identd.tproj/identd.8

   1 .\" @(#)identd.8 1.9 92/02/11 Lysator
   2 .\" Copyright (c) 1992 Peter Eriksson, Lysator, Linkoping University.
   3 .\" This software has been released into the public domain.
   4 .\"
   5 .\"     $Id: identd.8,v 1.2 2002/03/29 01:34:27 bbraun Exp $
   6 .\"
   7 .TH IDENTD 8 "27 May 1992"
   8 .SH NAME
   9 identd \- TCP/IP IDENT protocol server
  10 .SH SYNOPSIS
  11 .B identd
  12 .RB [ \-i | \-w | \-b ]
  13 .RB [ \-t<seconds> ]
  14 .RB [ \-u<uid> ]
  15 .RB [ \-g<gid> ]
  16 .RB [ \-p<port> ]
  17 .RB [ \-a<address> ]
  18 .RB [ \-c<charset> ]
  19 .RB [ \-n ]
  20 .RB [ \-o ]
  21 .RB [ \-e ]
  22 .RB [ \-l ]
  23 .RB [ \-V ]
  24 .RB [ \-v ]
  25 .RB [ \-m ]
  26 .RB [ \-N ]
  27 .RB [ \-d ]
  28 .RB [ kernelfile [ kmemfile ] ]
  29 .SH DESCRIPTION
  30 .IX "identd daemon" "" \fLidentd\fP daemon"
  31 .B identd
  32 is a server which implements the
  33 .SM TCP/IP
  34 proposed standard
  35 .SM IDENT
  36 user identification protocol as specified in the
  37 .SM RFC\s0 1413
  38 document.
  39 .PP
  40 .B identd
  41 operates by looking up specific
  42 .SM TCP/IP
  43 connections and returning the user name of the
  44 process owning the connection.
  45 .SH ARGUMENTS
  46 The
  47 .B -i
  48 flag, which is the default mode, should be used when starting the
  49 daemon from
  50 .B inetd
  51 with the "nowait" option in the
  52 .B /etc/inetd.conf
  53 file. Use of this mode will make
  54 .B inetd
  55 start one
  56 .B identd
  57 daemon for each connection request.
  58 .PP
  59 The
  60 .B -w
  61 flag should be used when starting the daemon from
  62 .B inetd
  63 with the "wait" option in the
  64 .B /etc/inetd.conf
  65 file . This is the preferred mode of
  66 operation since that will start a copy of
  67 .B identd
  68 at the first connection request and then
  69 .B identd
  70 will handle subsequent requests
  71 without having to do the nlist lookup in the kernel file for
  72 every request as in the
  73 .B -i
  74 mode above. The
  75 .B identd
  76 daemon will run either forever, until a bug
  77 makes it crash or a timeout, as specified by the
  78 .B -t
  79 flag, occurs.
  80 .PP
  81 The
  82 .B -b
  83 flag can be used to make the daemon run in standalone mode without
  84 the assistance from
  85 .B inetd.
  86 This mode is the least preferred mode since
  87 a bug or any other fatal condition in the server will make it terminate
  88 and it will then have to be restarted manually. Other than that is has the
  89 same advantage as the
  90 .B -w
  91 mode in that it parses the nlist only once.
  92 .PP
  93 The
  94 .B -t<seconds>
  95 option is used to specify the timeout limit. This is the number
  96 of seconds a server started with the
  97 .B -w
  98 flag will wait for new connections before terminating. The server is
  99 automatically restarted by
 100 .B inetd
 101 whenever a new connection is requested
 102 if it has terminated. A suitable value for this is 120 (2 minutes), if
 103 used. It defaults to no timeout (ie, will wait forever, or until a
 104 fatal condition occurs in the server).
 105 .PP
 106 The
 107 .B -u<uid>
 108 option is used to specify a user id number which the
 109 .B ident
 110 server should
 111 switch to after binding itself to the
 112 .SM TCP/IP
 113 port if using the
 114 .B -b
 115 mode of operation.
 116 .PP
 117 The
 118 .B -g<gid>
 119 option is used to specify a group id number which the
 120 .B ident
 121 server should
 122 switch to after binding itself to the
 123 .SM TCP/IP
 124 port if using the
 125 .B -b
 126 mode of operation.
 127 .PP
 128 The
 129 .B -p<port>
 130 option is used to specify an alternative port number to bind to if using
 131 the
 132 .B -b
 133 mode of operation. It can be specified by name or by number. Defaults to the
 134 .SM IDENT
 135 port (113).
 136 .PP
 137 The
 138 .B -a<address>
 139 option is used to specify the local address to bind the socket to if using
 140 the
 141 .B -b
 142 mode of operation. Can only be specified by IP address and not by domain
 143 name. Defaults to the
 144 .SM INADDR_ANY
 145 address which normally means all local addresses.
 146 .PP
 147 The
 148 .B -V
 149 flag makes
 150 .B identd
 151 display the version number and the exit.
 152 .PP
 153 The
 154 .B -l
 155 flag tells
 156 .B identd
 157 to use the System logging daemon
 158 .B syslogd
 159 for logging purposes.
 160 .PP
 161 The
 162 .B -v
 163 flag causes
 164 .B identd
 165 to log every request made, if the use of
 166 .B syslogd
 167 is enabled.
 168 .PP
 169 The
 170 .B -o
 171 flag tells
 172 .B identd
 173 to not reveal the operating system type it is run on and to instead
 174 always return "OTHER".
 175 .PP
 176 The
 177 .B -e
 178 flag tells
 179 .B identd
 180 to always return "UNKNOWN-ERROR" instead of the "NO-USER" or
 181 "INVALID-PORT" errors.
 182 .PP
 183 The
 184 .B -c<charset>
 185 flags tells
 186 .B identd
 187 to add the optional (according to the IDENT protocol) character set
 188 designator to the reply generated. <charset> should be a valid character
 189 set as described in the MIME RFC in upper case characters.
 190 .PP
 191 The
 192 .B -n
 193 flags tells
 194 .B identd
 195 to always return user numbers instead of user names if you wish to
 196 keep the user names a secret.
 197 .PP
 198 The
 199 .B -N
 200 flag makes
 201 .B identd
 202 check for a file ".noident" in each homedirectory for a user which the
 203 daemon is about to return the user name for. It that file exists then the
 204 daemon will give the error
 205 .B HIDDEN-USER
 206 instead of the normal USERID response.
 207 .PP
 208 .B -m
 209 flag makes
 210 .B identd
 211 use a mode of operation that will allow multiple requests to be
 212 processed per session. Each request is specified one per line and
 213 the responses will be returned one per line. The connection will not
 214 be closed until the connecting part closes it's end of the line.
 215 PLEASE NOTE THAT THIS MODE VIOLATES THE PROTOCOL SPECIFICATION AS
 216 IT CURRENTLY STANDS.
 217 .PP
 218 The
 219 .B -d
 220 flag enables some debugging code that normally should NOT
 221 be enabled since that breaks the protocol and may reveal information
 222 that should not be available to outsiders.
 223 .PP
 224 .B kernelfile
 225 defaults to the normally running kernel file.
 226 .PP
 227 .B kmemfile
 228 defaults to the memory space of the normally running kernel.
 229 .SH SEE ALSO
 230 .BR inetd.conf (5)
 231 .SH BUGS
 232 The handling of fatal errors could be better.
 233 .PP
 234 If the
 235 .B -N
 236 flag is specified and a user's ".noident" file is not accessible,
 237 then ident information regarding that user will be returned
 238 if requested.