pic/tests/test_firewall_manager.py

#!/usr/bin/env python3
"""
Tests for firewall_manager — per-peer iptables rule generation and DNS ACL logic.
All docker exec calls are mocked so tests run without a live Docker environment.
"""

import sys
import os
import tempfile
import shutil
import unittest
from unittest.mock import patch, call, MagicMock
from pathlib import Path

api_dir = Path(__file__).parent.parent / 'api'
sys.path.insert(0, str(api_dir))

import firewall_manager


def _make_peer(ip, internet=True, services=None, peers=True):
    if services is None:
        services = list(firewall_manager.SERVICE_IPS.keys())
    return {'ip': ip, 'internet_access': internet, 'service_access': services, 'peer_access': peers}


# ---------------------------------------------------------------------------
# _peer_comment
# ---------------------------------------------------------------------------

class TestPeerComment(unittest.TestCase):
    def test_dots_replaced_with_dashes(self):
        # Comment format now includes /32 suffix to prevent substring matches
        # (e.g. pic-peer-10-0-0-1/32 is not a prefix of pic-peer-10-0-0-10/32)
        self.assertEqual(firewall_manager._peer_comment('10.0.0.2'), 'pic-peer-10-0-0-2/32')

    def test_different_ip(self):
        self.assertEqual(firewall_manager._peer_comment('192.168.1.100'), 'pic-peer-192-168-1-100/32')


# ---------------------------------------------------------------------------
# _build_acl_block
# ---------------------------------------------------------------------------

class TestBuildAclBlock(unittest.TestCase):
    def test_empty_returns_empty_string(self):
        self.assertEqual(firewall_manager._build_acl_block({}), '')

    def test_no_blocked_peers_returns_empty(self):
        blocked = {s: [] for s in firewall_manager.SERVICE_IPS}
        self.assertEqual(firewall_manager._build_acl_block(blocked), '')

    def test_blocked_peer_appears_in_acl(self):
        blocked = {'calendar': ['10.0.0.5'], 'files': [], 'mail': [], 'webdav': []}
        result = firewall_manager._build_acl_block(blocked)
        self.assertIn('acl calendar.cell.', result)
        self.assertIn('block net 10.0.0.5/32', result)
        self.assertIn('allow net 0.0.0.0/0', result)

    def test_unknown_service_skipped(self):
        blocked = {'nonexistent': ['10.0.0.2']}
        result = firewall_manager._build_acl_block(blocked)
        self.assertEqual(result, '')

    def test_multiple_peers_blocked_from_same_service(self):
        blocked = {'mail': ['10.0.0.2', '10.0.0.3'], 'calendar': [], 'files': [], 'webdav': []}
        result = firewall_manager._build_acl_block(blocked)
        self.assertEqual(result.count('block net'), 2)
        self.assertIn('10.0.0.2/32', result)
        self.assertIn('10.0.0.3/32', result)


# ---------------------------------------------------------------------------
# generate_corefile
# ---------------------------------------------------------------------------

class TestGenerateCorefile(unittest.TestCase):
    def setUp(self):
        self.tmp = tempfile.mkdtemp()
        self.path = os.path.join(self.tmp, 'Corefile')

    def tearDown(self):
        shutil.rmtree(self.tmp)

    def test_creates_corefile(self):
        firewall_manager.generate_corefile([], self.path)
        self.assertTrue(os.path.exists(self.path))

    def test_contains_forward_and_cache(self):
        firewall_manager.generate_corefile([], self.path)
        content = open(self.path).read()
        self.assertIn('forward . 8.8.8.8', content)
        self.assertIn('cache', content)
        self.assertIn('cell {', content)

    def test_no_blocked_services_no_acl_block(self):
        peers = [_make_peer('10.0.0.2', internet=True,
                             services=list(firewall_manager.SERVICE_IPS.keys()))]
        firewall_manager.generate_corefile(peers, self.path)
        content = open(self.path).read()
        self.assertNotIn('block net', content)

    def test_blocked_service_generates_acl(self):
        peers = [_make_peer('10.0.0.3', internet=False, services=['calendar'])]
        firewall_manager.generate_corefile(peers, self.path)
        content = open(self.path).read()
        # files/mail/webdav are blocked for this peer
        self.assertIn('block net 10.0.0.3/32', content)

    def test_peer_with_all_services_allowed_no_acl(self):
        peers = [_make_peer('10.0.0.2', services=list(firewall_manager.SERVICE_IPS.keys()))]
        firewall_manager.generate_corefile(peers, self.path)
        self.assertNotIn('block net', open(self.path).read())

    def test_returns_false_on_write_error(self):
        result = firewall_manager.generate_corefile([], '/nonexistent/path/Corefile')
        self.assertFalse(result)


