5 ms·

Furball: The Linux Equivalent of DOS's 'debug.com'

23 points by asciilifeform 17y ago

tptacek 17y ago
Funny you should mention that. Timur, Chris, and I have been puttering around with a better Unix debugger interface for awhile now; Timur just wrote some of it up: http://www.matasano.com/log/1799/ruby-for-pentesters-the-dark-side-i-ragweed/ http://www.matasano.com/log/1799/ruby-for-pentesters-the-dar... Debuggers want to be programming environments. Or, trivial 20k command line programs. GDB is stuck uncomfortably in the middle, I agree.
- kragen 17y ago
  Or both. Did Nirva ever tell you the story of when he entered the ACM programming contest and wrote his entries in debug.com?
- mahmud 17y ago
  I have seen "symdeb for linux" as early as 1999; there was an entire symbdeb clone somewhere in simtel, written in NASM (or an early precursor, don't remember) and the author was bugging alt.asm.x86 for quite sometime, reporting his progress. Boldyshev might have an idea, if he is still at it.
lallysingh 17y ago
Some stupid debug tricks: a 0100 cli jmp 0101 r Clears interrupts and puts the CPU into an infinite loop. Takes down Win95/98 cold. Thankfully NT+ don't actually give DOS programs control over interrupts. ? 0100 (I forget which cmd lets you directly edit the memory in hex) ea 00 00 ff ff r Quick reboot. The malicious will think of fun places to put this. Hint: rhymes with "soot vector" Sometimes I wonder if the greatest loss when technology shifts are all the stupid tricks we learned on the way.
- whughes 17y ago
  A few years ago, I was in a tech support call with a Dell tech. He was putting me through some kind of reinstallation process, I don't recall exactly. Anyway, he actually had me boot from a Dell diagnostic CD, run debug.com, and type in the necessary commands to hard-format the drive. At the time, I thought the whole process was pretty novel. I wonder if they would do the same today.
- cturner 17y ago
  I'd love to see a longer list of debug tricks like this. I've for _First Steps in 80286 Assembly_ and understand the theory, but I find it's easier to learn by example.

23 points by asciilifeform 17y ago

Funny you should mention that. Timur, Chris, and I have been puttering around with a better Unix debugger interface for awhile now; Timur just wrote some of it up: http://www.matasano.com/log/1799/ruby-for-pentesters-the-dark-side-i-ragweed/ http://www.matasano.com/log/1799/ruby-for-pentesters-the-dar... Debuggers want to be programming environments. Or, trivial 20k command line programs. GDB is stuck uncomfortably in the middle, I agree.

kragen 17y ago
Or both. Did Nirva ever tell you the story of when he entered the ACM programming contest and wrote his entries in debug.com?
mahmud 17y ago
I have seen "symdeb for linux" as early as 1999; there was an entire symbdeb clone somewhere in simtel, written in NASM (or an early precursor, don't remember) and the author was bugging alt.asm.x86 for quite sometime, reporting his progress. Boldyshev might have an idea, if he is still at it.

lallysingh 17y ago

Some stupid debug tricks: a 0100 cli jmp 0101 r Clears interrupts and puts the CPU into an infinite loop. Takes down Win95/98 cold. Thankfully NT+ don't actually give DOS programs control over interrupts. ? 0100 (I forget which cmd lets you directly edit the memory in hex) ea 00 00 ff ff r Quick reboot. The malicious will think of fun places to put this. Hint: rhymes with "soot vector" Sometimes I wonder if the greatest loss when technology shifts are all the stupid tricks we learned on the way.

whughes 17y ago
A few years ago, I was in a tech support call with a Dell tech. He was putting me through some kind of reinstallation process, I don't recall exactly. Anyway, he actually had me boot from a Dell diagnostic CD, run debug.com, and type in the necessary commands to hard-format the drive. At the time, I thought the whole process was pretty novel. I wonder if they would do the same today.
cturner 17y ago
I'd love to see a longer list of debug tricks like this. I've for _First Steps in 80286 Assembly_ and understand the theory, but I find it's easier to learn by example.