DESCRIPTION
clamsmtpd(8) reads a configuration file when starting up. The location of the file is dependent on how you compiled clamsmtp but it should usually be in either the /usr/local/etc/ or /etc/ directories. If clamsmtpd(8) does not find its configuration file it'll print a warning when it starts up along with the location it's expecting to find it in. You can also specify a different location for a config file by passing the -f argument to clamsmtpd(8)The settings are specified one per line. The setting names come first, followed by a colon and then the value. Comments start with the '#' character on a line of their own. Whitespace is ignored at the beginning of line, end of line and around the colons.
A sample configuration file can be found in the doc/ directory of the clamsmtp distribution.
SETTINGS
The various settings are as follows:- Action
-
This option controls what
clamsmtpd(8)
does when it finds a virus. The options are:
- bounce
- Bounce the email. In most cases this is not a good idea since many viruses spoof sender addresses.
- drop
- Silently drop the email. Recommended.
- pass
- Pass on the email. Inserts an 'X-Virus-Infected' header.
[ Default: drop ]
- ClamAddress
-
Specifies the address to connect to
clamd(8)
on. See syntax of addresses below.
[ Default: /var/run/clamav/clamd ]
- Header
-
A header to add to scanned messages. Put an empty value to suppress adding
a header. You can include the following special formatting characters in the
string to include special values:
- %i
- Client IP Address
- %l
- Local IP Address
- %d
- Current Date
You can also include the standard \r or \n escapes.
[ Default: 'X-Virus-Scanned: ClamAV using ClamSMTP' ]
- KeepAlives
-
On slow connections the server will sometimes timeout before
clamsmtpd(8)
is finished scanning the file. This option sends NOOP's to the server
to keep the connection alive. Specify the number of seconds, or 0
to disable.
[ Default: 0 ]
- Listen
-
The address and port to listen for SMTP connections on. See syntax of
addresses below.
[ Default: port 10025 on all local IP addresses ]
- PidFile
-
Specifies a location for the a process id file to be written to. This file
contains the process id of
and can be used to stop the daemon. If the
-p
argument is passed on the command line, then this setting will be ignored.
[ Default: none ]
- Quarantine
-
Quarantine files that contain viruses by leaving them in the
TempDirectory
directory. The file names look like this (where X is a random
character or number):
virus.XXXXXX
[ Default: off ]
- MaxConnections
-
Specifies the maximum number of connections to accept at once.
clamd(8)
also needs to be setup to accept at least this number of connections.
[ Default: 64 ]
- OutAddress
-
The address of the SMTP server to send email to once it's been scanned. See
syntax of addreses below.
[ Required ]
- TempDirectory
-
The directory to write temp files to. This directory needs to be
accessible to both
clamd(8)
and
clamsmtpd(8)
[ Default: /tmp ]
- TimeOut
-
The number of seconds to wait while reading data from network connections.
[ Default: 180 seconds ]
- TransparentProxy
-
This option enables transparent proxy support, which allows you to route all
SMTP traffic that's going through a gateway through clamsmtp which will then
send it on to its final destination. This setup usually involves firewall
rules which redirect traffic to clamsmtp, and the setup varies from OS to OS.
[ Default: off ]
- User
-
The user to run as. If this option is specified then
clamsmtpd(8)
must be started as root. It will then drop root privileges and run as the
specified user. The user can either be a name or a numerical user id.
[ Optional ]
- VirusAction
-
This is a command to run when a virus is found. See the VIRUS ACTION section
in
clamsmtpd(8)
for a discussion of this option.
[ Default: off ]
- XClient
-
Send an XCLIENT command to the receiving server. This is useful for forwarding
client addresses and connection info to servers that support this feature.
[ Default: off ]
ADDRESSES
Addresses can be specified in multiple formats:- Unix local addresses can be specified by specifying their full path. (ie: '/var/run/clamav/clamd').
- IP addresses can be specified using dotted notation with a colon before the port number (ie: '127.0.0.1:3310').
- IPv6 addresses are implemented but disabled. The code needs testing.