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1 <html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Chapter 11. Account Information Databases</title><link rel="stylesheet" href="../samba.css" type="text/css"><meta name="generator" content="DocBook XSL Stylesheets V1.74.0"><link rel="home" href="index.html" title="The Official Samba 3.5.x HOWTO and Reference Guide"><link rel="up" href="optional.html" title="Part III. Advanced Configuration"><link rel="prev" href="NetworkBrowsing.html" title="Chapter 10. Network Browsing"><link rel="next" href="groupmapping.html" title="Chapter 12. Group Mapping: MS Windows and UNIX"></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 11. Account Information Databases</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="NetworkBrowsing.html">Prev</a> </td><th width="60%" align="center">Part III. Advanced Configuration</th><td width="20%" align="right"> <a accesskey="n" href="groupmapping.html">Next</a></td></tr></table><hr></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="passdb"></a>Chapter 11. Account Information Databases</h2></div><div><div class="author"><h3 class="author"><span class="firstname">Jelmer</span> <span class="othername">R.</span> <span class="orgname">The Samba Team</span> <span class="surname">Vernooij</span></h3><div class="affiliation"><span class="orgname">The Samba Team<br></span><div class="address"><p><code class="email"><<a class="email" href="mailto:jelmer@samba.org">jelmer@samba.org</a>></code></p></div></div></div></div><div><div class="author"><h3 class="author"><span class="firstname">John</span> <span class="othername">H.</span> <span class="orgname">Samba Team</span> <span class="surname">Terpstra</span></h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><code class="email"><<a class="email" href="mailto:jht@samba.org">jht@samba.org</a>></code></p></div></div></div></div><div><div class="author"><h3 class="author"><span class="firstname">Gerald</span> <span class="othername">(Jerry)</span> <span class="orgname">Samba Team</span> <span class="surname">Carter</span></h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><code class="email"><<a class="email" href="mailto:jerry@samba.org">jerry@samba.org</a>></code></p></div></div></div></div><div><div class="author"><h3 class="author"><span class="firstname">Jeremy</span> <span class="orgname">Samba Team</span> <span class="surname">Allison</span></h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><code class="email"><<a class="email" href="mailto:jra@samba.org">jra@samba.org</a>></code></p></div></div></div></div><div><div class="author"><h3 class="author"><span class="firstname">Guenther</span> <span class="orgname">Samba Team</span> <span class="surname">Deschner</span></h3><span class="contrib">LDAP updates</span> <div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><code class="email"><<a class="email" href="mailto:gd@samba.org">gd@samba.org</a>></code></p></div></div></div></div><div><div class="author"><h3 class="author"><span class="firstname">Olivier (lem)</span> <span class="orgname">IDEALX</span> <span class="surname">Lemaire</span></h3><div class="affiliation"><span class="orgname">IDEALX<br></span><div class="address"><p><code class="email"><<a class="email" href="mailto:olem@IDEALX.org">olem@IDEALX.org</a>></code></p></div></div></div></div><div><p class="pubdate">May 24, 2003</p></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="sect1"><a href="passdb.html#id2587269">Features and Benefits</a></span></dt><dd><dl><dt><span class="sect2"><a href="passdb.html#id2587306">Backward Compatibility Account Storage Systems</a></span></dt><dt><span class="sect2"><a href="passdb.html#id2587489">New Account Storage Systems</a></span></dt></dl></dd><dt><span class="sect1"><a href="passdb.html#passdbtech">Technical Information</a></span></dt><dd><dl><dt><span class="sect2"><a href="passdb.html#id2588057">Important Notes About Security</a></span></dt><dt><span class="sect2"><a href="passdb.html#id2588577">Mapping User Identifiers between MS Windows and UNIX</a></span></dt><dt><span class="sect2"><a href="passdb.html#idmapbackend">Mapping Common UIDs/GIDs on Distributed Machines</a></span></dt><dt><span class="sect2"><a href="passdb.html#id2589125">Comments Regarding LDAP</a></span></dt><dt><span class="sect2"><a href="passdb.html#id2589538">LDAP Directories and Windows Computer Accounts</a></span></dt></dl></dd><dt><span class="sect1"><a href="passdb.html#acctmgmttools">Account Management Tools</a></span></dt><dd><dl><dt><span class="sect2"><a href="passdb.html#id2589979">The smbpasswd Tool</a></span></dt><dt><span class="sect2"><a href="passdb.html#pdbeditthing">The pdbedit Tool</a></span></dt></dl></dd><dt><span class="sect1"><a href="passdb.html#id2592519">Password Backends</a></span></dt><dd><dl><dt><span class="sect2"><a href="passdb.html#id2592573">Plaintext</a></span></dt><dt><span class="sect2"><a href="passdb.html#id2592649">smbpasswd: Encrypted Password Database</a></span></dt><dt><span class="sect2"><a href="passdb.html#id2592915">tdbsam</a></span></dt><dt><span class="sect2"><a href="passdb.html#id2593073">ldapsam</a></span></dt></dl></dd><dt><span class="sect1"><a href="passdb.html#id2595597">Common Errors</a></span></dt><dd><dl><dt><span class="sect2"><a href="passdb.html#id2595603">Users Cannot Logon</a></span></dt><dt><span class="sect2"><a href="passdb.html#id2595641">Configuration of auth methods</a></span></dt></dl></dd></dl></div><p>
6 Early releases of Samba-3 implemented new capability to work concurrently with multiple account backends. This
7 capability was removed beginning with release of Samba 3.0.23. Commencing with Samba 3.0.23 it is possible to
8 work with only one specified passwd backend.
9 </p><p>
16 The three passdb backends that are fully maintained (actively supported) by the Samba Team are:
17 <code class="literal">smbpasswd</code> (being obsoleted), <code class="literal">tdbsam</code> (a tdb-based binary file format),
18 and <code class="literal">ldapsam</code> (LDAP directory). Of these, only the <code class="literal">ldapsam</code> backend
19 stores both POSIX (UNIX) and Samba user and group account information in a single repository. The
20 <code class="literal">smbpasswd</code> and <code class="literal">tdbsam</code> backends store only Samba user accounts.
21 </p><p>
22 In a strict sense, there are three supported account storage and access systems. One of these is considered
23 obsolete (smbpasswd). It is recommended to use the <code class="literal">tdbsam</code> method for all simple systems. Use
25 </p><p>
33 In a strict and literal sense, the passdb backends are account storage mechanisms (or methods) alone. The choice
34 of terminology can be misleading, however we are stuck with this choice of wording. This chapter documents the
35 nature of the account storage system with a focus on user and trust accounts. Trust accounts have two forms,
36 machine trust accounts (computer accounts) and interdomain trust accounts. These are all treated as user-like
37 entities.
38 </p><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2587269"></a>Features and Benefits</h2></div></div></div><p>
40 as follows:
44 </p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2587306"></a>Backward Compatibility Account Storage Systems</h3></div></div></div><div class="variablelist"><dl><dt><span class="term">Plaintext</span></dt><dd><p>
50 This isn't really a backend at all, but is listed here for simplicity. Samba can be configured to pass
51 plaintext authentication requests to the traditional UNIX/Linux <code class="filename">/etc/passwd</code> and
52 <code class="filename">/etc/shadow</code>-style subsystems. On systems that have Pluggable Authentication Modules
53 (PAM) support, all PAM modules are supported. The behavior is just as it was with Samba-2.2.x, and the
54 protocol limitations imposed by MS Windows clients apply likewise. Please refer to <a class="link" href="passdb.html#passdbtech" title="Technical Information">Technical Information</a>, for more information regarding the limitations of plaintext
55 password usage.
62 file that maintains a plain ASCII (text) layout that includes the MS Windows
63 LanMan and NT-encrypted passwords as well as a field that stores some
64 account information. This form of password backend does not store any of
65 the MS Windows NT/200x SAM (Security Account Manager) information required to
66 provide the extended controls that are needed for more comprehensive
67 interoperation with MS Windows NT4/200x servers.
68 </p><p>
69 This backend should be used only for backward compatibility with older
70 versions of Samba. It may be deprecated in future releases.
75 There is a password backend option that allows continued operation with
76 an existing OpenLDAP backend that uses the Samba-2.2.x LDAP schema extension.
77 This option is provided primarily as a migration tool, although there is
78 no reason to force migration at this time. This tool will eventually
79 be deprecated.
80 </p></dd></dl></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2587489"></a>New Account Storage Systems</h3></div></div></div><p>
81 Samba-3 introduces a number of new password backend capabilities.
88 This backend provides a rich database backend for local servers. This
89 backend is not suitable for multiple domain controllers (i.e., PDC + one
90 or more BDC) installations.
91 </p><p>
98 The <span class="emphasis"><em>tdbsam</em></span> password backend stores the old <span class="emphasis"><em>
100 SAM information into a binary format TDB (trivial database) file.
101 The inclusion of the extended information makes it possible for Samba-3
102 to implement the same account and system access controls that are possible
103 with MS Windows NT4/200x-based systems.
104 </p><p>
109 response to user requests to allow simple site operation without the overhead
110 of the complexities of running OpenLDAP. It is recommended to use this only
111 for sites that have fewer than 250 users. For larger sites or implementations,
112 the use of OpenLDAP or of Active Directory integration is strongly recommended.
116 This provides a rich directory backend for distributed account installation.
117 </p><p>
123 Samba-3 has a new and extended LDAP implementation that requires configuration
124 of OpenLDAP with a new format Samba schema. The new format schema file is
125 included in the <code class="filename">examples/LDAP</code> directory of the Samba distribution.
126 </p><p>
132 The new LDAP implementation significantly expands the control abilities that
133 were possible with prior versions of Samba. It is now possible to specify
134 “<span class="quote">per-user</span>” profile settings, home directories, account access controls, and
135 much more. Corporate sites will see that the Samba Team has listened to their
136 requests both for capability and greater scalability.
137 </p></dd></dl></div></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="passdbtech"></a>Technical Information</h2></div></div></div><p>
140 Old Windows clients send plaintext passwords over the wire. Samba can check these
141 passwords by encrypting them and comparing them to the hash stored in the UNIX user database.
142 </p><p>
147 Newer Windows clients send encrypted passwords (LanMan and NT hashes) instead of plaintext passwords over
148 the wire. The newest clients will send only encrypted passwords and refuse to send plaintext passwords unless
149 their registry is tweaked.
150 </p><p>
153 Many people ask why Samba cannot simply use the UNIX password database. Windows requires
154 passwords that are encrypted in its own format. The UNIX passwords can't be converted to
155 Windows-style encrypted passwords. Because of that, you can't use the standard UNIX user
156 database, and you have to store the LanMan and NT hashes somewhere else.
