isdn_common.c

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/* $Id: isdn_common.c,v 1.114 2000/11/25 17:00:59 kai Exp $

 * Linux ISDN subsystem, common used functions (linklevel).
 *
 * Copyright 1994-1999  by Fritz Elfert ([e-mail])
 * Copyright 1995,96    Thinking Objects Software GmbH Wuerzburg
 * Copyright 1995,96    by Michael Hipp ([e-mail])
 *
 * 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, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/version.h>
#include <linux/poll.h>
#include <linux/vmalloc.h>
#include <linux/isdn.h>
#include <linux/smp_lock.h>
#include "isdn_common.h"
#include "isdn_tty.h"
#include "isdn_net.h"
#include "isdn_ppp.h"
#ifdef CONFIG_ISDN_AUDIO
#include "isdn_audio.h"
#endif
#ifdef CONFIG_ISDN_DIVERSION_MODULE
#define CONFIG_ISDN_DIVERSION
#endif
#ifdef CONFIG_ISDN_DIVERSION
#include <linux/isdn_divertif.h>
#endif CONFIG_ISDN_DIVERSION
#include "isdn_v110.h"
#include "isdn_cards.h"
#include <linux/devfs_fs_kernel.h>

/* Debugflags */
#undef ISDN_DEBUG_STATCALLB

isdn_dev *dev;

static char *isdn_revision = "$Revision: 1.114 $";

extern char *isdn_net_revision;
extern char *isdn_tty_revision;
#ifdef CONFIG_ISDN_PPP
extern char *isdn_ppp_revision;
#else
static char *isdn_ppp_revision = ": none $";
#endif
#ifdef CONFIG_ISDN_AUDIO
extern char *isdn_audio_revision;
#else
static char *isdn_audio_revision = ": none $";
#endif
extern char *isdn_v110_revision;

#ifdef CONFIG_ISDN_DIVERSION
static isdn_divert_if *divert_if; /* = NULL */
#endif CONFIG_ISDN_DIVERSION


static int isdn_writebuf_stub(int, int, const u_char *, int, int);
static void set_global_features(void);
static void isdn_register_devfs(int);
static void isdn_unregister_devfs(int);
static int isdn_wildmat(char *s, char *p);

void
isdn_lock_drivers(void)
{
	int i;

	for (i = 0; i < dev->drivers; i++) {
		isdn_ctrl cmd;

		cmd.driver = i;
		cmd.arg = 0;
		cmd.command = ISDN_CMD_LOCK;
		isdn_command(&cmd);
		dev->drv[i]->locks++;
	}
}

void
isdn_MOD_INC_USE_COUNT(void)
{
	MOD_INC_USE_COUNT;
	isdn_lock_drivers();
}

void
isdn_unlock_drivers(void)
{
	int i;

	for (i = 0; i < dev->drivers; i++)
		if (dev->drv[i]->locks > 0) {
			isdn_ctrl cmd;

			cmd.driver = i;
			cmd.arg = 0;
			cmd.command = ISDN_CMD_UNLOCK;
			isdn_command(&cmd);
			dev->drv[i]->locks--;
		}
}

void
isdn_MOD_DEC_USE_COUNT(void)
{
	MOD_DEC_USE_COUNT;
	isdn_unlock_drivers();
}

#if defined(ISDN_DEBUG_NET_DUMP) || defined(ISDN_DEBUG_MODEM_DUMP)
void
isdn_dumppkt(char *s, u_char * p, int len, int dumplen)
{
	int dumpc;

	printk(KERN_DEBUG "%s(%d) ", s, len);
	for (dumpc = 0; (dumpc < dumplen) && (len); len--, dumpc++)
		printk(" %02x", *p++);
	printk("\n");
}
#endif

/*
 * I picked the pattern-matching-functions from an old GNU-tar version (1.10)
 * It was originally written and put to PD by [e-mail] (Rich Salz)
 */
static int
isdn_star(char *s, char *p)
{
	while (isdn_wildmat(s, p)) {
		if (*++s == '\0')
			return (2);
	}
	return (0);
}

