/* ==================================================================== Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. ==================================================================== */ using System; using System.Collections.Generic; using System.Text; using System.IO; using System.Security; using System.Security.Cryptography; using HH.WMS.Utils.NPOI.POIFS.FileSystem; using HH.WMS.Utils.NPOI.Util; namespace HH.WMS.Utils.NPOI.POIFS.Crypt { public class EcmaDecryptor : Decryptor { private EncryptionInfo info; private byte[] passwordHash; public EcmaDecryptor(EncryptionInfo info) { this.info = info; } private byte[] GenerateKey(int block) { try { HashAlgorithm sha1 = HashAlgorithm.Create("SHA1"); //sha1.update(passwordHash); byte[] blockValue = new byte[4]; LittleEndian.PutInt(blockValue, block); byte[] temp = new byte[blockValue.Length + passwordHash.Length]; Array.Copy(passwordHash, temp, passwordHash.Length); Array.Copy(blockValue, 0, temp, passwordHash.Length, blockValue.Length); byte[] finalHash = sha1.ComputeHash(temp); //sha1.digest(blockValue); int reqiredKeyLength = (info.Header.KeySize) / 8; byte[] buff = new byte[64]; for (int i = 0; i < buff.Length; i++) buff[i] = (byte)0x36; for (int i = 0; i < finalHash.Length; i++) buff[i] = (byte)(buff[i] ^ finalHash[i]); //sha1.Clear(); byte[] x1 = sha1.ComputeHash(buff); for (int i = 0; i < buff.Length; i++) buff[i] = (byte)0x5c; for (int i = 0; i < finalHash.Length; i++) buff[i] = (byte)(buff[i] ^ finalHash[i]); //sha1.Clear(); byte[] x2 = sha1.ComputeHash(buff); byte[] x3 = new byte[x1.Length + x2.Length]; System.Array.Copy(x1, 0, x3, 0, x1.Length); System.Array.Copy(x2, 0, x3, x1.Length, x2.Length); return TruncateOrPad(x3, reqiredKeyLength); } catch (System.Security.Cryptography.CryptographicException ex) { throw ex; } } public override bool VerifyPassword(string password) { passwordHash = HashPassword(info, password); SymmetricAlgorithm cipher = GetCipher(); byte[] verifier; // byte[] verifier = cipher.doFinal(info.getVerifier().getVerifier()); //using (MemoryStream fStream = new MemoryStream(info.Verifier.Verifier)) //{ // using (CryptoStream cStream = new CryptoStream(fStream, cipher.CreateDecryptor(cipher.Key, cipher.IV), // CryptoStreamMode.Read)) // { // verifier = new byte[cStream.Length];//?? // cStream.Read(verifier, 0, verifier.Length); // } //} verifier = Decrypt(cipher, info.Verifier.Verifier); HashAlgorithm sha1 = HashAlgorithm.Create("SHA1"); byte[] calcVerifierHash = sha1.ComputeHash(verifier); byte[] temp; //using (MemoryStream fStream = new MemoryStream(info.Verifier.VerifierHash)) //{ // using (CryptoStream cStream = new CryptoStream(fStream, cipher.CreateDecryptor(cipher.Key, cipher.IV), // CryptoStreamMode.Read)) // { // temp = new byte[cStream.Length]; // cStream.Read(temp, 0, verifier.Length); // } //} temp = Decrypt(cipher, info.Verifier.VerifierHash); byte[] verifierHash = TruncateOrPad(calcVerifierHash, calcVerifierHash.Length); return Arrays.Equals(calcVerifierHash, verifierHash); } private byte[] TruncateOrPad(byte[] source, int length) { byte[] result = new byte[length]; System.Array.Copy(source, 0, result, 0, Math.Min(length, source.Length)); if (length > source.Length) { for (int i = source.Length; i < length; i++) result[i] = 0; } return result; } private SymmetricAlgorithm GetCipher() { byte[] key = GenerateKey(0); //System.Security.Cryptography SymmetricAlgorithm cipher = SymmetricAlgorithm.Create(); // AES/ECB/NoPadding cipher.Mode = CipherMode.ECB; cipher.Padding = PaddingMode.None; cipher.Key = key; //cipher.init(Cipher.DECRYPT_MODE, skey); Leon return cipher; } public override Stream GetDataStream(DirectoryNode dir) { DocumentInputStream dr = dir.CreateDocumentInputStream("EncryptedPackage"); long size = dr.ReadLong(); SymmetricAlgorithm cipher=GetCipher(); return new CryptoStream(dr, cipher.CreateDecryptor(cipher.Key, cipher.IV), CryptoStreamMode.Read); } } }