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capdl: fail-closed capability rights in spec - #375
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Per seL4's `maskCapRights` function (and `Arch_` variant), only caps for Endpoints, Notifications, Replies, and Frames have rights which seL4 cares about (or can be stored inside the capability). Currently, rust-seL4 does not support setting rights on Reply caps in the capDL specification, but there is a 'capReplyCanGrant' bit in the Reply capability which controls capability transfer. In case we miss more of these, or more are added, default right-less caps in the spec to being minted with `CapRights::none()`, which gives them no rights by default. For most cap types, this does not actually matter; for cap types where it does matter the `rights()` method should return `Some()` as per the implementation. Perform a similar change for mint_iospace_cap (internal helper, not exposed to users, and it does not care about the rights), and document `CapRights::all` for copying to the notification bound to an IRQ (which does need Send/Write permissions). Signed-off-by: Julia Vassiliki <julia.vassiliki@unsw.edu.au>
Only the 'Grant' bit of the Rights means anything for the Reply Cap, which controls 'capReplyCanGrant' bit. Signed-off-by: Julia Vassiliki <julia.vassiliki@unsw.edu.au>
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Per seL4's
maskCapRightsfunction (andArch_variant), only capsfor Endpoints, Notifications, Replies, and Frames have rights
which seL4 cares about (or can be stored inside the capability).
Currently, rust-seL4 does not support setting rights on Reply caps
in the capDL specification, but there is a 'capReplyCanGrant' bit
in the Reply capability which controls capability transfer.
In case we miss more of these, or more are added, default right-less
caps in the spec to being minted with
CapRights::none(), whichgives them no rights by default. For most cap types, this does not
actually matter; for cap types where it does matter the
rights()method should return
Some()as per the implementation.Perform a similar change for mint_iospace_cap (internal helper,
not exposed to users, and it does not care about the rights),
and document
CapRights::allfor copying to the notification boundto an IRQ (which does need Send/Write permissions).
Then fix the reply cap rights thing.