]> rtime.felk.cvut.cz Git - can-eth-gw.git/blobdiff - kernel/canethgw.c
source code formatted to comply with Linux code style
[can-eth-gw.git] / kernel / canethgw.c
index 3a9b9661ca54d0e71fef3843145d89854453846d..27f752516a41f7c8db854f5a58e78a2d05193ae6 100644 (file)
@@ -1,4 +1,4 @@
-#define DEBUG 1
+#define DEBUG
 
 #include <linux/module.h>
 #include <linux/kernel.h>
@@ -8,7 +8,9 @@
 #include <linux/wait.h>
 #include <linux/netdevice.h>
 #include <linux/socket.h>
+#include <linux/if_arp.h>
 #include <linux/net.h>
+#include <linux/netdevice.h>
 #include <linux/can/core.h>
 #include <linux/can.h>
 #include <net/rtnetlink.h>
 #include <linux/mutex.h>
 #include <net/inet_common.h>
 
-/**
- * ToDo:
- * [ ] encapsule module - check inputs
- * [ ] refactor - chc .h
- * [ ] dump callback
- * [ ] rtnl vs nl functions
- * [ ] stop threads
- * [ ] change listening
- * [ ] clean exit - threads, jobs
- */
-
-MODULE_LICENSE( "GPL" );
-
-static int  cegw_udp_can( void* data );
-inline static void cegw_udp_send( struct socket* udp_sock, struct can_frame* cf, struct in_addr ipaddr, u16 port );
-static int  cegw_can_udp( void* data );
-inline static void cegw_can_send( struct socket* can_sock, struct can_frame* cf, int ifindex );
-static void cegw_thread_start( void );
-static void cegw_thread_stop( void );
-static int  cegw_thread_restart( void* arg );
-
-#define CEGW_STOPPED 0
-#define CEGW_RUNNING 1
+MODULE_LICENSE("GPL");
 
-static struct socket* can_sock, * udp_sock;
-static struct task_struct* eth_to_can, * can_to_eth;
-/* ToDo: protect with mutex */
-static int cegw_state = CEGW_STOPPED;
+static int  cegw_udp_can(void *data);
+static void cegw_udp_send(struct socket *udp_sock, struct can_frame *cf,
+               struct in_addr ipaddr, u16 port);
+static int  cegw_can_udp(void *data);
+static void cegw_can_send(struct socket *can_sock, struct can_frame *cf,
+               int ifindex);
+static int cegw_thread_start(void *data);
+static int cegw_thread_stop(void);
 
-struct can_eth_gw
+enum __cegw_state
 {
-       int src_ifindex;
-       struct in_addr dst_addr;
-       unsigned short dst_port;
-       struct hlist_node list;
+       CEGW_RUN,
+       CEGW_STOP,
+       CEGW_EXIT
 };
 
-struct eth_can_gw
+struct cegw_rule
 {
-       int dst_if_idx;
+       int can_ifindex;
+       struct in_addr eth_ip;
+       unsigned short eth_port;
        struct hlist_node list;
 };
 
-HLIST_HEAD( can_eth_job );
-HLIST_HEAD( eth_can_job );
-
-struct 
+struct cegw_setting
 {
-       struct can_filter filter;
-       int can_idx;
-       /* bind on if */
-       struct in_addr eth_addr;
+       struct in_addr eth_ip;
        unsigned short eth_port;
-} cegw_setting;
+};
+
+static int cegw_state = CEGW_STOP;
+static struct socket *can_sock = NULL, *udp_sock = NULL;
+static struct task_struct *eth_to_can = NULL, *can_to_eth = NULL;
+static struct notifier_block notifier;
 
-DECLARE_COMPLETION( cegw_compl_init );
-DECLARE_COMPLETION( cegw_compl_exit );
-DEFINE_MUTEX( cegw_setting_mutex );
+HLIST_HEAD(rule_can_eth);
+HLIST_HEAD(rule_eth_can);
+DEFINE_MUTEX(cegw_mutex);
 
-inline static void cegw_udp_send( struct socket* udp_sock, struct can_frame* cf, struct in_addr ipaddr, u16 port )
+static void cegw_udp_send(struct socket *udp_sock, struct can_frame *cf,
+               struct in_addr ipaddr, u16 port)
 {
        struct msghdr mh;
        struct sockaddr_in addr;
        struct kvec vec;
-       
+
        addr.sin_family = AF_INET;
-       addr.sin_port = htons( port );
+       addr.sin_port = htons(port);
        addr.sin_addr = ipaddr;
-       
+
        mh.msg_name = &addr;
-       mh.msg_namelen = sizeof( 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 ) );
+       vec.iov_len = sizeof(*cf);
+
+       kernel_sendmsg(udp_sock, &mh, &vec, 1, sizeof(*cf));
 }
 
