SMBCACLS(1)

📦
version 4.24.7 · 27 versions
, in fedora 44

💖 SMBCACLS 💖

ok so this is the SMBCACLS(1) page, it lives in the User Commands section of the manual, and bestie… it's a whole journey. buckle up. 🎀

✨ NAME ✨

smbcacls — Set or get ACLs on an NT file or directory names

🌸 SYNOPSIS 🌸

smbcacls {//server/share} {/filename} [-D|--delete=ACL]
 [-M|--modify=ACL] [-a|--add=ACL] [-S|--set=ACLS] [-C|--chown=USERNAME]
 [-G|--chgrp=GROUPNAME] [-I|--inherit=STRING] [--recurse]
 [--propagate-inheritance] [--save=savefile] [--restore=restorefile]
 [--numeric] [--sddl] [--query-security-info=INT]
 [--set-security-info=INT] [-t|--test-args] [--domain-sid=SID]
 [-x|--maximum-access] [-?|--help] [--usage]
 [-d|--debuglevel=DEBUGLEVEL] [--debug-stdout] [--configfile=CONFIGFILE]
 [--option=name=value] [-l|--log-basename=LOGFILEBASE] [--leak-report]
 [--leak-report-full] [-R|--name-resolve=NAME-RESOLVE-ORDER]
 [-O|--socket-options=SOCKETOPTIONS] [-m|--max-protocol=MAXPROTOCOL]
 [-n|--netbiosname=NETBIOSNAME] [--netbios-scope=SCOPE]
 [-W|--workgroup=WORKGROUP] [--realm=REALM]
 [-U|--user=[DOMAIN/]USERNAME[%PASSWORD]] [-N|--no-pass]
 [--password=STRING] [--pw-nt-hash] [-A|--authentication-file=FILE]
 [-P|--machine-pass] [--simple-bind-dn=DN]
 [--use-kerberos=desired|required|off] [--use-krb5-ccache=CCACHE]
 [--use-winbind-ccache] [--client-protection=sign|encrypt|off]
 [-V|--version]

🦋 DESCRIPTION 🦋

This tool is part of the samba(7) suite. iykyk. 💅

The smbcacls program manipulates NT Access Control Lists (ACLs) on SMB file shares. An ACL comprises zero or more Access Control Entries (ACEs), which define access restrictions for a specific user or group.

lowkey the whole vibe of this tool is: who gets to touch what, and how do we say that in NT-flavored legalese. no cap.

🔥 OPTIONS 🔥

The following options are available to the smbcacls program. The format of ACLs is described in the section ACL FORMAT (coming at you later in this page, bestie, keep reading).

  • -a|--add acl — Add the entries specified to the ACL. Existing access control entries are unchanged. (we're adding, not replacing, she's polite like that 🫶)
  • -M|--modify acl — Modify the mask value (permissions) for the ACEs specified on the command line. An error will be printed for each ACE specified that was not already present in the object's ACL. 😭 so if you try to modify something that isn't there, she WILL tell you.
  • -D|--delete acl — Delete any ACEs specified on the command line. An error will be printed for each ACE specified that was not already present in the object's ACL. (same energy: not-there means error message, periodt.)
  • -S|--set acl — This command sets the ACL on the object with only what is specified on the command line. Any existing ACL is erased. ⚠️ Note that the ACL specified must contain at least a revision, type, owner and group for the call to succeed.
bestie this one is the scorched earth option. everything you didn't list? gone. bye. ✨
  • -C|--chown name — The owner of a file or directory can be changed to the name given using the -C option. The name can be a sid in the form S-1-x-y-z or a name resolved against the server specified in the first argument.

This command is a shortcut for -M OWNER:name.

  • -G|--chgrp name — The group owner of a file or directory can be changed to the name given using the -G option. The name can be a sid in the form S-1-x-y-z or a name resolved against the server specified n the first argument. (yes that typo is in the original, we respect the original 💀)

This command is a shortcut for -M GROUP:name.

