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CVTSUDOERS(1) FreeBSD General Commands Manual CVTSUDOERS(1)
NAME cvtsudoers - convert between sudoers file formats
SYNOPSIS cvtsudoers [-ehMpV] [-b dn] [-c conf_file] [-d deftypes] [-f output_format] [-i input_format] [-I increment] [-l log_file] [-m filter] [-o output_file] [-O start_point] [-P padding] [-s sections] [input_file ...]
DESCRIPTION The cvtsudoers utility accepts one or more security policies in either sudoers or LDIF format as input, and generates a single policy of the specified format as output. The default input format is sudoers. The default output format is LDIF. It is only possible to convert a policy file that is syntactically correct.
If no input_file is specified, or if it is `-', the policy is read from the standard input. Input files may be optionally prefixed with a host name followed by a colon (`:') to make the policy rules specific to a host when merging multiple files. By default, the result is written to the standard output.
The options are as follows:
-b dn, --base=dn The base DN (distinguished name) that will be used when performing LDAP queries. Typically this is of the form "ou=SUDOers,dc=my-domain,dc=com" for the domain my-domain.com. If this option is not specified, the value of the SUDOERS_BASE environment variable will be used instead. Only necessary when converting to LDIF format.
-c conf_file, --config=conf_file Specify the path to the configuration file. Defaults to /usr/local/etc/cvtsudoers.conf.
-d deftypes, --defaults=deftypes Only convert Defaults entries of the specified types. One or more Defaults types may be specified, separated by a comma (`,'). The supported types are:
all All Defaults entries.
global Global Defaults entries that are applied regardless of user, runas, host, or command.
user Per-user Defaults entries.
runas Per-runas user Defaults entries.
host Per-host Defaults entries.
command Per-command Defaults entries.
See the Defaults section in sudoers(5) for more information.
If the -d option is not specified, all Defaults entries will be Specify the output format (case-insensitive). The following formats are supported:
CSV CSV (comma-separated value) files are often used by spreadsheets and report generators. See CSV output format for more details.
JSON JSON (JavaScript Object Notation) files are usually easier for third-party applications to consume than the traditional sudoers format. The various values have explicit types which removes much of the ambiguity of the sudoers format. See JSON output format for more details.
LDIF LDIF (LDAP Data Interchange Format) files can be imported into an LDAP server for use with sudoers.ldap(5).
Conversion to LDIF has the following limitations:
o Command, host, runas, and user-specific Defaults lines cannot be translated as they don't have an equivalent in the sudoers LDAP schema.
o Command, host, runas, and user aliases are not supported by the sudoers LDAP schema so they are expanded during the conversion.
sudoers Traditional sudoers format. A new sudoers file will be reconstructed from the parsed input file. Comments are not preserved and data from any include files will be output inline.
--group-file=file When the -M option is also specified, perform group queries using file instead of the system group database.
-h, --help Display a short help message to the standard output and exit.
-i input_format, --input-format=input_format Specify the input format. The following formats are supported:
LDIF LDIF (LDAP Data Interchange Format) files can be exported from an LDAP server to convert security policies used by sudoers.ldap(5). If a base DN (distinguished name) is specified, only sudoRole objects that match the base DN will be processed. Not all sudoOptions specified in a sudoRole can be translated from LDIF to sudoers format.
sudoers Traditional sudoers format. This is the default input format.
-I increment, --increment=increment When generating LDIF output, increment each sudoOrder attribute by the specified number. Defaults to an increment of 1.
-l log_file, --logfile=log_file by a comma (`,'). The key may be "cmnd" (or "cmd"), "host", "group", or "user". For example, user = operator or host = www. An upper-case Cmnd_Alias, Host_alias, or User_Alias may be specified as the "cmnd", "host", or "user".
A matching sudoers rule may also include users, groups, and hosts that are not part of the filter. This can happen when a rule includes multiple users, groups, or hosts. To prune out any non- matching user, group, or host from the rules, the -p option may be used.
By default, the password and group databases are not consulted when matching against the filter so the users and groups do not need to be present on the local system (see the -M option). Only aliases that are referenced by the filtered policy rules will be displayed.
-M, --match-local When the -m option is also specified, use password and group database information when matching users and groups in the filter. Only users and groups in the filter that exist on the local system will match, and a user's groups will automatically be added to the filter. If the -M is not specified, users and groups in the filter do not need to exist on the local system, but all groups used for matching must be explicitly listed in the filter.
-o output_file, --output=output_file Write the converted output to output_file. If no output_file is specified, or if it is `-', the converted sudoers policy will be written to the standard output.
