华为交换机防止仿冒网关ARP攻击配置实例

1、华为交换机防止仿冒网关ARP攻击配置实例作者：未知 文章来源：转贴 点击数：1059 更新时间：2007-7-3 16:27:00 二层交换机实现仿冒网关的ARP防攻击： 一、组网需求：1. 二层交换机阻止网络用户仿冒网关IP的ARP攻击二、组网图：图1二层交换机防ARP攻击组网S3552P是三层设备，其中IP：100.1.1.1是所有PC的网关，S3552P上的网关MAC地址为000f-e200-3999。PC-B上装有ARP攻击软件。现在需要对S3026C_A进行一些特殊配置，目的是过滤掉仿冒网关IP的ARP报文。三、配置步骤对于二层交换机如S3026C等支持用户自定义ACL(number

2、为5000到5999)的交换机，可以配置ACL来进行ARP报文过滤。全局配置ACL禁止所有源IP是网关的ARP报文acl num 5000rule 0 deny 0806 ffff 24 64010101 ffffffff 40rule 1 permit 0806 ffff 24 000fe2003999 ffffffffffff 34其中rule0把整个S3026C_A的端口冒充网关的ARP报文禁掉，其中斜体部分64010101是网关IP地址100.1.1.1的16进制表示形式。Rule1允许通过网关发送的ARP报文，斜体部分为网关的mac地址000f-e200-3999。注意：配置Rule

3、时的配置顺序，上述配置为先下发后生效的情况。在S3026C-A系统视图下发acl规则：S3026C-A packet-filter user-group 5000这样只有S3026C_A上连网关设备才能够发送网关的ARP报文，其它主机都不能发送假冒网关的arp响应报文。三层交换机实现仿冒网关的ARP防攻击一、组网需求：1. 三层交换机实现防止同网段的用户仿冒网关IP的ARP攻击二、组网图图2 三层交换机防ARP攻击组网三、配置步骤1. 对于三层设备，需要配置过滤源IP是网关的ARP报文的ACL规则，配置如下ACL规则：acl number 5000rule 0 deny 0806 ffff 2

4、4 64010105 ffffffff 40rule0禁止S3526E的所有端口接收冒充网关的ARP报文，其中斜体部分64010105是网关IP地址100.1.1.5的16进制表示形式。2. 下发ACL到全局S3526E packet-filter user-group 5000仿冒他人IP的ARP防攻击一、组网需求：作为网关的设备有可能会出现错误ARP的表项，因此在网关设备上还需对用户仿冒他人IP的ARP攻击报文进行过滤。二、组网图：参见图1和图2三、配置步骤：1. 如图1所示，当PC-B发送源IP地址为PC-D的arp reply攻击报文，源mac是PC-B的mac (000d-88f8-

5、09fa)，源ip是PC-D的ip(100.1.1.3)，目的ip和mac是网关(3552P)的，这样3552上就会学习到错误的arp，如下所示：-错误arp表项- IPAddressMACAddressVLANIDPortNameAgingType 100.1.1.4000d-88f8-09fa1Ethernet0/220Dynamic 100.1.1.3000f-3d81-45b41Ethernet0/220Dynamic从网络连接可以知道PC-D的arp表项应该学习到端口E0/8上，而不应该学习到E0/2端口上。但实际上交换机上学习到该ARP表项在E0/2。上述现象可以在S3552上配置

6、静态ARP实现防攻击：arpstatic100.1.1.3000f-3d81-45b41e0/82. 在图2 S3526C上也可以配置静态ARP来防止设备学习到错误的ARP表项。3. 对于二层设备(S3050C和S3026E系列)，除了可以配置静态ARP外，还可以配置IP+MAC+port绑定，比如在S3026C端口E0/4上做如下操作：am user-bind ip-addr 100.1.1.4 mac-addr 000d-88f8-09fa int e0/4则IP为100.1.1.4并且MAC为000d-88f8-09fa的ARP报文可以通过E0/4端口，仿冒其它设备的ARP报文则无法通过

7、，从而不会出现错误ARP表项。四、配置关键点：此处仅仅列举了部分Quidway S系列以太网交换机的应用。在实际的网络应用中，请根据配置手册确认该产品是否支持用户自定义ACL和地址绑定。仅仅具有上述功能的交换机才能防止ARP欺骗。实际配置时注意偏移量的值，如不清楚请咨询华为售后工程师。6503交换机配置实例：acl number 5000rule 0 deny 0806 ffff 24 0a4e0401 ffffffff 40rule 1 permit 0806 ffff 24 000fe218ded7 ffffffffffff 34interface GigabitEthernet1/0/9

8、description Connect-to-Vlan4_S3928TP_1_G1/1/1duplex fullspeed 1000port link-type trunkport trunk permit vlan allqospacket-filter inbound user-group 5000 rule 0 system-index 1packet-filter inbound user-group 5000 rule 1 system-index 23900系列交换机配置实例：acl number 5000rule 0 deny 0806 ffff 16 0a4e0401 ffff

9、ffff 32 rule 1 permit 0806 ffff 16 000fe218ded7 ffffffffffff 32rule2 deny 0806 ffff 16 00142a6cf8f4 ffffffffffff 32rule 3 deny 0806 ffff 16 0a4e04ba ffffffffffff 3286中交换机配置：display current-configuration #local-server nas-ip 127.0.0.1 key huawei#domain default enable system#queue-scheduler wrr 1 2 3

10、4 5 9 13 15#radius scheme system#domain system#local-user pandapassword simple pingafanservice-type telnetlevel 3#acl number 5000rule 0 deny 0806 ffff 24 0a4e0401 ffffffff 40rule 1 permit 0806 ffff 24 000fe218ded7 ffffffffffff 34#vlan 1#vlan 10#vlan 40#interface Vlan-interface1ip address 10.78.1.42

11、255.255.255.0#interface Vlan-interface40#interface Aux1/0/0#interface Ethernet1/0/1port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/2port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound u

12、ser-group 5000 rule 1#interface Ethernet1/0/3port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/4port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethern

13、et1/0/5port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/6port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/7port access vlan 40packet-filte

14、r inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/8port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/9port access vlan 40packet-filter inbound user-group 5000 rule 0packet

15、-filter inbound user-group 5000 rule 1#interface Ethernet1/0/10port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/11port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule

16、 1#interface Ethernet1/0/12port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/13port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/14port acce

17、ss vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/15port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/16port access vlan 40packet-filter inbound user

18、-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/17port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/18port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbo

19、und user-group 5000 rule 1#interface Ethernet1/0/19port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/20port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface

20、 Ethernet1/0/21port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/22port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/23port access vlan 40packet-filter inbound user-group 5000 rule 0packet-filter inbound user-group 5000 rule 1#interface Ethernet1/0/24port access vlan 40packet-filter inbound user-group 5000 ru