SHA (Secure Hash Algorithm) SHS (Secure Hash Standard) 1992 . SHA DSA.
SHA 160- , . SHA , , , , , . .
SHA. , 512 . : , , , 64 , 512, 64- .
32- :
= 067452301
B = 0xEFCDAB89
C = 0x98BADCFE
D = 0x10325476
E = 0xC3D2E1F0
. 512- , .
: A a, B b, C c, D d E e.
20 . a, b, c, d e, . SHA :
ft (X,Y,Z) = (X Ù Y) Ú ((Ø X) Ù Z), t = 0 19;
ft (X,Y,Z) = X Å Y Å Z, t = 20 39;
ft (X,Y,Z) = (X Ù Y) Ú(X Ù Z) Ú (Y Ù Z), t = 40 59;
ft (X,Y,Z) = X Å Y Å Z, t = 60 79.
:
Kt = 0x5A827999, t = 0 19;
Kt = 0x6ED9EBA1, t = 20 39;
Kt = 0x8FlBBCDC, t = 40 59;
Kt = 0xCA62C1D6, t = 60 79.
32- (M 0 M 15) 32- (W 0 W 79) :
Wt = Mt, t = 0 15;
Wt =(Wt 3 Å Wt 8 Å Wt 14 Å Wt 16) <<< 1, t = 16 79,
t ( t = 079), Wt t - , <<< S S .
- 80 (t = 079), :
TEMP = (a <<< 5) + ft (b, c, d)+ e + Wt + Kt
e = d
d = c
c = b <<< 30
b = a
a = TEMP
. 4.4 .
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. 4.4. SHA. |
a, b, c, d e A, B, C, D E, , 512- . A, B, C, D E.