Cryptographic Token Interface Standard

PKCS#11


Object management functions

Cryptoki provides the following functions for managing objects. Additional functions provided specifically for managing key objects are described in Section 11.14.

C_CreateObject

CK_RV  C_CreateObject( CK_SESSION_HANDLE hSession, CK_ATTRIBUTE_PTR pTemplate, CK_ULONG ulCount, CK_OBJECT_HANDLE_PTR phObject);

C_CreateObject creates a new object.

Parameters:
hSession is the session's handle;
pTemplate points to the object's template;
ulCount is the number of attributes in the template;
phObject points to the location that receives the new object's handle.
If a call to C_CreateObject cannot support the precise template supplied to it, it will fail and return without creating any object.

If C_CreateObject is used to create a key object, the key object will have its CKA_LOCAL attribute set to FALSE.

Only session objects can be created during a read-only session. Only public objects can be created unless the normal user is logged in.

Returns:
CKR_ATTRIBUTE_READ_ONLY, CKR_ATTRIBUTE_TYPE_INVALID, CKR_ATTRIBUTE_VALUE_INVALID, CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_OK, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID, CKR_SESSION_READ_ONLY, CKR_TEMPLATE_INCOMPLETE, CKR_TEMPLATE_INCONSISTENT, CKR_TOKEN_WRITE_PROTECTED, CKR_USER_NOT_LOGGED_IN, CKR_ARGUMENTS_BAD.
Example:

CK_SESSION_HANDLE hSession;
CK_OBJECT_HANDLE
hData,
hCertificate,
hKey;
CK_OBJECT_CLASS
dataClass = CKO_DATA,
certificateClass = CKO_CERTIFICATE,
keyClass = CKO_PUBLIC_KEY;
CK_KEY_TYPE keyType = CKK_RSA;
CK_CHAR application[] = {"My Application"};
CK_BYTE dataValue[] = {...};
CK_BYTE subject[] = {...};
CK_BYTE id[] = {...};
CK_BYTE certificateValue[] = {...};
CK_BYTE modulus[] = {...};
CK_BYTE exponent[] = {...};
CK_BYTE true = TRUE;
CK_ATTRIBUTE dataTemplate[] = {
{CKA_CLASS, &dataClass, sizeof(dataClass)},
{CKA_TOKEN, &true, sizeof(true)},
{CKA_APPLICATION, application, sizeof(application)},
{CKA_VALUE, dataValue, sizeof(dataValue)}
};
CK_ATTRIBUTE certificateTemplate[] = {
{CKA_CLASS, &certificateClass, sizeof(certificateClass)},
{CKA_TOKEN, &true, sizeof(true)},
{CKA_SUBJECT, subject, sizeof(subject)},
{CKA_ID, id, sizeof(id)},
{CKA_VALUE, certificateValue, sizeof(certificateValue)}
};
CK_ATTRIBUTE keyTemplate[] = {
{CKA_CLASS, &keyClass, sizeof(keyClass)},
{CKA_KEY_TYPE, &keyType, sizeof(keyType)},
{CKA_WRAP, &true, sizeof(true)},
{CKA_MODULUS, modulus, sizeof(modulus)},
{CKA_PUBLIC_EXPONENT, exponent, sizeof(exponent)}
};
CK_RV rv;
.
.
.
/* Create a data object */
rv = C_CreateObject(hSession, &dataTemplate, 4, &hData);
if (rv == CKR_OK) {
.
.
.
}
/* Create a certificate object */
rv = C_CreateObject(
hSession, &certificateTemplate, 5, &hCertificate);
if (rv == CKR_OK) {
.
.
.
}
/* Create an RSA public key object */
rv = C_CreateObject(hSession, &keyTemplate, 5, &hKey);
if (rv == CKR_OK) {
.
.
.
}

C_CopyObject

CK_RV  C_CopyObject( CK_SESSION_HANDLE hSession, CK_OBJECT_HANDLE hObject, CK_ATTRIBUTE_PTR pTemplate, CK_ULONG ulCount, CK_OBJECT_HANDLE_PTR phNewObject);

C_CopyObject copies an object, creating a new object for the copy.

Parameters:
hSession is the session's handle;
hObject is the object's handle;
pTemplate points to the template for the new object;
ulCount is the number of attributes in the template;
phNewObject points to the location that receives the handle for the copy of the object.
The template may specify new values for any attributes of the object that can ordinarily be modified (e.g., in the course of copying a secret key, a key's CKA_EXTRACTABLE attribute may be changed from TRUE to FALSE, but not the other way around. If this change is made, the new key's CKA_NEVER_EXTRACTABLE attribute will have the value FALSE. Similarly, the template may specify that the new key's CKA_SENSITIVE attribute be TRUE; the new key will have the same value for its CKA_ALWAYS_SENSITIVE attribute as the original key). It may also specify new values of the CKA_TOKEN and CKA_PRIVATE attributes (e.g., to copy a session object to a token object). If the template specifies a value of an attribute which is incompatible with other existing attributes of the object, the call fails with the return code CKR_TEMPLATE_INCONSISTENT.

