我正在设置一个带有外部/内部防火墙的 AWS VPC，以保护 DMZ 中的主机（对于 Internet->DMZ 和 DMZ->Internet 流量）和本地网络上的主机（对于 DMZ->本地、本地->DMZ） ，以及本地->互联网流量）。由于 OpenBSD 现在有 Xen 驱动程序，因此我创建了两个 OpenBSD 6.1 VM，并根据下图对其进行配置。外部防火墙vegeta可以与互联网正常通信。然而，内部防火墙，布尔玛不能。
如果我在 bulma 上并执行以下操作：
$ telnet 50.194.72.148 80
然后我希望看到 vegeta:xnf3 上的数据包，这是 bulma 的默认路由，但我没有。我可以从 bulma ssh 到 vegeta ，所以数据包正在通过。而且，我的 pf 防火墙规则即使默认情况下阻止所有内容，也会允许流量并记录所有其他故障。但是，pf 没有表现出任何值得注意的失败。我是否只是缺少一些 AWS 配置才能使其正常工作？
bulma 上的路由表：
bulma# route -n show -inet
Routing tables
Internet:
Destination Gateway Flags Refs Use Mtu Prio Iface
default 192.168.15.238 UGS 0 209 - 8 xnf0
224/4 127.0.0.1 URS 0 0 32768 8 lo0
127/8 127.0.0.1 UGRS 0 0 32768 8 lo0
127.0.0.1 127.0.0.1 UHhl 1 22 32768 1 lo0
192.168.15.0/28 192.168.15.14 UCn 2 0 - 4 xnf1
192.168.15.1 0a:8f:0f:99:77:46 UHLc 0 5668 - 3 xnf1
192.168.15.2 0a:8f:0f:99:77:46 UHLc 0 3 - 3 xnf1
192.168.15.14 0a:cb:41:73:83:ca UHLl 0 6052 - 1 xnf1
192.168.15.15 192.168.15.14 UHb 0 0 - 1 xnf1
192.168.15.224/28 192.168.15.228 UCn 2 0 - 4 xnf0
192.168.15.225 0a:28:c7:f3:88:0c UHLc 0 5671 - 3 xnf0
192.168.15.228 0a:15:e5:12:a4:28 UHLl 0 5806 - 1 xnf0
192.168.15.238 0a:c4:41:0e:06:74 UHLch 5 113 - 3 xnf0
192.168.15.239 192.168.15.228 UHb 0 0 - 1 xnf0
bulma 上的 /etc/pf.conf：
dmz_if = "xnf0"
int_if = "xnf1"
icmp_types = "{ echoreq, unreach }"
table <aws_nets> const { 192.168.15.0/24 }
set block-policy return
set skip on lo
block log all
block in quick inet6 all
# Allow ping and path MTU discovery
pass in log inet proto icmp all icmp-type $icmp_types keep state
pass out log on $dmz_if inet proto { udp, icmp } all keep state
# Allow anything on the NAT interface
pass in log on $dmz_if inet from <aws_nets> to any
pass out log on $dmz_if inet from $dmz_if:network to any
# Allow anything on the internal interface
pass out log on $int_if inet from $int_if:network to any
# Nat
match out log on $dmz_if inet from $int_if:network to any \
nat-to ($dmz_if:0)
pass out log on $dmz_if from any to any
# Allow ssh
pass in log on $dmz_if inet proto tcp from $dmz_if:network to \
$dmz_if:0 port = ssh
pass out log on $dmz_if inet proto tcp from $dmz_if:network to \
$dmz_if:network port = ssh
# By default, do not permit remote connections to X11
block return in on ! lo0 proto tcp to port 6000:6010
vegeta 上的 /etc/pf.conf：
ext_if = "xnf0"
dmz_if = "xnf3"
icmp_types = "{ echoreq, unreach }"
table <aws_nets> const { 192.168.15.192/28, 192.168.15.208/28, \
192.168.15.224/28 }
set block-policy return
set skip on lo
block log all
block in quick inet6 all
# Allow ping and path MTU discovery
pass in log inet proto icmp all icmp-type $icmp_types keep state
pass out log on $ext_if inet proto { udp, icmp } all keep state
# Allow anything on the NAT interface
pass in log on $dmz_if inet from <aws_nets> to any
# Nat
match out log on $ext_if inet from $dmz_if:network to any \
nat-to ($ext_if:0)
pass out log on $ext_if from any to any
# Allow ssh
pass in log on $ext_if inet proto tcp from any to \
any port = ssh
pass in log on $dmz_if inet proto tcp from any to \
any port = ssh
pass out log on $dmz_if inet proto tcp from $dmz_if:network to \
$dmz_if:network port = ssh
# By default, do not permit remote connections to X11
block return in on ! lo0 proto tcp to port 6000:6010
答案1
好吧，这完全取决于您观看数据包的接口。 pf 在 xnf0 上运行，并将来自 nat 的所有数据包视为仅来自 xnf3。尝试在 vegeta 上的 xnf3 上运行 iftop 监视器，再次进行测试，看看会发生什么。
# pkg_add -v iftop
# iftop -i xnf3
另请检查您在 bluma 上的路线：
# netstat -rn -f inet
确保您的默认网关设置为 192.168.15.238