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No rights are granted, in any manner or form, to use Whistle 11.\" Communications, Inc. trademarks, including the mark "WHISTLE 12.\" COMMUNICATIONS" on advertising, endorsements, or otherwise except as 13.\" such appears in the above copyright notice or in the software. 14.\" 15.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 16.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 17.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 18.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 19.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 20.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 21.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 22.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 23.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 24.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 25.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 26.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 27.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 28.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 31.\" OF SUCH DAMAGE. 32.\" 33.\" Author: Archie Cobbs <archie@FreeBSD.org> 34.\" 35.\" $FreeBSD: src/share/man/man4/ng_ether.4,v 1.4.2.12 2002/04/07 04:57:13 dd Exp $ 36.\" $DragonFly: src/share/man/man4/ng_ether.4,v 1.5 2008/05/02 02:05:05 swildner Exp $ 37.\" 38.Dd June 26, 2000 39.Dt NG_ETHER 4 40.Os 41.Sh NAME 42.Nm ng_ether 43.Nd Ethernet netgraph node type 44.Sh SYNOPSIS 45.In netgraph/ether/ng_ether.h 46.Sh DESCRIPTION 47The 48.Nm 49netgraph node type allows Ethernet interfaces to interact with 50the 51.Xr netgraph 4 52networking subsystem. 53Once the 54.Nm 55module is loaded in the kernel, a node is automatically created 56for each Ethernet interface in the system. 57Each node will attempt to name itself with the same name 58as the associated interface. 59All 60.Nm 61nodes are persistent for as long as the interface itself exists. 62.Pp 63Three hooks are supported: 64.Dv lower , 65.Dv upper , 66and 67.Dv orphans . 68The hook name 69.Dv divert 70may be used as an alias for 71.Dv lower , 72and is provided for backward compatibility. 73In reality the two names represent the same hook. 74.Pp 75The 76.Dv lower 77hook is a connection to the raw Ethernet device. 78When connected, all incoming packets are diverted out this hook. 79Writing to this hook results in a raw Ethernet frame being transmitted 80by the device. 81Normal outgoing packets are not affected by 82.Dv lower 83being connected. 84.Pp 85The 86.Dv upper 87hook is a connection to the upper protocol layers. 88When connected, all outgoing packets are diverted out this hook. 89Writing to this hook results in a raw Ethernet frame being received by 90the kernel just as if it had come in over the wire. 91Normal incoming packets are not affected by 92.Dv upper 93being connected. 94.Pp 95The 96.Dv orphans 97hook is equivalent to 98.Dv lower , 99except that only unrecognized packets (that would otherwise be discarded) 100are written to the hook, and normal incoming traffic is unaffected. 101At most one of 102.Dv orphans 103and 104.Dv lower 105may be connected at any time. 106.Pp 107In all cases, frames are raw Ethernet frames with the standard 10814 byte Ethernet header (but no checksum). 109.Pp 110When no hooks are connected, 111.Dv upper 112and 113.Dv lower 114are in effect connected together, 115so that packets flow normally upwards and downwards. 116.Sh HOOKS 117This node type supports the following hooks: 118.Bl -tag -width orphans 119.It Dv lower 120Connection to the lower device link layer. 121.It Dv upper 122Connection to the upper protocol layers. 123.It Dv orphans 124Like 125.Dv lower , 126but only receives unrecognized packets. 127.El 128.Sh CONTROL MESSAGES 129This node type supports the generic control messages, plus the following: 130.Bl -tag -width foo 131.It Dv NGM_ETHER_GET_IFNAME 132Returns the name of the associated interface as a NUL-terminated ASCII string. 133Normally this is the same as the name of the node. 134.It Dv NGM_ETHER_GET_IFINDEX 135Returns the global index of the associated interface as a 32 bit integer. 136.It Dv NGM_ETHER_GET_ENADDR 137Returns the device's unique six byte Ethernet address. 138.It Dv NGM_ETHER_SET_ENADDR 139Sets the device's unique six byte Ethernet address. 140This control message is equivalent to using the 141.Dv SIOCSIFLLADDR 142.Xr ioctl 2 143system call. 144.It Dv NGM_ETHER_SET_PROMISC 145Enable or disable promiscuous mode. 146This message includes a single 32 bit integer flag that enables or 147disables promiscuous mode on the interface. 148.It Dv NGM_ETHER_GET_PROMISC 149Get the current value of the node's promiscuous flag. 150The returned value is always either one or zero. 151Note that this flag reflects the node's own promiscuous setting 152and does not necessarily reflect the promiscuous state of the actual 153interface, which can be affected by other means (e.g., 154.Xr bpf 4 ) . 155.It Dv NGM_ETHER_SET_AUTOSRC 156Sets the automatic source address override flag. 157This message includes a single 32 bit integer flag that causes 158all outgoing packets to have their source Ethernet 159address field overwritten with the device's unique Ethernet address. 160If this flag is set to zero, the source address in outgoing packets 161is not modified. 162The default setting for this flag is enabled. 163.It Dv NGM_ETHER_GET_AUTOSRC 164Get the current value of the node's source address override flag. 165The returned value is always either one or zero. 166.El 167.Sh SHUTDOWN 168This node is persistent for as long as the interface exists. 169Upon receipt of a 170.Dv NGM_SHUTDOWN 171control message, all hooks are disconnected, promiscuous mode is disabled, 172and the source address override flag is reenabled, 173but the node is not removed. 174If the interface itself is detached (e.g., because of PCCARD removal), the 175node disappears as well. 176.Sh EXAMPLES 177This command dumps all unrecognized packets received by the 178.Dv fxp0 179interface to standard output decoded in hex and ASCII: 180.Bd -literal -offset indent 181nghook -a fxp0: orphans 182.Ed 183.Pp 184This command sends the contents of 185.Dv foo.pkt 186out the interface 187.Dv fxp0 : 188.Bd -literal -offset indent 189cat foo.pkt | nghook fxp0: orphans 190.Ed 191.Pp 192These commands insert an 193.Xr ng_tee 4 194node between the lower and upper protocol layers, which can be used for 195tracing packet flow, statistics, etc.: 196.Bd -literal -offset indent 197ngctl mkpeer fxp0: tee lower right 198ngctl connect fxp0: lower upper left 199.Ed 200.Sh SEE ALSO 201.Xr arp 4 , 202.Xr netgraph 4 , 203.Xr netintro 4 , 204.Xr ifconfig 8 , 205.Xr ngctl 8 , 206.Xr nghook 8 207.Sh AUTHORS 208.An Julian Elischer Aq julian@FreeBSD.org 209.An Archie Cobbs Aq archie@FreeBSD.org 210.Sh BUGS 211The automatic KLD module loading mechanism that works for most 212other netgraph node types does not work for the 213.Nm 214node type, 215because 216.Nm 217nodes are not created on demand; instead, they are created when 218Ethernet interfaces are attached or when the KLD is first loaded. 219Therefore, if the KLD is not statically compiled into the kernel, 220it is necessary to load the KLD manually in order to bring the 221.Nm 222nodes into existence. 223