從大量數位簽章中找出不合法簽章之研究

數位簽章被廣泛運用在網路的環境，作為數位訊息的驗證。而近年來，有許多應用例如：電子投票、車載通訊，需要在短時間內去驗證多個數位簽章，因此批次驗證被提出。若大量簽章中有少數個不合法的簽章，而一個一個驗會花費許多時間。我們利用批次驗證的特性，試著從大量的簽章中找出不合法的簽章，。然而，有些惡意的攻擊者針對某些不完善的簽章機制可以製造出對的簽章但無意義的信息或試圖產生一群在批次驗證時可以通過但其實個別都是違法的簽章。過去被提出的批次驗證方法包括DSA、RSA 或BLS，我們將其分類適合多個簽暑者或單一簽屬者。對於一群在批次驗證時可以通過但其實個別都是違法簽章攻擊，小指數測試在1998 年被提出用來測試整批的簽章中是否有不合法的簽章存在，但仍然無法有效地找出不合法的簽章。在我們的論文中，提出了訊息格式驗證方法，成功在RSA 簽章系統中解決攻擊者製造對的簽章但不具有對的格式信息的攻擊。另外，我們也提出了一個編碼演算法有效的識別出不合法的簽章，也成功的解決兩兩簽章結合在一起能通過驗證但個別為違法簽章的攻擊。然而，當兩兩簽章在偵測中造成cycle的困難，我們也提出了解決辦法。因此，我們的方法可以有效的解決任何以兩兩簽章結合在一起而通過驗證但個別為不合法簽章的問題。

關鍵字

數位簽章；批次驗證；不合法簽章；小指數測試；訊息格試驗證；編碼演算法

並列摘要

Digital signatures are used for authentication of digital messages. Many signatures need to be verified in short time in some applications like E-voting or Vehicle to Communication, so batch verification is proposed. If there are some illegal signatures among lots of signatures, it costs a lot by verifying individually. We use the property of batch verification to detect illegal signatures among massive signatures, the verifier verifies a batch of signatures at one time instead of verifying individually. We classify what signature scheme is suitable for multi signers and what is suitable for the same signer. However, some malicious parties forge a valid signature but has no meaningful message in uncomplete signature scheme or a group of pseudo-valid signatures which can pass batch verification but in fact are all invalid individually. For the pseudo-valid signatures, small exponents test was proposed to check whether if invalid signatures exist or not, but fails to identify the invalid ones. In our thesis, we propose a method called Numbering which can identify illegal signatures and successfully solves the two-pseudo-valid signatures set that has minimum degree one in graph like path and tree. We also propose format check scheme which successfully avoids the illegal signature that is a valid signature but without a correct format message in RSA.

並列關鍵字

Digital Signature ； Batch verification ； Small Exponent test ； Illegal Signatures ； Format Check ； Numbering Algorithm

參考文獻

[1] W. Kempton, J. Tomic, Vehicle-to-grid power fundamentals: calculating capacity and net revenue, J. Power Sources vol. 144, pp. 268 - 279, 2005.

[2] W. Kempton, J. Tomic, Vehicle-to-grid power mplementation: from stabilizing the grid to supporting large-scale renewable energy, J.Power Sources vol. 144 pp.

280 - 294, 2005.

[4] L. Law, B.J. Matt, Finding invalid signatures in pairing-based batches, in Crytography and Coding, 11th IMA international Conference, ed. by S.D. Galbraith. Lecture Notes in Computer Science, vol. 4887, pp. 34 - 53. Springer, Berlin, 2007.

[5] Yi-Li Huang, Chu-Hsing Lin, and Fang-Yie Leu, Veri cation of a Batch of Bad Signatures by using the Matrix-Detection Algorithm, in 2011 First International Conference on Data Compression, Communications and Processing, pp. 299-306, IEEE, 2011.

國際替代計量

從大量數位簽章中找出不合法簽章之研究

全文下載

主題瀏覽