# ---------------------------------------------------------------------------
# generate_corefile with cell_links
# ---------------------------------------------------------------------------

class TestGenerateCorefileWithCellLinks(unittest.TestCase):
    def setUp(self):
        self.tmp = tempfile.mkdtemp()
        self.path = os.path.join(self.tmp, 'Corefile')

    def tearDown(self):
        shutil.rmtree(self.tmp)

    def _content(self):
        return open(self.path).read()

    def test_cell_links_none_produces_no_forwarding_stanzas(self):
        """Default (None) produces no extra forwarding blocks beyond the primary zone."""
        firewall_manager.generate_corefile([], self.path, cell_links=None)
        content = self._content()
        # The only 'forward' line should be the default internet forwarder
        forward_lines = [l for l in content.splitlines() if 'forward' in l]
        self.assertEqual(len(forward_lines), 1)
        self.assertIn('8.8.8.8', forward_lines[0])

    def test_cell_links_empty_list_produces_no_extra_stanzas(self):
        """An empty cell_links list produces no extra forwarding blocks."""
        firewall_manager.generate_corefile([], self.path, cell_links=[])
        content = self._content()
        forward_lines = [l for l in content.splitlines() if 'forward' in l]
        self.assertEqual(len(forward_lines), 1)
        self.assertIn('8.8.8.8', forward_lines[0])

    def test_single_cell_link_produces_forwarding_block(self):
        """One cell link produces one forwarding stanza with correct domain and dns_ip."""
        cell_links = [{'domain': 'remote.cell', 'dns_ip': '10.1.0.1'}]
        firewall_manager.generate_corefile([], self.path, cell_links=cell_links)
        content = self._content()
        self.assertIn('remote.cell {', content)
        self.assertIn('forward . 10.1.0.1', content)
        self.assertIn('cache', content)

    def test_multiple_cell_links_produce_multiple_forwarding_blocks(self):
        """Multiple cell links produce one stanza each."""
        cell_links = [
            {'domain': 'alpha.cell', 'dns_ip': '10.1.0.1'},
            {'domain': 'beta.cell',  'dns_ip': '10.2.0.1'},
        ]
        firewall_manager.generate_corefile([], self.path, cell_links=cell_links)
        content = self._content()
        self.assertIn('alpha.cell {', content)
        self.assertIn('forward . 10.1.0.1', content)
        self.assertIn('beta.cell {', content)
        self.assertIn('forward . 10.2.0.1', content)

    def test_cell_links_do_not_overwrite_peer_acls(self):
        """Cell link stanzas are appended; peer ACLs in the primary zone survive."""
        peers = [_make_peer('10.0.0.3', services=['calendar'])]
        cell_links = [{'domain': 'other.cell', 'dns_ip': '10.99.0.1'}]
        firewall_manager.generate_corefile(peers, self.path, cell_links=cell_links)
        content = self._content()
        self.assertIn('block net 10.0.0.3/32', content)
        self.assertIn('other.cell {', content)
        self.assertIn('forward . 10.99.0.1', content)

    def test_link_with_missing_domain_is_skipped(self):
        """A cell_link entry with no domain key is silently skipped."""
        cell_links = [{'dns_ip': '10.1.0.1'}]  # no 'domain'
        firewall_manager.generate_corefile([], self.path, cell_links=cell_links)
        content = self._content()
        # Only the default internet forwarder
        forward_lines = [l for l in content.splitlines() if 'forward' in l]
        self.assertEqual(len(forward_lines), 1)

    def test_link_with_missing_dns_ip_is_skipped(self):
        """A cell_link entry with no dns_ip key is silently skipped."""
        cell_links = [{'domain': 'nope.cell'}]  # no 'dns_ip'
        firewall_manager.generate_corefile([], self.path, cell_links=cell_links)
        content = self._content()
        self.assertNotIn('nope.cell', content)


# ---------------------------------------------------------------------------
# apply_peer_rules — iptables call verification
# ---------------------------------------------------------------------------

class TestApplyPeerRules(unittest.TestCase):
    """Verify correct iptables calls for full-internet vs split-tunnel peers."""

