Module com.hedera.hashgraph.sdk
Package com.hedera.hashgraph.sdk

Class Crypto

java.lang.Object
com.hedera.hashgraph.sdk.Crypto
final class Crypto extends Object
Utility class used internally by the sdk.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    (package private) static final int
    CBC_DK_LEN
     
    (package private) static final int
    DK_LEN
     
    (package private) static final org.bouncycastle.asn1.x9.X9ECParameters
    ECDSA_SECP256K1_CURVE
     
    (package private) static final org.bouncycastle.crypto.params.ECDomainParameters
    ECDSA_SECP256K1_DOMAIN
     
    (package private) static final int
    ITERATIONS
     
    (package private) static final int
    IV_LEN
     
    (package private) static final int
    SALT_LEN
     

  • Method Summary

    Modifier and Type
    Method
    Description
    (package private) static byte[]
    calcHmacSha384(org.bouncycastle.crypto.params.KeyParameter cipherKey, byte[] iv, byte[] input)
    Calculate a hash message authentication code using the secure hash algorithm variant 384.
    (package private) static byte[]
    calcKeccak256(byte[] message)
    Calculate a keccak 256-bit hash.
    (package private) static byte[]
    decryptAesCtr128(org.bouncycastle.crypto.params.KeyParameter cipherKey, byte[] iv, byte[] input)
    Decrypt a byte array with the aes ctr cipher.
    (package private) static org.bouncycastle.crypto.params.KeyParameter
    deriveKeySha256(String passphrase, byte[] salt, int iterations, int dkLenBytes)
    Derive a sha 256 key.
    (package private) static byte[]
    encryptAesCtr128(org.bouncycastle.crypto.params.KeyParameter cipherKey, byte[] iv, byte[] input)
    Encrypt a byte array with the aes ctr cipher.
    (package private) static Cipher
    initAesCbc128Decrypt(org.bouncycastle.crypto.params.KeyParameter cipherKey, AlgorithmParameters parameters)
    Initialize an advanced encryption standard cipher block chaining mode cipher for decryption.
    (package private) static Cipher
    initAesCbc128Encrypt(org.bouncycastle.crypto.params.KeyParameter cipherKey, byte[] iv)
    Initialize an advanced encryption standard cipher block chaining mode cipher for encryption.
    (package private) static Cipher
    initAesCtr128(org.bouncycastle.crypto.params.KeyParameter cipherKey, byte[] iv, boolean forDecrypt)
    Initialize an advanced encryption standard counter mode cipher.
    (package private) static byte[]
    randomBytes(int len)
    Generate some randomness.
    (package private) static byte[]
    recoverPublicKeyECDSAFromSignature(int recId, BigInteger r, BigInteger s, byte[] messageHash)
    Given the r and s components of a signature and the hash value of the message, recover and return the public key according to the algorithm in SEC1v2 section 4.1.6.
    (package private) static byte[]
    runCipher(Cipher cipher, byte[] input)
    Run the cipher on the given input.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • IV_LEN

      static final int IV_LEN
      See Also:

    • ITERATIONS

      static final int ITERATIONS
      See Also:

    • SALT_LEN

      static final int SALT_LEN
      See Also:

    • DK_LEN

      static final int DK_LEN
      See Also:

    • CBC_DK_LEN

      static final int CBC_DK_LEN
      See Also:

    • ECDSA_SECP256K1_CURVE

      static final org.bouncycastle.asn1.x9.X9ECParameters ECDSA_SECP256K1_CURVE

    • ECDSA_SECP256K1_DOMAIN

      static final org.bouncycastle.crypto.params.ECDomainParameters ECDSA_SECP256K1_DOMAIN

  • Method Details

    • deriveKeySha256

      static org.bouncycastle.crypto.params.KeyParameter deriveKeySha256(String passphrase, byte[] salt, int iterations, int dkLenBytes)
      Derive a sha 256 key.
      Parameters:
      passphrase - the password will be converted into bytes
      salt - the salt to be mixed in
      iterations - the iterations for mixing
      dkLenBytes - the key length in bytes
      Returns:
      the key parameter object

    • initAesCtr128

      static Cipher initAesCtr128(org.bouncycastle.crypto.params.KeyParameter cipherKey, byte[] iv, boolean forDecrypt)
      Initialize an advanced encryption standard counter mode cipher.
      Parameters:
      cipherKey - the cipher key
      iv - the initialization vector byte array
      forDecrypt - is this for decryption
      Returns:
      the aes ctr cipher

    • initAesCbc128Encrypt

      static Cipher initAesCbc128Encrypt(org.bouncycastle.crypto.params.KeyParameter cipherKey, byte[] iv)
      Initialize an advanced encryption standard cipher block chaining mode cipher for encryption.
      Parameters:
      cipherKey - the cipher key
      iv - the initialization vector byte array
      Returns:
      the aes cbc cipher

    • initAesCbc128Decrypt

      static Cipher initAesCbc128Decrypt(org.bouncycastle.crypto.params.KeyParameter cipherKey, AlgorithmParameters parameters)
      Initialize an advanced encryption standard cipher block chaining mode cipher for decryption.
      Parameters:
      cipherKey - the cipher key
      parameters - the algorithm parameters
      Returns:
      the aes cbc cipher

    • encryptAesCtr128

      static byte[] encryptAesCtr128(org.bouncycastle.crypto.params.KeyParameter cipherKey, byte[] iv, byte[] input)
      Encrypt a byte array with the aes ctr cipher.
      Parameters:
      cipherKey - the cipher key
      iv - the initialization vector
      input - the byte array to encrypt
      Returns:
      the encrypted byte array

    • decryptAesCtr128

      static byte[] decryptAesCtr128(org.bouncycastle.crypto.params.KeyParameter cipherKey, byte[] iv, byte[] input)
      Decrypt a byte array with the aes ctr cipher.
      Parameters:
      cipherKey - the cipher key
      iv - the initialization vector
      input - the byte array to decrypt
      Returns:
      the decrypted byte array

    • runCipher

      static byte[] runCipher(Cipher cipher, byte[] input)
      Run the cipher on the given input.
      Parameters:
      cipher - the cipher
      input - the byte array
      Returns:
      the output of running the cipher

    • calcHmacSha384

      static byte[] calcHmacSha384(org.bouncycastle.crypto.params.KeyParameter cipherKey, @Nullable byte[] iv, byte[] input)
      Calculate a hash message authentication code using the secure hash algorithm variant 384.
      Parameters:
      cipherKey - the cipher key
      iv - the initialization vector
      input - the byte array
      Returns:
      the hmac using sha 384

    • calcKeccak256

      static byte[] calcKeccak256(byte[] message)
      Calculate a keccak 256-bit hash.
      Parameters:
      message - the message to be hashed
      Returns:
      the hash

    • randomBytes

      static byte[] randomBytes(int len)
      Generate some randomness.
      Parameters:
      len - the number of bytes requested
      Returns:
      the byte array of randomness

    • recoverPublicKeyECDSAFromSignature

      static byte[] recoverPublicKeyECDSAFromSignature(int recId, BigInteger r, BigInteger s, byte[] messageHash)
      Given the r and s components of a signature and the hash value of the message, recover and return the public key according to the algorithm in SEC1v2 section 4.1.6.

      Calculations and explanations in this method were taken and adapted from incubator-tuweni lib

      Parameters:
      recId - Which possible key to recover.
      r - The R component of the signature.
      s - The S component of the signature.
      messageHash - Hash of the data that was signed.
      Returns:
      A ECKey containing only the public part, or null if recovery wasn't possible.