# Copyright 2023-2024 VyOS maintainers and contributors <maintainers@vyos.io>
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# Lesser General Public License for more details.
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# T5160: Firewall re-writing

#  cli changes from:
#  set firewall name <name> ...
#  set firewall ipv6-name <name> ...
#  To
#  set firewall ipv4 name <name>
#  set firewall ipv6 name <name>

## Also from 'firewall interface' removed.
## in and out:
    # set firewall interface <iface> [in|out] [name | ipv6-name] <name>
    # To
    # set firewall [ipv4 | ipv6] forward filter rule <5,10,15,...> [inbound-interface | outboubd-interface] interface-name <iface>
    # set firewall [ipv4 | ipv6] forward filter rule <5,10,15,...> action jump
    # set firewall [ipv4 | ipv6] forward filter rule <5,10,15,...> jump-target <name>
## local:
    # set firewall interface <iface> local [name | ipv6-name] <name>
    # To
    # set firewall [ipv4 | ipv6] input filter rule <5,10,15,...> inbound-interface interface-name <iface>
    # set firewall [ipv4 | ipv6] input filter rule <5,10,15,...> action jump
    # set firewall [ipv4 | ipv6] input filter rule <5,10,15,...> jump-target <name>

from vyos.configtree import ConfigTree

base = ['firewall']

def migrate(config: ConfigTree) -> None:
    if not config.exists(base):
        # Nothing to do
        return

    ### Migration of state policies
    if config.exists(base + ['state-policy']):
        for state in config.list_nodes(base + ['state-policy']):
            action = config.return_value(base + ['state-policy', state, 'action'])
            config.set(base + ['global-options', 'state-policy', state, 'action'], value=action)
            if config.exists(base + ['state-policy', state, 'log']):
                config.set(base + ['global-options', 'state-policy', state, 'log'], value='enable')
        config.delete(base + ['state-policy'])

    ## migration of global options:
    for option in ['all-ping', 'broadcast-ping', 'config-trap', 'ip-src-route', 'ipv6-receive-redirects', 'ipv6-src-route', 'log-martians',
                    'receive-redirects', 'resolver-cache', 'resolver-internal', 'send-redirects', 'source-validation', 'syn-cookies', 'twa-hazards-protection']:
        if config.exists(base + [option]):
            if option != 'config-trap':
                val = config.return_value(base + [option])
                config.set(base + ['global-options', option], value=val)
            config.delete(base + [option])

    ### Migration of firewall name and ipv6-name
    ### Also migrate legacy 'accept' behaviour
    if config.exists(base + ['name']):
        config.set(['firewall', 'ipv4', 'name'])
        config.set_tag(['firewall', 'ipv4', 'name'])

        for ipv4name in config.list_nodes(base + ['name']):
            config.copy(base + ['name', ipv4name], base + ['ipv4', 'name', ipv4name])

            if config.exists(base + ['ipv4', 'name', ipv4name, 'default-action']):
                action = config.return_value(base + ['ipv4', 'name', ipv4name, 'default-action'])

                if action == 'accept':
                    config.set(base + ['ipv4', 'name', ipv4name, 'default-action'], value='return')

            if config.exists(base + ['ipv4', 'name', ipv4name, 'rule']):
                for rule_id in config.list_nodes(base + ['ipv4', 'name', ipv4name, 'rule']):
                    action = config.return_value(base + ['ipv4', 'name', ipv4name, 'rule', rule_id, 'action'])

                    if action == 'accept':
                        config.set(base + ['ipv4', 'name', ipv4name, 'rule', rule_id, 'action'], value='return')

        config.delete(base + ['name'])

    if config.exists(base + ['ipv6-name']):
        config.set(['firewall', 'ipv6', 'name'])
        config.set_tag(['firewall', 'ipv6', 'name'])

        for ipv6name in config.list_nodes(base + ['ipv6-name']):
            config.copy(base + ['ipv6-name', ipv6name], base + ['ipv6', 'name', ipv6name])

            if config.exists(base + ['ipv6', 'name', ipv6name, 'default-action']):
                action = config.return_value(base + ['ipv6', 'name', ipv6name, 'default-action'])

                if action == 'accept':
                    config.set(base + ['ipv6', 'name', ipv6name, 'default-action'], value='return')

            if config.exists(base + ['ipv6', 'name', ipv6name, 'rule']):
                for rule_id in config.list_nodes(base + ['ipv6', 'name', ipv6name, 'rule']):
                    action = config.return_value(base + ['ipv6', 'name', ipv6name, 'rule', rule_id, 'action'])

                    if action == 'accept':
                        config.set(base + ['ipv6', 'name', ipv6name, 'rule', rule_id, 'action'], value='return')

        config.delete(base + ['ipv6-name'])

