path: root/usr/src/man/man1m/lofiadm.1m

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.TH LOFIADM 1M "Aug 28, 2013"
.SH NAME
lofiadm \- administer files available as block devices through lofi
.SH SYNOPSIS
.LP
.nf
\fBlofiadm\fR [\fB-r\fR] \fB-a\fR \fIfile\fR [\fIdevice\fR]
.fi

.LP
.nf
\fBlofiadm\fR [\fB-r\fR] \fB-c\fR \fIcrypto_algorithm\fR \fB-a\fR \fIfile\fR [\fIdevice\fR]
.fi

.LP
.nf
\fBlofiadm\fR [\fB-r\fR] \fB-c\fR \fIcrypto_algorithm\fR \fB-k\fR \fIraw_key_file\fR \fB-a\fR \fIfile\fR [\fIdevice\fR]
.fi

.LP
.nf
\fBlofiadm\fR [\fB-r\fR] \fB-c\fR \fIcrypto_algorithm\fR \fB-T\fR \fItoken_key\fR \fB-a\fR \fIfile\fR [\fIdevice\fR]
.fi

.LP
.nf
\fBlofiadm\fR [\fB-r\fR] \fB-c\fR \fIcrypto_algorithm\fR \fB-T\fR \fItoken_key\fR
     \fB-k\fR \fIwrapped_key_file\fR \fB-a\fR \fIfile\fR [\fIdevice\fR]
.fi

.LP
.nf
\fBlofiadm\fR [\fB-r\fR] \fB-c\fR \fIcrypto_algorithm\fR \fB-e\fR \fB-a\fR \fIfile\fR [\fIdevice\fR]
.fi

.LP
.nf
\fBlofiadm\fR \fB-C\fR \fIalgorithm\fR [\fB-s\fR \fIsegment_size\fR] \fIfile\fR
.fi

.LP
.nf
\fBlofiadm\fR \fB-d\fR \fIfile\fR | \fIdevice\fR
.fi

.LP
.nf
\fBlofiadm\fR \fB-U\fR \fIfile\fR
.fi

.LP
.nf
\fBlofiadm\fR [ \fIfile\fR | \fIdevice\fR]
.fi

.SH DESCRIPTION
.sp
.LP
\fBlofiadm\fR administers \fBlofi\fR, the loopback file driver. \fBlofi\fR
allows a file to be associated with a block device. That file can then be
accessed through the block device. This is useful when the file contains an
image of some filesystem (such as a floppy or \fBCD-ROM\fR image), because the
block device can then be used with the normal system utilities for mounting,
checking or repairing filesystems. See \fBfsck\fR(1M) and \fBmount\fR(1M).
.sp
.LP
Use \fBlofiadm\fR to add a file as a loopback device, remove such an
association, or print information about the current associations.
.sp
.LP
Encryption and compression options are mutually exclusive on the command line.
Further, an encrypted file cannot be compressed later, nor can a compressed
file be encrypted later.
.sp
.LP
The \fBlofi\fR driver is not available and will not work inside a zone.
.SH OPTIONS
.sp
.LP
The following options are supported:
.sp
.ne 2
.na
\fB\fB-a\fR \fIfile\fR [\fIdevice\fR]\fR
.ad
.sp .6
.RS 4n
Add \fIfile\fR as a block device.
.sp
If \fIdevice\fR is not specified, an available device is picked.
.sp
If \fIdevice\fR is specified, \fBlofiadm\fR attempts to assign it to
\fIfile\fR. \fIdevice\fR must be available or \fBlofiadm\fR will fail. The
ability to specify a device is provided for use in scripts that wish to
reestablish a particular set of associations.
.RE

.sp
.ne 2
.na
\fB\fB-C\fR {\fIgzip\fR | \fIgzip-N\fR | \fIlzma\fR}\fR
.ad
.sp .6
.RS 4n
Compress the file with the specified compression algorithm.
.sp
The \fBgzip\fR compression algorithm uses the same compression as the
open-source \fBgzip\fR command. You can specify the \fBgzip\fR level by using
the value \fBgzip-\fR\fIN\fR where \fIN\fR is 6 (fast) or 9 (best compression
ratio). Currently, \fBgzip\fR, without a number, is equivalent to \fBgzip-6\fR
(which is also the default for the \fBgzip\fR command).
.sp
\fIlzma\fR stands for the LZMA (Lempel-Ziv-Markov) compression algorithm.
.sp
Note that you cannot write to a compressed file, nor can you mount a compressed
file read/write.
.RE

