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+<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Chapter 13. File, Directory and Share Access Controls</title><link rel="stylesheet" href="samba.css" type="text/css"><meta name="generator" content="DocBook XSL Stylesheets V1.60.1"><link rel="home" href="index.html" title="SAMBA Project Documentation"><link rel="up" href="optional.html" title="Part III. Advanced Configuration"><link rel="previous" href="groupmapping.html" title="Chapter 12. Mapping MS Windows and Unix Groups"><link rel="next" href="locking.html" title="Chapter 14. File and Record Locking"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 13. File, Directory and Share Access Controls</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="groupmapping.html">Prev</a> </td><th width="60%" align="center">Part III. Advanced Configuration</th><td width="20%" align="right"> <a accesskey="n" href="locking.html">Next</a></td></tr></table><hr></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="AccessControls"></a>Chapter 13. File, Directory and Share Access Controls</h2></div><div><div class="author"><h3 class="author"><span class="firstname">John</span> <span class="othername">H.</span> <span class="surname">Terpstra</span></h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><tt class="email">&lt;<a href="mailto:jht@samba.org">jht@samba.org</a>&gt;</tt></p></div></div></div></div><div><div class="author"><h3 class="author"><span class="firstname">Jeremy</span> <span class="surname">Allison</span></h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><tt class="email">&lt;<a href="mailto:jra@samba.org">jra@samba.org</a>&gt;</tt></p></div></div></div></div><div><p class="pubdate">May 10, 2003</p></div></div><div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><a href="AccessControls.html#id2919879">Features and Benefits</a></dt><dt><a href="AccessControls.html#id2920005">File System Access Controls</a></dt><dd><dl><dt><a href="AccessControls.html#id2920023">MS Windows NTFS Comparison with Unix File Systems</a></dt><dt><a href="AccessControls.html#id2916939">Managing Directories</a></dt><dt><a href="AccessControls.html#id2917034">File and Directory Access Control</a></dt></dl></dd><dt><a href="AccessControls.html#id2917441">Share Definition Access Controls</a></dt><dd><dl><dt><a href="AccessControls.html#id2917469">User and Group Based Controls</a></dt><dt><a href="AccessControls.html#id2917741">File and Directory Permissions Based Controls</a></dt><dt><a href="AccessControls.html#id2917987">Miscellaneous Controls</a></dt></dl></dd><dt><a href="AccessControls.html#id2922570">Access Controls on Shares</a></dt><dd><dl><dt><a href="AccessControls.html#id2922641">Share Permissions Management</a></dt></dl></dd><dt><a href="AccessControls.html#id2922940">MS Windows Access Control Lists and Unix Interoperability</a></dt><dd><dl><dt><a href="AccessControls.html#id2922948">Managing UNIX permissions Using NT Security Dialogs</a></dt><dt><a href="AccessControls.html#id2922986">Viewing File Security on a Samba Share</a></dt><dt><a href="AccessControls.html#id2923065">Viewing file ownership</a></dt><dt><a href="AccessControls.html#id2923187">Viewing File or Directory Permissions</a></dt><dt><a href="AccessControls.html#id2923415">Modifying file or directory permissions</a></dt><dt><a href="AccessControls.html#id2923567">Interaction with the standard Samba create mask
+ parameters</a></dt><dt><a href="AccessControls.html#id2923897">Interaction with the standard Samba file attribute
+ mapping</a></dt></dl></dd><dt><a href="AccessControls.html#id2923972">Common Errors</a></dt><dd><dl><dt><a href="AccessControls.html#id2923986">Users can not write to a public share</a></dt><dt><a href="AccessControls.html#id2924365">I have set force user and samba still makes root the owner of all the files
+ I touch!</a></dt></dl></dd></dl></div><p>
+Advanced MS Windows users are frequently perplexed when file, directory and share manipulation of
+resources shared via Samba do not behave in the manner they might expect. MS Windows network
+adminstrators are often confused regarding network access controls and what is the best way to
+provide users with the type of access they need while protecting resources from the consequences
+of untoward access capabilities.
+</p><p>
+Unix administrators frequently are not familiar with the MS Windows environment and in particular
+have difficulty in visualizing what the MS Windows user wishes to achieve in attempts to set file
+and directory access permissions.
+</p><p>
+The problem lies in the differences in how file and directory permissions and controls work
+between the two environments. This difference is one that Samba can not completely hide, even
+though it does try to make the chasm transparent.
+</p><p>
+POSIX Access Control List technology has been available (along with Extended Attributes)
+for Unix for many years, yet there is little evidence today of any significant use. This
+explains to some extent the slow adoption of ACLs into commercial Linux products. MS Windows
+administrators are astounded at this given that ACLs were a foundational capability of the now
+decade old MS Windows NT operating system.
+</p><p>
+The purpose of this chapter is to present each of the points of control that are possible with
+Samba-3 in the hope that this will help the network administrator to find the optimum method
+for delivering the best environment for MS Windows desktop users.
+</p><p>
+This is an opportune point to mention that it should be borne in mind that Samba was created to
+provide a means of interoperability and interchange of data between two operating environments
+that are quite different. It was never the intent to make Unix/Linux like MS Windows NT. Instead
+the purpose was an is to provide a sufficient level of exchange of data between the two environments.
+What is available today extends well beyond early plans and expections, yet the gap continues to
+shrink.
+</p><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2919879"></a>Features and Benefits</h2></div></div><div></div></div><p>
+ Samba offers a lot of flexibility in file system access management. These are the key access control
+ facilities present in Samba today:
+ </p><div class="itemizedlist"><p class="title"><b>Samba Access Control Facilities</b></p><ul type="disc"><li><p>
+ <span class="emphasis"><em>Unix File and Directory Permissions</em></span>
+ </p><p>
+ Samba honours and implements Unix file system access controls. Users
+ who access a Samba server will do so as a particular MS Windows user.
+ This information is passed to the Samba server as part of the logon or
+ connection setup process. Samba uses this user identity to validate
+ whether or not the user should be given access to file system resources
+ (files and directories). This chapter provides an overview for those
+ to whom the Unix permissions and controls are a little strange or unknown.
+ </p></li><li><p>
+ <span class="emphasis"><em>Samba Share Definitions</em></span>
+ </p><p>
+ In configuring share settings and controls in the <tt class="filename">smb.conf</tt> file
+ the network administrator can exercise over-rides to native file
+ system permissions and behaviours. This can be handy and convenient
+ to affect behaviour that is more like what MS Windows NT users expect
+ but it is seldom the <span class="emphasis"><em>best</em></span> way to achieve this.
