Cryptographic Token Interface Standard

PKCS#11

Signing and MACing functions

Cryptoki provides the following functions for signing data (for the purposes of Cryptoki, these operations also encompass message authentication codes):

C_SignInit

CK_RV  C_SignInit( CK_SESSION_HANDLE hSession, CK_MECHANISM_PTR pMechanism, CK_OBJECT_HANDLE hKey);

C_SignInit initializes a signature operation, where the signature is an appendix to the data.

Parameters:

hSession	is the session's handle;
pMechanism	points to the signature mechanism;
hKey	is the handle of the signature key.

The CKA_SIGN attribute of the signature key, which indicates whether the key supports signatures with appendix, must be TRUE.

After calling C_SignInit, the application can either call C_Sign to sign in a single part; or call C_SignUpdate one or more times, followed by C_SignFinal, to sign data in multiple parts. The signature operation is active until the application uses a call to C_Sign or C_SignFinal to actually obtain the signature. To process additional data (in single or multiple parts), the application must call C_SignInit again.

Returns:: CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_CANCELED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_KEY_FUNCTION_NOT_PERMITTED,CKR_KEY_HANDLE_INVALID, CKR_KEY_SIZE_RANGE, CKR_KEY_TYPE_INCONSISTENT, CKR_MECHANISM_INVALID, CKR_MECHANISM_PARAM_INVALID, CKR_OK, CKR_OPERATION_ACTIVE, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID, CKR_USER_NOT_LOGGED_IN, CKR_ARGUMENTS_BAD.

See also:: C_SignFinal.

C_Sign

CK_RV  C_Sign( CK_SESSION_HANDLE hSession, CK_BYTE_PTR pData, CK_ULONG ulDataLen, CK_BYTE_PTR pSignature, CK_ULONG_PTR pulSignatureLen);

C_Sign signs data in a single part, where the signature is an appendix to the data.

Parameters:

hSession	is the session's handle;
pData	points to the data;
ulDataLen	is the length of the data;
pSignature	points to the location that receives the signature;
pulSignatureLen	points to the location that holds the length of the signature.

C_Sign uses the convention described in Section 11.2 on producing output.

The signing operation must have been initialized with C_SignInit. A call to C_Sign always terminates the active signing operation unless it returns CKR_BUFFER_TOO_SMALL or is a successful call (i.e., one which returns CKR_OK) to determine the length of the buffer needed to hold the signature.

C_Sign can not be used to terminate a multi-part operation, and must be called after C_SignInit without intervening C_SignUpdate calls.

For most mechanisms, C_Sign is equivalent to a sequence of C_SignUpdate operations followed by C_SignFinal.

Returns:: CKR_BUFFER_TOO_SMALL, CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DATA_INVALID, CKR_DATA_LEN_RANGE, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_CANCELED, 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_SignFinal for an example of similar functions.

C_SignUpdate

CK_RV  C_SignUpdate( CK_SESSION_HANDLE hSession, CK_BYTE_PTR pPart, CK_ULONG ulPartLen);

C_SignUpdate continues a multiple-part signature operation, processing another data part.

Parameters:

hSession	is the session's handle, pPart points to the data part;
ulPartLen	is the length of the data part.

The signature operation must have been initialized with C_SignInit. This function may be called any number of times in succession. A call to C_SignUpdate which results in an error terminates the current signature operation.

Returns:: CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DATA_LEN_RANGE, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_CANCELED, 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_SignFinal.

C_SignFinal

CK_RV  C_SignFinal( CK_SESSION_HANDLE hSession, CK_BYTE_PTR pSignature, CK_ULONG_PTR pulSignatureLen);

C_SignFinal finishes a multiple-part signature operation, returning the signature.

Parameters:

hSession	is the session's handle;
pSignature	points to the location that receives the signature;
pulSignatureLen	points to the location that holds the length of the signature.

C_SignFinal uses the convention described in Section 11.2 on producing output.

The signing operation must have been initialized with C_SignInit. A call to C_SignFinal always terminates the active signing operation unless it returns CKR_BUFFER_TOO_SMALL or is a successful call (i.e., one which returns CKR_OK) to determine the length of the buffer needed to hold the signature.

