xref: /dragonfly/libexec/bootpd/bootptab.5 (revision a4da4a90)
1.\" Copyright (c) 1988, 1989, 1991 Carnegie Mellon University
2.\"
3.\" $FreeBSD: src/libexec/bootpd/bootptab.5,v 1.4.2.4 2001/08/16 10:44:13 ru Exp $
4.\" $DragonFly: src/libexec/bootpd/bootptab.5,v 1.4 2008/05/02 02:05:04 swildner Exp $
5.\"
6.Dd October 31, 1991
7.Dt BOOTPTAB 5
8.Os
9.Sh NAME
10.Nm bootptab
11.Nd Internet Bootstrap Protocol server database
12.Sh DESCRIPTION
13The
14.Nm
15file is the configuration database file for
16.Xr bootpd 8 ,
17the Internet Bootstrap Protocol server.
18Its format is similar to that of
19.Xr termcap 5
20in which two-character case-sensitive tag symbols are used to
21represent host parameters.  These parameter declarations are separated by
22colons (:), with a general format of:
23.Pp
24.Dl "hostname:tg=value. . . :tg=value. . . :tg=value. . . ."
25.Pp
26where
27.Em hostname
28is the actual name of a bootp client (or a "dummy entry"), and
29.Em tg
30is a two-character tag symbol.  Dummy entries have an invalid hostname
31(one with a "." as the first character) and are used to provide
32default values used by other entries via the
33.Em tc=.dummy-entry
34mechanism.  Most tags must be followed by an equals-sign
35and a value as above.  Some may also appear in a boolean form with no
36value (i.e.\&
37.Em :tg: ) .
38The currently recognized tags are:
39.Pp
40.Bl -tag -width xxx -compact
41.It bf
42Bootfile
43.It bs
44Bootfile size in 512-octet blocks
45.It cs
46Cookie server address list
47.It df
48Merit dump file
49.It dn
50Domain name
51.It ds
52Domain name server address list
53.It ef
54Extension file
55.It gw
56Gateway address list
57.It ha
58Host hardware address
59.It hd
60Bootfile home directory
61.It hn
62Send client's hostname to client
63.It ht
64Host hardware type (see Assigned Numbers RFC)
65.It im
66Impress server address list
67.It ip
68Host IP address
69.It lg
70Log server address list
71.It lp
72LPR server address list
73.It ns
74IEN-116 name server address list
75.It nt
76NTP (time) Server (RFC 1129)
77.It ra
78Reply address override
79.It rl
80Resource location protocol server address list
81.It rp
82Root path to mount as root
83.It sa
84TFTP server address client should use
85.It sm
86Host subnet mask
87.It sw
88Swap server address
89.It tc
90Table continuation (points to similar "template" host entry)
91.It td
92TFTP root directory used by "secure" TFTP servers
93.It to
94Time offset in seconds from UTC
95.It ts
96Time server address list
97.It vm
98Vendor magic cookie selector
99.It yd
100YP (NIS) domain name
101.It ys
102YP (NIS) server address
103.El
104.Pp
105There is also a generic tag,
106.Pf T Em n ,
107where
108.Em n
109is an RFC 1084 vendor field tag number.  Thus it is possible to immediately
110take advantage of future extensions to RFC 1084 without being forced to modify
111.Nm bootpd
112first.  Generic data may be represented as either a stream of hexadecimal
113numbers or as a quoted string of
114.Tn ASCII
115characters.  The length of the generic
116data is automatically determined and inserted into the proper field(s) of the
117RFC 1084 style bootp reply.
118.Pp
119The following tags take a whitespace-separated list of IP addresses:
120.Em cs ,
121.Em ds ,
122.Em gw ,
123.Em im ,
124.Em lg ,
125.Em lp ,
126.Em ns ,
127.Em nt ,
128.Em ra ,
129.Em rl ,
130and
131.Em ts .
132The
133.Em ip ,
134.Em sa ,
135.Em sw ,
136.Em sm ,
137and
138.Em ys
139tags each take a single IP address.
140All IP addresses are specified in standard Internet "dot" notation
141and may use decimal, octal, or hexadecimal numbers
142(octal numbers begin with 0, hexadecimal numbers begin with '0x' or '0X').
143Any IP addresses may alternatively be specified as a hostname, causing
144.Nm bootpd
145to lookup the IP address for that host name using
146.Xr gethostbyname 3 .
