Chapter 11. Account Information Databases

-Samba-3 implements a new capability to work concurrently with multiple account backends. -The possible new combinations of password backends allows Samba-3 a degree of flexibility +Chapter 11. Account Information Databases

Chapter 11. Account Information Databases
Prev	Part III. Advanced Configuration	Next

Chapter 11. Account Information Databases

Jelmer R. Vernooij

The Samba Team

<jelmer@samba.org>

Gerald (Jerry) Carter

Samba Team

<jerry@samba.org>

Jeremy Allison

Samba Team

<jra@samba.org>

John H. Terpstra

Samba Team

<jht@samba.org>

Olivier (lem) Lemaire

IDEALX

<olem@IDEALX.org>

May 24, 2003

+Samba 3 implements a new capability to work concurrently with multiple account backends. +The possible new combinations of password backends allows Samba 3 a degree of flexibility and scalability that previously could be achieved only with MS Windows Active Directory. This chapter describes the new functionality and how to get the most out of it.

In the course of development of Samba-3, a number of requests were received to provide the ability to migrate MS Windows NT4 SAM accounts to Samba-3 without the need to provide -matching Unix/Linux accounts. We called this the Non Unix Accounts (NUA) +matching UNIX/Linux accounts. We called this the Non UNIX Accounts (NUA) capability. The intent was that an administrator could decide to use the tdbsam -backend and by simply specifying "passdb backend = tdbsam_nua, guest" -this would allow Samba-3 to implement a solution that did not use Unix accounts per se. Late +backend and by simply specifying passdb backend = tdbsam_nua +this would allow Samba-3 to implement a solution that did not use UNIX accounts per se. Late in the development cycle, the team doing this work hit upon some obstacles that prevents this solution from being used. Given the delays with Samba-3 release a decision was made to NOT deliver this functionality until a better method of recognising NT Group SIDs from NT User SIDs could be found. This feature may thus return during the life cycle for the Samba-3 series.

Note

-Samba-3.0.0 does NOT support Non-Unix Account (NUA) operation. -

Features and Benefits

+Samba-3 does NOT support Non-UNIX Account (NUA) operation for user accounts. +Samba-3 does support NUA operation for machine accounts. +

Features and Benefits

Samba-3 provides for complete backwards compatibility with Samba-2.2.x functionality as follows: -

Backwards Compatibility Backends

Plain Text:

- This option uses nothing but the Unix/Linux /etc/passwd +

Backwards Compatibility Backends

Plain Text:: + This option uses nothing but the UNIX/Linux /etc/passwd style back end. On systems that have PAM (Pluggable Authentication Modules) support all PAM modules are supported. The behaviour is just as it was with Samba-2.2.x, and the protocol limitations imposed by MS Windows clients @@ -42,13 +43,9 @@ as follows: This option is provided primarily as a migration tool, although there is no reason to force migration at this time. Note that this tool will eventually be deprecated. -

New Backends

Samba-3 introduces the following new password backend capabilities: -

New Backends

guest:

- This is always required as the last backend specified. - It provides the ability to handle guest account requirements for access to - resources like IPC$ which is used for browsing. -

tdbsam:

tdbsam:: This backend provides a rich database backend for local servers. This backend is NOT suitable for multiple domain controller (ie: PDC + one or more BDC) installations. @@ -90,10 +87,7 @@ Samba-3 introduces the following new password backend capabilities: The xmlsam option can be useful for account migration between database backends or backups. Use of this tool will allow the data to be edited before migration into another backend format. -
nisplussam:: - The NIS+ based passdb backend. Takes name NIS domain as an - optional argument. Only works with Sun NIS+ servers. -

Technical Information

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.

@@ -108,10 +102,10 @@ Samba-3 introduces the following new password backend capabilities: In addition to 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 the users' profile is stored, and so on. Samba retrieves and stores this - information using a passdb backend. Commonly available backends are LDAP, plain text + information using a passdb backend. Commonly available backends are LDAP, plain text file, MySQL and nisplus. For more information, see the man page for smb.conf regarding the - passdb backend parameter. -

Important Notes About Security

+ passdb backend parameter. +

Figure 11.1. IDMAP

Important Notes About Security

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 @@ -135,12 +129,12 @@ Samba-3 introduces the following new password backend capabilities:

The following versions of MS Windows do not support full domain security protocols, although they may log onto a domain environment: -

MS DOS Network client 3.0 with the basic network redirector installed

Windows 95 with the network redirector update installed

Windows 98 [se]

Windows Me

Note

MS DOS Network client 3.0 with the basic network redirector installed
Windows 95 with the network redirector update installed
Windows 98 [se]
Windows Me

Note

MS Windows XP Home does not have facilities to become a domain member and it can not participate in domain logons.

