Example 3

Assembly Language Tutorial

Please choose a tutorial page: Fundamentals -- Information about C Tools Registers Simple Instructions Example 1 -- SC CDKey Initial Verification Example 2 -- SC CDKey Shuffle Example 2b -- SC CDKey Final Decode The Stack Stack Example Functions Example 3 -- Storm.dll SStrChr Assembly Summary Machine Code Example 4 -- Smashing the Stack Cracking a Game Example 5 -- Cracking a game Example 6 -- Writing a keygen .dll Injection and Patching Memory Searching Example 7 -- Writing a cheat for Starcraft (1.05) Example 7 Step 1 -- Displaying Messages Example 7 Step 1b -- Above, w/ func ptrs Example 7 Final Example 8 -- Getting IX86.dll files 16-bit Assembly Example 9 -- Keygen for a 16-bit game Example 10 -- Writing a loader

                 push    ebp
                 mov     ebp, esp
                 mov     eax, [ebp+arg_0]
                 test    eax, eax
                 jnz     short loc_1

                 push    57h             ; dwErrCode
                 call    ds:SetLastError
                 xor     eax, eax
                 pop     ebp
                 retn    8
 ; ---------------------------------------------------------------------------

 loc_1:
                 mov     cl, [eax]
                 test    cl, cl
                 jz      short loc_3
                 mov     dl, [ebp+arg_4]
                 jmp     short loc_2
 ; ---------------------------------------------------------------------------

 loc_2:
                 cmp     cl, dl
                 jz      short loc_4
                 mov     cl, [eax+1]
                 inc     eax
                 test    cl, cl
                 jnz     short loc_2

 loc_3:
                 xor     eax, eax

 loc_4:
                 pop     ebp
                 retn    8