对我来说似乎很清楚,链接本地地址和唯一本地地址至少应被过滤。


除了LLA / ULA之外还有其他应过滤的内容吗?
对于LLA,标准做法是对完整的fe80 :: / 10进行覆盖过滤,还是仅过滤fe80 :: / 64?


#1 楼

RFC 6890第2.2.3节描述了IPv6的专用前缀。链接在这里:

http://tools.ietf.org/html/rfc6890#page-14

要包括的前缀为:

               +----------------------+------------------+
               | Attribute            | Value            |
               +----------------------+------------------+
               | Address Block        | ::1/128          |
               | Name                 | Loopback Address |
               | RFC                  | [RFC4291]        |
               | Allocation Date      | February 2006    |
               | Termination Date     | N/A              |
               | Source               | False            |
               | Destination          | False            |
               | Forwardable          | False            |
               | Global               | False            |
               | Reserved-by-Protocol | True             |
               +----------------------+------------------+

                    Table 17: Loopback Address

             +----------------------+---------------------+
             | Attribute            | Value               |
             +----------------------+---------------------+
             | Address Block        | ::/128              |
             | Name                 | Unspecified Address |
             | RFC                  | [RFC4291]           |
             | Allocation Date      | February 2006       |
             | Termination Date     | N/A                 |
             | Source               | True                |
             | Destination          | False               |
             | Forwardable          | False               |
             | Global               | False               |
             | Reserved-by-Protocol | True                |
             +----------------------+---------------------+

                   Table 18: Unspecified Address

            +----------------------+---------------------+
            | Attribute            | Value               |
            +----------------------+---------------------+
            | Address Block        | 64:ff9b::/96        |
            | Name                 | IPv4-IPv6 Translat. |
            | RFC                  | [RFC6052]           |
            | Allocation Date      | October 2010        |
            | Termination Date     | N/A                 |
            | Source               | True                |
            | Destination          | True                |
            | Forwardable          | True                |
            | Global               | True                |
            | Reserved-by-Protocol | False               |
            +----------------------+---------------------+

              Table 19: IPv4-IPv6 Translation Address

             +----------------------+---------------------+
             | Attribute            | Value               |
             +----------------------+---------------------+
             | Address Block        | ::ffff:0:0/96       |
             | Name                 | IPv4-mapped Address |
             | RFC                  | [RFC4291]           |
             | Allocation Date      | February 2006       |
             | Termination Date     | N/A                 |
             | Source               | False               |
             | Destination          | False               |
             | Forwardable          | False               |
             | Global               | False               |
             | Reserved-by-Protocol | True                |
             +----------------------+---------------------+

                   Table 20: IPv4-Mapped Address

          +----------------------+----------------------------+
          | Attribute            | Value                      |
          +----------------------+----------------------------+
          | Address Block        | 100::/64                   |
          | Name                 | Discard-Only Address Block |
          | RFC                  | [RFC6666]                  |
          | Allocation Date      | June 2012                  |
          | Termination Date     | N/A                        |
          | Source               | True                       |
          | Destination          | True                       |
          | Forwardable          | True                       |
          | Global               | False                      |
          | Reserved-by-Protocol | False                      |
          +----------------------+----------------------------+

                   Table 21: Discard-Only Prefix

          +----------------------+---------------------------+
          | Attribute            | Value                     |
          +----------------------+---------------------------+
          | Address Block        | 2001::/23                 |
          | Name                 | IETF Protocol Assignments |
          | RFC                  | [RFC2928]                 |
          | Allocation Date      | September 2000            |
          | Termination Date     | N/A                       |
          | Source               | False[1]                  |
          | Destination          | False[1]                  |
          | Forwardable          | False[1]                  |
          | Global               | False[1]                  |
          | Reserved-by-Protocol | False                     |
          +----------------------+---------------------------+

         [1] Unless allowed by a more specific allocation.

