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

 *
 */
static int irda_sendmsg_dgram(struct socket *sock, struct msghdr *msg,
			      int len, struct scm_cookie *scm)
{
	struct sock *sk = sock->sk;
	struct irda_sock *self;
	struct sk_buff *skb;
	unsigned char *asmptr;
	int err;
	
	IRDA_DEBUG(4, __FUNCTION__ "(), len=%d\n", len);
	
	if (msg->msg_flags & ~MSG_DONTWAIT)
		return -EINVAL;

	if (sk->shutdown & SEND_SHUTDOWN) {
		send_sig(SIGPIPE, current, 0);
		return -EPIPE;
	}

	if (sk->state != TCP_ESTABLISHED)
		return -ENOTCONN;

	self = sk->protinfo.irda;
	ASSERT(self != NULL, return -1;);

	/*  
	 * Check that we don't send out to big frames. This is an unreliable 
	 * service, so we have no fragmentation and no coalescence 
	 */
	if (len > self->max_data_size) {
		IRDA_DEBUG(0, __FUNCTION__ "(), Warning to much data! "
			   "Chopping frame from %d to %d bytes!\n", len, 
			   self->max_data_size);
		len = self->max_data_size;
	}

	skb = sock_alloc_send_skb(sk, len + self->max_header_size, 
				  msg->msg_flags & MSG_DONTWAIT, &err);
	if (!skb)
		return -ENOBUFS;

	skb_reserve(skb, self->max_header_size);
	
	IRDA_DEBUG(4, __FUNCTION__ "(), appending user data\n");
	asmptr = skb->h.raw = skb_put(skb, len);
	memcpy_fromiovec(asmptr, msg->msg_iov, len);

	/* 
	 * Just send the message to TinyTP, and let it deal with possible 
	 * errors. No need to duplicate all that here
	 */
	err = irttp_udata_request(self->tsap, skb);
	if (err) {
		IRDA_DEBUG(0, __FUNCTION__ "(), err=%d\n", err);
		return err;
	}
	return len;
}

/*
 * Function irda_sendmsg_ultra (sock, msg, len, scm)
 *
 *    Send message down to IrLMP for the unreliable Ultra
 *    packet service...
 */
#ifdef CONFIG_IRDA_ULTRA
static int irda_sendmsg_ultra(struct socket *sock, struct msghdr *msg,
			      int len, struct scm_cookie *scm)
{
	struct sock *sk = sock->sk;
	struct irda_sock *self;
	struct sk_buff *skb;
	unsigned char *asmptr;
	int err;
	
	IRDA_DEBUG(4, __FUNCTION__ "(), len=%d\n", len);
	
	if (msg->msg_flags & ~MSG_DONTWAIT)
		return -EINVAL;

	if (sk->shutdown & SEND_SHUTDOWN) {
		send_sig(SIGPIPE, current, 0);
		return -EPIPE;
	}

	self = sk->protinfo.irda;
	ASSERT(self != NULL, return -1;);

	/*  
	 * Check that we don't send out to big frames. This is an unreliable 
	 * service, so we have no fragmentation and no coalescence 
	 */
	if (len > self->max_data_size) {
		IRDA_DEBUG(0, __FUNCTION__ "(), Warning to much data! "
			   "Chopping frame from %d to %d bytes!\n", len, 
			   self->max_data_size);
		len = self->max_data_size;
	}

	skb = sock_alloc_send_skb(sk, len + self->max_header_size, 
				  msg->msg_flags & MSG_DONTWAIT, &err);
	if (!skb)
		return -ENOBUFS;

	skb_reserve(skb, self->max_header_size);
	
	IRDA_DEBUG(4, __FUNCTION__ "(), appending user data\n");
	asmptr = skb->h.raw = skb_put(skb, len);
	memcpy_fromiovec(asmptr, msg->msg_iov, len);

	err = irlmp_connless_data_request(self->lsap, skb);
	if (err) {
		IRDA_DEBUG(0, __FUNCTION__ "(), err=%d\n", err);
		return err;
	}
	return len;
}
#endif /* CONFIG_IRDA_ULTRA */

/*
 * Function irda_shutdown (sk, how)
 *
 *    
 *
 */
static int irda_shutdown(struct socket *sock, int how)
{
	struct irda_sock *self;
	struct sock *sk = sock->sk;

	self = sk->protinfo.irda;
	ASSERT(self != NULL, return -1;);

	IRDA_DEBUG(1, __FUNCTION__ "(%p)\n", self);

	sk->state       = TCP_CLOSE;
	sk->shutdown   |= SEND_SHUTDOWN;
	sk->state_change(sk);

	if (self->iriap) {
		iriap_close(self->iriap);
		self->iriap = NULL;
	}

	if (self->tsap) {
		irttp_disconnect_request(self->tsap, NULL, P_NORMAL);
		irttp_close_tsap(self->tsap);
		self->tsap = NULL;
	}

