diff options
Diffstat (limited to 'man/man5')
| -rw-r--r-- | man/man5/faillog.5 | 64 | ||||
| -rw-r--r-- | man/man5/gshadow.5 | 101 | ||||
| -rw-r--r-- | man/man5/limits.5 | 274 | ||||
| -rw-r--r-- | man/man5/login.access.5 | 67 | ||||
| -rw-r--r-- | man/man5/login.defs.5 | 872 | ||||
| -rw-r--r-- | man/man5/passwd.5 | 193 | ||||
| -rw-r--r-- | man/man5/porttime.5 | 96 | ||||
| -rw-r--r-- | man/man5/shadow.5 | 148 | ||||
| -rw-r--r-- | man/man5/suauth.5 | 146 | ||||
| -rw-r--r-- | man/man5/subgid.5 | 120 | ||||
| -rw-r--r-- | man/man5/subuid.5 | 120 |
11 files changed, 2201 insertions, 0 deletions
diff --git a/man/man5/faillog.5 b/man/man5/faillog.5 new file mode 100644 index 0000000..63a0df8 --- /dev/null +++ b/man/man5/faillog.5 @@ -0,0 +1,64 @@ +'\" t +.\" Title: faillog +.\" Author: Julianne Frances Haugh +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "FAILLOG" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuratio" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +faillog \- login failure logging file +.SH "DESCRIPTION" +.PP +/var/log/faillog +maintains a count of login failures and the limits for each account\&. +.PP +The file contains fixed length records, indexed by numerical UID\&. Each record contains the count of login failures since the last successful login; the maximum number of failures before the account is disabled; the line on which the last login failure occurred; the date of the last login failure; and the duration (in seconds) during which the account will be locked after a failure\&. +.PP +The structure of the file is: +.sp +.if n \{\ +.RS 4 +.\} +.nf +struct faillog { + short fail_cnt; + short fail_max; + char fail_line[12]; + time_t fail_time; + long fail_locktime; +}; +.fi +.if n \{\ +.RE +.\} +.SH "FILES" +.PP +/var/log/faillog +.RS 4 +Failure logging file\&. +.RE +.SH "SEE ALSO" +.PP +\fBfaillog\fR(8) diff --git a/man/man5/gshadow.5 b/man/man5/gshadow.5 new file mode 100644 index 0000000..663c4c3 --- /dev/null +++ b/man/man5/gshadow.5 @@ -0,0 +1,101 @@ +'\" t +.\" Title: gshadow +.\" Author: Nicolas François <nicolas.francois@centraliens.net> +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "GSHADOW" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +gshadow \- shadowed group file +.SH "DESCRIPTION" +.PP +/etc/gshadow +contains the shadowed information for group accounts\&. +.PP +This file must not be readable by regular users if password security is to be maintained\&. +.PP +Each line of this file contains the following colon\-separated fields: +.PP +\fBgroup name\fR +.RS 4 +It must be a valid group name, which exist on the system\&. +.RE +.PP +\fBencrypted password\fR +.RS 4 +Refer to +\fBcrypt\fR(3) +for details on how this string is interpreted\&. +.sp +If the password field contains some string that is not a valid result of +\fBcrypt\fR(3), for instance ! or *, users will not be able to use a unix password to access the group (but group members do not need the password)\&. +.sp +The password is used when a user who is not a member of the group wants to gain the permissions of this group (see +\fBnewgrp\fR(1))\&. +.sp +This field may be empty, in which case only the group members can gain the group permissions\&. +.sp +A password field which starts with an exclamation mark means that the password is locked\&. The remaining characters on the line represent the password field before the password was locked\&. +.sp +This password supersedes any password specified in +/etc/group\&. +.RE +.PP +\fBadministrators\fR +.RS 4 +It must be a comma\-separated list of user names\&. +.sp +Administrators can change the password or the members of the group\&. +.sp +Administrators also have the same permissions as the members (see below)\&. +.RE +.PP +\fBmembers\fR +.RS 4 +It must be a comma\-separated list of user names\&. +.sp +Members can access the group without being prompted for a password\&. +.sp +You should use the same list of users as in +/etc/group\&. +.RE +.SH "FILES" +.PP +/etc/group +.RS 4 +Group account information\&. +.RE +.PP +/etc/gshadow +.RS 4 +Secure group account information\&. +.RE +.SH "SEE ALSO" +.PP +\fBgpasswd\fR(5), +\fBgroup\fR(5), +\fBgrpck\fR(8), +\fBgrpconv\fR(8), +\fBnewgrp\fR(1)\&. diff --git a/man/man5/limits.5 b/man/man5/limits.5 new file mode 100644 index 0000000..46c5432 --- /dev/null +++ b/man/man5/limits.5 @@ -0,0 +1,274 @@ +'\" t +.\" Title: limits +.\" Author: Luca Berra +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "LIMITS" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +limits \- resource limits definition +.SH "DESCRIPTION" +.PP +The +\fIlimits\fR +file (/etc/limits +by default or LIMITS_FILE defined +config\&.h) describes the resource limits you wish to impose\&. It should be owned by root and readable by root account only\&. +.PP +By default no quota is imposed on \*(Aqroot\*(Aq\&. In fact, there is no way to impose limits via this procedure to root\-equiv accounts (accounts with UID 0)\&. +.PP +Each line describes a limit for a user in the form: +.PP +\fIuser LIMITS_STRING\fR +.PP +or in the form: +.PP +\fI@group LIMITS_STRING\fR +.PP +The +\fILIMITS_STRING\fR +is a string of a concatenated list of resource limits\&. Each limit consists of a letter identifier followed by a numerical limit\&. +.PP +The valid identifiers are: +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +A: max address space (KB) +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +C: max core file size (KB) +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +D: max data size (KB) +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +F: maximum file size (KB) +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +K: file creation mask, set by +\fBumask\fR(2)\&. +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +I: max nice value (0\&.\&.39 which translates to 20\&.\&.\-19) +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +L: max number of logins for this user +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +M: max locked\-in\-memory address space (KB) +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +N: max number of open files +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +O: max real time priority +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +P: process priority, set by +\fBsetpriority\fR(2)\&. +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +R: max resident set size (KB) +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +S: max stack size (KB) +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +T: max CPU time (MIN) +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +U: max number of processes +.RE +.PP +For example, +\fIL2D2048N5\fR +is a valid +\fILIMITS_STRING\fR\&. For reading convenience, the following entries are equivalent: +.sp +.if n \{\ +.RS 4 +.