Acabei de configurar um túnel VPN site a site com strongswan (4.5). O túnel parece bom e conectado ao outro lado, mas parece que há um problema no roteamento de tráfego através do túnel.
Qualquer ideia?
Obrigado!
Diagrama de rede
+----------------------------------+
|Dedicated server: starfleet | +-----------------+
| | | CISCO ASA |
| +-------------------------| internet | |
| |eth0: XX.XX.XX.195/29 +-------------------| YY.YYY.YYY.155 |
| +-------------------------| +------+----------+
| |virbr1: 192.168.100.1/24 | |
| +----+--------------------| |
| | | |
| | | +-----------------+
| | | |network |
| +-------+ | | |
| | | |172.30.20.0/27 |
| | | +-----------------+
| +------------------------------+ |
| | kvm server: enterprise | |
| | | |
| | | |
| | eth0: 192.168.100.100/24 | |
| +------------------------------+ |
+----------------------------------+
Programas
- debian wheezy
- strongswan 4.5.2-1.5 + deb7u1
- kvm e libvirt (rede 192.168.100.x)
/etc/ipsec.conf
root@starfleet ~ # cat /etc/ipsec.conf
# ipsec.conf - strongSwan IPsec configuration file
# basic configuration
config setup
plutodebug="all"
plutostderrlog=/var/log/pluto-ipsec
charonstart=no
plutostart=yes
conn net-net
ikelifetime=86400s
keylife=3600s
rekeymargin=3m
keyingtries=1
keyexchange=ikev1
authby=secret
ike=aes256-sha-modp1024!
esp=aes256-sha
right=YY.YYY.YYY.155
rightsubnet=172.30.20.0/27
left=XX.XX.XX.195
leftsubnet=192.168.100.0/24
leftfirewall=yes
pfs=no
auto=add
Ipsec up
root@starfleet ~ # ipsec up net-net
002 "net-net" #1: initiating Main Mode
102 "net-net" #1: STATE_MAIN_I1: initiate
003 "net-net" #1: ignoring Vendor ID payload [FRAGMENTATION c0000000]
104 "net-net" #1: STATE_MAIN_I2: sent MI2, expecting MR2
003 "net-net" #1: ignoring Vendor ID payload [Cisco-Unity]
003 "net-net" #1: received Vendor ID payload [XAUTH]
003 "net-net" #1: ignoring Vendor ID payload [###############################]
003 "net-net" #1: ignoring Vendor ID payload [Cisco VPN 3000 Series]
106 "net-net" #1: STATE_MAIN_I3: sent MI3, expecting MR3
002 "net-net" #1: Peer ID is ID_IPV4_ADDR: 'YY.YYY.YYY.155'
002 "net-net" #1: ISAKMP SA established
004 "net-net" #1: STATE_MAIN_I4: ISAKMP SA established
002 "net-net" #2: initiating Quick Mode PSK+ENCRYPT+TUNNEL+UP {using isakmp#1}
110 "net-net" #2: STATE_QUICK_I1: initiate
002 "net-net" #2: sent QI2, IPsec SA established {ESP=>0x8a12ab22 <0xa01abba1}
004 "net-net" #2: STATE_QUICK_I2: sent QI2, IPsec SA established {ESP=>0x8a12ab22 <0xa01abba1}
root@starfleet ~ # ipsec status
000 "net-net": 192.168.100.0/24===XX.XX.XX.195[XX.XX.XX.195]...YY.YYY.YYY.155[YY.YYY.YYY.155]===172.30.20. 0/27; erouted; eroute owner: #2
000 "net-net": newest ISAKMP SA: #1; newest IPsec SA: #2;
000
000 #2: "net-net" STATE_QUICK_I2 (sent QI2, IPsec SA established); EVENT_SA_REPLACE in 3331s; newest IPSEC; eroute owner
000 #2: "net-net" [email protected] (0 bytes) [email protected] (0 bytes); tunnel
000 #1: "net-net" STATE_MAIN_I4 (ISAKMP SA established); EVENT_SA_REPLACE in 86050s; newest ISAKMP
000
Informações de rede
A interface tun0 é usada pelo servidor openvpn.
