ng_eiface (4)
Leading comments
Copyright (c) 2004 Gleb Smirnoff 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 othe...
NAME
ng_eiface - generic Ethernet interface netgraph node typeSYNOPSIS
In netgraph/ng_eiface.hDESCRIPTION
The Vt eiface netgraph node implements the generic Ethernet interface. When Vt eiface node is created, a new interface appears which is accessible via ifconfig(8). These interfaces are named ``ngeth0 '' ``ngeth1 '' etc. When a node is shut down, the corresponding interface is removed, and the interface name becomes available for reuse by future Vt eiface nodes. New nodes always take the first unused interface.HOOKS
An Vt eiface node has a single hook named ether which should be connected to the Ethernet downstream, for example, to the ng_vlan4 node. Packets transmitted via the interface flow out this hook. Similarly, packets received on the hook go to the protocol stack as packets received by any real Ethernet interface.CONTROL MESSAGES
This node type supports the generic control messages, plus the following:- NGM_EIFACE_SET (set )
- Set link-level address of the interface. Requires Vt struct ether_addr as an argument. This message also has an ASCII version, called ``set '' which requires as an argument an ASCII string consisting of 6 colon-separated hex digits.
- NGM_EIFACE_GET_IFNAME (getifname )
- Return the name of the associated interface as a NUL -terminated ASCII string.
- NGM_EIFACE_GET_IFADDRS
- Return the list of link-level addresses associated with the node.
SHUTDOWN
This node shuts down upon receipt of a NGM_SHUTDOWN control message. The associated interface is removed and its name becomes available for reuse by future Vt eiface nodes.Unlike most other node types, an Vt eiface node does not go away when all hooks have been disconnected; rather, and explicit NGM_SHUTDOWN control message is required.