memorizing\n"); } return 0; } /* * Receive all unclassified protocols. */ static int rcv_proto_unknown (struct ppp *ppp, __u16 proto, __u8 *data, int len) { int totlen; register int current_idx; #define PUTC(c) \ { \ buf_base (ppp->ubuf) [current_idx++] = (__u8) (c); \ current_idx &= ppp->ubuf->size; \ if (current_idx == ppp->ubuf->tail) \ goto failure; \ } /* * The total length includes the protocol data. * Lock the user information buffer. */ if (set_bit (0, &ppp->ubuf->locked)) { if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_us_queue: can't get lock\n"); } else { current_idx = ppp->ubuf->head; /* * Insert the buffer length (not counted), the protocol, and the data */ totlen = len + 2; PUTC (totlen >> 8); PUTC (totlen); PUTC (proto >> 8); PUTC (proto); totlen -= 2; while (totlen-- > 0) { PUTC (*data++); } #undef PUTC /* * The frame is complete. Update the head pointer and wakeup the pppd * process. */ ppp->ubuf->head = current_idx; clear_bit (0, &ppp->ubuf->locked); wake_up_interruptible (&ppp->read_wait); if (ppp->tty->fasync != NULL) kill_fasync (ppp->tty->fasync, SIGIO); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp: successfully queued %d bytes, flags = %x\n", len + 2, ppp->flags); return 1; /* * The buffer is full. Unlock the header */ failure: clear_bit (0, &ppp->ubuf->locked); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_us_queue: ran out of buffer space.\n"); } /* * Discard the frame. There are no takers for this protocol. */ if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp: dropping packet on the floor.\n"); slhc_toss (ppp->slcomp); return 0; } /* * Handle a CCP packet. * * The CCP packet is passed along to the pppd process just like any * other PPP frame. The difference is that some processing needs to be * immediate or the compressors will become confused on the peer. */ static void ppp_proto_ccp (struct ppp *ppp, __u8 *dp, int len, int rcvd) { int slen = CCP_LENGTH(dp); __u8 *opt = dp + CCP_HDRLEN; int opt_len = slen - CCP_HDRLEN; if (slen > len) return; switch (CCP_CODE(dp)) { case CCP_CONFREQ: case CCP_TERMREQ: case CCP_TERMACK: /* * CCP must be going down - disable compression */ if (ppp->flags & SC_CCP_UP) { ppp->flags &= ~(SC_CCP_UP | SC_COMP_RUN | SC_DECOMP_RUN); } break; case CCP_CONFACK: if ((ppp->flags & SC_CCP_OPEN) == 0) break; if (ppp->flags & SC_CCP_UP) break; if (slen < (CCP_HDRLEN + CCP_OPT_MINLEN)) break; if (slen < (CCP_OPT_LENGTH (opt) + CCP_HDRLEN)) break; /* * we're agreeing to send compressed packets. */ if (!rcvd) { if (ppp->sc_xc_state == NULL) break; if ((*ppp->sc_xcomp->comp_init) (ppp->sc_xc_state, opt, opt_len, ppp2dev (ppp)->base_addr, 0, ppp->flags)) ppp->flags |= SC_COMP_RUN; break; } /* * peer is agreeing to send compressed packets. */ if (ppp->sc_rc_state == NULL) break; if ((*ppp->sc_rcomp->decomp_init) (ppp->sc_rc_state, opt, opt_len, ppp2dev (ppp)->base_addr, 0, ppp->mru, ppp->flags)) { ppp->flags |= SC_DECOMP_RUN; ppp->flags &= ~(SC_DC_ERROR | SC_DC_FERROR); } break; /* * The protocol sequence is complete at this end */ case CCP_RESETACK: if ((ppp->flags & SC_CCP_UP) == 0) break; if (!rcvd) { if (ppp->sc_xc_state && (ppp->flags & SC_COMP_RUN)) (*ppp->sc_xcomp->comp_reset)(ppp->sc_xc_state); } else { if (ppp->sc_rc_state && (ppp->flags & SC_DECOMP_RUN)) { (*ppp->sc_rcomp->decomp_reset)(ppp->sc_rc_state); ppp->flags &= ~SC_DC_ERROR; } } break; } } static int rcv_proto_ccp (struct ppp *ppp, __u16 proto, __u8 *dp, int len) { ppp_proto_ccp (ppp, dp, len, 1); return rcv_proto_unknown (ppp, proto, dp, len); } /* * Handle a LQR packet. */ static int rcv_proto_lqr (struct ppp *ppp, __u16 proto, __u8 * data, int len) { return rcv_proto_unknown (ppp, proto, data, len); } /* on entry, a received frame is in ppp->rbuf.bufr check it and dispose as appropriate */ static void ppp_doframe_lower (struct ppp *ppp, __u8 *data, int count) { __u16 proto = PPP_PROTOCOL (data); ppp_proto_type *proto_ptr; /* * Ignore empty frames */ if (count <= 4) return; /* * Count the frame and print it */ ++ppp->stats.ppp_ipackets; if (ppp->flags & SC_LOG_INPKT) ppp_print_buffer ("receive frame", data, count); /* * Find the procedure to handle this protocol. The last one is marked * as a protocol 0 which is the 'catch-all' to feed it to the pppd daemon. */ proto_ptr = proto_list; while (proto_ptr->proto != 0 && proto_ptr->proto != proto) ++proto_ptr; /* * Update the appropriate statistic counter. */ if ((*proto_ptr->func) (ppp, proto, &data[PPP_HARD_HDR_LEN], count - PPP_HARD_HDR_LEN)) ppp->stats.ppp_ioctects += count; else ++ppp->stats.ppp_discards; } /* on entry, a received frame is in ppp->rbuf.bufr check it and dispose as appropriate */ static int ppp_doframe (struct ppp *ppp) { __u8 *data = buf_base (ppp->rbuf); int count = ppp->rbuf->count; int addr, ctrl, proto; int new_count; __u8 *new_data; #ifndef NO_RMK_TEMP_FIX int malloced_data; #endif /* * If there is a pending error from the receiver then log it and discard * the damaged frame. */ if (ppp->toss) { if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp_toss: tossing frame, reason = %d\n", ppp->toss); ppp->stats.ppp_ierrors++; return 0; } /* * An empty frame is ignored. This occurs if the FLAG sequence precedes and * follows each frame. */ if (count == 0) return 1; /* * Generate an error if the frame is too small. */ if (count < PPP_HARD_HDR_LEN) { if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp: got runt ppp frame, %d chars\n", count); slhc_toss (ppp->slcomp); ppp->stats.ppp_ierrors++; return 1; } /* * Verify the CRC of the frame and discard the CRC characters from the * end of the buffer. */ if (ppp->rbuf->fcs != PPP_GOODFCS) { if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp: frame with bad fcs, excess = %x\n", ppp->rbuf->fcs ^ PPP_GOODFCS); ppp->stats.ppp_ierrors++; return 