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diff --git a/docs/htmldocs/passdb.html b/docs/htmldocs/passdb.html new file mode 100644 index 0000000000..9f313ee123 --- /dev/null +++ b/docs/htmldocs/passdb.html @@ -0,0 +1,518 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Chapter 10. User information database</title><link rel="stylesheet" href="samba.css" type="text/css"><meta name="generator" content="DocBook XSL Stylesheets V1.59.1"><link rel="home" href="index.html" title="SAMBA Project Documentation"><link rel="up" href="optional.html" title="Part III. Advanced Configuration"><link rel="previous" href="NetworkBrowsing.html" title="Chapter 9. Samba / MS Windows Network Browsing Guide"><link rel="next" href="unix-permissions.html" title="Chapter 11. UNIX Permission Bits and Windows NT Access Control Lists"></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 10. User information database</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="unix-permissions.html">Next</a></td></tr></table><hr></div><div class="chapter" lang="en"><div class="titlepage"><div><h2 class="title"><a name="passdb"></a>Chapter 10. User information database</h2></div><div><div class="author"><h3 class="author">Jelmer R. Vernooij</h3><div class="affiliation"><span class="orgname">The Samba Team<br></span><div class="address"><p><tt><<a href="mailto:jelmer@samba.org">jelmer@samba.org</a>></tt></p></div></div></div></div><div><div class="author"><h3 class="author">Gerald (Jerry) Carter</h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><tt><<a href="mailto:jerry@samba.org">jerry@samba.org</a>></tt></p></div></div></div></div><div><div class="author"><h3 class="author">Jeremy Allison</h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><tt><<a href="mailto:jra@samba.org">jra@samba.org</a>></tt></p></div></div></div></div><div><div class="author"><h3 class="author">John H. Terpstra</h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><tt><<a href="mailto:jht@samba.org">jht@samba.org</a>></tt></p></div></div></div></div><div><div class="author"><h3 class="author">Olivier (lem) Lemaire</h3><div class="affiliation"><span class="orgname">IDEALX<br></span><div class="address"><p><tt><<a href="mailto:olem@IDEALX.org">olem@IDEALX.org</a>></tt></p></div></div></div></div><div><p class="pubdate">February 2003</p></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><a href="passdb.html#id2882995">Introduction</a></dt><dt><a href="passdb.html#id2883048">Important Notes About Security</a></dt><dd><dl><dt><a href="passdb.html#id2883210">Advantages of SMB Encryption</a></dt><dt><a href="passdb.html#id2883249">Advantages of non-encrypted passwords</a></dt></dl></dd><dt><a href="passdb.html#id2883283">The smbpasswd Command</a></dt><dt><a href="passdb.html#id2883464">Plain text</a></dt><dt><a href="passdb.html#id2883493">TDB</a></dt><dt><a href="passdb.html#id2883509">LDAP</a></dt><dd><dl><dt><a href="passdb.html#id2883516">Introduction</a></dt><dt><a href="passdb.html#id2883617">Encrypted Password Database</a></dt><dt><a href="passdb.html#id2883756">Supported LDAP Servers</a></dt><dt><a href="passdb.html#id2883794">Schema and Relationship to the RFC 2307 posixAccount</a></dt><dt><a href="passdb.html#id2883904">Configuring Samba with LDAP</a></dt><dt><a href="passdb.html#id2884200">Accounts and Groups management</a></dt><dt><a href="passdb.html#id2884237">Security and sambaAccount</a></dt><dt><a href="passdb.html#id2884352">LDAP specials attributes for sambaAccounts</a></dt><dt><a href="passdb.html#id2884633">Example LDIF Entries for a sambaAccount</a></dt></dl></dd><dt><a href="passdb.html#id2884689">MySQL</a></dt><dd><dl><dt><a href="passdb.html#id2884696">Creating the database</a></dt><dt><a href="passdb.html#id2884750">Configuring</a></dt><dt><a href="passdb.html#id2884895">Using plaintext passwords or encrypted password</a></dt><dt><a href="passdb.html#id2884925">Getting non-column data from the table</a></dt></dl></dd><dt><a href="passdb.html#id2884968">XML</a></dt></dl></div><div class="sect1" lang="en"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2882995"></a>Introduction</h2></div></div><p>Old windows clients send plain text passwords over the wire. + Samba can check these passwords by crypting them and comparing them + to the hash stored in the unix user database. + </p><p> + Newer windows clients send encrypted passwords (so-called + Lanman and NT hashes) over + the wire, instead of plain text passwords. The newest clients + will only send encrypted passwords and refuse to send plain text + passwords, unless their registry is tweaked. + </p><p>These passwords can't be converted to unix style encrypted + passwords. Because of that you can't use the standard unix + user database, and you have to store the Lanman and NT hashes + somewhere else. </p><p>Next to a differently