NAME
fdm.conf - fdm configuration file
DESCRIPTION
This manual page describes the fdm(1) configuration file. It defines
accounts from which to fetch mail, a number of possible actions to take,
and rules connecting a regexp with an action. The file is parsed once
from top to bottom, so action and account definitions must appear before
they are referenced in a rule. Rules are evaluated from first to last
and (unless overridden by the continue keyword) evaluation stops at the
first match.
The file has the following format:
Empty lines and lines beginning with the ‘#’ character are ignored.
Regexps and strings must be enclosed in double quotes. Special
characters in regexps and strings (including passwords) must be escaped.
Note that this may mean double-escaping in regexps.
Possible commands are covered in the following sections.
OPTIONS
Options are configured using the set command. It may be followed by the
following options, one per command:
maximum-size size
This is used to set the maximum size of a mail. Mails larger
than this limit are dropped and, if applicable, not deleted from
the server.
The size may be specified as a plain number in bytes or with a
suffix of ‘K’ for kilobytes, ‘M’ for megabytes or ‘G’ for
gigabytes. The default is one gigabyte.
delete-oversized
If this option is specified, fdm(1) attempts to delete messages
which exceed maximum-size, and continue. If it is not specified,
oversize messages are a fatal error and cause fdm(1) to abort.
Note that fdm(1) may have a number of messages queued (up to the
queue-high setting, doubled for rewrite, per account), so this
setting and the queue-high option should be set after
consideration of the space available in the temporary folder and
the implications should fdm(1) abort due to the space becoming
full.
queue-high number
This sets the maximum number of messages fdm(1) will hold
simultaneously. fdm(1) will attempt to process previously queued
messages as the next is being fetched. Once this limit is
reached, no further messages wil be fetched until the number of
messages held drops to the queue-low value.
queue-low number
This is the length to which the message queue must drop before
fetching continues after the queue-high limit has been reached.
allow-multiple
If this option is specified, fdm(1) does not attempt to create a
lock file and allows multiple instances to run simultaneously.
lock-file path
This sets an alternative lock file. The default is ~/.fdm.lock
for non-root users and /var/db/fdm.lock for root.
command-user user
This specifies the user used to run exec and pipe actions. By
default it is the user who invoked fdm.
default-user user
This sets the default user to change to before delivering mail,
if fdm(1) is running as root and no alternative user is specified
as part of the action or rule. This option may be overridden
with the -u switch on the command line. A default user must be
given if running as root.
lookup-order location ...
This specifies the order in which to do user lookup from left to
right. Possible types are passwd to use the passwd(5) file, or
courier to use Courier authlib (if support is compiled).
lock-types type ...
This specifies the locks to be used for mbox locking. Possible
types are fcntl, flock, and dotlock. The flock and fcntl types
are mutually exclusive. The default is flock.
proxy url
This instructs fdm(1) to proxy all connections through url. HTTP
and SOCKS5 proxies are supported at present (URLs of the form
http://host[:port] or socks://[user:pass@]host[:port]). No
authentication is supported for HTTP.
unmatched-mail drop | keep
This option controls what fdm(1) does with mail that reaches the
end of the ruleset (mail that matches no rules or matches only
rules with the continue keyword). drop will cause such mail to
be discarded, and keep will attempt to leave the mail on the
server. The default is to keep the mail and log a warning that
it reached the end of the ruleset.
purge-after count
The purge-after option makes fdm(1) attempt to purge deleted mail
from the server (if supported) after count mails have been
retrieved. This is useful on unreliable connections to limit the
potential number of mails refetched if the connetion drops, but
note that it can incur a considerable speed penalty.
no-received
If this option is present, fdm(1) will not insert a ‘Received’
header into each mail.
no-create
If this option is set, fdm(1) will not attempt to create maildirs
and mboxes or missing elements of their paths.
file-umask user | umask
This specifies the umask(2) to use when creating files. user
means to use the umask set when fdm(1) is started, or umask may
be specified as a three-digit octal number. The default is 077.
file-group user | group
This option allows the default group ownership of files and
directories created by fdm(1) to be specified. group may be a
group name string or a numeric gid. If user is used, or this
option does not appear in the configuration file, fdm(1) does not
attempt to set the group of new files and directories.
timeout time
This controls the maximum time to wait for a server to send data
before closing a connection. The default is 900 seconds.
verify-certificates
Instructs fdm(1) to verify SSL certificates for all SSL
connections.
INCLUDING FILES
Further configuration files may be including using the include command:
include path
The file to include is searched for first as an absolute path and then
relative to the directory containing the main configuration file.
