Cisco Security Appliance Command Line Configuration Guide, Version 8.0 - Configuring an External Server for Security Appliance User Authorization [Cisco ASA 5500 Series Adaptive Security Appliances]

Table Of Contents

Configuring an External Server for Authorization and Authentication

Understanding Policy Enforcement of Permissions and Attributes

Configuring an External LDAP Server

Organizing the Security Appliance for LDAP Operations

Searching the Hierarchy

Binding the Security Appliance to the LDAP Server

Login DN Example for Active Directory

Defining the Security Appliance LDAP Configuration

Supported Cisco Attributes for LDAP Authorization

Cisco-AV-Pair Attribute Syntax

Active Directory/LDAP VPN Remote Access Authorization Use Cases

User-Based Attributes Policy Enforcement

Placing LDAP users in a specific Group-Policy

Enforcing Static IP Address Assignment for AnyConnect Tunnels

Enforcing Dial-in Allow or Deny Access

Enforcing Logon Hours and Time-of-Day Rules

Configuring an External RADIUS Server

Reviewing the RADIUS Configuration Procedure

Security Appliance RADIUS Authorization Attributes

Configuring an External TACACS+ Server

Configuring an External Server for Authorization and Authentication

This appendix describes how to configure an external LDAP, RADIUS, or TACACS+ server to support AAA on the security appliance. Before you configure the security appliance to use an external server, you must configure the server with the correct security appliance authorization attributes and, from a subset of these attributes, assign specific permissions to individual users.

This appendix includes the following sections:

•Understanding Policy Enforcement of Permissions and Attributes

•Configuring an External LDAP Server

•Configuring an External RADIUS Server

•Configuring an External TACACS+ Server

Understanding Policy Enforcement of Permissions and Attributes

The security appliance supports several methods of applying user authorization attributes (also called user entitlements or permissions) to VPN connections. You can configure the security appliance to obtain user attributes from a Dynamic Access Policy (DAP) on the security appliance, from an external authentication and/or authorization AAA server (RADIUS or LDAP), from a group policy on the security appliance, or from all three.

If the security appliance receives attributes from all sources, the attributes are evaluated, merged, and applied to the user policy. If there are conflicts between attributes coming from the DAP, the AAA server, or the group policy, those attributes obtained from the DAP always take precedence.

The security appliance applies attributes in the following order (also illustrated in Figure D-1:

1. DAP attributes on the security appliance—Introduced in Version 8.0, take precedence over all others. If you set a bookmark/URL list in DAP, it overrides a bookmark/URL list set in the group policy.

2. User attributes on the AAA server—The server returns these after successful user authentication and/or authorization. Do not confuse these with attributes that are set for individual users in the local AAA database on the security appliance (User Accounts in ASDM).

3. Group policy configured on the security appliance—If a RADIUS server returns the value of the RADIUS CLASS attribute IETF-Class-25 (OU=<group-policy>) for the user, the security appliance places the user in the group policy of the same name and enforces any attributes in the group policy that are not returned by the server. For LDAP servers, any attribute name can be used to set the group policy for the session. The LDAP attribute map you configure on the security appliance maps the LDAP attribute to the Cisco attribute IETF-Radius-Class.

4. Group policy assigned by the Connection Profile (called tunnel-group in CLI)—The Connection Profile has the preliminary settings for the connection, and includes a default group policy applied to the user before authentication. All users connecting to the security appliance initially belong to this group which provides any attributes that are missing from the DAP, user attributes returned by the server, or the group policy assigned to the user.

5. Default group policy assigned by the security appliance (DfltGrpPolicy)—System default attributes provide any values that are missing from the DAP, user attributes, group policy, or connection profile.

Figure D-1 Policy Enforcement Flow

Configuring an External LDAP Server

The VPN 3000 Concentrator and the ASA/PIX 7.0 required a Cisco LDAP schema for authorization operations. Beginning with Version 7.1.x, the security appliance performs authentication and authorization, using the native LDAP schema, and the Cisco schema is no longer needed.

You configure authorization (permission policy) using an LDAP attribute map. For examples, see
Active Directory/LDAP VPN Remote Access Authorization Use Cases.

