-.\" $Id: t-prot.1,v 1.151 2010/02/07 22:10:06 jochen Exp $
+.\" $Id: t-prot.1,v 1.192 2015/03/26 08:59:50 jochen Exp $
.\"
-.TH T-PROT "1" "February 2010" "T-PROT"
+.TH T-PROT "1" "March 2015" "T-PROT"
.SH NAME
t-prot \- TOFU Protection - Display Filter for RFC 5322 messages
.SH SYNOPSIS
.br
The filter is written in Perl and relies on input to be a single
message conforming to RFC 822 or its successors, RFC 2822 and RFC 5322.
-Messages conforming to RFCs 2045-2049 should be treated reasonably correct.
+In messages conforming to MIME (RFCs 2045-2049) t\-prot handles text/plain
+parts, others are not touched.
.PP
Already reformatted messages are handled well: the script was
initially designed to cope with the output of the MUA mutt (which
is the reason for not using standard CPAN modules for handling
messages).
.PP
-For easy usage, you can include the file muttrc.t\-prot in your
-~/.muttrc. Also coming with the t-prot package is the example S-Lang
-macro t\-prot.sl for using t-prot from within slrn. There is a
-proof\-of\-concept filter for INN2, which you will have to adapt to
-the needs of the news site you host (please see the file for details).
+T\-prot offers example configuration files for mutt and its fork mutt\-kz,
+Heirloom mailx and metamail. Also coming with the t-prot package is the
+example S-Lang macro t\-prot.sl for using t-prot from within slrn. There
+is a proof\-of\-concept filter for INN2, which you will have to adapt
+to the needs of the news site you host. For use with sendmail's
+alias(5) file, please see below (the option
+.BR "\-p" " provides an example line)."
.SH OPTIONS
+.PP
+If you do not specify any options, t\-prot does ... nothing. Every
+feature you want must be turned on explicitly.
+Admittedly, we have quite a number of options for t\-prot. To limit
+confusion they are grouped into five sections: Input/Output Options,
+Advertisement And Mailing List Footers, Filtering Options, Detection
+Options, and Other Options. While the others should be quite clear,
+filtering and detection might deserve a word (or two).
+.PP
+If you want to tune the appearance of your mail from within your MUA
+(or news messages from within your NUA), then go for the Filtering
+Options section.
+.PP
+If you want to use t\-prot to check on mails before they are submitted
+to mailing lists, fed to your news server, or delivered by your MDA,
+then have a peek at the Detection Options section. You may accept or
+reject/bounce messages depending on t\-prot's result.
+.SH INPUT/OUTPUT OPTIONS
.TP
-.BR "\-A" =DIRECTORY
-"ad footer directory":
-Defines the directory which contains the advertisement list footers (one
-footer per file) which are to be tested when removing them with options
-.B \-a
-or
-.BR \-\-ftr\-ad .
-.br
-This option is also needed if you do not want signature lengths to be
-counted wrong or fullquotes get undetected when an ad footer is
-appended at the bottom of the message (especially when using
-.B "\-S"
-or
-.BR "\-t" ).
+.BR "\-i" " FILE"
+Defines an input file; default is '\-' i.e. STDIN.
+.TP
+.BR "\-o" " FILE"
+Defines the output file; default is STDOUT.
+.TP
+.B "\-\-body"
+Input consists just of the message's body. There are no RFC 5322 header
+lines.
+.IP
+.IR NOTE :
+This does not work with \-\-pgp\-short, and multipart messages will not
+be detected due to missing headers.
+.TP
+.B "\-\-lax\-security"
+Allow insecure writing method. DO NOT USE UNLESS YOU REALLY KNOW WHAT
+YOU ARE DOING. (This ugly workaround is needed for some early mutt versions
+and should NEVER be used as a default, otherwise it will probably turn into
+a security issue.)
+.sp
+You can use this option safely to enable
+.B "\-o"
+/dev/null (or other files which cannot be changed with the user's
+privileges).
