- Configuration file for opendmarc
implements the proposed DMARC
message authentication, policy enforcement, and reporting. This file is its
Blank lines are ignored. Lines containing a hash ("#") character are
truncated at the hash character to allow for comments in the file.
Other content should be the name of a parameter, followed by white space,
followed by the value of that parameter, each on a separate line.
For parameters that are Boolean in nature, only the first byte of the value is
processed. For positive values, the following are accepted: "T",
"t", "Y", "y", "1". For negative
values, the following are accepted: "F", "f",
"N", "n", "0".
Some, but not all, of these parameters are also available as command line
options to opendmarc(8).
However, new parameters are generally not
added as command line options so the complete set of options is available
here, and thus use of the configuration file is encouraged. In some future
release, the set of available command line options is likely to get trimmed.
See the opendmarc(8)
man page for details about how and when the
configuration file contents are reloaded.
Unless otherwise stated, Boolean values default to "false", integer
values default to 0, and string and dataset values default to being undefined.
- AuthservID (string)
- Sets the "authserv-id" to use when generating the
Authentication-Results: header field after verifying a message. The
default is to use the name of the MTA processing the message. If the
string "HOSTNAME" is provided, the name of the host running the
filter (as returned by the gethostname(3) function) will be used.
- AuthservIDWithJobID (Boolean)
- If "true", requests that the authserv-id portion
of the added Authentication-Results: header fields contain the job ID of
the message being evaluated.
- AutoRestart (Boolean)
- Automatically re-start on failures. Use with caution; if
the filter fails instantly after it starts, this can cause a tight
- AutoRestartCount (integer)
- Sets the maximum automatic restart count. After this number
of automatic restarts, the filter will give up and terminate. A value of 0
implies no limit; this is the default.
- AutoRestartRate (string)
- Sets the maximum automatic restart rate. If the filter
begins restarting faster than the rate defined here, it will give up and
terminate. This is a string of the form n/t[u] where n is an
integer limiting the count of restarts in the given interval and
t[u] defines the time interval through which the rate is
calculated; t is an integer and u defines the units thus
represented ("s" or "S" for seconds, the default;
"m" or "M" for minutes; "h" or "H"
for hours; "d" or "D" for days). For example, a value
of "10/1h" limits the restarts to 10 in one hour. There is no
default, meaning restart rate is not limited.
- Background (Boolean)
- Causes opendmarc to fork and exits immediately,
leaving the service running in the background. The default is
- BaseDirectory (string)
- If set, instructs the filter to change to the specified
directory using chdir(2) before doing anything else. This means any
files referenced elsewhere in the configuration file can be specified
relative to this directory. It's also useful for arranging that any crash
dumps will be saved to a specific location.
- ChangeRootDirectory (string)
- Requests that the operating system change the effective
root directory of the process to the one specified here prior to beginning
execution. chroot (2) requires superuser access. A warning will be
generated if UserID is not also set.
- CopyFailuresTo (string)
- Adds the specified recipient to the message's envelope if
it fails the DMARC evaluation.
- DNSTimeout (integer)
- Sets the DNS timeout in seconds. A value of 0 causes an
infinite wait. The default is 5. Ignored if not using an asynchronous
- EnableCoredumps (Boolean)
- On systems that have such support, make an explicit request
to the kernel to dump cores when the filter crashes for some reason. Some
modern UNIX systems suppress core dumps during crashes for security
reasons if the user ID has changed during the lifetime of the process.
Currently only supported on Linux.
- FailureReports (Boolean)
- Enables generation of failure reports when the DMARC test
fails and the purported sender of the message has requested such reports.
Reports are formatted per RFC6591.
- FailureReportsBcc (string)
- When failure reports are enabled and one is to be
generated, always send one to the address(es) specified here. If a failure
report is requested by the domain owner, the address(es) are added in a
Bcc: field. If no request is made, they address(es) are used in a To:
field. There is no default.
- FailureReportsOnNone (Boolean)
- Supplementary to the previous setting, enables generation
of failure reports for sending domains that publish a "none"
- FailureReportsSentBy (string)
- Sets the value of the From: field to be used when sending
failure reports (see above). The default is to use the userid of the user
executing the filter and the local host name to construct an email
- HistoryFile (string)
- If set, specifies the location of a text file to which
records are written that can be used to generate DMARC aggregate reports.
Records are batches of rows containing information about a single received
message, and include all relevant information needed to generate a DMARC
aggregate report. It is expected that this will not be used in its raw
form, but rather periodically imported into a relational database from
which the aggregate reports can be extracted.
- IgnoreAuthenticatedClients (Boolean)
- If set, causes mail from authenticated clients (i.e., those
that used SMTP AUTH) to be ignored by the filter. The default is
- IgnoreHosts (string)
- Specifies the path to a file that contains a list of
hostnames, IP addresses, and/or CIDR expressions identifying hosts whose
SMTP connections are to be ignored by the filter. If not specified,
defaults to "127.0.0.1" only.
