6 ms·

ODA - Online Disassembler

50 points by jazzdan 14y ago

tptacek 14y ago
Looks like it's objdump built for all-architectures.
- gsg 14y ago
  Certainly has some of objdump's quirks. 8d bc 27 00 00 00 00 => lea 0x0(%edi,%eiz,1),%edi. I was half expecting a disassembler written in Javascript.
SparrowOS 14y ago
I made a disassembler It's mostly just a binary search through the opcodes. The trick is ordering them. http://www.sparrowos.com/Wb/Compiler/Unassembler.html http://www.sparrowos.com/Wb/Compiler/Unassembler.html Yes, I typed all this shit by hand. It's not complete. http://www.sparrowos.com/Wb/Compiler/OpCodes.html http://www.sparrowos.com/Wb/Compiler/OpCodes.html
kanzure 14y ago
It would be great to be able to paste a url to others of a work-in-progress pastebin-style dump of something I'm commenting or reversing. Also, symfiles.
- adotout 14y ago
  This is actually a feature we're currently working on. Thanks for reinforcing the need.
unwind 14y ago
Fantastic feature to show branches graphically in the margin as arrows. Blindingly obvious, but still saves a lot of mental effort in keeping addresses in your head. Haven't seen any "desktop disassembler" (that sounds furniture-related) do that.
- borski 14y ago
  IDA Pro shows branches/jumps as a graph, which I think is even better: http://www.hex-rays.com/products/ida/pix/5_plain_graph_view.gif http://www.hex-rays.com/products/ida/pix/5_plain_graph_view.... When not in graph mode, it'll show jump arrows in the margin: http://www.chip.de/ii/146940129_e98df3e41d.jpg http://www.chip.de/ii/146940129_e98df3e41d.jpg
  - wladimir 14y ago
    IDA Pro is crazily expensive though, and probably not worth it unless you're doing reverse engineering / exploit finding for a living. For example it's a bit overkill for just looking at disassembly to see what code the compiler has written, which (I think) is the common use case of objdump.
    - anigbrowl 14y ago
      That's true, and it seems to bog down easily in my (limited) experience with it. Ollydbg is fast and free, and very navigable. http://www.ollydbg.de/ http://www.ollydbg.de/ Oh, it too has arrows. That's what I mean by navigable. 32 bit only though.
      - StavrosK 14y ago
        From my limited experience with OllyDbg, it was fantastic.
      - tptacek 14y ago
        Ollydbg has more or less given way to Immunity Debugger, which is what you should be checking out if that's the flavor of reversing tool you're after. I don't know a lot of people who use IDA as a debugger and like it. On the other hand, IDA's a better disassembler (and not just because it handles multiple architectures) than Olly. It's the industry standard for a good reason. Hopper.app is giving it a run for its money on x86 and ARM. Hopper is all I use now. I think it's ironic that people think IDA is too expensive; it's not expensive enough, given its total addressable market. IDA's prices are so low that they artificially depress the market for all reverse engineering tools, which anchor or orbit around IDA's price point. Hex-Rays is trying to break out of that with the decompiler, but then Hopper did a good-enough decompiler and bundled it into a $100 tool. Professionals that use IDA (a) rely on it heavily (b) can use the same version of IDA for years and years (c) routinely bill out over 250-300/hr and (d) number in the tens of thousands. It's an interesting business case study.
anigbrowl 14y ago
For those who don't have showdead enabled... SparrowOS 2 hours ago | link [dead] | -26% I made a disassembler It's mostly just a binary search through the opcodes. The trick is ordering them. http://www.sparrowos.com/Wb/Compiler/Unassembler.html http://www.sparrowos.com/Wb/Compiler/Unassembler.html Yes, I typed all this shit by hand. It's not complete. http://www.sparrowos.com/Wb/Compiler/OpCodes.html http://www.sparrowos.com/Wb/Compiler/OpCodes.html -- I haven't really gotten to grips with SparrowOS yet as I don't program enough to fully understand/appreciate it, but this makes it that bit more desirable as a hacking tool. Thank you.
- tptacek 14y ago
  He wrote a disassembler as a hand-hacked state machine. A crazy amount of focus. "-26%"?
  - anigbrowl 14y ago
    FeelHN does sntiment analysis for HN posts - I find it a useful indicator that it might be time to step away from a particular discussion or take a break from HN. https://chrome.google.com/webstore/detail/feelhn/hpnealkfodhijkldoeigafncbllcbnbg https://chrome.google.com/webstore/detail/feelhn/hpnealkfodh...
iseyler 14y ago
The site barfs when I upload the BareMetal OS kernel for disassembly. Is there a size limit? The kernel is x86-64 and only 16KiB in size.
- adotout 14y ago
  No, it's just an immature website. I'm one of the creators. The site is just a hobby now among friends, and since we all have families, it's slow going. Thanks for the feedback everyone!

