Christopher C. Lamb, Pramod A. Jamkhedkar, Mathew P. Bohnsack, Viswanath Nandina, G. Heileman
In this paper we describe the development of a domain specific language (DSL) for expressing usage management policies and associating those policies with managed artifacts. We begin by framing a model for the language, including generalized use cases, a domain model, a general supported life-cycle, and specific extension requirements. We then develop the language from that model, demonstrating key syntactic elements and highlighting the technology behind the language while tracing features back to the initial model. We then demonstrate how the DSL supports common usage management and DRM-centric environments, including creative commons, the extensible rights markup language (XrML), and the open digital rights language (ODRL).
{"title":"A domain specific language for usage management","authors":"Christopher C. Lamb, Pramod A. Jamkhedkar, Mathew P. Bohnsack, Viswanath Nandina, G. Heileman","doi":"10.1145/2046631.2046641","DOIUrl":"https://doi.org/10.1145/2046631.2046641","url":null,"abstract":"In this paper we describe the development of a domain specific language (DSL) for expressing usage management policies and associating those policies with managed artifacts. We begin by framing a model for the language, including generalized use cases, a domain model, a general supported life-cycle, and specific extension requirements. We then develop the language from that model, demonstrating key syntactic elements and highlighting the technology behind the language while tracing features back to the initial model. We then demonstrate how the DSL supports common usage management and DRM-centric environments, including creative commons, the extensible rights markup language (XrML), and the open digital rights language (ODRL).","PeriodicalId":124354,"journal":{"name":"ACM Digital Rights Management Workshop","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122803471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The success or failure of digital rights management is often taken in legal circles to be a technological question: has a particular scheme already been cracked? How broadly is protected content being redistributed? Can any scheme provide absolute security for content? By these measures, DRM, at least in its most visible applications, has been a failure, as has its legal bulwark, the Digital Millennium Copyright Act. Most widely available schemes are cracked within a few years of release. And due to the nature of the Internet, breaking a scheme once means it is broken everywhere. Under these conditions, absolute security is both required and impossible. This is the so-called "Darknet" hypothesis, first described at the ACM-DRM workshop nine years ago. But the success or failure of DRM and anticircumvention policy generally is also a legal question, or more properly, a question about how law and technology interact with society. Assessing DRM's success therefore requires first determining its place in a copyright landscape that is undergoing a fundamental transformation. That transformation can be described simply as a disappearance of gates. Copyright relies on a world that makes copying without permission costly and difficult. That is, it relies on natural choke points at which access to content can be traded for money. Those natural choke points, or "gates," are disappearing. DRM is an attempt to reestablish a sort of gate, and its success or failure in any given application depends on how well it mimics the real-world gates it is replacing. And that is primarily a social question, not a technological one. Furthermore, it indicates a different set of threats to DRM schemes, and to the policy embodied in the DMCA: to the extent such schemes visibly interfere with common uses, their viability as replacement gates is diminished. The gravest threat to DRM schemes may come not from a particular sophisticated attack, but rather from a dissipation of the illusion of naturalness.
{"title":"Is DRM working?: how could we tell?","authors":"Bruce E. Boyden","doi":"10.1145/2046631.2046633","DOIUrl":"https://doi.org/10.1145/2046631.2046633","url":null,"abstract":"The success or failure of digital rights management is often taken in legal circles to be a technological question: has a particular scheme already been cracked? How broadly is protected content being redistributed? Can any scheme provide absolute security for content? By these measures, DRM, at least in its most visible applications, has been a failure, as has its legal bulwark, the Digital Millennium Copyright Act. Most widely available schemes are cracked within a few years of release. And due to the nature of the Internet, breaking a scheme once means it is broken everywhere. Under these conditions, absolute security is both required and impossible. This is the so-called \"Darknet\" hypothesis, first described at the ACM-DRM workshop nine years ago.\u0000 But the success or failure of DRM and anticircumvention policy generally is also a legal question, or more properly, a question about how law and technology interact with society. Assessing DRM's success therefore requires first determining its place in a copyright landscape that is undergoing a fundamental transformation. That transformation can be described simply as a disappearance of gates. Copyright relies on a world that makes copying without permission costly and difficult. That is, it relies on natural choke points at which access to content can be traded for money.\u0000 Those natural choke points, or \"gates,\" are disappearing. DRM is an attempt to reestablish a sort of gate, and its success or failure in any given application depends on how well it mimics the real-world gates it is replacing. And that is primarily a social question, not a technological one. Furthermore, it indicates a different set of threats to DRM schemes, and to the policy embodied in the DMCA: to the extent such schemes visibly interfere with common uses, their viability as replacement gates is diminished. The gravest threat to DRM schemes may come not from a particular sophisticated attack, but rather from a dissipation of the illusion of naturalness.","PeriodicalId":124354,"journal":{"name":"ACM Digital Rights Management Workshop","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114609773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fingerprinting codes are mechanisms to increase the security of transaction watermarking. Digital transaction watermarking is an accepted mechanism to discourage illegal distribution of multimedia. Here copies of the same content are distributed with individual markings. Simple but effective attacks on transaction watermarking are collusion attacks where multiple individualized copies of the work are compared in order to detect and attack the watermark positions and thus create a counterfeited watermark. One common countermeasure is given by fingerprinting codes. The main challenge is to provide codes which are highly secure, reliable and, at the same time, provide a sufficiently compact code length according to the payload limitations of current watermarking algorithms. Applying such codes in practice, the codes have to face additional challenges: Most operators arrogate small amounts of time for the code generation and embedding process and for the detection and accusation process. In this article, we describe a new fast but fair fingerprinting code to detect a collusion of up to three colluders. The code is very flexible and consciously kept simple to be adaptive and fast in order to stay applicable for all demands of potential appliers. Using accusation sums we are able to make a decision about which kind of attack strategy the colluders may have used. Accordingly the algorithm is split into two different tracing strategies. Both are based on discarding as many fingerprints as possible and only consider the most suspicious.
