otg msd helpers

6 files changed, 166 insertions, 0 deletions

diff --git a/kvmd/helpers/__init__.py b/kvmd/helpers/__init__.py
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/kvmd/helpers/__init__.py
diff --git a/kvmd/helpers/otgmsd/__init__.py b/kvmd/helpers/otgmsd/__init__.py
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/kvmd/helpers/otgmsd/__init__.py
diff --git a/kvmd/helpers/otgmsd/remount/__init__.py b/kvmd/helpers/otgmsd/remount/__init__.py
new file mode 100644
index 00000000..2eba6add
--- /dev/null
+++ b/kvmd/helpers/otgmsd/remount/__init__.py
@@ -0,0 +1,64 @@
+# ========================================================================== #
+#                                                                            #
+#    KVMD - The main Pi-KVM daemon.                                          #
+#                                                                            #
+#    Copyright (C) 2018  Maxim Devaev <[email protected]>                    #
+#                                                                            #
+#    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/>.  #
+#                                                                            #
+# ========================================================================== #
+
+
+import sys
+import subprocess
+
+
+# ====
+_MOUNT_PATH = "/bin/mount"
+_FSTAB_PATH = "/etc/fstab"
+_OPTION = "X-kvmd.otg-msd"
+
+
+# =====
+def _find_mountpoint() -> str:
+    with open(_FSTAB_PATH) as fstab_file:
+        for line in fstab_file.read().split("\n"):
+            line = line.strip()
+            if line and not line.startswith("#"):
+                parts = line.split()
+                if len(parts) == 6:
+                    options = parts[3].split(",")
+                    if _OPTION in options:
+                        return parts[1]
+    raise SystemExit(f"Can't find {_OPTION!r} mountpoint in {_FSTAB_PATH}")
+
+
+def _remount(path: str, ro: bool) -> None:
+    try:
+        subprocess.check_call([
+            _MOUNT_PATH,
+            "--options",
+            f"remount,{'ro' if ro else 'rw'}",
+            path,
+        ])
+    except subprocess.CalledProcessError as err:
+        raise SystemExit(str(err)) from None
+
+
+# =====
+def main() -> None:
+    if len(sys.argv) != 2 or sys.argv[1] not in ["ro", "rw"]:
+        raise SystemExit(f"This program will remount a first volume marked by {_OPTION!r} option in {_FSTAB_PATH}\n\n"
+                         f"Usage: python -m kvmd.helpers.otgmsd.remount [-h|--help|ro|rw]")
+    _remount(_find_mountpoint(), (sys.argv[1] == "ro"))
diff --git a/kvmd/helpers/otgmsd/remount/__main__.py b/kvmd/helpers/otgmsd/remount/__main__.py
new file mode 100644
index 00000000..77f4e294
--- /dev/null
+++ b/kvmd/helpers/otgmsd/remount/__main__.py
@@ -0,0 +1,24 @@
+# ========================================================================== #
+#                                                                            #
+#    KVMD - The main Pi-KVM daemon.                                          #
+#                                                                            #
+#    Copyright (C) 2018  Maxim Devaev <[email protected]>                    #
+#                                                                            #
+#    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 . import main
+main()
diff --git a/kvmd/helpers/otgmsd/unlock/__init__.py b/kvmd/helpers/otgmsd/unlock/__init__.py
new file mode 100644
index 00000000..9bdf353f
--- /dev/null
+++ b/kvmd/helpers/otgmsd/unlock/__init__.py
@@ -0,0 +1,54 @@
+# ========================================================================== #
+#                                                                            #
+#    KVMD - The main Pi-KVM daemon.                                          #
+#                                                                            #
+#    Copyright (C) 2018  Maxim Devaev <[email protected]>                    #
+#                                                                            #
+#    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/>.  #
+#                                                                            #
+# ========================================================================== #
+
+
+import sys
+import signal
+
+import psutil
+
+
+# =====
+_PROCESS_NAME = "file-storage"
+
+
+# =====
+def _unlock() -> None:
+    # https://github.com/torvalds/linux/blob/3039fad/drivers/usb/gadget/function/f_mass_storage.c#L2924
+    found = False
+    for proc in psutil.process_iter():
+        attrs = proc.as_dict(attrs=["name", "exe"])
+        if attrs.get("name") == _PROCESS_NAME and not attrs.get("exe"):
+            try:
+                proc.send_signal(signal.SIGUSR1)
+                found = True
+            except Exception as err:
+                raise SystemExit(f"Can't send SIGUSR1 to MSD kernel thread with pid={attrs['pid']}: {err}")
+    if not found:
+        raise SystemExit(f"Can't find MSD kernel thread {_PROCESS_NAME!r}")
+
+
+# =====
+def main() -> None:
+    if len(sys.argv) != 2 or sys.argv[1] != "unlock":
+        raise SystemExit(f"This program interrupts all IO operations performed by OTG MSD.\n\n"
+                         f"Usage: python -m kvmd.helpers.otgmsd.unlock [-h|--help|unlock]")
+    _unlock()
diff --git a/kvmd/helpers/otgmsd/unlock/__main__.py b/kvmd/helpers/otgmsd/unlock/__main__.py
new file mode 100644
index 00000000..77f4e294
--- /dev/null
+++ b/kvmd/helpers/otgmsd/unlock/__main__.py
@@ -0,0 +1,24 @@
+# ========================================================================== #
+#                                                                            #
+#    KVMD - The main Pi-KVM daemon.                                          #
+#                                                                            #
+#    Copyright (C) 2018  Maxim Devaev <[email protected]>                    #
+#                                                                            #
+#    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 . import main
+main()