157 </p><p>
162 In addition to differently encrypted passwords, Windows also stores certain data for each
163 user that is not stored in a UNIX user database: for example, workstations the user may logon from,
164 the location where the user's profile is stored, and so on. Samba retrieves and stores this
165 information using a <a class="link" href="smb.conf.5.html#PASSDBBACKEND" target="_top">passdb backend</a>. Commonly available backends are LDAP,
166 tdbsam, and plain text file. For more information, see the man page for <code class="filename">smb.conf</code> regarding the
167 <a class="link" href="smb.conf.5.html#PASSDBBACKEND" target="_top">passdb backend</a> parameter.
168 </p><div class="figure"><a name="idmap-sid2uid"></a><p class="title"><b>Figure 11.1. IDMAP: Resolution of SIDs to UIDs.</b></p><div class="figure-contents"><div class="mediaobject"><img src="images/idmap-sid2uid.png" width="216" alt="IDMAP: Resolution of SIDs to UIDs."></div></div></div><br class="figure-break"><p>
172 The resolution of SIDs to UIDs is fundamental to correct operation of Samba. In both cases shown, if winbindd
173 is not running or cannot be contacted, then only local SID/UID resolution is possible. See <a class="link" href="passdb.html#idmap-sid2uid" title="Figure 11.1. IDMAP: Resolution of SIDs to UIDs.">resolution of SIDs to UIDs</a> and <a class="link" href="passdb.html#idmap-uid2sid" title="Figure 11.2. IDMAP: Resolution of UIDs to SIDs.">resolution of UIDs
174 to SIDs</a> diagrams.
175 </p><div class="figure"><a name="idmap-uid2sid"></a><p class="title"><b>Figure 11.2. IDMAP: Resolution of UIDs to SIDs.</b></p><div class="figure-contents"><div class="mediaobject"><img src="images/idmap-uid2sid.png" width="270" alt="IDMAP: Resolution of UIDs to SIDs."></div></div></div><br class="figure-break"><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2588057"></a>Important Notes About Security</h3></div></div></div><p>
181 The UNIX and SMB password encryption techniques seem similar on the surface. This
182 similarity is, however, only skin deep. The UNIX scheme typically sends clear-text
183 passwords over the network when logging in. This is bad. The SMB encryption scheme
184 never sends the clear-text password over the network, but it does store the 16-byte
185 hashed values on disk. This is also bad. Why? Because the 16 byte hashed values
186 are a “<span class="quote">password equivalent.</span>” You cannot derive the user's password from them, but
187 they could potentially be used in a modified client to gain access to a server.
188 This would require considerable technical knowledge on behalf of the attacker but
189 is perfectly possible. You should therefore treat the data stored in whatever passdb
190 backend you use (smbpasswd file, LDAP) as though it contained the clear-text
191 passwords of all your users. Its contents must be kept secret, and the file should
192 be protected accordingly.
193 </p><p>
197 Ideally, we would like a password scheme that involves neither plaintext passwords
198 on the network nor plaintext passwords on disk. Unfortunately, this is not available because Samba is stuck with
199 having to be compatible with other SMB systems (Windows NT, Windows for Workgroups, Windows 9x/Me).
200 </p><p>
204 are disabled from being sent over the wire. This mandates either the use of encrypted
205 password support or editing the Windows NT registry to re-enable plaintext passwords.
206 </p><p>
209 The following versions of Microsoft Windows do not support full domain security protocols,
210 although they may log onto a domain environment:
211 </p><div class="itemizedlist"><ul type="disc"><li><p>MS DOS Network client 3.0 with the basic network redirector installed.</p></li><li><p>Windows 95 with the network redirector update installed.</p></li><li><p>Windows 98 [Second Edition].</p></li><li><p>Windows Me.</p></li></ul></div><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>
215 MS Windows XP Home does not have facilities to become a domain member, and it cannot participate in domain logons.
216 </p></div><p>
217 The following versions of MS Windows fully support domain security protocols.
218 </p><div class="itemizedlist"><ul type="disc"><li><p>Windows NT 3.5x.</p></li><li><p>Windows NT 4.0.</p></li><li><p>Windows 2000 Professional.</p></li><li><p>Windows 200x Server/Advanced Server.</p></li><li><p>Windows XP Professional.</p></li></ul></div><p>
225 All current releases of Microsoft SMB/CIFS clients support authentication via the
226 SMB challenge/response mechanism described here. Enabling clear-text authentication
227 does not disable the ability of the client to participate in encrypted authentication.
228 Instead, it allows the client to negotiate either plaintext or encrypted password
229 handling.
230 </p><p>
236 MS Windows clients will cache the encrypted password alone. Where plaintext passwords
237 are re-enabled through the appropriate registry change, the plaintext password is never
238 cached. This means that in the event that a network connections should become disconnected
239 (broken), only the cached (encrypted) password will be sent to the resource server to
240 effect an auto-reconnect. If the resource server does not support encrypted passwords, the
241 auto-reconnect will fail. Use of encrypted passwords is strongly advised.
242 </p><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2588373"></a>Advantages of Encrypted Passwords</h4></div></div></div><div class="itemizedlist"><ul type="disc"><li><p>
246 Plaintext passwords are not passed across the network. Someone using a network sniffer
247 cannot just record passwords going to the SMB server.
248 </p></li><li><p>
252 Plaintext passwords are not stored anywhere in memory or on disk.
253 </p></li><li><p>
258 Windows NT does not like talking to a server that does not support encrypted passwords. It will refuse to
259 browse the server if the server is also in user-level security mode. It will insist on prompting the user for
260 the password on each connection, which is very annoying. The only thing you can do to stop this is to use SMB
261 encryption.
262 </p></li><li><p>
265 Encrypted password support allows automatic share (resource) reconnects.
266 </p></li><li><p>
269 Encrypted passwords are essential for PDC/BDC operation.
270 </p></li></ul></div></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2588513"></a>Advantages of Non-Encrypted Passwords</h4></div></div></div><div class="itemizedlist"><ul type="disc"><li><p>
272 Plaintext passwords are not kept on disk and are not cached in memory.
273 </p></li><li><p>
276 Plaintext passwords use the same password file as other UNIX services, such as Login and FTP.
277 </p></li><li><p>
280 Use of other services (such as Telnet and FTP) that send plaintext passwords over
281 the network makes sending them for SMB not such a big deal.
282 </p></li></ul></div></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2588577"></a>Mapping User Identifiers between MS Windows and UNIX</h3></div></div></div><p>
286 Every operation in UNIX/Linux requires a user identifier (UID), just as in
287 MS Windows NT4/200x this requires a security identifier (SID). Samba provides
288 two means for mapping an MS Windows user to a UNIX/Linux UID.
289 </p><p>
295 First, all Samba SAM database accounts require a UNIX/Linux UID that the account will map to. As users are
296 added to the account information database, Samba will call the <a class="link" href="smb.conf.5.html#ADDUSERSCRIPT" target="_top">add user script</a>
297 interface to add the account to the Samba host OS. In essence all accounts in the local SAM require a local
298 user account.
299 </p><p>
307 The second way to map Windows SID to UNIX UID is via the <span class="emphasis"><em>idmap uid</em></span> and
308 <span class="emphasis"><em>idmap gid</em></span> parameters in <code class="filename">smb.conf</code>. Please refer to the man page for information about
309 these parameters. These parameters are essential when mapping users from a remote (non-member Windows client
310 or a member of a foreign domain) SAM server.
311 </p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="idmapbackend"></a>Mapping Common UIDs/GIDs on Distributed Machines</h3></div></div></div><p>
318 Samba-3 has a special facility that makes it possible to maintain identical UIDs and GIDs
319 on all servers in a distributed network. A distributed network is one where there exists
320 a PDC, one or more BDCs, and/or one or more domain member servers. Why is this important?
321 This is important if files are being shared over more than one protocol (e.g., NFS) and where
322 users are copying files across UNIX/Linux systems using tools such as <code class="literal">rsync</code>.
323 </p><p>
332 The special facility is enabled using a parameter called <em class="parameter"><code>idmap backend</code></em>.
333 The default setting for this parameter is an empty string. Technically it is possible to use
334 an LDAP-based idmap backend for UIDs and GIDs, but it makes most sense when this is done for
335 network configurations that also use LDAP for the SAM backend.
336 <a class="link" href="passdb.html#idmapbackendexample" title="Example 11.1. Example Configuration with the LDAP idmap Backend">Example Configuration with the LDAP idmap Backend</a>
337 shows that configuration.
338 </p><a class="indexterm" name="id2588880"></a><div class="example"><a name="idmapbackendexample"></a><p class="title"><b>Example 11.1. Example Configuration with the LDAP idmap Backend</b></p><div class="example-contents"><table class="simplelist" border="0" summary="Simple list"><tr><td> </td></tr><tr><td><em class="parameter"><code>[global]</code></em></td></tr><tr><td><a class="indexterm" name="id2588913"></a><em class="parameter"><code>idmap backend = ldap:ldap://ldap-server.quenya.org:636</code></em></td></tr><tr><td># Alternatively, this could be specified as:</td></tr><tr><td><a class="indexterm" name="id2588929"></a><em class="parameter"><code>idmap backend = ldap:ldaps://ldap-server.quenya.org</code></em></td></tr></table></div></div><br class="example-break"><p>
341 A network administrator who wants to make significant use of LDAP backends will sooner or later be
342 exposed to the excellent work done by PADL Software. PADL <a class="ulink" href="http://www.padl.com" target="_top">http://www.padl.com</a> have
343 produced and released to open source an array of tools that might be of interest. These tools include:
353 <span class="emphasis"><em>nss_ldap:</em></span> An LDAP name service switch (NSS) module to provide native
354 name service support for AIX, Linux, Solaris, and other operating systems. This tool
355 can be used for centralized storage and retrieval of UIDs and GIDs.
356 </p></li><li><p>
361 <span class="emphasis"><em>pam_ldap:</em></span> A PAM module that provides LDAP integration for UNIX/Linux
362 system access authentication.
363 </p></li><li><p>
368 <span class="emphasis"><em>idmap_ad:</em></span> An IDMAP backend that supports the Microsoft Services for
369 UNIX RFC 2307 schema available from the PADL Web
370 <a class="ulink" href="http://www.padl.com/download/xad_oss_plugins.tar.gz" target="_top">site</a>.
371 </p></li></ul></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2589125"></a>Comments Regarding LDAP</h3></div></div></div><p>
376 There is much excitement and interest in LDAP directories in the information technology world
377 today. The LDAP architecture was designed to be highly scalable. It was also designed for
378 use across a huge number of potential areas of application encompassing a wide range of operating
379 systems and platforms. LDAP technologies are at the heart of the current generations of Federated
380 Identity Management (FIM) solutions that can underlie a corporate Single Sign-On (SSO) environment.
381 </p><p>
386 LDAP implementations have been built across a wide variety of platforms. It lies at the core of Microsoft
387 Windows Active Directory services (ADS), Novell's eDirectory, as well as many others. Implementation of the
388 directory services LDAP involves interaction with legacy as well as new generation applications, all of which
389 depend on some form of authentication services.
