52 Things: Number 10: What is the difference between the RSA and strong-RSA problem?

52 Things: Number 10: What is the difference between the RSA and strong-RSA problem?

52件事:第10件:RSA和强RSA问题之间的区别是什么?

 
This is the latest in a series of blog posts to address the list of '52 Things Every PhD Student Should Know To Do Cryptography': a set of questions compiled to give PhD candidates a sense of what they should know by the end of their first year. This blog post introduces the RSA and Strong-RSA problems and highlights the differences between the two.
这是一系列博客文章中的最新一篇,旨在解决“每个博士生在做密码学时应该知道的52件事”:这是一组问题,旨在让博士生在第一年结束时了解他们应该知道什么。这篇博客文章介绍了RSA和强RSA问题,并强调了两者之间的区别。



Cryptography relies heavily on the assumption that certain mathematical problems are hard to solve in a realistic amount of time. When looking at Public-Key (Asymmetric) Cryptography, which is what we'll be focusing on in this blog post we use the assumed existence of One-Way functions, i.e. functions that are easy to compute one way but are difficult to invert. We use problems from algorithmic number theory to produce these functions.
密码学在很大程度上依赖于这样一种假设,即某些数学问题很难在现实的时间内解决。当我们在这篇博客文章中关注公钥(非对称)密码学时,我们使用了单向函数的假设存在,即易于单向计算但难以反转的函数。我们使用算法数论中的问题来产生这些函数。
 
Factoring 保付代理
 
The first difficult problem from number theory to talk about is factoring. Given a composite integer N the factoring problem is to find positive integers p,q such that N=pq. Although on the face of it this seems like a very simple problem, this is in fact a very tough, well studied problem. This can be solved in exponential time by checking all the numbers p=2,,N−−√. However, solving a problem in exponential time is not fast enough. No polynomial time algorithm has been developed to solve the factoring problem, despite many years of research. Clearly there are examples of N for which this is very easy to solve, for example whenever N is even. Therefore, when starting to think about using this in a Cryptographic construction we consider N as very large and being constructed by 2 large primes p,q
数论中要讨论的第一个难题是因子分解。给定一个复合整数 N ,因子分解问题是找到正整数 p,q ,使得#2。尽管从表面上看,这似乎是一个非常简单的问题,但事实上,这是一个十分棘手、研究充分的问题。这可以通过检查所有的数字#3在指数时间内解决。然而,在指数时间内解决问题是不够快的。尽管进行了多年的研究,但还没有开发出多项式时间算法来解决因子分解问题。很明显,有#4的例子很容易解决,例如,只要 N 是偶数。因此,当开始考虑在密码学构造中使用它时,我们认为 N 非常大,并且由2个大素数 p,q 构造。
 
The RSA Problem RSA问题

In RSA public-key encryption [1] Alice encrypts a plaintext M using Bob's public key (n,e) to ciphertext C by C=Me(mod n) where n is the product of two large primes and e3 is an odd integer that is coprime to the order of Zn, the group of invertible elements of Zn. Bob knows the private key (n,d) where de=1( mod (p1)(q1)) meaning he can compute M=Cd(mod n)An adversary can eavesdrop C and can know the public key (n,e) however to calculate M the adversary must find the factors of n. Therefore, this means the RSA problem is no harder than integer factorisation but is still a very hard problem to solve provided a suitable n is chosen. 
在RSA公钥加密[1]中,Alice使用Bob的公钥 (n,e) 将明文 M 加密为密文 C ,加密方式为 C=Me(mod n) ,其中#4是两个大素数的乘积, e3 是与 Zn 的可逆元素组 Zn 阶互质的奇整数。Bob知道私钥 (n,d) ,其中 de=1( mod (p1)(q1)) 意味着他可以计算 M=Cd(mod n) 。对手可以窃听 C 并且可以知道公钥 (n,e) ,但是为了计算 M ,对手必须找到 n 的因子。因此,这意味着RSA问题并不比整数分解更难,但如果选择了合适的 n ,它仍然是一个很难解决的问题。

The Strong RSA Assumption
RSA强假设


The strong RSA assumption differs from the RSA assumption in that the adversary can choose the (odd) public exponent e3. The adversary's task is to compute the plaintext M from the ciphertext given that C=Me(mod n). This is at least as easy as the RSA problem meaning that the strong RSA assumption is, unsurprisingly, a stronger assumption. The RSA problem is now over a quarter of a century old. Public key encryption schemes have been developed that derive their strength fully from the RSA problem.
强RSA假设与RSA假设的不同之处在于,对手可以选择(奇数)公共指数 e3 。对手的任务是从给定#2的密文中计算明文 M 。这至少和RSA问题一样容易,这意味着强RSA假设是一个更强的假设,这不足为奇。RSA问题已经存在了四分之一个多世纪。公钥加密方案已经被开发出来,其强度完全来自RSA问题。
posted @ 2024-04-11 12:50  3cH0_Nu1L  阅读(30)  评论(0编辑  收藏  举报