SigUtil | Javadocs [I2P+]

java.lang.Object

net.i2p.crypto.SigUtil

public final class SigUtilextends Object

Comprehensive utility class for I2P signing keys and digital signatures.

This class provides essential methods for converting between I2P's native key formats and standard Java cryptographic key representations, as well as utilities for signature encoding/decoding and key validation.

Key functionalities include:

Conversion between I2P and Java key formats
Support for DSA, ECDSA, EdDSA, and RSA algorithms
ASN.1 signature encoding and decoding
Key validation and rectification

Method Summary
All Methods
Modifier and Type
Method
Description
static NativeBigInteger[]
aSN1ToBigInteger(byte[] asn, int len)
See above.
static void
clearCaches()
Clear all cached Java key conversions.
(package private) static byte[]
combine(BigInteger x, BigInteger y, int len)
Combine two BigIntegers of nominal length = len / 2.
static SigningPrivateKey
fromJavaKey(DSAPrivateKey pk)
Convert a Java DSAPrivateKey to an I2P DSA private key.
static SigningPublicKey
fromJavaKey(DSAPublicKey pk)
Convert a Java DSAPublicKey to an I2P DSA public key.
static SigningPrivateKey
fromJavaKey(ECPrivateKey pk, SigType type)
Convert a Java ECPrivateKey to an I2P SigningPrivateKey of the given type.
static SigningPublicKey
fromJavaKey(ECPublicKey pk, SigType type)
Convert a Java ECPublicKey to an I2P SigningPublicKey of the given type.
static SigningPrivateKey
fromJavaKey(RSAPrivateKey pk, SigType type)
Convert a Java RSAPrivateKey to an I2P RSA private key of the given type.
static SigningPublicKey
fromJavaKey(RSAPublicKey pk, SigType type)
Convert a Java RSAPublicKey to an I2P RSA public key of the given type.
static SigningPrivateKey
fromJavaKey(PrivateKey pk)
Use if SigType is unknown.
static SigningPrivateKey
fromJavaKey(PrivateKey pk, SigType type)
Use if SigType is known.
static SigningPublicKey
fromJavaKey(PublicKey pk)
Use if SigType is unknown.
static SigningPublicKey
fromJavaKey(PublicKey pk, SigType type)
Use if SigType is known.
static SigningPrivateKey
fromJavaKey(EdDSAPrivateKey pk, SigType type)
Convert a Java EdDSAPrivateKey to an I2P SigningPrivateKey.
static SigningPublicKey
fromJavaKey(EdDSAPublicKey pk, SigType type)
Convert a Java EdDSAPublicKey to an I2P SigningPublicKey.
static Signature
fromJavaSig(byte[] asn, SigType type)
Convert a Java ASN.1 signature byte array to an I2P Signature.
static PrivateKey
importJavaPrivateKey(File file, SigType type)
Import a Java PKCS8-encoded private key from a file.
static PublicKey
importJavaPublicKey(File file, SigType type)
Import a Java X.509-encoded public key from a file.
static int
intToASN1(byte[] d, int idx, int val)
Output an length or integer value in ASN.1 Does NOT output the tag e.g.
static byte[]
rectify(BigInteger bi, int len)
Convert a BigInteger to a fixed-length byte array, trimming or zero-padding as needed.
static byte[]
sigBytesToASN1(BigInteger r, BigInteger s)
Encode two BigInteger values (r, s) into an ASN.1 DER SEQUENCE of two INTEGER values.
static DSAPrivateKey
toJavaDSAKey(SigningPrivateKey pk)
Convert an I2P DSA private key to a Java DSAPrivateKey.
static DSAPublicKey
toJavaDSAKey(SigningPublicKey pk)
Convert an I2P DSA public key to a Java DSAPublicKey.
static ECPrivateKey
toJavaECKey(SigningPrivateKey pk)
Convert an I2P EC private key to a Java ECPrivateKey, with caching.
static ECPublicKey
toJavaECKey(SigningPublicKey pk)
Convert an I2P EC public key to a Java ECPublicKey, with caching.
static EdDSAPrivateKey
toJavaEdDSAKey(SigningPrivateKey pk)
Convert an I2P EdDSA private key to a Java EdDSAPrivateKey, with caching.
static EdDSAPublicKey
toJavaEdDSAKey(SigningPublicKey pk)
Convert an I2P EdDSA public key to a Java EdDSAPublicKey, with caching.
static PrivateKey
toJavaKey(SigningPrivateKey pk)
Convert an I2P SigningPrivateKey to a Java PrivateKey, dispatching by algorithm.
static PublicKey
toJavaKey(SigningPublicKey pk)
Convert an I2P SigningPublicKey to a Java PublicKey, dispatching by algorithm.
static RSAPrivateKey
toJavaRSAKey(SigningPrivateKey pk)
Convert an I2P RSA private key to a Java RSAPrivateKey.
static RSAPublicKey
toJavaRSAKey(SigningPublicKey pk)
