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diff --git a/docs/htmldocs/NT_Security.html b/docs/htmldocs/NT_Security.html deleted file mode 100644 index ab8797563e..0000000000 --- a/docs/htmldocs/NT_Security.html +++ /dev/null @@ -1,783 +0,0 @@ -<HTML -><HEAD -><TITLE ->UNIX Permission Bits and Windows NT Access Control Lists</TITLE -><META -NAME="GENERATOR" -CONTENT="Modular DocBook HTML Stylesheet Version 1.57"></HEAD -><BODY -CLASS="ARTICLE" -BGCOLOR="#FFFFFF" -TEXT="#000000" -LINK="#0000FF" -VLINK="#840084" -ALINK="#0000FF" -><DIV -CLASS="ARTICLE" -><DIV -CLASS="TITLEPAGE" -><H1 -CLASS="TITLE" -><A -NAME="UNIX-PERMISSIONS" ->UNIX Permission Bits and Windows NT Access Control Lists</A -></H1 -><HR></DIV -><DIV -CLASS="SECT1" -><H1 -CLASS="SECT1" -><A -NAME="AEN3" ->Viewing and changing UNIX permissions using the NT - security dialogs</A -></H1 -><P ->New in the Samba 2.0.4 release is the ability for Windows - NT clients to 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 -><P ->In Samba 2.0.4 and above the default value of the - parameter <A -HREF="smb.conf.5.html#NTACLSUPPORT" -TARGET="_top" -><TT -CLASS="PARAMETER" -><I -> nt acl support</I -></TT -></A -> has been changed from - <TT -CLASS="CONSTANT" ->false</TT -> to <TT -CLASS="CONSTANT" ->true</TT ->, so - manipulation of permissions is turned on by default.</P -></DIV -><DIV -CLASS="SECT1" -><HR><H1 -CLASS="SECT1" -><A -NAME="AEN12" ->How to view file security on a Samba share</A -></H1 -><P ->From an NT 4.0 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 <I -CLASS="EMPHASIS" ->Properties</I -> entry at the bottom of - the menu. This brings up the normal file properties dialog - box, but with Samba 2.0.4 this will have a new tab along the top - marked <I -CLASS="EMPHASIS" ->Security</I ->. Click on this tab and you - will see three buttons, <I -CLASS="EMPHASIS" ->Permissions</I ->, - <I -CLASS="EMPHASIS" ->Auditing</I ->, and <I -CLASS="EMPHASIS" ->Ownership</I ->. - The <I -CLASS="EMPHASIS" ->Auditing</I -> 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 <B -CLASS="COMMAND" ->Add</B -> button will not currently - allow a list of users to be seen.</P -></DIV -><DIV -CLASS="SECT1" -><HR><H1 -CLASS="SECT1" -><A -NAME="AEN23" ->Viewing file ownership</A -></H1 -><P ->Clicking on the <B -CLASS="COMMAND" ->"Ownership"</B -> 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" ->"SERVER\user (Long name)"</B -></P -><P ->Where <TT -CLASS="REPLACEABLE" -><I ->SERVER</I -></TT -> is the NetBIOS name of - the Samba server, <TT -CLASS="REPLACEABLE" -><I ->user</I -></TT -> is the user name of - the UNIX user who owns the file, and <TT -CLASS="REPLACEABLE" -><I ->(Long name)</I -></TT -> - is the descriptive string identifying the user (normally found in the - GECOS field of the UNIX password database). Click on the <B -CLASS="COMMAND" ->Close - </B -> button to remove this dialog.</P -><P ->If the parameter <TT -CLASS="PARAMETER" -><I ->nt acl support</I -></TT -> - is set to <TT -CLASS="CONSTANT" ->false</TT -> then the file owner will - be shown as the NT user <B -CLASS="COMMAND" ->"Everyone"</B ->.</P -><P ->The <B -CLASS="COMMAND" ->Take Ownership</B -> 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 <I -CLASS="EMPHASIS" ->root</I -> - 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 2.0.4 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 <I -CLASS="EMPHASIS" ->Seclib - </I -> NT security library written by Jeremy Allison of - the Samba Team, available from the main Samba ftp site.</P -></DIV -><DIV -CLASS="SECT1" -><HR><H1 -CLASS="SECT1" -><A -NAME="AEN43" ->Viewing file or directory permissions</A -></H1 -><P ->The third button is the <B -CLASS="COMMAND" ->"Permissions"</B -> - 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" ->"SERVER\user (Long name)"</B -></P -><P ->Where <TT -CLASS="REPLACEABLE" -><I ->SERVER</I -></TT -> is the NetBIOS name of - the Samba server, <TT -CLASS="REPLACEABLE" -><I ->user</I -></TT -> is the user name of - the UNIX user who owns the file, and <TT -CLASS="REPLACEABLE" -><I ->(Long name)</I -></TT -> - is the descriptive string identifying the user (normally found in the - GECOS field of the UNIX password database).