.sp
.ne 2
.na
\fB\fB-d\fR \fIfile\fR | \fIdevice\fR\fR
.ad
.sp .6
.RS 4n
Remove an association by \fIfile\fR or \fIdevice\fR name, if the associated
block device is not busy, and deallocates the block device.
.RE

.sp
.ne 2
.na
\fB\fB-r\fR
.ad
.sp .6
.RS 4n
If the \fB-r\fR option is specified before the \fB-a\fR option, the
\fIdevice\fR will be opened read-only.
.RE

.sp
.ne 2
.na
\fB\fB-s\fR \fIsegment_size\fR\fR
.ad
.sp .6
.RS 4n
The segment size to use to divide the file being compressed. \fIsegment_size\fR
can be an integer multiple of 512.
.RE

.sp
.ne 2
.na
\fB\fB-U\fR \fIfile\fR\fR
.ad
.sp .6
.RS 4n
Uncompress a compressed file.
.RE

.sp
.LP
The following options are used when the file is encrypted:
.sp
.ne 2
.na
\fB\fB-c\fR \fIcrypto_algorithm\fR\fR
.ad
.sp .6
.RS 4n
Select the encryption algorithm. The algorithm must be specified when
encryption is enabled because the algorithm is not stored in the disk image.
.sp
If none of \fB-e\fR, \fB-k\fR, or \fB-T\fR is specified, \fBlofiadm\fR prompts
for a passphrase, with a minimum length of eight characters, to be entered .
The passphrase is used to derive a symmetric encryption key using PKCS#5 PBKD2.
.RE

.sp
.ne 2
.na
\fB\fB-k\fR \fIraw_key_file\fR | \fIwrapped_key_file\fR\fR
.ad
.sp .6
.RS 4n
Path to raw or wrapped symmetric encryption key. If a PKCS#11 object is also
given with the \fB-T\fR option, then the key is wrapped by that object. If
\fB-T\fR is not specified, the key is used raw.
.RE

.sp
.ne 2
.na
\fB\fB-T\fR \fItoken_key\fR\fR
.ad
.sp .6
.RS 4n
The key in a PKCS#11 token to use for the encryption or for unwrapping the key
file.
.sp
If \fB-k\fR is also specified, \fB-T\fR identifies the unwrapping key, which
must be an RSA private key.
.RE

.sp
.ne 2
.na
\fB\fB-e\fR\fR
.ad
.sp .6
.RS 4n
Generate an ephemeral symmetric encryption key.
.RE

.SH OPERANDS
.sp
.LP
The following operands are supported:
.sp
.ne 2
.na
\fB\fIcrypto_algorithm\fR\fR
.ad
.sp .6
.RS 4n
One of: \fBaes-128-cbc\fR, \fBaes-192-cbc\fR, \fBaes-256-cbc\fR,
\fBdes3-cbc\fR, \fBblowfish-cbc\fR.
.RE

.sp
.ne 2
.na
\fB\fIdevice\fR\fR
.ad
.sp .6
.RS 4n
Display the file name associated with the block device \fIdevice\fR.
.sp
Without arguments, print a list of the current associations. Filenames must be
valid absolute pathnames.
.sp
When a file is added, it is opened for reading or writing by root. Any
restrictions apply (such as restricted root access over \fBNFS\fR). The file is
held open until the association is removed. It is not actually accessed until
the block device is used, so it will never be written to if the block device is
only opened read-only.
.RE

.sp
.ne 2
.na
\fB\fIfile\fR\fR
.ad
.sp .6
.RS 4n
Display the block device associated with \fIfile\fR.
.RE

.sp
.ne 2
.na
\fB\fIraw_key_file\fR\fR
.ad
.sp .6
.RS 4n
Path to a file of the appropriate length, in bits, to use as a raw symmetric
encryption key.
.RE

.sp
.ne 2
.na
\fB\fItoken_key\fR\fR
.ad
.sp .6
.RS 4n
PKCS#11 token object in the format:
.sp
.in +2
.nf
\fItoken_name\fR:\fImanufacturer_id\fR:\fIserial_number\fR:\fIkey_label\fR
.fi
.in -2
.sp

All but the key label are optional and can be empty. For example, to specify a
token object with only its key label \fBMylofiKey\fR, use:
.sp
.in +2
.nf
-T :::MylofiKey
.fi
.in -2
.sp

.RE

.sp
.ne 2
.na
\fB\fIwrapped_key_file\fR\fR
.ad
.sp .6
.RS 4n
Path to file containing a symmetric encryption key wrapped by the RSA private
key specified by \fB-T\fR.
.RE

.SH EXAMPLES
.LP
\fBExample 1 \fRMounting an Existing CD-ROM Image
.sp
.LP
You should ensure that Solaris understands the image before creating the
\fBCD\fR. \fBlofi\fR allows you to mount the image and see if it works.