If a call to C_CopyObject cannot support the precise template supplied to it, it will fail and return without creating any object.

Only session objects can be created during a read-only session. Only public objects can be created unless the normal user is logged in.

Returns:
CKR_ATTRIBUTE_READ_ONLY, CKR_ATTRIBUTE_TYPE_INVALID, CKR_ATTRIBUTE_VALUE_INVALID, CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_OBJECT_HANDLE_INVALID, CKR_OK, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID, CKR_SESSION_READ_ONLY, CKR_TEMPLATE_INCONSISTENT, CKR_TOKEN_WRITE_PROTECTED, CKR_USER_NOT_LOGGED_IN, CKR_ARGUMENTS_BAD.
Example:

CK_SESSION_HANDLE hSession;
CK_OBJECT_HANDLE hKey, hNewKey;
CK_OBJECT_CLASS keyClass = CKO_SECRET_KEY;
CK_KEY_TYPE keyType = CKK_DES;
CK_BYTE id[] = {...};
CK_BYTE keyValue[] = {...};
CK_BYTE false = FALSE;
CK_BYTE true = TRUE;
CK_ATTRIBUTE keyTemplate[] = {
{CKA_CLASS, &keyClass, sizeof(keyClass)},
{CKA_KEY_TYPE, &keyType, sizeof(keyType)},
{CKA_TOKEN, &false, sizeof(false)},
{CKA_ID, id, sizeof(id)},
{CKA_VALUE, keyValue, sizeof(keyValue)}
};
CK_ATTRIBUTE copyTemplate[] = {
{CKA_TOKEN, &true, sizeof(true)}
};
CK_RV rv;
.
.
.
/* Create a DES secret key session object */
rv = C_CreateObject(hSession, &keyTemplate, 5, &hKey);
if (rv == CKR_OK) {
/* Create a copy which is a token object */
rv = C_CopyObject(hSession, hKey, &copyTemplate, 1, &hNewKey);
.
.
.
}

C_DestroyObject

CK_RV  C_DestroyObject( CK_SESSION_HANDLE hSession, CK_OBJECT_HANDLE hObject);

C_DestroyObject destroys an object.

Parameters:
hSession is the session's handle;
hObject is the object's handle.
Only session objects can be destroyed during a read-only session. Only public objects can be destroyed unless the normal user is logged in.

Returns:
CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_OBJECT_HANDLE_INVALID, CKR_OK, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID, CKR_SESSION_READ_ONLY, CKR_TOKEN_WRITE_PROTECTED.
See also:
C_GetObjectSize.

C_GetObjectSize

CK_RV  C_GetObjectSize( CK_SESSION_HANDLE hSession, CK_OBJECT_HANDLE hObject, CK_ULONG_PTR pulSize);

C_GetObjectSize gets the size of an object in bytes.

Parameters:
hSession is the session's handle;
hObject is the object's handle;
pulSize points to the location that receives the size in bytes of the object.
Cryptoki does not specify what the precise meaning of an object's size is. Intuitively, it is some measure of how much token memory the object takes up. If an application deletes (say) a private object of size S, it might be reasonable to assume that the ulFreePrivateMemory field of the token's CK_TOKEN_INFO structure increases by approximately S.

Returns:
CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_INFORMATION_SENSITIVE, CKR_OBJECT_HANDLE_INVALID, CKR_OK, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID, CKR_ARGUMENTS_BAD.
Example:

CK_SESSION_HANDLE hSession;
CK_OBJECT_HANDLE hObject;
CK_OBJECT_CLASS dataClass = CKO_DATA;
CK_CHAR application[] = {"My Application"};
CK_BYTE dataValue[] = {...};
CK_BYTE value[] = {...};
CK_BYTE true = TRUE;
CK_ATTRIBUTE template[] = {
{CKA_CLASS, &dataClass, sizeof(dataClass)},
{CKA_TOKEN, &true, sizeof(true)},
{CKA_APPLICATION, application, sizeof(application)},
{CKA_VALUE, value, sizeof(value)}
};
CK_ULONG ulSize;
CK_RV rv;
.
.
.
rv = C_CreateObject(hSession, &template, 4, &hObject);
if (rv == CKR_OK) {
rv = C_GetObjectSize(hSession, hObject, &ulSize);
if (rv != CKR_INFORMATION_SENSITIVE) {
.
.
.
}
rv = C_DestroyObject(hSession, hObject);
.
.
.
}

C_GetAttributeValue

CK_RV  C_GetAttributeValue( CK_SESSION_HANDLE hSession, CK_OBJECT_HANDLE hObject, CK_ATTRIBUTE_PTR pTemplate, CK_ULONG ulCount);

C_GetAttributeValue obtains the value of one or more attributes of an object.