+ The basic options and techniques are described herein.
+ </p></li><li><p>
+ <span class="emphasis"><em>Samba Share ACLs</em></span>
+ </p><p>
+ Just like it is possible in MS Windows NT to set ACLs on shares
+ themselves, so it is possible to do this in Samba.
+ Very few people make use of this facility, yet it remains on of the
+ easiest ways to affect access controls (restrictions) and can often
+ do so with minimum invasiveness compared with other methods.
+ </p></li><li><p>
+ <span class="emphasis"><em>MS Windows ACLs through Unix POSIX ACLs</em></span>
+ </p><p>
+ The use of POSIX ACLs on Unix/Linux is possible ONLY if the underlying
+ operating system supports them. If not, then this option will not be
+ available to you. Current Unix technology platforms have native support
+ for POSIX ACLs. There are patches for the Linux kernel that provide
+ this also. Sadly, few Linux paltforms ship today with native ACLs and
+ Extended Attributes enabled. This chapter has pertinent information
+ for users of platforms that support them.
+ </p></li></ul></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2920005"></a>File System Access Controls</h2></div></div><div></div></div><p>
+Perhaps the most important recognition to be made is the simple fact that MS Windows NT4 / 200x / XP
+implement a totally divergent file system technology from what is provided in the Unix operating system
+environment. Firstly we should consider what the most significant differences are, then we shall look
+at how Samba helps to bridge the differences.
+</p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2920023"></a>MS Windows NTFS Comparison with Unix File Systems</h3></div></div><div></div></div><p>
+ Samba operates on top of the Unix file system. This means it is subject to Unix file system conventions
+ and permissions. It also means that if the MS Windows networking environment requires file system
+ behaviour that differs from unix file system behaviour then somehow Samba is responsible for emulating
+ that in a transparent and consistent manner.
+ </p><p>
+ It is good news that Samba does this to a very large extent and on top of that provides a high degree
+ of optional configuration to over-ride the default behaviour. We will look at some of these over-rides,
+ but for the greater part we will stay withing the bounds of default behaviour. Those wishing to explore
+ to depths of control ability should review the <tt class="filename">smb.conf</tt> man page.
+ </p><div class="variablelist"><p class="title"><b>File System Feature Comparison</b></p><dl><dt><span class="term">Name Space</span></dt><dd><p>
+ MS Windows NT4 / 200x/ XP files names may be up to 254 characters long, Unix file names
+ may be 1023 characters long. In MS Windows file extensions indicate particular file types,
+ in Unix this is not so rigorously observed as all names are considered arbitrary.
+ </p><p>
+ What MS Windows calls a Folder, Unix calls a directory,
+ </p></dd><dt><span class="term">Case Sensitivity</span></dt><dd><p>
+ MS Windows file names are generally Upper Case if made up of 8.3 (ie: 8 character file name
+ and 3 character extension. If longer than 8.3 file names are Case Preserving, and Case
+ Insensitive.
+ </p><p>
+ Unix file and directory names are Case Sensitive and Case Preserving. Samba implements the
+ MS Windows file name behaviour, but it does so as a user application. The Unix file system
+ provides no mechanism to perform case insensitive file name lookups. MS Windows does this
+ by default. This means that Samba has to carry the processing overhead to provide features
+ that are NOT native to the Unix operating system environment.
+ </p><p>
+ Consider the following, all are unique Unix names but one single MS Windows file name:
+ <tt class="computeroutput">
+ MYFILE.TXT
+ MyFile.txt
+ myfile.txt
+ </tt>
+ So clearly, In an MS Windows file name space these three files CAN NOT co-exist! But in Unix
+ they can. So what should Samba do if all three are present? Answer, the one that is lexically
+ first will be accessible to MS Windows users, the others are invisible and unaccessible - any
+ other solution would be suicidal.
+ </p></dd><dt><span class="term">Directory Separators</span></dt><dd><p>
+ MS Windows and DOS uses the back-slash '\' as a directory delimiter, Unix uses the forward-slash '/'
+ as it's directory delimiter. This is transparently handled by Samba.
+ </p></dd><dt><span class="term">Drive Identification</span></dt><dd><p>
+ MS Windows products support a notion of drive letters, like <b class="command">C:</b> to represent
+ disk partitions. Unix has NO concept if separate identifiers for file partitions since each
+ such file system is <tt class="filename">mounted</tt> to become part of the over-all directory tree.
+ The Unix directory tree begins at '/', just like the root of a DOS drive is specified like
+ <b class="command">C:\</b>.
+ </p></dd><dt><span class="term">File Naming Conventions</span></dt><dd><p>
+ MS Windows generally never experiences file names that begin with a '.', while in Unix these
+ are commonly found in a user's home directory. Files that begin with a '.' are typically
+ either start up files for various Unix applications, or they may be files that contain
+ start-up configuration data.
+ </p></dd><dt><span class="term">Links and Short-Cuts</span></dt><dd><p>
+ MS Windows make use of &quot;links and Short-Cuts&quot; that are actually special types of files that will
+ redirect an attempt to execute the file to the real location of the file. Unix knows of file and directory
+ links, but they are entirely different from what MS Windows users are used to.
+ </p><p>
+ Symbolic links are files in Unix that contain the actual location of the data (file OR directory). An
+ operation (like read or write) will operate directly on the file referenced. Symbolic links are also
+ referred to as 'soft links'. A hard link is something that MS Windows is NOT familiar with. It allows
+ one physical file to be known simulataneously by more than one file name.
+ </p></dd></dl></div><p>
+ There are many other subtle differences that may cause the MS Windows administrator some temporary discomfort
+ in the process of becoming familiar with Unix/Linux. These are best left for a text that is dedicated to the
+ purpose of Unix/Linux training/education.
+ </p></div><div xmlns:ns29="" class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2916939"></a>Managing Directories</h3></div></div><div></div></div><ns29:p>
+ There are three basic operations for managing directories, <b class="command">create, delete, rename</b>.
+ </ns29:p><div class="table"><a name="id2916957"></a><p class="title"><b>Table 13.1. Managing directories with unix and windows</b></p><table summary="Managing directories with unix and windows" border="1"><colgroup><col><col><col></colgroup><thead><tr><th align="center">Action</th><th align="center">MS Windows Command</th><th align="center">Unix Command</th></tr></thead><tbody><tr><td align="center">create</td><td align="center">md folder</td><td align="center">mkdir folder</td></tr><tr><td align="center">delete</td><td align="center">rd folder</td><td align="center">rmdir folder</td></tr><tr><td align="center">rename</td><td align="center">rename oldname newname</td><td align="center">mv oldname newname</td></tr></tbody></table></div><ns29:p>
+ </ns29:p></div><div xmlns:ns30="" class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2917034"></a>File and Directory Access Control</h3></div></div><div></div></div><p>
+ The network administrator is strongly advised to read foundational training manuals and reference materials
+ regarding file and directory permissions maintenance. Much can be achieved with the basic Unix permissions
+ without having to resort to more complex facilities like POSIX Access Control Lists (ACLs) or Extended
+ Attributes (EAs).
