A Role for managing setup and configuration of VPN tunnels.
Basic usage:
all:
hosts:
bastion1.example.com: {...}
bastion2.example.com: {...}
bastion3.example.com: {...}
vars:
vpn_connections:
- hosts:
bastion1.example.com:
bastion2.example.com:
bastion3.example.com:The role will set up a vpn tunnel between each pair of hosts in the list of vpn_connections, using the default parameters, including generating keys as needed. This role assumes that the names of the hosts under hosts are the same as the names of the hosts used in the Ansible inventory, and that you can use those names to configure the tunnels (i.e. they are real FQDNs that resolve correctly).
The exception to the above is when you define a hostname variable under any given host, containing an FQDN, in which case the role will assume this is a managed host and won't attempt to make any changes to it (more details in hosts)
The Ansible controller requires the python ipaddress package on EL7 systems,
or other systems that use python 2.7. On python 3.x systems, the VPN role
uses the python3 built-in ipaddress module.
The role requires the firewall role and the selinux role from the
fedora.linux_system_roles collection, if vpn_manage_firewall and
vpn_manage_selinux are set to true, respectively. (Please see also the
variables in the Firewall and Selinux section.) The
role requires additional collections to manage rpm-ostree systems.
If using the vpn role from the fedora.linux_system_roles collection or from
the Fedora RPM package, the requirements are already satisfied.
Otherwise, please run the following command line to install the collections.
ansible-galaxy collection install -r meta/collection-requirements.ymlThese global variables should be applied to the configuration for every tunnel (unless the user overrides them in the configuration of a particular tunnel).
| Parameter | Description | Type | Required | Default |
|---|---|---|---|---|
| vpn_provider | VPN provider used (e.g. libreswan, wireguard, etc.) | str | no | libreswan |
| vpn_auth_method | VPN authentication method used. | str | no | psk |
| vpn_regen_keys | Whether pre-shared keys should be regenerated for sets of hosts with existing keys. | bool | no | false |
| vpn_opportunistic | Whether an opportunistic mesh configuration should be used. | bool | no | false |
| vpn_default_policy | The default policy group to add target machines to under a mesh configuration. | str | no | private-or-clear |
| vpn_ensure_openssl | Ensure the openssl package is installed on the controller. |
bool | no | true |
| vpn_connections | List of VPN connections to make. | list | yes | - |
The value specified in this variable will determine the value of the authby field for the Libreswan tunnels opened.
Acceptable values:
pskfor pre-shared key (PSK) authenticationcertfor authentication using certificates
The role uses openssl to generate PSKs. It requires this to be installed on the controller node.
The default value is true. If you have pre-generated your PSKs, or you are not using PSKs, then
set vpn_ensure_openssl: false. You can also define the PSKs using the shared_key_content variable in a host in any given tunnel.
vpn_connections is a list of connections. Each connection is either:
-
A list of hosts specified by
hosts. In this host-to-host use case, the role creates tunnels between each pair of hosts. At least one tunnel must be defined in this list. If a single tunnel is required, you only need to specify the remote side. -
A mesh configuration consisting of one or more subnets and profiles. In this mesh use case, the role deploys an opportunistic mesh configuration using the
policy/cidrpairs that you define in thepolicies.
In addition to the global variables, you may provide a number of other variables that will be applied to the configuration for each tunnel.
NOTE All time fields (for example ikelifetime and others) accept the time as a number + unit e.g. 13h for 13 hours, 10s for 10 seconds.
