People Who Live in Glass Houses Should not Throw Stones: Targeted Opening Message Franking Schemes
People Who Live in Glass Houses Should not Throw Stones: Targeted Opening Message Franking Schemes
复制标题
住在玻璃屋里的人不应该扔石头：有针对性的开幕信息邮资计划
DOI：
--
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Qiang Tang
中科院分区：
文献类型：
--
作者：
Long Chen;Qiang Tang
消息加盖印记使接收者能够报告采用端到端加密的安全消息传递系统中的潜在滥用。这种机制对问责至关重要，已经在Facebook Messenger等现实世界的产品中得到广泛采用。Grubs等人[5]开始了对这种新原语的系统研究，Dodis等人[2]给出了一个更有效的构造。我们观察到，在所有现有的报文加盖印花方案中，为了报告一次滥用，接收者必须透露会话的整个通信。这在许多情况下是非常不希望的，其中泄露通信的其他非滥用部分泄露了太多的信息；更糟糕的是，狡猾的对手可能故意将接收者的私人信息与滥用消息混合，使得接收者将不愿报告。这基本上使滥用报告机制无效。为了解决这一问题，我们提出了一种新的原语，称为目标开放紧凑提交AEAD(简称TOCE)。在ToCE中，接收方可以从明文中选择任意位的子集以在打开期间显示，同时保持所有其余部分的安全，就像在认证加密中一样。我们给出了一个仔细的公式，以及一个通用的结构，允许位水平有针对性的开放。虽然当加密诸如图片的大消息时，一般构造可能需要大量的对称密钥密码的通过，因此我们进一步阐述并给出了允许块级(例如，256位)打开的更有效的非黑盒构造。我们还提出了一种隐私效率的权衡，如果我们可以放松未打开的消息的安全性，使其在滥用报告后是单向安全的(如果没有打开，它们在语义上仍然是安全的)。
Message franking enables a receiver to report a potential abuse in a secure messaging system which employs an end to end encryption. Such mechanism is crucial for accountability and is already widely adopted in real world products such as the Facebook messenger. Grubs et al [5] initiated a systematic study of such a new primitive, and Dodis et al [2] gave a more efficient construction. We observe that in all existing message franking schemes, the receiver has to reveal the whole communication for a session in order to report one abuse. This is highly undesirable in many settings where revealing other non-abusive part of the communication leaks too much information; what is worse, a foxy adversary may intentionally mixing private information of the receiver with the abusive message so that the receiver will be reluctant to report. This essentially renders the abuse reporting mechanism ineffective. To tackle this problem, we propose a new primitive called targeted opening compactly committing AEAD (TOCE for short). In a TOCE, the receiver can select arbitrary subset of bits from the plaintext to reveal during opening, while keep all the rest still secure as in an authenticated encryption. We gave a careful formulation, together with a generic construction which allowing a bit level targeted opening. While the generic construction may require a substantial number of passes of symmetric key ciphers when encrypting a large message such as a picture, we thus further set forth and give a more efficient non-black-box construction allowing a block-level (e.g., 256 bit) opening. We also propose a privacyefficiency trade off if we can relax the security of non-opened messages to be one way secure after the abusive reporting (they are still semantically secure if no opening).
快速邮件邮资盖印：从隐形蝾螈到加密
DOI：
--
发表时间：
2018
期刊：
Advances in Cryptology - CRYPTO
影响因子：
--
作者：
Dodis, Yevgeniy;Grubbs, Paul;Ristenpart, Thomas;Woodage, Joanne
通讯作者：
Woodage, Joanne