Hi Biswa, what machine architecture are you using? ie a pentium (32-bit) or a usparc or alpha (64-bit) ?
cheers, Sean biswatosh chakraborty wrote: > Hi > While dealing on RSAKeyGen I accidentally discovered a set of numbers > for which BN_mod_exp is giving a wrong result. I want to know whether I > am wrong or even if my code is right, is there some limitation to > BN_mod_exp? > I am interested to calculate (x^y)mod z by using BN_mod_exp(r,x,y,z) > where the result is stored in r. I used openssl-0.9.6 downloaded from > the openssl site two days back. > I will give here the values of x,y,z and r in hex. Could anybody please > throw some light on the seemingly wrong result? > x = 3 > y = 2DC6C0 > z = > > >01000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000035691B3FEC50B2AC41174CE60E220E2A33D4791F07BD4039644FE27C02617E1F50A252B6E0F4731BCD0811FB88E5C392338251EA4A63ECAA08CCC6447BC1446D0B8020D98AEE85A4BFEA2353A0268464FD68F0C4224FB011C2F3067C97E2B6C0F91D0F242D1BBACAD3C598481804420C546A0816F4CE5575F7F9B472BDD81FB1949 > > > > > r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nd when I used a large integer calculator and gmp library as well, I > found that both gmp and the calculator were giving the same reult but of > course different from ssl .ssl's output is in the varaible r ,given above. > gmp and the calculator gave the below number: > > 0176B344F2A78C0000 > > Now,I went to the ssl BIGNUM code and found that for odd modulus, it > executes montogomery and for even it uses BN_mod_exp_simple. If you use > simple for all cases it gives slow but correct result but montogomery > seems to fail in case of some odd modulus like in the present case. > Any idea please? > bye > > Thanks > Biswa > > > _________________________________________________________________ > Join the world?s largest e-mail service with MSN Hotmail. > http://www.hotmail.com > > ______________________________________________________________________ > 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]
