Методы и средства защиты информации. Внимание!!! В книге могут встречаться существенные ошибки (в рисунках и формулах). Они не связаны ни со

Название	Внимание!!! В книге могут встречаться существенные ошибки (в рисунках и формулах). Они не связаны ни со
Анкор	Методы и средства защиты информации.pdf
Дата	17.08.2018
Размер	4.86 Mb.
Формат файла
Имя файла	Методы и средства защиты информации.pdf
Тип	Документы #23118
страница	54 из 63

1 ... 50 51 52 53 54 55 56 57 ... 63

Глава
18.
Криптографическая
защита
S1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
0 14 4 13 1
2 15 11 8
3 10 6 12 5
9 0
7 1
0 15 7
4 14 2 13 1 10 6 12 11 9
5 3
8 2
4 1 14 8 13 6
2 11 15 12 9
7 3 10 5
0 3 15 12 8
2 4
9 1
7 5 11 3 14 10 0
6 13
S2
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
0 15 1
8 14 6 11 3
4 9
7 2 13 12 0
5 10 1
3 13 4
7 15 2
8 14 12 0
1 10 6
9 11 5
2 0 14 7 11 10 4 13 1
5 8 12 6
9 3
2 15 3 13 8 10 1
3 15 4
2 11 6
7 12 0
5 14 9
S3
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
0 10 0
9 14 6
3 15 5
1 13 12 7 11 4
2 8
1 13 7
0 9
3 4
6 10 2
8 5 14 12 11 15 1
2 13 6
4 9
8 15 3
0 11 1
2 12 5 10 14 7
3 1 10 13 0
6 9
8 7
4 15 14 3 11 5
2 12
S4
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
0 7 13 14 3
0 6
9 10 1
2 8
5 11 12 4 15 1 13 8 11 5
6 15 0
3 4
7 2 12 1 10 14 9
2 10 6
9 0 12 11 7 13 15 1
3 14 5
2 8
4 3
3 15 0
6 10 1 13 8
9 4
5 11 12 7
2 14
S5
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
0 2 12 4
1 7 10 11 6
8 5
3 15 13 0 14 9
1 14 11 2 12 4
7 13 1
5 0 15 10 3
9 8
6 2
4 2
1 11 10 13 7
8 15 9 12 5
6 3
0 14 3 11 8 12 7
1 14 2 13 6 15 0
9 10 4
5 3
S6
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
0 12 1 10 15 9
2 6
8 0 13 3
4 14 7
5 11 1 10 15 4
2 7 12 9
5 6
1 13 14 0 11 3
8 2
9 14 15 5
2 8 12 3
7 0
4 10 1 13 11 6
3 4
3 2 12 9
5 15 10 11 14 1
7 6
0 8 13
Окончание
таблицы
18.7
S7
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15

Стандарт
шифрования
данных
DES
417
0 4 11 2 14 15 0
8 13 3 32 9
7 5 10 6
1 1 13 0 11 7
4 9
1 10 14 3
5 12 2 15 8
6 2
1 4 11 13 12 3
7 14 10 15 6
8 0
5 9
2 3
6 11 13 8
1 4 10 7
9 5
0 15 14 2
3 12
S8
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
0 13 2
8 4
6 15 11 1 10 9
3 14 5
0 12 7
1 1 15 13 8 10 3
7 4 12 5
6 11 0 14 9
2 2
7 11 4
1 9 12 14 2
0 6 10 13 15 3
5 8
3 2
1 14 7
4 10 8 13 15 12 9
0 3
5 6 11
Пример реализации алгоритма
DES представлен в
листингах
18.3 и
18.4
(
компилятор
— PowerBasic).
Листинг
18.3.
Пример реализации алгоритма
DES на языке
Basic для шифрования файлов
$CPU 80386
$FLOAT NPX
$OPTIMIZE SPEED
$LIB ALL-
$OPTION CNTLBREAK ON
DECLARE FUNCTION MYBIN$ (n%)
DECLARE FUNCTION desalg$ (a$)
DECLARE SUB f (i%, a%(), x%())
DECLARE SUB transpose (datax%(), T%(), n%)
DECLARE SUB mrotate (keyx%())
DECLARE SUB stob (a$, mbits%())
DECLARE SUB btos (mbits%(), a$)
DECLARE SUB letbe (target%(), source%(), LAST%)
DECLARE SUB init (x() AS INTEGER, n%)
DECLARE SUB sboxinit (b() AS INTEGER)
DECLARE SUB xtob (a$, mbits%())
DIM s(1 TO 8, 1 TO 64) AS shared INTEGER