\} +.nf + username L2D2048N5 + username L2 D2048 N5 + +.fi +.if n \{\ +.RE +.\} +.PP +Be aware that after +\fIusername\fR +the rest of the line is considered a limit string, thus comments are not allowed\&. An invalid limits string will be rejected (not considered) by the +\fBlogin\fR +program\&. +.PP +The default entry is denoted by username "\fI*\fR"\&. If you have multiple +\fIdefault\fR +entries in your +\fILIMITS_FILE\fR, then the last one will be used as the default entry\&. +.PP +The limits specified in the form "\fI@group\fR" apply to the members of the specified +\fIgroup\fR\&. +.PP +If more than one line with limits for a user exist, only the first line for this user will be considered\&. +.PP +If no lines are specified for a user, the last +\fI@group\fR +line matching a group whose the user is a member of will be considered, or the last line with default limits if no groups contain the user\&. +.PP +To completely disable limits for a user, a single dash "\fI\-\fR" will do\&. +.PP +To disable a limit for a user, a single dash "\fI\-\fR" can be used instead of the numerical value for this limit\&. +.PP +Also, please note that all limit settings are set PER LOGIN\&. They are not global, nor are they permanent\&. Perhaps global limits will come, but for now this will have to do ;) +.SH "FILES" +.PP +/etc/limits +.RS 4 +.RE +.SH "SEE ALSO" +.PP +\fBlogin\fR(1), +\fBsetpriority\fR(2), +\fBsetrlimit\fR(2)\&. diff --git a/man/man5/login.access.5 b/man/man5/login.access.5 new file mode 100644 index 0000000..37d57b2 --- /dev/null +++ b/man/man5/login.access.5 @@ -0,0 +1,67 @@ +'\" t +.\" Title: login.access +.\" Author: Marek Michałkiewicz +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "LOGIN\&.ACCESS" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +login.access \- login access control table +.SH "DESCRIPTION" +.PP +The +\fIlogin\&.access\fR +file specifies (user, host) combinations and/or (user, tty) combinations for which a login will be either accepted or refused\&. +.PP +When someone logs in, the +\fIlogin\&.access\fR +is scanned for the first entry that matches the (user, host) combination, or, in case of non\-networked logins, the first entry that matches the (user, tty) combination\&. The permissions field of that table entry determines whether the login will be accepted or refused\&. +.PP +Each line of the login access control table has three fields separated by a ":" character: +.PP +\fIpermission\fR:\fIusers\fR:\fIorigins\fR +.PP +The first field should be a "\fI+\fR" (access granted) or "\fI\-\fR" (access denied) character\&. The second field should be a list of one or more login names, group names, or +\fIALL\fR +(always matches)\&. The third field should be a list of one or more tty names (for non\-networked logins), host names, domain names (begin with "\&."), host addresses, internet network numbers (end with "\&."), +\fIALL\fR +(always matches) or +\fILOCAL\fR +(matches any string that does not contain a "\&." character)\&. If you run NIS you can use @netgroupname in host or user patterns\&. +.PP +The +\fIEXCEPT\fR +operator makes it possible to write very compact rules\&. +.PP +The group file is searched only when a name does not match that of the logged\-in user\&. Only groups are matched in which users are explicitly listed: the program does not look at a user\*(Aqs primary group id value\&. +.SH "FILES" +.PP +/etc/login\&.defs +.RS 4 +Shadow password suite configuration\&. +.RE +.SH "SEE ALSO" +.PP +\fBlogin\fR(1)\&. diff --git a/man/man5/login.defs.5 b/man/man5/login.defs.5 new file mode 100644 index 0000000..350870e --- /dev/null +++ b/man/man5/login.defs.5 @@ -0,0 +1,872 @@ +'\" t +.\" Title: login.defs +.\" Author: Julianne Frances Haugh +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "LOGIN\&.DEFS" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +login.defs \- shadow password suite configuration +.SH "DESCRIPTION" +.PP +The +/etc/login\&.defs +file defines the site\-specific configuration for the shadow password suite\&. This file is required\&. Absence of this file will not prevent system operation, but will probably result in undesirable operation\&. +.PP +This file is a readable text file, each line of the file describing one configuration parameter\&. The lines consist of a configuration name and value, separated by whitespace\&. Blank lines and comment lines are ignored\&. Comments are introduced with a "#" pound sign and the pound sign must be the first non\-white character of the line\&. +.PP +Parameter values may be of four types: strings, booleans, numbers, and long numbers\&. A string is comprised of any printable characters\&. A boolean should be either the value +\fIyes\fR +or +\fIno\fR\&. An undefined boolean parameter or one with a value other than these will be given a +\fIno\fR +value\&. Numbers (both regular and long) may be either decimal values, octal values (precede the value with +\fI0\fR) or hexadecimal values (precede the value with +\fI0x\fR)\&. The maximum value of the regular and long numeric parameters is machine\-dependent\&. +.PP +The following configuration items are provided: +.PP +\fBCHFN_AUTH\fR (boolean) +.RS 4 +If +\fIyes\fR, the +\fBchfn\fR +program will require authentication before making any changes, unless run by the superuser\&. +.RE +.PP +\fBCHFN_RESTRICT\fR (string) +.RS 4 +This parameter specifies which values in the +\fIgecos\fR +field of the +/etc/passwd +file may be changed by regular users using the +\fBchfn\fR +program\&. It can be any combination of letters +\fIf\fR, +\fIr\fR, +\fIw\fR, +\fIh\fR, for Full name, Room number, Work phone, and Home phone, respectively\&. For backward compatibility, +\fIyes\fR +is equivalent to +\fIrwh\fR +and +\fIno\fR +is equivalent to +\fIfrwh\fR\&. If not specified, only the superuser can make any changes\&. The most restrictive setting is better achieved by not installing +\fBchfn\fR +SUID\&. +.RE +.PP +\fBCHSH_AUTH\fR (boolean) +.RS 4 +If +\fIyes\fR, the +\fBchsh\fR +program will require authentication before making any changes, unless run by the superuser\&. +.RE +.PP +\fBCONSOLE\fR (string) +.RS 4 +If defined, either full pathname of a file containing device names (one per line) or a ":" delimited list of device names\&. Root logins will be allowed only upon these devices\&. +.sp +If not defined, root will be allowed on any device\&. +.sp +The device should be specified without the /dev/ prefix\&. +.RE +.PP +\fBCONSOLE_GROUPS\fR (string) +.RS 