                +----------------------+----------------+
                | Attribute            | Value          |
                +----------------------+----------------+
                | Address Block        | 2001::/32      |
                | Name                 | TEREDO         |
                | RFC                  | [RFC4380]      |
                | Allocation Date      | January 2006   |
                | Termination Date     | N/A            |
                | Source               | True           |
                | Destination          | True           |
                | Forwardable          | True           |
                | Global               | False          |
                | Reserved-by-Protocol | False          |
                +----------------------+----------------+

                         Table 23: TEREDO

                +----------------------+----------------+
                | Attribute            | Value          |
                +----------------------+----------------+
                | Address Block        | 2001:2::/48    |
                | Name                 | Benchmarking   |
                | RFC                  | [RFC5180]      |
                | Allocation Date      | April 2008     |
                | Termination Date     | N/A            |
                | Source               | True           |
                | Destination          | True           |
                | Forwardable          | True           |
                | Global               | False          |
                | Reserved-by-Protocol | False          |
                +----------------------+----------------+

                      Table 24: Benchmarking

                +----------------------+---------------+
                | Attribute            | Value         |
                +----------------------+---------------+
                | Address Block        | 2001:db8::/32 |
                | Name                 | Documentation |
                | RFC                  | [RFC3849]     |
                | Allocation Date      | July 2004     |
                | Termination Date     | N/A           |
                | Source               | False         |
                | Destination          | False         |
                | Forwardable          | False         |
                | Global               | False         |
                | Reserved-by-Protocol | False         |
                +----------------------+---------------+

                      Table 25: Documentation

                 +----------------------+--------------+
                 | Attribute            | Value        |
                 +----------------------+--------------+
                 | Address Block        | 2001:10::/28 |
                 | Name                 | ORCHID       |
                 | RFC                  | [RFC4843]    |
                 | Allocation Date      | March 2007   |
                 | Termination Date     | March 2014   |
                 | Source               | False        |
                 | Destination          | False        |
                 | Forwardable          | False        |
                 | Global               | False        |
                 | Reserved-by-Protocol | False        |
                 +----------------------+--------------+

                         Table 26: ORCHID

                +----------------------+---------------+
                | Attribute            | Value         |
                +----------------------+---------------+
                | Address Block        | 2002::/16 [2] |
                | Name                 | 6to4          |
                | RFC                  | [RFC3056]     |
                | Allocation Date      | February 2001 |
                | Termination Date     | N/A           |
                | Source               | True          |
                | Destination          | True          |
                | Forwardable          | True          |
                | Global               | N/A [2]       |
                | Reserved-by-Protocol | False         |
                +----------------------+---------------+

                  [2] See [RFC3056] for details.

                          Table 27: 6to4

                 +----------------------+--------------+
                 | Attribute            | Value        |
                 +----------------------+--------------+
                 | Address Block        | fc00::/7     |
                 | Name                 | Unique-Local |
                 | RFC                  | [RFC4193]    |
                 | Allocation Date      | October 2005 |
                 | Termination Date     | N/A          |
                 | Source               | True         |
                 | Destination          | True         |
                 | Forwardable          | True         |
                 | Global               | False        |
                 | Reserved-by-Protocol | False        |
                 +----------------------+--------------+

                      Table 28: Unique-Local

            +----------------------+-----------------------+
            | Attribute            | Value                 |
            +----------------------+-----------------------+
            | Address Block        | fe80::/10             |
            | Name                 | Linked-Scoped Unicast |
            | RFC                  | [RFC4291]             |
            | Allocation Date      | February 2006         |
            | Termination Date     | N/A                   |
            | Source               | True                  |
            | Destination          | True                  |
            | Forwardable          | False                 |
            | Global               | False                 |
            | Reserved-by-Protocol | True                  |
            +----------------------+-----------------------+

                      Table 29: Linked-Scoped Unicast


这应该足够了。还可以选择过滤Bogon,但是除非您设置与Team Cymru或类似的对等网络,否则感觉有些过大。

评论


我不同意所有特殊目的地址“不应路由”或“至少应过滤”。例如,有些标记为“ Forwardable”和“ Global”,尤其是NAT64标记为64:ff9b :: / 96。

