[Unit]
Description=usb-moded USB gadget controller
DefaultDependencies=no
Wants=systemd-udev-settle.service
Requires=dbus.socket
After=local-fs.target dbus.socket systemd-udev-settle.service
Conflicts=shutdown.target

[Service]
Type=notify
TimeoutSec=25
EnvironmentFile=-/var/lib/environment/usb-moded/*.conf
EnvironmentFile=-/run/usb-moded/*.conf
ExecStart=/usr/sbin/usb_moded --systemd --force-syslog $USB_MODED_ARGS $USB_MODED_HW_ADAPTATION_ARGS
Restart=always
ExecReload=/bin/kill -HUP $MAINPID

## Sandboxing

# What we want to have is:
#
# /                  - readonly
# /tmp               - private writable
# /config            - shared writable (configfs gadget setup)
# /sys               - shared writable (android-usb gadget setup, wakelocks)
# /dev               - shared writable (mounting/unmounting mtp fs)
# /run/usb-moded     - shared writable (udhcpd config file)
# /var/lib/usb-moded - writable (usb-moded runtime settings data)
#
# Seems that attempting to use high level settings
# like ProtectSystem, PrivateTmp, ... leads to problems
# like mtp mount done from usb-moded not being visible
# to mtp daemon

ProtectSystem=no
PrivateDevices=no
PrivateTmp=no

# Could use low level settings, but they are not
# supported by our version of systemd ...

#ReadOnlyPaths=/
#ReadWritePaths=/tmp
#ReadWritePaths=/sys
#ReadWritePaths=/dev
#ReadWritePaths=/config
#ReadWritePaths=/run/usb-moded
#ReadWritePaths=/var/lib/usb-moded

# Usb-moded needs to start/stop user sessions services
# when activating/deactivating mtp mode -> must retain
# access to user data and home directories

ProtectHome=no

# a) The list of supplementary groups usb-moded needs to
#    function properly varies from one device to another.
# b) If any of the listed supplementary groups do not
#    exist on the system, systemd refuses to execute
#
# Combining (a) and (b) makes SupplementaryGroups useless,
# and we need to rely on CAP_DAC_OVERRIDE

#SupplementaryGroups=system wakelock ...

################################################################################################################################################################################################################################################################

## Security

# NoNewPrivileges does not work in Jolla Phone
#NoNewPrivileges=yes

# Note: Due to old systemd version: CapabilityBoundingSet merging
#       does not work - all caps must be listed on a single line.

# CAP_BLOCK_SUSPEND
# -> wakelocking

# CAP_NET_ADMIN
# CAP_NET_RAW
# -> network setup via ifconfig subprocess etc

# CAP_SETUID
# CAP_SETGID
# -> running systemctl-user -> uid/gid change

# CAP_SYS_RESOURCE
# -> running systemctl-user -> scheduling config

# CAP_DAC_OVERRIDE
# -> working around problems with SupplementaryGroups=

# CAP_SYS_ADMIN
# -> mount/unmount mtp device

CapabilityBoundingSet=CAP_BLOCK_SUSPEND CAP_NET_ADMIN CAP_NET_RAW CAP_SETUID CAP_SETGID CAP_SYS_RESOURCE CAP_DAC_OVERRIDE CAP_SYS_ADMIN

[Install]
WantedBy=basic.target