This section describes the structure, schema, and attributes of an LDAP server. It includes the following topics:

•Organizing the Security Appliance for LDAP Operations

•Defining the Security Appliance LDAP Configuration

•Active Directory/LDAP VPN Remote Access Authorization Use Cases

The specific steps of these processes vary, depending on which type of LDAP server you are using.

Note For more information on the LDAP protocol, see RFCs 1777, 2251, and 2849.

Organizing the Security Appliance for LDAP Operations

This section describes how to perform searches within the LDAP hierarchy and authenticated binding to the LDAP server on the security appliance. It includes the following topics:

•Searching the Hierarchy

•Binding the Security Appliance to the LDAP Server

•Login DN Example for Active Directory

Your LDAP configuration should reflect the logical hierarchy of your organization. For example, suppose an employee at your company, Example Corporation, is named Terry. Terry works in the Engineering group. Your LDAP hierarchy could have one or many levels. You might decide to set up a shallow, single-level hierarchy in which Terry is considered a member of Example Corporation. Or, you could set up a multi-level hierarchy in which Terry is considered to be a member of the department Engineering, which is a member of an organizational unit called People, which is itself a member of Example Corporation. See Figure D-2 for an example of this multi-level hierarchy.

A multi-level hierarchy has more granularity, but a single level hierarchy is quicker to search.

Figure D-2 A Multi-Level LDAP Hierarchy

Searching the Hierarchy

The security appliance lets you tailor the search within the LDAP hierarchy. You configure the following three fields on the security appliance to define where in the LDAP hierarchy your search begins, the extent, and the type of information it is looking for. Together these fields allow you to limit the search of the hierarchy to only the part of the tree that contains the user permissions.

•LDAP Base DN defines where in the LDAP hierarchy the server should begin searching for user information when it receives an authorization request from the security appliance.

•Search Scope defines the extent of the search in the LDAP hierarchy. The search proceeds this many levels in the hierarchy below the LDAP Base DN. You can choose to have the server search only the level immediately below, or it can search the entire subtree. A single level search is quicker, but a subtree search is more extensive.

•Naming Attribute(s) defines the RDN that uniquely identifies an entry in the LDAP server. Common naming attributes can include cn (Common Name), sAMAccountName, and userPrincipalName.

Figure D-2 shows a possible LDAP hierarchy for Example Corporation. Given this hierarchy, you could define your search in different ways. Table D-1 shows two possible search configurations.

In the first example configuration, when Terry establishes the IPSec tunnel with LDAP authorization required, the security appliance sends a search request to the LDAP server indicating it should search for Terry in the Engineering group. This search is quick.

In the second example configuration, the security appliance sends a search request indicating the server should search for Terry within Example Corporation. This search takes longer.

Table D-1 Example Search Configurations

#

LDAP Base DN

Search Scope

Naming Attribute

Result

1

group= Engineering,ou=People,dc=ExampleCorporation, dc=com

One Level

cn=Terry

Quicker search

2

dc=ExampleCorporation,dc=com

Subtree

cn=Terry

Longer search

Binding the Security Appliance to the LDAP Server

Some LDAP servers (including the Microsoft Active Directory server) require the security appliance to establish a handshake via authenticated binding before they accept requests for any other LDAP operations. The security appliance identifies itself for authenticated binding by attaching a Login DN field to the user authentication request. The Login DN field defines the authentication characteristics of the security appliance; these characteristics should correspond to those of a user with administrative privileges. An example Login DN field could be: cn=Administrator, cn=users, ou=people, dc=example, dc=com.

Note As an LDAP client, the security appliance does not support sending anonymous binds or requests.

Login DN Example for Active Directory

The Login DN is a username on the LDAP server that the security appliance uses to establish a trust between itself (the LDAP client) and the LDAP server during the Bind exchange, before a user search can take place.

For VPN authentication/authorization operations, and beginning with version 8.0.4 for retrieval of AD Groups, (which are read operations only when password-management changes are not required), the you can use the Login DN with fewer privileges. For example, the Login DN can be a user who is a memberOf the Domain Users group.

For VPN password-management changes, the Login DN must have Account Operators privileges.

In either of these cases, Super-user level privileges are not required for the Login/Bind DN. Refer to your LDAP Administrator guide for specific Login DN requirements.