-O start_point, --order-start=start_point When generating LDIF output, use the number specified by start_point in the sudoOrder attribute of the first sudoRole object. Subsequent sudoRole object use a sudoOrder value generated by adding an increment, see the -I option for details. Defaults to a starting point of 1. A starting point of 0 will disable the generation of sudoOrder attributes in the resulting LDIF file.
--passwd-file=file When the -M option is also specified, perform passwd queries using file instead of the system passwd database.
-p, --prune-matches When the -m option is also specified, cvtsudoers will prune out non-matching users, groups, and hosts from matching entries.
-P padding, --padding=padding When generating LDIF output, construct the initial sudoOrder value by concatenating order_start and increment, padding the increment with zeros until it consists of padding digits. For example, if order_start is 1027, padding is 3, and increment is 1, the value of sudoOrder for the first entry will be 1027000, followed by 1027001, 1027002, etc. If the number of sudoRole entries is larger than the padding would allow, cvtsudoers will exit with an error. By default, no padding is performed.
Print the cvtsudoers and sudoers grammar versions and exit.
Merging multiple files When multiple input files are specified, cvtsudoers will attempt to merge them into a single policy file. It is assumed that user and group names are consistent among the policy files to be merged. For example, user "bob" on one host is the same as user "bob" on another host.
When merging policy files, it is possible to prefix the input file name with a host name, separated by a colon (`:'). When the files are merged, the host name will be used to restrict the policy rules to that specific host where possible.
The merging process is performed as follows:
o Each input file is parsed into internal sudoers data structures.
o Aliases are merged and renamed as necessary to avoid conflicts. In the event of a conflict, the first alias found is left as-is and subsequent aliases of the same name are renamed with a numeric suffix separated with a underscore (`_'). For example, if there are two different aliases named SERVERS, the first will be left as-is and the second will be renamed SERVERS_1. References to the renamed alias are also updated in the policy file. Duplicate aliases (those with identical contents) are pruned.
o Defaults settings are merged and duplicates are removed. If there are conflicts in the Defaults settings, a warning is emitted for each conflict. If a host name is specified with the input file, cvtsudoers will change the global Defaults settings in that file to be host- specific. A warning is emitted for command, user, or runas-specific Defaults settings which cannot be made host-specific.
o Per-user rules are merged and duplicates are removed. If a host name is specified with the input file, cvtsudoers will change rules that specify a host name of ALL to the host name associated with the policy file being merged. The merging of rules is currently fairly simplistic but will be improved in a later release.
It is possible to merge policy files with differing formats.
The cvtsudoers.conf file Options in the form "keyword = value" may also be specified in a configuration file, /usr/local/etc/cvtsudoers.conf by default. The following keywords are recognized:
defaults = deftypes See the description of the -d command line option.
expand_aliases = yes | no See the description of the -e command line option.
group_file = file See the description of the --group-file command line option.
input_format = ldif | sudoers See the description of the -i command line option.
match = filter
order_start = start_point See the description of the -O command line option.
output_format = csv | json | ldif | sudoers See the description of the -f command line option.
padding = padding See the description of the -P command line option.
passwd_file = file See the description of the --passwd-file command line option.
prune_matches = yes | no See the description of the -p command line option.
sudoers_base = dn See the description of the -b command line option.
suppress = sections See the description of the -s command line option.
Options on the command line will override values from the configuration file.
JSON output format The sudoers JSON format may contain any of the following top-level objects:
Defaults An array of objects, each containing an Options array and an optional Binding array.
The Options array consists of one or more objects, each containing a "name:value" pair that corresponds to a sudoers Defaults setting. Options that operate on a list will also include an operation entry in the object, with a value of "list_assign" for `=', "list_add" for `+=', or "list_remove" for `-='.
The optional Binding array consists of one or more objects, each containing a "name:value" pair and an optional negated entry, which will negate any comparison performed with the object. If a Binding is present, the setting will only take effect if one of the specified command, hostname, netgroup, networkaddr, nonunixgid, nonunixgroup, usergid, usergroup, userid, username, or alias entries match.
For example, the following sudoers entry:
Defaults@somehost set_home, env_keep += DISPLAY
converts to:
"Defaults": [ { "Binding": [ { "hostname": "somehost" } ], "Options": [ ] } ]
User_Aliases A JSON object containing one or more sudoers User_Alias entries where each named alias has as its value an array containing one or more objects. Each object contains a "name:value" pair and an optional negated entry, which will negate any comparison performed with the object. The name may be one of netgroup, nonunixgid, nonunixgroup, useralias, usergid, usergroup, userid, or username.