+.TP
+.BR "\-\-max\-lines" =x
+Maximum number of lines a message may count (with headers). If the message
+is longer than x lines, the message will not be processed but printed
+unmodified. Exit status will be EX_DATAERR except when called with \-Mmutt
+or \-Mmutt\-kz.
+.SH ADVERTISEMENT AND MAILING LIST FOOTERS
.TP
.B "\-a"
"commercial signature":
.br
This option compares the last lines of the message body with any
footer file found in the directory specified with
-.BR "\-A" =DIRECTORY
+.BR "\-A" " DIRECTORY"
(which is mandatory for this option). The comparison is done by perl's
.B index()
function (please try
.B \-\-ftr\-ad
is specified.
.TP
-.BR "\-\-bigq" [=n[,x]]
-"shrink big quotes":
-Blocks of quotes with more than n lines will be shrunk to x lines.
-Defaults are 30 for n and 10 for x.
-.TP
-.B "\-\-body"
-Input consists just of the message's body. There are no RFC 5322 header
-lines.
-.IP
-.IR NOTE :
-This does not work with \-\-pgp\-short, and multipart messages will not
-be detected due to missing headers.
-.TP
-.B "\-c"
-"compress":
-Squeezes a sequence of blank lines to just two blank lines.
-.TP
-.BR "\-\-check" [=FLAGS]
-Run checks. If successful, print an error message and quit with
-an appropriate exit code. Useful e.g. for rejecting messages from
-within INN2.
-.IP
-Flags are separated by commas (no whitespaces), and can be the
-following (right now just one flag):
-.IP
-.IR ratio [=n]
-.br
-If the quoting ratio is n or more, the message is rejected. Must be
-between 0 and 1, or else it is entirely disabled. Default is 0.75
-(i.e., 75% of the message lines are quotes).
-.TP
-.B "\-d, \-\-debug"
-Print envelope info to syslog when bouncing TOFU contaminated email.
-Default syslog facility is mail.debug. Requires
-.BR \-p .
-.TP
-.B "\-\-diff"
-"tolerate diff":
-Tolerate unified diff (see
-.BR diff (1)
-and
-.BR patch (1))
-appended *after* the signature (which usually makes the signature too long
-to be valid). Not entirely consequent but sometimes useful, e.g. at the
-Linux kernel mailing list.
-.TP
-.B "\-e"
-"ellipsis":
-Squeezes a sequence of four or more dots, exclamation marks, or question marks
-to only three dots or marks, respectively.
-.TP
.B "\-\-ftr\-ad"
"enable aggressive ad footer matching":
With this option enabled, t-prot makes footer detection really greedy: We
.sp
.IR NOTE :
This requires a directory with footer files to be given with option
-.BR "\-A" =DIRECTORY.
+.BR "\-A" " DIRECTORY".
+.TP
+.BR "\-A" " DIRECTORY"
+"ad footer directory":
+Defines the directory which contains the advertisement list footers (one
+footer per file) which are to be tested when removing them with options
+.B \-a
+or
+.BR \-\-ftr\-ad .
+.br
+This option is also needed if you do not want signature lengths to be
+counted wrong or fullquotes get undetected when an ad footer is
+appended at the bottom of the message (especially when using
+.B "\-S"
+or
+.BR "\-t" ).
+.TP
+.B "\-l"
+"list signature":
+Hides "footers" (signatures) from mailing lists. Footer detection works like the
+.B "\-a"
+option.
+.sp
+.IR NOTE :
+This requires a directory with footer files to be given with option
+.BR "\-L" " DIRECTORY".
+.B \-l
+is not needed if
+.B \-\-ftr\-ml
+is specified.
.TP
.B "\-\-ftr\-ml"
"enable aggressive mailing list footer matching":
.sp
.IR NOTE :
This requires a directory with footer files to be given with option
-.BR "\-L" =DIRECTORY.
+.BR "\-L" " DIRECTORY".