4 +List of groups to add to the user\*(Aqs supplementary groups set when logging in on the console (as determined by the CONSOLE setting)\&. Default is none\&. + +Use with caution \- it is possible for users to gain permanent access to these groups, even when not logged in on the console\&. +.RE +.PP +\fBCREATE_HOME\fR (boolean) +.RS 4 +Indicate if a home directory should be created by default for new users\&. +.sp +This setting does not apply to system users, and can be overridden on the command line\&. +.RE +.PP +\fBDEFAULT_HOME\fR (boolean) +.RS 4 +Indicate if login is allowed if we can\*(Aqt cd to the home directory\&. Default is no\&. +.sp +If set to +\fIyes\fR, the user will login in the root (/) directory if it is not possible to cd to her home directory\&. +.RE +.PP +\fBENCRYPT_METHOD\fR (string) +.RS 4 +This defines the system default encryption algorithm for encrypting passwords (if no algorithm are specified on the command line)\&. +.sp +It can take one of these values: +\fIDES\fR +(default), +\fIMD5\fR, \fISHA256\fR, \fISHA512\fR\&. MD5 and DES should not be used for new hashes, see +crypt(5) +for recommendations\&. +.sp +Note: this parameter overrides the +\fBMD5_CRYPT_ENAB\fR +variable\&. +.RE +.PP +\fBENV_HZ\fR (string) +.RS 4 +If set, it will be used to define the HZ environment variable when a user login\&. The value must be preceded by +\fIHZ=\fR\&. A common value on Linux is +\fIHZ=100\fR\&. +.RE +.PP +\fBENV_PATH\fR (string) +.RS 4 +If set, it will be used to define the PATH environment variable when a regular user login\&. The value is a colon separated list of paths (for example +\fI/bin:/usr/bin\fR) and can be preceded by +\fIPATH=\fR\&. The default value is +\fIPATH=/bin:/usr/bin\fR\&. +.RE +.PP +\fBENV_SUPATH\fR (string) +.RS 4 +If set, it will be used to define the PATH environment variable when the superuser login\&. The value is a colon separated list of paths (for example +\fI/sbin:/bin:/usr/sbin:/usr/bin\fR) and can be preceded by +\fIPATH=\fR\&. The default value is +\fIPATH=/sbin:/bin:/usr/sbin:/usr/bin\fR\&. +.RE +.PP +\fBENV_TZ\fR (string) +.RS 4 +If set, it will be used to define the TZ environment variable when a user login\&. The value can be the name of a timezone preceded by +\fITZ=\fR +(for example +\fITZ=CST6CDT\fR), or the full path to the file containing the timezone specification (for example +/etc/tzname)\&. +.sp +If a full path is specified but the file does not exist or cannot be read, the default is to use +\fITZ=CST6CDT\fR\&. +.RE +.PP +\fBENVIRON_FILE\fR (string) +.RS 4 +If this file exists and is readable, login environment will be read from it\&. Every line should be in the form name=value\&. +.sp +Lines starting with a # are treated as comment lines and ignored\&. +.RE +.PP +\fBERASECHAR\fR (number) +.RS 4 +Terminal ERASE character (\fI010\fR += backspace, +\fI0177\fR += DEL)\&. +.sp +The value can be prefixed "0" for an octal value, or "0x" for an hexadecimal value\&. +.RE +.PP +\fBFAIL_DELAY\fR (number) +.RS 4 +Delay in seconds before being allowed another attempt after a login failure\&. +.RE +.PP +\fBFAILLOG_ENAB\fR (boolean) +.RS 4 +Enable logging and display of +/var/log/faillog +login failure info\&. +.RE +.PP +\fBFAKE_SHELL\fR (string) +.RS 4 +If set, +\fBlogin\fR +will execute this shell instead of the users\*(Aq shell specified in +/etc/passwd\&. +.RE +.PP +\fBFTMP_FILE\fR (string) +.RS 4 +If defined, login failures will be logged in this file in a utmp format\&. +.RE +.PP +\fBGID_MAX\fR (number), \fBGID_MIN\fR (number) +.RS 4 +Range of group IDs used for the creation of regular groups by +\fBuseradd\fR, +\fBgroupadd\fR, or +\fBnewusers\fR\&. +.sp +The default value for +\fBGID_MIN\fR +(resp\&. +\fBGID_MAX\fR) is 1000 (resp\&. 60000)\&. +.RE +.PP +\fBHMAC_CRYPTO_ALGO\fR (string) +.RS 4 +Used to select the HMAC cryptography algorithm that the pam_timestamp module is going to use to calculate the keyed\-hash message authentication code\&. +.sp +Note: Check +hmac(3) +to see the possible algorithms that are available in your system\&. +.RE +.PP +\fBHOME_MODE\fR (number) +.RS 4 +The mode for new home directories\&. If not specified, the +\fBUMASK\fR +is used to create the mode\&. +.sp +\fBuseradd\fR +and +\fBnewusers\fR +use this to set the mode of the home directory they create\&. +.RE +.PP +\fBHUSHLOGIN_FILE\fR (string) +.RS 4 +If defined, this file can inhibit all the usual chatter during the login sequence\&. If a full pathname is specified, then hushed mode will be enabled if the user\*(Aqs name or shell are found in the file\&. If not a full pathname, then hushed mode will be enabled if the file exists in the user\*(Aqs home directory\&. +.RE +.PP +\fBISSUE_FILE\fR (string) +.RS 4 +If defined, this file will be displayed before each login prompt\&. +.RE +.PP +\fBKILLCHAR\fR (number) +.RS 4 +Terminal KILL character (\fI025\fR += CTRL/U)\&. +.sp +The value can be prefixed "0" for an octal value, or "0x" for an hexadecimal value\&. +.RE +.PP +\fBLASTLOG_ENAB\fR (boolean) +.RS 4 +Enable logging and display of /var/log/lastlog login time info\&. +.RE +.PP +\fBLASTLOG_UID_MAX\fR (number) +.RS 4 +Highest user ID number for which the lastlog entries should be updated\&. As higher user IDs are usually tracked by remote user identity and authentication services there is no need to create a huge sparse lastlog file for them\&. +.sp +No +\fBLASTLOG_UID_MAX\fR +option present in the configuration means that there is no user ID limit for writing lastlog entries\&. +.RE +.PP +\fBLOG_OK_LOGINS\fR (boolean) +.RS 4 +Enable logging of successful logins\&. +.RE +.PP +\fBLOG_UNKFAIL_ENAB\fR (boolean) +.RS 4 +Enable display of unknown usernames when login failures are recorded\&. +.sp +Note: logging unknown usernames may be a security issue if an user enter her password instead of her login name\&. +.RE +.PP +\fBLOGIN_RETRIES\fR (number) +.RS 4 +Maximum number of login retries in case of bad password\&. +.RE +.PP +\fBLOGIN_STRING\fR (string) +.RS 4 +The string used for prompting a password\&. The default is to use "Password: ", or a translation of that string\&. If you set this variable, the prompt will not be translated\&. +.sp +If the string contains +\fI%s\fR, this will be replaced by the user\*(Aqs name\&. +.RE +.PP +\fBLOGIN_TIMEOUT\fR (number) +.RS 4 +Max time in seconds for login\&. +.RE +.PP +\fBMAIL_CHECK_ENAB\fR (boolean) +.RS 4 +Enable checking and display of mailbox status upon login\&. +.sp +You should disable it if the shell startup files already check for mail ("mailx \-e" or equivalent)\&. +.RE +.PP +\fBMAIL_DIR\fR (string) +.RS 4 +The mail spool directory\&. This