If I'm right Fooler is located in other part of the world. F2F won't be a possibility for him I guess. Unfortunately Doc Pab (sorry), I'm in the hospital so, chat session is viable in this case (concall via Skype?). I have my laptop and probably just hook it up in the Wifi are then. Or I'll try to be there @ 2PM.
Thanks, Mike ________________________________ From: Pablo Manalastas <[email protected]> To: Philippine Linux Users' Group (PLUG) Technical Discussion List <[email protected]> Sent: Thursday, July 16, 2009 10:26:51 AM Subject: Re: [plug] Code Review & SysAdmin of Election 2010 Computers Fooler, Are you coming to the F2F on Saturday at the CenPEG office? Please come. And please everyone who is interested come to the meeting. Thanks. //PManalastas --- On Thu, 7/16/09, fooler mail <[email protected]> wrote: > From: fooler mail <[email protected]> > Subject: Re: [plug] Code Review & SysAdmin of Election 2010 Computers > To: "Philippine Linux Users' Group (PLUG) Technical Discussion List" > <[email protected]> > Date: Thursday, July 16, 2009, 9:44 AM > On Thu, Jul 16, 2009 at 8:18 AM, > Michael Tinsay<[email protected]> > wrote: > >> From: Rage Callao <[email protected]> > >> > >> 2009/7/13 Pablo Manalastas : > >> > >> > We can suggest to Comelec to compute SHA1 or > MD5 checksums of the approved > >> programs, and at election time, the checksums can > be recomputed (manually) and > >> if the original checksum and new checksum agree, > then there is no substitution. > >> > >> > >> AFAIR, SHA1 and MD5SUM have been broken. > > > > > > While there is still the probability of collission, > what is the possibility that such can be used to "falsely > validate" the data and programs that will be used for the > election? > > > > here is how digital signature works... > > for signing at precinct level... > > 1) ER = election return digital document > > 2) hashvalue = MD5_or_SHA1(ER) > > 3) signvalue = ENCRYPT(hashvalue, privatekey) > > send ER + signvalue to comelec server... > > the signvalue above is the encrypted hashvalue of ER > document using > the signer's privatekey.. signvalue is now the digital > signature of ER > document... > > for validating or verifying at canvasser level... > > a) hashvalue1 = DECRYPT(signvalue, publickey) > > b) hasvalue2 = MD5_or_SHA1(ER) > > c) compare hashvalue1 to hashvalue2.. if equal then > authentic... > otherwise bogus.. > > as you can see... hash function or message digest such as > MD5 or SHA1 > is not important here and whether it is collision prone or > not for > sending ERs... what important here is the privatekey > encrypting the > hash value of ER documents... once a cheater got a copy of > BEI's > privatekey without passphrase protection... he can create > its own ER > and signs it... > > take note also for manual election.. vote buying was > rampant.. for > automated election.. privatekey buying is going to happen > aside from > vote buying :-> > > but for smartmatic program to test its authenticity... we > need a > higher message digest such as SHA2 family (eg. SHA256, > SHA384, SHA512) > to avoid collision as the comelec is the one signing > smartmatic > program... they can create another program (the cheated > one) padded > some bytes just to have the same hash value with the > orignal program > (collision) and signs it... > > fooler. > _________ _________________________________________________ Philippine Linux Users' Group (PLUG) Mailing List http://lists.linux.org.ph/mailman/listinfo/plug Searchable Archives: http://archives.free.net.ph
_________________________________________________ Philippine Linux Users' Group (PLUG) Mailing List http://lists.linux.org.ph/mailman/listinfo/plug Searchable Archives: http://archives.free.net.ph
