-#include "gw.h" /* override */
+/*
+ * Copyright: (c) 2012 Czech Technical University in Prague
+ *
+ * Authors:
+ * Radek Matějka <radek.matejka@gmail.com>
+ * Michal Sojka <sojkam1@fel.cvut.cz>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/kthread.h>
-#include <linux/sched.h>
-#include <linux/delay.h>
-#include <linux/wait.h>
-#include <linux/netdevice.h>
-#include <linux/socket.h>
-#include <linux/net.h>
-#include <linux/can/core.h>
+#include <linux/file.h>
+#include <net/sock.h>
#include <linux/can.h>
-#include <net/rtnetlink.h>
+#include <linux/miscdevice.h>
#include "canethgw.h"
-MODULE_LICENSE( "GPL" );
+MODULE_LICENSE("GPL");
-static struct task_struct* eth_to_can, * can_to_eth;
-static struct socket* udp_sock;
-static struct socket* can_sock;
-static struct net_device* can_dev;
+static int cegw_udp2can(void *data);
+static int cegw_udp_send(struct socket *udp_sock, struct can_frame *cf,
+ struct sockaddr_in* addr);
+static int cegw_can2udp(void *data);
+static int cegw_can_send(struct socket *can_sock, struct can_frame *cf);
+static int cegw_thread_start(void *data);
+static int cegw_thread_stop(struct cegw_job *job);
+static void cegw_job_release(struct kref *ref);
-struct can_eth_gw
+static int cegw_udp_send(struct socket *udp_sock, struct can_frame *cf, struct sockaddr_in* addr)
{
- int src_if_idx;
- struct in_addr dst_addr;
- unsigned short dst_port;
- struct hlist_node list;
-};
+ struct msghdr mh;
+ struct kvec vec;
+ int err;
-struct eth_can_gw
-{
- int dst_if_idx;
- struct hlist_node list;
-};
+ mh.msg_name = addr;
+ mh.msg_namelen = sizeof(*addr);
+ mh.msg_control = NULL;
+ mh.msg_controllen = 0;
+ mh.msg_flags = 0;
-HLIST_HEAD( can_eth_job );
-HLIST_HEAD( eth_can_job );
+ vec.iov_base = cf;
+ vec.iov_len = sizeof(*cf);
-struct cegw_setting
-{
- struct can_filter filter;
- int src_idx;
- /* bind on if */
- struct in_addr dst_addr;
- unsigned short dst_port;
-};
+ err = kernel_sendmsg(udp_sock, &mh, &vec, 1, sizeof(*cf));
-/***********************
- * UDP
- ***********************/
+ return err;
+}
-static int gw_udp_recv( void* data )
+static int cegw_can_send(struct socket* can_sock, struct can_frame* cf)
{
- struct can_frame cf;
- struct kvec vec;
struct msghdr mh;
- struct eth_can_gw* job;
- struct hlist_node* pos;
-
- vec.iov_base = &cf;
- vec.iov_len = sizeof(cf);
+ struct kvec vec;
+ int err;
mh.msg_name = NULL;
mh.msg_namelen = 0;
- mh.msg_iov = NULL;
- mh.msg_iovlen = 0;
mh.msg_control = NULL;
mh.msg_controllen = 0;
mh.msg_flags = 0;
- while( 1 )
- {
- if( kthread_should_stop() ) /* up() ?, recv is blocking */
- break;
- kernel_recvmsg( udp_sock, &mh, &vec, 1, sizeof(cf), 0 ); /* todo: handle error */
- printk( "received udp msg_id:%d\n", cf.can_id );
- rcu_read_lock();
- hlist_for_each_entry_rcu( job, pos, ð_can_job, list )
- {
- /* ToDo from filter */
- gw_can_send( &cf, job->dst_if_idx );
- }
- rcu_read_unlock();
- }
+ vec.iov_base = cf;
+ vec.iov_len = sizeof(*cf);
- return 0;
+ err = kernel_sendmsg(can_sock, &mh, &vec, 1, sizeof(*cf));
+
+ return err;
}
-inline static void gw_udp_send( struct can_frame* cf, struct in_addr ipaddr, u16 port )
+/**
+ * cegw_udp2can - performs udp->can routing
+ *
+ * This function is run as a thread.