encrypted passwords, + windows also stores certain data for each user + that is not stored in a unix user database, e.g. + workstations the user may logon from, the location where his/her + profile is stored, etc. + Samba retrieves and stores this information using a "passdb backend". + Commonly + available backends are LDAP, plain text file, MySQL and nisplus. + For more information, see the documentation about the + <b>passdb backend = </b> parameter. + </p></div><div class="sect1" lang="en"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2883048"></a>Important Notes About Security</h2></div></div><p>The unix and SMB password encryption techniques seem similar + on the surface. This similarity is, however, only skin deep. The unix + scheme typically sends clear text passwords over the network when + logging in. This is bad. The SMB encryption scheme never sends the + cleartext password over the network but it does store the 16 byte + hashed values on disk. This is also bad. Why? Because the 16 byte hashed + values are a "password equivalent". You cannot derive the user's + password from them, but they could potentially be used in a modified + client to gain access to a server. This would require considerable + technical knowledge on behalf of the attacker but is perfectly possible. + You should thus treat the data stored in whatever + passdb backend you use (smbpasswd file, ldap, mysql) as though it contained the + cleartext passwords of all your users. Its contents must be kept + secret, and the file should be protected accordingly.</p><p>Ideally we would like a password scheme which neither requires + plain text passwords on the net or on disk. Unfortunately this + is not available as Samba is stuck with being compatible with + other SMB systems (WinNT, WfWg, Win95 etc). </p><div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Warning</h3><p>Note that Windows NT 4.0 Service pack 3 changed the + default for permissible authentication so that plaintext + passwords are <span class="emphasis"><em>never</em></span> sent over the wire. + The solution to this is either to switch to encrypted passwords + with Samba or edit the Windows NT registry to re-enable plaintext + passwords. See the document WinNT.txt for details on how to do + this.</p><p>Other Microsoft operating systems which also exhibit + this behavior includes</p><p> These versions of MS Windows do not support full domain + security protocols, although they may log onto a domain environment. + Of these Only MS Windows XP Home does NOT support domain logons.</p><table class="simplelist" border="0" summary="Simple list"><tr><td>MS DOS Network client 3.0 with + the basic network redirector installed</td></tr><tr><td>Windows 95 with the network redirector + update installed</td></tr><tr><td>Windows 98 [se]</td></tr><tr><td>Windows Me</td></tr><tr><td>Windows XP Home</td></tr></table><p> The following versions of MS Windows fully support domain + security protocols.</p><table class="simplelist" border="0" summary="Simple list"><tr><td>Windows NT 3.5x</td></tr><tr><td>Windows NT 4.0</td></tr><tr><td>Windows 2000 Professional</td></tr><tr><td>Windows 200x Server/Advanced Server</td></tr><tr><td>Windows XP Professional</td></tr></table></div><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>All current release of + Microsoft SMB/CIFS clients support authentication via the + SMB Challenge/Response mechanism described here. Enabling + clear text authentication does not disable the ability + of the client to participate in encrypted authentication.</p></div><p>MS Windows clients will cache the encrypted password alone. + Even when plain text passwords are re-enabled, through the appropriate + registry change, the plain text password is NEVER cached. This means that + in the event that a network connections should become disconnected (broken) + only the cached (encrypted) password will be sent to the resource server + to affect a auto-reconnect. If the resource server does not support encrypted + passwords the auto-reconnect will fail. <span class="emphasis"><em>USE OF ENCRYPTED PASSWORDS + IS STRONGLY ADVISED.</em></span></p><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2883210"></a>Advantages of SMB Encryption</h3></div></div><table class="simplelist" border="0" summary="Simple list"><tr><td>Plain text passwords are not passed across + the network. Someone using a network sniffer cannot just + record passwords going to the SMB server.</td></tr><tr><td>WinNT doesn't like talking to a server + that does not support encrypted passwords. It will refuse + to browse the server if the server is also in user level + security mode. It will insist on prompting the user for the + password on each connection, which is very annoying. The + only things you can do to stop this is to use SMB encryption. + </td></tr><tr><td>Encrypted password support allows automatic share + (resource) reconnects.