静态IOS路由器和动态PIX之间的动态IPSec配置示例

在静态寻址IOS路由器和动态地寻址PIX之间的动态IPSec与NAT的配置示例
Cisco ASA 5500 系列版本 7.x 运行类似 PIX 版本 7.x 的软件版本。本文档中的配置适用于这两个产品系列。
在 PIX 上，access-list 和 nat 0 命令协同工作。当 10.1.1.0 网络上的用户访问 10.2.1.0 网络时，将使用访问列表允许 10.1.1.0 网络数据流在没有 NAT 的情况下进行加密。在路由器上，将使用 access-list 命令允许 10.2.1.0 网络数据流在没有 NAT 的情况下进行加密。然而，当同样用户去别处(类似互联网)时，他们翻译对外部接口IP地址通过端口地址转换(PAT)。
要使通过隧道的数据流不经过 PAT，而使到达 Internet 的数据流经过 PAT，则必须在 PIX 安全设备上使用以下配置命令。
access-list nonat permit ip 10.1.1.0 255.255.255.0 10.2.2.0 255.255.255.0
nat (inside) 0 access-list nonat
nat (inside) 1 10.1.1.0 255.255.255.0 0 0

pix 7.0以上版本

pixfirewall#show running-config
 PIX Version 7.2(2)
!
hostname pixfirewall
enable password 8Ry2YjIyt7RRXU24 encrypted
names
!

!--- The interface dynamically learns its IP address
!--- from the service provider.

interface Ethernet0
 nameif outside
 security-level 0
 ip address dhcp
!
interface Ethernet1
 nameif inside
 security-level 100
 ip address 10.1.1.2 255.255.255.0
!
!


!-- Output is suppressed.

!
passwd 2KFQnbNIdI.2KYOU encrypted
ftp mode passive



!--- This is the access list (IPsec-traffic) used for the VPN interesting traffic
!--- to be encrypted.



access-list IPSec-traffic extended permit ip 10.1.1.0 255.255.255.0 10.2.1.0 255.255.255.0


!--- This access list (nonat) is used for a nat zero command that prevents
!--- traffic which matches the access list from undergoing NAT.


access-list NO-NAT extended permit ip 10.1.1.0 255.255.255.0 10.2.1.0 255.255.255.0


pager lines 24
mtu inside 1500
mtu outside 1500
no failover
icmp unreachable rate-limit 1 burst-size 1
no asdm history enable
arp timeout 14400



!--- NAT 0 prevents NAT for networks specified in the ACL - nonat.
!--- The nat 1 command specifies PAT using the
!--- outside interface for all other traffic.


global (outside) 1 interface
nat (inside) 0 access-list NO-NAT
nat (inside) 1 0.0.0.0 0.0.0.0

route outside 0.0.0.0 0.0.0.0 172.16.1.2 1

timeout xlate 3:00:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02
timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00
timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00
timeout uauth 0:05:00 absolute
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart


!--- PHASE 2 CONFIGURATION ---!
!--- The encryption types for Phase 2 are defined here.
!--- A triple single DES encryption with
!--- the md5 hash algorithm is used.


crypto ipsec transform-set DYN-TS esp-des esp-md5-hmac


!--- Define which traffic should be sent to the IPsec peer.



crypto map IPSEC 10 match address IPSec-traffic


!--- Sets the IPsec peer.


crypto map IPSEC 10 set peer 192.168.1.2


!--- Sets the IPsec transform set "DYN-TS"
!--- to be used with the crypto map entry "IPSEC".


crypto map IPSEC 10 set transform-set DYN-TS


!--- Specifies the interface to be used with
!--- the settings defined in this configuration.


crypto map IPSEC interface outside


!--- Enables IPsec on the outside interface.

crypto isakmp enable outside


!--- PHASE 1 CONFIGURATION ---!