{"title":"Fast and adaptive tracing strategies for 3-secure fingerprint watermarking codes","authors":"Marcel Schäfer, Waldemar Berchtold, M. Steinebach","doi":"10.1145/2046631.2046640","DOIUrl":"https://doi.org/10.1145/2046631.2046640","url":null,"abstract":"Fingerprinting codes are mechanisms to increase the security of transaction watermarking. Digital transaction watermarking is an accepted mechanism to discourage illegal distribution of multimedia. Here copies of the same content are distributed with individual markings. Simple but effective attacks on transaction watermarking are collusion attacks where multiple individualized copies of the work are compared in order to detect and attack the watermark positions and thus create a counterfeited watermark.\u0000 One common countermeasure is given by fingerprinting codes. The main challenge is to provide codes which are highly secure, reliable and, at the same time, provide a sufficiently compact code length according to the payload limitations of current watermarking algorithms. Applying such codes in practice, the codes have to face additional challenges: Most operators arrogate small amounts of time for the code generation and embedding process and for the detection and accusation process.\u0000 In this article, we describe a new fast but fair fingerprinting code to detect a collusion of up to three colluders. The code is very flexible and consciously kept simple to be adaptive and fast in order to stay applicable for all demands of potential appliers. Using accusation sums we are able to make a decision about which kind of attack strategy the colluders may have used. Accordingly the algorithm is split into two different tracing strategies. Both are based on discarding as many fingerprints as possible and only consider the most suspicious.","PeriodicalId":124354,"journal":{"name":"ACM Digital Rights Management Workshop","volume":"177 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134160852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Digital rights management (DRM) of integrated circuits (ICs) is a crucially important task both economically and strategically. Several IC metering techniques have been proposed, but until now their effectiveness for royalty management has not been quantified. IC auditing is an important DRM step that goes beyond metering; it not only detects that a pirated IC has been produced but also determines the quantity of pirated ICs. Our strategic objective is to create a new intrinsic passive metering technique as well as the first IC auditing technique, and to maximize and quantify their effectiveness using statistical analysis and IC characterization techniques. Our main technical innovations include physical level gate characterization, a Bayesian approach for coincidence analysis, and an adaptation of animal counting techniques for IC production estimation. We evaluate the accuracy of the IC metering and auditing approach using simulations on a set of ISCAS benchmarks.
{"title":"Integrated circuit digital rights management techniques using physical level characterization","authors":"Sheng Wei, F. Koushanfar, M. Potkonjak","doi":"10.1145/2046631.2046635","DOIUrl":"https://doi.org/10.1145/2046631.2046635","url":null,"abstract":"Digital rights management (DRM) of integrated circuits (ICs) is a crucially important task both economically and strategically. Several IC metering techniques have been proposed, but until now their effectiveness for royalty management has not been quantified. IC auditing is an important DRM step that goes beyond metering; it not only detects that a pirated IC has been produced but also determines the quantity of pirated ICs. Our strategic objective is to create a new intrinsic passive metering technique as well as the first IC auditing technique, and to maximize and quantify their effectiveness using statistical analysis and IC characterization techniques. Our main technical innovations include physical level gate characterization, a Bayesian approach for coincidence analysis, and an adaptation of animal counting techniques for IC production estimation. We evaluate the accuracy of the IC metering and auditing approach using simulations on a set of ISCAS benchmarks.","PeriodicalId":124354,"journal":{"name":"ACM Digital Rights Management Workshop","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116590663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper considers the problem of converting an encryption scheme into a scheme in which there is one encryption process but several decryption processes. Each decryption process is made available as a protected software implementation (decoder). So, when some digital content is encrypted, a legitimate user can recover the content in clear using its own private software implementation. Moreover, it is possible to trace a decoder in a black-box fashion in case it is suspected to be an illegal copy. Our conversions assume software tamper-resistance.