-inline static void cegw_can_send( struct socket* can_sock, struct can_frame* cf, int ifindex )
+static void cegw_can_send(struct socket* can_sock, struct can_frame* cf,
+               int ifindex)
 {
        struct msghdr mh;
        struct kvec vec;
        struct sockaddr_can addr;
-       
+
        addr.can_family = AF_CAN;
        addr.can_ifindex = ifindex;
-       
+
        mh.msg_name = &addr;
-       mh.msg_namelen = sizeof( 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( can_sock, &mh, &vec, 1, sizeof( *cf ) ); /* ToDo: handle error */
+       vec.iov_len = sizeof(*cf);
+
+       kernel_sendmsg(can_sock, &mh, &vec, 1, sizeof(*cf));
 }
 
-/** 
+/**
  * cegw_udp_can - performs udp->can routing
+ *
  * This function is run as a thread.
  */
-static int cegw_udp_can( void* data )
+static int cegw_udp_can(void *data)
 {
        struct can_frame cf;
        struct kvec vec;
        struct msghdr mh;
-       struct eth_can_gw* job;
+       struct cegw_rule* rule;
        struct hlist_node* pos;
        int can_ifidx;
        int recv_size;
-       struct sockaddr_in udp_addr;
-       struct sockaddr_can can_addr;
-
-       can_addr.can_family = AF_CAN;
-       can_addr.can_ifindex = 0;
-       
-       udp_addr.sin_family = AF_INET;
-       mutex_lock( &cegw_setting_mutex );
-       udp_addr.sin_port = htons( cegw_setting.eth_port );
-       udp_addr.sin_addr = cegw_setting.eth_addr;
-       mutex_unlock( &cegw_setting_mutex );
 
        mh.msg_name = NULL;
        mh.msg_namelen = 0;
@@ -153,419 +129,491 @@ static int cegw_udp_can( void* data )
        mh.msg_controllen = 0;
        mh.msg_flags = 0;
 
-       if( sock_create_kern( PF_INET, SOCK_DGRAM, IPPROTO_UDP, &udp_sock) != 0 )
-       {
-               printk( KERN_ERR "canethgw: udp socket creation failed\n" );
-               return -1;
-       }
-
-       if( sock_create_kern( PF_CAN, SOCK_RAW, CAN_RAW, &can_sock) != 0 )
-       {
-               printk( KERN_ERR "canethgw: can socket creation failed\n" );
-               return -1;
-       }
-
-       if( kernel_bind( udp_sock, (struct sockaddr*)&udp_addr, sizeof( udp_addr ) ) != 0 )
-       {
-               printk( KERN_ERR "canethgw: udp socket binding failed\n" );
-               sock_release( udp_sock );
-               sock_release( can_sock );
-               return -1;
-       }
-
-       if( kernel_bind( can_sock, (struct sockaddr*) &can_addr, sizeof(can_addr) ) != 0 )
-       {
-               printk( KERN_ERR "canethgw: can socket binding failed\n" );
-               sock_release( udp_sock );
-               sock_release( can_sock );
-               return -1;
-       }
-
-       pr_devel( "canethgw: cegw_udp_can init complete\n" );
-       complete_all( &cegw_compl_init ); /* ToDo: why _all? */
-       pr_devel( "canethgw: cegw_udp_can is entering working cycle\n" );
-
-       while( 1 )
-       {
-               if( cegw_state == CEGW_STOPPED )
+       while (1) {
+               if (cegw_state == CEGW_STOP)
                        break;
                vec.iov_base = &cf;
                vec.iov_len = sizeof(cf);
-               recv_size = kernel_recvmsg( udp_sock, &mh, &vec, 1, sizeof(cf), 0 ); /* ToDo: handle error, size check */
-               if( recv_size == 0 )
-               {
+               recv_size = kernel_recvmsg(udp_sock, &mh, &vec, 1, 
+                               sizeof(cf), 0);
+               /* recv_size == 0 when shutting down */
+               if (recv_size != sizeof(cf) || recv_size == 0)
                        continue;
-               }
-               hlist_for_each_entry_rcu( job, pos, &eth_can_job, list )
-               {
-                       rcu_read_lock(); /**/
-                       can_ifidx = job->dst_if_idx;
+               else if (recv_size < 0)
+                       return -1;
+
+               hlist_for_each_entry_rcu(rule, pos, &rule_eth_can, list) {
+                       rcu_read_lock();
+                       can_ifidx = rule->can_ifindex;
                        rcu_read_unlock();
                        /* ToDo: from filter */
-                       cegw_can_send( can_sock, &cf, can_ifidx );
+                       cegw_can_send(can_sock, &cf, can_ifidx);
                }
        }
 