Defining the Security Appliance LDAP Configuration

This section describes how to define the LDAP AV-pair attribute syntax. It includes the following topics:

•Supported Cisco Attributes for LDAP Authorization

•Cisco-AV-Pair Attribute Syntax

Note The security appliance enforces the LDAP attributes based on attribute name, not numeric ID. RADIUS attributes, on the other hand, are enforced by numeric ID, not by name.

Authorization refers to the process of enforcing permissions or attributes. An LDAP server defined as an authentication or authorization server will enforce permissions or attributes if they are configured.

For software Version 7.0, LDAP attributes include the cVPN3000 prefix. For Version 7.1 and later, this prefix was removed.

Supported Cisco Attributes for LDAP Authorization

This section provides a complete list of attributes (Table D-2) for the ASA 5500, VPN 3000, and PIX 500 series security appliances. The table includes attribute support information for the VPN 3000 and PIX 500 series to assist you configure networks with a mixture of these security appliances.

Table D-2 Security Appliance Supported Cisco Attributes for LDAP Authorization

Attribute Name/

VPN 3000

ASA

PIX

Syntax/
Type

Single or Multi-Valued

Possible Values

Access-Hours

Y

Y

Y

String

Single

Name of the time-range
(for example, Business-Hours)

Allow-Network-Extension- Mode

Y

Y

Y

Boolean

Single

0 = Disabled
1 = Enabled

Authenticated-User-Idle- Timeout

Y

Y

Y

Integer

Single

1 - 35791394 minutes

Authorization-Required

Y

Integer

Single

0 = No
1 = Yes

Authorization-Type

Y

Integer

Single

0 = None
1 = RADIUS
2 = LDAP

Auth-Service-Type

Banner1

Y

Y

Y

String

Single

Banner string

Banner2

Y

Y

Y

String

Single

Banner string

Cisco-AV-Pair

Y

Y

Y

String

Multi

An octet string in the following format:

[Prefix] [Action] [Protocol] [Source] [Source Wildcard Mask] [Destination] [Destination Wildcard Mask] [Established] [Log] [Operator] [Port]

For more information, see "Cisco-AV-Pair Attribute Syntax."

Cisco-IP-Phone-Bypass

Y

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

Cisco-LEAP-Bypass

Y

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

Client-Intercept-DHCP- Configure-Msg

Y

Y

Y

Boolean

Single

0 = Disabled
1 = Enabled

Client-Type-Version-Limiting

Y

Y

Y

String

Single

IPSec VPN client version number string

Confidence-Interval

Y

Y

Y

Integer

Single

10 - 300 seconds

DHCP-Network-Scope

Y

Y

Y

String

Single

IP address

DN-Field

Y

Y

Y

String

Single

Possible values: UID, OU, O, CN, L, SP, C, EA, T, N, GN, SN, I, GENQ, DNQ, SER, use-entire-name.

Firewall-ACL-In

Y

Y

String

Single

Access list ID

Firewall-ACL-Out

Y

Y

String

Single

Access list ID

IE-Proxy-Bypass-Local

Boolean

Single

0=Disabled
1=Enabled

IE-Proxy-Exception-List

String

Single

A list of DNS domains. Entries must be separated by the new line character sequence (\n).

IE-Proxy-Method

Y

Y

Y

Integer

Single

1 = Do not modify proxy settings
2 = Do not use proxy
3 = Auto detect
4 = Use security appliance setting

IE-Proxy-Server

Y

Y

Y

Integer

Single

IP Address

IETF-Radius-Class

Y

Y

Y

Single

Sets the group policy for the remote access VPN session

IETF-Radius-Filter-Id

Y

Y

Y

String

Single

access list name that is defined on the security appliance

IETF-Radius-Framed-IP-Address

Y

Y

Y

String

Single

An IP address

IETF-Radius-Framed-IP-Netmask

Y

Y

Y

String

Single

An IP address mask

IETF-Radius-Idle-Timeout

Y

Y

Y

Integer

Single

minutes

IETF-Radius-Service-Type

Y

Y

Y

Integer

Single

IETF-Radius-Session-Timeout

Y

Y

Y

Integer

Single

IKE-Keep-Alives

Y

Y

Y

Boolean

Single

0 = Disabled
1 = Enabled

IPSec-Allow-Passwd-Store

Y

Y

Y

Boolean

Single

0 = Disabled
1 = Enabled

IPSec-Authentication

Y

Y

Y

Integer

Single

0 = None
1 = RADIUS
2 = LDAP (authorization only)
3 = NT Domain
4 = SDI (RSA)
5 = Internal
6 = RADIUS with Expiry
7 = Kerberos/Active Directory

