[小技巧]一款KeygenMe的分析与注册机的编写

 1 //计算字符串哈希值
 2 DWORD C__02_注册机Dlg::CalcHash_str(PBYTE name, DWORD len)
 3 {
 4     DWORD ret = 0;
 5     int temp_len = len;        //长度参数
 6     DWORD dwTemp = 0;
 7     do
 8     {
 9         *(PBYTE)&dwTemp = (BYTE)*name;                
10         dwTemp = (DWORD)(ret * 72 - dwTemp - 111);
11         ret = dwTemp ^ 0xBACAF;
12         ++name;
13         --temp_len;
14     } while (temp_len);
15 
16     return ret;
17 }
18 
19 //计算两个整形的哈希值
20 DWORD C__02_注册机Dlg::CalcHash_dword(DWORD a1, DWORD a2)
21 {
22     return (a2 ^ a1 ^ 0xFFAC) + (a2 ^ 0x553) - 1 + (a2 ^ 0x553) + a1;
23 }
24 
25 //把哈希值转为字符串
26 bool C__02_注册机Dlg::toAnsi(char* Buffer, DWORD hash)
27 {
28     Buffer += 7;
29     for (int i = 0; i < 8; i++)
30     {
31         DWORD a = hash % 0x10 + 0x30;
32         if (a >= 0x3A)
33         {
34             a += 7;
35         }
36         *Buffer = a;
37         Buffer--;
38         hash /= 0x10;
39     }
40     return true;
41 }
42 
43 //填充格式化序列号
44 void C__02_注册机Dlg::FillSer(char* buff)
45 {
46     *(buff + 4) = 0x2D;
47     *(buff + 4 + 10) = 0x2D;
48     *(buff) = 0x4B;
49     *(buff + 1) = 0x4F;
50     *(buff + 2) = 0x53;
51 }
52 
53 
54 //按钮事件
55 void C__02_注册机Dlg::OnBnClickedButton1()
56 {
57     CString str;
58     m_Edit_Name.GetWindowTextW(str);        //获取用户输入name
59     if (str.IsEmpty())
60     {
61         AfxMessageBox(L"请输入name!");
62         return;
63     }
64     if (str.GetLength() <=3 || str.GetLength() > 19)
65     {
66         AfxMessageBox(L"name长度不合法.(合法长度>3 && <=19)");
67         return;
68     }
69     
70     char szName[MAX_PATH] = { 0 };
71     WideCharToMultiByte(CP_ACP, 0, str.GetBuffer(), str.GetLength(), szName, MAX_PATH, 0, 0);    //宽字符转换多字节
72 
73     DWORD haxi_Name = CalcHash_str((PBYTE)szName, strlen(szName));
74 
75     DWORD pcbBuffer = MAX_PATH;
76     char szUserName[MAX_PATH] = { 0 };
77     GetUserNameA(szUserName, &pcbBuffer);            //获取系统用户名
78 
79     DWORD haxi_UserName = CalcHash_str((PBYTE)szUserName, strlen(szName));
80     DWORD haxi_Double = CalcHash_dword(haxi_Name, haxi_UserName);
81 
82     char szBuf[25] = { 0 };
83     toAnsi(&szBuf[0], haxi_UserName);
84     toAnsi(&szBuf[8], haxi_Double);
85     toAnsi(&szBuf[16], haxi_Name);                  //哈希值转换字符串
86     FillSer(szBuf);                                  //格式化填充序列号
87 
88     str = szBuf;
89     m_Edit_Serial.SetWindowTextW(str);             //计算完毕
90 }