0; } count -= 2; /* ignore the fcs characters */ /* * Ignore the leading ADDRESS and CONTROL fields in the frame. */ addr = PPP_ALLSTATIONS; ctrl = PPP_UI; if ((data[0] == PPP_ALLSTATIONS) && (data[1] == PPP_UI)) { data += 2; count -= 2; } /* * Obtain the protocol from the frame */ proto = (__u16) *data++; if ((proto & 1) == 0) { proto = (proto << 8) | (__u16) *data++; --count; } /* * Rewrite the header with the full information. This may encroach upon * the 'filler' area in the buffer header. This is the purpose for the * filler. */ *(--data) = proto; *(--data) = proto >> 8; *(--data) = ctrl; *(--data) = addr; count += 3; #ifndef NO_RMK_TEMP_FIX /* * rmk: should make sure that the packet received is on a word boundary. * this is a temporary fix!!! */ if ((int)data & 3) { new_data = kmalloc (ppp->mru + 4, GFP_ATOMIC); /* would like to have 'count' here */ memcpy (new_data, data, count); data = new_data; malloced_data = 1; } else malloced_data = 0; #endif /* * Process the active decompressor. */ if ((ppp->sc_rc_state != (void *) 0) && (ppp->flags & SC_DECOMP_RUN) && ((ppp->flags & (SC_DC_FERROR | SC_DC_ERROR)) == 0)) { if (proto == PPP_COMP) { /* * If the frame is compressed then decompress it. */ new_data = kmalloc (ppp->mru + 4, GFP_ATOMIC); if (new_data == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_doframe: no memory\n"); slhc_toss (ppp->slcomp); (*ppp->sc_rcomp->incomp) (ppp->sc_rc_state, data, count); #ifndef NO_RMK_TEMP_FIX if (malloced_data) kfree (data); #endif return 1; } /* * Decompress the frame */ new_count = bsd_decompress (ppp->sc_rc_state, data, count, new_data, ppp->mru + 4); switch (new_count) { default: ppp_doframe_lower (ppp, new_data, new_count); kfree (new_data); #ifndef NO_RMK_TEMP_FIX if (malloced_data) kfree (data); #endif return 1; case DECOMP_OK: break; case DECOMP_ERROR: ppp->flags |= SC_DC_ERROR; break; case DECOMP_FATALERROR: ppp->flags |= SC_DC_FERROR; break; } /* * Log the error condition and discard the frame. */ if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_proto_comp: " "decompress err %d\n", new_count); kfree (new_data); slhc_toss (ppp->slcomp); #ifndef NO_RMK_TEMP_FIX if (malloced_data) kfree (data); #endif return 1; } /* * The frame is not special. Pass it through the compressor without * actually compressing the data */ (*ppp->sc_rcomp->incomp) (ppp->sc_rc_state, data, count); } /* * Process the uncompressed frame. */ ppp_doframe_lower (ppp, data, count); #ifndef NO_RMK_TEMP_FIX if (malloced_data) kfree (data); #endif return 1; } /************************************************************* * LINE DISCIPLINE SUPPORT * The following functions form support user programs * which read and write data on a TTY with the PPP line * discipline. Reading is done from a circular queue, * filled by the lower TTY levels. *************************************************************/ /* read a PPP frame from the us_rbuff circular buffer, waiting if necessary */ static int ppp_tty_read (struct tty_struct *tty, struct file *file, __u8 * buf, unsigned int nr) { struct ppp *ppp = tty2ppp (tty); __u8 c; int len, indx; #define GETC(c) \ { \ c = buf_base (ppp->ubuf) [ppp->ubuf->tail++]; \ ppp->ubuf->tail &= ppp->ubuf->size; \ } /* * Validate the pointers */ if (!ppp) return -EIO; if (ppp->magic != PPP_MAGIC) return -EIO; CHECK_PPP (-ENXIO); if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_tty_read: called buf=%p nr=%u\n", buf, nr); /* * Acquire the read lock. */ for (;;) { ppp = tty2ppp (tty); if (!ppp || ppp->magic != PPP_MAGIC || !ppp->inuse) return 0; if (set_bit (0, &ppp->ubuf->locked) != 0) { if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_tty_read: sleeping(ubuf)\n"); current->timeout = 0; current->state = TASK_INTERRUPTIBLE; schedule (); if (current->signal & ~current->blocked) return -EINTR; continue; } /* * Before we attempt to write the frame to the user, ensure that the * user has access to the pages for the total buffer length. */ indx = verify_area (VERIFY_WRITE, buf, nr); if (indx != 0) return (indx); /* * Fetch the length of the buffer from the first two bytes. */ if (ppp->ubuf->head == ppp->ubuf->tail) len = 0; else { GETC (c); len = c << 8; GETC (c); len += c; } /* * If there is no length then wait for the data to arrive. */ if (len == 0) { /* no data */ clear_bit (0, &ppp->ubuf->locked); if (file->f_flags & O_NONBLOCK) { if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_tty_read: no data " "(EAGAIN)\n"); return -EAGAIN; } current->timeout = 0; if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_tty_read: sleeping(read_wait)\n"); interruptible_sleep_on (&ppp->read_wait); if (current->signal & ~current->blocked) return -EINTR; continue; } /* * Reset the time of the last read operation. */ if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_tty_read: len = %d\n", len); /* * Ensure that the frame will fit within the caller's buffer. If not, then * discard the frame from the input buffer. */ if (len + 2 > nr) { /* Can't copy it, update us_rbuff_head */ if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp: read of %u bytes too small for %d " "frame\n", nr, len + 2); ppp->ubuf->tail += len; ppp->ubuf->tail &= ppp->ubuf->size; clear_bit (0, &ppp->ubuf->locked); ppp->stats.ppp_ierrors++; return -EOVERFLOW; } /* * Before we attempt to write the frame to the user, ensure that the * page tables are proper. */ indx = verify_area (VERIFY_WRITE, buf, len + 2); if (indx != 0) { ppp->ubuf->tail += len; ppp->ubuf->tail &= ppp->ubuf->size; clear_bit (0, &ppp->ubuf->locked); return (indx); } /* * Fake the insertion of the ADDRESS and CONTROL information because these * were not saved in the buffer. */ put_user (PPP_ALLSTATIONS, buf++); put_user (PPP_UI, buf++); indx = len; /* * Copy the received