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PHÊ DUYỆT , GIAO NHIỆM VỤ ĐỀ TÀI
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Điểm:…………….( bằng chữ ………………………………………………).
Ngày ………tháng ………năm……….
Giảng viên hướng dẫn
TS.Đặng Hoài Bắc
LỜI CẢM ƠN
 !"#$
!%&'()*)+,)-. /012,34
54"
67 89: ;&)-%<=> 
?/@="
 67A . B 48@!CD%:2E@FA
G@;FHEI!A"FA&@()*7 %<=><
 J12K/0"
!A707*%,=LMNL!O%LMN$!:D%J
*&<=>,PKA.0Q"
F/R% 74(%&%A)>,
K, . 454"


MỤC LỤC
Đ?/@=8*:2
DANH MỤC CÁC KÝ HIỆU VÀ CHỮ KÝ VIẾT TẮT
!3  ,

!S GT4E@
S: S4 :4). !Q')*
S# S==4 #.,. UPV)W
FS F.X4S . 8,YVZ
L6# L446. #4)4.) UK[&\4)J@
L # L4 X#., !3/)Y,W
:USF :4  U4  S4 
F )
U&'Z71
]6!^ ].6.!4B^ . !_ V  9  .  ,Q  B`  '
].
]a ].a.    b4 V*
]a!E ].a.  !,  b4 V.Q(].
]a ]a.=.    b4 V4].
USF U4S4 F ) U&'Z7
ULc U4Lc b7'\4c
U]U6 U=.=   ].  U4
6 
Ud.K.4WH
e^F e5X .F  F[BYP4]6!^
e#S e,f#4.fS)4 b7'&\4B\4AB4
e#S
#gU]U6 #.g U=.=   ].
U46 
U]U677

#S #.S 4  B4
#La # L.= a.    b4 VA7=
#:SfD #.:4S .fD !' 177
#]a # ]4 a.    b4 VBd* =
#a]! #=4 ,.].!=  #=454 *.
!Fa !.4 F . a.    b4 VQBh.Q7
!# !.4 4.#. S=.Q)-
iSF i.SF G)RSF
Đ+$!jLMN$!:D Page 4
Đ?/@=8*:2
iS# i.S G)RS#.,.
iLa i.L44.4a.    b4 V)J @? C
)W
ie] iX .e .])4 . FkY)*V
ie iX .e . 4 . L*?KK
$U $U4.B=44 GAJ)0d.K
Đ+$!jLMN$!:D Page 5
Đ?/@=8*:2
DANH MỤC BẢNG
DANH MỤC CÁC HÌNH VẼ
Đ+$!jLMN$!:D Page 6
Đ?/@=8*:2
LỜI MỞ ĐẦU
!3J4/'=BlmM#]aK4 V'==
57 .4\4&=@.4.n#]a.0H=. 
*"#]a =o=Z@.QA) 4@=4=
@%\C)WhKWQV)W%Y,V.QA
h* .4JH1,B71"
G4%V)WFA@A&,4=_
.K.&&7d.0)@* P4/%B%&K"U2A

,@P4<4Q\hZ@34,Z_.P4,
H,*.p3,@2'=%4 )Y%q,@Cr"!07A
54JA,@Q) ,H57s,.Q.@
/*,0h7 '4"L \&2Qt(
h' ULc,V)W. 4 V#]au,K)v
FDv!_54,Q&ULc
Fwv!_54,Q4 V#]a
FOvx)WP4&ULc. 4 V#]a
:K%yDD1wMDw
#,Z
8+$!
Đ+$!jLMN$!:D Page 7
Đ?/@=8*:2
Đ+$!jLMN$!:D Page 8
Đ?/@=8*:2
Đ+$!jLMN$!:D Page 9
Đ?/@=8*:2FDv!_54,Q&ULc
CHƯƠNG 1: TỔNG QUAN VỀ MÃ MD5
1.1 Những khái niệm về mật mã hóa
U& K.(_A%C)W' nWH
BA B\hh,QB\4pBrh)Y
"
EZ=.h*zP4(%BAQ0].
Q7h=.h"8Q0z7,0Q,Q7 '%K
 \%*+'.4.n%AP4*4Y ){";*z.44 
*CKV K*P4(*YKB|*9 \
.K,C4_V KK)B%,4*J4\K
=?4.Y"e0\h(7%Q*4\.K7Z
@=P4*QzY)24ABA77 "8h,3477
AAB/%,3477 /7 'P4A(===/