</P -><P ->If the parameter <TT -CLASS="PARAMETER" -><I ->nt acl support</I -></TT -> - is set to <TT -CLASS="CONSTANT" ->false</TT -> then the file owner will - be shown as the NT user <B -CLASS="COMMAND" ->"Everyone"</B -> and the - permissions will be shown as NT "Full Control".</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="SECT2" -><HR><H2 -CLASS="SECT2" -><A -NAME="AEN58" ->File Permissions</A -></H2 -><P ->The standard UNIX user/group/world triple and - the corresponding "read", "write", "execute" 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 <B -CLASS="COMMAND" ->Everyone</B ->, followed - by the list of permissions allowed for UNIX world. The UNIX - owner and group permissions are displayed as an NT - <B -CLASS="COMMAND" ->user</B -> icon and an NT <B -CLASS="COMMAND" ->local - group</B -> 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 <B -CLASS="COMMAND" ->"read"</B ->, <B -CLASS="COMMAND" -> "change"</B -> or <B -CLASS="COMMAND" ->"full control"</B -> then - usually the permissions will be prefixed by the words <B -CLASS="COMMAND" -> "Special Access"</B -> 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 "no permissions" to be seen and modified then Samba - overloads the NT <B -CLASS="COMMAND" ->"Take Ownership"</B -> ACL attribute - (which has no meaning in UNIX) and reports a component with - no permissions as having the NT <B -CLASS="COMMAND" ->"O"</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="SECT2" -><HR><H2 -CLASS="SECT2" -><A -NAME="AEN72" ->Directory Permissions</A -></H2 -><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 <B -CLASS="COMMAND" ->"RW"</B -> - 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 <B -CLASS="COMMAND" -> "inherited"</B -> 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="SECT1" -><HR><H1 -CLASS="SECT1" -><A -NAME="AEN79" ->Modifying file or directory permissions</A -></H1 -><P ->Modifying file and directory permissions is as simple - as changing the displayed permissions in the dialog box, and - clicking the <B -CLASS="COMMAND" ->OK</B -> 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 <TT -CLASS="PARAMETER" -><I ->nt acl support</I -></TT -> - is set to <TT -CLASS="CONSTANT" ->false</TT -> then any attempt to set - security permissions will fail with an <B -CLASS="COMMAND" ->"Access Denied" - </B -> message.</P -><P ->The first thing to note is that the <B -CLASS="COMMAND" ->"Add"</B -> - button will not return a list of users in Samba 2.0.4 (it will give - an error message of <B -CLASS="COMMAND" ->"The remote procedure call failed - and did not execute"</B ->). 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 <B -CLASS="COMMAND" ->"OK"</B -> button is pressed it will - be applied as "no permissions" on the UNIX side. If you then - view the permissions again the "no permissions" entry will appear - as the NT <B -CLASS="COMMAND" ->"O"</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 "r", "w" and "x" bits of - an NT ACL then if other NT security attributes such as "Delete - access" 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 <B -CLASS="COMMAND" ->"Replace - permissions on existing files"</B -> checkbox in the NT - dialog before clicking <B -CLASS="COMMAND" ->"OK"</B ->.</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 <B -CLASS="COMMAND" ->"Remove"</B -> button, - or set the component to only have the special <B -CLASS="COMMAND" ->"Take - Ownership"</B -> permission (displayed as <B -CLASS="COMMAND" ->"O" - </B ->) highlighted.