    ### Migration of firewall interface
    if config.exists(base + ['interface']):
        fwd_ipv4_rule = 5
        inp_ipv4_rule = 5
        fwd_ipv6_rule = 5
        inp_ipv6_rule = 5
        for direction in ['in', 'out', 'local']:
            for iface in config.list_nodes(base + ['interface']):
                if config.exists(base + ['interface', iface, direction]):
                    if config.exists(base + ['interface', iface, direction, 'name']):
                        target = config.return_value(base + ['interface', iface, direction, 'name'])
                        if direction == 'in':
                            # Add default-action== accept for compatibility reasons:
                            config.set(base + ['ipv4', 'forward', 'filter', 'default-action'], value='accept')
                            new_base = base + ['ipv4', 'forward', 'filter', 'rule']
                            config.set(new_base)
                            config.set_tag(new_base)
                            config.set(new_base + [fwd_ipv4_rule, 'inbound-interface', 'interface-name'], value=iface)
                            config.set(new_base + [fwd_ipv4_rule, 'action'], value='jump')
                            config.set(new_base + [fwd_ipv4_rule, 'jump-target'], value=target)
                            fwd_ipv4_rule = fwd_ipv4_rule + 5
                        elif direction == 'out':
                            # Add default-action== accept for compatibility reasons:
                            config.set(base + ['ipv4', 'forward', 'filter', 'default-action'], value='accept')
                            new_base = base + ['ipv4', 'forward', 'filter', 'rule']
                            config.set(new_base)
                            config.set_tag(new_base)
                            config.set(new_base + [fwd_ipv4_rule, 'outbound-interface', 'interface-name'], value=iface)
                            config.set(new_base + [fwd_ipv4_rule, 'action'], value='jump')
                            config.set(new_base + [fwd_ipv4_rule, 'jump-target'], value=target)
                            fwd_ipv4_rule = fwd_ipv4_rule + 5
                        else:
                            # Add default-action== accept for compatibility reasons:
                            config.set(base + ['ipv4', 'input', 'filter', 'default-action'], value='accept')
                            new_base = base + ['ipv4', 'input', 'filter', 'rule']
                            config.set(new_base)
                            config.set_tag(new_base)
                            config.set(new_base + [inp_ipv4_rule, 'inbound-interface', 'interface-name'], value=iface)
                            config.set(new_base + [inp_ipv4_rule, 'action'], value='jump')
                            config.set(new_base + [inp_ipv4_rule, 'jump-target'], value=target)
                            inp_ipv4_rule = inp_ipv4_rule + 5

                    if config.exists(base + ['interface', iface, direction, 'ipv6-name']):
                        target = config.return_value(base + ['interface', iface, direction, 'ipv6-name'])
                        if direction == 'in':
                            # Add default-action== accept for compatibility reasons:
                            config.set(base + ['ipv6', 'forward', 'filter', 'default-action'], value='accept')
                            new_base = base + ['ipv6', 'forward', 'filter', 'rule']
                            config.set(new_base)
                            config.set_tag(new_base)
                            config.set(new_base + [fwd_ipv6_rule, 'inbound-interface', 'interface-name'], value=iface)
                            config.set(new_base + [fwd_ipv6_rule, 'action'], value='jump')
                            config.set(new_base + [fwd_ipv6_rule, 'jump-target'], value=target)
                            fwd_ipv6_rule = fwd_ipv6_rule + 5
                        elif direction == 'out':
                            # Add default-action== accept for compatibility reasons:
                            config.set(base + ['ipv6', 'forward', 'filter', 'default-action'], value='accept')
                            new_base = base + ['ipv6', 'forward', 'filter', 'rule']
                            config.set(new_base)
                            config.set_tag(new_base)
                            config.set(new_base + [fwd_ipv6_rule, 'outbound-interface', 'interface-name'], value=iface)
                            config.set(new_base + [fwd_ipv6_rule, 'action'], value='jump')
                            config.set(new_base + [fwd_ipv6_rule, 'jump-target'], value=target)
                            fwd_ipv6_rule = fwd_ipv6_rule + 5
                        else:
                            new_base = base + ['ipv6', 'input', 'filter', 'rule']
                            # Add default-action== accept for compatibility reasons:
                            config.set(base + ['ipv6', 'input', 'filter', 'default-action'], value='accept')
                            config.set(new_base)
                            config.set_tag(new_base)
                            config.set(new_base + [inp_ipv6_rule, 'inbound-interface', 'interface-name'], value=iface)
                            config.set(new_base + [inp_ipv6_rule, 'action'], value='jump')
                            config.set(new_base + [inp_ipv6_rule, 'jump-target'], value=target)
                            inp_ipv6_rule = inp_ipv6_rule + 5

        config.delete(base + ['interface'])