    def _run_apply(self, peer_ip, settings):
        calls_made = []

        def fake_wg_exec(args):
            calls_made.append(args)
            m = MagicMock()
            m.returncode = 0
            m.stdout = ''
            return m

        with patch.object(firewall_manager, '_wg_exec', side_effect=fake_wg_exec):
            firewall_manager.apply_peer_rules(peer_ip, settings)

        return calls_made

    def test_full_internet_peer_gets_accept_rule(self):
        calls = self._run_apply('10.0.0.2', {'internet_access': True,
                                              'service_access': list(firewall_manager.SERVICE_IPS.keys()),
                                              'peer_access': True})
        iptables_calls = [c for c in calls if 'iptables' in c]
        targets = [c[c.index('-j') + 1] for c in iptables_calls if '-j' in c]
        # Full-internet peer: only ACCEPT rules (no DROP except iptables-restore clears)
        self.assertNotIn('DROP', targets)
        self.assertIn('ACCEPT', targets)

    def test_no_internet_peer_gets_drop_rule(self):
        calls = self._run_apply('10.0.0.3', {'internet_access': False,
                                              'service_access': list(firewall_manager.SERVICE_IPS.keys()),
                                              'peer_access': True})
        iptables_calls = [c for c in calls if 'iptables' in c]
        targets = [c[c.index('-j') + 1] for c in iptables_calls if '-j' in c]
        self.assertIn('DROP', targets)
        self.assertIn('ACCEPT', targets)

    def test_service_access_restriction_generates_drop(self):
        calls = self._run_apply('10.0.0.4', {'internet_access': False,
                                              'service_access': ['calendar'],
                                              'peer_access': True})
        iptables_calls = [c for c in calls if 'iptables' in c]
        # files/mail/webdav should be DROPped, calendar ACCEPTed
        targets_with_ips = [
            (c[c.index('-d') + 1], c[c.index('-j') + 1])
            for c in iptables_calls
            if '-d' in c and '-j' in c
        ]
        svc_rules = {ip: t for ip, t in targets_with_ips
                     if ip in firewall_manager.SERVICE_IPS.values()}
        calendar_ip = firewall_manager.SERVICE_IPS['calendar']
        files_ip = firewall_manager.SERVICE_IPS['files']
        self.assertEqual(svc_rules.get(calendar_ip), 'ACCEPT')
        self.assertEqual(svc_rules.get(files_ip), 'DROP')

    def test_all_rules_tagged_with_peer_comment(self):
        calls = self._run_apply('10.0.0.2', {'internet_access': True,
                                              'service_access': list(firewall_manager.SERVICE_IPS.keys()),
                                              'peer_access': True})
        iptables_calls = [c for c in calls if 'iptables' in c]
        comment = firewall_manager._peer_comment('10.0.0.2')
        for c in iptables_calls:
            if '-I' in c:  # only insertion rules need the comment
                self.assertIn(comment, c, f"Rule missing comment tag: {c}")

    def test_peer_with_no_peer_access_gets_drop_for_vpn_subnet(self):
        calls = self._run_apply('10.0.0.5', {'internet_access': True,
                                              'service_access': list(firewall_manager.SERVICE_IPS.keys()),
                                              'peer_access': False})
        iptables_calls = [c for c in calls if 'iptables' in c]
        vpn_rules = [c for c in iptables_calls if '-d' in c and '10.0.0.0/24' in c]
        self.assertTrue(vpn_rules, "Expected a rule for 10.0.0.0/24")
        for c in vpn_rules:
            self.assertIn('DROP', c)


# ---------------------------------------------------------------------------
# apply_all_peer_rules
# ---------------------------------------------------------------------------

class TestApplyAllPeerRules(unittest.TestCase):
    def test_calls_apply_per_peer(self):
        peers = [_make_peer('10.0.0.2'), _make_peer('10.0.0.3', internet=False)]
        with patch.object(firewall_manager, 'ensure_caddy_virtual_ips', return_value=True), \
             patch.object(firewall_manager, 'apply_peer_rules', return_value=True) as mock_apply:
            firewall_manager.apply_all_peer_rules(peers)
        self.assertEqual(mock_apply.call_count, 2)
        called_ips = {c.args[0] for c in mock_apply.call_args_list}
        self.assertEqual(called_ips, {'10.0.0.2', '10.0.0.3'})

    def test_peer_without_ip_is_skipped(self):
        peers = [{'internet_access': True}, _make_peer('10.0.0.2')]
        with patch.object(firewall_manager, 'ensure_caddy_virtual_ips', return_value=True), \
             patch.object(firewall_manager, 'apply_peer_rules', return_value=True) as mock_apply:
            firewall_manager.apply_all_peer_rules(peers)
        self.assertEqual(mock_apply.call_count, 1)


