death's "electric-camel"

[difficulty: 6][protection: tiger,sha1,blowfish,el-gamal]


It does some sha/tiger/blowfish which has to produce the right el-gamal private key to decrypt the goodboy message. See solution and keygen for details. The hardest thing about this crackme is the message of c++ code that goes along with crypto++ library. There's just so much code. I downloaded an old compiler and service pack in order to build the two versions of crypto++ that straddle the 2001 time that this crackme was made, and produced IDA signatures from these.

One of the coolest thing to be learned from this crackme is just how fast MAGMA can solve the DLP for this crackme:

P: cc7346a8b4ffb3f2393b
G: 00000000000000000003
Y: 3e2cb006ad3961beda9d

I left alpertron on overnight and it had not found anything... About 17 hours of computation was continuing when Dcoder from EFNET #cryptography helped me his script:

p := 965489229592273293031739;
K := GF(p);
g := K ! 3;
y := K ! 293611062693023723739805;
x := Log(g, y);
x;

It finds x=0792A1952223 in about .3 seconds!