+ */
+static int cegw_udp2can(void *data)
{
- struct msghdr mh;
- struct sockaddr_in addr;
+ struct can_frame cf;
struct kvec vec;
-
- addr.sin_family = AF_INET;
- addr.sin_port = htons( port );
- addr.sin_addr = ipaddr;
-
- mh.msg_name = &addr;
- mh.msg_namelen = sizeof( addr );
- mh.msg_control = NULL;
- mh.msg_controllen = 0;
- mh.msg_flags = 0;
-
- vec.iov_base = cf;
- vec.iov_len = sizeof( *cf );
-
- kernel_sendmsg( udp_sock, &mh, &vec, 1, sizeof( *cf ) );
-}
+ struct msghdr mh;
+ struct cegw_job *job = (struct cegw_job *)data;
+ struct socket *udp_sock = NULL, *can_sock = NULL;
+ int ret = 0;
+
+ memset(&mh, 0, sizeof(mh));
+ udp_sock = job->udp_sock;
+ can_sock = job->can_sock;
+
+ while (1) {
+ vec.iov_base = &cf;
+ vec.iov_len = sizeof(cf);
+ ret = kernel_recvmsg(udp_sock, &mh, &vec, 1,
+ sizeof(cf), 0);
+ if (ret < 1)
+ break;
-/***********************
- * CAN
- ***********************/
+ cf.can_id = be32_to_cpu(cf.can_id);
+ cegw_can_send(can_sock, &cf);
+ }
+
+ cegw_thread_stop(job);
+ kref_put(&job->refcount, cegw_job_release);
+ do_exit(ret);
+}
-static int gw_can_recv( void* data )
+/**
+ * cegw_can2udp - performs can->udp routing
+ *
+ * This function is run as a thread.
+ */
+static int cegw_can2udp(void* data)
{
struct msghdr mh;
struct kvec vec;
struct can_frame cf;
- struct sockaddr_can ca;
- struct can_eth_gw* job;
- struct hlist_node* pos;
-
- mh.msg_name = &ca;
- mh.msg_namelen = sizeof( ca );
- mh.msg_control = NULL;
- mh.msg_controllen = 0;
- mh.msg_flags = 0;
-
- vec.iov_base = &cf;
- vec.iov_len = sizeof( cf );
+ struct cegw_job* job = (struct cegw_job*)data;
+ struct socket* udp_sock = job->udp_sock;
+ struct socket* can_sock = job->can_sock;
+ int i;
+ int ret;
+
+ memset(&mh, 0, sizeof(mh));
- while( 1 )
- {
- if( kthread_should_stop() ) /**/
+ while (1) {
+ vec.iov_base = &cf;
+ vec.iov_len = sizeof(cf);
+
+ ret = kernel_recvmsg(can_sock, &mh, &vec, 1,
+ sizeof(cf), 0);
+ if (ret < 1)
break;
- kernel_recvmsg( can_sock, &mh, &vec, 1, sizeof( cf ), 0 );
- printk( "received can msg_id:%d, from:%d\n", cf.can_id, ca.can_ifindex );
- rcu_read_lock();
- hlist_for_each_entry_rcu( job, pos, &can_eth_job, list )
- {
- printk( KERN_INFO "%x\n", job->dst_addr );
- if( job->src_if_idx == ca.can_ifindex )
- gw_udp_send( &cf, job->dst_addr, job->dst_port );
+
+ cf.can_id = cpu_to_be32(cf.can_id);
+ for (i=0; i<job->udp_dstcnt; i++) {
+ cegw_udp_send(udp_sock, &cf, &job->udp_dst[i]);
}
- rcu_read_unlock();
}
-