/*
 * Shell-type Pattern-matching for incoming caller-Ids
 * This function gets a string in s and checks, if it matches the pattern
 * given in p.
 *
 * Return:
 *   0 = match.
 *   1 = no match.
 *   2 = no match. Would eventually match, if s would be longer.
 *
 * Possible Patterns:
 *
 * '?'     matches one character
 * '*'     matches zero or more characters
 * [xyz]   matches the set of characters in brackets.
 * [^xyz]  matches any single character not in the set of characters
 */

static int
isdn_wildmat(char *s, char *p)
{
	register int last;
	register int matched;
	register int reverse;
	register int nostar = 1;

	if (!(*s) && !(*p))
		return(1);
	for (; *p; s++, p++)
		switch (*p) {
			case '\\':
				/*
				 * Literal match with following character,
				 * fall through.
				 */
				p++;
			default:
				if (*s != *p)
					return (*s == '\0')?2:1;
				continue;
			case '?':
				/* Match anything. */
				if (*s == '\0')
					return (2);
				continue;
			case '*':
				nostar = 0;	
				/* Trailing star matches everything. */
				return (*++p ? isdn_star(s, p) : 0);
			case '[':
				/* [^....] means inverse character class. */
				if ((reverse = (p[1] == '^')))
					p++;
				for (last = 0, matched = 0; *++p && (*p != ']'); last = *p)
					/* This next line requires a good C compiler. */
					if (*p == '-' ? *s <= *++p && *s >= last : *s == *p)
						matched = 1;
				if (matched == reverse)
					return (1);
				continue;
		}
	return (*s == '\0')?0:nostar;
}

int isdn_msncmp( const char * msn1, const char * msn2 )
{
	char TmpMsn1[ ISDN_MSNLEN ];
	char TmpMsn2[ ISDN_MSNLEN ];
	char *p;

	for ( p = TmpMsn1; *msn1 && *msn1 != ':'; )  // Strip off a SPID
		*p++ = *msn1++;
	*p = '\0';

	for ( p = TmpMsn2; *msn2 && *msn2 != ':'; )  // Strip off a SPID
		*p++ = *msn2++;
	*p = '\0';

	return isdn_wildmat( TmpMsn1, TmpMsn2 );
}

static void
isdn_free_queue(struct sk_buff_head *queue)
{
	struct sk_buff *skb;
	unsigned long flags;

	save_flags(flags);
	cli();
	if (skb_queue_len(queue))
		while ((skb = skb_dequeue(queue)))
			dev_kfree_skb(skb);
	restore_flags(flags);
}

int
isdn_dc2minor(int di, int ch)
{
	int i;
	for (i = 0; i < ISDN_MAX_CHANNELS; i++)
		if (dev->chanmap[i] == ch && dev->drvmap[i] == di)
			return i;
	return -1;
}

static int isdn_timer_cnt1 = 0;
static int isdn_timer_cnt2 = 0;
static int isdn_timer_cnt3 = 0;
static int isdn_timer_cnt4 = 0;

static void
isdn_timer_funct(ulong dummy)
{
	int tf = dev->tflags;
	if (tf & ISDN_TIMER_FAST) {
		if (tf & ISDN_TIMER_MODEMREAD)
			isdn_tty_readmodem();
		if (tf & ISDN_TIMER_MODEMPLUS)
			isdn_tty_modem_escape();
		if (tf & ISDN_TIMER_MODEMXMIT)
			isdn_tty_modem_xmit();
	}
	if (tf & ISDN_TIMER_SLOW) {
		if (++isdn_timer_cnt1 >= ISDN_TIMER_02SEC) {
			isdn_timer_cnt1 = 0;
			if (tf & ISDN_TIMER_NETDIAL)
				isdn_net_dial();
		}
		if (++isdn_timer_cnt2 >= ISDN_TIMER_1SEC) {
			isdn_timer_cnt2 = 0;
			if (tf & ISDN_TIMER_NETHANGUP)
				isdn_net_autohup();
			if (++isdn_timer_cnt3 > ISDN_TIMER_RINGING) {
				isdn_timer_cnt3 = 0;
				if (tf & ISDN_TIMER_MODEMRING)
					isdn_tty_modem_ring();
			}
			if (++isdn_timer_cnt4 > ISDN_TIMER_KEEPINT) {
				isdn_timer_cnt4 = 0;
				if (tf & ISDN_TIMER_KEEPALIVE)
					isdn_net_slarp_out();
			}
			if (tf & ISDN_TIMER_CARRIER)
				isdn_tty_carrier_timeout();
		}
	}
	if (tf) 
	{
		int flags;

