NAME

Net::Firewall::BlockerHelper::backends::vyos - VyOS backend using the HTTP API.

VERSION

Version 0.1.0

SYNOPSIS

use Net::Firewall::BlockerHelper;

my $fw_helper = Net::Firewall::BlockerHelper->new(
    backend => 'vyos',
    name    => 'ssh',
    options => {
        host => '10.0.0.1',
        key  => $vyos_api_key,
    },
);

$fw_helper->init_backend;
$fw_helper->ban( ban => '1.2.3.4' );
$fw_helper->unban( ban => '1.2.3.4' );

DESCRIPTION

Blocks IPs on a VyOS device via its HTTP API, adding and removing entries in a firewall address-group. IPv4 addresses are managed under the config path firewall group address-group <group> address <ip> and IPv6 under firewall group ipv6-address-group <group> address <ip>, using the group name given by the group option (defaulting to <prefix>_<name>).

The VyOS HTTP API takes application/x-www-form-urlencoded POSTs where the body is data=<url-escaped JSON>&key=<apikey>. Configuration changes are POSTed to https://<host>/configure and are auto-committed. The banned addresses are managed only here; a firewall rule referencing the address-group must already exist on the device.

Blocking is per IP; ports and protocols belong on the referencing rule, so specifying them here is an error.

LWP::UserAgent is loaded at run time, so it is only required when this backend is actually used. For https, LWP::Protocol::https must be present as well.

METHODS

new

Initiates the object.

- options :: Backend specific options. See below.
- prefix :: Prefix to use. Must match /^[a-zA-Z0-9]+$/. Default kur.
- name :: Name of this instance. Required.

Ports and protocols are not supported and specifying either is an error.

The options hash accepts the following.

- host :: VyOS host, optionally host:port. Required.
    - Default :: undef

- key :: VyOS HTTP API key. Required.
    - Default :: undef

- group :: Firewall address-group name the banned addresses are added to.
        The same name is used for the IPv4 address-group and the IPv6
        ipv6-address-group.
    - Default :: <prefix>_<name>

- insecure :: If true, skip TLS certificate verification (VyOS ships a
        self-signed certificate).
    - Default :: 0

- timeout :: HTTP timeout in seconds.
    - Default :: 30

All errors are considered fatal, meaning if new fails it will die.

init

Initiates the backend. Verifies the credentials and reachability by POSTing a showConfig operation for the address-group to /retrieve. Nothing is created on the device; the referencing firewall rule must already exist.

$backend->init;

ban

Bans an IP. The value of ban is validated as being a IPv4 or IPv6 address and lowercased, then a set operation for firewall group address-group <group> address <ip> (or the ipv6-address-group equivalent) is POSTed to /configure. Banning an already banned IP is a noop.

$backend->ban(ban => $ip);

unban

Unbans an IP. The value of ban is validated as being a IPv4 or IPv6 address and lowercased, then a delete operation for its address-group entry is POSTed to /configure. Unbanning an IP that is not banned is a noop.

$backend->unban(ban => $ip);

ban_cidr

Bans a CIDR range by POSTing a set operation for it to /configure, adding it to the address-group in the same manner as a single IP. The value of ban is validated as being a IPv4 or IPv6 CIDR range and lowercased. Banning an already banned range is a noop.

$backend->ban_cidr(ban => '1.2.3.0/24');

unban_cidr

Unbans a CIDR range by POSTing a delete operation for its address-group entry to /configure. The value of ban is validated as being a IPv4 or IPv6 CIDR range and lowercased. Unbanning a range that is not banned is a noop.

$backend->unban_cidr(ban => '1.2.3.0/24');

list_cidr

List banned CIDR ranges. Returns an array of the currently banned CIDR ranges. Single IPs are not included; for those see "list".

my @banned_cidrs = $backend->list_cidr;

list

List banned IPs. Returns an array of the currently banned single IPs. CIDR ranges are not included; for those see "list_cidr".

my @banned = $backend->list;

re_init

Tears down and re-inits, then re-adds all previously added bans. teardown is best effort, as a partially or fully wiped setup is what this needs to recover from. Each retained single IP and CIDR ban is re-added via a set operation POSTed to /configure.

$backend->re_init;

teardown

Tears down the setup by deleting the address-group entry for each currently banned IP and CIDR range. The internal list of bans is kept, so a following re_init will re-add them.

stop

Alias for "teardown".

check

Verifies the endpoint and credentials are still usable by retrieving the address-group config. Returns a true value if so and a false value otherwise.

flush

Removes all currently banned IPs and CIDR ranges at once by deleting their address-group entries and forgetting them.

$backend->flush;

ERROR CODES / FLAGS

Error handling is provided by Error::Helper. All errors are considered fatal.

1, notInited

The backend has not been inited yet.

6, invalidPrefixSpecified

The specified prefix did not match /^[a-zA-Z0-9]+$/.

7, invalidName

The name is either undef or does not match /^[a-zA-Z0-9\-]+$/.

8, optionsNotHash

The item passed to new for options is not a hash.

9, noBanItem

No IP or CIDR range specified to ban or unban.

10, banItemNotIP

The item to ban is not an IP. Either wrong ref type or regexp test using Regexp::IPv4 and Regexp::IPv6 failed.

12, backendInitError

Failed to init the backend.

13, banFailed

Failed to ban the item.

14, unbanFailed

Failed to unban the item.

15, listFailed

Failed to get a list of bans.

16, reInitFailed

Failed to re_init the backend.

17, teardownFailed

Failed to teardown the backend.

18, alreadyInited

init called, but the backend has already been inited.

23, initFailed

init failed. Probing the address-group config failed.

24, checkFailed

The backend check raised an error.

25, flushFailed

Failed to flush the bans.

26, portsNotSupported

Ports were specified, but this backend manages whole IPs and does not support ports.

27, protocolsNotSupported

Protocols were specified, but this backend manages whole IPs and does not support protocols.

30, hostNotDefined

The option host is undef or blank.

31, keyNotDefined

The option key is undef or blank.

32, banCidrFailed

Failed to ban the CIDR range.

33, unbanCidrFailed

Failed to unban the CIDR range.

34, cidrItemNotCidr

The item to ban is not a CIDR range. Either wrong ref type or it is not an IPv4 or IPv6 address followed by a prefix length valid for its family.

35, cidrNotSupported

The backend does not support CIDR bans.

36, listCidrFailed

Failed to get a list of CIDR bans.

AUTHOR

Zane C. Bowers-Hadley, <vvelox at vvelox.ent>

LICENSE AND COPYRIGHT

This software is Copyright (c) 2023 by Zane C. Bowers-Hadley.

This is free software, licensed under:

The GNU Lesser General Public License, Version 2.1, February 1999