0& A"G4,@& &.d=_'=%5/44
AQ\H=.hAW& .@h7 ,@
 HAP42"
U'&\4C)W=_h77 4  A*"F
KHv
 ;H'vFk\'&Z\h0.4K)P4A
V4Z. )*&'&\4P4\"G\B%\BAh
=o=0B}ABh ,QK)P4A@="
 G,~vG'\B71YA\Y4
_. 5.(.QA4BA"
 $ZvG'\B71YC,Bh.4
C\\ZZCA4BA"
Đ+$!jLMN$!:D Page 10
Đ?/@=8*:2FDv!_54,Q&ULc
1.2 Các thuật toán mã hóa
1.2.1 Mã hóa đối xứng
Hình 1.1 Nguyên lý của hệ thống mã hóa đối xứng.
Gs7P4@/& B /Vk.4. p(D"DrF\h
0.n70P4& /V7=H4,=H4=QC)WRK
B H'p#•r%,' d74=H4€Q/4"U& /V
.)Z4, ,@==/B K7 'J474=H4"GZB 
\*==/072. *%,,0Qtkênh bảo mậtu&
4J57.Y*"8Qh00V4B . 
5.(==/€\ 5Q.'=)J@) B \7 ,@"L \%5
.(==/B =7.tkênh bảo mậtu%0BhB 4B,'s
Đ+$!jLMN$!:D Page 11
Đ?/@=8*:2FDv!_54,Q&ULc
Hình 1.2 Kênh nguyên lý trong hệ thống mã hóa đối xứng.
1.2.2 Mã hóa bất đối xứng
G*,& /V%' 0/V *K H0

4B %4HK9=B "• C)W
khoá bí mật,khoá công khai,) \\B@mã hoá khoá công khai.U+
B C)Wh& 47&%B,' /V%.Y
P4B d+=H4B4"
!. @/e#S%)J@& nkhoá bí mật pKX
u
r,k\
h7&nB AB4P49=B \"F9=B * .4
R4,) \\54.Z=,4"U9)R\54@,4
4.'=B AB4(€BAhH 
.YP4B H'"L \%AB4B &€BA7dH
7 'P4@/%\€kKY4kHB H',-A
JBH";70P4& B AB4e#S0V7'&
Q\h'Z\& nB H'7&
nB AB4"!3\%=H4Y7?/P47";0
V JB AB4Q\h.K7'
U'&e#S%nZ@=o=Hh* .4K9=B\4
&4\Z@&\4,7&";. ,@HB\4(
4//\BH>P=R=,V)W"!4\7\5.(
'&e#S"
;C FAB4 ;'
Đ+$!jLMN$!:D Page 12
Đ?/@=8*:2FDv!_54,Q&ULc




F//v=%5
•="5
FB\4&)%/,

=fD%5fD
)"•Dp )Br
B•;#FGGp=fD%5fDr
8 *
•

p ) r
8&&\4

8&7&
•
)
p ) r
Hình 1.3 Mô tả tóm tắt quá trình mật mã RSA.
!H)Wv;'24//=•c‚5•ƒ"
!H•="5•Oc
!H=fD,5fDv =fD•„
5fD•y
B•;#FGGp„%yr•Dw
F29=&%)v F2DOO•")p ) Br•")p ) Dwr•D
!42•Dm‚)•ƒ
;C&\4,C '•

