Cisco PIX 500 Series Configuration Manual page 357

Chapter 18 Permitting or Denying Network Access
Applying an Access List to an Interface
The per-user-override keyword allows dynamic access lists that are downloaded for user authorization
to override the access list assigned to the interface. For example, if the interface access list denies all
traffic from 10.0.0.0, but the dynamic access list permits all traffic from 10.0.0.0, then the dynamic
access list overrides the interface access list for that user. See the "Configuring RADIUS Authorization"
section for more information about per-user access lists. The per-user-override keyword is only
available for inbound access lists.
For connectionless protocols, you need to apply the access list to the source and destination interfaces
if you want traffic to pass in both directions. For example, you can allow BGP in an EtherType access
list in transparent mode, and you need to apply the access list to both interfaces.
The following example illustrates the commands required to enable access to an inside web server with
the IP address 209.165.201.12 (this IP address is the address visible on the outside interface after NAT):
hostname(config)# access-list ACL_OUT extended permit tcp any host 209.165.201.12 eq www
hostname(config)# access-group ACL_OUT in interface outside
You also need to configure NAT for the web server.
The following access lists allow all hosts to communicate between the inside and hr networks, but only
specific hosts to access the outside network:
hostname(config)# access-list ANY extended permit ip any any
hostname(config)# access-list OUT extended permit ip host 209.168.200.3 any
hostname(config)# access-list OUT extended permit ip host 209.168.200.4 any
hostname(config)# access-group ANY in interface inside
hostname(config)# access-group ANY in interface hr
hostname(config)# access-group OUT out interface outside
For example, the following sample access list allows common EtherTypes originating on the inside
interface:
hostname(config)# access-list ETHER ethertype permit ipx
hostname(config)# access-list ETHER ethertype permit bpdu
hostname(config)# access-list ETHER ethertype permit mpls-unicast
hostname(config)# access-group ETHER in interface inside
The following access list allows some EtherTypes through the security appliance, but denies all others:
hostname(config)# access-list ETHER ethertype permit 0x1234
hostname(config)# access-list ETHER ethertype permit bpdu
hostname(config)# access-list ETHER ethertype permit mpls-unicast
hostname(config)# access-group ETHER in interface inside
hostname(config)# access-group ETHER in interface outside
The following access list denies traffic with EtherType 0x1256 but allows all others on both interfaces:
hostname(config)# access-list nonIP ethertype deny 1256
hostname(config)# access-list nonIP ethertype permit any
hostname(config)# access-group ETHER in interface inside
hostname(config)# access-group ETHER in interface outside
The following example uses object groups to permit specific traffic on the inside interface:
!
hostname (config)# object-group service myaclog
hostname (config-service)# service-object tcp source range 2000 3000
hostname (config-service)# service-object tcp source range 3000 3010 destinatio$
hostname (config-service)# service-object ipsec
hostname (config-service)# service-object udp destination range 1002 1006
hostname (config-service)# service-object icmp echo
Cisco Security Appliance Command Line Configuration Guide
18-3
OL-12172-03