		save_flags(flags);
		cli();
		mod_timer(&dev->timer, jiffies+ISDN_TIMER_RES);
		restore_flags(flags);
	}
}

void
isdn_timer_ctrl(int tf, int onoff)
{
	int flags;

	save_flags(flags);
	cli();
	if ((tf & ISDN_TIMER_SLOW) && (!(dev->tflags & ISDN_TIMER_SLOW))) {
		/* If the slow-timer wasn't activated until now */
		isdn_timer_cnt1 = 0;
		isdn_timer_cnt2 = 0;
	}
	if (onoff)
		dev->tflags |= tf;
	else
		dev->tflags &= ~tf;
	if (dev->tflags)
		mod_timer(&dev->timer, jiffies+ISDN_TIMER_RES);
	restore_flags(flags);
}

/*
 * Receive a packet from B-Channel. (Called from low-level-module)
 */
static void
isdn_receive_skb_callback(int di, int channel, struct sk_buff *skb)
{
	int i;

	if ((i = isdn_dc2minor(di, channel)) == -1) {
		dev_kfree_skb(skb);
		return;
	}
	/* Update statistics */
	dev->ibytes[i] += skb->len;
	
	/* First, try to deliver data to network-device */
	if (isdn_net_rcv_skb(i, skb))
		return;

	/* V.110 handling
	 * makes sense for async streams only, so it is
	 * called after possible net-device delivery.
	 */
	if (dev->v110[i]) {
		atomic_inc(&dev->v110use[i]);
		skb = isdn_v110_decode(dev->v110[i], skb);
		atomic_dec(&dev->v110use[i]);
		if (!skb)
			return;
	}

	/* No network-device found, deliver to tty or raw-channel */
	if (skb->len) {
		if (isdn_tty_rcv_skb(i, di, channel, skb))
			return;
		wake_up_interruptible(&dev->drv[di]->rcv_waitq[channel]);
	} else
		dev_kfree_skb(skb);
}

/*
 * Intercept command from Linklevel to Lowlevel.
 * If layer 2 protocol is V.110 and this is not supported by current
 * lowlevel-driver, use driver's transparent mode and handle V.110 in
 * linklevel instead.
 */
int
isdn_command(isdn_ctrl *cmd)
{
	if (cmd->driver == -1) {
		printk(KERN_WARNING "isdn_command command(%x) driver -1\n", cmd->command);
		return(1);
	}
	if (cmd->command == ISDN_CMD_SETL2) {
		int idx = isdn_dc2minor(cmd->driver, cmd->arg & 255);
		unsigned long l2prot = (cmd->arg >> 8) & 255;
		unsigned long features = (dev->drv[cmd->driver]->interface->features
						>> ISDN_FEATURE_L2_SHIFT) &
						ISDN_FEATURE_L2_MASK;
		unsigned long l2_feature = (1 << l2prot);

