:Ԗ2
: -1101
: ..
: ..
2013 .
1. . , : .
:
, 33 , :
Ũ
3. 3 . , :
ߨ |
2. 28147-89. 28147-89 . 64 8 : . (256 ) , 32 . 4 .
:
32 :
4 : .
(. ):
X0
, 64
L0: 11001010 11010011 11001101 11001000
R0: 11010110 11000000 00100000 11001110
32
0: 11000000 11001011 11001000 11001101
I. f(R0,X0) (. )
1). R0 X0 mod 232
R0: 1101 0110 1100 0000 0010 0000 1100 1110
0: 1100 0000 1100 1011 1100 1000 1100 1101
1000 1110 1000 1011 1110 1001 1001 0000
2).
R0+X0 mod 232
1000 1110 1000 1011 1110 1001 1001 0000
(. ). 4- . , . , 5- (1011) 11- (1110).
|
|
8 7 6 5 4 3 2 1
1000 1110 1000 1011 1110 1001 1001 0000
8 14 8 11 14 9 9 0
9 2 3 14 5 15 3 4
1001 0010 0011 1110 0101 1111 0011 0100
3). .2 11
1111 0010 1111 1001 1010 0100 1001 0001
, f (R0,X0):
1100 1101 0010 0100 1000 1111 1001 0111
II. R1= f(R0,X0) ÅL0.
f(R0,X0) L0 mod2:
L0: 1100 1010 1101 0011 1100 1101 1100 1000
f(R0,X0): 1111 0010 1111 1001 1010 0100 1001 0001
R1: 0011 1000 0010 1010 0110 1001 0101 1001
3. RSA. RSA, p q . , : .
I. (. ).
= 11 q = 29 (. ).
n = pq =11*29 = 319
j(n) = (p-1)(q-1) = 10*28 = 280.
d d < j(n) d j(n), .. d j(n) .
d = 3.
e e < j(n) de =1 (mod j(n)): e <280,
3 e =1(mod 280).
, 3 e -1 280 .
, e k,
3 e -1 = 280 k.
k =2 3 e =560+1
e =187.
(187, 319) ,
(3, 319) .
II. .
. ʻ 12, λ - 16 - 1.
, (187, 319):
1 = (12187) mod 319= 133
2 = (16187) mod 319=168
3 = (1187) mod 319= 1
, (12, 16, 1) (133, 168, 1).
III.
(133, 168, 1), (3,319):
1 = (1333) mod 319=12
2 = (1683) mod 319= 15
= (13) mod 319=1
(12, 16, 1), "".
4. . , , n = pq, p, q 3.
. p =11, q =29 (. ). n = pq =11*29=319. 9 ( ). (12, 21, 15, 10, 24, 1) . ,
n=280, H0=9, M1=12, M2=21, M3=15, M4=10, M5=24, M6=1.
,
- :
H1=(H0+M1)2 mod n = (8 + 12)2 mod 280 = 400 mod 319=81
H2=(H1+M2)2 mod n = (81 + 21)2 mod 280 = 104041 mod 319= 196
H3=(H2+M3)2 mod n = (196 + 15)2 mod 280 = 44521 mod 319= 180
H4=(H3+M4)2 mod n = (180 + 10)2 mod 280 = 36100 mod 319= 53
H5=(H4+M5)2 mod n = (53+ 24)2 mod 280 = 5929 mod 319= 187
H6=(H5+M6)2 mod n = (187 + 1)2 mod 280 = 35344 mod 319= 254
|
|
- , 254.
5. . - , RSA.
- 254, RSA (3, 319). , , (. )
s = 254 3 mod 319 = 34.
, (187, 319),
H = 34 187 mod 319 = 254.
- H, .