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Old 2017-09-19, 03:45   #12
crack11
 
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SIR ,

any algo use to solve this issu..
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Old 2017-09-19, 11:48   #13
crack11
 
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Dear all exparts.

Please help me to calculate GCD ...
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Old 2017-09-19, 12:32   #14
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Quote:
Originally Posted by crack11 View Post
Dear all exparts.

Please help me to calculate GCD ...
find some other software if you think it's so easy and plug it in there's many computer algebra systems.

Last fiddled with by science_man_88 on 2017-09-19 at 13:17
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Old 2017-09-19, 14:11   #15
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Old 2017-09-19, 17:36   #16
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Quote:
Originally Posted by crack11 View Post
Dear all im new in this Greatest forum i have problem in mathe matica i need calculat

...
As you have subsequently clarified, this problem arises from a desire to solve a particular 512-bit RSA system. By far the easiest way known to approach this one is to factor the public modulus. A 512-bit integer factorization is not yet trivial but it is straightforward with current technology.

Post the public modulus and why you want it factored (that is, what does the key protect?) and a number of people here could solve your problem. I certainly could. Remember: just because they can doesn't mean they will. In other words, what's in it for me? Why should I divert resources from the things which presently interest me?

Of course, I've already diverted resources, my time, in posting the above but I regard that as a relatively small but speculative investment which may yield a worthwhile return.
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Old 2017-09-19, 21:46   #17
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Originally Posted by Dr Sardonicus View Post
Ditto.
No goblins or sock puppets either.
Leprechauns, unicorns, good fairies and wizards unite.
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Old 2017-09-20, 03:04   #18
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Quote:
Originally Posted by xilman View Post
Post the public modulus and why you want it factored (that is, what does the key protect?) and a number of people here could solve your problem. I certainly could. Remember: just because they can doesn't mean they will. In other words, what's in it for me? Why should I divert resources from the things which presently interest me?
It looks to me, from the numbers posted above, that they know the plaintext/ciphertext pairs, but doesn't know the N, and the gcd is supposed to give the N? Weird.
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Old 2017-09-20, 13:28   #19
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Z1:= (7580104959982914109394378405621081680045277328933902877018950173722431866047182165909685701898461476201769271496346873969218041590426190558248064238412-(5542744080416549313204339685348101804092633280776996094712323671936025724303663565120968650288374354487920966943136994524637343823470109069100536001825061^65537));
Z2:= (7580104959982914109394378405621081680045277328933902557064898247755957479231576299665165903124564064889635003580310606233252493957322555511313835652894-(2210052959863233666352631743605544948489669349588589762935731382353706272687862251429121203091727087209430630578779213774169437578222468020592099358198793^65537));
Z3:= (7580104959982914380707737866198974081289603526426728444663905520185161944615556517456155284414829089801734045676331442459189567878379004868410811939884-(7769917532858189300573807160645252136211403803199106971490637897656073492246460627329132405022210291064618462659663590068082649667914372368725493336150572^65537));
ToUpperCase[IntegerString[(GCD[Z1,Z2,Z3]),16]]

ruselt512:BDDA237EB5F92257D6D114DA2F28FB442A1EE793813902905374CCF24F2DE4AA3560931BB8718B3EA665AEDBC7FE20AB30293BF85765E72695A7A085513B547B
this string give rsa 512

Last fiddled with by crack11 on 2017-09-20 at 13:30
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Old 2017-09-20, 17:32   #20
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Quote:
Originally Posted by crack11 View Post
ruselt512:BDDA237EB5F92257D6D114DA2F28FB442A1EE793813902905374CCF24F2DE4AA3560931BB8718B3EA665AEDBC7FE20AB30293BF85765E72695A7A085513B547B
this string give rsa 512
Thank you. We are able to make progress.

Now, why is this particular public modulus of interest? I ask because it isn't included in my, admittedly small, collection of interesting moduli nor can I find it on the web with a quick and simple search.

Last fiddled with by xilman on 2017-09-20 at 17:44 Reason: Add last sentence
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Old 2017-09-20, 21:13   #21
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I've got some other questions:

1) Why does this procedure involve taking the gcd of three integers?

2) Why are the integers of the form a - b^p, for a prime p? (I can think of some possible reasons, but I'm not at all sure.)

I was able to verify that your hex string does represent a 512-bit integer that does divide the three integers in your second example. In decimal, this integer is

9943361511736887180525193238781951852048704466124378491895895799799940176852818360584496466538746226491733937270575629104317392858375709260953122655392891

I checked that it is composite, and it has no small factors.
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Old 2017-09-21, 02:54   #22
crack11
 
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Dear xilman sir.

this is a cryptoworks smartcards rsa string but new string and old same just plaintext change ciphertext same and exp change new is very big and mathematica show problem to start kindly help me to solve this issu please solve this string any other app like matlab or mapel maybe you solve this :
(7580104959982914123117804044806461820154572036369549529405552162648856956231245030405896783337631871321017085933334306430501343909365379890910193903441-(7601611438277968963930435339966375537762723788929138241505092335032216337024111944145650540579951639515460945444623092013993572866002842083492323809287290^17592186175489));
Z2:= (7580104959982914123117804044806461820154572036369549301773204651044654156328611994019678602790933052049997074737942147009504600337458372628655015658163-(5472021051232020294637156058031796107019454396525172260491306567922450488302345750910648307191204110931670031994886144725045972546892458995859985546716414^17592186175489));
Z3:= (7580104959982914050609440727680305970398447676033232174897745114621599628756001756455762578505630805317234747401759098214730033873908508468766892578356-(2716401471494295676405217606243925186946305783849093640906079739928627393562677984831598246598185728284424287135181309232467496805930321500988187816347957^17592186175489));
ToUpperCase[IntegerString[(GCD[Z1,Z2,Z3]),16]] this is new exp string
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