Difference between revisions of "SHA-1"

From The ECRYPT Hash Function Website
(State Update Transformation)
(State Update Transformation)
Line 9: Line 9:
 
==== State Update Transformation ====
 
==== State Update Transformation ====
 
<amsmath>
 
<amsmath>
 +
\begin{equation*}
 
\begin{aligned}
 
\begin{aligned}
     A_{i+1} &= A_i \lll 5 + W_i + f(B_i,C_i,D_i) + K_i\\
+
     A_{i+1} &= A_i \lr 5 + W_i + f(B_i,C_i,D_i) + K_i\\
 
     B_{i+1} &= A_i\\
 
     B_{i+1} &= A_i\\
     C_{i+1} &= B_i >> 2\\
+
     C_{i+1} &= B_i \rr \\
 
     D_{i+1} &= C_i\\
 
     D_{i+1} &= C_i\\
 
     E_{i+1} &= D_i
 
     E_{i+1} &= D_i
 
\end{aligned}
 
\end{aligned}
 +
\end{equation*}
 
</amsmath>
 
</amsmath>
  

Revision as of 09:37, 12 October 2006

1 General Description

SHA-1 is an iterated hash function.

1.1 Compression Function

The compression function takes as input a 512-bit message block and a 160-bit chaining variable, and produces a 160-bit chaining value. The compression function is described as follows:

1.1.1 Message Expansion

1.1.2 State Update Transformation

math

1.2 Padding Method

1.3 Initial Value and Constants

WikiTeX: latex reported a failure, namely:

/data/www/ehash/html/extensions/wikitex/wikitex.sh: line 59: latex: command not found

2 Claimed Security Margins

3 Security Anaylsis

  • Best know attack: <math>2^{63}</math> by Wang et.al.
  • Best known collision example: 64-step collision by De Canniere and Rechberger

something like: best know attack to date: kind of attack, which variant has been looked at (e.g. round-reduced), complexity, and reference to paper and abstract.

may be make here a new page with the other cryptanalysis results.