[linux-block.git] / net / can / raw.c

/*
 * raw.c - Raw sockets for protocol family CAN
 *
 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of Volkswagen nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * Alternatively, provided that this notice is retained in full, this
 * software may be distributed under the terms of the GNU General
 * Public License ("GPL") version 2, in which case the provisions of the
 * GPL apply INSTEAD OF those given above.
 *
 * The provided data structures and external interfaces from this code
 * are not restricted to be used by modules with a GPL compatible license.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 * Send feedback to <socketcan-users@lists.berlios.de>
 *
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/uio.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/socket.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <linux/can.h>
#include <linux/can/core.h>
#include <linux/can/raw.h>
#include <net/sock.h>
#include <net/net_namespace.h>

#define CAN_RAW_VERSION CAN_VERSION
static __initdata const char banner[] =
	KERN_INFO "can: raw protocol (rev " CAN_RAW_VERSION ")\n";

MODULE_DESCRIPTION("PF_CAN raw protocol");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
MODULE_ALIAS("can-proto-1");

#define MASK_ALL 0

/*
 * A raw socket has a list of can_filters attached to it, each receiving
 * the CAN frames matching that filter.  If the filter list is empty,
 * no CAN frames will be received by the socket.  The default after
 * opening the socket, is to have one filter which receives all frames.
 * The filter list is allocated dynamically with the exception of the
 * list containing only one item.  This common case is optimized by
 * storing the single filter in dfilter, to avoid using dynamic memory.
 */

struct raw_sock {
	struct sock sk;
	int bound;
	int ifindex;
	struct notifier_block notifier;
	int loopback;
	int recv_own_msgs;
	int count;                 /* number of active filters */
	struct can_filter dfilter; /* default/single filter */
	struct can_filter *filter; /* pointer to filter(s) */
	can_err_mask_t err_mask;
};

static inline struct raw_sock *raw_sk(const struct sock *sk)
{
	return (struct raw_sock *)sk;
}

static void raw_rcv(struct sk_buff *skb, void *data)
{
	struct sock *sk = (struct sock *)data;
	struct raw_sock *ro = raw_sk(sk);
	struct sockaddr_can *addr;

	/* check the received tx sock reference */
	if (!ro->recv_own_msgs && skb->sk == sk)
		return;

	/* clone the given skb to be able to enqueue it into the rcv queue */
	skb = skb_clone(skb, GFP_ATOMIC);
	if (!skb)
		return;

	/*
	 *  Put the datagram to the queue so that raw_recvmsg() can
	 *  get it from there.  We need to pass the interface index to
	 *  raw_recvmsg().  We pass a whole struct sockaddr_can in skb->cb
	 *  containing the interface index.
	 */

	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
	addr = (struct sockaddr_can *)skb->cb;
	memset(addr, 0, sizeof(*addr));
	addr->can_family  = AF_CAN;
	addr->can_ifindex = skb->dev->ifindex;

	if (sock_queue_rcv_skb(sk, skb) < 0)
		kfree_skb(skb);
}

static int raw_enable_filters(struct net_device *dev, struct sock *sk,
			      struct can_filter *filter, int count)
{
	int err = 0;
	int i;

	for (i = 0; i < count; i++) {
		err = can_rx_register(dev, filter[i].can_id,
				      filter[i].can_mask,
				      raw_rcv, sk, "raw");
		if (err) {
			/* clean up successfully registered filters */
			while (--i >= 0)
				can_rx_unregister(dev, filter[i].can_id,
						  filter[i].can_mask,
						  raw_rcv, sk);
			break;
		}
	}

	return err;
}

static int raw_enable_errfilter(struct net_device *dev, struct sock *sk,
				can_err_mask_t err_mask)
{
	int err = 0;

	if (err_mask)
		err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG,
				      raw_rcv, sk, "raw");

	return err;
}

static void raw_disable_filters(struct net_device *dev, struct sock *sk,
			      struct can_filter *filter, int count)
{
	int i;

	for (i = 0; i < count; i++)
		can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
				  raw_rcv, sk);
}

static inline void raw_disable_errfilter(struct net_device *dev,
					 struct sock *sk,
					 can_err_mask_t err_mask)

{
	if (err_mask)
		can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG,
				  raw_rcv, sk);
}

static inline void raw_disable_allfilters(struct net_device *dev,
					  struct sock *sk)
{
	struct raw_sock *ro = raw_sk(sk);

	raw_disable_filters(dev, sk, ro->filter, ro->count);
	raw_disable_errfilter(dev, sk, ro->err_mask);
}

static int raw_enable_allfilters(struct net_device *dev, struct sock *sk)
{
	struct raw_sock *ro = raw_sk(sk);
	int err;

	err = raw_enable_filters(dev, sk, ro->filter, ro->count);
	if (!err) {
		err = raw_enable_errfilter(dev, sk, ro->err_mask);
		if (err)
			raw_disable_filters(dev, sk, ro->filter, ro->count);
	}

	return err;
}

static int raw_notifier(struct notifier_block *nb,
			unsigned long msg, void *data)
{
	struct net_device *dev = (struct net_device *)data;
	struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
	struct sock *sk = &ro->sk;

	if (!net_eq(dev_net(dev), &init_net))
		return NOTIFY_DONE;

	if (dev->type != ARPHRD_CAN)
		return NOTIFY_DONE;

	if (ro->ifindex != dev->ifindex)
		return NOTIFY_DONE;

	switch (msg) {

	case NETDEV_UNREGISTER:
		lock_sock(sk);
		/* remove current filters & unregister */
		if (ro->bound)
			raw_disable_allfilters(dev, sk);

		if (ro->count > 1)
			kfree(ro->filter);

		ro->ifindex = 0;
		ro->bound   = 0;
		ro->count   = 0;
		release_sock(sk);

		sk->sk_err = ENODEV;
		if (!sock_flag(sk, SOCK_DEAD))
			sk->sk_error_report(sk);
		break;

	case NETDEV_DOWN:
		sk->sk_err = ENETDOWN;
		if (!sock_flag(sk, SOCK_DEAD))
			sk->sk_error_report(sk);
		break;
	}

	return NOTIFY_DONE;
}

static int raw_init(struct sock *sk)
{
	struct raw_sock *ro = raw_sk(sk);

	ro->bound            = 0;
	ro->ifindex          = 0;

