Estou tendo um problema com o iptables e uma VPN PPTP, li tópicos relacionados, tanto em ouvir como on-line, mas ainda não consegui fazê-lo funcionar! Eu estou tentando configurar o PPTP em um servidor Ubuntu na nossa rede local, para forçar os clientes a fazer o login através da VPN para obter acesso à Internet. O servidor Ubuntu está conectado diretamente à internet.
No meu rc.local eu tenho o seguinte para encaminhar e aceitar gre
# PPTP IP forwarding
sudo iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
sudo iptables -A INPUT -p gre -j ACCEPT
sudo iptables -A OUTPUT -p gre -j ACCEPT
Isso aparece no meu iptables na lista, então eu sei que está lá.
Eu uso o CSF no servidor como meu firewall, se estiver desabilitado, posso conectar-me à VPN e navegar pela Internet, se o CSF estiver habilitado, eu ser "desconectado pelo dispositivo de comunicação" ou posso conectar, mas tenho sem acesso à internet através da VPN.
Isso também tem o estranho problema de que de vez em quando ele parece funcionar através do firewall!
Eu tenho as seguintes portas abertas:
TCP_IN = ...47,53,80,92,110,143,443,465,587,993,995,1723,7777..
TCP_OUT = ...47,53,80,92,110,113,443,1723,25565,7777...
UDP_IN = 20,21,47,53,1723,27015,27025
UDP_OUT = 20,21,47,53,113,123,1723,27015, 27025
Você tem alguma recomendação sobre como corrigir esse problema? Você precisa de mais informações?
Muito obrigado pelo seu tempo,
Informações extras conforme solicitado:
iptables -nvL
Chain INPUT (policy DROP 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
7377 749K LOCALINPUT all -- !lo * 0.0.0.0/0 0.0.0.0/0
5631 786K ACCEPT all -- lo * 0.0.0.0/0 0.0.0.0/0
0 0 ACCEPT udp -- !lo * 130.88.13.7 0.0.0.0/0 udp spts:1024:65535 dpt:53
0 0 ACCEPT tcp -- !lo * 130.88.13.7 0.0.0.0/0 tcp spts:1024:65535 dpt:53
3 626 ACCEPT udp -- !lo * 130.88.13.7 0.0.0.0/0 udp spt:53 dpts:1024:65535
0 0 ACCEPT tcp -- !lo * 130.88.13.7 0.0.0.0/0 tcp spt:53 dpts:1024:65535
0 0 ACCEPT udp -- !lo * 130.88.13.7 0.0.0.0/0 udp spt:53 dpt:53
0 0 ACCEPT udp -- !lo * 130.88.149.93 0.0.0.0/0 udp spts:1024:65535 dpt:53
0 0 ACCEPT tcp -- !lo * 130.88.149.93 0.0.0.0/0 tcp spts:1024:65535 dpt:53
431 71632 ACCEPT udp -- !lo * 130.88.149.93 0.0.0.0/0 udp spt:53 dpts:1024:65535
0 0 ACCEPT tcp -- !lo * 130.88.149.93 0.0.0.0/0 tcp spt:53 dpts:1024:65535
0 0 ACCEPT udp -- !lo * 130.88.149.93 0.0.0.0/0 udp spt:53 dpt:53
5021 561K INVALID tcp -- !lo * 0.0.0.0/0 0.0.0.0/0
4255 519K ACCEPT all -- !lo * 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:20
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:21
1 64 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:22
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:25
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:47
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:53
61 3648 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:80
1 64 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:92
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:110
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:143
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:389
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:443
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:465
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:587
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:993
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:995
3 192 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:1723
2 128 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:7777
89 5340 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:25565
84 5040 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:27015
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:21433
103 6180 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:25566
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:23456
0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:6667
0 0 ACCEPT udp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:20
0 0 ACCEPT udp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:21
0 0 ACCEPT udp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:47
0 0 ACCEPT udp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:53
0 0 ACCEPT udp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:1723
435 19275 ACCEPT udp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:27015
389 16837 ACCEPT udp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:27025
0 0 ACCEPT udp -- !lo * 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:6667
2 122 ACCEPT icmp -- !lo * 0.0.0.0/0 0.0.0.0/0 icmp type 8 limit: avg 1/sec burst 5
0 0 ACCEPT icmp -- !lo * 0.0.0.0/0 0.0.0.0/0 icmp type 0 limit: avg 1/sec burst 5
0 0 ACCEPT icmp -- !lo * 0.0.0.0/0 0.0.0.0/0 icmp type 11
0 0 ACCEPT icmp -- !lo * 0.0.0.0/0 0.0.0.0/0 icmp type 3
1127 73207 LOGDROPIN all -- !lo * 0.0.0.0/0 0.0.0.0/0
Chain FORWARD (policy DROP 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
Chain OUTPUT (policy DROP 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
8150 710K LOCALOUTPUT all -- * !lo 0.0.0.0/0 0.0.0.0/0
0 0 ACCEPT tcp -- * lo 0.0.0.0/0 0.0.0.0/0 tcp dpt:25
0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:25 owner GID match 8
0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:25 owner UID match 0
123 7380 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:25
5631 786K ACCEPT all -- * lo 0.0.0.0/0 0.0.0.0/0
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 tcp dpt:53
436 32454 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 udp dpt:53
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 tcp spt:53
0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 udp spt:53
6572 649K INVALID tcp -- * !lo 0.0.0.0/0 0.0.0.0/0
6852 636K ACCEPT all -- * !lo 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:20
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:21
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:22
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:25
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:47
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:53