{"title":"Traitor tracing schemes for protected software implementations","authors":"M. Joye, Tancrède Lepoint","doi":"10.1145/2046631.2046636","DOIUrl":"https://doi.org/10.1145/2046631.2046636","url":null,"abstract":"This paper considers the problem of converting an encryption scheme into a scheme in which there is one encryption process but several decryption processes. Each decryption process is made available as a protected software implementation (decoder). So, when some digital content is encrypted, a legitimate user can recover the content in clear using its own private software implementation. Moreover, it is possible to trace a decoder in a black-box fashion in case it is suspected to be an illegal copy. Our conversions assume software tamper-resistance.","PeriodicalId":124354,"journal":{"name":"ACM Digital Rights Management Workshop","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122004903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A patient-centric DRM approach is proposed for protecting privacy of health records stored in a cloud storage based on the patient's preferences and without the need to trust the service provider. Contrary to the current server-side access control solutions, this approach protects the privacy of records from the service provider, and also controls the usage of data after it is released to an authorized user.
{"title":"A rights management approach to protection of privacy in a cloud of electronic health records","authors":"Mohammad Jafari, R. Safavi-Naini, N. Sheppard","doi":"10.1145/2046631.2046637","DOIUrl":"https://doi.org/10.1145/2046631.2046637","url":null,"abstract":"A patient-centric DRM approach is proposed for protecting privacy of health records stored in a cloud storage based on the patient's preferences and without the need to trust the service provider. Contrary to the current server-side access control solutions, this approach protects the privacy of records from the service provider, and also controls the usage of data after it is released to an authorized user.","PeriodicalId":124354,"journal":{"name":"ACM Digital Rights Management Workshop","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131653941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
From a ciphertext and a secret key assigned to a user, the decryption of a Chameleon encryption scheme produces a message which is the plaintext embedded with a watermark associated to the user. Most existing constructions of Chameleon encryption scheme are LUT (lookup table)-based, where a secret LUT plays the role of the master key and each user has a noisy version of the secret LUT. LUT-based methods have the limitation that the secrecy of the master key, under known-plaintext attack (KPA), relies on the difficulty in solving large linear system. In other words, with some knowledge of the plaintext, a dishonest user is able to derive the LUT, or an approximation of the LUT by solving a linear system. Resistance to such attack is crucial in the context of multimedia encryption since multimedia objects inherently contain high redundancies. Furthermore, for efficiency in decryption, the underlying linear system is likely to be sparse or not overly large, and hence can be solved using reasonable computing resource. In our experiment, a desktop PC is able to find a LUT (with 216 entries) within 2 hours. We propose a scheme that is resistant to KPA. The core of the scheme is a MUTABLE-PRNG (Pseudo Random Number Generator) whereby different but similar sequences are generated from related seeds. We generate such sequence from multiple pseudo random sequences based on majority-vote, and enhance its performance using error-correcting code. The proposed scheme is very simple and it is easy to show that it is resistant to KPA under reasonable cryptographic assumptions. However, it is not clear how much information on the original plaintext is leaked from the watermarked copies. We analyze the scheme and quantify the information loss using average conditional entropy.
{"title":"A chameleon encryption scheme resistant to known-plaintext attack","authors":"E. Chang, Chengfang Fang, Jia Xu","doi":"10.1145/1866870.1866876","DOIUrl":"https://doi.org/10.1145/1866870.1866876","url":null,"abstract":"From a ciphertext and a secret key assigned to a user, the decryption of a Chameleon encryption scheme produces a message which is the plaintext embedded with a watermark associated to the user. Most existing constructions of Chameleon encryption scheme are LUT (lookup table)-based, where a secret LUT plays the role of the master key and each user has a noisy version of the secret LUT. LUT-based methods have the limitation that the secrecy of the master key, under known-plaintext attack (KPA), relies on the difficulty in solving large linear system. In other words, with some knowledge of the plaintext, a dishonest user is able to derive the LUT, or an approximation of the LUT by solving a linear system. Resistance to such attack is crucial in the context of multimedia encryption since multimedia objects inherently contain high redundancies. Furthermore, for efficiency in decryption, the underlying linear system is likely to be sparse or not overly large, and hence can be solved using reasonable computing resource. In our experiment, a desktop PC is able to find a LUT (with 216 entries) within 2 hours. We propose a scheme that is resistant to KPA. The core of the scheme is a MUTABLE-PRNG (Pseudo Random Number Generator) whereby different but similar sequences are generated from related seeds. We generate such sequence from multiple pseudo random sequences based on majority-vote, and enhance its performance using error-correcting code. The proposed scheme is very simple and it is easy to show that it is resistant to KPA under reasonable cryptographic assumptions. However, it is not clear how much information on the original plaintext is leaked from the watermarked copies. We analyze the scheme and quantify the information loss using average conditional entropy.","PeriodicalId":124354,"journal":{"name":"ACM Digital Rights Management Workshop","volume":"187 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129509079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fingerprinting codes, originally designed for embedding traceable fingerprints in digital content, have many applications in cryptography; most notably, they are used to construct traitor tracing systems. Recently there has been some interest in constructing robust fingerprinting codes: codes capable of tracing words even when the pirate adversarially destroys a δ fraction of the marks in the fingerprint. An early construction due to Boneh and Naor produces codewords whose length is proportional to c4/(1-δ)2 where c is the number of words at the adversary's disposal. Recently Nuida developed a scheme with codewords of length proportional to (c log c)2/(1-δ) 2. In this paper we introduce a new technique for constructing codes whose length is proportional to (c log c)2/(1-δ), which is asymptotically optimal up to logarithmic factors. These new codes lead to traitor tracing systems with constant size ciphertext and asymptotically shorter secret keys than previously possible.
