Research and crack of licensing and authorization

A very nice interface control for office 07. Can browse under:

http://www.divelements.com/net/

The non-registered version has a 30-day usage limit. With. NET reflector, you can see the key places:

Namespace Divelements.Util.Registration

{

。。。

Codeprivate bool xa1d7cab22b1cb36a ()
{
String str2;
AssemblyName name = Assembly.getexecutingassembly (). GetName ();
String assemblyproductname = x294bd621a33dc533. Getassemblyproductname (assembly.getexecutingassembly ());
using (SHA1 sha = SHA1. Create ())
{
string s = String. Concat (new object[] {assemblyproductname, name. Version.major, ".", name. Version.minor, ".", name. Version.build});
str2 = convert.tobase64string (Sha.computehash (Encoding.Default.GetBytes (s));
}
RegistryKey key = Registry.CurrentUser.OpenSubKey (@ "software\microsoft\. NETFramework ", true);
if (key = = null)
{
Try
{
Key = Registry.CurrentUser.CreateSubKey (@ "software\microsoft\. NETFramework ");
}
Catch
{
return true;
}
}
DateTime minValue = Datetime.minvalue;
Try
{
String STR4 = (string) key. GetValue (STR2);
if (STR4 = = null)
{
Key. SetValue (STR2, DateTime.Now.ToFileTime (). ToString ());
return false;
}
MinValue = Datetime.fromfiletime (long. Parse (STR4));
}
Finally
{
Key. Close ();
}
Return (DateTime.Now > (minValue + new TimeSpan (30, 0, 0, 0));
}

The company uses the. NET-brought copyright control mechanism, so it's cumbersome and easy to get together.

Originally thought to be through the network to verify whether the expiration, it seems that the original use of. NET operation of the registry.

Anyway, as long as the above method returns false, it can be bypassed. Returns true if it expires.

The method of cracking is to modify IL directly. If you decompile, an error occurs. After all, Xenocode was used.

1. First use Ildasm.exe to extract the DLL as IL. The command is:

ILDASM divelements.sandribbon.dll/out=divelements.sandribbon.il

2. Then look for the class: xa1d7cab22b1cb36a. Just a search. To find the method inside: There is a TimeSpan setting:

LDC.I4.S 30

Revision changed to

Ldc.i4 3650

3. Re-pack:

C:\windows\microsoft.net\framework\v2.0.50727\ilasm/res:divelements. Sandribbon.res/resource=divelements.sandribbon.clientpanel.png/resource= Divelements.SandRibbon.ContextPopup.png divelements.sandribbon.il/resource= Divelements.sandribbon.resources.check.png/resource=divelements.sandribbon.resources.defaultimage.png/resource =divelements.sandribbon.resources.exit.png/resource=divelements.sandribbon.resources.furtheroptions.png/ Resource=divelements.sandribbon.resources.help.png/resource= Divelements.sandribbon.resources.messages.resources/resource=divelements.sandribbon.resources.options.png/ Resource=divelements.sandribbon.ribbon.png/resource=divelements.sandribbon.ribbonmanager.png/resource= Divelements.sandribbon.statusbar.png/resource=divelements.sandribbon.toolbar.png/resource= Divelements.sandribbon.x1818ca8d87654aad.resources/out:divelements. Sandribbon.dll/dll

Then you can use it. As for the online download DLL is really limited .... I'm still not clear about it. Because to see how Microsoft realizes the license. More trouble.

Reference documents:

Http://www.cnblogs.com/jianggest/archive/2009/05/04/ldc.html

Http://www.cnblogs.com/midea0978/articles/81072.html

Research and crack of licensing and authorization