- IgnoreMailFrom (string)
- Gives a list of domain names whose mail (based on the From:
domain) is to be ignored by the filter. The list should be
comma-separated. Matching against this list is case-insensitive. The
default is an empty list, meaning no mail is ignored.
- MilterDebug (integer)
- Sets the debug level to be requested from the milter
library. The default is 0.
- PidFile (string)
- Specifies the path to a file that should be created at
process start containing the process ID.
- PublicSuffixList (string)
- Specifies the path to a file that contains top-level
domains (TLDs) that will be used to compute the Organizational Domain for
a given domain name, as described in the DMARC specification. If not
provided, the filter will not be able to determine the Organizational
Domain and only the presented domain will be evaluated.
- RecordAllMessages (Boolean)
- If set and HistoryFile is in use, all received
messages are recorded to the history file. If not set (the default), only
messages for which the From: domain published a DMARC record will be
recorded in the history file.
- RejectFailures (Boolean)
- If set, messages will be rejected if they fail the DMARC
evaluation, or temp-failed if evaluation could not be completed. By
default, no message will be rejected or temp-failed regardless of the
outcome of the DMARC evaluation of the message. Instead, an
Authentication-Results header field will be added. The default is
- RejectString (string)
- This string describes the reason of reject at SMTP level.
The message MUST contain the word "%s" once, which will be
replaced by the RFC5322.From domain. The default is "rejected by
DMARC policy for %s"
- ReportCommand (string)
- Indicates the shell command to which failure reports should
be passed for delivery when FailureReports is enabled. Defaults to
- RequiredHeaders (Boolean)
- If set, the filter will ensure the header of the message
conforms to the basic header field count restrictions laid out in RFC5322,
Section 3.6. Messages failing this test are rejected without further
processing. A From: field from which no domain name could be extracted
will also be rejected.
- Socket (string)
- Specifies the socket that should be established by the
filter to receive connections from sendmail(8) in order to provide
service. socketspec is in one of two forms: local:path,
which creates a UNIX domain socket at the specified path, or
inet:port[@host] or inet6:port[@host] which creates a TCP
socket on the specified port for the appropriate protocol family.
If the host is not given as either a hostname or an IP address, the
socket will be listening on all interfaces. This option is mandatory
either in the configuration file or on the command line. If an IP address
is used, it must be enclosed in square brackets.
- SoftwareHeader (Boolean)
- Causes opendmarc to add a "DMARC-Filter"
header field indicating the presence of this filter in the path of the
message from injection to delivery. The product's name, version, and the
job ID are included in the header field's contents.
- SPFIgnoreResults (Boolean)
- Causes the filter to ignore any SPF results in the header
of the message. This is useful if you want the filter to perfrom SPF
checks itself, or because you don't trust the arriving header. The default
- SPFSelfValidate (Boolean)
- Causes the filter to perform a fallback SPF check itself
when it can find no SPF results in the message header. If SPFIgnoreResults
is also set, it never looks for SPF results in headers and always performs
the SPF check itself when this is set. The default is "false".
- Syslog (Boolean)
- Log via calls to syslog(3) any interesting activity.
- SyslogFacility (string)
- Log via calls to syslog(3) using the named facility.
The facility names are the same as the ones allowed in
syslog.conf(5). The default is "mail".
- TrustedAuthservIDs (string)
- Provides a list of authserv-ids that are to be used to
identify Authentication-Results header fields whose contents are to be
assumed as valid input for the DMARC assessment. To provide a list,
separate values by commas. If the string "HOSTNAME" is provided,
the name of the host running the filter (as returned by the
gethostname(3) function) will be used. Matching against this list
is case-insensitive. The default is to use the value of AuthservID.
- UMask (integer)
- Requests a specific permissions mask to be used for file
creation. This only really applies to creation of the socket when
Socket specifies a UNIX domain socket, and to the PidFile
(if any); temporary files are created by the mkstemp(3) function
that enforces a specific file mode on creation regardless of the process
umask. See umask(2) for more information.
- UserID (string)
- Attempts to become the specified userid before starting
operations. The value is of the form userid[:group]. The process
will be assigned all of the groups and primary group ID of the named
userid unless an alternate group is specified.
- Default location of this file.
This man page covers version 1.3.2 of opendmarc.
Copyright (c) 2012-2015, The Trusted Domain Project. All rights reserved.
RFC4408 - Sender Policy Framework
RFC5451 - Message Header Field for Indicating Message Authentication Status
RFC5965 - An Extensible Format for Email Feedback Reports
RFC6376 - DomainKeys Identified Mail
RFC6591 - Authentication Failure Reporting Using the Abuse Reporting