{"title":"Robust fingerprinting codes: a near optimal construction","authors":"D. Boneh, A. Kiayias, H. Montgomery","doi":"10.1145/1866870.1866873","DOIUrl":"https://doi.org/10.1145/1866870.1866873","url":null,"abstract":"Fingerprinting codes, originally designed for embedding traceable fingerprints in digital content, have many applications in cryptography; most notably, they are used to construct traitor tracing systems. Recently there has been some interest in constructing <i>robust</i> fingerprinting codes: codes capable of tracing words even when the pirate adversarially destroys a δ fraction of the marks in the fingerprint. An early construction due to Boneh and Naor produces codewords whose length is proportional to <i>c</i><sup>4</sup>/(1-δ)<sup>2</sup> where <i>c</i> is the number of words at the adversary's disposal. Recently Nuida developed a scheme with codewords of length proportional to (<i>c</i> log <i>c</i>)<sup>2</sup>/(1-δ) <sup>2</sup>. In this paper we introduce a new technique for constructing codes whose length is proportional to (<i>c</i> log <i>c</i>)<sup>2</sup>/(1-δ), which is asymptotically optimal up to logarithmic factors. These new codes lead to traitor tracing systems with constant size ciphertext and asymptotically shorter secret keys than previously possible.","PeriodicalId":124354,"journal":{"name":"ACM Digital Rights Management Workshop","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127789839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A proxy re-encryption (PRE) scheme involves three parties: Alice, Bob, and a proxy. PRE allows the proxy to translate a ciphertext encrypted under Alice's public key into one that can be decrypted by Bob's secret key. We present a general method to construct an identity-based proxy re-encryption scheme from an existing identity-based encryption scheme. The transformed scheme satisfies the properties of PRE, such as unidirectionality, non-interactivity and multi-use. Moreover, the proposed scheme has master key security, allows the encryptor to decide whether the ciphertext can be re-encrypted.
{"title":"New construction of identity-based proxy re-encryption","authors":"Song Luo, Jian-bin Hu, Zhong Chen","doi":"10.1145/1866870.1866880","DOIUrl":"https://doi.org/10.1145/1866870.1866880","url":null,"abstract":"A proxy re-encryption (PRE) scheme involves three parties: Alice, Bob, and a proxy. PRE allows the proxy to translate a ciphertext encrypted under Alice's public key into one that can be decrypted by Bob's secret key. We present a general method to construct an identity-based proxy re-encryption scheme from an existing identity-based encryption scheme. The transformed scheme satisfies the properties of PRE, such as unidirectionality, non-interactivity and multi-use. Moreover, the proposed scheme has master key security, allows the encryptor to decide whether the ciphertext can be re-encrypted.","PeriodicalId":124354,"journal":{"name":"ACM Digital Rights Management Workshop","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128041243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This document introduces the concept of an Interoperable Rights Locker which uses two elements: a digital rights locker that manages the consumer rights and a single interoperable format which enables portability. This concept is the most advanced model of DRM interoperability. The concept is illustrated by Disney's KeyChest system.
{"title":"An introduction to interoperable digital rights locker","authors":"E. Diehl, A. Robert","doi":"10.1145/1866870.1866881","DOIUrl":"https://doi.org/10.1145/1866870.1866881","url":null,"abstract":"This document introduces the concept of an Interoperable Rights Locker which uses two elements: a digital rights locker that manages the consumer rights and a single interoperable format which enables portability. This concept is the most advanced model of DRM interoperability. The concept is illustrated by Disney's KeyChest system.","PeriodicalId":124354,"journal":{"name":"ACM Digital Rights Management Workshop","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122012415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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