!--- This configuration uses isakmp policy 10.
!--- Policy 65535 is included in the configuration by default.
!--- The configuration commands here define the Phase
!--- 1 policy parameters that are used.

crypto isakmp policy 10
 authentication pre-share
 encryption des
 hash md5
 group 1
 lifetime 86400


crypto isakmp policy 65535
 authentication pre-share
 encryption 3des
 hash sha
 group 2
 lifetime 86400

!--- In order to create and manage the database of connection-specific records
!--- for IPsec-L2L—IPsec tunnels, use the tunnel-group
!--- command in global configuration mode.
!--- For L2L connections the name of the tunnel group MUST be the IP
!--- address of the IPsec peer.


tunnel-group 192.168.1.2 type ipsec-l2l


!--- Enter the pre-shared-key in IPsec-attribute parameters
!--- in order to configure the authentication method.


tunnel-group 192.168.1.2 ipsec-attributes
 pre-shared-key *

telnet timeout 5
ssh timeout 5
console timeout 0
!
class-map inspection_default
 match default-inspection-traffic
!
!
policy-map type inspect dns preset_dns_map
 parameters
  message-length maximum 512
policy-map global_policy
 class inspection_default
  inspect dns preset_dns_map
  inspect ftp
  inspect h323 h225
  inspect h323 ras
  inspect netbios
  inspect rsh
  inspect rtsp
  inspect skinny
  inspect esmtp
  inspect sqlnet
  inspect sunrpc
  inspect tftp
  inspect sip
  inspect xdmcp
!
service-policy global_policy global
prompt hostname context
Cryptochecksum:d609c9eaf51c154f147b3b4ba3c834e0
: end
pixfirewall#

route配置

Router#show running-config
Current configuration : 1354 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname Router
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
!
resource policy
!
!
!
ip cef
!


!--- Configuration for IKE policies.
!--- Enables the IKE policy configuration (config-isakmp)
!--- command mode, where you can specify the parameters that
!--- are used during an IKE negotiation.


crypto isakmp policy 10
 hash md5
 authentication pre-share


!--- Specifies the preshared key "cisco123" which should
!--- be identical at both peers. This is a global
!--- configuration mode command. It accepts any peer which matches
!--- the pre-shared key.

crypto isakmp key cisco123 address 0.0.0.0 0.0.0.0
!

!--- Configuration for IPsec policies.
!--- Enables the crypto transform configuration mode,
!--- where you can specify the transform sets that are used
!--- during an IPsec negotiation.


crypto ipsec transform-set DYN-TS esp-des esp-md5-hmac


!--- IPsec policy, Phase 2.


crypto dynamic-map DYN 10



!--- Configures IPsec to use the transform-set
!--- "DYN-TS" defined earlier in this configuration.


 set transform-set DYN-TS



crypto map IPSEC 10 ipsec-isakmp dynamic DYN
!
interface Ethernet0/0
 ip address 192.168.1.2 255.255.255.0
 ip nat outside
 ip virtual-reassembly
 half-duplex

!--- Configures the interface to use the
!--- crypto map "IPSEC" for IPsec.

 crypto map IPSEC
!
interface FastEthernet1/0
 ip address 10.2.1.1 255.255.255.0
 ip nat inside
 ip virtual-reassembly
 duplex auto
 speed auto
!
interface Serial2/0
 no ip address
 shutdown
 no fair-queue
!
interface Serial2/1
 no ip address
 shutdown
!
interface Serial2/2
 no ip address
 shutdown
!
interface Serial2/3
 no ip address
 shutdown
!
ip http server
no ip http secure-server
!
ip route 0.0.0.0 0.0.0.0 192.168.1.1
!
ip nat inside source list 100 interface Ethernet0/0 overload
!

!--- This ACL 100 identifies the traffic flows and be PATed
!--- via the outside interface( Ethernet0/0).


access-list 100 deny ip 10.2.1.0 0.0.0.255 10.1.1.0 0.0.0.255
access-list 100 permit ip 10.2.1.0 0.0.0.255 any



control-plane
!

!
line con 0
line aux 0
line vty 0 4
!
!
end

清除安全关联 (SA)

在 PIX 的特权模式下使用以下这些命令：

clear [crypto] ipsec sa - 删除活动 IPsec SA。关键字 crypto 是可选的。

clear [crypto] isakmp sa - 删除活动 IKE SA。关键字 crypto 是可选的。
show crypto isakmp sa
show crypto ipsec sa
PIX 安全设备 - debug 输出

debug crypto ipsec 7 - 显示第 2 阶段的 IPsec 协商。

debug crypto isakmp 7 - 显示第 1 阶段的 ISAKMP 协商。

远程 IOS 路由器 - debug 输出

debug crypto ipsec - 显示第 2 阶段的 IPsec 协商。

debug crypto isakmp - 显示第 1 阶段的 ISAKMP 协商。