cregit-Linux how code gets into the kernel

Release 4.8 net/can/raw.c

Directory: net/can
/*
 * 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.
 *
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/uio.h>
#include <linux/net.h>
#include <linux/slab.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/skb.h>
#include <linux/can/raw.h>
#include <net/sock.h>
#include <net/net_namespace.h>


#define CAN_RAW_VERSION CAN_VERSION

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 uniqframe {
	
int skbcnt;
	
const struct sk_buff *skb;
	
unsigned int join_rx_count;
};


struct raw_sock {
	
struct sock sk;
	
int bound;
	
int ifindex;
	
struct notifier_block notifier;
	
int loopback;
	
int recv_own_msgs;
	
int fd_frames;
	
int join_filters;
	
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;
	
struct uniqframe __percpu *uniq;
};

/*
 * Return pointer to store the extra msg flags for raw_recvmsg().
 * We use the space of one unsigned int beyond the 'struct sockaddr_can'
 * in skb->cb.
 */

static inline unsigned int *raw_flags(struct sk_buff *skb) { sock_skb_cb_check_size(sizeof(struct sockaddr_can) + sizeof(unsigned int)); /* return pointer after struct sockaddr_can */ return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]); }

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

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static void raw_rcv(struct sk_buff *oskb, void *data) { struct sock *sk = (struct sock *)data; struct raw_sock *ro = raw_sk(sk); struct sockaddr_can *addr; struct sk_buff *skb; unsigned int *pflags; /* check the received tx sock reference */ if (!ro->recv_own_msgs && oskb->sk == sk) return; /* do not pass non-CAN2.0 frames to a legacy socket */ if (!ro->fd_frames && oskb->len != CAN_MTU) return; /* eliminate multiple filter matches for the same skb */ if (this_cpu_ptr(ro->uniq)->skb == oskb && this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) { if (ro->join_filters) { this_cpu_inc(ro->uniq->join_rx_count); /* drop frame until all enabled filters matched */ if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count) return; } else { return; } } else { this_cpu_ptr(ro->uniq)->skb = oskb; this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt; this_cpu_ptr(ro->uniq)->join_rx_count = 1; /* drop first frame to check all enabled filters? */ if (ro->join_filters && ro->count > 1) return; } /* clone the given skb to be able to enqueue it into the rcv queue */ skb = skb_clone(oskb, 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. */ sock_skb_cb_check_size(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; /* add CAN specific message flags for raw_recvmsg() */ pflags = raw_flags(skb); *pflags = 0; if (oskb->sk) *pflags |= MSG_DONTROUTE; if (oskb->sk == sk) *pflags |= MSG_CONFIRM; if (sock_queue_rcv_skb(sk, skb) < 0) kfree_skb(skb); }

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urs thuermannurs thuermann20.61%110.00%
eyal birgereyal birger10.31%110.00%
Total326100.00%10100.00%


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; }

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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; }

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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); }

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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); }

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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); }

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oliver hartkoppoliver hartkopp53100.00%1100.00%
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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; }

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static int raw_notifier(struct notifier_block *nb, unsigned long msg, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); 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; }

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jiri pirkojiri pirko52.33%125.00%
Total215100.00%4100.00%


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; ro->fd_frames = 0; ro->join_filters = 0; /* alloc_percpu provides zero'ed memory */ ro->uniq = alloc_percpu(struct uniqframe); if (unlikely(!ro->uniq)) return -ENOMEM; /* set notifier */ ro->notifier.notifier_call = raw_notifier; register_netdevice_notifier(&ro->notifier); return 0; }

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oliver hartkoppoliver hartkopp135100.00%4100.00%
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static int raw_release(struct socket *sock) { struct sock *sk = sock->sk; struct raw_sock *ro; if (!sk) return 0; 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; free_percpu(ro->uniq); sock_orphan(sk); sock->sk = NULL; release_sock(sk); sock_put(sk); return 0; }

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lothar wassmannlothar wassmann116.21%125.00%
Total177100.00%4100.00%


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; }

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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; memset(addr, 0, sizeof(*addr)); addr->can_family = AF_CAN; addr->can_ifindex = ro->ifindex; *len = sizeof(*addr); return 0; }

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oliver hartkoppoliver hartkopp8887.13%150.00%
eric dumazeteric dumazet1312.87%150.00%
Total101100.00%2100.00%


static int raw_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned 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; 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 = memdup_user(optval, optlen); if (IS_ERR(filter)) return PTR_ERR(filter); } else if (count == 1) { if (copy_from_user(&sfilter, optval, sizeof(sfilter))) 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; case CAN_RAW_FD_FRAMES: if (optlen != sizeof(ro->fd_frames)) return -EINVAL; if (copy_from_user(&ro->fd_frames, optval, optlen)) return -EFAULT; break; case CAN_RAW_JOIN_FILTERS: if (optlen != sizeof(ro->join_filters)) return -EINVAL; if (copy_from_user(&ro->join_filters, optval, optlen)) return -EFAULT; break; default: return -ENOPROTOOPT; } return err; }

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julia lawalljulia lawall60.94%114.29%
eric dumazeteric dumazet40.62%114.29%
david s. millerdavid s. miller10.16%114.29%
Total641100.00%7100.00%


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; case CAN_RAW_FD_FRAMES: if (len > sizeof(int)) len = sizeof(int); val = &ro->fd_frames; break; case CAN_RAW_JOIN_FILTERS: if (len > sizeof(int)) len = sizeof(int); val = &ro->join_filters; break; default: return -ENOPROTOOPT; } if (put_user(len, optlen)) return -EFAULT; if (copy_to_user(optval, val, len)) return -EFAULT; return 0; }

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oliver hartkoppoliver hartkopp34798.02%375.00%
pavel emelianovpavel emelianov71.98%125.00%
Total354100.00%4100.00%


static int raw_sendmsg(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) { DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); if (msg->msg_namelen < sizeof(*addr)) return -EINVAL; if (addr->can_family != AF_CAN) return -EINVAL; ifindex = addr->can_ifindex; } else ifindex = ro->ifindex; if (ro->fd_frames) { if (unlikely(size != CANFD_MTU && size != CAN_MTU)) return -EINVAL; } else { if (unlikely(size