1 package org.bouncycastle.crypto.digests; 2 3 4 /** 5 * implementation of MD5 as outlined in "Handbook of Applied Cryptography", pages 346 - 347. 6 */ 7 public class MD5Digest 8 extends GeneralDigest 9 { 10 private static final int DIGEST_LENGTH = 16; 11 12 private int H1, H2, H3, H4; // IV's 13 14 private int[] X = new int[16]; 15 private int xOff; 16 17 /** 18 * Standard constructor 19 */ MD5Digest()20 public MD5Digest() 21 { 22 reset(); 23 } 24 25 /** 26 * Copy constructor. This will copy the state of the provided 27 * message digest. 28 */ MD5Digest(MD5Digest t)29 public MD5Digest(MD5Digest t) 30 { 31 super(t); 32 33 H1 = t.H1; 34 H2 = t.H2; 35 H3 = t.H3; 36 H4 = t.H4; 37 38 System.arraycopy(t.X, 0, X, 0, t.X.length); 39 xOff = t.xOff; 40 } 41 getAlgorithmName()42 public String getAlgorithmName() 43 { 44 return "MD5"; 45 } 46 getDigestSize()47 public int getDigestSize() 48 { 49 return DIGEST_LENGTH; 50 } 51 processWord( byte[] in, int inOff)52 protected void processWord( 53 byte[] in, 54 int inOff) 55 { 56 X[xOff++] = (in[inOff] & 0xff) | ((in[inOff + 1] & 0xff) << 8) 57 | ((in[inOff + 2] & 0xff) << 16) | ((in[inOff + 3] & 0xff) << 24); 58 59 if (xOff == 16) 60 { 61 processBlock(); 62 } 63 } 64 processLength( long bitLength)65 protected void processLength( 66 long bitLength) 67 { 68 if (xOff > 14) 69 { 70 processBlock(); 71 } 72 73 X[14] = (int)(bitLength & 0xffffffff); 74 X[15] = (int)(bitLength >>> 32); 75 } 76 unpackWord( int word, byte[] out, int outOff)77 private void unpackWord( 78 int word, 79 byte[] out, 80 int outOff) 81 { 82 out[outOff] = (byte)word; 83 out[outOff + 1] = (byte)(word >>> 8); 84 out[outOff + 2] = (byte)(word >>> 16); 85 out[outOff + 3] = (byte)(word >>> 24); 86 } 87 doFinal( byte[] out, int outOff)88 public int doFinal( 89 byte[] out, 90 int outOff) 91 { 92 finish(); 93 94 unpackWord(H1, out, outOff); 95 unpackWord(H2, out, outOff + 4); 96 unpackWord(H3, out, outOff + 8); 97 unpackWord(H4, out, outOff + 12); 98 99 reset(); 100 101 return DIGEST_LENGTH; 102 } 103 104 /** 105 * reset the chaining variables to the IV values. 106 */ reset()107 public void reset() 108 { 109 super.reset(); 110 111 H1 = 0x67452301; 112 H2 = 0xefcdab89; 113 H3 = 0x98badcfe; 114 H4 = 0x10325476; 115 116 xOff = 0; 117 118 for (int i = 0; i != X.length; i++) 119 { 120 X[i] = 0; 121 } 122 } 123 124 // 125 // round 1 left rotates 126 // 127 private static final int S11 = 7; 128 private static final int S12 = 12; 129 private static final int S13 = 17; 130 private static final int S14 = 22; 131 132 // 133 // round 2 left rotates 134 // 135 private static final int S21 = 5; 136 private static final int S22 = 9; 137 private static final int S23 = 14; 138 private static final int S24 = 20; 139 140 // 141 // round 3 left rotates 142 // 143 private static final int S31 = 4; 144 private static final int S32 = 11; 145 private static