interface virbr1 é uma rede kvm
root@starfleet ~ # ip -4 a s
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
inet 127.0.0.1/8 scope host lo
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
inet XX.XX.XX.195/29 brd XX.XX.XX.199 scope global eth0
3: tun0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 100
inet 10.8.0.1 peer 10.8.0.2/32 scope global tun0
5: virbr1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP
inet 192.168.100.1/24 brd 192.168.100.255 scope global virbr1
root@starfleet ~ # ip -4 r s t 0
default via XX.XX.XX.193 dev eth0
10.8.0.0/16 via 10.8.0.2 dev tun0
10.8.0.2 dev tun0 proto kernel scope link src 10.8.0.1
XX.XX.XX.192/29 via XX.XX.XX.193 dev eth0
XX.XX.XX.192/29 dev eth0 proto kernel scope link src XX.XX.XX.195
192.168.100.0/24 dev virbr1 proto kernel scope link src 192.168.100.1
local 10.8.0.1 dev tun0 table local proto kernel scope host src 10.8.0.1
broadcast XX.XX.XX.192 dev eth0 table local proto kernel scope link src XX.XX.XX.195
local XX.XX.XX.195 dev eth0 table local proto kernel scope host src XX.XX.XX.195
broadcast XX.XX.XX.199 dev eth0 table local proto kernel scope link src XX.XX.XX.195
broadcast 127.0.0.0 dev lo table local proto kernel scope link src 127.0.0.1
local 127.0.0.0/8 dev lo table local proto kernel scope host src 127.0.0.1
local 127.0.0.1 dev lo table local proto kernel scope host src 127.0.0.1
broadcast 127.255.255.255 dev lo table local proto kernel scope link src 127.0.0.1
broadcast 192.168.100.0 dev virbr1 table local proto kernel scope link src 192.168.100.1
local 192.168.100.1 dev virbr1 table local proto kernel scope host src 192.168.100.1
broadcast 192.168.100.255 dev virbr1 table local proto kernel scope link srr 192.168.100.1
root@starfleet ~ # ip xfrm state
src XX.XX.XX.195 dst YY.YYY.YYY.155
proto esp spi 0x8a12ab22 reqid 16384 mode tunnel
replay-window 32 flag af-unspec
auth-trunc hmac(sha1) 0x######################################## 96
enc cbc(aes) 0x################################################################
src YY.YYY.YYY.155 dst XX.XX.XX.195
proto esp spi 0xa01abba1 reqid 16384 mode tunnel
replay-window 32 flag af-unspec
auth-trunc hmac(sha1) 0x######################################## 96
enc cbc(aes) 0x################################################################
root@starfleet ~ # ip xfrm policy
src 192.168.100.0/24 dst 172.30.20.0/27
dir out priority 1847 ptype main
tmpl src XX.XX.XX.195 dst YY.YYY.YYY.155
proto esp reqid 16384 mode tunnel
src 172.30.20.0/27 dst 192.168.100.0/24
dir fwd priority 1847 ptype main
tmpl src YY.YYY.YYY.155 dst XX.XX.XX.195
proto esp reqid 16384 mode tunnel
src 172.30.20.0/27 dst 192.168.100.0/24
dir in priority 1847 ptype main
tmpl src YY.YYY.YYY.155 dst XX.XX.XX.195
proto esp reqid 16384 mode tunnel
src ::/0 dst ::/0
socket out priority 0 ptype main
src ::/0 dst ::/0
socket in priority 0 ptype main
src ::/0 dst ::/0
socket out priority 0 ptype main
src ::/0 dst ::/0
socket in priority 0 ptype main
src 0.0.0.0/0 dst 0.0.0.0/0
socket out priority 0 ptype main
src 0.0.0.0/0 dst 0.0.0.0/0
socket in priority 0 ptype main
src 0.0.0.0/0 dst 0.0.0.0/0
socket out priority 0 ptype main
src 0.0.0.0/0 dst 0.0.0.0/0
socket in priority 0 ptype main
root@starfleet ~ # ip route show table 220
root@starfleet ~ #
root@starfleet ~ # route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 XX.XX.XX.193 0.0.0.0 UG 0 0 0 eth0
10.8.0.0 10.8.0.2 255.255.0.0 UG 0 0 0 tun0
10.8.0.2 0.0.0.0 255.255.255.255 UH 0 0 0 tun0
XX.XX.XX.192 XX.XX.XX.193 255.255.255.248 UG 0 0 0 eth0
XX.XX.XX.192 0.0.0.0 255.255.255.248 U 0 0 0 eth0
192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 virbr1
Iptables
root@starfleet ~ # iptables-save
# Generated by iptables-save v1.4.14 on Fri May 24 16:07:39 2013
*nat
:PREROUTING ACCEPT [11:368]
:INPUT ACCEPT [1:48]
:OUTPUT ACCEPT [13:1012]
:POSTROUTING ACCEPT [13:1012]
-A POSTROUTING -s 10.8.0.0/16 ! -d 10.8.0.0/16 -o virbr1 -j MASQUERADE
-A POSTROUTING -s 192.168.100.0/24 ! -d 192.168.100.0/24 -p tcp -j MASQUERADE --to-ports 1024-65535
-A POSTROUTING -s 192.168.100.0/24 ! -d 192.168.100.0/24 -p udp -j MASQUERADE --to-ports 1024-65535
-A POSTROUTING -s 192.168.100.0/24 ! -d 192.168.100.0/24 -j MASQUERADE
COMMIT
# Completed on Fri May 24 16:07:39 2013
# Generated by iptables-save v1.4.14 on Fri May 24 16:07:39 2013
*mangle
:PREROUTING ACCEPT [271:19504]
:INPUT ACCEPT [261:19184]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [181:28686]
:POSTROUTING ACCEPT [181:28686]
