IPSec隧道在第二阶段失效

Question

我们正试图在我们的EC2实例和远程思科3000系列设备之间建立一个隧道，在该设备中，Phase2失败了。以下是设想情况：

FTP服务器(EC2-ubuntu)<->VPN服务器(EC2-ubuntu)<-> Cisco 3000 <-->客户服务器(Ec2)(Ec2)(对等IP) (公共IP)

客户端服务器应通过IPSEC隧道通过弹性IP到达FTP服务器。2.根据客户提供的详细信息，IKE和ESP参数看起来很好。

================IPSEC Configuration START=========
config setup
 nat_traversal=yes
 protostack=netkey
 plutostderrlog=/var/log/pluto.log
 nhelpers=0

 conn example-one
  authby=secret
  auto=start
  type=tunnel
  left=%defaultroute
  leftid=107.23.xx.xx
  leftsourceip=107.23.xx.xx
  leftsubnet=107.23.xxx.xxx/32
  right=144.230.xx.xx
  rightid=144.230.xx.xx
  rightsourceip=144.230.xx.xx
  rightsubnets={144.226.xxx.xx/32 144.226.xxx.xx/32}
  keyexchange=ike
  ike=aes256-sha1;modp1024
  phase2=esp
  phase2alg=aes256-sha1;modp1024
  aggrmode=no
  pfs=no

=============END=================

==========iptables nat rules on VPN Server ======

iptables -t nat -A PREROUTING -d 107.23.xxx.xxx -j DNAT --to-destination 10.0.10.20 
iptables -t nat -A POSTROUTING -d 10.0.10.20 -j SNAT --to-source 107.23.xxx.xxx

10.0.10.20 <<- FTP服务器的私有IP

107.23.xxx.xxx <- FTP服务器的EIP

Belos是我的vpn服务器上的ipsec状态。

000 Total IPsec connections: loaded 1, active 1
000  
000 State Information: DDoS cookies not required, Accepting new IKE connections
000 IKE SAs: total(1), half-open(0), open(0), authenticated(1), anonymous(0)
000 IPsec SAs: total(1), authenticated(1), anonymous(0)
000  
000 #2: "example-one":4500 STATE_QUICK_I2 (sent QI2, IPsec SA established); EVENT_SA_REPLACE in 28045s; newest IPSEC; eroute owner; isakmp#1; idle; import:admin initiate
000 #2: "example-one" esp.69407810@144.230.xxx.xxx esp.27de4982@10.0.10.26 tun.0@144.230.xxx.xxx tun.0@10.0.10.26 ref=0 refhim=4294901761 Traffic: ESPout=0B ESPin=0B! ESPmax=4194303B 
000 #1: "example-one":4500 STATE_MAIN_I4 (ISAKMP SA established); EVENT_SA_REPLACE in 2604s; newest ISAKMP; lastdpd=-1s(seq in:0 out:0); idle; import:admin initiate
000  
000 Bare Shunt list:
000

下面是冥王星日志。

Apr  3 12:44:28: adding interface lo/lo ::1:500
Apr  3 12:44:28: | setup callback for interface lo:500 fd 22
Apr  3 12:44:28: | setup callback for interface lo:4500 fd 21
Apr  3 12:44:28: | setup callback for interface lo:500 fd 20
Apr  3 12:44:28: | setup callback for interface eth0:4500 fd 19
Apr  3 12:44:28: | setup callback for interface eth0:500 fd 18
Apr  3 12:44:28: | setup callback for interface eth0:4500 fd 17
Apr  3 12:44:28: | setup callback for interface eth0:500 fd 16
Apr  3 12:44:28: loading secrets from "/etc/ipsec.secrets"
Apr  3 12:44:28: loading secrets from "/etc/ipsec.d/example.secrets"
Apr  3 12:44:28: "example-one" #1: initiating Main Mode
Apr  3 12:44:28: "example-one" #1: received Vendor ID payload [RFC 3947]
Apr  3 12:44:28: "example-one" #1: received Vendor ID payload [FRAGMENTATION c0000000]
Apr  3 12:44:28: "example-one" #1: enabling possible NAT-traversal with method RFC 3947 (NAT-Traversal)
Apr  3 12:44:28: "example-one" #1: transition from state STATE_MAIN_I1 to state STATE_MAIN_I2
Apr  3 12:44:28: "example-one" #1: STATE_MAIN_I2: sent MI2, expecting MR2
Apr  3 12:44:28: "example-one" #1: received Vendor ID payload [Cisco-Unity]
Apr  3 12:44:28: "example-one" #1: received Vendor ID payload [XAUTH]
Apr  3 12:44:28: "example-one" #1: ignoring unknown Vendor ID payload [5397e372bf085cf3a0b093e1623498c2]
Apr  3 12:44:28: "example-one" #1: ignoring Vendor ID payload [Cisco VPN 3000 Series]
Apr  3 12:44:28: "example-one" #1: NAT-Traversal: Result using RFC 3947 (NAT-Traversal) sender port 500: I am behind NAT
Apr  3 12:44:28: "example-one" #1: transition from state STATE_MAIN_I2 to state STATE_MAIN_I3
Apr  3 12:44:28: "example-one" #1: STATE_MAIN_I3: sent MI3, expecting MR3
Apr  3 12:44:28: "example-one" #1: received Vendor ID payload [Dead Peer Detection]
Apr  3 12:44:28: | protocol/port in Phase 1 ID Payload is 17/0. accepted with port_floating NAT-T
Apr  3 12:44:28: "example-one" #1: Main mode peer ID is ID_IPV4_ADDR: '144.230.xxx.xxx'
Apr  3 12:44:28: "example-one" #1: transition from state STATE_MAIN_I3 to state STATE_MAIN_I4
Apr  3 12:44:28: "example-one" #1: STATE_MAIN_I4: ISAKMP SA established {auth=PRESHARED_KEY cipher=aes_256 integ=sha group=MODP1024}
Apr  3 12:44:28: "example-one" #2: initiating Quick Mode PSK+ENCRYPT+TUNNEL+UP+IKEV1_ALLOW+IKEV2_ALLOW+SAREF_TRACK+IKE_FRAG_ALLOW {using isakmp#1 msgid:effe9287 proposal=AES(12)_256-SHA1(2)_000 pfsgroup=no
-pfs}
Apr  3 12:44:28: "example-one" #2: ignoring informational payload IPSEC_RESPONDER_LIFETIME, msgid=effe9287, length=28
Apr  3 12:44:28: | ISAKMP Notification Payload
Apr  3 12:44:28: |   00 00 00 1c  00 00 00 01  03 04 60 00
Apr  3 12:44:28: "example-one" #2: transition from state STATE_QUICK_I1 to state STATE_QUICK_I2
Apr  3 12:44:28: "example-one" #2: STATE_QUICK_I2: sent QI2, IPsec SA established tunnel mode {ESP/NAT=>0x414c5406 <0x8df53642 xfrm=AES_256-HMAC_SHA1 NATOA=none NATD=144.230.xxx.xxx:4500 DPD=passive} 

