PUOKMS: Password-Protected Updatable Oblivious Key Management System for Cloud Storage

Updatable oblivious key management system (UOKMS) has been widely applied in reality to protect outsourced data confidentiality. We demonstrate that existing UOKMS fails prevent users’ private information from being leaked. show an adversary can impersonate any user access her/his sensitive UOKMS, and this problem is further exacerbated by the collusion between two entities (i.e., a server cloud server). In paper, we propose secure two-layered encryption mechanism resist impersonation attacks. Specifically, first layer public/secret generated user’s password via way, where hardened set of dedicated identity servers thwart guessing attacks; besides, multiple secretly share user-specific server-side for each assist generating second symmetric key. also utilize renewal periodically updates secret on perpetual leakage secret. With these mechanisms, develop password-protected updatable storage, dubbed PUOKMS. evaluate PUOKMS terms security efficiency, which demonstrates achieves strong guarantee with high efficiency.