NAME¶

mimecheck - determine the type of the MIME encoded of an attachment
mimezip - detect the type of MIME encoded zip archive in an attachment
mimebzip - detect the type of MIME encoded bzip2 data in an attachment
mimegzip - detect the type of MIME encoded gzip data in an attachment

SYNOPSIS¶

mimecheck boundary [file]
mimezip boundary [file]
mimebzip boundary [file]
mimegzip boundary [file]

DESCRIPTION¶

The scripts mimecheck, mimezip, mimebzip, and mimegzip can be used to determine the contents of MIME encoded attachments of the type application/octet-stream. The scripts require the boundary as provided in the headers and/or bodys of mails with enclosed attachments. The scripts read from standard input if no file was provided and write out the detected MIME type to standard out.

EXAMPLE¶

A short filter rule used by procmail(1) to check for DOS executables in MIME encoded zip archives found in many attachments:

BLANK="[ 	]+"
TYPE="${BLANK}multipart/(alternative|mixed)"
:0
* $ ^Content-Type:${TYPE};(${BLANK}|$)*boundary=[\"']?[^ \"';]+
{
	BOUNDARY="${MATCH}"
	TYPE=""
	:0 B


        * $ ^Content-Transfer-Encoding:${BLANK}base64
	{
		TYPE=`mimecheck ${BOUNDARY}`
		:0
		* TYPE ?? application/x-zip
		{
			TYPE=`mimezip ${BOUNDARY}`
		}
	}
	:0
	* TYPE ?? executable.*DOS
	* TYPE ?? DOS.*executable
	/dev/null
}

there is no guarantee that this piece of a procmailrc(5) file will work.

SEE ALSO¶

procmailrc(5), file(1), sed(1), mimencode(1).

COPYRIGHT¶

2007 SuSE LINUX Products GmbH, Nuernberg, Germany,
2007 Werner Fink.

AUTHORS¶

Werner Fink <werner@suse.de>.