PKCS#11
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| Cryptographic Token Interface Standard |
PKCS#11 |
Cryptoki provides the following general-purpose functions:
CK_RV C_Initialize( CK_VOID_PTR pInitArgs);
C_Initialize initializes the Cryptoki library.
| pInitArgs | either has the value NULL_PTR or points to a CK_C_INITIALIZE_ARGS structure containing information on how the library should deal with multi-threaded access. If an application will not be accessing Cryptoki through multiple threads simultaneously, it can generally supply the value NULL_PTR to C_Initialize (the consequences of supplying this value will be explained below). |
If the CKF_LIBRARY_CANT_CREATE_OS_THREADS flag in the flags field is set, that indicates that application threads which are executing calls to the Cryptoki library are not permitted to use the native operation system calls to spawn off new threads. In other words, the library's code may not create its own threads. If the library is unable to function properly under this restriction, C_Initialize should return with the value CKR_NEED_TO_CREATE_THREADS.
A call to C_Initialize specifies one of four different ways to support multi-threaded access via the value of the CKF_OS_LOCKING_OK flag in the flags field and the values of the CreateMutex, DestroyMutex, LockMutex, and UnlockMutex function pointer fields:
A call to C_Initialize with pInitArgs set to NULL_PTR is treated like a call to C_Initialize with pInitArgs pointing to a CK_C_INITIALIZE_ARGS which has the CreateMutex, DestroyMutex, LockMutex, UnlockMutex, and pReserved fields set to NULL_PTR, and has the flags field set to 0.
C_Initialize should be the first Cryptoki call made by an application, except for calls to C_GetFunctionList. What this function actually does is implementation-dependent; typically, it might cause Cryptoki to initialize its internal memory buffers, or any other resources it requires.
If several applications are using Cryptoki, each one should call C_Initialize. Every call to C_Initialize should (eventually) be succeeded by a single call to C_Finalize. See Section 6.6 for more details.
CK_RV C_Finalize( CK_VOID_PTR pReserved);
C_Finalize is called to indicate that an application is finished with the Cryptoki library. It should be the last Cryptoki call made by an application.
| pReserved | is reserved for future versions: for this version, it should be set to NULL_PTR (if C_Finalize is called with a non-NULL_PTR value for pReserved, it should return the value CKR_ARGUMENTS_BAD. |
''Despite the fact that the parameters supplied to C_Initialize can in general allow for safe multi-threaded access to a Cryptoki library, the behavior of C_Finalize is nevertheless undefined if it is called by an application while other threads of the application are making Cryptoki calls. The exception to this exceptional behavior of C_Finalize occurs when a thread calls C_Finalize while another of the application's threads is blocking on Cryptoki's C_WaitForSlotEvent function. When this happens, the blocked thread becomes unblocked and returns the value CKR_CRYPTOKI_NOT_INITIALIZED.@see C_WaitForSlotEvent for more information.''
CK_RV C_GetInfo( CK_INFO_PTR pInfo);
C_GetInfo returns general information about Cryptoki.
| pInfo | points to the location that receives the information. |
CK_INFO info; CK_RV rv; CK_C_INITIALIZE_ARGS InitArgs; InitArgs.CreateMutex = &MyCreateMutex; InitArgs.DestroyMutex = &MyDestroyMutex; InitArgs.LockMutex = &MyLockMutex; InitArgs.UnlockMutex = &MyUnlockMutex; InitArgs.flags = CKF_OS_LOCKING_OK; InitArgs.pReserved = NULL_PTR; rv = C_Initialize((CK_VOID_PTR)&InitArgs); assert(rv == CKR_OK); rv = C_GetInfo(&info); assert(rv == CKR_OK); if(info.version.major == 2) { /* Do lots of interesting cryptographic things with the token */ . . } rv = C_Finalize(NULL_PTR); assert(rv == CKR_OK);
CK_RV C_GetFunctionList( CK_FUNCTION_LIST_PTR_PTR ppFunctionList);
C_GetFunctionList obtains a pointer to the Cryptoki library's list of function pointers.
| ppFunctionList | points to a value which will receive a pointer to the library's CK_FUNCTION_LIST structure, which in turn contains function pointers for all the Cryptoki API routines in the library. The pointer thus obtained may point into memory which is owned by the Cryptoki library, and which may or may not be writable. Whether or not this is the case, no attempt should be made to write to this memory. |
CK_FUNCTION_LIST_PTR pFunctionList; CK_C_Initialize pC_Initialize; CK_RV rv; /* It's OK to call C_GetFunctionList before calling C_Initialize */ rv = C_GetFunctionList(&pFunctionList); assert(rv == CKR_OK); pC_Initialize = pFunctionList -> C_Initialize; /* Call the C_Initialize function in the library */ rv = (*pC_Initialize)(NULL_PTR);