-       pr_devel( "canethgw: cegw_udp_can is ready for termination\n" );
-       wait_for_completion( &cegw_compl_exit );
-       sock_release( udp_sock );
-       sock_release( can_sock );
-       cegw_state = CEGW_STOPPED;  /* ToDo */
-       pr_devel( "canethgw: cegw_udp_can terminates\n" );
        return 0;
 }
 
 /**
  * cegw_can_udp - performs can->udp routing
  */
-static int cegw_can_udp( void* data )
+static int cegw_can_udp(void* data)
 {
        struct msghdr mh;
        struct kvec vec;
        struct can_frame cf;
        struct sockaddr_can ca;
-       struct can_eth_gw* job;
+       struct cegw_rule* rule;
        struct hlist_node* pos;
-       struct in_addr eth_addr;
+       struct in_addr eth_ip;
        u16 eth_port;
        int recv_size;
 
        mh.msg_name = &ca;
-       mh.msg_namelen = sizeof( ca );
+       mh.msg_namelen = sizeof(ca);
        mh.msg_control = NULL;
        mh.msg_controllen = 0;
        mh.msg_flags = 0;
 
-       wait_for_completion( &cegw_compl_init );
-       pr_devel( "canethgw: cegw_can_udp is entering working cycle\n" );
-
-       while( 1 )
-       {
-               if( cegw_state == CEGW_STOPPED ) /**/
+       while (1) {
+               if (cegw_state == CEGW_STOP)
                        break;
                vec.iov_base = &cf;
-               vec.iov_len = sizeof( cf );
+               vec.iov_len = sizeof(cf);
 
-               recv_size = kernel_recvmsg( can_sock, &mh, &vec, 1, sizeof( cf ), 0 );
-               if( recv_size == 0 )
-               {
+               recv_size = kernel_recvmsg(can_sock, &mh, &vec, 1,
+                                          sizeof(cf), 0);
+               if (recv_size != sizeof(cf) || recv_size == 0)
                        continue;
-               }
-               hlist_for_each_entry_rcu( job, pos, &can_eth_job, list )
-               {
+               else if (recv_size < 0)
+                       return -1;
+
+               hlist_for_each_entry_rcu(rule, pos, &rule_can_eth, list) {
                        rcu_read_lock();
-                       eth_addr = job->dst_addr;
-                       eth_port = job->dst_port;
+                       eth_ip = rule->eth_ip;
+                       eth_port = rule->eth_port;
                        rcu_read_unlock();
-                       if( job->src_ifindex == ca.can_ifindex )
-                               cegw_udp_send( udp_sock, &cf, eth_addr, eth_port );
+                       if (rule->can_ifindex == ca.can_ifindex)
+                               cegw_udp_send(udp_sock, &cf, eth_ip, eth_port);
                }
        }
-       
-       complete_all( &cegw_compl_exit );
-       pr_devel( "canethgw: cegw_can_udp terminates\n" ); 
+
        return 0;
 }
 
-/* NetLink */
-
-static int cegw_create_job( struct sk_buff* skb, struct nlmsghdr* nlh, void* arg )
+static int cegw_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
        struct nlattr* tb[ CEGW_MAX+1 ];
-       struct can_eth_gw* cethgw = NULL;
-       struct eth_can_gw* ecangw = NULL;
+       struct cegw_rule* rule = NULL;
        int ifindex;
-       u32 ip;
-       u16 port;
+       struct rtmsg* r;
+       struct in_addr ip;
+       unsigned short port;
+       struct cegw_setting* set;
        int err = 0;
-       
-       /* ToDo: size check
+
        if (nlmsg_len(nlh) < sizeof(*r))
                return -EINVAL;
-       */
 
-       err = nlmsg_parse( nlh, sizeof( struct rtmsg ), tb, CEGW_MAX, NULL );
-       if( err < 0 )
-       {
-               printk( KERN_ERR "canethgw: nlmsg_parse error\n" );
+       r = nlmsg_data(nlh);
+
+       if (r->rtm_family != AF_CAN)
+               return -EPFNOSUPPORT;
+
+       err = nlmsg_parse(nlh, sizeof(*r), tb, CEGW_MAX, NULL);
+       if (err < 0) {
+               pr_devel("canethgw: nlmsg_parse error\n");
                return err;
        }
 