390 </p><p>
405 UNIX services can utilize LDAP directory information for authentication and access controls
406 through intermediate tools and utilities. The total environment that consists of the LDAP directory
407 and the middle-ware tools and utilities makes it possible for all user access to the UNIX platform
408 to be managed from a central environment and yet distributed to wherever the point of need may
409 be physically located. Applications that benefit from this infrastructure include: UNIX login
410 shells, mail and messaging systems, quota controls, printing systems, DNS servers, DHCP servers,
411 and also Samba.
412 </p><p>
419 Many sites are installing LDAP for the first time in order to provide a scalable passdb backend
420 for Samba. Others are faced with the need to adapt an existing LDAP directory to new uses such
421 as for the Samba SAM backend. Whatever your particular need and attraction to Samba may be,
422 decisions made in respect of the design of the LDAP directory structure and its implementation
423 are of a durable nature for the site. These have far-reaching implications that affect long-term
424 information systems management costs.
425 </p><p>
428 Do not rush into an LDAP deployment. Take the time to understand how the design of the Directory
429 Information Tree (DIT) may impact current and future site needs, as well as the ability to meet
430 them. The way that Samba SAM information should be stored within the DIT varies from site to site
431 and with each implementation new experience is gained. It is well understood by LDAP veterans that
432 first implementations create awakening, second implementations of LDAP create fear, and
433 third-generation deployments bring peace and tranquility.
434 </p><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2589401"></a>Caution Regarding LDAP and Samba</h4></div></div></div><p>
442 Samba requires UNIX POSIX identity information as well as a place to store information that is
443 specific to Samba and the Windows networking environment. The most used information that must
444 be dealt with includes: user accounts, group accounts, machine trust accounts, interdomain
445 trust accounts, and intermediate information specific to Samba internals.
446 </p><p>
450 The example deployment guidelines in this book, as well as other books and HOWTO documents
451 available from the internet may not fit with established directory designs and implementations.
452 The existing DIT may not be able to accommodate the simple information layout proposed in common
453 sources. Additionally, you may find that the common scripts and tools that are used to provision
454 the LDAP directory for use with Samba may not suit your needs.
455 </p><p>
457 It is not uncommon, for sites that have existing LDAP DITs to find necessity to generate a
458 set of site-specific scripts and utilities to make it possible to deploy Samba within the
459 scope of site operations. The way that user and group accounts are distributed throughout
460 the DIT may make this a challenging matter. The solution will, of course, be rewarding, but
461 the journey to it may be challenging. Take time to understand site needs and do not rush
462 into deployment.
463 </p><p>
466 Above all, do not blindly use scripts and tools that are not suitable for your site. Check
467 and validate all scripts before you execute them to make sure that the existing infrastructure
468 will not be damaged by inadvertent use of an inappropriate tool.
469 </p></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2589538"></a>LDAP Directories and Windows Computer Accounts</h3></div></div></div><p>
473 Samba doesn't provide a turnkey solution to LDAP. It is best to deal with the design and
474 configuration of an LDAP directory prior to integration with Samba. A working knowledge
475 of LDAP makes Samba integration easy, and the lack of a working knowledge of LDAP can make
476 it a frustrating experience.
477 </p><p>
481 Computer (machine) accounts can be placed wherever you like in an LDAP directory subject
482 to some constraints that are described in this chapter.
483 </p><p>
491 The POSIX and sambaSamAccount components of computer (machine) accounts are both used by Samba.
492 Thus, machine accounts are treated inside Samba in the same way that Windows NT4/200X treats
493 them. A user account and a machine account are indistinguishable from each other, except that
494 the machine account ends in a $ character, as do trust accounts.
495 </p><p>
501 The need for Windows user, group, machine, trust, and other accounts to be tied to a valid UNIX
502 UID is a design decision that was made a long way back in the history of Samba development. It
503 is unlikely that this decision will be reversed or changed during the remaining life of the
504 Samba-3.x series.
505 </p><p>
509 The resolution of a UID from the Windows SID is achieved within Samba through a mechanism that
510 must refer back to the host operating system on which Samba is running. The NSS is the preferred
511 mechanism that shields applications (like Samba) from the need to know everything about every
512 host OS it runs on.
513 </p><p>
521 Samba asks the host OS to provide a UID via the “<span class="quote">passwd</span>”, “<span class="quote">shadow</span>”,
522 and “<span class="quote">group</span>” facilities in the NSS control (configuration) file. The best tool
523 for achieving this is left up to the UNIX administrator to determine. It is not imposed by
524 Samba. Samba provides winbindd with its support libraries as one method. It is
525 possible to do this via LDAP, and for that Samba provides the appropriate hooks so that
526 all account entities can be located in an LDAP directory.
527 </p><p>
533 For many the weapon of choice is to use the PADL nss_ldap utility. This utility must
534 be configured so that computer accounts can be resolved to a POSIX/UNIX account UID. That
535 is fundamentally an LDAP design question. The information provided on the Samba list and
536 in the documentation is directed at providing working examples only. The design
537 of an LDAP directory is a complex subject that is beyond the scope of this documentation.
538 </p></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="acctmgmttools"></a>Account Management Tools</h2></div></div></div><p>
542 Samba provides two tools for management of user and machine accounts:
544 </p><p>
549 Samba user account information. The policy management capability is used to administer
550 domain default settings for password aging and management controls to handle failed login
551 attempts.
552 </p><p>
557 Some people are confused when reference is made to <code class="literal">smbpasswd</code> because the
558 name refers to a storage mechanism for SambaSAMAccount information, but it is also the name
559 of a utility tool. That tool is destined to eventually be replaced by new functionality that
560 is being added to the <code class="literal">net</code> toolset (see <a class="link" href="NetCommand.html" title="Chapter 13. Remote and Local Management: The Net Command">the Net Command</a>).
561 </p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2589979"></a>The <code class="literal">smbpasswd</code> Tool</h3></div></div></div><p>
567 The <code class="literal">smbpasswd</code> utility is similar to the <code class="literal">passwd</code>
569 fields in the passdb backend. This utility operates independently of the actual
570 account and password storage methods used (as specified by the <em class="parameter"><code>passdb
572 </p><p>
576 local smbd to change the user's password on its behalf. This has enormous benefits.
577 </p><p>
581 servers (this only works when the request is sent to the NT PDC if changing an NT
582 domain user's password).
583 </p><p>
587 </p><div class="itemizedlist"><ul type="disc"><li><p><span class="emphasis"><em>add</em></span> user or machine accounts.</p></li><li><p><span class="emphasis"><em>delete</em></span> user or machine accounts.</p></li><li><p><span class="emphasis"><em>enable</em></span> user or machine accounts.</p></li><li><p><span class="emphasis"><em>disable</em></span> user or machine accounts.</p></li><li><p><span class="emphasis"><em>set to NULL</em></span> user passwords.</p></li><li><p><span class="emphasis"><em>manage</em></span> interdomain trust accounts.</p></li></ul></div><p>
588 To run smbpasswd as a normal user, just type:
589 </p><p>
592 <code class="prompt">Old SMB password: </code><strong class="userinput"><code><em class="replaceable"><code>secret</code></em></code></strong>
593 </pre><p>
594 For <em class="replaceable"><code>secret</code></em>, type the old value here or press return if
595 there is no old password.
597 <code class="prompt">New SMB Password: </code><strong class="userinput"><code><em class="replaceable"><code>new secret</code></em></code></strong>
598 <code class="prompt">Repeat New SMB Password: </code><strong class="userinput"><code><em class="replaceable"><code>new secret</code></em></code></strong>
599 </pre><p>
600 </p><p>
601 If the old value does not match the current value stored for that user, or the two
602 new values do not match each other, then the password will not be changed.
603 </p><p>
605 When invoked by an ordinary user, the command will allow only the user to change his or her own
606 SMB password.
607 </p><p>
610 When run by root, <code class="literal">smbpasswd</code> may take an optional argument specifying
611 the username whose SMB password you wish to change. When run as root, <code class="literal">smbpasswd</code>
612 does not prompt for or check the old password value, thus allowing root to set passwords
613 for users who have forgotten their passwords.
614 </p><p>
620 users who use the <code class="literal">passwd</code> or <code class="literal">yppasswd</code> commands.
621 While designed for administrative use, this tool provides essential user-level
622 password change capabilities.
623 </p><p>
626 definitive reference).
627 </p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="pdbeditthing"></a>The <code class="literal">pdbedit</code> Tool</h3></div></div></div><p>
633 manage the passdb backend, as well as domain-wide account policy settings. <code class="literal">pdbedit</code>
634 can be used to:
635 </p><div class="itemizedlist"><ul type="disc"><li><p>add, remove, or modify user accounts.</p></li><li><p>list user accounts.</p></li><li><p>migrate user accounts.</p></li><li><p>migrate group accounts.</p></li><li><p>manage account policies.</p></li><li><p>manage domain access policy settings.</p></li></ul></div><p>
637 Under the terms of the Sarbanes-Oxley Act of 2002, American businesses and organizations are mandated to
638 implement a series of <code class="literal">internal controls</code> and procedures to communicate, store,
639 and protect financial data. The Sarbanes-Oxley Act has far reaching implications in respect of:
640 </p><div class="orderedlist"><ol type="1"><li><p>Who has access to information systems that store financial data.</p></li><li><p>How personal and financial information is treated among employees and business
641 partners.</p></li><li><p>How security vulnerabilities are managed.</p></li><li><p>Security and patch level maintenance for all information systems.</p></li><li><p>How information systems changes are documented and tracked.</p></li><li><p>How information access controls are implemented and managed.</p></li><li><p>Auditability of all information systems in respect of change and security.</p></li><li><p>Disciplinary procedures and controls to ensure privacy.</p></li></ol></div><p>
644 In short, the Sarbanes-Oxley Act of 2002 is an instrument that enforces accountability in respect of
645 business related information systems so as to ensure the compliance of all information systems that
646 are used to store personal information and particularly for financial records processing. Similar
647 accountabilities are being demanded around the world.
648 </p><p>
654 The need to be familiar with the Samba tools and facilities that permit information systems operation
655 in compliance with government laws and regulations is clear to all. The <code class="literal">pdbedit</code> is
656 currently the only Samba tool that provides the capacity to manage account and systems access controls
657 and policies. During the remaining life-cycle of the Samba-3 series it is possible the new tools may
658 be implemented to aid in this important area.
659 </p><p>
660 Domain global policy controls available in Windows NT4 compared with Samba
661 is shown in <a class="link" href="passdb.html#policycontrols" title="Table 11.1. NT4 Domain v's Samba Policy Controls">NT4 Domain v's Samba Policy Controls</a>.
