What Is Force User In Samba? Users = (user] groups = [group] The function will override file or directory ownership attributes by force user. Use the appropriate credentials if the user is set as your default.
How to list active samba users?
How to Add a Samba User in Linux
- Add a user. Now let's focus on how to add a new user to Samba. ...
- Add existing local user to samba. If you already have an existing user on your system, then adding the user to samba is quite straightforward.
- Delete samba user. ...
- Conclusion. ...
How to add or delete a Samba user under Linux?
Rights Management Capabilities
- Using the “ net rpc rights ” Utility. There are two primary means of managing the rights assigned to users and groups on a Samba server. ...
- Description of Privileges. The privileges that have been implemented in Samba-3.0.11 are shown below. ...
- Privileges Suppored by Windows 2000 Domain Controllers. ...
How to manage user security in samba?
- Server host: Enter the IP address or host name for the Samba PDC server.
- Administrator user ID: Enter the administrative user ID of the Samba PDC server.
- Administrator password: Enter the password for the Samba PDC administrative user.
- Domain name: Enter the domain name of the Samba PDC server.
What is Force user?
Force-sensitives, also known as Force-users, Force wielders, or Force Adepts, were sentient or non-sentient lifeforms that possessed a strong connection to the mystical energy field known as the Force. Though the term applied to anyone who was sensitive to the spiritual energy, those who harnessed powers given by the dark side of the Force were ...
What is force create mode?
force create mode This option sets the permission bits that Samba will set when a file permission change is made. It's often used to force group permissions, as mentioned previously.
What is valid users in SMB conf?
The valid users option lists the users allowed to access the share. In this case, only the user dave is allowed to access the share. In some situations it is possible to specify that any user can access a disk share by using the guest ok parameter.
How do I add a user to Samba?
To add a new user to access a samba share you need to first create a server user account using “useradd” command and then use the same account to add the samba user. Follow the steps givenbelow to add user john and give him the access to a samba share.
What is directory mask in Samba?
You can use create mask and directory mask to set the maximum allowed permissions for newly created files and directories. The mask you set is an AND mask (it takes permissions away). [tennis] path = /srv/samba/tennis read only = No guest ok = No create mask = 640 directory mask = 750.
Where are Samba users stored?
Samba stores its encrypted passwords in a file called smbpasswd, which by default resides in the /usr/local/samba/private directory. The smbpasswd file should be guarded as closely as the passwd file; it should be placed in a directory to which only the root user has read/write access.
How do I add a valid user to Samba conf?
Solution 1: Add a local group(non UNIX) in samba database The group gid will be allocated out of the winbind range. ... Add a member to a local group. ... Change group of the shared path to local group as below. ... Run following command to list group members. ... Add the local group in file smb.Feb 8, 2017
Which command is used to add Samba user for Samba server?
sudo smbpasswd -a USEROpen up a terminal window on your Samba server (or just log in, if it's a headless machine) and issue the following command sudo smbpasswd -a USER (where USER is the username to be added). You will be prompted to enter and verify a new password for the user.Apr 2, 2018
How do I create a Samba username and password?
Adding password-secured sharesOpen a terminal window on your Samba server.Create a new group with the command sudo addgroup smbgrp.Create a new user with the command sudo useradd shares -G smbgrp.Create a Samba password for the user with the command smbpasswd -a shares.Type and verify a password for the user.More items...•Aug 27, 2016
How do I list users in Ubuntu?
Listing users in Ubuntu can be found in the /etc/passwd file. The /etc/passwd file is where all your local user information is stored. You can view the list of users in the /etc/passwd file through two commands: less and cat.
What is the flag or switch we can use with the SMB tool to list the contents of the share?
The -L option is used with the smbclient command to list all shares. Alternatively, the remote server IP address can be used in order to list shares with the -L option. In the following example, we list the shares provided by the IP address 192.168. 1.10.Apr 20, 2021
What are Pam restrictions?
There is an option in smb. conf called obey pam restrictions. The following is from the online help for this option in SWAT: When Samba is configured to enable PAM support (i.e., --with-pam ), this parameter will control whether or not Samba should obey PAM's account and session management directives.
What is map to guest bad user?
for map to guest "Bad User" is better: map to guest = Bad User - Means user logins with an invalid password are rejected, unless the username does not exist, in which case it is treated as a guest login and mapped into the guest account. As the man page says ( man smb.
What happens if you don't set a Samba password?
If you do not set Samba user passwords, users will not be able to access their shares. The command for adding a user Samba password is ( USER is the actual user name): Now the user will be able to access their Samba share using their newly created Samba user password.
Is Samba security easy?
