munet: autonumber loopbacks

Configure loopback addresses through the `ip` and `ipv6` node config.
Loopbacks are automatically configured by `networks-autonumber`.

Signed-off-by: Liam Brady <lbrady@labn.net>

Author: liambrady

README.org

@@ -46,6 +46,8 @@ module: labn-munet-config
   |     +--rw new-window?    boolean
   |     +--rw top-level?     boolean
   +--rw kinds* [name]
+  |  +--rw ip?                  string
+  |  +--rw ipv6?                string
   |  +--rw merge*               string
   |  +--rw cap-add*             string
   |  +--rw cap-remove*          string
@@ -134,6 +136,8 @@ module: labn-munet-config
   |  +--rw nodes* [name]
   |     +--rw id?                  uint32
   |     +--rw kind?                -> ../../../kinds/name
+  |     +--rw ip?                  string
+  |     +--rw ipv6?                string
   |     +--rw cap-add*             string
   |     +--rw cap-remove*          string
   |     +--rw cmd?                 string
@@ -540,6 +544,14 @@ munet>
 
     grouping common-node {
       description "Common node properties";
+      leaf ip {
+          type string;
+          description "IPv4 address and mask for the loopback address.";
+      }
+      leaf ipv6 {
+          type string;
+          description "IPv6 address and mask for the loopback address.";
+      }
       leaf-list cap-add {
         type string;
         description "Capabilities to add to a container.";
@@ -1153,4 +1165,3 @@ munet>
   [ -d /yang ] || DOCKER="sudo podman run --net=host -v $(pwd):/work docker.io/labn/org-rfc"
   if ! $DOCKER pyang -P build --lax-quote-checks -Werror --lint $module 2>&1; then echo FAIL; fi
 #+end_src
-

doc/source/config.rst

@@ -77,7 +77,7 @@ Topology
 --------
 
 The topology section defines the networks and nodes that make up the topology
-along withe a few global topology options.
+along with a few global topology options.
 
 .. pyang labn-munet-config.yang -f tree --tree-path=/topology
 
@@ -117,6 +117,8 @@ Tree diagram for node config::
    |  +--rw nodes* [name]
    |     +--rw id?            uint32
    |     +--rw kind?          -> ../../../kinds/name
+   |     +--rw ip?            string
+   |     +--rw ipv6?          string
    |     +--rw cap-add*       string
    |     +--rw cap-remove*    string
    |     +--rw cmd?           string

munet/munet-schema.json

@@ -69,6 +69,12 @@
               "type": "string"
             }
           },
+          "ip": {
+            "type": "string"
+          },
+          "ipv6": {
+            "type": "string"
+          },
           "cap-add": {
             "type": "array",
             "items": {
@@ -425,6 +431,12 @@
               "kind": {
                 "type": "string"
               },
+              "ip": {
+                "type": "string"
+              },
+              "ipv6": {
+                "type": "string"
+              },
               "cap-add": {
                 "type": "array",
                 "items": {

munet/native.py

@@ -59,13 +59,24 @@ class L3ContainerNotRunningError(MunetError):
 
 
 def get_loopback_ips(c, nid):
+    ips = []
     if ip := c.get("ip"):
         if ip == "auto":
-            return [ipaddress.ip_interface("10.255.0.0/32") + nid]
-        if isinstance(ip, str):
-            return [ipaddress.ip_interface(ip)]
-        return [ipaddress.ip_interface(x) for x in ip]
-    return []
+            assert nid < 0xFFFF  # Limited to 10.255.0.0/16 block
+            ips.append(ipaddress.ip_interface("10.255.0.0/32") + nid)
+        elif isinstance(ip, str):
+            ips.append(ipaddress.ip_interface(ip))
+        else:
+            ips.extend([ipaddress.ip_interface(x) for x in ip])
+    if ipv6 := c.get("ipv6"):
+        if ipv6 == "auto":
+            assert nid < 0xFFFF  # Same limit as ipv4 for simplicity
+            ips.append(ipaddress.ip_interface(f"fcfe:ffff:{nid:02x}::1/128"))
+        elif isinstance(ip, str):
+            ips.append(ipaddress.ip_interface(ipv6))
+        else:
+            ips.extend([ipaddress.ip_interface(x) for x in ipv6])
+    return ips
 
