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diff --git a/docs/htmldocs/Samba-LDAP-HOWTO.html b/docs/htmldocs/Samba-LDAP-HOWTO.html new file mode 100644 index 0000000000..76e94eeee0 --- /dev/null +++ b/docs/htmldocs/Samba-LDAP-HOWTO.html @@ -0,0 +1,654 @@ +<HTML +><HEAD +><TITLE +>Storing Samba's User/Machine Account information in an LDAP Directory</TITLE +><META +NAME="GENERATOR" +CONTENT="Modular DocBook HTML Stylesheet Version 1.57"></HEAD +><BODY +CLASS="ARTICLE" +BGCOLOR="#FFFFFF" +TEXT="#000000" +LINK="#0000FF" +VLINK="#840084" +ALINK="#0000FF" +><DIV +CLASS="ARTICLE" +><DIV +CLASS="TITLEPAGE" +><H1 +CLASS="TITLE" +><A +NAME="SAMBA-LDAP-HOWTO" +>Storing Samba's User/Machine Account information in an LDAP Directory</A +></H1 +><HR></DIV +><DIV +CLASS="SECT1" +><H1 +CLASS="SECT1" +><A +NAME="AEN3" +>Purpose</A +></H1 +><P +>This document describes how to use an LDAP directory for storing Samba user +account information normally 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 +><P +></P +><UL +><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 +><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 +>It may also be helpful to suppplement the reading of the HOWTO with +the <A +HREF="http://www.unav.es/cti/ldap-smb/ldap-smb-2_2-howto.html" +TARGET="_top" +>Samba-PDC-LDAP-HOWTO</A +> +maintained by Ignacio Coupeau.</P +></DIV +><DIV +CLASS="SECT1" +><HR><H1 +CLASS="SECT1" +><A +NAME="AEN17" +>Introduction</A +></H1 +><P +>Traditionally, when configuring <A +HREF="smb.conf.5.html#ENCRYPTPASSWORDS" +TARGET="_top" +>"encrypt +passwords = yes"</A +> in Samba's <TT +CLASS="FILENAME" +>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 +CLASS="FILENAME" +>smbpasswd(5)</TT +> file. There are several +disadvantages to this approach for sites with very large numbers of users (counted +in the thousands).</P +><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 non-optimal. What is needed is an indexed approach such as is used in +databases.</P +><P +>The second problem is that administrators which desired to replicate an +smbpasswd file to more than one Samba server were left to use external +tools such as <B +CLASS="COMMAND" +>rsync(1)</B +> and <B +CLASS="COMMAND" +>ssh(1)</B +> +and write custom, in-house scripts.</P +><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 +><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 referred to as the samdb interface (previously this was called the passdb +API, and is still so named in the CVS trees). In Samba 2.2.3, enabling support +for a samdb backend (e.g. <TT +CLASS="PARAMETER" +><I +>--with-ldapsam</I +></TT +> or +<TT +CLASS="PARAMETER" +><I +>--with-tdbsam</I +></TT +>) requires compile time support.</P +><P +>When compiling Samba to include the <TT +CLASS="PARAMETER" +><I +>--with-ldapsam</I +></TT +> autoconf +option, smbd (and associated tools) will store and lookup user accounts in +an LDAP directory. In reality, this is very easy to understand. If you are +comfortable with using an smbpasswd file, simply replace "smbpasswd" with +"LDAP directory" in all the documentation.</P +><P +>There are a few points to stress about what the <TT +CLASS="PARAMETER" +><I +>--with-ldapsam</I +></TT +> +does not provide. The LDAP support referred to in the this documentat does not +include:</P +><P +></P +><UL +><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 +><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 +>). However, +the details of configuring these packages i beyond the scope of this document.</P +></DIV +><DIV +CLASS="SECT1" +><HR><H1 +CLASS="SECT1" +><A +NAME="AEN42" +>Supported LDAP Servers</A +></H1 +><P +>The LDAP samdb code in 2.2.3 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 bounds to be compile errors and bugs. These should not be +hard to fix. If you are so inclined, please be sure to forward all pacthes to +<A +HREF="samba-patches@samba.org" +TARGET="_top" +>samba-patches@samba.org</A +> and +<A +HREF="jerry@samba.org" +TARGET="_top" +>jerry@samba.org</A +>.</P +></DIV +><DIV +CLASS="SECT1" +><HR><H1 +CLASS="SECT1" +><A +NAME="AEN47" +>Schema and Relationship to the RFC 2307 posixAccount</A +></H1 +><P +>Samba 2.2.3 includes the necessary schema file for OpenLDAP 2.0 in +<TT +CLASS="FILENAME" +>examples/LDAP/samba.schema</TT +>. (Note that this schema +file has been modified since the experimental support initially included +in 2.2.2). The sambaAccount objectclass is given here:</P +><P +><PRE +CLASS="PROGRAMLISTING" +>objectclass ( 1.3.1.5.1.4.1.7165.2.2.2 NAME 'sambaAccount' SUP top STRUCTURAL + 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 ))</PRE +></P +><P +>The samba.schema file has been formatted for OpenLDAP 2.0. The OID's are +owned by the Samba Team and as such as 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="jerry@samba.org" +TARGET="_top" +>jerry@samba.org</A +></P +><P +>Just as the smbpasswd file is mean to store information which supplements a +user's <TT +CLASS="FILENAME" +>/etc/passwd</TT +> entry, so is the sambaAccount object +meant to supplement the UNIX user account information. A sambaAccount is a +<TT +CLASS="CONSTANT" +>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 mkes it posible 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 infratrsucture.