| Parameter | Description | Type | Required | Default | Libreswan Equivalent |
|---|---|---|---|---|---|
| name | A unique, arbitrary name used to prefix the connection name. | str | no | See name | conn <name> |
| hosts | A VPN tunnel will be constructed between each pair of hosts in this dictionary. | dict | yes | - | - |
| auth_method | Authentication method to be used for this connection. | str | no | vpn_auth_method | authby |
| auto | What operation, if any, should be done automatically at startup. | str | no | - | auto |
| opportunistic | Whether an opportunistic mesh configuration should be used. | bool | no | vpn_opportunistic | - |
| policies | List of policy settings to use for an opportunistic mesh configuration. | list | no | - | - |
| shared_key_content | A pre-defined PSK. If not defined, the role will generate one using openssl. IMPORTANT: It is strongly suggested that you do not use this parameter, and instead let the role generate the values. If you must use this, do not set a string in your inventory, but instead read this from a Vault. Also, the PSK will be visible while running in verbose or debug mode. |
str | no | - | PSK from ipsec.secrets file |
| ike | IKE encryption/authentication algorithm to be used for the connection (phase 1 aka ISAKMP SA). NOTE Do not set this unless you must, or really know what you are doing | str | no | - | ike |
| esp | Specifies the algorithms that will be offered/accepted for a Child SA negotiation. NOTE Do not set this unless you must, or really know what you are doing | str | no | - | esp |
| type | The type of the connection. See the libreswan docs for the possible values | str | no | tunnel | type |
| ikelifetime | How long the keying channel of a connection (buzzphrase: "IKE SA" or "Parent SA") should last before being renegotiated. | str | no | - | ikelifetime |
| salifetime | How long a particular instance of a connection (a set of encryption/authentication keys for user packets) should last, from successful negotiation to expiry. | str | no | - | salifetime |
| retransmit_timeout | How long a single packet, including retransmits of that packet, may take before the IKE attempt is aborted. | str | no | - | retransmit-timeout |
| dpddelay | Set the delay time between Dead Peer Detection (IKEv1 RFC 3706) or IKEv2 Liveness keepalives that are sent for this connection. If this is set, dpdtimeout also needs to be set | str | no | - | dpddelay |
| dpdtimeout | Set the length of time that we will idle without hearing back from our peer. After this period has elapsed with no response and no traffic, we will declare the peer dead, and remove the SA. Set value bigger than dpddelay to enable. If dpdtimeout is set, dpddelay also needs to be set. | str | no | - | dpdtimeout |
| dpdaction | When a DPD enabled peer is declared dead, what action should be taken. See libreswan docs for values. | str | no | - | dpdaction |
| leftupdown | The "updown" script to run to adjust routing and/or firewalling when the status of the connection changes (default ipsec _updown). See below. |
str | no | - | leftupdown |
For the default values, and possible values, of ike, esp, type, et. al., please consult the libreswan documentation. You will usually not need to set these.
By default, the role generates a descriptive name for each tunnel it creates from the perspective of each system. For example, when creating a tunnel between bastion1 and bastion2, the descriptive name of this connection on bastion1 is bastion1-to-bastion2 but on bastion2 the connection is named bastion2-to-bastion1. You may add a prefix to these auto-generated names by specifying a value in the name field.
Optionally, you can define an authentication method to use at the connection level. If auth_method is not defined, the role uses the global variable vpn_auth_method. The value of auth_method, or vpn_auth_method, determines the value of the authby field for the Libreswan tunnel opened for this connection. Acceptable values:
pskfor pre-shared key (PSK) authenticationcertfor authentication using certificates
What operation, if any, should be done automatically at IPsec startup. Currently accepted values are add, ondemand, start, and ignore. The default value is null, which means no automatic startup operation.
By default, the VPN System Role creates a host-to-host tunnel between each pair of nodes specified within a vpn_connection. You can instead configure an opportunistic mesh VPN by setting opportunistic to true, which will include all hosts in the Ansible inventory in the opportunistic mesh configuration.
Note: When configuring an opportunistic mesh VPN using a control node that shares the same CIDR as one or more of mesh CIDRs used for encryption, add a clear policy entry for the control node CIDR in order to prevent an SSH connection loss during the play. See example.
It is best to keep it simple - no arguments with spaces, shell metacharacters, or other characters which require quoting or escaping - it will be difficult to pass them through the various layers of yaml, ansible, jinja, and shell. Example:
leftupdown: ipsec_updown --route yeswill result in the config file
leftupdown="ipsec_updown --route yes"If you need to pass an argument which requires quoting, use single quotes:
leftupdown: ipsec_updown --route 'a quoted route value'will result in the config file
leftupdown="ipsec_updown --route 'a quoted route value'"If you need a custom script, the role does not current have the ability to copy or create a script on the managed host. You'll have to figure
out some way to place the script on the host. Then you can point to the script using the full path, like /usr/local/bin/myscript.