The following versions of MS Windows fully support domain security protocols. -

Windows NT 3.5x

Windows NT 4.0

Windows 2000 Professional

Windows 200x Server/Advanced Server

Windows XP Professional

Windows NT 3.5x
Windows NT 4.0
Windows 2000 Professional
Windows 200x Server/Advanced Server
Windows XP Professional

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. @@ -153,7 +147,7 @@ Samba-3 introduces the following new password backend capabilities: (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. USE OF ENCRYPTED PASSWORDS IS STRONGLY ADVISED. -

Advantages of Encrypted Passwords

Plain text passwords are not passed across +
Advantages of Encrypted Passwords
- Plain text passwords are not passed across the network. Someone using a network sniffer cannot just record passwords going to the SMB server.
- Plain text passwords are not stored anywhere in memory or on disk.
- WinNT doesn't like talking to a server @@ -164,32 +158,44 @@ Samba-3 introduces the following new password backend capabilities: only things you can do to stop this is to use SMB encryption.
- Encrypted password support allows automatic share (resource) reconnects.
- Encrypted passwords are essential for PDC/BDC - operation.
Advantages of non-encrypted passwords
- Plain text passwords are not kept + operation.
Advantages of non-encrypted passwords
- Plain text passwords are not kept on disk, and are NOT cached in memory.
- Uses same password file as other unix services such as login and ftp
- 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.

Mapping User Identifiers between MS Windows and Unix

- Every operation in Unix/Linux requires a user identifier (UID), just as in + isn't such a big deal.

Mapping User Identifiers between MS Windows and UNIX

+ Every operation in UNIX/Linux requires a user identifier (UID), just as in MS Windows NT4 / 200x this requires a Security Identifier (SID). Samba provides - two means for mapping an MS Windows user to a Unix/Linux UID. + two means for mapping an MS Windows user to a UNIX/Linux UID.

Firstly, all Samba SAM (Security Account Manager database) accounts require - a Unix/Linux UID that the account will map to. As users are added to the account - information database, Samba-3 will call the add user script - interface to add the account to the Samba host OS. In essence, all accounts in + a UNIX/Linux UID that the account will map to. As users are added to the account + information database, Samba will call the add user script + interface to add the account to the Samba host OS. In essence all accounts in the local SAM require a local user account.

- The second way to affect Windows SID to Unix UID mapping is via the + The second way to affect Windows SID to UNIX UID mapping is via the idmap uid, idmap gid parameters in smb.conf. Please refer to the man page for information about these parameters. These parameters are essential when mapping users from a remote SAM server. -

Account Management Tools

-Samba-3 provides two (2) tools for management of User and machine accounts. These tools are +

Mapping Common UIDs/GIDs on Distributed Machines

+ Samba-3 has a special facility that makes it possible to maintain identical UIDs and GIDs + on all servers in a distributed network. A distributed network is one where there exists + a PDC, one or more BDCs and/or one or more domain member servers. Why is this important? + This is important if files are being shared over more than one protocol (eg: NFS) and where + users are copying files across UNIX/Linux systems using tools such as rsync. +

+ The special facility is enabled using a parameter called idmap backend. + The default setting for this parameter is an empty string. Administrators should NOT set this + parameter except when an LDAP based passdb backend is in use. An example of use is: +

Example 11.1.

[global]

idmap backend = ldapsam://ldap-server.quenya.org:636

Account Management Tools

+Samba provides two (2) tools for management of User and machine accounts. These tools are called smbpasswd and pdbedit. A third tool is under development but is NOT expected to ship in time for Samba-3.0.0. The new tool will be a TCL/TK GUI tool that looks much like the MS Windows NT4 Domain User Manager - hopefully this will be announced in time for the Samba-3.0.1 release. -

The smbpasswd Command

The smbpasswd utility is a utility similar to the passwd or yppasswd programs. It maintains the two 32 byte password fields in the passdb backend. @@ -203,19 +209,19 @@ be announced in time for the Samba-3.0.1 release. if changing an NT Domain user's password).

smbpasswd can be used to: -

add user or machine accounts

delete user or machine accounts

enable user or machine accounts

disable user or machine accounts

set to NULL user passwords

manage interdomain trust accounts

add user or machine accounts
delete user or machine accounts
enable user or machine accounts
disable user or machine accounts
set to NULL user passwords
manage interdomain trust accounts

To run smbpasswd as a normal user just type:

-		$ smbpasswd
-		Old SMB password: secret
-

+$ smbpasswd
+Old SMB password: secret
+

For secret type old value here - or hit return if there was no old password -

-		New SMB Password: new secret
-		Repeat New SMB Password: new secret
-

+New SMB Password: new secret
+Repeat New SMB Password: new secret
+

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. @@ -235,10 +241,10 @@ be announced in time for the Samba-3.0.1 release.