# ---------------------------------------------------------------------------
# clear_peer_rules
# ---------------------------------------------------------------------------

class TestClearPeerRules(unittest.TestCase):
    def test_removes_only_matching_comment_lines(self):
        save_output = (
            '*filter\n'
            ':INPUT ACCEPT [0:0]\n'
            ':FORWARD ACCEPT [0:0]\n'
            '-A FORWARD -s 10.0.0.2 -m comment --comment "pic-peer-10-0-0-2/32" -j ACCEPT\n'
            '-A FORWARD -s 10.0.0.3 -m comment --comment "pic-peer-10-0-0-3/32" -j DROP\n'
            'COMMIT\n'
        )
        restored = []

        def fake_wg_exec(args):
            m = MagicMock()
            m.returncode = 0
            if args == ['iptables-save']:
                m.stdout = save_output
            return m

        def fake_restore(cmd, input, **kwargs):
            restored.append(input)
            m = MagicMock()
            m.returncode = 0
            return m

        with patch.object(firewall_manager, '_wg_exec', side_effect=fake_wg_exec), \
             patch('subprocess.run', side_effect=fake_restore):
            firewall_manager.clear_peer_rules('10.0.0.2')

        self.assertEqual(len(restored), 1)
        restored_content = restored[0]
        self.assertNotIn('pic-peer-10-0-0-2/32', restored_content)
        self.assertIn('pic-peer-10-0-0-3/32', restored_content)

    def test_no_op_when_no_matching_rules(self):
        save_output = '*filter\n:FORWARD ACCEPT [0:0]\nCOMMIT\n'

        def fake_wg_exec(args):
            m = MagicMock()
            m.returncode = 0
            m.stdout = save_output
            return m

        with patch.object(firewall_manager, '_wg_exec', side_effect=fake_wg_exec), \
             patch('subprocess.run') as mock_restore:
            firewall_manager.clear_peer_rules('10.0.0.99')

        mock_restore.assert_not_called()


# ---------------------------------------------------------------------------
# update_service_ips
# ---------------------------------------------------------------------------

class TestUpdateServiceIps(unittest.TestCase):
    def tearDown(self):
        # Restore default SERVICE_IPS after each test
        firewall_manager.update_service_ips('172.20.0.0/16')

    def test_default_ips_are_172_20(self):
        self.assertEqual(firewall_manager.SERVICE_IPS['calendar'], '172.20.0.21')
        self.assertEqual(firewall_manager.SERVICE_IPS['webdav'],   '172.20.0.24')

    def test_update_changes_all_virtual_ips(self):
        firewall_manager.update_service_ips('10.0.0.0/24')
        self.assertEqual(firewall_manager.SERVICE_IPS['calendar'], '10.0.0.21')
        self.assertEqual(firewall_manager.SERVICE_IPS['files'],    '10.0.0.22')
        self.assertEqual(firewall_manager.SERVICE_IPS['mail'],     '10.0.0.23')
        self.assertEqual(firewall_manager.SERVICE_IPS['webdav'],   '10.0.0.24')

    def test_update_replaces_not_extends(self):
        firewall_manager.update_service_ips('10.0.0.0/24')
        # Should only have the four virtual-IP keys
        self.assertEqual(set(firewall_manager.SERVICE_IPS.keys()),
                         {'calendar', 'files', 'mail', 'webdav'})

    def test_apply_peer_rules_uses_updated_ips(self):
        firewall_manager.update_service_ips('10.0.0.0/24')
        called_with = []

        def fake_wg_exec(args):
            called_with.append(args)
            m = MagicMock()
            m.returncode = 1  # simulate rule-doesn't-exist → _ensure_rule inserts
            return m

        with patch.object(firewall_manager, '_wg_exec', side_effect=fake_wg_exec), \
             patch.object(firewall_manager, 'clear_peer_rules'):
            firewall_manager.apply_peer_rules('10.0.0.5', {
                'internet_access': True,
                'service_access': ['calendar'],
                'peer_access': True,
            })

        iptables_calls = [c for c in called_with if c and c[0] == 'iptables']
        dest_ips = [c[c.index('-d') + 1] for c in iptables_calls if '-d' in c]
        # calendar vIP should now be 10.0.0.21
        self.assertIn('10.0.0.21', dest_ips)
        # old IP must not appear
        self.assertNotIn('172.20.0.21', dest_ips)


if __name__ == '__main__':
    unittest.main()