662 </p><div class="table"><a name="policycontrols"></a><p class="title"><b>Table 11.1. NT4 Domain v's Samba Policy Controls</b></p><div class="table-contents"><table summary="NT4 Domain v's Samba Policy Controls" border="1"><colgroup><col align="left"><col align="left"><col align="center"><col align="center"><col align="center"></colgroup><thead><tr><th align="left"><p>NT4 policy Name</p></th><th align="left"><p>Samba Policy Name</p></th><th align="center"><p>NT4 Range</p></th><th align="center"><p>Samba Range</p></th><th align="center"><p>Samba Default</p></th></tr></thead><tbody><tr><td align="left"><p>Maximum Password Age</p></td><td align="left"><p>maximum password age</p></td><td align="center"><p>0 - 999 (days)</p></td><td align="center"><p>0 - 4294967295 (sec)</p></td><td align="center"><p>4294967295</p></td></tr><tr><td align="left"><p>Minimum Password Age</p></td><td align="left"><p>minimum password age</p></td><td align="center"><p>0 - 999 (days)</p></td><td align="center"><p>0 - 4294967295 (sec)</p></td><td align="center"><p>0</p></td></tr><tr><td align="left"><p>Minimum Password Length</p></td><td align="left"><p>min password length</p></td><td align="center"><p>1 - 14 (Chars)</p></td><td align="center"><p>0 - 4294967295 (Chars)</p></td><td align="center"><p>5</p></td></tr><tr><td align="left"><p>Password Uniqueness</p></td><td align="left"><p>password history</p></td><td align="center"><p>0 - 23 (#)</p></td><td align="center"><p>0 - 4294967295 (#)</p></td><td align="center"><p>0</p></td></tr><tr><td align="left"><p>Account Lockout - Reset count after</p></td><td align="left"><p>reset count minutes</p></td><td align="center"><p>1 - 99998 (min)</p></td><td align="center"><p>0 - 4294967295 (min)</p></td><td align="center"><p>30</p></td></tr><tr><td align="left"><p>Lockout after bad logon attempts</p></td><td align="left"><p>bad lockout attempt</p></td><td align="center"><p>0 - 998 (#)</p></td><td align="center"><p>0 - 4294967295 (#)</p></td><td align="center"><p>0</p></td></tr><tr><td align="left"><p>*** Not Known ***</p></td><td align="left"><p>disconnect time</p></td><td align="center"><p>TBA</p></td><td align="center"><p>0 - 4294967295</p></td><td align="center"><p>0</p></td></tr><tr><td align="left"><p>Lockout Duration</p></td><td align="left"><p>lockout duration</p></td><td align="center"><p>1 - 99998 (min)</p></td><td align="center"><p>0 - 4294967295 (min)</p></td><td align="center"><p>30</p></td></tr><tr><td align="left"><p>Users must log on in order to change password</p></td><td align="left"><p>user must logon to change password</p></td><td align="center"><p>0/1</p></td><td align="center"><p>0 - 4294967295</p></td><td align="center"><p>0</p></td></tr><tr><td align="left"><p>*** Registry Setting ***</p></td><td align="left"><p>refuse machine password change</p></td><td align="center"><p>0/1</p></td><td align="center"><p>0 - 4294967295</p></td><td align="center"><p>0</p></td></tr></tbody></table></div></div><br class="table-break"><p>
668 security and policy settings. It is capable of all operations that smbpasswd can
669 do as well as a superset of them.
670 </p><p>
675 the import/export of account information from one passdb backend to another.
676 </p><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2591049"></a>User Account Management</h4></div></div></div><p>
684 The <code class="literal">pdbedit</code> tool, like the <code class="literal">smbpasswd</code> tool, requires
685 that a POSIX user account already exists in the UNIX/Linux system accounts database (backend).
686 Neither tool will call out to the operating system to create a user account because this is
687 considered to be the responsibility of the system administrator. When the Windows NT4 domain
688 user manager is used to add an account, Samba will implement the <code class="literal">add user script</code>
689 (as well as the other interface scripts) to ensure that user, group and machine accounts are
690 correctly created and changed. The use of the <code class="literal">pdbedit</code> tool does not
691 make use of these interface scripts.
692 </p><p>
695 Before attempting to use the <code class="literal">pdbedit</code> tool to manage user and machine
696 accounts, make certain that a system (POSIX) account has already been created.
697 </p><div class="sect4" lang="en"><div class="titlepage"><div><div><h5 class="title"><a name="id2591165"></a>Listing User and Machine Accounts</h5></div></div></div><p>
700 The following is an example of the user account information that is stored in
701 a tdbsam password backend. This listing was produced by running:
704 UNIX username: met
705 NT username: met
706 Account Flags: [U ]
709 Full Name: Melissa E Terpstra
710 Home Directory: \\frodo\met\Win9Profile
711 HomeDir Drive: H:
712 Logon Script: scripts\logon.bat
713 Profile Path: \\frodo\Profiles\met
714 Domain: MIDEARTH
715 Account desc:
716 Workstations: melbelle
717 Munged dial:
718 Logon time: 0
724 </pre><p>
725 </p><p>
731 AF6DD3FD4E2EA8BDE1695A3F05EFBF52:[U ]:LCT-42681AB8:
733 CC099521AD554A3C3CF2556274DBCFBC:[U ]:LCT-40D75B5B:
734 rcg:1002:E95D4331A6F23AF8AAD3B435B51404EE:
735 BB0F2C39B04CA6100F0E535DF8314B43:[U ]:LCT-40D7C5A3:
737 CE92C2F9471594CDC4E7860CA6BC62DB:[T ]:LCT-40DA501F:
738 met:1004:A2848CB7E076B435AAD3B435B51404EE:
739 F25F5D3405085C555236B80B7B22C0D2:[U ]:LCT-4244FAB8:
742 temptation$:1006:XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX:
743 A96703C014E404E33D4049F706C45EE9:[W ]:LCT-42BF0C57:
744 vaioboss$:1001:XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX:
747 B68EADCCD18E17503D3DAD3E6B0B9A75:[W ]:LCT-42B7979F:
748 marvel$:1011:BF709959C3C94E0B3958B7B84A3BB6F3:
749 C610EFE9A385A3E8AA46ADFD576E6881:[W ]:LCT-40F07A4
750 </pre><p>
757 The account information that was returned by this command in order from left to right
758 consists of the following colon separated data:
759 </p><div class="itemizedlist"><ul type="disc"><li><p>Login ID.</p></li><li><p>UNIX UID.</p></li><li><p>Microsoft LanManager password hash (password converted to upper-case then hashed).</p></li><li><p>Microsoft NT password hash (hash of the case-preserved password).</p></li><li><p>Samba SAM Account Flags.</p></li><li><p>The LCT data (password last change time).</p></li></ul></div><p>
762 The Account Flags parameters are documented in the <code class="literal">pdbedit</code> man page, and are
763 briefly documented in <a class="link" href="passdb.html#TOSHARG-acctflags" title="Account Flags Management">the Account Flags Management section</a>.
764 </p><p>
766 The LCT data consists of 8 hexadecimal characters representing the time since January 1, 1970, of
767 the time when the password was last changed.
768 </p></div><div class="sect4" lang="en"><div class="titlepage"><div><div><h5 class="title"><a name="id2591400"></a>Adding User Accounts</h5></div></div></div><p>
774 The <code class="literal">pdbedit</code> can be used to add a user account to a standalone server
775 or to a domain. In the example shown here the account for the user <code class="literal">vlaan</code>
776 has been created before attempting to add the SambaSAMAccount.
779 new password: secretpw
780 retype new password: secretpw
781 Unix username: vlaan
782 NT username: vlaan
783 Account Flags: [U ]
786 Full Name: Victor Laan
787 Home Directory: \\frodo\vlaan
788 HomeDir Drive: H:
789 Logon Script: scripts\logon.bat
790 Profile Path: \\frodo\profiles\vlaan
791 Domain: MIDEARTH
792 Account desc: Guest User
793 Workstations:
794 Munged dial:
795 Logon time: 0
801 Last bad password : 0
802 Bad password count : 0
803 Logon hours : FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
804 </pre><p>
805 </p></div><div class="sect4" lang="en"><div class="titlepage"><div><div><h5 class="title"><a name="id2591488"></a>Deleting Accounts</h5></div></div></div><p>
810 An account can be deleted from the SambaSAMAccount database
813 </pre><p>
814 The account is removed without further screen output. The account is removed only from the
815 SambaSAMAccount (passdb backend) database, it is not removed from the UNIX account backend.
816 </p><p>
819 The use of the NT4 domain user manager to delete an account will trigger the <em class="parameter"><code>delete user
821 </p></div><div class="sect4" lang="en"><div class="titlepage"><div><div><h5 class="title"><a name="id2591572"></a>Changing User Accounts</h5></div></div></div><p>
823 Refer to the <code class="literal">pdbedit</code> man page for a full synopsis of all operations
824 that are available with this tool.
825 </p><p>
827 An example of a simple change in the user account information is the change of the full name
828 information shown here:
831 ...
833 Full Name: Victor Aluicious Laan
834 Home Directory: \\frodo\vlaan
835 ...
836 </pre><p>
837 </p><p>
841 Let us assume for a moment that a user's password has expired and the user is unable to
842 change the password at this time. It may be necessary to give the user additional grace time
843 so that it is possible to continue to work with the account and the original password. This
844 demonstrates how the password expiration settings may be updated
847 ...
852 Bad password count : 2
853 ...
854 </pre><p>
857 The user has recorded 2 bad logon attempts and the next will lock the account, but the
858 password is also expired. Here is how this account can be reset:
861 ...
865 Last bad password : 0
866 Bad password count : 0
867 ...
868 </pre><p>
872 ...
876 ...
877 </pre><p>
878 Another way to use this tools is to set the date like this:
882 ...
886 ...
887 </pre><p>
890 Refer to the strptime man page for specific time format information.
891 </p><p>
894 Please refer to the pdbedit man page for further information relating to SambaSAMAccount
895 management.
896 </p><div class="sect5" lang="en"><div class="titlepage"><div><div><h6 class="title"><a name="TOSHARG-acctflags"></a>Account Flags Management</h6></div></div></div><p>
901 The Samba SAM account flags are properly called the ACB (account control block) within
902 the Samba source code. In some parts of the Samba source code they are referred to as the
903 account encode_bits, and also as the account control flags.
904 </p><p>
910 The manual adjustment of user, machine (workstation or server) or an inter-domain trust
911 account account flgas should not be necessary under normal conditions of use of Samba. On the other hand,
912 where this information becomes corrupted for some reason, the ability to correct the damaged data is certainly
913 useful. The tool of choice by which such correction can be affected is the <code class="literal">pdbedit</code> utility.
914 </p><p>
917 There have been a few requests for information regarding the account flags from developers
918 who are creating their own Samba management tools. An example of a need for information regarding
919 the proper management of the account flags is evident when developing scripts that will be used
920 to manage an LDAP directory.
921 </p><p>
925 These are listed in <a class="link" href="passdb.html#accountflags" title="Table 11.2. Samba SAM Account Control Block Flags">Samba SAM Account Control Block Flags</a>.
