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No rights are granted, in any manner or form, to use Whistle .\" Communications, Inc. trademarks, including the mark "WHISTLE .\" COMMUNICATIONS" on advertising, endorsements, or otherwise except as .\" such appears in the above copyright notice or in the software. .\" .\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND .\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO .\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, .\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF .\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. .\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY .\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS .\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. .\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES .\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING .\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, .\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR .\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY .\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF .\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY .\" OF SUCH DAMAGE. .\" .\" Author: Archie Cobbs .\" .\" $FreeBSD$ .\" .Dd January 9, 2012 .Dt NG_KSOCKET 4 .Os .Sh NAME .Nm ng_ksocket .Nd kernel socket netgraph node type .Sh SYNOPSIS .In sys/types.h .In netgraph/ng_ksocket.h .Sh DESCRIPTION A .Nm ksocket node is both a netgraph node and a .Bx socket. The .Nm node type allows one to open a socket inside the kernel and have it appear as a Netgraph node. The .Nm node type is the reverse of the socket node type (see .Xr ng_socket 4 ) : whereas the socket node type enables the user-level manipulation (via a socket) of what is normally a kernel-level entity (the associated Netgraph node), the .Nm node type enables the kernel-level manipulation (via a Netgraph node) of what is normally a user-level entity (the associated socket). .Pp A .Nm node allows at most one hook connection. Connecting to the node is equivalent to opening the associated socket. The name given to the hook determines what kind of socket the node will open (see below). When the hook is disconnected and/or the node is shutdown, the associated socket is closed. .Sh HOOKS This node type supports a single hook connection at a time. The name of the hook must be of the form .Em // , where the .Em family , .Em type , and .Em proto are the decimal equivalent of the same arguments to .Xr socket 2 . Alternately, aliases for the commonly used values are accepted as well. For example .Dv inet/dgram/udp is a more readable but equivalent version of .Dv 2/2/17 . .Pp Data received into socket is sent out via hook. Data received on hook is sent out from socket, if the latter is connected (an .Dv NGM_KSOCKET_CONNECT was sent to node before). If socket is not connected, destination .Vt "struct sockaddr" must be supplied in an mbuf tag with cookie .Dv NGM_KSOCKET_COOKIE and type .Dv NG_KSOCKET_TAG_SOCKADDR attached to data. Otherwise .Nm will return .Er ENOTCONN to sender. .Sh CONTROL MESSAGES This node type supports the generic control messages, plus the following: .Bl -tag -width foo .It Dv NGM_KSOCKET_BIND Pq Ic bind This functions exactly like the .Xr bind 2 system call. The .Vt "struct sockaddr" socket address parameter should be supplied as an argument. .It Dv NGM_KSOCKET_LISTEN Pq Ic listen This functions exactly like the .Xr listen 2 system call. The backlog parameter (a single 32 bit .Dv int ) should be supplied as an argument. .It Dv NGM_KSOCKET_CONNECT Pq Ic connect This functions exactly like the .Xr connect 2 system call. The .Vt "struct sockaddr" destination address parameter should be supplied as an argument. .It Dv NGM_KSOCKET_ACCEPT Pq Ic accept Equivalent to the .Xr accept 2 system call on a non-blocking socket. If there is a pending connection on the queue, a new socket and a corresponding cloned node are created. Returned are the cloned node's ID and a peer name (as .Vt "struct sockaddr" ) . If there are no pending connections, this control message returns nothing, and a connected node will receive the above message asynchronously, when a connection is established. .Pp A cloned node supports a single hook with an arbitrary name. If not connected, a node disappears when its parent node is destroyed. Once connected, it becomes an independent node. .It Dv NGM_KSOCKET_GETNAME Pq Ic getname Equivalent to the .Xr getsockname 2 system call. The name is returned as a .Vt "struct sockaddr" in the arguments field of the reply. .It Dv NGM_KSOCKET_GETPEERNAME Pq Ic getpeername Equivalent to the .Xr getpeername 2 system call. The name is returned as a .Vt "struct sockaddr" in the arguments field of the reply. .It Dv NGM_KSOCKET_SETOPT Pq Ic setopt Equivalent to the .Xr setsockopt 2 system call, except that the option name, level, and value are passed in a .Vt "struct ng_ksocket_sockopt" . .It Dv NGM_KSOCKET_GETOPT Pq Ic getopt Equivalent to the .Xr getsockopt 2 system call, except that the option is passed in a .Vt "struct ng_ksocket_sockopt" . When sending this command, the .Dv value field should be empty; upon return, it will contain the retrieved value. .El .Sh ASCII FORM CONTROL MESSAGES For control messages that pass a .Vt "struct sockaddr" in the argument field, the normal .Tn ASCII equivalent of the C structure is an acceptable form. For the .Dv PF_INET and .Dv PF_LOCAL address families, a more convenient form is also used, which is the protocol family name, followed by a slash, followed by the actual address. For .Dv PF_INET , the address is an IP address followed by an optional colon and port number. For .Dv PF_LOCAL , the address is the pathname as a doubly quoted string. .Pp Examples: .Bl -tag -width "PF_LOCAL" .It Dv PF_LOCAL local/"/tmp/foo.socket" .It Dv PF_INET inet/192.168.1.1:1234 .It Other .Dv "\&{ family=16 len=16 data=[0x70 0x00 0x01 0x23] \&}" .El .Pp For control messages that pass a .Vt "struct ng_ksocket_sockopt" , the normal .Tn ASCII form for that structure is used. In the future, more convenient encoding of the more common socket options may be supported. .Pp Setting socket options example: .Bl -tag -width "PF_LOCAL" .It Set FIB 2 for a socket (SOL_SOCKET, SO_SETFIB): .Dv "setopt \&{ level=0xffff name=0x1014 data=[ 2 ] \&}" .El .Sh SHUTDOWN This node shuts down upon receipt of a .Dv NGM_SHUTDOWN control message, or when the hook is disconnected. Shutdown of the node closes the associated socket. .Sh SEE ALSO .Xr socket 2 , .Xr netgraph 4 , .Xr ng_socket 4 , .Xr ngctl 8 , .Xr mbuf_tags 9 , .Xr socket 9 .Sh HISTORY The .Nm node type was implemented in .Fx 4.0 . .Sh AUTHORS .An Archie Cobbs Aq Mt archie@FreeBSD.org