148 8880 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:80
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:92
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:110
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:113
2 120 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:389
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:443
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:1723
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:25565
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:7777
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:27015
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:21433
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:23456
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:3306
30 1800 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:2082
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:92
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:25555
0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:6667
0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:20
0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:21
0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:47
0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:53
0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:113
52 3952 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:123
0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:1723
0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:27015
0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:27025
0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 state NEW udp dpt:6667
0 0 ACCEPT icmp -- * !lo 0.0.0.0/0 0.0.0.0/0 icmp type 0
0 0 ACCEPT icmp -- * !lo 0.0.0.0/0 0.0.0.0/0 icmp type 8
0 0 ACCEPT icmp -- * !lo 0.0.0.0/0 0.0.0.0/0 icmp type 11
0 0 ACCEPT icmp -- * !lo 0.0.0.0/0 0.0.0.0/0 icmp type 3
3 183 LOGDROPOUT all -- * !lo 0.0.0.0/0 0.0.0.0/0
Chain INVALID (2 references)
pkts bytes target prot opt in out source destination
19 844 INVDROP all -- * * 0.0.0.0/0 0.0.0.0/0 state INVALID
0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp flags:0x3F/0x00
0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp flags:0x3F/0x3F
0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp flags:0x03/0x03
0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp flags:0x06/0x06
0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp flags:0x05/0x05
0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp flags:0x11/0x01
0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp flags:0x18/0x08
0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp flags:0x30/0x20
9 360 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp flags:!0x17/0x02 state NEW
Chain INVDROP (10 references)
pkts bytes target prot opt in out source destination
28 1204 DROP all -- * * 0.0.0.0/0 0.0.0.0/0
Chain LOCALINPUT (1 references)
pkts bytes target prot opt in out source destination
0 0 ACCEPT all -- !lo * 10.1.2.0/24 0.0.0.0/0
461 31652 ACCEPT all -- !lo * 78.129.132.155 0.0.0.0/0
6901 714K DSHIELD all -- !lo * 0.0.0.0/0 0.0.0.0/0
6831 695K SPAMHAUS all -- !lo * 0.0.0.0/0 0.0.0.0/0
Chain LOCALOUTPUT (1 references)
pkts bytes target prot opt in out source destination
0 0 ACCEPT all -- * !lo 0.0.0.0/0 10.1.2.0/24
600 32952 ACCEPT all -- * !lo 0.0.0.0/0 78.129.132.155
Chain LOGDROPIN (1 references)
pkts bytes target prot opt in out source destination
0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:67
0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:67
0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:68
0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:68
0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:111
0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:111
0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:113
0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:113
0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpts:135:139
76 18810 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpts:135:139
0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:445
0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:445
0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:500
0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:500
0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:513
0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:513
0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:520
979 50908 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:520
26 1056 LOG tcp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix 'Firewall: *TCP_IN Blocked* '
41 2173 LOG udp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix 'Firewall: *UDP_IN Blocked* '
0 0 LOG icmp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix 'Firewall: *ICMP_IN Blocked* '
72 3489 DROP all -- * * 0.0.0.0/0 0.0.0.0/0
Chain LOGDROPOUT (1 references)
pkts bytes target prot opt in out source destination
0 0 LOG tcp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix 'Firewall: *TCP_OUT Blocked* '
0 0 LOG udp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix 'Firewall: *UDP_OUT Blocked* '
0 0 LOG icmp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix 'Firewall: *ICMP_OUT Blocked* '
3 183 DROP all -- * * 0.0.0.0/0 0.0.0.0/0
iptables -nvL -t nat
pez@brave:~$ sudo iptables -nvL -t nat
Chain PREROUTING (policy ACCEPT 42112 packets, 3106K bytes)
pkts bytes target prot opt in out source destination
Chain POSTROUTING (policy ACCEPT 716 packets, 43090 bytes)
pkts bytes target prot opt in out source destination
0 0 MASQUERADE all -- * * 192.168.122.0/24 !192.168.122.0/24
0 0 MASQUERADE all -- * venet0 10.10.0.0/24 0.0.0.0/0
31176 2345K MASQUERADE all -- * eth0 0.0.0.0/0 0.0.0.0/0
Solução resumida, criado novo arquivo csfpre em / etc / csf / adicionado o seguinte conteúdo:
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
iptables -A INPUT -p gre -j ACCEPT
iptables -A OUTPUT -p gre -j ACCEPT
iptables -A FORWARD -i ppp+ -o eth0 -p ALL -j ACCEPT
iptables -A FORWARD -i eth0 -o ppp+ -p ALL -j ACCEPT