4 ms·

The manual page mentions that the program has a command that will calculate the "approximate storage capacity of a file", but doesn't really say what that would

The manual page mentions that the program has a command that will calculate the "approximate storage capacity of a file", but doesn't really say what that would be. I'm guessing that would turn out to be the limiting factor here—it seems like you'd either need a really long text file, or a really short encrypted message to be able to use this method reliably.

ballenf 8y ago
I'd guess the idea would be to pass around a copy of Hamlet, the Odyssey, Canterbury Tales, KJV Bible[1], or a similar public domain lengthy and popular work that would, in itself, draw no attention to itself. For me, the reason I always hesitated to use widespread encryption ahead of mainstream adoption was that standing out as an oddity seemed to pose a greater threat than taking no extraordinary efforts. That is, if I engaged in behavior similar to someone with good reason to hide then I might become a target for scrutiny. My "opsec" wouldn't have been effective for anything beyond casual scrutiny, so my security efforts would have been demonstrably counter-productive[1]. At least that was my logic. A couple examples: as soon as full disk encryption started shipping with Windows, I used it. When choosing between SMS, Hangouts, and iMessage, I'd choose iMessage. Not saying my logic was sound, but feel confident that it contains at least a degree of truth. [1] Sort of an all-or-nothing choice. Taking some steps arguably makes you a higher profile requiring consistent security measures taken at every turn.
- kardos 8y ago
  > I'd guess the idea would be to pass around a copy of <snip> Diffing your copy of Hamlet.txt against a clean copy would reveal the pattern of spaces (ie, the cyphertext), so the security by obscurity (if any) would be easily defeated.
  - crpatino 8y ago
    First, let me say that encoding bits in whitespace is to Steganography what ROT13 is to Cryptography. Neither has a chance of success against any non-incompetent attacker, but they serve well as simple proofs of concept. Second, you assume there's one canonical Hamlet.txt to compare against (which there's, if Alice was dumb enough to pick whatever is the first available option in Guthenberg.org as her cover message). For a more sophisticated attack, you must consider how many different editions, reprints, etc, have there been of that work over the centuries. For each of those, you must consider how many possible digitalizations can be obtained for different brands and configurations of scanners. Then, there's the issue that you must do all of this for every large message that Internet users send to each other...

ballenf 8y ago

I'd guess the idea would be to pass around a copy of Hamlet, the Odyssey, Canterbury Tales, KJV Bible[1], or a similar public domain lengthy and popular work that would, in itself, draw no attention to itself. For me, the reason I always hesitated to use widespread encryption ahead of mainstream adoption was that standing out as an oddity seemed to pose a greater threat than taking no extraordinary efforts. That is, if I engaged in behavior similar to someone with good reason to hide then I might become a target for scrutiny. My "opsec" wouldn't have been effective for anything beyond casual scrutiny, so my security efforts would have been demonstrably counter-productive[1]. At least that was my logic. A couple examples: as soon as full disk encryption started shipping with Windows, I used it. When choosing between SMS, Hangouts, and iMessage, I'd choose iMessage. Not saying my logic was sound, but feel confident that it contains at least a degree of truth. [1] Sort of an all-or-nothing choice. Taking some steps arguably makes you a higher profile requiring consistent security measures taken at every turn.

kardos 8y ago
> I'd guess the idea would be to pass around a copy of <snip> Diffing your copy of Hamlet.txt against a clean copy would reveal the pattern of spaces (ie, the cyphertext), so the security by obscurity (if any) would be easily defeated.
- crpatino 8y ago
  First, let me say that encoding bits in whitespace is to Steganography what ROT13 is to Cryptography. Neither has a chance of success against any non-incompetent attacker, but they serve well as simple proofs of concept. Second, you assume there's one canonical Hamlet.txt to compare against (which there's, if Alice was dumb enough to pick whatever is the first available option in Guthenberg.org as her cover message). For a more sophisticated attack, you must consider how many different editions, reprints, etc, have there been of that work over the centuries. For each of those, you must consider how many possible digitalizations can be obtained for different brands and configurations of scanners. Then, there's the issue that you must do all of this for every large message that Internet users send to each other...