IPv6 Access Control Lists

Access lists determine what traffic is blocked and what traffic is forwarded at device interfaces and allow filtering of traffic based on source and destination addresses, and inbound and outbound traffic to a specific interface. Standard IPv6 ACL functionality was extended to support traffic filtering based on IPv6 option headers and optional, upper-layer protocol type information for finer granularity of control. Standard IPv6 ACL functionality was extended to support traffic filtering based on IPv6 option headers and optional, upper-layer protocol type information for finer granularity of control.

This module describes how to configure IPv6 traffic filtering and to control access to virtual terminal lines.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Information About IPv6 Access Control Lists

Access Control Lists for IPv6 Traffic Filtering

The standard access control list (ACL) functionality in IPv6 is similar to the standard ACLs in IPv4. Access lists determine the type of traffic that is blocked or forwarded at device interfaces. Access lists allow the filtering of inbound and outbound traffic at specific interfaces based on source and destination addresses. At the end of each access list is an implicit deny statement.

Use the ipv6 access-list command to define IPv6 ACLs and the permit and deny commands to set the deny and permit conditions, respectively.

IPv6 extended ACLs augment the standard IPv6 ACL functionality to support traffic filtering based on IPv6 option headers and optional, upper-layer protocol type information.

How to Configure IPv6 Access Control Lists

Configuring IPv6 Traffic Filtering

Creating and Configuring an IPv6 ACL for Traffic Filtering

This section describes how to configure your networking devices to filter traffic, function as a firewall, or detect potential viruses.

Before You Begin

Note
  • Each IPv6 ACL contains implicit permit rules to enable IPv6 neighbor discovery. These rules can be overridden by the user by placing a deny ipv6 any any statement within an ACL. The IPv6 neighbor discovery process makes use of the IPv6 network layer service; therefore, by default, IPv6 ACLs implicitly allow IPv6 neighbor discovery packets to be sent and received on an interface. In IPv4, the Address Resolution Protocol (ARP), which is equivalent to the IPv6 neighbor discovery process, makes use of a separate data link layer protocol; therefore, by default, IPv4 ACLs implicitly allow ARP packets to be sent and received on an interface.
  • Time-based and reflexive ACLs are not supported for IPv4 or IPv6 on the Cisco 12000 series platform. The reflect, timeout, and time-range keywords of the permit command in IPv6 are excluded on the Cisco 12000 series.
>
SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    ipv6 access-list access-list-name

    4.    Do one of the following:

    • permit protocol {source-ipv6-prefix / prefix-length | any | host source-ipv6-address | auth} [operator [port-number]] {destination-ipv6-prefix / prefix-length| any | host destination-ipv6-address| auth} [operator [port-number]] [dest-option-type [doh-number| doh-type]] [dscp value] [flow-label value] [fragments] [log] [log-input] [mobility] [mobility-type [mh-number | mh-type]] [reflect name [timeout value]] [routing] [routing-type routing-number] [sequence value] [time-range name]
    • deny protocol {source-ipv6-prefix / prefix-length | any | host source-ipv6-address | auth} [operator port-number]] {destination-ipv6-prefix/prefix-length | any | host destination-ipv6-address | auth} [operator [port-number]] [dest-option-type [doh-number | doh-type]] [dscp value] [flow-label value] [fragments] [log] [log-input] [mobility] [mobility-type [mh-number | mh-type]] [routing] [routing-type routing-number] [sequence value] [time-range name] [undetermined-transport]


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example:
    Router> enable
     

    Enables privileged EXEC mode.

    • Enter your password if prompted.
     
    Step 2 configure terminal


    Example:
    Router# configure terminal
     

    Enters global configuration mode.

     
    Step 3 ipv6 access-list access-list-name


    Example:
    Router(config)# ipv6 access-list outbound
     

    Defines an IPv6 ACL, and enters IPv6 access list configuration mode.

    • The access-list name argument specifies the name of the IPv6 ACL. IPv6 ACL names cannot contain a space or quotation mark, or begin with a numeral.
     
