sdla_chdlc.c

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			printk(KERN_WARNING "  format A.B.C.1 or A.B.C.2.\n");
		}
		*/		
	}
	
	return chdlc_configure(card, &cfg);
}



/*============================================================================
 * Process global exception condition
 */
static int process_global_exception(sdla_t *card)
{
	CHDLC_MAILBOX_STRUCT* mbox = card->mbox;
	int err;

	mbox->buffer_length = 0;
	mbox->command = READ_GLOBAL_EXCEPTION_CONDITION;
	err = sdla_exec(mbox) ? mbox->return_code : CMD_TIMEOUT;

	if(err != CMD_TIMEOUT ){
	
		switch(mbox->return_code) {
         
	      	case EXCEP_MODEM_STATUS_CHANGE:

			printk(KERN_INFO "%s: Modem status change\n",
				card->devname);

			switch(mbox->data[0] & (DCD_HIGH | CTS_HIGH)) {
				case (DCD_HIGH):
					printk(KERN_INFO "%s: DCD high, CTS low\n",card->devname);
					break;
				case (CTS_HIGH):
                                        printk(KERN_INFO "%s: DCD low, CTS high\n",card->devname);                                        break;
                                case ((DCD_HIGH | CTS_HIGH)):
                                        printk(KERN_INFO "%s: DCD high, CTS high\n",card->devname);
                                        break;
				default:
                                        printk(KERN_INFO "%s: DCD low, CTS low\n",card->devname);
                                        break;
			}
			break;

                case EXCEP_TRC_DISABLED:
                        printk(KERN_INFO "%s: Line trace disabled\n",
				card->devname);
                        break;

		case EXCEP_IRQ_TIMEOUT:
			printk(KERN_INFO "%s: IRQ timeout occurred\n",
				card->devname); 
			break;

                default:
                        printk(KERN_INFO "%s: Global exception %x\n",
				card->devname, mbox->return_code);
                        break;
                }
	}
	return 0;
}


/*============================================================================
 * Process chdlc exception condition
 */
static int process_chdlc_exception(sdla_t *card)
{
	CHDLC_MAILBOX_STRUCT* mb = card->mbox;
	int err;

	mb->buffer_length = 0;
	mb->command = READ_CHDLC_EXCEPTION_CONDITION;
	err = sdla_exec(mb) ? mb->return_code : CMD_TIMEOUT;
	if(err != CMD_TIMEOUT) {
	
		switch (err) {

		case EXCEP_LINK_ACTIVE:
			port_set_state(card, WAN_CONNECTED);
			break;

		case EXCEP_LINK_INACTIVE_MODEM:
			port_set_state(card, WAN_DISCONNECTED);
			unconfigure_ip(card);
			break;

		case EXCEP_LINK_INACTIVE_KPALV:
			port_set_state(card, WAN_DISCONNECTED);
			printk(KERN_INFO "%s: Keepalive timer expired.\n",
				 		card->devname);
			unconfigure_ip(card);
			break;

		case EXCEP_IP_ADDRESS_DISCOVERED:
			if (configure_ip(card)) 
				return -1;
			break;

		case EXCEP_LOOPBACK_CONDITION:
			printk(KERN_INFO "%s: Loopback Condition Detected.\n",
						card->devname);
			break;

		case NO_CHDLC_EXCEP_COND_TO_REPORT:
			printk(KERN_INFO "%s: No exceptions reported.\n",
						card->devname);
			break;
		}

	}
	return 0;
}


/*============================================================================
 * Configure IP from SLARP negotiation
 * This adds dynamic routes when SLARP has provided valid addresses
 */

static int configure_ip (sdla_t* card)
{
	struct net_device *dev = card->wandev.dev;
        chdlc_private_area_t *chdlc_priv_area = dev->priv;
        char err;