For more details on using smbpasswd refer to the man page (the definitive reference). -

The pdbedit Command

pdbedit is a tool that can be used only by root. It is used to manage the passdb backend. pdbedit can be used to: -

add, remove or modify user accounts

listing user accounts

migrate user accounts

add, remove or modify user accounts
listing user accounts
migrate user accounts

The pdbedit tool is the only one that can manage the account security and policy settings. It is capable of all operations that smbpasswd can do as well as a super set of them. @@ -250,50 +256,60 @@ be announced in time for the Samba-3.0.1 release. The following is an example of the user account information that is stored in a tdbsam password backend. This listing was produced by running:

-		$ pdbedit -Lv met
-		Unix username:        met
-		NT username:
-		Account Flags:        [UX         ]
-		User SID:             S-1-5-21-1449123459-1407424037-3116680435-2004
-		Primary Group SID:    S-1-5-21-1449123459-1407424037-3116680435-1201
-		Full Name:            Melissa E Terpstra
-		Home Directory:       \\frodo\met\Win9Profile
-		HomeDir Drive:        H:
-		Logon Script:         scripts\logon.bat
-		Profile Path:         \\frodo\Profiles\met
-		Domain:               MIDEARTH
-		Account desc:
-		Workstations:         melbelle
-		Munged dial:
-		Logon time:           0
-		Logoff time:          Mon, 18 Jan 2038 20:14:07 GMT
-		Kickoff time:         Mon, 18 Jan 2038 20:14:07 GMT
-		Password last set:    Sat, 14 Dec 2002 14:37:03 GMT
-		Password can change:  Sat, 14 Dec 2002 14:37:03 GMT
-		Password must change: Mon, 18 Jan 2038 20:14:07 GMT
-

Password Backends

-Samba-3 offers the greatest flexibility in backend account database design of any SMB/CIFS server +$ pdbedit -Lv met +UNIX username: met +NT username: +Account Flags: [UX ] +User SID: S-1-5-21-1449123459-1407424037-3116680435-2004 +Primary Group SID: S-1-5-21-1449123459-1407424037-3116680435-1201 +Full Name: Melissa E Terpstra +Home Directory: \\frodo\met\Win9Profile +HomeDir Drive: H: +Logon Script: scripts\logon.bat +Profile Path: \\frodo\Profiles\met +Domain: MIDEARTH +Account desc: +Workstations: melbelle +Munged dial: +Logon time: 0 +Logoff time: Mon, 18 Jan 2038 20:14:07 GMT +Kickoff time: Mon, 18 Jan 2038 20:14:07 GMT +Password last set: Sat, 14 Dec 2002 14:37:03 GMT +Password can change: Sat, 14 Dec 2002 14:37:03 GMT +Password must change: Mon, 18 Jan 2038 20:14:07 GMT +

+ The pdbedit tool allows migration of authentication (account) + databases from one backend to another. For example: To migrate accounts from an + old smbpasswd database to a tdbsam + backend: +

+ Set the passdb backend = tdbsam, smbpasswd. +
+ Execute: +
```
+root# pdbedit -i smbpassed -e tdbsam
+
```
+
+ Now remove the smbpasswd from the passdb backend + configuration in smb.conf. +

Password Backends

+Samba offers the greatest flexibility in backend account database design of any SMB/CIFS server technology available today. The flexibility is immediately obvious as one begins to explore this capability.

It is possible to specify not only multiple different password backends, but even multiple backends of the same type. For example, to use two different tdbsam databases:

-[globals]
-		passdb backend = tdbsam:/etc/samba/passdb.tdb, \
-		tdbsam:/etc/samba/old-passdb.tdb, guest
-

Plain Text

passdb backend = tdbsam:/etc/samba/passdb.tdb, tdbsam:/etc/samba/old-passdb.tdb

Plain Text

Older versions of Samba retrieved user information from the unix user database and eventually some other fields from the file /etc/samba/smbpasswd or /etc/smbpasswd. When password encryption is disabled, no SMB specific data is stored at all. Instead all operations are conducted via the way that the Samba host OS will access its /etc/passwd database. eg: On Linux systems that is done via PAM. -

smbpasswd - Encrypted Password Database

- Traditionally, when configuring encrypt - passwords = yes in Samba's smb.conf file, user account +

smbpasswd - Encrypted Password Database

+ Traditionally, when configuring encrypt passwords = yes in Samba's smb.conf file, user account information such as username, LM/NT password hashes, password change times, and account flags have been stored in the smbpasswd(5) file. There are several disadvantages to this approach for sites with very large numbers of users (counted @@ -319,10 +335,10 @@ backends of the same type. For example, to use two different tdbsam databases: is commonly referred to as the samdb interface (previously this was called the passdb API, and is still so named in the Samba CVS trees).

