Iptables
數據包沒有到達 iptables 的 FILTER 鏈
我有一個我無法弄清楚的問題，我正在嘗試訪問網路伺服器
[RPI]，但數據包永遠不會到達iptablesFILTER鏈我會試著解釋一下：
GW1有公共地址，從埠8080到做 DNAT 是一個用於 LAN192.168.69.14:80
S1的 openVPN 伺服器，並且VPN 是橋接的 在埠上執行的網路伺服器是預設網關，沒有公共地址eth0``tap0
[RPI]``80
GW2``[RPI]GW1 <-----------------> S1 <-----Open VPN tunnel------> [RPI] <--Default route--> GW2 (192.168.69.1) (192.168.69.22) (192.168.69.14 - tap0) (192.168.30.1) (192.168.30.2 - wlan0)現在，一切正常如果我從 到達
[RPI]的網路伺服器S1，GW2或者從 pingGW1通但是如果我嘗試通過
GW1埠上的公共 IP訪問網路伺服器8080，數據包確實到達[RPI]，但消失在iptables.，正如您在此處看到的，還有iptables規則列印如下：Apr 27 18:13:51 WeatherStorm kernel: [11383.698445] TRACE: raw:PREROUTING:rule:3 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=275 DF PROTO=TCP SPT=33136 DPT=80 SEQ=3502183596 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B215BF0000000001030307) Apr 27 18:13:51 WeatherStorm kernel: [11383.874415] TRACE: raw:PREROUTING:policy:4 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=275 DF PROTO=TCP SPT=33136 DPT=80 SEQ=3502183596 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B215BF0000000001030307) Apr 27 18:13:51 WeatherStorm kernel: [11384.051167] TRACE: mangle:PREROUTING:policy:1 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=275 DF PROTO=TCP SPT=33136 DPT=80 SEQ=3502183596 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B215BF0000000001030307) Apr 27 18:13:51 WeatherStorm kernel: [11384.227423] TRACE: nat:PREROUTING:policy:1 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=275 DF PROTO=TCP SPT=33136 DPT=80 SEQ=3502183596 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B215BF0000000001030307) Apr 27 18:13:52 WeatherStorm kernel: [11384.459821] TRACE: raw:PREROUTING:rule:3 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=22576 DF PROTO=TCP SPT=33137 DPT=80 SEQ=671043022 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B215FE0000000001030307) Apr 27 18:13:52 WeatherStorm kernel: [11384.635037] TRACE: raw:PREROUTING:policy:4 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=22576 DF PROTO=TCP SPT=33137 DPT=80 SEQ=671043022 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B215FE0000000001030307) Apr 27 18:13:52 WeatherStorm kernel: [11384.811610] TRACE: mangle:PREROUTING:policy:1 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=22576 DF PROTO=TCP SPT=33137 DPT=80 SEQ=671043022 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B215FE0000000001030307) Apr 27 18:13:52 WeatherStorm kernel: [11384.988901] TRACE: nat:PREROUTING:policy:1 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=22576 DF PROTO=TCP SPT=33137 DPT=80 SEQ=671043022 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B215FE0000000001030307) Apr 27 18:13:54 WeatherStorm kernel: [11386.698855] TRACE: raw:PREROUTING:rule:3 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=276 DF PROTO=TCP SPT=33136 DPT=80 SEQ=3502183596 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B218AD0000000001030307) Apr 27 18:13:54 WeatherStorm kernel: [11386.874488] TRACE: raw:PREROUTING:policy:4 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=276 DF PROTO=TCP SPT=33136 DPT=80 SEQ=3502183596 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B218AD0000000001030307) Apr 27 18:13:54 WeatherStorm kernel: [11387.050505] TRACE: mangle:PREROUTING:policy:1 