1 files changed, 108 insertions, 0 deletions
diff --git a/misc/poc/firma-0.2 b/misc/poc/firma-0.2
new file mode 100755
index 0000000..5cf85d2
--- /dev/null
+++ b/misc/poc/firma-0.2
@@ -0,0 +1,108 @@
+#!/bin/bash
+#
+# firma v0.2: simple encrypted mailing list aliases
+# feedback: rhatto@riseup.net luis@riseup.net | GPL
+#
+# list configuration is passed thru the config file,
+# where you put PARAMETER=value (whithout spaces)
+#
+# MAIL= path for mail program
+# GPG= path for gnupg binary
+# TMP= where you want the temp files
+# LISTNAME= list email
+# LISTADMIN= list administrator email addresses (space separated)
+# GPGDIR= gpg dir for the lists' keyring
+# PASSWD= passwd for the lists' keyring
+
+# eval the config file
+source $1
+
+# declare GPG variables
+GPGCOMMAND="$GPG --quiet --homedir $GPGDIR --batch --no-tty --no-use-agent --no-permission-warning"
+GPGLIST="$GPGCOMMAND --list-keys"
+GPGDECRYPT="$GPGCOMMAND --passphrase-fd 0 --decrypt"
+GPGENCRYPT="$GPGCOMMAND --passphrase-fd 0 --always-trust --encrypt --sign --armor --recipient"
+
+# declare functions
+# discard $GPGDECRYPT STDOUT and get its STDERR instead, for signature checking
+function GPGSTDERR {
+  echo "$PASSWD" | ($GPGDECRYPT --status-fd 2 $TMP.gpg 1> /dev/null) 2>&1 ;
+}
+
+# get list susbscriber addresses
+function SUBSCRIBERS {
+  $GPGLIST | sed -n "/$LISTNAME/d;/pub/p" | grep -o '<.*>' | sed -e 's/[<>]//g' ;
+}
+
+# create the temporary files and restrict their permissions
+rm -f $TMP $TMP.gpg
+touch $TMP; chmod 600 $TMP;
+touch $TMP.gpg; chmod 600 $TMP.gpg;
+
+# todo: use an array
+while read STDIN; do
+  echo $STDIN >> $TMP
+done
+
+# get the message headers
+# todo: find a better place for $FROMADD since its not part of the message headers
+FROM=$(grep -m 1 ^From: $TMP | cut -f 2 -d :)
+FROMADD=$(echo $FROMADD | if grep -q '<' ; then echo $FROMADD | grep -o '<.*>' | sed -e 's/[<>]//g' ; else echo $FROMADD ; fi)
+DATE=$(grep -m 1 ^Date: $TMP)
+SUBJECT=$(grep -m 1 ^Subject: $TMP | cut -f 2 -d :)
+
+# get the encrypted message
+sed -n '/-----BEGIN PGP MESSAGE-----/,/-----END PGP MESSAGE-----/p' $TMP >> $TMP.gpg
+
+# if signature is OK, encrypt and send it for each list subscriber
+# todo: declare a function to decrypt, re-encrypt and send the list messages
+if (GPGSTDERR | grep -q 'GOODSIG') ; then
+
+  for EMAIL in $(SUBSCRIBERS); do 
+
+    echo "$PASSWD
+    Message from: $FROM
+    Subject: $SUBJECT
+    $DATE
+
+    $(GPGSTDERR | grep 'gpg: Signature made')
+    $(GPGSTDERR | grep 'gpg: Good signature from')
+
+$(echo "$PASSWD" | $GPGDECRYPT $TMP.gpg 2> /dev/null)" | sed -e 's/=20$//' | $GPGENCRYPT $EMAIL | $MAIL -r $LISTNAME $EMAIL
+
+  done
+
+# else, if signature is BAD, email it back to sender and to list admins
+elif (GPGSTDERR | grep -q 'BADSIG') ; then
+
+    echo "$PASSWD
+    Message from: $FROM
+    Subject: [BAD SIGNATURE] $SUBJECT
+    $DATE
+
+    $(GPGSTDERR | grep 'gpg: Signature made')
+    $(GPGSTDERR | grep 'gpg: BAD signature from')
+
+$(echo "$PASSWD" | $GPGDECRYPT $TMP.gpg 2> /dev/null)" | sed -e 's/=20$//' | $GPGENCRYPT $LISTADMIN $FROMADD | $MAIL -r $LISTNAME $LISTADMIN $FROMADD
+
+# else, probably either the message was not signed or the sender is not subscribed to the list
+# email the message back to sender including a note about this
+# todo: parse STDERR to find out why the signature couldn't be checked and send more specific errors back to sender
+else
+
+    echo "
+    Message from: $FROM
+    Subject: [RETURNED MAIL] $SUBJECT
+    $DATE
+
+    [ It was not possible to process this message. Either or both
+      the message was not encrypted and/or signed, or you are not
+      subscribed to this list.  Contact the list administrator if
+      you have any questions. ]
+
+    -- 
+    firma v0.2" | $MAIL -r $LISTNAME $FROMADD
+
+fi
+ 
+rm -f $TMP $TMP.gpg