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Dropbox: The Inside Story Of Tech's Hottest Startup

forbes.com

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Re: Dropbox: The Inside Story Of Tech's Hottest Startup

#51

Post by scott_s »

JonnieCache wrote: post #26
rkudeshi wrote: post #20

Earlier quoted context omitted.

I had no idea installing Dropbox meant they were modifying the Finder. Why isn't there an option to disable this?

Note that they are injecting code into the running Finder process, which is very different from patching the Finder binary. That would be very bad.

I'm not convinced that patching code into a running process [1] is any better than patching the binary on disk. That's the sort of thing that a fully secured system would not allow.

[1] Of course excluding programs that have an actual plugin interface, and the "patching" just constitutes using that interface.

Re: Dropbox: The Inside Story Of Tech's Hottest Startup

#52

Post by codemechanic »

dr_ wrote: post #15

Jobs never changed his interpretation of things. He did in fact feel cloud storage was a feature and not a product, and that's exactly what iCloud is. For Apple it's a feature that will hopefully tie people in to their iOS devices. And with the likelihood that over time they will offer greater amounts of storage for free or a minimum payment, that's not good for Dropbox. I like Dropbox, I use it almost daily. But so…

Dropbox also faces competition from products like TonidoSync (http://www.tonido.com/app_sync_home.html) that allows you to use your own hardware as sync server.

Before anybody jumps on me- Yes. Tonido does support all the OSes- Windows, Mac and Linux. They have mobile apps for all the popular mobile platforms - iOS, Android, Win 7 and Blackberry. It also works on ARM powered NAS devices and supports webdav as well.

In short, one can use their mac mini or home pc as sync server or buy one of those plug devices (www.tonidoplug.com) that runs 24/7 consuming just 1 watt/hr.

Re: Dropbox: The Inside Story Of Tech's Hottest Startup

#53

Post by JonnieCache »

simplekoala wrote: post #50
JonnieCache wrote: post #26

Earlier quoted context omitted.

Note that they are injecting code into the running Finder process, which is very different from patching the Finder binary. That would be very bad.

They are injecting code into running Finder process? Hmmm, so they figured one of the jump instructions target address in Finder process ( for a function invocation, most likely the code to show the pop-up), and changed that location to jump to a different address where they injected their code? Don't you need root privileges to muck with Finder's process space? I see dropbox process running with non-privileged uid.…

I think there are some hooks in OSX/Cocoa for doing this, although I don't claim to actually understand it.

There is the SIMBL system which people used to write native plugins for Safari, I guess that's probably stopped since it has an actual extension framework now.

http://www.culater.net/software/SIMBL/SIMBL.php

Then there's TotalFinder, which uses in-memory patching to add tabs and all sorts of other leet stuff into Finder. I highly recommend it. In their docs they say it works similarly to SIMBL.

http://totalfinder.binaryage.com/

Re: Dropbox: The Inside Story Of Tech's Hottest Startup

#54

Post by vrikhter »

channelmeter wrote: post #35
keithpeter wrote: post #24

2 gig free, next step up is 50Gb. Anyone else find the big jump means they use the dropbox just for day to day projects? A 10 or 20 Gig price point at $5 a month would be something I could rationally use.

Agreed. I always wished Dropbox had a lower, entry-level tier for around $5/month. I don't need 50gb. I just need 5-10gb.

This is totally self serving (http://news.ycombinator.com/item?id=3126173). If you're on the free plan, you should be able to max out your referrals at somewhere between 8-10GB of free space for you (they may have lowered it). I got 30 referrals for less than $10....give it a shot, I've had friends try this recently and they didn't end up spending more than $15.

Re: Dropbox: The Inside Story Of Tech's Hottest Startup

#55

Post by johnrob »

luigi wrote: post #9

Then come Chris, Jason and Joe (who has a Dropbox tattoo on his arm because he feels “Drew is changing the world”), more MIT brothers aiming to live a California dream they all imagined back in Cambridge as “billionaires, bottles and babes.” Eww, that's offputting.

I don't find it offputting; I think it's expected:

http://en.wikipedia.org/wiki/Maslow%27s_hierarchy_of_needs

Re: Dropbox: The Inside Story Of Tech's Hottest Startup

#56

Post by scott_s »

simplekoala wrote: post #50
JonnieCache wrote: post #26

Earlier quoted context omitted.

