Merge pull request #29 from natali-rs1985/T7181-stati+dynamic

T7181: VPP Static and dynamic NAT

1 files changed, 458 insertions, 0 deletions

diff --git a/src/conf_mode/vpp_nat.py b/src/conf_mode/vpp_nat.py
new file mode 100644
index 000000000..d38599388
--- /dev/null
+++ b/src/conf_mode/vpp_nat.py
@@ -0,0 +1,458 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2025 VyOS Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+import ipaddress
+
+from vyos import ConfigError
+
+from vyos.configdiff import Diff
+from vyos.configdict import node_changed
+from vyos.config import Config
+from vyos.utils.network import get_interface_address
+
+from vyos.vpp.utils import cli_ifaces_list
+from vyos.vpp.nat.nat44 import Nat44
+
+
+protocol_map = {
+    'all': 0,
+    'icmp': 1,
+    'tcp': 6,
+    'udp': 17,
+}
+
+
+def get_config(config=None) -> dict:
+    if config:
+        conf = config
+    else:
+        conf = Config()
+
+    base = ['vpp', 'nat44']
+
+    # Get config_dict with default values
+    config = conf.get_config_dict(
+        base,
+        key_mangling=('-', '_'),
+        get_first_key=True,
+        no_tag_node_value_mangle=True,
+        with_defaults=True,
+        with_recursive_defaults=True,
+    )
+
+    # Get effective config as we need full dictionary for deletion
+    effective_config = conf.get_config_dict(
+        base,
+        key_mangling=('-', '_'),
+        effective=True,
+        get_first_key=True,
+        no_tag_node_value_mangle=True,
+    )
+
+    if not config:
+        config['remove'] = True
+        return config
+
+    config_changed = node_changed(
+        conf,
+        base,
+        key_mangling=('-', '_'),
+        recursive=True,
+        expand_nodes=Diff.DELETE | Diff.ADD,
+    )
+
+    changed_static_rules = node_changed(
+        conf,
+        base + ['static', 'rule'],
+        key_mangling=('-', '_'),
+        recursive=True,
+        expand_nodes=Diff.DELETE | Diff.ADD,
+    )
+
+    changed_exclude_rules = node_changed(
+        conf,
+        base + ['exclude', 'rule'],
+        key_mangling=('-', '_'),
+        recursive=True,
+        expand_nodes=Diff.DELETE | Diff.ADD,
+    )
+
+    if not config_changed:
+        changed_static_rules = list(config.get('static', {}).get('rule', {}).keys())
+        changed_exclude_rules = list(config.get('exclude', {}).get('rule', {}).keys())
+
+    config.update(
+        {
+            'changed_static_rules': changed_static_rules,
+            'changed_exclude_rules': changed_exclude_rules,
+            'vpp_ifaces': cli_ifaces_list(conf),
+        }
+    )
+
+    if effective_config:
+        config.update({'effective': effective_config})
+
+    return config
+
+
+def convert_range_to_list_ips(address_range) -> list:
+    """Converts IP range to a list of IPs .