926 The order in which the flags are specified to the <code class="literal">pdbedit</code> command is not important.
927 In fact, they can be set without problem in any order in the SambaAcctFlags record in the LDAP directory.
928 </p><div class="table"><a name="accountflags"></a><p class="title"><b>Table 11.2. Samba SAM Account Control Block Flags</b></p><div class="table-contents"><table summary="Samba SAM Account Control Block Flags" border="1"><colgroup><col><col></colgroup><thead><tr><th align="center">Flag</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">D</td><td align="left">Account is disabled.</td></tr><tr><td align="center">H</td><td align="left">A home directory is required.</td></tr><tr><td align="center">I</td><td align="left">An inter-domain trust account.</td></tr><tr><td align="center">L</td><td align="left">Account has been auto-locked.</td></tr><tr><td align="center">M</td><td align="left">An MNS (Microsoft network service) logon account.</td></tr><tr><td align="center">N</td><td align="left">Password not required.</td></tr><tr><td align="center">S</td><td align="left">A server trust account.</td></tr><tr><td align="center">T</td><td align="left">Temporary duplicate account entry.</td></tr><tr><td align="center">U</td><td align="left">A normal user account.</td></tr><tr><td align="center">W</td><td align="left">A workstation trust account.</td></tr><tr><td align="center">X</td><td align="left">Password does not expire.</td></tr></tbody></table></div></div><br class="table-break"><p>
931 An example of use of the <code class="literal">pdbedit</code> utility to set the account control flags
932 is shown here:
935 Unix username: jht
936 NT username: jht
937 Account Flags: [DHULX ]
940 Full Name: John H Terpstra,Utah Office
941 Home Directory: \\aurora\jht
942 HomeDir Drive: H:
943 Logon Script: scripts\logon.bat
944 Profile Path: \\aurora\profiles\jht
945 Domain: MIDEARTH
946 Account desc: BluntObject
947 Workstations:
948 Logon time: 0
950 Kickoff time: 0
954 Last bad password : 0
955 Bad password count : 0
956 Logon hours : FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
957 </pre><p>
959 The flags can be reset to the default settings by executing:
962 Unix username: jht
963 NT username: jht
964 Account Flags: [U ]
967 Full Name: John H Terpstra,Utah Office
968 Home Directory: \\aurora\jht
969 HomeDir Drive: H:
970 Logon Script: scripts\logon.bat
971 Profile Path: \\aurora\profiles\jht
972 Domain: MIDEARTH
973 Account desc: BluntObject
974 Workstations:
975 Logon time: 0
977 Kickoff time: 0
981 Last bad password : 0
982 Bad password count : 0
983 Logon hours : FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
984 </pre><p>
985 </p></div></div><div class="sect4" lang="en"><div class="titlepage"><div><div><h5 class="title"><a name="id2592233"></a>Domain Account Policy Managment</h5></div></div></div><p>
988 To view the domain account access policies that may be configured execute:
991 No account policy by that name
992 Account policy names are :
993 min password length
994 password history
995 user must logon to change password
996 maximum password age
997 minimum password age
998 lockout duration
999 reset count minutes
1000 bad lockout attempt
1001 disconnect time
1002 refuse machine password change
1003 </pre><p>
1004 </p><p>
1005 Commands will be executed to establish controls for our domain as follows:
1006 </p><div class="orderedlist"><ol type="1"><li><p>min password length = 8 characters.</p></li><li><p>password history = last 4 passwords.</p></li><li><p>maximum password age = 90 days.</p></li><li><p>minimum password age = 7 days.</p></li><li><p>bad lockout attempt = 8 bad logon attempts.</p></li><li><p>lockout duration = forever, account must be manually reenabled.</p></li></ol></div><p>
1007 The following command execution will achieve these settings:
1010 account policy value for min password length was 5
1011 account policy value for min password length is now 8
1013 account policy value for password history was 0
1014 account policy value for password history is now 4
1016 account policy value for maximum password age was 4294967295
1017 account policy value for maximum password age is now 7776000
1019 account policy value for minimum password age was 0
1020 account policy value for minimum password age is now 7
1022 account policy value for bad lockout attempt was 0
1023 account policy value for bad lockout attempt is now 8
1025 account policy value for lockout duration was 30
1026 account policy value for lockout duration is now 4294967295
1027 </pre><p>
1028 </p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>
1029 To set the maximum (infinite) lockout time use the value of -1.
1030 </p></div><div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Warning</h3><p>
1031 Account policies must be set individually on each PDC and BDC. At this time (Samba 3.0.11 to Samba 3.0.14a)
1032 account policies are not replicated automatically. This may be fixed before Samba 3.0.20 ships or some
1033 time there after. Please check the WHATSNEW.txt file in the Samba-3 tarball for specific update notiations
1034 regarding this facility.
1035 </p></div></div></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2592394"></a>Account Import/Export</h4></div></div></div><p>
1040 databases from one backend to another. For example, to import/export accounts from an
1041 old <code class="filename">smbpasswd</code> database to a <em class="parameter"><code>tdbsam</code></em>
1042 backend:
1046 <code class="prompt">root# </code><strong class="userinput"><code>pdbedit -i smbpasswd -e tdbsam</code></strong>
1047 </pre><p>
1048 </p></li><li><p>
1050 Replace the <em class="parameter"><code>smbpasswd</code></em> with <em class="parameter"><code>tdbsam</code></em> in the
1051 <em class="parameter"><code>passdb backend</code></em> configuration in <code class="filename">smb.conf</code>.
1052 </p></li></ol></div></div></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2592519"></a>Password Backends</h2></div></div></div><p>
1055 Samba offers flexibility in backend account database design. The flexibility is immediately obvious as one
1056 begins to explore this capability. Recent changes to Samba (since 3.0.23) have removed the mulitple backend
1057 feature in order to simplify problems that broke some installations. This removal has made the internal
1058 operation of Samba-3 more consistent and predictable.
1059 </p><p>
1062 Beginning with Samba 3.0.23 it is no longer possible to specify use of mulitple passdb backends. Earlier
1063 versions of Samba-3 made it possible to specify multiple password backends, and even multiple
1064 backends of the same type. The multiple passdb backend capability caused many problems with name to SID and
1065 SID to name ID resolution. The Samba team wrestled with the challenges and decided that this feature needed
1066 to be removed.
1067 </p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2592573"></a>Plaintext</h3></div></div></div><p>
1074 Older versions of Samba retrieved user information from the UNIX user database
1075 and eventually some other fields from the file <code class="filename">/etc/samba/smbpasswd</code>
1077 SMB-specific data is stored at all. Instead, all operations are conducted via the way
1079 On most Linux systems, for example, all user and group resolution is done via PAM.
1080 </p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2592649"></a>smbpasswd: Encrypted Password Database</h3></div></div></div><p>
1085 Traditionally, when configuring <a class="link" href="smb.conf.5.html#ENCRYPTPASSWORDS" target="_top">encrypt passwords = yes</a>
1086 in Samba's <code class="filename">smb.conf</code> file, user account information such as username, LM/NT password hashes,
1087 password change times, and account flags have been stored in the <code class="filename">smbpasswd(5)</code>
1088 file. There are several disadvantages to this approach for sites with large numbers of users
1089 (counted in the thousands).
1092 The first problem is that all lookups must be performed sequentially. Given that
1093 there are approximately two lookups per domain logon (one during initial logon validation
1094 and one for a session connection setup, such as when mapping a network drive or printer), this
1095 is a performance bottleneck for large sites. What is needed is an indexed approach
1096 such as that used in databases.
1097 </p></li><li><p>
1103 The second problem is that administrators who desire to replicate an smbpasswd file
1104 to more than one Samba server are left to use external tools such as
1105 <code class="literal">rsync(1)</code> and <code class="literal">ssh(1)</code> and write custom,
1106 in-house scripts.
1107 </p></li><li><p>
1113 Finally, the amount of information that is stored in an smbpasswd entry leaves
1114 no room for additional attributes such as a home directory, password expiration time,
1115 or even a relative identifier (RID).
1116 </p></li></ul></div><p>
1121 As a result of these deficiencies, a more robust means of storing user attributes
1122 used by smbd was developed. The API that defines access to user accounts
1123 is commonly referred to as the samdb interface (previously, this was called the passdb
1124 API and is still so named in the Samba source code trees).
1125 </p><p>
1131 Samba provides an enhanced set of passdb backends that overcome the deficiencies
1132 of the smbpasswd plaintext database. These are tdbsam and ldapsam.
1133 Of these, ldapsam will be of most interest to large corporate or enterprise sites.
1134 </p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2592915"></a>tdbsam</h3></div></div></div><p>
1138 Samba can store user and machine account data in a “<span class="quote">TDB</span>” (trivial database).
1139 Using this backend does not require any additional configuration. This backend is
1140 recommended for new installations that do not require LDAP.
1141 </p><p>
1146 As a general guide, the Samba Team does not recommend using the tdbsam backend for sites
1147 that have 250 or more users. Additionally, tdbsam is not capable of scaling for use
1148 in sites that require PDB/BDC implementations that require replication of the account
1149 database. Clearly, for reason of scalability, the use of ldapsam should be encouraged.
1150 </p><p>
1154 The recommendation of a 250-user limit is purely based on the notion that this
1155 would generally involve a site that has routed networks, possibly spread across
1156 more than one physical location. The Samba Team has not at this time established
1157 the performance-based scalability limits of the tdbsam architecture.
1158 </p><p>
1163 There are sites that have thousands of users and yet require only one server.
1167 is not one pertaining to a limitation in the TDB storage system, it is based
1168 only on the need for a reliable distribution mechanism for the SambaSAMAccount
1169 backend.
1170 </p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2593073"></a>ldapsam</h3></div></div></div><p>
1174 There are a few points to stress that the ldapsam does not provide. The LDAP
1175 support referred to in this documentation does not include:
1176 </p><div class="itemizedlist"><ul type="disc"><li><p>A means of retrieving user account information from
1177 a Windows 200x Active Directory server.</p></li><li><p>A means of replacing /etc/passwd.</p></li></ul></div><p>
1182 The second item can be accomplished by using LDAP NSS and PAM modules. LGPL versions of these libraries can be
1183 obtained from <a class="ulink" href="http://www.padl.com/" target="_top">PADL Software</a>. More information about the
1184 configuration of these packages may be found in <a class="ulink" href="http://safari.oreilly.com/?XmlId=1-56592-491-6" target="_top">
1185 <span class="emphasis"><em>LDAP, System Administration</em></span> by Gerald Carter, Chapter 6, Replacing NIS"</a>.