  • -I|--inherit allow|remove|copy — Set or unset the windows "Allow inheritable permissions" check box using the -I option. To set the check box pass allow. To unset the check box pass either remove or copy. Remove will remove all inherited ACEs. Copy will copy all the inherited ACEs.
  • --propagate-inheritance — Add, modify, delete or set ACEs on an entire directory tree according to the inheritance flags. Refer to the INHERITANCE section for details.
  • --save savefile — stores the DACLs in sddl format of the specified file or folder for later use with restore. SACLs, owner or integrity labels are not stored. (she's picky about what she saves, and that's her right 💅)
  • --restore savefile — applies the stored DACLS to files in directory.
  • --recurse — indicates the operation is performed on directory and all files/directories below. (only applies to save option)
  • --numeric — This option displays all ACL information in numeric format. The default is to convert SIDs to names and ACE types and masks to a readable string format. (so default = pretty names, --numeric = raw digits. main character vs. lore dump.)
  • -m|--max-protocol PROTOCOL_NAME — This allows the user to select the highest SMB protocol level that smbcacls will use to connect to the server. By default this is set to NT1, which is the highest available SMB1 protocol. To connect using SMB2 or SMB3 protocol, use the strings SMB2 or SMB3 respectively. Note that to connect to a Windows 2012 server with encrypted transport selecting a max-protocol of SMB3 is required. 🔐
  • -t|--test-args — Don't actually do anything, only validate the correctness of the arguments. (dry run, bestie. she's just checking your fit before you leave the house. 🎀)
  • --query-security-info FLAGS — The security-info flags for queries.
  • --set-security-info FLAGS — The security-info flags for queries.
  • --sddl — Output and input acls in sddl format.
  • --domain-sid SID — SID used for sddl processing.
  • -x|--maximum-access — When displaying an ACL additionally query the server for effective maximum permissions. Note that this is only supported with SMB protocol version 2 or higher. (SMB1 girlies stay home for this one 🫠)
  • -?|--help — Print a summary of command line options.
  • --usage — Display brief usage message.
  • -d|--debuglevel= level — level is an integer from 0 to 10. The default value if this parameter is not specified is 1 for client applications.

The higher this value, the more detail will be logged to the log files about the activities of the server. At level 0, only critical errors and serious warnings will be logged. Level 1 is a reasonable level for day-to-day running — it generates a small amount of information about operations carried out.

Levels above 1 will generate considerable amounts of log data, and should only be used when investigating a problem. Levels above 3 are designed for use only by developers and generate HUGE amounts of log data, most of which is extremely cryptic. 😭

Note that specifying this parameter here will override the log level parameter in the /etc/samba/smb.conf file.

  • --debug-stdout — This will redirect debug output to STDOUT. By default all clients are logging to STDERR.
  • --configfile= <configuration file> — The file specified contains the configuration details required by the client. The information in this file can be general for client and server or only provide client specific like options such as client smb encrypt. See /etc/samba/smb.conf for more information. The default configuration file name is determined at compile time.
  • --option= <name>=<value> — Set the smb.conf(5) option "<name>" to value "<value>" from the command line. This overrides compiled-in defaults and options read from the configuration file. If a name or a value includes a space, wrap whole --option=name=value into quotes.
  • -l|--log-basename= logdirectory — Base directory name for log/debug files. The extension ".progname" will be appended (e.g. log.smbclient, log.smbd, etc...). The log file is never removed by the client.
  • --leak-report — Enable talloc leak reporting on exit.
  • --leak-report-full — Enable full talloc leak reporting on exit.
  • -V|--version — Prints the program version number.
  • -R|--name-resolve= NAME-RESOLVE-ORDER — This option is used to determine what naming services and in what order to resolve host names to IP addresses. The option takes a space-separated string of different name resolution options. The best is to wrap the whole --name-resolve=NAME-RESOLVE-ORDER into quotes.

The options are: "lmhosts", "host", "wins" and "bcast". They cause names to be resolved as follows:

  • lmhosts: Lookup an IP address in the Samba lmhosts file. If the line in lmhosts has no name type attached to the NetBIOS name (see the lmhosts(5) for details) then any name type matches for lookup.
  • host: Do a standard host name to IP address resolution, using the system /etc/hosts, NIS, or DNS lookups. This method of name resolution is operating system dependent, for instance on IRIX or Solaris this may be controlled by the /etc/nsswitch.conf file). Note that this method is only used if the NetBIOS name type being queried is the 0x20 (server) name type, otherwise it is ignored.
  • wins: Query a name with the IP address listed in the wins server parameter. If no WINS server has been specified this method will be ignored.
  • bcast: Do a broadcast on each of the known local interfaces listed in the interfaces parameter. This is the least reliable of the name resolution methods as it depends on the target host being on a locally connected subnet.

If this parameter is not set then the name resolve order defined in the /etc/samba/smb.conf file parameter (name resolve order) will be used.