- Samba-3 provides an enhanced set of passdb backends that overcome the deficiencies + Samba provides an enhanced set of passdb backends that overcome the deficiencies of the smbpasswd plain text database. These are tdbsam, ldapsam, and xmlsam. Of these ldapsam will be of most interest to large corporate or enterprise sites. -

tdbsam

Samba can store user and machine account data in a "TDB" (Trivial Database). +

tdbsam

Samba can store user and machine account data in a "TDB" (Trivial Database). Using this backend doesn't require any additional configuration. This backend is recommended for new installations that do not require LDAP.

@@ -330,7 +346,7 @@ backends of the same type. For example, to use two different tdbsam databases: that have 250 or more users. Additionally, tdbsam is not capable of scaling for use in sites that require PDB/BDC implementations that requires replication of the account database. Clearly, for reason of scalability, the use of ldapsam should be encouraged. -

ldapsam

There are a few points to stress that the ldapsam does not provide. The LDAP support referred to in the this documentation does not include:

A means of retrieving user account information from @@ -353,28 +369,30 @@ backends of the same type. For example, to use two different tdbsam databases: and has a working directory server already installed. For more information on LDAP architectures and Directories, please refer to the following sites.
- OpenLDAP - http://www.openldap.org/
- iPlanet Directory Server - - http://iplanet.netscape.com/directory
+ http://iplanet.netscape.com/directory

Two additional Samba resources which may prove to be helpful are

The Samba-PDC-LDAP-HOWTO maintained by Ignacio Coupeau.
The NT migration scripts from IDEALX that are geared to manage users and group in such a Samba-LDAP Domain Controller configuration. -

Supported LDAP Servers

The LDAP ldapsam code has been developed and tested using the OpenLDAP 2.0 and 2.1 server and client libraries. The same code should work with Netscape's Directory Server and client SDK. However, there are bound to be compile errors and bugs. These should not be hard to fix. Please submit fixes via Bug reporting facility. -

Schema and Relationship to the RFC 2307 posixAccount

Samba 3.0 includes the necessary schema file for OpenLDAP 2.0 in examples/LDAP/samba.schema. The sambaSamAccount objectclass is given here:

-objectclass ( 1.3.6.1.4.1.7165.2.2.3 NAME 'sambaSamAccount' SUP top AUXILIARY
-    DESC 'Samba Auxiliary Account'
-    MUST ( uid $ rid )
-    MAY  ( cn $ lmPassword $ ntPassword $ pwdLastSet $ logonTime $
-           logoffTime $ kickoffTime $ pwdCanChange $ pwdMustChange $ acctFlags $
-           displayName $ smbHome $ homeDrive $ scriptPath $ profilePath $
-           description $ userWorkstations $ primaryGroupID $ domain ))
+objectclass ( 1.3.6.1.4.1.7165.2.2.6 NAME 'sambaSamAccount' SUP top AUXILIARY
+    DESC 'Samba 3.0 Auxiliary SAM Account'
+    MUST ( uid $ sambaSID )
+    MAY  ( cn $ sambaLMPassword $ sambaNTPassword $ sambaPwdLastSet $
+          sambaLogonTime $ sambaLogoffTime $ sambaKickoffTime $
+          sambaPwdCanChange $ sambaPwdMustChange $ sambaAcctFlags $
+          displayName $ sambaHomePath $ sambaHomeDrive $ sambaLogonScript $
+          sambaProfilePath $ description $ sambaUserWorkstations $
+          sambaPrimaryGroupSID $ sambaDomainName ))

The samba.schema file has been formatted for OpenLDAP 2.0/2.1. @@ -398,7 +416,7 @@ objectclass ( 1.3.6.1.4.1.7165.2.2.3 NAME 'sambaSamAccount' SUP top AUXILIARY 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. -

OpenLDAP configuration

To include support for the sambaSamAccount object in an OpenLDAP directory server, first copy the samba.schema file to slapd's configuration directory. The samba.schema file can be found in the directory examples/LDAP @@ -432,7 +450,7 @@ include /etc/openldap/schema/nis.schema like in the following example, to speed up searches made on sambaSamAccount objectclasses (and possibly posixAccount and posixGroup as well).

