1.\" Copyright (c) 1996 David Nugent <davidn@blaze.net.au> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, is permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice immediately at the beginning of the file, without modification, 9.\" this list of conditions, and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 3. This work was done expressly for inclusion into FreeBSD. Other use 14.\" is permitted provided this notation is included. 15.\" 4. Absolutely no warranty of function or purpose is made by the author 16.\" David Nugent. 17.\" 5. Modifications may be freely made to this file providing the above 18.\" conditions are met. 19.\" 20.\" $FreeBSD$ 21.\" 22.Dd August 20, 2008 23.Dt LOGIN.CONF 5 24.Os 25.Sh NAME 26.Nm login.conf 27.Nd login class capability database 28.Sh SYNOPSIS 29.Pa /etc/login.conf , 30.Pa ~/.login_conf 31.Sh DESCRIPTION 32.Nm 33contains various attributes and capabilities of login classes. 34A login class (an optional annotation against each record in the user 35account database, 36.Pa /etc/master.passwd ) 37determines session accounting, resource limits and user environment settings. 38It is used by various programs in the system to set up a user's login 39environment and to enforce policy, accounting and administrative restrictions. 40It also provides the means by which users are able to be 41authenticated to the system and the types of authentication available. 42Attributes in addition to the ones described here are available with 43third-party packages. 44.Pp 45A special record "default" in the system user class capability database 46.Pa /etc/login.conf 47is used automatically for any 48non-root user without a valid login class in 49.Pa /etc/master.passwd . 50A user with a uid of 0 without a valid login class will use the record 51"root" if it exists, or "default" if not. 52.Pp 53In 54.Fx , 55users may individually create a file called 56.Pa .login_conf 57in their home directory using the same format, consisting of a single 58entry with a record id of "me". 59If present, this file is used by 60.Xr login 1 61to set user-defined environment settings which override those specified 62in the system login capabilities database. 63Only a subset of login capabilities may be overridden, typically those 64which do not involve authentication, resource limits and accounting. 65.Pp 66Records in a class capabilities database consist of a number of 67colon-separated fields. 68The first entry for each record gives one or more names that a record is 69to be known by, each separated by a '|' character. 70The first name is the most common abbreviation. 71The last name given should be a long name that is more descriptive 72of the capability entry, and all others are synonyms. 73All names but the last should be in lower case and contain no blanks; 74the last name may contain upper case characters and blanks for 75readability. 76.Pp 77Note that since a colon 78.Pq Ql :\& 79is used to separate capability entries, a 80.Ql \ec 81escape sequence must be used to embed a literal colon in the 82value or name of a capability. 83.Pp 84The default 85.Pa /etc/login.conf 86shipped with 87.Fx 88is an out of the box configuration. 89Whenever changes to this, or 90the user's 91.Pa ~/.login_conf , 92file are made, the modifications will not be picked up until 93.Xr cap_mkdb 1 94is used to compile the file into a database. 95This database file will have a 96.Pa .db 97extension and is accessed through 98.Xr cgetent 3 . 99See 100.Xr getcap 3 101for a more in-depth description of the format of a capability database. 102.Sh CAPABILITIES 103Fields within each record in the database follow the 104.Xr getcap 3 105conventions for boolean, type string 106.Ql \&= 107and type numeric 108.Ql \&# , 109although type numeric is deprecated in favour of the string format and 110either form is accepted for a numeric datum. 111Values fall into the following categories: 112.Bl -tag -width "program" 113.It bool 114If the name is present, then the boolean value is true; otherwise, it is 115false 116.It file 117Path name to a data file 118.It program 119Path name to an executable file 120.It list 121A list of values (or pairs of values) separated by commas or spaces 122.It path 123A space or comma separated list of path names, following the usual csh 124conventions (leading tilde with and without username being expanded to 125home directories etc.) 126.It number 127A numeric value, either decimal (default), hexadecimal (with leading 0x), 128or octal (with a leading 0). 