feat: Support blackhole, prohibit and unreachable route types

It is useful and common practice to configure the routes with blackhole,
prohibit, and unreachable route types when users have BGP routing
setups.

Notice that this feature is only for nm provider using
`network_connections` variable. Configuring blackhole, prohibit, and
unreachable route types is also supported by using `network_state` since
nmstate version 2.2.20 (the setting name is `route-type`).

Resolves: https://issues.redhat.com/browse/RHEL-19579

Signed-off-by: Wen Liang <liangwen12year@gmail.com>

README.md

@@ -586,13 +586,17 @@ The IP configuration supports the following options:
 
   Static route configuration can be specified via a list of routes given in the
   `route` option. The default value is an empty list. Each route is a dictionary with
-  the following entries: `network`, `prefix`, `gateway`, `metric` and `table`.
+  the following entries: `gateway`, `metric`, `network`, `prefix`, `table` and `type`.
   `network` and `prefix` specify the destination network. `table` supports both the
-  numeric table and named table. In order to specify the named table, the users have
-  to ensure the named table is properly defined in `/etc/iproute2/rt_tables` or
-  `/etc/iproute2/rt_tables.d/*.conf`.
-  Note that Classless inter-domain routing (CIDR) notation or network mask notation
-  are not supported yet.
+  numeric table and named table. In order to specify the named table, the users have to
+  ensure the named table is properly defined in `/etc/iproute2/rt_tables` or
+  `/etc/iproute2/rt_tables.d/*.conf`. The optional `type` key supports the values
+  `blackhole`, `prohibit`, and `unreachable`.
+  See [man 8 ip-route](https://man7.org/linux/man-pages/man8/ip-route.8.html#DESCRIPTION)
+  for their definition. Routes with these types do not support a gateway. If the type
+  is not specified, the route is considered as a unicast route. Note that the classless
+  inter-domain routing(CIDR) notation or the network mask notation are not supported
+  for the `network` key.
 
 - `routing_rule`
 

examples/route_type_support.yml

@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: BSD-3-Clause
+---
+- name: Manage route type routes
+  hosts: all
+  tasks:
+    - name: Configure connection profile and route type routes
+      import_role:
+        name: linux-system-roles.network
+      vars:
+        network_connections:
+          - name: eth0
+            interface_name: eth0
+            state: up
+            type: ethernet
+            autoconnect: true
+            ip:
+              dhcp4: false
+              address:
+                - 198.51.100.3/26
+                - 2001:db8::2/32
+              route:
+                - network: 198.51.100.64
+                  prefix: 26
+                  gateway: 198.51.100.6
+                  metric: 4
+                  table: 30200
+                - network: 198.53.100.18
+                  prefix: 32
+                  metric: 20
+                  type: blackhole
+                  table: 30200
+                - network: 198.53.100.12
+                  prefix: 32
+                  metric: 24
+                  type: unreachable
+                  table: 30200
+                - network: 198.53.100.10
+                  prefix: 32
+                  metric: 30
+                  type: prohibit
+                  table: 30200
+                - network: 2001:db8::4
+                  prefix: 128
+                  metric: 2
+                  type: blackhole
+                  table: 30600
+                - network: 2001:db8::6
+                  prefix: 128
+                  metric: 4
+                  type: prohibit
+                  table: 30600

library/network_connections.py

@@ -1255,6 +1255,10 @@ def connection_create(self, connections, idx, connection_current=None):
                 new_route = NM.IPRoute.new(
                     r["family"], r["network"], r["prefix"], r["gateway"], r["metric"]
                 )
+                if r["type"]:
+                    NM.IPRoute.set_attribute(
+                        new_route, "type", Util.GLib().Variant("s", r["type"])
+                    )
                 if r["table"]:
                     NM.IPRoute.set_attribute(
                         new_route, "table", Util.GLib().Variant.new_uint32(r["table"])
@@ -2193,6 +2197,18 @@ def run_action_up(self, idx):
 ###############################################################################
 
 
+def version_to_tuple(version):
+    """
+    Translates the dot-separated version string to a tuple
+
+    :param version: The dot-separated version string
+    :return: the version tuple
+    """
+    version_list = version.split(".")
+    version_tuple = tuple(map(int, version_list))
+    return version_tuple
+
+
 class Cmd_nm(Cmd):
     def __init__(self, **kwargs):
         Cmd.__init__(self, **kwargs)
@@ -2222,7 +2238,21 @@ def run_prepare(self):
         names = {}
         for idx, connection in enumerate(self.connections):
             self._check_ethtool_setting_support(idx, connection)
-
+            if connection.get("ip", {}):
+                for route in connection["ip"]["route"]:
+                    if route["type"]:
+                        # The special route type prohibit, blackhole and unreachable
+                        # are only supported in NM since version 1.36.0
+                        nm_client_version = self._nm_provider.get_client_version()
+                        if version_to_tuple(nm_client_version) < (1, 36, 0):
+                            self.log_fatal(
+                                idx,
+                                "route type {0} is only supported in NM since 1.36.0 "
+                                "but the NM client version is {1}".format(
+                                    route["type"],
+                                    nm_client_version,
+                                ),
+                            )
             name = connection["name"]
             if not name:
                 if not connection["persistent_state"] == "absent":

