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package org.bouncycastle.crypto.digests; /* The BLAKE2 cryptographic hash function was designed by Jean- Philippe Aumasson, Samuel Neves, Zooko Wilcox-O'Hearn, and Christian Winnerlein. Reference Implementation and Description can be found at: https://blake2.net/ Internet Draft: https://tools.ietf.org/html/draft-saarinen-blake2-02 This implementation does not support the Tree Hashing Mode. For unkeyed hashing, developers adapting BLAKE2 to ASN.1 - based message formats SHOULD use the OID tree at x = 1.3.6.1.4.1.1722.12.2. Algorithm | Target | Collision | Hash | Hash ASN.1 | Identifier | Arch | Security | nn | OID Suffix | ---------------+--------+-----------+------+------------+ id-blake2b160 | 64-bit | 2**80 | 20 | x.1.20 | id-blake2b256 | 64-bit | 2**128 | 32 | x.1.32 | id-blake2b384 | 64-bit | 2**192 | 48 | x.1.48 | id-blake2b512 | 64-bit | 2**256 | 64 | x.1.64 | ---------------+--------+-----------+------+------------+ */ import org.bouncycastle.crypto.ExtendedDigest; import org.bouncycastle.util.Arrays; import org.bouncycastle.util.Pack; /** * Implementation of the cryptographic hash function Blakbe2b. * <p> * Blake2b offers a built-in keying mechanism to be used directly * for authentication ("Prefix-MAC") rather than a HMAC construction. * <p> * Blake2b offers a built-in support for a salt for randomized hashing * and a personal string for defining a unique hash function for each application. * <p> * BLAKE2b is optimized for 64-bit platforms and produces digests of any size * between 1 and 64 bytes. */ public class Blake2bDigest implements ExtendedDigest { // Blake2b Initialization Vector: private final static long[] blake2b_IV = // Produced from the square root of primes 2, 3, 5, 7, 11, 13, 17, 19. // The same as SHA-512 IV. { 0x6a09e667f3bcc908L, 0xbb67ae8584caa73bL, 0x3c6ef372fe94f82bL, 0xa54ff53a5f1d36f1L, 0x510e527fade682d1L, 0x9b05688c2b3e6c1fL, 0x1f83d9abfb41bd6bL, 0x5be0cd19137e2179L }; // Message word permutations: private final static byte[][] blake2b_sigma = { { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }, { 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 }, { 11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4 }, { 7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8 }, { 9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13 }, { 2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9 }, { 12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11 }, { 13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10 }, { 6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5 }, { 10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0 }, { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }, { 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 } }; private static int ROUNDS = 12; // to use for Catenas H' private final static int BLOCK_LENGTH_BYTES = 128;// bytes // General parameters: private int digestLength = 64; // 1- 64 bytes private int keyLength = 0; // 0 - 64 bytes for keyed hashing for MAC private byte[] salt = null;// new byte[16]; private byte[] personalization = null;// new byte[16]; // the key private byte[] key = null; // Tree hashing parameters: // Because this class does not implement the Tree Hashing Mode, // these parameters can be treated as constants (see init() function) /* * private int fanout = 1; // 0-255 private int depth = 1; // 1 - 255 * private int leafLength= 0; private long nodeOffset = 0L; private int * nodeDepth = 0; private int innerHashLength = 0; */ // whenever this buffer overflows, it will be processed // in the compress() function. // For performance issues, long messages will not use this buffer. private byte[] buffer = null;// new byte[BLOCK_LENGTH_BYTES]; // Position of last inserted byte: private int bufferPos = 0;// a value from 0 up to 128 private long[] internalState = new long[16]; // In the Blake2b paper it is // called: v private long[] chainValue = null; // state vector, in the Blake2b paper it // is called: h private long t0 = 0L; // holds last significant bits, counter (counts bytes) private long t1 = 0L; // counter: Length up to 2^128 are supported private long f0 = 0L; // finalization flag, for last block: ~0L // For Tree Hashing Mode, not used here: // private long f1 = 0L; // finalization flag, for last node: ~0L public Blake2bDigest() { this(512); } public Blake2bDigest(Blake2bDigest digest) { this.bufferPos = digest.bufferPos; this.buffer = Arrays.clone(digest.buffer); this.keyLength = digest.keyLength; this.key = Arrays.clone(digest.key); this.digestLength = digest.digestLength; this.chainValue = Arrays.clone(digest.chainValue); this.personalization = Arrays.clone(digest.personalization); this.salt = Arrays.clone(digest.salt); this.t0 = digest.t0; this.t1 = digest.t1; this.f0 = digest.f0; } /** * Basic sized constructor - size in bits. * * @param digestSize size of the digest in bits */ public Blake2bDigest(int digestSize) { if (digestSize < 8 || digestSize > 512 || digestSize % 8 != 0) { throw new IllegalArgumentException( "BLAKE2b digest bit length must be a multiple of 8 and not greater than 512"); } buffer = new byte[BLOCK_LENGTH_BYTES]; keyLength = 0; this.digestLength = digestSize / 8; init(); } /** * Blake2b for authentication ("Prefix-MAC mode"). * After calling the doFinal() method, the key will * remain to be used for further computations of * this instance. * The key can be overwritten using the clearKey() method. * * @param key A key up to 64 bytes or null */ public Blake2bDigest(byte[] key) { buffer = new byte[BLOCK_LENGTH_BYTES]; if (key != null) { this.key = new byte[key.length]; System.arraycopy(key, 0, this.key, 0, key.length); if (key.length > 64) { throw new IllegalArgumentException("Keys > 64 are not supported"); } keyLength = key.length; System.arraycopy(key, 0, buffer, 0, key.length); bufferPos = BLOCK_LENGTH_BYTES; // zero padding } digestLength = 64; init(); } /** * Blake2b with key, required digest length (in bytes), salt and personalization. * After calling the doFinal() method, the key, the salt and the personal string * will remain and might be used for further computations with this instance. * The key can be overwritten using the clearKey() method, the salt (pepper) * can be overwritten using the clearSalt() method. * * @param key A key up to 64 bytes or null * @param digestLength from 1 up to 64 bytes * @param salt 16 bytes or null * @param personalization 16 bytes or null */ public Blake2bDigest(byte[] key, int digestLength, byte[] salt, byte[] personalization) { buffer = new byte[BLOCK_LENGTH_BYTES]; if (digestLength < 1 || digestLength > 64) { throw new IllegalArgumentException("Invalid digest length (required: 1 - 64)"); } this.digestLength = digestLength; if (salt != null) { if (salt.length != 16) { throw new IllegalArgumentException("salt length must be exactly 16 bytes"); } this.salt = new byte[16]; System.arraycopy(salt, 0, this.salt, 0, salt.length); } if (personalization != null) { if (personalization.length != 16) { throw new IllegalArgumentException("personalization length must be exactly 16 bytes"); } this.personalization = new byte[16]; System.arraycopy(personalization, 0, this.personalization, 0, personalization.length); } if (key != null) { this.key = new byte[key.length]; System.arraycopy(key, 0, this.key, 0, key.length); if (key.length > 64) { throw new IllegalArgumentException("Keys > 64 are not supported"); } keyLength = key.length; System.arraycopy(key, 