	/* set default filter to single entry dfilter */
	ro->dfilter.can_id   = 0;
	ro->dfilter.can_mask = MASK_ALL;
	ro->filter           = &ro->dfilter;
	ro->count            = 1;

	/* set default loopback behaviour */
	ro->loopback         = 1;
	ro->recv_own_msgs    = 0;

	/* set notifier */
	ro->notifier.notifier_call = raw_notifier;

	register_netdevice_notifier(&ro->notifier);

	return 0;
}

static int raw_release(struct socket *sock)
{
	struct sock *sk = sock->sk;
	struct raw_sock *ro = raw_sk(sk);

	unregister_netdevice_notifier(&ro->notifier);

	lock_sock(sk);

	/* remove current filters & unregister */
	if (ro->bound) {
		if (ro->ifindex) {
			struct net_device *dev;

			dev = dev_get_by_index(&init_net, ro->ifindex);
			if (dev) {
				raw_disable_allfilters(dev, sk);
				dev_put(dev);
			}
		} else
			raw_disable_allfilters(NULL, sk);
	}

	if (ro->count > 1)
		kfree(ro->filter);

	ro->ifindex = 0;
	ro->bound   = 0;
	ro->count   = 0;

	sock_orphan(sk);
	sock->sk = NULL;

	release_sock(sk);
	sock_put(sk);

	return 0;
}

static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
{
	struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
	struct sock *sk = sock->sk;
	struct raw_sock *ro = raw_sk(sk);
	int ifindex;
	int err = 0;
	int notify_enetdown = 0;

	if (len < sizeof(*addr))
		return -EINVAL;

	lock_sock(sk);

	if (ro->bound && addr->can_ifindex == ro->ifindex)
		goto out;

	if (addr->can_ifindex) {
		struct net_device *dev;

		dev = dev_get_by_index(&init_net, addr->can_ifindex);
		if (!dev) {
			err = -ENODEV;
			goto out;
		}
		if (dev->type != ARPHRD_CAN) {
			dev_put(dev);
			err = -ENODEV;
			goto out;
		}
		if (!(dev->flags & IFF_UP))
			notify_enetdown = 1;

		ifindex = dev->ifindex;

		/* filters set by default/setsockopt */
		err = raw_enable_allfilters(dev, sk);
		dev_put(dev);
	} else {
		ifindex = 0;

		/* filters set by default/setsockopt */
		err = raw_enable_allfilters(NULL, sk);
	}

	if (!err) {
		if (ro->bound) {
			/* unregister old filters */
			if (ro->ifindex) {
				struct net_device *dev;

				dev = dev_get_by_index(&init_net, ro->ifindex);
				if (dev) {
					raw_disable_allfilters(dev, sk);
					dev_put(dev);
				}
			} else
				raw_disable_allfilters(NULL, sk);
		}
		ro->ifindex = ifindex;
		ro->bound = 1;
	}

 out:
	release_sock(sk);

	if (notify_enetdown) {
		sk->sk_err = ENETDOWN;
		if (!sock_flag(sk, SOCK_DEAD))
			sk->sk_error_report(sk);
	}

	return err;
}

static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
		       int *len, int peer)
{
	struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
	struct sock *sk = sock->sk;
	struct raw_sock *ro = raw_sk(sk);

	if (peer)
		return -EOPNOTSUPP;

	addr->can_family  = AF_CAN;
	addr->can_ifindex = ro->ifindex;

	*len = sizeof(*addr);

	return 0;
}

static int raw_setsockopt(struct socket *sock, int level, int optname,
			  char __user *optval, int optlen)
{
	struct sock *sk = sock->sk;
	struct raw_sock *ro = raw_sk(sk);
	struct can_filter *filter = NULL;  /* dyn. alloc'ed filters */
	struct can_filter sfilter;         /* single filter */
	struct net_device *dev = NULL;
	can_err_mask_t err_mask = 0;
	int count = 0;
	int err = 0;

	if (level != SOL_CAN_RAW)
		return -EINVAL;
	if (optlen < 0)
		return -EINVAL;

	switch (optname) {

	case CAN_RAW_FILTER:
		if (optlen % sizeof(struct can_filter) != 0)
			return -EINVAL;

		count = optlen / sizeof(struct can_filter);

		if (count > 1) {
			/* filter does not fit into dfilter => alloc space */
			filter = kmalloc(optlen, GFP_KERNEL);
			if (!filter)
				return -ENOMEM;

			if (copy_from_user(filter, optval, optlen)) {
				kfree(filter);
				return -EFAULT;
			}
		} else if (count == 1) {
			if (copy_from_user(&sfilter, optval, optlen))
				return -EFAULT;
		}

		lock_sock(sk);

		if (ro->bound && ro->ifindex)
			dev = dev_get_by_index(&init_net, ro->ifindex);

		if (ro->bound) {
			/* (try to) register the new filters */
			if (count == 1)
				err = raw_enable_filters(dev, sk, &sfilter, 1);
			else
				err = raw_enable_filters(dev, sk, filter,
							 count);
			if (err) {
				if (count > 1)
					kfree(filter);
				goto out_fil;
			}

			/* remove old filter registrations */
			raw_disable_filters(dev, sk, ro->filter, ro->count);
		}

		/* remove old filter space */
		if (ro->count > 1)
			kfree(ro->filter);

		/* link new filters to the socket */
		if (count == 1) {
			/* copy filter data for single filter */
			ro->dfilter = sfilter;
			filter = &ro->dfilter;
		}
		ro->filter = filter;
		ro->count  = count;

 out_fil:
		if (dev)
			dev_put(dev);

		release_sock(sk);

		break;

	case CAN_RAW_ERR_FILTER:
		if (optlen != sizeof(err_mask))
			return -EINVAL;

		if (copy_from_user(&err_mask, optval, optlen))
			return -EFAULT;

		err_mask &= CAN_ERR_MASK;

		lock_sock(sk);

		if (ro->bound && ro->ifindex)
			dev = dev_get_by_index(&init_net, ro->ifindex);

		/* remove current error mask */
		if (ro->bound) {
			/* (try to) register the new err_mask */
			err = raw_enable_errfilter(dev, sk, err_mask);

			if (err)
				goto out_err;

			/* remove old err_mask registration */
			raw_disable_errfilter(dev, sk, ro->err_mask);
		}

		/* link new err_mask to the socket */
		ro->err_mask = err_mask;

 out_err:
		if (dev)
			dev_put(dev);

		release_sock(sk);

		break;

	case CAN_RAW_LOOPBACK:
		if (optlen != sizeof(ro->loopback))
			return -EINVAL;

		if (copy_from_user(&ro->loopback, optval, optlen))
			return -EFAULT;

		break;

	case CAN_RAW_RECV_OWN_MSGS:
		if (optlen != sizeof(ro->recv_own_msgs))
			return -EINVAL;

		if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
			return -EFAULT;

		break;

	default:
		return -ENOPROTOOPT;
	}
	return err;
}

static int raw_getsockopt(struct socket *sock, int level, int optname,
			  char __user *optval, int __user *optlen)
{
	struct sock *sk = sock->sk;
	struct raw_sock *ro = raw_sk(sk);
	int len;
	void *val;
	int err = 0;

	if (level != SOL_CAN_RAW)
		return -EINVAL;
	if (get_user(len, optlen))
		return -EFAULT;
	if (len < 0)
		return -EINVAL;

	switch (optname) {

	case CAN_RAW_FILTER:
		lock_sock(sk);
		if (ro->count > 0) {
			int fsize = ro->count * sizeof(struct can_filter);
			if (len > fsize)
				len = fsize;
			if (copy_to_user(optval, ro->filter, len))
				err = -EFAULT;
		} else
			len = 0;
		release_sock(sk);

		if (!err)
			err = put_user(len, optlen);
		return err;

	case CAN_RAW_ERR_FILTER:
		if (len > sizeof(can_err_mask_t))
			len = sizeof(can_err_mask_t);
		val = &ro->err_mask;
		break;

	case CAN_RAW_LOOPBACK:
		if (len > sizeof(int))
			len = sizeof(int);
		val = &ro->loopback;
		break;

	case CAN_RAW_RECV_OWN_MSGS:
		if (len > sizeof(int))
			len = sizeof(int);
		val = &ro->recv_own_msgs;
		break;

	default:
		return -ENOPROTOOPT;
	}

	if (put_user(len, optlen))
		return -EFAULT;
	if (copy_to_user(optval, val, len))
		return -EFAULT;
	return 0;
}

static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
		       struct msghdr *msg, size_t size)
{
	struct sock *sk = sock->sk;
	struct raw_sock *ro = raw_sk(sk);
	struct sk_buff *skb;
	struct net_device *dev;
	int ifindex;
	int err;

	if (msg->msg_name) {
		struct sockaddr_can *addr =
			(struct sockaddr_can *)msg->msg_name;

		if (addr->can_family != AF_CAN)
			return -EINVAL;

		ifindex = addr->can_ifindex;
	} else
		ifindex = ro->ifindex;

	if (size != sizeof(struct can_frame))
		return -EINVAL;

	dev = dev_get_by_index(&init_net, ifindex);
	if (!dev)
		return -ENXIO;

	skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT,
				  &err);
	if (!skb)
		goto put_dev;

	err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
	if (err < 0)
		goto free_skb;
	err = sock_tx_timestamp(msg, sk, skb_tx(skb));
	if (err < 0)
		goto free_skb;
	skb->dev = dev;
	skb->sk  = sk;

	err = can_send(skb, ro->loopback);

	dev_put(dev);

	if (err)
		goto send_failed;

	return size;

free_skb:
	kfree_skb(skb);
put_dev:
	dev_put(dev);
send_failed:
	return err;
}

static int raw_recvmsg(struct kiocb *iocb, struct socket *sock,
		       struct msghdr *msg, size_t size, int flags)
{
	struct sock *sk = sock->sk;
	struct sk_buff *skb;
	int err = 0;
	int noblock;

	noblock =  flags & MSG_DONTWAIT;
	flags   &= ~MSG_DONTWAIT;

