1.\" Copyright (c) 1999 Whistle Communications, Inc. 2.\" All rights reserved. 3.\" 4.\" Subject to the following obligations and disclaimer of warranty, use and 5.\" redistribution of this software, in source or object code forms, with or 6.\" without modifications are expressly permitted by Whistle Communications; 7.\" provided, however, that: 8.\" 1. Any and all reproductions of the source or object code must include the 9.\" copyright notice above and the following disclaimer of warranties; and 10.\" 2. 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.\" $FreeBSD$ 36.\" 37.Dd October 28, 2005 38.Dt NG_KSOCKET 4 39.Os 40.Sh NAME 41.Nm ng_ksocket 42.Nd kernel socket netgraph node type 43.Sh SYNOPSIS 44.In sys/types.h 45.In netgraph/ng_ksocket.h 46.Sh DESCRIPTION 47A 48.Nm ksocket 49node is both a netgraph node and a 50.Bx 51socket. 52The 53.Nm 54node type allows one to open a socket inside the kernel and have 55it appear as a Netgraph node. 56The 57.Nm 58node type is the reverse of the socket node type (see 59.Xr ng_socket 4 ) : 60whereas the socket node type enables the user-level manipulation (via 61a socket) of what is normally a kernel-level entity (the associated 62Netgraph node), the 63.Nm 64node type enables the kernel-level manipulation (via a Netgraph node) of 65what is normally a user-level entity (the associated socket). 66.Pp 67A 68.Nm 69node allows at most one hook connection. 70Connecting to the node is 71equivalent to opening the associated socket. 72The name given to the hook 73determines what kind of socket the node will open (see below). 74When the hook is disconnected and/or the node is shutdown, the 75associated socket is closed. 76.Sh HOOKS 77This node type supports a single hook connection at a time. 78The name of the hook must be of the form 79.Em <family>/<type>/<proto> , 80where the 81.Em family , 82.Em type , 83and 84.Em proto 85are the decimal equivalent of the same arguments to 86.Xr socket 2 . 87Alternately, aliases for the commonly used values are accepted as 88well. 89For example 90.Dv inet/dgram/udp 91is a more readable but equivalent version of 92.Dv 2/2/17 . 93.Pp 94Data received into socket is sent out via hook. 95Data received on hook is sent out from socket, if the latter is 96connected (an 97.Dv NGM_KSOCKET_CONNECT 98was sent to node before). 99If socket is not connected, destination 100.Vt "struct sockaddr" 101must be supplied in an mbuf tag with cookie 102.Dv NGM_KSOCKET_COOKIE 103and type 104.Dv NG_KSOCKET_TAG_SOCKADDR 105attached to data. 106Otherwise 107.Nm 108will return 109.Er ENOTCONN 110to sender. 111.Sh CONTROL MESSAGES 112This node type supports the generic control messages, plus the following: 113.Bl -tag -width foo 114.It Dv NGM_KSOCKET_BIND 115This functions exactly like the 116.Xr bind 2 117system call. 118The 119.Vt "struct sockaddr" 120socket address parameter should be supplied as an argument. 121.It Dv NGM_KSOCKET_LISTEN 122This functions exactly like the 123.Xr listen 2 124system call. 125The backlog parameter (a single 32 bit 126.Dv int ) 127should be supplied as an argument. 128.It Dv NGM_KSOCKET_CONNECT 129This functions exactly like the 130.Xr connect 2 131system call. 132The 133.Vt "struct sockaddr" 134destination address parameter should be supplied as an argument. 135.It Dv NGM_KSOCKET_ACCEPT 136Equivalent to the 137.Xr accept 2 138system call on a non-blocking socket. 139If there is a pending connection on the queue, 140a new socket and a corresponding cloned node are created. 141Returned are the cloned node's ID and a peer name (as 142.Vt "struct sockaddr" ) . 143If there are no pending connections, 144this control message returns nothing, 145and a connected node will receive the above message asynchronously, 146when a connection is established. 147.Pp 148A cloned node supports a single hook with an arbitrary name. 149If not connected, a node disappears when its parent node is destroyed. 150Once connected, it becomes an independent node. 151.It Dv NGM_KSOCKET_GETNAME 152Equivalent to the 153.Xr getsockname 2 154system call. 155The name is returned as a 156.Vt "struct sockaddr" 157in the arguments field of the reply. 158.It Dv NGM_KSOCKET_GETPEERNAME 159Equivalent to the 160.Xr getpeername 2 161system call. 162The name is returned as a 163.Vt "struct sockaddr" 164in the arguments field of the reply. 165.It Dv NGM_KSOCKET_SETOPT 166Equivalent to the 167.Xr setsockopt 2 168system call, except that the option name, level, and value are passed in a 169.Vt "struct ng_ksocket_sockopt" . 170.It Dv NGM_KSOCKET_GETOPT 171Equivalent to the 172.Xr getsockopt 2 173system call, except that the option is passed in a 174.Vt "struct ng_ksocket_sockopt" . 175When sending this command, the 176.Dv value 177field should be empty; upon return, it will contain the 178retrieved value. 179.El 180.Sh ASCII FORM CONTROL MESSAGES 181For control messages that pass a 182.Vt "struct sockaddr" 183in the argument field, the normal 184.Tn ASCII 185equivalent of the C structure 186is an acceptable form. 187For the 188.Dv PF_INET 189and 190.Dv PF_LOCAL 191address families, a more convenient form is also used, which is 192the protocol family name, followed by a slash, followed by the actual 193address. 194For 195.Dv PF_INET , 196the address is an IP address followed by an optional colon and port number. 197For 198.Dv PF_LOCAL , 199the address is the pathname as a doubly quoted string. 200.Pp 201Examples: 202.Bl -tag -width XXXXXXXXXX 203.It Dv PF_LOCAL 204local/"/tmp/foo.socket" 205.It Dv PF_INET 206inet/192.168.1.1:1234 207.It Other 208.Dv "\&{ family=16 len=16 data=[0x70 0x00 0x01 0x23] \&}" 209.El 210.Pp 211For control messages that pass a 212.Vt "struct ng_ksocket_sockopt" , 213the normal 214.Tn ASCII 215form for that structure is used. 216In the future, more 217convenient encoding of the more common socket options may be supported. 218.Sh SHUTDOWN 219This node shuts down upon receipt of a 220.Dv NGM_SHUTDOWN 221control message, or when the hook is disconnected. 222Shutdown of the node closes the associated socket. 223.Sh SEE ALSO 224.Xr socket 2 , 225.Xr netgraph 4 , 226.Xr ng_socket 4 , 227.Xr ngctl 8 , 228.Xr mbuf_tags 9 , 229.Xr socket 9 230.Sh HISTORY 231The 232.Nm 233node type was implemented in 234.Fx 4.0 . 235.Sh AUTHORS 236.An Archie Cobbs Aq archie@FreeBSD.org 237