129With a numeric type, only one numeric value is allowed. 130Numeric types may also be specified in string format (i.e., the capability 131tag being delimited from the value by '=' instead of '#'). 132Whichever method is used, then all records in the database must use the 133same method to allow values to be correctly overridden in interpolated 134records. 135.It size 136A number which expresses a size. 137The default interpretation of a value is the number of bytes, but a 138suffix may specify alternate units: 139.Bl -tag -offset indent -compact -width xxxx 140.It b 141explicitly selects 512-byte blocks 142.It k 143selects kilobytes (1024 bytes) 144.It m 145specifies a multiplier of 1 megabyte (1048576 bytes), 146.It g 147specifies units of gigabytes, and 148.It t 149represents terabytes. 150.El 151A size value is a numeric quantity and case of the suffix is not significant. 152Concatenated values are added together. 153.It time 154A period of time, by default in seconds. 155A prefix may specify a different unit: 156.Bl -tag -offset indent -compact -width xxxx 157.It y 158indicates the number of 365 day years, 159.It w 160indicates the number of weeks, 161.It d 162the number of days, 163.It h 164the number of hours, 165.It m 166the number of minutes, and 167.It s 168the number of seconds. 169.El 170Concatenated values are added together. 171For example, 2 hours and 40 minutes may be written either as 1729600s, 160m or 2h40m. 173.El 174.Pp 175The usual convention to interpolate capability entries using the special 176.Em tc=value 177notation may be used. 178.Sh RESOURCE LIMITS 179.Bl -column pseudoterminals indent indent 180.It Sy "Name Type Notes Description 181.It "coredumpsize size Maximum coredump size limit. 182.It "cputime time CPU usage limit. 183.It "datasize size Maximum data size limit. 184.It "filesize size Maximum file size limit. 185.It "maxproc number Maximum number of processes. 186.It "memorylocked size Maximum locked in core memory size limit. 187.It "memoryuse size Maximum of core memory use size limit. 188.It "openfiles number Maximum number of open files per process. 189.It "sbsize size Maximum permitted socketbuffer size. 190.It "vmemoryuse size Maximum permitted total VM usage per process. 191.It "stacksize size Maximum stack size limit. 192.It "pseudoterminals number Maximum number of pseudo-terminals. 193.El 194.Pp 195These resource limit entries actually specify both the maximum 196and current limits (see 197.Xr getrlimit 2 ) . 198The current (soft) limit is the one normally used, although the user is 199permitted to increase the current limit to the maximum (hard) limit. 200The maximum and current limits may be specified individually by appending a 201-max or -cur to the capability name. 202.Sh ENVIRONMENT 203.Bl -column ignorenologin indent xbinxxusrxbin 204.It Sy "Name Type Notes Description 205.It "charset string Set $MM_CHARSET environment variable to the specified 206value. 207.It "cpumask string List of cpus to bind the user to. 208The syntax is the same as for the 209.Fl l 210argument of 211.Xr cpuset 1 or the word 212.Ql default . 213If set to 214.Ql default 215no action is taken. 216.It "hushlogin bool false Same as having a ~/.hushlogin file. 217.It "ignorenologin bool false Login not prevented by nologin. 218.It "ftp-chroot bool false Limit FTP access with 219.Xr chroot 2 220to the 221.Ev HOME 222directory of the user. 223See 224.Xr ftpd 8 225for details. 226.It "label string Default MAC policy; see 227.Xr maclabel 7 . 228.It "lang string Set $LANG environment variable to the specified value. 229.It "manpath path Default search path for manpages. 230.It "nocheckmail bool false Display mail status at login. 231.It "nologin file If the file exists it will be displayed and 232the login session will be terminated. 233.It "path path /bin /usr/bin Default search path. 234.It "priority number Initial priority (nice) level. 235.It "requirehome bool false Require a valid home directory to login. 