	skb = skb_recv_datagram(sk, flags, noblock, &err);
	if (!skb)
		return err;

	if (size < skb->len)
		msg->msg_flags |= MSG_TRUNC;
	else
		size = skb->len;

	err = memcpy_toiovec(msg->msg_iov, skb->data, size);
	if (err < 0) {
		skb_free_datagram(sk, skb);
		return err;
	}

	sock_recv_timestamp(msg, sk, skb);

	if (msg->msg_name) {
		msg->msg_namelen = sizeof(struct sockaddr_can);
		memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
	}

	skb_free_datagram(sk, skb);

	return size;
}

static struct proto_ops raw_ops __read_mostly = {
	.family        = PF_CAN,
	.release       = raw_release,
	.bind          = raw_bind,
	.connect       = sock_no_connect,
	.socketpair    = sock_no_socketpair,
	.accept        = sock_no_accept,
	.getname       = raw_getname,
	.poll          = datagram_poll,
	.ioctl         = NULL,		/* use can_ioctl() from af_can.c */
	.listen        = sock_no_listen,
	.shutdown      = sock_no_shutdown,
	.setsockopt    = raw_setsockopt,
	.getsockopt    = raw_getsockopt,
	.sendmsg       = raw_sendmsg,
	.recvmsg       = raw_recvmsg,
	.mmap          = sock_no_mmap,
	.sendpage      = sock_no_sendpage,
};

static struct proto raw_proto __read_mostly = {
	.name       = "CAN_RAW",
	.owner      = THIS_MODULE,
	.obj_size   = sizeof(struct raw_sock),
	.init       = raw_init,
};

static struct can_proto raw_can_proto __read_mostly = {
	.type       = SOCK_RAW,
	.protocol   = CAN_RAW,
	.capability = -1,
	.ops        = &raw_ops,
	.prot       = &raw_proto,
};

static __init int raw_module_init(void)
{
	int err;

	printk(banner);

	err = can_proto_register(&raw_can_proto);
	if (err < 0)
		printk(KERN_ERR "can: registration of raw protocol failed\n");

	return err;
}

static __exit void raw_module_exit(void)
{
	can_proto_unregister(&raw_can_proto);
}