+ </p><ns30:p>
+ Unix/Linux file and directory access permissions invloves setting three (3) primary sets of data and one (1) control set.
+ A Unix file listing looks as follows:-
+
+ </ns30:p><pre class="screen">
+ <tt class="prompt">jht@frodo:~/stuff&gt; </tt><b class="userinput"><tt>ls -la</tt></b>
+ total 632
+ drwxr-xr-x 13 jht users 816 2003-05-12 22:56 .
+ drwxr-xr-x 37 jht users 3800 2003-05-12 22:29 ..
+ d--------- 2 jht users 48 2003-05-12 22:29 muchado00
+ d--x--x--x 2 jht users 48 2003-05-12 22:29 muchado01
+ dr-xr-xr-x 2 jht users 48 2003-05-12 22:29 muchado02
+ drwxrwxrwx 2 jht users 48 2003-05-12 22:29 muchado03
+ drw-rw-rw- 2 jht users 48 2003-05-12 22:29 muchado04
+ d-w--w--w- 2 jht users 48 2003-05-12 22:29 muchado05
+ dr--r--r-- 2 jht users 48 2003-05-12 22:29 muchado06
+ drwxrwxrwt 2 jht users 48 2003-05-12 22:29 muchado07
+ drwsrwsrwx 2 jht users 48 2003-05-12 22:29 muchado08
+ ---------- 1 jht users 1242 2003-05-12 22:31 mydata00.lst
+ ---x--x--x 1 jht users 1674 2003-05-12 22:33 mydata01.lst
+ --w--w--w- 1 jht users 7754 2003-05-12 22:33 mydata02.lst
+ --wx-wx-wx 1 jht users 260179 2003-05-12 22:33 mydata03.lst
+ -r--r--r-- 1 jht users 21017 2003-05-12 22:32 mydata04.lst
+ -r-xr-xr-x 1 jht users 206339 2003-05-12 22:32 mydata05.lst
+ -rw-rw-rw- 1 jht users 41105 2003-05-12 22:32 mydata06.lst
+ -rwxrwxrwx 1 jht users 19312 2003-05-12 22:32 mydata07.lst
+ <tt class="prompt">jht@frodo:~/stuff&gt;</tt>
+ </pre><ns30:p>
+ </ns30:p><p>
+ The columns above represent (from left to right): permissions, no blocks used, owner, group, size (bytes), access date, access time, file name.
+ </p><ns30:p>
+ The permissions field is made up of:
+
+ </ns30:p><pre class="programlisting">
+ <i><span class="comment"> JRV: Put this into a diagram of some sort</span></i>
+ [ type ] [ users ] [ group ] [ others ] [File, Directory Permissions]
+ [ d | l ] [ r w x ] [ r w x ] [ r w x ]
+ | | | | | | | | | | |
+ | | | | | | | | | | |-----&gt; Can Execute, List files
+ | | | | | | | | | |-------&gt; Can Write, Create files
+ | | | | | | | | |---------&gt; Can Read, Read files
+ | | | | | | | |---------------&gt; Can Execute, List files
+ | | | | | | |-----------------&gt; Can Write, Create files
+ | | | | | |-------------------&gt; Can Read, Read files
+ | | | | |-------------------------&gt; Can Execute, List files
+ | | | |---------------------------&gt; Can Write, Create files
+ | | |-----------------------------&gt; Can Read, Read files
+ | |-----------------------------------&gt; Is a symbolic Link
+ |---------------------------------------&gt; Is a directory
+ </pre><ns30:p>
+ </ns30:p><ns30:p>
+ Any bit flag may be unset. An unset bit flag is the equivalent of 'Can NOT' and is represented as a '-' character.
+
+ </ns30:p><div class="example"><a name="id2917362"></a><p class="title"><b>Example 13.1. Example File</b></p><pre class="programlisting">
+ -rwxr-x--- Means: The owner (user) can read, write, execute
+ the group can read and execute
+ everyone else can NOT do anything with it
+ </pre></div><ns30:p>
+
+ </ns30:p><p>
+ Additional posibilities in the [type] field are: c = character device, b = block device, p = pipe device, s = Unix Domain Socket.
+ </p><p>
+ The letters `rwxXst' set permissions for the user, group and others as: read (r), write (w), execute (or access for directories) (x),r
+ execute only if the file is a directory or already has execute permission for some user (X), set user or group ID on execution (s),
+ sticky (t).
+ </p><p>
+ When the sticky bit is set on a directory, files in that directory may be unlinked (deleted) or renamed only by root or their owner.
+ Without the sticky bit, anyone able to write to the directory can delete or rename files. The sticky bit is commonly found on
+ directories, such as /tmp, that are world-writable.
+ </p><p>
+ When the set user or group ID bit (s) is set on a directory, then all files created within it will be owned by the user and/or
+ group whose 'set user or group' bit is set. This can be very helpful in setting up directories that for which it is desired that
+ all users who are in a group should be able to write to and read from a file, particularly when it is undesirable for that file
+ to be exclusively owned by a user who's primary group is not the group that all such users belong to.
+ </p><p>
+ When a directory is set <tt class="constant">drw-r-----</tt> this means that the owner can read and create (write) files in it, but because
+ the (x) execute flags are not set files can not be listed (seen) in the directory by anyone. The group can read files in the
+ directory but can NOT create new files. NOTE: If files in the directory are set to be readable and writable for the group, then
+ group members will be able to write to (or delete) them.
+ </p></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2917441"></a>Share Definition Access Controls</h2></div></div><div></div></div><p>
+The following parameters in the <tt class="filename">smb.conf</tt> file sections that define a share control or affect access controls.
+Before using any of the following options please refer to the man page for <tt class="filename">smb.conf</tt>.