+
+    Example:
+    % ip = IPOperations('192.0.0.1-192.0.2.5')
+    % ip.convert_prefix_to_list_ips()
+    ['192.0.2.1', '192.0.2.2', '192.0.2.3', '192.0.2.4', '192.0.2.5']
+    """
+    if '-' in address_range:
+        start_ip, end_ip = address_range.split('-')
+        start_ip = ipaddress.ip_address(start_ip)
+        end_ip = ipaddress.ip_address(end_ip)
+        return [
+            str(ipaddress.ip_address(ip))
+            for ip in range(int(start_ip), int(end_ip) + 1)
+        ]
+    else:
+        return [address_range]
+
+
+def verify(config):
+    if 'remove' in config:
+        return None
+
+    if 'interface' not in config:
+        raise ConfigError('Interfaces must be configured for NAT44')
+
+    required_keys = {'inside', 'outside'}
+    missing_keys = required_keys - set(config['interface'].keys())
+    if missing_keys:
+        raise ConfigError(
+            f'Both inside and outside interfaces must be configured. Please add: {", ".join(missing_keys)}'
+        )
+
+    for interface in config['interface']['inside']:
+        if interface not in config['vpp_ifaces']:
+            raise ConfigError(
+                f'{interface} must be a VPP interface for inside NAT interface'
+            )
+    for interface in config['interface']['outside']:
+        if interface not in config['vpp_ifaces']:
+            raise ConfigError(
+                f'{interface} must be a VPP interface for outside NAT interface'
+            )
+
+    if not config.get('address_pool', {}).get('translation') and not config.get(
+        'static', {}
+    ).get('rule'):
+        raise ConfigError('"address-pool translation" or "static rule" is required')
+
+    addresses_translation = []
+    addresses_twice_nat = []
+    if 'address_pool' in config:
+        address_pool = config.get('address_pool')
+        if 'translation' in address_pool:
+            if not address_pool['translation'].get('address') and not address_pool[
+                'translation'
+            ].get('interface'):
+                raise ConfigError(
+                    '"address-pool translation" requires address or interface'
+                )
+
+            for address_range in address_pool['translation'].get('address', []):
+                addresses = convert_range_to_list_ips(address_range)
+                for address in addresses:
+                    if address in addresses_translation:
+                        raise ConfigError(
+                            f'Address {address} is already in use in "address-pool translation address"'
+                        )
+                    addresses_translation.append(address)
+
+            for interface in address_pool['translation'].get('interface', []):
+                if interface not in config['vpp_ifaces']:
+                    raise ConfigError(
+                        f'{interface} must be a VPP interface for "address-pool translation interface"'
+                    )
+                iface_address = get_interface_address(interface).get('addr_info', [])[0].get('local')
+                addresses_translation.append(iface_address)
+
+        if 'twice_nat' in address_pool:
+            if not address_pool['twice_nat'].get('address') and not address_pool[
+                'twice_nat'
+            ].get('interface'):
+                raise ConfigError(
+                    '"address-pool twice-nat" requires address or interface'
+                )
+
+            for address_range in address_pool['twice_nat'].get('address', []):
+                addresses = convert_range_to_list_ips(address_range)
+                for address in addresses:
+                    if address in addresses_twice_nat:
+                        raise ConfigError(
+                            f'Address {address} is already in use in "address-pool twice-nat address"'
+                        )
+                    addresses_twice_nat.append(address)
+
+            for interface in address_pool['twice_nat'].get('interface', []):
+                if interface not in config['vpp_ifaces']:
+                    raise ConfigError(
+                        f'{interface} must be a VPP interface for "address-pool twice-nat interface"'
+                    )
+                iface_address = get_interface_address(interface).get('addr_info', [])[0].get('local')
+                addresses_twice_nat.append(iface_address)
+
+    if 'static' in config:
+        addresses_with_ports = set()
+        addresses_without_ports = set()
+        local_addresses = set()
+
+        for rule, rule_config in config['static']['rule'].items():
+            error_msg = f'Configuration error in static rule {rule}:'
+
+            if not rule_config.get('local', {}).get('address'):
+                raise ConfigError(f'{error_msg} local settings require address')
+
+            if not rule_config.get('external', {}).get('address'):
+                raise ConfigError(f'{error_msg} external settings require address')
+
+            has_local_port = 'port' in rule_config.get('local', {})
+            has_external_port = 'port' in rule_config.get('external', {})
+
+            if not has_external_port == has_local_port:
+                raise ConfigError(
+                    f'{error_msg} source and destination ports must either '
+                    'both be specified, or neither must be specified'
+                )
+
+            ext_address = rule_config['external']['address']
+            port = rule_config['external'].get('port')
+            local_address = rule_config['local']['address']
+
+            if port:
+                pair = (ext_address, port)
+                if (
+                    pair in addresses_with_ports
+                    or ext_address in addresses_without_ports
+                ):
+                    raise ConfigError(
+                        f'{error_msg} external address/port is already in use!'