1186 </p><p>
1190 This document describes how to use an LDAP directory for storing Samba user
1191 account information traditionally stored in the smbpasswd(5) file. It is
1192 assumed that the reader already has a basic understanding of LDAP concepts
1193 and has a working directory server already installed. For more information
1194 on LDAP architectures and directories, please refer to the following sites:
1195 </p><div class="itemizedlist"><ul type="disc"><li><p><a class="ulink" href="http://www.openldap.org/" target="_top">OpenLDAP</a></p></li><li><p><a class="ulink" href="http://www.sun.com/software/products/directory_srvr_ee/index.xml" target="_top">
1196 Sun One Directory Server</a></p></li><li><p><a class="ulink" href="http://www.novell.com/products/edirectory/" target="_top">Novell eDirectory</a></p></li><li><p><a class="ulink" href="http://www-306.ibm.com/software/tivoli/products/directory-server/" target="_top">IBM
1197 Tivoli Directory Server</a></p></li><li><p><a class="ulink" href="http://www.redhat.com/software/rha/directory/" target="_top">Red Hat Directory
1198 Server</a></p></li><li><p><a class="ulink" href="http://www.linuxsecurity.com/content/view/119229" target="_top">Fedora Directory
1199 Server</a></p></li></ul></div><p>
1200 Two additional Samba resources that may prove to be helpful are:
1203 The <a class="ulink" href="http://www.unav.es/cti/ldap-smb/ldap-smb-3-howto.html" target="_top">Samba-PDC-LDAP-HOWTO</a>
1204 maintained by Ignacio Coupeau.
1205 </p></li><li><p>
1209 The NT migration scripts from <a class="ulink" href="http://samba.idealx.org/" target="_top">IDEALX</a> that are
1210 geared to manage users and groups in such a Samba-LDAP domain controller configuration.
1211 Idealx also produced the smbldap-tools and the Interactive Console Management tool.
1212 </p></li></ul></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2593320"></a>Supported LDAP Servers</h4></div></div></div><p>
1217 The LDAP ldapsam code was developed and tested using the OpenLDAP 2.x server and
1218 client libraries. The same code should work with Netscape's Directory Server and client SDK.
1219 However, there are bound to be compile errors and bugs. These should not be hard to fix.
1220 Please submit fixes via the process outlined in <a class="link" href="bugreport.html" title="Chapter 40. Reporting Bugs">Reporting Bugs</a>.
1221 </p><p>
1222 Samba is capable of working with any standards-compliant LDAP server.
1223 </p></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2593375"></a>Schema and Relationship to the RFC 2307 posixAccount</h4></div></div></div><p>
1224 Samba-3.0 includes the necessary schema file for OpenLDAP 2.x in the
1225 <code class="filename">examples/LDAP/samba.schema</code> directory of the source code distribution
1226 tarball. The schema entry for the sambaSamAccount ObjectClass is shown here:
1228 ObjectClass (1.3.6.1.4.1.7165.2.2.6 NAME 'sambaSamAccount' SUP top AUXILIARY
1229 DESC 'Samba-3.0 Auxiliary SAM Account'
1230 MUST ( uid $ sambaSID )
1231 MAY ( cn $ sambaLMPassword $ sambaNTPassword $ sambaPwdLastSet $
1232 sambaLogonTime $ sambaLogoffTime $ sambaKickoffTime $
1233 sambaPwdCanChange $ sambaPwdMustChange $ sambaAcctFlags $
1234 displayName $ sambaHomePath $ sambaHomeDrive $ sambaLogonScript $
1235 sambaProfilePath $ description $ sambaUserWorkstations $
1236 sambaPrimaryGroupSID $ sambaDomainName ))
1237 </pre><p>
1238 </p><p>
1243 The Samba Team owns the OID space used by the above schema and recommends its use.
1244 If you translate the schema to be used with Netscape DS, please submit the modified
1245 schema file as a patch to <a class="ulink" href="mailto:jerry@samba.org" target="_top">jerry@samba.org</a>.
1246 </p><p>
1254 Just as the smbpasswd file is meant to store information that provides information
1255 additional to a user's <code class="filename">/etc/passwd</code> entry, so is the sambaSamAccount
1256 object meant to supplement the UNIX user account information. A sambaSamAccount is an
1258 user account information in the LDAP directory, thus providing information needed
1259 for Samba account handling. However, there are several fields (e.g., uid) that overlap
1260 with the posixAccount ObjectClass outlined in RFC 2307. This is by design.
1261 </p><p>
1271 In order to store all user account information (UNIX and Samba) in the directory,
1272 it is necessary to use the sambaSamAccount and posixAccount ObjectClasses in
1273 combination. However, <code class="literal">smbd</code> will still obtain the user's UNIX account
1274 information via the standard C library calls, such as getpwnam().
1275 This means that the Samba server must also have the LDAP NSS library installed
1276 and functioning correctly. This division of information makes it possible to
1277 store all Samba account information in LDAP, but still maintain UNIX account
1278 information in NIS while the network is transitioning to a full LDAP infrastructure.
1279 </p></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2593602"></a>OpenLDAP Configuration</h4></div></div></div><p>
1284 To include support for the sambaSamAccount object in an OpenLDAP directory
1285 server, first copy the samba.schema file to slapd's configuration directory.
1286 The samba.schema file can be found in the directory <code class="filename">examples/LDAP</code>
1287 in the Samba source distribution.
1289 <code class="prompt">root# </code><strong class="userinput"><code>cp samba.schema /etc/openldap/schema/</code></strong>
1290 </pre><p>
1291 </p><p>
1300 Next, include the <code class="filename">samba.schema</code> file in <code class="filename">slapd.conf</code>.
1301 The sambaSamAccount object contains two attributes that depend on other schema
1302 files. The <em class="parameter"><code>uid</code></em> attribute is defined in <code class="filename">cosine.schema</code> and
1303 the <em class="parameter"><code>displayName</code></em> attribute is defined in the <code class="filename">inetorgperson.schema</code>
1304 file. Both of these must be included before the <code class="filename">samba.schema</code> file.
1306 ## /etc/openldap/slapd.conf
1308 ## schema files (core.schema is required by default)
1309 include /etc/openldap/schema/core.schema
1311 ## needed for sambaSamAccount
1312 include /etc/openldap/schema/cosine.schema
1313 include /etc/openldap/schema/inetorgperson.schema
1314 include /etc/openldap/schema/nis.schema
1315 include /etc/openldap/schema/samba.schema
1316 ....
1317 </pre><p>
1318 </p><p>
1323 It is recommended that you maintain some indices on some of the most useful attributes,
1324 as in the following example, to speed up searches made on sambaSamAccount ObjectClasses
1325 (and possibly posixAccount and posixGroup as well):
1326 </p><p>
1328 # Indices to maintain
1329 ## required by OpenLDAP
1330 index objectclass eq
1332 index cn pres,sub,eq
1333 index sn pres,sub,eq
1334 ## required to support pdb_getsampwnam
1335 index uid pres,sub,eq
1336 ## required to support pdb_getsambapwrid()
1337 index displayName pres,sub,eq
1339 ## uncomment these if you are storing posixAccount and
1340 ## posixGroup entries in the directory as well
1341 ##index uidNumber eq
1342 ##index gidNumber eq
1343 ##index memberUid eq
1345 index sambaSID eq
1346 index sambaPrimaryGroupSID eq
1347 index sambaDomainName eq
1348 index default sub
1349 </pre><p>
1350 </p><p>
1351 Create the new index by executing:
1354 </pre><p>
1355 </p><p>
1356 Remember to restart slapd after making these changes:
1358 <code class="prompt">root# </code><strong class="userinput"><code>/etc/init.d/slapd restart</code></strong>
1359 </pre><p>
1360 </p></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2593874"></a>Initialize the LDAP Database</h4></div></div></div><p>
1365 Before you can add accounts to the LDAP database, you must create the account containers
1366 that they will be stored in. The following LDIF file should be modified to match your
1367 needs (DNS entries, and so on):
1369 # Organization for Samba Base
1370 dn: dc=quenya,dc=org
1371 objectclass: dcObject
1372 objectclass: organization
1373 dc: quenya
1374 o: Quenya Org Network
1375 description: The Samba-3 Network LDAP Example
1377 # Organizational Role for Directory Management
1378 dn: cn=Manager,dc=quenya,dc=org
1379 objectclass: organizationalRole
1380 cn: Manager
1381 description: Directory Manager
1383 # Setting up container for Users OU
1384 dn: ou=People,dc=quenya,dc=org
1385 objectclass: top
1386 objectclass: organizationalUnit
1387 ou: People
1389 # Setting up admin handle for People OU
1390 dn: cn=admin,ou=People,dc=quenya,dc=org
1391 cn: admin
1392 objectclass: top
1393 objectclass: organizationalRole
1394 objectclass: simpleSecurityObject
1395 userPassword: {SSHA}c3ZM9tBaBo9autm1dL3waDS21+JSfQVz
1397 # Setting up container for groups
1398 dn: ou=Groups,dc=quenya,dc=org
1399 objectclass: top
1400 objectclass: organizationalUnit
1401 ou: Groups
1403 # Setting up admin handle for Groups OU
1404 dn: cn=admin,ou=Groups,dc=quenya,dc=org
1405 cn: admin
1406 objectclass: top
1407 objectclass: organizationalRole
1408 objectclass: simpleSecurityObject
1409 userPassword: {SSHA}c3ZM9tBaBo9autm1dL3waDS21+JSfQVz
1411 # Setting up container for computers
1412 dn: ou=Computers,dc=quenya,dc=org
1413 objectclass: top
1414 objectclass: organizationalUnit
1415 ou: Computers
1417 # Setting up admin handle for Computers OU
1418 dn: cn=admin,ou=Computers,dc=quenya,dc=org
1419 cn: admin
1420 objectclass: top
1421 objectclass: organizationalRole
1422 objectclass: simpleSecurityObject
1423 userPassword: {SSHA}c3ZM9tBaBo9autm1dL3waDS21+JSfQVz
1424 </pre><p>
1425 </p><p>
1428 The userPassword shown above should be generated using <code class="literal">slappasswd</code>.
1429 </p><p>
1432 The following command will then load the contents of the LDIF file into the LDAP
1433 database.
1436 <code class="prompt">$ </code><strong class="userinput"><code>slapadd -v -l initldap.dif</code></strong>
1437 </pre><p>
1438 </p><p>
1439 Do not forget to secure your LDAP server with an adequate access control list
1440 as well as an admin password.
