import java.util.*;
class MD5
{
private static final int INIT_A = 0x67452301;
private static final int INIT_B = (int) 0xEFCDAB89L;
private static final int INIT_C = (int) 0x98BADCFEL;
private static final int INIT_D = 0x10325476;
private static final int[] SHIFT_AMTS = { 7, 12, 17, 22, 5, 9, 14, 20, 4, 11, 16, 23, 6, 10, 15, 21 };
private static final int[] TABLE_T = new int[64];
static
{
for (int i = 0; i < 64; i++)
TABLE_T[i] = (int) (long) ((1L << 32) * Math.abs(Math.sin(i + 1)));
}
public static byte[] computeMD5(byte[] message)
{
int messageLenBytes = message.length;
int numBlocks = ((messageLenBytes + 8) >>> 6) + 1;
int totalLen = numBlocks << 6;
byte[] paddingBytes = new byte[totalLen - messageLenBytes];
paddingBytes[0] = (byte) 0x80;
long messageLenBits = (long) messageLenBytes << 3;
for (int i = 0; i < 8; i++)
{
paddingBytes[paddingBytes.length - 8 + i] = (byte) messageLenBits;
messageLenBits >>>= 8;
}
int a = INIT_A;
int b = INIT_B;
int c = INIT_C;
int d = INIT_D;
int[] buffer = new int[16];
for (int i = 0; i < numBlocks; i++)
{
int index = i << 6;
for (int j = 0; j < 64; j++, index++)
buffer[j >>> 2] = ((int) ((index < messageLenBytes) ? message[index]
: paddingBytes[index - messageLenBytes]) << 24)
| (buffer[j >>> 2] >>> 8);
int originalA = a;
int originalB = b;
int originalC = c;
int originalD = d;
for (int j = 0; j < 64; j++)
{
int div16 = j >>> 4;
int f = 0;
int bufferIndex = j;
switch (div16)
{
case 0:
f = (b & c) | (~b & d);
break;
case 1:
f = (b & d) | (c & ~d);
bufferIndex = (bufferIndex * 5 + 1) & 0x0F;
break;
case 2:
f = b ^ c ^ d;
bufferIndex = (bufferIndex * 3 + 5) & 0x0F;
break;
case 3:
f = c ^ (b | ~d);
bufferIndex = (bufferIndex * 7) & 0x0F;
break;
}
int temp = b
+ Integer.rotateLeft(a + f + buffer[bufferIndex]
+ TABLE_T[j],
SHIFT_AMTS[(div16 << 2) | (j & 3)]);
a = d;
d = c;
c = b;
b = temp;
}
a += originalA;
b += originalB;
c += originalC;
d += originalD;
}
byte[] md5 = new byte[16];
int count = 0;
for (int i = 0; i < 4; i++)
{
int n = (i == 0) ? a : ((i == 1) ? b : ((i == 2) ? c : d));
for (int j = 0; j < 4; j++)
{
md5[count++] = (byte) n;
n >>>= 8;
}
}
return md5;
}
public static String toHexString(byte[] b)
{
StringBuilder sb = new StringBuilder();
for (int i = 0; i < b.length; i++)
{
sb.append(String.format("%02X", b[i] & 0xFF));
}
return sb.toString();
}
public static void main(String[] args)
{
String[] testStrings= new String[4];
Scanner dc= new Scanner(System.in);
System.out.println("Enter 4 input strings:");
for(int i=0;i<4;i++)
testStrings[i]= dc.nextLine();
for (String in : testStrings)
System.out.println("0x" + toHexString(computeMD5(in.getBytes()))
+ " <== \"" + in + "\"");
return;
}
}
/*
Output:
codept@codept-05 ~/Desktop $ java MD5
Enter 4 input strings:
Hello World
MD5
keyword
beco
0xB10A8DB164E0754105B7A99BE72E3FE5 <== "Hello World"
0x7F138A09169B250E9DCB378140907378 <== "MD5"
0xD7DF5B64DF1181EF1D62D646A13AA860 <== "keyword"
0x43C348CF5E74DAB638CF1251DFD41803 <== "beco"
codept@codept-05 ~/Desktop $
*/
class MD5
{