+</p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2917469"></a>User and Group Based Controls</h3></div></div><div></div></div><p>
+ User and group based controls can prove very useful. In some situations it is distinctly desirable to affect all
+ file system operations as if a single user is doing this, the use of the <i class="parameter"><tt>force user</tt></i> and
+ <i class="parameter"><tt>force group</tt></i> behaviour will achieve this. In other situations it may be necessary to affect a
+ paranoia level of control to ensure that only particular authorised persons will be able to access a share or
+ it's contents, here the use of the <i class="parameter"><tt>valid users</tt></i> or the <i class="parameter"><tt>invalid users</tt></i> may
+ be most useful.
+ </p><p>
+ As always, it is highly advisable to use the least difficult to maintain and the least ambiguous method for
+ controlling access. Remember, that when you leave the scene someone else will need to provide assistance and
+ if that person finds too great a mess, or if they do not understand what you have done then there is risk of
+ Samba being removed and an alternative solution being adopted.
+ </p><div class="table"><a name="id2917528"></a><p class="title"><b>Table 13.2. User and Group Based Controls</b></p><table summary="User and Group Based Controls" border="1"><colgroup><col><col></colgroup><thead><tr><th align="center">Control Parameter</th><th align="center">Description - Action - Notes</th></tr></thead><tbody><tr><td>admin users</td><td><p>
+ List of users who will be granted administrative privileges on the share.
+ They will do all file operations as the super-user (root).
+ Any user in this list will be able to do anything they like on the share,
+ irrespective of file permissions.
+ </p></td></tr><tr><td>force group</td><td><p>
+ Specifies a UNIX group name that will be assigned as the default primary group
+ for all users connecting to this service.
+ </p></td></tr><tr><td>force user</td><td><p>
+ Specifies a UNIX user name that will be assigned as the default user for all users connecting to this service.
+ This is useful for sharing files. Incorrect use can cause security problems.
+ </p></td></tr><tr><td>guest ok</td><td><p>
+ If this parameter is set for a service, then no password is required to connect to the service. Privileges will be
+ those of the guest account.
+ </p></td></tr><tr><td>invalid users</td><td><p>
+ List of users that should not be allowed to login to this service.
+ </p></td></tr><tr><td>only user</td><td><p>
+ Controls whether connections with usernames not in the user list will be allowed.
+ </p></td></tr><tr><td>read list</td><td><p>
+ List of users that are given read-only access to a service. Users in this list
+ will not be given write access, no matter what the read only option is set to.
+ </p></td></tr><tr><td>username</td><td><p>
+ Refer to the <tt class="filename">smb.conf</tt> man page for more information - this is a complex and potentially misused parameter.
+ </p></td></tr><tr><td>valid users</td><td><p>
+ List of users that should be allowed to login to this service.
+ </p></td></tr><tr><td>write list</td><td><p>
+ List of users that are given read-write access to a service.
+ </p></td></tr></tbody></table></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2917741"></a>File and Directory Permissions Based Controls</h3></div></div><div></div></div><p>
+ The following file and directory permission based controls, if misused, can result in considerable difficulty to
+ diagnose the cause of mis-configuration. Use them sparingly and carefully. By gradually introducing each one by one
+ undesirable side-effects may be detected. In the event of a problem, always comment all of them out and then gradually
+ re-instroduce them in a controlled fashion.
+ </p><div class="table"><a name="id2917761"></a><p class="title"><b>Table 13.3. File and Directory Permission Based Controls</b></p><table summary="File and Directory Permission Based Controls" border="1"><colgroup><col><col></colgroup><thead><tr><th align="center">Control Parameter</th><th align="center">Description - Action - Notes</th></tr></thead><tbody><tr><td>create mask</td><td><p>
+ Refer to the <tt class="filename">smb.conf</tt> man page.
+ </p></td></tr><tr><td>directory mask</td><td><p>
+ The octal modes used when converting DOS modes to UNIX modes when creating UNIX directories.
+ See also: directory security mask.
+ </p></td></tr><tr><td>dos filemode</td><td><p>
+ Enabling this parameter allows a user who has write access to the file to modify the permissions on it.
+ </p></td></tr><tr><td>force create mode</td><td><p>
+ This parameter specifies a set of UNIX mode bit permissions that will always be set on a file created by Samba.
+ </p></td></tr><tr><td>force directory mode</td><td><p>
+ This parameter specifies a set of UNIX mode bit permissions that will always be set on a directory created by Samba.
+ </p></td></tr><tr><td>force directory security mode</td><td><p>
+ Controls UNIX permission bits modified when a Windows NT client is manipulating UNIX permissions on a directory
+ </p></td></tr><tr><td>force security mode</td><td><p>
+ Controls UNIX permission bits modified when a Windows NT client manipulates UNIX permissions.
+ </p></td></tr><tr><td>hide unreadable</td><td><p>
+ Prevents clients from seeing the existance of files that cannot be read.
+ </p></td></tr><tr><td>hide unwriteable files</td><td><p>
+ Prevents clients from seeing the existance of files that cannot be written to. Unwriteable directories are shown as usual.
+ </p></td></tr><tr><td>nt acl support</td><td><p>
+ This parameter controls whether smbd will attempt to map UNIX permissions into Windows NT access control lists.
+ </p></td></tr><tr><td>security mask</td><td><p>
+ Controls UNIX permission bits modified when a Windows NT client is manipulating the UNIX permissions on a file.
+ </p></td></tr></tbody></table></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2917987"></a>Miscellaneous Controls</h3></div></div><div></div></div><p>
+ The following are documented because of the prevalence of administrators creating inadvertant barriers to file
+ access by not understanding the full implications of <tt class="filename">smb.conf</tt> file settings.
+ </p><div class="table"><a name="id2918008"></a><p class="title"><b>Table 13.4. Other Controls</b></p><table summary="Other Controls" border="1"><colgroup><col><col></colgroup><thead><tr><th align="center">Control Parameter</th><th align="center">Description - Action - Notes</th></tr></thead><tbody><tr><td>case sensitive, default case, short preserve case</td><td><p>
+ This means that all file name lookup will be done in a case sensitive manner.
+ Files will be created with the precise filename Samba received from the MS Windows client.
+ </p></td></tr><tr><td>csc policy</td><td><p>
+ Client Side Caching Policy - parallels MS Windows client side file caching capabilities.
+ </p></td></tr><tr><td>dont descend</td><td><p>
+ Allows to specify a comma-delimited list of directories that the server should always show as empty.
+ </p></td></tr><tr><td>dos filetime resolution</td><td><p>
+ This option is mainly used as a compatibility option for Visual C++ when used against Samba shares.
+ </p></td></tr><tr><td>dos filetimes</td><td><p>
+ DOS and Windows allows users to change file time stamps if they can write to the file. POSIX semantics prevent this.
+ This options allows DOS and Windows behaviour.