is needed to manipulate the mailbox when its corresponding user account is modified or deleted\&. If not specified, a compile\-time default is used\&. The parameter CREATE_MAIL_SPOOL in +/etc/default/useradd +determines whether the mail spool should be created\&. +.RE +.PP +\fBMAIL_FILE\fR (string) +.RS 4 +Defines the location of the users mail spool files relatively to their home directory\&. +.RE +.PP +The +\fBMAIL_DIR\fR +and +\fBMAIL_FILE\fR +variables are used by +\fBuseradd\fR, +\fBusermod\fR, and +\fBuserdel\fR +to create, move, or delete the user\*(Aqs mail spool\&. +.PP +If +\fBMAIL_CHECK_ENAB\fR +is set to +\fIyes\fR, they are also used to define the +\fBMAIL\fR +environment variable\&. +.PP +\fBMAX_MEMBERS_PER_GROUP\fR (number) +.RS 4 +Maximum members per group entry\&. When the maximum is reached, a new group entry (line) is started in +/etc/group +(with the same name, same password, and same GID)\&. +.sp +The default value is 0, meaning that there are no limits in the number of members in a group\&. +.sp +This feature (split group) permits to limit the length of lines in the group file\&. This is useful to make sure that lines for NIS groups are not larger than 1024 characters\&. +.sp +If you need to enforce such limit, you can use 25\&. +.sp +Note: split groups may not be supported by all tools (even in the Shadow toolsuite)\&. You should not use this variable unless you really need it\&. +.RE +.PP +\fBMD5_CRYPT_ENAB\fR (boolean) +.RS 4 +Indicate if passwords must be encrypted using the MD5\-based algorithm\&. If set to +\fIyes\fR, new passwords will be encrypted using the MD5\-based algorithm compatible with the one used by recent releases of FreeBSD\&. It supports passwords of unlimited length and longer salt strings\&. Set to +\fIno\fR +if you need to copy encrypted passwords to other systems which don\*(Aqt understand the new algorithm\&. Default is +\fIno\fR\&. +.sp +This variable is superseded by the +\fBENCRYPT_METHOD\fR +variable or by any command line option used to configure the encryption algorithm\&. +.sp +This variable is deprecated\&. You should use +\fBENCRYPT_METHOD\fR\&. +.RE +.PP +\fBMOTD_FILE\fR (string) +.RS 4 +If defined, ":" delimited list of "message of the day" files to be displayed upon login\&. +.RE +.PP +\fBNOLOGINS_FILE\fR (string) +.RS 4 +If defined, name of file whose presence will inhibit non\-root logins\&. The contents of this file should be a message indicating why logins are inhibited\&. +.RE +.PP +\fBNONEXISTENT\fR (string) +.RS 4 +If a system account intentionally does not have a home directory that exists, this string can be provided in the /etc/passwd entry for the account to indicate this\&. The result is that pwck will not emit a spurious warning for this account\&. +.RE +.PP +\fBOBSCURE_CHECKS_ENAB\fR (boolean) +.RS 4 +Enable additional checks upon password changes\&. +.RE +.PP +\fBPASS_ALWAYS_WARN\fR (boolean) +.RS 4 +Warn about weak passwords (but still allow them) if you are root\&. +.RE +.PP +\fBPASS_CHANGE_TRIES\fR (number) +.RS 4 +Maximum number of attempts to change password if rejected (too easy)\&. +.RE +.PP +\fBPASS_MAX_DAYS\fR (number) +.RS 4 +The maximum number of days a password may be used\&. If the password is older than this, a password change will be forced\&. If not specified, \-1 will be assumed (which disables the restriction)\&. +.RE +.PP +\fBPASS_MIN_DAYS\fR (number) +.RS 4 +The minimum number of days allowed between password changes\&. Any password changes attempted sooner than this will be rejected\&. If not specified, 0 will be assumed (which disables the restriction)\&. +.RE +.PP +\fBPASS_WARN_AGE\fR (number) +.RS 4 +The number of days warning given before a password expires\&. A zero means warning is given only upon the day of expiration, a negative value means no warning is given\&. If not specified, no warning will be provided\&. +.RE +.PP +\fBPASS_MAX_DAYS\fR, +\fBPASS_MIN_DAYS\fR +and +\fBPASS_WARN_AGE\fR +are only used at the time of account creation\&. Any changes to these settings won\*(Aqt affect existing accounts\&. +.PP +\fBPASS_MAX_LEN\fR (number), \fBPASS_MIN_LEN\fR (number) +.RS 4 +Number of significant characters in the password for crypt()\&. +\fBPASS_MAX_LEN\fR +is 8 by default\&. Don\*(Aqt change unless your crypt() is better\&. This is ignored if +\fBMD5_CRYPT_ENAB\fR +set to +\fIyes\fR\&. +.RE +.PP +\fBPORTTIME_CHECKS_ENAB\fR (boolean) +.RS 4 +Enable checking of time restrictions specified in +/etc/porttime\&. +.RE +.PP +\fBQUOTAS_ENAB\fR (boolean) +.RS 4 +Enable setting of resource limits from +/etc/limits +and ulimit, umask, and niceness from the user\*(Aqs passwd gecos field\&. +.RE +.PP +\fBSHA_CRYPT_MIN_ROUNDS\fR (number), \fBSHA_CRYPT_MAX_ROUNDS\fR (number) +.RS 4 +When +\fBENCRYPT_METHOD\fR +is set to +\fISHA256\fR +or +\fISHA512\fR, this defines the number of SHA rounds used by the encryption algorithm by default (when the number of rounds is not specified on the command line)\&. +.sp +With a lot of rounds, it is more difficult to brute forcing the password\&. But note also that more CPU resources will be needed to authenticate users\&. +.sp +If not specified, the libc will choose the default number of rounds (5000), which is orders of magnitude too low for modern hardware\&. +.sp +The values must be inside the 1000\-999,999,999 range\&. +.sp +If only one of the +\fBSHA_CRYPT_MIN_ROUNDS\fR +or +\fBSHA_CRYPT_MAX_ROUNDS\fR +values is set, then this value will be used\&. +.sp +If +\fBSHA_CRYPT_MIN_ROUNDS\fR +> +\fBSHA_CRYPT_MAX_ROUNDS\fR, the highest value will be used\&. +.RE +.PP +\fBSULOG_FILE\fR (string) +.RS 4 +If defined, all su activity is logged to this file\&. +.RE +.PP +\fBSU_NAME\fR (string) +.RS 4 +If defined, the command name to display when running "su \-"\&. For example, if this is defined as "su" then a "ps" will display the command is "\-su"\&. If not defined, then "ps" would display the name of the shell actually being run, e\&.g\&. something like "\-sh"\&. +.RE +.PP +\fBSU_WHEEL_ONLY\fR (boolean) +.RS 4 +If +\fIyes\fR, the user must be listed as a member of the first gid 0 group in +/etc/group +(called +\fIroot\fR +on most Linux systems) to be able to +\fBsu\fR +to uid 0 accounts\&. If the group doesn\*(Aqt exist or is empty, no one will be able to +\fBsu\fR +to uid 0\&. +.RE +.PP +\fBSUB_GID_MIN\fR (number), \fBSUB_GID_MAX\fR (number), \fBSUB_GID_COUNT\fR (number) +.RS 4 +If +/etc/subuid +exists, the commands +\fBuseradd\fR +and +\fBnewusers\fR +(unless the user already have subordinate group IDs) allocate +\fBSUB_GID_COUNT\fR +unused group IDs from the range +\fBSUB_GID_MIN\fR +to +\fBSUB_GID_MAX\fR +for each new user\&. +.sp +The default values for +\fBSUB_GID_MIN\fR, +\fBSUB_GID_MAX\fR, +\fBSUB_GID_COUNT\fR +are respectively 100000, 600100000 and 65536\&. +.RE +.PP +\fBSUB_UID_MIN\fR (number), \fBSUB_UID_MAX\fR (number), \fBSUB_UID_COUNT\fR (number) +.RS 4 +If +/etc/subuid +exists, the commands +\fBuseradd\fR +and +\fBnewusers\fR +(unless the user already have subordinate user IDs) allocate +\fBSUB_UID_COUNT\fR +unused user IDs from the range +\fBSUB_UID_MIN\fR +to +\fBSUB_UID_MAX\fR +for each new user\&. +.sp +The default values for +\fBSUB_UID_MIN\fR, +\fBSUB_UID_MAX\fR, +\fBSUB_UID_COUNT\fR +are respectively 100000, 600100000 and 65536\&. +.RE +.PP +\fBSYS_GID_MAX\fR (number), \fBSYS_GID_MIN\fR (number) +.RS 4 +Range of group IDs used for the creation of system groups by +\fBuseradd\fR, +\fBgroupadd\fR, or +\fBnewusers\fR\&. +.sp +The default value for +\fBSYS_GID_MIN\fR +(resp\&. +\fBSYS_GID_MAX\fR) is 101 (resp\&. +\fBGID_MIN\fR\-1)\&. +.RE +.PP +\fBSYS_UID_MAX\fR (number), \fBSYS_UID_MIN\fR (number) +.RS 4 +Range of user IDs used for the creation of system users by +\fBuseradd\fR +or +\fBnewusers\fR\&. +.sp +The default value for +\fBSYS_UID_MIN\fR +(resp\&. +\fBSYS_UID_MAX\fR) is 101 (resp\&. +\fBUID_MIN\fR\-1)\&. +.RE +.PP +\fBSYSLOG_SG_ENAB\fR (boolean) +.RS 4 +Enable "syslog" logging of +\fBsg\fR +activity\&. +.RE +.PP +\fBSYSLOG_SU_ENAB\fR (boolean) +.RS 4 +Enable "syslog" logging of +\fBsu\fR +activity \- in addition to sulog file logging\&. +.RE +.PP +\fBTTYGROUP\fR (string), \fBTTYPERM\fR (string) +.RS 4 +The terminal permissions: the login tty will be owned by the +\fBTTYGROUP\fR +group, and the permissions will be set to +\fBTTYPERM\fR\&. +.sp +By default, the ownership of the terminal is set to the user\*(Aqs primary group and the permissions are set to +\fI0600\fR\&. +.sp +\fBTTYGROUP\fR +can be either the name of a group or a numeric group identifier\&. +.sp +If you have a +\fBwrite\fR +program which is "setgid" to a special group which owns the terminals, define TTYGROUP to the group number and TTYPERM to 0620\&. Otherwise leave TTYGROUP commented out and assign TTYPERM to either 622 or 600\&. +.RE +.PP +\fBTTYTYPE_FILE\fR (string) +.RS 4 +If defined, file which maps tty line to TERM environment parameter\&. Each line of the file is in a format something like "vt100 tty01"\&. +.RE +.PP +\fBUID_MAX\fR (number), \fBUID_MIN\fR (number) +.RS 4 +Range of user IDs used for the creation of regular users by +\fBuseradd\fR +or +\fBnewusers\fR\&. +.sp +The default value for +\fBUID_MIN\fR +(resp\&. +\fBUID_MAX\fR) is 1000 (resp\&. 60000)\&. +.RE +.PP +\fBULIMIT\fR (number) +.RS 4 +Default +\fBulimit\fR +value\&. +.RE +.PP +\fBUMASK\fR (number) +.RS 4 +The file mode creation mask is initialized to this value\&. If not specified, the mask will be initialized to 022\&. +.sp +\fBuseradd\fR +and +\fBnewusers\fR +use this mask to set the mode of the home directory they create if +\fBHOME_MODE\fR +is not set\&. +.sp +It is also used by +\fBlogin\fR +to define users\*(Aq initial umask\&. Note that this mask can be overridden by the user\*(Aqs GECOS line (if +\fBQUOTAS_ENAB\fR +is set) or by the specification of a limit with the +\fIK\fR +identifier in +\fBlimits\fR(5)\&. +.RE +.PP +\fBUSERDEL_CMD\fR (string) +.RS 4 +If defined, this command is run when removing a user\&. It should remove any at/cron/print jobs etc\&. owned by the user to be removed (passed as the first argument)\&. +.sp +The return code of the script is not taken into account\&. +.sp +Here is an example script, which removes the user\*(Aqs cron, at and print jobs: +.sp +.if n \{\ +.RS 4 +.\} +.nf +#! /bin/sh + +# Check for the required argument\&. +if [ $# != 1 ]; then + echo "Usage: $0 username" + exit 1 +fi + +# Remove cron jobs\&. +crontab \-r \-u $1 + +# Remove at jobs\&. +# Note that it will remove any jobs owned by the same UID, +# even if it was shared by a different username\&. +AT_SPOOL_DIR=/var/spool/cron/atjobs +find $AT_SPOOL_DIR \-name "[^\&.]*" \-type f \-user $1 \-delete \e; + +# Remove print jobs\&. +lprm $1 + +# All done\&. +exit 0 + +.fi +.if n \{\ +.RE +.\} +.sp +.RE +.PP +\fBUSERGROUPS_ENAB\fR (boolean) +.RS 4 +Enable setting of the umask group bits to be the same as owner bits (examples: 022 \-> 002, 077 \-> 007) for non\-root users, if the uid is the same as gid, and username is the same as the primary group name\&. +.sp +If set to +\fIyes\fR, +\fBuserdel\fR +will remove the user\*(Aqs group if it contains no more members, and +\fBuseradd\fR +will create by default a group with the name of the user\&. +.RE +.SH "CROSS REFERENCES" +.PP +The following cross references show which programs in the shadow password suite use which parameters\&. +.PP +chfn +.RS 4 +CHFN_AUTH +CHFN_RESTRICT +LOGIN_STRING +.RE +.PP +chgpasswd +.RS 4 +ENCRYPT_METHOD MAX_MEMBERS_PER_GROUP MD5_CRYPT_ENAB +SHA_CRYPT_MAX_ROUNDS SHA_CRYPT_MIN_ROUNDS +.RE +.PP +chpasswd +.RS 4 +ENCRYPT_METHOD MD5_CRYPT_ENAB +SHA_CRYPT_MAX_ROUNDS SHA_CRYPT_MIN_ROUNDS +.RE +.PP +chsh +.RS 4 +CHSH_AUTH LOGIN_STRING +.RE +.PP +gpasswd +.RS 4 +ENCRYPT_METHOD MAX_MEMBERS_PER_GROUP MD5_CRYPT_ENAB +SHA_CRYPT_MAX_ROUNDS SHA_CRYPT_MIN_ROUNDS +.RE +.PP +groupadd +.RS 4 +GID_MAX GID_MIN MAX_MEMBERS_PER_GROUP SYS_GID_MAX SYS_GID_MIN +.RE +.PP +groupdel +.RS 4 +MAX_MEMBERS_PER_GROUP +.RE +.PP +groupmems +.RS 4 +MAX_MEMBERS_PER_GROUP +.RE +.PP +groupmod +.RS 4 +MAX_MEMBERS_PER_GROUP +.RE +.PP +grpck +.RS 4 +MAX_MEMBERS_PER_GROUP +.RE +.PP +grpconv +.RS 4 +MAX_MEMBERS_PER_GROUP +.RE +.PP +grpunconv +.RS 4 +MAX_MEMBERS_PER_GROUP +.RE +.PP +lastlog +.RS 4 +LASTLOG_UID_MAX +.RE +.PP +login +.RS 4 +CONSOLE +CONSOLE_GROUPS DEFAULT_HOME +ENV_HZ ENV_PATH ENV_SUPATH ENV_TZ ENVIRON_FILE +ERASECHAR FAIL_DELAY +FAILLOG_ENAB +FAKE_SHELL +FTMP_FILE +HUSHLOGIN_FILE +ISSUE_FILE +KILLCHAR +LASTLOG_ENAB LASTLOG_UID_MAX +LOGIN_RETRIES +LOGIN_STRING +LOGIN_TIMEOUT LOG_OK_LOGINS LOG_UNKFAIL_ENAB +MAIL_CHECK_ENAB MAIL_DIR MAIL_FILE MOTD_FILE NOLOGINS_FILE PORTTIME_CHECKS_ENAB QUOTAS_ENAB +TTYGROUP TTYPERM TTYTYPE_FILE +ULIMIT UMASK +USERGROUPS_ENAB +.RE +.PP +newgrp / sg +.RS 4 +SYSLOG_SG_ENAB +.RE +.PP +newusers +.RS 4 +ENCRYPT_METHOD GID_MAX GID_MIN MAX_MEMBERS_PER_GROUP MD5_CRYPT_ENAB HOME_MODE PASS_MAX_DAYS PASS_MIN_DAYS PASS_WARN_AGE +SHA_CRYPT_MAX_ROUNDS SHA_CRYPT_MIN_ROUNDS +SUB_GID_COUNT SUB_GID_MAX SUB_GID_MIN SUB_UID_COUNT SUB_UID_MAX SUB_UID_MIN SYS_GID_MAX SYS_GID_MIN SYS_UID_MAX SYS_UID_MIN UID_MAX UID_MIN UMASK +.RE +.PP +passwd +.RS 4 +ENCRYPT_METHOD MD5_CRYPT_ENAB OBSCURE_CHECKS_ENAB PASS_ALWAYS_WARN PASS_CHANGE_TRIES PASS_MAX_LEN PASS_MIN_LEN +SHA_CRYPT_MAX_ROUNDS SHA_CRYPT_MIN_ROUNDS +.RE +.PP +pwck +.RS 4 +PASS_MAX_DAYS PASS_MIN_DAYS PASS_WARN_AGE +.RE +.PP +pwconv +.RS 4 +PASS_MAX_DAYS PASS_MIN_DAYS PASS_WARN_AGE +.RE +.PP +su +.RS 4 +CONSOLE +CONSOLE_GROUPS DEFAULT_HOME +ENV_HZ ENVIRON_FILE +ENV_PATH ENV_SUPATH +ENV_TZ LOGIN_STRING MAIL_CHECK_ENAB MAIL_DIR MAIL_FILE QUOTAS_ENAB +SULOG_FILE SU_NAME +SU_WHEEL_ONLY +SYSLOG_SU_ENAB +USERGROUPS_ENAB +.RE +.PP +sulogin +.RS 4 +ENV_HZ +ENV_TZ +.RE +.PP +useradd +.RS 4 +CREATE_HOME GID_MAX GID_MIN HOME_MODE LASTLOG_UID_MAX MAIL_DIR MAX_MEMBERS_PER_GROUP PASS_MAX_DAYS PASS_MIN_DAYS PASS_WARN_AGE SUB_GID_COUNT SUB_GID_MAX SUB_GID_MIN SUB_UID_COUNT SUB_UID_MAX SUB_UID_MIN SYS_GID_MAX SYS_GID_MIN SYS_UID_MAX SYS_UID_MIN UID_MAX UID_MIN UMASK +.RE +.PP +userdel +.RS 4 +MAIL_DIR MAIL_FILE MAX_MEMBERS_PER_GROUP USERDEL_CMD USERGROUPS_ENAB +.RE +.PP +usermod +.RS 4 +LASTLOG_UID_MAX MAIL_DIR MAIL_FILE MAX_MEMBERS_PER_GROUP +.RE +.SH "SEE ALSO" +.PP +\fBlogin\fR(1), +\fBpasswd\fR(1), +\fBsu\fR(1), +\fBpasswd\fR(5), +\fBshadow\fR(5), +\fBpam\fR(8)\&. diff --git a/man/man5/passwd.5 b/man/man5/passwd.5 new file mode 100644 index 0000000..d1171d3 --- /dev/null +++ b/man/man5/passwd.5 @@ -0,0 +1,193 @@ +'\" t +.\" Title: passwd +.\" Author: Julianne Frances Haugh +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "PASSWD" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +passwd \- the password file +.SH "DESCRIPTION" +.PP +/etc/passwd +contains one line for each user account, with seven fields delimited by colons (\(lq:\(rq)\&. These fields are: +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +login name +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +optional encrypted password +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +numerical user ID +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +numerical group ID +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +user name or comment field +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +user home directory +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +optional user command interpreter +.RE +.PP +If the +\fIpassword\fR +field is a lower\-case +\(lqx\(rq, then the encrypted password is actually stored in the +\fBshadow\fR(5) +file instead; there +\fImust\fR +be a corresponding line in the +/etc/shadow +file, or else the user account is invalid\&. +.PP +The encrypted +\fIpassword\fR +field may be empty, in which case no password is required to authenticate as the specified login name\&. However, some applications which read the +/etc/passwd +file may decide not to permit +\fIany\fR +access at all if the +\fIpassword\fR +field is blank\&. +.PP +A +\fIpassword\fR +field which starts with an exclamation mark means that the password is locked\&. The remaining characters on the line represent the +\fIpassword\fR +field before the password was locked\&. +.PP +Refer to +\fBcrypt\fR(3) +for details on how this string is interpreted\&. +.PP +If the password field contains some string that is not a valid result of +\fBcrypt\fR(3), for instance ! or *, the user will not be able to use a unix password to log in (but the user may log in the system by other means)\&. +.PP +The comment field, also known as the gecos field, is used by various system utilities, such as +\fBfinger\fR(1)\&. The use of an ampersand here will be replaced by the capitalised login name when the field is used or displayed by such system utilities\&. +.PP +The home directory field provides the name of the initial working directory\&. The +\fBlogin\fR +program uses this information to set the value of the +\fB$HOME\fR +environmental variable\&. +.PP +The command interpreter field provides the name of the user\*(Aqs command language interpreter, or the name of the initial program to execute\&. The +\fBlogin\fR +program uses this information to set the value of the +\fB$SHELL\fR +environmental variable\&. If this field is empty, it defaults to the value +/bin/sh\&. +.SH "FILES" +.PP +/etc/passwd +.RS 4 +User account information\&. +.RE +.PP +/etc/shadow +.RS 4 +optional encrypted password file +.RE +.PP +/etc/passwd\- +.RS 4 +Backup file for /etc/passwd\&. +.sp +Note that this file is used by the tools of the shadow toolsuite, but not by all user and password management tools\&. +.RE +.SH "SEE ALSO" +.PP +\fBcrypt\fR(3), +\fBgetent\fR(1), +\fBgetpwnam\fR(3), +\fBlogin\fR(1), +\fBpasswd\fR(1), +\fBpwck\fR(8), +\fBpwconv\fR(8), +\fBpwunconv\fR(8), +\fBshadow\fR(5), +\fBsu\fR(1), +\fBsulogin\fR(8)\&. diff --git a/man/man5/porttime.5 b/man/man5/porttime.5 new file mode 100644 index 0000000..b9f9e3d --- /dev/null +++ b/man/man5/porttime.5 @@ -0,0 +1,96 @@ +'\" t +.\" Title: porttime +.\" Author: Julianne Frances Haugh +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "PORTTIME" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +porttime \- port access time file +.SH "DESCRIPTION" +.PP +\fIporttime\fR +contains a list of tty devices, user names, and permitted login times\&. +.PP +Each entry consists of three colon separated fields\&. The first field is a comma separated list of tty devices, or an asterisk to indicate that all tty devices are matched by this entry\&. The second field is a comma separated list of user names, or an asterisk to indicated that all user names are matched by this entry\&. The third field is a comma separated list of permitted access times\&. +.PP +Each access time entry consists of zero or more days of the week, abbreviated +\fISu\fR, +\fIMo\fR, +\fITu\fR, +\fIWe\fR, +\fITh\fR, +\fIFr\fR, and +\fISa\fR, followed by a pair of times separated by a hyphen\&. The abbreviation +\fIWk\fR +may be used to represent Monday thru Friday, and +\fIAl\fR +may be used to indicate every day\&. If no days are given, +\fIAl\fR +is assumed\&. +.SH "EXAMPLES" +.PP +The following entry allows access to user +\fBjfh\fR +on every port during weekdays from 9am to 5pm\&. +.PP +*:jfh:Wk0900\-1700 +.PP +The following entries allow access only to the users +\fIroot\fR +and +\fIoper\fR +on +/dev/console +at any time\&. This illustrates how the +/etc/porttime +file is an ordered list of access times\&. Any other user would match the second entry which does not permit access at any time\&. +.sp +.if n \{\ +.RS 4 +.\} +.nf + console:root,oper:Al0000\-2400 + console:*: + +.fi +.if n \{\ +.RE +.\} +.PP +The following entry allows access for the user +\fIgames\fR +on any port during non\-working hours\&. +.PP +*:games:Wk1700\-0900,SaSu0000\-2400 +.SH "FILES" +.PP +/etc/porttime +.RS 4 +File containing port access\&. +.RE +.SH "SEE ALSO" +.PP +\fBlogin\fR(1)\&. diff --git a/man/man5/shadow.5 b/man/man5/shadow.5 new file mode 100644 index 0000000..5ab04b8 --- /dev/null +++ b/man/man5/shadow.5 @@ -0,0 +1,148 @@ +'\" t +.