		switch (l2prot) {
			case ISDN_PROTO_L2_V11096:
			case ISDN_PROTO_L2_V11019:
			case ISDN_PROTO_L2_V11038:
			/* If V.110 requested, but not supported by
			 * HL-driver, set emulator-flag and change
			 * Layer-2 to transparent
			 */
				if (!(features & l2_feature)) {
					dev->v110emu[idx] = l2prot;
					cmd->arg = (cmd->arg & 255) |
						(ISDN_PROTO_L2_TRANS << 8);
				} else
					dev->v110emu[idx] = 0;
		}
	}
	return dev->drv[cmd->driver]->interface->command(cmd);
}

void
isdn_all_eaz(int di, int ch)
{
	isdn_ctrl cmd;

	if (di < 0)
		return;
	cmd.driver = di;
	cmd.arg = ch;
	cmd.command = ISDN_CMD_SETEAZ;
	cmd.parm.num[0] = '\0';
	isdn_command(&cmd);
}

/*
 * Begin of a CAPI like LL<->HL interface, currently used only for 
 * supplementary service (CAPI 2.0 part III)
 */
#include "avmb1/capicmd.h"  /* this should be moved in a common place */

int
isdn_capi_rec_hl_msg(capi_msg *cm) {
	
	int di;
	int ch;
	
	di = (cm->adr.Controller & 0x7f) -1;
	ch = isdn_dc2minor(di, (cm->adr.Controller>>8)& 0x7f);
	switch(cm->Command) {
		case CAPI_FACILITY:
			/* in the moment only handled in tty */
			return(isdn_tty_capi_facility(cm));
		default:
			return(-1);
	}
}

static int
isdn_status_callback(isdn_ctrl * c)
{
	int di;
	ulong flags;
	int i;
	int r;
	int retval = 0;
	isdn_ctrl cmd;
	isdn_net_dev *p;

	di = c->driver;
	i = isdn_dc2minor(di, c->arg);
	switch (c->command) {
		case ISDN_STAT_BSENT:
			if (i < 0)
				return -1;
			if (dev->global_flags & ISDN_GLOBAL_STOPPED)
				return 0;
			if (isdn_net_stat_callback(i, c))
				return 0;
			if (isdn_v110_stat_callback(i, c))
				return 0;
			if (isdn_tty_stat_callback(i, c))
				return 0;
			wake_up_interruptible(&dev->drv[di]->snd_waitq[c->arg]);
			break;
		case ISDN_STAT_STAVAIL:
			save_flags(flags);
			cli();
			dev->drv[di]->stavail += c->arg;
			restore_flags(flags);
			wake_up_interruptible(&dev->drv[di]->st_waitq);
			break;
		case ISDN_STAT_RUN:
			dev->drv[di]->flags |= DRV_FLAG_RUNNING;
			for (i = 0; i < ISDN_MAX_CHANNELS; i++)
				if (dev->drvmap[i] == di)
					isdn_all_eaz(di, dev->chanmap[i]);
			set_global_features();
			break;
		case ISDN_STAT_STOP:
			dev->drv[di]->flags &= ~DRV_FLAG_RUNNING;
			break;
		case ISDN_STAT_ICALL:
			if (i < 0)
				return -1;
#ifdef ISDN_DEBUG_STATCALLB
			printk(KERN_DEBUG "ICALL (net): %d %ld %s\n", di, c->arg, c->parm.num);
#endif
			if (dev->global_flags & ISDN_GLOBAL_STOPPED) {
				cmd.driver = di;
				cmd.arg = c->arg;
				cmd.command = ISDN_CMD_HANGUP;
				isdn_command(&cmd);
				return 0;
			}
			/* Try to find a network-interface which will accept incoming call */
			r = ((c->command == ISDN_STAT_ICALLW) ? 0 : isdn_net_find_icall(di, c->arg, i, &c->parm.setup));
			switch (r) {
				case 0:
					/* No network-device replies.
					 * Try ttyI's.
					 * These return 0 on no match, 1 on match and
					 * 3 on eventually match, if CID is longer.
					 */
                                        if (c->command == ISDN_STAT_ICALL)
					  if ((retval = isdn_tty_find_icall(di, c->arg, &c->parm.setup))) return(retval);
#ifdef CONFIG_ISDN_DIVERSION 
                                         if (divert_if)
                 	                  if ((retval = divert_if->stat_callback(c))) 
					    return(retval); /* processed */
#endif CONFIG_ISDN_DIVERSION                        
					if ((!retval) && (dev->drv[di]->flags & DRV_FLAG_REJBUS)) {
						/* No tty responding */
						cmd.driver = di;
						cmd.arg = c->arg;
						cmd.command = ISDN_CMD_HANGUP;
						isdn_command(&cmd);
						retval = 2;
					}
					break;
				case 1:
					/* Schedule connection-setup */
					isdn_net_dial();
					cmd.driver = di;
					cmd.arg = c->arg;
					cmd.command = ISDN_CMD_ACCEPTD;
					for ( p = dev->netdev; p; p = p->next )
						if ( p->local->isdn_channel == cmd.arg )
						{
							strcpy( cmd.parm.setup.eazmsn, p->local->msn );
							isdn_command(&cmd);
							retval = 1;
							break;
						}
					break;