Returns:: CKR_BUFFER_TOO_SMALL, CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DATA_LEN_RANGE, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_CANCELED, 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.

Example:

CK_SESSION_HANDLE hSession;
CK_OBJECT_HANDLE hKey;
CK_MECHANISM mechanism = {
CKM_DES_MAC, NULL_PTR, 0
};
CK_BYTE data[] = {...};
CK_BYTE mac[4];
CK_ULONG ulMacLen;
CK_RV rv;
.
.
.
rv = C_SignInit(hSession, &mechanism, hKey);
if (rv == CKR_OK) {
rv = C_SignUpdate(hSession, data, sizeof(data));
.
.
.
ulMacLen = sizeof(mac);
rv = C_SignFinal(hSession, mac, &ulMacLen);
.
.
.
}

C_SignRecoverInit

CK_RV  C_SignRecoverInit( CK_SESSION_HANDLE hSession, CK_MECHANISM_PTR pMechanism, CK_OBJECT_HANDLE hKey);

C_SignRecoverInit initializes a signature operation, where the data can be recovered from the signature.

Parameters:

hSession	is the session's handle;
pMechanism	points to the structure that specifies the signature mechanism;
hKey	is the handle of the signature key.

The CKA_SIGN_RECOVER attribute of the signature key, which indicates whether the key supports signatures where the data can be recovered from the signature, must be TRUE.

After calling C_SignRecoverInit, the application may call C_SignRecover to sign in a single part. The signature operation is active until the application uses a call to C_SignRecover to actually obtain the signature. To process additional data in a single part, the application must call C_SignRecoverInit again.

Returns:: CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_CANCELED, CKR_FUNCTION_FAILED, CKR_GENERAL_ERROR, CKR_HOST_MEMORY, CKR_KEY_FUNCTION_NOT_PERMITTED, CKR_KEY_HANDLE_INVALID, CKR_KEY_SIZE_RANGE, CKR_KEY_TYPE_INCONSISTENT, CKR_MECHANISM_INVALID, CKR_MECHANISM_PARAM_INVALID, CKR_OK, CKR_OPERATION_ACTIVE, CKR_SESSION_CLOSED, CKR_SESSION_HANDLE_INVALID, CKR_USER_NOT_LOGGED_IN, CKR_ARGUMENTS_BAD.

See also:: C_SignRecover.

C_SignRecover

CK_RV  C_SignRecover( CK_SESSION_HANDLE hSession, CK_BYTE_PTR pData, CK_ULONG ulDataLen, CK_BYTE_PTR pSignature, CK_ULONG_PTR pulSignatureLen);

C_SignRecover signs data in a single operation, where the data can be recovered from the signature.

Parameters:

hSession	is the session's handle;
pData	points to the data;
ulDataLen	is the length of the data;
pSignature	points to the location that receives the signature;
pulSignatureLen	points to the location that holds the length of the signature.

C_SignRecover uses the convention described in Section 11.2 on producing output.

The signing operation must have been initialized with C_SignRecoverInit. A call to C_SignRecover always terminates the active signing operation unless it returns CKR_BUFFER_TOO_SMALL or is a successful call (i.e., one which returns CKR_OK) to determine the length of the buffer needed to hold the signature.

Returns:: CKR_BUFFER_TOO_SMALL, CKR_CRYPTOKI_NOT_INITIALIZED, CKR_DATA_INVALID, CKR_DATA_LEN_RANGE, CKR_DEVICE_ERROR, CKR_DEVICE_MEMORY, CKR_DEVICE_REMOVED, CKR_FUNCTION_CANCELED, 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.

Example:

CK_SESSION_HANDLE hSession;
CK_OBJECT_HANDLE hKey;
CK_MECHANISM mechanism = {
CKM_RSA_9796, NULL_PTR, 0
};
CK_BYTE data[] = {...};
CK_BYTE signature[128];
CK_ULONG ulSignatureLen;
CK_RV rv;
.
.
.
rv = C_SignRecoverInit(hSession, &mechanism, hKey);
if (rv == CKR_OK) {
ulSignatureLen = sizeof(signature);
rv = C_SignRecover(
hSession, data, sizeof(data), signature, &ulSignatureLen);
if (rv == CKR_OK) {
.
.
.
}
}

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