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Diffstat (limited to 'core/src/main/java/org/spongycastle/crypto/digests/MD4Digest.java')
| -rw-r--r-- | core/src/main/java/org/spongycastle/crypto/digests/MD4Digest.java | 291 |
1 files changed, 291 insertions, 0 deletions
diff --git a/core/src/main/java/org/spongycastle/crypto/digests/MD4Digest.java b/core/src/main/java/org/spongycastle/crypto/digests/MD4Digest.java new file mode 100644 index 00000000..9faf0025 --- /dev/null +++ b/core/src/main/java/org/spongycastle/crypto/digests/MD4Digest.java @@ -0,0 +1,291 @@ +package org.spongycastle.crypto.digests; + + +import org.spongycastle.util.Memoable; + +/** + * implementation of MD4 as RFC 1320 by R. Rivest, MIT Laboratory for + * Computer Science and RSA Data Security, Inc. + * <p> + * <b>NOTE</b>: This algorithm is only included for backwards compatability + * with legacy applications, it's not secure, don't use it for anything new! + */ +public class MD4Digest + extends GeneralDigest +{ + private static final int DIGEST_LENGTH = 16; + + private int H1, H2, H3, H4; // IV's + + private int[] X = new int[16]; + private int xOff; + + /** + * Standard constructor + */ + public MD4Digest() + { + reset(); + } + + /** + * Copy constructor. This will copy the state of the provided + * message digest. + */ + public MD4Digest(MD4Digest t) + { + super(t); + + copyIn(t); + } + + private void copyIn(MD4Digest t) + { + super.copyIn(t); + + H1 = t.H1; + H2 = t.H2; + H3 = t.H3; + H4 = t.H4; + + System.arraycopy(t.X, 0, X, 0, t.X.length); + xOff = t.xOff; + } + + public String getAlgorithmName() + { + return "MD4"; + } + + public int getDigestSize() + { + return DIGEST_LENGTH; + } + + protected void processWord( + byte[] in, + int inOff) + { + X[xOff++] = (in[inOff] & 0xff) | ((in[inOff + 1] & 0xff) << 8) + | ((in[inOff + 2] & 0xff) << 16) | ((in[inOff + 3] & 0xff) << 24); + + if (xOff == 16) + { + processBlock(); + } + } + + protected void processLength( + long bitLength) + { + if (xOff > 14) + { + processBlock(); + } + + X[14] = (int)(bitLength & 0xffffffff); + X[15] = (int)(bitLength >>> 32); + } + + private void unpackWord( + int word, + byte[] out, + int outOff) + { + out[outOff] = (byte)word; + out[outOff + 1] = (byte)(word >>> 8); + out[outOff + 2] = (byte)(word >>> 16); + out[outOff + 3] = (byte)(word >>> 24); + } + + public int doFinal( + byte[] out, + int outOff) + { + finish(); + + unpackWord(H1, out, outOff); + unpackWord(H2, out, outOff + 4); + unpackWord(H3, out, outOff + 8); + unpackWord(H4, out, outOff + 12); + + reset(); + + return DIGEST_LENGTH; + } + + /** + * reset the chaining variables to the IV values. + */ + public void reset() + { + super.reset(); + + H1 = 0x67452301; + H2 = 0xefcdab89; + H3 = 0x98badcfe; + H4 = 0x10325476; + + xOff = 0; + + for (int i = 0; i != X.length; i++) + { + X[i] = 0; + } + } + + // + // round 1 left rotates + // + private static final int S11 = 3; + private static final int S12 = 7; + private static final int S13 = 11; + private static final int S14 = 19; + + // + // round 2 left rotates + // + private static final int S21 = 3; + private static final int S22 = 5; + private static final int S23 = 9; + private static final int S24 = 13; + + // + // round 3 left rotates + // + private static final int S31 = 3; + private static final int S32 = 9; + private static final int S33 = 11; + private static final int S34 = 15; + + /* + * rotate int x left n bits. + */ + private int rotateLeft( + int x, + int n) + { + return (x << n) | (x >>> (32 - n)); + } + + /* + * F, G, H