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    Method and system for password protocols in the bounded retrieval model with security against dictionary attacks and intrusions
    4.
    发明申请
    Method and system for password protocols in the bounded retrieval model with security against dictionary attacks and intrusions 有权
    有限检索模型中密码协议的方法和系统，具有针对字典攻击和入侵的安全性

    公开(公告)号：US20070180260A1

    公开(公告)日：2007-08-02

    申请号：US11644368

    申请日：2006-12-22

    申请人： Giovanni Crescenzo ,  Richard Lipton ,  Sheldon Walfish

    发明人： Giovanni Crescenzo ,  Richard Lipton ,  Sheldon Walfish

    IPC分类号： H04L9/00

    CPC分类号： G06F21/31 ,  G06F21/46 ,  G06F21/62 ,  H04L63/1416

    摘要： Efficient secure password protocols are constructed that remain secure against offline dictionary attacks even when a large, but bounded, part of the storage of a server responsible for password verification is retrieved by an adversary through a remote or local connection. A registration algorithm and a verification algorithm accomplish the goal of defeating a dictionary attack. A password protocol where a server, on input of a login and a password, carefully selects several locations from the password files, properly combines their content according to some special function, and stores the result of this function as a tag that can be associated with this password and used in a verification phase to verify access by users. Two main instantiations of our method are given; in one, a combination of mathematical tools, called dispersers and pairwise-independent hash functions is used to achieve security against adaptive intrusions (dispersers make sure that the password of each user depends on randomly chosen locations in a large password file, and pairwise-independent hash functions help in making this dependency sufficiently random); in a second one, a combination of mathematical tools, called k-wise independent hash functions and locally-computable and strong extractors (k-wise independent hash functions make sure that the locations chosen in the large password file from each password are sufficiently random, and locally-computable and strong extractors are used to combine the contents of these locations to generate a single long random value, which makes verification harder for the adversary to foil).

    摘要翻译： 构建有效的安全密码协议，即使当负责密码验证的服务器的存储的大型但有限的部分通过远程或本地连接被对手检索时，仍然可以防止离线字典攻击。 注册算法和验证算法实现了击败字典攻击的目标。 密码协议，其中服务器输入登录名和密码，从密码文件中仔细选择多个位置，根据一些特殊功能正确组合其内容，并将此功能的结果存储为可与 此密码用于验证阶段，以验证用户的访问。 给出了我们的方法的两个主要实例; 在一个方面，使用称为分散器和成对独立散列函数的数学工具的组合来实现针对自适应入侵的安全性（分散器确保每个用户的密码取决于大密码文件中的随机选择的位置，并且成对独立 哈希函数有助于使此依赖性足够随机）; 在第二个方面，数学工具的组合，称为k-独立散列函数和本地可计算和强提取器（k-独立散列函数确保从每个密码在大密码文件中选择的位置是足够随机的， 并且使用本地可计算和强抽取器来组合这些位置的内容以产生单个长随机值，这使得对手更难验证。

    Method of using transient faults to verify the security of a cryptosystem
    6.
    发明授权
    Method of using transient faults to verify the security of a cryptosystem 失效
    使用瞬态故障验证密码系统的安全性的方法

    公开(公告)号：US06965673B1

    公开(公告)日：2005-11-15

    申请号：US09516910

    申请日：2000-03-01

    申请人： Dan Boneh ,  Richard Lipton ,  Richard A. DeMillo

    发明人： Dan Boneh ,  Richard Lipton ,  Richard A. DeMillo

    IPC分类号： G06F7/72 ,  H04K1/00 ,  H04L9/30 ,  H04L9/32

    CPC分类号： H04L9/3218 ,  G06F7/723 ,  G06F2207/7219 ,  H04L9/004 ,  H04L9/302 ,  H04L9/3249

    摘要： A useful method of verifying the integrity of a cryptosystem involves using erroneous outputs to obtain secret information. In certain signature schemes which use the Chinese Remainder Theorem, a correct signature of a message and an erroneous signature of the same message permit the modulus to be easily obtained. If the content of the message is known, such cryptosystems may be cracked with only an erroneous signature of the message. Certain other authorization schemes may be cracked by analyzing a number of erroneous outputs caused by a particular type of error called a “register fault.” A security expert or cryptosystem designer may intentionally induce a tamper proof device generate a faulty computation by subjecting the device, such as a smart card, to physical stress, such as certain types of radiation, atypical voltage levels, or a higher clock rate than the device was designed to accommodate. Cryptosystems should be impervious to the attacks described herein. If not, the system should be modified or discarded.

    摘要翻译： 验证密码系统的完整性的有用方法涉及使用错误的输出来获取秘密信息。 在使用中国剩余定理的某些签名方案中，消息的正确签名和相同消息的错误签名允许容易地获得模数。 如果消息的内容是已知的，则这样的密码系统可能仅以消息的错误签名被破解。 通过分析由称为“寄存器故障”的特定类型的错误导致的许多错误输出，某些其他授权方案可能会被破解。 安全专家或密码系统设计者可以有意地诱导防篡改设备通过使设备（例如智能卡）经受物理应力（例如某些类型的辐射，非典型电压电平或更高的时钟速率）来产生故障计算 设备被设计为容纳。 密码系统应该不受本文描述的攻击。 如果没有，系统应该被修改或者丢弃。