By default, Libreswan runs ipsec_updown --route yes. You can disable that by using leftupdown: null.
In this dictionary, you can set policy rules related to opportunistic encryption. If no policy rules are set, the default policy rule is private-or-clear. To override this default policy rule, see cidr. Note that the default policy does not add a 0.0.0.0/0 entry into a policy file. Instead, individual classless inter-domain routing (CIDR) values are added to policy files based on the CIDRs of the managed nodes. The default policy rule will be applied to CIDRs of all the hosts over which this role is run, unless you specify in this section a different policy rule for the CIDR of a particular managed node or group of managed nodes. If users wish to add a 0.0.0.0/0 entry to a particular policy file, they may add an item to this list where the policy value is the desired policy to be applied, and the CIDR value is 0.0.0.0/0.
| Parameter | Description | Type | Required |
|---|---|---|---|
| policy | A valid policy connection group. | str | no |
| cidr | A valid CIDR to which this policy rule is applied. | str | no |
Valid values are private, private-or-clear, and clear.
In addition to any valid CIDR value, you may specify default in this field to apply the corresponding policy to all hosts that do not fit into one of the other specified policy groups, thereby overriding the default private-or-clear policy rule.
Each key in this dictionary is the unique name of a host. If a host is listed in hosts and not in the inventory file, the host will not be managed by the inventory. In such case, the hostname parameter is required because it is necessary for setting up the local ends of such a tunnel.
If the host key in the hosts list of your inventory is not the fully qualified domain name (FQDN) you want to use, you must use the hostname field under each host in this vpn_connections hosts dictionary to specify the actual FQDN or IP address you want the VPN role to use for setting up the tunnel. If you do not specify hostname, then the role will use ansible_host if defined, or the host key in your hosts list if neither ansible_host nor hostname is defined.
For each host key in this dictionary, the following host-specific parameters can be specified.
| Parameter | Description | Type | Required | Default | Libreswan Equivalent |
|---|---|---|---|---|---|
| hostname | Host name or IP address to use for setting up a VPN connection. | str | no | - | left/right |
| cert_name | Certificate nickname of this host's certificate in the NSS database. (Only used when auth_method is cert) |
str | no | - | leftcert/rightcert |
| subnets | A list of the subnets that should be available via the VPN connection. | list | no | - | leftsubnets/rightsubnets |
| leftid | How the left participant (local) should be identified for authentication. | str | no | the local host FQDN (not the controller) | leftid |
| rightid | How the right participant (remote) should be identified for authentication. | str | no | the remote host FQDN | rightid |
Can hold a host name or IP address. Specified only when overriding host names used by Ansible for SSH. Note that if a host name is specified, it must be fully qualified to ensure that DNS resolution works correctly on host machines. This parameter is required when the host is not part of the inventory list of hosts.
It is assumed that the cert_name provided by the user exists in the IPSec NSS cert database. Users may use the certificate system role to issue these certificates.
To confirm that a connection is successfully loaded:
ipsec status | grep <connectionname>To confirm that a connection is successfully started:
ipsec trafficstatus | grep <connectionname>To verify that a certificate has been imported (requires that the connection has loaded successfully). Note that if the same certificate is used for multiple connections, it may show up in the output for this command, even though there was an error on the connection being checked:
ipsec whack --listcertsIf a connection did not successfully load, it is recommended to run the following command to manually try to add the connection. This will give more specific information indicating why the connection failed to establish:
ipsec auto --add <connectionname>Any errors that may have occurred during the process of loading and starting the connection are in the logs, which can be found in /var/log/pluto.log in RHEL 8, or by issuing the command journalctl -u ipsec in RHEL 7. Since these logs can be verbose and contain old entries, it is generally recommended to try to manually add the connection to obtain log messages from the standard output instead.
