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Приветствую. Пишу реализацию md5 на Java. Вроде все делаю по описанию алгоритма, но выходит что-то не так. Такое чувство, что от входных данных вобще ничего не зависит. Есть подозрение, что проблема из-за отсутствия беззнаковых ТД, либо что где-то косячу с обратным порядком байт в слове. Убил весь день прежде, чем просить о помощи. Помогите, пожалуйста, исправить. md5.java | Код |
package security;
import java.util.ArrayList;
import java.util.List;
public final class md5
{
private static final int initialA = 0x01234567;
private static final int initialB = 0x89abcdef;
private static final int initialC = 0xfedcba98;
private static final int initialD = 0x76543210;
private static int getT(int i)
{
return (int)Math.floor((4294967296L * Math.abs(Math.sin(i))));
}
private static byte[] getWordBytes(int word)
{
byte[] bytes = new byte[4];
bytes[0] = (byte)(word & 0xFF);
bytes[1] = (byte)((word & 0xFF00) >> 8);
bytes[2] = (byte)((word & 0xFF0000) >> 16);
bytes[3] = (byte)((word & 0xFF000000) >> 24);
return bytes;
}
private static int F(int x, int y, int z)
{
return (x & y) | (~x & z);
}
private static int G(int x, int y, int z)
{
return (x & z) | (y & ~z);
}
private static int H(int x, int y, int z)
{
return x ^ y ^ z;
}
private static int I(int x, int y, int z)
{
return (x & y) | (~x & z);
}
private static List<Byte> normilze(byte[] input)
{
List<Byte> message = new ArrayList<Byte>();
for(int i = 0; i < input.length; ++i)
{
message.add(input[i]);
}
message.add((byte) 0x80);
while(message.size() % (512 / 8) != (448 / 8))
{
message.add((byte)0x00);
}
long msgSize = input.length * 8;
int lowWord = (int)(msgSize & 0xFFFFFFFFL);
int highWord = (int)((msgSize & 0xFFFFFFFF00000000L) >> 32);
byte[] sizeBytes = getWordBytes(lowWord);
for(int i = 0; i < 4; ++i)
{
message.add(sizeBytes[i]);
}
sizeBytes = getWordBytes(highWord);
for(int i = 0; i < 4; ++i)
{
message.add(sizeBytes[i]);
}
return message;
}
private static int rol1(int word)
{
byte tmp = (byte)((word & 0x80000000) >> 32);
word = word << 1;
if(tmp == 1)
{
word |= 1;
}
else
{
word &= 0;
}
return word;
}
private static int rol(int word, int n)
{
for(int i = 0; i < n; ++i)
{
word = rol1(word);
}
return word;
}
private static int getWord(List<Byte> message, int n, int k)
{
byte[] bytes = new byte[4];
bytes[0] = message.get(n * 16 + k * 4 + 0);
bytes[1] = message.get(n * 16 + k * 4 + 1);
bytes[2] = message.get(n * 16 + k * 4 + 2);
bytes[3] = message.get(n * 16 + k * 4 + 3);
int result = (bytes[3] << 24) + (bytes[2] << 16) + (bytes[1] << 8) + bytes[0];
return result;
}
private static int nextRound(int A, int B, int C, int D, int k, int s, int i, List<Byte> message, int n)
{
int tmp;
if(i < 16)
{
tmp = F(B, C, D);
}
else if(i < 32)
{
tmp = G(B, C, D);
}
else if(i < 48)
{
tmp = H(B, C, D);
}
else
{
tmp = I(B, C, D);
}
return B + rol((A + tmp + getWord(message, n, k) + getT(i)), s);
}
public static int[] getMD5(byte[] input)
{
int A = initialA;
int B = initialB;
int C = initialC;
int D = initialD;
int oldA = A;
int oldB = B;
int oldC = C;
int oldD = D;
List<Byte> message = normilze(input);
for(int i = 0; i < (message.size() / (512 / 8)); ++i)
{
oldA = A;
oldB = B;
oldC = C;
oldD = D;
A = nextRound(A, B, C, D, 0, 7, 1, message, i);
D = nextRound(D, A, B, C, 1, 12, 2, message, i);
C = nextRound(C, D, A, B, 2, 17, 3, message, i);
B = nextRound(B, C, D, A, 3, 22, 4, message, i);
A = nextRound(A, B, C, D, 4, 7, 5, message, i);
D = nextRound(D, A, B, C, 5, 12, 6, message, i);