Parameters:
hSession is the session's handle;
hObject is the object's handle;
pTemplate points to a template that specifies which attribute values are to be obtained, and receives the attribute values;
ulCount is the number of attributes in the template.
For each (type, pValue, ulValueLen) triple in the template, C_GetAttributeValue performs the following algorithm:

  1. If the specified attribute (i.e., the attribute specified by the type field) for the object cannot be revealed because the object is sensitive or unextractable, then the ulValueLen field in that triple is modified to hold the value -1 (i.e., when it is cast to a CK_LONG, it holds -1).

  2. Otherwise, if the specified attribute for the object is invalid (the object does not possess such an attribute), then the ulValueLen field in that triple is modified to hold the value -1.

  3. Otherwise, if the pValue field has the value NULL_PTR, then the ulValueLen field is modified to hold the exact length of the specified attribute for the object.

  4. Otherwise, if the length specified in ulValueLen is large enough to hold the value of the specified attribute for the object, then that attribute is copied into the buffer located at pValue, and the ulValueLen field is modified to hold the exact length of the attribute.

  5. Otherwise, the ulValueLen field is modified to hold the value -1.

If case 1 applies to any of the requested attributes, then the call should return the value CKR_ATTRIBUTE_SENSITIVE. If case 2 applies to any of the requested attributes, then the call should return the value CKR_ATTRIBUTE_TYPE_INVALID. If case 5 applies to any of the requested attributes, then the call should return the value CKR_BUFFER_TOO_SMALL. As usual, if more than one of these error codes is applicable, Cryptoki may return any of them. Only if none of them applies to any of the requested attributes will CKR_OK be returned.

Note that the error codes CKR_ATTRIBUTE_SENSITIVE, CKR_ATTRIBUTE_TYPE_INVALID, and CKR_BUFFER_TOO_SMALL do not denote true errors for C_GetAttributeValue. If a call to C_GetAttributeValue returns any of these three values, then the call must nonetheless have processed every attribute in the template supplied to C_GetAttributeValue. Each attribute in the template whose value can be returned by the call to C_GetAttributeValue will be returned by the call to C_GetAttributeValue.

Returns:
CKR_ATTRIBUTE_SENSITIVE, CKR_ATTRIBUTE_TYPE_INVALID, CKR_BUFFER_TOO_SMALL, CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_OBJECT_HANDLE_INVALID, CKR_OK, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID, CKR_ARGUMENTS_BAD.
Example:

CK_SESSION_HANDLE hSession;
CK_OBJECT_HANDLE hObject;
CK_BYTE_PTR pModulus, pExponent;
CK_ATTRIBUTE template[] = {
{CKA_MODULUS, NULL_PTR, 0},
{CKA_PUBLIC_EXPONENT, NULL_PTR, 0}
};
CK_RV rv;
.
.
.
rv = C_GetAttributeValue(hSession, hObject, &template, 2);
if (rv == CKR_OK) {
pModulus = (CK_BYTE_PTR) malloc(template[0].ulValueLen);
template[0].pValue = pModulus;
/* template[0].ulValueLen was set by C_GetAttributeValue */
pExponent = (CK_BYTE_PTR) malloc(template[1].ulValueLen);
template[1].pValue = pExponent;
/* template[1].ulValueLen was set by C_GetAttributeValue */
rv = C_GetAttributeValue(hSession, hObject, &template, 2);
if (rv == CKR_OK) {
.
.
.
}
free(pModulus);
free(pExponent);
}

C_SetAttributeValue

CK_RV  C_SetAttributeValue( CK_SESSION_HANDLE hSession, CK_OBJECT_HANDLE hObject, CK_ATTRIBUTE_PTR pTemplate, CK_ULONG ulCount);

C_SetAttributeValue modifies the value of one or more attributes of an object.

Parameters:
hSession is the session's handle;
hObject is the object's handle;
pTemplate points to a template that specifies which attribute values are to be modified and their new values;
ulCount is the number of attributes in the template.
Only session objects can be modified during a read-only session.

The template may specify new values for any attributes of the object that can be modified. If the template specifies a value of an attribute which is incompatible with other existing attributes of the object, the call fails with the return code CKR_TEMPLATE_INCONSISTENT.