IPSec-Auth-On-Rekey

Y

Y

Y

Boolean

Single

0 = Disabled
1 = Enabled

IPSec-Backup-Server-List

Y

Y

Y

String

Single

Server Addresses (space delimited)

IPSec-Backup-Servers

Y

Y

Y

String

Single

1 = Use Client-Configured list
2 = Disabled and clear client list
3 = Use Backup Server list

IPSec-Client-Firewall-Filter- Name

Y

String

Single

Specifies the name of the filter to be pushed to the client as firewall policy.

IPSec-Client-Firewall-Filter- Optional

Y

Y

Y

Integer

Single

0 = Required
1 = Optional

IPSec-Default-Domain

Y

Y

Y

String

Single

Specifies the single default domain name to send to the client (1 - 255 characters).

IPSec-IKE-Peer-ID-Check

Y

Y

Y

Integer

Single

1 = Required
2 = If supported by peer certificate
3 = Do not check

IPSec-IP-Compression

Y

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

IPSec-Mode-Config

Y

Y

Y

Boolean

Single

0 = Disabled
1 = Enabled

IPSec-Over-UDP

Y

Y

Y

Boolean

Single

0 = Disabled
1 = Enabled

IPSec-Over-UDP-Port

Y

Y

Y

Integer

Single

4001 - 49151; default = 10000

IPSec-Required-Client-Firewall-
Capability

Y

Y

Y

Integer

Single

0 = None
1 = Policy defined by remote FW Are-You-There (AYT)
2 = Policy pushed CPP
4 = Policy from server

IPSec-Sec-Association

Y

String

Single

Name of the security association

IPSec-Split-DNS-Names

Y

Y

Y

String

Single

Specifies the list of secondary domain names to send to the client (1 - 255 characters).

IPSec-Split-Tunneling-Policy

Y

Y

Y

Integer

Single

0 = Tunnel everything
1 = Split tunneling
2 = Local LAN permitted

IPSec-Split-Tunnel-List

Y

Y

Y

String

Single

Specifies the name of the network or access list that describes the split tunnel inclusion list.

IPSec-Tunnel-Type

Y

Y

Y

Integer

Single

1 = LAN-to-LAN
2 = Remote access

IPSec-User-Group-Lock

Y

Boolean

Single

0 = Disabled
1 = Enabled

L2TP-Encryption

Y

Integer

Single

Bitmap:

1 = Encryption required
2 = 40 bit
4 = 128 bits
8 = Stateless-Req
15 = 40/128-Encr/Stateless-Req

L2TP-MPPC-Compression

Y

Integer

Single

0 = Disabled
1 = Enabled

MS-Client-Subnet-Mask

Y

Y

Y

String

Single

An IP address

PFS-Required

Y

Y

Y

Boolean

Single

0 = No
1 = Yes

Port-Forwarding-Name

Y

Y

String

Single

Name string (for example, "Corporate-Apps")

PPTP-Encryption

Y

Integer

Single

Bitmap:

1 = Encryption required
2 = 40 bits
4 = 128 bits
8 = Stateless-Required

Example:
15 = 40/128-Encr/Stateless-Req

PPTP-MPPC-Compression

Y

Integer

Single

0 = Disabled
1 = Enabled

Primary-DNS

Y

Y

Y

String

Single

An IP address

Primary-WINS

Y

Y

Y

String

Single

An IP address

Privilege-Level

Required-Client- Firewall-Vendor-Code

Y

Y

Y

Integer

Single

1 = Cisco Systems (with Cisco Integrated Client)
2 = Zone Labs
3 = NetworkICE
4 = Sygate
5 = Cisco Systems (with Cisco Intrusion Prevention Security Agent)

