fix(qbittorrent): prevent recursive routing with blackhole route in table 1000

Agent-Logs-Url: https://github.com/alexbelgium/hassio-addons/sessions/14f8993e-d073-4a6b-8c36-40ebf1b0e396

Co-authored-by: alexbelgium <44178713+alexbelgium@users.noreply.github.com>

qbittorrent/CHANGELOG.md

@@ -1,10 +1,6 @@
-## 5.2.0-18 (13-05-2026)
-- Simplify VPN endpoint route pinning to minimal helpers (single endpoint, no tracking list).
+## 5.2.0-19 (13-05-2026)
+- OpenVPN: simplify recursive routing fix — use a single blackhole route for the VPN server IP in table 1000 (no AWK, no ipcalc, no physical device detection required)
 
-## 5.2.0-17 (13-05-2026)
-- Fix VPN endpoint routing by pinning OpenVPN/WireGuard server IPs to the pre-VPN main route, preventing recursive tunnel routing drops.
-
-## 5.2.0-16 (13-05-2026)
 - Minor bugs fixed
 
 ## 5.2.0-2 (2026-05-10)

qbittorrent/config.yaml

@@ -143,4 +143,4 @@ schema:
 slug: qbittorrent
 udev: true
 url: https://github.com/alexbelgium/hassio-addons
-version: "5.2.0-18"
+version: "5.2.0-19"

qbittorrent/rootfs/usr/local/sbin/vpn

@@ -149,28 +149,6 @@ _resolve_hostname() {
     echo "${ips[@]}"
 }
 
-_endpoint_route_add() {
-    local ip="$1"
-    local rt via dev
-    rt="$(ip route get "${ip}" 2>/dev/null | head -n1)"
-    via="$(awk '{for(i=1;i<=NF;i++) if($i=="via"){print $(i+1);exit}}' <<< "${rt}")"
-    dev="$(awk '{for(i=1;i<=NF;i++) if($i=="dev"){print $(i+1);exit}}' <<< "${rt}")"
-    [ -z "${dev}" ] && { bashio::log.error "No route to VPN endpoint ${ip}."; return 1; }
-    if [ -n "${via}" ]; then
-        ip route replace "${ip}" via "${via}" dev "${dev}" || return 1
-    else
-        ip route replace "${ip}" dev "${dev}" || return 1
-    fi
-    bashio::log.info "Pinned VPN endpoint ${ip} to pre-VPN route (dev ${dev})."
-}
-
-_endpoint_route_del() {
-    local ip
-    ip="$(cat "${config["EndpointIPFile"]}" 2>/dev/null)"
-    [ -n "${ip}" ] && ip route del "${ip}" 2>/dev/null || true
-    rm -f "${config["EndpointIPFile"]}" || true
-}
-
 _routing_add() {
     bashio::log.info "Adding routing rules for VPN interface ${config["Interface"]}..."
 
@@ -366,8 +344,6 @@ _wireguard_up() {
     fi
 
     _cmd "ip link set ${config["Interface"]} up" || return 1
-    _endpoint_route_add "${config["EndpointIP"]}" || return 1
-    echo "${config["EndpointIP"]}" > "${config["EndpointIPFile"]}"
 
     # Add routing rules for VPN interface and DNS servers
     _routing_add || return 1
@@ -382,7 +358,6 @@ _wireguard_up() {
 }
 
 _wireguard_down() {
-    _endpoint_route_del || true
     # Update resolv.conf to remove VPN DNS servers
     _resolvconf "reset" || true
     # Remove routing rules for VPN interface and DNS servers
@@ -424,7 +399,6 @@ wireguard() {
     config["Interface"]="${interface}"
     config["ConfigFile"]="${config_file}"
     config["Table"]="${config["Table"]:-1000}"
-    config["EndpointIPFile"]="${WIREGUARD_STATE_DIR}/endpoint-ip"
     config["ListenPort"]="${config["ListenPort"]:-51820}"
     config["EndpointHost"]="${config["Endpoint"]%:*}"
     config["EndpointPort"]="${config["Endpoint"]##*:}"
@@ -511,8 +485,6 @@ _openvpn_check() {
 }
 
 _openvpn_up() {
-    local endpoint_ip result=0
-
     bashio::log.warning "This script force OpenvPN to ignore any routes and DNS settings pushed by the server."
     bashio::log.warning "Default route will be inserted into custom routing table: ${config["Table"]}"
     bashio::log.warning "This routing table will be used for traffic from the VPN interface and to the configured DNS servers."
@@ -526,15 +498,6 @@ _openvpn_up() {
     echo "${config["MySelf"]} openvpn postdown" >> ${config["PostDownScript"]}
     chmod 755 ${config["PostDownScript"]}
 