data from the buffer to the caller's area. */ while (indx-- > 0) { GETC (c); put_user (c, buf); ++buf; } clear_bit (0, &ppp->ubuf->locked); len += 2; /* Account for ADDRESS and CONTROL bytes */ if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_tty_read: passing %d bytes up\n", len); return len; } #undef GETC } /* stuff a character into the transmit buffer, using PPP's way of escaping special characters. also, update fcs to take account of new character */ extern inline void ppp_stuff_char (struct ppp *ppp, register struct ppp_buffer *buf, register __u8 chr) { /* * The buffer should not be full. */ if (ppp->flags & SC_DEBUG) { if ((buf->count < 0) || (buf->count > 3000)) printk (KERN_DEBUG "ppp_stuff_char: %x %d\n", (unsigned int) buf->count, (unsigned int) chr); } /* * Update the FCS and if the character needs to be escaped, do it. */ buf->fcs = PPP_FCS (buf->fcs, chr); if (in_xmap (ppp, chr)) { chr ^= PPP_TRANS; ins_char (buf, PPP_ESCAPE); } /* * Add the character to the buffer. */ ins_char (buf, chr); } /* * Procedure to encode the data with the proper escaping and send the * data to the remote system. */ static void ppp_dev_xmit_lower (struct ppp *ppp, struct ppp_buffer *buf, __u8 *data, int count, int non_ip) { __u16 write_fcs; int address, control; int proto; /* * Insert the leading FLAG character */ buf->count = 0; if (non_ip || flag_time == 0) ins_char (buf, PPP_FLAG); else { if (jiffies - ppp->last_xmit > flag_time) ins_char (buf, PPP_FLAG); } ppp->last_xmit = jiffies; buf->fcs = PPP_INITFCS; /* * Emit the address/control information if needed */ address = PPP_ADDRESS (data); control = PPP_CONTROL (data); proto = PPP_PROTOCOL (data); if (address != PPP_ALLSTATIONS || control != PPP_UI || (ppp->flags & SC_COMP_AC) == 0) { ppp_stuff_char (ppp, buf, address); ppp_stuff_char (ppp, buf, control); } /* * Emit the protocol (compressed if possible) */ if ((ppp->flags & SC_COMP_PROT) == 0 || (proto & 0xFF00)) ppp_stuff_char (ppp, buf, proto >> 8); ppp_stuff_char (ppp, buf, proto); /* * Insert the data */ data += 4; count -= 4; while (count-- > 0) ppp_stuff_char (ppp, buf, *data++); /* * Add the trailing CRC and the final flag character */ write_fcs = buf->fcs ^ 0xFFFF; ppp_stuff_char (ppp, buf, write_fcs); ppp_stuff_char (ppp, buf, write_fcs >> 8); if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_dev_xmit_lower: fcs is %hx\n", write_fcs); /* * Add the trailing flag character */ ins_char (buf, PPP_FLAG); /* * Print the buffer */ if (ppp->flags & SC_LOG_FLUSH) ppp_print_buffer ("ppp flush", buf_base (buf), buf->count); else { if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_dev_xmit: writing %d chars\n", buf->count); } /* * Send the block to the tty driver. */ ppp->stats.ppp_obytes += buf->count; ppp_kick_tty (ppp, buf); } /* * Send an frame to the remote with the proper bsd compression. * * Return 0 if frame was queued for transmission. * 1 if frame must be re-queued for later driver support. */ static int ppp_dev_xmit_frame (struct ppp *ppp, struct ppp_buffer *buf, __u8 *data, int count) { int proto; int address, control; __u8 *new_data; int new_count; /* * Print the buffer */ if (ppp->flags & SC_LOG_OUTPKT) ppp_print_buffer ("write frame", data, count); /* * Determine if the frame may be compressed. Attempt to compress the * frame if possible. */ proto = PPP_PROTOCOL (data); address = PPP_ADDRESS (data); control = PPP_CONTROL (data); if (((ppp->flags & SC_COMP_RUN) != 0) && (ppp->sc_xc_state != (void *) 0) && (address == PPP_ALLSTATIONS) && (control == PPP_UI) && (proto != PPP_LCP) && (proto != PPP_CCP)) { new_data = kmalloc (count, GFP_ATOMIC); if (new_data == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_dev_xmit_frame: no memory\n"); return 1; } new_count = bsd_compress (ppp->sc_xc_state, data, new_data, count, count); if (new_count > 0) { ++ppp->stats.ppp_opackets; ppp->stats.ppp_ooctects += new_count; ppp_dev_xmit_lower (ppp, buf, new_data, new_count, 0); kfree (new_data); return 0; } /* * The frame could not be compressed. */ kfree (new_data); } /* * The frame may not be compressed. Update the statistics before the * count field is destroyed. The frame will be transmitted. */ ++ppp->stats.ppp_opackets; ppp->stats.ppp_ooctects += count; /* * Go to the escape encoding */ ppp_dev_xmit_lower (ppp, buf, data, count, !!(proto & 0xFF00)); return 0; } /* * Revise the tty frame for specific protocols. */ static int send_revise_frame (register struct ppp *ppp, __u8 *data, int len) { __u8 *p; switch (PPP_PROTOCOL (data)) { /* * Update the LQR frame with the current MIB information. This saves having * the daemon read old MIB data from the driver. */ case PPP_LQR: len = 48; /* total size of this frame */ p = (__u8 *) &data [40]; /* Point to last two items. */ p = store_long (p, ppp->stats.ppp_opackets + 1); p = store_long (p, ppp->stats.ppp_ooctects + len); break; /* * Outbound compression frames */ case PPP_CCP: ppp_proto_ccp (ppp, data + PPP_HARD_HDR_LEN, len - PPP_HARD_HDR_LEN, 0); break; default: break; } return len; } /* * write a frame with NR chars from BUF to TTY * we have to put the FCS field on ourselves */ static int ppp_tty_write (struct tty_struct *tty, struct file *file, const __u8 * data, unsigned int count) { struct ppp *ppp = tty2ppp (tty); __u8 *new_data; int status; /* * Verify the pointers. */ if (!ppp) return -EIO; if (ppp->magic != PPP_MAGIC) return -EIO; CHECK_PPP (-ENXIO); /* * Ensure that the caller does not wish to send too much. */ if (count > PPP_MTU) { if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp_tty_write: truncating user packet " "from %u to mtu %d\n", count, PPP_MTU); count = PPP_MTU; } /* * Allocate a buffer for the data and fetch it from the user space. */ new_data = kmalloc (count, GFP_KERNEL); if (new_data == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_tty_write: no memory\n"); return 0; } /* * lock this PPP unit so we will be the only writer; * sleep if necessary */ while (lock_buffer (ppp->tbuf) != 0) { current->timeout = 0; if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_tty_write: sleeping\n"); interruptible_sleep_on (&ppp->write_wait); ppp = tty2ppp (tty); if (!ppp || ppp->magic != PPP_MAGIC || !ppp->inuse) { kfree (new_data); return 0; } if (current->signal & ~current->blocked) { kfree (new_data); return -EINTR; } } /* * Ensure that the caller's buffer is valid. */ status = verify_area (VERIFY_READ, data, count); if (status != 0) { kfree (new_data); ppp->tbuf->locked = 0; return status; } memcpy_fromfs (new_data, data, count); /* * Change the LQR frame */ count = send_revise_frame (ppp, new_data, count); /* * Send the data */ ppp_dev_xmit_frame (ppp, ppp->tbuf, new_data, count); kfree (new_data); return (int) count; } /* * Process the BSD compression IOCTL event for the tty device. */ static int ppp_set_compression (struct ppp *ppp, struct ppp_option_data *odp) { struct compressor *cp; struct ppp_option_data data; int error; int nb; __u8 *ptr; __u8 ccp_option[CCP_MAX_OPTION_LENGTH]; /* * Fetch the compression parameters */ error = verify_area (VERIFY_READ, odp, sizeof (data)); if (error == 0) { memcpy_fromfs (&data, odp, sizeof (data)); nb = data.length; ptr = data.ptr; if ((__u32) nb >= (__u32)CCP_MAX_OPTION_LENGTH) nb = CCP_MAX_OPTION_LENGTH; error = verify_area (VERIFY_READ, ptr, nb); } if (error != 0) return error; memcpy_fromfs (ccp_option, ptr, nb); if (ccp_option[1] < 2) /* preliminary check on the length byte */ return (-EINVAL); cp = find_compressor ((int) (unsigned int) (__u8) ccp_option[0]); if (cp != (struct compressor *) 0) { /* * Found a handler for the protocol - try to allocate * a compressor or decompressor. */ error = 0; if (data.transmit) { if (ppp->sc_xc_state != NULL) (*ppp->sc_xcomp->comp_free)(ppp->sc_xc_state); ppp->sc_xcomp = cp; ppp->sc_xc_state = cp->comp_alloc(ccp_option, nb); if (ppp->sc_xc_state == NULL) { if (ppp->flags & SC_DEBUG) printk("ppp%ld: comp_alloc failed\n", ppp2dev (ppp)->base_addr); error = -ENOBUFS; } ppp->flags &= ~SC_COMP_RUN; } else { if (ppp->sc_rc_state != NULL) (*ppp->sc_rcomp->decomp_free)(ppp->sc_rc_state); ppp->sc_rcomp = cp; ppp->sc_rc_state = cp->decomp_alloc(ccp_option, nb); if (ppp->sc_rc_state == NULL) { if (ppp->flags & SC_DEBUG) printk("ppp%ld: decomp_alloc failed\n", ppp2dev (ppp)->base_addr); error = ENOBUFS; } ppp->flags &= ~SC_DECOMP_RUN; } return (error); } if (ppp->flags & SC_DEBUG) printk(KERN_DEBUG "ppp%ld: no compressor for [%x %x %x], %x\n", ppp2dev (ppp)->base_addr, ccp_option[0], ccp_option[1], ccp_option[2], nb); return (-EINVAL); /* no handler found */ } /* * Process the IOCTL event for the tty device. */ static int ppp_tty_ioctl (struct tty_struct *tty, struct file * file, unsigned int param2, unsigned long param3) { struct ppp *ppp = tty2ppp (tty); register int temp_i = 0; int error = 0; /* * Verify the status of the PPP device. */ if (!ppp) return -EBADF; if (ppp->magic != PPP_MAGIC) return -EBADF; CHECK_PPP (-ENXIO); /* * The user must have an euid of root to do these requests. */ if (!suser ()) return -EPERM; /* * Set the MRU value */ switch (param2) { case PPPIOCSMRU: error = verify_area (VERIFY_READ, (void *) param3, sizeof (temp_i)); if (error == 0) { temp_i = get_user ((int *) param3); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: set mru to %x\n", temp_i); if (ppp->mru != temp_i) ppp_changedmtu (ppp, ppp2dev (ppp)->mtu, temp_i); } break; /* * Fetch the flags */ case PPPIOCGFLAGS: error = verify_area (VERIFY_WRITE, (void *) param3, sizeof (temp_i)); if (error == 0) { temp_i = (ppp->flags & SC_MASK); #ifndef CHECK_CHARACTERS /* Don't generate errors if we don't check chars. */ temp_i |= SC_RCV_B7_1 | SC_RCV_B7_0 | SC_RCV_ODDP | SC_RCV_EVNP; #endif put_user (temp_i, (int *) param3); if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_tty_ioctl: get flags: addr %lx flags " "%x\n", param3, temp_i); } break; /* * Set the flags for the various options */ case PPPIOCSFLAGS: error = verify_area (VERIFY_READ, (void *) param3, sizeof (temp_i)); if (error == 0) { temp_i = get_user ((int *) param3) & SC_MASK; temp_i |= (ppp->flags & ~SC_MASK); if ((ppp->flags & SC_CCP_OPEN) && (temp_i & SC_CCP_OPEN) == 0) ppp_ccp_closed (ppp); if ((ppp->flags | temp_i) & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: set flags to %x\n", temp_i); ppp->flags = temp_i; } break; /* * Set the compression mode */ case PPPIOCSCOMPRESS: error = ppp_set_compression (ppp, (struct ppp_option_data *) param3); break; /* * Retrieve the transmit async map */ case PPPIOCGASYNCMAP: error = verify_area (VERIFY_WRITE, (void *) param3, sizeof (temp_i)); if (error == 0) { put_user (ppp->xmit_async_map[0], (int *) param3); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: get asyncmap: addr " "%lx asyncmap %x\n", param3, ppp->xmit_async_map[0]); } break; /* * Set the transmit async map */ case PPPIOCSASYNCMAP: error = verify_area (VERIFY_READ, (void *) param3, sizeof (temp_i)); if (error == 0) { ppp->xmit_async_map[0] = get_user ((int *) param3); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: set xmit asyncmap %x\n", ppp->xmit_async_map[0]); } break; /* * Set the receive async map */ case PPPIOCSRASYNCMAP: error = verify_area (VERIFY_READ, (void *) param3, sizeof (temp_i)); if (error == 0) { ppp->recv_async_map = get_user ((int *) param3); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: set rcv asyncmap %x\n", ppp->recv_async_map); } break; /* * Obtain the unit number for this device. */ case PPPIOCGUNIT: error = verify_area (VERIFY_WRITE, (void *) param3, sizeof (temp_i)); if (error == 0) { put_user (ppp2dev (ppp)->base_addr, (int *) param3); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: get unit: %ld", ppp2dev (ppp)->base_addr); } break; /* * Set the debug level */ case PPPIOCSDEBUG: error = verify_area (VERIFY_READ, (void *) param3, sizeof (temp_i)); if (error == 0) { temp_i = (get_user ((int *) param3) & 0x1F) << 16; temp_i |= (ppp->flags & ~0x1F0000); if ((ppp->flags | temp_i) & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: set flags to %x\n", temp_i); ppp->flags = temp_i; } break; /* * Get the debug level */ case PPPIOCGDEBUG: error = verify_area (VERIFY_WRITE, (void *) param3, sizeof (temp_i)); if (error == 0) { temp_i = (ppp->flags >> 16) & 0x1F; put_user (temp_i, (int *) param3); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: get debug level %d\n", temp_i); } break; /* * Get the times since the last send/receive frame operation */ case PPPIOCGIDLE: error = verify_area (VERIFY_WRITE, (void *) param3, sizeof (struct ppp_idle)); if (error == 0) { struct ppp_idle cur_ddinfo; __u32 cur_jiffies = jiffies; /* change absolute times to relative times. */ cur_ddinfo.xmit_idle = (cur_jiffies - ppp->ddinfo.xmit_idle) / HZ; cur_ddinfo.recv_idle = (cur_jiffies - ppp->ddinfo.recv_idle) / HZ; memcpy_tofs ((void *) param3, &cur_ddinfo, sizeof (cur_ddinfo)); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: read demand dial info\n"); } break; /* * Retrieve the extended async map */ case PPPIOCGXASYNCMAP: error = verify_area (VERIFY_WRITE, (void *) param3, sizeof (ppp->xmit_async_map)); if (error == 0) { memcpy_tofs ((void *) param3, ppp->xmit_async_map, sizeof (ppp->xmit_async_map)); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: get xasyncmap: addr %lx\n", param3); } break; /* * Set the async extended map */ case PPPIOCSXASYNCMAP: error = verify_area (VERIFY_READ, (void *) param3, sizeof (ppp->xmit_async_map)); if (error == 0) { __u32 temp_tbl[8]; memcpy_fromfs (temp_tbl, (void *) param3, sizeof (ppp->xmit_async_map)); temp_tbl[1] = 0x00000000; temp_tbl[2] &= ~0x40000000; temp_tbl[3] |= 0x60000000; if ((temp_tbl[2] & temp_tbl[3]) != 0 || (temp_tbl[4] & temp_tbl[5]) != 0 || (temp_tbl[6] & temp_tbl[7]) != 0) error = -EINVAL; else { memcpy (ppp->xmit_async_map, temp_tbl, sizeof (ppp->xmit_async_map)); if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: set xasyncmap\n"); } } break; /* * Set the maximum VJ header compression slot number. */ case PPPIOCSMAXCID: error = verify_area (VERIFY_READ, (void *) param3, sizeof (temp_i)); if (error == 0) { temp_i = get_user ((int *) param3) + 1; if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_tty_ioctl: set maxcid to %d\n", temp_i); if (ppp->slcomp != NULL) slhc_free (ppp->slcomp); ppp->slcomp = slhc_init (16, temp_i); if (ppp->slcomp == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp: no space for compression buffers!\n"); ppp_release (ppp); error = -ENOMEM; } } break; case PPPIOCXFERUNIT: ppp_tty_close_local (tty, current->pid); break; case PPPIOCGNPMODE: case PPPIOCSNPMODE: error = verify_area (VERIFY_READ, (void *) param3, sizeof (struct npioctl)); if (error == 0) { struct npioctl npi; memcpy_fromfs (&npi, (void *) param3, sizeof (npi)); switch (npi.protocol) { case PPP_IP: npi.protocol = NP_IP; break; default: error = -EINVAL; } if (error != 0) break; if (param2 == PPPIOCGNPMODE) { npi.mode = ppp->sc_npmode[npi.protocol]; error = verify_area (VERIFY_WRITE, (void *) param3, sizeof (npi)); if (error != 0) break; memcpy_tofs ((void *) param3, &npi, sizeof (npi)); break; } if (npi.mode != ppp->sc_npmode[npi.protocol]) { ppp->sc_npmode[npi.protocol] = npi.mode; if (npi.mode != NPMODE_QUEUE) { /* ppp_requeue(ppp); maybe needed */ ppp_tty_wakeup (ppp2tty(ppp)); } } } break; /* * Allow users to read, but not set, the serial port parameters */ case TCGETS: case TCGETA: error = n_tty_ioctl (tty, file, param2, param3); break; case FIONREAD: error = verify_area (VERIFY_WRITE, (void *) param3, sizeof (int)); if (error == 0) { int count = ppp->ubuf->tail - ppp->ubuf->head; if (count < 0) count += (ppp->ubuf->size + 1); put_user (count, (int *) param3); } break; /* * All other ioctl() events will come here. */ default: if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_tty_ioctl: invalid ioctl: %x, addr %lx\n", param2, param3); error = -ENOIOCTLCMD; break; } return error; } /* * TTY callback. * * Process the select() statement for the PPP device. */ static int ppp_tty_select (struct tty_struct *tty, struct inode *inode, struct file *filp, int sel_type, select_table * wait) { struct ppp *ppp = tty2ppp (tty); int result = 1; /* * Verify the status of the PPP device. */ if (!ppp) return -EBADF; if (ppp->magic != PPP_MAGIC) return -EBADF; CHECK_PPP (0); /* * Branch on the type of select mode. A read request must lock the user * buffer area. */ switch (sel_type) { case SEL_IN: if (set_bit (0, &ppp->ubuf->locked) == 0) { /* Test for the presence of data in the queue */ if (ppp->ubuf->head != ppp->ubuf->tail) { clear_bit (0, &ppp->ubuf->locked); break; } clear_bit (0, &ppp->ubuf->locked); } /* fall through */ /* * Exceptions or read errors. */ case SEL_EX: /* Is this a pty link and the remote disconnected? */ if (tty->flags & (1 << TTY_OTHER_CLOSED)) break; /* Is this a local link and the modem disconnected? */ if (tty_hung_up_p (filp)) break; select_wait (&ppp->read_wait, wait); result = 0; break; /* * Write mode. A write is allowed if there is no current transmission. */ case SEL_OUT: if (ppp->tbuf->locked != 0) { select_wait (&ppp->write_wait, wait); result = 0; } break; } return result; } /************************************************************* * NETWORK OUTPUT * This routine accepts requests from the network layer * and attempts to deliver the packets. * It also includes various routines we are compelled to * have to make the network layer work (arp, etc...). *************************************************************/ /* * Callback from the network layer when the device goes up. */ static int ppp_dev_open (struct device *dev) { struct ppp *ppp = dev2ppp (dev); /* reset POINTOPOINT every time, since dev_close zaps it! */ dev->flags |= IFF_POINTOPOINT; if (ppp2tty (ppp) == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp: %s not connected to a TTY! can't go open!