Is AES-CBC decryption independent of the number of rounds that was used during the encryption process? 0.o?
On Sun, Mar 17, 2013 at 10:04 AM, Ewen Chan <[email protected]> wrote: > Curious question - still more about AES and CBC and openssl: > > Does the number of rounds during the encryption phase of it have to > match the number of rounds during the decryption phase of it, or does > it not matter? (i.e. the "rounds" count really only matters during the > encryption-only phase, and for decryption; it is independent of it)? > > On Sat, Mar 16, 2013 at 11:33 PM, Ewen Chan <[email protected]> wrote: >> I was just curious, cuz other people have spelled it that way as well. >> And I just wanted to be sure. Thanks. >> >> On Sat, Mar 16, 2013 at 11:29 PM, <[email protected]> wrote: >>> Congrats! you caught my typing error. >>> Steven J. Hathaway >>> >>>> Thanks. >>>> >>>> Is the name spelt Rijndael or Rijndahl? >>>> >>>> On Sat, Mar 16, 2013 at 8:15 PM, <[email protected]> wrote: >>>>> AES/Rijndahl >>>>> >>>>> AES has fixed number of rounds and other parameters. >>>>> Rijndahl allows you to specify the algorithm parameters including number >>>>> of rounds. >>>>> >>>>> Steven J. Hathaway >>>>> >>>>>> So is the number of rounds set by Rijndahl or the AES spec? I'm >>>>>> confused. >>>>>> >>>>>> And is the number of rounds hard-coded into the OpenSSL source; or is >>>>>> it embedded somewhere else? >>>>>> >>>>>> On Fri, Mar 15, 2013 at 7:27 PM, <[email protected]> wrote: >>>>>>> I don't know the interfaces to OpenSSL, but AES-192 specifies the >>>>>>> number >>>>>>> of rounds. The approved AES algorithms specify a subset of Rijndahl >>>>>>> cipher whereby you can specify alternative numbers of rounds, key >>>>>>> sizes, and block sizes. >>>>>>> >>>>>>> Sincerely, >>>>>>> Steven J. Hathaway >>>>>>> >>>>>>>> There's a file that I want to encrypt using AES-192-CBC but with 19 >>>>>>>> rounds rather than the default 12-rounds. >>>>>>>> >>>>>>>> Is there a way for me to specify the number of rounds that I would >>>>>>>> like to use with the AES-192-CBC? (and override the algorithm >>>>>>>> defaults)? >>>>>>>> >>>>>>>> Is that something that I can within the openssl command itself (to >>>>>>>> encrypt a file) or is the process much more involved than that? And >>>>>>>> requires programming/scripting? >>>>>>>> ______________________________________________________________________ >>>>>>>> OpenSSL Project >>>>>>>> http://www.openssl.org >>>>>>>> User Support Mailing List >>>>>>>> [email protected] >>>>>>>> Automated List Manager >>>>>>>> [email protected] >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> >>>>>>> ______________________________________________________________________ >>>>>>> OpenSSL Project http://www.openssl.org >>>>>>> User Support Mailing List [email protected] >>>>>>> Automated List Manager [email protected] >>>>>> ______________________________________________________________________ >>>>>> OpenSSL Project http://www.openssl.org >>>>>> User Support Mailing List [email protected] >>>>>> Automated List Manager [email protected] >>>>>> >>>>>> >>>>> >>>>> >>>>> ______________________________________________________________________ >>>>> OpenSSL Project http://www.openssl.org >>>>> User Support Mailing List [email protected] >>>>> Automated List Manager [email protected] >>>> ______________________________________________________________________ >>>> OpenSSL Project http://www.openssl.org >>>> User Support Mailing List [email protected] >>>> Automated List Manager [email protected] >>>> >>>> >>> >>> >>> ______________________________________________________________________ >>> OpenSSL Project http://www.openssl.org >>> User Support Mailing List [email protected] >>> Automated List Manager [email protected] ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List [email protected] Automated List Manager [email protected]
