How to hide the value of customactiondata in logs of MSI?

Question

I have a deferred custom action which fetches a property using Customactiondata, it contains the value of password that should not be displayed in the log .

Packaging tool used: WIX

Custom action written in C++

I have tried the below workarounds nothing seems to be working.

1. Marked the property and CA name as hidden

2. Hidetarget = yes in CA definition

what needs to be done?

Code:

<CustomAction Id="CASETLOGINFORRCSERVICES" Return="check" HideTarget="yes" Execute="deferred" Impersonate="no" TerminalServerAware="no" DllEntry="SetLoginForRCServices" BinaryKey="CA_Dll" />

log:

MSI (s) (7C:CC) [18:35:39:011]: Executing op: CustomActionSchedule(Action=CASETLOGINFORRCSERVICES,ActionType=3073,Source=BinaryData,Target=SetLoginForRCServices,CustomActionData=Deps@@@151232323)
MSI (s) (7C:B0) [18:35:39:038]: Invoking remote custom action. DLL: C:\WINDOWS\Installer\MSIEB69.tmp, Entrypoint: SetLoginForRCServices

Gisele

Some good reasons to do licensing inside your application and not your setup. – Josephina

Answer 1

MsiHiddenProperties: There is a property you can set to hide property values from being written to the log: MsiHiddenProperties property (there are further links in there to more information on preventing confidential information in your MSI).

Custom Action: Setting the attribute HideTarget="yes" for the custom action will set the above property value for you. However this feature does not seem to hide any value you hard-code in the property table from the log - so if you set an actual value for the property in the property table you need to set the property itself hidden as well (you can set a value programmatically or via the GUI without setting it in the property table). Here are samples:

HideTarget="Yes":

<CustomAction Id="ReadProperyDeferred" HideTarget="yes" ... />

Property Hidden="yes":

<Property Id="MYPROPERTY" Hidden="yes" Secure="yes">Text</Property>

Samples: Sample WiX source here: https://github.com/glytzhkof/WiXDeferredModeSample.

Here is another sample for deferred mode - it uses the DTF class CustomActionData to easily send properties to deferred mode: https://github.com/glytzhkof/WiXDeferredModeSampleDTF

Remember to avoid custom actions if you can: Why is it a good idea to limit the use of custom actions in my WiX / MSI setups?

Sensitive Information: Here is an answer on preventing sensitive or unwanted information to make it into your MSI: How do I avoid distributing sensitive information in my MSI by accident?

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Code Extract: Prefer to open the above sample. However, here is a "compressed" sequence of WiX constructs needed for deferred mode custom actions retrieving data from a set-property custom action:

<Property Id="MYPROPERTY" Hidden="yes" Secure="yes">Send this text to deferred mode</Property>
<Binary Id="CustomActions" SourceFile="$(var.CustomActionSample.TargetDir)$(var.CustomActionSample.TargetName).CA.dll" />

<CustomAction Id="SetProperty" Return="check" Property="ReadProperyDeferred" Value="[MYPROPERTY]" />
<CustomAction Id="ReadProperyDeferred" HideTarget="yes" BinaryKey="CustomActions" Execute="deferred" DllEntry="TestCustomAction" />

<InstallExecuteSequence>
  <Custom Action='SetProperty' Before='InstallInitialize'></Custom>
  <Custom Action='ReadProperyDeferred' Before='InstallFinalize'></Custom>
</InstallExecuteSequence>

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Links:

• WIX execute custom action with admin privilege
• Older answer of mine on deferred mode
• How can I automate testing an MSI is installable with UAC?

Fluidize

OK, great. Please set the answer accepted. What was the exact problem? – Josephina

I followed the same exact steps from you answer and it worked , not sure what the exact problem was from my previous approach ! – Gisele

OK, the crux of it is to make sure the custom action is deferred, not impersonated (but running in system context) and that the deferred custom action name matches the property name. How you sequence things is also important (where actions run in the InstallExecuteSequence). It is honestly one of the craziest mechanisms I have ever seen in any technology. High astonishment factor. – Josephina

Could'nt agree more with you :) – Gisele

Answer 2

Add HideTarget="Yes" to the custom action.

Manutius

Hello , I have already tried this as mention in the question , sadly, does not work for me – Gisele