+ </p></td></tr><tr><td>fake oplocks</td><td><p>
+ Oplocks are the way that SMB clients get permission from a server to locally cache file operations. If a server grants an
+ oplock then the client is free to assume that it is the only one accessing the file and it will aggressively cache file data.
+ </p></td></tr><tr><td>hide dot files, hide files, veto files</td><td><p>
+ Note: MS Windows Explorer allows over-ride of files marked as hidden so they will still be visible.
+ </p></td></tr><tr><td>read only</td><td><p>
+ If this parameter is yes, then users of a service may not create or modify files in the service's directory.
+ </p></td></tr><tr><td>veto files</td><td><p>
+ List of files and directories that are neither visible nor accessible.
+ </p></td></tr></tbody></table></div></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2922570"></a>Access Controls on Shares</h2></div></div><div></div></div><p>
+ This section deals with how to configure Samba per share access control restrictions.
+ By default samba sets no restrictions on the share itself. Restrictions on the share itself
+ can be set on MS Windows NT4/200x/XP shares. This can be a very effective way to limit who can
+ connect to a share. In the absence of specific restrictions the default setting is to allow
+ the global user <tt class="constant">Everyone</tt> Full Control (ie: Full control, Change and Read).
+ </p><p>
+ At this time Samba does NOT provide a tool for configuring access control setting on the Share
+ itself. Samba does have the capacity to store and act on access control settings, but the only
+ way to create those settings is to use either the NT4 Server Manager or the Windows 200x MMC for
+ Computer Management.
+ </p><p>
+ Samba stores the per share access control settings in a file called <tt class="filename">share_info.tdb</tt>.
+ The location of this file on your system will depend on how samba was compiled. The default location
+ for samba's tdb files is under <tt class="filename">/usr/local/samba/var</tt>. If the <tt class="filename">tdbdump</tt>
+ utility has been compiled and installed on your system then you can examine the contents of this file
+ by: <b class="userinput"><tt>tdbdump share_info.tdb</tt></b>.
+ </p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2922641"></a>Share Permissions Management</h3></div></div><div></div></div><p>
+ The best tool for the task is platform dependant. Choose the best tool for your environmemt.
+ </p><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2922654"></a>Windows NT4 Workstation/Server</h4></div></div><div></div></div><p>
+ The tool you need to use to manage share permissions on a Samba server is the NT Server Manager.
+ Server Manager is shipped with Windows NT4 Server products but not with Windows NT4 Workstation.
+ You can obtain the NT Server Manager for MS Windows NT4 Workstation from Microsoft - see details below.
+ </p><div class="procedure"><p class="title"><b>Procedure 13.1. Instructions</b></p><ol type="1"><li><p>
+ Launch the <span class="application">NT4 Server Manager</span>, click on the Samba server you want to administer, then from the menu
+ select <span class="guimenu">Computer</span>, then click on the <span class="guimenuitem">Shared Directories</span> entry.
+ </p></li><li><p>
+ Now click on the share that you wish to manage, then click on the <span class="guilabel">Properties</span> tab, next click on
+ the <span class="guilabel">Permissions</span> tab. Now you can add or change access control settings as you wish.
+ </p></li></ol></div></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2922737"></a>Windows 200x/XP</h4></div></div><div></div></div><p>
+ On <span class="application">MS Windows NT4/200x/XP</span> system access control lists on the share itself are set using native
+ tools, usually from filemanager. For example, in Windows 200x: right click on the shared folder,
+ then select <span class="guimenuitem">Sharing</span>, then click on <span class="guilabel">Permissions</span>. The default
+ Windows NT4/200x permission allows <span class="emphasis"><em>Everyone</em></span> Full Control on the Share.
+ </p><p>
+ MS Windows 200x and later all comes with a tool called the <span class="application">Computer Management</span> snap-in for the
+ Microsoft Management Console (MMC). This tool is located by clicking on <tt class="filename">Control Panel -&gt;
+ Administrative Tools -&gt; Computer Management</tt>.
+ </p><div class="procedure"><p class="title"><b>Procedure 13.2. Instructions</b></p><ol type="1"><li><p>
+ After launching the MMC with the Computer Management snap-in, click on the menu item <span class="guimenuitem">Action</span>,
+ select <span class="guilabel">Connect to another computer</span>. If you are not logged onto a domain you will be prompted
+ to enter a domain login user identifier and a password. This will authenticate you to the domain.
+ If you where already logged in with administrative privilidge this step is not offered.
+ </p></li><li><p>
+ If the Samba server is not shown in the <span class="guilabel">Select Computer</span> box, then type in the name of the target
+ Samba server in the field <span class="guilabel">Name:</span>. Now click on the <span class="guibutton">[+]</span> next to
+ <span class="guilabel">System Tools</span>, then on the <span class="guibutton">[+]</span> next to <span class="guilabel">Shared Folders</span> in the
+ left panel.
+ </p></li><li><p>
+ Now in the right panel, double-click on the share you wish to set access control permissions on.
+ Then click on the tab <span class="guilabel">Share Permissions</span>. It is now possible to add access control entities
+ to the shared folder. Do NOT forget to set what type of access (full control, change, read) you
+ wish to assign for each entry.
+ </p></li></ol></div><div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Warning</h3><p>
+ Be careful. If you take away all permissions from the <tt class="constant">Everyone</tt> user without removing this user
+ then effectively no user will be able to access the share. This is a result of what is known as
+ ACL precedence. ie: Everyone with <span class="emphasis"><em>no access</em></span> means that MaryK who is part of the group
+ <tt class="constant">Everyone</tt> will have no access even if this user is given explicit full control access.
+ </p></div></div></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2922940"></a>MS Windows Access Control Lists and Unix Interoperability</h2></div></div><div></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2922948"></a>Managing UNIX permissions Using NT Security Dialogs</h3></div></div><div></div></div><p>Windows NT clients can use their native security settings
+ dialog box to view and modify the underlying UNIX permissions.</p><p>Note that this ability is careful not to compromise
+ the security of the UNIX host Samba is running on, and
+ still obeys all the file permission rules that a Samba
+ administrator can set.</p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>
+ All access to Unix/Linux system file via Samba is controlled at
+ the operating system file access control level. When trying to
+ figure out file access problems it is vitally important to identify
+ the identity of the Windows user as it is presented by Samba at
+ the point of file access. This can best be determined from the
+ Samba log files.
