add an extra check for JAVA_HOME

git-svn-id: file:///home/svn/framework3/trunk@11118 4d416f70-5f16-0410-b530-b9f4589650da

lib/msf/core/exploit/java.rb

@@ -38,15 +38,20 @@ module Exploit::Java
 		end
 	end
 
-	def init_jvm(jvmoptions=nil)
+	def init_jvm(jvmoptions = nil)
 		if (not ENV['JAVA_HOME'])
-			raise RuntimeError, 'Please set JAVA_HOME'
+			raise RuntimeError, 'JAVA_HOME is not set'
+		end
+
+		toolsjar = File.join(ENV['JAVA_HOME'], "lib", "tools.jar")
+		if (not File.exists? toolsjar)
+			raise RuntimeError, 'JAVA_HOME does not point to a valid JDK installation.'
 		end
 
 		# Instantiate the JVM with a classpath pointing to the JDK tools.jar
 		# and our javatoolkit jar.
 		classpath  = File.join(Msf::Config.install_root, "data", "exploits", "msfJavaToolkit.jar")
-		classpath += ":" + File.join(ENV['JAVA_HOME'], "lib", "tools.jar")
+		classpath += ":" + toolsjar
 		classpath += ":" + datastore['ADDCLASSPATH'] if datastore['ADDCLASSPATH']
 
 		Rjb::load(classpath, jvmargs=[])