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-rw-r--r--docs/docbook/projdoc/AccessControls.xml205
1 files changed, 193 insertions, 12 deletions
diff --git a/docs/docbook/projdoc/AccessControls.xml b/docs/docbook/projdoc/AccessControls.xml
index c903af4468..f7445bdb4a 100644
--- a/docs/docbook/projdoc/AccessControls.xml
+++ b/docs/docbook/projdoc/AccessControls.xml
@@ -60,20 +60,61 @@ shrink.
<itemizedlist>
<title>Samba Access Control Facilities</title>
<listitem><para>
- Unix file and directory permissions
- </para></listitem>
+ <emphasis>Unix File and Directory Permissions</emphasis>
+ </para>
+
+ <para>
+ 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 orr
+ 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.
+ </para>
+ </listitem>
<listitem><para>
- Samba Share Definitions
- </para></listitem>
+ <emphasis>Samba Share Definitions</emphasis>
+ </para>
+
+ <para>
+ In configuring share settings and controls in the &smb.conf; 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 <emphasis>best</emphasis> way to achieve this.
+ The basic options and techniques are described herein.
+ </para>
+ </listitem>
<listitem><para>
- Samba Share ACLs
- </para></listitem>
+ <emphasis>Samba Share ACLs</emphasis>
+ </para>
+
+ <para>
+ 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.
+ </para>
+ </listitem>
<listitem><para>
- MS Windows ACLs through Unix POSIX ACLs
- </para></listitem>
+ <emphasis>MS Windows ACLs through Unix POSIX ACLs</emphasis>
+ </para>
+
+ <para>
+ 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.
+ </para>
+ </listitem>
</itemizedlist>
</sect1>
@@ -82,16 +123,156 @@ shrink.
<title>File System Access Controls</title>
<para>
-Explain here how Unix file and permissions work
+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.
</para>
+ <sect2>
+ <title>MS Windows NTFS Comparison with Unix File Systems</title>
+
+ <para>
+ 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.
+ </para>
+
+ <para>
+ 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 &smb.conf; man page.
+ </para>
+
+ <itemizedlist>
+ <title>File System Feature Comparison</title>
+ <listitem>
+ <para><emphasis>Name Space</emphasis></para>
+ <para>
+ 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.
+ </para>
+ <para>
+ What MS Windows calls a Folder, Unix calls a directory,
+ </para>
+ </listitem>
+
+ <listitem>
+ <para><emphasis>Case Sensitivity</emphasis></para>
+ <para>
+ 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.
+ </para>
+ <para>
+ 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.
+ </para>
+ <para>
+ Consider the following, all are unique Unix names but one single MS Windows file name:
+ <programlisting>
+ MYFILE.TXT
+ MyFile.txt
+ myfile.txt
+ </programlisting>
+ 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.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para><emphasis>Directory Separators</emphasis></para>
+ <para>
+ 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.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para><emphasis>Drive Identification</emphasis></para>
+ <para>
+ MS Windows products support a notion of drive letters, like <command>C:</command> to represent
+ disk partitions. Unix has NO concept if separate identifiers for file partitions since each
+ such file system is <filename>mounted</filename> 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
+ <command>C:\</command>.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para><emphasis>File Naming Conventions</emphasis></para>
+ <para>
+ 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.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para><emphasis>Links and Short-Cuts</emphasis></para>
+ <para>
+ MS Windows make use of "links and Short-Cuts" 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.
+ </para>
+ <para>
+ 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.
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ 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.
+ </para>
+
+ </sect2>
+
+ <sect2>
+ <title>Managing Directories</title>
+
+ <para>
+ There are three basic operations for managing directories, <command>create, delete, rename</command>.
+ <programlisting>
+ Action MS Windows Command Unix Command
+ ------ ------------------ ------------
+ create md folder mkdir folder
+ delete rd folder rmdir folder
+ rename rename oldname newname mv oldname newname
+ </programlisting>
+ </para>
+
+ </sect2>
+
+ <sect2>
+ <title>File and Directory Access Control</title>
+
+ <para>
+ Explain the anatomy of a directory listing, permissions and what they mean.
+ </para>
+
+ </sect2>
+
</sect1>
<sect1>
<title>Share Definition Access Controls</title>
<para>
-Explain here about the smb.conf [share] parameters
+Explain here about the smb.conf [share] Access Control parameters, Mode and Mask parameters, force user/group, valid/invalid users, etc.
</para>
</sect1>
@@ -241,7 +422,7 @@ Explain here about the smb.conf [share] parameters
on the <emphasis>Properties</emphasis> entry at the bottom of
the menu. This brings up the file properties dialog
box. Click on the tab <emphasis>Security</emphasis> and you
- will see three buttons, <emphasis>Permissions</emphasis>,
+ will see three buttons, <emphasis>Permissions</emphasis>,
<emphasis>Auditing</emphasis>, and <emphasis>Ownership</emphasis>.
The <emphasis>Auditing</emphasis> button will cause either
an error message <errorname>A requested privilege is not held
@@ -539,7 +720,7 @@ Explain here about the smb.conf [share] parameters
<title>Common Errors</title>
<para>
-Stuff here
+Stuff from mailing lists here
</para>
</sect1>