– Zevlag
13年5月16日在3:21



显然,如果您使用这些前缀中的任何一个,则不应过滤它们。也许您正在使用Teredo等,但是除非您正在运行NAT或隧道,否则默认姿势应该是对它们进行过滤。

–丹尼尔·迪布(Daniel Dib)
13年5月16日下午4:07

为什么要过滤2002 :: / 16?这将阻止使用6to4作为过渡机制的任何人与您进行通信。

– Paul Gear
13年7月20日在21:12

#2 楼

您可以使用三个选项。

第一个也是最准确的一个,就是与Team Cymru建立对等关系,正如SimonJGreen解释的那样。您拥有最准确的列表的优点,而缺点是维护对等关系,策略声明/路由映射等。

第二种方法是拒绝前缀“您应该(例如,本地链接前缀,旧的6Bone 3FFE :: / 16前缀等),然后将其与您应该看到的前缀结合起来。参见以下示例。优点是这是最简单的配置,缺点是它不如第一个选项准确。

第三条方法(您永远不应实现)是采用当前的ipv6 bogon列表(由Team Cymru发布),并将其作为静态过滤器粘贴到您的配置中。这是几年前很多人对ipv4所做的事情,今天导致了很多苦难...请勿使用此选项。

作为示例,下面是一个不错的ipv6前缀列​​表和允许拒绝的前缀列表:

ipv6 prefix-list in-filter-v6 seq 5 deny 3ffe::/16 le 128 
ipv6 prefix-list in-filter-v6 seq 10 deny 2001:db8::/32 le 128 
ipv6 prefix-list in-filter-v6 seq 15 permit 2001::/32 
ipv6 prefix-list in-filter-v6 seq 20 deny 2001::/32 le 128 
ipv6 prefix-list in-filter-v6 seq 25 permit 2002::/16 
ipv6 prefix-list in-filter-v6 seq 30 deny 2002::/16 le 128 
ipv6 prefix-list in-filter-v6 seq 35 deny ::/8 le 128 
ipv6 prefix-list in-filter-v6 seq 40 deny fe00::/9 le 128 
ipv6 prefix-list in-filter-v6 seq 45 deny ff00::/8 le 128 
ipv6 prefix-list in-filter-v6 seq 50 permit 2000::/3 le 48 
ipv6 prefix-list in-filter-v6 seq 55 deny ::/0 le 128 


#3 楼

请参阅http://www.team-cymru.org/Services/Bogons/http.html

上的IPv6 Fullbogons列表。执行自动过滤。

下面是在Cisco上自动过滤的示例:

router bgp <your asn>
 ! Session 1
 neighbor A.B.C.D remote-as 65332
 neighbor A.B.C.D description <your description>
 neighbor A.B.C.D ebgp-multihop 255
 neighbor A.B.C.D password <your password>
 ! Session 2
 neighbor E.F.G.H remote-as 65332
 neighbor E.F.G.H description <your description>
 neighbor E.F.G.H ebgp-multihop 255
 neighbor E.F.G.H password <your password>
!
 address-family ipv4
  ! Session 1
  neighbor A.B.C.D activate
  neighbor A.B.C.D soft-reconfiguration inbound
  neighbor A.B.C.D prefix-list cymru-out-v4 out
  neighbor A.B.C.D route-map CYMRUBOGONS-V4 in
  ! Session 2
  neighbor E.F.G.H activate
  neighbor E.F.G.H soft-reconfiguration inbound
  neighbor E.F.G.H prefix-list cymru-out-v4 out
  neighbor E.F.G.H route-map CYMRUBOGONS-V4 in
!
 address-family ipv6
  ! Session 1
  neighbor A.B.C.D activate
  neighbor A.B.C.D soft-reconfiguration inbound
  neighbor A.B.C.D prefix-list cymru-out-v6 out
  neighbor A.B.C.D route-map CYMRUBOGONS-V6 in
  ! Session 2
  neighbor E.F.G.H activate
  neighbor E.F.G.H soft-reconfiguration inbound
  neighbor E.F.G.H prefix-list cymru-out-v6 out
  neighbor E.F.G.H route-map CYMRUBOGONS-V6 in
!
! Depending on IOS version, you may need to configure your router
! for new-style community syntax.
ip bgp-community new-format
!
ip community-list 100 permit 65332:888
!
ip route 192.0.2.1 255.255.255.255 Null0
!
ip prefix-list cymru-out-v4 seq 5 deny 0.0.0.0/0 le 32
!
ipv6 route 2001:DB8:0:DEAD:BEEF::1/128 Null0
!
ipv6 prefix-list cymru-out-v6 seq 5 deny ::/0 le 128
!
route-map CYMRUBOGONS-V6 permit 10
description IPv6 Filter bogons learned from cymru.com bogon route-servers
match community 100
set ipv6 next-hop 2001:DB8:0:DEAD:BEEF::1
!
route-map CYMRUBOGONS-V4 permit 10
description IPv4 Filter bogons learned from cymru.com bogon route-servers
match community 100
set ip next-hop 192.0.2.1