下面是tcpdump。

# tcpdump -n -i eth0 esp or udp port 500 or udp port 4500
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
11:58:42.229262 IP 10.0.10.26.ipsec-nat-t > 144.230.xxx.xxx.ipsec-nat-t: isakmp-nat-keep-alive
11:58:42.229280 IP 10.0.10.26.ipsec-nat-t > 144.230.xxx.xxx.ipsec-nat-t: isakmp-nat-keep-alive
11:58:44.487779 IP 144.230.xxx.xxx.ipsec-nat-t > 10.0.10.26.ipsec-nat-t: NONESP-encap: isakmp: phase 2/others ? inf[E]
11:58:44.487986 IP 10.0.10.26.ipsec-nat-t > 144.230.xxx.xxx.ipsec-nat-t: NONESP-encap: isakmp: phase 2/others ? inf[E]

下面是sysctl命令输出。

sysctl -p
net.ipv4.conf.all.rp_filter = 0
net.ipv4.conf.default.rp_filter = 0
net.ipv4.conf.eth0.rp_filter = 0
net.ipv4.conf.lo.rp_filter = 0
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.default.send_redirects = 0
net.ipv4.conf.eth0.send_redirects = 0
net.ipv4.conf.lo.send_redirects = 0
net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.default.accept_redirects = 0
net.ipv4.conf.eth0.accept_redirects = 0
net.ipv4.conf.lo.accept_redirects = 0
net.ipv4.ip_forward = 1 

下面是应用于VPN服务器的iptable规则。

 iptables -t nat --line-numbers -L
Chain PREROUTING (policy ACCEPT)
num  target     prot opt source               destination        
1    DNAT       all  --  anywhere             ec2-107-23-xxx-xxx.compute-1.amazonaws.com  to:10.0.10.20

Chain INPUT (policy ACCEPT)
num  target     prot opt source               destination        

Chain OUTPUT (policy ACCEPT)
num  target     prot opt source               destination        

Chain POSTROUTING (policy ACCEPT)
num  target     prot opt source               destination        
1    SNAT       all  --  anywhere             ip-10-0-10-20.ec2.internal  to:107.23.xxx.xxx
2    MASQUERADE  all  --  anywhere             anywhere

iptables -t nat -A PREROUTING -d 107.23.xxx.xxx -j DNAT --to-destination 10.0.10.20
iptables -t nat -A POSTROUTING -d 10.0.10.20 -j SNAT --to-source 107.23.xxx.xxx

Answer 1

下面是实现此功能的步骤。

1. 您需要用VPN服务器的接口ID更新路由表。以便您的FTP服务器的所有通信通过VPN主机(即{144.226.xx.xxx/32 eniXXXXXX( VPN服务器的接口id ))到达正确的子网。
2. IPSEC配置如下所示

测试您的VPN服务器的authby=secret auto=start type=tunnel left=%defaultroute leftid=10.0.10.30 ####专用IP服务器的左子网=107.23.xx.xxx/32 ###公共IP FTP服务器leftnexthop=%defaultroute right=144.230.xxx.xxx ### Peer IP of Cisco设备rightid=144.230.xxx.xxx ### Peer IP Cisco Device rightnexthop=107.23.XXX.XXX ### E IP VPN服务器的右子网=144.226.xxx.xxx/32 ###右/客户端子网keyexchange=ike ike=256-SHA1；modp1024 phase2=esp phase2alg=ese256-SHA1；sha1 1024 aggrmode=no pfs=no

1. 最后，您需要在防火墙中添加nat规则。iptables -t nat -A PREROUTING -d 107.23.XXX.XXX (FTP服务器IP) -jDNAT --目的地10.0.10.32 (FTP服务器的专用IP) iptables -t nat -A POSTROUTING -s 10.0.10.32 -d 144.26.XXX.XXX (客户端/右侧ip ) -j SNAT -to 107.23.xxx.xxx ( FTP服务器IP)

注意：

1. IPv4转发应该在sysctl.conf中启用。
2. 在秘密文件中使用您的私有ip，即"10.0.10.30(VPN主机专用IP) 144.23.xxx.xxx (Cisco Peer )：“