0, buffer, 0, key.length); bufferPos = BLOCK_LENGTH_BYTES; // zero padding } init(); } // initialize chainValue private void init() { if (chainValue == null) { chainValue = new long[8]; chainValue[0] = blake2b_IV[0] ^ (digestLength | (keyLength << 8) | 0x1010000); // 0x1010000 = ((fanout << 16) | (depth << 24) | (leafLength << // 32)); // with fanout = 1; depth = 0; leafLength = 0; chainValue[1] = blake2b_IV[1];// ^ nodeOffset; with nodeOffset = 0; chainValue[2] = blake2b_IV[2];// ^ ( nodeDepth | (innerHashLength << // 8) ); // with nodeDepth = 0; innerHashLength = 0; chainValue[3] = blake2b_IV[3]; chainValue[4] = blake2b_IV[4]; chainValue[5] = blake2b_IV[5]; if (salt != null) { chainValue[4] ^= Pack.littleEndianToLong(salt, 0); chainValue[5] ^= Pack.littleEndianToLong(salt, 8); } chainValue[6] = blake2b_IV[6]; chainValue[7] = blake2b_IV[7]; if (personalization != null) { chainValue[6] ^= Pack.littleEndianToLong(personalization, 0); chainValue[7] ^= Pack.littleEndianToLong(personalization, 8); } } } private void initializeInternalState() { // initialize v: System.arraycopy(chainValue, 0, internalState, 0, chainValue.length); System.arraycopy(blake2b_IV, 0, internalState, chainValue.length, 4); internalState[12] = t0 ^ blake2b_IV[4]; internalState[13] = t1 ^ blake2b_IV[5]; internalState[14] = f0 ^ blake2b_IV[6]; internalState[15] = blake2b_IV[7];// ^ f1 with f1 = 0 } /** * update the message digest with a single byte. * * @param b the input byte to be entered. */ public void update(byte b) { int remainingLength = 0; // left bytes of buffer // process the buffer if full else add to buffer: remainingLength = BLOCK_LENGTH_BYTES - bufferPos; if (remainingLength == 0) { // full buffer t0 += BLOCK_LENGTH_BYTES; if (t0 == 0) { // if message > 2^64 t1++; } compress(buffer, 0); Arrays.fill(buffer, (byte) 0);// clear buffer buffer[0] = b; bufferPos = 1; } else { buffer[bufferPos] = b; bufferPos++; return; } } /** * update the message digest with a block of bytes. * * @param message the byte array containing the data. * @param offset the offset into the byte array where the data starts. * @param len the length of the data. */ public void update(byte[] message, int offset, int len) { if (message == null || len == 0) { return; } int remainingLength = 0; // left bytes of buffer if (bufferPos != 0) { // commenced, incomplete buffer // complete the buffer: remainingLength = BLOCK_LENGTH_BYTES - bufferPos; if (remainingLength < len) { // full buffer + at least 1 byte System.arraycopy(message, offset, buffer, bufferPos, remainingLength); t0 += BLOCK_LENGTH_BYTES; if (t0 == 0) { // if message > 2^64 t1++; } compress(buffer, 0); bufferPos = 0; Arrays.fill(buffer, (byte) 0);// clear buffer } else { System.arraycopy(message, offset, buffer, bufferPos, len); bufferPos += len; return; } } // process blocks except last block (also if last block is full) int messagePos; int blockWiseLastPos = offset + len - BLOCK_LENGTH_BYTES; for (messagePos = offset + remainingLength; messagePos < blockWiseLastPos; messagePos += BLOCK_LENGTH_BYTES) { // block wise 128 bytes // without buffer: t0 += BLOCK_LENGTH_BYTES; if (t0 == 0) { t1++; } compress(message, messagePos); } // fill the buffer with left bytes, this might be a full block System.arraycopy(message, messagePos, buffer, 0, offset + len - messagePos); bufferPos += offset + len - messagePos; } /** * close the digest, producing the final digest value. The doFinal * call leaves the digest reset. * Key, salt and personal string remain. * * @param out the array the digest is to be copied into. * @param outOffset the offset into the out array the digest is to start at. */ public int doFinal(byte[] out, int outOffset) { f0 = 0xFFFFFFFFFFFFFFFFL; t0 += bufferPos; if (bufferPos > 0 && t0 == 0) { t1++; } compress(buffer, 0); Arrays.fill(buffer, (byte) 0);// Holds eventually the key if input is null Arrays.fill(internalState, 0L); for (int i = 0; i < chainValue.length && (i * 8 < digestLength); i++) { byte[] bytes = Pack.longToLittleEndian(chainValue[i]); if (i * 8 < digestLength - 8) { System.arraycopy(bytes, 0, out, outOffset + i * 8, 8); } else { System.arraycopy(bytes, 0, out, outOffset + i * 8, digestLength - (i * 8)); } } Arrays.fill(chainValue, 0L); reset(); return digestLength; } /** * Reset the digest back to it's initial state. * The key, the salt and the personal string will * remain for further computations. */ public void reset() { bufferPos = 0; f0 = 0L; t0 = 0L; t1 = 0L; chainValue = null; Arrays.fill(buffer, (byte) 0); if (key != null) { System.arraycopy(key, 0, buffer, 0, key.length); bufferPos = BLOCK_LENGTH_BYTES; // zero padding } init(); } private void compress(byte[] message, int messagePos) { initializeInternalState(); long[] m = new long[16]; for (int j = 0; j < 16; j++) { m[j] = Pack.littleEndianToLong(message, messagePos + j * 8); } for (int round = 0; round < ROUNDS; round++) { // G apply to columns of internalState:m[blake2b_sigma[round][2 * // blockPos]] /+1 G(m[blake2b_sigma[round][0]], m[blake2b_sigma[round][1]], 0, 4, 8, 12); G(m[blake2b_sigma[round][2]], m[blake2b_sigma[round][3]], 1, 5, 9, 13); G(m[blake2b_sigma[round][4]], m[blake2b_sigma[round][5]], 2, 6, 10, 14); G(m[blake2b_sigma[round][6]], m[blake2b_sigma[round][7]], 3, 7, 11, 15); // G apply to diagonals of internalState: G(m[blake2b_sigma[round][8]], m[blake2b_sigma[round][9]], 0, 5, 10, 15); G(m[blake2b_sigma[round][10]], m[blake2b_sigma[round][11]], 1, 6, 11, 12); G(m[blake2b_sigma[round][12]], m[blake2b_sigma[round][13]], 2, 7, 8, 13); G(m[blake2b_sigma[round][14]], m[blake2b_sigma[round][15]], 3, 4, 9, 14); } // update chain values: for (int offset = 0; offset < chainValue.length; offset++) { chainValue[offset] = chainValue[offset] ^ internalState[offset] ^ internalState[offset + 8]; } } private void G(long m1, long m2, int posA, int posB, int posC, int posD) { internalState[posA] = internalState[posA] + internalState[posB] + m1; internalState[posD] = rotr64(internalState[posD] ^ internalState[posA], 32); internalState[posC] = internalState[posC] + internalState[posD]; internalState[posB] = rotr64(internalState[posB] ^ internalState[posC], 24); // replaces 25 of BLAKE internalState[posA] = internalState[posA] + internalState[posB] + m2; internalState[posD] = rotr64(internalState[posD] ^ internalState[posA], 16); internalState[posC] = internalState[posC] + internalState[posD]; internalState[posB] = rotr64(internalState[posB] ^ internalState[posC], 63); // replaces 11 of BLAKE } private static long rotr64(long x, int rot) { return x >>> rot | (x << (64 - rot)); } /** * return the algorithm name * * @return the algorithm name */ public String getAlgorithmName() { return "BLAKE2b"; } /** * return the size, in bytes, of the digest produced by this message digest. * * @return the size, in bytes, of the digest produced by this message digest. */ public int getDigestSize() { return digestLength; } /** * Return the size in bytes of the internal buffer the digest applies it's compression * function to. * * @return byte length of the digests internal buffer. */ public int getByteLength() { return BLOCK_LENGTH_BYTES; } /** * Overwrite the key * if it is no longer used (zeroization) */ public void clearKey() { if (key != null) { Arrays.fill(key, (byte) 0); Arrays.fill(buffer, (byte) 0); } } /** * Overwrite the salt (pepper) if it * is secret and no longer used (zeroization) */ public void clearSalt() { if (salt != null) { Arrays.fill(salt, (byte) 0); } } }