Part 17 - ROR Instruction

For a complete table of contents of all the lessons please click below as it will give you a brief of each lesson in addition to the topics it will cover. https://github.com/mytechnotalent/Reverse-Engineering-Tutorial

The ROR command stands for rotate right.

In our simple x64 example on an Ubuntu Linux machine above we see we mov 1 into al and rotate right by 1 bit.

The binary representation is 00000001b. If we ROR 1 bit the value simply becomes 10000000b as demonstrated below.

We first compile and link by:

nasm -f elf64 -o test.o test.asm

ld -o test test.o

We can see here in the debugger that al starts with 1 and when we rotate right it goes to 10000000b.

Next week we will dive into Boot Sector Basics! Stay tuned!