最近由于偶然原因,接触了CP-ABE(Ciphertext-Policy Attribute-Based Encryption),学了一段时间,觉得挺精妙,记录并分享一下学习心得。 什么是ABE(Attribute-Based Encryption)? 一言以蔽之:这是一种可以实现精准化访问控制功能的基于公钥密码的算法。 ABE 根据访问策略嵌入实体的不同可以分为两种: CP-ABE:将访问策略...
We develop a new cryptosystem for fine-grained sharing of encrypted data that we call Key-Policy Attribute-Based Encryption (KP-ABE). In our cryptosystem, cipher texts are labeled with sets of attributes and private keys are associated with access structures that control which cipher texts a ...
ABE，即基于属性加密，是实现精准化访问控制的公钥密码算法。ABE分为两类：KP-ABE适用于灵活性需求高，用户数量少的场景；CP-ABE则适用于用户数量多，追求高扩展性的场景。CP-ABE在加密文件时，根据访问策略设置属性，符合属性的用户仅需一次加密即可解密，如文件只能部门领导或组长访问，属性设为{role:...
The concept of attribute-based encryption (ABE) was first introduced by Sahai and Waters in 2005 (Sahai and Waters,2005). ABE was later categorized into two types (Goyal et al.,2006): ciphertext-policy ABE (CP-ABE) and key-policy ABE (KP-ABE). In CP-ABE, each ciphertext is associat...
1.1 Attribute-Based Encryption 基于属性加密机制 ABE机制是指将数据和数据用户属性相关联的一组规则,以提供对数据的访问控制。 1.2 Chameleon Hash Algorithm 变色龙哈希 人为设下一个“后门”(私钥)。掌握了它就能轻松找到碰撞,其中m不等于m′。假设一个区块原内容为m,有个人知道这个哈希的“后门”为x,这个“私钥...
To achieve fine grained and scalable data access control for medical records stored in semi trusted servers, we leverage attribute based encryption (ABE) techniques to encrypt each patients medical record file. In this paper, we describe a new approach which enables secure storage and controlled ...
As a new public key primitive, attribute-based encryption (ABE) is envisioned to be a promising tool for implementing fine-grained access control. To further address the concern of user access privacy, privacy-aware ABE schemes are being developed to achieve hidden access policy recently. For the...
Attribute-based encryption (ABE), as introduced by Sahai and Waters, allows for fine-grained access control on encrypted data. In its key-policy flavor (the dual ciphertext-policy scenario proceeds the other way around), the primitive enables senders to encrypt messages under a set of attribute...
Attribute-Based Encryption (ABE) offers fine-grained decryption policy such that users can do decryption if their attributes satisfy the policy. Such flexibility enables it applicable in various applications in government and business. However, there are two issues that should be solved first before ...
Attribute-based encryption (ABE) is a vision of public key encryption that allows users to encrypt and decrypt messages based on user attributes. This functionality comes at a cost. In a typical implementation, the size of the ciphertext is proportional to the number of attributes associated with...