-       if( tb[CEGW_CMD_INFO] == NULL )
-       {
-               printk( KERN_ERR "canethgw: bad cmd error\n" );
+       if (tb[CEGW_CMD_INFO] == NULL) {
+               pr_devel("canethgw: CEGW_CMD_INFO is missing in rtmsg\n");
                return -EINVAL;
        }
 
-       switch( *(int*)nla_data( tb[CEGW_CMD_INFO] ) )
-       {
-               case CEGW_LISTEN:
-                       if( cegw_state == CEGW_RUNNING )
-                       {
-                               mutex_lock( &cegw_setting_mutex );
-                               cegw_setting.eth_addr = *(struct in_addr*)nla_data( tb[CEGW_ETH_IP] );
-                               cegw_setting.eth_port = *(u16*)nla_data( tb[CEGW_ETH_PORT] );
-                               mutex_unlock( &cegw_setting_mutex );
-                               kthread_run( cegw_thread_restart, NULL, "canethgw" );
-                       } else
-                       {
-                               mutex_lock( &cegw_setting_mutex );
-                               cegw_setting.eth_addr = *(struct in_addr*)nla_data( tb[CEGW_ETH_IP] );
-                               cegw_setting.eth_port = *(u16*)nla_data( tb[CEGW_ETH_PORT] );
-                               mutex_unlock( &cegw_setting_mutex );
-                               cegw_thread_start();
-                       }
-                       break;
-               case CEGW_RULE_CAN_ETH: /* new can->eth rule */
-               {
-                       ifindex = *(int*)nla_data( tb[CEGW_CAN_IFINDEX] );
-                       ip = *(u32*)nla_data( tb[CEGW_ETH_IP] );
-                       port = *(u16*)nla_data( tb[CEGW_ETH_PORT] );
-                       pr_devel( "canethgw: new can->eth rule - (%d)->(%x:%hu)\n", ifindex, ip, port );
-
-                       cethgw = kmalloc( sizeof(struct can_eth_gw), GFP_KERNEL );
-                       if( cethgw == NULL )
-                       {
-                               break;
-                       }
-                       cethgw->src_ifindex = ifindex;
-                       cethgw->dst_addr = *(struct in_addr*)nla_data( tb[CEGW_ETH_IP] );
-                       cethgw->dst_port = *(u16*)nla_data( tb[CEGW_ETH_PORT] );
-                       
-                       hlist_add_head_rcu( &cethgw->list, &can_eth_job );
+       switch (*(int*)nla_data(tb[CEGW_CMD_INFO])) {
+       case CEGW_LISTEN:
+               if (!tb[CEGW_ETH_IP] || !tb[CEGW_ETH_PORT]) {
+                       pr_devel("canethgw: missing attribute for CEGW_LISTEN\n");
+                       return -EINVAL;
                }
+
+               /* ToDo: valid listen address */
+               set = kmalloc(sizeof(*set), GFP_KERNEL);
+               if (set == NULL)
+                       return -ENOMEM;
+               set->eth_ip   = *(struct in_addr*)nla_data(tb[CEGW_ETH_IP]);
+               set->eth_port = *(unsigned short*)nla_data(tb[CEGW_ETH_PORT]);
+               kthread_run(cegw_thread_start, set, "canethgw");
+               break;
+       case CEGW_RULE_CAN_ETH:
+               if (!tb[CEGW_ETH_IP] || !tb[CEGW_ETH_PORT] || 
+                   !tb[CEGW_CAN_IFINDEX]) {
+                       pr_devel("canethgw: missing attribute for "
+                                "CEGW_RULE_CAN_ETH\n");
+                       return -EINVAL;
+               }
+
+               ifindex = *(int*)nla_data(tb[CEGW_CAN_IFINDEX]);
+               ip = *(struct in_addr*)nla_data(tb[CEGW_ETH_IP]);
+               port = *(unsigned short*)nla_data(tb[CEGW_ETH_PORT]);
+               pr_devel("canethgw: new can->eth rule - (%d)->(%x:%hu)\n",
+                        ifindex, ip.s_addr, port);
+
+               rule = kmalloc(sizeof(struct cegw_rule), GFP_KERNEL);
+               if (rule == NULL)
+                       return -ENOMEM;
+
+               rule->can_ifindex = ifindex;
+               rule->eth_ip = ip;
+               rule->eth_port = port;
+
+               hlist_add_head_rcu(&rule->list, &rule_can_eth);
+               break;
+       case CEGW_RULE_ETH_CAN:
+               if (!tb[CEGW_ETH_IP] || !tb[CEGW_ETH_PORT] || 
+                   !tb[CEGW_CAN_IFINDEX]) {
+                       pr_devel("canethgw: missing attribute for"
+                                "CEGW_RULE_ETH_CAN\n");
+                       return -EINVAL;
+               }
+
+               ifindex = *(int*)nla_data(tb[CEGW_CAN_IFINDEX]);
+               ip = *(struct in_addr*)nla_data(tb[CEGW_ETH_IP]);
+               port = *(unsigned short*)nla_data(tb[CEGW_ETH_PORT]);
+               pr_devel("canethgw: new eth->can rule - (%x:%hu)->(%d)\n",
+                        ip.s_addr, port, ifindex);
+
+               rule = kmalloc(sizeof(struct cegw_rule), GFP_KERNEL);
+               if (rule == NULL)
+                       return -ENOMEM;
+
+               rule->can_ifindex = ifindex;
+               rule->eth_ip = ip;
+               rule->eth_port = port;
+
+               hlist_add_head_rcu(&rule->list, &rule_eth_can);
+               break;
+       default:
+               pr_devel("canethgw: unknown CEGW_CMD_INFO\n");
                break;
-               case CEGW_RULE_ETH_CAN: /* new eth->can rule */
-                       printk( KERN_INFO "can:%d\n", *(int*)nla_data( tb[CEGW_CAN_IFINDEX] ) );
-                       ecangw = kmalloc( sizeof(struct eth_can_gw), GFP_KERNEL );
-                       if( ecangw == NULL )
-                       {
-                               break;
-                       }
-                       ecangw->dst_if_idx = *(int*)nla_data( tb[CEGW_CAN_IFINDEX] );
-                       hlist_add_head_rcu( &ecangw->list, &eth_can_job );
-                       break;
-               default:
-                       pr_devel( "canethgw: unknown CEGW_CMD_INFO\n" );
-                       /* ToDo undef operation */
-                       break;
        }
 
