Examples with HKDFBytesGenerator org.bouncycastle.crypto.generators.HKDFBytesGenerator used on opensource projects

Example 1 with HKDFBytesGenerator

use of org.bouncycastle.crypto.generators.HKDFBytesGenerator in project habot by ghys.

the class HttpEce method hkdfExpand.

/**
 * Convenience method for computing the HMAC Key Derivation Function. The
 * real work is offloaded to BouncyCastle.
 */
protected static byte[] hkdfExpand(byte[] ikm, byte[] salt, byte[] info, int length) throws InvalidKeyException, NoSuchAlgorithmException {
    HKDFBytesGenerator hkdf = new HKDFBytesGenerator(new SHA256Digest());
    hkdf.init(new HKDFParameters(ikm, salt, info));
    byte[] okm = new byte[length];
    hkdf.generateBytes(okm, 0, length);
    return okm;
}

Example 2 with HKDFBytesGenerator

use of org.bouncycastle.crypto.generators.HKDFBytesGenerator in project nem2-sdk-java by nemtech.

the class Hashes method sha256ForSharedKey.

/**
 * Hasher used for shared keys
 *
 * @param sharedSecret the shared secret
 * @return the shared key hash.
 */
public static byte[] sha256ForSharedKey(byte[] sharedSecret) {
    Digest hash = new SHA256Digest();
    byte[] info = "catapult".getBytes();
    int length = 32;
    byte[] sharedKey = new byte[length];
    HKDFParameters params = new HKDFParameters(sharedSecret, null, info);
    HKDFBytesGenerator hkdf = new HKDFBytesGenerator(hash);
    hkdf.init(params);
    hkdf.generateBytes(sharedKey, 0, length);
    return sharedKey;
}

Example 3 with HKDFBytesGenerator

use of org.bouncycastle.crypto.generators.HKDFBytesGenerator in project syncany by syncany.

the class CipherUtil method createDerivedKey.

/**
 * Creates a derived key from the given input key material (raw byte array) and an input salt
 * and wraps the key in  a {@link SecretKeySpec} using the given output key algorithm and output
 * key size.
 *
 * <p>The algorithm used to derive the new key from the input key material (IKM) is the
 * <b>HMAC-based Extract-and-Expand Key Derivation Function (HKDF)</b> (see
 * <a href="http://tools.ietf.org/html/rfc5869">RFC 5869</a>)
 *
 * @param inputKeyMaterial The input key material as raw data bytes, e.g. determined from {@link SecretKey#getEncoded()}
 * @param inputSalt Input salt used to generate the new key (a non-secret random value!)
 * @param outputKeyAlgorithm Defines the algorithm of the new output key (for {@link SecretKeySpec#getAlgorithm()})
 * @param outputKeySize Defines the key size of the new output key
 * @return Returns a new pseudorandom key derived from the input key material using HKDF
 * @see <a href="http://tools.ietf.org/html/rfc5869">RFC 5869</a>
 */
public static SaltedSecretKey createDerivedKey(byte[] inputKeyMaterial, byte[] inputSalt, String outputKeyAlgorithm, int outputKeySize) throws InvalidKeySpecException, NoSuchAlgorithmException, NoSuchProviderException {
    HKDFBytesGenerator hkdf = new HKDFBytesGenerator(KEY_DERIVATION_DIGEST);
    hkdf.init(new HKDFParameters(inputKeyMaterial, inputSalt, KEY_DERIVATION_INFO));
    byte[] derivedKey = new byte[outputKeySize / 8];
    hkdf.generateBytes(derivedKey, 0, derivedKey.length);
    return toSaltedSecretKey(derivedKey, inputSalt, outputKeyAlgorithm);
}