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28147-89




(FIPS PUB 81). 28147-89 , .

28147-89 :

;

;

;

.

ECB.

OFB, . .

, , . 3.10. 64- 0(1), 0(2),, 0(i),, 0(m), 0(i) i - 64- , i = 1m; m .

2 5 , 64 , ..

=((1), (2),, (i),, (m)),

(i) i - 64- , i = 1m.

0(m) 64, (m) .

(i) = 0(i) Å (i),

(i) = (Yi1 [+] C2, Zi1 [+]' C1), i=1m; (i) 1- 64- ; (×) ; [+] 232, [+]' 2321; 1, 2 32- ; Yi, Zi 32- .

Yi Zi : (Y0, Z0)=(Š), Š - (64- ), (Yi, Zi)=(Yi1 [+] C2, Zi1 [+] C1), i=1m.

. N6 N5 32- 1 2, ( ):

1 = 01010104(16), 2 = 01010101(16).

 

. 3.10. 28147-89.

 

256 ; N1 N2 64- () Š = (S1, S2,, S64).

Š N1 N2 m . N1 N2 . (Š)=(Y0 , Z0) 32- N3 N4 , N1 N3, N2 N4.

N4 (2321) 4 32- 1 N6. N4. N3 232 3 32- 2 N5. N3. N3 N1, N4 N2, N3, N4 . N1 N2 .

N1, N2 64- (1) = (g1(1), g2(1),, g63(1), g64(1)), 2 5 64- 0(1) = (t1(1), t2(1),, t63(1), t64(1)).

2 (1) 0(1) 64- :

(1) = (1) Å 0(1) = (t1(1), t2(1),, t63(1), t64(1)),

ti(1) = ti(1) Å gi(1), i=164.

64- (2) N4 (2321) 4 1 N6. N4. N3 232 3 2 N5. N3. N3 N1, N4 N2, N3 N4 . N1, N2 .

N1 N2 64- (2), 2 5 0(2): (2) = (2) Å 0(2).

(3), (4),, (m) 0(3), 0(4), 0(m).

Š (1), (2), (m).

, (. . 3.10). :

0(i) = (i) Å (i) = (i) Å (Yi1 [+] C2, Zi1 [+]' C1), i=1m.

, , .

. 256 , 0(1), 0(2), 0(m). N1 N2 , m (1), (2),, (m). (1), (2), (m). 2 5 (1), (2),, (m). 0(1), 0(2), 0(m). 0(m) 64 .

CFB.

, , , . 3.11.

, 64- 0(1), 0(2),, 0(m), 2 , 64 :

=((1), (2),, (i),, (m)).

0(m) 64, (m) .

:

(1) = (Š) Å 0(1) = (1) Å 0(1),

(i) = ((i-1)) Å 0(i) = (i) Å 0(i), i=2m.

(i) i - 64- ; (×) , m .

(×) 64- Š, (i1).

, 256 . N1 N2 Š = (S1, S2,, S64) 64 . N1 N2 . N1 N2 64- (1) = (Š), 2 5 64- 0(1) = (t1(1), t2(1),, t63(1), t64(1)). 64- (1) = (1) Å 0(1) = (t1(1), t2(1),, t63(1), t64(1)).

(1) N1, N2 (2), (1) N1 N2.

N1 N2 . N1 N2 64- (2), 2 5 0(2): (2) = (2) Å 0(2).

(i) 0(i) (i=3m) .

m - 0(m) 64 , (m) , .

 

. 3.11. 28147-89.

 

Š (1), (2),, (m).

, (. . 3.11). :

0(1) = (Š) Å (1) = (1) Å (1),

0(i) = ((i-1)) Å (i) = (i) Å (i), i=2m.

. 256 , 0(1), 0(2),, 0(m). N1 N2 Š. N1 N2 ( Š) . N1 N2
(1) = (Š), 2 5 (1). 0(1) = (1) Å (1).

(1) N1 N2 (2):
(2) = ((1)). N1 N2 . (2) 2 5 (2). . N1, N2 (2), (3),, (m), (3), (4),, (m).

2 5 (3), (4),, (m). 0(3), 0(4),, 0(m), 0(m) 64 .

CBC. 28147-89 , . , . , , (, , , ) .

( ) , 0,5.

64- 0(1), 0(2),, 0(m).

0(1) (×), 16 . 256 , .

16 64- (0(1)) 2 0(2).

((0(1)) Å 0(2)) (×). 64- ((0(1)) Å 0(2)) 2 0(3) (×), 64- ( ((0(1)) Å 0(2)) Å 0(3)), ..

0(m) ( 64- ) 2 (m1), , (×).

64- () : = [a(m)32P+1(16), a(m)32P+2(16),, a(m)32(16)], a(m)i i - 64- , 16- (×), 32P+1 £ i £ 32.

, .. (1), (2),, (m), .

(1), (2),, (m) , 0(1), 0(2),, 0(m) . , . 0(1), 0(2),, 0(m) .

1. .

2. .

3. 28147-89.

4. 28147-89.

5. / 28147-89.

6. Rijndael.

7. Rijndael.

8. Rijndael.

9. 3DES.

10. .

11. 28147-89.

12. , 28147-89.

, . , , 28147-89 (AES Advanced Encryption Standard). , , .





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