[CAN]: Add raw protocol
This patch adds the CAN raw protocol.
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/can/Kconfig b/net/can/Kconfig
index 8b92790..4718d1f 100644
--- a/net/can/Kconfig
+++ b/net/can/Kconfig
@@ -15,3 +15,14 @@
If you want CAN support you should say Y here and also to the
specific driver for your controller(s) below.
+
+config CAN_RAW
+ tristate "Raw CAN Protocol (raw access with CAN-ID filtering)"
+ depends on CAN
+ default N
+ ---help---
+ The raw CAN protocol option offers access to the CAN bus via
+ the BSD socket API. You probably want to use the raw socket in
+ most cases where no higher level protocol is being used. The raw
+ socket has several filter options e.g. ID masking / error frames.
+ To receive/send raw CAN messages, use AF_CAN with protocol CAN_RAW.
diff --git a/net/can/Makefile b/net/can/Makefile
index 4c7563c..86f1cf2 100644
--- a/net/can/Makefile
+++ b/net/can/Makefile
@@ -4,3 +4,6 @@
obj-$(CONFIG_CAN) += can.o
can-objs := af_can.o proc.o
+
+obj-$(CONFIG_CAN_RAW) += can-raw.o
+can-raw-objs := raw.o
diff --git a/net/can/raw.c b/net/can/raw.c
new file mode 100644
index 0000000..aeefd14
--- /dev/null
+++ b/net/can/raw.c
@@ -0,0 +1,763 @@
+/*
+ * 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>");
+
+#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;
+ int error;
+
+ if (!ro->recv_own_msgs) {
+ /* check the received tx sock reference */
+ if (skb->sk == sk) {
+ kfree_skb(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;
+
+ error = sock_queue_rcv_skb(sk, skb);
+ if (error < 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 (dev->nd_net != &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;
+
+ 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;
+
+ err = copy_from_user(filter, optval, optlen);
+ if (err) {
+ kfree(filter);
+ return err;
+ }
+ } else if (count == 1) {
+ err = copy_from_user(&sfilter, optval, optlen);
+ if (err)
+ return err;
+ }
+
+ 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;
+
+ err = copy_from_user(&err_mask, optval, optlen);
+ if (err)
+ return err;
+
+ 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;
+
+ err = copy_from_user(&ro->loopback, optval, optlen);
+
+ break;
+
+ case CAN_RAW_RECV_OWN_MSGS:
+ if (optlen != sizeof(ro->recv_own_msgs))
+ return -EINVAL;
+
+ err = copy_from_user(&ro->recv_own_msgs, optval, optlen);
+
+ 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;
+ err = copy_to_user(optval, ro->filter, len);
+ } 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;
+
+ 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) {
+ dev_put(dev);
+ return err;
+ }
+
+ err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
+ if (err < 0) {
+ kfree_skb(skb);
+ dev_put(dev);
+ return err;
+ }
+ skb->dev = dev;
+ skb->sk = sk;
+
+ err = can_send(skb, ro->loopback);
+
+ dev_put(dev);
+
+ if (err)
+ return err;
+
+ return size;
+}
+
+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 error = 0;
+ int noblock;
+
+ noblock = flags & MSG_DONTWAIT;
+ flags &= ~MSG_DONTWAIT;
+
+ skb = skb_recv_datagram(sk, flags, noblock, &error);
+ if (!skb)
+ return error;
+
+ if (size < skb->len)
+ msg->msg_flags |= MSG_TRUNC;
+ else
+ size = skb->len;
+
+ error = memcpy_toiovec(msg->msg_iov, skb->data, size);
+ if (error < 0) {
+ skb_free_datagram(sk, skb);
+ return error;
+ }
+
+ 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);