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    IPSEC with NAT

    IPsec
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    • H
      huiqbal
      last edited by

      We are trying to connect to one of our client using IPSEC tunnel but with no luck. We have the following configuration.

      Client Network <-> Client VPN Server <===========> Our pfsense Server <-> Our Internal machine
        Linux                  CISCO 7206/IOS 12.1                            pfsense                      Linux               
      B.B.B.B/y                A.A.A.A                                          C.C.C.C                    10.1.1.30

      The Client has a requirement that both pfsense and Our internal machine should have official IP's (no private IP's), but they said 1:1 NAT should work. We gave our internal machine a private IP and using pfsense to do 1:1 NAT. We asked the client to debug on their Cisco VPN switch and see what messages they are seeing when we try to create a tunnel. The client is telling us that they see our  internal IP (10.1.1.30) and not the official IP D.D.D.D as described below. Below is the configuration we have received from our client and the way we have confiured it on our pfsense machine. Any help would be appreciated.

      Configuration received from the Client to open a tunnel.

      Client Public IP Adress: A.A.A.A
      Accessible Client network (public): B.B.B.B/Y
      our VPN public IP Address: C.C.C.C (our pfsense box)
      our Machine running Linux : D.D.D.D
      Encryption: ESP- 3DES with MD5
      DH Group: 3DES Group 2 (1024 bit prime)
      Vendor Id: Disabled
      Perfect Forward Secrecy: disabled
      Compression: disabled
      IKE SA lifetime: 86400 seconds
      IPSEC SA Lifetime: 7200 seconds
      PSK : Customer PSK Key

      Our Pfsense configration,

      Interface: WAN
      Local subnet : single host, D.D.D.D
      Remote subnet:  B.B.B.B/Y
      Remote gateway: A.A.A.A
      Negotiation mode: aggressive

      Phase1:
      My identifier: my IP Address
      Encryption algorithm: 3DES
      Hash Algorithm: MD5
      DH Key group: 2
      Lifetime: 86400
      Authentication method: PSK : Customer PSK key

      Phase 2:
      Protocol: ESP
      Encryption: 3DES
      Hash Algorithm: MD5
      PFS key group: off
      Lifetime: 7200

      We have 1:1 NAT  enabled such that D.D.D.D is mapped to 10.1.1.30.
      The problem is if we set Local subnet : single host, D.D.D.D then on the client side they don't see any activity but if we change it to 10.1.1.30 then Client side see some activity but they are seeing 10.1.1.30 on the CISCO router on their side and it drops the tunnel.
      We spoke with their tech support they are saying some how our 1:1 NAT is sending internal IP and not our D.D.D.D

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      • S
        sullrich
        last edited by

        Please test http://www.pfsense.com/~sullrich/1.0-SNAPSHOT-09-20-06/ which includes NAT-T support.

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        • H
          huiqbal
          last edited by

          No luck even after upgrading to the latest pfSense-Full-Update-1.0-SNAPSHOT-09-20-06. Same errors. Below is the error log.

          Sep 21 18:52:54 racoon: ERROR: unknown notify message, no phase2 handle found.
          Sep 21 18:52:54 racoon: INFO: initiate new phase 2 negotiation: C.C.C.C[500]<=>A.A.A.A[500]
          Sep 21 18:52:53 racoon: INFO: ISAKMP-SA established C.C.C.C[500]-A.A.A.A[500] spi❌x
          Sep 21 18:52:53 racoon: NOTIFY: couldn't find the proper pskey, try to get one by the peer's address.
          Sep 21 18:52:53 racoon: INFO: begin Aggressive mode.
          Sep 21 18:52:53 racoon: INFO: initiate new phase 1 negotiation: C.C.C.C[500]<=>A.A.A.A[500]
          Sep 21 18:52:53 racoon: INFO: IPsec-SA request for 194.39.131.167 queued due to no phase1 found.
          Sep 21 18:52:52 racoon: INFO: 10.1.1.1[500] used for NAT-T
          Sep 21 18:52:52 racoon: INFO: 10.1.1.1[500] used as isakmp port (fd=21)
          Sep 21 18:52:52 racoon: INFO: x%nve0[500] used as isakmp port (fd=20)
          Sep 21 18:52:52 racoon: ERROR: failed to bind to address C.C.C.C[500] (Address already in use).
          Sep 21 18:52:52 racoon: INFO: x%rl0[500] used as isakmp port (fd=19)
          Sep 21 18:52:52 racoon: INFO: x%rl1[500] used as isakmp port (fd=18)
          Sep 21 18:52:52 racoon: INFO: 127.0.0.1[500] used for NAT-T
          Sep 21 18:52:52 racoon: INFO: 127.0.0.1[500] used as isakmp port (fd=17)
          Sep 21 18:52:52 racoon: INFO: ::1[500] used as isakmp port (fd=16)
          Sep 21 18:52:52 racoon: INFO: x::1%lo0[500] used as isakmp port (fd=15)
          Sep 21 18:52:52 racoon: INFO: C.C.C.C[500] used for NAT-T
          Sep 21 18:52:52 racoon: INFO: C.C.C.C[500] used as isakmp port (fd=14)
          Sep 21 18:52:52 racoon: INFO: x%ng1[500] used as isakmp port (fd=13)
          Sep 21 18:52:52 racoon: INFO: @(#)This product linked OpenSSL 0.9.7e-p1 25 Oct 2004 (http://www.openssl.org/)
          Sep 21 18:52:52 racoon: INFO: @(#)ipsec-tools 0.6.6 (http://ipsec-tools.sourceforge.net)

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          • H
            hoba
            last edited by

            Have a look at http://doc.m0n0.ch/handbook-single/#id2608349 . Maybe you find something obvious by viewing this howto.

            1 Reply Last reply Reply Quote 0
            • B
              buraglio
              last edited by

              Did the nat-t stuff get removed from the snapshots?

              nb

              https://www.forwardingplane.net/

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              • S
                sullrich
                last edited by

                Yeah

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                • B
                  buraglio
                  last edited by

                  @sullrich:

                  Yeah

                  ok, good to know. 
                  Thanks

                  nb

                  https://www.forwardingplane.net/

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                  • H
                    huiqbal
                    last edited by

                    I guess since nothing worked for us we should assume NAT-T is not fully functional. We ended up adding an additional NIC to our pfsense machine and bridging it with WAN to assign the official IP to our internal server. We are hoping that soon pfsense will have NAT-T support and we should be able to utilize it.
                    Thanks for everyone's help and goodluck!

                    1 Reply Last reply Reply Quote 0
                    • S
                      sullrich
                      last edited by

                      NAT-T will not be included in 1.0.

                      Maybe 1.1 or in the future.

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