Samba security made easy. Once you understand how best to work with Samba and user/groups, the security aspect is significantly easier. There is quite a bit more you can do to lock down your shares, but taking the steps above will get you off and running toward that coveted land of best practices.
Is Samba open source?
Image: iStock. Samba is a critical component to mixed-platform networks. If you have any intention of allowing Linux, Mac, and Windows seamlessly communicate with one another, chances are you've considered this open source service. If that's the case, you've probably also seriously considered user security. After all, you open up ...
Can you open a Samba share without user security?
If that's the case, you've probably also seriously considered user security. After all, you open up a Samba share without a nod to user security, and you run the risk of users gaining access to data they shouldn't.
What does Samba do with passwords?
What Samba does with that password—and consequently the strategy Samba will use to handle user authentication —is the arena of the security configuration option. Samba currently supports four security levels on its network: share, user , server, and domain.
What is boolean security in Samba?
This Boolean option indicates whether Samba will allow connections to a share using share-level security based solely on the individuals specified in the username option, instead of those users compiled on Samba's internal list. The default value for this option is no. You can override it per share as follows:
Why is Samba not included in Samba configuration?
[1] Having both encrypted and nonencrypted password clients on your network is one of the reasons why Samba allows you to include (or not include) various options in the Samba configuration file based on the client operating system or machine name variables.
How long is a SMB username?
Client usernames on an SMB network can be relatively long (up to 255 characters), while usernames on a Unix network often cannot be longer than eight characters. This means that an individual user can have one username on a client and another (shorter) one on the Samba server. You can get past this issue by mapping a free-form client username to a Unix username of eight or fewer characters. It is placed in a standard text file, using a format that we'll describe shortly. You can then specify the pathname to Samba with the global username map option. Be sure to restrict access to this file; make the root user the file's owner and deny write access to others (with octal permissions of 744 or 644). Otherwise, an untrusted user with access to the file can easily map his client username to the root user of the Samba server.
What is Samba domain?
Samba becomes a member of a Windows NT domain and uses one of the domain's domain controllers —either the PDC or a BDC—to perform authentication. Once authenticated, the user is given a special token that allows her access to any share with appropriate access rights. With this token, the domain controller will not have to revalidate the user's password each time she attempts to access another share within the domain. The domain controller can be a Windows NT/2000 PDC or BDC, or Samba acting as a Windows NT PDC.
Where is the passwd program in Samba?
This option defaults to the standard passwd program, usually located in the /bin directory. The %u variable is typically used as the requesting user when the command is executed. The actual handling of input and output to this program during execution is handled through the passwd chat option. Section 9.4.3 earlier in this chapter covers this option in detail.
Where is Samba password stored?
Samba stores its encrypted passwords in a file called smbpasswd , which by default resides in the /usr/local/samba/private directory . The smbpasswd file should be guarded as closely as the Unix system's password file (either /etc/passwd or /etc/shadow ). Only the root user should have read/write access to the private directory, and no other users should have access to it at all. In addition, the smbpasswd file should have all access denied to all users except for root. When things are set up for good security, long listings of the private directory and smbpasswd file look like the following:
What is Samba conf?
The Samba suite includes a number of different programs. Some of them operate in a client mode, others are server daemons that provide various services to its clients. The smb.conf file is processed in the following way: The Samba suite's client applications read their configuration only once.
Why does Samba support name mangling?
Samba supports name mangling so that DOS and Windows clients can use files that don't conform to the 8.3 format. It can also be set to adjust the case of 8.3 format filenames.
How does Samba work with LDAP?
By default, Samba as a Domain Controller with an LDAP backend needs to use the Unix-style NSS subsystem to access user and group information. Due to the way Unix stores user information in /etc/passwd and /etc/group this inevitably leads to inefficiencies. One important question a user needs to know is the list of groups he is member of. The plain UNIX model involves a complete enumeration of the file /etc/group and its NSS counterparts in LDAP. UNIX has optimized functions to enumerate group membership. Sadly, other functions that are used to deal with user and group attributes lack such optimization.#N#To make Samba scale well in large environments, the ldapsam:trusted = yes option assumes that the complete user and group database that is relevant to Samba is stored in LDAP with the standard posixAccount/posixGroup attributes. It further assumes that the Samba auxiliary object classes are stored together with the POSIX data in the same LDAP object. If these assumptions are met, ldapsam:trusted = yes can be activated and Samba can bypass the NSS system to query user group memberships. Optimized LDAP queries can greatly speed up domain logon and administration tasks. Depending on the size of the LDAP database a factor of 100 or more for common queries is easily achieved.#N#Default: ldapsam:trusted = no
What is smbd(8) boolean?
