# procmail rcfile
#########################################################################
#	putfile		Small mailserver that stores files		#
#									#
#	This script has not been tested yet, it is not unlikely that it #
#	still contains bugs.						#
#									#
#	Created by S.R. van den Berg, The Netherlands			#
#########################################################################
#$Id: putfile,v 1.4 1994/08/29 16:47:16 berg Exp $

#
# This script can either be:
#	- run from the .procmailrc file.
#	- saved as /etc/procmailrcs/putfile, chown it to the owner of the
#	  archive tree, make sure that owner is either trusted or also
#	  perform a "chmod 700 /etc/procmailrcs".  Make sure that
#	  /etc/procmailrcs is owned by root.  And enter the following
#	  entry in the alias file:
# whatever: "|exec /usr/local/bin/procmail -m /etc/procmailrcs/putfile"
#

#
# Make sure PATH is something sensible (i.e. the system default might
# not do in all cases)
#

#PATH=/bin:/usr/bin:/usr/local/bin

#
# Overall "security" check.  Uncomment and change if appropriate.
# This forwards anything suspicious to postmaster.
#

#:0
#* !^From +good.person@some.address
#! -oi postmaster

#
# Actually we only need one MAILDIR setting, namely the one that changes
# directory to the root of the archive tree we're serving.  So edit the
# following to taste (beware, *NEVER* allow write access to the $HOME
# directory of the user putfile runs under, always use a subdirectory and/or
# make sure the $HOME directory *and* all files in it are read-only for
# the putfile user himself):
#

MAILDIR=/tmp
MAILDIR=$HOME/archive
MAILDIR=/the/archive/directory/tree

#
# If you have a LOGFILE, it might not be a good idea to put it inside
# the archive tree.  People could overwrite it if it is.
#

LOGFILE=../log

#
# Create a directory named $MAILDIR/default, so that any files
# without a name can be put there.
#

DEFAULT=default
LOGABSTRACT=no
UMASK=022

#
# Canonicalise filename specification into:
# Content-Disposition: attachment; filename=some/file/name
#

:0 fhw
* ^Content-Disposition:.*;[	 ]*filename=
| formail -cX Content-Disposition: -X Content-Transfer-Encoding: \
    -R Content-Disposition: Content-Disposition: | \
   sed -e "s/^Content-Disposition:.*;[	 ]*filename=[\"	 ]*\([^\"	 ;]*\)\
.*$/Content-Disposition: attachment; filename=\1/"

:0 Efhw
* ^Content-Type:.*;[	 ]*name=
| formail -cX Content-Type: -X Content-Transfer-Encoding: \
    -R Content-Type: Content-Type: | \
   sed -e "s/^Content-Type:.*;[	 ]*directory=[\"	 ]*\([^\"	 ;]*\)\
.*;[	 ]*name=[\"	 ]*\([^\"	 ;]*\).*$/\
Content-Disposition: attachment; filename=\1/\2/" \
    -e "s/^.*;[	 ]*name=[\"	 ]*\([^\"	 ;]*\).*;\
[	 ]*directory=[\"	 ]*\([^\"	 ;]*\).*$/\
Content-Disposition: attachment; filename=\2/\1/" \
    -e "s/^.*;[	 ]*name=[\"	 ]*\([^\"	 ;]*\).*$/\
Content-Disposition: attachment; filename=\1/"

:0 Efhw
* ^Subject:[	 ]*[^	 "]
| formail -cX Subject: -X Content-Transfer-Encoding: -R Subject: Subject: | \
   sed -e "s/^Subject:.*[\"	 ]\([^\"	 ][^\"	 ]*\)[\"	 ]*$/\
Content-Disposition: attachment; filename=\1/"

:0 EB
* ^^([	 ]*$)*begin [0-7][0-7][0-7]+ [^	 ]
{
       :0 bw
  file=| sed -n -e 's/^begin [0-7]*  *\([^	 ][^	 ]*\)[	 ]*$/\1/p'

  :0 fhw
  | formail -I "" -I "Content-Disposition: attachment; filename=$file" ;
}

#
# Security checks:
#	No absolute paths
#	No paths with references to the parent (..) directory in them
#	No doublequotes in the filename
#

:0
*  ^Content-Disposition: attachment; filename=
* !^Content-Disposition: attachment; filename=(/|(.+/)?\.\.(/|$))
{

  #
  # Filename seems to be secure
  #

       :0 hw
  file=| sed -n -e 's/\([:\\]\)/\\\1/g' \
	  -e '/filename=/ {s/^.*filename=\(.*\)$/\1/p;q;}'

  #
  # If you have many persons writing the same file (not a good idea to
  # start with), you could use a global lockfile.
  #

  #LOCKFILE=../putfile.lock

  #
  # Decoding and saving the file.
  #

  LOG="File: $file
"

  :0 bw
  * ^Content-Transfer-Encoding:[	 ]*base64
  | mimencode -u -b >$file

  :0 bw
  * ^Content-Transfer-Encoding:[	 ]*quoted-printable
  | mimencode -u -q >$file

  :0 bw
  * ^Content-Transfer-Encoding:[	 ]*(x-)?uuencode
  | sed -e "s:^begin [0-7]*[0-7]\([0-7]\)[0-7].*$:begin 6\14 $file:" | \
     uudecode >$file

  :0 Bbw
  * ^^([	 ]$)*begin [0-7][0-7][0-7]+ [^	 ]
  | sed -e "1,9 s:^begin [0-7]*[0-7]\([0-7]\)[0-7].*$:begin 6\14 $file:" | \
     uudecode >$file

  #
  # Anything else seems to be unencoded
  #

  :0 b
  | cat >$file
}

#
# Either no filename or an insecure path specified.
# Delivering to the default directory.
#

:0 c
$DEFAULT

LOG="File: $LASTFOLDER
"

:0
{ HOST=filed_file }