 
 def make_ip_network(net, inc):
@@ -94,6 +105,7 @@ def get_ip_network(c, brid, ipv6=False):
             return ifip
         except ValueError:
             return ipaddress.ip_network(ip)
+    assert brid < 0xFDFF  # Limited to 10.0.0.0/16 through 10.253.0.0/16 blocks
     if ipv6:
         return make_ip_interface("fc00::fe/64", brid)
     return make_ip_interface("10.0.0.254/24", brid)
@@ -779,12 +791,16 @@ def __init__(self, *args, unet=None, **kwargs):
             self.cmd_raises("sysctl -w net.ipv6.conf.all.disable_ipv6=0")
             self.cmd_raises("sysctl -w net.ipv6.conf.all.forwarding=1")
 
-        assert self.id < 0xFF * (0xFF - 0x7F)  # Beyond this, ipv4 address is invalid
+        assert self.id < 0x7FFF  # Limited to 10.254.0.0/16 block
         self.next_p2p_network = ipaddress.ip_network(
             f"10.254.{self.id & 0xFF}.{(self.id & 0x7F00) >> 7}/31"
         )
         self.next_p2p_network6 = ipaddress.ip_network(f"fcff:ffff:{self.id:02x}::/127")
 
+        if "ip" not in self.config and self.unet.autonumber:
+            self.config["ip"] = "auto"
+        if "ipv6" not in self.config and self.unet.autonumber and self.unet.ipv6_enable:
+            self.config["ipv6"] = "auto"
         self.loopback_ip = None
         self.loopback_ips = get_loopback_ips(self.config, self.id)
         self.loopback_ip = self.loopback_ips[0] if self.loopback_ips else None

tests/basic/munet.yaml

@@ -46,6 +46,8 @@ topology:
         which ping
         tail -f /dev/null
     - name: r3
+      ip:  "172.16.0.3/32"
+      ipv6: "fe8f:ffff:3::1/128"
       connections:
         - to: "net1"
         - to: "r2"

tests/basic/test_basic_topology.py

@@ -49,6 +49,9 @@ async def test_autonumber_ping(unet_perfunc):
     o = await r2.async_cmd_raises("ping -w1 -c1 10.254.2.1")
     logging.debug("r2 ping r3 p2p (10.254.2.1) output: %s", o)
 
+    o = await r2.async_cmd_raises("ping -w1 -c1 10.255.0.2")
+    logging.debug("r2 ping lo (10.255.0.2) output: %s", o)
+
     if unet.ipv6_enable:
         addr = "fc00:0:0:1::2"
         o = await r1.async_cmd_nostatus("ip -6 neigh show dev xyz0")
@@ -74,10 +77,27 @@ async def test_autonumber_ping(unet_perfunc):
         o = await r2.async_cmd_raises("ping -w1 -c1 fcff:ffff:2::1")
         logging.debug("r2 ping r3 p2p (fcff:ffff:2::1) output: %s", o)
 
+        o = await r2.async_cmd_raises("ping -w1 -c1 fcfe:ffff:2::1")
+        logging.debug("r2 ping lo (fcfe:ffff:2::1) output: %s", o)
+
         o = await r1.async_cmd_nostatus("ip -6 neigh show")
         logging.info("ip -6 neigh show: %s", o)
 
 
+@pytest.mark.parametrize(
+    "unet_perfunc", ["munet"], indirect=["unet_perfunc"]
+)
+async def test_basic_config(unet_perfunc):
+    unet = unet_perfunc
+    r3 = unet.hosts["r3"]
+
+    o = await r3.async_cmd_raises("ping -w1 -c1 172.16.0.3")
+    logging.debug("r1 ping lo (172.16.0.3) output: %s", o)
+
+    o = await r3.async_cmd_raises("ping -w1 -c1 fe8f:ffff:3::1")
+    logging.debug("r1 ping lo (fe8f:ffff:3::1) output: %s", o)
+
+
 @pytest.mark.parametrize("ipv6", [False, True])
 @pytest.mark.parametrize("unet_perfunc", [False, True], indirect=["unet_perfunc"])
 async def test_mtu_ping(unet_perfunc, astepf, ipv6):