The firewall must be configured to allow traffic on 500/UDP, 4500/UDP, and 4500/TCP ports for the IKE, ESP, and AH protocols.
| Parameter | Description | Type | Required | Default |
|---|---|---|---|---|
| vpn_manage_firewall | If true, enable the IPsec ports, 500/UDP, 4500/UDP, and 4500/TCP for the IKE, ESP, and AH protocols using the firewall role. If false, the vpn role does not manage the firewall. |
bool | no | false |
| vpn_manage_selinux | If true, manage the IPsec ports, 500/UDP, 4500/UDP, and 4500/TCP using the selinux role. If false, the vpn role does not manage the selinux. |
bool | no | false |
NOTE: The firewall configuration is prerequisite for managing selinux. If the firewall is not installed, managing selinux policy is skipped.
NOTE: vpn_manage_firewall and vpn_manage_selinux are limited to
adding ports and policy, respectively.
It cannot be used for removing them.
If you want to remove ports and/or, you will need to use the firewall system
role and/or the selinux role directly.
- Host-to-Host (openstack): Specific nodes connecting to each other. Use IPsec for IP failover between these nodes (so all other nodes don't need to be aware of anything happening). Keys are FreeIPA certificates, and pre-shared keys
- Host-to-Host (data centers): Two systems in different data centers communicate encrypted with each other using FreeIPA certificates, and pre-shared keys
- Host-to-Host (one host): One system communicating with an existing system (e.g., cisco) in an other organization that uses pre-shared keys
- Network-to-Network (two routers): One organization router connecting to a second one bringing together two distinct networks. Keys are FreeIPA certificates, and pre-shared keys.
- VPN Remote Access Server / Roadwarrior: One organization router accepting connections from multiple clients. Clients connect to a single router using FreeIPA certificates.
- MESH: node independent configurations. When adding/removing a node, you don't need to reconfigure all other nodes. They all attempt to setup individual host-to-host connections. A PKI is used to authenticate nodes (FreeIPA, potentially in the future DNSSEC)
Note that for a couple of these use cases, you cannot use host-scoped settings (e.g. global settings specified in all.hosts).
This playbook sets up the tunnel bastion_east-to-bastion_west using pre-shared key authentication with keys auto-generated by the system role. Additionally, the local ends of two more tunnels are set up: bastion_east-to-bastion_north and bastion_west-to-bastion_north. In this case, one of the hosts, bastion_north, is external to the inventory e.g. in a remote datacenter, and only the local ends of the tunnels can be set up. The hostname field contains all the information necessary to ensure that the local ends of the tunnel are set up correctly. This also shows the
optional parameters you can specify for the tunnel.
all:
hosts:
bastion_east:
ansible_host: bastion1.example.com
bastion_west:
ansible_host: bastion2.example.com
vars:
vpn_connections:
- ike: aes256-sha2;dh19
esp: aes-sha2_512+sha2_256
ikelifetime: 11h
salifetime: 9h
type: transport
hosts:
bastion_east:
bastion_west:
bastion_north: # not in the hosts list
hostname: 192.168.122.103In this case, the hosts have multiple vpn connections associated with multiple NICs e.g. some OpenStack and OpenShift use cases.
all:
hosts:
bastion_east: {...}
bastion_west: {...}
bastion_north: {...}
vars:
vpn_connections:
- name: control_plane_vpn
hosts:
bastion_east:
hostname: 192.168.122.101 # IP for control plane
bastion_west:
hostname: 192.168.122.102
bastion_north:
hostname: 192.168.122.103
- name: data_plane_vpn
hosts:
bastion_east:
hostname: 10.0.0.1 # IP for data plane
bastion_west:
hostname: 10.0.0.2
bastion_north:
hostname: 10.0.0.3This playbook sets up host-to-host tunnels between each pair of hosts in the list of hosts using certificates for authentication.