- return 0;
+
+ cegw_thread_stop(job);
+ kref_put(&job->refcount, cegw_job_release);
+ do_exit(ret);
}
-inline static void gw_can_send( struct can_frame* cf, int ifidx )
+static void cegw_job_release(struct kref *ref)
{
- struct msghdr mh;
- struct kvec vec;
- struct sockaddr_can ca =
- {
- .can_family = AF_CAN,
- .can_ifindex = ifidx
- };
-
- mh.msg_name = &ca;
- mh.msg_namelen = sizeof( ca );
- mh.msg_control = NULL;
- mh.msg_controllen = 0;
- mh.msg_flags = 0;
-
- vec.iov_base = cf;
- vec.iov_len = sizeof( *cf );
-
- kernel_sendmsg( can_sock, &mh, &vec, 1, sizeof( *cf ) );
-}
+ struct cegw_job *job = container_of(ref, struct cegw_job, refcount);
-/* NetLink */
+ fput(job->can_sock->file);
+ fput(job->udp_sock->file);
+ kfree(job);
+}
-static int cgw_create_job( struct sk_buff* skb, struct nlmsghdr* nlh,
- void* arg )
+/**
+ * cegw_thread_start - start working threads
+ * @data: (struct cegw_job *) with sockets and udp addresses filled in
+ *
+ * Two threads are started. One is serving udp->can routing and the other
+ * can->udp.
+ */
+static int cegw_thread_start(void *data)
{
- struct nlattr* tb[ CGW_MAX+1 ];
- struct rtcanmsg *r;
- struct cgw_job *gwj;
- struct can_eth_gw* cethgw = NULL;
- struct eth_can_gw* ecangw = NULL;
- int err = 0;
-
- if (nlmsg_len(nlh) < sizeof(*r))
- return -EINVAL;
-
- r = nlmsg_data(nlh);
- if (r->can_family != AF_CAN)
- return -EPFNOSUPPORT;
-
- err = nlmsg_parse( nlh, sizeof( struct rtcanmsg ), tb, CGW_MAX, NULL );
- if( err < 0 )
- {
- printk( KERN_ERR "error: nlmsg_parse\n" );
- return err;
+ struct task_struct *task = NULL;
+ struct cegw_job *job = (struct cegw_job *)data;
+
+ kref_init(&job->refcount);
+ kref_get(&job->refcount);
+
+ task = kthread_run(cegw_udp2can, data, "canethgw_udp2can");
+ if (IS_ERR(task)) {
+ kref_sub(&job->refcount, 2, cegw_job_release);
+ return -ENOMEM;
}
- /* so far we only support CAN -> CAN routings */
- switch( r->gwtype )
- {
- case CGW_TYPE_CAN_ETH_UDP:
- printk( KERN_INFO "can:%d\n", *(int*)nla_data( tb[CGW_CAN_IF] ) );
- printk( KERN_INFO "eth addr:%x\n", *(u32*)nla_data( tb[CGW_ETH_IP] ) );
- printk( KERN_INFO "eth port:%hu\n", *(u16*)nla_data( tb[CGW_ETH_PORT] ) );
- cethgw = kmalloc( sizeof(struct can_eth_gw), GFP_KERNEL );
- if( cethgw == NULL )
- {
- printk( KERN_ERR "error: kmalloc\n" );
- break;
- }
- cethgw->src_if_idx = *(int*)nla_data( tb[CGW_CAN_IF] );
- cethgw->dst_addr = *(struct in_addr*)nla_data( tb[CGW_ETH_IP] );