+                    )
+                addresses_with_ports.add(pair)
+                if ext_address not in addresses_translation:
+                    raise ConfigError(
+                        f'{error_msg} external address {ext_address} is not in "address-pool translation"'
+                    )
+
+            else:
+                if ext_address in addresses_without_ports or any(
+                    addr == ext_address for addr, _ in addresses_with_ports
+                ):
+                    raise ConfigError(
+                        f'{error_msg} external address is already in use!'
+                    )
+                addresses_without_ports.add(ext_address)
+
+                if local_address in local_addresses:
+                    raise ConfigError(
+                        f'{error_msg} local address {local_address} is already in use'
+                    )
+                local_addresses.add(local_address)
+
+            options = rule_config.get('options', {})
+            if all(key in options for key in ('twice_nat', 'self_twice_nat')):
+                raise ConfigError(
+                    f'{error_msg} cannot set both options "twice-nat" and "self-twice-nat"'
+                )
+            if any(key in options for key in ('twice_nat', 'self_twice_nat')):
+                if not has_local_port or rule_config['protocol'] == 'all':
+                    raise ConfigError(
+                        f'{error_msg} twice-nat/self-twice-nat options require port and protocol to be set'
+                    )
+                if not config.get('address_pool', {}).get('twice_nat'):
+                    raise ConfigError(
+                        f'{error_msg} twice-nat/self-twice-nat options require "address-pool twice-nat" to be set'
+                    )
+            if 'twice_nat_address' in options:
+                if not any(key in options for key in ('twice_nat', 'self_twice_nat')):
+                    raise ConfigError(
+                        f'{error_msg} twice-nat/self-twice-nat option required when twice-nat-address is set'
+                    )
+                tn_address = options['twice_nat_address']
+                if tn_address not in addresses_twice_nat:
+                    raise ConfigError(
+                        f'{error_msg} twice-nat-address {tn_address} is not in "address-pool twice-nat"'
+                    )
+
+    if 'exclude' in config:
+        for rule, rule_config in config['exclude']['rule'].items():
+            keys = {'local_address', 'external_interface'}
+            if not any(key in rule_config for key in keys):
+                raise ConfigError(
+                    f'Local-address or external-interface must be specified for exclude rule {rule}'
+                )
+            if all(key in rule_config for key in keys):
+                raise ConfigError(
+                    f'Cannot set both address and interface for exclude rule {rule}'
+                )
+            if (
+                'external_interface' in rule_config
+                and rule_config.get('external_interface') not in config['vpp_ifaces']
+            ):
+                raise ConfigError(
+                    f'{rule_config["external_interface"]} must be a VPP interface for exclude rule {rule}'
+                )
+
+
+def generate(config):
+    pass
+
+
+def apply(config):
+    n = Nat44()
+
+    if 'remove' in config:
+        n.disable_nat44_ed()
+        return None
+
+    if 'effective' in config:
+        remove_config = config.get('effective')
+        # Delete inside interfaces
+        for interface in remove_config['interface']['inside']:
+            if interface not in config.get('interface', {}).get('inside', []):
+                n.delete_nat44_interface_inside(interface)
+        # Delete outside interfaces
+        for interface in remove_config['interface']['outside']:
+            if interface not in config.get('interface', {}).get('outside', []):
+                n.delete_nat44_interface_outside(interface)
+        # Delete address pool
+        address_pool = config.get('address_pool', {})
+        for address in (
+            remove_config.get('address_pool', {})
+            .get('translation', {})
+            .get('address', [])
+        ):
+            if address not in address_pool.get('translation', {}).get('address', []):
+                n.delete_nat44_address_range(address, twice_nat=False)
+        for interface in (
+            remove_config.get('address_pool', {})
+            .get('translation', {})
+            .get('interface', [])
+        ):
+            if interface not in address_pool.get('translation', {}).get(
+                'interface', []
+            ):
+                n.delete_nat44_interface_address(interface, twice_nat=False)
+        for address in (