MACROS
Macros may be defined using the following syntax:
$name = string
%name = number
Macros are prefixed with $ to indicate a string value and % to indicate a
numeric value. Once defined, a macro may be used in any place a string
or number is expected. Macros may be embedded in strings by surrounding
their name (after the $ or %) with {}s, like so:
"abc ${mymacro} %{anothermacro} def"
The ifdef, ifndef and endif keywords may be used to conditionally parse a
section of the configuration file depending on whether or not the macro
given exists or does not exist. ifdef and ifndef blocks may be nested.
SHELL COMMANDS
The result of a shell command may be used at any point a string or number
is expected by wrapping it in $() or %(). If the former is used, the
command result is used as a string; if the latter, it is converted to an
integer. Shell commands are executed when the configuration file is
parsed.
ACCOUNTS
The account command is used to instruct fdm(1) to fetch mail from an
account. The syntax is:
account name [users] [disabled] type [args] [keep]
The name argument is a string specifying a name for the account. The
optional users argument has the following form:
user user | users { user ... }
The first two options specify a user or list of users as which the mail
should be delivered when an action is executed. If no users are
specified, the default user (set with set default-user) is used. Users
specified as part of the account definition may be overridden by similar
arguments to action definitions or on match rules. If fdm(1) is run as
non-root, it will still execute any actions once for each user, but will
be unable to change to that user so the action will be executed multiple
times as the current user.
The disabled keyword instructs fdm(1) to ignore this account unless it is
explicitly enabled with a -a option on the command line. If the keep
keyword is specified, all mail collected from this account is kept (not
deleted) even if it matches a drop action.
Supported account types and arguments are:
stdin This account type reads mail from stdin, if it is connected to a
pipe. This may be used to deliver mail from sendmail(8), see
fdm(1) for details.
pop3 server host [port port] [user user] [pass pass] [only] [no-apop]
pop3s server host [port port] [userpass] [only] [no-apop] [no-verify]
These statements define a POP3 or POP3S account. The userpass
element has the following form:
[user user] [pass pass]
The host, user and pass arguments must be strings. If the user
or pass is not provided, fdm(1) attempts to look it up in the
~/.netrc file (see ftp(1) for details of the file format). The
port option may be either a string which will be looked up in the
services(5) database, or a number. If it is omitted, the default
port (110 for POP3, 995 for POP3S) is used.
The only option takes the form:
[new-only | old-only] cache path
new-only fetches only mail not previously fetched, and old-only
is the inverse: it fetches only mail that has been fetched
before. The cache file is used to save the state of the POP3
mailbox. The no-apop flag forces fdm(1) not to use the POP3 APOP
command for authentication, and the no-verify keyword instructs
fdm(1) to skip SSL certificate validation for this account.
pop3 pipe command [userpass] [only] [no-apop]
This account type uses the POP3 protocol piped through command,
such as ssh(1). If the command produces any output to stderr, it
is logged. For POP3 over a pipe, providing a user and password
is not optional and it may not be read from ~/.netrc.
imap server host [port port] [userpass] [folder name] [only]
[no-cram-md5] [no-login]
imap server host [port port] [userpass] [folders] { name ... } [only]
imaps server host [port port] [userpass] [folders] [only] [no-verify]
[no-cram-md5] [no-login]
These define an IMAP or IMAPS account. The parameters are as for
a POP3 or POP3S account, aside from the additional folders option
which sets the name of the folder or folders to use (the default
is to fetch from the inbox). This has the form:
folder name | folders { name ... }
The default ports used are 143 for IMAP and 993 for IMAPS. For
IMAP, the only item consists only of one of the keywords new-only
or old-only - a cache file is not required.
Options no-cram-md5 and no-login disable the given authentication
method. The default is to use CRAM-MD5 if it is available, or
LOGIN otherwise.
imap pipe command [userpass] [folders] [only]
As with pop3 pipe, this account type uses the IMAP protocol piped
through command. If the optional IMAP user and pass are
supplied, they will be used if necessary, but if one is provided,
both must be - using ~/.netrc is not permitted.
maildir path
maildirs { path ... }
These account types instruct fdm(1) to fetch mail from the
maildir or maildirs specified. This allows fdm(1) to be used to
filter mail, fetching from a maildir and deleting (dropping)
unwanted mail, or delivering mail to another maildir or to an
mbox.
mbox path
mboxes { path ... }
These are similar to maildir and maildirs, but cause fdm(1) to
fetch mail from an mbox or set of mboxes.
nntp server host [port port] group group cache cache
nntp server host [port port] groups { group ... } cache cache
nntps server host [port port] group group cache cache
nntps server host [port port] groups { group ... } cache cache
An NNTP account. Articles are fetched from the specified group
or groups and delivered. The index and message-id of the last
article fetched in each group is saved in the specified cache
file. When fdm(1) is run again, fetching begins at the cached
article.