.TP
-.B "\-\-groupwise"
-Hides TOFU as produced by Novell Groupwise.
+.BR "\-L" " DIRECTORY"
+"list footer directory":
+Defines the directory which contains the mailing list footers (one footer
+per file) which are to be tested when removing them with the options
+.B \-l
+or
+.BR \-\-ftr\-ml .
+.br
+This option is also needed if you do not want signature lengths to be
+counted wrong or fullquotes get undetected when a mailing list footer is
+appended at the bottom of the message (especially when using
+.B "\-S"
+or
+.BR "\-t" ).
+.SH FILTER OPTIONS
.TP
-.B "\-h, \-\-help"
-Displays a short help text with a summary on all options, and exits.
+.BR "\-\-bigq" [=n[,x]]
+"shrink big quotes":
+Blocks of quotes with more than n lines will be shrunk to x lines.
+Defaults are 30 for n and 10 for x.
+.TP
+.BR "\-c" "[n]"
+"compress":
+Squeezes a sequence of blank lines to just n blank lines. n defaults to 2.
+.TP
+.B "\-\-diff"
+Tolerate unified diff (see
+.BR diff (1)
+and
+.BR patch (1))
+appended after the signature (which usually makes the signature too long
+to be valid).
+.sp
+Also, protect diff standard output from hiding (which would otherwise be easy
+prey for
+.BR "\-t" ).
.TP
-.BR "\-i" =FILE
-"input file":
-Defines a file for input; the default input is from '\-' i.e. STDIN.
+.B "\-e"
+"ellipsis":
+Squeezes a sequence of four or more dots, exclamation marks, or question marks
+to only three dots or marks, respectively.
+.TP
+.BR "\-\-fixind"
+Fix broken quotes to adhere to RFC 3676 by removing spaces between quote
+characters and adding a space after them.
+.br
+.IR NOTE :
+This may produce false positives if spaces in between quote characters
+are intended (thus changing the quoting level, see RFC 3676 for details).
+.TP
+.B "\-\-groupwise"
+Hides TOFU as produced by Novell Groupwise.
.TP
.B "\-k"
"anti Kammquote":
.IP
Please also note that enabling this option is quite a performance hit.
.TP
-.BR "\-\-kminl" =n
-Minimum line length for wrapped line detection on Kammquotes. For
-details, please see the source code.
+.BR "\-\-kdiff" =n
+Minimum length difference between two lines for wrapped line detection on
+Kammquotes. For details, please see the source code.
.br
Anyway, lower values make the algorithm more aggressive, higher values
-make Kammquotes harder to detect. Default is 65.
+make Kammquotes harder to detect. Default is 20.
.sp
Requires
.BR "\-k" .
Requires
.BR "\-k" .
.TP
-.BR "\-\-kdiff" =n
-Minimum length difference between two lines for wrapped line detection on
-Kammquotes. For details, please see the source code.
+.BR "\-\-kminl" =n
+Minimum line length for wrapped line detection on Kammquotes. For
+details, please see the source code.
.br
Anyway, lower values make the algorithm more aggressive, higher values
-make Kammquotes harder to detect. Default is 20.
+make Kammquotes harder to detect. Default is 65.
.sp
Requires
.BR "\-k" .
.TP
-.BR "\-L" =DIRECTORY
-"list footer directory":
-Defines the directory which contains the mailing list footers (one footer
-per file) which are to be tested when removing them with the options
-.B \-l
-or
-.BR \-\-ftr\-ml .
-.br
-This option is also needed if you do not want signature lengths to be
-counted wrong or fullquotes get undetected when a mailing list footer is
-appended at the bottom of the message (especially when using
-.B "\-S"
-or
-.BR "\-t" ).
-.TP
-.B "\-l"
-"list signature":
-Hides "footers" (signatures) from mailing lists. Footer detection works like the
-.B "\-a"
-option.
-.sp
-.IR NOTE :
-This requires a directory with footer files to be given with option
-.BR "\-L" =DIRECTORY.
