On Mon, 24 Feb 2014 14:25:40 +0100 Ben RUBSON <ben.rub...@gmail.com> wrote: | 2014-02-24 1:20 GMT+01:00 Anthony Thyssen <a.thys...@griffith.edu.au>: | | To be sure that all IOs of one file will be aligned, does the encryption of | 4K of data give exactly 4K of encrypted data ? | encryption happens in 'blocks of data'. If the data encrypted in is less a block in size it increases to that block size.
So encrytped files will grow but only 'encrypt block units'. This is also why EncFS filenames are all specific lengths. For example... here are two such filenames. and all filenames in a EncFS directory were of these two lengths. IEMVj6vUghdkoz,zruQQUgBa J8uZKvdQWREdaO,ML5301SwgYSOAkjywjAc9ZFon7jnL40 The first was a short filename, the second a longer filename. However the filename length is also made longer as the binary encryption is base64 (a sligh varient of) encoded with a 16 bit MAC added to the front. EG: filename -> block encrypted a 16 bit MAC pre-pended and converted to ASCII format using base64 varient. The first filename was one encryption block, the second needed two encryption blocks to hold the longer filename. Anthony Thyssen ( System Programmer ) <a.thys...@griffith.edu.au> -------------------------------------------------------------------------- Light thinks it travels faster than anything, but it is wrong. No matter how fast light travels, it finds the darkness always got there first, and it is waiting for it. -- Terry Pratchett, "Reaper" -------------------------------------------------------------------------- Anthony's Castle http://www.ict.griffith.edu.au/anthony/ ------------------------------------------------------------------------------ Flow-based real-time traffic analytics software. Cisco certified tool. Monitor traffic, SLAs, QoS, Medianet, WAAS etc. with NetFlow Analyzer Customize your own dashboards, set traffic alerts and generate reports. Network behavioral analysis & security monitoring. All-in-one tool. http://pubads.g.doubleclick.net/gampad/clk?id=126839071&iu=/4140/ostg.clktrk _______________________________________________ Encfs-users mailing list Encfs-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/encfs-users