C = nextRound(C, D, A, B, 6, 17, 7, message, i);
D = nextRound(B, C, D, A, 7, 22, 8, message, i);
A = nextRound(A, B, C, D, 8, 7, 9, message, i);
D = nextRound(D, A, B, C, 9, 12, 10, message, i);
C = nextRound(C, D, A, B, 10, 17, 11, message, i);
B = nextRound(B, C, D, A, 11, 22, 12, message, i);
A = nextRound(A, B, C, D, 12, 7, 13, message, i);
D = nextRound(D, A, B, C, 13, 12, 14, message, i);
C = nextRound(C, D, A, B, 14, 17, 15, message, i);
B = nextRound(B, C, D, A, 15, 22, 16, message, i);
A = nextRound(A,B,C,D,1,5,17, message, i);
D = nextRound(D,A,B,C,6,9,18, message, i);
C = nextRound(C,D,A,B,11,14,19, message, i);
B = nextRound(B,C,D,A,0,20,20, message, i);
A = nextRound(A,B,C,D,5, 5, 21, message, i);
D = nextRound(D,A,B,C,10,9,22, message, i);
C = nextRound(C,D,A,B,15,14,23, message, i);
B = nextRound(B,C,D,A,4,20,24, message, i);
C = nextRound(A,B,C,D,9,5,25, message, i);
D = nextRound(D,A,B,C,14, 9, 26, message, i);
C = nextRound(C,D,A,B,3, 14, 27, message, i);
B = nextRound(B,C,D,A,8,20,28, message, i);
A = nextRound(A,B,C,D, 13, 5, 29, message, i);
D = nextRound(D,A,B,C,2,9,30, message, i);
C = nextRound(C,D,A,B,7,14,31, message, i);
B = nextRound(B,C,D,A,12,20,32, message, i);
A = nextRound(A,B,C,D, 5, 4, 33, message, i);
D = nextRound(D,A,B,C,8,11,34, message, i);
C = nextRound(C,D,A,B, 11, 16, 35, message, i);
B = nextRound(B,C,D,A, 14, 23, 36, message, i);
A = nextRound(A,B,C,D, 1, 4, 37, message, i);
D = nextRound(D,A,B,C, 4, 11, 38, message, i);
C = nextRound(C,D,A,B,7, 16, 39, message, i);
B = nextRound(B,C,D,A, 10, 23, 40, message, i);
A = nextRound(A,B,C,D, 13, 4, 41, message, i);
D = nextRound(D,A,B,C, 0, 11, 42, message, i);
C = nextRound(C,D,A,B, 3, 16, 43, message, i);
B = nextRound(B,C,D,A, 6, 23, 44, message, i);
A = nextRound(A,B,C,D, 9, 4, 45, message, i);
D = nextRound(D,A,B,C, 12, 11, 46, message, i);
C = nextRound(C,D,A,B, 15, 16, 47, message, i);
B = nextRound(B,C,D,A, 2, 23, 48, message, i);
A = nextRound(A,B,C,D, 0, 6, 49, message, i);
D = nextRound(D,A,B,C, 7, 10, 50, message, i);
C = nextRound(C,D,A,B, 14, 15, 51, message, i);
B = nextRound(B,C,D,A, 5, 21, 52, message, i);
A = nextRound(A,B,C,D, 12, 6, 53, message, i);
D = nextRound(D,A,B,C, 3, 10, 54, message, i);
C = nextRound(C,D,A,B, 10, 15, 55, message, i);
B = nextRound(B,C,D,A, 1, 21, 56, message, i);
A = nextRound(A,B,C,D, 8, 6, 57, message, i);
D = nextRound(D,A,B,C, 15, 10, 58, message, i);
C = nextRound(C,D,A,B, 6, 15, 59, message, i);
B = nextRound(B,C,D,A, 13, 21, 60, message, i);
A = nextRound(A,B,C,D, 4, 6, 61, message, i);
D = nextRound(D,A,B,C, 11, 10, 62, message, i);
C = nextRound(C,D,A,B, 2, 15, 63, message, i);
B = nextRound(B,C,D,A, 9, 21, 64, message, i);
A += oldA;
B += oldB;
C += oldC;
D += oldD;
}
int[] result = new int[4];
result[3] = A;
result[2] = B;
result[1] = C;
result[0] = D;
return result;
}
}
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StartPoint.java | Код |
package program;
import security.md5;
public final class StartPoint
{
/**
* @param args
*/
public static void main(String[] args)
{
int[] result = md5.getMD5(new byte[] {0x68, 0x61, 0x62, 0x72, 0x61, 0x68, 0x61, 0x62, 0x72});
System.out.printf("%8x%8x%8x%8x", result[0], result[1], result[2], result[3]);
}
}
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Извините за убогие имена функций/переменных. Делал единообразно с документацией. Это сообщение отредактировал(а) BHYCHIK - 9.3.2013, 01:01 |
Реализация md5, Помогите найти глюк 
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