基本信息:
- 专利标题: MULTI-HOP PROXY RE-ENCRYPTION METHODS AND DEVICES
- 专利标题(中):多重代码重新加密方法和设备
- 申请号:PCT/EP2014/078872 申请日:2014-12-19
- 公开(公告)号:WO2015101533A1 公开(公告)日:2015-07-09
- 发明人: HEEN, Olivier , JOYE, Marc , LIBERT, Benoît
- 申请人: THOMSON LICENSING
- 申请人地址: 1-5 rue Jeanne d'Arc F-92130 Issy-les-Moulineaux FR
- 专利权人: THOMSON LICENSING
- 当前专利权人: THOMSON LICENSING
- 当前专利权人地址: 1-5 rue Jeanne d'Arc F-92130 Issy-les-Moulineaux FR
- 代理机构: STAHL, Niclas
- 优先权: EP14305004.5 20140103
- 主分类号: H04L9/08
- IPC分类号: H04L9/08 ; H04L9/30 ; H04L29/06
摘要:
The disclosure is directed to a proxy re-encryption scheme with limited delegations. To generate a formula (I) ciphertext for a message, wherein formula (II) is an integer, a (I) ciphertext enabling formula (IV) levels of re-encryption and L-1 is a maximum number of possible re-encryption levels, a processor (112) generates, in a (I) group of prime order p, a (I) encryption key for the (I) ciphertext from a public key and a (I) generator for the (I) group; obtains a first ciphertext component by multiplying the message with a generator of a final group formula (III) of a multi-linear configuration with L levels, the generator being raised to the power of an integer exponent; obtains a second ciphertext component by taking the (I) encryption key to the power of the integer exponent; and outputs the (I) ciphertext comprising the integer (II), the first ciphertext component and the second ciphertext component. In a preferred embodiment, the processor (112) includes an indicator of a time period in the (I) ciphertext; and, if the integer (IV), obtains a third ciphertext component by taking a hash value over the time period to the power of the integer exponent and includes the third ciphertext component in the (I) ciphertext that is output. Also provided are the re-encryption and decryption counterparts.
摘要(中):
本公开涉及具有有限授权的代理重新加密方案。 为了生成消息的公式(I)密文,其中公式(II)是整数,(I)密文使能公式(IV)再加密和L-1的级别是可能的重新加密级别的最大数量 处理器(112)以(I)素数阶组p生成来自公钥的(I)密文和(I)组的(I)生成器的(I)加密密钥; 通过将消息与具有L个级别的多线性配置的最终组公式(III)的生成器相乘来获得第一密文分量,生成器被提升为整数指数的幂; 通过将(I)加密密钥乘以整数指数的幂来获得第二密文分量; 并输出包含整数(II),第一密文分量和第二密文分量的(I)密文。 在优选实施例中,处理器(112)包括(I)密文中的时间段的指示符; 并且如果整数(IV)通过将该时间周期的散列值取为整数指数的幂来获得第三密文分量,并且包括输出的(I)密文中的第三密文分量。 还提供了重新加密和解密对手。