-.B \-l
-is not needed if
-.B \-\-ftr\-ml
-is specified.
-.TP
-.B "\-\-lax\-security"
-Allow insecure writing method. DO NOT USE UNLESS YOU REALLY KNOW WHAT
-YOU ARE DOING. (This ugly workaround is needed for some early mutt versions
-and should NEVER be used as a default, otherwise it will probably turn into
-a security issue.)
-.TP
.BR "\-\-locale" =LOCALE
-"locale to use":
-Here you can specify which locale to use. Right now this option is only
-used when
-.I "\-Mmutt"
+Specify which locale to use for correct parsing of your MUA's formatting
+of the displayed message (usually it is the locale your MUA uses). Right
+now this option is only used when
+.IR "\-Mmutt" " or"
+.I "\-Mmutt\-kz"
is specified, but this may change in future. You need the Perl module
.I "Locale::gettext"
for this feature.
.sp
.IR NOTE :
If you use
-.B mutt
+.BR mutt ,
+.B mutt-kz
or
.B gnupg
with locales, t-prot will only work correctly if you specify the corresponding
with matching
.B gnupg
and
-.B mutt
+.BR mutt " /"
+.B "mutt\-kz"
versions. T-prot detects
.B gnupg
and
-.B mutt
+.BR mutt " /"
+.B "mutt\-kz"
locales of the recent stable versions of those programs, earlier versions
-might not work well with a recent version of t-prot. There are patches available
-to make t-prot fit into environments with some other
-.B mutt
-and
-.B gnupg
-versions.
+might not work well with a recent version of t-prot.
.TP
-.BR "\-M, \-\-mua" =MUA
+.BR "\-M, \-\-mua" MUA
"mail user agent":
Turn on special treatment for some mail user agents. (Right now only
.BR mutt (1)
-is supported, but more might be added in future.)
+and
+.BR "mutt\-kz" (1)
+are supported, but more might be added in future.)
.IR Caveat :
If your MUA is supported by this feature you must ensure t-prot makes
use of it when called from within your MUA to work as desired.
and some header lines...)
.TP
.B "\-\-ms\-smart"
-Burn CPU cycles trying to be smart with MS style TOFU.
+Burn CPU cycles trying to be smart with MS style TOFU: If there are PGP
+signed parts inside the TOFU, the text still might conceal other message
+parts and therefore should not be deleted.
.sp
Please note that this is probably just a waste of time because most
MS Outlook users who do produce this kind of TOFU won't care about
.BR know " the sender tries to write legible messages)."
.sp
Requires
-.BR "\-Mmutt" " and"
+.BR "\-Mmutt" " /"
+.BR "\-Mmutt\-kz" " and"
.BR "\-m" .
.TP
-.BR "\-\-max\-lines" =x
-Maximum number of lines a message may count (with headers). If the message
-is longer than x lines, the message will not be processed but printed
-unmodified. Exit status will be EX_DATAERR except when called with -Mmutt.
-.TP
-.BR "\-o" =FILE
-"output file":
-Define the file to be written *to*; the default output is to STDOUT.
-.sp
-If "NONE" is specified as file name, there will be no output at all (useful
-if all you need is t-prot's exit code). Use something like "./NONE" if you
-really want to write to a file of this name.
-.TP
-.BR "\-p" [=ADDRESS]
-"picky delivery":
-If we really find some TOFU, abort with exit code
-.IR EX_UNAVAILABLE .
-Otherwise redirect the message to ADDRESS if given.
-.sp
-Intended for use from within mail delivery agents (MDAs) or mail transport
-agents (MTAs), or even from with INN, so the message bounces if TOFU is
-detected, and does not get on *your* nerves. :)
-.sp
-As an example for usage with
-.BR sendmail ,
-put this line into your alias file and invoke
-.BR newaliases :
-.sp
-notofu: |"/usr/local/bin/t\-prot \-mt \-p=user@mydomain"
-.sp
-This will bounce messages for <notofu@domainname> if any TOFU is detected
-inside the message, and deliver it to <user@mydomain> otherwise.