This boolean parameter controls the behaviour of smbd(8) when receiving a protocol request of "open for execution" from a Windows client. With Samba 3.6 and older, the execution right in the ACL was not checked, so a client could execute a file even if it did not have execute rights on the file. In Samba 4.0, this has been fixed, so that by default, i.e. when this parameter is set to "False", "open for execution" is now denied when execution permissions are not present.#N#If this parameter is set to "True", Samba does not check execute permissions on "open for execution", thus re-establishing the behaviour of Samba 3.6. This can be useful to smoothen upgrades from older Samba versions to 4.0 and newer. This setting is not meant to be used as a permanent setting, but as a temporary relief: It is recommended to fix the permissions in the ACLs and reset this parameter to the default after a certain transition period.#N#Default: acl allow execute always = no
What is Samba 3.0.23?
Starting with Samba version 3.0.23 the capability for non-root users to add, modify, and delete their own share definitions has been added. This capability is called usershares and is controlled by a set of parameters in the [global] section of the smb.conf. The relevant parameters are :
What is smb.conf file?
The smb.conf file is a configuration file for the Samba suite. smb.conf contains runtime configuration information for the Samba programs. The complete description of the file format and possible parameters held within are here for reference purposes.
Where are TDB files stored in Samba?
Usually, most of the TDB files are stored in the lock directory. Since Samba 3.4.0, it is possible to differentiate between TDB files with persistent data and TDB files with non-persistent data using the state directory and the cache directory options.#N#This option specifies the directory for storing TDB files containing non-persistent data that will be kept across service restarts. The directory should be placed on persistent storage, but the data can be safely deleted by an administrator.#N#Default: cache directory = $ {prefix}/var/cache#N#Example: cache directory = /var/run/samba/locks/cache
dperson commented on Nov 13, 2019
That user won't necessarily exist in other containers and/or the host system (if it does it will likely have the wrong UID/GID), so I'm not sure that's what you really want.
dperson commented on Nov 13, 2019
It doesn't matter if the force statements are in place or not users inside the container don't match up with those outside unless you do extra work to make them do so (even if the user/group names are the same the IDs will be different).
dperson commented on Nov 14, 2019
The smbuser and smb group only exist in the container. Outside the container their actual numeric user ID and group ID will refer to a different or non-existent user/group. The USERID and GROUPID let you make the IDs be whatever you want to match something outside the container.
BobSammers commented on May 29, 2020
I was bitten by this as well, although I fully understand dperson's reluctance to support an ever-expanding list of features.
mariuszskon commented on Oct 15, 2020
To others stumbling across this, I found this solution by @DrDOIS from here. It seems to work correctly to reset the forcing of user and group, such that you do not need a separate hack for each share or each user.
Forcing User Or Group Ownership
- In the file /etc/samba/smb.confyou can use the directive: This will override the normal file ownership attributes for file or directory access. Be default, the effective user credentials are used. By using either (or both) of the above directives, the associated credential can be coerced to a specific value. Thus, all the file accesses will be perf...
Use The Directory Access Permissions
- Consider the /tmp director: it is a scratchpad which allows multiple users to create, modify or delete files. To prevent user A from deleting a file owned by user B, the directory has the sticky bit set: Notice the t flag of the permissions: this indicates the “sticky” bit is set for the directory. Any user can create files in this directory, but only the owning user can delete the entry; without the s…
Note
- The setgid method described above also works if the setuid bit is used instead. In the chmod step, do this instead: You could also override both the file ownership and group membership like this: Although a fascinating capability, this may have limited utility.
Use Access Control Lists
- Access control lists, or ACL, are file system features where an extra set of file attributes stored in addition to the normal Linux file owner/group/other permissions. Using ACL allows a very fine-grained control over the exact type of access to be granted to a given access type. The SAMBA file system implementation on Linux supports access control lists, but the feature must be expli…
Security by User Or Group
Controlling Access to Shares
- You’ll want to ensure particular users cannot access any Samba share on your server; those users are root, bin, daemon, adm, sync, shutdown, halt, mail, news, uucp, or operator. We block their access in the [global]define like so: invalid users = root bin daemon adm sync shutdown halt mail news uucp operator To block specific groups in the [global] definition, the invalid groups option …
Setting Samba Passwords
- One of the most commonly overlooked steps in setting up Samba is adding passwords for users. If you do not set Samba user passwords, users will not be able to access their shares. The command for adding a user Samba password is (USERis the actual user name): smbpasswd -a USER Now the user will be able to access their Samba share using their newly c...
Samba Security Made Easy
- Once you understand how best to work with Samba and user/groups, the security aspect is significantly easier. There is quite a bit more you can do to lock down your shares, but taking the steps above will get you off and running toward that coveted land of best practices.