/// <summary>
/// 可取消文件解密
/// </summary>
/// <param name="srcFile"></param>
/// <param name="destFile"></param>
/// <param name="password"></param>
/// <param name="asyOp"></param>
private void decryptFileAsync(string srcFile, string destFile, string password, AsyncOperation asyOp)
{
FileStream fsrc = null, fdest = null;
CryptoStream cdest = null, chash = null;
BinaryReader brdest = null;
try {
fsrc = File.OpenRead(srcFile);
fdest = File.OpenWrite(destFile);
long lSize = (int)srcFile.Length;
byte[] buffer = new byte[BUFSIZE];
int hasRead = -1;
int totalRead = 0;
byte[] IV = new byte[16];
byte[] SALT = new byte[16];
fsrc.Read(IV, 0, 16);
fsrc.Read(SALT, 0, 16);
PasswordDeriveBytes pdb = new PasswordDeriveBytes(password, SALT, "SHA256", 100);
byte[] KEY = pdb.GetBytes(16);
//创建SM4解密器和SHA256散列器
SMFCBC smfdecryptor = new SMFCBC();
HashAlgorithm hasher = SHA256.Create();
cdest = new CryptoStream(fsrc, smfdecryptor.CreateDecryptor(KEY, IV), CryptoStreamMode.Read);
chash = new CryptoStream(Stream.Null, hasher, CryptoStreamMode.Write);
BinaryReader brDest = new BinaryReader(cdest);
lSize = brDest.ReadInt64();
ulong tag = brDest.ReadUInt64();
if (tag != SM4_TAG)
{
throw new Exception("文件解密出错(口令不对，或者不是加密文件)");
}
long numReads = lSize / BUFSIZE;
long numRest = (long)lSize % BUFSIZE;
//增加报告
int totalNumber = (int)(lSize / BUFSIZE);
for (int i = 0; i < numReads; i++)
{
hasRead = brDest.Read(buffer, 0, buffer.Length);
fdest.Write(buffer, 0, hasRead);
chash.Write(buffer, 0, hasRead);
totalRead += hasRead;
//报告进度
asyOp.Post(onTaskStateChangedReportDelgate, new TaskStateChangedEventArgs()
{
CryptState = CryptState.Decrypt,
Description = "解密中",
TaskID = 0,
CurrentNumber = totalRead / BUFSIZE,
TotalNumber = totalNumber
});
//如果取消，则抛出取消异常
if (token.IsCancellationRequested)
{
throw new OperationCanceledException(token);
}
}
if (numRest > 0)
{
hasRead = brDest.Read(buffer, 0, (int)numRest);
fdest.Write(buffer, 0, hasRead);
chash.Write(buffer, 0, hasRead);
totalRead += hasRead;
}
//关闭散列器
chash.Flush();
chash.Close();
fdest.Flush();
fdest.Close();
byte[] curHash = hasher.Hash;
//和文件中的散列值比较
byte[] oldHash = new byte[hasher.HashSize / 8];
hasRead = brDest.Read(oldHash, 0, oldHash.Length);
if ((oldHash.Length != hasRead) || (!CheckByteArrays(oldHash, curHash)))
{
throw new Exception("文件经过修改");
}
brDest.Close();
if (totalRead != lSize)
{
throw new Exception("文件长度不对");
}
}
catch (Exception e)
{
throw e;
}
finally
{
//顺序不可颠倒
if (brdest != null)
{
brdest.Close();
}
if (chash != null)
{
chash.Close();
}
if (cdest != null)
{
cdest.Close();
}
if (fdest != null)
{
fdest.Close();
}
if (fsrc != null)
{
fsrc.Close();
}
}
return;
}
/// <summary>
/// 解密文件
/// </summary>
/// <param name="srcFile"></param>
/// <param name="destFile"></param>
/// <param name="password"></param>
public void decryptFile(string srcFile, string destFile, string password)
{
using (FileStream fsrc = File.OpenRead(srcFile),
fdest = File.OpenWrite(destFile))
{
long lSize = (int)srcFile.Length;
byte[] buffer = new byte[BUFSIZE];
int hasRead = -1;
int totalRead = 0;
byte[] IV = new byte[16];
byte[] SALT = new byte[16];
fsrc.Read(IV, 0, 16);