- cethgw->dst_port = *(u16*)nla_data( tb[CGW_ETH_PORT] );
-
- hlist_add_head_rcu( &cethgw->list, &can_eth_job );
- break;
- case CGW_TYPE_ETH_CAN_UDP:
- printk( KERN_INFO "can:%d\n", *(int*)nla_data( tb[CGW_CAN_IF] ) );
- ecangw = kmalloc( sizeof(struct eth_can_gw), GFP_KERNEL );
- if( ecangw == NULL )
- {
- printk( KERN_ERR "error: kmalloc\n" );
- break;
- }
- ecangw->dst_if_idx = *(int*)nla_data( tb[CGW_CAN_IF] );
- hlist_add_head_rcu( &ecangw->list, ð_can_job );
- break;
- default:
- /* ToDo undef operation */
- break;
+ task = kthread_run(cegw_can2udp, data, "canethgw_can2udp");
+ if (IS_ERR(task)) {
+ cegw_thread_stop(job);
+ kref_put(&job->refcount, cegw_job_release);
+ return -ENOMEM;
}
return 0;
}
-/***********************
- * module init/exit
- ***********************/
-
-static int __init cangw_init( void )
-{
- struct sockaddr_in udp_addr;
- struct sockaddr_can can_addr;
- int ifidx = 0;
-
- /* 1. create can socket and bind to it */
- can_dev = dev_get_by_name( &init_net, "vcan0" ); /* net ns?, release counter! */
- if( can_dev == NULL )
- {
- printk( KERN_ERR "error: vcan0 not found\n" );
- return -1;
+/**
+ * cegw_thread_stop - stops threads
+ */
+static int cegw_thread_stop(struct cegw_job *job)
+{
+ int how = SHUT_RDWR;
+ struct sock *sk = NULL;
+ struct socket *udp_sock = job->udp_sock;
+ struct socket *can_sock = job->can_sock;
+
+ kernel_sock_shutdown(udp_sock, SHUT_RDWR);
+
+ /* PF_CAN sockets do not implement shutdown - do it manualy */
+ sk = can_sock->sk;
+ how++;
+ lock_sock(sk);
+ sk->sk_shutdown |= how;
+ sk->sk_state_change(sk);
+ release_sock(sk);
+
+ return 0;
+}
+
+static int cegw_open(struct inode *inode, struct file *file)
+{
+ file->private_data = NULL;
+
+ if (try_module_get(THIS_MODULE) == false)
+ return -EAGAIN;
+
+ return 0;
+}
+
+static int cegw_release(struct inode *inode, struct file *file)
+{
+ struct cegw_job *job = (struct cegw_job *)file->private_data;
+
+ if (job) {
+ cegw_thread_stop(job);
}
- ifidx = can_dev->ifindex;
- dev_put( can_dev );
-
- if( sock_create_kern( PF_CAN, SOCK_RAW, CAN_RAW, &can_sock) != 0 )
- {
- printk( KERN_ERR "error: can_sock creation failed\n" );
- return -1;
+
+ module_put(THIS_MODULE);
+ return 0;
+}
+
+/**
+ * cegw_ioctl_start - processes ioctl CEGW_IOCTL_START call
+ *
+ * The function takes over cegw_ioctl structure from userspace and
+ * prepares cegw_job structure. The cegw_job is stored in
+ * file->private_data and used by kernel threads to serve gateway
+ * functionality.