module_init(raw_module_init);
module_exit(raw_module_exit);
Commit	Line	Data
c18ce101 OH	1	/*
	2	* raw.c - Raw sockets for protocol family CAN
	3	*
	4	* Copyright (c) 2002-2007 Volkswagen Group Electronic Research
	5	* All rights reserved.
	6	*
	7	* Redistribution and use in source and binary forms, with or without
	8	* modification, are permitted provided that the following conditions
	9	* are met:
	10	* 1. Redistributions of source code must retain the above copyright
	11	* notice, this list of conditions and the following disclaimer.
	12	* 2. Redistributions in binary form must reproduce the above copyright
	13	* notice, this list of conditions and the following disclaimer in the
	14	* documentation and/or other materials provided with the distribution.
	15	* 3. Neither the name of Volkswagen nor the names of its contributors
	16	* may be used to endorse or promote products derived from this software
	17	* without specific prior written permission.
	18	*
	19	* Alternatively, provided that this notice is retained in full, this
	20	* software may be distributed under the terms of the GNU General
	21	* Public License ("GPL") version 2, in which case the provisions of the
	22	* GPL apply INSTEAD OF those given above.
	23	*
	24	* The provided data structures and external interfaces from this code
	25	* are not restricted to be used by modules with a GPL compatible license.
	26	*
	27	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	28	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	29	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	30	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	31	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	32	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	33	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	34	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	35	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	36	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	37	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
	38	* DAMAGE.
	39	*
	40	* Send feedback to <socketcan-users@lists.berlios.de>
	41	*
	42	*/
	43
	44	#include <linux/module.h>
	45	#include <linux/init.h>
	46	#include <linux/uio.h>
	47	#include <linux/net.h>
	48	#include <linux/netdevice.h>
	49	#include <linux/socket.h>
	50	#include <linux/if_arp.h>
	51	#include <linux/skbuff.h>
	52	#include <linux/can.h>
	53	#include <linux/can/core.h>
	54	#include <linux/can/raw.h>
	55	#include <net/sock.h>
	56	#include <net/net_namespace.h>
	57
	58	#define CAN_RAW_VERSION CAN_VERSION
	59	static __initdata const char banner[] =
	60	KERN_INFO "can: raw protocol (rev " CAN_RAW_VERSION ")\n";
	61
	62	MODULE_DESCRIPTION("PF_CAN raw protocol");
	63	MODULE_LICENSE("Dual BSD/GPL");
	64	MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
b13bb2e9	65	MODULE_ALIAS("can-proto-1");
c18ce101 OH	66
	67	#define MASK_ALL 0
	68
	69	/*
	70	* A raw socket has a list of can_filters attached to it, each receiving
	71	* the CAN frames matching that filter. If the filter list is empty,
	72	* no CAN frames will be received by the socket. The default after
	73	* opening the socket, is to have one filter which receives all frames.
	74	* The filter list is allocated dynamically with the exception of the
	75	* list containing only one item. This common case is optimized by
	76	* storing the single filter in dfilter, to avoid using dynamic memory.
	77	*/
	78
	79	struct raw_sock {
	80	struct sock sk;
	81	int bound;
	82	int ifindex;
	83	struct notifier_block notifier;
	84	int loopback;
	85	int recv_own_msgs;
	86	int count; /* number of active filters */
	87	struct can_filter dfilter; /* default/single filter */
	88	struct can_filter filter; / pointer to filter(s) */
	89	can_err_mask_t err_mask;
	90	};
	91
	92	static inline struct raw_sock raw_sk(const struct sock sk)
	93	{
	94	return (struct raw_sock *)sk;
	95	}
	96
	97	static void raw_rcv(struct sk_buff skb, void data)
	98	{
	99	struct sock sk = (struct sock )data;
	100	struct raw_sock *ro = raw_sk(sk);
	101	struct sockaddr_can *addr;
c18ce101	102
1fa17d4b OH	103	/* check the received tx sock reference */
	104	if (!ro->recv_own_msgs && skb->sk == sk)
	105	return;
	106
	107	/* clone the given skb to be able to enqueue it into the rcv queue */
	108	skb = skb_clone(skb, GFP_ATOMIC);
	109	if (!skb)
	110	return;
c18ce101 OH	111
	112	/*
	113	* Put the datagram to the queue so that raw_recvmsg() can
	114	* get it from there. We need to pass the interface index to
	115	* raw_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
	116	* containing the interface index.
	117	*/
	118
	119	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
	120	addr = (struct sockaddr_can *)skb->cb;
	121	memset(addr, 0, sizeof(*addr));
	122	addr->can_family = AF_CAN;
	123	addr->can_ifindex = skb->dev->ifindex;
	124
a219994b	125	if (sock_queue_rcv_skb(sk, skb) < 0)
c18ce101 OH	126	kfree_skb(skb);
	127	}
	128
	129	static int raw_enable_filters(struct net_device dev, struct sock sk,
a219994b	130	struct can_filter *filter, int count)
c18ce101 OH	131	{
