Only modify elevated username under specific conditions

Elevated commands can fail via winrm under certain conditions like
the machine name being changed. Detect this by checking for a known
exit code combined with known output included within stderr. If found,
attempt to re-execute the command using a machine prefixed username
if possible.

plugins/communicators/winrm/shell.rb

@@ -17,6 +17,10 @@ module VagrantPlugins
     class WinRMShell
       include Vagrant::Util::Retryable
 
+      # Exit code generated when user is invalid. Can occur
+      # after a hostname update
+      INVALID_USERID_EXITCODE = -196608
+
       # These are the exceptions that we retry because they represent
       # errors that are generally fixed from a retry and don't
       # necessarily represent immediate failure cases.
@@ -71,13 +75,22 @@ module VagrantPlugins
       def elevated(command, opts = {}, &block)
         connection.shell(:elevated) do |shell|
           shell.interactive_logon = opts[:interactive] || false
-          uname = shell.username
-          begin
-            shell.username = elevated_username
-            execute_with_rescue(shell, command, &block)
-          ensure
-            shell.username = uname
+          result = execute_with_rescue(shell, command, &block)
+          if result.exitcode == INVALID_USERID_EXITCODE && result.stderr.include?(":UserId:")
+            uname = shell.username
+            ename = elevated_username
+            if uname != ename
+              @logger.warn("elevated command failed due to username error")
+              @logger.warn("retrying command using machine prefixed username - #{ename}")
+              begin
+                shell.username = ename
+                result = execute_with_rescue(shell, command, &block)
+              ensure
+                shell.username = uname
+              end
+            end
           end
+          result
         end
       end
 
@@ -224,11 +237,8 @@ module VagrantPlugins
       end
 
       def elevated_username
-        if @elevated_username
-          return @elevated_username
-        end
         if username.include?("\\")
-          return @elevated_username = username
+          return username
         end
         computername = ""
         powershell("Write-Output $env:computername") do |type, data|
@@ -236,9 +246,9 @@ module VagrantPlugins
         end
         computername.strip!
         if computername.empty?
-          return @elevated_username = username
+          return username
         end
-        @elevated_username = "#{computername}\\#{username}"
+        "#{computername}\\#{username}"
       end
     end #WinShell class
   end

test/unit/plugins/communicators/winrm/shell_test.rb

@@ -75,10 +75,16 @@ describe VagrantPlugins::CommunicatorWinRM::WinRMShell do
   end
 
   describe ".elevated" do
+    let(:eusername) { double("elevatedusername") }
     let(:username) { double("username") }
+    let(:failed_output) { WinRM::Output.new.tap { |out|
+        out.exitcode = -196608
+        out << {stderr: "(10,8):UserId:"}
+        out << {stderr: "At line:72 char:1"}
+      } }
 
     before do
-      allow(subject).to receive(:elevated_username).and_return(username)
+      allow(subject).to receive(:elevated_username).and_return(eusername)
       allow(shell).to receive(:username).and_return(username)
       allow(shell).to receive(:username=)
     end
@@ -102,12 +108,20 @@ describe VagrantPlugins::CommunicatorWinRM::WinRMShell do
         VagrantPlugins::CommunicatorWinRM::Errors::ExecutionError)
     end
 
-    it "should use elevated username" do
-      expect(subject).to receive(:elevated_username).and_return(username)
+    it "should use elevated username and retry on username failure" do
+      expect(subject).to receive(:elevated_username).and_return(eusername)
+      expect(shell).to receive(:run).with("dir").and_return(failed_output)
       expect(shell).to receive(:run).with("dir").and_return(output)
       expect(shell).to receive(:interactive_logon=).with(false)
       expect(subject.elevated("dir").exitcode).to eq(0)
     end
+
+    it "should not retry on username failure if elevated username is the same" do
+      expect(subject).to receive(:elevated_username).and_return(username)
+      expect(shell).to receive(:run).with("dir").and_return(failed_output)
+      expect(shell).to receive(:interactive_logon=).with(false)
+      expect(subject.elevated("dir").exitcode).to eq(failed_output.exitcode)
+    end
   end
 
   describe ".cmd" do
@@ -215,8 +229,8 @@ describe VagrantPlugins::CommunicatorWinRM::WinRMShell do
       expect(subject.send(:elevated_username)).to eq("COMPUTERNAME\\#{username}")
     end
 
-    it "should only compute elevated username once" do
-      expect(subject).to receive(:powershell).once.with(/computername/).and_yield(:stdout, "COMPUTERNAME")
+    it "should compute elevated username every time" do
+      expect(subject).to receive(:powershell).twice.with(/computername/).and_yield(:stdout, "COMPUTERNAME")
       expect(subject.send(:elevated_username)).to eq("COMPUTERNAME\\#{username}")
       expect(subject.send(:elevated_username)).to eq("COMPUTERNAME\\#{username}")
     end