.sp
.LP
This example mounts an existing \fBCD-ROM\fR image (\fBsparc.iso\fR), of the
\fBRed Hat 6.0 CD\fR which was downloaded from the Internet. It was created
with the \fBmkisofs\fR utility from the Internet.

.sp
.LP
Use \fBlofiadm\fR to attach a block device to it:

.sp
.in +2
.nf
# \fBlofiadm -a /home/mike_s/RH6.0/sparc.iso\fR
/dev/lofi/1
.fi
.in -2
.sp

.sp
.LP
\fBlofiadm\fR picks the device and prints the device name to the standard
output. You can run \fBlofiadm\fR again by issuing the following command:

.sp
.in +2
.nf
# \fBlofiadm\fR
Block Device     File                           Options
/dev/lofi/1      /home/mike_s/RH6.0/sparc.iso   -
.fi
.in -2
.sp

.sp
.LP
Or, you can give it one name and ask for the other, by issuing the following
command:

.sp
.in +2
.nf
# \fBlofiadm /dev/lofi/1\fR
/home/mike_s/RH6.0/sparc.iso
.fi
.in -2
.sp

.sp
.LP
Use the \fBmount\fR command to mount the image:

.sp
.in +2
.nf
# \fBmount -F hsfs -o ro /dev/lofi/1 /mnt\fR
.fi
.in -2
.sp

.sp
.LP
Check to ensure that Solaris understands the image:

.sp
.in +2
.nf
# \fBdf -k /mnt\fR
Filesystem            kbytes    used   avail capacity  Mounted on
/dev/lofi/1           512418  512418       0   100%    /mnt
# \fBls /mnt\fR
\&./            RedHat/       doc/          ls-lR         rr_moved/
\&../           TRANS.TBL     dosutils/     ls-lR.gz      sbin@
\&.buildlog     bin@          etc@          misc/         tmp/
COPYING       boot/         images/       mnt/          usr@
README        boot.cat*     kernels/      modules/
RPM-PGP-KEY   dev@          lib@          proc/
.fi
.in -2
.sp

.sp
.LP
Solaris can mount the CD-ROM image, and understand the filenames. The image was
created properly, and you can now create the \fBCD-ROM\fR with confidence.

.sp
.LP
As a final step, unmount and detach the images:

.sp
.in +2
.nf
# \fBumount /mnt\fR
# \fBlofiadm -d /dev/lofi/1\fR
# \fBlofiadm\fR
Block Device             File             Options
.fi
.in -2
.sp

.LP
\fBExample 2 \fRMounting a Floppy Image
.sp
.LP
This is similar to the first example.

.sp
.LP
Using \fBlofi\fR to help you mount files that contain floppy images is helpful
if a floppy disk contains a file that you need, but the machine which you are
on does not have a floppy drive. It is also helpful if you do not want to take
the time to use the \fBdd\fR command to copy the image to a floppy.

.sp
.LP
This is an example of getting to \fBMDB\fR floppy for Solaris on an x86
platform:

.sp
.in +2
.nf
# \fBlofiadm -a /export/s28/MDB_s28x_wos/latest/boot.3\fR
/dev/lofi/1
# \fBmount -F pcfs /dev/lofi/1 /mnt\fR
# \fBls /mnt\fR
\&./            COMMENT.BAT*  RC.D/         SOLARIS.MAP*
\&../           IDENT*        REPLACE.BAT*  X/
APPEND.BAT*   MAKEDIR.BAT*  SOLARIS/
# \fBumount /mnt\fR
# \fBlofiadm -d /export/s28/MDB_s28x_wos/latest/boot.3\fR
.fi
.in -2
.sp

.LP
\fBExample 3 \fRMaking a \fBUFS\fR Filesystem on a File
.sp
.LP
Making a \fBUFS\fR filesystem on a file can be useful, particularly if a test
suite requires a scratch filesystem. It can be painful (or annoying) to have to
repartition a disk just for the test suite, but you do not have to. You can
\fBnewfs\fR a file with \fBlofi\fR

.sp
.LP
Create the file:

.sp
.in +2
.nf
# \fBmkfile 35m /export/home/test\fR
.fi
.in -2
.sp

.sp
.LP
Attach it to a block device. You also get the character device that \fBnewfs\fR
requires, so \fBnewfs\fR that:

.sp
.in +2
.nf
# \fBlofiadm -a /export/home/test\fR
/dev/lofi/1
# \fBnewfs /dev/rlofi/1\fR
newfs: construct a new file system /dev/rlofi/1: (y/n)? \fBy\fR
/dev/rlofi/1:   71638 sectors in 119 cylinders of 1 tracks, 602 sectors
        35.0MB in 8 cyl groups (16 c/g, 4.70MB/g, 2240 i/g)
super-block backups (for fsck -F ufs -o b=#) at:
 32, 9664, 19296, 28928, 38560, 48192, 57824, 67456,
.fi
.in -2
.sp

.sp
.LP
Note that \fBufs\fR might not be able to use the entire file. Mount and use the
filesystem:

.sp
.in +2
.nf
# \fBmount /dev/lofi/1 /mnt\fR
# \fBdf -k /mnt\fR
Filesystem            kbytes    used   avail capacity  Mounted on
/dev/lofi/1            33455       9   30101     1%    /mnt
# \fBls /mnt\fR
\&./           ../          lost+found/
# \fBumount /mnt\fR
# \fBlofiadm -d /dev/lofi/1\fR
.fi
.in -2
.sp

.LP
\fBExample 4 \fRCreating a PC (FAT) File System on a Unix File
.sp
.LP
The following series of commands creates a \fBFAT\fR file system on a Unix
file. The file is associated with a block device created by \fBlofiadm\fR.

.sp
.in +2
.nf
# \fBmkfile 10M /export/test/testfs\fR
# \fBlofiadm -a /export/test testfs\fR
/dev/lofi/1
\fBNote use of\fR rlofi\fB, not\fR lofi\fB, in following command.\fR
# \fBmkfs -F pcfs -o nofdisk,size=20480 /dev/rlofi/1\fR
\fBConstruct a new FAT file system on /dev/rlofi/1: (y/n)?\fR y
# \fBmount -F pcfs /dev/lofi/1 /mnt\fR
# \fBcd /mnt\fR
# \fBdf -k .\fR
Filesystem            kbytes    used   avail capacity  Mounted on
/dev/lofi/1            10142       0   10142     0%    /mnt
.fi
.in -2
.sp

.LP
\fBExample 5 \fRCompressing an Existing CD-ROM Image
.sp
.LP
The following example illustrates compressing an existing CD-ROM image
(\fBsolaris.iso\fR), verifying that the image is compressed, and then
uncompressing it.

.sp
.in +2
.nf
# \fBlofiadm -C gzip /export/home/solaris.iso\fR
.fi
.in -2
.sp

.sp
.LP
Use \fBlofiadm\fR to attach a block device to it:

.sp
.in +2
.nf
# \fBlofiadm -a /export/home/solaris.iso\fR
  /dev/lofi/1
.fi
.in -2
.sp

.sp
.LP
Check if the mapped image is compressed:

.sp
.in +2
.nf
# \fBlofiadm\fR
Block Device      File                            Options
/dev/lofi/1       /export/home/solaris.iso        Compressed(gzip)
/dev/lofi/2       /export/home/regular.iso        -
.fi
.in -2
.sp

.sp
.LP
Unmap the compressed image and uncompress it:

.sp
.in +2
.nf
# \fBlofiadm -d /dev/lofi/1\fR
# \fBlofiadm -U /export/home/solaris.iso\fR
.fi
.in -2
.sp

.LP
\fBExample 6 \fRCreating an Encrypted UFS File System on a File
.sp
.LP
This example is similar to the example of making a UFS filesystem on a file,
above.

.sp
.LP
Create the file:

.sp
.in +2
.nf
# \fBmkfile 35m /export/home/test\fR
.fi
.in -2
.sp

.sp
.LP
Attach the file to a block device and specify that the file image is encrypted.
As a result of this command, you obtain the character device, which is
subsequently used by \fBnewfs\fR:

.sp
.in +2
.nf
# \fBlofiadm -c aes-256-cbc -a /export/home/secrets\fR
Enter passphrase: \fBMy-M0th3r;l0v3s_m3+4lw4ys!\fR           (\fBnot echoed\fR)
Re-enter passphrase: \fBMy-M0th3r;l0v3s_m3+4lw4ys!\fR        (\fBnot echoed\fR)
/dev/lofi/1