	132	int err = 0;
	133	int i;
	134
	135	for (i = 0; i < count; i++) {
	136	err = can_rx_register(dev, filter[i].can_id,
	137	filter[i].can_mask,
	138	raw_rcv, sk, "raw");
	139	if (err) {
	140	/* clean up successfully registered filters */
	141	while (--i >= 0)
	142	can_rx_unregister(dev, filter[i].can_id,
	143	filter[i].can_mask,
	144	raw_rcv, sk);
	145	break;
	146	}
	147	}
	148
	149	return err;
	150	}
	151
	152	static int raw_enable_errfilter(struct net_device dev, struct sock sk,
	153	can_err_mask_t err_mask)
	154	{
	155	int err = 0;
	156
	157	if (err_mask)
	158	err = can_rx_register(dev, 0, err_mask \| CAN_ERR_FLAG,
	159	raw_rcv, sk, "raw");
	160
	161	return err;
	162	}
	163
	164	static void raw_disable_filters(struct net_device dev, struct sock sk,
a219994b	165	struct can_filter *filter, int count)
c18ce101 OH	166	{
	167	int i;
	168
	169	for (i = 0; i < count; i++)
	170	can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
	171	raw_rcv, sk);
	172	}
	173
	174	static inline void raw_disable_errfilter(struct net_device *dev,
	175	struct sock *sk,
	176	can_err_mask_t err_mask)
	177
	178	{
	179	if (err_mask)
	180	can_rx_unregister(dev, 0, err_mask \| CAN_ERR_FLAG,
	181	raw_rcv, sk);
	182	}
	183
	184	static inline void raw_disable_allfilters(struct net_device *dev,
	185	struct sock *sk)
	186	{
	187	struct raw_sock *ro = raw_sk(sk);
	188
	189	raw_disable_filters(dev, sk, ro->filter, ro->count);
	190	raw_disable_errfilter(dev, sk, ro->err_mask);
	191	}
	192
	193	static int raw_enable_allfilters(struct net_device dev, struct sock sk)
	194	{
	195	struct raw_sock *ro = raw_sk(sk);
	196	int err;
	197
	198	err = raw_enable_filters(dev, sk, ro->filter, ro->count);
	199	if (!err) {
	200	err = raw_enable_errfilter(dev, sk, ro->err_mask);
	201	if (err)
	202	raw_disable_filters(dev, sk, ro->filter, ro->count);
	203	}
	204
	205	return err;
	206	}
	207
	208	static int raw_notifier(struct notifier_block *nb,
	209	unsigned long msg, void *data)
	210	{
	211	struct net_device dev = (struct net_device )data;
	212	struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
	213	struct sock *sk = &ro->sk;
	214
721499e8	215	if (!net_eq(dev_net(dev), &init_net))
c18ce101 OH	216	return NOTIFY_DONE;
	217
	218	if (dev->type != ARPHRD_CAN)
	219	return NOTIFY_DONE;
	220
	221	if (ro->ifindex != dev->ifindex)
	222	return NOTIFY_DONE;
	223
	224	switch (msg) {
	225
	226	case NETDEV_UNREGISTER:
	227	lock_sock(sk);
	228	/* remove current filters & unregister */
	229	if (ro->bound)
	230	raw_disable_allfilters(dev, sk);
	231
	232	if (ro->count > 1)
	233	kfree(ro->filter);
	234
	235	ro->ifindex = 0;
	236	ro->bound = 0;
	237	ro->count = 0;
	238	release_sock(sk);
	239
	240	sk->sk_err = ENODEV;
	241	if (!sock_flag(sk, SOCK_DEAD))
	242	sk->sk_error_report(sk);
	243	break;
	244
	245	case NETDEV_DOWN:
	246	sk->sk_err = ENETDOWN;
	247	if (!sock_flag(sk, SOCK_DEAD))
	248	sk->sk_error_report(sk);
	249	break;
	250	}
	251
	252	return NOTIFY_DONE;
	253	}
	254
	255	static int raw_init(struct sock *sk)
	256	{
	257	struct raw_sock *ro = raw_sk(sk);
	258
	259	ro->bound = 0;
	260	ro->ifindex = 0;
	261
	262	/* set default filter to single entry dfilter */
	263	ro->dfilter.can_id = 0;
	264	ro->dfilter.can_mask = MASK_ALL;
	265	ro->filter = &ro->dfilter;
	266	ro->count = 1;
	267
	268	/* set default loopback behaviour */
	269	ro->loopback = 1;
	270	ro->recv_own_msgs = 0;
	271
	272	/* set notifier */
	273	ro->notifier.notifier_call = raw_notifier;
	274
	275	register_netdevice_notifier(&ro->notifier);
	276
	277	return 0;
	278	}
	279
280	static int raw_release(struct socket *sock)
281	{
282	struct sock *sk = sock->sk;
283	struct raw_sock *ro = raw_sk(sk);
284
285	unregister_netdevice_notifier(&ro->notifier);
286
287	lock_sock(sk);
288
289	/* remove current filters & unregister */
290	if (ro->bound) {
291	if (ro->ifindex) {
292	struct net_device *dev;
293
294	dev = dev_get_by_index(&init_net, ro->ifindex);
295	if (dev) {
296	raw_disable_allfilters(dev, sk);
297	dev_put(dev);
298	}
299	} else
300	raw_disable_allfilters(NULL, sk);
301	}
302
303	if (ro->count > 1)
304	kfree(ro->filter);
305
306	ro->ifindex = 0;
307	ro->bound = 0;
308	ro->count = 0;
309
f7e5cc0c LW	310	sock_orphan(sk);
	311	sock->sk = NULL;
	312
c18ce101 OH	313	release_sock(sk);
	314	sock_put(sk);
	315
	316	return 0;
	317	}
	318
	319	static int raw_bind(struct socket sock, struct sockaddr uaddr, int len)
	320	{
	321	struct sockaddr_can addr = (struct sockaddr_can )uaddr;
	322	struct sock *sk = sock->sk;
	323	struct raw_sock *ro = raw_sk(sk);
	324	int ifindex;
	325	int err = 0;
	326	int notify_enetdown = 0;
	327
	328	if (len < sizeof(*addr))
	329	return -EINVAL;
	330
	331	lock_sock(sk);
	332
	333	if (ro->bound && addr->can_ifindex == ro->ifindex)
	334	goto out;
	335
	336	if (addr->can_ifindex) {
	337	struct net_device *dev;
	338
	339	dev = dev_get_by_index(&init_net, addr->can_ifindex);
	340	if (!dev) {
	341	err = -ENODEV;
	342	goto out;
	343	}
	344	if (dev->type != ARPHRD_CAN) {
	345	dev_put(dev);
	346	err = -ENODEV;
	347	goto out;
	348	}
