af_irda.c

《嵌入式系统设计与实例开发实验教材二源码》Linux内核移植与编译实验

			return -EINVAL;
	
		if (get_user(opt, (int *)optval))
			return -EFAULT;

		/* Unregister any old registration */
		if (self->skey)
			irlmp_unregister_service(self->skey);

		self->skey = irlmp_register_service((__u16) opt);
		break;
	case IRLMP_HINT_MASK_SET:
		/* As opposed to the previous case which set the hint bits
		 * that we advertise, this one set the filter we use when
		 * making a discovery (nodes which don't match any hint
		 * bit in the mask are not reported).
		 */
		if (optlen < sizeof(int))
			return -EINVAL;
	
		if (get_user(opt, (int *)optval))
			return -EFAULT;

		/* Set the new hint mask */
		self->mask = (__u16) opt;
		/* Mask out extension bits */
		self->mask &= 0x7f7f;
		/* Check if no bits */
		if(!self->mask)
			self->mask = 0xFFFF;

		break;
	default:
		return -ENOPROTOOPT;
	}
	return 0;
}

/*
 * Function irda_extract_ias_value(ias_opt, ias_value)
 *
 *    Translate internal IAS value structure to the user space representation
 *
 * The external representation of IAS values, as we exchange them with
 * user space program is quite different from the internal representation,
 * as stored in the IAS database (because we need a flat structure for
 * crossing kernel boundary).
 * This function transform the former in the latter. We also check
 * that the value type is valid.
 */
static int irda_extract_ias_value(struct irda_ias_set *ias_opt,
				  struct ias_value *ias_value)
{
	/* Look at the type */
	switch (ias_value->type) {
	case IAS_INTEGER:
		/* Copy the integer */
		ias_opt->attribute.irda_attrib_int = ias_value->t.integer;
		break;
	case IAS_OCT_SEQ:
		/* Set length */
		ias_opt->attribute.irda_attrib_octet_seq.len = ias_value->len;
		/* Copy over */
		memcpy(ias_opt->attribute.irda_attrib_octet_seq.octet_seq,
		       ias_value->t.oct_seq, ias_value->len);
		break;
	case IAS_STRING:
		/* Set length */
		ias_opt->attribute.irda_attrib_string.len = ias_value->len;
		ias_opt->attribute.irda_attrib_string.charset = ias_value->charset;
		/* Copy over */
		memcpy(ias_opt->attribute.irda_attrib_string.string,
		       ias_value->t.string, ias_value->len);
		/* NULL terminate the string (avoid troubles) */
		ias_opt->attribute.irda_attrib_string.string[ias_value->len] = '\0';
		break;
	case IAS_MISSING:
	default :
		return -EINVAL;
	}
	
	/* Copy type over */
	ias_opt->irda_attrib_type = ias_value->type;
	
	return 0;
}

/*
 * Function irda_getsockopt (sock, level, optname, optval, optlen)
 *
 *    
 *
 */
static int irda_getsockopt(struct socket *sock, int level, int optname, 
			   char *optval, int *optlen)
{
	struct sock *sk = sock->sk;
	struct irda_sock *self;
	struct irda_device_list list;
	struct irda_device_info *discoveries;
	struct irda_ias_set *	ias_opt;	/* IAS get/query params */
	struct ias_object *	ias_obj;	/* Object in IAS */
	struct ias_attrib *	ias_attr;	/* Attribute in IAS object */
	int daddr = DEV_ADDR_ANY;	/* Dest address for IAS queries */
	int val = 0;
	int len = 0;
	int err;
	int offset, total;

	self = sk->protinfo.irda;

	IRDA_DEBUG(2, __FUNCTION__ "(%p)\n", self);

	if (level != SOL_IRLMP)
		return -ENOPROTOOPT;

	if (get_user(len, optlen))
		return -EFAULT;

	if(len < 0)
		return -EINVAL;
		
	switch (optname) {
	case IRLMP_ENUMDEVICES:
		/* Ask lmp for the current discovery log */
		discoveries = irlmp_get_discoveries(&list.len, self->mask,
						    self->nslots);
		/* Check if the we got some results */
		if (discoveries == NULL)
			return -EAGAIN;		/* Didn't find any devices */
		err = 0;

