On Wed, Aug 15, 2012 at 10:12:27AM -0500, Kent Yoder wrote: > Hi Arno, > > >> > >> This appears to work (no message printed, exit status 0). > >> > >> What might not be obvious is that if binary_secret contains a '\n' > >> character, input gets truncated at this point. > > > > This is documented in the man-page of the current release under > > "NOTES ON PASSPHRASE PROCESSING FOR LUKS". > > You were right - I was looking at an old git version. The new > version is clearer IMO. Ok. > >> This should probably be clearer in the man page at a > >> minimum (see patch), but I think a warning is appropriate too. > >> Secret processing that stops at \n isn't appropriate for binary > >> data. > > > > And that is the thing here. A passphrase is _not_ binary data! > > Doing > > > > "cat binary_secret | cryptsetup luksFormat /dev/loop0" > > > > is inherently wrong. What you need to do is > > > > "cat file_with_passphrase_that_could_also_be_entered_interactively > > | cryptsetup luksFormat /dev/loop0" > > I agree - just seeing a script that did the first one made me wonder > if it even worked. Well, people have to read the documentation if they want it to work right. It is really not that much for cryptsetup, just the man-page plus the FAQ. It is not like it has a 500 page documentation. If people ignore the documentation, they basically get what they deserve. This problem is worse with crypto, as lots of problems are non-visible (it works but is insecure), but anybody working with crypto needs to understand that. Those that do not _will_ make fatal mistalkes, no matter how much warning is given. Crypto is not a beginners game. > > As to your patch, I am unable to match your patch to the > > current version of the man-page. Did you do a "git pull" > > before? May also be a problem on my side, please verify: > > > >> md5sum cryptsetup.8 > > 4fd70bbd1018f95818902144499c2234 cryptsetup.8 > > Yep, I am out of date here. What do you think about a code change > that woudl print a big fat warning if non-ascii bytes are detected on > stdin? Not changing the behavior (we don't want to break people who > might be already doing this), but just a warning. See my reply to Milan. Arno -- Arno Wagner, Dr. sc. techn., Dipl. Inform., Email: arno@xxxxxxxxxxx GnuPG: ID: 1E25338F FP: 0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F ---- One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision. -- Bertrand Russell _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt
