af_irda.c

linux 内核源代码

		else
			ias_obj = irias_find_object(ias_opt->irda_class_name);
		if(ias_obj == (struct ias_object *) NULL) {
			kfree(ias_opt);
			return -EINVAL;
		}

		/* Only ROOT can mess with the global IAS database.
		 * Users can only del attributes from the object associated
		 * with the socket they own - Jean II */
		if((!capable(CAP_NET_ADMIN)) &&
		   ((ias_obj == NULL) || (ias_obj != self->ias_obj))) {
			kfree(ias_opt);
			return -EPERM;
		}

		/* 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;
		}

		/* Check is the user space own the object */
		if(ias_attr->value->owner != IAS_USER_ATTR) {
			IRDA_DEBUG(1, "%s(), attempting to delete a kernel attribute\n", __FUNCTION__);
			kfree(ias_opt);
			return -EPERM;
		}

		/* Remove the attribute (and maybe the object) */
		irias_delete_attrib(ias_obj, ias_attr, 1);
		kfree(ias_opt);
		break;
	case IRLMP_MAX_SDU_SIZE:
		if (optlen < sizeof(int))
			return -EINVAL;

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

		/* Only possible for a seqpacket service (TTP with SAR) */
		if (sk->sk_type != SOCK_SEQPACKET) {
			IRDA_DEBUG(2, "%s(), setting max_sdu_size = %d\n",
				   __FUNCTION__, opt);
			self->max_sdu_size_rx = opt;
		} else {
			IRDA_WARNING("%s: not allowed to set MAXSDUSIZE for this socket type!\n",
				     __FUNCTION__);
			return -ENOPROTOOPT;
		}
		break;
	case IRLMP_HINTS_SET:
		if (optlen < sizeof(int))
			return -EINVAL;

		/* The input is really a (__u8 hints[2]), easier as an int */
		if (get_user(opt, (int __user *)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;

		/* The input is really a (__u8 hints[2]), easier as an int */
		if (get_user(opt, (int __user *)optval))
			return -EFAULT;

		/* Set the new hint mask */
		self->mask.word = (__u16) opt;
		/* Mask out extension bits */
		self->mask.word &= 0x7f7f;
		/* Check if no bits */
		if(!self->mask.word)
			self->mask.word = 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 __user *optval, int __user *optlen)
{
	struct sock *sk = sock->sk;
	struct irda_sock *self = irda_sk(sk);
	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;

	IRDA_DEBUG(2, "%s(%p)\n", __FUNCTION__, 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.word,
						    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(ias_opt, 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(optval, 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(ias_opt, 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) {
			IRDA_WARNING("%s: busy with a previous query\n",
				     __FUNCTION__);
			kfree(ias_opt);
			return -EBUSY;
		}

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

		if (self->iriap == NULL) {
			kfree(ias_opt);
			return -ENOMEM;
		}

		/* Treat unexpected wakeup 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 yet finished (or failed) */
		if (wait_event_interruptible(self->query_wait,
					     (self->iriap == NULL))) {
			/* pending request uses copy of ias_opt-content
			 * we can free it regardless! */
			kfree(ias_opt);
			/* Treat signals as disconnect */
			return -EHOSTUNREACH;
		}

		/* 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(optval, 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 __user *)optval))
			return -EFAULT;

		/* Tell IrLMP we want to be notified */
		irlmp_update_client(self->ckey, self->mask.word,
				    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->cachedaddr) {
			int ret = 0;

			IRDA_DEBUG(1, "%s(), nothing discovered yet, going to sleep...\n", __FUNCTION__);

			/* Set watchdog timer to expire in <val> ms. */
			self->errno = 0;
			init_timer(&self->watchdog);
			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 */
			__wait_event_interruptible(self->query_wait,
			      (self->cachedaddr != 0 || self->errno == -ETIME),
						   ret);

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

			IRDA_DEBUG(1, "%s(), ...waking up !\n", __FUNCTION__);

			if (ret != 0)
				return ret;
		}
		else
			IRDA_DEBUG(1, "%s(), found immediately !\n",
				   __FUNCTION__);

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

		/* Check if the we got some results */
		if (!self->cachedaddr)
			return -EAGAIN;		/* Didn't find any devices */
		daddr = self->cachedaddr;
		/* Cleanup */
		self->cachedaddr = 0;

		/* We return the daddr of the device that trigger the
		 * wakeup. As irlmp pass us only the new devices, we
		 * are sure that it's not an old device.
		 * If the user want more details, he should query
		 * the whole discovery log and pick one device...
		 */
		if (put_user(daddr, (int __user *)optval))
			return -EFAULT;

		break;
	default:
		return -ENOPROTOOPT;
	}

	return 0;
}

static struct net_proto_family irda_family_ops = {
	.family = PF_IRDA,
	.create = irda_create,
	.owner	= THIS_MODULE,
};

static const struct proto_ops SOCKOPS_WRAPPED(irda_stream_ops) = {
	.family =	PF_IRDA,
	.owner =	THIS_MODULE,
	.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,
#ifdef CONFIG_COMPAT
	.compat_ioctl =	irda_c