Required-Client-Firewall- Description

Y

Y

Y

String

Single

String

Required-Client-Firewall- Product-Code

Y

Y

Y

Integer

Single

Cisco Systems Products:

1 = Cisco Intrusion Prevention Security Agent or Cisco Integrated Client (CIC)

Zone Labs Products:

1 = Zone Alarm
2 = Zone AlarmPro
3 = Zone Labs Integrity

NetworkICE Product:

1 = BlackIce Defender/Agent

Sygate Products:

1 = Personal Firewall
2 = Personal Firewall Pro
3 = Security Agent

Require-HW-Client-Auth

Y

Y

Y

Boolean

Single

0 = Disabled
1 = Enabled

Require-Individual-User-Auth

Y

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

Secondary-DNS

Y

Y

Y

String

Single

An IP address

Secondary-WINS

Y

Y

Y

String

Single

An IP address

SEP-Card-Assignment

Integer

Single

Not used

Simultaneous-Logins

Y

Y

Y

Integer

Single

0-2147483647

Strip-Realm

Y

Y

Y

Boolean

Single

0 = Disabled
1 = Enabled

TACACS-Authtype

Y

Y

Y

Interger

Single

TACACS-Privilege-Level

Y

Y

Y

Interger

Single

Tunnel-Group-Lock

Y

Y

String

Single

Name of the tunnel group or "none"

Tunneling-Protocols

Y

Y

Y

Integer

Single

1 = PPTP
2 = L2TP
4 = IPSec
8 = L2TP/IPSec
16 = WebVPN.
8 and 4 are mutually exclusive
(0 - 11, 16 - 27 are legal values)

Use-Client-Address

Y

Boolean

Single

0 = Disabled
1 = Enabled

User-Auth-Server-Name

Y

String

Single

IP address or hostname

User-Auth-Server-Port

Y

Integer

Single

Port number for server protocol

User-Auth-Server-Secret

Y

String

Single

Server password

WebVPN-ACL-Filters

Y

String

Single

Access-List name

WebVPN-Apply-ACL-Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-Citrix-Support-Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-Content-Filter- Parameters

Y

Y

Integer

Single

1 = Java & ActiveX
2 = Java scripts
4 = Images
8 = Cookies in images

Add the values to filter multiple parameters. For example: enter 10 to filter both Java scripts and cookies. (10 = 2 + 8)

WebVPN-Enable-functions

Integer

Single

Not used - deprecated

WebVPN-Exchange-Server- Address

String

Single

Not used - deprecated

WebVPN-Exchange-Server- NETBIOS-Name

String

Single

Not used - deprecated

WebVPN-File-Access-Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-File-Server-Browsing-
Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-File-Server-Entry- Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-Forwarded-Ports

Y

String

Single

Port-Forward list name

WebVPN-Homepage

Y

Y

String

Single

A URL such as http://example-portal.com.

WebVPN-Macro-Substitution-
Value1

Y

Y

String

Single

WebVPN-Macro-Substitution-
Value2

Y

Y

String

Single

WebVPN-Port-Forwarding- Auto-Download-Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-Port-Forwarding- Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-Port-Forwarding- Exchange-Proxy-Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-Port-Forwarding- HTTP-Proxy-Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-Single-Sign-On- Server-Name

Y

String

Single

Name of the SSO Server (1 - 31 characters).

WebVPN-SVC-Client-DPD

Y

Y

Integer

Single

0 = Disabled
n = Dead Peer Detection value in seconds (30 - 3600)

WebVPN-SVC-Compression

Y

Y

Integer

Single

0 = None
1 = Deflate Compression

WebVPN-SVC-Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-SVC-Gateway-DPD

Y

Y

Integer

Single

0 = Disabled
n = Dead Peer Detection value in seconds (30 - 3600)

WebVPN-SVC-Keepalive

Y

Y

Integer

Single

0 = Disabled
n = Keepalive value in seconds (15 - 600)

WebVPN-SVC-Keep-Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-SVC-Rekey-Method

Y

Y

Integer

Single

0 = None
1 = SSL
2 = New tunnel
3 = Any (sets to SSL)

WebVPN-SVC-Rekey-Period

Y

Y

Integer

Single

0 = Disabled
n = Retry period in minutes
(4 - 10080)

WebVPN-SVC-Required-Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-URL-Entry-Enable

Y

Y

Integer

Single

0 = Disabled
1 = Enabled

WebVPN-URL-List

Y

String

Single

URL-list name

Cisco-AV-Pair Attribute Syntax

The syntax of each Cisco-AV-Pair rule is as follows:

[Prefix] [Action] [Protocol] [Source] [Source Wildcard Mask] [Destination] [Destination Wildcard Mask] [Established] [Log] [Operator] [Port]

Table D-3 describes the syntax rules.