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=276 DF PROTO=TCP SPT=33136 DPT=80 SEQ=3502183596 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B218AD0000000001030307) Apr 27 18:13:54 WeatherStorm kernel: [11387.228835] TRACE: nat:PREROUTING:policy:1 IN=tap0 OUT= MAC=82:ed:f9:e6:c2:ea:00:0c:42:f5:XX:XX:XX:XX SRC=37.188.XXX.XXX DST=192.168.69.14 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=276 DF PROTO=TCP SPT=33136 DPT=80 SEQ=3502183596 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405360402080A01B218AD0000000001030307)生的：
[root@WeatherStorm tmp]# iptables -L -nv -t raw Chain PREROUTING (policy ACCEPT 5750 packets, 748K bytes) pkts bytes target prot opt in out source destination 27 1620 TRACE tcp -- * * 37.188.XXX.XXX 0.0.0.0/0 270 15120 TRACE icmp -- * * 0.0.0.0/0 0.0.0.0/0 51 3958 TRACE tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 Chain OUTPUT (policy ACCEPT 4768 packets, 911K bytes) pkts bytes target prot opt in out source destination 8 448 TRACE icmp -- * * 0.0.0.0/0 0.0.0.0/0 0 0 TRACE tcp -- * * 0.0.0.0/0 37.188.XXX.XXX混亂：
[root@WeatherStorm tmp]# iptables -L -nv -t mangle Chain PREROUTING (policy ACCEPT 4177 packets, 544K bytes) pkts bytes target prot opt in out source destination Chain INPUT (policy ACCEPT 3661 packets, 374K bytes) pkts bytes target prot opt in out source destination Chain FORWARD (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination Chain OUTPUT (policy ACCEPT 3498 packets, 674K bytes) pkts bytes target prot opt in out source destination Chain POSTROUTING (policy ACCEPT 3498 packets, 674K bytes) pkts bytes target prot opt in out source destinationNAT：
[root@WeatherStorm tmp]# iptables -L -nv -t nat Chain PREROUTING (policy ACCEPT 596 packets, 180K bytes) pkts bytes target prot opt in out source destination Chain INPUT (policy ACCEPT 80 packets, 9600 bytes) pkts bytes target prot opt in out source destination Chain OUTPUT (policy ACCEPT 59 packets, 4443 bytes) pkts bytes target prot opt in out source destination Chain POSTROUTING (policy ACCEPT 59 packets, 4443 bytes) pkts bytes target prot opt in out source destination篩選：
[root@WeatherStorm tmp]# iptables -L -nv -t filter Chain INPUT (policy ACCEPT 23788 packets, 2365K bytes) pkts bytes target prot opt in out source destination Chain FORWARD (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination Chain OUTPUT (policy ACCEPT 23777 packets, 5142K bytes) pkts bytes target prot opt in out source destination知道什麼/哪裡可能是問題嗎？如果我嘗試訪問
GW2它看起來像Apr 27 18:22:02 WeatherStorm kernel: [11873.756818] TRACE: raw:PREROUTING:policy:4 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=34259 DF PROTO=TCP SPT=38739 DPT=80 SEQ=3482087833 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F44A0000000001030307) Apr 27 18:22:02 WeatherStorm kernel: [11873.850894] TRACE: mangle:PREROUTING:policy:1 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=34259 DF PROTO=TCP SPT=38739 DPT=80 SEQ=3482087833 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F44A0000000001030307) Apr 27 18:22:02 WeatherStorm kernel: [11873.945646] TRACE: nat:PREROUTING:policy:1 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=34259 DF PROTO=TCP SPT=38739 DPT=80 SEQ=3482087833 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F44A0000000001030307) Apr 27 18:22:02 