				case 2:	/* For calling back, first reject incoming call ... */
				case 3:	/* Interface found, but down, reject call actively  */
					retval = 2;
					printk(KERN_INFO "isdn: Rejecting Call\n");
					cmd.driver = di;
					cmd.arg = c->arg;
					cmd.command = ISDN_CMD_HANGUP;
					isdn_command(&cmd);
					if (r == 3)
						break;
					/* Fall through */
				case 4:
					/* ... then start callback. */
					isdn_net_dial();
					break;
				case 5:
					/* Number would eventually match, if longer */
					retval = 3;
					break;
			}
#ifdef ISDN_DEBUG_STATCALLB
			printk(KERN_DEBUG "ICALL: ret=%d\n", retval);
#endif
			return retval;
			break;
		case ISDN_STAT_CINF:
			if (i < 0)
				return -1;
#ifdef ISDN_DEBUG_STATCALLB
			printk(KERN_DEBUG "CINF: %ld %s\n", c->arg, c->parm.num);
#endif
			if (dev->global_flags & ISDN_GLOBAL_STOPPED)
				return 0;
			if (strcmp(c->parm.num, "0"))
				isdn_net_stat_callback(i, c);
			isdn_tty_stat_callback(i, c);
			break;
		case ISDN_STAT_CAUSE:
#ifdef ISDN_DEBUG_STATCALLB
			printk(KERN_DEBUG "CAUSE: %ld %s\n", c->arg, c->parm.num);
#endif
			printk(KERN_INFO "isdn: %s,ch%ld cause: %s\n",
			       dev->drvid[di], c->arg, c->parm.num);
			isdn_tty_stat_callback(i, c);
#ifdef CONFIG_ISDN_DIVERSION
                        if (divert_if)
                         divert_if->stat_callback(c); 
#endif CONFIG_ISDN_DIVERSION
			break;
		case ISDN_STAT_DISPLAY:
#ifdef ISDN_DEBUG_STATCALLB
			printk(KERN_DEBUG "DISPLAY: %ld %s\n", c->arg, c->parm.display);
#endif
			isdn_tty_stat_callback(i, c);
#ifdef CONFIG_ISDN_DIVERSION
                        if (divert_if)
                         divert_if->stat_callback(c); 
#endif CONFIG_ISDN_DIVERSION
			break;
		case ISDN_STAT_DCONN:
			if (i < 0)
				return -1;
#ifdef ISDN_DEBUG_STATCALLB
			printk(KERN_DEBUG "DCONN: %ld\n", c->arg);
#endif
			if (dev->global_flags & ISDN_GLOBAL_STOPPED)
				return 0;
			/* Find any net-device, waiting for D-channel setup */
			if (isdn_net_stat_callback(i, c))
				break;
			isdn_v110_stat_callback(i, c);
			/* Find any ttyI, waiting for D-channel setup */
			if (isdn_tty_stat_callback(i, c)) {
				cmd.driver = di;