        /* set to discover */
        if(card->u.c.slarp_timer != 0x00) {
		CHDLC_MAILBOX_STRUCT* mb = card->mbox;
		CHDLC_CONFIGURATION_STRUCT *cfg;

     		mb->buffer_length = 0;
		mb->command = READ_CHDLC_CONFIGURATION;
		err = sdla_exec(mb) ? mb->return_code : CMD_TIMEOUT;
	
		if(err != COMMAND_OK) {
			chdlc_error(card,err,mb);
			return -1;
		}

		cfg = (CHDLC_CONFIGURATION_STRUCT *)mb->data;
                chdlc_priv_area->IP_address = cfg->IP_address;
                chdlc_priv_area->IP_netmask = cfg->IP_netmask;
        }

	/* Set flag to add route */
	chdlc_priv_area->route_status = ADD_ROUTE;

	/* The idea here is to add the route in the poll routine.
	   This way, we aren't in interrupt context when adding routes */
	card->poll = process_route;

	return 0;
}


/*============================================================================
 * Un-Configure IP negotiated by SLARP
 * This removes dynamic routes when the link becomes inactive.
 */

static int unconfigure_ip (sdla_t* card)
{
	struct net_device *dev = card->wandev.dev;
	chdlc_private_area_t *chdlc_priv_area= dev->priv;

	if (chdlc_priv_area->route_status == ROUTE_ADDED) {
	      	chdlc_priv_area->route_status = REMOVE_ROUTE;
		/* The idea here is to delete the route in 
		 * the poll routine.
	   	 * This way, we aren't in interrupt context 
		 * when adding routes 
		 */
                card->poll = process_route;
	}
	return 0;
}

/*============================================================================
 * Routine to add/remove routes 
 * Called like a polling routine when Routes are flagged to be added/removed.
 */

static void process_route (sdla_t *card)
{
        struct net_device *dev = card->wandev.dev;
        unsigned char port_num;
        chdlc_private_area_t *chdlc_priv_area = NULL;
	u32 local_IP_addr = 0;
	u32 remote_IP_addr = 0;
	u32 IP_netmask, IP_addr;
        int err = 0;
#ifdef LINUX_2_1
	struct in_device *in_dev;
	mm_segment_t fs;
	struct ifreq if_info;
        struct sockaddr_in *if_data1, *if_data2;
#else
	unsigned long fs = 0;
        struct rtentry route;
#endif
	
        chdlc_priv_area = dev->priv;
        port_num = card->u.c.comm_port;

	if((chdlc_priv_area->route_status == ADD_ROUTE) &&
		((chdlc_priv_area->IP_address & 0x000000FF) > 2)) {
		printk(KERN_INFO "%s: Dynamic route failure.\n",card->devname);
                if(card->u.c.slarp_timer) {
			printk(KERN_INFO "%s: Bad IP address %s received\n",
				card->devname,
				in_ntoa(ntohl(chdlc_priv_area->IP_address)));
                        printk(KERN_INFO "%s: from remote station.\n",
				card->devname);
                }else{ 
                        printk(KERN_INFO "%s: Bad IP address %s issued\n",
				card->devname,
				in_ntoa(ntohl(chdlc_priv_area->IP_address)));
                        printk(KERN_INFO "%s: to remote station. Local\n",
				card->devname);
			printk(KERN_INFO "%s: IP address must be A.B.C.1\n",
				card->devname);
			printk(KERN_INFO "%s: or A.B.C.2.\n",card->devname);
		}

		/* remove the route due to the IP address error condition */
		chdlc_priv_area->route_status = REMOVE_ROUTE;
		err = 1;
   	}

	/* If we are removing a route with bad IP addressing, then use the */
	/* locally configured IP addresses */
        if((chdlc_priv_area->route_status == REMOVE_ROUTE) && err) {

 	        /* do not remove a bad route that has already been removed */
        	if(chdlc_priv_area->route_removed) {
                	card->poll = NULL;
	                return;
        	}

