Kerberos是广泛应用于云计算、物联网等场景下的身份认证系统,其密钥分发中心(key distribution center,KDC)的数据库存储着明文的密钥信息,在分布式环境中存在存储管理、内存泄露等安全隐患,进而影响身份认证系统的安全.因此提出基于In...Kerberos是广泛应用于云计算、物联网等场景下的身份认证系统,其密钥分发中心(key distribution center,KDC)的数据库存储着明文的密钥信息,在分布式环境中存在存储管理、内存泄露等安全隐患,进而影响身份认证系统的安全.因此提出基于Intel SGX(software guard extensions)的Kerberos安全增强方案,将密钥的初始化和身份认证流程中涉及密钥使用模块迁移至SGX提供的安全隔离区域Enclave中,通过基于硬件支持的内存隔离机制动态保护密钥;在安全区内使用密封机制密封存储至数据库.通过实验证明了该方案能够保障密钥动态和静态的机密性和完整性,减小了可信计算基础的范围.而性能评估显示,该方案在保障密钥运行和存储安全的同时,性能的额外开销也在可接受范围之内.展开更多
Due to limited computing and storage resources,light clients and full nodes coexist in a typical blockchain system.Any query from light clients must be forwarded to full nodes for execution,and light clients verify th...Due to limited computing and storage resources,light clients and full nodes coexist in a typical blockchain system.Any query from light clients must be forwarded to full nodes for execution,and light clients verify the integrity of query results returned.Since existing verifiable queries based on an authenticated data structure(ADS)suffer from significant network,storage and computing overheads by virtue of verification objects(VOs),an alternative way turns to the trusted execution environment(TEE),with which light clients do not need to receive or verify any VO.However,state-of-the-art TEEs cannot deal with large-scale applications conveniently due to the limited secure memory space(e.g.,the size of the enclave in Intel SGX(software guard extensions),a typical TEE product,is only 128 MB).Hence,we organize data hierarchically in trusted(enclave)and untrusted memory,along with hot data buffered in the enclave to reduce page swapping overhead between two kinds of memory.The cost analysis and empirical study validate the effectiveness of our proposed scheme.The VO size of our scheme is reduced by one to two orders of magnitude compared with that of the traditional scheme.展开更多
This paper presents a comprehensive survey on the development of Intel SGX(software guard extensions)processors and its applications.With the advent of SGX in 2013 and its subsequent development,the corresponding rese...This paper presents a comprehensive survey on the development of Intel SGX(software guard extensions)processors and its applications.With the advent of SGX in 2013 and its subsequent development,the corresponding research works are also increasing rapidly.In order to get a more comprehensive literature review related to SGX,we have made a systematic analysis of the related papers in this area.We first search through five large-scale paper retrieval libraries by keywords(i.e.,ACM Digital Library,IEEE/IET Electronic Library,SpringerLink,Web of Science,and Elsevier Science Direct).We read and analyze a total of 128 SGX-related papers.The first round of extensive study is conducted to classify them.The second round of intensive study is carried out to complete a comprehensive analysis of the paper from various aspects.We start with the working environment of SGX and make a conclusive summary of trusted execution environment(TEE).We then focus on the applications of SGX.We also review and study multifarious attack methods to SGX framework and some recent security improvements made on SGX.Finally,we summarize the advantages and disadvantages of SGX with some future research opportunities.We hope this review could help the existing and future research works on SGX and its application for both developers and users.展开更多
In modern computer systems,user processes are isolated from each other by the operating system and the hardware.Additionally,in a cloud scenario it is crucial that the hypervisor isolates tenants from other tenants th...In modern computer systems,user processes are isolated from each other by the operating system and the hardware.Additionally,in a cloud scenario it is crucial that the hypervisor isolates tenants from other tenants that are co-located on the same physical machine.However,the hypervisor does not protect tenants against the cloud provider and thus,the supplied operating system and hardware.Intel SGX provides a mechanism that addresses this scenario.It aims at protecting user-level software from attacks from other processes,the operating system,and even physical attackers.In this paper,we demonstrate fine-grained software-based side-channel attacks from a malicious SGX enclave targeting co-located enclaves.Our attack is the first malware running on real SGX hardware,abusing SGX protection features to conceal itself.Furthermore,we demonstrate our attack both in a native environment and across multiple Docker containers.We perform a Prime+Probe cache side-channel attack on a co-located SGX enclave running an up-to-date RSA implementation that uses a constant-time multiplication primitive.The attack works,although in SGX enclaves,there are no timers,no large pages,no physical addresses,and no shared memory.In a semi-synchronous attack,we extract 96%of an RSA private key from a single trace.We extract the full RSA private key in an automated attack from 11 traces within 5 min.展开更多
In modern computer systems,user processes are isolated from each other by the operating system and the hardware.Additionally,in a cloud scenario it is crucial that the hypervisor isolates tenants from other tenants th...In modern computer systems,user processes are isolated from each other by the operating system and the hardware.Additionally,in a cloud scenario it is crucial that the hypervisor isolates tenants from other tenants that are co-located on the same physical machine.However,the hypervisor does not protect tenants against the cloud provider and thus,the supplied operating system and hardware.Intel SGX provides a mechanism that addresses this scenario.It aims at protecting user-level software from attacks from other processes,the operating system,and even physical attackers.In this paper,we demonstrate fine-grained software-based side-channel attacks from a malicious SGX enclave targeting co-located enclaves.Our attack is the first malware running on real SGX hardware,abusing SGX protection features to conceal itself.Furthermore,we demonstrate our attack both in a native environment and across multiple Docker containers.We perform a Prime+Probe cache side-channel attack on a co-located SGX enclave running an up-to-date RSA implementation that uses a constant-time multiplication primitive.The attack works,although in SGX enclaves,there are no timers,no large pages,no physical addresses,and no shared memory.In a semi-synchronous attack,we extract 96% of an RSA private key from a single trace.We extract the full RSA private key in an automated attack from 11 traces within 5 min.展开更多
基金supported by the National Key Research and Development Program of China under Grant No.2021YFB-2700100the National Natural Science Foundation of China under Grant Nos.U1911203,U1811264 and 61972152.