		/* Write total list length back to client */
		if (copy_to_user(optval, &list, 
				 sizeof(struct irda_device_list) -
				 sizeof(struct irda_device_info)))
			err = -EFAULT;

		/* Offset to first device entry */
		offset = sizeof(struct irda_device_list) - 
			sizeof(struct irda_device_info);

		/* Copy the list itself - watch for overflow */
		if(list.len > 2048)
		{
			err = -EINVAL;
			goto bed;
		}
		total = offset + (list.len * sizeof(struct irda_device_info));
		if (total > len)
			total = len;
		if (copy_to_user(optval+offset, discoveries, total - offset))
			err = -EFAULT;

		/* Write total number of bytes used back to client */
		if (put_user(total, optlen))
			err = -EFAULT;
bed:
		/* Free up our buffer */
		kfree(discoveries);
		if (err)
			return err;
		break;
	case IRLMP_MAX_SDU_SIZE:
		val = self->max_data_size;
		len = sizeof(int);
		if (put_user(len, optlen))
			return -EFAULT;
		
		if (copy_to_user(optval, &val, len))
			return -EFAULT;
		break;
	case IRLMP_IAS_GET:
		/* The user want an object from our local IAS database.
		 * We just need to query the IAS and return the value
		 * that we found */

		/* Check that the user has allocated the right space for us */
		if (len != sizeof(struct irda_ias_set))
			return -EINVAL;

		ias_opt = kmalloc(sizeof(struct irda_ias_set), GFP_ATOMIC);
		if (ias_opt == NULL)
			return -ENOMEM;

		/* Copy query to the driver. */
		if (copy_from_user((char *) ias_opt, (char *)optval, len)) {
			kfree(ias_opt);
		  	return -EFAULT;
		}

		/* Find the object we target.
		 * If the user gives us an empty string, we use the object
		 * associated with this socket. This will workaround
		 * duplicated class name - Jean II */
		if(ias_opt->irda_class_name[0] == '\0')
			ias_obj = self->ias_obj;
		else
			ias_obj = irias_find_object(ias_opt->irda_class_name);
		if(ias_obj == (struct ias_object *) NULL) {
			kfree(ias_opt);
			return -EINVAL;
		}

		/* Find the attribute (in the object) we target */
		ias_attr = irias_find_attrib(ias_obj,
					     ias_opt->irda_attrib_name); 
		if(ias_attr == (struct ias_attrib *) NULL) {
			kfree(ias_opt);
			return -EINVAL;
		}

		/* Translate from internal to user structure */
		err = irda_extract_ias_value(ias_opt, ias_attr->value);
		if(err) {
			kfree(ias_opt);
			return err;
		}

		/* Copy reply to the user */
		if (copy_to_user((char *)optval, (char *) ias_opt,
				 sizeof(struct irda_ias_set))) {
			kfree(ias_opt);
		  	return -EFAULT;
		}
		/* Note : don't need to put optlen, we checked it */
		kfree(ias_opt);
		break;
	case IRLMP_IAS_QUERY:
		/* The user want an object from a remote IAS database.
		 * We need to use IAP to query the remote database and
		 * then wait for the answer to come back. */

		/* Check that the user has allocated the right space for us */
		if (len != sizeof(struct irda_ias_set))
			return -EINVAL;

		ias_opt = kmalloc(sizeof(struct irda_ias_set), GFP_ATOMIC);
		if (ias_opt == NULL)
			return -ENOMEM;

		/* Copy query to the driver. */
		if (copy_from_user((char *) ias_opt, (char *)optval, len)) {
			kfree(ias_opt);
		  	return -EFAULT;
		}

		/* At this point, there are two cases...
		 * 1) the socket is connected - that's the easy case, we
		 *	just query the device we are connected to...
		 * 2) the socket is not connected - the user doesn't want
		 *	to connect and/or may not have a valid service name
		 *	(so can't create a fake connection). In this case,
		 *	we assume that the user pass us a valid destination
		 *	address in the requesting structure...
		 */
		if(self->daddr != DEV_ADDR_ANY) {
			/* We are connected - reuse known daddr */
			daddr = self->daddr;
		} else {
			/* We are not connected, we must specify a valid
			 * destination address */
			daddr = ias_opt->daddr;
			if((!daddr) || (daddr == DEV_ADDR_ANY)) {
				kfree(ias_opt);
				return -EINVAL;
			}
		}