</P +><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 +CLASS="PROMPT" +>root# </TT +><B +CLASS="COMMAND" +>cp samba.schema /etc/openldap/schema/</B +></P +><P +>Next, include the <TT +CLASS="FILENAME" +>samba.schema</TT +> file in <TT +CLASS="FILENAME" +>slapd.conf</TT +>. +The sambaAccount object contains two attributes which depend upon other schema +files. The 'uid' attribute is defined in <TT +CLASS="FILENAME" +>cosine.schema</TT +> and +the 'displayName' attribute is defined in the <TT +CLASS="FILENAME" +>inetorgperson.schema</TT +> +file. Bother of these must be included before the <TT +CLASS="FILENAME" +>samba.schema</TT +> file.</P +><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 + +## uncomment this line if you want to support the RFC2307 (NIS) schema +## include /etc/openldap/schema/nis.schema + +....</PRE +></P +></DIV +><DIV +CLASS="SECT1" +><HR><H1 +CLASS="SECT1" +><A +NAME="AEN71" +>smb.conf LDAP parameters</A +></H1 +><P +>The following parameters are available in smb.conf only with <TT +CLASS="PARAMETER" +><I +>--with-ldapsam</I +></TT +> +was included with compiling Samba.</P +><P +></P +><UL +><LI +><P +><A +HREF="smb.conf.5.html#LDAPSSL" +TARGET="_top" +>ldap ssl</A +></P +></LI +><LI +><P +><A +HREF="smb.conf.5.html#LDAPSERVER" +TARGET="_top" +>ldap server</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 +></UL +><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 +><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 <TT +CLASS="REPLACEABLE" +><I +>secretpw</I +></TT +>' to store the + # passphrase in the secrets.tdb file. If the "ldap admin dn" values + # changes, this password will need to be reset. + ldap admin dn = "cn=Manager,dc=samba,dc=org" + + # specify the LDAP server's hostname (defaults to locahost) + ldap server = ahab.samba.org + + # Define the SSL option when connecting to the directory + # ('off', 'start tls', or 'on' (default)) + ldap ssl = start tls + + # 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 +></P +></DIV +><DIV +CLASS="SECT1" +><HR><H1 +CLASS="SECT1" +><A +NAME="AEN99" +>Security and sambaAccount</A +></H1 +><P +>There are two important points to remember when discussing the security +of sambaAccount entries in the directory.</P +><P +></P +><UL +><LI +><P +><I +CLASS="EMPHASIS" +>Never</I +> retrieve the lmPassword or + ntPassword attribute values over and unencrypted LDAP session.</P +></LI +><LI +><P +><I +CLASS="EMPHASIS" +>Never</I +> allow non-admin users to + view the lmPassword or ntPassword attribute values.</P +></LI +></UL +><P +>These password hashes are clear text equivalents and can be used to impersonate +the user without deriving the original clear text strings.</P +><P +>To remedy the first security issue, the "ldap ssl" smb.conf parameter defaults +to require an encrypted session (<B +CLASS="COMMAND" +>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 +CLASS="COMMAND" +>ldap ssl = off</B +>).</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 +CLASS="FILENAME" +>slapd.conf</TT +>:</P +><P +><PRE +CLASS="PROGRAMLISTING" +>## allow users to update their own password, but not to browse others +access to attrs=userPassword,lmPassword,ntPassword + by self write + by * auth</PRE +></P +><P +>You may of course, add in write access to administrative DN's as necessary.</P +></DIV +><DIV +CLASS="SECT1" +><HR><H1 +CLASS="SECT1" +><A +NAME="AEN118" +></A +></H1 +><P +>There are currently four sambaAccount attributes which map directly onto +<TT +CLASS="FILENAME" +>smb.conf</TT +> parameters.</P +><P +></P +><UL +><LI +><P +>smbHome -> "logon home"</P +></LI +><LI +><P +>profilePath -> "logon path"</P +></LI +><LI +><P +>homeDrive -> "logon drive"</P +></LI +><LI +><P +>scriptPath -> "logon script"</P +></LI +></UL +><P +>First of all, these parameters are only used when Samba is acting as a +PDC or 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). +Furthermore, 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 +CLASS="COMMAND" +>logon home = \\%L\%u</B +> was defined in +its <TT +CLASS="FILENAME" +>smb.conf</TT +> file. Assuming <TT +CLASS="FILENAME" +>smb.conf</TT +> +also contains , when a user named "becky" logons to the domain, the <TT +CLASS="PARAMETER" +><I +>logon +home</I +></TT +> string is expanded to \\TASHTEGO\becky.</P +><P +>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 <TT +CLASS="PARAMETER" +><I +>logon home</I +></TT +> parameter is used in its place. Samba +will only write the attribute value to the directory entry is the value is +something other than the default (e.g. \\MOBY\becky).</P +></DIV +><DIV +CLASS="SECT1" +><HR><H1 +CLASS="SECT1" +><A +NAME="AEN139" +>Example LDIF Entries for a sambaAccount</A +></H1 +><P +>The following is a working LDIF with the inclusion of the posixAccount objectclass:</P +><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 +><P +>The following is an LDIF entry for using both the sambaAccount and +posixAccount objectclasses:</P +><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 +></P +></DIV +><DIV +CLASS="SECT1" +><HR><H1 +CLASS="SECT1" +><A +NAME="AEN147" +>Comments</A +></H1 +><P +>Please mail all comments regarding this HOWTO to <A +HREF="mailto:jerry@samba.org" +TARGET="_top" +>jerry@samba.org</A +>. This documents was +last updated to reflect the Samba 2.2.3 release. </P +></DIV +></DIV +></BODY +></HTML +>
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