kernel/canethgw accepts configuration over netlink

The module accepts routing commands from cegw using netlink.
It builds RCU hlist of routing rules and performs routing on
received packets on both CAN and UDP.

diff --git a/kernel/canethgw.c b/kernel/canethgw.c
index 6c02f15d1ea608b4209b6a77e2174bc6e19030b9..0beb89f2d30ba15c867bffbd79d32376c27f2e8e 100644 (file)
--- a/kernel/canethgw.c
+++ b/kernel/canethgw.c
@@ -21,24 +21,23 @@ static struct socket* udp_sock;
 static struct socket* can_sock;
 static struct net_device* can_dev;
 
-struct can_can_gw {
-       struct can_filter filter;
-       int src_idx;
-       int dst_idx;
-};
-
 struct can_eth_gw
 {
-       int src_if_index;
+       int src_if_idx;
        struct in_addr dst_addr;
        unsigned short dst_port;
+       struct hlist_node list;
 };
 
 struct eth_can_gw
 {
-       int dst_if;
+       int dst_if_idx;
+       struct hlist_node list;
 };
 
+HLIST_HEAD( can_eth_job );
+HLIST_HEAD( eth_can_job );
+
 struct cegw_setting
 {
        struct can_filter filter;
@@ -48,27 +47,6 @@ struct cegw_setting
        unsigned short dst_port;
 };
 
-/* list entry for CAN gateways jobs */
-struct cgw_job {
-       struct hlist_node list;
-       struct rcu_head rcu;
-       u32 handled_frames;
-       u32 dropped_frames;
-       union {
-               /* CAN frame data source */
-               struct net_device *dev;
-       } src;
-       union {
-               /* CAN frame data destination */
-               struct net_device *dev;
-       } dst;
-       union {
-               struct can_can_gw ccgw;
-               /* tbc */
-       };
-       u8 gwtype;
-       u16 flags;
-};
 /***********************
  *   UDP
  ***********************/
@@ -78,6 +56,8 @@ static int gw_udp_recv( void* data )
        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);
@@ -96,21 +76,27 @@ static int gw_udp_recv( void* data )
                        break;
                kernel_recvmsg( udp_sock, &mh, &vec, 1, sizeof(cf), 0 ); /* todo: handle error */
                printk( "received udp msg_id:%d\n", cf.can_id );
-               gw_can_send( &cf );
+               rcu_read_lock();
+               hlist_for_each_entry_rcu( job, pos, &eth_can_job, list )
+               {
+                       /* ToDo from filter */
+                       gw_can_send( &cf, job->dst_if_idx );
+               }
+               rcu_read_unlock();
        }
 
        return 0;
 }
 
-static void gw_udp_send( struct can_frame* cf )
+inline static void gw_udp_send( 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( 10502 );
-       addr.sin_addr.s_addr = 0x0100007f;
+       addr.sin_port = htons( port );
+       addr.sin_addr = ipaddr;
        
        mh.msg_name = &addr;
        mh.msg_namelen = sizeof( addr );
@@ -133,35 +119,50 @@ static int gw_can_recv( 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 = NULL;
-       mh.msg_namelen = 0;
+       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 );
-       
+
        while( 1 )
        {
                if( kthread_should_stop() ) /**/
                        break;
                kernel_recvmsg( can_sock, &mh, &vec, 1, sizeof( cf ), 0 );
-               printk( "received can msg_id:%d\n", cf.can_id );
-               gw_udp_send( &cf );
+               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 );
+               }
+               rcu_read_unlock();
        }
        
        return 0;
 }
 
-static void gw_can_send( struct can_frame* cf )
+inline static void gw_can_send( struct can_frame* cf, int ifidx )
 {
        struct msghdr mh;
-       struct kvec vec;        
+       struct kvec vec;
+       struct sockaddr_can ca =
+       {
+               .can_family = AF_CAN,
+               .can_ifindex = ifidx
+       };
        
-       mh.msg_name = NULL;
-       mh.msg_namelen = 0;
+       mh.msg_name = &ca;
+       mh.msg_namelen = sizeof( ca );
        mh.msg_control = NULL;
        mh.msg_controllen = 0;
        mh.msg_flags = 0;
@@ -172,7 +173,7 @@ static void gw_can_send( struct can_frame* cf )
        kernel_sendmsg( can_sock, &mh, &vec, 1, sizeof( *cf ) );
 }
 
-/**/
+/* NetLink */
 
 static int cgw_create_job( struct sk_buff* skb, struct nlmsghdr* nlh,
                      void* arg )
@@ -180,28 +181,58 @@ static int cgw_create_job( struct sk_buff* skb, struct nlmsghdr* nlh,
        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;
  
-       /* so far we only support CAN -> CAN routings */
-       if (r->gwtype == CGW_TYPE_CAN_ETH_UDP)
-               printk( KERN_INFO "canethgw: TYPE_CAN_ETH" );
-       else
-               return -1;
-               
        err = nlmsg_parse( nlh, sizeof( struct rtcanmsg ), tb, CGW_MAX, NULL );
        if( err < 0 )
+       {
+               printk( KERN_ERR "error: nlmsg_parse\n" );
                return err;
+       }
 
-       printk( KERN_INFO "can:%d\n", *(u16*)nla_data( tb[CGW_CAN_IF] ) );
-       printk( KERN_INFO "eth addr:%x\n", *(u16*)nla_data( tb[CGW_ETH_IP] ) );
-       printk( KERN_INFO "eth port:%hu\n", *(u16*)nla_data( tb[CGW_ETH_PORT] ) );
+       /* 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, &eth_can_job );
+                       break;
+               default:
+                       /* ToDo undef operation */
+                       break;
+       }
 
        return 0;
 }
@@ -291,3 +322,4 @@ static void __exit cangw_exit( void )
 
 module_init( cangw_init );
 module_exit( cangw_exit );
+

diff --git a/kernel/canethgw.h b/kernel/canethgw.h
index 1ff2edc27aefe536df5acb32d5bb353b28091842..5acb34b52db16f3c17230e59b071edcdceb4b06f 100644 (file)
--- a/kernel/canethgw.h
+++ b/kernel/canethgw.h
@@ -1,4 +1,4 @@
 static int  gw_udp_recv( void* data );
-static void gw_udp_send( struct can_frame* cf );
+static void gw_udp_send( struct can_frame* cf, struct in_addr ipaddr, u16 port );
 static int  gw_can_recv( void* data );
-static void gw_can_send( struct can_frame* cf );
+static void gw_can_send( struct can_frame* cf, int ifidx );