1441 </p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>
1443 Before Samba can access the LDAP server, you need to store the LDAP admin password
1447 <code class="prompt">root# </code><strong class="userinput"><code>smbpasswd -w <em class="replaceable"><code>secret</code></em></code></strong>
1448 </pre><p>
1449 </p></div></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2594059"></a>Configuring Samba</h4></div></div></div><p>
1452 The following parameters are available in <code class="filename">smb.conf</code> only if your version of Samba was built with
1453 LDAP support. Samba automatically builds with LDAP support if the LDAP libraries are found. The
1454 best method to verify that Samba was built with LDAP support is:
1457 HAVE_LDAP_H
1458 HAVE_LDAP
1459 HAVE_LDAP_DOMAIN2HOSTLIST
1460 HAVE_LDAP_INIT
1461 HAVE_LDAP_INITIALIZE
1462 HAVE_LDAP_SET_REBIND_PROC
1463 HAVE_LIBLDAP
1464 LDAP_SET_REBIND_PROC_ARGS
1465 </pre><p>
1466 If the build of the <code class="literal">smbd</code> command you are using does not produce output
1467 that includes <code class="literal">HAVE_LDAP_H</code> it is necessary to discover why the LDAP headers
1468 and libraries were not found during compilation.
1469 </p><p>LDAP-related smb.conf options include these:
1470 </p><table class="simplelist" border="0" summary="Simple list"><tr><td><a class="indexterm" name="id2594130"></a><em class="parameter"><code>passdb backend = ldapsam:url</code></em></td></tr><tr><td><a class="indexterm" name="id2594142"></a></td></tr><tr><td><a class="indexterm" name="id2594149"></a></td></tr><tr><td><a class="indexterm" name="id2594156"></a></td></tr><tr><td><a class="indexterm" name="id2594163"></a></td></tr><tr><td><a class="indexterm" name="id2594170"></a></td></tr><tr><td><a class="indexterm" name="id2594177"></a></td></tr><tr><td><a class="indexterm" name="id2594184"></a></td></tr><tr><td><a class="indexterm" name="id2594191"></a></td></tr><tr><td><a class="indexterm" name="id2594198"></a></td></tr><tr><td><a class="indexterm" name="id2594204"></a></td></tr><tr><td><a class="indexterm" name="id2594211"></a></td></tr><tr><td><a class="indexterm" name="id2594218"></a></td></tr><tr><td><a class="indexterm" name="id2594225"></a></td></tr></table><p>
1471 </p><p>
1472 These are described in the <code class="filename">smb.conf</code> man page and so are not repeated here. However, an example
1473 for use with an LDAP directory is shown in <a class="link" href="passdb.html#confldapex" title="Example 11.2. Configuration with LDAP">the Configuration with LDAP.</a>
1474 </p><div class="example"><a name="confldapex"></a><p class="title"><b>Example 11.2. Configuration with LDAP</b></p><div class="example-contents"><table class="simplelist" border="0" summary="Simple list"><tr><td> </td></tr><tr><td><em class="parameter"><code>[global]</code></em></td></tr><tr><td><a class="indexterm" name="id2594277"></a><em class="parameter"><code>security = user</code></em></td></tr><tr><td><a class="indexterm" name="id2594288"></a><em class="parameter"><code>encrypt passwords = yes</code></em></td></tr><tr><td><a class="indexterm" name="id2594300"></a><em class="parameter"><code>netbios name = MORIA</code></em></td></tr><tr><td><a class="indexterm" name="id2594312"></a><em class="parameter"><code>workgroup = NOLDOR</code></em></td></tr><tr><td># LDAP related parameters:</td></tr><tr><td># Define the DN used when binding to the LDAP servers.</td></tr><tr><td># The password for this DN is not stored in smb.conf</td></tr><tr><td># Set it using 'smbpasswd -w secret' to store the</td></tr><tr><td># passphrase in the secrets.tdb file.</td></tr><tr><td># If the "ldap admin dn" value changes, it must be reset.</td></tr><tr><td><a class="indexterm" name="id2594348"></a><em class="parameter"><code>ldap admin dn = "cn=Manager,dc=quenya,dc=org"</code></em></td></tr><tr><td># SSL directory connections can be configured by:</td></tr><tr><td># ('off', 'start tls', or 'on' (default))</td></tr><tr><td><a class="indexterm" name="id2594369"></a><em class="parameter"><code>ldap ssl = start tls</code></em></td></tr><tr><td># syntax: passdb backend = ldapsam:ldap://server-name[:port]</td></tr><tr><td><a class="indexterm" name="id2594385"></a><em class="parameter"><code>passdb backend = ldapsam:ldap://frodo.quenya.org</code></em></td></tr><tr><td># smbpasswd -x delete the entire dn-entry</td></tr><tr><td><a class="indexterm" name="id2594401"></a><em class="parameter"><code>ldap delete dn = no</code></em></td></tr><tr><td># The machine and user suffix are added to the base suffix</td></tr><tr><td># wrote WITHOUT quotes. NULL suffixes by default</td></tr><tr><td><a class="indexterm" name="id2594421"></a><em class="parameter"><code>ldap user suffix = ou=People</code></em></td></tr><tr><td><a class="indexterm" name="id2594433"></a><em class="parameter"><code>ldap group suffix = ou=Groups</code></em></td></tr><tr><td><a class="indexterm" name="id2594445"></a><em class="parameter"><code>ldap machine suffix = ou=Computers</code></em></td></tr><tr><td># Trust UNIX account information in LDAP</td></tr><tr><td># (see the smb.conf man page for details)</td></tr><tr><td># Specify the base DN to use when searching the directory</td></tr><tr><td><a class="indexterm" name="id2594470"></a><em class="parameter"><code>ldap suffix = dc=quenya,dc=org</code></em></td></tr></table></div></div><br class="example-break"></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2594484"></a>Accounts and Groups Management</h4></div></div></div><p>
1477 Because user accounts are managed through the sambaSamAccount ObjectClass, you should
1478 modify your existing administration tools to deal with sambaSamAccount attributes.
1479 </p><p>
1483 Machine accounts are managed with the sambaSamAccount ObjectClass, just
1484 like user accounts. However, it is up to you to store those accounts
1485 in a different tree of your LDAP namespace. You should use
1487 “<span class="quote">ou=People,dc=quenya,dc=org</span>” to store users. Just configure your
1488 NSS and PAM accordingly (usually, in the <code class="filename">/etc/openldap/sldap.conf</code>
1489 configuration file).
1490 </p><p>
1495 In Samba-3, the group management system is based on POSIX
1496 groups. This means that Samba makes use of the posixGroup ObjectClass.
1497 For now, there is no NT-like group system management (global and local
1499 and, unlike MS Windows 2000 and Active Directory, Samba-3 does not
1500 support nested groups.
1501 </p></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2594597"></a>Security and sambaSamAccount</h4></div></div></div><p>
1503 There are two important points to remember when discussing the security
1504 of sambaSAMAccount entries in the directory.
1505 </p><div class="itemizedlist"><ul type="disc"><li><p><span class="emphasis"><em>Never</em></span> retrieve the SambaLMPassword or
1507 SambaNTPassword attribute values over an unencrypted LDAP session.</p></li><li><p><span class="emphasis"><em>Never</em></span> allow non-admin users to
1508 view the SambaLMPassword or SambaNTPassword attribute values.</p></li></ul></div><p>
1512 These password hashes are clear-text equivalents and can be used to impersonate
1513 the user without deriving the original clear-text strings. For more information
1514 on the details of LM/NT password hashes, refer to <a class="link" href="passdb.html" title="Chapter 11. Account Information Databases">the
1515 Account Information Database section</a>.
1516 </p><p>
1521 To remedy the first security issue, the <a class="link" href="smb.conf.5.html#LDAPSSL" target="_top">ldap ssl</a> <code class="filename">smb.conf</code>
1522 parameter defaults to require an encrypted session (<a class="link" href="smb.conf.5.html#LDAPSSL" target="_top">ldap ssl = on</a>) using the default port of <code class="constant">636</code> when
1523 contacting the directory server. When using an OpenLDAP server, it
1524 is possible to use the StartTLS LDAP extended operation in the place of LDAPS.
1525 In either case, you are strongly encouraged to use secure communications protocols
1526 (so do not set <a class="link" href="smb.conf.5.html#LDAPSSL" target="_top">ldap ssl = off</a>).
1527 </p><p>
1531 Note that the LDAPS protocol is deprecated in favor of the LDAPv3 StartTLS
1532 extended operation. However, the OpenLDAP library still provides support for
1533 the older method of securing communication between clients and servers.
1534 </p><p>
1538 The second security precaution is to prevent non-administrative users from
1539 harvesting password hashes from the directory. This can be done using the
1541 </p><p>
1544 access to attrs=SambaLMPassword,SambaNTPassword
1546 by * none
1547 </pre><p>
1548 </p></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2594833"></a>LDAP Special Attributes for sambaSamAccounts</h4></div></div></div><p> The sambaSamAccount ObjectClass is composed of the attributes shown in next tables: <a class="link" href="passdb.html#attribobjclPartA" title="Table 11.3. Attributes in the sambaSamAccount ObjectClass (LDAP), Part A">Part A</a>, and <a class="link" href="passdb.html#attribobjclPartB" title="Table 11.4. Attributes in the sambaSamAccount ObjectClass (LDAP), Part B">Part B</a>.
1549 </p><div class="table"><a name="attribobjclPartA"></a><p class="title"><b>Table 11.3. Attributes in the sambaSamAccount ObjectClass (LDAP), Part A</b></p><div class="table-contents"><table summary="Attributes in the sambaSamAccount ObjectClass (LDAP), Part A" border="1"><colgroup><col align="left"><col align="justify"></colgroup><tbody><tr><td align="left"><code class="constant">sambaLMPassword</code></td><td align="justify">The LanMan password 16-byte hash stored as a character
1550 representation of a hexadecimal string.</td></tr><tr><td align="left"><code class="constant">sambaNTPassword</code></td><td align="justify">The NT password 16-byte hash stored as a character
1551 representation of a hexadecimal string.</td></tr><tr><td align="left"><code class="constant">sambaPwdLastSet</code></td><td align="justify">The integer time in seconds since 1970 when the
1552 <code class="constant">sambaLMPassword</code> and <code class="constant">sambaNTPassword</code> attributes were last set.
1553 </td></tr><tr><td align="left"><code class="constant">sambaAcctFlags</code></td><td align="justify">String of 11 characters surrounded by square brackets [ ]
1554 representing account flags such as U (user), W (workstation), X (no password expiration),
1555 I (domain trust account), H (home dir required), S (server trust account),
1556 and D (disabled).</td></tr><tr><td align="left"><code class="constant">sambaLogonTime</code></td><td align="justify">Integer value currently unused.</td></tr><tr><td align="left"><code class="constant">sambaLogoffTime</code></td><td align="justify">Integer value currently unused.</td></tr><tr><td align="left"><code class="constant">sambaKickoffTime</code></td><td align="justify">Specifies the time (UNIX time format) when the user
1557 will be locked down and cannot login any longer. If this attribute is omitted, then the account will never expire.
1558 Using this attribute together with shadowExpire of the shadowAccount ObjectClass will enable accounts to
1559 expire completely on an exact date.</td></tr><tr><td align="left"><code class="constant">sambaPwdCanChange</code></td><td align="justify">Specifies the time (UNIX time format)
1560 after which the user is allowed to change his password. If this attribute is not set, the user will be free
1561 to change his password whenever he wants.</td></tr><tr><td align="left"><code class="constant">sambaPwdMustChange</code></td><td align="justify">Specifies the time (UNIX time format) when the user is
1562 forced to change his password. If this value is set to 0, the user will have to change his password at first login.