    Step 4Do one of the following:
    • permit protocol {source-ipv6-prefix / prefix-length | any | host source-ipv6-address | auth} [operator [port-number]] {destination-ipv6-prefix / prefix-length| any | host destination-ipv6-address| auth} [operator [port-number]] [dest-option-type [doh-number| doh-type]] [dscp value] [flow-label value] [fragments] [log] [log-input] [mobility] [mobility-type [mh-number | mh-type]] [reflect name [timeout value]] [routing] [routing-type routing-number] [sequence value] [time-range name]
    • deny protocol {source-ipv6-prefix / prefix-length | any | host source-ipv6-address | auth} [operator port-number]] {destination-ipv6-prefix/prefix-length | any | host destination-ipv6-address | auth} [operator [port-number]] [dest-option-type [doh-number | doh-type]] [dscp value] [flow-label value] [fragments] [log] [log-input] [mobility] [mobility-type [mh-number | mh-type]] [routing] [routing-type routing-number] [sequence value] [time-range name] [undetermined-transport]


    Example:
    Router(config-ipv6-acl)# permit tcp 2001:DB8:0300:0201::/32 eq telnet any reflect reflectout


    Example:
    
 
		  
    
 

    Example:
     
			 
              
    
 
		  
    
 

    Example:
     
			 
    Router(config-ipv6-acl)# deny tcp host 2001:DB8:1::1 any log-input
    
 
		  
    
 
          		  
			 
     Specifies permit or deny conditions for an IPv6 ACL.
			 
    
 
		   
      
    

    

    

    

    Applying the IPv6 ACL to an Interface
    

    SUMMARY STEPS
      1.   
       
			  
				enable 
			  
		  
      

      2.   
       
			  
				configure 
			  
			  
				terminal 
			  
		  
      

      3.   
       
			  
				interface 
			  
			  
				type 
				number 
			  
		  
      

      4.   
       
			  
				ipv6 
				traffic-filter 
			  
			  
				access-list-name 
			 {in| 
			 out}
		  
      


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 
			  
				enable 
			  
		  
       

      Example:
       
			 
      Router> enable
      
 
		  
      
 
            		  
			 
       Enables privileged EXEC mode. 
			 
      
 
			 
      •  Enter your password if prompted.
				

        • 

      
 
		   
      
      

      Step 2 
			  
				configure 
			  
			  
				terminal 
			  
		  
       

      Example:
       
			 
      Router# configure terminal
      
 
		  
      
 
            		  
			 
       Enters global configuration mode.
			 
      
 
		   
      
      

      Step 3 
			  
				interface 
			  
			  
				type 
				number 
			  
		  
       

      Example:
       
			 
      Router(config)# interface ethernet 0
      
 
		  
      
 
            		  
			 
       Specifies the interface type and number, and enters interface configuration mode.
			 
      
 
		   
      
      

      Step 4 
			  
				ipv6 
				traffic-filter 
			  
			  
				access-list-name 
			 {in| 
			 out}
		  
       

      Example:
       
			 
      Router(config-if)# ipv6 traffic-filter outbound out
      
 
		  
      
 
            		  
			 
       Applies the specified IPv6 access list to the interface specified in the previous step.
			 
      
 
		   
      
      

      

      

      

      

      Controlling Access to a vty
      

      

      Creating an IPv6 ACL to
	 Provide Access Class Filtering
      

      SUMMARY STEPS
        1.   
       
			  
				enable
				
			  
		  
        

        2.   
       
			  
				configure 
			 terminal 
			  
		  
        

        3.   
       
			 ipv6 
				access-list 
			 access-list-name 
			  
		  
        

        4.   
      Do one of the
			 following:
		  
        •  
				 
				  permit 
				  protocol {source-ipv6-prefix/prefix-length | 
				any | 
				host 
				source-ipv6-address} [operator [port-number]] {destination-ipv6-prefix 
				/ 
				prefix-length |
				
				any | 
				host 
				destination-ipv6-address} [operator [port-number]] [dest-option-type [doh-number | 
				doh-type]]
				[dscp 
				value] [flow-label 
				value] [fragments] [log] [log-input] [mobility] [mobility-type [mh-number | 
				mh-type]]
				[routing]
				[routing-type 
				routing-number]
				[sequence 
				value] [time-range 
				name
			 
