DSBMD is a media/filesystem type detecting daemon for FreeBSD that allows clients to mount storage devices. It is configured to work out of the box.
DSBMD watches the mount table for changes, monitors devd(8) events for new storage devices, polls CD/DVD drives and card readers for media change events, determines media types, volume names, and filesystem types. Mountable devices, changes in the mount table as well as device add/remove events and altered states of mountable devices are presented to clients. Clients can request DSBMD to mount, unmount, and eject media, or set the CD/DVD reading speed.
Some features are:
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Client authentication is handled using UNIX domain-socket credentials. Authorization can be defined on a user and/or group basis.
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For each supported filesystem, mount flags or external mount commands can be defined.
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Supported filesystems are: ISO-9660, FAT, NTFS, UFS, Ext2/3, Ext4, HFS+, exFAT, XFS, and Btrfs.
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Mounts and unmounts not initiated though DSBMD are detected, and necessary action are taken.
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Simple plain text protocol. DSBMD can be used and debugged using Telnet (telnet -u /var/run/dsbmd.socket) or Netcat (nc -U /var/run/dsbmd.socket).
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Easy configuration through /usr/local/etc/dsbmd.conf
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Support for FUSE
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Support for memory disks (md)
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Support for Linux LVM logical volumes through geom_linux_lvm(4)
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Support for MTP devices
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Support for PTP devices
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Support for NVD devices
-f
Run DSBMD in foreground.
# git clone https://github.com/mrclksr/DSBMD.git
# git clone https://github.com/mrclksr/dsbcfg.git
# cd DSBMD && make install
Running DSBMD together with hald is not recommended. Since both daemons access the same system resources and execute similar actions, this might lead to malfunction.
In order to start DSBMD at boot time, add the following line to your /etc/rc.conf:
dsbmd_enable="YES"
Depending on your needs, install the FreeBSD ports fusefs-exfat, fusefs-gphotofs, fusefs-ntfs, fusefs-ext2 (Ext2/3/4), fusefs-hfsfuse, fusefs-lkl (BTRFS, Ext4, and XFS), and fusefs-jmtpfs. DSBMD comes with predefined commands in dsbmd.conf that use these ports to mount the corresponding filesystems.
For further configuration, see dsbmd.conf.
If you want DSBMD to mount storage devices as regular user who initiated the mount command, set
usermount = true
in dsbmd.conf, and set the sysctl variable vfs.usermount to 1:
sysctl vfs.usermount=1
To make this setting permanent, add
vfs.usermount=1
to /etc/sysctl.conf
Configure DSBMD for mounting as regular user (see above). This will allow you to unmount automounted media without special privileges. Install sysutils/dsbmc-cli and start
dsbmc-cli -a
manually as regular user, or add the command
dsbmc-cli -a&
to your shell's rc file, or to your window manager's autostart file.
DSBMD operates on device nodes like da*, ada*, etc. If GEOM withering is enabled, and a device is mounted by its disk ID, all device nodes of that disk disappear in favour of its disk IDs under /dev/diskid. To disable this behavior, set
kern.geom.label.disk_ident.enable="0"
in /boot/loader.conf.
/var/run/dsbmd.socket
UNIX domain socket
/usr/local/etc/dsbmd.conf
Configuration file
/var/log/dsbmd.log
Logfile
If a client WITHOUT permission connects,
DSBMD
sends an error message with code
ERR_PERMISSION_DENIED (258),
and terminates the connection.
If a client WITH permission connects, DSBMD sends a list of zero or more devices using device add messages (2.5.1). The list is terminated by sending a '=' on a line by itself.
command [option [arg]] [option [arg]] ... <newline>
DSBMD sends a reply message for any sent known or unknown command. Between the transmission of the command and the reception of the command reply message, multiple information and/or device add/remove messages (2.1) can occur.
DSBMD processes each client's commands synchronously, that is, the commands will be processed in the same order as they where received. After a command's reply message was sent, the next command will be processed. DSBMD supports the following commands:
mount <device name>
Mount the given device.
unmount [-f] <device name>
If the -f switch is specified, unmounting will be enforced.
eject [-f] <device name>
This command unmounts and ejects the inserted media. If the -f switch is specified, unmounting and ejecting of the media will be enforced.
speed <device name> <speed>
Sets the maximum reading speed of the CD/DVD device.
size <device name>
This command asks DSBMD for the capacity of a disk. DSBMD will return the total size in bytes, and if the device is mounted, it will also return the number of used and free bytes.
mdattach </path/to/image>
Create a memory disk to access the given disk image.
<message type>:<keyword>=<value>:...:<keyword>=<value><newline>
*Message type* *Meaning*
+ A device/media was added
- A device/media was removed
M A device/media was mounted
U A device/media was unmounted
V The reading speed of a CD/DVD was changed.
E Command failed.
O Command execution was successful.
S Shutdown
*Keyword* *Value*
command mount, unmount, speed, eject, size
code errno number (< 257) or a special error code (>= 257)
dev Device name
mntpt Mount point
speed Max. CD/DVD reading speed.
mediasize Total capacity in bytes of a media
used Number of used bytes of a media
free Number of free bytes of a media
type Device/media type: HDD, AUDIOCD, DVD, VCD, USBDISK, SVCD,
DATACD, MMC, MTP, PTP
cmds A comma (',')
separated list of supported device commands.
mntcmderr Numerical return value of external mount command.
*Code* *Meaning*
257 Device already mounted
258 Permission denied
259 Device not mounted
260 Device busy
261 No such device
262 Max. number of connections reached
263 Not ejectable
264 Unknown command
265 Unknown option
266 Syntax error
267 No media
268 Unknown filesystem
269 Unknown error
270 Mount command failed
271 Invalid Argument
272 Command string too long
273 Invalid command string
274 Timeout
275 Not a regular file
+:dev=<devname>:type=<devtype>:cmds=<command list>
[:volid=<volid>][:mntpt=<mounted on>][:speed=<speed>]
-:dev=<devname>
If the speed of a CDROM device was changed, the following message will be sent to all connected clients, except for the client who sent the command.
V:dev=<devname>:speed=<speed>
If a device was mounted, the following message will be sent to all connected clients, exept for the client who sent the command.
M:dev=<devname>:mntpt=<mounted on>
If a device was unmounted, the following message will be sent to all connected clients, except for the client who sent the command.
U:dev=<devname>:mntpt=<mounted on>
If the daemon was terminated, it sends the following message to all connected clients:
S
E:code=<error code>[:command=<executed command>]
O:command=<executed command>[:keyword=value] ...
If a device was successfully mounted, DSBMD replies with the following message:
O:command=mount:dev=<devname>:mntpt=<mounted on>
If a device was successfully unmounted, DSBMD replies with the following message:
O:command=unmount:dev=<devname>:mntpt=<mounted on>
If the capacity of a disk device was requested, DSBMD sends the following message:
O:command=size:dev=<devname>:mediasize=<size>:used=<used>:free=<free>
Where 'size' is the storage capacity in bytes, 'used' is the number of used and 'free' is the number of free bytes. If the device/media is not mounted, 'free' and 'used' are 0.
- September 18, 2020