WeatherStorm kernel: [11874.039622] TRACE: mangle:INPUT:policy:1 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=34259 DF PROTO=TCP SPT=38739 DPT=80 SEQ=3482087833 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F44A0000000001030307) Apr 27 18:22:02 WeatherStorm kernel: [11874.133002] TRACE: filter:INPUT:policy:1 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=34259 DF PROTO=TCP SPT=38739 DPT=80 SEQ=3482087833 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F44A0000000001030307) Apr 27 18:22:02 WeatherStorm kernel: [11874.226404] TRACE: nat:INPUT:policy:1 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=34259 DF PROTO=TCP SPT=38739 DPT=80 SEQ=3482087833 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F44A0000000001030307) Apr 27 18:22:02 WeatherStorm kernel: [11874.319744] TRACE: raw:PREROUTING:policy:4 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=22857 DF PROTO=TCP SPT=38740 DPT=80 SEQ=3524767168 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F4890000000001030307) Apr 27 18:22:02 WeatherStorm kernel: [11874.413794] TRACE: mangle:PREROUTING:policy:1 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=22857 DF PROTO=TCP SPT=38740 DPT=80 SEQ=3524767168 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F4890000000001030307) Apr 27 18:22:02 WeatherStorm kernel: [11874.508565] TRACE: nat:PREROUTING:policy:1 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=22857 DF PROTO=TCP SPT=38740 DPT=80 SEQ=3524767168 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F4890000000001030307) Apr 27 18:22:02 WeatherStorm kernel: [11874.602511] TRACE: mangle:INPUT:policy:1 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=22857 DF PROTO=TCP SPT=38740 DPT=80 SEQ=3524767168 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F4890000000001030307) Apr 27 18:22:04 WeatherStorm kernel: [11874.695929] TRACE: filter:INPUT:policy:1 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=22857 DF PROTO=TCP SPT=38740 DPT=80 SEQ=3524767168 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F4890000000001030307) Apr 27 18:22:04 WeatherStorm kernel: [11874.789331] TRACE: nat:INPUT:policy:1 IN=wlan0 OUT= MAC=a0:f3:c1:2f:86:6a:00:1c:bf:8e:XX:XX:XX:XX SRC=192.168.30.1 DST=192.168.30.2 LEN=60 TOS=0x00 PREC=0x00 TTL=64 ID=22857 DF PROTO=TCP SPT=38740 DPT=80 SEQ=3524767168 ACK=0 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A01B3F4890000000001030307).
解決方案：
解決了以下
iptables規則S1iptables -A PREROUTING -t mangle -i br0 -p tcp --dport 80 -d 192.168.69.14 -j MARK --set-mark 1 iptables -A POSTROUTING -t nat --match mark --mark 1 -j SNAT --to-source 192.168.69.1
您的路由配置
[RPI]不正確 - 如果您希望它可以從公共 Internet 地址通過 訪問GW1，則預設路由必須指向GW1，或者（如果從公共 Internet 地址的傳出連接[RPI]必須通過GW2）您需要在 上配置策略路由[RPI]，以便屬於傳入連接的數據包通過GW1路由GW1。（第三個選項是將數據包
GW1也SNAT發送到192.168.69.1，以便它們[RPI]來自直接連接的 IP，但在這種情況下，您在處理這些數據包時將無法確定實際的客戶端地址[RPI]。對於 HTTP，您可以工作通過安裝反向 HTTP 代理GW1而不是使用 NAT 並在 HTTP 標頭中傳遞真實的客戶端 IP 來解決此問題。）在您目前的配置中，來自
tap0不來自直接連接主機的數據包可能會由於rp_filter在該介面上啟用而被丟棄（儘管根據ip-sysctl.txt，預設值為rp_filter0，許多發行版預設啟用它他們的網路配置）。如果您查看netfilter 數據包流程圖，rp_filter則應用於“路由決策”節點，這與您的觀察結果一致（您看到的最後一個節點是nat:PREROUTING，就在“路由決策”節點之前）。請注意，僅禁用
rp_filter對您沒有幫助，因為來自的回複數據包[RPI]將僅通過 發送GW2，即使它們會以某種方式到達另一台主機，它也會拒絕它們，因為這些數據包不會通過 對它們進行適當的 NAT 處理GW1。您確實必須確保將通過GW1的 NAT 數據包的回復發送回GW1- 沒有此 NAT 將無法正常工作。