The default order is lmhosts, host, wins, bcast. Without this parameter or any entry in the name resolve order parameter of the /etc/samba/smb.conf file, the name resolution methods will be attempted in this order.

  • -O|--socket-options= SOCKETOPTIONS — TCP socket options to set on the client socket. See the socket options parameter in the /etc/samba/smb.conf manual page for the list of valid options.
  • -m|--max-protocol= MAXPROTOCOL — The value of the parameter (a string) is the highest protocol level that will be supported by the client.

Note that specifying this parameter here will override the client max protocol parameter in the /etc/samba/smb.conf file.

  • -n|--netbiosname= NETBIOSNAME — This option allows you to override the NetBIOS name that Samba uses for itself. This is identical to setting the netbios name parameter in the /etc/samba/smb.conf file. However, a command line setting will take precedence over settings in /etc/samba/smb.conf.
  • --netbios-scope= SCOPE — This specifies a NetBIOS scope that nmblookup will use to communicate with when generating NetBIOS names. For details on the use of NetBIOS scopes, see rfc1001.txt and rfc1002.txt. NetBIOS scopes are very rarely used, only set this parameter if you are the system administrator in charge of all the NetBIOS systems you communicate with.

(ok bestie we're not done yet — more of this page is coming, don't go anywhere 🦋)

  • -W, --workgroup=WORKGROUP — bestie, this sets the SMB domain of the username ✨. It overrides the default domain, which is the domain defined in smb.conf. Fun lil fact: if the domain you specify is the same as the server's NetBIOS name, it makes the client log on using the server's local SAM (as opposed to the Domain SAM) 💅.
Heads up: specifying this parameter here will override the workgroup parameter in the /etc/samba/smb.conf file. Like, completely. 🙈
  • -r, --realm=REALM — sets the realm for the domain 🎀.
And yeah, specifying this parameter here will override the realm parameter in the /etc/samba/smb.conf file. same energy as above, no cap.
  • -U, --user=[DOMAIN\]USERNAME[%PASSWORD] — sets the SMB username, or the username and password, whichever you're feeling 🌸.

If %PASSWORD isn't specified, the user gets prompted. Here's the lil scavenger hunt the client goes on: first it checks the USER environment variable (which is also permitted to contain the password, separated by a %), then the LOGNAME variable (which is not permitted to contain a password), and if either one exists, that value is used. If those environment variables are nowhere to be found, the username found in a Kerberos Credentials cache may be used 👑.

A third option is a credentials file containing the plaintext of the username and password. This is mainly for scripts, where the admin does not wish to pass the credentials on the command line or via environment variables. If you go this route, make certain that the permissions on the file restrict access from unwanted users. See the -A for more details 🔥.

⚠️ Be cautious about including passwords in scripts or passing user-supplied values onto the command line. For security it is better to let the Samba client tool ask for the password if needed, or obtain the password once with kinit.

While Samba will attempt to scrub the password from the process title (as seen in ps), this is after startup and so is subject to a race. so like, there's a tiny window. 😭

  • -N, --no-pass — if specified, this parameter suppresses the normal password prompt from the client to the user 🙅‍♀️. Super useful when you're accessing a service that does not require a password.

Unless a password is specified on the command line or this parameter is specified, the client will request a password.

And if a password is specified on the command line and this option is also defined, the password on the command line will be silently ignored and no password will be used 💀. silently. ignored. not a word.

  • --password — specify the password on the commandline.
⚠️ Be cautious about including passwords in scripts or passing user-supplied values onto the command line. For security it is better to let the Samba client tool ask for the password if needed, or obtain the password once with kinit.

If --password is not specified, the tool will check the PASSWD environment variable, followed by PASSWD_FD which is expected to contain an open file descriptor (FD) number 🔍.

Finally it will check PASSWD_FILE (containing a file path to be opened). The file should only contain the password. Make certain that the permissions on the file restrict access from unwanted users! 🫶

While Samba will attempt to scrub the password from the process title (as seen in ps), this is after startup and so is subject to a race.