Note that the keep option is completely ignored for NNTP accounts - all
mail is kept, and the cache is always updated.
TAGGING
As mail is processed by fdm(1), it is tagged with a number of name/value
pairs. Some tags are added automatically, and mail may also be tagged
explicitly by the user using the tag action. Tags may be inserted in
most strings in a similar manner to macros, except tags are processed at
runtime rather than as the configuration file is parsed. A tag’s value
is inserted by wrapping its name in %[], for example:
abc%[account]def
%[hour]:%[minute]:%[second]
The default tags also have a single-letter shorthand. Including a
nonexistent tag in a string is equivalent to including a tag with an
empty value, so "abc%[nonexistent]def" will be translated to "abcdef".
The automatically added tags are:
account (%a)
The name of the account from which the mail was fetched.
home (%h)
The delivery user’s home directory.
uid (%n)
The delivery user’s uid.
action (%t)
The name of the last action executed for this mail.
user (%u)
The delivery user’s username.
hour (%H)
The current hour (00-23).
minute (%M)
The current minute (00-59).
second (%S)
The current second (00-59).
day (%d)
The current day of the month (01-31).
month (%m)
The current month (01-12).
year (%y)
The current year.
year2 The current year as two digits.
dayofweek (%W)
The current day of the week (0-6, Sunday is 0).
dayofyear (%Y)
The current day of the year (001-366).
quarter (%Q)
The current quarter (1-4).
rfc822date
The current date in RFC822 format.
mail_hour
The hour from the mail’s date header, if it exists and is
valid, otherwise the current time.
mail_minute
The minute from the mail’s date header.
mail_second
The second from the mail’s date header.
mail_day
The day from the mail’s date header.
mail_month
The month from the mail’s date header.
mail_year
The year from the mail’s date header.
mail_year2
The same as two digits.
mail_rfc822date
The mail’s date in RFC822 format.
hostname
The local hostname.
In addition, the shorthand %% is replaced with a literal %, and %0 to %9
are replaced with the result of any bracket expressions in the last
regexp.
CACHES
fdm(1) can maintain a cache file with a set of user-defined strings. In
order to use caches, fdm(1) must have been compiled with them enabled.
Caches are declared with the cache keyword:
cache path [expire age]
The path is the location of the cache file. If the expire keyword is
specified, items in the cache are removed after they reach the age
specified. age may be given unadorned in seconds, or followed by one of
the modifiers: seconds, hours, minutes, days, months or years.
Caches must be declared before they are used. Items are added to caches
using the add-to-cache action, removed using the remove-from-cache
action, and searched for using the in-cache condition; see below for
information on these.
ACTIONS
The action command is used to define actions. These may be specified by
name in rules (see below) to perform some action on a mail. The syntax
is:
action name [users] action
action name [users] { action ... }
The name is a string defining a name for the action. The users argument
has the same form as for an account definition. An action’s user setting
may be overridden in the matching rule.
The possible values for action are listed below. If multiple actions are
specified they are executed once in the order specified, for each user.
drop Discard the mail.
keep Keep the mail, do not remove it from the account.
tag string [value value]
This tags mail with string, and optionally value, which may be
matched using the tagged or string conditions.
maildir path
Save the mail to the maildir specified by path. If the maildir
or any part of its path does not exist, it is created, unless the
no-create option is set.
Mail delivered to a maildir is tagged with a mail_file tag
containing the full path of the mail file.
mbox path [compress]
Append the mail to the mbox at path. If compress is specified,
fdm(1) will add ‘.gz’ to path and attempt to write mail using
gzip(1) compression. If the mbox or any part of its path does
not exist, it is created, unless the no-create option is set.
Mail delivered to an mbox is tagged with a mbox_file tag
containing the path of the mbox.
exec command
Execute command.
pipe command
Pipe the mail to command. exec and pipe commands are run as the
command user.
write path
Write the mail to path.
append path
Append the mail to path.
smtp server host [port port] [from from] [to to]
Connect to an SMTP server and attempt to deliver the mail to it.
