|
1 | 1 | from __future__ import print_function
|
2 | 2 | import math
|
3 | 3 |
|
| 4 | + |
4 | 5 | def rearrange(bitString32):
|
5 |
| - """[summary] |
6 |
| - Regroups the given binary string. |
7 |
| - |
8 |
| - Arguments: |
9 |
| - bitString32 {[string]} -- [32 bit binary] |
10 |
| - |
11 |
| - Raises: |
12 |
| - ValueError -- [if the given string not are 32 bit binary string] |
13 |
| - |
14 |
| - Returns: |
15 |
| - [string] -- [32 bit binary string] |
16 |
| - """ |
17 |
| - |
18 |
| - if len(bitString32) != 32: |
19 |
| - raise ValueError("Need length 32") |
20 |
| - newString = "" |
21 |
| - for i in [3,2,1,0]: |
22 |
| - newString += bitString32[8*i:8*i+8] |
23 |
| - return newString |
| 6 | + """[summary] |
| 7 | + Regroups the given binary string. |
| 8 | +
|
| 9 | + Arguments: |
| 10 | + bitString32 {[string]} -- [32 bit binary] |
| 11 | +
|
| 12 | + Raises: |
| 13 | + ValueError -- [if the given string not are 32 bit binary string] |
| 14 | +
|
| 15 | + Returns: |
| 16 | + [string] -- [32 bit binary string] |
| 17 | + >>> rearrange('1234567890abcdfghijklmnopqrstuvw') |
| 18 | + 'pqrstuvwhijklmno90abcdfg12345678' |
| 19 | + """ |
| 20 | + |
| 21 | + if len(bitString32) != 32: |
| 22 | + raise ValueError("Need length 32") |
| 23 | + newString = "" |
| 24 | + for i in [3, 2,1,0]: |
| 25 | + newString += bitString32[8*i:8*i+8] |
| 26 | + return newString |
| 27 | + |
24 | 28 |
|
25 | 29 | def reformatHex(i):
|
26 |
| - """[summary] |
27 |
| - Converts the given integer into 8-digit hex number. |
| 30 | + """[summary] |
| 31 | + Converts the given integer into 8-digit hex number. |
28 | 32 |
|
29 |
| - Arguments: |
30 |
| - i {[int]} -- [integer] |
31 |
| - """ |
| 33 | + Arguments: |
| 34 | + i {[int]} -- [integer] |
| 35 | + >>> reformatHex(666) |
| 36 | + '9a020000' |
| 37 | + """ |
| 38 | + |
| 39 | + hexrep = format(i, '08x') |
| 40 | + thing = "" |
| 41 | + for i in [3, 2,1,0]: |
| 42 | + thing += hexrep[2*i:2*i+2] |
| 43 | + return thing |
32 | 44 |
|
33 |
| - hexrep = format(i,'08x') |
34 |
| - thing = "" |
35 |
| - for i in [3,2,1,0]: |
36 |
| - thing += hexrep[2*i:2*i+2] |
37 |
| - return thing |
38 | 45 |
|
39 | 46 | def pad(bitString):
|
40 |
| - """[summary] |
41 |
| - Fills up the binary string to a 512 bit binary string |
42 |
| -
|
43 |
| - Arguments: |
44 |
| - bitString {[string]} -- [binary string] |
45 |
| - |
46 |
| - Returns: |
47 |
| - [string] -- [binary string] |
48 |
| - """ |
49 |
| - |
50 |
| - startLength = len(bitString) |
51 |
| - bitString += '1' |
52 |
| - while len(bitString) % 512 != 448: |
53 |
| - bitString += '0' |
54 |
| - lastPart = format(startLength,'064b') |
55 |
| - bitString += rearrange(lastPart[32:]) + rearrange(lastPart[:32]) |
56 |
| - return bitString |
| 47 | + """[summary] |
| 48 | + Fills up the binary string to a 512 bit binary string |
| 49 | +
|
| 50 | + Arguments: |
| 51 | + bitString {[string]} -- [binary string] |
| 52 | +
|
| 53 | + Returns: |
| 54 | + [string] -- [binary string] |
| 55 | + """ |
| 56 | + startLength = len(bitString) |
| 57 | + bitString += '1' |
| 58 | + while len(bitString) % 512 != 448: |
| 59 | + bitString += '0' |
| 60 | + lastPart = format(startLength, '064b') |