147If the
148.Em ip
149tag is not specified,
150.Nm bootpd
151will determine the IP address using the entry name as the host name.
152(Dummy entries use an invalid host name to avoid automatic IP lookup.)
153.Pp
154The
155.Em ht
156tag specifies the hardware type code as either an unsigned decimal, octal, or
157hexadecimal integer or one of the following symbolic names:
158.Em ethernet
159or
160.Em ether
161for 10Mb Ethernet,
162.Em ethernet3
163or
164.Em ether3
165for 3Mb experimental Ethernet,
166.Em ieee802 ,
167.Em tr ,
168or
169.Em token-ring
170for IEEE 802 networks,
171.Em pronet
172for Proteon ProNET Token Ring, or
173.Em chaos ,
174.Em arcnet ,
175or
176.Em ax.25
177for Chaos, ARCNET, and AX.25 Amateur Radio networks, respectively.
178The
179.Em ha
180tag takes a hardware address which may be specified as a host name
181or in numeric form.  Note that the numeric form
182.Em must
183be specified in hexadecimal; optional periods and/or a leading '0x' may be
184included for readability.  The
185.Em ha
186tag must be preceded by the
187.Em ht
188tag (either explicitly or implicitly; see
189.Em tc
190below).
191If the hardware address is not specified and the type is specified
192as either "ethernet" or "ieee802", then
193.Nm bootpd
194will try to determine the hardware address using
195.Xr ether_hostton 3 .
196.Pp
197The hostname, home directory, and bootfile are
198.Tn ASCII
199strings which may be
200optionally surrounded by double quotes (").  The client's request and the
201values of the
202.Em hd
203and
204.Em bf
205symbols determine how the server fills in the bootfile field of the bootp
206reply packet.
207.Pp
208If the client provides a file name it is left as is.
209Otherwise, if the
210.Em bf
211option is specified its value is copied into the reply packet.
212If the
213.Em hd
214option is specified as well, its value is prepended to the
215boot file copied into the reply packet.
216The existence of the boot file is checked only if the
217.Em bs Ns =auto
218option is used (to determine the boot file size).
219A reply may be sent whether or not the boot file exists.
220.Pp
221Some newer versions of
222.Xr tftpd 8
223provide a security feature to change their root directory using
224the
225.Xr chroot 2
226system call.
227The
228.Em td
229tag may be used to inform
230.Nm bootpd
231of this special root directory used by
232.Nm tftpd .
233(One may alternatively use the
234.Nm bootpd
235.Fl c Ar chdir
236option.)
237The
238.Em hd
239tag is actually relative to the root directory specified by the
240.Em td
241tag.
242For example, if the real absolute path to your BOOTP client bootfile is
243.Pa /tftpboot/bootfiles/bootimage ,
244and
245.Nm tftpd
246uses
247.Pa /tftpboot
248as its "secure" directory, then specify the following in
249.Pa bootptab :
250.Pp
251.Dl :td=/tftpboot:hd=/bootfiles:bf=bootimage:
252.Pp
253If your bootfiles are located directly in
254.Pa /tftpboot ,
255use:
256.Pp
257.Dl :td=/tftpboot:hd=/:bf=bootimage:
258.Pp
259The
260.Em sa
261tag may be used to specify the IP address of the particular TFTP server
262you wish the client to use.  In the absence of this tag,
263.Nm bootpd
264will tell the client to perform TFTP to the same machine
265.Nm bootpd
266is running on.
267.Pp
268The time offset
269.Em to
270may be either a signed decimal integer specifying the client's
271time zone offset in seconds from UTC, or the keyword
272.Em auto
273which uses the server's time zone offset.  Specifying the
274.Em to
275symbol as a boolean has the same effect as specifying
276.Em auto
277as its value.
278.Pp
279The bootfile size
280.Em bs
281may be either a decimal, octal, or hexadecimal integer specifying the size of
282the bootfile in 512-octet blocks, or the keyword
283.Em auto
284which causes the server to automatically calculate the bootfile size at each
285request.  As with the time offset, specifying the
286.Em bs
287symbol as a boolean has the same effect as specifying
288.Em auto
289as its value.
290.Pp
291The vendor magic cookie selector (the
292.Em vm
293tag) may take one of the following keywords:
294.Em auto
295(indicating that vendor information is determined by the client's request),
296.Em rfc1048
297or
298.Em rfc1084
299(which always forces an RFC 1084 style reply), or
300.Em cmu
301(which always forces a CMU style reply).