+
 # Indices to maintain
 ## required by OpenLDAP
 index objectclass             eq
@@ -459,7 +477,7 @@ index   default               sub
 		Create the new index by executing:
 		

 
-./sbin/slapindex -f slapd.conf
+root# ./sbin/slapindex -f slapd.conf
 

 

 		Remember to restart slapd after making these changes:
@@ -467,34 +485,34 @@ index   default               sub
 
 root# /etc/init.d/slapd restart
 

-

Initialise the LDAP database

Before you can add accounts to the LDAP database you must create the account containers that they will be stored in. The following LDIF file should be modified to match your needs (ie: Your DNS entries, etc.).

+
 # Organization for Samba Base
-dn: dc=plainjoe,dc=org
+dn: dc=quenya,dc=org
 objectclass: dcObject
 objectclass: organization
-dc: plainjoe
-o: Terpstra Org Network
+dc: quenya
+o: Quenya Org Network
 description: The Samba-3 Network LDAP Example
 
 # Organizational Role for Directory Management
-dn: cn=Manager,dc=plainjoe,dc=org
+dn: cn=Manager,dc=quenya,dc=org
 objectclass: organizationalRole
 cn: Manager
 description: Directory Manager
 
 # Setting up container for users
-dn: ou=People,dc=plainjoe,dc=org
+dn: ou=People,dc=quenya,dc=org
 objectclass: top
 objectclass: organizationalUnit
 ou: People
 
 # Setting up admin handle for People OU
-dn: cn=admin,ou=People,dc=plainjoe,dc=org
+dn: cn=admin,ou=People,dc=quenya,dc=org
 cn: admin
 objectclass: top
 objectclass: organizationalRole
@@ -516,70 +534,39 @@ userPassword: {SSHA}c3ZM9tBaBo9autm1dL3waDS21+JSfQVz
 		
Note

 		Before Samba can access the LDAP server you need to store the LDAP admin password
 		into the Samba-3 secrets.tdb database by:
-		
-root#  smbpasswd -w secret
-		

-

Configuring Samba

+root# smbpasswd -w secret
+

Configuring Samba

The following parameters are available in smb.conf only if your version of samba was built with LDAP support. Samba automatically builds with LDAP support if the LDAP libraries are found. -

LDAP related smb.conf options: + passdb backend = ldapsam:url, + ldap ssl, + ldap admin dn, + ldap suffix, + ldap filter, + ldap machine suffix, + ldap user suffix, + ldap delete dn, + ldap passwd sync, + ldap trust ids. +

These are described in the smb.conf man page and so will not be repeated here. However, a sample smb.conf file for use with an LDAP directory could appear as

-## /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 secretpw' 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
-
-     # syntax: passdb backend = ldapsam:ldap://server-name[:port]
-     passdb backend = ldapsam:ldap://funball.samba.org, guest
-
-     # 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 suffixes by default
-     ldap user suffix = ou=People
-     ldap machine suffix = ou=Systems
-
-     # Trust unix account information in LDAP
-     #  (see the smb.conf manpage for details)
-     ldap trust ids = Yes
-
-     # 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=sambaSamAccount))"
-

Accounts and Groups management

Example 11.2. Configuration with LDAP

[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 secretpw' 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

# syntax: passdb backend = ldapsam:ldap://server-name[:port]

passdb backend = ldapsam:ldap://funball.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 suffixes by default

ldap user suffix = ou=People

ldap machine suffix = ou=Systems

# Trust unix account information in LDAP

# (see the smb.conf manpage for details)

ldap trust ids = Yes

# 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=sambaSamAccount))"

Accounts and Groups management

As users accounts are managed through the sambaSamAccount objectclass, you should modify your existing administration tools to deal with sambaSamAccount attributes.

Machines accounts are managed with the sambaSamAccount objectclass, just like users accounts. However, it's up to you to store those accounts in a different tree of your 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 + "ou=Groups,dc=quenya,dc=org" to store groups and + "ou=People,dc=quenya,dc=org" to store users. Just configure your NSS and PAM accordingly (usually, in the /etc/ldap.conf configuration file).

@@ -587,7 +574,7 @@ userPassword: {SSHA}c3ZM9tBaBo9autm1dL3waDS21+JSfQVz groups. This means that Samba makes use of the posixGroup objectclass. For now, there is no NT-like group system management (global and local groups). -

Security and sambaSamAccount

There are two important points to remember when discussing the security of sambaSamAccount entries in the directory.

