Unseal Capability unseals a capability with an unsealing capability, by checking the ObjectType of the capability against the Capability Value of the unsealing capability, and writes the result to the destination Capability register.
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 1 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 1 | 0 | Cm | 0 | 1 | 0 | 0 | 1 | 0 | Cn | Cd | ||||||||||||
| opc | |||||||||||||||||||||||||||||||
integer d = UInt(Cd); integer n = UInt(Cn); integer m = UInt(Cm);
| <Cd> |
Is the capability name of the destination register, encoded in the "Cd" field. |
| <Cn> |
Is the capability name of the first source register, encoded in the "Cn" field. |
| <Cm> |
Is the capability name of the second source register, encoded in the "Cm" field. |
CheckCapabilitiesEnabled(); bits(64) value = CapGetValue(C[m]); bits(64) otype = CapGetObjectType(C[n]); Capability c = CapUnseal(C[n]); if !CapCheckPermissions(C[m], CAP_PERM_GLOBAL) then c = CapClearPerms(c, CAP_PERM_GLOBAL); if CapIsTagSet(C[n]) && CapIsTagSet(C[m]) && CapIsSealed(C[n]) && !CapIsSealed(C[m]) && CapCheckPermissions(C[m], CAP_PERM_UNSEAL) && CapIsInBounds(C[m]) && otype == value then C[d] = c; else C[d] = CapWithTagClear(c);
Internal version only: isa v32.13, AdvSIMD v29.04, pseudocode morello-2022-01_rc2, capabilities morello-2022-01_rc2 ; Build timestamp: 2022-01-11T11:23
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