-.I Note
-that TOFU is only detected if you specify
-.B "\-t"
-respectively
-.BR "\-m" .
-.sp
-.B PLEASE be careful not to bounce messages to mailing lists!
-.TP
-.BR "\-P" =MESSAGE
-"user defined bounce message for picky delivery":
-You may specify your own bounce message to be returned when we try to deliver
-an email and bounce it because there is TOFU inside.
-.TP
.B \-\-pgp\-move
-Move PGP verification output to bottom; requires
-.BR "\-Mmutt" .
+Move PGP and SSL verification output to bottom; requires
+.BR "\-Mmutt" " /"
+.BR "\-Mmutt\-kz" .
.TP
.B \-\-pgp\-move\-vrf
-Move PGP verification outout to bottom only if verification shows a good signature
-and the signature could be verified as authentic (using a trust path). If there is
-any problem with the signature, the PGP output should not be moved so the user is
-more likely to notice. Requires
-.BR "\-Mmutt" .
+Move PGP and SSL verification output to bottom only if verification shows a
+good signature and the signature could be verified as authentic (using a
+trust path). If there is any problem with the signature, the PGP output
+should not be moved so the user is more likely to notice. Requires
+.BR "\-Mmutt" " /"
+.BR "\-Mmutt\-kz" .
.sp
.IR NOTE :
If gpg is terminated before finished (e.g. hitting Ctrl-C, or using
.TP
.B \-\-pgp\-short
Hide non-relevant PGP key uids; requires
-.BR "\-Mmutt" .
+.BR "\-Mmutt" " /"
+.BR "\-Mmutt\-kz" .
.TP
.B "\-r"
"rip header off":
Hides all mail header lines.
.TP
-.BR "\-S" [=n]
-"supression of overlong signatures":
+.B "\-\-reply"
+Subject lines with multiple reply prefixes (Re: and translations into other
+languages) get squeezed to only one prefix.
+.TP
+.BR "\-S" "[n]"
+"suppression of overlong signatures":
Signatures are to be n lines (not including the one containing dash-dash-space)
or less. If there are more, it is probably not that spirited after all.
So with this option you trade it for a
Hides signatures, i.e. all lines after a "signature dashes" line,
i.e. a line with three characters: dash-dash-space (no more, no less).
.TP
+.B "\-\-sani"
+Sanitize headers "To:", "From:" and "Subject:": Quoted-printable gets
+fixed to the corresponding chars. German Umlauts are translated to their
+"ae", "oe", "ue" pendants.
+.br
+Useful e.g. for searching by subject within MUAs like Berkeley mailx.
+.TP
.BR "\-\-sigsmax" [=n]
"maximum number of tolerated signatures":
Here you can define how many signatures you accept to be treated as such.
.TP
.B "\-t"
"TOFU deletion":
-Hides "traditional style" TOFU, where each line begins with an
-indent string like "> ".
-.br
-(You may edit the indent pattern in the script itself to suit your needs,
-but it is surely
-.I not
-recommended at all.)
+Hides "traditional style" TOFU, where each line begins with the
+indent string ">".
.TP
.B "\-w"
"whitespace deletion":
Hides trailing whitespace (sequences of space and tab).
CAVEAT: This may lead to interesting effects with crossposts
between mailing lists or with undetected signature attempts.
+.SH DETECTION OPTIONS
+.TP
+.BR "\-P" " MESSAGE"
+"user defined bounce message for picky delivery":
+You may specify your own bounce message to be returned when we try to deliver
+an email and bounce it because there is TOFU inside. See
+.BR "\-p" .
+.TP
+.BR "\-p" " [ADDRESS]"
+"picky delivery":
+If we really find some TOFU, abort with exit code
+.IR EX_UNAVAILABLE .
