Land rapid7#2961, get_env and get_envs Post mixin

This unbreaks the changes introduced by rapid7#2782 by introducing
get_env and get_envs for shell sessions (not just meterpreter sessions).

Author: Tod Beardsley

lib/msf/core/post/common.rb

@@ -153,4 +153,55 @@ def report_vm(vm)
     report_host(vm_data)
   end
 
+  #
+  # Returns the value of the environment variable +env+
+  #
+  def get_env(env)
+    case session.type
+    when /meterpreter/
+      return session.sys.config.getenv(env)
+    when /shell/
+      if session.platform =~ /win/
+        if env[0,1] == '%'
+          unless env[-1,1] == '%'
+            env << '%'
+          end
+        else
+          env = "%#{env}%"
+        end
+
+        return cmd_exec("echo #{env}")
+      else
+        unless env[0,1] == '$'
+          env = "$#{env}"
+        end
+
+        return cmd_exec("echo \"#{env}\"")
+      end
+    end
+
+    nil
+  end
+
+  #
+  # Returns a hash of environment variables +envs+
+  #
+  def get_envs(*envs)
+    case session.type
+    when /meterpreter/
+      return session.sys.config.getenvs(*envs)
+    when /shell/
+      result = {}
+      envs.each do |env|
+        res = get_env(env)
+        result[env] = res unless res.blank?
+      end
+
+      return result
+    end
+
+    nil
+  end
+
 end
+

test/modules/post/test/get_env.rb

@@ -0,0 +1,61 @@
+
+$:.push "test/lib" unless $:.include? "test/lib"
+require 'module_test'
+
+#load 'test/lib/module_test.rb'
+#load 'lib/rex/text.rb'
+#load 'lib/msf/core/post/common.rb'
+
+class Metasploit4 < Msf::Post
+
+  include Msf::ModuleTest::PostTest
+  include Msf::Post::Common
+
+  def initialize(info={})
+    super( update_info( info,
+        'Name'          => 'Testing Get Envs',
+        'Description'   => %q{ This module will test Post::Common get envs API methods },
+        'License'       => MSF_LICENSE,
+        'Author'        => [ 'Ben Campbell'],
+        'Platform'      => [ 'windows', 'linux', 'java', 'python' ],
+        'SessionTypes'  => [ 'meterpreter', 'shell' ]
+      ))
+  end
+
+  def test_get_env_windows
+    if session.platform =~ /win/i
+      it "should return windows path" do
+        path = get_env('WINDIR')
+        path =~ /windows/i
+      end
+
+      it "should handle % signs" do
+        path = get_env('%WINDIR%')
+        path =~ /windows/i
+      end
+    end
+  end
+
+  def test_get_env_nix
+    unless session.platform =~ /win/i
+      it "should return user" do
+        user = get_env('USER')
+        !user.blank?
+     end
+
+      it "should handle $ sign" do
+        user = get_env('$USER')
+        !user.blank?
+      end
+    end
+  end
+
+  def test_get_envs
+    it "should return multiple envs" do
+      res = get_envs('PATH','USERNAME')
+      !res['PATH'].blank? && !res['USERNAME'].blank?
+    end
+  end
+
+end
+