Simple implementation of xor dynamic encryption assembly code

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The simple implementation of XOR dynamic encryption first of all, I would like to express my special thanks to Yan binlang's great guidance to me.

Then, simply put, the code is followed by comments, which should be detailed! 4-byte Encryption

The efficiency is good. In a loopd loop, an exclusive or encrypted Key is added with 2, so that each 4 bytes is converted into an exclusive or value.

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Pushad // all registers into the stack

Call xxxxxxxx // The Next line of code in CALL is pop ebx.

Pop ebx // an EBX pop-up stack

Sub ebx, xxxxxxxx // xxxxxxxx represents the memory address of the last row, that is, the pop ebx row (before the relocation)

Add ebx, xxxxxxxx // xxxxxxxx indicates the address before the feature is relocated.

Mov ecx, 5 // 5 cycles

Mov edx, 12345678 // pass 12345678 to EDX as the initialization KEY of the first loop

Mov eax, dword ptr [ebx] // transfers the memory location of ebx to eax

Xor eax, edx // encrypt the result of XOR encryption between EDX and EAX in EAX

Mov dword ptr [ebx], eax // transfers encrypted content to ebx

Add ebx, 4 // The memory address of ebx plus 4 bytes

Add edx, 2 // dynamically encrypt the edx value plus 2 cycles plus 2 at a time

Loopd short xxxxxxxx // jump to mov eax, dword ptr [ebx]. This is a loop. The number of loops is shown in the figure above. 5 indicates 5 loops.

Popad // all register fetch Stack

Original jmp entry point // jump to the original entry point