(FIPS PUB 81). 28147-89 , .
28147-89 :
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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 .
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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) .
:
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(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 .
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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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