+ </p></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2922986"></a>Viewing File Security on a Samba Share</h3></div></div><div></div></div><p>From an NT4/2000/XP client, single-click with the right
+ mouse button on any file or directory in a Samba mounted
+ drive letter or UNC path. When the menu pops-up, click
+ on the <span class="guilabel">Properties</span> entry at the bottom of
+ the menu. This brings up the file properties dialog
+ box. Click on the tab <span class="guilabel">Security</span> and you
+ will see three buttons, <span class="guibutton">Permissions</span>,
+ <span class="guibutton">Auditing</span>, and <span class="guibutton">Ownership</span>.
+ The <span class="guibutton">Auditing</span> button will cause either
+ an error message <span class="errorname">A requested privilege is not held
+ by the client</span> to appear if the user is not the
+ NT Administrator, or a dialog which is intended to allow an
+ Administrator to add auditing requirements to a file if the
+ user is logged on as the NT Administrator. This dialog is
+ non-functional with a Samba share at this time, as the only
+ useful button, the <span class="guibutton">Add</span> button will not currently
+ allow a list of users to be seen.</p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2923065"></a>Viewing file ownership</h3></div></div><div></div></div><p>Clicking on the <span class="guibutton">Ownership</span> button
+ brings up a dialog box telling you who owns the given file. The
+ owner name will be of the form :</p><p><b class="command">&quot;SERVER\user (Long name)&quot;</b></p><p>Where <i class="replaceable"><tt>SERVER</tt></i> is the NetBIOS name of
+ the Samba server, <i class="replaceable"><tt>user</tt></i> is the user name of
+ the UNIX user who owns the file, and <i class="replaceable"><tt>(Long name)</tt></i>
+ is the descriptive string identifying the user (normally found in the
+ GECOS field of the UNIX password database). Click on the
+ <span class="guibutton">Close </span> button to remove this dialog.</p><p>If the parameter <i class="parameter"><tt>nt acl support</tt></i>
+ is set to <tt class="constant">false</tt> then the file owner will
+ be shown as the NT user <tt class="constant">&quot;Everyone&quot;</tt>.</p><p>The <span class="guibutton">Take Ownership</span> button will not allow
+ you to change the ownership of this file to yourself (clicking on
+ it will display a dialog box complaining that the user you are
+ currently logged onto the NT client cannot be found). The reason
+ for this is that changing the ownership of a file is a privileged
+ operation in UNIX, available only to the <span class="emphasis"><em>root</em></span>
+ user. As clicking on this button causes NT to attempt to change
+ the ownership of a file to the current user logged into the NT
+ client this will not work with Samba at this time.</p><p>There is an NT chown command that will work with Samba
+ and allow a user with Administrator privilege connected
+ to a Samba server as root to change the ownership of
+ files on both a local NTFS filesystem or remote mounted NTFS
+ or Samba drive. This is available as part of the <span class="application">Seclib
+ </span> NT security library written by Jeremy Allison of
+ the Samba Team, available from the main Samba ftp site.</p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2923187"></a>Viewing File or Directory Permissions</h3></div></div><div></div></div><p>The third button is the <span class="guibutton">Permissions</span>
+ button. Clicking on this brings up a dialog box that shows both
+ the permissions and the UNIX owner of the file or directory.
+ The owner is displayed in the form :</p><p><b class="command">&quot;<i class="replaceable"><tt>SERVER</tt></i>\
+ <i class="replaceable"><tt>user</tt></i>
+ <i class="replaceable"><tt>(Long name)</tt></i>&quot;</b></p><p>Where <i class="replaceable"><tt>SERVER</tt></i> is the NetBIOS name of
+ the Samba server, <i class="replaceable"><tt>user</tt></i> is the user name of
+ the UNIX user who owns the file, and <i class="replaceable"><tt>(Long name)</tt></i>
+ is the descriptive string identifying the user (normally found in the
+ GECOS field of the UNIX password database).</p><p>If the parameter <i class="parameter"><tt>nt acl support</tt></i>
+ is set to <tt class="constant">false</tt> then the file owner will
+ be shown as the NT user <tt class="constant">&quot;Everyone&quot;</tt> and the
+ permissions will be shown as NT &quot;Full Control&quot;.</p><p>The permissions field is displayed differently for files
+ and directories, so I'll describe the way file permissions
+ are displayed first.</p><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2923278"></a>File Permissions</h4></div></div><div></div></div><p>The standard UNIX user/group/world triple and
+ the corresponding &quot;read&quot;, &quot;write&quot;, &quot;execute&quot; permissions
+ triples are mapped by Samba into a three element NT ACL
+ with the 'r', 'w', and 'x' bits mapped into the corresponding
+ NT permissions. The UNIX world permissions are mapped into
+ the global NT group <tt class="constant">Everyone</tt>, followed
+ by the list of permissions allowed for UNIX world. The UNIX
+ owner and group permissions are displayed as an NT
+ <span class="guiicon">user</span> icon and an NT <span class="guiicon">local
+ group</span> icon respectively followed by the list
+ of permissions allowed for the UNIX user and group.</p><p>As many UNIX permission sets don't map into common
+ NT names such as <tt class="constant">read</tt>, <tt class="constant">
+ &quot;change&quot;</tt> or <tt class="constant">full control</tt> then
+ usually the permissions will be prefixed by the words <tt class="constant">
+ &quot;Special Access&quot;</tt> in the NT display list.</p><p>But what happens if the file has no permissions allowed
+ for a particular UNIX user group or world component ? In order
+ to allow &quot;no permissions&quot; to be seen and modified then Samba
+ overloads the NT <b class="command">&quot;Take Ownership&quot;</b> ACL attribute
+ (which has no meaning in UNIX) and reports a component with
+ no permissions as having the NT <b class="command">&quot;O&quot;</b> bit set.