302.Pp
303The
304.Em hn
305tag is strictly a boolean tag; it does not take the usual equals-sign and
306value.  Its presence indicates that the hostname should be sent to RFC 1084
307clients.
308.Nm Bootpd
309attempts to send the entire hostname as it is specified in the configuration
310file; if this will not fit into the reply packet, the name is shortened to
311just the host field (up to the first period, if present) and then tried.
312In no case is an arbitrarily-truncated hostname sent (if nothing reasonable
313will fit, nothing is sent).
314.Pp
315Often, many host entries share common values for certain tags (such as name
316servers, etc.).  Rather than repeatedly specifying these tags, a full
317specification can be listed for one host entry and shared by others via the
318.Em tc
319(table continuation) mechanism.
320Often, the template entry is a dummy host which doesn't actually exist and
321never sends bootp requests.  This feature is similar to the
322.Em tc
323feature of
324.Xr termcap 5
325for similar terminals.  Note that
326.Nm bootpd
327allows the
328.Em tc
329tag symbol to appear anywhere in the host entry, unlike
330.Pa termcap
331which requires it to be the last tag.  Information explicitly specified for a
332host always overrides information implied by a
333.Em tc
334tag symbol, regardless of its location within the entry.  The
335value of the
336.Em tc
337tag may be the hostname or IP address of any host entry
338previously listed in the configuration file.
339.Pp
340Sometimes it is necessary to delete a specific tag after it has been inferred
341via
342.Em tc .
343This can be done using the construction
344.Em tag Ns @
345which removes the effect of
346.Em tag
347as in
348.Xr termcap 5 .
349For example, to completely undo an IEN-116 name server specification, use
350.Em :ns@:
351at an appropriate place in the configuration entry.  After removal
352with
353.Em @ ,
354a tag is eligible to be set again through the
355.Em tc
356mechanism.
357.Pp
358Blank lines and lines beginning with "#" are ignored in the configuration
359file.  Host entries are separated from one another by newlines; a single host
360entry may be extended over multiple lines if the lines end with a backslash
361(\\).  It is also acceptable for lines to be longer than 80 characters.  Tags
362may appear in any order, with the following exceptions:  the hostname must be
363the very first field in an entry, and the hardware type must precede the
364hardware address.
365.Pp
366An example
367.Pa /etc/bootptab
368file follows:
369.Bd -literal -offset indent
370# Sample bootptab file (domain=andrew.cmu.edu)
371
372\&.default:\\
373	:hd=/usr/boot:bf=null:\\
374	:ds=netserver, lancaster:\\
375	:ns=pcs2, pcs1:\\
376	:ts=pcs2, pcs1:\\
377	:sm=255.255.255.0:\\
378	:gw=gw.cs.cmu.edu:\\
379	:hn:to=-18000:
380
381carnegie:ht=6:ha=7FF8100000AF:tc=.default:
382baldwin:ht=1:ha=0800200159C3:tc=.default:
383wylie:ht=1:ha=00DD00CADF00:tc=.default:
384arnold:ht=1:ha=0800200102AD:tc=.default:
385bairdford:ht=1:ha=08002B02A2F9:tc=.default:
386bakerstown:ht=1:ha=08002B0287C8:tc=.default:
387
388# Special domain name server and option tags for next host
389butlerjct:ha=08002001560D:ds=128.2.13.42:\\
390	:T37=0x12345927AD3BCF:\\
391	:T99="Special ASCII string":\\
392	:tc=.default:
393
394gastonville:ht=6:ha=7FFF81000A47:tc=.default:
395hahntown:ht=6:ha=7FFF81000434:tc=.default:
396hickman:ht=6:ha=7FFF810001BA:tc=.default:
397lowber:ht=1:ha=00DD00CAF000:tc=.default:
398mtoliver:ht=1:ha=00DD00FE1600:tc=.default:
399.Ed
400.Sh FILES
401.Bl -tag -width /etc/bootptab -compact
402.It /etc/bootptab
403.El
404.Sh "SEE ALSO"
405.Xr bootpd 8 ,
406.Xr tftpd 8
407.Pp
408DARPA Internet Request For Comments RFC 951, RFC 1048, RFC 1084,
409Assigned Numbers
410