-A POSTROUTING -o virbr1 -p udp -m udp --dport 68 -j CHECKSUM --checksum-fill
COMMIT
# Completed on Fri May 24 16:07:39 2013
# Generated by iptables-save v1.4.14 on Fri May 24 16:07:39 2013
*filter
:INPUT ACCEPT [46:3380]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [36:5220]
-A INPUT -i virbr1 -p udp -m udp --dport 53 -j ACCEPT
-A INPUT -i virbr1 -p tcp -m tcp --dport 53 -j ACCEPT
-A INPUT -i virbr1 -p udp -m udp --dport 67 -j ACCEPT
-A INPUT -i virbr1 -p tcp -m tcp --dport 67 -j ACCEPT
-A FORWARD -s 172.30.20.0/27 -d 192.168.100.0/24 -i eth0 -m policy --dir in --pol ipsec --reqid 16384 --proto esp -j ACCEPT
-A FORWARD -s 192.168.100.0/24 -d 172.30.20.0/27 -o eth0 -m policy --dir out --pol ipsec --reqid 16384 --proto esp -j ACCEPT
-A FORWARD -s 10.8.0.0/16 -o virbr1 -j ACCEPT
-A FORWARD -i virbr1 -o tun0 -m state --state RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -d 192.168.100.0/24 -o virbr1 -m state --state RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -s 192.168.100.0/24 -i virbr1 -j ACCEPT
-A FORWARD -i virbr1 -o virbr1 -j ACCEPT
-A FORWARD -o virbr1 -j REJECT --reject-with icmp-port-unreachable
-A FORWARD -i virbr1 -j REJECT --reject-with icmp-port-unreachable
COMMIT
# Completed on Fri May 24 16:07:39 2013
TcpDumping de 192.168.100.100 para 172.30.20.9
Todos os comandos estão sendo executados ao mesmo tempo.
root@enterprise:~# ping 172.30.20.9
PING 172.30.20.9 (172.30.20.9) 56(84) bytes of data.
^C
--- 172.30.20.9 ping statistics ---
6 packets transmitted, 0 received, 100% packet loss, time 4999ms
root@enterprise:~# tcpdump -v -n dst net 172.30.20.0/27
tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
16:23:48.919819 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.100.100 > 172.30.20.9: ICMP echo request, id 2605, seq 1, length 64
16:23:49.918949 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.100.100 > 172.30.20.9: ICMP echo request, id 2605, seq 2, length 64
16:23:50.918950 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.100.100 > 172.30.20.9: ICMP echo request, id 2605, seq 3, length 64
16:23:51.918952 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.100.100 > 172.30.20.9: ICMP echo request, id 2605, seq 4, length 64
16:23:52.918954 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.100.100 > 172.30.20.9: ICMP echo request, id 2605, seq 5, length 64
16:23:53.918951 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.100.100 > 172.30.20.9: ICMP echo request, id 2605, seq 6, length 64
root@starfleet ~ # tcpdump -v -n dst net 172.30.20.0/27
tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
16:23:50.475100 IP (tos 0x0, ttl 63, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
XX.XX.XX.195 > 172.30.20.9: ICMP echo request, id 2605, seq 1, length 64
16:23:51.474262 IP (tos 0x0, ttl 63, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
XX.XX.XX.195 > 172.30.20.9: ICMP echo request, id 2605, seq 2, length 64
16:23:52.474280 IP (tos 0x0, ttl 63, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
XX.XX.XX.195 > 172.30.20.9: ICMP echo request, id 2605, seq 3, length 64
16:23:53.474251 IP (tos 0x0, ttl 63, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
XX.XX.XX.195 > 172.30.20.9: ICMP echo request, id 2605, seq 4, length 64
16:23:54.474213 IP (tos 0x0, ttl 63, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
XX.XX.XX.195 > 172.30.20.9: ICMP echo request, id 2605, seq 5, length 64
16:23:55.474173 IP (tos 0x0, ttl 63, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
XX.XX.XX.195 > 172.30.20.9: ICMP echo request, id 2605, seq 6, length 64
fonte
Minha situação é muito semelhante à descrita por @telemaco. Eu tenho algumas VMs de teste em execução no KVM no meu laptop. Meu laptop recebe seu endereço IP via DHCP, portanto, o endereço IP do ponto final da VPN é atribuído pelo Strongswan ao meu laptop via
leftsourceip=%config
.As VMs usam uma rede privada
192.168.100.0/24
. Meu laptop (host KVM) recebe o endereço IP192.168.50.2/24
via DHCP e um endereço IP10.0.0.10/26
do terminal da Strongswan.As VMs devem acessar uma rede
192.168.0.0/24
, que é roteada através da VPN.Com base na resposta fornecida por @ecdsa, consegui este trabalho adicionando a seguinte regra:
No meu caso,
ip xfrm policy
fica assim (extrato):Isso significa que apenas o endereço IP local
10.0.0.10
possui umaxfrm lookup
regra correspondente . É por isso que o NAT é necessário, a menos que a sub-rede da VM seja adicionada ao IPsec.fonte