SignFile task referenced, but not provided, in Microsoft.Build.Tasks.Core

[Zastai]

When using dotnet build, attempting to sign assemblies results in

error MSB4062: The "Microsoft.Build.Tasks.SignFile" task could not be loaded from the assembly Microsoft.Build.Tasks.Core, Version=15.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a.
Confirm that the <UsingTask> declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask.

It is declared in Microsoft.Common.tasks:

    <UsingTask TaskName="Microsoft.Build.Tasks.SignFile"                              AssemblyName="Microsoft.Build.Tasks.Core, Version=15.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" Condition="'$(MSBuildAssemblyVersion)' != ''" />

It looks like the task is only present in the .NET Framework version of the assembly, not in the standard/core version.

Oddly, the backend signing methods ARE present in the core assembly (SecurityUtilities.SignFile()), so there does not seem to be any reason to omit the task.

The task should be added to the standard/core assembly too; on non-Windows it can fail with PNSE, but on Windows it should work with dotnet build the same way it does with msbuild.

If that is not possible, it should still be added so that it can give a useful error rather than MSB4062, because that suggests user/configuration error.

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[OndrejHlavka]

We're running into the same issue.

[dsplaisted]

Moving to MSBuild. It's possible that the functionality to implement this was not available when MSBuild was originally ported to .NET Core, but is now available in more recent versions.

[j5aenz]

I am currently having this issues as well. I have tried to publish using other methods and this is the most descriptive message. so far. It does look like a compatibility issue between net5 and msbuild. i am targeting net5-windows10.0.19041.0.

[benvillalobos]

@sujitnayak is it reasonable to enable this task on .NET Core on Windows?

[sujitnayak]

Yes it should be reasonable to support this during build. For ClickOnce publish that also calls SignFile, we don't support the dotnet CLI yet.

[benvillalobos]

Team Triage: Since there are some scenarios that won't be supported, we can enable SignFile. We're open to taking a PR as this isn't high priority for us