	349	if (!(dev->flags & IFF_UP))
	350	notify_enetdown = 1;
	351
	352	ifindex = dev->ifindex;
	353
	354	/* filters set by default/setsockopt */
	355	err = raw_enable_allfilters(dev, sk);
	356	dev_put(dev);
c18ce101 OH	357	} else {
	358	ifindex = 0;
	359
	360	/* filters set by default/setsockopt */
	361	err = raw_enable_allfilters(NULL, sk);
	362	}
	363
	364	if (!err) {
	365	if (ro->bound) {
	366	/* unregister old filters */
	367	if (ro->ifindex) {
	368	struct net_device *dev;
	369
	370	dev = dev_get_by_index(&init_net, ro->ifindex);
	371	if (dev) {
	372	raw_disable_allfilters(dev, sk);
	373	dev_put(dev);
	374	}
	375	} else
	376	raw_disable_allfilters(NULL, sk);
	377	}
	378	ro->ifindex = ifindex;
	379	ro->bound = 1;
	380	}
	381
	382	out:
	383	release_sock(sk);
	384
	385	if (notify_enetdown) {
	386	sk->sk_err = ENETDOWN;
	387	if (!sock_flag(sk, SOCK_DEAD))
	388	sk->sk_error_report(sk);
	389	}
	390
	391	return err;
	392	}
	393
	394	static int raw_getname(struct socket sock, struct sockaddr uaddr,
	395	int *len, int peer)
	396	{
	397	struct sockaddr_can addr = (struct sockaddr_can )uaddr;
	398	struct sock *sk = sock->sk;
	399	struct raw_sock *ro = raw_sk(sk);
	400
	401	if (peer)
	402	return -EOPNOTSUPP;
	403
	404	addr->can_family = AF_CAN;
	405	addr->can_ifindex = ro->ifindex;
	406
	407	len = sizeof(addr);
	408
	409	return 0;
	410	}
	411
	412	static int raw_setsockopt(struct socket *sock, int level, int optname,
	413	char __user *optval, int optlen)
	414	{
	415	struct sock *sk = sock->sk;
	416	struct raw_sock *ro = raw_sk(sk);
	417	struct can_filter filter = NULL; / dyn. alloc'ed filters */
	418	struct can_filter sfilter; /* single filter */
	419	struct net_device *dev = NULL;
	420	can_err_mask_t err_mask = 0;
421	int count = 0;
422	int err = 0;
423
424	if (level != SOL_CAN_RAW)
425	return -EINVAL;
426	if (optlen < 0)
427	return -EINVAL;
428
429	switch (optname) {
430
431	case CAN_RAW_FILTER:
432	if (optlen % sizeof(struct can_filter) != 0)
433	return -EINVAL;
434
435	count = optlen / sizeof(struct can_filter);
436
437	if (count > 1) {
438	/* filter does not fit into dfilter => alloc space */
439	filter = kmalloc(optlen, GFP_KERNEL);
440	if (!filter)
441	return -ENOMEM;
442
3f91bd42	443	if (copy_from_user(filter, optval, optlen)) {
c18ce101	444	kfree(filter);
3f91bd42	445	return -EFAULT;
c18ce101 OH	446	}
c18ce101 OH	447	} else if (count == 1) {
3f91bd42 SR	448	if (copy_from_user(&sfilter, optval, optlen))
3f91bd42 SR	449	return -EFAULT;
c18ce101 OH	450	}
	451
	452	lock_sock(sk);
	453
	454	if (ro->bound && ro->ifindex)
	455	dev = dev_get_by_index(&init_net, ro->ifindex);
	456
	457	if (ro->bound) {
	458	/* (try to) register the new filters */
	459	if (count == 1)
	460	err = raw_enable_filters(dev, sk, &sfilter, 1);
	461	else
	462	err = raw_enable_filters(dev, sk, filter,
	463	count);
	464	if (err) {
	465	if (count > 1)
	466	kfree(filter);
c18ce101 OH	467	goto out_fil;
	468	}
	469
	470	/* remove old filter registrations */
	471	raw_disable_filters(dev, sk, ro->filter, ro->count);
	472	}
	473
	474	/* remove old filter space */
	475	if (ro->count > 1)
	476	kfree(ro->filter);
	477
	478	/* link new filters to the socket */
	479	if (count == 1) {
	480	/* copy filter data for single filter */
	481	ro->dfilter = sfilter;
	482	filter = &ro->dfilter;
	483	}
	484	ro->filter = filter;
	485	ro->count = count;
	486
	487	out_fil:
	488	if (dev)
	489	dev_put(dev);
	490
	491	release_sock(sk);
	492
	493	break;
	494
	495	case CAN_RAW_ERR_FILTER:
	496	if (optlen != sizeof(err_mask))
	497	return -EINVAL;
	498
3f91bd42 SR	499	if (copy_from_user(&err_mask, optval, optlen))
3f91bd42 SR	500	return -EFAULT;
c18ce101 OH	501
	502	err_mask &= CAN_ERR_MASK;
	503
	504	lock_sock(sk);
	505
	506	if (ro->bound && ro->ifindex)
	507	dev = dev_get_by_index(&init_net, ro->ifindex);
	508
	509	/* remove current error mask */
	510	if (ro->bound) {
	511	/* (try to) register the new err_mask */
	512	err = raw_enable_errfilter(dev, sk, err_mask);
	513
	514	if (err)
	515	goto out_err;
	516
	517	/* remove old err_mask registration */
	518	raw_disable_errfilter(dev, sk, ro->err_mask);
	519	}
	520
	521	/* link new err_mask to the socket */
	522	ro->err_mask = err_mask;
	523
	524	out_err:
	525	if (dev)
	526	dev_put(dev);
	527
	528	release_sock(sk);
	529
	530	break;
	531
	532	case CAN_RAW_LOOPBACK:
	533	if (optlen != sizeof(ro->loopback))
	534	return -EINVAL;
	535
3f91bd42 SR	536	if (copy_from_user(&ro->loopback, optval, optlen))
3f91bd42 SR	537	return -EFAULT;
c18ce101 OH	538
	539	break;
	540
	541	case CAN_RAW_RECV_OWN_MSGS:
	542	if (optlen != sizeof(ro->recv_own_msgs))
	543	return -EINVAL;
	544
3f91bd42 SR	545	if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
3f91bd42 SR	546	return -EFAULT;
c18ce101 OH	547
	548	break;
	549
	550	default:
	551	return -ENOPROTOOPT;
	552	}
	553	return err;
	554	}
	555
	556	static int raw_getsockopt(struct socket *sock, int level, int optname,
	557	char __user optval, int __user optlen)
	558	{
	559	struct sock *sk = sock->sk;
	560	struct raw_sock *ro = raw_sk(sk);
	561	int len;
	562	void *val;