p ) r"!47C•w%
(4H•w
Dm
p ) Ocr•cw„wNN•wO"b.Y•wOC 
'"
;'7&7'v
•

)
 p ) Ocr"!4/4\&7•wO
ƒ
 p ) Ocr•
O„M„Nwc„„ƒ

p ) Ocr•w"
G,'B577&  H,B57&C"
Đ+$!jLMN$!:D Page 13
Đ?/@=8*:2FDv!_54,Q&ULc
1.3 Giới thiệu về hàm băm và mật mã
:1'&KPW0Y\, B/)J@0B},.7
,QK\K)/Y%2.Y1p'&r%0B}Z4_,A
(4s.)J@z4_.Y1"LJ@&\42
A@=p4r%,.Y1AB2\A@=
p4)r4.Y\p)r"
:1'&sd\„H0H4v
…LI)H.Y1,0B}A@= . %
…•Ah(KA@=3K.Y1 .%
…•AhC4KA@=BA4_.Y1P4\%
…•Ah(.4wA@=B4\R.Y1"
:1'&\.0QV)W. 4 A%0
JBs@CpL4#4.r%&'ZA@=pUSFjU4
S4 F )r%,K/)*'ZB"F<€\hC)W
1A%hk/)J@. 71vhk%
h')@)J@9=4Y@=)J@)0v4Bh
'Z4_)J@
1.3.1 Tính chất
:1'&B,, \K)Rs
,B57.4K.Y1\K)/Y":1'&=7\h

/*07Bh0A=H&"!/h%\=7\H
04v
•Q7pa.4.4rv .K.Y1%B\(.4
A@=4&•4pr"•@KQp †4
X r"FH0zY_d0AQ7
p=.444Br"
•Q7Vwp# )=.4.4rv .K, D%
B\\h(.4, wBpBAnDr4&4pDr•4pwr"
!H0ABB,4*p†4B  .4r"F
H0zY_d0AQ7Vwp )=.4
44Br"
•,4*pF  .4rvB\\h(.4wA@=D,w4
&4pDr•4pwr"UK9=,'2K,4*1p'&r%
,H0ABB,4**p.   .4r"!H
Đ+$!jLMN$!:D Page 14
Đ?/@=8*:2FDv!_54,Q&ULc
0.nK.Y1/h€*BQ7%
J4,4*\h(d0Ap.)444Br"
FH0.\.n/=sBAh4 9C4)J@
, BA4_.Y\P4\"L \%w\RK
.Y\%(4d.n</4"UK\
H,-\h\H0BA /":@*1'&
A,-Y_d0Ad.KK)pf 
44Brv .pr,prBA%n2‡=s%B|
0A\hHpˆˆ‡r%,ˆˆBs@=o=o="!H0\h
C)Wh=,>?Z7)Z4, 1"F0.<
:USFp:4U4S4 F )r9==7,0Q,'"
 EQ9sd%4\h/QB@*"•|0A
BAh(.4wA@=\.Y\/4‚ 9'.40
B}A\H ,Q)J@%k ..Y\"L \%1

'&=7-pV\hr,-0Y,H
 @57"
!' B%FeFOw,FeFpFe))4FBr
B%BQ%,\BA/
1'&"EH)W%\KFeF&C)WBh.4H ,~. [
&‰6ap‰.)65,4a.,4r%&\K0AB4H
HP4B"
1.3.2 Ứng dụng
UKV)WhP41'&z4vS9.4K
 B\ ; %,/.nA4&7"; z=7/ZZ
@%4).nSBA74"L \%S,.47P4
(%K.Y -%H.Y1P4\, ; 
.Y1\pJH'7,.Y r";n%B; (.4
7P4(,4\%S\hV.nA4\7
nK.Y  ; "p8K,H)W,QK?4B
7. Z%,4.P4S,; z.(H%,
H'zK(\)I)7* K \ r"
UKV)W54.2P414 H ,~P4A
@="$Y@\4_ &Z@/,A@=p 9K'=
r%,H)W%\hZ@n .Y\A@=&
H .%,4\%.Qp 9ZB@ \r"
UK.Y\A@=€\h=W,WK=@
')*K'='K/@/57s&?%4 ?b%
Đ+$!jLMN$!:D Page 15
Đ?/@=8*:2FDv!_54,Q&ULc
U..4,U   %C)W.Y4DP4Q)*K)B4
pK)'=%W%,,rh')*<K)0)
0"UKV)WB54,@Z'B["U'B[BA
.J)*,17.{%,s) h%4n)*.Y\
"8hZ)R%'B[*)@ C)W1,

