/// <summary> /// 加密文件 /// </summary> /// <param name="inFile">待加密文件</param> /// <param name="outFile">加密后输入文件</param> /// <param name="password">加密密码</param> public static void EncryptFile(string inFile, string outFile, string password) { using (FileStream fin = File.OpenRead(inFile), fout = File.OpenWrite(outFile)) { byte [] bfilename = Encoding.Default.GetBytes(Path.GetFileName(inFile) + "\n"); fout.Write(bfilename, 0, bfilename.Length); long lSize = fin.Length; // 输入文件长度 int size = (int)lSize; byte[] bytes = new byte[BUFFER_SIZE]; // 缓存 int read = -1; // 输入文件读取数量 int value = 0; // 获取IV和salt byte[] IV = GenerateRandomBytes(16); byte[] salt = GenerateRandomBytes(16); // 创建加密对象 SymmetricAlgorithm sma = CryptoHelp.CreateRijndael(password, salt); sma.IV = IV; // 在输出文件开始部分写入IV和salt fout.Write(IV, 0, IV.Length); fout.Write(salt, 0, salt.Length); // 创建散列加密 HashAlgorithm hasher = SHA256.Create(); using (CryptoStream cout = new CryptoStream(fout, sma.CreateEncryptor(), CryptoStreamMode.Write), chash = new CryptoStream(Stream.Null, hasher, CryptoStreamMode.Write)) { BinaryWriter bw = new BinaryWriter(cout); bw.Write(lSize); bw.Write(FC_TAG); // 读写字节块到加密流缓冲区 while ((read = fin.Read(bytes, 0, bytes.Length)) != 0) { cout.Write(bytes, 0, read); chash.Write(bytes, 0, read); value += read; } // 关闭加密流 chash.Flush(); chash.Close(); // 读取散列 byte[] hash = hasher.Hash; // 输入文件写入散列 cout.Write(hash, 0, hash.Length); // 关闭文件流 cout.Flush(); cout.Close(); } } }
private void btnStart_Click(object sender, EventArgs e) { if (this.txtFile.Text.Equals("")) { if (this.rbtnDecrypt.Checked) { this.statusLblContext.Text = "请选择要解密的文件"; } else { this.statusLblContext.Text = "请选择要加密的文件"; } return; } if (!(System.IO.File.Exists(this.txtFile.Text.Trim()) || System.IO.Directory.Exists(this.txtFile.Text.Trim()))) { this.statusLblContext.Text = "你选择的文件或者目录不存在"; return; } if (this.txtPwd.Text.Equals("")) { if (this.rbtnDecrypt.Checked) { this.statusLblContext.Text = "请输入要解密的密码"; } else { this.statusLblContext.Text = "请输入要加密的密码"; } return; } SaveFileDialog savefile = new SaveFileDialog(); if (this.rbtnDecrypt.Checked) { string file = CryptoHelp.DecryptFileName(this.txtFile.Text.Trim()); if ("" == file) { file = "*"; } savefile.Filter = string.Format("所有文件(*.{0})|*.{0}", System.IO.Path.GetExtension(file)); } else { savefile.Filter = "密码文件(*.rg)|*.rg"; } string path = ""; if (savefile.ShowDialog() == DialogResult.OK) { path = savefile.FileName; Thread th = new Thread(new ThreadStart(Wait)); th.Start(); try { if (this.rbtnDecrypt.Checked) { hotManager.CryptoHelp.DecryptFile(this.txtFile.Text, path, this.txtPwd.Text); } else { hotManager.CryptoHelp.EncryptFile(this.txtFile.Text, path, this.txtPwd.Text); } this.statusLblContext.Text = "操作完成"; } catch { this.statusLblContext.Text = "操作失败"; } th.Abort(); } }
/// <summary> /// 解密文件 /// </summary> /// <param name="inFile">待解密文件</param> /// <param name="outFile">解密后输出文件</param> /// <param name="password">解密密码</param> public static void DecryptFile(string inFile, string outFile, string password) { // 创建打开文件流 using (FileStream fin = File.OpenRead(inFile), fout = File.OpenWrite(outFile)) { int size = (int)fin.Length; byte[] bytes = new byte[BUFFER_SIZE]; int read = -1; int value = 0; int outValue = 0; fin.Read(bytes, 0, 1024); string file = Encoding.Default.GetString(bytes); file = file.Remove(file.IndexOf("\n")); byte [] bytef = Encoding.Default.GetBytes(file + "\n"); fin.Seek(bytef.Length, SeekOrigin.Begin); byte[] IV = new byte[16]; fin.Read(IV, 0, 16); byte[] salt = new byte[16]; fin.Read(salt, 0, 16); SymmetricAlgorithm sma = CryptoHelp.CreateRijndael(password, salt); sma.IV = IV; value = 32; long lSize = -1; // 创建散列对象, 校验文件 HashAlgorithm hasher = SHA256.Create(); using (CryptoStream cin = new CryptoStream(fin, sma.CreateDecryptor(), CryptoStreamMode.Read), chash = new CryptoStream(Stream.Null, hasher, CryptoStreamMode.Write)) { // 读取文件长度 BinaryReader br = new BinaryReader(cin); lSize = br.ReadInt64(); ulong tag = br.ReadUInt64(); if (FC_TAG != tag) { throw new CryptoHelpException("文件被破坏"); } long numReads = lSize / BUFFER_SIZE; long slack = (long)lSize % BUFFER_SIZE; for (int i = 0; i < numReads; ++i) { read = cin.Read(bytes, 0, bytes.Length); fout.Write(bytes, 0, read); chash.Write(bytes, 0, read); value += read; outValue += read; } if (slack > 0) { read = cin.Read(bytes, 0, (int)slack); fout.Write(bytes, 0, read); chash.Write(bytes, 0, read); value += read; outValue += read; } chash.Flush(); chash.Close(); fout.Flush(); fout.Close(); byte[] curHash = hasher.Hash; // 获取比较和旧的散列对象 byte[] oldHash = new byte[hasher.HashSize / 8]; read = cin.Read(oldHash, 0, oldHash.Length); if ((oldHash.Length != read) || (!CheckByteArrays(oldHash, curHash))) { throw new CryptoHelpException("文件被破坏"); } } if (outValue != lSize) { throw new CryptoHelpException("文件大小不匹配"); } } }