</td></tr></table></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2883249"></a>Advantages of non-encrypted passwords</h3></div></div><table class="simplelist" border="0" summary="Simple list"><tr><td>Plain text passwords are not kept + on disk, and are NOT cached in memory. </td></tr><tr><td>Uses same password file as other unix + services such as login and ftp</td></tr><tr><td>Use of other services (such as telnet and ftp) which + send plain text passwords over the net, so sending them for SMB + isn't such a big deal.</td></tr></table></div></div><div class="sect1" lang="en"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2883283"></a>The smbpasswd Command</h2></div></div><p>The smbpasswd utility is a utility similar to the + <b>passwd</b> or <b>yppasswd</b> programs. + It maintains the two 32 byte password fields in the passdb backend. </p><p><b>smbpasswd</b> works in a client-server mode + where it contacts the local smbd to change the user's password on its + behalf. This has enormous benefits - as follows.</p><p><b>smbpasswd</b> has the capability + to change passwords on Windows NT servers (this only works when + the request is sent to the NT Primary Domain Controller if you + are changing an NT Domain user's password).</p><p>To run smbpasswd as a normal user just type :</p><p><tt>$ </tt><b><tt>smbpasswd</tt></b></p><p><tt>Old SMB password: </tt><b><tt><type old value here - + or hit return if there was no old password></tt></b></p><p><tt>New SMB Password: </tt><b><tt><type new value> + </tt></b></p><p><tt>Repeat New SMB Password: </tt><b><tt><re-type new value + </tt></b></p><p>If the old value does not match the current value stored for + that user, or the two new values do not match each other, then the + password will not be changed.</p><p>If invoked by an ordinary user it will only allow the user + to change his or her own Samba password.</p><p>If run by the root user smbpasswd may take an optional + argument, specifying the user name whose SMB password you wish to + change. Note that when run as root smbpasswd does not prompt for + or check the old password value, thus allowing root to set passwords + for users who have forgotten their passwords.</p><p><b>smbpasswd</b> is designed to work in the same way + and be familiar to UNIX users who use the <b>passwd</b> or + <b>yppasswd</b> commands.</p><p>For more details on using <b>smbpasswd</b> refer + to the man page which will always be the definitive reference.</p></div><div class="sect1" lang="en"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2883464"></a>Plain text</h2></div></div><p> +Older versions of samba retrieved user information from the unix user database +and eventually some other fields from the file <tt>/etc/samba/smbpasswd</tt> +or <tt>/etc/smbpasswd</tt>. When password encryption is disabled, no +data is stored at all. +</p></div><div class="sect1" lang="en"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2883493"></a>TDB</h2></div></div><p>Samba can also store the user data in a "TDB" (Trivial Database). Using this backend +doesn't require any additional configuration. This backend is recommended for new installations that +don not require LDAP. +</p></div><div class="sect1" lang="en"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2883509"></a>LDAP</h2></div></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2883516"></a>Introduction</h3></div></div><p> +This document describes how to use an LDAP directory for storing Samba user +account information traditionally stored in the smbpasswd(5) file. It is +assumed that the reader already has a basic understanding of LDAP concepts +and has a working directory server already installed. For more information +on LDAP architectures and Directories, please refer to the following sites. +</p><div class="itemizedlist"><ul type="disc"><li><p>OpenLDAP - <a href="http://www.openldap.org/" target="_top">http://www.openldap.org/</a></p></li><li><p>iPlanet Directory Server - <a href="http://iplanet.netscape.com/directory" target="_top">http://iplanet.netscape.com/directory</a></p></li></ul></div><p> +Note that <a href="http://www.ora.com/" target="_top">O'Reilly Publishing</a> is working on +a guide to LDAP for System Administrators which has a planned release date of +early summer, 2002. +</p><p> +Two additional Samba resources which may prove to be helpful are +</p><div class="itemizedlist"><ul type="disc"><li><p>The <a href="http://www.unav.es/cti/ldap-smb/ldap-smb-3-howto.html" target="_top">Samba-PDC-LDAP-HOWTO</a> + maintained by Ignacio Coupeau.