	/* A few cleanup so the socket look as good as new... */
	self->rx_flow = self->tx_flow = FLOW_START;	/* needed ??? */
	self->daddr = DEV_ADDR_ANY;	/* Until we get re-connected */
	self->saddr = 0x0;		/* so IrLMP assign us any link */

        return 0;
}

/*
 * Function irda_poll (file, sock, wait)
 *
 *    
 *
 */
static unsigned int irda_poll(struct file * file, struct socket *sock, 
			      poll_table *wait)
{
	struct sock *sk = sock->sk;
	unsigned int mask;
	struct irda_sock *self;

	IRDA_DEBUG(4, __FUNCTION__ "()\n");

	self = sk->protinfo.irda;
	poll_wait(file, sk->sleep, wait);
	mask = 0;

	/* Exceptional events? */
	if (sk->err)
		mask |= POLLERR;
	if (sk->shutdown & RCV_SHUTDOWN) {
		IRDA_DEBUG(0, __FUNCTION__ "(), POLLHUP\n");
		mask |= POLLHUP;
	}

	/* Readable? */
	if (!skb_queue_empty(&sk->receive_queue)) {
		IRDA_DEBUG(4, "Socket is readable\n");
		mask |= POLLIN | POLLRDNORM;
	}

	/* Connection-based need to check for termination and startup */
	switch (sk->type) {
	case SOCK_STREAM:
		if (sk->state == TCP_CLOSE) {
			IRDA_DEBUG(0, __FUNCTION__ "(), POLLHUP\n");
			mask |= POLLHUP;
		}

		if (sk->state == TCP_ESTABLISHED) {
			if ((self->tx_flow == FLOW_START) && 
			    (sk->sndbuf - (int)atomic_read(&sk->wmem_alloc) >= SOCK_MIN_WRITE_SPACE))
			{
				mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
			}
		}
		break;
	case SOCK_SEQPACKET:
		if ((self->tx_flow == FLOW_START) && 
		    (sk->sndbuf - (int)atomic_read(&sk->wmem_alloc) >= SOCK_MIN_WRITE_SPACE))
		{	
			mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
		}
		break;
	case SOCK_DGRAM:
		if (sk->sndbuf - (int)atomic_read(&sk->wmem_alloc) >= SOCK_MIN_WRITE_SPACE)
			mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
		break;
	default:
		break;
	}		
	return mask;
}

/*
 * Function irda_ioctl (sock, cmd, arg)
 *
 *    
 *
 */
static int irda_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
	struct sock *sk = sock->sk;

	IRDA_DEBUG(4, __FUNCTION__ "(), cmd=%#x\n", cmd);
	
	switch (cmd) {
	case TIOCOUTQ: {
		long amount;
		amount = sk->sndbuf - atomic_read(&sk->wmem_alloc);
		if (amount < 0)
			amount = 0;
		if (put_user(amount, (unsigned int *)arg))
			return -EFAULT;
		return 0;
	}
	
	case TIOCINQ: {
		struct sk_buff *skb;
		long amount = 0L;
		/* These two are safe on a single CPU system as only user tasks fiddle here */
		if ((skb = skb_peek(&sk->receive_queue)) != NULL)
			amount = skb->len;
		if (put_user(amount, (unsigned int *)arg))
			return -EFAULT;
		return 0;
	}
	
	case SIOCGSTAMP:
		if (sk != NULL) {
			if (sk->stamp.tv_sec == 0)
				return -ENOENT;
			if (copy_to_user((void *)arg, &sk->stamp, 
					 sizeof(struct timeval)))
				return -EFAULT;
			return 0;
		}
		return -EINVAL;
		
	case SIOCGIFADDR:
	case SIOCSIFADDR:
	case SIOCGIFDSTADDR:
	case SIOCSIFDSTADDR:
	case SIOCGIFBRDADDR:
	case SIOCSIFBRDADDR:
	case SIOCGIFNETMASK:
	case SIOCSIFNETMASK:
	case SIOCGIFMETRIC:
	case SIOCSIFMETRIC:
		return -EINVAL;		
	default:
		IRDA_DEBUG(1, __FUNCTION__ "(), doing device ioctl!\n");
		return dev_ioctl(cmd, (void *) arg);
	}

