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L2TP Server: cant connect from macosx behind nat without some changes to ipsec config
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Description

Hi! Just found an issue, when user behind NAT can't connect to l2tp+ipsec server with right config (posted above), without fixing (adding some options) to /etc/ipsec.d/tunnels/remote-access (posted above, lines that were added marked with ->>> <<<-
Client running MacOS Sierra

  1. macos uses 3des-sha1-modp1024 which is not added to config by default
  2. without specifying rightsubnet=0.0.0.0/0 ipsec could not find child SA. But allowed networks were added to vyos config...

Please, test and confirm.

CONFIG:

vpn {
    ipsec {
        ipsec-interfaces {
            interface eth0.900
        }
        nat-networks {
            allowed-network 10.0.0.0/24 {
            }
            allowed-network 172.16.0.0/20 {
            }
            allowed-network 192.168.0.0/16 {
            }
        }
        nat-traversal enable
    }
    l2tp {
        remote-access {
            authentication {
                local-users {
                    username mihon {
                        password ****************
                    }
                }
                mode local
            }
            client-ip-pool {
                start 192.168.255.1
                stop 192.168.255.254
            }
            ipsec-settings {
                authentication {
                    mode pre-shared-secret
                    pre-shared-secret ****************
                }
            }
            outside-address A.B.C.D
        }
    }

/etc/ipsec.d/tunnels/remote-access:

conn remote-access
  authby=secret
    ->>> installpolicy=yes <<<-
    ->>> type=transport <<<-
  pfs=no
  left=A.B.C.D
  leftprotoport=17/1701
  right=%any
  rightsubnet=vhost:%no,%priv
  ->>> rightsubnet=0.0.0.0/0 <<<-
  auto=add
  ->>> ike=aes256-sha1,3des-sha1-modp1024!  <<<-
  dpddelay=15
  dpdtimeout=45
  dpdaction=clear
  esp=aes256-sha1,3des-sha1!
  rekey=no
  ikelifetime=3600
  keylife=3600

Details

Difficulty level
Easy (less than an hour)
Version
999.201702152137 (default boot)
Why the issue appeared?
Implementation mistake

Event Timeline

gaztel renamed this task from L2TP Server cant connect from macosx without some changes to config to L2TP Server: cant connect from macosx behind nat without some changes to ipsec config.Feb 17 2017, 3:36 PM

I can confirm this. Above mentioned lines not present in my custom build (Version: VyOS 999.201708011131).

Access from Windows 10 / iOS10 not working.

@gaztel can you assign this to me please

@gaztel I modified the pm script responsible for the configuration and verified it with iOS 10.3.3 as I do not have a Mac. Windows 10 is now also able to connect.
https://github.com/c-po/vyatta-ravpn/commit/20b85ddf4777ced900da2a56c25922c190823dd5

@syncer This one is fixed/merged and already working in the nightly builds.

syncer claimed this task.
syncer edited projects, added VyOS 1.2 Crux (VyOS 1.2.0-rc1); removed VyOS 1.2 Crux.
syncer moved this task from Needs Triage to Finished on the VyOS 1.2 Crux (VyOS 1.2.0-rc1) board.