private static final int INIT_A = 0x67452301;
private static final int INIT_B = (int) 0xEFCDAB89L;
private static final int INIT_C = (int) 0x98BADCFEL;
private static final int INIT_D = 0x10325476;
private static final int[] SHIFT_AMTS = { 7, 12, 17, 22, 5, 9, 14, 20, 4, 11, 16, 23, 6, 10, 15, 21 };
private static final int[] TABLE_T = new int[64];
static
{
for (int i = 0; i < 64; i++)
TABLE_T[i] = (int) (long) ((1L << 32) * Math.abs(Math.sin(i + 1)));
}
public static byte[] computeMD5(byte[] message)
{
int messageLenBytes = message.length;
int numBlocks = ((messageLenBytes + 8) >>> 6) + 1;
int totalLen = numBlocks << 6;
byte[] paddingBytes = new byte[totalLen - messageLenBytes];
paddingBytes[0] = (byte) 0x80;
long messageLenBits = (long) messageLenBytes << 3;
for (int i = 0; i < 8; i++)
{
paddingBytes[paddingBytes.length - 8 + i] = (byte) messageLenBits;
messageLenBits >>>= 8;
}
int a = INIT_A;
int b = INIT_B;
int c = INIT_C;
int d = INIT_D;
int[] buffer = new int[16];
for (int i = 0; i < numBlocks; i++)
{
int index = i << 6;
for (int j = 0; j < 64; j++, index++)
buffer[j >>> 2] = ((int) ((index < messageLenBytes) ? message[index]
: paddingBytes[index - messageLenBytes]) << 24)
| (buffer[j >>> 2] >>> 8);
int originalA = a;
int originalB = b;
int originalC = c;
int originalD = d;
for (int j = 0; j < 64; j++)
{
int div16 = j >>> 4;
int f = 0;
int bufferIndex = j;
switch (div16)
{
case 0:
f = (b & c) | (~b & d);
break;
case 1:
f = (b & d) | (c & ~d);
bufferIndex = (bufferIndex * 5 + 1) & 0x0F;
break;
case 2:
f = b ^ c ^ d;
bufferIndex = (bufferIndex * 3 + 5) & 0x0F;
break;
case 3:
f = c ^ (b | ~d);
bufferIndex = (bufferIndex * 7) & 0x0F;
break;
}
int temp = b
+ Integer.rotateLeft(a + f + buffer[bufferIndex]
+ TABLE_T[j],
SHIFT_AMTS[(div16 << 2) | (j & 3)]);
a = d;
d = c;
c = b;
b = temp;
}
a += originalA;
b += originalB;
c += originalC;
d += originalD;
}
byte[] md5 = new byte[16];
int count = 0;
for (int i = 0; i < 4; i++)
{
int n = (i == 0) ? a : ((i == 1) ? b : ((i == 2) ? c : d));
for (int j = 0; j < 4; j++)
{
md5[count++] = (byte) n;
n >>>= 8;
}
}
return md5;
}
public static String toHexString(byte[] b)
{
StringBuilder sb = new StringBuilder();
for (int i = 0; i < b.length; i++)
{
sb.append(String.format("%02X", b[i] & 0xFF));
}
return sb.toString();
}
public static void main(String[] args)
{
String[] testStrings= new String[4];
Scanner dc= new Scanner(System.in);
System.out.println("Enter 4 input strings:");
for(int i=0;i<4;i++)
testStrings[i]= dc.nextLine();
for (String in : testStrings)
System.out.println("0x" + toHexString(computeMD5(in.getBytes()))
+ " <== \"" + in + "\"");
return;
}
}
/*
Output:
codept@codept-05 ~/Desktop $ java MD5
Enter 4 input strings:
Hello World
MD5
keyword
beco
0xB10A8DB164E0754105B7A99BE72E3FE5 <== "Hello World"
0x7F138A09169B250E9DCB378140907378 <== "MD5"
0xD7DF5B64DF1181EF1D62D646A13AA860 <== "keyword"
0x43C348CF5E74DAB638CF1251DFD41803 <== "beco"
codept@codept-05 ~/Desktop $
*/
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