  • --pw-nt-hash — the supplied password is the NT hash 🔐.
  • -A, --authentication-file=filename — this option lets you specify a file to read the username and password used in the connection from 📄. The format of the file is:
username = <value>
password = <value>
domain   = <value>

Make certain that the permissions on the file restrict access from unwanted users! 🚨

  • -P, --machine-pass — use stored machine account password 🤖.
  • --simple-bind-dn=DN — DN to use for a simple bind.
  • --use-kerberos=desired|required|off — this parameter determines whether Samba client tools will try to authenticate using Kerberos 🌈. For Kerberos authentication you should use DNS names instead of IP addresses when connecting to a service. By default Samba client tools will try to use the default Kerberos credential cache (ccache). In case the ccache does not exist or the -U|--user option was specified, clients will ask to enter a password and will obtain a Kerberos ticket (kinit) for you 🎟️. If you want to use an alternative Kerberos credentical cache, use the --use-krb5-ccache option.
Note that specifying this parameter here will override the client use kerberos parameter in the /etc/samba/smb.conf file.
  • --use-krb5-ccache=CCACHE — specifies the credential cache location for Kerberos authentication ✨.

This will enforce --use-kerberos=required. like, it's not asking. periodt.

  • --use-winbind-ccache — try to use the credential cache by winbind.
  • --client-protection=sign|encrypt|off — sets the connection protection the client tool should use 🛡️.
Note that specifying this parameter here will override the client protection parameter in the /etc/samba/smb.conf file.

In case you need more fine grained control you can use: --option=clientsmbencrypt=OPTION, --option=clientipcsigning=OPTION, --option=clientsigning=OPTION 💅.

🦋 ACL FORMAT 🦋

okay so here's the tea on the ACL format, bestie. The format of an ACL is one or more entries separated by either commas or newlines 📝. An ACL entry is one of the following:

REVISION:<revision number>
OWNER:<sid or name>
GROUP:<sid or name>
ACL:<sid or name>:<type>/<flags>/<mask>
  • OD — "Owner Defaulted" — Indicates that the SID of the owner of the security descriptor was provided by a default mechanism.
  • GD — "Group Defaulted" — Indicates that the SID of the security descriptor group was provided by a default mechanism.
  • DP — "DACL Present" — Indicates a security descriptor that has a discretionary access control list (DACL).
  • DD — "DACL Defaulted" — Indicates a security descriptor with a default DACL.
  • SP — "SACL Present" — Indicates a security descriptor that has a system access control list (SACL).
  • SD — "SACL Defaulted" — A default mechanism, rather than the original provider of the security descriptor, provided the SACL.
  • DT — "DACL Trusted"
  • SS — "Server Security"
  • DR — "DACL Inheritance Required" — Indicates a required security descriptor in which the DACL is set up to support automatic propagation of inheritable access control entries (ACEs) to existing child objects.
  • SR — "SACL Inheritance Required" — Indicates a required security descriptor in which the SACL is set up to support automatic propagation of inheritable ACEs to existing child objects.
  • DI — "DACL Auto Inherited" — Indicates a security descriptor in which the DACL is set up to support automatic propagation of inheritable access control entries (ACEs) to existing child objects.
  • SI — "SACL Auto Inherited" — Indicates a security descriptor in which the SACL is set up to support automatic propagation of inheritable ACEs to existing child objects.
  • PD — "DACL Protected" — Prevents the DACL of the security descriptor from being modified by inheritable ACEs.
  • PS — "SACL Protected" — Prevents the SACL of the security descriptor from being modified by inheritable ACEs.
  • RM — "RM Control Valid" — Indicates that the resource manager control is valid.
  • SR — "Self Relative" — Indicates a self-relative security descriptor.
not me noticing there are two SR entries in here 💀 i'm just the messenger, i'm copying exactly what the page says, both of them, bestie.

The revision of the ACL specifies the internal Windows NT ACL revision for the security descriptor. If not specified it defaults to 1. Using values other than 1 may cause strange behaviour 🙈 — so like, don't be cute with it.

The owner and group specify the owner and group sids for the object. If a SID in the format S-1-x-y-z is specified this is used, otherwise the name specified is resolved using the server on which the file or directory resides 🖥️.

ACEs are specified with an "ACL:" prefix, and define permissions granted to an SID. The SID again can be specified in S-1-x-y-z format or as a name, in which case it is resolved against the server on which the file or directory resides 🌸. The type, flags and mask values determine the type of access granted to the SID.

The type can be either ALLOWED or DENIED to allow/deny access to the SID ✅❌.

The flags field defines how the ACE should be considered when performing inheritance. smbcacls uses these flags when run with --propagate-inheritance.

Flags can be specified as decimal or hexadecimal values, or with the respective (XX) aliases, separated by a vertical bar "|" 🎀.

  • (OI) Object Inherit 0x1
  • (CI) Container Inherit 0x2
  • (NP) No Propagate Inherit 0x4
  • (IO) Inherit Only 0x8
  • (I) ACE was inherited 0x10

The mask is a value which expresses the access right granted to the SID 👑. It can be given as a decimal or hexadecimal value, or by using one of the following text strings which map to the NT file permissions of the same name.