          • 

        •  
				 
				  deny 
				protocol
				{source-ipv6-prefix/prefix-length | 
				any | 
				host 
				source-ipv6-address} [operator 
				port-number]]
				{destination-ipv6-prefix/prefix-length | 
				any | 
				host 
				destination-ipv6-address} [operator [port-number]] [dest-option-type [doh-number | 
				doh-type]]
				[dscp 
				value]
				[flow-label 
				value]
				[fragments]
				[log] [log-input] [mobility] [mobility-type [mh-number | 
				mh-type]]
				[routing]
				[routing-type 
				routing-number] [sequence 
				value]
				[time-range 
				name] [undetermined-transport
			 
          • 

        

        


      DETAILED STEPS
         Command or ActionPurpose
        Step 1 
			  
				enable
				
			  
		  
         

        Example:
			 
         
				
        Device> enable
        
 
			 
        

		   
              		  
			 
         Enables
				privileged EXEC mode. 
			 
        
 
			 
        • 
				   Enter your
					 password if prompted.
				  

				
          • 

        
 
		   
      
        

        Step 2 
			  
				configure 
			 terminal 
			  
		  
         

        Example:
			 
         
				
        Device# configure terminal
        
 
			 
        

		   
              		  
			 
         Enters global
				configuration mode.
			 
        
 
		   
      
        

        Step 3 
			 ipv6 
				access-list 
			 access-list-name 
			  
		  
         

        Example:
			 
         
				
        Device(config)# ipv6 access-list cisco
        
 
			 
        

		   
              		  
			 
         Defines an IPv6
				ACL, and enters IPv6 access list configuration mode.
			 
        
 
		   
      
        

        Step 4Do one of the
			 following:
		  
        •  
				 
				  permit 
				  protocol {source-ipv6-prefix/prefix-length | 
				any | 
				host 
				source-ipv6-address} [operator [port-number]] {destination-ipv6-prefix 
				/ 
				prefix-length |
				
				any | 
				host 
				destination-ipv6-address} [operator [port-number]] [dest-option-type [doh-number | 
				doh-type]]
				[dscp 
				value] [flow-label 
				value] [fragments] [log] [log-input] [mobility] [mobility-type [mh-number | 
				mh-type]]
				[routing]
				[routing-type 
				routing-number]
				[sequence 
				value] [time-range 
				name
			 
          • 

        •  
				 
				  deny 
				protocol
				{source-ipv6-prefix/prefix-length | 
				any | 
				host 
				source-ipv6-address} [operator 
				port-number]]
				{destination-ipv6-prefix/prefix-length | 
				any | 
				host 
				destination-ipv6-address} [operator [port-number]] [dest-option-type [doh-number | 
				doh-type]]
				[dscp 
				value]
				[flow-label 
				value]
				[fragments]
				[log] [log-input] [mobility] [mobility-type [mh-number | 
				mh-type]]
				[routing]
				[routing-type 
				routing-number] [sequence 
				value]
				[time-range 
				name] [undetermined-transport
			 
          • 

        
 

        Example:
			 
         
				
        Device(config-ipv6-acl)# permit ipv6 host 2001:DB8:0:4::32 any eq telnet
        
 
			 
        

		   

        Example:
			 
         
				
        Device(config-ipv6-acl)# deny ipv6 host 2001:DB8:0:6::6/32 any
        
 
			 
        

		   
              		  
			 
         Specifies
				permit or deny conditions for an IPv6 ACL.
			 
