Merge pull request #3740 from talmakion/feature/T6430-vrf-direct

pbr: T6430: Allow forwarding into VRFs by name as well as route table IDs

interface-definitions/include/policy/route-common.xml.i

@@ -128,6 +128,24 @@
         </completionHelp>
       </properties>
     </leafNode>
+    <leafNode name="vrf">
+      <properties>
+        <help>VRF to forward packet with</help>
+        <valueHelp>
+          <format>txt</format>
+          <description>VRF instance name</description>
+        </valueHelp>
+        <valueHelp>
+          <format>default</format>
+          <description>Forward into default global VRF</description>
+        </valueHelp>
+        <completionHelp>
+          <list>default</list>
+          <path>vrf name</path>
+        </completionHelp>
+        #include <include/constraint/vrf.xml.i>
+      </properties>
+    </leafNode>
     <leafNode name="tcp-mss">
       <properties>
         <help>TCP Maximum Segment Size</help>

python/vyos/defaults.py

@@ -50,3 +50,13 @@
 component_version_json = os.path.join(directories['data'], 'component-versions.json')
 
 config_default = os.path.join(directories['data'], 'config.boot.default')
+
+rt_symbolic_names = {
+  # Standard routing tables for Linux & reserved IDs for VyOS
+  'default': 253, # Confusingly, a final fallthru, not the default. 
+  'main': 254,    # The actual global table used by iproute2 unless told otherwise. 
+  'local': 255,   # Special kernel loopback table.
+}
+
+rt_global_vrf = rt_symbolic_names['main']
+rt_global_table = rt_symbolic_names['main']

python/vyos/firewall.py

@@ -30,6 +30,9 @@
 from vyos.utils.dict import dict_search_recursive
 from vyos.utils.process import cmd
 from vyos.utils.process import run
+from vyos.utils.network import get_vrf_tableid
+from vyos.defaults import rt_global_table
+from vyos.defaults import rt_global_vrf
 
 # Conntrack
 def conntrack_required(conf):
@@ -473,11 +476,20 @@ def parse_rule(rule_conf, hook, fw_name, rule_id, ip_name):
         if 'mark' in rule_conf['set']:
             mark = rule_conf['set']['mark']
             output.append(f'meta mark set {mark}')
+        if 'vrf' in rule_conf['set']:
+            set_table = True
+            vrf_name = rule_conf['set']['vrf']
+            if vrf_name == 'default':
+                table = rt_global_vrf
+            else:
+                # NOTE: VRF->table ID lookup depends on the VRF iface already existing.
+                table = get_vrf_tableid(vrf_name)
         if 'table' in rule_conf['set']:
             set_table = True
             table = rule_conf['set']['table']
             if table == 'main':
-                table = '254'
+                table = rt_global_table
+        if set_table:
             mark = 0x7FFFFFFF - int(table)
             output.append(f'meta mark set {mark}')
         if 'tcp_mss' in rule_conf['set']:

smoketest/scripts/cli/test_policy_route.py

@@ -25,6 +25,8 @@
 conn_mark_set = '111'
 table_mark_offset = 0x7fffffff
 table_id = '101'
+vrf = 'PBRVRF'
+vrf_table_id = '102'
 interface = 'eth0'
 interface_wc = 'ppp*'
 interface_ip = '172.16.10.1/24'
@@ -39,11 +41,14 @@ def setUpClass(cls):
 
         cls.cli_set(cls, ['interfaces', 'ethernet', interface, 'address', interface_ip])
         cls.cli_set(cls, ['protocols', 'static', 'table', table_id, 'route', '0.0.0.0/0', 'interface', interface])
+
+        cls.cli_set(cls, ['vrf', 'name', vrf, 'table', vrf_table_id])
 
     @classmethod
     def tearDownClass(cls):
         cls.cli_delete(cls, ['interfaces', 'ethernet', interface, 'address', interface_ip])
         cls.cli_delete(cls, ['protocols', 'static', 'table', table_id])
+        cls.cli_delete(cls, ['vrf', 'name', vrf])
 
         super(TestPolicyRoute, cls).tearDownClass()
 
@@ -180,6 +185,50 @@ def test_pbr_table(self):
         self.verify_rules(ip_rule_search)
 