Table D-3 AV-Pair Attribute Syntax Rules

Field

Description

Prefix

A unique identifier for the AV pair. For example: ip:inacl#1= (for standard access lists) or webvpn:inacl# (for clientless SSL VPN access lists). This field only appears when the filter has been sent as an AV pair.

Action

Action to perform if rule matches: deny, permit.

Protocol

Number or name of an IP protocol. Either an integer in the range 0 - 255 or one of the following keywords: icmp, igmp, ip, tcp, udp.

Source

Network or host that sends the packet. Specify it as an IP address, a hostname, or the keyword "any." If using an IP address, the source wildcard mask must follow.

Source Wildcard Mask

The wildcard mask that applies to the source address.

Destination

Network or host that receives the packet. Specify as an IP address, a hostname, or the keyword "any." If using an IP address, the source wildcard mask must follow.

Destination Wildcard Mask

The wildcard mask that applies to the destination address.

Log

Generates a FILTER log message. You must use this keyword to generate events of severity level 9.

Operator

Logic operators: greater than, less than, equal to, not equal to.

Port

The number of a TCP or UDP port in the range 0 - 65535.

For example:
ip:inacl#1=deny ip 10.155.10.0 0.0.0.255 10.159.2.0 0.0.0.255 log 
ip:inacl#2=permit TCP any host 10.160.0.1 eq 80 log 
webvpn:inacl#1=permit url http://www.website.com
webvpn:inacl#2=deny smtp any host 10.1.3.5
webvpn:inacl#3=permit url cifs://mar_server/peopleshare1
Note Use Cisco-AV pair entries with the ip:inacl# prefix to enforce access lists for remote IPSec and SSL VPN Client (SVC) tunnels.

Use Cisco-AV pair entries with the webvpn:inacl# prefix to enforce access lists for SSL VPN clientless (browser-mode) tunnels.

Table D-4 lists the tokens for the Cisco-AV-pair attribute:

Table D-4 Security Appliance-Supported Tokens

Token

Syntax Field

Description

ip:inacl#Num=

N/A (Identifier)

(Where Num is a unique integer.) Starts all AV pair access control lists. Enforces access lists for remote IPSec and SSL VPN (SVC) tunnels.

webvpn:inacl#Num=

N/A (Identifier)

(Where Num is a unique integer.) Starts all clientless SSL AV pair access control lists. Enforces access lists for clientless (browser-mode) tunnels.

deny

Action

Denies action. (Default)

permit

Action

Allows action.

icmp

Protocol

Internet Control Message Protocol (ICMP)

1

Protocol

Internet Control Message Protocol (ICMP)

IP

Protocol

Internet Protocol (IP)

0

Protocol

Internet Protocol (IP)

TCP

Protocol

Transmission Control Protocol (TCP)

6

Protocol

Transmission Control Protocol (TCP)

UDP

Protocol

User Datagram Protocol (UDP)

17

Protocol

User Datagram Protocol (UDP)

any

Hostname

Rule applies to any host.

host

Hostname

Any alpha-numeric string that denotes a hostname.

log

Log

When the event is hit, a filter log message appears. (Same as permit and log or deny and log.)

lt

Operator

Less than value

gt

Operator

Greater than value

eq

Operator

Equal to value

neq

Operator

Not equal to value

range

Operator

Inclusive range. Should be followed by two values.