# \fBnewfs /dev/rlofi/1\fR
newfs: construct a new file system /dev/rlofi/1: (y/n)? \fBy\fR
/dev/rlofi/1:   71638 sectors in 119 cylinders of 1 tracks, 602 sectors
       35.0MB in 8 cyl groups (16 c/g, 4.70MB/g, 2240 i/g)
super-block backups (for fsck -F ufs -o b=#) at:
32, 9664, 19296, 28928, 38560, 48192, 57824, 67456,
.fi
.in -2
.sp

.sp
.LP
The mapped file system shows that encryption is enabled:

.sp
.in +2
.nf
# \fBlofiadm\fR
Block Device    File                     Options
/dev/lofi/1     /export/home/secrets     Encrypted
.fi
.in -2
.sp

.sp
.LP
Mount and use the filesystem:

.sp
.in +2
.nf
# \fBmount /dev/lofi/1 /mnt\fR
# \fBcp moms_secret_*_recipe /mnt\fR
# \fBls /mnt\fR
\&./           moms_secret_cookie_recipe    moms_secret_soup_recipe
\&../          moms_secret_fudge_recipe     moms_secret_stuffing_recipe
lost+found/  moms_secret_meatloaf_recipe  moms_secret_waffle_recipe
# \fBumount /mnt\fR
# \fBlofiadm -d /dev/lofi/1\fR
.fi
.in -2
.sp

.sp
.LP
Subsequent attempts to map the filesystem with the wrong key or the wrong
encryption algorithm will fail:

.sp
.in +2
.nf
# \fBlofiadm -c blowfish-cbc -a /export/home/secrets\fR
Enter passphrase: \fBmommy\fR                                (\fInot echoed\fR)
Re-enter passphrase: \fBmommy\fR                             (\fInot echoed\fR)
lofiadm: could not map file /root/lofi: Invalid argument
# \fBlofiadm\fR
Block Device    File                    Options
#
.fi
.in -2
.sp

.sp
.LP
Attempts to map the filesystem without encryption will succeed, however
attempts to mount and use the filesystem will fail:

.sp
.in +2
.nf
# \fBlofiadm -a /export/home/secrets\fR
/dev/lofi/1
# \fBlofiadm\fR
Block Device    File                     Options
/dev/lofi/1     /export/home/secrets     -
# \fBmount /dev/lofi/1 /mnt\fR
mount: /dev/lofi/1 is not this fstype
#
.fi
.in -2
.sp

.SH ENVIRONMENT VARIABLES
.sp
.LP
See \fBenviron\fR(5) for descriptions of the following environment variables
that affect the execution of \fBlofiadm\fR: \fBLC_CTYPE\fR, \fBLC_MESSAGES\fR
and \fBNLSPATH\fR.
.SH EXIT STATUS
.sp
.LP
The following exit values are returned:
.sp
.ne 2
.na
\fB\fB0\fR\fR
.ad
.sp .6
.RS 4n
Successful completion.
.RE

.sp
.ne 2
.na
\fB\fB>0\fR\fR
.ad
.sp .6
.RS 4n
An error occurred.
.RE

.SH SEE ALSO
.sp
.LP
\fBfsck\fR(1M), \fBmount\fR(1M), \fBmount_ufs\fR(1M), \fBnewfs\fR(1M),
\fBattributes\fR(5), \fBlofi\fR(7D), \fBlofs\fR(7FS)
.SH NOTES
.sp
.LP
Just as you would not directly access a disk device that has mounted file
systems, you should not access a file associated with a block device except
through the \fBlofi\fR file driver. It might also be appropriate to ensure that
the file has appropriate permissions to prevent such access.
.sp
.LP
The abilities of \fBlofiadm\fR, and who can use them, are controlled by the
permissions of \fB/dev/lofictl\fR. Read-access allows query operations, such as
listing all the associations. Write-access is required to do any state-changing
operations, like adding an association. As shipped, \fB/dev/lofictl\fR is owned
by \fBroot\fR, in group \fBsys\fR, and mode \fB0644\fR, so all users can do
query operations but only root can change anything. The administrator can give
users write-access, allowing them to add or delete associations, but that is
very likely a security hole and should probably only be given to a trusted
group.
.sp
.LP
When mounting a filesystem image, take care to use appropriate mount options.
In particular, the \fBnosuid\fR mount option might be appropriate for \fBUFS\fR
images whose origin is unknown. Also, some options might not be useful or
appropriate, like \fBlogging\fR or \fBforcedirectio\fR for \fBUFS\fR. For
compatibility purposes, a raw device is also exported along with the block
device. For example, \fBnewfs\fR(1M) requires one.
.sp
.LP
The output of \fBlofiadm\fR (without arguments) might change in future
releases.