For example, the following sudoers entry:
User_Alias SYSADMIN = will, %wheel, +admin
converts to:
"User_Aliases": { "SYSADMIN": [ { "username": "will" }, { "usergroup": "wheel" }, { "netgroup": "admin" } ] }
Runas_Aliases A JSON object containing one or more sudoers Runas_Alias entries, where each named alias has as its value an array containing one or more objects. Each object contains a "name:value" pair and an optional negated entry, which will negate any comparison performed with the object. The name may be one of netgroup, nonunixgid, nonunixgroup, runasalias, usergid, usergroup, userid, or username.
For example, the following sudoers entry:
Runas_Alias DB = oracle, sybase : OP = root, operator
converts to:
"Runas_Aliases": { "DB": [ { "username": "oracle" }, { "username": "sybase" } ], "OP": [ { "username": "root" }, { "username": "operator" } ] }
Host_Aliases A JSON object containing one or more sudoers Host_Alias entries where each named alias has as its value an array containing one or more objects. Each object contains a "name:value" pair and an optional negated entry, which will negate any comparison performed with the object. The name may be one of hostalias, hostname, netgroup, or networkaddr.
"Host_Aliases": { "DORMNET": [ { "networkaddr": "128.138.243.0" }, { "networkaddr": "128.138.204.0/24" } ], "SERVERS": [ { "hostname": "boulder" }, { "hostname": "refuge" } ] }
Cmnd_Aliases A JSON object containing one or more sudoers Cmnd_Alias entries where each named alias has as its value an array containing one or more objects. Each object contains a "name:value" pair and an optional negated entry, which will negate any comparison performed with the object. The name may be either another cmndalias or a command. For example, the following sudoers entries:
Cmnd_Alias SHELLS = /bin/bash, /bin/csh, /bin/sh, /bin/zsh Cmnd_Alias VIPW = /usr/bin/chpass, /usr/bin/chfn, /usr/bin/chsh, \ /usr/bin/passwd, /usr/sbin/vigr, /usr/sbin/vipw
convert to:
"Cmnd_Aliases": { "SHELLS": [ { "command": "/bin/bash" }, { "command": "/bin/csh" }, { "command": "/bin/sh" }, { "command": "/bin/zsh" } ], "VIPW": [ { "command": "/usr/bin/chpass" }, { "command": "/usr/bin/chfn" }, { "command": "/usr/bin/chsh" }, { "command": "/usr/bin/passwd" }, { "command": "/usr/sbin/vigr" }, { "command": "/usr/sbin/vipw" } ] }
User_Specs A JSON array containing one or more objects, each representing a sudoers User_Spec. Each object in the User_Specs array should contain a User_List array, a Host_List array and a Cmnd_Specs array.
A User_List consists of one or more objects. Each object contains a "name:value" pair and an optional negated entry, which will negate any comparison performed with the object. The name may be one of netgroup, nonunixgid, nonunixgroup, useralias, usergid, usergroup, userid, or username. If username is set to the special value ALL, it will match any user.
A Host_List consists of one or more objects. Each object contains a "name:value" pair and an optional negated entry, which will negate any comparison performed with the object. The name may be one of hostalias, hostname, netgroup, or networkaddr. If hostname The Commands array consists of one or more objects containing "name:value" pair elements. The following names and values are supported:
command A string containing the command to run. The special value ALL it will match any command.
negated A boolean value that, if true, will negate any comparison performed with the object.
sha224 A string containing the SHA224 digest of the command.
sha256 A string containing the SHA256 digest of the command.
sha384 A string containing the SHA384 digest of the command.
sha512 A string containing the SHA512 digest of the command.
The runasusers array consists of objects describing users the command may be run as. Each object contains a "name:value" pair and an optional negated entry, which will negate any comparison performed with the object. The name may be one of netgroup, nonunixgid, nonunixgroup, runasalias, usergid, usergroup, userid, or username. If username is set to the special value ALL, it will match any user. If username is set to the empty string "", it will match the invoking user.
The runasgroups array consists of objects describing groups the command may be run as. Each object contains a "name:value" pair and an optional negated entry, which will negate any comparison performed with the object. The name may be one of runasalias, usergid, or usergroup. If usergroup is set to the special value ALL, it will match any group.
The Options array is of the same format as the one in the Defaults object. Any Tag_Spec entries in sudoers are converted to Options. A user with "sudo ALL" privileges will automatically have the setenv option enabled to match the implicit behavior provided by sudoers.
For example, the following sudoers entry:
millert ALL = (ALL : ALL) NOPASSWD: ALL, !/usr/bin/id
converts to:
"User_Specs": [ { "User_List": [ { "username": "millert" } ], "Host_List": [ { "hostname": "ALL" } ], "Cmnd_Specs": [ { "runasusers": [ { "username": "ALL" } ], "Commands": [ { "command": "ALL" }, { "command": "/usr/bin/id", "negated": true } ] } ] } ]
CSV output format CSV (comma-separated value) files are often used by spreadsheets and report generators. For CSV output, cvtsudoers double quotes strings that contain commas. For each literal double quote character present inside the string, two double quotes are output. This method of quoting commas is compatible with most spreadsheet programs.