		/* Check that we can proceed with IAP */
		if (self->iriap) {
			WARNING(__FUNCTION__
				"(), busy with a previous query\n");
			kfree(ias_opt);
			return -EBUSY;
		}

		self->iriap = iriap_open(LSAP_ANY, IAS_CLIENT, self,
					 irda_getvalue_confirm);

		/* Treat unexpected signals as disconnect */
		self->errno = -EHOSTUNREACH;

		/* Query remote LM-IAS */
		iriap_getvaluebyclass_request(self->iriap,
					      self->saddr, daddr,
					      ias_opt->irda_class_name,
					      ias_opt->irda_attrib_name);
		/* Wait for answer (if not already failed) */
		if(self->iriap != NULL)
			interruptible_sleep_on(&self->query_wait);
		/* Check what happened */
		if (self->errno)
		{
			kfree(ias_opt);
			/* Requested object/attribute doesn't exist */
			if((self->errno == IAS_CLASS_UNKNOWN) ||
			   (self->errno == IAS_ATTRIB_UNKNOWN))
				return (-EADDRNOTAVAIL);
			else
				return (-EHOSTUNREACH);
		}

		/* Translate from internal to user structure */
		err = irda_extract_ias_value(ias_opt, self->ias_result);
		if (self->ias_result)
			irias_delete_value(self->ias_result);
		if (err) {
			kfree(ias_opt);
			return err;
		}

		/* Copy reply to the user */
		if (copy_to_user((char *)optval, (char *) ias_opt,
				 sizeof(struct irda_ias_set))) {
			kfree(ias_opt);
		  	return -EFAULT;
		}
		/* Note : don't need to put optlen, we checked it */
		kfree(ias_opt);
		break;
	case IRLMP_WAITDEVICE:
		/* This function is just another way of seeing life ;-)
		 * IRLMP_ENUMDEVICES assumes that you have a static network,
		 * and that you just want to pick one of the devices present.
		 * On the other hand, in here we assume that no device is
		 * present and that at some point in the future a device will
		 * come into range. When this device arrive, we just wake
		 * up the caller, so that he has time to connect to it before
		 * the device goes away...
		 * Note : once the node has been discovered for more than a
		 * few second, it won't trigger this function, unless it
		 * goes away and come back changes its hint bits (so we
		 * might call it IRLMP_WAITNEWDEVICE).
		 */

		/* Check that the user is passing us an int */
		if (len != sizeof(int))
			return -EINVAL;
		/* Get timeout in ms (max time we block the caller) */
		if (get_user(val, (int *)optval))
			return -EFAULT;

		/* Tell IrLMP we want to be notified */
		irlmp_update_client(self->ckey, self->mask,
				    irda_selective_discovery_indication,
				    NULL, (void *) self);
		
		/* Do some discovery (and also return cached results) */
		irlmp_discovery_request(self->nslots);
		
		/* Wait until a node is discovered */
		if (!self->cachediscovery) {
			IRDA_DEBUG(1, __FUNCTION__ 
				   "(), nothing discovered yet, going to sleep...\n");

			/* Set watchdog timer to expire in <val> ms. */
			self->watchdog.function = irda_discovery_timeout;
			self->watchdog.data = (unsigned long) self;
			self->watchdog.expires = jiffies + (val * HZ/1000);
			add_timer(&(self->watchdog));

			/* Wait for IR-LMP to call us back */
			interruptible_sleep_on(&self->query_wait);

			/* If watchdog is still activated, kill it! */
			if(timer_pending(&(self->watchdog)))
				del_timer(&(self->watchdog));

			IRDA_DEBUG(1, __FUNCTION__ 
				   "(), ...waking up !\n");
		}
		else
			IRDA_DEBUG(1, __FUNCTION__ 
				   "(), found immediately !\n");

		/* Tell IrLMP that we have been notified */
		irlmp_update_client(self->ckey, self->mask, NULL, NULL, NULL);