\n", dev->name); return -ENXIO; } if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp: channel %s going up for IP packets!\n", dev->name); CHECK_PPP (-ENXIO); return 0; } /* * Callback from the network layer when the ppp device goes down. */ static int ppp_dev_close (struct device *dev) { struct ppp *ppp = dev2ppp (dev); if (ppp2tty (ppp) == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp: %s not connected to a TTY! can't go down!\n", dev->name); return -ENXIO; } /* * We don't do anything about the device going down. It is not important * for us. */ if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp: channel %s going down for IP packets!\n", dev->name); CHECK_PPP (-ENXIO); return 0; } /* * IOCTL operation to read the version of the driver. */ static int ppp_dev_ioctl_version (struct ppp *ppp, struct ifreq *ifr) { int error; int len; char *result; /* * Must have write access to the buffer. */ result = (char *) ifr->ifr_ifru.ifru_data; len = strlen (szVersion) + 1; error = verify_area (VERIFY_WRITE, result, len); /* * Move the version data */ if (error == 0) memcpy_tofs (result, szVersion, len); return error; } /* * IOCTL to read the statistics for the pppstats program. */ static int ppp_dev_ioctl_stats (struct ppp *ppp, struct ifreq *ifr, struct device *dev) { struct ppp_stats *result, temp; int error; /* * Must have write access to the buffer. */ result = (struct ppp_stats *) ifr->ifr_ifru.ifru_data; error = verify_area (VERIFY_WRITE, result, sizeof (temp)); /* * Supply the information for the caller. First move the version data * then move the ppp stats; and finally the vj stats. */ memset (&temp, 0, sizeof(temp)); if (error == 0 && dev->flags & IFF_UP) { memcpy (&temp.p, &ppp->stats, sizeof (struct pppstat)); if (ppp->slcomp != NULL) { temp.vj.vjs_packets = ppp->slcomp->sls_o_compressed+ ppp->slcomp->sls_o_uncompressed; temp.vj.vjs_compressed = ppp->slcomp->sls_o_compressed; temp.vj.vjs_searches = ppp->slcomp->sls_o_searches; temp.vj.vjs_misses = ppp->slcomp->sls_o_misses; temp.vj.vjs_errorin = ppp->slcomp->sls_i_error; temp.vj.vjs_tossed = ppp->slcomp->sls_i_tossed; temp.vj.vjs_uncompressedin = ppp->slcomp->sls_i_uncompressed; temp.vj.vjs_compressedin = ppp->slcomp->sls_i_compressed; } } if (error == 0) memcpy_tofs (result, &temp, sizeof (temp)); return error; } /* * IOCTL to read the compression statistics for the pppstats program. */ static int ppp_dev_ioctl_comp_stats (struct ppp *ppp, struct ifreq *ifr, struct device *dev) { struct ppp_comp_stats *result, temp; int error; /* * Must have write access to the buffer. */ result = (struct ppp_comp_stats *) ifr->ifr_ifru.ifru_data; error = verify_area (VERIFY_WRITE, result, sizeof (temp)); /* * Supply the information for the caller. */ memset (&temp, 0, sizeof(temp)); if (error == 0 && dev->flags & IFF_UP) { if (ppp->sc_xc_state != NULL) (*ppp->sc_xcomp->comp_stat) (ppp->sc_xc_state, &temp.c); if (ppp->sc_rc_state != NULL) (*ppp->sc_rcomp->decomp_stat) (ppp->sc_rc_state, &temp.d); } /* * Move the data to the caller's buffer */ if (error == 0) memcpy_tofs (result, &temp, sizeof (temp)); return error; } /* * Callback from the network layer to process the sockioctl functions. */ static int ppp_dev_ioctl (struct device *dev, struct ifreq *ifr, int cmd) { struct ppp *ppp = dev2ppp (dev); int error; /* * Process the requests */ switch (cmd) { case SIOCGPPPSTATS: error = ppp_dev_ioctl_stats (ppp, ifr, dev); break; case SIOCGPPPCSTATS: error = ppp_dev_ioctl_comp_stats (ppp, ifr, dev); break; case SIOCGPPPVER: error = ppp_dev_ioctl_version (ppp, ifr); break; default: error = -EINVAL; break; } return error; } /* * Send an IP frame to the remote with vj header compression. * * Return 0 if frame was queued for transmission. * 1 if frame must be re-queued for later driver support. */ static int ppp_dev_xmit_ip (struct device *dev, struct ppp *ppp, __u8 *data) { int proto = PPP_IP; int len; struct ppp_hdr *hdr; struct tty_struct *tty = ppp2tty (ppp); /* * Obtain the length from the IP header. */ len = ((struct iphdr *)data) -> tot_len; len = ntohs (len); /* * Validate the tty interface */ if (tty == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_dev_xmit: %s not connected to a TTY!\n", dev->name); return 0; } /* * Ensure that the PPP device is still up */ if (!(dev->flags & IFF_UP)) { if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp_dev_xmit: packet sent on interface %s," " which is down for IP\n", dev->name); return 0; } /* * Branch on the type of processing for the IP frame. */ switch (ppp->sc_npmode[NP_IP]) { case NPMODE_PASS: break; case NPMODE_ERROR: if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp_dev_xmit: npmode = NPMODE_ERROR on %s\n", dev->name); return 0; case NPMODE_DROP: if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp_dev_xmit: npmode = NPMODE_DROP on %s\n", dev->name); return 0; case NPMODE_QUEUE: break; default: if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp_dev_xmit: unknown npmode %d on %s\n", ppp->sc_npmode[NP_IP], dev->name); return 0; } /* * Detect a change in the transfer size */ if (ppp->mtu != ppp2dev (ppp)->mtu) { ppp_changedmtu (ppp, ppp2dev (ppp)->mtu, ppp->mru); } /* * Acquire the lock on the transmission buffer. If the buffer was busy then * mark the device as busy. */ if (lock_buffer (ppp->wbuf) != 