        return 0;
 }
 
-static int cegw_remove_job( struct sk_buff* skb, struct nlmsghdr* nlh, void* arg )
+static void cegw_flush(void)
 {
-       struct rtmsg* r;
-       struct nlattr* tb[ CEGW_MAX+1 ];
-       struct hlist_node* pos,* n;
-       struct can_eth_gw* ceth;
-       struct eth_can_gw* ecan;
+       struct cegw_rule *rule;
+       struct hlist_node *pos, *n;
+
+       hlist_for_each_entry_safe(rule, pos, n, &rule_can_eth, list) {
+               hlist_del(&rule->list);
+               kfree(rule);
+       }
+       hlist_for_each_entry_safe(rule, pos, n, &rule_eth_can, list) {
+               hlist_del(&rule->list);
+               kfree(rule);
+       }
+}
 
+static int cegw_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
+{
+       struct rtmsg *r;
+       struct nlattr *tb[CEGW_MAX+1];
        int err = 0;
 
-       if( nlmsg_len(nlh) < sizeof(*r) )
+       if (nlmsg_len(nlh) < sizeof(*r))
                return -EINVAL;
-       
-       r = nlmsg_data( nlh );
 
-       if( r->rtm_family != AF_CAN )
+       r = nlmsg_data(nlh);
+
+       if (r->rtm_family != AF_CAN)
                return -EPFNOSUPPORT;
 
-       /*
-       if( r->gwtype != CGW_TYPE_CAN_ETH_UDP )
+       err = nlmsg_parse(nlh, sizeof(struct rtmsg), tb, CEGW_MAX, NULL);
+       if (err != 0)
                return -EINVAL;
-       */
-       printk( "attrsize=%d\n", nlmsg_attrlen(nlh, sizeof(struct rtmsg)) );
 
-       err = nlmsg_parse( nlh, sizeof(struct rtmsg), tb, CEGW_MAX, NULL );
-       if( err != 0 )
+       if (tb[CEGW_CMD_INFO] == NULL) {
+               pr_devel("canethgw: CEGW_CMD_INFO is missing in rtmsg\n");
                return -EINVAL;
+       }
 
-       if( tb[CEGW_CMD_INFO] == NULL )
+       if (*(int*)nla_data(tb[CEGW_CMD_INFO]) != CEGW_FLUSH) {
                return -EINVAL;
-       
-       if( *(int*)nla_data( tb[CEGW_CMD_INFO] ) == CEGW_FLUSH )
-       {
-               hlist_for_each_entry_safe( ceth, pos, n, &can_eth_job, list )
-               {
-                       hlist_del( &ceth->list );
-                       kfree( ceth );
-               }
-               hlist_for_each_entry_safe( ecan, pos, n, &eth_can_job, list )
-               {
-                       hlist_del( &ecan->list );
-                       kfree( ecan );
-               }
        }
-       //      tb[]
+
+       cegw_flush();
+
        return 0;
 }
 
