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Title: | 針對有限精度單峰映射影像加密演算法之圖神經網路參數迴歸攻擊 A GNN Based Parameter Regression Attack on Image Encryption Algorithm Using Logistic Map under Finite Precision Constraints |
Authors: | Wen-Cheng Tsou 鄒汶橙 |
Advisor: | 吳家麟(Ja-Ling Wu) |
Keyword: | 混沌映射,有限精度,圖神經網路,參數迴歸, Chaotic maps,Finite precision,Graph neural network,Parameter regression, |
Publication Year : | 2022 |
Degree: | 碩士 |
Abstract: | 混沌映射性近幾年被廣泛應用在密碼學上,主要仰賴其確定性、非週期性、及對初始值的敏感性。而在影像加密的領域中,混沌映射更是被套用為在空間域中的加密元件,使其成為一種偽隨機亂數生成器(PRNG)。跟傳統的影像加密方法相比,這種加密方式提供的最大好處是不會讓密文檔案大小過度膨脹,並且能提供極高速的加密速度,在現今要求即時多媒體應用的需求下,混沌映射是非常好的解藥。在此論文中,我們提出了一種以圖神經網路為基底的攻擊手法,透過針對特定混沌映射,在有限精度下設計的先備知識訓練集,預訓練出一個能夠迴歸參數的圖神經網路模型。攻擊時我們假設攻擊者能夠竊聽到一部分的混沌序列,並將該序列輸入模型進行迴歸,進而推導出出該混沌序列所對應到的參數,此參數在影像加密演算法中即相當於金鑰。換言之,若此法順利迴歸出混沌序列之參數,則表示攻擊(或破密)成功 Owing to their deterministic, nonperiodic, and sensitive to initial state characteristics, chaotic maps are widely applied to cryptography in recent years. In chaos-based image encryption schemes, chaotic maps behave like a pseudo random number generator for encrypting digital images in the spatial domain. Contrary to traditional methods, the major advantage of chaos-based image encryption algorithm is its high encrypt speed and limited size expansion of the cipherimage. Thanks to this advantages, chaos-based image encryption algorithm has become a great remedy in real-time secure multimedia application areas nowadays. In this work, by designing a flexible and novel algorithm to generate appropriate training set based on the domain knowledge of specific chaotic maps in finite precision and pre-training a Graph Neural Network model for conducting parameters regressions, a GNN based parameter regression attack is proposed. To launch the attack, we assume that attacker has ability to eavesdrop a portion of the chaotic sequence, and the captured sequence segment is then input to the pre-tarined model we mentioned above for getting the corresponding parameter. The obtained parameter is equivalent to the key in a chaos-based image encryption algorithm. If the parameter can be found by the network, we say the attack is successful. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/86569 |
DOI: | 10.6342/NTU202201736 |
Fulltext Rights: | 同意授權(全球公開) |
metadata.dc.date.embargo-lift: | 2022-08-31 |
Appears in Collections: | 資訊工程學系 |
Files in This Item:
File | Size | Format | |
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U0001-2607202216052200.pdf | 2.26 MB | Adobe PDF | View/Open |
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