#ifdef LINUX_2_1
                in_dev = dev->ip_ptr;

                if(in_dev != NULL) {
                        struct in_ifaddr *ifa = in_dev->ifa_list;
                        if (ifa != NULL ) {
                                local_IP_addr = ifa->ifa_local;
                                IP_netmask  = ifa->ifa_mask;
                        }
                }
#else
                local_IP_addr = dev->pa_addr;
                remote_IP_addr = dev->pa_dstaddr;
                IP_netmask = dev->pa_mask;
#endif
	}else{ 
       		/* According to Cisco HDLC, if the point-to-point address is
		   A.B.C.1, then we are the opposite (A.B.C.2), and vice-versa.
		*/
		IP_netmask = ntohl(chdlc_priv_area->IP_netmask);
	        remote_IP_addr = ntohl(chdlc_priv_area->IP_address);
        	local_IP_addr = (remote_IP_addr & ntohl(0xFFFFFF00)) +
                	(~remote_IP_addr & ntohl(0x0003));

	        if(!card->u.c.slarp_timer) {
			IP_addr = local_IP_addr;
			local_IP_addr = remote_IP_addr;
			remote_IP_addr = IP_addr;
       		}
	}

        fs = get_fs();                  /* Save file system  */
        set_fs(get_ds());               /* Get user space block */

#ifdef LINUX_2_1
        /* Setup a structure for adding/removing routes */
        memset(&if_info, 0, sizeof(if_info));
        strcpy(if_info.ifr_name, dev->name);

#else
	/* Setup a structure for adding/removing routes */
	dev->pa_mask = IP_netmask;
	dev->pa_dstaddr = remote_IP_addr;
	dev->pa_addr = local_IP_addr;

	memset(&route, 0, sizeof(route));
	route.rt_dev = dev->name;
	route.rt_flags = 0;
	((struct sockaddr_in *)&(route.rt_dst))->sin_addr.s_addr =
			dev->pa_dstaddr;
	((struct sockaddr_in *)&(route.rt_dst))->sin_family = AF_INET;
	((struct sockaddr_in *)&(route.rt_genmask))->sin_addr.s_addr =
			0xFFFFFFFF;
        ((struct sockaddr_in *)&(route.rt_genmask))->sin_family =
			AF_INET;
#endif

	switch (chdlc_priv_area->route_status) {

	case ADD_ROUTE:

		if(!card->u.c.slarp_timer) {
#ifdef LINUX_2_1
			if_data2 = (struct sockaddr_in *)&if_info.ifr_dstaddr;
			if_data2->sin_addr.s_addr = remote_IP_addr;
			if_data2->sin_family = AF_INET;
			err = devinet_ioctl(SIOCSIFDSTADDR, &if_info);
#else
                        err = ip_rt_new(&route);
#endif
		} else { 
#ifdef LINUX_2_1
			if_data1 = (struct sockaddr_in *)&if_info.ifr_addr;
			if_data1->sin_addr.s_addr = local_IP_addr;
			if_data1->sin_family = AF_INET;
			if(!(err = devinet_ioctl(SIOCSIFADDR, &if_info))){
				if_data2 = (struct sockaddr_in *)&if_info.ifr_dstaddr;
				if_data2->sin_addr.s_addr = remote_IP_addr;
				if_data2->sin_family = AF_INET;
				err = devinet_ioctl(SIOCSIFDSTADDR, &if_info);
			}
#else
               		err = ip_rt_new(&route);
#endif
		}

               if(err) {
			printk(KERN_INFO "%s: Add route %s failed (%d)\n", 
				card->devname, in_ntoa(remote_IP_addr), err);
		} else {
			((chdlc_private_area_t *)dev->priv)->route_status = ROUTE_ADDED;
			printk(KERN_INFO "%s: Dynamic route added.\n",
				card->devname);
			printk(KERN_INFO "%s:    Local IP addr : %s\n",
				card->devname, in_ntoa(local_IP_addr));
			printk(KERN_INFO "%s:    Remote IP addr: %s\n",
				card->devname, in_ntoa(remote_IP_addr));
			chdlc_priv_area->route_removed = 0;
		}
		break;


	case REMOVE_ROUTE:
	