\" Title: shadow +.\" Author: Julianne Frances Haugh +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "SHADOW" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +shadow \- shadowed password file +.SH "DESCRIPTION" +.PP +shadow +is a file which contains the password information for the system\*(Aqs accounts and optional aging information\&. +.PP +This file must not be readable by regular users if password security is to be maintained\&. +.PP +Each line of this file contains 9 fields, separated by colons (\(lq:\(rq), in the following order: +.PP +\fBlogin name\fR +.RS 4 +It must be a valid account name, which exist on the system\&. +.RE +.PP +\fBencrypted password\fR +.RS 4 +This field may be empty, in which case no passwords are required to authenticate as the specified login name\&. However, some applications which read the +/etc/shadow +file may decide not to permit any access at all if the password field is empty\&. +.sp +A password field which starts with an exclamation mark means that the password is locked\&. The remaining characters on the line represent the password field before the password was locked\&. +.sp +Refer to +\fBcrypt\fR(3) +for details on how this string is interpreted\&. +.sp +If the password field contains some string that is not a valid result of +\fBcrypt\fR(3), for instance ! or *, the user will not be able to use a unix password to log in (but the user may log in the system by other means)\&. +.RE +.PP +\fBdate of last password change\fR +.RS 4 +The date of the last password change, expressed as the number of days since Jan 1, 1970 00:00 UTC\&. +.sp +The value 0 has a special meaning, which is that the user should change her password the next time she will log in the system\&. +.sp +An empty field means that password aging features are disabled\&. +.RE +.PP +\fBminimum password age\fR +.RS 4 +The minimum password age is the number of days the user will have to wait before she will be allowed to change her password again\&. +.sp +An empty field and value 0 mean that there is no minimum password age\&. +.RE +.PP +\fBmaximum password age\fR +.RS 4 +The maximum password age is the number of days after which the user will have to change her password\&. +.sp +After this number of days is elapsed, the password may still be valid\&. The user should be asked to change her password the next time she will log in\&. +.sp +An empty field means that there are no maximum password age, no password warning period, and no password inactivity period (see below)\&. +.sp +If the maximum password age is lower than the minimum password age, the user cannot change her password\&. +.RE +.PP +\fBpassword warning period\fR +.RS 4 +The number of days before a password is going to expire (see the maximum password age above) during which the user should be warned\&. +.sp +An empty field and value 0 mean that there are no password warning period\&. +.RE +.PP +\fBpassword inactivity period\fR +.RS 4 +The number of days after a password has expired (see the maximum password age above) during which the password should still be accepted (and the user should update her password during the next login)\&. +.sp +After expiration of the password and this expiration period is elapsed, no login is possible for the user\&. The user should contact her administrator\&. +.sp +An empty field means that there are no enforcement of an inactivity period\&. +.RE +.PP +\fBaccount expiration date\fR +.RS 4 +The date of expiration of the account, expressed as the number of days since Jan 1, 1970 00:00 UTC\&. +.sp +Note that an account expiration differs from a password expiration\&. In case of an account expiration, the user shall not be allowed to login\&. In case of a password expiration, the user is not allowed to login using her password\&. +.sp +An empty field means that the account will never expire\&. +.sp +The value 0 should not be used as it is interpreted as either an account with no expiration, or as an expiration on Jan 1, 1970\&. +.RE +.PP +\fBreserved field\fR +.RS 4 +This field is reserved for future use\&. +.RE +.SH "FILES" +.PP +/etc/passwd +.RS 4 +User account information\&. +.RE +.PP +/etc/shadow +.RS 4 +Secure user account information\&. +.RE +.PP +/etc/shadow\- +.RS 4 +Backup file for /etc/shadow\&. +.sp +Note that this file is used by the tools of the shadow toolsuite, but not by all user and password management tools\&. +.RE +.SH "SEE ALSO" +.PP +\fBchage\fR(1), +\fBlogin\fR(1), +\fBpasswd\fR(1), +\fBpasswd\fR(5), +\fBpwck\fR(8), +\fBpwconv\fR(8), +\fBpwunconv\fR(8), +\fBsu\fR(1), +\fBsulogin\fR(8)\&. diff --git a/man/man5/suauth.5 b/man/man5/suauth.5 new file mode 100644 index 0000000..7c7729c --- /dev/null +++ b/man/man5/suauth.5 @@ -0,0 +1,146 @@ +'\" t +.\" Title: suauth +.\" Author: Marek Michałkiewicz +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "SUAUTH" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +suauth \- detailed su control file +.SH "SYNOPSIS" +.HP \w'\fB/etc/suauth\fR\ 'u +\fB/etc/suauth\fR +.SH "DESCRIPTION" +.PP +The file +/etc/suauth +is referenced whenever the su command is called\&. It can change the behaviour of the su command, based upon: +.sp +.if n \{\ +.RS 4 +.\} +.nf + 1) the user su is targeting + +.fi +.if n \{\ +.RE +.\} +.PP +2) the user executing the su command (or any groups he might be a member of) +.PP +The file is formatted like this, with lines starting with a # being treated as comment lines and ignored; +.sp +.if n \{\ +.RS 4 +.\} +.nf + to\-id:from\-id:ACTION + +.fi +.if n \{\ +.RE +.\} +.PP +Where to\-id is either the word +\fIALL\fR, a list of usernames delimited by "," or the words +\fIALL EXCEPT\fR +followed by a list of usernames delimited by ","\&. +.PP +from\-id is formatted the same as to\-id except the extra word +\fIGROUP\fR +is recognized\&. +\fIALL EXCEPT GROUP\fR +is perfectly valid too\&. Following +\fIGROUP\fR +appears one or more group names, delimited by ","\&. It is not sufficient to have primary group id of the relevant group, an entry in +\fB/etc/group\fR(5) +is necessary\&. +.PP +Action can be one only of the following currently supported options\&. +.PP +\fIDENY\fR +.RS 4 +The attempt to su is stopped before a password is even asked for\&. +.RE +.PP +\fINOPASS\fR +.RS 4 +The attempt to su is automatically successful; no password is asked for\&. +.RE +.PP +\fIOWNPASS\fR +.RS 4 +For the su command to be successful, the user must enter his or her own password\&. They are told this\&. +.RE +.PP +Note there are three separate fields delimited by a colon\&. No whitespace must surround this colon\&. Also note that the file is examined sequentially line by line, and the first applicable rule is used without examining the file further\&. This makes it possible for a system administrator to exercise as fine control as he or she wishes\&. +.SH "EXAMPLE" +.sp +.if n \{\ +.RS 4 +.