Wifi wds

board/aarch64/bananapi-bpi-r3/rootfs/etc/modprobe.d/mt7915e-wed.conf

@@ -0,0 +1,2 @@
+# Wireless Ethernet Dispatch, lets the PPE forward offloaded flows to the radios
+options mt7915e wed_enable=1

board/aarch64/bananapi-bpi-r3/uboot/mt7986-env.dtsi

@@ -13,7 +13,7 @@
                        fdt_addr_r = "0x43f00000";
                        kernel_addr_r = "0x44000000";
                        scriptaddr = "0x48000000";
-                       ramdisk_addr_r = "0x4A000000";
+                       ramdisk_addr_r = "0x50000000";
 
 		en8811h_fw_part = "0#en8811h_fw";
 		en8811h_fw_dm_dir = "EthMD32.dm.bin";

board/common/rootfs/usr/libexec/infix/iw.py

@@ -486,6 +486,29 @@ def parse_dev():
     return result
 
 
+def parse_wds_ports(ifname):
+    """
+    List the WDS ports of an access point: the AP/VLAN interfaces on the
+    same PHY that carry its MAC address.
+    Returns: [ifname, ...]
+    """
+    info = parse_interface_info(ifname)
+    mac = info.get('mac')
+    ports = []
+
+    for phy, ifaces in parse_dev().items():
+        if ifname not in ifaces:
+            continue
+        for dev in ifaces:
+            if dev == ifname:
+                continue
+            devinfo = parse_interface_info(dev)
+            if devinfo.get('iftype') == 'AP/VLAN' and devinfo.get('mac') == mac:
+                ports.append(dev)
+
+    return ports
+
+
 def parse_link(ifname):
     """
     Parse 'iw dev <name> link' output for station mode
@@ -629,6 +652,7 @@ def main():
                 'station': 'Get connected stations in AP mode (requires interface)',
                 'link': 'Get link info in station mode (requires interface)',
                 'mesh': 'Get mesh parameters in mesh point mode (requires interface)',
+                'wds': 'List the WDS ports of an access point (requires interface)',
                 'caps': 'Get HT/VHT capability bitmasks (requires PHY/radio)'
             },
             'examples': [
@@ -677,6 +701,11 @@ def main():
                 data = {'error': 'mesh command requires interface argument'}
             else:
                 data = parse_mesh_param(sys.argv[2])
+        elif command == 'wds':
+            if len(sys.argv) < 3:
+                data = {'error': 'wds command requires interface argument'}
+            else:
+                data = parse_wds_ports(sys.argv[2])
         elif command == 'survey':
             if len(sys.argv) < 3:
                 data = {'error': 'survey command requires interface argument'}

doc/ChangeLog.md

@@ -30,6 +30,26 @@ All notable changes to the project are documented in this file.
 - LLDP neighbors were listed without their system name, descriptions, and
   capabilities, in the CLI, the WebUI, and the operational datastore
 
+### Added
+
+- WiFi 4-address (WDS) links: a station with `wds` enabled can be a bridge
+  port, and an access point gets a `wds-link` interface per remote station
+  to bridge it.  Together they build wireless bridges and repeaters, see
+  [WDS Backhaul and Repeaters][wds].  The station leaf `peer-bssid` pins a
+  station to one access point
+- MT7986 boards (Banana Pi BPI-R3, BPI-R3 Mini, Acer Connect Vero W6m):
+  WiFi hardware offloading is now active, which lowers the CPU load of
+  WiFi traffic
+
+### Fixes
+
+- Fix #1679: a WiFi station set up on an interface that was in scan-only
+  mode, as in the Raspberry Pi 4 factory configuration, did not connect
+  until the device was rebooted.  Changes to a station's or mesh point's
+  settings now take effect on commit
+
+[wds]: https://www.kernelkit.org/infix/latest/wifi/#wds-backhaul-and-repeaters
+
 [v26.09.0][] - 2026-09-30
 -------------------------
 

doc/wifi.md

@@ -1,7 +1,8 @@
 # Wi-Fi (Wireless LAN)
 
-Infix includes comprehensive Wi-Fi support for both client (Station) and
-Access Point modes. When a compatible Wi-Fi adapter is detected, the system
+Infix supports Wi-Fi as a client (Station), as an Access Point, as an
+802.11s mesh point, and as a 4-address (WDS) link for wireless bridges
+and repeaters.  When a compatible Wi-Fi adapter is detected, the system
 automatically creates a WiFi radio (PHY) in factory-config, that can
 host virtual interfaces.
 