Not all attributes can be modified; see Section 9.7 for more details.

Returns:
CKR_ATTRIBUTE_READ_ONLY, CKR_ATTRIBUTE_TYPE_INVALID, CKR_ATTRIBUTE_VALUE_INVALID, CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_OBJECT_HANDLE_INVALID, CKR_OK, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID, CKR_SESSION_READ_ONLY, CKR_TEMPLATE_INCONSISTENT, CKR_TOKEN_WRITE_PROTECTED, CKR_ARGUMENTS_BAD, CKR_USER_NOT_LOGGED_IN.
Example:

CK_SESSION_HANDLE hSession;
CK_OBJECT_HANDLE hObject;
CK_UTF8CHAR label[] = {"New label"};
CK_ATTRIBUTE template[] = {
CKA_LABEL, label, sizeof(label)-1
};
CK_RV rv;
.
.
.
rv = C_SetAttributeValue(hSession, hObject, &template, 1);
if (rv == CKR_OK) {
.
.
.
}

C_FindObjectsInit

CK_RV  C_FindObjectsInit( CK_SESSION_HANDLE hSession, CK_ATTRIBUTE_PTR pTemplate, CK_ULONG ulCount);

C_FindObjectsInit initializes a search for token and session objects that match a template.

Parameters:
hSession is the session's handle;
pTemplate points to a search template that specifies the attribute values to match;
ulCount is the number of attributes in the search template. The matching criterion is an exact byte-for-byte match with all attributes in the template. To find all objects, set ulCount to 0.
After calling C_FindObjectsInit, the application may call C_FindObjects one or more times to obtain handles for objects matching the template, and then eventually call C_FindObjectsFinal to finish the active search operation. At most one search operation may be active at a given time in a given session.

The object search operation will only find objects that the session can view. For example, an object search in an "R/W Public Session" will not find any private objects (even if one of the attributes in the search template specifies that the search is for private objects).

If a search operation is active, and objects are created or destroyed which fit the search template for the active search operation, then those objects may or may not be found by the search operation. Note that this means that, under these circumstances, the search operation may return invalid object handles.

Even though C_FindObjectsInit can return the values CKR_ATTRIBUTE_TYPE_INVALID and CKR_ATTRIBUTE_VALUE_INVALID, it is not required to. For example, if it is given a search template with nonexistent attributes in it, it can return CKR_ATTRIBUTE_TYPE_INVALID, or it can initialize a search operation which will match no objects and return CKR_OK.

Returns:
CKR_ATTRIBUTE_TYPE_INVALID, CKR_ATTRIBUTE_VALUE_INVALID, CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_OK, CKR_OPERATION_ACTIVE, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID, CKR_ARGUMENTS_BAD.
See also:
C_FindObjectsFinal.

C_FindObjects

CK_RV  C_FindObjects( CK_SESSION_HANDLE hSession, CK_OBJECT_HANDLE_PTR phObject, CK_ULONG ulMaxObjectCount, CK_ULONG_PTR pulObjectCount);

C_FindObjects continues a search for token and session objects that match a template, obtaining additional object handles.

Parameters:
hSession is the session's handle;
phObject points to the location that receives the list (array) of additional object handles;
ulMaxObjectCount is the maximum number of object handles to be returned;
pulObjectCount points to the location that receives the actual number of object handles returned.
If there are no more objects matching the template, then the location that pulObjectCount points to receives the value 0.

The search must have been initialized with C_FindObjectsInit.

Returns:
CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_OK, CKR_OPERATION_NOT_INITIALIZED, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID, CKR_ARGUMENTS_BAD.
See also:
C_FindObjectsFinal.

C_FindObjectsFinal

CK_RV  C_FindObjectsFinal( CK_SESSION_HANDLE hSession);

C_FindObjectsFinal terminates a search for token and session objects.

Parameters:
hSession is the session's handle.
Returns:
CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_OK, CKR_OPERATION_NOT_INITIALIZED, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID.
Example:

CK_SESSION_HANDLE hSession;
CK_OBJECT_HANDLE hObject;
CK_ULONG ulObjectCount;
CK_RV rv;
.
.
.
rv = C_FindObjectsInit(hSession, NULL_PTR, 0);
assert(rv == CKR_OK);
while (1) {
rv = C_FindObjects(hSession, &hObject, 1, &ulObjectCount);
if (rv != CKR_OK || ulObjectCount == 0)
break;
.
.
.
}
rv = C_FindObjectsFinal(hSession);
assert(rv == CKR_OK);

RSA Security Inc. Public-Key Cryptography Standards - PKCS#11 - v210