  • R — Allow read access
  • W — Allow write access
  • X — Execute permission on the object
  • D — Delete the object
  • P — Change permissions
  • O — Take ownership

The following combined permissions can be specified:

  • READ — Equivalent to 'RX' permissions
  • CHANGE — Equivalent to 'RXWD' permissions
  • FULL — Equivalent to 'RWXDPO' permissions

and that's the whole ACL alphabet, bestie. it's giving ✨permission architecture✨ fr fr.

🦋 INHERITANCE 🦋

Okay bestie, this is the part where ACLs get ✨generational✨. Per-ACE inheritance flags can be set in the ACE flags field. By default, inheritable ACEs — like the ones marked for object inheritance (OI) or container inheritance (CI) — are not propagated to sub-files or folders. They just sit there, being mysterious. 🙈

But!! with the --propagate-inheritance argument specified, those ACEs get automatically propagated according to some inheritance rules. It's giving family heirloom energy. 💅

  • Inheritable (OI)(OI) ACE flags can only be applied to folders. Periodt.
  • Any inheritable ACEs applied to sub-files or folders are marked with the inherited (I) flag. Inheritable ACE(s) are applied to folders unless the no propagation (NP) flag is set.
  • When an ACE with the (OI) flag alone set is propagated to a child folder the inheritance only flag (IO) is also applied. This indicates the permissions associated with the ACE don't apply to the folder itself (only to it's child files). When applying the ACE to a child file the ACE is inherited as normal.
  • When an ace with the (CI) flag alone set is propagated to a child file there is no effect, when propagated to a child folder it is inherited as normal.
  • When an ACE that has both (OI) & (CI) flags set the ACE is inherited as normal by both folders and files.

(OI)(READ) added to parent folder

+-parent/        (OI)(READ)
| +-file.1       (I)(READ)
| +-nested/      (OI)(IO)(I)(READ)
  |   +-file.2   (I)(READ)

(CI)(READ) added to parent folder

+-parent/        (CI)(READ)
| +-file.1
| +-nested/      (CI)(I)(READ)
  |   +-file.2

(OI)(CI)(READ) added to parent folder

+-parent/        (OI)(CI)(READ)
| +-file.1       (I)(READ)
| +-nested/      (OI)(CI)(I)(READ)
  |   +-file.2   (I)(READ)

(OI)(NP)(READ) added to parent folder

+-oi_dir/        (OI)(NP)(READ)
| +-file.1       (I)(READ)
| +-nested/
|   +-file.2

(CI)(NP)(READ) added to parent folder

+-oi_dir/        (CI)(NP)(READ)
| +-file.1
| +-nested/      (I)(READ)
|   +-file.2

(OI)(CI)(NP)(READ) added to parent folder

+-parent/        (CI)(OI)(NP)(READ)
| +-file.1       (I)(READ)
| +-nested/      (I)(READ)
|   +-file.2
🚨 Files and folders with protected ACLs do not allow inheritable permissions (set with -I). Such objects will not receive ACEs flagged for inheritance with (CI) or (OI). No gatekeeping privileges for you, bestie.

💀 EXIT STATUS 💀

The smbcacls program sets the exit status depending on the success or otherwise of the operations performed. The exit status may be one of the following values. It's literally a vibe check for your command. ✨

If the operation succeeded, smbcacls returns and exit status of 0. If smbcacls couldn't connect to the specified server, or there was an error getting or setting the ACLs, an exit status of 1 is returned. If there was an error parsing any command line arguments, an exit status of 2 is returned.

🌈 VERSION 🌈

This man page is part of version 4.24.7 of the Samba suite.

👑 AUTHOR 👑

The original Samba software and related utilities were created by Andrew Tridgell. Samba is now developed by the Samba Team as an Open Source project similar to the way the Linux kernel is developed. Main character collective energy fr fr. 🫶

smbcacls was written by Andrew Tridgell and Tim Potter.

The conversion to DocBook for Samba 2.2 was done by Gerald Carter. The conversion to DocBook XML 4.2 for Samba 3.0 was done by Alexander Bokovoy.

okay that's the whole page bestie!! 💖 it's from Samba 4.24.7, dated 09/09/2026, and it's page SMBCACLS(1) — now go forth and manage those ACLs like the icon you are. slay. 🎀✨

📦 where this page comes from