        
 
		   
      
        

        

        

        

        Applying an IPv6 ACL to the
	 Virtual Terminal Line
        

        SUMMARY STEPS
          1.   
       
			 enable 
			  
		  
          

          2.   
       
			  
				configure 
			 terminal 
			  
		  
          

          3.   
       
			  
				line 
			 [aux| 
			 console| 
			 tty| 
			 vty] 
			 line-number[ending-line-number]
		  
          

          4.   
       
			  
				ipv6 
				access-class 
			 ipv6-access-list-name 
			 {in| 
			 out}
		  
          


        DETAILED STEPS
           Command or ActionPurpose
          Step 1 
			 enable 
			  
		  
           

          Example:
			 
           
				
          Device> enable
          
 
			 
          

		   
                		  
			 
           Enables
				privileged EXEC mode. 
			 
          
 
			 
          • 
				   Enter your
					 password if prompted.
				  

				
            • 

          
 
		   
      
          

          Step 2 
			  
				configure 
			 terminal 
			  
		  
           

          Example:
			 
           
				
          Device# configure terminal
          
 
			 
          

		   
                		  
			 
           Enters global
				configuration mode.
			 
          
 
		   
      
          

          Step 3 
			  
				line 
			 [aux| 
			 console| 
			 tty| 
			 vty] 
			 line-number[ending-line-number]
		  
           

          Example:
			 
           
				
          Device(config)# line vty 0 4
          
 
			 
          

		   
                		  
			 
           Identifies a
				specific line for configuration and enters line configuration mode.
			 
          
 
			 
          • 
				   In this
					 example, the 
					 vty keyword is
					 used to specify the virtual terminal lines for remote console access.
				  

				
            • 

          
 
		   
      
          

          Step 4 
			  
				ipv6 
				access-class 
			 ipv6-access-list-name 
			 {in| 
			 out}
		  
           

          Example:
			 
           
				
          Device(config-line)# ipv6 access-class cisco in
          
 
			 
          

		   
                		  
			 
           Filters
				incoming and outgoing connections to and from the device based on an IPv6 ACL.
			 
          
 
		   
      
          

          

          

          

          

          

          Configuration Examples for IPv6 Access Control Lists
          

          Example: Verifying IPv6 ACL
	 Configuration
          

           
		
           In this example,
		  the 
		  show ipv6
				access-list command is used to verify that IPv6 ACLs are
		  configured correctly: 
		
          
 
		
          Device> show ipv6 access-list

IPv6 access list inbound
    permit tcp any any eq bgp reflect tcptraffic (8 matches) sequence 10
    permit tcp any any eq telnet reflect tcptraffic (15 matches) sequence 20
    permit udp any any reflect udptraffic sequence 30

IPv6 access list tcptraffic (reflexive) (per-user)
    permit tcp host 2001:DB8:1::32 eq bgp host 2001:DB8:2::32 eq 11000 timeout 300 (time left 243) sequence 1
    permit tcp host 2001:DB8:1::32 eq telnet host 2001:DB8:2::32 eq 11001 timeout 300 (time left 296) sequence 2

IPv6 access list outbound
    evaluate udptraffic
    evaluate tcptraffic
          
 
	 
          

          

          

          Example: Creating and
	 Applying an IPv6 ACL
          

           
		 
		 
		 
		 
		
           The following
		  example shows how to restrict HTTP access to certain hours during the day and
		  log any activity outside of the permitted hours: 
		
          
 
		
          Device# configure terminal
Device(config)# time-range lunchtime
Device(config-time-range)# periodic weekdays 12:00 to 13:00
Device(config-time-range)# exit
Device(config)# ipv6 access-list OUTBOUND
Device(config-ipv6-acl)# permit tcp any any eq www time-range lunchtime
Device(config-ipv6-acl)# deny tcp any any eq www log-input
Device(config-ipv6-acl)# permit tcp 2001:DB8::/32 any
Device(config-ipv6-acl)# permit udp 2001:DB8::/32 any
Device(config-ipv6-acl)# end
          
 
	 
          

          

          

          Example: Controlling Access
	 to a vty
          

           
		
           In the following
		  example, incoming connections to the virtual terminal lines 0 to 4 are filtered
		  based on the IPv6 access list named acl1:
		