Never retrieve the lmPassword or @@ -598,13 +585,13 @@ userPassword: {SSHA}c3ZM9tBaBo9autm1dL3waDS21+JSfQVz on the details of LM/NT password hashes, refer to the Account Information Database section of this chapter.
- To remedy the first security issue, the ldap ssl smb.conf parameter defaults - to require an encrypted session (ldap ssl = on) using + To remedy the first security issue, the ldap ssl smb.conf parameter defaults + to require an encrypted session (ldap ssl = on) using the default port of 636 when contacting the directory server. When using an OpenLDAP 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 - (ldap ssl = off). + (ldap ssl = off).
Note that the LDAPS protocol is deprecated in favor of the LDAPv3 StartTLS extended operation. However, the OpenLDAP library still provides support for @@ -617,84 +604,83 @@ userPassword: {SSHA}c3ZM9tBaBo9autm1dL3waDS21+JSfQVz
```
 ## 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 dn="cn=Samba Admin,ou=people,dc=quenya,dc=org" write
      by * none
 
```
-

LDAP special attributes for sambaSamAccounts

The sambaSamAccount objectclass is composed of the following attributes:

Table 11.1. Attributes in the sambaSamAccount objectclass (LDAP)

lmPassword the LANMAN password 16-byte hash stored as a character - representation of a hexadecimal string.

ntPassword the NT password hash 16-byte stored as a character - representation of a hexadecimal string.

pwdLastSet The integer time in seconds since 1970 when the - lmPassword and ntPassword attributes were last set. -

acctFlags

string of 11 characters surrounded by square brackets [] +

Table 11.1. Attributes in the sambaSamAccount objectclass (LDAP)

`sambaLMPassword`	the LANMAN password 16-byte hash stored as a character +representation of a hexadecimal string.
`sambaNTPassword`	the NT password hash 16-byte stored as a character + representation of a hexadecimal string.
`sambaPwdLastSet`	The integer time in seconds since 1970 when the + `sambaLMPassword` and `sambaNTPassword` attributes were last set. +
`sambaAcctFlags`	string of 11 characters surrounded by square brackets [] representing account flags such as U (user), W(workstation), X(no password expiration), I(Domain trust account), H(Home dir required), S(Server trust account), - and D(disabled).
`logonTime`	Integer value currently unused
`logoffTime`	Integer value currently unused
`kickoffTime`	Integer value currently unused
`pwdCanChange`	Integer value currently unused
`pwdMustChange`	Integer value currently unused
`homeDrive`	specifies the drive letter to which to map the - UNC path specified by homeDirectory. The drive letter must be specified in the form "X:" + and D(disabled).
`sambaLogonTime`	Integer value currently unused
`sambaLogoffTime`	Integer value currently unused
`sambaKickoffTime`	Integer value currently unused
`sambaPwdCanChange`	Integer value currently unused
`sambaPwdMustChange`	Integer value currently unused
`sambaHomeDrive`	specifies the drive letter to which to map the + UNC path specified by sambaHomePath. 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.
`scriptPath`	The scriptPath property specifies the path of + smb.conf(5) man page for more information.
`sambaLogonScript`	The sambaLogonScript 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.
`profilePath`	specifies a path to the user's profile. + is relative to the netlogon share. Refer to the `logon script` parameter in the + `smb.conf` man page for more information.
`sambaProfilePath`	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.
`smbHome`	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` man page for more information. -
`userWorkstation`	character string value currently unused. -
`rid`	the integer representation of the user's relative identifier - (RID).
`primaryGroupID`	the relative identifier (RID) of the primary group - of the user.
`domain`	domain the user is part of.

+ logon path parameter in the smb.conf man page for more information.

sambaHomePath The sambaHomePath property specifies the path of +the home directory for the user. The string can be null. If sambaHomeDrive is set and specifies +a drive letter, sambaHomePath 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 man page for more information. +

sambaUserWorkstations character string value currently unused. +

sambaSID The security identifier(SID) of the user. The windows equivalent of unix uid's.

sambaPrimaryGroupSID the relative identifier (RID) of the primary group + of the user.

sambaDomainName domain the user is part of.

The majority of these parameters are only used when Samba is acting as a PDC of a domain (refer to the Samba as a primary domain controller chapter for details on how to configure Samba as a Primary Domain Controller). The following four attributes are only stored with the sambaSamAccount entry if the values are non-default values: -

smbHome

scriptPath

logonPath

homeDrive

sambaHomePath
sambaLogonScript
sambaProfilePath
sambaHomeDrive

These attributes are only stored with the sambaSamAccount entry if the values are non-default values. For example, assume TASHTEGO has now been - configured as a PDC and that logon home = \\%L\%u was defined in + configured as a PDC and that logon home = \\%L\%u was defined in its smb.conf file. When a user named "becky" logons to the domain, - the logon home string is expanded to \\TASHTEGO\becky. + the logon home 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 logon home parameter is used in its place. Samba + of the logon home 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). -

Example LDIF Entries for a sambaSamAccount

The following is a working LDIF with the inclusion of the posixAccount objectclass:

-	dn: uid=guest2, ou=people,dc=plainjoe,dc=org
-	ntPassword: 878D8014606CDA29677A44EFA1353FC7
-	pwdMustChange: 2147483647
-	primaryGroupID: 1201
-	lmPassword: 552902031BEDE9EFAAD3B435B51404EE
-	pwdLastSet: 1010179124
-	logonTime: 0
+	dn: uid=guest2, ou=people,dc=quenya,dc=org
+	sambaNTPassword: 878D8014606CDA29677A44EFA1353FC7
+	sambaPwdMustChange: 2147483647
+	sambaPrimaryGroupSID: S-1-5-21-2447931902-1787058256-3961074038-513
+	sambaNTPassword: 552902031BEDE9EFAAD3B435B51404EE
+	sambaPwdLastSet: 1010179124
+	sambaLogonTime: 0
 	objectClass: sambaSamAccount
 	uid: guest2
-	kickoffTime: 2147483647
-	acctFlags: [UX         ]
-	logoffTime: 2147483647
-	rid: 19006
-	pwdCanChange: 0
+	sambaKickoffTime: 2147483647
+	sambaAcctFlags: [UX         ]
+	sambaLogoffTime: 2147483647
+	sambaSID: S-1-5-21-2447931902-1787058256-3961074038-5006
+	sambaPwdCanChange: 0

The following is an LDIF entry for using both the sambaSamAccount and posixAccount objectclasses:

-	dn: uid=gcarter, ou=people,dc=plainjoe,dc=org
-	logonTime: 0
+	dn: uid=gcarter, ou=people,dc=quenya,dc=org
+	sambaLogonTime: 0
 	displayName: Gerald Carter
-	lmPassword: 552902031BEDE9EFAAD3B435B51404EE
-	primaryGroupID: 1201
+	sambaLMPassword: 552902031BEDE9EFAAD3B435B51404EE
+	sambaPrimaryGroupSID: S-1-5-21-2447931902-1787058256-3961074038-1201
 	objectClass: posixAccount
 	objectClass: sambaSamAccount
-	acctFlags: [UX         ]
+	sambaAcctFlags: [UX         ]
 	userPassword: {crypt}BpM2ej8Rkzogo
 	uid: gcarter
 	uidNumber: 9000
@@ -702,60 +688,59 @@ access to attrs=lmPassword,ntPassword
 	loginShell: /bin/bash
 	logoffTime: 2147483647
 	gidNumber: 100
-	kickoffTime: 2147483647
-	pwdLastSet: 1010179230
-	rid: 19000
+	sambaKickoffTime: 2147483647
+	sambaPwdLastSet: 1010179230
+	sambaSID: S-1-5-21-2447931902-1787058256-3961074038-5004
 	homeDirectory: /home/tashtego/gcarter
-	pwdCanChange: 0
-	pwdMustChange: 2147483647
-	ntPassword: 878D8014606CDA29677A44EFA1353FC7
+	sambaPwdCanChange: 0
+	sambaPwdMustChange: 2147483647
+	sambaNTPassword: 878D8014606CDA29677A44EFA1353FC7

Password synchronisation

Since version 3.0 samba can update the non-samba (LDAP) password stored with an account. When using pam_ldap, this allows changing both unix and windows passwords at once. -

The ldap passwd sync options can have the following values:

yes

When the user changes his password, update +

The ldap passwd sync options can have the following values:

yes: When the user changes his password, update ntPassword, lmPassword - and the password fields.
no: Only update ntPassword and lmPassword.
only: Only update the LDAP password and let the LDAP server worry - about the other fields. This option is only available when the LDAP server supports LDAP_EXOP_X_MODIFY_PASSWD.

More information can be found in the smb.conf manpage. -

MySQL

+ and the password fields.

Only update ntPassword and lmPassword.

only

Only update the LDAP password and let the LDAP server worry about the other fields. This option is only available on some LDAP servers. ^[3]

More information can be found in the smb.conf manpage. +

MySQL

Every so often someone will come along with a great new idea. Storing of user accounts in an SQL backend is one of them. Those who want to do this are in the best position to know what the specific benefits are to them. This may sound like a cop-out, but in truth we can not attempt to document every nitty little detail why certain things of marginal utility to the bulk of Samba users might make sense to the rest. In any case, the following instructions should help the determined SQL user to implement a working system. -

Creating the database

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 examples/pdb/mysql/mysql.dump contains the correct queries to create the required tables. Use the command : -

$ mysql -uusername -hhostname -ppassword \
-databasename < /path/to/samba/examples/pdb/mysql/mysql.dump

Configuring

This plugin lacks some good documentation, but here is some short info:

Add a the following to the passdb backend variable in your smb.conf: -

-			passdb backend = [other-plugins] mysql:identifier [other-plugins]
-

+$ mysql -uusername -hhostname -ppassword \
+databasename < /path/to/samba/examples/pdb/mysql/mysql.dump
+

Configuring

This plugin lacks some good documentation, but here is some short info:

Add a the following to the passdb backend variable in your smb.conf: +

passdb backend = [other-plugins] mysql:identifier [other-plugins]

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 + specify multiple pdb_mysql.so entries in passdb backend, you also need to use different identifiers!