final int S33 = 16; 146 private static final int S34 = 23; 147 148 // 149 // round 4 left rotates 150 // 151 private static final int S41 = 6; 152 private static final int S42 = 10; 153 private static final int S43 = 15; 154 private static final int S44 = 21; 155 156 /* 157 * rotate int x left n bits. 158 */ rotateLeft( int x, int n)159 private int rotateLeft( 160 int x, 161 int n) 162 { 163 return (x << n) | (x >>> (32 - n)); 164 } 165 166 /* 167 * F, G, H and I are the basic MD5 functions. 168 */ F( int u, int v, int w)169 private int F( 170 int u, 171 int v, 172 int w) 173 { 174 return (u & v) | (~u & w); 175 } 176 G( int u, int v, int w)177 private int G( 178 int u, 179 int v, 180 int w) 181 { 182 return (u & w) | (v & ~w); 183 } 184 H( int u, int v, int w)185 private int H( 186 int u, 187 int v, 188 int w) 189 { 190 return u ^ v ^ w; 191 } 192 K( int u, int v, int w)193 private int K( 194 int u, 195 int v, 196 int w) 197 { 198 return v ^ (u | ~w); 199 } 200 processBlock()201 protected void processBlock() 202 { 203 int a = H1; 204 int b = H2; 205 int c = H3; 206 int d = H4; 207 208 // 209 // Round 1 - F cycle, 16 times. 210 // 211 a = rotateLeft(a + F(b, c, d) + X[ 0] + 0xd76aa478, S11) + b; 212 d = rotateLeft(d + F(a, b, c) + X[ 1] + 0xe8c7b756, S12) + a; 213 c = rotateLeft(c + F(d, a, b) + X[ 2] + 0x242070db, S13) + d; 214 b = rotateLeft(b + F(c, d, a) + X[ 3] + 0xc1bdceee, S14) + c; 215 a = rotateLeft(a + F(b, c, d) + X[ 4] + 0xf57c0faf, S11) + b; 216 d = rotateLeft(d + F(a, b, c) + X[ 5] + 0x4787c62a, S12) + a; 217 c = rotateLeft(c + F(d, a, b) + X[ 6] + 0xa8304613, S13) + d; 218 b = rotateLeft(b + F(c, d, a) + X[ 7] + 0xfd469501, S14) + c; 219 a = rotateLeft(a + F(b, c, d) + X[ 8] + 0x698098d8, S11) + b; 220 d = rotateLeft(d + F(a, b, c) + X[ 9] + 0x8b44f7af, S12) + a; 221 c = rotateLeft(c + F(d, a, b) + X[10] + 0xffff5bb1, S13) + d; 222 b = rotateLeft(b + F(c, d, a) + X[11] + 0x895cd7be, S14) + c; 223 a = rotateLeft(a + F(b, c, d) + X[12] + 0x6b901122, S11) + b; 224 d = rotateLeft(d + F(a, b, c) + X[13] + 0xfd987193, S12) + a; 225 c = rotateLeft(c + F(d, a, b) + X[14] + 0xa679438e, S13) + d; 226 b = rotateLeft(b + F(c, d, a) + X[15] + 0x49b40821, S14) + c; 227 228 // 229 // Round 2 - G cycle, 16 times. 230 // 231 a = rotateLeft(a + G(b, c, d) + X[ 1] + 0xf61e2562, S21) + b; 232 d = rotateLeft(d + G(a, b, c) + X[ 6] + 0xc040b340, S22) + a; 233 c = rotateLeft(c + G(d, a, b) + X[11] + 0x265e5a51, S23) + d; 234 b = rotateLeft(b + G(c, d, a) + X[ 0] + 0xe9b6c7aa, S24) + c; 235 a = rotateLeft(a + G(b, c, d) + X[ 5] + 0xd62f105d, S21) + b; 236 d = rotateLeft(d + G(a, b, c) + X[10] + 0x02441453, S22) + a; 237 c = rotateLeft(c + G(d, a, b) + X[15] + 0xd8a1e681, S23) + d; 238 b = rotateLeft(b + G(c, d, a) + X[ 4] + 0xe7d3fbc8, S24) + c; 239 a = rotateLeft(a + G(b, c, d) + X[ 9] + 0x21e1cde6, S21) + b; 240 d = rotateLeft(d + G(a, b, c) + X[14] + 0xc33707d6, S22) + a; 241 c = rotateLeft(c + G(d, a, b) + X[ 3] + 0xf4d50d87, S23) + d; 242 b = rotateLeft(b + G(c, d, a) + X[ 8] + 0x455a14ed, S24) + c; 243 a = rotateLeft(a + G(b, c, d) + X[13] + 0xa9e3e905, S21) + b; 244 d = rotateLeft(d + G(a, b, c) + X[ 2] + 0xfcefa3f8, S22) + a; 245 c = rotateLeft(c + G(d, a, b) + X[ 7] + 0x676f02d9, S23) + d; 246 b = rotateLeft(b + G(c, d, a) + X[12] + 0x8d2a4c8a, S24) + c; 247 248 // 249 // Round 3 - H cycle, 16 times. 250 // 251 a = rotateLeft(a + H(b, c, d) + X[ 5] + 0xfffa3942, S31) + b; 252 d = rotateLeft(d + H(a, b, c) + X[ 8] + 0x8771f681, S32) + a; 253 c = rotateLeft(c + H(d, a, b) + X[11] + 0x6d9d6122, S33) + d; 254 b = rotateLeft(b + H(c, d, a) + X[14] + 0xfde5380c, S34) + c; 255 a = rotateLeft(a + H(b, c, d) + X[ 1] + 0xa4beea44, S31) + b; 256 d = rotateLeft(d + H(a, b, c) + X[ 4] + 0x4bdecfa9, S32) + a; 257 c = rotateLeft(c + H(d, a, b) + X[ 7] + 0xf6bb4b60, S33) + d; 258 b = rotateLeft(b + H(c, d, a) + X[10] + 0xbebfbc70, S34) + c; 259 a = rotateLeft(a + H(b, c, d) + X[13] + 0x289b7ec6, S31) + b; 260 d = rotateLeft(d + H(a, b, c) + X[ 0] + 0xeaa127fa, S32) + a; 261 c = rotateLeft(c + H(d, a, b) + X[ 3] + 0xd4ef3085, S33) + d; 262 b = rotateLeft(b + H(c, d, a) + X[ 6] + 0x04881d05, S34) + c; 263 a = rotateLeft(a + H(b, c, d) + X[ 9] + 0xd9d4d039, S31) + b; 264 d = rotateLeft(d + H(a, b, c) + X[12] + 0xe6db99e5, S32) + a; 265 c = rotateLeft(c + H(d, a, b) + X[15] + 0x1fa27cf8, S33) + d; 266 b = rotateLeft(b + H(c, d, a) + X[ 2] + 0xc4ac5665, S34) + c; 267 268 // 269 // Round 4 - K cycle, 16 times. 270 // 271 a = rotateLeft(a + K(b, c, d) + X[ 0] + 0xf4292244, S41) + b; 272 d = rotateLeft(d + K(a, b, c) + X[ 7] + 0x432aff97, S42) + a; 273 c = rotateLeft(c + K(d, a, b) + X[14] + 0xab9423a7, S43) + d; 274 b = rotateLeft(b + K(c, d, a) + X[ 5] + 0xfc93a039, S44) + c; 275 a = rotateLeft(a + K(b, c, d) + X[12] + 0x655b59c3, S41) + b; 276 d = rotateLeft(d + K(a, b, c) + X[ 3] + 0x8f0ccc92, S42) + a; 277 c = rotateLeft(c + K(d, a, b) + X[10] + 0xffeff47d, S43) + d; 278 b = rotateLeft(b + K(c, d, a) + X[ 1] + 0x85845dd1, S44) + c; 279 a = rotateLeft(a + K(b, c, d) + X[ 8] + 0x6fa87e4f, S41) + b; 280 d = rotateLeft(d + K(a, b, c) + X[15] + 0xfe2ce6e0, S42) + a; 281 c = rotateLeft(c + K(d, a, b) + X[ 6] + 0xa3014314, S43) + d; 282 b = rotateLeft(b + K(c, d, a) + X[13] + 0x4e0811a1, S44) + c; 283 a = rotateLeft(a + K(b, c, d) + X[ 4] + 0xf7537e82, S41) + b; 284 d = rotateLeft(d + K(a, b, c) + X[11] + 0xbd3af235, S42) + a; 285 c = rotateLeft(c + K(d, a, b) + X[ 2] + 0x2ad7d2bb, S43) + d; 286 b = rotateLeft(b + K(c, d, a) + X[ 9] + 0xeb86d391, S44) + c; 287 288 H1 += a; 289 H2 += b; 290 H3 += c; 291 H4 += d; 292 293 // 294 // reset the offset and clean out the word buffer. 295 // 296 xOff = 0; 297 for (int i = 0; i != X.length; i++) 298 { 299 X[i] = 0; 300 } 301 } 302 } 303