		/* Check if the we got some results */
		if (!self->cachediscovery)
			return -EAGAIN;		/* Didn't find any devices */
		/* Cleanup */
		self->cachediscovery = NULL;

		/* Note : We don't return anything to the user.
		 * We could return the device that triggered the wake up,
		 * but it's probably better to force the user to query
		 * the whole discovery log and let him pick one device...
		 */
		break;
	default:
		return -ENOPROTOOPT;
	}
	
	return 0;
}

static struct net_proto_family irda_family_ops =
{
	PF_IRDA,
	irda_create
};

static struct proto_ops SOCKOPS_WRAPPED(irda_stream_ops) = {
	family:		PF_IRDA,
	
	release:	irda_release,
	bind:		irda_bind,
	connect:	irda_connect,
	socketpair:	sock_no_socketpair,
	accept:		irda_accept,
	getname:	irda_getname,
	poll:		irda_poll,
	ioctl:		irda_ioctl,
	listen:		irda_listen,
	shutdown:	irda_shutdown,
	setsockopt:	irda_setsockopt,
	getsockopt:	irda_getsockopt,
	sendmsg:	irda_sendmsg,
	recvmsg:	irda_recvmsg_stream,
	mmap:		sock_no_mmap,
	sendpage:	sock_no_sendpage,
};

static struct proto_ops SOCKOPS_WRAPPED(irda_seqpacket_ops) = {
	family:		PF_IRDA,
	
	release:	irda_release,
	bind:		irda_bind,
	connect:	irda_connect,
	socketpair:	sock_no_socketpair,
	accept:		irda_accept,
	getname:	irda_getname,
	poll:		datagram_poll,
	ioctl:		irda_ioctl,
	listen:		irda_listen,
	shutdown:	irda_shutdown,
	setsockopt:	irda_setsockopt,
	getsockopt:	irda_getsockopt,
	sendmsg:	irda_sendmsg,
	recvmsg:	irda_recvmsg_dgram,
	mmap:		sock_no_mmap,
	sendpage:	sock_no_sendpage,
};

static struct proto_ops SOCKOPS_WRAPPED(irda_dgram_ops) = {
	family:		PF_IRDA,
       
	release:	irda_release,
	bind:		irda_bind,
	connect:	irda_connect,
	socketpair:	sock_no_socketpair,
	accept:		irda_accept,
	getname:	irda_getname,
	poll:		datagram_poll,
	ioctl:		irda_ioctl,
	listen:		irda_listen,
	shutdown:	irda_shutdown,
	setsockopt:	irda_setsockopt,
	getsockopt:	irda_getsockopt,
	sendmsg:	irda_sendmsg_dgram,
	recvmsg:	irda_recvmsg_dgram,
	mmap:		sock_no_mmap,
	sendpage:	sock_no_sendpage,
};

#ifdef CONFIG_IRDA_ULTRA
static struct proto_ops SOCKOPS_WRAPPED(irda_ultra_ops) = {
	family:		PF_IRDA,
       
	release:	irda_release,
	bind:		irda_bind,
	connect:	sock_no_connect,
	socketpair:	sock_no_socketpair,
	accept:		sock_no_accept,
	getname:	irda_getname,
	poll:		datagram_poll,
	ioctl:		irda_ioctl,
	listen:		sock_no_listen,
	shutdown:	irda_shutdown,
	setsockopt:	irda_setsockopt,
	getsockopt:	irda_getsockopt,
	sendmsg:	irda_sendmsg_ultra,
	recvmsg:	irda_recvmsg_dgram,
	mmap:		sock_no_mmap,
	sendpage:	sock_no_sendpage,
};
#endif /* CONFIG_IRDA_ULTRA */

#include <linux/smp_lock.h>
SOCKOPS_WRAP(irda_stream, PF_IRDA);
SOCKOPS_WRAP(irda_seqpacket, PF_IRDA);
SOCKOPS_WRAP(irda_dgram, PF_IRDA);
#ifdef CONFIG_IRDA_ULTRA
SOCKOPS_WRAP(irda_ultra, PF_IRDA);
#endif /* CONFIG_IRDA_ULTRA */

/*
 * Function irda_device_event (this