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NAME

ether - Ethernet device

SYNOPSIS 

bind -a #ln /net

/net/ethern/clone

/net/ethern/[0-7]

/net/ethern/[0-7]/data

/net/ethern/[0-7]/ctl

/net/ethern/[0-7]/stats

/net/ethern/[0-7]/type

/net/ethern/[0-7]/ifstats




DESCRIPTION




The Ethernet device
#ln

serves a three-level directory representing a physical Ethernet interface:
AMD LANCE, 3Com 3C509, 3Com 3C905, Intel 82557, and others.
If
n

is not given it is taken to be 0.

The top level directory
has a single directory named
ethern,

where
n

is the interface number, starting from 0,
assigned in some platform-dependent way.
That directory contains a conversation directory for each of 8 Ethernet packet types,
and a
clone

file.

Opening the
clone

file returns a file descriptor open on the
ctl

file of an unused conversation directory.
Reading the
ctl

file returns a text
string representing the number of the
connection.
The connection is controlled by writing textual commands to the associated
ctl

file:



connect type

Set the
type

of Ethernet packets received on the connection; the type is
expressed
as an integer constant
(in hexadecimal if it has a leading
0x,

octal if it has a leading
0,

and otherwise decimal).
For instance, Ethernet packets carrying IP version 4 use type
0x800.

The value
-1

stands for all types.
The value
-2

causes at most the first 64 bytes of all types of packets to be copied
to the conversation.
If several conversations are assigned the same packet type,
a copy of the packet is given to each.

promiscuous


Set the interface to capture all packets regardless of destination address.
An interface normally receives only packets whose 
destination address is that of the interface or is the
broadcast address,
ffffffffffff.

The interface remains promiscuous until the control file is
closed.
The extra packets are received only by conversations of the same type
as the incoming packet (or of type -1).

addmulti address

Add the given MAC multicast
address

to the set of multicast addresses accepted by the interface.
Address

is a twelve digit MAC address in hexadecimal.

remmulti address

Remove
address

from the set of multicast addresses accepted by the interface.



Incoming Ethernet packets are demultiplexed by destination address and
packet type and queued
for reading by the corresponding open connection(s).
Each read of the
data

file returns each packet in turn, including the Ethernet header.
A read will terminate at packet boundaries.
Each write to the
data

file causes a packet to be sent.
The Ethernet address of the interface is inserted into
the packet header as the source address.

Reading the
type

file returns the decimal value of the assigned Ethernet packet type.

Reading the
stats

file returns status information, the value
of counters, the `promiscuous' state,
and the Ethernet MAC address of the
interface.

Reading the
ifstats

file returns statistics and status information specific to a given
hardware interface.

SOURCE




/os/port/devlance.c



/os/port/netif.c



/os/*/devether.c



/os/*/ether*.c


SEE ALSO




ip(3)






ETHER(3
)
Rev:  Tue Mar 31 02:42:38 GMT 2015