module_utils/network_lsr/argument_validator.py

@@ -674,6 +674,11 @@ def __init__(self, name, family=None, required=False):
                 ArgValidatorNum(
                     "metric", default_value=-1, val_min=-1, val_max=UINT32_MAX
                 ),
+                ArgValidatorStr(
+                    "type",
+                    default_value=None,
+                    enum_values=["blackhole", "prohibit", "unreachable"],
+                ),
                 ArgValidatorRouteTable("table"),
             ],
             default_value=None,
@@ -688,13 +693,20 @@ def _validate_post(self, value, name, result):
         result["family"] = family
 
         gateway = result["gateway"]
+        route_type = result["type"]
         if gateway is not None:
             if family != gateway["family"]:
                 raise ValidationError(
                     name,
                     "conflicting address family between network and gateway '%s'"
                     % (gateway["address"]),
                 )
+            if route_type is not None:
+                raise ValidationError(
+                    name,
+                    "a %s route can not have a gateway '%s'"
+                    % (route_type, gateway["address"]),
+                )
             result["gateway"] = gateway["address"]
 
         prefix = result["prefix"]
@@ -2607,6 +2619,14 @@ def _ipv6_is_not_configured(connection):
                         "NetworkManger until NM 1.30",
                     )
 
+        if connection["ip"]["route"]:
+            if mode == self.VALIDATE_ONE_MODE_INITSCRIPTS:
+                for route in connection["ip"]["route"]:
+                    if route["type"] is not None:
+                        raise ValidationError.from_connection(
+                            idx,
+                            "type is not supported by initscripts",
+                        )
         if connection["ip"]["routing_rule"]:
             if mode == self.VALIDATE_ONE_MODE_INITSCRIPTS:
                 raise ValidationError.from_connection(

tests/ensure_provider_tests.py

@@ -95,6 +95,11 @@
     },
     "playbooks/tests_reapply.yml": {},
     "playbooks/tests_route_table.yml": {},
+    "playbooks/tests_route_type.yml": {
+        MINIMUM_VERSION: "'1.36.0'",
+        "comment": "# NetworkManager 1.36.0 added support for special route types: \
+blackhole, prohibit and unreachable",
+    },
     "playbooks/tests_routing_rules.yml": {},
     # team interface is not supported on Fedora
     "playbooks/tests_team.yml": {