418
Глава
18.
Криптографическая
защита
Продолжение
листинга
18.3
'
Инициализация
RESTORE InitialTrl
DIM InitialTr(1 TO 64) AS shared INTEGER init InitialTr(), 64
RESTORE FinalTrl
DIM FinalTr(1 TO 64) AS shared INTEGER init FinalTr(), 64
RESTORE swappyl
DIM swappy(1 TO 64) AS shared INTEGER init swappy(), 64
RESTORE KeyTr1l
DIM KeyTr1(1 TO 56) AS shared INTEGER init KeyTr1(), 56
RESTORE KeyTr2l
DIM KeyTr2(1 TO 48) AS shared INTEGER init KeyTr2(), 48
RESTORE etrl
DIM etr(1 TO 48) AS shared INTEGER init etr(), 48
RESTORE ptrl
DIM ptr(1 TO 32) AS shared INTEGER init ptr(), 32 sboxinit s()
RESTORE rotsl
DIM rots(1 TO 16) AS shared INTEGER init rots(), 16
DIM XR(1 TO 56) AS shared INTEGER
DIM EF(1 TO 64) AS shared INTEGER
DIM ikeyf(1 TO 64) AS shared INTEGER
DIM yf(1 TO 64) AS shared INTEGER

Стандарт_шифрования_данных__DES_419_Продолжение_листинга__18.3'>Стандарт
шифрования
данных
DES
419
Продолжение
листинга
18.3
DIM ades(1 TO 64) AS shared INTEGER
DIM bdes(1 TO 64) AS shared INTEGER
DIM xdes(1 TO 64) AS shared INTEGER
DIM XT(1 TO 64) AS shared INTEGER
DIM P2(1 TO 64) AS shared INTEGER
'
Главная программа main:
CLS parm$ = ltrim$(rtrim$(COMMAND$))+" "
IF LEN(parm$) > 1 THEN
Plainf$ = LTRIM$(RTRIM$(LEFT$(parm$, INSTR(parm$, " "))))
PRINT "
Исходный файл
: "; Plainf$
ELSE
INPUT "
Исходный файл
: ", plainf$
END IF if len(plainf$)=0 then print : print "
СБОЙ
: введите имя файла
!" system end if
OPEN plainf$ FOR RANDOM AS 1 lof1& = LOF(1)
IF lof1& = 0 THEN
CLOSE #1
KILL plainf$
PRINT : PRINT "
Файл не найден
!";
SYSTEM
ELSE
IF lof1& > 9999999 THEN PRINT : PRINT "
Исходный файл слишком велик
!": SYSTEM
CLOSE #1
OPEN plainf$ for binary access read as #1
END IF cipherf$ = "" sp0% = 0: sp% = 0
DO sp0% = sp% sp% = INSTR(sp% + 1, plainf$, "\")