\} +.nf + # sample /etc/suauth file + # + # A couple of privileged usernames may + # su to root with their own password\&. + # + root:chris,birddog:OWNPASS + # + # Anyone else may not su to root unless in + # group wheel\&. This is how BSD does things\&. + # + root:ALL EXCEPT GROUP wheel:DENY + # + # Perhaps terry and birddog are accounts + # owned by the same person\&. + # Access can be arranged between them + # with no password\&. + # + terry:birddog:NOPASS + birddog:terry:NOPASS + # + +.fi +.if n \{\ +.RE +.\} +.SH "FILES" +.PP +/etc/suauth +.RS 4 +.RE +.SH "BUGS" +.PP +There could be plenty lurking\&. The file parser is particularly unforgiving about syntax errors, expecting no spurious whitespace (apart from beginning and end of lines), and a specific token delimiting different things\&. +.SH "DIAGNOSTICS" +.PP +An error parsing the file is reported using +\fBsyslogd\fR(8) +as level ERR on facility AUTH\&. +.SH "SEE ALSO" +.PP +\fBsu\fR(1)\&. diff --git a/man/man5/subgid.5 b/man/man5/subgid.5 new file mode 100644 index 0000000..73b8617 --- /dev/null +++ b/man/man5/subgid.5 @@ -0,0 +1,120 @@ +'\" t +.\" Title: subgid +.\" Author: Eric Biederman +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "SUBGID" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +subgid \- the configuration for subordinate group ids +.SH "DESCRIPTION" +.PP +Subgid authorizes a group id to map ranges of group ids from its namespace into child namespaces\&. +.PP +The delegation of the subordinate gids can be configured via the +\fIsubid\fR +field in +/etc/nsswitch\&.conf +file\&. Only one value can be set as the delegation source\&. Setting this field to +\fIfiles\fR +configures the delegation of gids to +/etc/subgid\&. Setting any other value treats the delegation as a plugin following with a name of the form +\fIlibsubid_$value\&.so\fR\&. If the value or plugin is missing, then the subordinate gid delegation falls back to +\fIfiles\fR\&. +.PP +Note, that +\fBgroupadd\fR +will only create entries in +/etc/subgid +if subid delegation is managed via subid files\&. +.SH "LOCAL SUBORDINATE DELEGATION" +.PP +Each line in +/etc/subgid +contains a user name and a range of subordinate group ids that user is allowed to use\&. This is specified with three fields delimited by colons (\(lq:\(rq)\&. These fields are: +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +login name or UID +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +numerical subordinate group ID +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +numerical subordinate group ID count +.RE +.PP +This file specifies the group IDs that ordinary users can use, with the +\fBnewgidmap\fR +command, to configure gid mapping in a user namespace\&. +.PP +Multiple ranges may be specified per user\&. +.PP +When large number of entries (10000\-100000 or more) are defined in +/etc/subgid, parsing performance penalty will become noticeable\&. In this case it is recommended to use UIDs instead of login names\&. Benchmarks have shown speed\-ups up to 20x\&. +.SH "FILES" +.PP +/etc/subgid +.RS 4 +Per user subordinate group IDs\&. +.RE +.PP +/etc/subgid\- +.RS 4 +Backup file for /etc/subgid\&. +.RE +.SH "SEE ALSO" +.PP +\fBlogin.defs\fR(5), +\fBnewgidmap\fR(1), +\fBnewuidmap\fR(1), +\fBnewusers\fR(8), +\fBsubuid\fR(5), +\fBuseradd\fR(8), +\fBuserdel\fR(8), +\fBusermod\fR(8), +\fBuser_namespaces\fR(7)\&. diff --git a/man/man5/subuid.5 b/man/man5/subuid.5 new file mode 100644 index 0000000..655fbb9 --- /dev/null +++ b/man/man5/subuid.5 @@ -0,0 +1,120 @@ +'\" t +.\" Title: subuid +.\" Author: Eric Biederman +.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/> +.\" Date: 11/08/2022 +.\" Manual: File Formats and Configuration Files +.\" Source: shadow-utils 4.13 +.\" Language: English +.\" +.TH "SUBUID" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration" +.\" ----------------------------------------------------------------- +.\" * Define some portability stuff +.\" ----------------------------------------------------------------- +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.\" http://bugs.debian.org/507673 +.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html +.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.SH "NAME" +subuid \- the configuration for subordinate user ids +.SH "DESCRIPTION" +.PP +Subuid authorizes a user id to map ranges of user ids from its namespace into child namespaces\&. +.PP +The delegation of the subordinate uids can be configured via the +\fIsubid\fR +field in +/etc/nsswitch\&.conf +file\&. Only one value can be set as the delegation source\&. Setting this field to +\fIfiles\fR +configures the delegation of uids to +/etc/subuid\&. Setting any other value treats the delegation as a plugin following with a name of the form +\fIlibsubid_$value\&.so\fR\&. If the value or plugin is missing, then the subordinate uid delegation falls back to +\fIfiles\fR\&. +.PP +Note, that +\fBuseradd\fR +will only create entries in +/etc/subuid +if subid delegation is managed via subid files\&. +.SH "LOCAL SUBORDINATE DELEGATION" +.PP +Each line in +/etc/subuid +contains a user name and a range of subordinate user ids that user is allowed to use\&. This is specified with three fields delimited by colons (\(lq:\(rq)\&. These fields are: +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +login name or UID +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +numerical subordinate user ID +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +numerical subordinate user ID count +.RE +.PP +This file specifies the user IDs that ordinary users can use, with the +\fBnewuidmap\fR +command, to configure uid mapping in a user namespace\&. +.PP +Multiple ranges may be specified per user\&. +.PP +When large number of entries (10000\-100000 or more) are defined in +/etc/subuid, parsing performance penalty will become noticeable\&. In this case it is recommended to use UIDs instead of login names\&. Benchmarks have shown speed\-ups up to 20x\&. +.SH "FILES" +.PP +/etc/subuid +.RS 4 +Per user subordinate user IDs\&. +.RE +.PP +/etc/subuid\- +.RS 4 +Backup file for /etc/subuid\&. +.RE +.SH "SEE ALSO" +.PP +\fBlogin.defs\fR(5), +\fBnewgidmap\fR(1), +\fBnewuidmap\fR(1), +\fBnewusers\fR(1), +\fBsubgid\fR(5), +\fBuseradd\fR(8), +\fBuserdel\fR(8), +\fBusermod\fR(8), +\fBuser_namespaces\fR(7)\&. |