/// <summary>
/// 加密文件
/// </summary>
/// <param name="srcFile">源绝对路径</param>
/// <param name="destFile">目的绝对路径</param>
public void encryptFile(string srcFile, string destFile, string password)
{
using (FileStream fsrc = File.OpenRead(srcFile),
fdest = File.OpenWrite(destFile))
{
long lSize = fsrc.Length;
byte[] buffer = new byte[BUFSIZE];
int tmpRead = -1;
int totalRead = 0;
byte[] IV = SMFCBC.GenerateRandomBytes(16);
byte[] SALT = SMFCBC.GenerateRandomBytes(16);
PasswordDeriveBytes pdb = new PasswordDeriveBytes(password, SALT, "SHA256", 100);
byte[] KEY = pdb.GetBytes(16);
//往文件头添加IV和SALT值
fdest.Write(IV, 0, IV.Length);
fdest.Write(SALT, 0, SALT.Length);
//创建SM4加密器和SHA256散列器
SMFCBC smfencryptor = new SMFCBC();
HashAlgorithm hasher = SHA256.Create();
using (CryptoStream cdest = new CryptoStream(fdest,
smfencryptor.CreateEncryptor(KEY, IV),
CryptoStreamMode.Write),
chash = new CryptoStream(Stream.Null, hasher, CryptoStreamMode.Write))
{
//包装加密流
BinaryWriter bw_dest = new BinaryWriter(cdest);
//加密开头为长度和文件标识
bw_dest.Write(lSize);
bw_dest.Write(SM4_TAG);
while ((tmpRead = fsrc.Read(buffer, 0, buffer.Length)) != 0)
{
bw_dest.Write(buffer, 0, tmpRead);
chash.Write(buffer, 0, tmpRead);
totalRead += tmpRead;
}
//关闭SHA256散列器
chash.Flush();
chash.Close();
byte[] HASH = hasher.Hash;
bw_dest.Write(HASH, 0, HASH.Length);
//关闭二进制包装类
bw_dest.Flush();
bw_dest.Close();
}
}
}
/// <summary>
/// 可取消文件加密
/// </summary>
/// <param name="srcFile"></param>
/// <param name="destFile"></param>
/// <param name="password"></param>
/// <param name="asyOp"></param>
private void encryptFileAsync(string srcFile, string destFile, string password, AsyncOperation asyOp)
{
FileStream fsrc = null, fdest = null;
CryptoStream cdest = null, chash = null;
BinaryWriter bwdest = null;
try
{
fsrc = File.OpenRead(srcFile);
fdest = File.OpenWrite(destFile);
long lSize = fsrc.Length;
byte[] buffer = new byte[BUFSIZE];
int tmpRead = -1;
int totalRead = 0;
byte[] IV = SMFCBC.GenerateRandomBytes(16);
byte[] SALT = SMFCBC.GenerateRandomBytes(16);
PasswordDeriveBytes pdb = new PasswordDeriveBytes(password, SALT, "SHA256", 100);
byte[] KEY = pdb.GetBytes(16);
//往文件头添加IV和SALT值
fdest.Write(IV, 0, IV.Length);
fdest.Write(SALT, 0, SALT.Length);
//创建SM4加密器和SHA256散列器
SMFCBC smfencryptor = new SMFCBC();
HashAlgorithm hasher = SHA256.Create();
cdest = new CryptoStream(fdest, smfencryptor.CreateEncryptor(KEY, IV), CryptoStreamMode.Write);
chash = new CryptoStream(Stream.Null, hasher, CryptoStreamMode.Write);
//包装加密流
bwdest = new BinaryWriter(cdest);
//加密开头为长度和文件标识
bwdest.Write(lSize);
bwdest.Write(SM4_TAG);
//增加报告进度
int totalNumber = (int)(lSize / BUFSIZE);
while ((tmpRead = fsrc.Read(buffer, 0, buffer.Length)) != 0)
{
bwdest.Write(buffer, 0, tmpRead);
chash.Write(buffer, 0, tmpRead);
totalRead += tmpRead;
//报告进度
asyOp.Post(onTaskStateChangedReportDelgate, new TaskStateChangedEventArgs()
{
CryptState = CryptState.Encrypt,
Description = "加密中",
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);
}
}
//关闭SHA256散列器
chash.Flush();
chash.Close();
byte[] HASH = hasher.Hash;
bwdest.Write(HASH, 0, HASH.Length);
//关闭二进制包装类
bwdest.Flush();
bwdest.Close();
}
catch (Exception e)
{
throw e;
}
finally
{
//顺序不可颠倒
if (bwdest != null)
{
bwdest.Close();
}
if (chash != null)
{
chash.Close();
}
if (cdest != null)
{
cdest.Close();
}
if (fdest != null)
{
fdest.Close();
}
if (fsrc != null)
{
fsrc.Close();
}
}
return;
}