</P -></DIV -><DIV -CLASS="SECT1" -><HR><H1 -CLASS="SECT1" -><A -NAME="AEN101" ->Interaction with the standard Samba create mask - parameters</A -></H1 -><P ->Note that with Samba 2.0.5 there are four new parameters - to control this interaction. These are :</P -><P -><TT -CLASS="PARAMETER" -><I ->security mask</I -></TT -></P -><P -><TT -CLASS="PARAMETER" -><I ->force security mode</I -></TT -></P -><P -><TT -CLASS="PARAMETER" -><I ->directory security mask</I -></TT -></P -><P -><TT -CLASS="PARAMETER" -><I ->force directory security mode</I -></TT -></P -><P ->Once a user clicks <B -CLASS="COMMAND" ->"OK"</B -> 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" -> - <TT -CLASS="PARAMETER" -><I ->security mask</I -></TT -></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 <TT -CLASS="PARAMETER" -><I ->security mask</I -></TT -> - mask may be treated as a set of bits the user is <I -CLASS="EMPHASIS" ->not</I -> - 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" -><TT -CLASS="PARAMETER" -><I ->create mask - </I -></TT -></A -> parameter to provide compatibility with Samba 2.0.4 - where this permission change facility was introduced. 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" -> <TT -CLASS="PARAMETER" -><I ->force security mode</I -></TT -></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 <TT -CLASS="PARAMETER" -><I ->force security mode - </I -></TT -> 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" -><TT -CLASS="PARAMETER" -><I ->force - create mode</I -></TT -></A -> parameter to provide compatibility - with Samba 2.0.4 where the permission change facility was introduced. - 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 <TT -CLASS="PARAMETER" -><I ->security mask</I -></TT -> and <TT -CLASS="PARAMETER" -><I ->force - security mode</I -></TT -> 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 <TT -CLASS="PARAMETER" -><I -> directory security mask</I -></TT -> instead of <TT -CLASS="PARAMETER" -><I ->security - mask</I -></TT ->, and <TT -CLASS="PARAMETER" -><I ->force directory security mode - </I -></TT -> parameter instead of <TT -CLASS="PARAMETER" -><I ->force security mode - </I -></TT ->.</P -><P ->The <TT -CLASS="PARAMETER" -><I ->directory security mask</I -></TT -> parameter - by default is set to the same value as the <TT -CLASS="PARAMETER" -><I ->directory mask - </I -></TT -> parameter and the <TT -CLASS="PARAMETER" -><I ->force directory security - mode</I -></TT -> parameter by default is set to the same value as - the <TT -CLASS="PARAMETER" -><I ->force directory mode</I -></TT -> parameter to provide - compatibility with Samba 2.0.4 where the permission change facility - was introduced.</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 <A -HREF="smb.conf.5.html" -TARGET="_top" -><TT -CLASS="FILENAME" ->smb.conf(5) - </TT -></A -> file in that share specific section :</P -><P -><TT -CLASS="PARAMETER" -><I ->security mask = 0777</I -></TT -></P -><P -><TT -CLASS="PARAMETER" -><I ->force security mode = 0</I -></TT -></P -><P -><TT -CLASS="PARAMETER" -><I ->directory security mask = 0777</I -></TT -></P -><P -><TT -CLASS="PARAMETER" -><I ->force directory security mode = 0</I -></TT -></P -><P ->As described, in Samba 2.0.4 the parameters :</P -><P -><TT -CLASS="PARAMETER" -><I ->create mask</I -></TT -></P -><P -><TT -CLASS="PARAMETER" -><I ->force create mode</I -></TT -></P -><P -><TT -CLASS="PARAMETER" -><I ->directory mask</I -></TT -></P -><P -><TT -CLASS="PARAMETER" -><I ->force directory mode</I -></TT -></P -><P ->were used instead of the parameters discussed here.</P -></DIV -><DIV -CLASS="SECT1" -><HR><H1 -CLASS="SECT1" -><A -NAME="AEN165" ->Interaction with the standard Samba file attribute - mapping</A -></H1 -><P ->Samba maps some of the DOS attribute bits (such as "read - only") 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 "read only" 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 - <B -CLASS="COMMAND" ->"OK"</B -> to get back to the standard attributes tab - dialog, and then clicks <B -CLASS="COMMAND" ->"OK"</B -> 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 <B -CLASS="COMMAND" ->"OK"</B -> to get back to the - attributes dialog you should always hit <B -CLASS="COMMAND" ->"Cancel"</B -> - rather than <B -CLASS="COMMAND" ->"OK"</B -> to ensure that your changes - are not overridden.</P -></DIV -></DIV -></BODY -></HTML ->
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