-    endpoint_ip="$(awk '/^[[:space:]]*remote[[:space:]]/ {print $2; exit}' "${config["ConfigFile"]}")"
-    if [ -n "${endpoint_ip}" ]; then
-        _check_host "${endpoint_ip}" || result=$?
-        [ "${result}" -eq 3 ] && endpoint_ip="$(_resolve_hostname "${endpoint_ip}" | awk '{print $1}')"
-        if [ -n "${endpoint_ip}" ]; then
-            _endpoint_route_add "${endpoint_ip}" && echo "${endpoint_ip}" > "${config["EndpointIPFile"]}"
-        fi
-    fi
-
     # Define logging
     declare -A verbosity=(
         ["fatal"]=1
@@ -570,12 +533,34 @@ _openvpn_up() {
 _openvpn_down() {
     # Terminate OpenVPN process
     pkill -f "openvpn --config ${config["ConfigFile"]}" || true
-    _endpoint_route_del || true
     # Safety-net cleanup in case the --down callback was never invoked
     _routing_del || true
+    # Safety-net: remove blackhole route for VPN server if postdown was never invoked
+    if [ -f "${OPENVPN_STATE_DIR}/server_ip" ]; then
+        local saved_ip
+        saved_ip=$(cat "${OPENVPN_STATE_DIR}/server_ip" 2>/dev/null || true)
+        if [ -n "${saved_ip}" ]; then
+            ip -4 route del blackhole "${saved_ip}/32" table "${config["Table"]}" 2>/dev/null || true
+        fi
+        rm -f "${OPENVPN_STATE_DIR}/server_ip"
+    fi
 }
 
-_openpvn_postup() {
+_openvpn_postup() {
+    # Prevent recursive routing: add a blackhole route for the VPN server IP in
+    # table 1000. qBittorrent is bound to tun0, so its traffic is policy-routed
+    # into table 1000 (rule: from <tun_ip> -> table 1000).  Without this, packets
+    # destined for the VPN server go through tun0, OpenVPN detects the loop and
+    # drops them.  The blackhole makes qBittorrent's traffic to the server IP fail
+    # immediately (EHOSTUNREACH) instead of looping.  OpenVPN itself is not bound
+    # to tun0, so its traffic uses the main table and reaches the server normally.
+    if [ -n "${trusted_ip:-}" ]; then
+        bashio::log.info "Adding blackhole route for VPN server ${trusted_ip} in table ${config["Table"]} to prevent recursive routing."
+        ip -4 route add blackhole "${trusted_ip}/32" table "${config["Table"]}" 2>/dev/null \
+            && echo "${trusted_ip}" > "${OPENVPN_STATE_DIR}/server_ip" \
+            || bashio::log.warning "Could not add blackhole route for VPN server ${trusted_ip}."
+    fi
+
     # Add routing rules for VPN interface and DNS servers
     _routing_add || return 1
     # Add firewall rules for VPN interface (only when UPnP port mapping is enabled)
@@ -586,7 +571,19 @@ _openpvn_postup() {
     _resolvconf "update" || return 1
 }
 
-_openpvn_postdown() {
+_openvpn_postdown() {
+    # Remove blackhole route for VPN server (added in postup to prevent recursive routing)
+    local server_ip=""
+    if [ -n "${trusted_ip:-}" ]; then
+        server_ip="${trusted_ip}"
+    elif [ -f "${OPENVPN_STATE_DIR}/server_ip" ]; then
+        server_ip=$(cat "${OPENVPN_STATE_DIR}/server_ip" 2>/dev/null || true)
+    fi
+    if [ -n "${server_ip}" ]; then
+        ip -4 route del blackhole "${server_ip}/32" table "${config["Table"]}" 2>/dev/null || true
+        rm -f "${OPENVPN_STATE_DIR}/server_ip"
+    fi
+
     # Update resolv.conf to remove VPN DNS servers
     _resolvconf "reset" || true
     # Remove routing rules for VPN interface and DNS servers
@@ -595,7 +592,6 @@ _openpvn_postdown() {
     if bashio::config.true 'vpn_upnp_enabled'; then
         _firewall_del || true
     fi
-    _endpoint_route_del || true
 }
 
 openvpn() {
@@ -625,7 +621,6 @@ openvpn() {
     config["Interface"]="${interface}"
     config["ConfigFile"]="${config_file}"
     config["Table"]="${config["Table"]:-1000}"
-    config["EndpointIPFile"]="${OPENVPN_STATE_DIR}/endpoint-ip"
     config["PostUpScript"]="${OPENVPN_STATE_DIR}/up.sh"
     config["PostDownScript"]="${OPENVPN_STATE_DIR}/down.sh"
 
@@ -644,10 +639,10 @@ openvpn() {
         bashio::log.info "OpenVPN on interface ${config["Interface"]} is down."
         bashio::exit.ok 'OpenVPN stopped.'
     elif [ "${mode}" = "postup" ]; then
-        _openpvn_postup
+        _openvpn_postup
         bashio::exit.ok 'OpenVPN routes added.'
     elif [ "${mode}" = "postdown" ]; then
-        _openpvn_postdown
+        _openvpn_postdown
         bashio::exit.ok 'OpenVPN routes deleted.'
     else
         bashio::log.error "Invalid OpenVPN mode specified. Use 'up', 'down', 'postup', or 'postdown'."