+Otherwise redirect the message to ADDRESS if given.
+.sp
+Intended for use from within mail delivery agents (MDAs) or mail transport
+agents (MTAs), or even from within INN, so the message bounces if TOFU is
+detected, and does not get on *your* nerves. :)
+.sp
+As an example for usage with
+.BR sendmail ,
+put this line into your alias file and invoke
+.BR newaliases :
+.sp
+notofu: |"/usr/local/bin/t\-prot \-mt \-p=user@mydomain"
+.sp
+This will bounce messages for <notofu@domainname> if any TOFU is detected
+inside the message, and deliver it to <user@mydomain> otherwise.
+.I Note
+that TOFU is only detected if you specify
+.B "\-t"
+respectively
+.BR "\-m" .
+.sp
+.B PLEASE be careful not to bounce messages to mailing lists!
+.TP
+.BR "\-\-check" [=FLAGS]
+Run checks. If successful, print an error message and quit with
+an appropriate exit code. Useful e.g. for rejecting messages from
+within INN2.
+.IP
+Flags are separated by commas (no whitespaces), and can be the
+following (right now just one flag):
+.IP
+.IR ratio [=n]
+.br
+If the quoting ratio is n or more, the message is rejected. Must be
+between 0 and 1, or else it is entirely disabled. Default is 0.75
+(i.e., 75% of the message lines are quotes).
+.TP
+.B "\-d, \-\-debug"
+Print envelope info to syslog when bouncing TOFU contaminated email.
+Default syslog facility is mail.debug. Requires
+.BR \-p .
+.SH OTHER OPTIONS
+.TP
+.B "\-h, \-\-help"
+Displays a short help text with a summary on all options, and exits.
.TP
.B "\-v, \-\-version"
-Prints the current version number and release date, and exits.
+Prints the current version number and exits.
.SH ENVIRONMENT
The environment variables
.IR LC_ALL ,
.IR LC_MESSAGES ,
and
.I LANG
-are read and respected when interpreting output by mutt or gnupg
+are read and respected when interpreting output by mutt / mutt\-kz or gnupg
(unless they are overruled by the \-\-locale option). T-prot's own
output is English regardless of any locale setting.
.SH EXIT STATUS
All PGP related options are eating up lots of CPU time. Try to avoid them
on unsigned and unencrypted messages.
.PP
-When calling t-prot from within mutt, you might use mutt's folder-hook
-and message-hook facilities to turn options on only when needed, e.g. to
-set up a different footer directory for each mailing list folder.
+When calling t-prot from within mutt (or mutt\-kz), you might use mutt's
+folder-hook and message-hook facilities to turn options on only when
+needed, e.g. to set up a different footer directory for each mailing list
+folder.
.SH TROUBLESHOOTING
.TP
.IR Q :
.PP
.TP
.IR Q :
-I use the options \-l and \-L to supress mailing list footers when
+I use the options \-l and \-L to suppress mailing list footers when
displaying messages in
.BR mutt (1).
This does work sometimes, but sometimes it does not: the footer is not
All of the documentation and software included in the t-prot releases
is copyrighted by Jochen Striepe (except when explicitly stated otherwise).
.PP
-Copyright \(co 2001-2010 Jochen Striepe. All rights reserved.
+Copyright \(co 2001-2015 Jochen Striepe. All rights reserved.
.PP
Redistribution and use, with or without modification, are permitted
provided that the following conditions are met:
See the TODO file for more information.
.SH "SEE ALSO"
.BR mutt (1),
+.BR mutt\-kz (1),
.BR muttrc (5)
and the part about "display_filter",
.BR perl (1),
.BR aliases (5),
.sp
-RFCs 2045-2049 and 5322,
+RFCs 2045-2049, 3676 and 5322,
.sp
+.I http://freshmeat.net/articles/t\-prot/
+(a nice, solid introduction),
+.br
.I http://got.to/quote/
(German language),
.br
projects / pkg / t-prot.git / blobdiff