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sector address as the IV. IVs don't need to be random, secret, or unpredictable - they just need to be unrepeated. (I'm assuming sector-at-a- time encryption). If the IV is not a secret how are we going to prevent block replay attacks on cipher text? Regards Sarath. --- Peter Gutmann <[EMAIL PROTECTED]> wrote: > "Trei, Peter" <[EMAIL PROTECTED]> writes: > [EMAIL PROTECTED]:[EMAIL PROTECTED] > >>"Trei, Peter" <[EMAIL PROTECTED]> writes: > >>>with a good distribution of IVs > >> > >>Where would you store them? The feature of this > is that it's fully > >>transparent, so you can't store IVs anywhere. > > > >I'm not really up on crypto file systems, but I > beleive at least some use the > >sector address as the IV. IVs don't need to be > random, secret, or > >unpredictable - they just need to be unrepeated. > (I'm assuming sector-at-a- > >time encryption). > > But the IV is repeated, every time you encrypt new > data for that sector. You > need to either store a random IV for each sector > (usually infeasible) or make > two passes over the data (details vary), using the > output from pass 1 to > affect pass 2 (slow). > > >>>* Some kind of PIN or password protection on the > dongle. > >> > >>How would you do this without a custom BIOS > (remember that their general > >>product is for dropping into any PC)? > > > >We're talking about two different products. The > ABIT is a MB, presumably with > >it's own custom BIOS, so that's not an issue there. > > Customised, not custom. Think of it as a > Chinese-menu type setup, it's a one- > size-fits-all BIOS with appropriate modules compiled > in for handling the CPU > and chipset features. Now motherboard vendors can > plug in their own feature > modules, but it's a somewhat nontrivial option > usually used only for highly > marketable features (overclocking options, ability > to re-flash from Windows, > etc etc). > > Peter. > > > __________________________________ > Do you Yahoo!? > Yahoo! SiteBuilder - Free, easy-to-use web site > design software > http://sitebuilder.yahoo.com __________________________________ Do you Yahoo!? Yahoo! SiteBuilder - Free, easy-to-use web site design software http://sitebuilder.yahoo.com