and I are the basic MD4 functions. + */ + private int F( + int u, + int v, + int w) + { + return (u & v) | (~u & w); + } + + private int G( + int u, + int v, + int w) + { + return (u & v) | (u & w) | (v & w); + } + + private int H( + int u, + int v, + int w) + { + return u ^ v ^ w; + } + + protected void processBlock() + { + int a = H1; + int b = H2; + int c = H3; + int d = H4; + + // + // Round 1 - F cycle, 16 times. + // + a = rotateLeft(a + F(b, c, d) + X[ 0], S11); + d = rotateLeft(d + F(a, b, c) + X[ 1], S12); + c = rotateLeft(c + F(d, a, b) + X[ 2], S13); + b = rotateLeft(b + F(c, d, a) + X[ 3], S14); + a = rotateLeft(a + F(b, c, d) + X[ 4], S11); + d = rotateLeft(d + F(a, b, c) + X[ 5], S12); + c = rotateLeft(c + F(d, a, b) + X[ 6], S13); + b = rotateLeft(b + F(c, d, a) + X[ 7], S14); + a = rotateLeft(a + F(b, c, d) + X[ 8], S11); + d = rotateLeft(d + F(a, b, c) + X[ 9], S12); + c = rotateLeft(c + F(d, a, b) + X[10], S13); + b = rotateLeft(b + F(c, d, a) + X[11], S14); + a = rotateLeft(a + F(b, c, d) + X[12], S11); + d = rotateLeft(d + F(a, b, c) + X[13], S12); + c = rotateLeft(c + F(d, a, b) + X[14], S13); + b = rotateLeft(b + F(c, d, a) + X[15], S14); + + // + // Round 2 - G cycle, 16 times. + // + a = rotateLeft(a + G(b, c, d) + X[ 0] + 0x5a827999, S21); + d = rotateLeft(d + G(a, b, c) + X[ 4] + 0x5a827999, S22); + c = rotateLeft(c + G(d, a, b) + X[ 8] + 0x5a827999, S23); + b = rotateLeft(b + G(c, d, a) + X[12] + 0x5a827999, S24); + a = rotateLeft(a + G(b, c, d) + X[ 1] + 0x5a827999, S21); + d = rotateLeft(d + G(a, b, c) + X[ 5] + 0x5a827999, S22); + c = rotateLeft(c + G(d, a, b) + X[ 9] + 0x5a827999, S23); + b = rotateLeft(b + G(c, d, a) + X[13] + 0x5a827999, S24); + a = rotateLeft(a + G(b, c, d) + X[ 2] + 0x5a827999, S21); + d = rotateLeft(d + G(a, b, c) + X[ 6] + 0x5a827999, S22); + c = rotateLeft(c + G(d, a, b) + X[10] + 0x5a827999, S23); + b = rotateLeft(b + G(c, d, a) + X[14] + 0x5a827999, S24); + a = rotateLeft(a + G(b, c, d) + X[ 3] + 0x5a827999, S21); + d = rotateLeft(d + G(a, b, c) + X[ 7] + 0x5a827999, S22); + c = rotateLeft(c + G(d, a, b) + X[11] + 0x5a827999, S23); + b = rotateLeft(b + G(c, d, a) + X[15] + 0x5a827999, S24); + + // + // Round 3 - H cycle, 16 times. + // + a = rotateLeft(a + H(b, c, d) + X[ 0] + 0x6ed9eba1, S31); + d = rotateLeft(d + H(a, b, c) + X[ 8] + 0x6ed9eba1, S32); + c = rotateLeft(c + H(d, a, b) + X[ 4] + 0x6ed9eba1, S33); + b = rotateLeft(b + H(c, d, a) + X[12] + 0x6ed9eba1, S34); + a = rotateLeft(a + H(b, c, d) + X[ 2] + 0x6ed9eba1, S31); + d = rotateLeft(d + H(a, b, c) + X[10] + 0x6ed9eba1, S32); + c = rotateLeft(c + H(d, a, b) + X[ 6] + 0x6ed9eba1, S33); + b = rotateLeft(b + H(c, d, a) + X[14] + 0x6ed9eba1, S34); + a = rotateLeft(a + H(b, c, d) + X[ 1] + 0x6ed9eba1, S31); + d = rotateLeft(d + H(a, b, c) + X[ 9] + 0x6ed9eba1, S32); + c = rotateLeft(c + H(d, a, b) + X[ 5] + 0x6ed9eba1, S33); + b = rotateLeft(b + H(c, d, a) + X[13] + 0x6ed9eba1, S34); + a = rotateLeft(a + H(b, c, d) + X[ 3] + 0x6ed9eba1, S31); + d = rotateLeft(d + H(a, b, c) + X[11] + 0x6ed9eba1, S32); + c = rotateLeft(c + H(d, a, b) + X[ 7] + 0x6ed9eba1, S33); + b = rotateLeft(b + H(c, d, a) + X[15] + 0x6ed9eba1, S34); + + H1 += a; + H2 += b; + H3 += c; + H4 += d; + + // + // reset the offset and clean out the word buffer. + // + xOff = 0; + for (int i = 0; i != X.length; i++) + { + X[i] = 0; + } + } + + public Memoable copy() + { + return new MD4Digest(this); + } + + public void reset(Memoable other) + { + MD4Digest d = (MD4Digest)other; + + copyIn(d); + } +} |