</p></li><li><p>The NT migration scripts from <a href="http://samba.idealx.org/" target="_top">IDEALX</a> that are + geared to manage users and group in such a Samba-LDAP Domain Controller configuration. + </p></li></ul></div></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2883617"></a>Encrypted Password Database</h3></div></div><p> +Traditionally, when configuring <a href="smb.conf.5.html#ENCRYPTPASSWORDS" target="_top">"encrypt +passwords = yes"</a> in Samba's <tt>smb.conf</tt> file, user account +information such as username, LM/NT password hashes, password change times, and account +flags have been stored in the <tt>smbpasswd(5)</tt> file. There are several +disadvantages to this approach for sites with very large numbers of users (counted +in the thousands). +</p><div class="itemizedlist"><ul type="disc"><li><p> +The first is that all lookups must be performed sequentially. Given that +there are approximately two lookups per domain logon (one for a normal +session connection such as when mapping a network drive or printer), this +is a performance bottleneck for large sites. What is needed is an indexed approach +such as is used in databases. +</p></li><li><p> +The second problem is that administrators who desired to replicate a +smbpasswd file to more than one Samba server were left to use external +tools such as <b>rsync(1)</b> and <b>ssh(1)</b> +and wrote custom, in-house scripts. +</p></li><li><p> +And finally, the amount of information which is stored in an +smbpasswd entry leaves no room for additional attributes such as +a home directory, password expiration time, or even a Relative +Identified (RID). +</p></li></ul></div><p> +As a result of these defeciencies, a more robust means of storing user attributes +used by smbd was developed. The API which defines access to user accounts +is commonly referred to as the samdb interface (previously this was called the passdb +API, and is still so named in the CVS trees). +</p><p> +There are a few points to stress about that the ldapsam +does not provide. The LDAP support referred to in the this documentation does not +include: +</p><div class="itemizedlist"><ul type="disc"><li><p>A means of retrieving user account information from + an Windows 2000 Active Directory server.</p></li><li><p>A means of replacing /etc/passwd.</p></li></ul></div><p> +The second item can be accomplished by using LDAP NSS and PAM modules. LGPL +versions of these libraries can be obtained from PADL Software +(<a href="http://www.padl.com/" target="_top">http://www.padl.com/</a>). More +information about the configuration of these packages may be found at "LDAP, +System Administration; Gerald Carter, O'Reilly; Chapter 6: Replacing NIS". +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2883756"></a>Supported LDAP Servers</h3></div></div><p> +The LDAP samdb code in 2.2.3 (and later) has been developed and tested +using the OpenLDAP 2.0 server and client libraries. +The same code should be able to work with Netscape's Directory Server +and client SDK. However, due to lack of testing so far, there are bound +to be compile errors and bugs. These should not be hard to fix. +If you are so inclined, please be sure to forward all patches to +<a href="mailto:samba-patches@samba.org" target="_top">samba-patches@samba.org</a> and +<a href="mailto:jerry@samba.org" target="_top">jerry@samba.org</a>. +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2883794"></a>Schema and Relationship to the RFC 2307 posixAccount</h3></div></div><p> +Samba 3.0 includes the necessary schema file for OpenLDAP 2.0 in +<tt>examples/LDAP/samba.schema</tt>. The sambaAccount objectclass is given here: +</p><pre class="programlisting"> +objectclass ( 1.3.1.5.1.4.1.7165.2.2.2 NAME 'sambaAccount' SUP top AUXILIARY + DESC 'Samba Account' + MUST ( uid $ rid ) + MAY ( cn $ lmPassword $ ntPassword $ pwdLastSet $ logonTime $ + logoffTime $ kickoffTime $ pwdCanChange $ pwdMustChange $ acctFlags $ + displayName $ smbHome $ homeDrive $ scriptPath $ profilePath $ + description $ userWorkstations $ primaryGroupID $ domain )) +</pre><p> +The samba.schema file has been formatted for OpenLDAP 2.0. The OID's are +owned by the Samba Team and as such is legal to be openly published. +If you translate the schema to be used with Netscape DS, please +submit the modified schema file as a patch to <a href="mailto:jerry@samba.org" target="_top">jerry@samba.org</a> +</p><p> +Just as the smbpasswd file is meant to store information which supplements a +user's <tt>/etc/passwd</tt> entry, so is the sambaAccount object +meant to supplement the UNIX user account information. A sambaAccount is a +<tt>STRUCTURAL</tt> objectclass so it can be stored individually +in the directory. However, there are several fields (e.g. uid) which overlap +with the posixAccount objectclass outlined in RFC2307. This is by design. +</p><p> +In order to store all user account information (UNIX and Samba) in the directory, +it is necessary to use the sambaAccount and posixAccount objectclasses in +combination. However, smbd will still obtain the user's UNIX account +information via the standard C library calls (e.g. getpwnam(), et. al.). +This means that the Samba server must also have the LDAP NSS library installed +and functioning correctly. This division of information makes it possible to +store all Samba account information in LDAP, but still maintain UNIX account +information in NIS while the network is transitioning to a full LDAP infrastructure. +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2883904"></a>Configuring Samba with LDAP</h3></div></div><div class="sect3" lang="en"><div class="titlepage"><div><h4 class="title"><a name="id2883912"></a>OpenLDAP configuration</h4></div></div><p> +To include support for the sambaAccount object in an OpenLDAP directory +server, first copy the samba.schema file to slapd's configuration directory. +</p><p> +<tt>root# </tt><b><tt>cp samba.schema /etc/openldap/schema/</tt></b> +</p><p> +Next, include the <tt>samba.schema</tt> file in <tt>slapd.conf</tt>. +The sambaAccount object contains two attributes which depend upon other schema +files. The 'uid' attribute is defined in <tt>cosine.schema</tt> and +the 'displayName' attribute is defined in the <tt>inetorgperson.schema</tt> +file. Both of these must be included before the <tt>samba.schema</tt> file. +</p><pre class="programlisting"> +## /etc/openldap/slapd.conf + +## schema files (core.schema is required by default) +include /etc/openldap/schema/core.schema + +## needed for sambaAccount +include /etc/openldap/schema/cosine.schema +include /etc/openldap/schema/inetorgperson.schema +include /etc/openldap/schema/samba.schema +include /etc/openldap/schema/nis.schema + +.... +</pre><p> +It is recommended that you maintain some indices on some of the most usefull attributes, +like in the following example, to speed up searches made on sambaAccount objectclasses +(and possibly posixAccount and posixGroup as well). +</p><pre class="programlisting"> +# Indices to maintain +## required by OpenLDAP 2.0 +index objectclass eq + +## support pb_getsampwnam() +index uid pres,eq +## support pdb_getsambapwrid() +index rid eq + +## uncomment these if you are storing posixAccount and +## posixGroup entries in the directory as well +##index uidNumber eq +##index gidNumber eq +##index cn eq +##index memberUid eq + +# (both fetched via ldapsearch): +index primaryGroupID eq +index displayName pres,eq + +</pre></div><div class="sect3" lang="en"><div class="titlepage"><div><h4 class="title"><a name="id2884030"></a>Configuring Samba</h4></div></div><p> +The following parameters are available in smb.conf only with <i><tt>--with-ldapsam</tt></i> +was included when compiling Samba. +</p><div class="itemizedlist"><ul type="disc"><li><p><a href="smb.conf.5.html#PASSDBBACKEND" target="_top">passdb backend [ldapsam|ldapsam_nua]:url</a></p></li><li><p><a href="smb.conf.5.html#LDAPSSL" target="_top">ldap ssl</a></p></li><li><p><a href="smb.conf.5.html#LDAPADMINDN" target="_top">ldap admin dn</a></p></li><li><p><a href="smb.conf.5.html#LDAPSUFFIX" target="_top">ldap suffix</a></p></li><li><p><a href="smb.conf.5.html#LDAPFILTER" target="_top">ldap filter</a></p></li><li><p><a href="smb.conf.5.html#LDAPPORT" target="_top">ldap port</a></p></li><li><p><a href="smb.conf.5.html#LDAPMACHINSUFFIX" target="_top">ldap machine suffix</a></p></li><li><p><a href="smb.conf.5.html#LDAPUSERSUFFIX" target="_top">ldap user suffix</a></p></li><li><p><a href="smb.conf.5.html#LDAPDELETEDN" target="_top">ldap delete dn</a></p></li></ul></div><p> +These are described in the <a href="smb.conf.5.html" target="_top">smb.conf(5)</a> man +page and so will not be repeated here. However, a sample smb.conf file for +use with an LDAP directory could appear as +</p><pre class="programlisting"> +## /usr/local/samba/lib/smb.conf +[global] + security = user + encrypt passwords = yes + + netbios name = TASHTEGO + workgroup = NARNIA + + # ldap related parameters + + # define the DN to use when binding to the directory servers + # The password for this DN is not stored in smb.conf. Rather it + # must be set by using 'smbpasswd -w <i><tt>secretpw</tt></i>' to store the + # passphrase in the secrets.tdb file. If the "ldap admin dn" values + # change, this password will need to be reset. + ldap admin dn = "cn=Samba Manager,ou=people,dc=samba,dc=org" + + # Define the SSL option when connecting to the directory + # ('off', 'start tls', or 'on' (default)) + ldap ssl = start tls + + passdb backend ldapsam:ldap://ahab.samba.org + + # smbpasswd -x delete the entire dn-entry + ldap delete dn = no + + # the machine and user suffix added to the base suffix + # wrote WITHOUT quotes. NULL siffixes by default + ldap user suffix = ou=People + ldap machine suffix = ou=Systems + + # define the port to use in the LDAP session (defaults to 636 when + # "ldap ssl = on") + ldap port = 389 + + # specify the base DN to use when searching the directory + ldap suffix = "ou=people,dc=samba,dc=org" + + # generally the default ldap search filter is ok + # ldap filter = "(&(uid=%u)(objectclass=sambaAccount))" +</pre></div></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2884200"></a>Accounts and Groups management</h3></div></div><p> +As users accounts are managed thru the sambaAccount objectclass, you should +modify your existing administration tools to deal with sambaAccount attributes. +</p><p> +Machines accounts are managed with the sambaAccount objectclass, just +like users accounts. However, it's up to you to store thoses accounts +in a different tree of you LDAP namespace: you should use +"ou=Groups,dc=plainjoe,dc=org" to store groups and +"ou=People,dc=plainjoe,dc=org" to store users. Just configure your +NSS and PAM accordingly (usually, in the /etc/ldap.conf configuration +file). +</p><p> +In Samba release 3.0, the group management system is based on posix +groups. This means that Samba makes usage of the posixGroup objectclass. +For now, there is no NT-like group system management (global and local +groups). +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2884237"></a>Security and sambaAccount</h3></div></div><p> +There are two important points to remember when discussing the security +of sambaAccount entries in the directory. +</p><div class="itemizedlist"><ul type="disc"><li><p><span class="emphasis"><em>Never</em></span> retrieve the lmPassword or + ntPassword attribute values over an unencrypted LDAP session.</p></li><li><p><span class="emphasis"><em>Never</em></span> allow non-admin users to + view the lmPassword or ntPassword attribute values.</p></li></ul></div><p> +These password hashes are clear text equivalents and can be used to impersonate +the user without deriving the original clear text strings. For more information +on the details of LM/NT password hashes, refer to the <a href="passdb.html" title="Chapter 10. User information database">User Database</a> of the Samba-HOWTO-Collection. +</p><p> +To remedy the first security issue, the "ldap ssl" smb.conf parameter defaults +to require an encrypted session (<b>ldap ssl = on</b>) using +the default port of 636 +when contacting the directory server. When using an OpenLDAP 2.0 server, it +is possible to use the use the StartTLS LDAP extended operation in the place of +LDAPS. In either case, you are strongly discouraged to disable this security +(<b>ldap ssl = off</b>). +</p><p> +Note that the LDAPS protocol is deprecated in favor of the LDAPv3 StartTLS +extended operation. However, the OpenLDAP library still provides support for +the older method of securing communication between clients and servers. +</p><p> +The second security precaution is to prevent non-administrative users from +harvesting password hashes from the directory. This can be done using the +following ACL in <tt>slapd.conf</tt>: +</p><pre class="programlisting"> +## allow the "ldap admin dn" access, but deny everyone else +access to attrs=lmPassword,ntPassword + by dn="cn=Samba Admin,ou=people,dc=plainjoe,dc=org" write + by * none +</pre></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2884352"></a>LDAP specials attributes for sambaAccounts</h3></div></div><p> +The sambaAccount objectclass is composed of the following attributes: +</p><div class="itemizedlist"><ul type="disc"><li><p><tt>lmPassword</tt>: the LANMAN password 16-byte hash stored as a character + representation of a hexidecimal string.</p></li><li><p><tt>ntPassword</tt>: the NT password hash 16-byte stored as a character + representation of a hexidecimal string.</p></li><li><p><tt>pwdLastSet</tt>: The integer time in seconds since 1970 when the + <tt>lmPassword</tt> and <tt>ntPassword</tt> attributes were last set. + </p></li><li><p><tt>acctFlags</tt>: string of 11 characters surrounded by square brackets [] + representing account flags such as U (user), W(workstation), X(no password expiration), and + D(disabled).</p></li><li><p><tt>logonTime</tt>: Integer value currently unused</p></li><li><p><tt>logoffTime</tt>: Integer value currently unused</p></li><li><p><tt>kickoffTime</tt>: Integer value currently unused</p></li><li><p><tt>pwdCanChange</tt>: Integer value currently unused</p></li><li><p><tt>pwdMustChange</tt>: Integer value currently unused</p></li><li><p><tt>homeDrive</tt>: specifies the drive letter to which to map the + UNC path specified by homeDirectory. The drive letter must be specified in the form "X:" + where X is the letter of the drive to map. Refer to the "logon drive" parameter in the + smb.conf(5) man page for more information.</p></li><li><p><tt>scriptPath</tt>: The scriptPath property specifies the path of + the user's logon script, .CMD, .EXE, or .BAT file. The string can be null. The path + is relative to the netlogon share. Refer to the "logon script" parameter in the + smb.conf(5) man page for more information.</p></li><li><p><tt>profilePath</tt>: specifies a path to the user's profile. + This value can be a null string, a local absolute path, or a UNC path. Refer to the + "logon path" parameter in the smb.conf(5) man page for more information.</p></li><li><p><tt>smbHome</tt>: The homeDirectory property specifies the path of + the home directory for the user. The string can be null. If homeDrive is set and specifies + a drive letter, homeDirectory should be a UNC path. The path must be a network + UNC path of the form \\server\share\directory. This value can be a null string. + Refer to the "logon home" parameter in the smb.conf(5) man page for more information. + </p></li><li><p><tt>userWorkstation</tt>: character string value currently unused. + </p></li><li><p><tt>rid</tt>: the integer representation of the user's relative identifier + (RID).</p></li><li><p><tt>primaryGroupID</tt>: the relative identifier (RID) of the primary group + of the user.</p></li></ul></div><p> +The majority of these parameters are only used when Samba is acting as a PDC of +a domain (refer to the <a href="Samba-PDC-HOWTO.html" target="_top">Samba-PDC-HOWTO</a> for details on +how to configure Samba as a Primary Domain Controller). The following four attributes +are only stored with the sambaAccount entry if the values are non-default values: +</p><div class="itemizedlist"><ul type="disc"><li><p>smbHome</p></li><li><p>scriptPath</p></li><li><p>logonPath</p></li><li><p>homeDrive</p></li></ul></div><p> +These attributes are only stored with the sambaAccount entry if +the values are non-default values. For example, assume TASHTEGO has now been +configured as a PDC and that <b>logon home = \\%L\%u</b> was defined in +its <tt>smb.conf</tt> file. When a user named "becky" logons to the domain, +the <i><tt>logon home</tt></i> string is expanded to \\TASHTEGO\becky. +If the smbHome attribute exists in the entry "uid=becky,ou=people,dc=samba,dc=org", +this value is used. However, if this attribute does not exist, then the value +of the <i><tt>logon home</tt></i> parameter is used in its place. Samba +will only write the attribute value to the directory entry if the value is +something other than the default (e.g. \\MOBY\becky). +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2884633"></a>Example LDIF Entries for a sambaAccount</h3></div></div><p> +The following is a working LDIF with the inclusion of the posixAccount objectclass: +</p><pre class="programlisting"> +dn: uid=guest2, ou=people,dc=plainjoe,dc=org +ntPassword: 878D8014606CDA29677A44EFA1353FC7 +pwdMustChange: 2147483647 +primaryGroupID: 1201 +lmPassword: 552902031BEDE9EFAAD3B435B51404EE +pwdLastSet: 1010179124 +logonTime: 0 +objectClass: sambaAccount +uid: guest2 +kickoffTime: 2147483647 +acctFlags: [UX ] +logoffTime: 2147483647 +rid: 19006 +pwdCanChange: 0 +</pre><p> +The following is an LDIF entry for using both the sambaAccount and +posixAccount objectclasses: +</p><pre class="programlisting"> +dn: uid=gcarter, ou=people,dc=plainjoe,dc=org +logonTime: 0 +displayName: Gerald Carter +lmPassword: 552902031BEDE9EFAAD3B435B51404EE +primaryGroupID: 1201 +objectClass: posixAccount +objectClass: sambaAccount +acctFlags: [UX ] +userPassword: {crypt}BpM2ej8Rkzogo +uid: gcarter +uidNumber: 9000 +cn: Gerald Carter +loginShell: /bin/bash +logoffTime: 2147483647 +gidNumber: 100 +kickoffTime: 2147483647 +pwdLastSet: 1010179230 +rid: 19000 +homeDirectory: /home/tashtego/gcarter +pwdCanChange: 0 +pwdMustChange: 2147483647 +ntPassword: 878D8014606CDA29677A44EFA1353FC7 +</pre></div></div><div class="sect1" lang="en"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2884689"></a>MySQL</h2></div></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2884696"></a>Creating the database</h3></div></div><p> +You either can set up your own table and specify the field names to pdb_mysql (see below +for the column names) or use the default table. The file <tt>examples/pdb/mysql/mysql.dump</tt> +contains the correct queries to create the required tables. Use the command : + +<b>mysql -u<i><tt>username</tt></i> -h<i><tt>hostname</tt></i> -p<i><tt>password</tt></i> <i><tt>databasename</tt></i> > <tt>/path/to/samba/examples/pdb/mysql/mysql.dump</tt></b> + +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2884750"></a>Configuring</h3></div></div><p>This plugin lacks some good documentation, but here is some short info:</p><p>Add a the following to the <b>passdb backend</b> variable in your <tt>smb.conf</tt>: +</p><pre class="programlisting"> +passdb backend = [other-plugins] mysql:identifier [other-plugins] +</pre><p> +</p><p>The identifier can be any string you like, as long as it doesn't collide with +the identifiers of other plugins or other