On Wed, 2016-12-28 at 11:01 +0100, Lukas Erlacher wrote:
> I haven't found any documentation that specifies this for
> spamc/spamd.
>
I don't think that passing an email to SA via spamc makes any attempt
to strip pre-existing SA headers, but there's an easy way to check:
Find any message that has already been scanned by SA and has the SA
headers in place. Use spamc to process it through SA again and examine
the message text returned by SA:
spamc <test_message | less
will do nicely. If the pre-existing SA headers were stripped, you'll
see just the expected set of SA headers in the output. If the pre-
existing headers were NOT stripped, then at least some[*] of the SA
header types will appear twice.
The latter is my experience, so long ago I wrote a bash script that
cleans out existing SA headers from spam that I'm writing rules
against:
#!/bin/bash
#
#Syntax: cleaner [file...]
#Function: Remove SA headers from example message(s)
# If a list of files is present they are processed.
# If no list is supplied, all files in data/* are processed.
#Options: none
#
function clean()
{
echo "Cleaning $1"
gawk '
BEGIN { act = "copy";
body = "no";
}
/^[A-Za-z]/ { act = "copy" }
/^X-Spam/ { act = "skip" }
/^$/ { body = "yes"; }
{
if (act == "copy" || body == "yes")
{ print }
}
' <$1 >temp.txt
mv temp.txt $1
}
if [ $# -gt 0 ]
then
for f in $*
do
clean $f
done
else
for f in data/*.txt
do
clean $f
done
fi
Some recent Linuxes have dropped 'gawk' from their command list. If
yours is one of them, replace 'gawk' with 'awk' in the script. Awk is a
very fast text processing tool, so this script is pretty rapid too.
[*] 'at least some' because if the configuration is different between
the first and subsequent scans then different sets of SA headers will
have been included each time.
Martin