,.Y1.J"8QAB2=o=&\4KQp f
†4.= r"8/,74s) 7 ',@0%' J
Bs/kY.nk.Y\P4A ŠBsŠ%VBA=7 
KA "F1€\hC)W. ,@* 7-
p=) .4) rF.Y1C)Wh')*'=.
*4|=.f f=."EH)W%. KB)wB%K.Y1UL„f
hB=,BH'=%0=PAhY,Y?'=
%7'=,'K)P4\"p!. H%B)wB
=.BC)WhhY'=.J. *L B
awa"rFBU4K,H)WB"F.Y1'=,'
1)41 91h\Q@"
1.4 Hàm băm dựa trên mã khối
F\K/===C)W' &B/h)ZK1
'  &%  W  h  \      o  K  Q  p f†4   =.   X r"
F===ZK *KP4&B/C)W =o=
&"!071&%4 ?UL„%ULc%#:SfD,#:Sfw
)Z3=/&B/%<B. WH%
,A=7?h7 7.n'BA "
UK' '&B/[S6#\hC)W4
J' '&B/RkQ=7.7,Q@1%
\h'B@/Z@1'&,V1'
&B&\4Q\hC)WK' &B/%Y*
dBH& 9=V=7=R=,\%‹*. K/
@/<|A"
1.5 Hàm băm mật mã
:1'& 2h_KA@=\K)0B}
K)&\K)/YpRK, ' 1r"L&
2A@=.<2p4)r4.Y1p4,4r%*)@
A@=4"LI)'0.n1BA=7K "
L \%,A@=0B}%?*A@=‡Œ4  pr•p‡r"<%

4\.nt\ZWK7.4u"UK124 p4tHY
Đ+$!jLMN$!:D Page 16
Đ?/@=8*:2FDv!_54,Q&ULc
WKurBBAhYpnH r9=A@=,‡
4&Œ‡,pr•p‡r"!.Z%' 1KQ%)
\%.0B\h)Z*A@=43A@=.<2":1<=
YH ,~)J@P4Av24_%)R.0%.
A@= .%,H)W_.YD%Q4_A@=.<2
V"!H0JH. ,@=%Bh.4JBs@C%
 *&V'A@=%=/-%* .4B\4 5.(&
\4q
:1Q7 QV)W&\4"F\Q' hZ
@1%. /\%===#:SfD,ULcC)WB
=_3'=DmmM4"
 :1UL„pU4L„r,ULcpU4Lcrv
…:1UL„b e e,QY, 1DmmM"E 1
Dmmw%=77ULcP4' .4"
…!A@=.<2\K)DwN"
…G1Dmmc%:4L .&k.4ZWK4H. 7
oP47'p9)R4'Z=,>7'r"G1wMM„%\
7$4 ‰4%L ^%$•44,:  Ž&A/B57
,Q,@=,>' UL„,ULcn===0AWK"
1.6 Cấu trúc hàm băm
:1'&Q\0.<7'4v
F .KA@=U\K)0B}"!R ' C
)W%<4\h_K/, A@=h'A
@=\K)K/P4Kn/ ."F4A@=3
B/\BHn4vUD%Uw%qU
b2:.*\BH%XtouZ@4 .K
B/)J@,.*@"•d:

M
nK, .Bd*  \:

•Xp:
fD
%Ur,•D%w%O%q%:

HA@=.<2P4A@=U4
"
1.7 Ghép hàm băm mật mã
bo=B57.43Q1* .4HB,4*/h
€/K*0P4' . B/"EH)W%##C)W
o=/ULc,#:SfDh77 4 V\z,-4 'HK
1Y=,>"
Đ+$!jLMN$!:D Page 17
Đ?/@=8*:2FDv!_54,Q&ULc
!%,1U.BfL4•.)%o=/k*
=/0%VBA*"• k.4.nwf,4*)-f,4*
)I)(.4wA@=\R.Y1ULc%(BAB\h(0
QA@=BB|0A/0.Y1ULc/4"!. /
A@=,R.Y1ULc%\B71\K,4*#:SfD"
GA,@Z@(,4*#:SfDp4 h/(
Br4V"'='_Bd^"
1.8 Hàm băm MD5
1.8.1 Giới thiệu
:1UL„pU4L„rb e,QY, 1DmmM"
E 14%=77ULcP4' .4"FR,
===#:S%4===\h/KCs.04
H==)W. Z/,A@=)"
!A@=4zd.K)&$\K)K/P4

cDw"UKD, 4)&%=)&?)M,/R
)&y„h)IK)P4A@="L&?)M, 4 
)&$\K)K/cDw"
1.8.2 Khái niệm
ULcpU4fL4 .crK1h&\4,.Y1
DwN"!3K[.].%ULc&J)W.K.7
. .(4*%,€)RhBh.4H
,~P4'="
ULcBde 4)e,, 1DmmDh4 1
.\%UL„p€) AB%.\J4ULwr"
1.8.3 Ứng dụng
U)c\wV)W54.2v
 ULcC)W.K.7. =Qh77 .n
'=7,QBAY"GC)W\h J4A/
Bh.4=QnULcA/,A/Bh.4=
Q7,QnULc":@QiC)WULchBh.4
\\==/%. B@Q‰) †C)W=
QP4&V4"
 ULc)Rh&\4'B["UWHP4,@&\4
_K_'B[K *&B%4  3 *
Đ+$!jLMN$!:D Page 18
Đ?/@=8*:2FDv!_54,Q&ULc
&\BAh .d*'B["F\T4,@7&
BAh 9=70KB &4,A'pPh7
4B.r"
1.8.4 Thuật giải
ULc_KA@=\Q)0B(KB/\BH
/YDwN"!A@=4, |B/cDw"!A@=
4, K@hQ)P4\|4 cDw";K@ *K
4v

f!.‘D, /A@="
f!=\ *’.  BQ)P4\K/P4cDw
KB 7y„"
fa*z0=dK/y„h)hQ)4
P4A@="!' HP4ULc *K.KKDwN"F4\
.4„3Ow%BH@S%;%F,L"F.Yn//Y"#4
\' H|= *K.B/cDw"U+B/|=/
=,KK"“”JKB/A@=4 ?„Z4%
2,pt. )ur"U+,*?Dy5.(Z4)Z4.K
Q^%=o=K ),=o= 4.q
 :()A7K5.(. K,"F\„KQ^\
hC)W"U+,C)WKB4"
Đ+$!jLMN$!:D Page 19
Đ?/@=8*:2FDv!_54,Q&ULc
Hinh 1.4 Quá trình trong một vòng MD5

:1ULcp2\A@=f4)r|
.7,QK_/'=W=?Ow/="
1.9 Mã MD5 (Message Digest)
e 4)e,

&=.4;1ULw% UL„pDmmMr,
ULcpDmmDr"L 
•
•

ZP44–;1%4<4z
o;1ULc%A—7P4UL„,;1

—C

).K.&•%BP41€
 .0Q1B
1.9.1 Mô tả
8 ,   J BA• cDwf%

— 4   Dy BA•   Owf" 8 .4 P4
' K'=P4„BA•Owfh* A—;1DwNf)
0"8%44V@BA•cDwf%,B//Rp1—,
˜cDwfrP4V@%<4KKD, A•P4% 4\
Mh