tests/playbooks/tests_route_type.yml

@@ -0,0 +1,194 @@
+# SPDX-License-Identifier: BSD-3-Clause
+---
+- name: Play for testing route types
+  hosts: all
+  vars:
+    type: veth
+    interface: ethtest0
+  tasks:
+    - name: "Set type={{ type }} and interface={{ interface }}"  # noqa name
+      set_fact:
+        type: "{{ type }}"
+        interface: "{{ interface }}"
+    - name: Include the task 'show_interfaces.yml'
+      include_tasks: tasks/show_interfaces.yml
+    - name: Include the task 'manage_test_interface.yml'
+      include_tasks: tasks/manage_test_interface.yml
+      vars:
+        state: present
+    - name: Include the task 'assert_device_present.yml'
+      include_tasks: tasks/assert_device_present.yml
+
+    - name: Configure connection profile and specify the route types in
+        static routes
+      import_role:
+        name: linux-system-roles.network
+      vars:
+        network_connections:
+          - name: "{{ interface }}"
+            interface_name: "{{ interface }}"
+            state: up
+            type: ethernet
+            autoconnect: true
+            ip:
+              dhcp4: false
+              address:
+                - 198.51.100.3/26
+                - 2001:db8::2/32
+              route:
+                - network: 198.51.100.64
+                  prefix: 26
+                  gateway: 198.51.100.6
+                  metric: 4
+                  table: 30200
+                - network: 198.53.100.18
+                  prefix: 32
+                  metric: 20
+                  type: blackhole
+                  table: 30200
+                - network: 198.53.100.10
+                  prefix: 32
+                  metric: 30
+                  type: prohibit
+                  table: 30200
+                - network: 198.53.100.12
+                  prefix: 32
+                  metric: 24
+                  type: unreachable
+                  table: 30200
+                - network: 2001:db8::4
+                  prefix: 128
+                  metric: 2
+                  type: blackhole
+                  table: 30600
+                - network: 2001:db8::6
+                  prefix: 128
+                  metric: 4
+                  type: prohibit
+                  table: 30600
+
+    - name: Get the routes from the route table 30200
+      command: ip route show table 30200
+      register: route_table_30200
+      changed_when: false
+
+    - name: Get the routes from the route table 30600
+      command: ip -6 route show table 30600
+      register: route_table_30600
+      changed_when: false
+
+    - name: Assert that the route table 30200 contains the specified route
+      assert:
+        that:
+          - route_table_30200.stdout is search("198.51.100.64/26 via
+            198.51.100.6 dev ethtest0 proto static metric 4")
+          - route_table_30200.stdout is search("blackhole 198.53.100.18
+            proto static scope link metric 20")
+          - route_table_30200.stdout is search("prohibit 198.53.100.10
+            proto static scope link metric 30")
+          - route_table_30200.stdout is search("unreachable 198.53.100.12
+            proto static scope link metric 24")
+        msg: "the route table 30200 does not exist or does not contain the
+          specified route"
+
+    - name: Assert that the route table 30600 contains the specified route
+      assert:
+        that:
+          - route_table_30600.stdout is search("blackhole 2001:db8::4
+            dev lo proto static metric 2 pref medium")
+          - route_table_30600.stdout is search("prohibit 2001:db8::6
+            dev lo proto static metric 4 pref medium")
+        msg: "the route table 30600 does not exist or does not contain the
+          specified route"
+
+    - name: Removing some routes
+      import_role:
+        name: linux-system-roles.network
+      vars:
+        network_connections:
+          - name: "{{ interface }}"
+            interface_name: "{{ interface }}"
+            state: up
+            type: ethernet
+            autoconnect: true
+            ip:
+              dhcp4: false
+              address:
+                - 198.51.100.3/26
+                - 2001:db8::2/32
+              route:
+                - network: 198.51.100.64
+                  prefix: 26
+                  gateway: 198.51.100.6
+                  metric: 4
+                  table: 30200
+                - network: 2001:db8::4
+                  prefix: 128
+                  metric: 2
+                  type: blackhole
+                  table: 30600
+                - network: 2001:db8::6
+                  prefix: 128
+                  metric: 4
+                  type: prohibit
+                  table: 30600
+
+    - name: Get the routes from the route table 30200 after removing routes
+      command: ip route show table 30200
+      register: table_30200
+      changed_when: false
+
+    - name: Get the routes from the route table 30600 after removing routes
+      command: ip -6 route show table 30600
+      register: table_30600
+      changed_when: false
+
+    - name: Assert that the route table 30200 contains the specified unicast
+        route
+      assert:
+        that:
+          - route_table_30200.stdout is search("198.51.100.64/26 via
+            198.51.100.6 dev ethtest0 proto static metric 4")
+        msg: "the route table 30200 does not exist or does not contain the
+          specified unicast route"
+
+    - name: Assert that the route table 30200 does not contain the type routes
+      assert:
+        that:
+          - table_30200.stdout is not search("blackhole 198.53.100.18
+            proto static scope link metric 20")
+          - table_30200.stdout is not search("prohibit 198.53.100.10
+            proto static scope link metric 30")
+          - table_30200.stdout is not search("unreachable 198.53.100.12
+            proto static scope link metric 24")
+        msg: "the route table 30200 contains the type routes"
+
+    - name: Assert that the route table 30600 still contains the type routes
+      assert:
+        that:
+          - table_30600.stdout is search("blackhole 2001:db8::4
+            dev lo proto static metric 2 pref medium")
+          - table_30600.stdout is search("prohibit 2001:db8::6
+            dev lo proto static metric 4 pref medium")
+        msg: "the route table 30600 does not exist or does not contain the
+          type routes"
+
+- name: Import the playbook 'down_profile+delete_interface.yml'
+  import_playbook: down_profile+delete_interface.yml
+  vars:
+    profile: "{{ interface }}"
+# FIXME: assert profile/device down
+- name: Import the playbook 'remove_profile.yml'
+  import_playbook: remove_profile.yml
+  vars:
+    profile: "{{ interface }}"
+- name: Assert device and profile are absent
+  hosts: all
+  tasks:
+    - name: Include the task 'assert_profile_absent.yml'
+      include_tasks: tasks/assert_profile_absent.yml
+      vars:
+        profile: "{{ interface }}"
+    - name: Include the task 'assert_device_absent.yml'
+      include_tasks: tasks/assert_device_absent.yml
+...