1 .\" Copyright (c) 1996-1999 Whistle Communications, Inc.
2 .\" All rights reserved.
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.
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
33 .\" Author: Archie Cobbs <archie@whistle.com>
35 .\" $FreeBSD: src/lib/libnetgraph/netgraph.3,v 1.4.2.10 2002/12/29 16:35:36 schweikh Exp $
36 .\" $Whistle: netgraph.3,v 1.7 1999/01/25 07:14:06 archie Exp $
50 .Nd netgraph user library
56 .Fn NgMkSockNode "const char *name" "int *csp" "int *dsp"
58 .Fn NgNameNode "int cs" "const char *path" "const char *fmt" "..."
60 .Fn NgSendMsg "int cs" "const char *path" "int cookie" "int cmd" "const void *arg" "size_t arglen"
62 .Fn NgSendAsciiMsg "int cs" "const char *path" "const char *fmt" "..."
64 .Fn NgSendMsgReply "int cs" "const char *path" "struct ng_mesg *msg" "const void *arg" "size_t arglen"
66 .Fn NgRecvMsg "int cs" "struct ng_mesg *rep" "size_t replen" "char *path"
68 .Fn NgRecvAsciiMsg "int cs" "struct ng_mesg *rep" "size_t replen" "char *path"
70 .Fn NgSendData "int ds" "const char *hook" "const u_char *buf" "size_t len"
72 .Fn NgRecvData "int ds" "u_char *buf" "size_t len" "char *hook"
74 .Fn NgSetDebug "int level"
76 .Fn NgSetErrLog "void (*log)(const char *fmt, ...)" "void (*logx)(const char *fmt, ...)"
78 These functions facilitate user-mode program participation in the kernel
80 graph-based networking system, by utilizing the netgraph
86 should be called first, to create a new
88 type netgraph node with associated control and data sockets. If
90 is non-NULL, the node will have that global name assigned to it.
94 will be set to the newly opened control and data sockets
95 associated with the node; either
99 may be NULL if only one socket is desired.
101 loads the socket node type KLD if it's not already loaded.
104 assigns a global name to the node addressed by
108 sends a binary control message from the socket node associated
111 to the node addressed by
115 indicates how to interpret
117 which indicates a specific command.
118 Extra argument data (if any) is specified by
125 and argument data are defined by the header file corresponding
126 to the type of the node being addressed.
127 The unique, non-negative token value chosen for use in the message
128 header is returned. This value is typically used to associate replies.
132 to send reply to a previously received control message.
133 The original message header should be pointed to by
137 performs the same function as
141 encoding of control messages.
143 formats its input a la
145 and then sends the resulting
147 string to the node in a
149 control message. The node returns a binary version of the
150 message, which is then sent back to the node just as with
154 the message token value is returned.
157 conversion may not be supported by all node types.
160 reads the next control message received by the node associated with
163 The message and any extra argument data must fit in
168 is non-NULL, it must point to a buffer of at least
170 bytes, which will be filled in (and NUL terminated) with the path to
171 the node from which the message was received.
173 The length of the control message is returned.
174 A return value of zero indicates that the socket was closed.
179 except that after the message is received, any binary arguments
184 request back to the originating node. The result is the same as
186 with the exception that the reply arguments field will contain
189 version of the arguments (and the reply
190 header argument length field will be adjusted).
193 writes a data packet out on the specified hook of the node corresponding
196 The node must already be connected to some other node via that hook.
199 reads the next data packet (of up to
201 bytes) received by the node corresponding to data socket
205 which must be large enough to hold the entire packet. If
207 is non-NULL, it must point to a buffer of at least
209 bytes, which will be filled in (and NUL terminated) with the name of
210 the hook on which the data was received.
212 The length of the packet is returned.
213 A return value of zero indicates that the socket was closed.
218 are used for debugging.
220 sets the debug level (if non-negative), and returns the old setting.
221 Higher debug levels result in more verbosity. The default is zero.
222 All debug and error messages are logged via the functions
223 specified in the most recent call to
225 The default logging functions are
230 At debug level 3, the library attempts to display control message arguments
233 format; however, this results in additional messages being
234 sent which may interfere with debugging. At even higher levels,
235 even these additional messages will be displayed, etc.
239 can be used on the data and the control sockets to detect the presence of
240 incoming data and control messages, respectively.
241 Data and control packets are always written and read atomically, i.e.,
244 User mode programs must be linked with the
246 flag to link in this library.
248 To enable Netgraph in your kernel, either your kernel must be
251 in the kernel configuration
256 KLD modules must have been loaded via
260 returns the previous debug setting.
263 All other functions return \-1 if there was an error and set
266 A return value of zero from
270 indicates that the netgraph socket has been closed.
276 the following additional errors are possible:
279 The node type does not know how to encode or decode the control message.
281 The encoded or decoded arguments were too long for the supplied buffer.
283 An unknown structure field was seen in an
287 The same structure field was specified twice in an
292 control message parse error or illegal value.
294 ASCII control message array or fixed width string buffer overflow.
306 system was designed and first implemented at Whistle Communications, Inc. in
309 customized for the Whistle InterJet.
311 .An Archie Cobbs Aq archie@whistle.com