在2014年，Tsai等人提出基於動態載入之Android App防複製攻擊機制，使用者須通過身分鑑別取得並解密App執行時所需的相關資源檔才可執行App完整功能，進而達到防制App遭受複製攻擊的目的。然而，此機制無法有效鑑別使用者身分的正確性，即無法抵禦授權使用者分享其個人相關鑑別資訊，以供非授權使用者通過身分鑑別，進而取得執行App所需的資源檔。因此，本研究基於橢圓曲線密碼系統、不可否認簽章及簽密法，設計出抵禦App複製攻擊之機制，透過不可否認簽章於驗證簽章有效性時須透過簽署者合作的特性，確保僅有授權使用者得以通過身分鑑別取得資源檔執行完整功能。本機制亦可達到鑑別性(authenticity)、完整性(integrity)、機密性(confidentiality)、不可偽造性(unforgeability)、不可否認性(non-repudiation)、雙向鑑別性(mutual authentication)、抵抗重送攻擊(replay attack resistance)及抵抗中間人攻擊(man-in-the-middle attack resistance)等安全需求。最後，本研究結果不但可用以防制App遭受非授權複製與散佈攻擊，並同時可以達到降低運算複雜度與通訊成本之目的。

The concept of copy protection mechanism based on dynamic loading for android application was proposed by Tsai, Chiu and Wu in 2014. To prevent the application suffering unauthorized copy and distribute, when unauthorized users obtain the application installation file, they must pass the authentication or they can’t execute application fully function. However, this mechanism cannot effectively authenticate the correctness of the user identity that cannot resist the authorized users to share their personal identification information to unauthorized users. Therefore, we adopt undeniable signature to withstand application clone attack to ensure that only authorized users can pass the authentication to obtain the application resource files to execute application fully function. In our proposed method can achieve authenticity, integrity, confidentiality, non-repudiation, mutual authentication resistance, replay attack resistance, man-in-the-middle attack resistance. Finally, this method can be used to withstand the application suffering unauthorized copy and distribute attack, and can also reduce complexity of computation and communication costs.

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