@@ -16,7 +17,7 @@ Infix uses a two-layer WiFi architecture:
 
 2. **WiFi Interface (Network layer)**: Virtual interface on a radio
      - Configured via `infix-interfaces` module
-     - Can operate in Station (client) or Access Point mode
+     - Operates in Station (client), Access Point, Mesh Point or WDS link mode
      - Each interface references a parent radio
 
 ## Naming Conventions
@@ -44,7 +45,9 @@ Where `N` is a number (0, 1, 2, ...).
 
 - USB hotplug is not supported - adapters must be present at boot
 - Interface naming may be inconsistent with multiple USB Wi-Fi adapters
-- AP and Station modes cannot be mixed on the same radio
+- A station and access points on the same radio must share a channel: the
+  station follows its access point, so pin the radio to that channel on
+  both ends.  See [WDS Backhaul and Repeaters](#wds-backhaul-and-repeaters)
 
 ## Supported Wi-Fi Adapters
 
@@ -704,9 +707,8 @@ Repeat for all APs that should participate in the roaming group.
 
 IEEE 802.11s is a wireless mesh networking standard operating at Layer 2.
 Mesh nodes form peer links directly with each other and route traffic
-using HWMP (Hybrid Wireless Mesh Protocol), which is built into the
-Linux mac80211 subsystem.  There is no central controller; nodes
-discover peers and find paths on their own.
+using HWMP (Hybrid Wireless Mesh Protocol).  There is no central
+controller; nodes discover peers and find paths on their own.
 
 The standard defines two node roles:
 
@@ -718,11 +720,13 @@ The standard defines two node roles:
 In practice, a node bridging the mesh interface to a LAN acts as a mesh
 portal.
 
+For a backhaul with a single root, where multi-hop and self-healing are
+not needed, see [WDS Backhaul and Repeaters](#wds-backhaul-and-repeaters).
+That variant can use WiFi hardware offloading, mesh cannot.
+
 > [!NOTE]
-> Not all WiFi hardware supports 802.11s mesh.  The driver must implement
-> mesh point mode in mac80211.  Check your adapter's capabilities with
-> `iw phy <phy> info` and look for "mesh point" under "Supported interface
-> modes".
+> Not all WiFi hardware supports 802.11s mesh, see the adapter list
+> under [Supported Wi-Fi Adapters](#supported-wi-fi-adapters).
 
 ### 802.11s vs EasyMesh
 
@@ -733,10 +737,10 @@ portal.
 | **Single point of failure** | None                     | Controller                     |
 | **Multi-hop**               | True N-hop               | Limited (1-2 hops)             |
 | **Vendor lock-in**          | None                     | Common                         |
-| **Linux support**           | Kernel-native (mac80211) | Requires proprietary firmware  |
+| **Vendor software**         | None needed              | Required                       |
 
-Infix uses 802.11s because it runs entirely in the kernel with no
-proprietary components.
+Infix uses 802.11s because it is an open standard that works across
+vendors without proprietary components.
 
 ### Mesh configuration
 
@@ -808,6 +812,114 @@ With 802.11r/k/v roaming enabled on the APs (same SSID, same
 passphrase, same mobility domain), clients hand off between nodes while
 the mesh carries backhaul traffic.
 