	/*NOTREACHED*/
	return 0;
}

/*
 * Function irda_setsockopt (sock, level, optname, optval, optlen)
 *
 *    Set some options for the socket
 *
 */
static int irda_setsockopt(struct socket *sock, int level, int optname, 
			   char *optval, int optlen)
{
 	struct sock *sk = sock->sk;
	struct irda_sock *self;
	struct irda_ias_set    *ias_opt;
	struct ias_object      *ias_obj;
	struct ias_attrib *	ias_attr;	/* Attribute in IAS object */
	int opt;
	
	self = sk->protinfo.irda;
	ASSERT(self != NULL, return -1;);

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

	if (level != SOL_IRLMP)
		return -ENOPROTOOPT;
		
	switch (optname) {
	case IRLMP_IAS_SET:
		/* The user want to add an attribute to an existing IAS object
		 * (in the IAS database) or to create a new object with this
		 * attribute.
		 * We first query IAS to know if the object exist, and then
		 * create the right attribute...
		 */

		if (optlen != 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, (char *)optval, optlen)) {
			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') {
			if(self->ias_obj == NULL) {
				kfree(ias_opt);
				return -EINVAL;
			}
			ias_obj = self->ias_obj;
		} else
			ias_obj = irias_find_object(ias_opt->irda_class_name);

		/* Only ROOT can mess with the global IAS database.
		 * Users can only add attributes to 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;
		}

		/* If the object doesn't exist, create it */
		if(ias_obj == (struct ias_object *) NULL) {
			/* Create a new object */
			ias_obj = irias_new_object(ias_opt->irda_class_name,
						   jiffies);
		}

		/* Do we have the attribute already ? */
		if(irias_find_attrib(ias_obj, ias_opt->irda_attrib_name)) {
			kfree(ias_opt);
			return -EINVAL;
		}

		/* Look at the type */
		switch(ias_opt->irda_attrib_type) {
		case IAS_INTEGER:
			/* Add an integer attribute */
			irias_add_integer_attrib(
				ias_obj,
				ias_opt->irda_attrib_name, 
				ias_opt->attribute.irda_attrib_int,
				IAS_USER_ATTR);
			break;
		case IAS_OCT_SEQ:
			/* Check length */
			if(ias_opt->attribute.irda_attrib_octet_seq.len >
			   IAS_MAX_OCTET_STRING) {
				kfree(ias_opt);
				return -EINVAL;
			}
			/* Add an octet sequence attribute */
			irias_add_octseq_attrib(
			      ias_obj,
			      ias_opt->irda_attrib_name, 
			      ias_opt->attribute.irda_attrib_octet_seq.octet_seq,
			      ias_opt->attribute.irda_attrib_octet_seq.len,
			      IAS_USER_ATTR);
			break;
		case IAS_STRING:
			/* Should check charset & co */
			/* Check length */
			if(ias_opt->attribute.irda_attrib_string.len >
			   IAS_MAX_STRING) {
				kfree(ias_opt);
				return -EINVAL;
			}
			/* NULL terminate the string (avoid troubles) */
			ias_opt->attribute.irda_attrib_string.string[ias_opt->attribute.irda_attrib_string.len] = '\0';
			/* Add a string attribute */
			irias_add_string_attrib(
				ias_obj,
				ias_opt->irda_attrib_name, 
				ias_opt->attribute.irda_attrib_string.string,
				IAS_USER_ATTR);
			break;
		default :
			kfree(ias_opt);
			return -EINVAL;
		}
		irias_insert_object(ias_obj);
		kfree(ias_opt);
		break;
	case IRLMP_IAS_DEL:
		/* The user want to delete an object from our local IAS
		 * database. We just need to query the IAS, check is the
		 * object is not owned by the kernel and delete it.
		 */

		if (optlen != 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, (char *)optval, optlen)) {
			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;
		}

		/* 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, __FUNCTION__ 
				   "(), attempting to delete a kernel attribute\n");
			kfree(ias_opt);
			return -EPERM;
		}

		/* Remove the attribute (and maybe the object) */
		irias_delete_attrib(ias_obj, ias_attr);
		kfree(ias_opt);
		break;
	case IRLMP_MAX_SDU_SIZE:
		if (optlen < sizeof(int))
			return -EINVAL;
	
		if (get_user(opt, (int *)optval))
			return -EFAULT;
		
		/* Only possible for a seqpacket service (TTP with SAR) */
		if (sk->type != SOCK_SEQPACKET) {
			IRDA_DEBUG(2, __FUNCTION__ 
				   "(), setting max_sdu_size = %d\n", opt);
			self->max_sdu_size_rx = opt;
		} else {
			WARNING(__FUNCTION__ 
				"(), not allowed to set MAXSDUSIZE for this "
				"socket type!\n");
			return -ENOPROTOOPT;
		}
		break;
	case IRLMP_HINTS_SET:
		if (optlen < sizeof(int))