420
Глава
18.
Криптографическая
защита
Продолжение
листинга
18.3
LOOP WHILE sp% > 0 bplainf$ = RIGHT$(plainf$, LEN(plainf$) - (sp0%))
PRINT "
Сохраняемое имя файла
: "; bplainf$ pp% = INSTR(sp0% + 1, plainf$, ".")
IF pp% = 0 THEN dcipherf$ = plainf$ + ".DES"
ELSE dcipherf$ = LEFT$(plainf$, pp% - 1) + ".DES"
END IF
PRINT "
По умолчанию
: "; dcipherf$
INPUT "
Выходной файл
: ", cipherf$
IF cipherf$ = "" THEN cipherf$ = dcipherf$
OPEN cipherf$ FOR RANDOM AS 2
IF LOF(2) > 0 THEN
CLOSE #2
PRINT : PRINT "
Выходной файл уже существует
!"
SYSTEM
ELSE
CLOSE #2
OPEN cipherf$ FOR binary AS 2
END IF
PW$ = ""
LOCATE 9, 1
INPUT ; "
Пароль
: ", PW$
IF (LEN(PW$) < 8) THEN PW$ = PW$ + STRING$(8 - LEN(PW$), 0)
IF len(pw$) = 16 then
LOCATE 9, 8: PRINT "
Пароль
: "; STRING$(16, 15); STRING$(10, " ")
PW$ = ucase$(PW$) xtob PW$, P2()
ELSE
LOCATE 9, 8: PRINT "
Пароль
: "; STRING$(8, 15); STRING$(10, " ")
PW$ = LEFT$(PW$, 8) stob PW$, P2() end IF

Стандарт_шифрования_данных__DES_423_Продолжение_листинга__18.3'>Стандарт
шифрования
данных
DES
421
Продолжение
листинга
18.3 transpose P2(), KeyTr1(), 56 ciphertekst$ = "" blocks& = lof1& \ 256 w = RND(-INT(TIMER)) anything$ = ""
FOR i% = 1 TO 12 anything$ = anything$ + CHR$(128 + INT(127 * RND(1)))
NEXT i% header$ = "#" + LTRIM$(STR$(lof1&)) header$ = "DES" + LEFT$(anything$, 8 - LEN(header$)) + header$ header$ = header$ + RIGHT$(anything$, 12 - LEN(bplainf$)) +
"#" + bplainf$ cheader$=desalg$(left$(header$,8))+desalg$(MID$(header$,9,8))+d esalg$(right$(header$,8)) put$ #2, cheader$
LOCATE 10, 8: PRINT ; "
Шифрование
: 0 %"; inblock$=space$(256)
FOR n& = 1 TO blocks& get$ #1,256,inblock$ outblock$="" for b%=1 to 256 step 8 outblock$ = outblock$+desalg$(mid$(inblock$,b%,8)) next
Put$ #2, outblock$
LOCATE 10, 19: PRINT ; USING "###"; (n& / blocks&) * 100;
NEXT n& rest1 = lof1& MOD 256 rest2 = lof1& MOD 8 rest = rest1-rest2
IF rest1 > 0 THEN outblock$="" get$ #1,rest1,inblock$

422
Глава
18.
Криптографическая
защита
Продолжение
листинга
18.3 if rest2 > 0 then inblock$=inblock$+left$(anything$,(8-rest2)) end if for b%=1 to len(inblock$) step 8 outblock$ = outblock$+desalg$(mid$(inblock$,b%,8)) next
Put$ #2, outblock$
END IF
CLOSE
LOCATE 10, 19: PRINT "100 % завершено "
PRINT : PRINT "
Шифрование по алгоритму
DES завершено
."
PRINT
SYSTEM
'
Данные и
функции
InitialTrl:
DATA 58,50,42,34,26,18,10,02,60,52,44,36,28,20,12,04
DATA 62,54,46,38,30,22,14,06,64,56,48,40,32,24,16,08
DATA 57,49,41,33,25,17,09,01,59,51,43,35,27,19,11,03
DATA 61,53,45,37,29,21,13,05,63,55,47,39,31,23,15,07
FinalTrl:
DATA 40,08,48,16,56,24,64,32,39,07,47,15,55,23,63,31
DATA 38,06,46,14,54,22,62,30,37,05,45,13,53,21,61,29
DATA 36,04,44,12,52,20,60,28,35,03,43,11,51,19,59,27
DATA 34,02,42,10,50,18,58,26,33,01,41,09,49,17,57,25 swappyl:
DATA 33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48
DATA 49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64
DATA 01,02,03,04,05,06,07,08,09,10,11,12,13,14,15,16
DATA 17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32
KeyTr1l:
DATA 57,49,41,33,25,17,09,01,58,50,42,34,26,18,10,02
DATA 59,51,43,35,27,19,11,03,60,52,44,36
DATA 63,55,47,39,31,23,15,07,62,54,46,38,30,22,14,06
DATA 61,53,45,37,29,21,13,05,28,20,12,04