 
+    def test_pbr_vrf(self):
+        self.cli_set(['policy', 'route', 'smoketest', 'rule', '1', 'protocol', 'tcp'])
+        self.cli_set(['policy', 'route', 'smoketest', 'rule', '1', 'destination', 'port', '8888'])
+        self.cli_set(['policy', 'route', 'smoketest', 'rule', '1', 'tcp', 'flags', 'syn'])
+        self.cli_set(['policy', 'route', 'smoketest', 'rule', '1', 'tcp', 'flags', 'not', 'ack'])
+        self.cli_set(['policy', 'route', 'smoketest', 'rule', '1', 'set', 'vrf', vrf])
+        self.cli_set(['policy', 'route6', 'smoketest6', 'rule', '1', 'protocol', 'tcp_udp'])
+        self.cli_set(['policy', 'route6', 'smoketest6', 'rule', '1', 'destination', 'port', '8888'])
+        self.cli_set(['policy', 'route6', 'smoketest6', 'rule', '1', 'set', 'vrf', vrf])
+
+        self.cli_set(['policy', 'route', 'smoketest', 'interface', interface])
+        self.cli_set(['policy', 'route6', 'smoketest6', 'interface', interface])
+
+        self.cli_commit()
+
+        mark_hex = "{0:#010x}".format(table_mark_offset - int(vrf_table_id))
+
+        # IPv4
+
+        nftables_search = [
+            [f'iifname "{interface}"', 'jump VYOS_PBR_UD_smoketest'],
+            ['tcp flags syn / syn,ack', 'tcp dport 8888', 'meta mark set ' + mark_hex]
+        ]
+
+        self.verify_nftables(nftables_search, 'ip vyos_mangle')
+
+        # IPv6
+
+        nftables6_search = [
+            [f'iifname "{interface}"', 'jump VYOS_PBR6_UD_smoketest'],
+            ['meta l4proto { tcp, udp }', 'th dport 8888', 'meta mark set ' + mark_hex]
+        ]
+
+        self.verify_nftables(nftables6_search, 'ip6 vyos_mangle')
+
+        # IP rule fwmark -> table
+
+        ip_rule_search = [
+            ['fwmark ' + hex(table_mark_offset - int(vrf_table_id)), 'lookup ' + vrf]
+        ]
+
+        self.verify_rules(ip_rule_search)
+
+
     def test_pbr_matching_criteria(self):
         self.cli_set(['policy', 'route', 'smoketest', 'default-log'])
         self.cli_set(['policy', 'route', 'smoketest', 'rule', '1', 'protocol', 'udp'])

src/conf_mode/policy_route.py

@@ -25,6 +25,9 @@
 from vyos.utils.dict import dict_search_args
 from vyos.utils.process import cmd
 from vyos.utils.process import run
+from vyos.utils.network import get_vrf_tableid
+from vyos.defaults import rt_global_table
+from vyos.defaults import rt_global_vrf
 from vyos import ConfigError
 from vyos import airbag
 airbag.enable()
@@ -83,6 +86,9 @@ def verify_rule(policy, name, rule_conf, ipv6, rule_id):
             if not tcp_flags or 'syn' not in tcp_flags:
                 raise ConfigError(f'{name} rule {rule_id}: TCP SYN flag must be set to modify TCP-MSS')
 
+        if 'vrf' in rule_conf['set'] and 'table' in rule_conf['set']:
+            raise ConfigError(f'{name} rule {rule_id}: Cannot set both forwarding route table and VRF')
+
     tcp_flags = dict_search_args(rule_conf, 'tcp', 'flags')
     if tcp_flags:
         if dict_search_args(rule_conf, 'protocol') != 'tcp':
@@ -152,15 +158,26 @@ def apply_table_marks(policy):
             for name, pol_conf in policy[route].items():
                 if 'rule' in pol_conf:
                     for rule_id, rule_conf in pol_conf['rule'].items():
+                        vrf_table_id = None
                         set_table = dict_search_args(rule_conf, 'set', 'table')
-                        if set_table:
+                        set_vrf = dict_search_args(rule_conf, 'set', 'vrf')
+                        if set_vrf:
+                            if set_vrf == 'default':
+                                vrf_table_id = rt_global_vrf
+                            else:
+                                vrf_table_id = get_vrf_tableid(set_vrf)
+                        elif set_table:
                             if set_table == 'main':
-                                set_table = '254'
-                            if set_table in tables:
+                                vrf_table_id = rt_global_table
+                            else:
+                                vrf_table_id = set_table
+                        if vrf_table_id is not None:
+                            vrf_table_id = int(vrf_table_id)
+                            if vrf_table_id in tables:
                                 continue
-                            tables.append(set_table)
-                            table_mark = mark_offset - int(set_table)
-                            cmd(f'{cmd_str} rule add pref {set_table} fwmark {table_mark} table {set_table}')
+                            tables.append(vrf_table_id)
+                            table_mark = mark_offset - vrf_table_id
+                            cmd(f'{cmd_str} rule add pref {vrf_table_id} fwmark {table_mark} table {vrf_table_id}')
 
 def cleanup_table_marks():
     for cmd_str in ['ip', 'ip -6']: