CTM(1) BSD General Commands Manual CTM(1)NAMEctm — source code mirror program
SYNOPSISctm [-cFklquv] [-b basedir] [-B backup-file] [-e include-regex]
[-t tar-command] [-T tmpdir] [-V level] [-x exclude-regex] file ...
DESCRIPTION
The ctm utility was originally “Cvs Through eMail”, but now instead it
seems more fitting to call it “Current Through eMail”.
The ctm utility is now meant to be the definitive way to make and apply a
delta between two versions of a directory tree.
There are two parts to this, making the delta and applying it. These are
two entirely different things.
Usage
To apply a CTM delta, you pass it to the ctm command. You can pass a CTM
delta on stdin, or you can give the filename as an argument. If you do
the latter, you make life a lot easier for your self, since the program
can accept gzip'ed files and since it will not have to make a temporary
copy of your file. You can specify multiple deltas at one time, they
will be processed one at a time. Deltas that are already applied will be
ignored.
The ctm command runs in a number of passes. It will process the entire
input file in each pass, before commencing with the next pass.
Before working on a file name ctm first checks for the existence of the
file name.ctm. If this file exists, ctm works on it instead.
Pass 1 will verify that the input file is OK. The syntax, the data and
the global MD5 checksum will be checked. If any of these fail, ctm will
simply reject the input file.
Pass 2 will validate that the directory tree is in the state expected by
the CTM delta. This is done by looking for files and directories which
should/should not exist and by checking the MD5 checksums of files.
If a backup-file had been specified using the -B option, all files that
would be modified by this ctm invocation are backed up to this file using
the archiver command specified by the -t option. The default archiver
command is tar -rf %s -T -.
Pass 3 will actually apply the delta.
The list of files that would be modified by ctm is subject to filtering
regular expressions specified using the -e and -x options. The -e and -x
options are applied in order of appearance on the command line. The last
filter that matched a given file name determines whether the file would
be operated on or left alone by ctm.
The ctm utility will extract the file hierarchy below its working direc‐
tory. Absolute filenames or filenames containing references through ‘.’
and ‘..’ are explicitly prohibited as a security measure.
Options
-b basedir
Prepend the path basedir to every filename.
-B backup-file
Backup all files that would be modified by this CTM run to
backup-file. If any filters are specified using the -e and -x
options, then the final set of files backed up are those that
would be modified by CTM after the filters are applied.
-c Check it out, do not do anything.
-e regular_expression
Match each name in the CTM file against regular_expression, and
if it matches process the file, otherwise leave it alone. There
may be any number of these options. Use of this option disables
the .ctm_status sequence number checks. For example, the expres‐
sion ^usr.sbin/ctm for example, will select the usr.sbin/ctm
source directory and all pathnames under it.
Pathnames can be disabled from being considered by CTM using the
-x option.
-F Force.
-k Keep files and directories and do not remove them even if the CTM
file specifies they are to be removed. If the -B option is spec‐
ified, these files and directories will not be backed up.
-l List files that would be modified by this invocation of CTM and
the actions that would be performed on them. Use of the -l
option disables the .ctm_status checks and integrity checks on
the source tree being operated on. The -l option can be combined
with the -e and -x options to determine which files would be mod‐
ified by the given set of command line options.
-q Tell us less.
-t tar-command
Use tar-command instead of the default archiver tar. This option
takes effect only if a backup file had been specified using the
-B option. A %s in the tar command will be replaced by the name
of the backup file.
-T tmpdir
Put temporary files under tmpdir.
-u Set modification time of created and modified files to the CTM
delta creation time.
-v Tell us more.
-V level
Tell us more. Level is the level of verbosity.
-x regular_expression
Match each name in the CTM file against regular_expression and if
it matches, leave the file alone. There may be any number of
these options. Use of this option disables the .ctm_status
sequence number checks.
Pathnames can be selected for CTM's consideration using the -e
option.
SECURITY
On its own, CTM is an insecure protocol - there is no authentication per‐
formed that the changes applied to the source code were sent by a trusted
party, and so care should be taken if the CTM deltas are obtained via an
unauthenticated medium such as regular email. It is a relatively simple
matter for an attacker to forge a CTM delta to replace or precede the
legitimate one and insert malicious code into your source tree. If the
legitimate delta is somehow prevented from arriving, this will go unno‐
ticed until a later delta attempts to touch the same file, at which point
the MD5 checksum will fail.
To remedy this insecurity, CTM pieces generated by FreeBSD.org are cryp‐
tographically signed in a format compatible with the GNU Privacy Guard
utility, available in /usr/ports/security/gpg, and the Pretty Good Pri‐
vacy v5 utility, /usr/ports/security/pgp5. The relevant public key can
be obtained by fingering ctm@FreeBSD.org.
CTM deltas which are thus signed cannot be undetectably altered by an
attacker. Therefore it is recommended that you make use of GPG or PGP5
to verify the signatures if you receive your CTM deltas via email.
ENVIRONMENT
TMPDIR, if set to a pathname, will cause ctm to use that pathname as the
location of temporary file. See tempnam(3), for more details on this.
The same effect may be achieved with the -T flag.
FILES
.ctm_status contains the sequence number of the last CTM delta applied.
Changing or removing this file will greatly confuse ctm.
Using the -e and -x options can update a partial subset of the source
tree and causes sources to be in an inconsistent state. It is assumed
that you know what you are doing when you use these options.
EXAMPLES
cd ~cvs
/usr/sbin/ctm ~ctm/cvs-*
To extract and patch all sources under `lib'
cd ~/lib-srcs
/usr/sbin/ctm -e '^lib' ~ctm/src-cur*
DIAGNOSTICS
Numerous messages, hopefully self-explanatory. The “noise level” can be
adjusted with the -q, -v and -V options.
SEE ALSOctm_rmail(1), ctm(5)HISTORY
Initial trials were run during the work on FreeBSD 1.1.5, and many bugs
and methods were hashed out.
The ctm command appeared in FreeBSD 2.1.
AUTHORS
The CTM system has been designed and implemented by Poul-Henning Kamp
⟨phk@FreeBSD.org⟩.
Joerg Wunsch ⟨joerg@FreeBSD.org⟩ wrote this man-page.
BSD March 25, 1995 BSD