#ifdef LINUX_2_1
		/* Change the local ip address of the interface to 0.
		 * This will also delete the destination route.
		 */
		if(!card->u.c.slarp_timer) {
			if_data2 = (struct sockaddr_in *)&if_info.ifr_dstaddr;
			if_data2->sin_addr.s_addr = 0;
			if_data2->sin_family = AF_INET;
			err = devinet_ioctl(SIOCSIFDSTADDR, &if_info);
		} else {
			if_data1 = (struct sockaddr_in *)&if_info.ifr_addr;
			if_data1->sin_addr.s_addr = 0;
			if_data1->sin_family = AF_INET;
			err = devinet_ioctl(SIOCSIFADDR,&if_info);
		
		}
#else
		/* set the point-to-point IP address to 0.0.0.0 */
		dev->pa_dstaddr = 0; 
		err = ip_rt_kill(&route);
#endif
		if(err) {
			printk(KERN_INFO
				"%s: Remove route %s failed, (err %d)\n",
					card->devname, in_ntoa(remote_IP_addr),
					err);
		} else {
			((chdlc_private_area_t *)dev->priv)->route_status =
				NO_ROUTE;
                        printk(KERN_INFO "%s: Dynamic route removed: %s\n",
                                        card->devname, in_ntoa(local_IP_addr)); 
			chdlc_priv_area->route_removed = 1;
		}
		break;
	}

        set_fs(fs);                     /* Restore file system */

        /* Once we've processed the route, stop polling */
        card->poll = NULL;

}


/*=============================================================================
 * Store a UDP management packet for later processing.
 */

static int store_udp_mgmt_pkt(char udp_pkt_src, sdla_t* card,
                                struct sk_buff *skb, struct net_device* dev,
                                chdlc_private_area_t* chdlc_priv_area )
{
	int udp_pkt_stored = 0;

	if(!chdlc_priv_area->udp_pkt_lgth &&
	  (skb->len <= MAX_LGTH_UDP_MGNT_PKT)) {
        	chdlc_priv_area->udp_pkt_lgth = skb->len;
		chdlc_priv_area->udp_pkt_src = udp_pkt_src;
       		memcpy(chdlc_priv_area->udp_pkt_data, skb->data, skb->len);
		chdlc_priv_area->timer_int_enabled = TMR_INT_ENABLED_UDP;
		udp_pkt_stored = 1;
	}

#ifdef LINUX_2_1
	dev_kfree_skb(skb);
#else
	if(udp_pkt_src == UDP_PKT_FRM_STACK)
		dev_kfree_skb(skb, FREE_WRITE);
	else
                dev_kfree_skb(skb, FREE_READ);
#endif
	
	return(udp_pkt_stored);
}


/*=============================================================================
 * Process UDP management packet.
 */

static int process_udp_mgmt_pkt(sdla_t* card, struct net_device* dev,
				chdlc_private_area_t* chdlc_priv_area ) 
{
	unsigned char *buf;
	unsigned int frames, len;
	struct sk_buff *new_skb;
	unsigned short buffer_length, real_len;
	unsigned long data_ptr;
	unsigned data_length;
	int udp_mgmt_req_valid = 1;
	CHDLC_MAILBOX_STRUCT *mb = card->mbox;
	SHARED_MEMORY_INFO_STRUCT *flags = card->u.c.flags;
	chdlc_udp_pkt_t *chdlc_udp_pkt;
	struct timeval tv;
	int err;
	char ut_char;

	chdlc_udp_pkt = (chdlc_udp_pkt_t *) chdlc_priv_area->udp_pkt_data;

	switch(chdlc_udp_pkt->cblock.command