+## WDS Backhaul and Repeaters
+
+A WiFi station normally carries only its own traffic and cannot be a
+bridge port.  In 4-address mode, also called WDS, it can forward traffic
+for the devices behind it.  That is what makes a device with a station
+and an access point a repeater, and a device with a station and wired
+ports a wireless bridge.
+
+Both ends take part.  The satellite enables `wds` on its station.  The
+root accepts the station on one of its access points and gives it a
+`wds-link` interface: a bridge port, one per satellite, created by
+configuration and tied to the satellite's MAC address.
+
+Compared to an [802.11s mesh](#80211s-mesh-point-mode), a WDS backhaul
+is a star with one root, without multi-hop or self-healing.  In return
+it is a plain access point and station link, which WiFi hardware
+offloading supports where mesh is not.
+
+### Root: access point with WDS ports
+
+On the root, two kinds of interface share the job.  The access point is
+the one the satellites connect to: it advertises the backhaul SSID and
+handles authentication, and there is one per radio.  Each `wds-link`
+is the port for one satellite: that is where its traffic appears and
+what you put in the bridge.  With two satellites on `radio1`:
+
+```
+radio1
+ ├── backhaul    access point, the SSID the satellites connect to
+ ├── wds-jaffa   port for jaffa, bridge port
+ └── wds-tauri   port for tauri, bridge port
+```
+
+Give the backhaul its own SSID, advertised by the root only, so the
+satellites can land nowhere else.  For each satellite, add a `wds-link`
+interface naming the access point and the satellite's station MAC
+address, and make it a port of the bridge.  The interface uses the
+access point's radio and MAC address, so it takes neither a `radio` nor
+a `custom-phys-address`.
+
+<pre class="cli"><code>admin@root:/config/> <b>edit interface backhaul</b>
+admin@root:/config/interface/backhaul/> <b>set wifi radio radio1</b>
+admin@root:/config/interface/backhaul/> <b>set wifi access-point ssid my-backhaul</b>
+admin@root:/config/interface/backhaul/> <b>set wifi access-point security secret backhaul-key</b>
+admin@root:/config/interface/backhaul/> <b>end</b>
+admin@root:/config/> <b>edit interface wds-jaffa</b>
+admin@root:/config/interface/wds-jaffa/> <b>set type wifi</b>
+admin@root:/config/interface/wds-jaffa/> <b>set wifi wds-link access-point backhaul</b>
+admin@root:/config/interface/wds-jaffa/> <b>set wifi wds-link peer-address 02:13:37:13:37:12</b>
+admin@root:/config/interface/wds-jaffa/> <b>set bridge-port bridge br0</b>
+admin@root:/config/interface/wds-jaffa/> <b>leave</b>
+</code></pre>
+
+VLANs and other bridge port settings are configured on the `wds-link`
+interface like on any other port.  The port is down until the satellite
+connects, and goes down again when it leaves, or within about half a
+minute if the satellite disappears without notice:
+
+<pre class="cli"><code>admin@root:/> <b>show interface wds-jaffa</b>
+name               : wds-jaffa
+type               : wifi
+operational status : up
+higher-layer-if    : br0
+mode               : wds-link
+connected          : yes
+signal             : -48 dBm (good)
+</code></pre>
+
+### Satellite: 4-address station
+
+On the satellite, configure a station for the backhaul SSID with `wds`
+enabled and make it a bridge port, next to the wired ports and any local
+access points.  `peer-bssid` is optional and pins the station to the
+root's access point:
+
+<pre class="cli"><code>admin@jaffa:/config/> <b>edit interface uplink</b>
+admin@jaffa:/config/interface/uplink/> <b>set wifi radio radio1</b>
+admin@jaffa:/config/interface/uplink/> <b>set wifi station ssid my-backhaul</b>
+admin@jaffa:/config/interface/uplink/> <b>set wifi station wds true</b>
+admin@jaffa:/config/interface/uplink/> <b>set wifi station peer-bssid 02:13:37:13:37:01</b>
+admin@jaffa:/config/interface/uplink/> <b>set wifi station security secret backhaul-key</b>
+admin@jaffa:/config/interface/uplink/> <b>set bridge-port bridge br0</b>
+admin@jaffa:/config/interface/uplink/> <b>leave</b>
+</code></pre>
+
+A station without `wds` cannot be a bridge port, the configuration is
+rejected.
+
+### Repeater
+
+A repeater is a satellite that also runs an access point for clients,
+bridged with the backhaul station.  The station and the access point
+can share a radio, but then all radios in the backhaul must use the same
+channel: the station follows the root's channel and the local access
+point has a fixed one.  A channel change on the root, for example from
+radar detection, leaves the satellites disconnected until they are
+reconfigured.
+
+Clients on a repeater keep their own MAC addresses, so DHCP reservations
+and per-port VLANs work as on a wired network.  With the same client
+SSID on the root and the repeaters, the [roaming
+features](#fast-roaming-between-access-points) apply as usual.  Keep the
+backhaul SSID separate from the client SSIDs, or a satellite may connect
+to another satellite instead of the root.
+
+A satellite with both a WDS backhaul and a cable to the same LAN forms a
+loop, as with any two bridge ports to the same network.
+
 ## Troubleshooting
 
 Use `show interface wifi0` to verify signal strength and connection status.

package/feature-wifi/wifimedium

@@ -13,7 +13,9 @@ This daemon is that process.  On each DUT it:
   * registers on the "mac80211_hwsim" genl family and receives every frame the
     local radios transmit (HWSIM_CMD_FRAME),
   * acknowledges each transmit back to the kernel (HWSIM_CMD_TX_INFO_FRAME) so
-    mac80211's TX path completes, and
+    mac80211's TX path completes.  A unicast frame is only acknowledged if its
+    receiver has been heard on the medium recently, so a station that vanishes
+    stops acking like on real RF and the AP's inactivity probing works, and
   * relays the frame per radio: each radio (phy radioN) is paired by name with a
     carrier NIC (netdev radioN) that joins one multicast "cell" -- a QEMU socket
     multicast group shared by every DUT's radioN (see test/virt/quad and
@@ -181,9 +183,11 @@ class Netlink:
             attrs += put_attr(HWSIM_ATTR_FREQ, struct.pack("=I", freq))
         self._send(self.family_id, HWSIM_CMD_FRAME, attrs)
 
