The utility
mtree
compares the file hierarchy rooted in the current directory against a
specification read from the standard input.
Messages are written to the standard output for any files whose
characteristics do not match the specification, or which are
missing from either the file hierarchy or the specification.
The options are as follows:
-c
Print a specification for the file hierarchy to the standard output.
-d
Ignore everything except directory type files.
-e
Don't complain about files that are in the file hierarchy, but not in the
specification.
-f spec
Read the specification from file
spec
instead of from the standard input.
-i
Indents the output 4 spaces each time a directory level is descended when
create a specification with the
-c
option.
This does not effect either the /set statements or the comment before each
directory.
It does however effect the comment before the close of each directory.
-K keywords
Add the specified (whitespace or comma separated) keywords to the current
set of keywords.
-k keywords
Use the
``type''
keyword plus the specified (whitespace or comma separated)
keywords instead of the current set of keywords.
-n
Do not emit pathname comments when creating a specification.
Normally
a comment is emitted before each directory and before the close of that
directory when using the
-c
option.
-p path
Use the file hierarchy rooted in
path
instead of the current directory.
-q
Quiet mode.
Do not complain when a
``missing''
directory can not be created because it is already exists.
This occurs when the directory is a symbolic link.
-r
Remove any files in the file hierarchy that are not described in the
specification.
-s seed
Display a single checksum to the standard error output that represents all
of the files for which the keyword
cksum
was specified.
The checksum is seeded with the specified value.
-t
If a file's timestamp is different from the specification,
``touch''
it to match the specification (and list as modified).
-U
Modify the owner, group, and permissions of existing files to match
the specification and create any missing directories.
User, group, and permissions must all be specified for missing directories
to be created.
Exit with a status of 0 on success, 1 if any error occurred,
a mismatch is not considered an error if it was corrected.
-u
Same as the
-U
option except a status of 2 is returned if the file hierarchy
did not match the specification.
-x
Don't descend below mount points in the file hierarchy.
Specifications are mostly composed of
``keywords''
(i.e., strings that specify values relating to files).
No keywords have default values, and if a keyword has no value set, no
checks based on it are performed.
Currently supported keywords are as follows:
cksum
The checksum of the file using the default algorithm specified by
the
cksum(1)
utility.
ignore
Ignore any file hierarchy below this file.
gid
The file group as a numeric value.
gname
The file group as a symbolic name.
md5digest
The MD5 message digest of the file.
mode
The current file's permissions as a numeric (octal) or symbolic
value.
nlink
The number of hard links the file is expected to have.
optional
The file is optional; don't complain about the file if it's
not in the file hierarchy.
rmd160digest
The RIPEMD-160 message digest of the file.
sha1digest
The SHA-1 message digest of the file.
uid
The file owner as a numeric value.
uname
The file owner as a symbolic name.
size
The size, in bytes, of the file.
link
The file the symbolic link is expected to reference.
time
The last modification time of the file.
type
The type of the file; may be set to any one of the following:
block
block special device
char
character special device
dir
directory
fifo
fifo
file
regular file
link
symbolic link
socket
socket
The default set of keywords are
gidmodenlinksizelinktime
and
uid
There are four types of lines in a specification.
The first type of line sets a global value for a keyword, and consists of
the string
``/set''
followed by whitespace, followed by sets of keyword/value
pairs, separated by whitespace.
Keyword/value pairs consist of a keyword, followed by an equals sign
(`='
)
followed by a value, without whitespace characters.
Once a keyword has been set, its value remains unchanged until either
reset or unset.
The second type of line unsets keywords and consists of the string
``/unset''
followed by whitespace, followed by one or more keywords,
separated by whitespace.
The third type of line is a file specification and consists of a file
name, followed by whitespace, followed by zero or more whitespace
separated keyword/value pairs.
The file name may be preceded by whitespace characters.
The file name may contain any of the standard file name matching
characters
Po ``[''
``]''
``?''
or
``*''
Pc ,
in which case files in the hierarchy will be associated with the first
pattern that they match.
Each of the keyword/value pairs consist of a keyword, followed by an
equals sign, followed by the keyword's value, without
whitespace characters.
These values override, without changing, the global value of the
corresponding keyword.
All paths are relative.
Specifying a directory will cause subsequent files to be searched
for in that directory hierarchy.
Which brings us to the last type of line in a specification: a line
containing only the string
``..
''
causes the current directory
path to ascend one level.
Empty lines and lines whose first non-whitespace character is a hash
mark
(`#'
)
are ignored.
The
mtree
utility exits with a status of 0 on success, 1 if any error occurred,
and 2 if the file hierarchy did not match the specification.
A status of 2 is converted to a status of 0 if the
-U
option is used.
EXAMPLES
To detect system binaries that have been
``trojan horsed''
it is recommended
that
mtree
-Ksha1digest
be run on the file systems, and a copy of the results stored on a different
machine, or, at least, in encrypted form.
The output file itself should be digested using
openssldgst
-sha1
Then, periodically,
mtree
and
openssldgst
-sha1
should be run against the on-line specifications.
While it is possible for the bad guys to change the on-line specifications
to conform to their modified binaries, it is believed to be
impractical for them to create a modified specification which has
the same SHA1 digest as the original.
The
-d
and
-u
options can be used in combination to create directory hierarchies
for distributions and other such things; the files in
/etc/mtree
were used to create almost all directories in a normal binary
distribution.
