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On 2013-10-04, Kerin Millar <kerframil@×××××××××××.uk> wrote: |
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> On 04/10/2013 21:55, Grant Edwards wrote: |
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|
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>> I then add an iptables rule like this: |
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>> |
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>> iptables -A OUTPUT -t mangle -p tcp --dport 80 -j MARK --set-mark 1 |
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I'm about to try adding a second iptables rule to us the nat table to |
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rewrite the source IP address. Something like this: |
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|
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iptables -A POSTROUTING -t nat -o net2 -m mark --mark 1 -j SNAT --to 172.16.1.2 |
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|
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> It would help if you were to also supply the details of: |
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> |
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> * ip -f inet -o a s |
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|
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$ ip -f inet -o a s |
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1: lo inet 127.0.0.1/8 scope host lo |
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2: net0 inet 192.168.8.4/16 brd 192.168.255.255 scope global net0 |
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3: net1 inet 10.0.0.1/8 brd 10.255.255.255 scope global net1 |
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3: net1 inet 192.168.250.1/24 brd 192.168.250.255 scope global net1 |
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3: net1 inet 192.168.1.1/24 brd 192.168.1.255 scope global net1 |
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3: net1 inet 169.254.1.1/16 brd 169.254.255.255 scope global net1 |
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5: net2 inet 172.16.1.2/16 brd 172.16.255.255 scope global net2 |
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|
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> * ip route show table main |
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|
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$ ip route show table main |
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default via 192.168.0.254 dev net0 metric 2 |
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10.0.0.0/8 dev net1 proto kernel scope link src 10.0.0.1 |
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127.0.0.0/8 via 127.0.0.1 dev lo |
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169.254.0.0/16 dev net1 proto kernel scope link src 169.254.1.1 |
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172.16.0.0/16 dev net2 proto kernel scope link src 172.16.1.2 metric 5 |
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192.168.0.0/16 dev net0 proto kernel scope link src 192.168.8.4 |
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192.168.1.0/24 dev net1 proto kernel scope link src 192.168.1.1 |
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192.168.250.0/24 dev net1 proto kernel scope link src 192.168.250.1 |
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|
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> * ip route show table pmain |
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|
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$ ip route show table pmain |
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default via 172.16.0.34 dev net2 metric 2 |
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10.0.0.0/8 dev net1 proto kernel scope link src 10.0.0.1 |
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127.0.0.0/8 via 127.0.0.1 dev lo |
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169.254.0.0/16 dev net1 proto kernel scope link src 169.254.1.1 |
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172.16.0.0/16 dev net2 proto kernel scope link src 172.16.1.2 metric 5 |
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192.168.0.0/16 dev net0 proto kernel scope link src 192.168.8.4 |
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192.168.1.0/24 dev net1 proto kernel scope link src 192.168.1.1 |
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192.168.250.0/24 dev net1 proto kernel scope link src 192.168.250.1 |
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> |
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>> |
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>> Now all TCP packets destined for port 80 are sent to the 172.16 |
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>> gateway, _but_ they're being sent with a 192.168 source address. The |
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>> TCP stack is apparently unaware of the advanced routing tricks and |
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>> thinks that the packets are going out via the 192.168 gateway. |
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>> |
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>> IOW I've succesfully re-routed TCP _packets_ but not the TCP |
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>> _connection_. |
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>> |
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>> How do I tell the TCP stack that it's supposed to use the 172.16 |
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>> inteface/gateway for connections to port 80? |
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> |
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> --Kerin |
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> |
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> |
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-- |
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Grant Edwards grant.b.edwards Yow! ! I'm in a very |
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at clever and adorable INSANE |
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gmail.com ASYLUM!! |
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