Improved GPU Implementation of RainbowCrack

Rainbow table is one of the techniques to crack passwords from hash values by precomputation table. However, password cracking takes much time in the case of long password. Accelerators such as GPGPUs will reduce time spent on cracking for long passwords. Rainbow Crack is a password cracking software program which implements rainbow table. Rainbow Crack uses reduction function, table compression and GPU implementation. This paper proposes a new reduction function, a table compression technique and their GPU implementation on GeForce GTX 670. As a result, it becomes 17.6% faster than RainbowCrack, and memory size of precomputation table can be decreased by 23.0%.