Note that they are injecting code into the running Finder process, which is very different from patching the Finder binary. That would be very bad.

They are injecting code into running Finder process? Hmmm, so they figured one of the jump instructions target address in Finder process ( for a function invocation, most likely the code to show the pop-up), and changed that location to jump to a different address where they injected their code? Don't you need root privileges to muck with Finder's process space? I see dropbox process running with non-privileged uid.…

A process can't change the address space of another process, period. Even if one is a root process. Separation of address spaces is a basic security service provided by the operating system. So I'm also puzzled how they are able to modify memory in Finder's address space.

The closest thing I can think of is that Finder executes arbitrary processes on behalf of the user. That is, when I double click on something, Finder has to do the fork-exec dance to launch that application. A process fork, however, creates an entirely separate address space for the new process. I would be shocked if Finder did not do that. So, yes, I'm also wondering what it is they do.

Re: Dropbox: The Inside Story Of Tech's Hottest Startup

#57

Post by bostonvaulter2 »

gr366 wrote: post #3

Does Forbes.com have a print URL? I couldn't find one (did find a print.css which does almost nothing to optimize for printing), and I'd rather not encourage their splitting the article onto 4 separate pages by clicking through.

Works find in readability. This link might work for you:

http://www.readability.com/articles/giut9xtb

Re: Dropbox: The Inside Story Of Tech's Hottest Startup

#58

Post by scott_s »

JonnieCache wrote: post #53
simplekoala wrote: post #50

Earlier quoted context omitted.

They are injecting code into running Finder process? Hmmm, so they figured one of the jump instructions target address in Finder process ( for a function invocation, most likely the code to show the pop-up), and changed that location to jump to a different address where they injected their code? Don't you need root privileges to muck with Finder's process space? I see dropbox process running with non-privileged uid.…

I think there are some hooks in OSX/Cocoa for doing this, although I don't claim to actually understand it. There is the SIMBL system which people used to write native plugins for Safari, I guess that's probably stopped since it has an actual extension framework now. http://www.culater.net/software/SIMBL/SIMBL.php Then there's TotalFinder, which uses in-memory patching to add tabs and all sorts of other leet stuff in…

So, hijacking shared libraries. I doubt they're actually changing the Finder process in memory. I bet their changes are localized to the library they hijack.

Re: Dropbox: The Inside Story Of Tech's Hottest Startup

#59

Post by simplekoala »

JonnieCache wrote: post #53
simplekoala wrote: post #50

Earlier quoted context omitted.

They are injecting code into running Finder process? Hmmm, so they figured one of the jump instructions target address in Finder process ( for a function invocation, most likely the code to show the pop-up), and changed that location to jump to a different address where they injected their code? Don't you need root privileges to muck with Finder's process space? I see dropbox process running with non-privileged uid.…

I think there are some hooks in OSX/Cocoa for doing this, although I don't claim to actually understand it. There is the SIMBL system which people used to write native plugins for Safari, I guess that's probably stopped since it has an actual extension framework now. http://www.culater.net/software/SIMBL/SIMBL.php Then there's TotalFinder, which uses in-memory patching to add tabs and all sorts of other leet stuff in…

Thanks for the info. On further digging, I found this useful link - http://www.culater.net/wiki/moin.cgi/CocoaReverseEngineering

which provides some insights into accomplishing what Dropbox did.

Re: Dropbox: The Inside Story Of Tech's Hottest Startup

#60

Post by simplekoala »

scott_s wrote: post #56
simplekoala wrote: post #50

Earlier quoted context omitted.

They are injecting code into running Finder process? Hmmm, so they figured one of the jump instructions target address in Finder process ( for a function invocation, most likely the code to show the pop-up), and changed that location to jump to a different address where they injected their code? Don't you need root privileges to muck with Finder's process space? I see dropbox process running with non-privileged uid.…

A process can't change the address space of another process, period. Even if one is a root process. Separation of address spaces is a basic security service provided by the operating system. So I'm also puzzled how they are able to modify memory in Finder's address space. The closest thing I can think of is that Finder executes arbitrary processes on behalf of the user. That is, when I double click on something, Find…

Thanks for the clarification. I was thinking may be they were mucking with shared libraries. I found this useful link on digging further. Doesn't seem like too much of black art. http://www.culater.net/wiki/moin.cgi/CocoaReverseEngineering
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