+ */
+static long cegw_ioctl_start(struct file *file, unsigned long arg)
+{
+ int i;
+ int err = 0;
+ __u32 dstcnt = 0;
+ __u32 addrlen = 0;
+ struct cegw_ioctl gwctl;
+ struct cegw_job *job = NULL;
+
+ err = copy_from_user(&gwctl, (void __user *)arg, sizeof(gwctl));
+ if (err != 0)
+ return -EFAULT;
+
+ dstcnt = gwctl.udp_dstcnt;
+ addrlen = gwctl.udp_addrlen;
+
+ if (addrlen != sizeof(struct sockaddr_in))
+ return -EAFNOSUPPORT;
+
+ /* */
+ job = kmalloc(GFP_KERNEL, sizeof(*job) + dstcnt*addrlen );
+ if (job == NULL)
+ return -ENOMEM;
+
+ err = copy_from_user(&job->udp_dst, (void __user *)(arg + sizeof(struct cegw_ioctl)), dstcnt*addrlen);
+ if (err != 0) {
+ kfree(job);
+ return -EFAULT;
}
-
- can_addr.can_family = AF_CAN;
- can_addr.can_ifindex = ifidx;
-
- if( can_sock->ops->bind( can_sock, (struct sockaddr*) &can_addr, sizeof(can_addr) ) != 0 )
- {
- printk( KERN_ERR "can_sock bind failed\n" );
- return -1;
+
+ for (i=0; i<dstcnt; i++) {
+ if (job->udp_dst[i].sin_family != AF_INET) {
+ kfree(job);
+ return -EAFNOSUPPORT;
+ }
}
-
- /* 2. create udp socket and bind to it */
- if( sock_create_kern( PF_INET, SOCK_DGRAM, IPPROTO_UDP, &udp_sock ) != 0 )
- {
- printk( "error: udp_sock creation failed\n" );
- sock_release( can_sock );
- return -1;
+
+ job->udp_sock = sockfd_lookup(gwctl.udp_sock, &err);
+ if (job->udp_sock == NULL) {
+ kfree(job);
+ return err;
}
-
- udp_addr.sin_family = AF_INET;
- udp_addr.sin_port = htons( 10501 );
- udp_addr.sin_addr.s_addr = INADDR_ANY;
-
- if( udp_sock->ops->bind( udp_sock, (struct sockaddr*)&udp_addr, sizeof( udp_addr ) ) != 0 ) /* ref impl ?!? */
- {
- printk( "error: binding failed\n" );
- sock_release( udp_sock );
- sock_release( can_sock );
- return -1;
+
+ job->can_sock = sockfd_lookup(gwctl.can_sock, &err);
+ if (job->can_sock == NULL) {
+ fput(job->udp_sock->file);
+ kfree(job);
+ return err;
}
-
- /* 3. subscribe to netlink */
- //if( __rtnl_register( PF_CAN, RTM_GETROUTE, ) != 0 )
- __rtnl_register( PF_CAN, RTM_NEWROUTE, cgw_create_job, NULL, NULL );
- //__rtnl_register( PF_CAN, RTM_DELROUTE, )
-
- /* 4. run threads */
- eth_to_can = kthread_run( gw_udp_recv, NULL, "cangw" );
- can_to_eth = kthread_run( gw_can_recv, NULL, "cangw" );
-
- /*
- if( sock_create_kern( AF_CAN, SOCK_RAW, CAN_RAW, &can_sock ) != 0 )
- {s
- printk( "error: can_sock creation failed\n" );
+
+ job->udp_dstcnt = dstcnt;
+
+ err = cegw_thread_start(job);
+ if (err != 0)
+ return err;
+
+ file->private_data = job;
+ return 0;
+}
+
+static long cegw_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ int err;
+
+ switch (cmd) {
+ case CEGW_IOCTL_START:
+ err = cegw_ioctl_start(file, arg);
+ break;
+ default:
+ err = -EOPNOTSUPP;
+ break;
}
- */
-
+
+ return err;
+}
+
+static const struct file_operations cegw_fops = {
+ .owner = THIS_MODULE,
+ .open = cegw_open,
+ .release = cegw_release,
+ .unlocked_ioctl = cegw_ioctl
+};
+
+static struct miscdevice cegw_device = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "canethgw",
+ .fops = &cegw_fops
+};
+
+static int __init cegw_init(void)
+{
+ misc_register(&cegw_device);
+
return 0;
}
-static void __exit cangw_exit( void )
+static void __exit cegw_exit(void)
{
- sock_release( udp_sock );
- sock_release( can_sock );
-
- printk( "cangw: exit\n" );
- //kthread_stop( ts );
+ misc_deregister(&cegw_device);
+
+ return;
}
-module_init( cangw_init );
-module_exit( cangw_exit );
+module_init(cegw_init);
+module_exit(cegw_exit);
projects / can-eth-gw.git / blobdiff