fix/redo OLD_DHGEX compat

git-svn-id: file:///home/svn/framework3/trunk@10573 4d416f70-5f16-0410-b530-b9f4589650da

lib/net/ssh/transport/constants.rb

@@ -26,5 +26,11 @@ module Net; module SSH; module Transport
     KEXDH_INIT                = 30
     KEXDH_REPLY               = 31
 
+	 #--
+	 # Compatability flags
+	 #++
+
+	 COMPAT_OLD_DHGEX          = 0x1
+
   end
 end; end; end

lib/net/ssh/transport/kex/diffie_hellman_group_exchange_sha1.rb

@@ -35,20 +35,11 @@ module Net::SSH::Transport::Kex
       def get_parameters
         compute_need_bits
 
-		  # Do we need to use the old request?
-		  do_SSH_OLD_DHGEX = false
-		  if (data[:server_version_string] =~ /OpenSSH_2\.[0-3]/)
-			  do_SSH_OLD_DHGEX = true
-		  elsif (data[:server_version_string] =~ /OpenSSH_2\.5\.[0-2]/)
-			  do_SSH_OLD_DHGEX = true
-		  end
-
-		  if (do_SSH_OLD_DHGEX)
 		  # request the DH key parameters for the given number of bits.
+		  if connection.compat_flags & COMPAT_OLD_DHGEX
 			  buffer = Net::SSH::Buffer.from(:byte, KEXDH_GEX_REQUEST_OLD, :long,
 				  data[:need_bits])
 		  else
-			  # request the DH key parameters for the given number of bits.
 			  buffer = Net::SSH::Buffer.from(:byte, KEXDH_GEX_REQUEST, :long, MINIMUM_BITS,
 				  :long, data[:need_bits], :long, MAXIMUM_BITS)
 		  end
@@ -80,9 +71,11 @@ module Net::SSH::Transport::Kex
                               data[:client_algorithm_packet],
                               data[:server_algorithm_packet],
                               result[:key_blob]
-        response.write_long MINIMUM_BITS,
-                            data[:need_bits],
-                            MAXIMUM_BITS
+
+        response.write_long MINIMUM_BITS if not connection.compat_flags & COMPAT_OLD_DHGEX
+        response.write_long data[:need_bits]
+        response.write_long MAXIMUM_BITS if not connection.compat_flags & COMPAT_OLD_DHGEX
+
         response.write_bignum dh.p, dh.g, dh.pub_key,
                               result[:server_dh_pubkey],
                               result[:shared_secret]

lib/net/ssh/transport/session.rb

@@ -40,6 +40,9 @@ module Net; module SSH; module Transport
     # version.
     attr_reader :server_version
 
+    # Internal compatability flags (hacks/tweaks/etc)
+    attr_reader :compat_flags
+
     # The Algorithms instance used to perform key exchanges.
     attr_reader :algorithms
 
@@ -76,6 +79,8 @@ module Net; module SSH; module Transport
             }
           )
         }
+        # Tell MSF to automatically close this socket on error or completion...
+		  # This prevents resource leaks.
 		  options[:msfmodule].add_socket(@socket)
       end
 
@@ -90,6 +95,13 @@ module Net; module SSH; module Transport
 
       @server_version = ServerVersion.new(socket, logger)
 
+      # Compatability settings
+      ver = @server_version.version
+      @compat_flags = 0
+      if ver =~ /OpenSSH_2\.[0-3]/ or ver =~ /OpenSSH_2\.5\.[0-2]/
+        @compat_flags |= COMPAT_OLD_DHGEX
+      end
+
       @algorithms = Algorithms.new(self, options)
       wait { algorithms.initialized? }
     end