Active Directory/LDAP VPN Remote Access Authorization Use Cases

This section presents example procedures for configuring authentication and authorization on the security appliance using the Microsoft Active Directory server. It includes the following use cases:

•User-Based Attributes Policy Enforcement

•Placing LDAP users in a specific Group-Policy

•Enforcing Static IP Address Assignment for AnyConnect Tunnels

•Enforcing Dial-in Allow or Deny Access

•Enforcing Logon Hours and Time-of-Day Rules

Other configuration examples available on Cisco.com include the following TechNotes:

•ASA/PIX: Mapping VPN Clients to VPN Group Policies Through LDAP Configuration Example at:

http://www.cisco.com/en/US/products/ps6120/products_configuration_example09186a008089149d.shtml

•PIX/ASA 8.0: Use LDAP Authentication to Assign a Group Policy at Login at:

http://www.cisco.com/en/US/partner/products/ps6120/products_configuration_example09186a00808d1a7c.shtml

User-Based Attributes Policy Enforcement

Any standard LDAP attribute can be mapped to a well-known Vendor Specific Attribute (VSA) Likewise, one or more LDAP attribute(s) can be mapped to one or more Cisco LDAP attributes.

In this use case we configure the security appliance to enforce a simple banner for a user configured on an AD LDAP server. For this case, on the server, we use the Office field in the General tab to enter the banner text. This field uses the attribute named physicalDeliveryOfficeName. On the security appliance, we create an attribute map that maps physicalDeliveryOfficeName to the Cisco attribute Banner1. During authentication, the security appliance retrieves the value of physicalDeliveryOfficeName from the server, maps the value to the Cisco attribute Banner1, and displays the banner to the user.

This case applies to any connection type, including the IPSec VPN client, AnyConnect SSL VPN client, or clientless SSL VPN. For the purposes of this case, User1 is connecting through a clientless SSL VPN connection.

Step 1 Configure the attributes for a user on the AD/LDAP Server.

Right-click a user. The properties window displays (Figure D-3). Click the General tab and enter some banner text in the Office field. The Office field uses the AD/LDAP attribute physicalDeliveryOfficeName.

Figure D-3 Figure 3 LDAP User configuration

Step 2 Create an LDAP attribute map on the security appliance:

The following example creates the map Banner, and maps the AD/LDAP attribute physicalDeliveryOfficeName to the Cisco attribute Banner1:
hostname(config)# ldap attribute-map Banner
hostname(config-ldap-attribute-map)# map-name physicalDeliveryOfficeName Banner1
Step 3 Associate the LDAP attribute map to the AAA server.

The following example enters the aaa server host configuration more for the host 3.3.3.4, in the AAA server group MS_LDAP, and associates the attribute map Banner that you created in step 2:
hostname(config)# aaa-server MS_LDAP host 3.3.3.4
hostname(config-aaa-server-host)# ldap-attribute-map Banner
Step 4 Test the banner enforcement.

This example shows a clientless SSL connection and the banner enforced through the attribute map after the user authenticates (Figure D-4).

Figure D-4 Banner Displayed

Placing LDAP users in a specific Group-Policy

In this case we authenticate User1 on the AD LDAP server to a specific group policy on the security appliance. On the server, we use the Department field of the Organization tab to enter the name of the group policy. Then we create an attribute map and map Department to the Cisco attribute IETF-Radius-Class. During authentication, the security appliance retrieves the value of Department from the server, maps the value to the IETF-Radius-Class, and places User1 in the group policy.

This case applies to any connection type, including the IPSec VPN client, AnyConnect SSL VPN client, or clientless SSL VPN. For the purposes of this case, user1 is connecting through a clientless SSL VPN connection.

Step 1 Configure the attributes for the user on the AD LDAP Server.

Right-click the user. The Properties window displays (Figure D-5). Click the Organization tab and enter Group-Policy-1 in the Department field.

Figure D-5 AD LDAP Department attribute

Step 2 Define an attribute map for the LDAP configuration shown in Step 1.

In this case we map the AD attribute Department to the Cisco attribute IETF-Radius-Class. For example:
hostname(config)# ldap attribute-map group_policy
hostname(config-ldap-attribute-map)# map-name Department IETF-Radius-Class
Step 3 Associate the LDAP attribute map to the AAA server.

The following example enters the aaa server host configuration mode for the host 3.3.3.4, in the AAA server group MS_LDAP, and associates the attribute map group_policy that you created in step 2:
hostname(config)# aaa-server MS_LDAP host 3.3.3.4
hostname(config-aaa-server-host)# ldap-attribute-map group_policy