          
 
		
          ipv6 access-list acl1
 permit ipv6 host 2001:DB8:0:4::2/32 any
!
line vty 0 4
 ipv6 access-class acl1 in
          
 
	 
          

          

          

          

          Additional References
          

          Related Documents
           
		 
		

          Related Topic 
				  
          
          		

          Document Title 
				  
          
          		

          
          

           
					 
           IPv6 addressing and connectivity 
					 
          
 
				            		
 
					 
           IPv6 Configuration Guide
          
 
				            		

          

           
					 
          Cisco IOS commands 
					 
          
 
				            		
 
					 
          Cisco IOS Master Commands List, All Releases
          
 
				            		

          

           
					 
          IPv6 commands 
					 
          
 
				            		
 
					 
          Cisco IOS IPv6 Command Reference
          
 
				            		

          

           
					 
          Cisco IOS IPv6 features 
					 
          
 
				            		

           
					 Cisco IOS IPv6 Feature Mapping
          
          		

          
          

          

          
 
	 
          

          Standards and RFCs
           
		 
		

          Standard/RFC 
				  
          
          		

          Title 
				  
          
          		

          
          

           
					 
          RFCs for IPv6 
					 
          
 
				            		

					 
          IPv6 RFCs
          

				            		

          
          

          

          
 
	 
          

          MIBs
           
		 
		

           
					 
           MIB 
					 
          
 
				            		
 
					 
           MIBs Link 
					 
          
 
				            		

          
          

           
					 
           
					 
          
 
					 
          CISCO-UNIFIED-FIREWALL-MIB 
					 
          
 
				            		
 
					 
           To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:
          
 
					 
           
						http:/​/​www.cisco.com/​go/​mibs
          
 
				            		

          
          

          

          
 
	 
          

          Technical Assistance
           
		 
		

          Description 
				  
          
          		

          Link 
				  
          
          		

          
          

           
					 
          The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password. 
					 
          
 
				            		
 
					 
           
						http:/​/​www.cisco.com/​cisco/​web/​support/​index.html
          
 
				            		

          
          

          

          
 
	 
          

          

          

          Feature Information for IPv6 Access Control Lists
          

           
		
          The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature. 
		
          
 
		
          Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to 
		  www.cisco.com/​go/​cfn. An account on Cisco.com is not required. 
		
          
 
	 
          


          Table 1 Feature Information for IPv6 Access Control Lists
          Feature Name 
			 
          
          		

          Releases 
			 
          
          		

          Feature Information 
			 
          
          		

          
          

           
				
          IPv6 Services: Standard Access Control Lists 
				
          
 
			           		
 
				
          12.0(22)S 
				
          

				
          12.2(14)S 
				
          

				
          12.2(28)SB 
				
          

				
          12.2(25)SG 
				
          

				
          12.2(33)SRA
				
          

				
          12.2(17a)SX1
				
          

				
          12.2(2)T
				
          

				
          12.3
				
          

				
          12.3(2)T
				
          

				
          12.4
				
          

				
          12.4(2)T
				
          

				
          15.0(1)S
				
          
 
			           		
 
				
          Access lists determine what traffic is blocked and what traffic is forwarded at router interfaces and allow filtering based on source and destination addresses, inbound and outbound to a specific interface.
				
          
 
			           		

          

          
				
          IPv6 Services: Extended Access Control Lists 
				
          

			           		

				
          12.0(23)S 
				
          

				
          12.2(14)S 
				
          

				
          12.2(28)SB 
				
          

				
          12.2(25)SG 
				
          

				
          12.2(33)SRA
				
          

				
          12.2(17a)SX1
				
          

				
          12.2(13)T 
				
          

				
          12.3
				
          

				
          12.3(2)T
				
          

				
          12.4
				
          

				
          12.4(2)T
				
          

				
          15.0(1)S
				
          
 
			           		

				
          Standard IPv6 ACL functionality was extended to support traffic filtering based on IPv6 option headers and optional, upper-layer protocol type information for finer granularity of control.