| 61 | + bitString += rearrange(lastPart[32:]) + rearrange(lastPart[:32]) |
| 62 | + return bitString |
| 63 | + |
57 | 64 |
|
58 | 65 | def getBlock(bitString):
|
59 |
| - """[summary] |
60 |
| - Iterator: |
61 |
| - Returns by each call a list of length 16 with the 32 bit |
62 |
| - integer blocks. |
63 |
| -
|
64 |
| - Arguments: |
65 |
| - bitString {[string]} -- [binary string >= 512] |
66 |
| - """ |
67 |
| - |
68 |
| - currPos = 0 |
69 |
| - while currPos < len(bitString): |
70 |
| - currPart = bitString[currPos:currPos+512] |
71 |
| - mySplits = [] |
72 |
| - for i in range(16): |
73 |
| - mySplits.append(int(rearrange(currPart[32*i:32*i+32]),2)) |
74 |
| - yield mySplits |
75 |
| - currPos += 512 |
| 66 | + """[summary] |
| 67 | + Iterator: |
| 68 | + Returns by each call a list of length 16 with the 32 bit |
| 69 | + integer blocks. |
76 | 70 |
|
77 |
| -def not32(i): |
78 |
| - i_str = format(i,'032b') |
79 |
| - new_str = '' |
80 |
| - for c in i_str: |
81 |
| - new_str += '1' if c=='0' else '0' |
82 |
| - return int(new_str,2) |
| 71 | + Arguments: |
| 72 | + bitString {[string]} -- [binary string >= 512] |
| 73 | + """ |
83 | 74 |
|
84 |
| -def sum32(a,b): |
85 |
| - return (a + b) % 2**32 |
| 75 | + currPos = 0 |
| 76 | + while currPos < len(bitString): |
| 77 | + currPart = bitString[currPos:currPos+512] |
| 78 | + mySplits = [] |
| 79 | + for i in range(16): |
| 80 | + mySplits.append(int(rearrange(currPart[32*i:32*i+32]), 2)) |
| 81 | + yield mySplits |
| 82 | + currPos += 512 |
| 83 | + |
| 84 | + |
| 85 | +def not32(i): |
| 86 | + ''' |
| 87 | + >>> not32(34) |
| 88 | + 4294967261 |
| 89 | + ''' |
| 90 | + i_str = format(i, '032b') |
| 91 | + new_str = '' |
| 92 | + for c in i_str: |
| 93 | + new_str += '1' if c == '0' else '0' |
| 94 | + return int(new_str, 2) |
| 95 | + |
| 96 | +def sum32(a, b): |
| 97 | + ''' |
| 98 | + |
| 99 | + ''' |
| 100 | + return (a + b) % 2**32 |
| 101 | + |
| 102 | +def leftrot32(i, s): |
| 103 | + return (i << s) ^ (i >> (32-s)) |
86 | 104 |
|
87 |
| -def leftrot32(i,s): |
88 |
| - return (i << s) ^ (i >> (32-s)) |
89 | 105 |
|
90 | 106 | def md5me(testString):
|
91 |
| - """[summary] |
92 |
| - Returns a 32-bit hash code of the string 'testString' |
93 |
| -
|
94 |
| - Arguments: |
95 |
| - testString {[string]} -- [message] |
96 |
| - """ |
97 |
| - |
98 |
| - bs ='' |
99 |
| - for i in testString: |
100 |
| - bs += format(ord(i),'08b') |
101 |
| - bs = pad(bs) |
102 |
| - |
103 |
| - tvals = [int(2**32 * abs(math.sin(i+1))) for i in range(64)] |
104 |
| - |
105 |
| - a0 = 0x67452301 |
106 |
| - b0 = 0xefcdab89 |
107 |
| - c0 = 0x98badcfe |
108 |
| - d0 = 0x10325476 |
109 |
| - |
110 |
| - s = [7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, \ |
111 |
| - 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, \ |
112 |
| - 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, \ |
113 |
| - 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21 ] |
114 |
| - |
115 |
| - for m in getBlock(bs): |
116 |
| - A = a0 |
117 |
| - B = b0 |
118 |
| - C = c0 |
119 |
| - D = d0 |
120 |
| - for i in range(64): |
121 |
| - if i <= 15: |
122 |
| - #f = (B & C) | (not32(B) & D) |
123 |
| - f = D ^ (B & (C ^ D)) |