-    def tx_ack(self, transmitter, flags, tx_info, tx_info_flags, cookie):
+    def tx_ack(self, transmitter, flags, tx_info, tx_info_flags, cookie, ack=True):
+        if ack:
+            flags |= HWSIM_TX_STAT_ACK
         attrs = put_attr(HWSIM_ATTR_ADDR_TRANSMITTER, transmitter)
-        attrs += put_attr(HWSIM_ATTR_FLAGS, struct.pack("=I", flags | HWSIM_TX_STAT_ACK))
+        attrs += put_attr(HWSIM_ATTR_FLAGS, struct.pack("=I", flags))
         attrs += put_attr(HWSIM_ATTR_SIGNAL, struct.pack("=i", RX_SIGNAL))
         if tx_info:
             attrs += put_attr(HWSIM_ATTR_TX_INFO, tx_info)
@@ -232,7 +236,10 @@ def open_medium(ifname):
     # The carrier NIC is unconfigured (it is not a real DUT port), so Infix
     # leaves it administratively down -- a raw packet socket on a down link
     # carries no frames.  Bring it up; wifimedium owns the medium, like hwsim0.
-    ifup(ifname)
+    # A full-size data frame is a 1500 byte MSDU plus 802.11 header, mesh
+    # control, encryption and LLC, and A-MSDUs are larger still, so the
+    # carrier needs a far larger MTU than the default 1500.
+    ifup(ifname, mtu=9000)
     sock = socket.socket(socket.AF_PACKET, socket.SOCK_RAW,
                          socket.htons(ETH_P_WIFIMEDIUM))
     sock.bind((ifname, ETH_P_WIFIMEDIUM))
@@ -251,6 +258,25 @@ def open_medium(ifname):
 # raw 802.11 frame.
 WIRE = struct.Struct("=6sI")
 
+# Transmitter addresses heard on the medium and when.  mac80211 stations send
+# a keep-alive at least every 30 s when idle, so one not heard for twice that
+# is gone and frames to it go unacknowledged.
+ALIVE_TIMEOUT = 60.0
+seen = {}
+
+
+def heard(frame):
+    if len(frame) >= 16:
+        seen[frame[10:16]] = time.monotonic()
+
+
+def acked(frame):
+    """Would the receiver of this frame acknowledge it?"""
+    if len(frame) < 10 or frame[4] & 1:
+        return True          # multicast: no ack expected, keep hwsim's default
+    last = seen.get(frame[4:10])
+    return last is not None and time.monotonic() - last < ALIVE_TIMEOUT
+
 
 def wait_radios_renamed(timeout=20):
     """Wait until the hwsim phys have been renamed phyN -> radioN.
@@ -307,8 +333,10 @@ def discover_radios():
     return radios
 
 
-def ifup(ifname):
-    """Bring an interface up (best effort)."""
+def ifup(ifname, mtu=None):
+    """Bring an interface up (best effort), optionally with a larger MTU."""
+    if mtu:
+        subprocess.run(["ip", "link", "set", ifname, "mtu", str(mtu)], check=False)
     subprocess.run(["ip", "link", "set", ifname, "up"], check=False)
 
 
@@ -364,13 +392,17 @@ def main():
                         # Complete the kernel TX path regardless of delivery.
                         nl.tx_ack(tx, flags, a.get(HWSIM_ATTR_TX_INFO),
                                   a.get(HWSIM_ATTR_TX_INFO_FLAGS),
-                                  a.get(HWSIM_ATTR_COOKIE))
+                                  a.get(HWSIM_ATTR_COOKIE), acked(frame))
                         # Send only onto the transmitting radio's own carrier.
                         r = by_addr1.get(tx)
                         if r:
-                            r["sock"].send(ETH_BROADCAST + r["mac"] + ETYPE +
-                                           WIRE.pack(tx, freq) + frame)
-                            dbg(f"tx {r['name']} freq={freq} len={len(frame)}")
+                            try:
+                                r["sock"].send(ETH_BROADCAST + r["mac"] + ETYPE +
+                                               WIRE.pack(tx, freq) + frame)
+                                dbg(f"tx {r['name']} freq={freq} len={len(frame)}")
+                            except OSError as e:
+                                # Lost on the air, like a collision would be.
+                                log(f"tx {r['name']} len={len(frame)} dropped: {e}")
                         else:
                             dbg(f"tx from unknown radio {tx.hex()} -- dropped")
                 off += nla_align(mlen)
@@ -389,6 +421,7 @@ def main():
                 continue
             tx, freq = WIRE.unpack_from(pkt, 14)
             frame = pkt[14 + WIRE.size:]
+            heard(frame)
             # Inject into THIS radio only -- its carrier is its cell.
             nl.inject(r["addr1"], frame, freq)
             dbg(f"rx {r['name']} tx={tx.hex()} freq={freq} len={len(frame)}")