ClamAV(3)

NAME
Mail::ClamAV - Perl extension for the clamav virus scanner

SYNOPSIS
    use Mail::ClamAV qw/:all/;

    # $Mail::ClamAV::Error in numeric context return clamav's
    # error status code which corresponds to the constants which
    # can be exported
    my $c = new Mail::ClamAV("/path/to/directory/or/file")
        or die "Failed to load db: $Mail::ClamAV::Error (", 0+$Mail::;

    # You can get retdbdir() to get the database dir in
    # clamav's conf
    my $c = new Mail::ClamAV(retdbdir())
        or die "Failed to load db: $Mail::ClamAV::Error";

    # When database is loaded, you must create the proper trie with:
    $c->build or die "Failed to build engine: $Mail::ClamAV::Error";

    # check to see if we need to reload
    if ($c->statchkdir) {
        $c = new Mail::ClamAV(retdbdir());
        $c->build or die "Failed to build engine: $Mail::ClamAV::Error";
    }

    # Set some limits (only applies to scan())
    $c->maxreclevel(4);
    $c->maxfiles(20);
    $c->maxfilesize(1024 * 1024 * 20); # 20 megs

    # Scan a filehandle (scandesc in clamav)
    # scan(FileHandle or path, Bitfield of options)
    my $status = $c->scan(FH, CL_SCAN_ARCHIVE|CL_SCAN_MAIL);

    # Scan a file (scanfile in clamav)
    my $status = $c->scan("/path/to/file.eml", CL_SCAN_MAIL);

    # $status is an overloaded object
    die "Failed to scan: $status" unless $status;
    if ($status->virus) {
        print "Message is a virus: $status\n";
    }
    else {
        print "No virus found!\n";
    }

DESCRIPTION
Clam AntiVirus is an anti-virus toolkit for UNIX <http://www.clamav.com/>. This module provide a simple interface to its C API.

  EXPORT
None by default.

  Exportable constants
Options for scanning.

CL_SCAN_STDOPT
    This is an alias for a recommended set of scan options. You should use it to make your software ready for new features in the future versions of libclamav.

CL_SCAN_RAW
    Use it alone if you want to disable support for special files.

CL_SCAN_ARCHIVE
    This flag enables transparent scanning of various archive formats.

CL_SCAN_BLOCKENCRYPTED
    With this flag the library will mark encrypted archives as viruses (Encrypted.Zip, Encrypted.RAR).

CL_SCAN_BLOCKMAX
    Mark archives as viruses if maxfiles, maxfilesize, or maxreclevel limit is reached.

CL_SCAN_MAIL
    Enable support for mail files.

CL_SCAN_MAILURL
    The mail scanner will download and scan URLs listed in a mail body. This flag should not be used on loaded servers. Due to potential problems please do not enable it by default but make it optional.

CL_SCAN_OLE2
    Enables support for OLE2 containers (used by MS Office and .msi files).

CL_SCAN_PE
    This flag enables deep scanning of Portable Executable files and allows libclamav to unpack executables compressed with run-time unpackers.

CL_SCAN_ELF
    Enable support for ELF files.

CL_SCAN_BLOCKBROKEN
    libclamav will try to detect broken executables and mark them as Broken.Executable.

CL_SCAN_HTML
    This flag enables HTML normalisation (including ScrEnc decryption).

CL_SCAN_ALGORITHMIC
    Enable algorithmic detection of viruses.

CL_SCAN_PHISHING_DOMAINLIST
    With a minor version bump clamav development team removed this and broke backwards compatibility, so it is no longer supported in this module as of 0.22.

CL_SCAN_PHISHING_BLOCKSSL
    Phishing module: always block SSL mismatches in URLs.

CL_SCAN_PHISHING_BLOCKCLOAK
    Phishing module: always block cloaked URLs.

Status returns. You can get the status code by putting the status object returned into into numeric context.

    my $status = $c->scan("foo.txt");
    print "Status: ", ($status + 0), "\n";

The following are returned statuses if no error occured.

CL_CLEAN
    no viruses found

CL_VIRUS
    virus found, put the status in scalar context to see the type

Error statuses

CL_EMAXREC
    recursion limit exceeded

CL_EMAXSIZE
    size limit exceeded

CL_EMAXFILES
    files limit exceeded

CL_EACCES
    access denied

CL_ENULLARG
    null argument

CL_ETMPFILE
    tmpfile() failed

CL_EMEM
    memory allocation error

CL_EOPEN
    file open error

CL_EMALFDB
    malformed database

CL_ETMPDIR
    mkdir() failed

CL_ECVD
    not a CVD file (or broken)

CL_EFORMAT
    bad format or broken file

CL_ENCINIT
    NodalCore initialization failed

CL_ENCLOAD
    error loading NodalCore database

CL_ENCIO
    general NodalCore I/O error

  Exportable functions
These function can be exported either individually or using the :all export flags

retdbdir
    This function returns the path to the database directory specified when clamav was compiled.

METHODS

  Settings
NOTE These settings only apply to "scan()" and archives (CL_SCAN_ARCHIVE).

maxreclevel
    Sets the maximum recursion level into archives [default 5].

maxmailrec
    With a minor version bump clamav development team removed this and broke backwards compatibility, so it is no longer supported in this module as of 0.22.

maxfiles
    Maximum number of files that will be scanned [default 1000]. A value of zero disables the check.

maxfilesize
    Maximum file size that will be scanned in bytes [default 10M]. A value of zero disables the check.

maxratio
    With a minor version bump clamav development team removed this and broke backwards compatibility, so it is no longer supported in this module as of 0.22.

  Scanning
All of these methods return a status object. This object is overloaded to make things cleaner. In boolean context this will return false if there was an error. For example:
    my $status = $c->scan("foo.txt");
    die "Error scanning: $status" unless $status;

As you probably just noticed, $status in scalar context returns the error message. In addition to the overloading you just saw, $status has the following methods:

errno
    The numeric value (if any) clamav returned.

clean
    This will be true if the message was not a virus and an error did not occur.

virus
    Returns true if the message is a virus.

error
    Return the error message (if any). This is the same thing as quoting $status.

count
    Returns the number of messages scanned. Only works with archives.

scan(FileHandle or Path, Bitfield of options)
    "scan()" takes a FileHanle or path and passed the file descriptor for that off to clamav. The second argument is a bitfield of options, CL_SCAN_MAIL, CL_SCAN_ARCHIVE or CL_SCAN_RAW "Exportable constants".

    This function returns the status object discussed earlier.

    Note that if you are running in taint mode (-T) and a tainted path is passed to "scan()", it will "croak()".

scanbuff($buff)
    This function was taken out of ClamAV in 0.90 and was thus taken out of Mail::ClamAV.

  Data Directory stats
If the path passed into "new()" is a directory Mail::ClamAV will set things up to check for updated database files. Calling the "statchkdir()" will check the database directory to the stats we have in memory. If anything has changed true is returned, otherwise false.

NOTE: trying to use "statchkdir()" when you passed in a database file instead of directory will produce a fatal error.

"statchkdir()" is useful for long running daemons that need to check to see if it is time to reload the database. Reloading is simply getting a new Mail::ClamAV object and initializing it.

SEE ALSO
The ClamAV API documentation <http://www.clamav.net/doc/html-0.65/node44.html>

AUTHOR
David P.C. Wollmann <converter42@gmail.com>

COPYRIGHT AND LICENSE
Copyright (C) 2003 by Gossamer Threads Inc. <http://www.gossamer-threads.com>

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.1 or, at your option, any later version of Perl 5 you may have available.