-static int cegw_dump_job( struct sk_buff* skb, struct netlink_callback* cb )
+static int cegw_put_rule(struct sk_buff *skb, int type, struct cegw_rule *rule)
 {
-       struct can_eth_gw* ceth;
-       struct eth_can_gw* ecan;
-       struct hlist_node* pos;
-       struct nlmsghdr* nlh;
-       int idx = 0;
-       int s_idx = cb->args[0];
-       int ifidx, type;
-       struct in_addr dst_ip; 
-       unsigned short dst_port;
+       int ifindex;
+       struct in_addr ip;
+       unsigned short port;
+       struct nlmsghdr *nlh;
+
+       ifindex = rule->can_ifindex;
+       ip = rule->eth_ip;
+       port = rule->eth_port;
+
+       nlh = nlmsg_put(skb, 0, 0, 0, 0, 0);
+       if (nlh == NULL)
+               return -EMSGSIZE;
+
+       /* type */
+       if (nla_put(skb, CEGW_TYPE, sizeof(type), &type) < 0)
+               goto cancel;
+       else
+               nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(type));
+
+       /* can ifindex */
+       if (nla_put(skb, CEGW_CAN_IFINDEX, sizeof(ifindex), &ifindex) < 0)
+               goto cancel;
+       else
+               nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(ifindex));
+
+       /* ip adress */
+       if (nla_put(skb, CEGW_ETH_IP, sizeof(ip), &ip) < 0)
+               goto cancel;
+       else
+               nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(ip));
+
+       /* port */
+       if (nla_put(skb, CEGW_ETH_PORT, sizeof(port), &port) < 0)
+               goto cancel;
+       else
+               nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(port));
 
-       rcu_read_lock();
-       hlist_for_each_entry_rcu( ecan, pos, &eth_can_job, list )
-       {
+       return skb->len;
 
-       //      if( idx < s_idx )
-       //              goto cont1;
+cancel:
+       nlmsg_cancel(skb, nlh);
+       return -EMSGSIZE;
+}
 
-               nlh = nlmsg_put( skb, 0, 0, 0, 0, 0 );
+static int cegw_getroute(struct sk_buff *skb, struct netlink_callback *cb)
+{
+       struct cegw_rule *rule;
+       struct hlist_node *pos;
+       int idx = 0;
+       int s_idx = cb->args[0];
 
-               ifidx = ecan->dst_if_idx;
-               type = CEGW_RULE_ETH_CAN;
-               nla_put( skb, CEGW_TYPE, sizeof(type), &type );
-               nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN( sizeof(type) );
+       rcu_read_lock();
+       hlist_for_each_entry_rcu(rule, pos, &rule_eth_can, list) {
+               if (idx < s_idx)
+                       goto cont1;
 
-               nla_put( skb, CEGW_CAN_IFINDEX, sizeof(ifidx), &ifidx ); /* ToDo return */
-               nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN( sizeof(ifidx) );
+               if (cegw_put_rule(skb, CEGW_RULE_ETH_CAN, rule) < 0)
+                       goto brk;
 cont1:
                idx++;
        }
-       rcu_read_unlock();
 
-       rcu_read_lock();
-       hlist_for_each_entry_rcu( ceth, pos, &can_eth_job, list )
-       {
-       //      if( idx < s_idx )
-       //              goto cont2;
-       
-               nlh = nlmsg_put( skb, 0, 0, 0, 0, 0 );
-
-               ifidx = ceth->src_ifindex;
-               type = CEGW_RULE_CAN_ETH;
-               dst_ip = ceth->dst_addr;
-               dst_port = ceth->dst_port;
-
-               nla_put( skb, CEGW_TYPE, sizeof(type), &type );
-               nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN( sizeof(type) );
-
-               nla_put( skb, CEGW_CAN_IFINDEX, sizeof(ifidx), &ifidx ); /* ToDo return */
-               nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN( sizeof(ifidx) );
-
-               nla_put( skb, CEGW_ETH_IP, sizeof(dst_ip), &dst_ip ); /* ToDo return */
-               nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN( sizeof(dst_ip) );
-
-               nla_put( skb, CEGW_ETH_PORT, sizeof(dst_port), &dst_port ); /* ToDo return */
-               nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN( sizeof(dst_port) );
-       
-               //nla_put( skb, CGW_ETH_IP, sizeof() IP_ADDR  )
+       hlist_for_each_entry_rcu(rule, pos, &rule_can_eth, list) {
+               if (idx < s_idx)
+                       goto cont2;
+
+               if (cegw_put_rule(skb, CEGW_RULE_CAN_ETH, rule) < 0)
+                       goto brk;
 cont2:
                idx++;
        }
-       rcu_read_unlock();
 