There are three possible sections in cvtsudoers's CSV output, each separated by a blank line:
defaults This section includes any Defaults settings in sudoers. The defaults section begins with the following heading:
defaults_type,binding,name,operator,value
The fields are as follows:
defaults_type The type of Defaults setting; one of defaults, defaults_command, defaults_host, defaults_runas, or defaults_user.
binding For defaults_command, defaults_host, defaults_runas, and defaults_user this is the value that must match for the setting to be applied.
name The name of the Defaults setting.
operator The operator determines how the value is applied to the setting. It may be either `=' (assignment), `+=' (append), or `-=' (remove).
value The setting's value, usually a string or, for settings used in a boolean context, true or false.
aliases This section includes any Cmnd_Alias Host_Alias, Runas_Alias, or User_Alias, entries from sudoers. The aliases section begins with the following heading:
alias_type,alias_name,members
The fields are as follows: letter that consists of upper-case letters, digits, or underscores.
members A comma-separated list of members belonging to the alias. Due to the use of commas, members is surrounded by double quotes if it contains more than one member.
rules This section includes the sudoers rules that grant privileges. The rules section begins with the following heading:
rule,user,host,runusers,rungroups,options,command
The fields are as follows:
rule This field indicates a sudoers rule entry.
user The user the rule applies to. This may also be a Unix group (preceded by a `%' character), a non-Unix group (preceded by `%:') or a netgroup (preceded by a `+' character) or a User_Alias. If set to the special value ALL, it will match any user.
host The host the rule applies to. This may also be a netgroup (preceded by a `+' character) or a Host_Alias. If set to the special value ALL, it will match any host.
runusers An optional comma-separated list of users (or Runas_Aliases) the command may be run as. If it contains more than one member, the value is surrounded by double quotes. If set to the special value ALL, it will match any user. If empty, the root user is assumed.
rungroups An optional comma-separated list of groups (or Runas_Aliases) the command may be run as. If it contains more than one member, the value is surrounded by double quotes. If set to the special value ALL, it will match any group. If empty, the runuser's group is used.
options An optional list of Defaults settings to apply to the command. Any Tag_Spec entries in sudoers are converted to options.
commands A list of commands, with optional arguments, that the user is allowed to run. If set to the special value ALL, it will match any command.
For example, the following sudoers entry:
millert ALL = (ALL : ALL) NOPASSWD: ALL, !/usr/bin/id
converts to:
rule,millert,ALL,ALL,ALL,"!authenticate","ALL,!/usr/bin/id"
ldap.conf file uses a sudoers_base of my-domain,dc=com, storing the result in sudoers.ldif:
$ cvtsudoers -b ou=SUDOers,dc=my-domain,dc=com -o sudoers.ldif \ /etc/sudoers
Convert /etc/sudoers to JSON format, storing the result in sudoers.json:
$ cvtsudoers -f json -o sudoers.json /etc/sudoers
Parse /etc/sudoers and display only rules that match user ambrose on host hastur:
$ cvtsudoers -f sudoers -m user=ambrose,host=hastur /etc/sudoers
Same as above, but expand aliases and prune out any non-matching users and hosts from the expanded entries.
$ cvtsudoers -ep -f sudoers -m user=ambrose,host=hastur /etc/sudoers
Convert sudoers.ldif from LDIF to traditional sudoers format:
$ cvtsudoers -i ldif -f sudoers -o sudoers.new sudoers.ldif
Merge a global sudoers file with two host-specific policy files from the hosts "xyzzy" and "plugh":
$ cvtsudoers -f sudoers -o sudoers.merged sudoers \ xyzzy:sudoers.xyzzy plugh:sudoers.plugh
SEE ALSO sudoers(5), sudoers.ldap(5), sudo(8)
AUTHORS Many people have worked on sudo over the years; this version consists of code written primarily by:
Todd C. Miller
See the CONTRIBUTORS.md file in the sudo distribution (https://www.sudo.ws/about/contributors/) for an exhaustive list of people who have contributed to sudo.
BUGS If you believe you have found a bug in cvtsudoers, you can submit a bug report at https://bugzilla.sudo.ws/
SUPPORT Limited free support is available via the sudo-users mailing list, see https://www.sudo.ws/mailman/listinfo/sudo-users to subscribe or search the archives.
DISCLAIMER cvtsudoers is provided "AS IS" and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. See the LICENSE.md file distributed with sudo or https://www.sudo.ws/about/license/ for complete details.