	563	int err = 0;
	564
	565	if (level != SOL_CAN_RAW)
	566	return -EINVAL;
	567	if (get_user(len, optlen))
	568	return -EFAULT;
	569	if (len < 0)
	570	return -EINVAL;
	571
	572	switch (optname) {
	573
	574	case CAN_RAW_FILTER:
	575	lock_sock(sk);
	576	if (ro->count > 0) {
	577	int fsize = ro->count * sizeof(struct can_filter);
	578	if (len > fsize)
	579	len = fsize;
653252c2 PE	580	if (copy_to_user(optval, ro->filter, len))
653252c2 PE	581	err = -EFAULT;
c18ce101 OH	582	} else
	583	len = 0;
	584	release_sock(sk);
	585
	586	if (!err)
	587	err = put_user(len, optlen);
	588	return err;
	589
	590	case CAN_RAW_ERR_FILTER:
	591	if (len > sizeof(can_err_mask_t))
	592	len = sizeof(can_err_mask_t);
	593	val = &ro->err_mask;
	594	break;
	595
	596	case CAN_RAW_LOOPBACK:
	597	if (len > sizeof(int))
	598	len = sizeof(int);
	599	val = &ro->loopback;
	600	break;
	601
	602	case CAN_RAW_RECV_OWN_MSGS:
	603	if (len > sizeof(int))
	604	len = sizeof(int);
	605	val = &ro->recv_own_msgs;
	606	break;
	607
	608	default:
	609	return -ENOPROTOOPT;
	610	}
	611
	612	if (put_user(len, optlen))
	613	return -EFAULT;
	614	if (copy_to_user(optval, val, len))
	615	return -EFAULT;
	616	return 0;
	617	}
	618
	619	static int raw_sendmsg(struct kiocb iocb, struct socket sock,
	620	struct msghdr *msg, size_t size)
	621	{
	622	struct sock *sk = sock->sk;
	623	struct raw_sock *ro = raw_sk(sk);
	624	struct sk_buff *skb;
	625	struct net_device *dev;
	626	int ifindex;
	627	int err;
	628
	629	if (msg->msg_name) {
	630	struct sockaddr_can *addr =
	631	(struct sockaddr_can *)msg->msg_name;
	632
	633	if (addr->can_family != AF_CAN)
	634	return -EINVAL;
	635
	636	ifindex = addr->can_ifindex;
	637	} else
	638	ifindex = ro->ifindex;
	639
7f2d38eb OH	640	if (size != sizeof(struct can_frame))
	641	return -EINVAL;
	642
c18ce101 OH	643	dev = dev_get_by_index(&init_net, ifindex);
	644	if (!dev)
	645	return -ENXIO;
	646
	647	skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT,
	648	&err);
ebad5c09 IJ	649	if (!skb)
ebad5c09 IJ	650	goto put_dev;
c18ce101 OH	651
c18ce101 OH	652	err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
51f31cab PO	653	if (err < 0)
	654	goto free_skb;
	655	err = sock_tx_timestamp(msg, sk, skb_tx(skb));
ebad5c09 IJ	656	if (err < 0)
ebad5c09 IJ	657	goto free_skb;
c18ce101 OH	658	skb->dev = dev;
	659	skb->sk = sk;
	660
	661	err = can_send(skb, ro->loopback);
	662
	663	dev_put(dev);
	664
	665	if (err)
ebad5c09	666	goto send_failed;
c18ce101 OH	667
c18ce101 OH	668	return size;
ebad5c09 IJ	669
	670	free_skb:
	671	kfree_skb(skb);
	672	put_dev:
	673	dev_put(dev);
	674	send_failed:
	675	return err;
c18ce101 OH	676	}
	677
	678	static int raw_recvmsg(struct kiocb iocb, struct socket sock,
	679	struct msghdr *msg, size_t size, int flags)
	680	{
	681	struct sock *sk = sock->sk;
	682	struct sk_buff *skb;
a219994b	683	int err = 0;
c18ce101 OH	684	int noblock;
	685
	686	noblock = flags & MSG_DONTWAIT;
	687	flags &= ~MSG_DONTWAIT;
	688
a219994b	689	skb = skb_recv_datagram(sk, flags, noblock, &err);
c18ce101	690	if (!skb)
a219994b	691	return err;
c18ce101 OH	692
	693	if (size < skb->len)
	694	msg->msg_flags \|= MSG_TRUNC;
	695	else
	696	size = skb->len;
	697
a219994b UT	698	err = memcpy_toiovec(msg->msg_iov, skb->data, size);
a219994b UT	699	if (err < 0) {
c18ce101	700	skb_free_datagram(sk, skb);
a219994b	701	return err;
c18ce101 OH	702	}
	703
	704	sock_recv_timestamp(msg, sk, skb);
	705
	706	if (msg->msg_name) {
	707	msg->msg_namelen = sizeof(struct sockaddr_can);
	708	memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
	709	}
	710
	711	skb_free_datagram(sk, skb);
	712
	713	return size;
	714	}
	715
	716	static struct proto_ops raw_ops __read_mostly = {
	717	.family = PF_CAN,
	718	.release = raw_release,
	719	.bind = raw_bind,
	720	.connect = sock_no_connect,
	721	.socketpair = sock_no_socketpair,
	722	.accept = sock_no_accept,
	723	.getname = raw_getname,
	724	.poll = datagram_poll,
	725	.ioctl = NULL, /* use can_ioctl() from af_can.c */
	726	.listen = sock_no_listen,
	727	.shutdown = sock_no_shutdown,
	728	.setsockopt = raw_setsockopt,
	729	.getsockopt = raw_getsockopt,
	730	.sendmsg = raw_sendmsg,
	731	.recvmsg = raw_recvmsg,
	732	.mmap = sock_no_mmap,
	733	.sendpage = sock_no_sendpage,
	734	};
	735
	736	static struct proto raw_proto __read_mostly = {
	737	.name = "CAN_RAW",
	738	.owner = THIS_MODULE,
	739	.obj_size = sizeof(struct raw_sock),
	740	.init = raw_init,
	741	};
	742
	743	static struct can_proto raw_can_proto __read_mostly = {
	744	.type = SOCK_RAW,
	745	.protocol = CAN_RAW,
	746	.capability = -1,
	747	.ops = &raw_ops,
	748	.prot = &raw_proto,
	749	};
	750
	751	static __init int raw_module_init(void)
	752	{
	753	int err;
	754
	755	printk(banner);
	756
	757	err = can_proto_register(&raw_can_proto);
	758	if (err < 0)
	759	printk(KERN_ERR "can: registration of raw protocol failed\n");
	760
	761	return err;
	762	}
	763
	764	static __exit void raw_module_exit(void)
	765	{
766	can_proto_unregister(&raw_can_proto);
767	}
768
769	module_init(raw_module_init);
770	module_exit(raw_module_exit);