You are conflating the act of debugging with the operation of a "debugger".
Sure you can start at 0 and step forward one instruction at a time, but how often do you do that without at least looking at the code?
Not being able to look ahead or behind but only within what is actively on the stack is certainly a limiting factor in debugging.
It is of course a problem that has been solved before. Someone would develop an unpacker/decrypter for it at some point and make this trivial, but that would still be an added level of complexity.
I agree. I'm not sure I understand your point though. This isn't contrary to anything I said. I mention unpacking which would be a pre-debugger process.
I believe you are just being pedantic about my use of the word "debugging" to include things like unpacking, static analysis, and a variety of tools and processes used.
The binaries aren't preencrypted here, the dynamic nature is the whole point. There's nothing to unpack since you just reference the binary, and no added work for the debugger.
So when you say
> For example it appears to combat ROP they are additionally encrypting the code segment of the program and decrypting on an as needed basis. I am absolutely sure this would make debugging more difficult.
Just for an example. How about debugging a non trivial issue between a program and a dynamically loaded library.
You can't just scan the IAT/PLT. You are going to have to find load points or manually step through, and maybe calculate function offsets in the library. Not impossible at all.
It is however something you could have just quickly glanced at and found otherwise.
Sure you can start at 0 and step forward one instruction at a time, but how often do you do that without at least looking at the code?
Not being able to look ahead or behind but only within what is actively on the stack is certainly a limiting factor in debugging.
It is of course a problem that has been solved before. Someone would develop an unpacker/decrypter for it at some point and make this trivial, but that would still be an added level of complexity.