0) { dev->tbusy = 1; return 1; } /* * Print the frame being sent */ if (ppp->flags & SC_LOG_OUTPKT) ppp_print_buffer ("ppp outpkt", data, len); /* * At this point, the buffer will be transmitted. There is no other exit. * * Try to compress the header. */ if (ppp->flags & SC_COMP_TCP) { len = slhc_compress (ppp->slcomp, data, len, buf_base (ppp->cbuf) + PPP_HARD_HDR_LEN, &data, (ppp->flags & SC_NO_TCP_CCID) == 0); if (data[0] & SL_TYPE_COMPRESSED_TCP) { proto = PPP_VJC_COMP; data[0] ^= SL_TYPE_COMPRESSED_TCP; } else { if (data[0] >= SL_TYPE_UNCOMPRESSED_TCP) proto = PPP_VJC_UNCOMP; data[0] = (data[0] & 0x0f) | 0x40; } } /* * Send the frame */ len += PPP_HARD_HDR_LEN; hdr = &((struct ppp_hdr *) data)[-1]; hdr->address = PPP_ALLSTATIONS; hdr->control = PPP_UI; hdr->protocol[0] = 0; hdr->protocol[1] = proto; return ppp_dev_xmit_frame (ppp, ppp->wbuf, (__u8 *) hdr, len); } /* * Send an IPX (or any other non-IP) frame to the remote. * * Return 0 if frame was queued for transmission. * 1 if frame must be re-queued for later driver support. */ static int ppp_dev_xmit_ipx (struct device *dev, struct ppp *ppp, __u8 *data, int len, int proto) { struct tty_struct *tty = ppp2tty (ppp); struct ppp_hdr *hdr; /* * Validate the tty interface */ if (tty == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_dev_xmit: %s not connected to a TTY!\n", dev->name); return 0; } /* * Ensure that the PPP device is still up */ if (!(dev->flags & IFF_UP)) { if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp_dev_xmit: packet sent on interface %s," " which is down\n", dev->name); return 0; } /* * Detect a change in the transfer size */ if (ppp->mtu != ppp2dev (ppp)->mtu) { ppp_changedmtu (ppp, ppp2dev (ppp)->mtu, ppp->mru); } /* * Acquire the lock on the transmission buffer. If the buffer was busy then * mark the device as busy. */ if (lock_buffer (ppp->wbuf) != 0) { dev->tbusy = 1; return 1; } /* * Print the frame being sent */ if (ppp->flags & SC_LOG_OUTPKT) ppp_print_buffer ("ppp outpkt", data, len); /* * Send the frame */ len += PPP_HARD_HDR_LEN; hdr = &((struct ppp_hdr *) data)[-1]; hdr->address = PPP_ALLSTATIONS; hdr->control = PPP_UI; hdr->protocol[0] = proto >> 8; hdr->protocol[1] = proto; return ppp_dev_xmit_frame (ppp, ppp->wbuf, (__u8 *) hdr, len); } /* * Send a frame to the remote. */ static int ppp_dev_xmit (sk_buff *skb, struct device *dev) { int answer, len; __u8 *data; struct ppp *ppp = dev2ppp (dev); struct tty_struct *tty = ppp2tty (ppp); /* * just a little sanity check. */ if (skb == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_WARNING "ppp_dev_xmit: null packet!\n"); return 0; } /* * Avoid timing problem should tty hangup while data is queued to be sent */ if (!ppp->inuse) { dev_kfree_skb (skb, FREE_WRITE); dev_close (dev); return 0; } /* * Validate the tty linkage */ if (ppp->flags & SC_DEBUG) printk (KERN_DEBUG "ppp_dev_xmit [%s]: skb %p\n", dev->name, skb); /* * Validate the tty interface */ if (tty == NULL) { if (ppp->flags & SC_DEBUG) printk (KERN_ERR "ppp_dev_xmit: %s not connected to a TTY!\n", dev->name); dev_kfree_skb (skb, FREE_WRITE); return 0; } /* * Fetch the pointer to the data */ len = skb->len; data = skb_data(skb) + PPP_HARD_HDR_LEN; /* * Bug trap for null data. Release the skb and bail out. */ if(data == NULL) { printk("ppp_dev_xmit: data=NULL before ppp_dev_xmit_ip.\n"); dev_kfree_skb (skb, FREE_WRITE); return 0; } /* * Look at the protocol in the skb to determine the difference between * an IP frame and an IPX frame. */ switch (ntohs (skb->protocol)) { case ETH_P_IPX: answer = ppp_dev_xmit_ipx (dev, ppp, data, len, PPP_IPX); break; case ETH_P_IP: answer = ppp_dev_xmit_ip (dev, ppp, data); break; default: /* All others have no support at this time. */ dev_kfree_skb (skb, FREE_WRITE); return 0; } /* * This is the end of the transmission. Release the buffer if it was sent. */ if (answer == 0) { dev_kfree_skb (skb, FREE_WRITE); ppp->ddinfo.xmit_idle = jiffies; } return answer; } /* * Generate the statistic information for the /proc/net/dev listing. */ static struct enet_statistics * ppp_dev_stats (struct device *dev) { struct ppp *ppp = dev2ppp (dev); static struct enet_statistics ppp_stats; ppp_stats.rx_packets = ppp->stats.ppp_ipackets; ppp_stats.rx_errors = ppp->stats.ppp_ierrors; ppp_stats.rx_dropped = ppp->stats.ppp_ierrors; ppp_stats.rx_fifo_errors = 0; ppp_stats.rx_length_errors = 0; ppp_stats.rx_over_errors = 0; ppp_stats.rx_crc_errors = 0; ppp_stats.rx_frame_errors = 0; ppp_stats.tx_packets = ppp->stats.ppp_opackets; ppp_stats.tx_errors = ppp->stats.ppp_oerrors; ppp_stats.tx_dropped = 0; ppp_stats.tx_fifo_errors = 0; ppp_stats.collisions = 0; ppp_stats.tx_carrier_errors = 0; ppp_stats.tx_aborted_errors = 0; ppp_stats.tx_window_errors = 0; ppp_stats.tx_heartbeat_errors = 0; if (ppp->flags & SC_DEBUG) printk (KERN_INFO "ppp_dev_stats called"); return &ppp_stats; } static int ppp_dev_header (sk_buff *skb, struct device *dev, __u16 type, void *daddr, void *saddr, unsigned int len) { /* On the PPP device the hard header must be ignored * by the SOCK_PACKET layer. (Backward compatability). */ skb->mac.raw = skb->data; skb_push(skb,PPP_HARD_HDR_LEN); return PPP_HARD_HDR_LEN; } static int ppp_dev_rebuild (void *eth, struct device *dev, unsigned long raddr, struct sk_buff *skb) { return (0); } /************************************************************* * UTILITIES * Miscellany called by various functions above. *************************************************************/ /* Locate the previous instance of the PPP channel */ static struct ppp * ppp_find (int pid_value) { int if_num; ppp_ctrl_t *ctl; struct ppp *ppp; /* try to find the exact same free device which we had before */ ctl = ppp_list; if_num = 0; while (ctl) { ppp = ctl2ppp (ctl); if (!set_bit(0, &ppp->inuse)) { if (ppp->sc_xfer == pid_value) { ppp->sc_xfer = 0; return (ppp); } clear_bit (0, &ppp->inuse); } ctl = ctl->next; if (++if_num == max_dev) break; } return NULL; } /* allocate or create a PPP channel */ static struct ppp * ppp_alloc (void) { int if_num; int status; ppp_ctrl_t *ctl; struct device *dev; struct ppp *ppp; /* try to find an free device */ ctl = ppp_list; if_num = 0; while (ctl) { ppp = ctl2ppp (ctl); if (!set_bit(0, &ppp->inuse)) return (ppp); ctl = ctl->next; if (++if_num == max_dev) return (NULL); } /* * There are no available items. Allocate a device from the system pool */ ctl = (ppp_ctrl_t *) kmalloc (sizeof(ppp_ctrl_t), GFP_KERNEL); if (ctl) { (void) memset(ctl, 0, sizeof(ppp_ctrl_t)); ppp = ctl2ppp (ctl); dev = ctl2dev (ctl); /* initialize channel control data */ set_bit(0, &ppp->inuse); ppp->line = if_num; ppp->tty = NULL; ppp->dev = dev; dev->next = NULL; dev->init = ppp_init_dev; dev->name = ctl->name; dev->base_addr = (__u32) if_num; dev->priv = (void *) ppp; sprintf (dev->name, "ppp%d", if_num); /* link in the new channel */ ctl->next = ppp_list; ppp_list = ctl; /* register device so that we can be ifconfig'd */ /* ppp_init_dev() will be called as a side-effect */ status = register_netdev (dev); if (status == 0) { printk (KERN_INFO "registered device %s\n", dev->name); return (ppp); } printk (KERN_ERR "ppp_alloc - register_netdev(%s) = %d failure.\n", dev->name, status); /* This one will forever be busy as it is not initialized */ } return (NULL); } /* * Utility procedures to print a buffer in hex/ascii */ static void ppp_print_hex (register __u8 * out, const __u8 * in, int count) { register __u8 next_ch; static char hex[] = "0123456789ABCDEF"; while (count-- > 0) { next_ch = *in++; *out++ = hex[(next_ch >> 4) & 0x0F]; *out++ = hex[next_ch & 0x0F]; ++out; } } static void ppp_print_char (register __u8 * out, const __u8 * in, int count) { register __u8 next_ch; while (count-- > 0) { next_ch = *in++; if (next_ch < 0x20 || next_ch > 0x7e) *out++ = '.'; else { *out++ = next_ch; if (next_ch == '%') /* printk/syslogd has a bug !! */ *out++ = '%'; } } *out = '\0'; } static void ppp_print_buffer (const __u8 * name, const __u8 * buf, int count) { __u8 line[44]; if (name != (__u8 *) NULL) printk (KERN_DEBUG "ppp: %s, count = %d\n", name, count); while (count > 8) { memset (line, 32, 44); ppp_print_hex (line, buf, 8); ppp_print_char (&line[8 * 3], buf, 8); printk (KERN_DEBUG "%s\n", line); count -= 8; buf += 8; } if (count > 0) { memset (line, 32, 44); ppp_print_hex (line, buf, count); ppp_print_char (&line[8 * 3], buf, count); printk (KERN_DEBUG "%s\n", line); } } /************************************************************* * Compressor module interface *************************************************************/ struct compressor_link { struct compressor_link *next; struct compressor *comp; }; static struct compressor_link *ppp_compressors = (struct compressor_link *) 0; static struct compressor *find_compressor (int type) { struct compressor_link *lnk; __u32 flags; save_flags(flags); cli(); lnk = ppp_compressors; while (lnk != (struct compressor_link *) 0) { if ((int) (__u8) lnk->comp->compress_proto == type) { restore_flags(flags); return lnk->comp; } lnk = lnk->next; } restore_flags(flags); return (struct compressor *) 0; } static int ppp_register_compressor (struct compressor *cp) { struct compressor_link *new; __u32 flags; new = (struct compressor_link *) kmalloc (sizeof (struct compressor_link), GFP_KERNEL); if (new == (struct compressor_link *) 0) return 1; save_flags(flags); cli(); if (find_compressor (cp->compress_proto)) { restore_flags(flags); kfree (new); return 0; } new->next = ppp_compressors; new->comp = cp; ppp_compressors = new; restore_flags(flags); return 0; } static void ppp_unregister_compressor (struct compressor *cp) { struct compressor_link *prev = (struct compressor_link *) 0; struct compressor_link *lnk; __u32 flags; save_flags(flags); cli(); lnk = ppp_compressors; while (lnk != (struct compressor_link *) 0) { if (lnk->comp == cp) { if (prev) prev->next = lnk->next; else ppp_compressors = lnk->next; kfree (lnk); break; } prev = lnk; lnk = lnk->next; } restore_flags(flags); } /************************************************************* * Module support routines *************************************************************/ #ifdef MODULE int init_module(void) { int status; /* register our line disciplines */ status = ppp_first_time(); if (status != 0) printk (KERN_INFO "PPP: ppp_init() failure %d\n", status); else (void) register_symtab (&ppp_syms); return (status); } void cleanup_module(void) { int status; ppp_ctrl_t *ctl, *next_ctl; struct device *dev; struct ppp *ppp; int busy_flag = 0; /* * Ensure that the devices are not in operation. */ ctl = ppp_list; while (ctl) { ppp = ctl2ppp (ctl); if (ppp->inuse && ppp->tty != NULL) { busy_flag = 1; break; } dev = ctl2dev (ctl); if (dev->start || dev->flags & IFF_UP) { busy_flag = 1; break; } ctl = ctl->next; } /* * Ensure that there are no compressor modules registered */ if (ppp_compressors != NULL) busy_flag = 1; if (busy_flag) { printk (KERN_INFO "PPP: device busy, remove delayed\n"); return; } /* * Release the tty registration of the line discipline so that no new entries * may be created. */ status = tty_register_ldisc (N_PPP, NULL); if (status != 0) printk (KERN_INFO "PPP: Unable to unregister ppp line discipline " "(err = %d)\n", status); else printk (KERN_INFO "PPP: ppp line discipline successfully unregistered\n"); /* * De-register the devices so that there is no problem with them */ next_ctl = ppp_list; while (next_ctl) { ctl = next_ctl; next_ctl = ctl->next; ppp = ctl2ppp (ctl); dev = ctl2dev (ctl); ppp_release (ppp); unregister_netdev (dev); kfree (ctl); } } #endif