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Project-declaredLean 4.31.0 · null

Allowed iff explicitly permitted and not denied

Cedar.Thm.allowed_iff_explicitly_permitted_and_not_denied

Plain-language statement

A request is allowed if and only if it is explicitly permitted and is not explicitly forbidden.

Exact Lean statement

theorem allowed_iff_explicitly_permitted_and_not_denied (request : Request) (entities : Entities) (policies : Policies) :
  (IsExplicitlyPermitted request entities policies ∧ ¬ IsExplicitlyForbidden request entities policies) ↔
  (isAuthorized request entities policies).decision = .allow

Formal artifact

Lean source

Canonical source
Full Lean sourceLean 4
theorem allowed_iff_explicitly_permitted_and_not_denied (request : Request) (entities : Entities) (policies : Policies) :  (IsExplicitlyPermitted request entities policies  ¬ IsExplicitlyForbidden request entities policies)   (isAuthorized request entities policies).decision = .allow:= by  apply Iff.intro  · intro h₁, h₂    unfold isAuthorized    rw [explicitly_permitted_iff_satisfying_permit] at h₁    rw [explicitly_forbidden_iff_satisfying_forbid] at h₂    simp [h₁, h₂]  · intro h₁    have h₁' : ¬ (isAuthorized request entities policies).decision = Decision.deny := by simp [h₁]    have h₂ := (mt $ forbid_trumps_permit request entities policies) h₁'    have h₃ := allowed_only_if_explicitly_permitted request entities policies h₁    exact .intro h₃ h₂
Project
Cedar Specification
License
Apache-2.0
Commit
3f093947b8ae
Source
cedar-lean/Cedar/Thm/Authorization.lean:109-123

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Related declarations

Project-declaredLean 4.31.0

Find? ext

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Source project: Cedar Specification

Person-level attribution pending.

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Project-declaredLean 4.31.0

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Plain-language statement

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Source project: Cedar Specification

Person-level attribution pending.

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Project-declaredLean 4.31.0

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Plain-language statement

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authorizationprogram verificationsemantics

Source project: Cedar Specification

Person-level attribution pending.

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