Net.Pkcs11Interop.LowLevelAPI40.Pkcs11.C_FindObjects C# (CSharp) Method

        public CKR C_FindObjects(uint session, uint[] objectId, uint maxObjectCount, ref uint objectCount)
        {
            if (this._disposed)
                throw new ObjectDisposedException(this.GetType().FullName);

            uint rv = _delegates.C_FindObjects(session, objectId, maxObjectCount, ref objectCount);
            return (CKR)rv;
        }

        /// <summary>
        /// Creates the PKCS#1 v1.5 RSA signature with SHA-1 mechanism
        /// </summary>
        /// <param name="data">Data that should be signed</param>
        /// <param name="uri">PKCS#11 URI identifying PKCS#11 library, token and private key</param>
        /// <returns>PKCS#1 v1.5 RSA signature</returns>
        private byte[] SignData(byte[] data, string uri)
        {
            // Verify input parameters
            if (data == null)
                throw new ArgumentNullException("data");

            if (string.IsNullOrEmpty(uri))
                throw new ArgumentNullException("uri");

            // Parse PKCS#11 URI
            Pkcs11Uri pkcs11Uri = new Pkcs11Uri(uri);

            // Verify that URI contains all information required to perform this operation
            if (pkcs11Uri.ModulePath == null)
                throw new Exception("PKCS#11 URI does not specify PKCS#11 library");

            if (pkcs11Uri.PinValue == null)
                throw new Exception("PKCS#11 URI does not specify PIN");

            if (!pkcs11Uri.DefinesObject || pkcs11Uri.Type != CKO.CKO_PRIVATE_KEY)
                throw new Exception("PKCS#11 URI does not specify private key");

            // Load and initialize PKCS#11 library specified by URI
            CKR rv = CKR.CKR_OK;

            using (Pkcs11 pkcs11 = new Pkcs11(pkcs11Uri.ModulePath, true))
            {
                rv = pkcs11.C_Initialize(Settings.InitArgs40);
                if ((rv != CKR.CKR_OK) && (rv != CKR.CKR_CRYPTOKI_ALREADY_INITIALIZED))
                    Assert.Fail(rv.ToString());

                //  Obtain a list of all slots with tokens that match URI
                uint[] slots = null;
                
                rv = Pkcs11UriUtils.GetMatchingSlotList(pkcs11Uri, pkcs11, true, out slots);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                if ((slots == null) || (slots.Length == 0))
                    throw new Exception("None of the slots matches PKCS#11 URI");

                // Open read only session with first token that matches URI
                uint session = CK.CK_INVALID_HANDLE;

                rv = pkcs11.C_OpenSession(slots[0], (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 with PIN acquired from URI
                byte[] pinValue = ConvertUtils.Utf8StringToBytes(pkcs11Uri.PinValue);

                rv = pkcs11.C_Login(session, CKU.CKU_USER, pinValue, Convert.ToUInt32(pinValue.Length));
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                // Get list of object attributes for the private key specified by URI
                CK_ATTRIBUTE[] attributes = null;

                Pkcs11UriUtils.GetObjectAttributes(pkcs11Uri, out attributes);

                // Find private key specified by URI
                uint foundObjectCount = 0;
                uint[] foundObjectIds = new uint[] { CK.CK_INVALID_HANDLE };

                rv = pkcs11.C_FindObjectsInit(session, attributes, Convert.ToUInt32(attributes.Length));
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                rv = pkcs11.C_FindObjects(session, foundObjectIds, Convert.ToUInt32(foundObjectIds.Length), ref foundObjectCount);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                rv = pkcs11.C_FindObjectsFinal(session);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                if ((foundObjectCount == 0) || (foundObjectIds[0] == CK.CK_INVALID_HANDLE))
                    throw new Exception("None of the private keys match PKCS#11 URI");

                // Create signature with the private key specified by URI
                CK_MECHANISM mechanism = CkmUtils.CreateMechanism(CKM.CKM_SHA1_RSA_PKCS);

                rv = pkcs11.C_SignInit(session, ref mechanism, foundObjectIds[0]);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                uint signatureLen = 0;

                rv = pkcs11.C_Sign(session, data, Convert.ToUInt32(data.Length), null, ref signatureLen);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                Assert.IsTrue(signatureLen > 0);

                byte[] signature = new byte[signatureLen];

                rv = pkcs11.C_Sign(session, data, Convert.ToUInt32(data.Length), signature, ref signatureLen);
                if (rv != CKR.CKR_OK)
                    Assert.Fail(rv.ToString());

                if (signature.Length != signatureLen)
                    Array.Resize(ref signature, Convert.ToInt32(signatureLen));

                // Release PKCS#11 resources
                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());

                return signature;
            }
        }