Proposal: New CKA_DESTROYABLE attribute

This defines a new boolean attribute CKA_DESTROYABLE.
Currently it is ambiguous whether CKA_MODIFIABLE objects are destroyable with C_DestroyObject.
Cheers, Stef 10.1.3 Copying objects *** Modify paragraph, adding constant The Cryptoki attributes which can be modified during the course of a C_CopyObject operation are the same as the Cryptoki attributes which are described as being modifiable, plus the four special attributes CKA_TOKEN, CKA_PRIVATE, CKA_MODIFIABLE and CKA_DESTROYABLE.
... 10.4 Storage Objects Table 21, Common Storage Object Attributes *** Add new row

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CKA_DESTROYABLE CK_BBOOL CK_TRUE if the object can be destroyed using C_DestroyObject.
Default is CK_TRUE.

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*** Modify paragraph, removing last sentence The value of the CKA_MODIFIABLE attribute determines whether or not an object is read-only.
*** Add paragraph The value of the CKA_DESTROYABLE attribute determines whether the object can be destroyed using C_DestroyObject.
11.1.6 All other Cryptoki function return values *** Add paragraph o CKR_NOT_DESTROYABLE: An attempt was made to destroy an object which is may not be destroyed.
11.7 Object management functions o C_DestroyObject *** Add paragraph Certain object may not be destroyed.
Calling C_DestroyObject on such objects will result in the CKR_NOT_DESTROYABLE error code.
An application can consult the object's CKA_DESTROYABLE attribute to determine if an object may be destroyed or not.
*** Add value Return values: ...
CKR_NOT_DESTROYABLE A. Manifest Constants *** Add constant # define CKA_NOT_DESTROYABLE 0x0000001BUL