hosts:
bastion1.example.com: {...}
bastion2.example.com: {...}
bastion3.example.com: {...}
vars:
vpn_connections:
- name: vpn-tunnel-x
auth_method: cert
auto: start
hosts:
bastion1.example.com:
cert_name: bastion1cert
bastion2.example.com:
cert_name: bastion2cert
bastion3.example.com:
cert_name: bastion3certThis playbook sets up a host-to-host tunnel between the current host in the inventory, and a remote host not managed by Ansible (like an appliance) which requires proper identification. In this example this_host should be manually set with the same name as inventory_hostname. The shared key is the key shared between the hosts.
vars:
vpn_connections:
- auth_method: psk
auto: start
shared_key_content: !vault |
$ANSIBLE_VAULT;1.2;AES256;dev
....
hosts:
this_host:
leftid: idoftheclient
nfsserver:
hostname: nfsserver.example.com
rightid: idoftheserverThis playbook sets up an opportunistic mesh VPN configuration on each host in the list of hosts, using certificates for authentication. In this example, the controller machine shares the same CIDR as both of the target machines (192.168.110.0/24) and has IP address 192.168.110.7. Therefore the controller machine will fall under a private policy which will automatically be created for the CIDR 192.168.110.0/24. To prevent an SSH connection loss during the play, a clear policy for the controller machine has been added to the list of policies. Note that there is also an item in the policies list where the cidr is equal to default. This is because this playbook is overriding the default policy rule to make it private instead of private-or-clear.
hosts:
bastion1.example.com:
cert_name: bastion1cert
bastion2.example.com:
cert_name: bastion2cert
bastion3.example.com:
cert_name: bastion3cert
vars:
vpn_connections:
- opportunistic: true
auth_method: cert
policies:
- policy: private
cidr: default
- policy: private-or-clear
cidr: 192.168.122.0/24
- policy: private
cidr: 192.168.110.0/24
- policy: clear
cidr: 192.168.110.7/32The following global variables will be added. Additionally, pubkey will be added as a valid option under vpn_auth_method to perform public key authentication without certificates (enforces SHA-2).
| Parameter | Description | Type | Required | Default |
|---|---|---|---|---|
| vpn_enc_alg | VPN encryption algorithm to use. See Algorithms section for acceptable values. | str | no | - |
| vpn_auth_alg | VPN authentication algorithm to use. | str | no | SHA-2 |
| vpn_wait | If tasks should wait for the VPN tunnel to be started up. | bool | no | false |
| vpn_public_key_src | Path to file on the controller host containing public key used by default. | str | no | - |
| vpn_public_key_content | Contains the public key used by default for public key authentication without certificates. | str | no | - |
The following variables will be added under the hosts dictionary:
| Parameter | Description | Type | Required | Default | Libreswan Equivalent |
|---|---|---|---|---|---|
| public_key_src | Path to file on the controller host containing public key used by this host. | str | no | - | leftrsasigkey/rightrsasigkey |
| public_key_content | Contains the public key used by this host for public key authentication without certificates. | str | no | - | leftrsasigkey/rightrsasigkey |
shared_key_src indicates the path to a file on the controller host containing a PSK to be copied to the ipsec.secrets file on the managed node.
Notes: It is recommended to not specify a pre-shared key, since the role will automatically generate a secure pre-shared key if none is provided by the user. If the user does wish to provide their own pre-shared key, the recommendation is to vault encrypt the value. See https://docs.ansible.com/ansible/latest/user_guide/vault.html. Also, since it is still unclear how the role will allow users to specific pre-shared keys for each pair of hosts in a tunnel, it is reiterated that users should rely on the role's ability to generate secure pre-shared keys automatically.
public_key_src specifies a path to a file on the controller host containing the public key used by this host for public key authentication without certificates. Otherwise, the user can directly specify the public key for this host by populating public_key_content. public_key_content can also accept a CKAID or nickname for a public key in the NSS database.
Note that public_key_src and public_key_content may also be specified as host-scoped Ansible variables. The variable names in this case will be vpn_public_key_src and vpn_public_key_content.
If neither public_key_src nor public_key_content is populated, the role will generate key pairs for each host.
Minimum acceptable algorithms are AES, MODP2048 and SHA2.
See README-ostree.md
MIT.