文章目录
- 总结
- Why we need hash functions
- Digital Signature with a Hash Function
- Basic Protocol for Digital Signatures with a Hash Function
- Principal input–output behavior of hash functions
- Security properties
- The three security requirements of hash functions
- Why the hash-based digital signature scheme is secure?
- Collision Resistance and the Birthday Attack
- Algorithms
- Constructing Hash Functions from Block Ciphers
- Dedicatd Hash Functions -- MD4 family of hash functions
- Example: The Secure Hash Algorithm SHA-256
- SHA-2
- SHA-256 Preprocessing
- The SHA-256 Compression Function
- Iteration j in the SHA-256 compression function
- 资料
总结

Why we need hash functions

Digital Signature with a Hash Function

Basic Protocol for Digital Signatures with a Hash Function

Principal input–output behavior of hash functions

Security properties
The three security requirements of hash functions


Why the hash-based digital signature scheme is secure?



Collision Resistance and the Birthday Attack





2的80次方是当前计算机可达到的
Algorithms


Constructing Hash Functions from Block Ciphers
每个xi是分组加密的输入长度,最终哈希结果是xn经过e函数的结果

这个反过来了,但最终哈希结果是xn经过e函数的结果


Dedicatd Hash Functions – MD4 family of hash functions



Example: The Secure Hash Algorithm SHA-256

SHA-2

总体框架

每块大小为 512 位


SHA-256 Preprocessing


The SHA-256 Compression Function




Iteration j in the SHA-256 compression function


资料
-
关于许多哈希函数及其规范的概览:
- http://ehash.iaik.tugraz.at/wiki/The_Hash_Function_Zoo
-
生日悖论(Birthday Paradox):
- Wikipedia 提供了一个很好的解释:
- http://en.wikipedia.org/wiki/Birthday_problem
-
SHA 标准:
- SHA1+2:
- http://csrc.nist.gov/publications/fips/fips180-2/fips180-2withchangenotice.pdf
- SHA3 概述:
- http://ehash.iaik.tugraz.at/wiki/The_SHA-3_Zoo
- SHA1+2:
-
CrypTool:
- CrypTool 是一个学习程序,同时也可以进行哈希操作:
- http://www.cryptool.org/



