-       /* ToDo nlmsg_cancel */
+brk:
+       rcu_read_unlock();
        cb->args[0] = idx;
 
        return skb->len;
 }
 
-static void cegw_thread_start( void )
+static int cegw_notifier(struct notifier_block *nb, unsigned long msg, void *data)
+{
+       struct net_device *dev = (struct net_device *)data;
+       struct cegw_rule *rule;
+       struct hlist_node *pos, *n;
+
+       if (!net_eq(dev_net(dev), &init_net))
+               return NOTIFY_DONE;
+       if (dev->type != ARPHRD_CAN)
+               return NOTIFY_DONE;
+
+       if (msg == NETDEV_UNREGISTER) {
+               hlist_for_each_entry_safe(rule, pos, n, &rule_eth_can, list) {
+                       if (rule->can_ifindex == dev->ifindex) {
+                               hlist_del(&rule->list);
+                               kfree(rule);
+                       }
+               }
+
+               hlist_for_each_entry_safe(rule, pos, n, &rule_can_eth, list) {
+                       if (rule->can_ifindex == dev->ifindex) {
+                               hlist_del(&rule->list);
+                               kfree(rule);
+                       }
+               }
+       }
+
+       return NOTIFY_DONE;
+}
+
+/**
+ * cegw_thread_start - start working threads
+ * @data: (struct cegw_setting *) with new listening address
+ *
+ * Two threads are started. One is serving udp->can routing and the other
+ * can->udp.
+ */
+static int cegw_thread_start(void *data)
 {
-       cegw_state = CEGW_RUNNING;
-
-       INIT_COMPLETION( cegw_compl_init );
-       INIT_COMPLETION( cegw_compl_exit );
-       
-       eth_to_can = kthread_create( cegw_udp_can, NULL, "canethgw" );
-       if( !IS_ERR( eth_to_can ) )
-       { 
-               get_task_struct( eth_to_can );
-               wake_up_process( eth_to_can );
+       struct sockaddr_in udp_addr;
+       struct sockaddr_can can_addr;
+       struct cegw_setting *set;
+
+       set = (struct cegw_setting *)data;
+
+       can_addr.can_family = AF_CAN;
+       can_addr.can_ifindex = 0;
+
+       udp_addr.sin_family = AF_INET;
+       udp_addr.sin_port = htons(set->eth_port);
+       udp_addr.sin_addr = set->eth_ip;
+
+       kfree(data);
+       mutex_lock(&cegw_mutex);
+       if (cegw_state == CEGW_EXIT)
+               return -1;
+       /* stops threads if exist */
+       cegw_thread_stop();
+
+       /* create and bind sockets */
+       if (sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &udp_sock)
+           != 0) {
+               printk(KERN_ERR "canethgw: udp socket creation failed\n");
+               return -1;
+       }
+
+       if (sock_create_kern(PF_CAN, SOCK_RAW, CAN_RAW, &can_sock) != 0) {
+               printk(KERN_ERR "canethgw: can socket creation failed\n");
+               return -1;
+       }
+
+       if (kernel_bind(udp_sock, (struct sockaddr*)&udp_addr,
+                       sizeof(udp_addr)) != 0) {
+               printk(KERN_ERR "canethgw: udp socket binding failed\n");
+               sock_release(udp_sock);
+               sock_release(can_sock);
+               return -1;
+       }
+
+       if (kernel_bind(can_sock, (struct sockaddr*) &can_addr,
+                       sizeof(can_addr)) != 0) {
+               printk(KERN_ERR "canethgw: can socket binding failed\n");
+               kernel_sock_shutdown(udp_sock, SHUT_RDWR);
+               sock_release(udp_sock);
+               sock_release(can_sock);
+               return -1;
+       }
+
+       /* start threads */
+       cegw_state = CEGW_RUN;
+
+       eth_to_can = kthread_create(cegw_udp_can, NULL, "canethgw");
+       if (IS_ERR(eth_to_can)) {
+               cegw_state = CEGW_STOP;
+               sock_release(udp_sock);
+               sock_release(can_sock);
+               return -1;
        }
-       can_to_eth = kthread_run( cegw_can_udp, NULL, "canethgw" );
-       if( !IS_ERR( can_to_eth ) )
-       {
-               get_task_struct( can_to_eth );
-               wake_up_process( can_to_eth );
+       get_task_struct(eth_to_can);
+       wake_up_process(eth_to_can);
+
+       can_to_eth = kthread_create(cegw_can_udp, NULL, "canethgw");
+       if (IS_ERR(can_to_eth)) {
+               cegw_state = CEGW_STOP;
+               kernel_sock_shutdown(udp_sock, SHUT_RDWR);
+               kthread_stop(eth_to_can);
+               sock_release(udp_sock);
+               sock_release(can_sock);
+               return -1;
        }
-       
-       /* ToDo: kthread creation fail */
-       printk( KERN_INFO "threads are running\n" );
+       get_task_struct(can_to_eth);
+       wake_up_process(can_to_eth);
+
+       mutex_unlock(&cegw_mutex);
+       pr_devel("threads are running\n");
+       return 0;
 }
 