50 points by jazzdan 14y ago

tptacek 14y ago

Looks like it's objdump built for all-architectures.

gsg 14y ago
Certainly has some of objdump's quirks. 8d bc 27 00 00 00 00 => lea 0x0(%edi,%eiz,1),%edi. I was half expecting a disassembler written in Javascript.

SparrowOS 14y ago

I made a disassembler It's mostly just a binary search through the opcodes. The trick is ordering them. http://www.sparrowos.com/Wb/Compiler/Unassembler.html http://www.sparrowos.com/Wb/Compiler/Unassembler.html Yes, I typed all this shit by hand. It's not complete. http://www.sparrowos.com/Wb/Compiler/OpCodes.html http://www.sparrowos.com/Wb/Compiler/OpCodes.html

kanzure 14y ago

It would be great to be able to paste a url to others of a work-in-progress pastebin-style dump of something I'm commenting or reversing. Also, symfiles.

adotout 14y ago
This is actually a feature we're currently working on. Thanks for reinforcing the need.

unwind 14y ago

Fantastic feature to show branches graphically in the margin as arrows. Blindingly obvious, but still saves a lot of mental effort in keeping addresses in your head. Haven't seen any "desktop disassembler" (that sounds furniture-related) do that.

borski 14y ago
IDA Pro shows branches/jumps as a graph, which I think is even better: http://www.hex-rays.com/products/ida/pix/5_plain_graph_view.gif http://www.hex-rays.com/products/ida/pix/5_plain_graph_view.... When not in graph mode, it'll show jump arrows in the margin: http://www.chip.de/ii/146940129_e98df3e41d.jpg http://www.chip.de/ii/146940129_e98df3e41d.jpg
- wladimir 14y ago
  IDA Pro is crazily expensive though, and probably not worth it unless you're doing reverse engineering / exploit finding for a living. For example it's a bit overkill for just looking at disassembly to see what code the compiler has written, which (I think) is the common use case of objdump.
  - anigbrowl 14y ago
    That's true, and it seems to bog down easily in my (limited) experience with it. Ollydbg is fast and free, and very navigable. http://www.ollydbg.de/ http://www.ollydbg.de/ Oh, it too has arrows. That's what I mean by navigable. 32 bit only though.
    - StavrosK 14y ago
      From my limited experience with OllyDbg, it was fantastic.
    - tptacek 14y ago
      Ollydbg has more or less given way to Immunity Debugger, which is what you should be checking out if that's the flavor of reversing tool you're after. I don't know a lot of people who use IDA as a debugger and like it. On the other hand, IDA's a better disassembler (and not just because it handles multiple architectures) than Olly. It's the industry standard for a good reason. Hopper.app is giving it a run for its money on x86 and ARM. Hopper is all I use now. I think it's ironic that people think IDA is too expensive; it's not expensive enough, given its total addressable market. IDA's prices are so low that they artificially depress the market for all reverse engineering tools, which anchor or orbit around IDA's price point. Hex-Rays is trying to break out of that with the decompiler, but then Hopper did a good-enough decompiler and bundled it into a $100 tool. Professionals that use IDA (a) rely on it heavily (b) can use the same version of IDA for years and years (c) routinely bill out over 250-300/hr and (d) number in the tens of thousands. It's an interesting business case study.

anigbrowl 14y ago

For those who don't have showdead enabled... SparrowOS 2 hours ago | link [dead] | -26% I made a disassembler It's mostly just a binary search through the opcodes. The trick is ordering them. http://www.sparrowos.com/Wb/Compiler/Unassembler.html http://www.sparrowos.com/Wb/Compiler/Unassembler.html Yes, I typed all this shit by hand. It's not complete. http://www.sparrowos.com/Wb/Compiler/OpCodes.html http://www.sparrowos.com/Wb/Compiler/OpCodes.html -- I haven't really gotten to grips with SparrowOS yet as I don't program enough to fully understand/appreciate it, but this makes it that bit more desirable as a hacking tool. Thank you.

tptacek 14y ago
He wrote a disassembler as a hand-hacked state machine. A crazy amount of focus. "-26%"?
- anigbrowl 14y ago
  FeelHN does sntiment analysis for HN posts - I find it a useful indicator that it might be time to step away from a particular discussion or take a break from HN. https://chrome.google.com/webstore/detail/feelhn/hpnealkfodhijkldoeigafncbllcbnbg https://chrome.google.com/webstore/detail/feelhn/hpnealkfodh...

iseyler 14y ago

The site barfs when I upload the BareMetal OS kernel for disassembly. Is there a size limit? The kernel is x86-64 and only 16KiB in size.

adotout 14y ago
No, it's just an immature website. I'm one of the creators. The site is just a hobby now among friends, and since we all have families, it's slow going. Thanks for the feedback everyone!