/// <summary>
/// 对7位数的普通通信进行加密；
/// </summary>
/// <param name="whoDate">接收方还是发送方的数据</param>
/// <param name="code">暗号</param>
/// <param name="fileLabel">文件标签</param>
/// <returns>加密完成的数据</returns>
internal static byte[] FileSevenEncryption(byte whoDate, byte code, int fileLabel)
{
byte[] haveDate = new byte[7];
haveDate[0] = CipherCode._fileCode;
haveDate[1] = whoDate;
haveDate[2] = code;
ByteToDate.IntToByte(fileLabel, 3, haveDate);
return(haveDate);
}
/// <summary>
/// 对TCP发送进行粘包加密
/// </summary>
/// <param name="sendDate">要加密的数据</param>
/// <returns>加密之后的数据为：粘包代码4byte+数据包长度4byte</returns>
/// <remarks>把数据包处理为：粘包代码4byte+数据包长度4byte</remarks>
internal static void EncryptionPackage(ref byte[] sendDate)
{
//把数据包处理为：粘包代码4byte+数据包长度4byte
byte[] dateAll = new byte[sendDate.Length + 8];
ByteToDate.IntToByte(CipherCode._stickPackageCode, 0, dateAll);
ByteToDate.IntToByte(sendDate.Length, 4, dateAll);
sendDate.CopyTo(dateAll, 8);
sendDate = dateAll;
}
/// <summary>
/// 用于接收方；对续传时回复长度的数据进行加密
/// </summary>
/// <param name="code">是同意时还是发起方</param>
/// <param name="fileState">FileState</param>
/// <returns>加密之后的数据</returns>
internal static byte[] ReceiveContingueEncryption(byte code, FileState fileState)
{
byte[] haveDate = new byte[15];
haveDate[0] = CipherCode._fileCode;
haveDate[1] = CipherCode._receiveUser;
haveDate[2] = code;
ByteToDate.IntToByte(fileState.FileLabel, 3, haveDate);
ByteToDate.IntToByte(fileState.FileOkLenth, 7, haveDate);
return(haveDate);
}
/// <summary>
/// 发送方对一个文件包头进行加密得到一个byte[]
/// </summary>
/// <param name="fileSend"></param>
/// <returns></returns>
internal static byte[] FileHeadEncryption(FileState fileSend)
{
string fileName = CommonMethod.StringRight(fileSend.FileName, "\\");
byte[] fileNameByte = Encoding.UTF8.GetBytes(fileName);
byte[] haveDate = new byte[15 + fileNameByte.Length];
haveDate[0] = CipherCode._fileCode;
haveDate[1] = CipherCode._sendUser;
haveDate[2] = CipherCode._fileHeadCode;
ByteToDate.IntToByte(fileSend.FileLabel, 3, haveDate);
ByteToDate.IntToByte(fileSend.FileLenth, 7, haveDate);
fileNameByte.CopyTo(haveDate, 15);
return(haveDate);
}
/// <summary>
/// 返回分包数据11位的数据包包头（暗号类型1+暗号1+原暗号+数据标签+长度）
/// </summary>
/// <param name="date">数据</param>
/// <param name="textCode">原暗号，什么文件</param>
/// <param name="state">StateBase</param>
/// <returns>加密之后的包头</returns>
internal static byte[] SendHeadEncryption(byte[] date, byte textCode, TransmitData state)
{
state.SendFile = new TransmitFile(date);
state.SendFile.FileLabel = RandomPublic.RandomNumber(14562);
byte[] headDate = new byte[11];
//写入暗号
headDate[0] = CipherCode._bigDateCode;
headDate[1] = CipherCode._fileHeadCode;
headDate[2] = textCode;
//写入数据标签
ByteToDate.IntToByte(state.SendFile.FileLabel, 3, headDate);
//写入数据长度
ByteToDate.IntToByte(date.Length, 7, headDate);
return(headDate);
}
/// <summary>
/// 文件解密
/// </summary>
/// <param name="date">数据</param>
/// <param name="state">StateBase</param>
/// <returns>StateCode</returns>
internal static DataModel FileDecrypt(byte[] date, TransmitData state)
{
DataModel stateCode = null;
if (date.Length < 6)
{
return(stateCode);
}
byte headDate = date[1];
if (headDate == CipherCode._fileAgreeReceive)
{//对方同意接收文件;我应该怎么处理
int FileLabel = ByteToDate.ByteToInt(2, date);
if (state.SendFile != null && state.SendFile.FileLabel == FileLabel)
{
byte[] SendSubjectDate = FileGetSendDate(state);
if (SendSubjectDate == null)
{
stateCode = new DataModel(CipherCode._dateSuccess);
}
else
{
stateCode = new DataModel(SendSubjectDate);//直接发送
}
}
}
else if (headDate == CipherCode._dateSuccess)
{//对方已经接收到数据
int FileLabel = ByteToDate.ByteToInt(2, date);
if (state.SendFile != null && state.SendFile.FileLabel == FileLabel)
{
byte[] SendSubjectDate = FileGetSendDate(state);
if (SendSubjectDate == null)
{
stateCode = new DataModel(CipherCode._dateSuccess);
}
else
{
stateCode = new DataModel(SendSubjectDate);//直接发送
}
}
}
//上面是发送方接收要做的;下面是接收方发送要做的事情
else if (headDate == CipherCode._fileHeadCode)
{ //收到的是文件包头部分
byte whatCode = date[2]; //原暗号
int fileLabel = ByteToDate.ByteToInt(3, date); //数据标签
int fileLenth = ByteToDate.ByteToInt(7, date); //长度
state.ReceiveFile = new TransmitFile(whatCode, fileLabel, fileLenth);
byte[] dateAll = new byte[6];
dateAll[0] = CipherCode._bigDateCode;
dateAll[1] = CipherCode._fileAgreeReceive;
ByteToDate.IntToByte(fileLabel, 2, dateAll);
stateCode = new DataModel(dateAll);
}
else if (headDate == CipherCode._fileSubjectCode)
{//收到的是文件主体部分
int SendDateLabel = 0;
byte[] dateAll = ByteToDate.OffsetDecrypt(date, out SendDateLabel, 2);
byte[] ReplyDate = ByteToDate.CombinationTwo(CipherCode._bigDateCode, CipherCode._dateSuccess, state.ReceiveFile.FileLabel);
if (state.ReceiveFile.FileDateAll == null)
{
state.ReceiveFile.FileDateAll = dateAll;//是第一次接收到主体数据
stateCode = new DataModel(ReplyDate);
}
else
{
byte[] FileDateAll = new byte[state.ReceiveFile.FileDateAll.Length + dateAll.Length];
state.ReceiveFile.FileDateAll.CopyTo(FileDateAll, 0);
dateAll.CopyTo(FileDateAll, state.ReceiveFile.FileDateAll.Length);
state.ReceiveFile.FileDateAll = FileDateAll;
if (FileDateAll.Length == state.ReceiveFile.FileLenth)
{
if (state.ReceiveFile.FileClassification == CipherCode._textCode)
{
string str = Encoding.UTF8.GetString(FileDateAll);
stateCode = new DataModel(CipherCode._textCode, str, ReplyDate);
}
else
{
stateCode = new DataModel(CipherCode._photographCode, FileDateAll, ReplyDate);
}
state.ReceiveFile = null;//文件接收完成；释放接收器
}
else
{
stateCode = new DataModel(ReplyDate);
}
}
}
return(stateCode);
}