Additional options can be given through the smb.conf file in the [global] section.

Table 11.2. Basic smb.conf options for MySQL passdb backend

Field	Contents
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

Table 11.2. Basic smb.conf options for MySQL passdb backend

Field	Contents
mysql host	host name, defaults to 'localhost'
mysql password
mysql user	defaults to 'samba'
mysql database	defaults to 'samba'
mysql port	defaults to 3306
table	Name of the table containing users

Warning

Since the password for the MySQL user is stored in the - smb.conf file, you should make the the smb.conf file + smb.conf file, you should make the smb.conf file readable only to the user that runs Samba This is considered a security bug and will be fixed soon.

Names of the columns in this table (I've added column types those columns should have first):

Table 11.3. MySQL field names for MySQL passdb backend

Field	Type	Contents
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

Table 11.3. MySQL field names for MySQL passdb backend

Field	Type	Contents
logon time column	int(9)
logoff time column	int(9)
kickoff time column	int(9)
pass last set time column	int(9)
pass can change time column	int(9)
pass must change time column	int(9)
username column	varchar(255)	unix username
domain column	varchar(255)	NT domain user is part of
nt username column	varchar(255)	NT username
fullname column	varchar(255)	Full name of user
home dir column	varchar(255)	UNIX homedir path
dir drive column	varchar(2)	Directory drive path (eg: 'H:')
logon script column	varchar(255)	Batch file to run on client side when logging on
profile path column	varchar(255)	Path of profile
acct desc column	varchar(255)	Some ASCII NT user data
workstations column	varchar(255)	Workstations user can logon to (or NULL for all)
unknown string column	varchar(255)	unknown string
munged dial column	varchar(255)	?
user sid column	varchar(255)	NT user SID
group sid column	varchar(255)	NT group ID
lanman pass column	varchar(255)	encrypted lanman password
nt pass column	varchar(255)	encrypted nt passwd
plain pass column	varchar(255)	plaintext password
acct control column	int(9)	nt user data
unknown 3 column	int(9)	unknown
logon divs column	int(9)	?
hours len column	int(9)	?
unknown 5 column	int(9)	unknown
unknown 6 column	int(9)	unknown

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. -

Using plaintext passwords or encrypted password

I strongly discourage the use of plaintext passwords, however, you can use them:

If you would like to use plaintext passwords, set @@ -765,7 +750,7 @@ access to attrs=lmPassword,ntPassword

If you use encrypted passwords, set the 'identifier:plain pass column' to 'NULL' (without the quotes). This is the default. -

Getting non-column data from the table

It is possible to have not all data in the database and making some 'constant'.

For example, you can set 'identifier:fullname column' to : @@ -780,33 +765,21 @@ access to attrs=lmPassword,ntPassword

To import data, use: $ pdbedit -i xml:filename -

Common Errors

Users can not logon - Users not in Samba SAM

- People forget to put their users in their backend and then complain Samba won't authorize them. -

Users are being added to the wrong backend database

Common Errors

Users can not logon

“I've installed samba, but now I can't log on with my unix account!”

Make sure your user has been added to the current samba passdb backend. Read the section Account Management Tools for details.

Users being added to wrong backend database

A few complaints have been received from users that just moved to Samba-3. The following smb.conf file entries were causing problems, new accounts were being added to the old smbpasswd file, not to the tdbsam passdb.tdb file:

-	[globals]
-		...
-		passdb backend = smbpasswd, tdbsam, guest
-		...
-

[global]

...

passdb backend = smbpasswd, tdbsam

...

Samba will add new accounts to the first entry in the passdb backend parameter entry. If you want to update to the tdbsam, then change the entry to:

-	[globals]
-		...
-		passdb backend = tdbsam, smbpasswd, guest
-		...
-

auth methods does not work

- If you explicitly set an 'auth methods' parameter, guest must be specified as the first - entry on the line. Eg: auth methods = guest sam. +

[globals]

...

passdb backend = tdbsam, smbpasswd

...

auth methods does not work

+ If you explicitly set an auth methods parameter, guest must be specified as the first + entry on the line. Eg: auth methods = guest sam.

- This is the exact opposite of the requirement for the passdb backed + This is the exact opposite of the requirement for the passdb backend option, where it must be the LAST parameter on the line. -

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^[3]Only when the LDAP server supports LDAP_EXOP_X_MODIFY_PASSWD