Add LINSTOR controller and satellite helpers

src/xcp_storage/backends/linstor/controller.py

@@ -0,0 +1,72 @@
+# Copyright (C) 2026  Vates SAS
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+from xcp_storage.backends.linstor.satellite import LINSTOR_SATELLITE_PORT_PLAIN, LINSTOR_SATELLITE_PORT_SSL
+from xcp_storage.config.platform import get_exec_path
+from xcp_storage.utils.process import run_command
+from xcp_storage.utils.service import (
+    is_service_active,
+    restart_service,
+    start_service,
+    stop_service,
+)
+
+from xcp_storage.typing import Final, List
+
+# ==============================================================================
+
+LINSTOR_CONTROLLER_PORT_PLAIN: Final = 3370
+LINSTOR_CONTROLLER_PORT_SSL: Final = 3371
+
+# ------------------------------------------------------------------------------
+
+_EXEC_PATH_SS: Final = get_exec_path("/usr/sbin/ss", {"debian": "/usr/bin/ss"})
+
+_SERVICE_LINSTOR_CONTROLLER: Final = "linstor-controller"
+
+# ------------------------------------------------------------------------------
+
+class LinstorController:
+    @staticmethod
+    def get_addresses() -> List[str]:
+        stdout = run_command([
+            _EXEC_PATH_SS, "-tnpH", "state", "established",
+            f"( sport = :{LINSTOR_SATELLITE_PORT_PLAIN} or sport = :{LINSTOR_SATELLITE_PORT_SSL} )"
+        ], expected_ret_code=0)
+        return [
+            line.split()[3].rsplit(":", 1)[0]
+            for line in stdout.splitlines()
+        ]
+
+    @classmethod
+    def get_uri(cls) -> str:
+        # TODO(XCPNG-3033): On caller side, check that an IP address from the current pool is returned.
+        addresses = cls.get_addresses()
+        return "linstor://" + addresses[0] if addresses else ""
+
+    @staticmethod
+    def is_running() -> bool:
+        return is_service_active(_SERVICE_LINSTOR_CONTROLLER)
+
+    @staticmethod
+    def start() -> None:
+        start_service(_SERVICE_LINSTOR_CONTROLLER)
+
+    @staticmethod
+    def stop() -> None:
+        stop_service(_SERVICE_LINSTOR_CONTROLLER)
+
+    @staticmethod
+    def restart() -> None:
+        restart_service(_SERVICE_LINSTOR_CONTROLLER)

src/xcp_storage/backends/linstor/satellite.py

@@ -0,0 +1,45 @@
+# Copyright (C) 2026  Vates SAS
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+from xcp_storage.utils.service import (
+    disable_and_stop_service,
+    enable_and_start_service,
+    is_service_active,
+)
+
+from xcp_storage.typing import Final
+
+# ==============================================================================
+
+LINSTOR_SATELLITE_PORT_PLAIN: Final = 3366
+LINSTOR_SATELLITE_PORT_SSL: Final = 3367
+
+# ------------------------------------------------------------------------------
+
+_SERVICE_LINSTOR_SATELLITE: Final = "linstor-satellite"
+
+# ------------------------------------------------------------------------------
+
+class LinstorSatellite:
+    @staticmethod
+    def is_running() -> bool:
+        return is_service_active(_SERVICE_LINSTOR_SATELLITE)
+
+    @staticmethod
+    def enable_and_start() -> None:
+        enable_and_start_service(_SERVICE_LINSTOR_SATELLITE)
+
+    @staticmethod
+    def disable_and_stop() -> None:
+        disable_and_stop_service(_SERVICE_LINSTOR_SATELLITE)

src/xcp_storage/config/platform.py

@@ -12,7 +12,10 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-from xcp_storage.typing import Final
+from functools import lru_cache
+from pathlib import Path
+
+from xcp_storage.typing import Final, Mapping, Tuple
 
 # ==============================================================================
 # Attributes that depend on the execution environment.
@@ -21,3 +24,35 @@
 # ==============================================================================
 
 DEFAULT_FIREWALL_INPUT_CHAIN: Final = "xapi-INPUT"
+
+# ------------------------------------------------------------------------------
+
+_OS_RELEASE_PATH: Final = "/etc/os-release"
+
+@lru_cache(maxsize=None)
+def get_os_ids() -> Tuple[str, ...]:
+    """
+    Get the IDs of the current distribution, most specific first: `ID` followed
+    by the values of `ID_LIKE` (e.g. `("ubuntu", "debian")`). The result is
+    cached. An empty tuple is returned if `/etc/os-release` can't be read.
+    """
+
+    try:
+        lines = Path(_OS_RELEASE_PATH).read_text(encoding="utf-8").splitlines()
+    except OSError:
+        return ()
+
+    values = {}
+    for line in lines:
+        key, _separator, value = line.partition("=")
+        values[key.strip()] = value.strip().strip("\"'")
+
+    return tuple(values.get("ID", "").split() + values.get("ID_LIKE", "").split())
+
+def get_exec_path(default: str, by_os_id: Mapping[str, str]) -> str:
+    """
+    Get the path of an executable: the one registered for the first matching OS
+    ID, otherwise `default`.
+    """
+
+    return next((by_os_id[os_id] for os_id in get_os_ids() if os_id in by_os_id), default)

src/xcp_storage/network/socket.py

@@ -198,13 +198,18 @@ def create_client_sock(
     reuse_address: bool = True,
     keep_alive: bool = True,
     timeout: Optional[float] = None,
-    ssl_context: Optional[ssl.SSLContext] = None
+    ssl_context: Optional[ssl.SSLContext] = None,
+    source_address: Optional[str] = None,
+    source_port: int = 0
 ) -> socket.socket:
     family, connect = format_address(address, port)
     sock = _create_stream_sock(address, family, bind=False, reuse_address=reuse_address, ssl_context=ssl_context)
     _normalize_and_set_sock_timeout(sock, timeout)
 
     try:
+        if source_address:
+            _, bind = format_address(source_address, source_port)
+            sock.bind(bind)
         sock.connect(connect)
     except OSError as e:
         with contextlib.suppress(Exception):
@@ -318,6 +323,12 @@ def socket_wait_readable(sock: socket.socket, *, timeout: Optional[float] = None
 def get_socket_family_str(sock: socket.socket) -> str:
     return _FAMILY_TO_STR.get(sock.family, "Unknown")
 
+def get_socket_address(sock: socket.socket) -> Optional[str]:
+    try:
+        return sock.getsockname()[0]
+    except OSError:
+        return None
+
 def get_socket_port(sock: socket.socket) -> Optional[int]:
     try:
         return sock.getsockname()[1]
@@ -371,6 +382,10 @@ def close(self) -> None:
     def family_str(self) -> str:
         return get_socket_family_str(self.sock)
 
+    @property
+    def address(self) -> Optional[str]:
+        return get_socket_address(self.sock)
+
     @property
     def port(self) -> Optional[int]:
         return get_socket_port(self.sock)