Add support for capturing renewals to dhcp discovery (#48242)

homeassistant/components/dhcp/__init__.py

@@ -18,6 +18,7 @@ from scapy.arch.common import compile_filter
 from scapy.config import conf
 from scapy.error import Scapy_Exception
 from scapy.layers.dhcp import DHCP
+from scapy.layers.inet import IP
 from scapy.layers.l2 import Ether
 from scapy.sendrecv import AsyncSniffer
 
@@ -41,7 +42,7 @@ from homeassistant.helpers.event import (
     async_track_time_interval,
 )
 from homeassistant.loader import async_get_dhcp
-from homeassistant.util.network import is_link_local
+from homeassistant.util.network import is_invalid, is_link_local, is_loopback
 
 from .const import DOMAIN
 
@@ -93,8 +94,14 @@ class WatcherBase:
 
     def process_client(self, ip_address, hostname, mac_address):
         """Process a client."""
-        if is_link_local(make_ip_address(ip_address)):
-            # Ignore self assigned addresses
+        made_ip_address = make_ip_address(ip_address)
+
+        if (
+            is_link_local(made_ip_address)
+            or is_loopback(made_ip_address)
+            or is_invalid(made_ip_address)
+        ):
+            # Ignore self assigned addresses, loopback, invalid
             return
 
         data = self._address_data.get(ip_address)
@@ -318,7 +325,7 @@ class DHCPWatcher(WatcherBase):
             # DHCP request
             return
 
-        ip_address = _decode_dhcp_option(options, REQUESTED_ADDR)
+        ip_address = _decode_dhcp_option(options, REQUESTED_ADDR) or packet[IP].src
         hostname = _decode_dhcp_option(options, HOSTNAME)
         mac_address = _format_mac(packet[Ether].src)
 

homeassistant/util/network.py

@@ -44,6 +44,11 @@ def is_local(address: IPv4Address | IPv6Address) -> bool:
     return is_loopback(address) or is_private(address)
 
 
+def is_invalid(address: IPv4Address | IPv6Address) -> bool:
+    """Check if an address is invalid."""
+    return bool(address == ip_address("0.0.0.0"))
+
+
 def is_ip_address(address: str) -> bool:
     """Check if a given string is an IP address."""
     try:

tests/components/dhcp/test_init.py

@@ -50,6 +50,36 @@ RAW_DHCP_REQUEST = (
     b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
 )
 
+# iRobot-AE9EC12DD3B04885BCBFA36AFB01E1CC 50:14:79:03:85:2c 192.168.1.120
+RAW_DHCP_RENEWAL = (
+    b"\x00\x15\x5d\x8e\xed\x02\x50\x14\x79\x03\x85\x2c\x08\x00\x45\x00"
+    b"\x01\x8e\x51\xd2\x40\x00\x40\x11\x63\xa1\xc0\xa8\x01\x78\xc0\xa8"
+    b"\x01\x23\x00\x44\x00\x43\x01\x7a\x12\x09\x01\x01\x06\x00\xd4\xea"
+    b"\xb2\xfd\xff\xff\x00\x00\xc0\xa8\x01\x78\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x50\x14\x79\x03\x85\x2c\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    b"\x00\x00\x00\x00\x00\x00\x63\x82\x53\x63\x35\x01\x03\x39\x02\x05"
+    b"\xdc\x3c\x45\x64\x68\x63\x70\x63\x64\x2d\x35\x2e\x32\x2e\x31\x30"
+    b"\x3a\x4c\x69\x6e\x75\x78\x2d\x33\x2e\x31\x38\x2e\x37\x31\x3a\x61"
+    b"\x72\x6d\x76\x37\x6c\x3a\x51\x75\x61\x6c\x63\x6f\x6d\x6d\x20\x54"
+    b"\x65\x63\x68\x6e\x6f\x6c\x6f\x67\x69\x65\x73\x2c\x20\x49\x6e\x63"
+    b"\x20\x41\x50\x51\x38\x30\x30\x39\x0c\x27\x69\x52\x6f\x62\x6f\x74"
+    b"\x2d\x41\x45\x39\x45\x43\x31\x32\x44\x44\x33\x42\x30\x34\x38\x38"
+    b"\x35\x42\x43\x42\x46\x41\x33\x36\x41\x46\x42\x30\x31\x45\x31\x43"
+    b"\x43\x37\x08\x01\x21\x03\x06\x1c\x33\x3a\x3b\xff"
+)
+
 
 async def test_dhcp_match_hostname_and_macaddress(hass):
     """Test matching based on hostname and macaddress."""
@@ -76,6 +106,31 @@ async def test_dhcp_match_hostname_and_macaddress(hass):
     }
 
 
+async def test_dhcp_renewal_match_hostname_and_macaddress(hass):
+    """Test renewal matching based on hostname and macaddress."""
+    dhcp_watcher = dhcp.DHCPWatcher(
+        hass,
+        {},
+        [{"domain": "mock-domain", "hostname": "irobot-*", "macaddress": "501479*"}],
+    )
+
+    packet = Ether(RAW_DHCP_RENEWAL)
+
+    with patch.object(hass.config_entries.flow, "async_init") as mock_init:
+        dhcp_watcher.handle_dhcp_packet(packet)
+        # Ensure no change is ignored
+        dhcp_watcher.handle_dhcp_packet(packet)
+
+    assert len(mock_init.mock_calls) == 1
+    assert mock_init.mock_calls[0][1][0] == "mock-domain"
+    assert mock_init.mock_calls[0][2]["context"] == {"source": "dhcp"}
+    assert mock_init.mock_calls[0][2]["data"] == {
+        dhcp.IP_ADDRESS: "192.168.1.120",
+        dhcp.HOSTNAME: "irobot-ae9ec12dd3b04885bcbfa36afb01e1cc",
+        dhcp.MAC_ADDRESS: "50147903852c",
+    }
+
+
 async def test_dhcp_match_hostname(hass):
     """Test matching based on hostname only."""
     dhcp_watcher = dhcp.DHCPWatcher(

tests/util/test_network.py

@@ -33,6 +33,12 @@ def test_is_link_local():
     assert not network_util.is_link_local(ip_address("127.0.0.1"))
 
 
+def test_is_invalid():
+    """Test invalid address."""
+    assert network_util.is_invalid(ip_address("0.0.0.0"))
+    assert not network_util.is_invalid(ip_address("127.0.0.1"))
+
+
 def test_is_local():
     """Test local addresses."""
     assert network_util.is_local(ip_address("192.168.0.1"))