Стандарт_шифрования_данных__DES_427_Продолжение_листинга__18.3'>Стандарт
шифрования
данных
DES
423
Продолжение
листинга
18.3
KeyTr2l:
DATA 14,17,11,24,01,05,03,28,15,06,21,10,23,19,12,04
DATA 26,08,16,07,27,20,13,02,41,52,31,37,47,55,30,40
DATA 51,45,33,48,44,49,39,56,34,53,46,42,50,36,29,32 etrl:
DATA 32,01,02,03,04,05,04,05,06,07,08,09,08,09,10,11
DATA 12,13,12,13,14,15,16,17,16,17,18,19,20,21,20,21
DATA 22,23,24,25,24,25,26,27,28,29,28,29,30,31,32,01 ptrl:
DATA 16,07,20,21,29,12,28,17,01,15,23,26,05,18,31,10
DATA 02,08,24,14,32,27,03,09,19,13,30,06,22,11,04,25 sboxesl:
DATA 14,04,13,01,02,15,11,08,03,10,06,12,05,09,00,07
DATA 00,15,07,04,14,02,13,01,10,06,12,11,09,05,03,08
DATA 04,01,14,08,13,06,02,11,15,12,09,07,03,10,05,00
DATA 15,12,08,02,04,09,01,07,05,11,03,14,10,00,06,13
DATA 15,01,08,14,06,11,03,04,09,07,02,13,12,00,05,10
DATA 03,13,04,07,15,02,08,14,12,00,01,10,06,09,11,05
DATA 00,14,07,11,10,04,13,01,05,08,12,06,09,03,02,15
DATA 13,08,10,01,03,15,04,02,11,06,07,12,00,05,14,09
DATA 10,00,09,14,06,03,15,05,01,13,12,07,11,04,02,08
DATA 13,07,00,09,03,04,06,10,02,08,05,14,12,11,15,01
DATA 13,06,04,09,08,15,03,00,11,01,02,12,05,10,14,07
DATA 01,10,13,00,06,09,08,07,04,15,14,03,11,05,02,12
DATA 07,13,14,03,00,06,09,10,01,02,08,05,11,12,04,15
DATA 13,08,11,05,06,15,00,03,04,07,02,12,01,10,14,09
DATA 10,06,09,00,12,11,07,13,15,01,03,14,05,02,08,04
DATA 03,15,00,06,10,01,13,08,09,04,05,11,12,07,02,14
DATA 02,12,04,01,07,10,11,06,08,05,03,15,13,00,14,09
DATA 14,11,02,12,04,07,13,01,05,00,15,10,03,09,08,06
DATA 04,02,01,11,10,13,07,08,15,09,12,05,06,03,00,14
DATA 11,08,12,07,01,14,02,13,06,15,00,09,10,04,05,03

424
Глава
18.
Криптографическая
защита
Продолжение
листинга
18.3
DATA 12,01,10,15,09,02,06,08,00,13,03,04,14,07,05,11
DATA 10,15,04,02,07,12,09,05,06,01,13,14,00,11,03,08
DATA 09,14,15,05,02,08,12,03,07,00,04,10,01,13,11,06
DATA 04,03,02,12,09,05,15,10,11,14,01,07,06,00,08,13
DATA 04,11,02,14,15,00,08,13,03,12,09,07,05,10,06,01
DATA 13,00,11,07,04,09,01,10,14,03,05,12,02,15,08,06
DATA 01,04,11,13,12,03,07,14,10,15,06,08,00,05,09,02
DATA 06,11,13,08,01,04,10,07,09,05,00,15,14,02,03,12
DATA 13,02,08,04,06,15,11,01,10,09,03,14,05,00,12,07
DATA 01,15,13,08,10,03,07,04,12,05,06,11,00,14,09,02
DATA 07,11,04,01,09,12,14,02,00,06,10,13,15,03,05,08
DATA 02,01,14,07,04,10,08,13,15,12,09,00,03,05,06,11 rotsl:
DATA 1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1
SUB btos (mbits() AS INTEGER, a$) a$ = ""
FOR i% = 1 TO 8 w% = 0
FOR j% = 1 TO 8 w% = w% + ((mbits(((i% - 1) * 8) + j%)) * (2 ^ (8 - j%)))
NEXT j% a$ = a$ + CHR$(w%)
NEXT i%
END SUB
FUNCTION desalg$ (a$) temp$ = "" stob a$, ades() transpose ades(), InitialTr(), 64
FOR i% = 1 TO 16 letbe bdes(), ades(), 64
FOR j% = 1 TO 32 ades(j%) = bdes(j% + 32)
NEXT j% f i%, ades(), xdes()
FOR j% = 1 TO 32 ades(j% + 32) = (bdes(j%) + xdes(j%)) MOD 2