If from or to is specified, they are passed to the server in the
MAIL FROM or RCPT TO commands. If not, the current user and host
names are used.
rewrite command
Pipe the entire mail through command to generate a new mail and
use that mail for any following actions or rules. An example of
the rewrite action is:
action "cat" pipe "cat"
action "rewrite" rewrite "sed ’s/bob/fred/g’"
# this rule will rewrite the message
match all action "rewrite" continue
# this rule will cat the rewritten message
match all action "cat"
add-header name value value
Add a header name with contents value.
remove-header name
remove-headers { name ... }
Remove all occurances of headers matching the fnmatch(3) pattern
name.
stdout Write the mail to stdout.
add-to-cache path key key
This action adds the string key to the cache specified by path.
If key already exists in the cache, it is replaced.
remove-from-cache path key key
Remove the string key from the cache path, if a matching key is
present.
action name
This invokes another named action. A maximum of five actions may
be called in a sequence.
RULES
Rules are specified using the match keyword. It has the following basic
form:
match condition [and | or condition ...] [users] actions [continue]
The condition argument may be one of:
all Matches all mail.
matched
Matches only mail that has matched a previous rule and been
passed on with continue.
unmatched
The opposite of matched: matches only mails which have matched no
previous rules.
account name | accounts { name ... }
Matches only mail fetched from the named account or accounts.
The account names may include shell glob wildcards to match
multiple accounts, as with the -a and -x command line options.
tagged string
Matches mails tagged with string.
[case] regexp [in headers | in body]
Specifies a regexp against which each mail should be matched.
The regexp matches may be restricted to either the headers or
body of the message by specifying either in headers or in body.
The case keyword forces the regexp to be matched case-
sensitively: the default is case-insensitive matching.
exec command [user user] returns ( return code, stdout regexp)
pipe command [user user] returns ( return code, [case] stdout regexp)
These two conditions execute a command and test its return value
and output. The return code argument is the numeric return code
expected and stdout regexp is a regexp to be tested against the
output of the command to stdout. Either of these two arguments
may be omitted: if both are specified, both must match for the
condition to be true. The pipe version will pipe the mail to the
command’s stdin when executing it. If a user is specified,
fdm(1) will change to that user before executing the command,
otherwise the current user (or root if started as root) is used.
size < number
size > number
Compare the mail size with number.
string string to [case] regexp
Match string against regexp.
age < time
age > time
The age condition examines the mail’s date header to determine
its age, and matches if the mail is older (>) or newer (<) than
the time specified. The time may be given as a simple number in
seconds, or followed by the word seconds, hours, minutes, days,
months or years to specify a time in different units.
in-cache path key key
This condition evaluates to true if the string key is in the
cache at path.
attachment count < number
attachment count > number
attachment count == number
attachment count != number
These conditions match if the mail possesses a number of
attachments less than, greater than, equal to or not equal to
number.
attachment total-size < size
attachment total-size > size
Matches if the total size of all attachments is smaller or larger
than size.
attachment any-size < size
attachment any-size > size
Compare each individual attachment on a mail to size and match if
any of them are smaller or larger.
attachment any-type string
attachment any-name string
Match true if any of a mail’s attachments possesses a MIME type
or filename that matches string. fnmatch(3) wildcards may be
used.
Multiple conditions may be chained together using the and or or keywords.
The conditions are tested from left to right. Any condition may be
prefixed by the not keyword to invert it.
The optional users argument to the first form has the same syntax as for
an action definition. A rule’s user list overrides any users given as
part of the actions.
The actions list specifies the actions to perform when the rule matches a
mail. It is either of a similar form:
action name | actions { name ... }
Or may specify a number of actions inline (lambda actions):
action action
action { action ... }
In the latter case, action follows the same form as described in the
ACTIONS section. The actions are performed from first to last in the
order they are specified in the rule definition.
If the continue keyword is present, evaluation will not stop if this rule
is matched. Instead, fdm(1) will continue to match further rules after
performing any actions for this rule.
NESTED RULES
Rules may be nested by specifying further rules in braces:
match condition [and | or condition ...] {
match ...
}
The inner rules will not be evaluated unless the outer one matches.
Rules may be multiply nested. Note that the outer rule does not count as
a match for the purposes of the matched and unmatched conditions.
FILES
~/.fdm.conf default fdm.conf configuration file
/etc/fdm.conf default system-wide configuration file
~/.fdm.lock default lock file
/var/db/fdm.lock lock file for root user
SEE ALSO
fdm(1), re_format(7)
AUTHORS
Nicholas Marriott 〈nicm@users.sourceforge.net〉