文摘Due to limited computing and storage resources,light clients and full nodes coexist in a typical blockchain system.Any query from light clients must be forwarded to full nodes for execution,and light clients verify the integrity of query results returned.Since existing verifiable queries based on an authenticated data structure(ADS)suffer from significant network,storage and computing overheads by virtue of verification objects(VOs),an alternative way turns to the trusted execution environment(TEE),with which light clients do not need to receive or verify any VO.However,state-of-the-art TEEs cannot deal with large-scale applications conveniently due to the limited secure memory space(e.g.,the size of the enclave in Intel SGX(software guard extensions),a typical TEE product,is only 128 MB).Hence,we organize data hierarchically in trusted(enclave)and untrusted memory,along with hot data buffered in the enclave to reduce page swapping overhead between two kinds of memory.The cost analysis and empirical study validate the effectiveness of our proposed scheme.The VO size of our scheme is reduced by one to two orders of magnitude compared with that of the traditional scheme.
基金supported by Fund of Shaanxi Science and Technology Research and Development Plan Project(2015GY073)Shaanxi Key Research and Development Program(2019GY-057).
文摘This paper presents a comprehensive survey on the development of Intel SGX(software guard extensions)processors and its applications.With the advent of SGX in 2013 and its subsequent development,the corresponding research works are also increasing rapidly.In order to get a more comprehensive literature review related to SGX,we have made a systematic analysis of the related papers in this area.We first search through five large-scale paper retrieval libraries by keywords(i.e.,ACM Digital Library,IEEE/IET Electronic Library,SpringerLink,Web of Science,and Elsevier Science Direct).We read and analyze a total of 128 SGX-related papers.The first round of extensive study is conducted to classify them.The second round of intensive study is carried out to complete a comprehensive analysis of the paper from various aspects.We start with the working environment of SGX and make a conclusive summary of trusted execution environment(TEE).We then focus on the applications of SGX.We also review and study multifarious attack methods to SGX framework and some recent security improvements made on SGX.Finally,we summarize the advantages and disadvantages of SGX with some future research opportunities.We hope this review could help the existing and future research works on SGX and its application for both developers and users.
基金This project has received funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation programme(grant agreement No 681402)This work was partially supported by the TU Graz LEAD project“Dependable Internet of Things in Adverse Environments”.
文摘In modern computer systems,user processes are isolated from each other by the operating system and the hardware.Additionally,in a cloud scenario it is crucial that the hypervisor isolates tenants from other tenants that are co-located on the same physical machine.However,the hypervisor does not protect tenants against the cloud provider and thus,the supplied operating system and hardware.Intel SGX provides a mechanism that addresses this scenario.It aims at protecting user-level software from attacks from other processes,the operating system,and even physical attackers.In this paper,we demonstrate fine-grained software-based side-channel attacks from a malicious SGX enclave targeting co-located enclaves.Our attack is the first malware running on real SGX hardware,abusing SGX protection features to conceal itself.Furthermore,we demonstrate our attack both in a native environment and across multiple Docker containers.We perform a Prime+Probe cache side-channel attack on a co-located SGX enclave running an up-to-date RSA implementation that uses a constant-time multiplication primitive.The attack works,although in SGX enclaves,there are no timers,no large pages,no physical addresses,and no shared memory.In a semi-synchronous attack,we extract 96%of an RSA private key from a single trace.We extract the full RSA private key in an automated attack from 11 traces within 5 min.
基金received funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation programme(grant agreement No 681402)partially supported by the TU Graz LEAD project“Dependable Internet of Things in Adverse Environments”.
文摘In modern computer systems,user processes are isolated from each other by the operating system and the hardware.Additionally,in a cloud scenario it is crucial that the hypervisor isolates tenants from other tenants that are co-located on the same physical machine.However,the hypervisor does not protect tenants against the cloud provider and thus,the supplied operating system and hardware.Intel SGX provides a mechanism that addresses this scenario.It aims at protecting user-level software from attacks from other processes,the operating system,and even physical attackers.In this paper,we demonstrate fine-grained software-based side-channel attacks from a malicious SGX enclave targeting co-located enclaves.Our attack is the first malware running on real SGX hardware,abusing SGX protection features to conceal itself.Furthermore,we demonstrate our attack both in a native environment and across multiple Docker containers.We perform a Prime+Probe cache side-channel attack on a co-located SGX enclave running an up-to-date RSA implementation that uses a constant-time multiplication primitive.The attack works,although in SGX enclaves,there are no timers,no large pages,no physical addresses,and no shared memory.In a semi-synchronous attack,we extract 96% of an RSA private key from a single trace.We extract the full RSA private key in an automated attack from 11 traces within 5 min.