124 |
| - g = i |
125 |
| - elif i<= 31: |
126 |
| - #f = (D & B) | (not32(D) & C) |
127 |
| - f = C ^ (D & (B ^ C)) |
128 |
| - g = (5*i+1) % 16 |
129 |
| - elif i <= 47: |
130 |
| - f = B ^ C ^ D |
131 |
| - g = (3*i+5) % 16 |
132 |
| - else: |
133 |
| - f = C ^ (B | not32(D)) |
134 |
| - g = (7*i) % 16 |
135 |
| - dtemp = D |
136 |
| - D = C |
137 |
| - C = B |
138 |
| - B = sum32(B,leftrot32((A + f + tvals[i] + m[g]) % 2**32, s[i])) |
139 |
| - A = dtemp |
140 |
| - a0 = sum32(a0, A) |
141 |
| - b0 = sum32(b0, B) |
142 |
| - c0 = sum32(c0, C) |
143 |
| - d0 = sum32(d0, D) |
144 |
| - |
145 |
| - digest = reformatHex(a0) + reformatHex(b0) + reformatHex(c0) + reformatHex(d0) |
146 |
| - return digest |
| 107 | + """[summary] |
| 108 | + Returns a 32-bit hash code of the string 'testString' |
| 109 | +
|
| 110 | + Arguments: |
| 111 | + testString {[string]} -- [message] |
| 112 | + """ |
| 113 | + |
| 114 | + bs = '' |
| 115 | + for i in testString: |
| 116 | + bs += format(ord(i), '08b') |
| 117 | + bs = pad(bs) |
| 118 | + |
| 119 | + tvals = [int(2**32 * abs(math.sin(i+1))) for i in range(64)] |
| 120 | + |
| 121 | + a0 = 0x67452301 |
| 122 | + b0 = 0xefcdab89 |
| 123 | + c0 = 0x98badcfe |
| 124 | + d0 = 0x10325476 |
| 125 | + |
| 126 | + s = [7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, |
| 127 | + 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, \ |
| 128 | + 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, \ |
| 129 | + 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21 ] |
| 130 | + |
| 131 | + for m in getBlock(bs): |
| 132 | + A = a0 |
| 133 | + B = b0 |
| 134 | + C = c0 |
| 135 | + D = d0 |
| 136 | + for i in range(64): |
| 137 | + if i <= 15: |
| 138 | + #f = (B & C) | (not32(B) & D) |
| 139 | + f = D ^ (B & (C ^ D)) |
| 140 | + g = i |
| 141 | + elif i <= 31: |
| 142 | + #f = (D & B) | (not32(D) & C) |
| 143 | + f = C ^ (D & (B ^ C)) |
| 144 | + g = (5*i+1) % 16 |
| 145 | + elif i <= 47: |
| 146 | + f = B ^ C ^ D |
| 147 | + g = (3*i+5) % 16 |
| 148 | + else: |
| 149 | + f = C ^ (B | not32(D)) |
| 150 | + g = (7*i) % 16 |
| 151 | + dtemp = D |
| 152 | + D = C |
| 153 | + C = B |
| 154 | + B = sum32(B, leftrot32((A + f + tvals[i] + m[g]) % 2**32, s[i])) |
| 155 | + A = dtemp |
| 156 | + a0 = sum32(a0, A) |
| 157 | + b0 = sum32(b0, B) |
| 158 | + c0 = sum32(c0, C) |
| 159 | + d0 = sum32(d0, D) |
| 160 | + |
| 161 | + digest = reformatHex(a0) + reformatHex(b0) + \ |
| 162 | + reformatHex(c0) + reformatHex(d0) |
| 163 | + return digest |
| 164 | + |
147 | 165 |
|
148 | 166 | def test():
|
149 |
| - assert md5me("") == "d41d8cd98f00b204e9800998ecf8427e" |
150 |
| - assert md5me("The quick brown fox jumps over the lazy dog") == "9e107d9d372bb6826bd81d3542a419d6" |
151 |
| - print("Success.") |
| 167 | + assert md5me("") == "d41d8cd98f00b204e9800998ecf8427e" |
| 168 | + assert md5me( |
| 169 | + "The quick brown fox jumps over the lazy dog") == "9e107d9d372bb6826bd81d3542a419d6" |
| 170 | + print("Success.") |
152 | 171 |
|
153 | 172 |
|
154 | 173 | if __name__ == "__main__":
|
155 |
| - test() |
| 174 | + test() |
| 175 | + import doctest |
| 176 | + doctest.testmod() |
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