C_UnwrapKey() public method

Unwraps (i.e. decrypts) a wrapped key, creating a new private key or secret key object
public C_UnwrapKey ( uint session, CK_MECHANISM &mechanism, uint unwrappingKey, byte wrappedKey, uint wrappedKeyLen, CK_ATTRIBUTE template, uint attributeCount, uint &key ) : CKR
session uint The session's handle
mechanism CK_MECHANISM Unwrapping mechanism
unwrappingKey uint The handle of the unwrapping key
wrappedKey byte Wrapped key
wrappedKeyLen uint The length of the wrapped key
template CK_ATTRIBUTE The template for the new key
attributeCount uint The number of attributes in the template
key uint Location that receives the handle of the unwrapped key
return CKR
        public void _01_BasicWrapAndUnwrapKeyTest()
        {
            if (Platform.UnmanagedLongSize != 4 || Platform.StructPackingSize != 0)
                Assert.Inconclusive("Test cannot be executed on this platform");

            CKR rv = CKR.CKR_OK;
            
            using (Pkcs11 pkcs11 = new Pkcs11(Settings.Pkcs11LibraryPath))
            {
                rv = pkcs11.C_Initialize(Settings.InitArgs40);
                if ((rv != CKR.CKR_OK) && (rv != CKR.CKR_CRYPTOKI_ALREADY_INITIALIZED))
                    Assert.Fail(rv.ToString());
                
                // Find first slot with token present
                uint slotId = Helpers.GetUsableSlot(pkcs11);
                
                uint session = CK.CK_INVALID_HANDLE;
                rv = pkcs11.C_OpenSession(slotId, (CKF.CKF_SERIAL_SESSION | CKF.CKF_RW_SESSION), IntPtr.Zero, IntPtr.Zero, ref session);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());
                
                // Login as normal user
                rv = pkcs11.C_Login(session, CKU.CKU_USER, Settings.NormalUserPinArray, Convert.ToUInt32(Settings.NormalUserPinArray.Length));
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());
                
                // Generate asymetric key pair
                uint pubKeyId = CK.CK_INVALID_HANDLE;
                uint privKeyId = CK.CK_INVALID_HANDLE;
                rv = Helpers.GenerateKeyPair(pkcs11, session, ref pubKeyId, ref privKeyId);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());
                
                // Generate symetric key
                uint keyId = CK.CK_INVALID_HANDLE;
                rv = Helpers.GenerateKey(pkcs11, session, ref keyId);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                // Specify wrapping mechanism (needs no parameter => no unamanaged memory is needed)
                CK_MECHANISM mechanism = CkmUtils.CreateMechanism(CKM.CKM_RSA_PKCS);

                // Get length of wrapped key in first call
                uint wrappedKeyLen = 0;
                rv = pkcs11.C_WrapKey(session, ref mechanism, pubKeyId, keyId, null, ref wrappedKeyLen);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                Assert.IsTrue(wrappedKeyLen > 0);
                
                // Allocate array for wrapped key
                byte[] wrappedKey = new byte[wrappedKeyLen];

                // Get wrapped key in second call
                rv = pkcs11.C_WrapKey(session, ref mechanism, pubKeyId, keyId, wrappedKey, ref wrappedKeyLen);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                // Do something interesting with wrapped key

                // Define attributes for unwrapped key
                CK_ATTRIBUTE[] template = new CK_ATTRIBUTE[6];
                template[0] = CkaUtils.CreateAttribute(CKA.CKA_CLASS, CKO.CKO_SECRET_KEY);
                template[1] = CkaUtils.CreateAttribute(CKA.CKA_KEY_TYPE, CKK.CKK_DES3);
                template[2] = CkaUtils.CreateAttribute(CKA.CKA_ENCRYPT, true);
                template[3] = CkaUtils.CreateAttribute(CKA.CKA_DECRYPT, true);
                template[4] = CkaUtils.CreateAttribute(CKA.CKA_DERIVE, true);
                template[5] = CkaUtils.CreateAttribute(CKA.CKA_EXTRACTABLE, true);

                // Unwrap key
                uint unwrappedKeyId = 0;
                rv = pkcs11.C_UnwrapKey(session, ref mechanism, privKeyId, wrappedKey, wrappedKeyLen, template, Convert.ToUInt32(template.Length), ref unwrappedKeyId);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                // Do something interesting with unwrapped key

                rv = pkcs11.C_DestroyObject(session, privKeyId);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());
                
                rv = pkcs11.C_DestroyObject(session, pubKeyId);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());
                
                rv = pkcs11.C_DestroyObject(session, keyId);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());
                
                rv = pkcs11.C_Logout(session);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());
                
                rv = pkcs11.C_CloseSession(session);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());
                
                rv = pkcs11.C_Finalize(IntPtr.Zero);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());
            }
        }