—K)pcDwr"•57V@, K+U
\ K )4• cDw%,(,—4\h4U.4G† .)OwfpG
† .)z4• Dyr"
; % 4 ( / P4 V @ , „ BA• Owf S% ;%F, L p



4rv
S•MMDwO„cyƒ
;•MNm4)X
F•MX)4mN
L•Mƒyc„OwDM"
G

4

2S%;%F%L+/p4,4.4r"
;
V@


4.4QBA•cDwf%+BA•cDwf*

—4
.4DyBA•Owf, A•,9=P4ULc"b7C41—4%%,)4 S%
;%F,LA•,•BA•cDwf–P4V@";/,9=. ULcQ
\0.</4"U+,Z@DyA™v—@,K
=P4O. „.Y4%%,)4\\KB•57•.YV„%
=\K,KBA• Owf,KnA•"#4\%\)Y.K

—
4A™,KB•57, K. „.Y4%%4)"•57A•R
K.Y

—4A—
. „.Y4%%4)"
Đ+$!jLMN$!:D Page 20
•/P4V@
ED Ew EO
A
B
C
D
:=
a
b
d
c
<<<S
U• 

Đ?/@=8*:2FDv!_54,Q&ULc
Hình 1.5 Sơ đồ vòng lặp chính của MD5
Đ+$!jLMN$!:D Page 21
Đ?/@=8*:2FDv!_54,Q&ULc
Hình 1.6 Sơ đồ 1 vòng lặp của MD5
F\/=%+C)W +,v
^p$%Ž%’r•p$∧Žr∨pp¬$r∧’r
bp$%Ž%’r•p$∧’r∨pp¬’r∧Žr
:p$%Ž%’r•$⊕Ž⊕’
]p$%Ž%’r•Ž⊕p$∨pš’rr
quy ước:
$∧Žao= SGL.J4$,Ž
$∨Žao= ›e.J4$,Ž
$⊕Žao= $›e.J4$,Ž
š$ao= G›!.P4$
$œŽao=Kp ) 
w
Ow
r
$˜˜˜FP4$)Yh 4,4.,Y.HpM•˜Owr
GJ

—B4  

VP4$%Ž,’A—
'=,BA

%,+P4B•57€K'=,4n4"
GU



Kh)IP4BA• V•p••Dyr,˜˜˜=o=)—.
P4%(,9=\hh)I

4v
^^p4%%%)%U

%%

r

—h)I4•œpp4œ^p%%)rœU


œ

r˜˜˜r
bbp4%%%)%U

%%

r
h)I
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1.9.2 Cách thực hiện
;/,py„rzZ@

4v
Vòng 1:
Đ+$!jLMN$!:D Page 22
Đ?/@=8*:2FDv!_54,Q&ULc

^^p4%%%)%UM%ƒ%Mƒy44„ƒNr
^^p)%4%%%UD%Dw%MNƒƒcyr
^^p%)%4%%Uw%Dƒ%Mw„wMƒM)r
^^p%%)%4%UO%ww%MD)r
^^p4%%%)%U„%ƒ%MXcƒMX4Xr
^^p)%4%%%Uc%Dw%M„ƒNƒyw4r
^^p%)%4%%Uy%Dƒ%M4NOM„yDOr
^^p%%)%4%Uƒ%ww%MX)„ymcMDr
^^p4%%%)%UN%ƒ%MymNMmN)Nr
^^p)%4%%%Um%Dw%MN„„Xƒ4Xr
^^p%)%4%%U
DM
%Dƒ%MXXXXcDr
^^p%%)%4%UDD%ww%MNmc)ƒr
^^p4%%%)%UDw%ƒ%MymMDDwwr
^^p)%4%%%UDO%Dw%MX)mNƒDmOr
^^p%)%4%%UD„%Dƒ%M4yƒm„ONr
^^p%%)%4%UDc%ww%M„m„MNwDr"
Vòng 2:
bbp4%%%)%UD%c%MyDwcywr
bbp)%4%%%Uy%m%MM„MO„Mr
bbp%)%4%%UDD%D„%Mwycc4cDr
bbp%%)%4%UM%wM%Mmyƒ44r
bbp4%%%)%Uc%c%M)ywXDMc)r
bbp)%4%%%UDM%m%MMw„„D„cOr
bbp%)%4%%UDc%D„%M)N4DyNDr
bbp%%)%4%U„%wM%Mƒ)OXNr
bbp4%%%)%Um%c%MwDD)yr
bbp)%4%%%UD„%m%MOOƒMƒ)yr
bbp%)%4%%UO%D„%MX„)cM)Nƒr