236.It "setenv list A comma-separated list of environment variables and 237values to which they are to be set. 238.It "shell prog Session shell to execute rather than the 239shell specified in the passwd file. 240The SHELL environment variable will 241contain the shell specified in the password file. 242.It "term string Default terminal type if not able to determine 243from other means. 244.It "timezone string Default value of $TZ environment variable. 245.It "umask number 022 Initial umask. Should always have a leading 0 to 246ensure octal interpretation. 247.It "welcome file /etc/motd File containing welcome message. 248.El 249.Sh AUTHENTICATION 250.Bl -column passwd_prompt indent indent 251.It Sy "Name Type Notes Description 252.\" .It "approve program Program to approve login. 253.It "copyright file File containing additional copyright information 254.It "host.allow list List of remote host wildcards from which users in 255the class may access. 256.It "host.deny list List of remote host wildcards from which users 257in the class may not access. 258.It "login_prompt string The login prompt given by 259.Xr login 1 260.It "login-backoff number 3 The number of login attempts 261allowed before the backoff delay is inserted after each subsequent 262attempt. 263The backoff delay is the number of tries above 264.Em login-backoff 265multiplied by 5 seconds. 266.It "login-retries number 10 The number of login attempts 267allowed before the login fails. 268.It "passwd_format string md5 The encryption format that new or 269changed passwords will use. 270Valid values include "des", "md5" and "blf". 271NIS clients using a 272.No non- Ns Fx 273NIS server should probably use "des". 274.It "passwd_prompt string The password prompt presented by 275.Xr login 1 276.It "times.allow list List of time periods during which 277logins are allowed. 278.It "times.deny list List of time periods during which logins are 279disallowed. 280.It "ttys.allow list List of ttys and ttygroups which users 281in the class may use for access. 282.It "ttys.deny list List of ttys and ttygroups which users 283in the class may not use for access. 284.It "warnexpire time Advance notice for pending account expiry. 285.It "warnpassword time Advance notice for pending password expiry. 286.\".It "widepasswords bool false Use the wide password format. The wide password 287.\" format allows up to 128 significant characters in the password. 288.El 289.Pp 290These fields are intended to be used by 291.Xr passwd 1 292and other programs in the login authentication system. 293.Pp 294Capabilities that set environment variables are scanned for both 295.Ql \&~ 296and 297.Ql \&$ 298characters, which are substituted for a user's home directory and name 299respectively. 300To pass these characters literally into the environment variable, escape 301the character by preceding it with a backslash '\\'. 302.Pp 303The 304.Em host.allow 305and 306.Em host.deny 307entries are comma separated lists used for checking remote access to the system, 308and consist of a list of hostnames and/or IP addresses against which remote 309network logins are checked. 310Items in these lists may contain wildcards in the form used by shell programs 311for wildcard matching (See 312.Xr fnmatch 3 313for details on the implementation). 314The check on hosts is made against both the remote system's Internet address 315and hostname (if available). 316If both lists are empty or not specified, then logins from any remote host 317are allowed. 318If host.allow contains one or more hosts, then only remote systems matching 319any of the items in that list are allowed to log in. 320If host.deny contains one or more hosts, then a login from any matching hosts 321will be disallowed. 322.Pp 323The 324.Em times.allow 325and 326.Em times.deny 327entries consist of a comma-separated list of time periods during which the users 328in a class are allowed to be logged in. 329These are expressed as one or more day codes followed by a start and end times 330expressed in 24 hour format, separated by a hyphen or dash. 331For example, MoThSa0200-1300 translates to Monday, Thursday and Saturday between 332the hours of 2 am and 1 p.m.. 333If both of these time lists are empty, users in the class are allowed access at 334any time. 335If 336.Em times.allow 337is specified, then logins are only allowed during the periods given. 