Стандарт
шифрования
данных
DES
425
Продолжение
листинга
18.3
NEXT j%
NEXT i% transpose ades(), swappy(), 64 transpose ades(), FinalTr(), 64 btos ades(), temp$ desalg$ = temp$
END FUNCTION
SUB f (i%, a() AS INTEGER, x() AS INTEGER) h% = i%: letbe EF(), a(), 64 transpose EF(), etr(), 48
FOR j% = 1 TO rots(h%) mrotate P2()
NEXT j% letbe ikeyf(), P2(), 64: transpose ikeyf(), KeyTr2(), 48
FOR j% = 1 TO 48 yf(j%) = (EF(j%) + ikeyf(j%)) MOD 2
NEXT j%
FOR k% = 1 TO 8 k6% = 6 * k%: k4% = 4 * k% r% = (32 * yf(k6% - 5)) + (16 * yf(k6%)) + (8 * yf(k6% - 4)) +
(4 * yf(k6% - 3)) + (2 * yf(k6% - 2)) + yf(k6% - 1) + 1 x(k4% - 3) = (s(k%, r%) \ 8) MOD 2: x(k4% - 2) = (s(k%, r%) \
4) MOD 2 x(k4% - 1) = (s(k%, r%) \ 2) MOD 2: x(k4%) = s(k%, r%) MOD 2
NEXT k% transpose x(), ptr(), 32
END SUB
SUB init (x() AS INTEGER, n%)
FOR i% = 1 TO n%
READ x(i%)
NEXT i%
END SUB
SUB letbe (target() AS INTEGER, source() AS INTEGER, LAST%)
FOR i% = 1 TO LAST% target(i%) = source(i%)
NEXT i%
END SUB

426
Глава
18.
Криптографическая
защита
Продолжение
листинга
18.3
FUNCTION MYBIN$ (n%)
LOCAL ST$ p% = n%
ST$=""
FOR i% = 1 TO 8
IF (p% MOD 2) THEN
ST$ = "1" + ST$
ELSE
ST$ = "0" + ST$
END IF p% = p% \ 2
NEXT i%
MYBIN$ = ST$
END FUNCTION
SUB mrotate (keyr() AS INTEGER) letbe XR(), keyr(), 56
FOR i% = 1 TO 55
XR(i%) = XR(i% + 1)
NEXT i%
XR(28) = keyr(1): XR(56) = keyr(29) letbe keyr(), XR(), 56
END SUB
SUB sboxinit (b() AS INTEGER)
RESTORE sboxesl
FOR i% = 1 TO 8
FOR j% = 1 TO 64
READ b(i%, j%)
NEXT j%
NEXT i%
END SUB
SUB stob (a$, mbits() AS INTEGER)
FOR i% = 1 TO 8 b$ = MYBIN$(ASC(MID$(a$, i%, 1)))
FOR j% = 1 TO 8 mbits(((i% - 1) * 8) + j%) = ASC(MID$(b$, j%, 1)) - 48
NEXT j%
NEXT i%
END SUB

