NAME
clamav-milter.conf - Configuration file for clamav-milter
DESCRIPTION
clamav-milter.conf contains the configuration options for clamav-
milter(8).
FILE FORMAT
The file consists of comments and options with arguments. Each line
which starts with a hash (#) symbol is ignored by the parser. Options
and arguments are case sensitive and of the form Option Argument. The
arguments are of the following types:
BOOL Boolean value (yes/no or true/false or 1/0).
STRING String without blank characters.
SIZE Size in bytes. You can use 'M' or 'm' modifiers for megabytes
and 'K' or 'k' for kilobytes.
NUMBER Unsigned integer.
MAIN OPTIONS
Example
If this option is set clamav-milter will not run.
MilterSocket STRING
Define the interface through which we communicate with sendmail.
This option is mandatory!
Possible formats are:
[[unix|local]:]/path/to/file - to specify a unix domain socket
inet:port@[hostname|ip-address] - to specify an ipv4 socket
inet6:port@[hostname|ip-address] - to specify an ipv6 socket
Default: unset
MilterSocketGroup STRING
Define the group ownership for the (unix) milter socket.
Default: disabled (the primary group of the user running clamd)
MilterSocketMode STRING
Sets the permissions on the (unix) milter socket to the
specified mode.
Default: disabled (obey umask)
FixStaleSocket BOOL
Remove stale socket after unclean shutdown.
Default: yes
User STRING
Run as another user (clamav-milter must be started by root for
this option to work)
Default: unset (don't drop privileges)
AllowSupplementaryGroups BOOL
Initialize supplementary group access (clamav-milter must be
started by root).
Default: no
ReadTimeout NUMBER
Waiting for data from clamd will timeout after this time
(seconds).
Default: 120
Foreground BOOL
Don't fork into background.
Default: no
Chroot STRING
Chroot to the specified directory. Chrooting is performed just
after reading the config file and before dropping privileges.
Default: unset (don't chroot)
PidFile STRING
Save the process identifier of a clamav-milter (main thread) to
a specified file.
Default: disabled
TemporaryDirectory STRING
Optional path to the global temporary directory.
Default: system specific (usually /tmp or /var/tmp).
CLAMD OPTIONS
ClamdSocket STRING
Define the clamd socket to connect to for scanning. This option
is mandatory! Syntax:
ClamdSocket unix:path
ClamdSocket tcp:host:port
The first syntax specifies a local unix socket (needs an
absolute path) e.g.:
ClamdSocket unix:/var/run/clamd/clamd.socket
The second syntax specifies a tcp local or remote tcp socket:
the host can be a hostname or an ip address; the ":port" field
is only required for IPv6 addresses, otherwise it defaults to
3310 e.g.:
ClamdSocket tcp:192.168.0.1
This option can be repeated several times with different sockets
or even with the same socket: clamd servers will be selected in
a round-robin fashion.
Default: no default
EXCLUSIONS
LocalNet STRING
Messages originating from these hosts/networks will not be
scanned. This option takes a host(name)/mask pair in CIRD
notation and can be repeated several times. If "/mask" is
omitted, a host is assumed. To specify a locally orignated, non-
smtp, email use the keyword "local"
Default: unset (scan everything regardless of the origin)
Whitelist STRING
This option specifies a file which contains a list of basic
POSIX regular expressions. Addresses (sent to or from - see
below) matching these regexes will not be scanned. Optionally
each line can start with the string "From:" or "To:" (note: no
whitespace after the colon) indicating if it is, respectively,
the sender or recipient that is to be whitelisted. If the field
is missing, "To:" is assumed. Lines starting with #, : or ! are
ignored.
Default: unset (no exclusion applied)
SkipAuthenticated STRING
Messages from authenticated SMTP users matching this extended
POSIX regular expression (egrep-like) will not be scanned. As
an alternative, a file containing a plain (not regex) list of
names (one per line) can be specified using the prefix "file:".
e.g. SkipAuthenticated file:/etc/good_guys. Note: this is the
AUTH login name!
Default: unset (no whitelisting based on SMTP auth)
SkipAuthenticated SIZE
Messages larger than this value won't be scanned. Make sure this
value is lower or equal than StreamMaxLength in clamd.conf
Default: 25M
ACTIONS
The following group of options controls the delievery process under
different circumstances. The following actions are available:
- Accept: The message is accepted for delievery
- Reject: Immediately refuse delievery (a 5xx error is returned to the
peer)
- Defer: Return a temporary failure message (4xx) to the peer
- Blackhole (not available for OnFail): Like Accept but the message is
sent to oblivion
- Quarantine (not available for OnFail): Like Accept but message is
quarantined instead of being delivered. NOTE: In Sendmail the
quarantine queue can be examined via mailq -qQ. For Postfix this causes
the message to be placed on hold.
OnClean STRING
Action to be performed on clean messages (mostly useful for
testing)
Default: Accept
OnInfected STRING
Action to be performed on infected messages
Default: Quarantine
OnFail STRING
Action to be performed on error conditions (this includes
failure to allocate data structures, no scanners available,
network timeouts, unknown scanner replies and the like)
Default: Defer
RejectMsg STRING
This option allows to set a specific rejection reason for
infected messages and it's therefore only useful together with
"OnInfected Reject". The string "%v", if present, will be
replaced with the virus name.
Default: MTA specific
AddHeader STRING
If this option is set to "Replace" (or "Yes"), an "X-Virus-
Scanned" and an "X-Virus-Status" headers will be attached to
each processed message, possibly replacing existing headers. If
it is set to Add, the X-Virus headers are added possibly on top
of the existing ones. Note that while "Replace" can potentially
break DKIM signatures, "Add" may confuse procmail and similar
filters.
Default: no
ReportHostname STRING
When AddHeader is in use, this option allows to arbitrary set
the reported hostname. This may be desirable in order to avoid
leaking internal names. If unset the real machine name is used.
Default: disabled
VirusAction STRING
Execute a command (possibly searching PATH) when an infected
message is found. The following parameters are passed to the
invoked program in this order: virus name, queue id, sender,
destination, subject, message id, message date. Note #1: this
requires MTA macroes to be available (see LogInfected below).
Note #2: the process is invoked in the context of clamav-milter.
Note #3: clamav-milter will wait for the process to exit. Be
quick or fork to avoid unnecessary delays in email delievery.
Default: disabled
LOGGING OPTIONS
LogFile STRING
Enable logging to selected file.
Default: no
LogFileUnlock BOOL
Disable a system lock that protects against running clamd with
the same configuration file multiple times.
Default: no
LogFileMaxSize SIZE
Limit the size of the log file. The logger will be automatically
disabled if the file is greater than SIZE. Value of 0 disables
the limit.
Default: 1M
LogTime BOOL
Log time for each message.
Default: no
LogSyslog BOOL
Use system logger (can work together with LogFile).
Default: no
LogFacility STRING
Specify the type of syslog messages - please refer to 'man
syslog' for facility names.
Default: LOG_LOCAL6
LogVerbose BOOL
Enable verbose logging.
Default: no
LogInfected STRING
Specify the type of syslog messages - please refer to 'man
syslog' for facility names.
This option allows to tune what is logged when a message is
infected. Possible values are Off (the default - nothing is
logged), Basic (minimal info logged), Full (verbose info logged)
Note: For this to work properly in sendmail, make sure the
msg_id, mail_addr, rcpt_addr and i macroes are available in eom.
In other words add a line like: Milter.macros.eom={msg_id},
{mail_addr}, {rcpt_addr}, i to your .cf file. Alternatively use
the macro: define(`confMILTER_MACROS_EOM', `{msg_id},
{mail_addr}, {rcpt_addr}, i')
Postfix should be working fine with the default settings.
Default: disabled
NOTES
All options expressing a size are limited to max 4GB. Values in excess
will be resetted to the maximum.
FILES
/etc/clamav/clamav-milter.conf
AUTHOR
aCaB <acab@clamav.net>
SEE ALSO
clamav-milter(8), clamd(8), clamd.conf(5)