What are entitlements, and what happens when they do not match the provisioning profile?

6.1.3 · L3 · Interview

Predict first

Your app is signed with an entitlement that its provisioning profile does not allow. What happens?

// A: the entitlement is ignored
// B: the app fails to install or launch
// C: only that feature fails silently at runtime
  • A
  • B
  • C

Mental model. The entitlements are the keys listed on your signed pass. The profile is the building manager’s approved list, and the guards compare the two.

An entitlement is a signed key-value pair embedded in your app’s code signature that grants a capability the sandbox would otherwise deny: push notifications (aps-environment), app groups, keychain access groups, associated domains, iCloud, HealthKit, background modes and more. Adding a capability in Xcode edits the .entitlements file and the matching App ID setting.

The system checks them twice. At install and launch, the kernel’s code-signing enforcement verifies that the signature is valid and that every entitlement in the app is allowed by the provisioning profile that Apple signed for your team and App ID. If the app claims an entitlement the profile does not grant, it fails to install or launch (often with an unhelpful “code signature invalid” or profile error). At runtime, system services check the entitlement of the caller before serving it, so a missing keychain group or associated domain shows up as a failed API call, not a crash. Inspect what an app claims with codesign -d --entitlements :- App.app.

The kernel verifies the signed entitlements against the profile, so a mismatch stops the app from launching at all.

Common traps

  • Editing the entitlements file without updating the App ID or profile. The build may succeed, and the app is rejected at install.
  • Assuming a debug and a release build have the same entitlements. Push and associated-domain environments differ by configuration.

They might follow up with

  • How do you see why an app fails to launch from a signing problem? Device logs from amfid and the system log name the mismatched entitlement.
  • Which common entitlements need a profile change? App groups, push, associated domains, iCloud, and keychain sharing.

Related questions

  • 6.8.1 What is an app group, and what can go wrong when an app and an extension share a database?
  • 6.7.3 What does the apple-app-site-association file contain, and how does the system verify a domain?
  • 6.1.1 What is the iOS process model, and what can an app process not do?

← What is the app container, and why must you never persist an absolute…   How do privacy permissions work, and what do you do after the user… →