+            remove_config.get('address_pool', {})
+            .get('twice_nat', {})
+            .get('address', [])
+        ):
+            if address not in address_pool.get('twice_nat', {}).get('address', []):
+                n.delete_nat44_address_range(address, twice_nat=True)
+        for interface in (
+            remove_config.get('address_pool', {})
+            .get('twice_nat', {})
+            .get('interface', [])
+        ):
+            if interface not in address_pool.get('twice_nat', {}).get('interface', []):
+                n.delete_nat44_interface_address(interface, twice_nat=True)
+        # Delete NAT static mapping rules
+        for rule in config['changed_static_rules']:
+            if rule in remove_config.get('static', {}).get('rule', {}):
+                rule_config = remove_config['static']['rule'][rule]
+                n.delete_nat44_static_mapping(
+                    local_ip=rule_config.get('local').get('address'),
+                    external_ip=rule_config.get('external', {}).get('address', ''),
+                    local_port=int(rule_config.get('local', {}).get('port', 0)),
+                    external_port=int(rule_config.get('external', {}).get('port', 0)),
+                    protocol=protocol_map[rule_config.get('protocol', 'all')],
+                    twice_nat='twice_nat' in rule_config.get('options', {}),
+                    self_twice_nat='self_twice_nat' in rule_config.get('options', {}),
+                    out2in='out_to_in_only' in rule_config.get('options', {}),
+                    pool_ip=rule_config.get('options', {}).get('twice_nat_address'),
+                )
+        # Delete NAT exclude rules
+        for rule in config['changed_exclude_rules']:
+            if rule in remove_config.get('exclude', {}).get('rule', {}):
+                rule_config = remove_config['exclude']['rule'][rule]
+                n.delete_nat44_identity_mapping(
+                    ip_address=rule_config.get('local_address'),
+                    protocol=protocol_map[rule_config.get('protocol', 'all')],
+                    port=int(rule_config.get('local_port', 0)),
+                    interface=rule_config.get('external_interface'),
+                )
+
+    # Add NAT44
+    n.enable_nat44_ed()
+    # Add inside interfaces
+    for interface in config['interface']['inside']:
+        n.add_nat44_interface_inside(interface)
+    # Add outside interfaces
+    for interface in config['interface']['outside']:
+        n.add_nat44_interface_outside(interface)
+    # Add translation pool
+    for address in (
+        config.get('address_pool', {}).get('translation', {}).get('address', [])
+    ):
+        n.add_nat44_address_range(address, twice_nat=False)
+    for interface in (
+        config.get('address_pool', {}).get('translation', {}).get('interface', [])
+    ):
+        n.add_nat44_interface_address(interface, twice_nat=False)
+    for address in (
+        config.get('address_pool', {}).get('twice_nat', {}).get('address', [])
+    ):
+        n.add_nat44_address_range(address, twice_nat=True)
+    for interface in (
+        config.get('address_pool', {}).get('twice_nat', {}).get('interface', [])
+    ):
+        n.add_nat44_interface_address(interface, twice_nat=True)
+    # Add NAT static mapping rules
+    for rule in config['changed_static_rules']:
+        if rule in config.get('static', {}).get('rule', {}):
+            rule_config = config['static']['rule'][rule]
+            n.add_nat44_static_mapping(
+                local_ip=rule_config.get('local').get('address'),
+                external_ip=rule_config.get('external', {}).get('address', ''),
+                local_port=int(rule_config.get('local', {}).get('port', 0)),
+                external_port=int(rule_config.get('external', {}).get('port', 0)),
+                protocol=protocol_map[rule_config.get('protocol', 'all')],
+                twice_nat='twice_nat' in rule_config.get('options', {}),
+                self_twice_nat='self_twice_nat' in rule_config.get('options', {}),
+                out2in='out_to_in_only' in rule_config.get('options', {}),
+                pool_ip=rule_config.get('options', {}).get('twice_nat_address'),
+            )
+    # Add NAT exclude rules
+    for rule in config['changed_exclude_rules']:
+        if rule in config.get('exclude', {}).get('rule', {}):
+            rule_config = config['exclude']['rule'][rule]
+            n.add_nat44_identity_mapping(
+                ip_address=rule_config.get('local_address'),
+                protocol=protocol_map[rule_config.get('protocol', 'all')],
+                port=int(rule_config.get('local_port', 0)),
+                interface=rule_config.get('external_interface'),
+            )
+
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)