338If 339.Em times.deny 340is specified, then logins are denied during the periods given, regardless of whether 341one of the periods specified in 342.Em times.allow 343applies. 344.Pp 345Note that 346.Xr login 1 347enforces only that the actual login falls within periods allowed by these entries. 348Further enforcement over the life of a session requires a separate daemon to 349monitor transitions from an allowed period to a non-allowed one. 350.Pp 351The 352.Em ttys.allow 353and 354.Em ttys.deny 355entries contain a comma-separated list of tty devices (without the /dev/ prefix) 356that a user in a class may use to access the system, and/or a list of ttygroups 357(See 358.Xr getttyent 3 359and 360.Xr ttys 5 361for information on ttygroups). 362If neither entry exists, then the choice of login device used by the user is 363unrestricted. 364If only 365.Em ttys.allow 366is specified, then the user is restricted only to ttys in the given 367group or device list. 368If only 369.Em ttys.deny 370is specified, then the user is prevented from using the specified devices or 371devices in the group. 372If both lists are given and are non-empty, the user is restricted to those 373devices allowed by ttys.allow that are not available by ttys.deny. 374.Pp 375The 376.Em minpasswordlen 377and 378.Em minpasswordcase 379facilities for enforcing restrictions on password quality, which used 380to be supported by 381.Nm , 382have been superseded by the 383.Xr pam_passwdqc 8 384PAM module. 385.Sh RESERVED CAPABILITIES 386The following capabilities are reserved for the purposes indicated and 387may be supported by third-party software. 388They are not implemented in the base system. 389.Bl -column host.accounted indent indent 390.It Sy "Name Type Notes Description 391.It "accounted bool false Enable session time accounting for all users 392in this class. 393.It "auth list passwd Allowed authentication styles. 394The first item is the default style. 395.It "auth-" Ns Ar type Ta "list Allowed authentication styles for the 396authentication 397.Ar type . 398.It "autodelete time Time after expiry when account is auto-deleted. 399.It "bootfull bool false Enable 'boot only if ttygroup is full' strategy 400when terminating sessions. 401.It "daytime time Maximum login time per day. 402.It "expireperiod time Time for expiry allocation. 403.It "graceexpire time Grace days for expired account. 404.It "gracetime time Additional grace login time allowed. 405.It "host.accounted list List of remote host wildcards from which 406login sessions will be accounted. 407.It "host.exempt list List of remote host wildcards from which 408login session accounting is exempted. 409.It "idletime time Maximum idle time before logout. 410.It "minpasswordlen number 6 The minimum length a local 411password may be. 412.It "mixpasswordcase bool true Whether 413.Xr passwd 1 414will warn the user if an all lower case password is entered. 415.It "monthtime time Maximum login time per month. 416.It "passwordtime time Used by 417.Xr passwd 1 418to set next password expiry date. 419.It "refreshtime time New time allowed on account refresh. 420.It "refreshperiod str How often account time is refreshed. 421.It "sessiontime time Maximum login time per session. 422.It "sessionlimit number Maximum number of concurrent 423login sessions on ttys in any group. 424.It "ttys.accounted list List of ttys and ttygroups for which 425login accounting is active. 426.It "ttys.exempt list List of ttys and ttygroups for which login accounting 427is exempt. 428.It "warntime time Advance notice for pending out-of-time. 429.It "weektime time Maximum login time per week. 430.El 431.Pp 432The 433.Em ttys.accounted 434and 435.Em ttys.exempt 436fields operate in a similar manner to 437.Em ttys.allow 438and 439.Em ttys.deny 440as explained 441above. 442Similarly with the 443.Em host.accounted 444and 445.Em host.exempt 446lists. 447.Sh SEE ALSO 448.Xr cap_mkdb 1 , 449.Xr login 1 , 450.Xr chroot 2 , 451.Xr getcap 3 , 452.Xr getttyent 3 , 453.Xr login_cap 3 , 454.Xr login_class 3 , 455.Xr pam 3 , 456.Xr passwd 5 , 457.Xr ttys 5 , 458.Xr ftpd 8 , 459.Xr pam_passwdqc 8 460