Стандарт
шифрования
данных
DES
427
Продолжение
листинга
18.3
SUB transpose (datax() AS INTEGER, T() AS INTEGER, n%) letbe XT(), datax(), 64
FOR i% = 1 TO n% datax(i%) = XT(T(i%))
NEXT i%
END SUB
SUB xtob (a$, mbits() AS INTEGER)
LOCAL X$,NIBBLE$
FOR i% = 1 to 16
X$ = MID$(a$,i%,1)
SELECT CASE X$
CASE "0"
NIBBLE$ = "0000"
CASE "1"
NIBBLE$ = "0001"
CASE "2"
NIBBLE$ = "0010"
CASE "3"
NIBBLE$ = "0011"
CASE "4"
NIBBLE$ = "0100"
CASE "5"
NIBBLE$ = "0101"
CASE "6"
NIBBLE$ = "0110"
CASE "7"
NIBBLE$ = "0111"
CASE "8"
NIBBLE$ = "1000"
CASE "9"
NIBBLE$ = "1001"
CASE "A"
NIBBLE$ = "1010"
CASE "B"
NIBBLE$ = "1011"
CASE "C"
NIBBLE$ = "1100"
CASE "D"
NIBBLE$ = "1101"
CASE "E"

428
Глава
18.
Криптографическая
защита
Окончание
листинга
18.3
NIBBLE$ = "1110"
CASE "F"
NIBBLE$ = "1111"
CASE ELSE
Print "
Не является
16- ричным значением
!"
SYSTEM
END SELECT
FOR j% = 1 to 4 mbits(((i% - 1) * 4) + j%) = ASC(MID$(NIBBLE$, j%, 1)) - 48
NEXT j%
NEXT i%
END SUB
Листинг
18.4.
Пример реализации алгоритма
DES на языке
Basic для расшифровывания файлов
$CPU 80386
$FLOAT NPX
$OPTIMIZE SPEED
$LIB ALL-
$OPTION CNTLBREAK ON
DECLARE FUNCTION MYBIN$ (n%)
DECLARE FUNCTION desalg$ (a$)
DECLARE SUB f (i%, a%(), x%())
DECLARE SUB transpose (datax%(), T%(), n%)
DECLARE SUB mrotate (keyx%())
DECLARE SUB stob (a$, mbits%())
DECLARE SUB btos (mbits%(), a$)
DECLARE SUB letbe (target%(), source%(), last%)
DECLARE SUB init (x() AS INTEGER, n%)
DECLARE SUB sboxinit (b() AS INTEGER)
DECLARE SUB xtob (a$, mbits%())
DIM s(1 TO 8, 1 TO 64) AS shared INTEGER
'
Инициализация
RESTORE InitialTrl

Стандарт
шифрования
данных
DES
429
Продолжение
листинга
18.4
DIM InitialTr(1 TO 64) AS shared INTEGER init InitialTr(), 64
RESTORE FinalTrl
DIM FinalTr(1 TO 64) AS shared INTEGER init FinalTr(), 64
RESTORE swappyl
DIM swappy(1 TO 64) AS shared INTEGER init swappy(), 64
RESTORE KeyTr1l
DIM KeyTr1(1 TO 56) AS shared INTEGER init KeyTr1(), 56
RESTORE KeyTr2l
DIM KeyTr2(1 TO 48) AS shared INTEGER init KeyTr2(), 48
RESTORE etrl
DIM etr(1 TO 48) AS shared INTEGER init etr(), 48
RESTORE ptrl
DIM ptr(1 TO 32) AS shared INTEGER init ptr(), 32 sboxinit s()
RESTORE rotsl
DIM rots(1 TO 16) AS shared INTEGER init rots(), 16
DIM XR(1 TO 56) AS shared INTEGER
DIM EF(1 TO 64) AS shared INTEGER
DIM ikeyf(1 TO 64) AS shared INTEGER
DIM yf(1 TO 64) AS shared INTEGER
DIM ades(1 TO 64) AS shared INTEGER
DIM bdes(1 TO 64) AS shared INTEGER

430

1 ... 50 51 52 53 54 55 56 57 ... 63