bbp%%)%4%UN%wM%M„cc4D„)r
bbp4%%%)%UDO%c%M4mOmMcr
bbp)%4%%%Uw%m%MXX4OXNr
bbp%)%4%%Uƒ%D„%MyƒyXMw)mr
bbp%%)%4%UDw%wM%MN)w4„N4r"
Đ+$!jLMN$!:D Page 23
Đ?/@=8*:2FDv!_54,Q&ULc
Vòng 3:
::p4%%%)%Uc%„%MXXX4Om„wr
::p)%4%%%UN%DD%MNƒƒDXyNDr
::p%)%4%%UDD%Dy%My)m)yDwwr
::p%%)%4%UD„%wO%MX)cONMr
::p4%%%)%UD%„%M4„4„„r
::p)%4%%%U„%DD%M„)X4mr
::p%)%4%%Uƒ%Dy%MXy„yMr
::p%%)%4%UDM%wO%MXƒMr
::p4%%%)%UDO%„%MwNmƒyr
::p)%4%%%UM%DD%M44DwƒX4r
::p%)%4%%UO%Dy%M)„XOMNcr
::p%%)%4%Uy%wO%MM„NND)Mcr
::p4%%%)%Um%„%M)m)„)MOmr
::p)%4%%%UDw%DD%My)mmcr
::p%)%4%%UDc%Dy%MDX4wƒXNr
::p%%)%4%Uw%wO%M„4cyycr"
Vòng 4:
]]p4%%%)%UM%y%MX„wmww„„r
]]p)%4%%%Uƒ%DM%M„Ow4XXmƒr
]]p%)%4%%UD„%Dc%M4m„wO4ƒr
]]p%%)%4%Uc%wD%MXmO4MOmr
]]p4%%%)%UDw%y%MycccmOr

]]p)%4%%%UO%DM%MNXMmwr
]]p%)%4%%UDM%Dc%MXXXX„ƒ)r
]]p%%)%4%UD%wD%MNcN„c))Dr
]]p4%%%)%UN%y%MyX4Nƒ„Xr
]]p)%4%%%UDc%DM%MXwyMr
]]p%)%4%%Uy%Dc%M4OMDO„D„r
]]p%%)%4%UDO%wD%M„MNDD4Dr
]]p4%%%)%U„%y%MXƒcOƒNwr
]]p)%4%%%UDD%DM%M)O4XwOcr
]]p%)%4%%Uw%Dc%Mw4)ƒ)wr
]]p%%)%4%Um%wD%MNy)OmDr"
GJn/



—2 5'4vd

V.Y


=–
Đ+$!jLMN$!:D Page 24
Đ?/@=8*:2FDv!_54,Q&ULc
P4w
Ow
ž4pprr%. \•ŸM""yO 

—
•
 .4)4"

#407J4%%,)

—

—K,S%;%F,Lh
 B•57–.4,' 4•=W,•BA•)J@cDwf=  •
• V@"8.4A•RKBA•DwNfP4S%;%F,L%
•

;1'

—"
Hình 1.7 Một ví dụ về mã MD5
Đ+$!jLMN$!:D Page 25

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