Add entitlements support

[cfergeau]

My project (https://github.com/crc-org/vfkit) needs entitlements to be able to use the virtualization framework.

This PR reworks special slot handling in the signing code and then adds entitlements support.

[dustin-decker]

Thanks for adding this, it's a timely addition for me! Looking forward to it in the next quill release.

[dustin-decker]

This worked perfectly for my needs! Thanks again, Christophe.

[spiffcs]

Thanks @cfergeau this also worked for me! We'll get this in and release Quill =)

[spiffcs]

I'm trying to replicate a failure I'm seeing locally in CI. Apologies, I want to isolate and figure out what's wrong before merging:

On my local when checking out this branch"

--- FAIL: TestSign (3.10s)
    --- FAIL: TestSign/sign_the_syft_binary_(with_a_password) (0.00s)
        sign_test.go:219:
            	Error Trace:	/Users/hal/GolandProjects/quill/quill/sign_test.go:219
            	Error:      	Received unexpected error:
            	            	unable to parse certificate 1 of 1: x509: certificate contains duplicate extensions
            	Test:       	TestSign/sign_the_syft_binary_(with_a_password)

[spiffcs]

👋 @cfergeau I tried to push to this branch to fix the Static Analysis error, but got an authentication problem against your branch.

Here is the diff, but you can also just run make lint-fix

diff --git a/quill/sign/entitlements.go b/quill/sign/entitlements.go
index 31e0a02..4eb8d57 100644
--- a/quill/sign/entitlements.go
+++ b/quill/sign/entitlements.go
@@ -4,8 +4,9 @@ import (
        "fmt"
        "hash"

-       "github.com/anchore/quill/quill/macho"
        "github.com/go-restruct/restruct"
+
+       "github.com/anchore/quill/quill/macho"
 )

[cfergeau]

I'm trying to replicate a failure I'm seeing locally in CI. Apologies, I want to isolate and figure out what's wrong before merging:

On my local when checking out this branch"

--- FAIL: TestSign (3.10s)
    --- FAIL: TestSign/sign_the_syft_binary_(with_a_password) (0.00s)
        sign_test.go:219:
            	Error Trace:	/Users/hal/GolandProjects/quill/quill/sign_test.go:219
            	Error:      	Received unexpected error:
            	            	unable to parse certificate 1 of 1: x509: certificate contains duplicate extensions
            	Test:       	TestSign/sign_the_syft_binary_(with_a_password)

I'm seeing this issue with origin/master (+ a7d454d ), this is not new in this PR.

[cfergeau]

👋 @cfergeau I tried to push to this branch to fix the Static Analysis error, but got an authentication problem against your branch.

"allow edit by maintainers" is checked in this PR, I don't know why you could not push.
I've fixed this now, though this comes with some additional lint changes as make lint was initially not working for me.