这是一个适用于JunOS的示例:

/*
* Define BGP peer group
*/
delete protocols bgp group cymru-bogons
set protocols bgp group cymru-bogons type external
set protocols bgp group cymru-bogons description "cymru fullbogon bgp feed (ipv4 + 6)"
set protocols bgp group cymru-bogons multihop ttl 255
set protocols bgp group cymru-bogons import cymru-bogons-in
/*
* Define MD5 password in quotes
*/
set protocols bgp group cymru-bogons authentication-key "<YOUR PASSWORD>"
set protocols bgp group cymru-bogons export deny-all
set protocols bgp group cymru-bogons peer-as 65332
/*
* Replace values below as appropriate
*/
set protocols bgp group cymru-bogons neighbor A.B.C.D local-address <YOUR IP>
set protocols bgp group cymru-bogons neighbor A.B.C.D family inet unicast
set protocols bgp group cymru-bogons neighbor A.B.C.D family inet6 unicast
set protocols bgp group cymru-bogons neighbor E.F.G.H local-address <YOUR IP>
set protocols bgp group cymru-bogons neighbor E.F.G.H family inet unicast
set protocols bgp group cymru-bogons neighbor E.F.G.H family inet6 unicast
/*
* Define CYMRU import policy
*/
delete policy-options policy-statement cymru-bogons-in
set policy-options policy-statement cymru-bogons-in term 1 from family inet
set policy-options policy-statement cymru-bogons-in term 1 from community comm-cymru-bogon
set policy-options policy-statement cymru-bogons-in term 1 then community add no-export
set policy-options policy-statement cymru-bogons-in term 1 then next-hop discard
set policy-options policy-statement cymru-bogons-in term 1 then accept
set policy-options policy-statement cymru-bogons-in term 2 from family inet6
set policy-options policy-statement cymru-bogons-in term 2 from community comm-cymru-bogon
set policy-options policy-statement cymru-bogons-in term 2 then community add no-export
set policy-options policy-statement cymru-bogons-in term 2 then next-hop discard
set policy-options policy-statement cymru-bogons-in term 2 then accept
set policy-options policy-statement cymru-bogons-in then reject
/*
* Define deny-all export policy
*/
delete policy-options policy-statement deny-all
set policy-options policy-statement deny-all then reject
/*
* Define CYMRU Bogon community
*/
delete policy-options community comm-cymru-bogon
set policy-options community comm-cymru-bogon members no-export
set policy-options community comm-cymru-bogon members 65332:888
/*
* Define internal no-export community
*/
delete policy-options community comm-no-export
set policy-options community comm-no-export members no-export


#4 楼

该IPv6过滤建议有些陈旧,但我认为仍然具有基本的权利:http://www.space.net/~gert/RIPE/ipv6-filters.html

评论


请注意,页面上的Juniper示例当前存在错误(即不匹配正确的前缀)。参见networkengineering.stackexchange.com/a/384/59

–塞巴斯蒂安·维辛格
13年5月29日在8:39

#5 楼

如果要进行“深层”过滤,可以查看团队cymru模板和bogons项目:

http://www.team-cymru.org/ipv6-router-reference。 html