fsrc.Read(SALT, 0, 16);
PasswordDeriveBytes pdb = new PasswordDeriveBytes(password, SALT, "SHA256", 100);
byte[] KEY = pdb.GetBytes(16);
//创建SM4解密器和SHA256散列器
SMFCBC smfdecryptor = new SMFCBC();
HashAlgorithm hasher = SHA256.Create();
using (CryptoStream cdest = new CryptoStream(fsrc, smfdecryptor.CreateDecryptor(KEY, IV), CryptoStreamMode.Read),
chash = new CryptoStream(Stream.Null, hasher, CryptoStreamMode.Write))
{
BinaryReader brDest = new BinaryReader(cdest);
lSize = brDest.ReadInt64();
ulong tag = brDest.ReadUInt64();
if (tag != SM4_TAG)
{
throw new Exception("文件非加密文件");
}
long numReads = lSize / BUFSIZE;
long numRest = (long)lSize % BUFSIZE;
for (int i = 0; i < numReads; i++)
{
hasRead = brDest.Read(buffer, 0, buffer.Length);
fdest.Write(buffer, 0, hasRead);
chash.Write(buffer, 0, hasRead);
totalRead += hasRead;
}
if (numRest > 0)
{
hasRead = brDest.Read(buffer, 0, (int)numRest);
fdest.Write(buffer, 0, hasRead);
chash.Write(buffer, 0, hasRead);
totalRead += hasRead;
}
//关闭散列器
chash.Flush();
chash.Close();
fdest.Flush();
fdest.Close();
byte[] curHash = hasher.Hash;
//和文件中的散列值比较
byte[] oldHash = new byte[hasher.HashSize / 8];
hasRead = brDest.Read(oldHash, 0, oldHash.Length);
if ((oldHash.Length != hasRead) || (!CheckByteArrays(oldHash, curHash)))
{
throw new Exception("文件经过修改");
}
brDest.Close();
if (totalRead != lSize)
{
throw new Exception("文件长度不对");
}
}
}
}
public void SMFCBCTest()
{
SMFCBC smfcbcAlg = SMFCBC.Create();
int total = 0;
byte[] data = new byte[256];
for (int i = 0; i < 256; i++)
{
data[i] = (byte)i;
}
string FileName = "D:\\github\\SMFTool\\SMFcrypto\\CryptoTool\\CryptoToolTests\\bin\\Debug\\output.txt";
try
{
FileStream fStream = File.Open(FileName, FileMode.Create);
SMFCBC smfcrypto = new SMFCBC();
CryptoStream cStream = new CryptoStream(fStream,
smfcrypto.CreateEncryptor(smfcbcAlg.Key, smfcbcAlg.IV),
CryptoStreamMode.Write);
BinaryWriter sWriter = new BinaryWriter(cStream);
try
{
sWriter.Write(data);
sWriter.Write(data);
total += data.Length;
total += data.Length;
}
catch (Exception e)
{
Console.WriteLine("An error occurred: {0}", e.Message);
}
finally
{
sWriter.Close();
cStream.Close();
fStream.Close();
smfcrypto.Clear();
}
}
catch (CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
}
catch (UnauthorizedAccessException e)
{
Console.WriteLine("A file error occurred: {0}", e.Message);
}
byte[] res;
try
{
FileStream fStream = File.Open(FileName, FileMode.OpenOrCreate);
SMFCBC smfcrypto = new SMFCBC();
CryptoStream cStream = new CryptoStream(fStream,
smfcrypto.CreateDecryptor(smfcbcAlg.Key, smfcbcAlg.IV),
CryptoStreamMode.Read);
BinaryReader sReader = new BinaryReader(cStream);
byte[] resc = new byte[256];
try
{
for (int i = 0; i < 4; i++)
{
res = sReader.ReadBytes(256);
Array.Copy(res, 0, resc, 0, res.Length);
}
}
catch (Exception e)
{
Console.WriteLine("An error occurred: {0}", e.Message);
}
finally
{
sReader.Close();
cStream.Close();
fStream.Close();
smfcrypto.Clear();
}
}
catch (CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
}
catch (UnauthorizedAccessException e)
{
Console.WriteLine("A file error occurred: {0}", e.Message);
}
smfcbcAlg.Clear();
return;
}