1563 If this attribute is not set, then the password will never expire.</td></tr><tr><td align="left"><code class="constant">sambaHomeDrive</code></td><td align="justify">Specifies the drive letter to which to map the
1564 UNC path specified by sambaHomePath. The drive letter must be specified in the form “<span class="quote">X:</span>”
1565 where X is the letter of the drive to map. Refer to the “<span class="quote">logon drive</span>” parameter in the
1566 smb.conf(5) man page for more information.</td></tr><tr><td align="left"><code class="constant">sambaLogonScript</code></td><td align="justify">The sambaLogonScript property specifies the path of
1567 the user's logon script, .CMD, .EXE, or .BAT file. The string can be null. The path
1568 is relative to the netlogon share. Refer to the <a class="link" href="smb.conf.5.html#LOGONSCRIPT" target="_top">logon script</a> parameter in the
1569 <code class="filename">smb.conf</code> man page for more information.</td></tr><tr><td align="left"><code class="constant">sambaProfilePath</code></td><td align="justify">Specifies a path to the user's profile.
1570 This value can be a null string, a local absolute path, or a UNC path. Refer to the
1571 <a class="link" href="smb.conf.5.html#LOGONPATH" target="_top">logon path</a> parameter in the <code class="filename">smb.conf</code> man page for more information.</td></tr><tr><td align="left"><code class="constant">sambaHomePath</code></td><td align="justify">The sambaHomePath property specifies the path of
1572 the home directory for the user. The string can be null. If sambaHomeDrive is set and specifies
1573 a drive letter, sambaHomePath should be a UNC path. The path must be a network
1574 UNC path of the form <code class="filename">\\server\share\directory</code>. This value can be a null string.
1575 Refer to the <code class="literal">logon home</code> parameter in the <code class="filename">smb.conf</code> man page for more information.
1576 </td></tr></tbody></table></div></div><br class="table-break"><div class="table"><a name="attribobjclPartB"></a><p class="title"><b>Table 11.4. Attributes in the sambaSamAccount ObjectClass (LDAP), Part B</b></p><div class="table-contents"><table summary="Attributes in the sambaSamAccount ObjectClass (LDAP), Part B" border="1"><colgroup><col align="left"><col align="justify"></colgroup><tbody><tr><td align="left"><code class="constant">sambaUserWorkstations</code></td><td align="justify">Here you can give a comma-separated list of machines
1577 on which the user is allowed to login. You may observe problems when you try to connect to a Samba domain member.
1578 Because domain members are not in this list, the domain controllers will reject them. Where this attribute is omitted,
1579 the default implies no restrictions.
1580 </td></tr><tr><td align="left"><code class="constant">sambaSID</code></td><td align="justify">The security identifier(SID) of the user.
1581 The Windows equivalent of UNIX UIDs.</td></tr><tr><td align="left"><code class="constant">sambaPrimaryGroupSID</code></td><td align="justify">The security identifier (SID) of the primary group
1582 of the user.</td></tr><tr><td align="left"><code class="constant">sambaDomainName</code></td><td align="justify">Domain the user is part of.</td></tr></tbody></table></div></div><br class="table-break"><p>
1585 The majority of these parameters are only used when Samba is acting as a PDC of
1586 a domain (refer to <a class="link" href="samba-pdc.html" title="Chapter 4. Domain Control">Domain Control</a>, for details on
1587 how to configure Samba as a PDC). The following four attributes
1588 are only stored with the sambaSamAccount entry if the values are non-default values:
1589 </p><div class="itemizedlist"><a class="indexterm" name="id2595210"></a><a class="indexterm" name="id2595216"></a><a class="indexterm" name="id2595223"></a><a class="indexterm" name="id2595230"></a><ul type="disc"><li><p>sambaHomePath</p></li><li><p>sambaLogonScript</p></li><li><p>sambaProfilePath</p></li><li><p>sambaHomeDrive</p></li></ul></div><p>
1593 These attributes are only stored with the sambaSamAccount entry if
1594 the values are non-default values. For example, assume MORIA has now been
1595 configured as a PDC and that <a class="link" href="smb.conf.5.html#LOGONHOME" target="_top">logon home = \\%L\%u</a> was defined in
1596 its <code class="filename">smb.conf</code> file. When a user named “<span class="quote">becky</span>” logs on to the domain,
1597 the <a class="link" href="smb.conf.5.html#LOGONHOME" target="_top">logon home</a> string is expanded to \\MORIA\becky.
1598 If the smbHome attribute exists in the entry “<span class="quote">uid=becky,ou=People,dc=samba,dc=org</span>”,
1599 this value is used. However, if this attribute does not exist, then the value
1600 of the <a class="link" href="smb.conf.5.html#LOGONHOME" target="_top">logon home</a> parameter is used in its place. Samba
1601 will only write the attribute value to the directory entry if the value is
1603 </p></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2595346"></a>Example LDIF Entries for a sambaSamAccount</h4></div></div></div><p>
1604 The following is a working LDIF that demonstrates the use of the SambaSamAccount ObjectClass:
1606 dn: uid=guest2, ou=People,dc=quenya,dc=org
1607 sambaLMPassword: 878D8014606CDA29677A44EFA1353FC7
1608 sambaPwdMustChange: 2147483647
1609 sambaPrimaryGroupSID: S-1-5-21-2447931902-1787058256-3961074038-513
1610 sambaNTPassword: 552902031BEDE9EFAAD3B435B51404EE
1611 sambaPwdLastSet: 1010179124
1612 sambaLogonTime: 0
1613 objectClass: sambaSamAccount
1614 uid: guest2
1615 sambaKickoffTime: 2147483647
1616 sambaAcctFlags: [UX ]
1617 sambaLogoffTime: 2147483647
1618 sambaSID: S-1-5-21-2447931902-1787058256-3961074038-5006
1619 sambaPwdCanChange: 0
1620 </pre><p>
1621 </p><p>
1622 The following is an LDIF entry for using both the sambaSamAccount and
1623 posixAccount ObjectClasses:
1625 dn: uid=gcarter, ou=People,dc=quenya,dc=org
1626 sambaLogonTime: 0
1627 displayName: Gerald Carter
1628 sambaLMPassword: 552902031BEDE9EFAAD3B435B51404EE
1629 sambaPrimaryGroupSID: S-1-5-21-2447931902-1787058256-3961074038-1201
1630 objectClass: posixAccount
1631 objectClass: sambaSamAccount
1632 sambaAcctFlags: [UX ]
1633 userPassword: {crypt}BpM2ej8Rkzogo
1634 uid: gcarter
1635 uidNumber: 9000
1636 cn: Gerald Carter
1637 loginShell: /bin/bash
1638 logoffTime: 2147483647
1639 gidNumber: 100
1640 sambaKickoffTime: 2147483647
1641 sambaPwdLastSet: 1010179230
1642 sambaSID: S-1-5-21-2447931902-1787058256-3961074038-5004
1643 homeDirectory: /home/moria/gcarter
1644 sambaPwdCanChange: 0
1645 sambaPwdMustChange: 2147483647
1646 sambaNTPassword: 878D8014606CDA29677A44EFA1353FC7
1647 </pre><p>
1648 </p></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2595394"></a>Password Synchronization</h4></div></div></div><p>
1649 Samba-3 and later can update the non-Samba (LDAP) password stored with an account. When
1650 using pam_ldap, this allows changing both UNIX and Windows passwords at once.
1651 </p><p>The <a class="link" href="smb.conf.5.html#LDAPPASSWDSYNC" target="_top">ldap passwd sync</a> options can have the values shown in
1652 <a class="link" href="passdb.html#ldappwsync" title="Table 11.5. Possible ldap passwd sync Values">Possible <span class="emphasis"><em>ldap passwd sync</em></span> Values</a>.</p><div class="table"><a name="ldappwsync"></a><p class="title"><b>Table 11.5. Possible <em class="parameter"><code>ldap passwd sync</code></em> Values</b></p><div class="table-contents"><table summary="Possible ldap passwd sync Values" border="1"><colgroup><col align="left"><col align="justify"></colgroup><thead><tr><th align="left">Value</th><th align="center">Description</th></tr></thead><tbody><tr><td align="left">yes</td><td align="justify"><p>When the user changes his password, update
1654 and the <code class="constant">password</code> fields.</p></td></tr><tr><td align="left">no</td><td align="justify"><p>Only update <code class="constant">SambaNTPassword</code> and
1655 <code class="constant">SambaLMPassword</code>.</p></td></tr><tr><td align="left">only</td><td align="justify"><p>Only update the LDAP password and let the LDAP server
1656 worry about the other fields. This option is only available on some LDAP servers and
1657 only when the LDAP server supports LDAP_EXOP_X_MODIFY_PASSWD.</p></td></tr></tbody></table></div></div><br class="table-break"><p>More information can be found in the <code class="filename">smb.conf</code> man page.</p></div><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2595546"></a>Using OpenLDAP Overlay for Password Synchronization</h4></div></div></div><p>
1658 Howard Chu has written a special overlay called <code class="literal">smbk5pwd</code>. This tool modifies the
1659 <code class="literal">SambaNTPassword</code>, <code class="literal">SambaLMPassword</code> and <code class="literal">Heimdal</code>
1660 hashes in an OpenLDAP entry when an LDAP_EXOP_X_MODIFY_PASSWD operation is performed.
1661 </p><p>
1662 The overlay is shipped with OpenLDAP-2.3 and can be found in the
1663 <code class="filename">contrib/slapd-modules/smbk5pwd</code> subdirectory. This module can also be used with
1664 OpenLDAP-2.2.
1665 </p></div></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2595597"></a>Common Errors</h2></div></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2595603"></a>Users Cannot Logon</h3></div></div></div><p>“<span class="quote">I've installed Samba, but now I can't log on with my UNIX account! </span>”</p><p>Make sure your user has been added to the current Samba <a class="link" href="smb.conf.5.html#PASSDBBACKEND" target="_top">passdb backend</a>.
1666 Read the <a class="link" href="passdb.html#acctmgmttools" title="Account Management Tools">Account Management Tools</a> for details.</p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2595641"></a>Configuration of <em class="parameter"><code>auth methods</code></em></h3></div></div></div><p>
1667 When explicitly setting an <a class="link" href="smb.conf.5.html#AUTHMETHODS" target="_top">auth methods</a> parameter,
1669 for example, <a class="link" href="smb.conf.5.html#AUTHMETHODS" target="_top">auth methods = guest sam</a>.
1670 </p></div></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="NetworkBrowsing.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="groupmapping.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 10. Network Browsing </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 12. Group Mapping: MS Windows and UNIX</td></tr></table></div></body></html>