+ This was chosen of course to make it look like a zero, meaning
+ zero permissions. More details on the decision behind this will
+ be given below.</p></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2923370"></a>Directory Permissions</h4></div></div><div></div></div><p>Directories on an NT NTFS file system have two
+ different sets of permissions. The first set of permissions
+ is the ACL set on the directory itself, this is usually displayed
+ in the first set of parentheses in the normal <tt class="constant">&quot;RW&quot;</tt>
+ NT style. This first set of permissions is created by Samba in
+ exactly the same way as normal file permissions are, described
+ above, and is displayed in the same way.</p><p>The second set of directory permissions has no real meaning
+ in the UNIX permissions world and represents the <tt class="constant">
+ inherited</tt> permissions that any file created within
+ this directory would inherit.</p><p>Samba synthesises these inherited permissions for NT by
+ returning as an NT ACL the UNIX permission mode that a new file
+ created by Samba on this share would receive.</p></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2923415"></a>Modifying file or directory permissions</h3></div></div><div></div></div><p>Modifying file and directory permissions is as simple
+ as changing the displayed permissions in the dialog box, and
+ clicking the <span class="guibutton">OK</span> button. However, there are
+ limitations that a user needs to be aware of, and also interactions
+ with the standard Samba permission masks and mapping of DOS
+ attributes that need to also be taken into account.</p><p>If the parameter <i class="parameter"><tt>nt acl support</tt></i>
+ is set to <tt class="constant">false</tt> then any attempt to set
+ security permissions will fail with an <span class="errorname">&quot;Access Denied&quot;
+ </span> message.</p><p>The first thing to note is that the <span class="guibutton">&quot;Add&quot;</span>
+ button will not return a list of users in Samba (it will give
+ an error message of <span class="errorname">The remote procedure call failed
+ and did not execute</span>). This means that you can only
+ manipulate the current user/group/world permissions listed in
+ the dialog box. This actually works quite well as these are the
+ only permissions that UNIX actually has.</p><p>If a permission triple (either user, group, or world)
+ is removed from the list of permissions in the NT dialog box,
+ then when the <span class="guibutton">OK</span> button is pressed it will
+ be applied as &quot;no permissions&quot; on the UNIX side. If you then
+ view the permissions again the &quot;no permissions&quot; entry will appear
+ as the NT <b class="command">&quot;O&quot;</b> flag, as described above. This
+ allows you to add permissions back to a file or directory once
+ you have removed them from a triple component.</p><p>As UNIX supports only the &quot;r&quot;, &quot;w&quot; and &quot;x&quot; bits of
+ an NT ACL then if other NT security attributes such as &quot;Delete
+ access&quot; are selected then they will be ignored when applied on
+ the Samba server.</p><p>When setting permissions on a directory the second
+ set of permissions (in the second set of parentheses) is
+ by default applied to all files within that directory. If this
+ is not what you want you must uncheck the <span class="guilabel">Replace
+ permissions on existing files</span> checkbox in the NT
+ dialog before clicking <span class="guibutton">OK</span>.</p><p>If you wish to remove all permissions from a
+ user/group/world component then you may either highlight the
+ component and click the <span class="guibutton">Remove</span> button,
+ or set the component to only have the special <tt class="constant">Take
+ Ownership</tt> permission (displayed as <b class="command">&quot;O&quot;
+ </b>) highlighted.</p></div><div xmlns:ns31="" class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2923567"></a>Interaction with the standard Samba create mask
+ parameters</h3></div></div><div></div></div><ns31:p>There are four parameters
+ to control interaction with the standard Samba create mask parameters.
+ These are :
+
+ </ns31:p><table class="simplelist" border="0" summary="Simple list"><tr><td><i class="parameter"><tt>security mask</tt></i></td></tr><tr><td><i class="parameter"><tt>force security mode</tt></i></td></tr><tr><td><i class="parameter"><tt>directory security mask</tt></i></td></tr><tr><td><i class="parameter"><tt>force directory security mode</tt></i></td></tr></table><ns31:p>
+
+ </ns31:p><p>Once a user clicks <span class="guibutton">OK</span> to apply the
+ permissions Samba maps the given permissions into a user/group/world
+ r/w/x triple set, and then will check the changed permissions for a
+ file against the bits set in the <a href="smb.conf.5.html#SECURITYMASK" target="_top">
+ <i class="parameter"><tt>security mask</tt></i></a> parameter. Any bits that
+ were changed that are not set to '1' in this parameter are left alone
+ in the file permissions.</p><p>Essentially, zero bits in the <i class="parameter"><tt>security mask</tt></i>
+ mask may be treated as a set of bits the user is <span class="emphasis"><em>not</em></span>
+ allowed to change, and one bits are those the user is allowed to change.
+ </p><p>If not set explicitly this parameter is set to the same value as
+ the <a href="smb.conf.5.html#CREATEMASK" target="_top"><i class="parameter"><tt>create mask
+ </tt></i></a> parameter. To allow a user to modify all the
+ user/group/world permissions on a file, set this parameter
+ to 0777.</p><p>Next Samba checks the changed permissions for a file against
+ the bits set in the <a href="smb.conf.5.html#FORCESECURITYMODE" target="_top">
+ <i class="parameter"><tt>force security mode</tt></i></a> parameter. Any bits
+ that were changed that correspond to bits set to '1' in this parameter
+ are forced to be set.</p><p>Essentially, bits set in the <i class="parameter"><tt>force security mode
+ </tt></i> parameter may be treated as a set of bits that, when
+ modifying security on a file, the user has always set to be 'on'.</p><p>If not set explicitly this parameter is set to the same value
+ as the <a href="smb.conf.5.html#FORCECREATEMODE" target="_top"><i class="parameter"><tt>force
+ create mode</tt></i></a> parameter.
+ To allow a user to modify all the user/group/world permissions on a file
+ with no restrictions set this parameter to 000.</p><p>The <i class="parameter"><tt>security mask</tt></i> and <i class="parameter"><tt>force
+ security mode</tt></i> parameters are applied to the change
+ request in that order.</p><p>For a directory Samba will perform the same operations as
+ described above for a file except using the parameter <i class="parameter"><tt>
+ directory security mask</tt></i> instead of <i class="parameter"><tt>security
+ mask</tt></i>, and <i class="parameter"><tt>force directory security mode
+ </tt></i> parameter instead of <i class="parameter"><tt>force security mode
+ </tt></i>.</p><p>The <i class="parameter"><tt>directory security mask</tt></i> parameter
+ by default is set to the same value as the <i class="parameter"><tt>directory mask
+ </tt></i> parameter and the <i class="parameter"><tt>force directory security
+ mode</tt></i> parameter by default is set to the same value as
+ the <i class="parameter"><tt>force directory mode</tt></i> parameter. </p><p>In this way Samba enforces the permission restrictions that
+ an administrator can set on a Samba share, whilst still allowing users
+ to modify the permission bits within that restriction.</p><p>If you want to set up a share that allows users full control
+ in modifying the permission bits on their files and directories and
+ doesn't force any particular bits to be set 'on', then set the following
+ parameters in the <tt class="filename">smb.conf</tt> file in that share specific section :
+ </p><table class="simplelist" border="0" summary="Simple list"><tr><td><i class="parameter"><tt>security mask = 0777</tt></i></td></tr><tr><td><i class="parameter"><tt>force security mode = 0</tt></i></td></tr><tr><td><i class="parameter"><tt>directory security mask = 0777</tt></i></td></tr><tr><td><i class="parameter"><tt>force directory security mode = 0</tt></i></td></tr></table></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2923897"></a>Interaction with the standard Samba file attribute
+ mapping</h3></div></div><div></div></div><p>Samba maps some of the DOS attribute bits (such as &quot;read
+ only&quot;) into the UNIX permissions of a file. This means there can
+ be a conflict between the permission bits set via the security
+ dialog and the permission bits set by the file attribute mapping.
