Site-to-Site VPN - Githubissues

freewil commented 4 years ago
I'm wondering if there is any interest in adding support for creating a Site-to-Site VPN? This should be fairly common if you want to connect a remote network to a AWS VPC, for example.
This would require adding support for resources such as ipsec policies, proposals, interfaces, etc. Here is an example configuration for a site-to-site vpn provided by aws:
! Amazon Web Services
! Virtual Private Cloud

! AWS utilizes unique identifiers to manipulate the configuration of
! a VPN Connection. Each VPN Connection is assigned an identifier and is
! associated with two other identifiers, namely the
! Customer Gateway Identifier and Virtual Private Gateway Identifier.
!
! Your VPN Connection ID                  : X
! Your Virtual Private Gateway ID         : X
! Your Customer Gateway ID        : X
!
!
! This configuration consists of two tunnels. Both tunnels must be
! configured on your Customer Gateway.
!

! --------------------------------------------------------------------------------
! IPSec Tunnel #1
! --------------------------------------------------------------------------------
! #1: Internet Key Exchange (IKE) Configuration
!
! A policy is established for the supported ISAKMP encryption,
! authentication, Diffie-Hellman, lifetime, and key parameters.
! Please note, these sample configurations are for the minimum requirement of AES128, SHA1, and DH Group 2.
! Category "VPN" connections in the GovCloud region have a minimum requirement of AES128, SHA2, and DH Group 14.
! You will need to modify these sample configuration files to take advantage of AES256, SHA256, or other DH groups like 2, 14-18, 22, 23, and 24.
! NOTE: If you customized tunnel options when creating or modifying your VPN connection, you may need to modify these sample configurations to match the custom settings for your tunnels.
!
! Higher parameters are only available for VPNs of category "VPN," and not for "VPN-Classic".
! The address of the external interface for your customer gateway must be a static address.
! Your customer gateway may reside behind a device performing network address translation (NAT).
! To ensure that NAT traversal (NAT-T) can function, you must adjust your firewall !rules to unblock UDP port 4500. If not behind NAT, we recommend disabling NAT-T.
!
! Note that there are a global list of ISAKMP policies, each identified by
! sequence number. This policy is defined as #200, which may conflict with
! an existing policy using the same number. If so, we recommend changing
! the sequence number to avoid conflicts.
!

crypto ikev1 enable 'outside_interface' 

crypto ikev1 policy 200
  encryption aes 
  authentication pre-share
  group 2
  lifetime 28800
  hash sha

! --------------------------------------------------------------------------------      
! #2: IPSec Configuration
!
! The IPSec transform set defines the encryption, authentication, and IPSec
! mode parameters.
! Category "VPN" connections in the GovCloud region have a minimum requirement of AES128, SHA2, and DH Group 14.
! Please note, you may use these additionally supported IPSec parameters for encryption like AES256 and other DH groups like 2, 5, 14-18, 22, 23, and 24.
! Higher parameters are only available for VPNs of category "VPN," and not for "VPN-Classic".
!
crypto ipsec ikev1 transform-set ipsec-prop-X-0 esp-aes  esp-sha-hmac

! The IPSec profile references the IPSec transform set and further defines
! the Diffie-Hellman group and security association lifetime.
!
crypto ipsec profile ipsec-vpn-X-0
  set pfs group2
  set security-association lifetime seconds 3600
  set ikev1 transform-set ipsec-prop-vpn-X-0
exit

! Additional parameters of the IPSec configuration are set here. Note that
! these parameters are global and therefore impact other IPSec
! associations.
! This option instructs the router to clear the "Don't Fragment"
! bit from packets that carry this bit and yet must be fragmented, enabling
! them to be fragmented. 
!
!You will need to replace the outside_interface with the interface name of your ASA Firewall.

crypto ipsec df-bit clear-df 'outside_interface'

! This option causes the firewall to reduce the Maximum Segment Size of
! TCP packets to prevent packet fragmentation.

sysopt connection tcpmss 1379

! This configures the gateway's window for accepting out of order
! IPSec packets. A larger window can be helpful if too many packets
! are dropped due to reordering while in transit between gateways.
!
crypto ipsec security-association replay window-size 128

! This option instructs the router to fragment the unencrypted packets
! (prior to encryption).
!You will need to replace the outside_interface with the interface name of your ASA Firewall.
!
crypto ipsec fragmentation before-encryption 'outside_interface'

! --------------------------------------------------------------------------------

! The tunnel group sets the Pre Shared Key used to authenticate the 
! tunnel endpoints.
!
tunnel-group 0.0.0.0 type ipsec-l2l
tunnel-group 0.0.0.0 ipsec-attributes
   ikev1 pre-shared-key <shared_key>
!
! This option enables IPSec Dead Peer Detection, which causes semi-periodic
! messages to be sent to ensure a Security Association remains operational.
!
   isakmp keepalive threshold 10 retry 10
exit

! --------------------------------------------------------------------------------
! #3: Tunnel Interface Configuration
!
! A tunnel interface is configured to be the logical interface associated
! with the tunnel. All traffic routed to the tunnel interface will be
! encrypted and transmitted to the VPC. Similarly, traffic from the VPC
! will be logically received on this interface.
!
! Association with the IPSec security association is done through the
! "tunnel protection" command.
!
! The address of the interface is configured with the setup for your
! Customer Gateway.  If the address changes, the Customer Gateway and VPN
! Connection must be recreated with Amazon VPC.
!
!You will need to replace the outside_interface with the interface name of your ASA Firewall.

interface Tunnel1
  nameif Tunnel-int-vpn-X-0     
  ip address 169.254.251.126 255.255.255.252
  tunnel source interface 'outside_interface'
  tunnel destination 0.0.0.0
  tunnel mode ipsec ipv4
  tunnel protection ipsec profile ipsec-vpn-X-0
  no shutdown
exit

! --------------------------------------------------------------------------------

! #4: Border Gateway Protocol (BGP) Configuration
!
! BGP is used within the tunnel to exchange prefixes between the
! Virtual Private Gateway and your Customer Gateway. The Virtual Private Gateway
! will announce the prefix corresponding to your VPC.
!
! Your Customer Gateway may announce a default route (0.0.0.0/0),
! which can be done with the 'network' and 'default-originate' statements.
!
! The BGP timers are adjusted to provide more rapid detection of outages.
!
! The local BGP Autonomous System Number (ASN) (65000) is configured
! as part of your Customer Gateway. If the ASN must be changed, the
! Customer Gateway and VPN Connection will need to be recreated with AWS.
!
router bgp 65000
  address-family ipv4 unicast
    neighbor 169.254.251.125 remote-as 64512
    neighbor 169.254.251.125 timers 10 30 30
    neighbor 169.254.251.125 default-originate
    neighbor 169.254.251.125 activate

! To advertise additional prefixes to Amazon VPC, copy the 'network' statement
! and identify the prefix you wish to advertise. Make sure the prefix is present
! in the routing table of the device with a valid next-hop.
    network 0.0.0.0
    no auto-summary
    no synchronization
  exit-address-family
exit
!
CiscoDevNet / terraform-provider-ciscoasa

Site-to-Site VPN #35