-/* ToDo: stop when no threads started */
-static void cegw_thread_stop( void )
+/**
+ * cegw_thread_stop - stops threads and wait for exit
+ *
+ * Waits for threads to stop. Does nothing if cegw_state == CEGW_STOP.
+ */
+static int cegw_thread_stop(void)
 {
        int how = SHUT_RDWR;
-       struct socksk = NULL;
+       struct sock *sk = NULL;
 
-       /* be sure sockets exist */
-       wait_for_completion( &cegw_compl_init );
-       cegw_state = CEGW_STOPPED;
+       if (cegw_state == CEGW_STOP)
+               return 0;
 
+       cegw_state = CEGW_STOP;
        /* shut down socket */
        sk = can_sock->sk;
        how++;
-       lock_sock( sk );
+       lock_sock(sk);
        sk->sk_shutdown |= how;
-       sk->sk_state_change( sk );
-       release_sock( sk );
+       sk->sk_state_change(sk);
+       release_sock(sk);
 
-       kernel_sock_shutdown( udp_sock, SHUT_RDWR );
+       kernel_sock_shutdown(udp_sock, SHUT_RDWR);
 
        /* wait for return to reuse port if restart */
-       kthread_stop( eth_to_can );
-       kthread_stop( can_to_eth );
-}
-
-/**
- * cegw_thread_restart
- */
-static int cegw_thread_restart( void* data )
-{
-       printk( "restart\n" );
-
-       cegw_thread_stop();
-       cegw_thread_start();
+       kthread_stop(eth_to_can);
+       kthread_stop(can_to_eth);
+       sock_release(udp_sock);
+       sock_release(can_sock);
+       can_to_eth = NULL;
+       eth_to_can = NULL;
 
        return 0;
 }
 
-/***********************
- *   module init/exit
- ***********************/
-
-static int __init cangw_init( void )
+static int __init cegw_init(void)
 {
+       notifier.notifier_call = cegw_notifier;
+       register_netdevice_notifier(&notifier);
+
        /* subscribe to netlink */
-       if( __rtnl_register( PF_CAN, RTM_GETROUTE, NULL, cegw_dump_job, NULL ) != 0 )
-       {
-               printk( KERN_ERR "error: rtnl_register fail\n" );
-               return -1;
-       }
-       __rtnl_register( PF_CAN, RTM_NEWROUTE, cegw_create_job, NULL, NULL );
-       __rtnl_register( PF_CAN, RTM_DELROUTE, cegw_remove_job, NULL, NULL );
+       rtnl_register(PF_CAN, RTM_GETROUTE, NULL, cegw_getroute, NULL);
+       rtnl_register(PF_CAN, RTM_NEWROUTE, cegw_newroute, NULL, NULL);
+       rtnl_register(PF_CAN, RTM_DELROUTE, cegw_delroute, NULL, NULL);
 
        return 0;
 }
 
-static void __exit cangw_exit( void )
+static void __exit cegw_exit(void)
 {
-       if( cegw_state == CEGW_RUNNING )
-       {
-               cegw_thread_stop();
-               /* ToDo: frees mem_cache?    */
-               /*       udp must not exists */
-       }
+       /* ToDo: effect on cangw? */
+       rtnl_unregister_all(PF_CAN);
+
+       /* wait for rtnl callbacks */
+       rtnl_lock();
+       rtnl_unlock();
+
+       mutex_lock(&cegw_mutex);
+       cegw_thread_stop();
+       cegw_state = CEGW_EXIT;
+       mutex_unlock(&cegw_mutex);
 
-       /* ToDo: unregister netlink 
-        *       free jobs          */
-       printk( "cangw: exit\n" );
+       unregister_netdevice_notifier(&notifier);
+       cegw_flush();
 }
 
-module_init( cangw_init );
-module_exit( cangw_exit );
+module_init(cegw_init);
+module_exit(cegw_exit);