instances of pdb_mysql. If you +specify multiple pdb_mysql.so entries in 'passdb backend', you also need to +use different identifiers! +</p><p> +Additional options can be given thru the smb.conf file in the [global] section. +</p><pre class="programlisting"> +identifier:mysql host - host name, defaults to 'localhost' +identifier:mysql password +identifier:mysql user - defaults to 'samba' +identifier:mysql database - defaults to 'samba' +identifier:mysql port - defaults to 3306 +identifier:table - Name of the table containing users +</pre><div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Warning</h3><p> +Since the password for the mysql user is stored in the +smb.conf file, you should make the the smb.conf file +readable only to the user that runs samba. This is considered a security +bug and will be fixed soon. +</p></div><p>Names of the columns in this table(I've added column types those columns should have first):</p><pre class="programlisting"> +identifier:logon time column - int(9) +identifier:logoff time column - int(9) +identifier:kickoff time column - int(9) +identifier:pass last set time column - int(9) +identifier:pass can change time column - int(9) +identifier:pass must change time column - int(9) +identifier:username column - varchar(255) - unix username +identifier:domain column - varchar(255) - NT domain user is part of +identifier:nt username column - varchar(255) - NT username +identifier:fullname column - varchar(255) - Full name of user +identifier:home dir column - varchar(255) - Unix homedir path +identifier:dir drive column - varchar(2) - Directory drive path (eg: 'H:') +identifier:logon script column - varchar(255) + - Batch file to run on client side when logging on +identifier:profile path column - varchar(255) - Path of profile +identifier:acct desc column - varchar(255) - Some ASCII NT user data +identifier:workstations column - varchar(255) + - Workstations user can logon to (or NULL for all) +identifier:unknown string column - varchar(255) - unknown string +identifier:munged dial column - varchar(255) - ? +identifier:user sid column - varchar(255) - NT user SID +identifier:group sid column - varchar(255) - NT group ID +identifier:lanman pass column - varchar(255) - encrypted lanman password +identifier:nt pass column - varchar(255) - encrypted nt passwd +identifier:plain pass column - varchar(255) - plaintext password +identifier:acct control column - int(9) - nt user data +identifier:unknown 3 column - int(9) - unknown +identifier:logon divs column - int(9) - ? +identifier:hours len column - int(9) - ? +identifier:unknown 5 column - int(9) - unknown +identifier:unknown 6 column - int(9) - unknown +</pre><p> +Eventually, you can put a colon (:) after the name of each column, which +should specify the column to update when updating the table. You can also +specify nothing behind the colon - then the data from the field will not be +updated. +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2884895"></a>Using plaintext passwords or encrypted password</h3></div></div><p> +I strongly discourage the use of plaintext passwords, however, you can use them: +</p><p> +If you would like to use plaintext passwords, set +'identifier:lanman pass column' and 'identifier:nt pass column' to +'NULL' (without the quotes) and 'identifier:plain pass column' to the +name of the column containing the plaintext passwords. +</p><p> +If you use encrypted passwords, set the 'identifier:plain pass +column' to 'NULL' (without the quotes). This is the default. +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><h3 class="title"><a name="id2884925"></a>Getting non-column data from the table</h3></div></div><p> +It is possible to have not all data in the database and making some 'constant'. +</p><p> +For example, you can set 'identifier:fullname column' to : +<b>CONCAT(First_name,' ',Sur_name)</b> +</p><p> +Or, set 'identifier:workstations column' to : +<b>NULL</b></p><p>See the MySQL documentation for more language constructs.</p></div></div><div class="sect1" lang="en"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2884968"></a>XML</h2></div></div><p>This module requires libxml2 to be installed.</p><p>The usage of pdb_xml is pretty straightforward. To export data, use: +</p><p> + <b><tt>pdbedit -e xml:filename</tt></b> +</p><p> +(where filename is the name of the file to put the data in) +</p><p> +To import data, use: +<b><tt>pdbedit -i xml:filename -e current-pdb</tt></b> +</p><p> +Where filename is the name to read the data from and current-pdb to put it in. +</p></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="unix-permissions.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 9. Samba / MS Windows Network Browsing Guide </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 11. 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