+ </p><p>One way this can show up is if a file has no UNIX read access
+ for the owner it will show up as &quot;read only&quot; in the standard
+ file attributes tabbed dialog. Unfortunately this dialog is
+ the same one that contains the security info in another tab.</p><p>What this can mean is that if the owner changes the permissions
+ to allow themselves read access using the security dialog, clicks
+ <span class="guibutton">OK</span> to get back to the standard attributes tab
+ dialog, and then clicks <span class="guibutton">OK</span> on that dialog, then
+ NT will set the file permissions back to read-only (as that is what
+ the attributes still say in the dialog). This means that after setting
+ permissions and clicking <span class="guibutton">OK</span> to get back to the
+ attributes dialog you should always hit <span class="guibutton">Cancel</span>
+ rather than <span class="guibutton">OK</span> to ensure that your changes
+ are not overridden.</p></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2923972"></a>Common Errors</h2></div></div><div></div></div><p>
+File, Directory and Share access problems are very common on the mailing list. The following
+are examples taken from the mailing list in recent times.
+</p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2923986"></a>Users can not write to a public share</h3></div></div><div></div></div><p>
+ &#8220;<span class="quote">
+ We are facing some troubles with file / directory permissions. I can log on the domain as admin user(root),
+ and theres a public share, on which everyone needs to have permission to create / modify files, but only
+ root can change the file, no one else can. We need to constantly go to server to
+ <b class="userinput"><tt>chgrp -R users *</tt></b> and <b class="userinput"><tt>chown -R nobody *</tt></b> to allow others users to change the file.
+ </span>&#8221;
+ </p><p>
+ There are many ways to solve this problem, here are a few hints:
+ </p><div class="procedure"><p class="title"><b>Procedure 13.3. Example Solution:</b></p><ol type="1"><li><p>
+ Go to the top of the directory that is shared
+ </p></li><li xmlns:ns32=""><ns32:p>
+ Set the ownership to what ever public owner and group you want
+ </ns32:p><pre class="programlisting">
+ find 'directory_name' -type d -exec chown user.group {}\;
+ find 'directory_name' -type d -exec chmod 6775 'directory_name'
+ find 'directory_name' -type f -exec chmod 0775 {} \;
+ find 'directory_name' -type f -exec chown user.group {}\;
+ </pre><ns32:p>
+ </ns32:p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>
+ The above will set the 'sticky bit' on all directories. Read your
+ Unix/Linux man page on what that does. It causes the OS to assign
+ to all files created in the directories the ownership of the
+ directory.
+ </p></div></li><li xmlns:ns33=""><ns33:p>
+
+ Directory is: <i class="replaceable"><tt>/foodbar</tt></i>
+ </ns33:p><pre class="screen">
+ <tt class="prompt">$ </tt><b class="userinput"><tt>chown jack.engr /foodbar</tt></b>
+ </pre><ns33:p>
+ </ns33:p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><ns33:p>
+ </ns33:p><p>This is the same as doing:</p><ns33:p>
+ </ns33:p><pre class="screen">
+ <tt class="prompt">$ </tt><b class="userinput"><tt>chown jack /foodbar</tt></b>
+ <tt class="prompt">$ </tt><b class="userinput"><tt>chgrp engr /foodbar</tt></b>
+ </pre><ns33:p>
+ </ns33:p></div></li><li xmlns:ns34=""><ns34:p>Now do:
+
+ </ns34:p><pre class="screen">
+ <tt class="prompt">$ </tt><b class="userinput"><tt>chmod 6775 /foodbar</tt></b>
+ <tt class="prompt">$ </tt><b class="userinput"><tt>ls -al /foodbar/..</tt></b>
+ </pre><ns34:p>
+
+ </ns34:p><ns34:p>You should see:
+ </ns34:p><pre class="screen">
+ drwsrwsr-x 2 jack engr 48 2003-02-04 09:55 foodbar
+ </pre><ns34:p>
+ </ns34:p></li><li xmlns:ns35=""><ns35:p>Now do:
+ </ns35:p><pre class="screen">
+ <tt class="prompt">$ </tt><b class="userinput"><tt>su - jill</tt></b>
+ <tt class="prompt">$ </tt><b class="userinput"><tt>cd /foodbar</tt></b>
+ <tt class="prompt">$ </tt><b class="userinput"><tt>touch Afile</tt></b>
+ <tt class="prompt">$ </tt><b class="userinput"><tt>ls -al</tt></b>
+ </pre><ns35:p>
+ </ns35:p><ns35:p>
+ You should see that the file <tt class="filename">Afile</tt> created by Jill will have ownership
+ and permissions of Jack, as follows:
+ </ns35:p><pre class="screen">
+ -rw-r--r-- 1 jack engr 0 2003-02-04 09:57 Afile
+ </pre><ns35:p>
+ </ns35:p></li><li xmlns:ns36=""><ns36:p>
+ Now in your <tt class="filename">smb.conf</tt> for the share add:
+ </ns36:p><pre class="programlisting">
+ force create mode = 0775
+ force direcrtory mode = 6775
+ </pre><ns36:p>
+ </ns36:p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>
+ The above are only needed <span class="emphasis"><em>if</em></span> your users are <span class="emphasis"><em>not</em></span> members of the group
+ you have used. ie: Within the OS do not have write permission on the directory.
+ </p></div><ns36:p>
+ An alternative is to set in the <tt class="filename">smb.conf</tt> entry for the share:
+ </ns36:p><pre class="programlisting">
+ force user = jack
+ force group = engr
+ </pre><ns36:p>
+ </ns36:p></li></ol></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2924365"></a>I have set force user and samba still makes <span class="emphasis"><em>root</em></span> the owner of all the files
+ I touch!</h3></div></div><div></div></div><p>
+ When you have a user in 'admin users', samba will always do file operations for
+ this user as <span class="emphasis"><em>root</em></span>, even if <i class="parameter"><tt>force user</tt></i> has been set.
+ </p></div></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="groupmapping.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="optional.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="locking.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 12. Mapping MS Windows and Unix Groups </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 14. File and Record Locking</td></tr></table></div></body></html>