KrNews #09 18 мая 1999

Программирование

Protection - The problems of security and hacking programs.

    Problems of protection and cracking PROGRAMS


 (C) ALS'99

 The eternal problem of software - is the protection of its
software products from hacking and copying ... On this subject 
was written a sufficient number of articles and therefore

I will tell about the main methods.
 It started when there were only
the first defense. Then I had a vague idea of ​​protection and 
poorly understood in assembler. But when sales began to defend 
their drives me is not so arranged. Now when you buy the disc 
or I, nor my friends could not overwrite

program.
 At first it was difficult to understand, had to pay money for 
ANTIPROTECTory, but then the costs were justified. Personally

I have finalized a few defenses, but the latter no copyist and 
not copies, and antizaschitu write on it is not simple, and all 
because it uses method RND.


 Tip: always when writing PROTECTora
Use the RND, to the defense
Each new disc information encoded on the new key.

 Well, I'll write a couple of tips. Most
the main problem - is that your boot loader has been completely 
protected from the key Magic (@) is when it is clicked the 
program simply discharged or made more that either.

 Next - is that your BASIC loader was well protected from 
viewing. At this time, they protect rather

cool and easy to use even STSa
may not help if you do not know how
protection works. All blocks must raskodirovatsa the end of the 
address and up with hacking into their most difficult to break, 
so also occur in the protection team such as flip LDIR when one 
byte is thrown at himself, and eventually changes for 
themselves. Example: 

40000 # 18

            XXXX-no relevant information
40010 LD HL, 40000

            LD DE, 40001

            LD BC, 114
40019 # EDBO LDIR

            XXXX-no relevant information

 Let's look at this program. Everything is clear and
understandable, but it's what you think! With the transfer of 
power will make the team LDIR transfer of bytes to the address 
and replace the code 40019 # ED on the number of which is in 
the HL, in this case, the number of # 18 and we already have in 
this area addresses is a team not LDIR and JR 39941 and the 
program jumps to that address. If use of STS in debug mode you

do not get why think for yourself.
 There are more options when you need to
drive is not switched off, otherwise
If a program hangs or is not decoded properly.
 Perhaps this has everything, because y
I absolutely do not have enough time to
further the story, but I think that the
write the following number for more information how to make and 
break. 

time 23.33.10
date 23.04.99 Especially for KrNews


                          Hacker Als