Prefer toJavaKey(SigningPublicKey) for type-generic conversion.
static byte[]
toJavaSig(Signature sig)
Convert an I2P Signature to a Java ASN.1 signature byte array.
Methods inherited from class Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details
- toJavaKey
  public static PublicKey toJavaKey(SigningPublicKey pk) throws GeneralSecurityException
  Convert an I2P SigningPublicKey to a Java PublicKey, dispatching by algorithm.
  Parameters:
  pk - non-null
  Returns:
  Java PublicKey (DSA, EC, EdDSA, or RSA)
  Throws:
  GeneralSecurityException - if conversion fails
- toJavaKey
  public static PrivateKey toJavaKey(SigningPrivateKey pk) throws GeneralSecurityException
  Convert an I2P SigningPrivateKey to a Java PrivateKey, dispatching by algorithm.
  Parameters:
  pk - non-null
  Returns:
  Java PrivateKey (DSA, EC, EdDSA, or RSA)
  Throws:
  GeneralSecurityException - if conversion fails
- fromJavaKey
  public static SigningPublicKey fromJavaKey(PublicKey pk) throws GeneralSecurityException
  Use if SigType is unknown. For efficiency, use fromJavakey(pk, type) if type is known.
  Parameters:
  pk - JAVA key!
  Returns:
  the I2P signing public key
  Throws:
  InvalidKeyException - on unknown type
  GeneralSecurityException
- fromJavaKey
  public static SigningPublicKey fromJavaKey(PublicKey pk, SigType type) throws GeneralSecurityException
  Use if SigType is known.
  Parameters:
  pk - JAVA key!
  type - the I2P signature type naming the base algorithm to convert with
  Returns:
  I2P public key
  Throws:
  GeneralSecurityException - if the JAVA key does not match the base algorithm of the type, or the type names an unknown algorithm
- fromJavaKey
  public static SigningPrivateKey fromJavaKey(PrivateKey pk) throws GeneralSecurityException
  Use if SigType is unknown. For efficiency, use fromJavakey(pk, type) if type is known.
  Parameters:
  pk - JAVA key!
  Returns:
  the I2P signing private key
  Throws:
  InvalidKeyException - on unknown type
  GeneralSecurityException
- fromJavaKey
  public static SigningPrivateKey fromJavaKey(PrivateKey pk, SigType type) throws GeneralSecurityException
  Use if SigType is known.
  Parameters:
  pk - JAVA key!
  type - the I2P signature type naming the base algorithm to convert with
  Returns:
  I2P private key
  Throws:
  GeneralSecurityException - if the JAVA key does not match the base algorithm of the type, or the type names an unknown algorithm
- toJavaECKey
  public static ECPublicKey toJavaECKey(SigningPublicKey pk) throws GeneralSecurityException
  Convert an I2P EC public key to a Java ECPublicKey, with caching.
  Parameters:
  pk - non-null
  Returns:
  Java ECPublicKey
  Throws:
  GeneralSecurityException - if conversion fails
- toJavaECKey
  public static ECPrivateKey toJavaECKey(SigningPrivateKey pk) throws GeneralSecurityException
  Convert an I2P EC private key to a Java ECPrivateKey, with caching.
  Parameters:
  pk - non-null
  Returns:
  Java ECPrivateKey
  Throws:
  GeneralSecurityException - if conversion fails
- fromJavaKey
  public static SigningPublicKey fromJavaKey(ECPublicKey pk, SigType type) throws GeneralSecurityException
  Convert a Java ECPublicKey to an I2P SigningPublicKey of the given type.
  Parameters:
  pk - non-null
  type - the I2P signature type
  Returns:
  I2P public key
  Throws:
  GeneralSecurityException - if conversion fails
- fromJavaKey
  public static SigningPrivateKey fromJavaKey(ECPrivateKey pk, SigType type) throws GeneralSecurityException
  Convert a Java ECPrivateKey to an I2P SigningPrivateKey of the given type.
  Parameters:
  pk - non-null
  type - the I2P signature type
  Returns:
  I2P private key
  Throws:
  GeneralSecurityException - if conversion fails
- toJavaEdDSAKey
  public static EdDSAPublicKey toJavaEdDSAKey(SigningPublicKey pk) throws GeneralSecurityException
  Convert an I2P EdDSA public key to a Java EdDSAPublicKey, with caching.
  Parameters:
  pk - non-null
  Returns:
  Java EdDSAPublicKey
  Throws:
  GeneralSecurityException - if the I2P key bytes cannot be converted to a Java EdDSA key
- toJavaEdDSAKey
  public static EdDSAPrivateKey toJavaEdDSAKey(SigningPrivateKey pk) throws GeneralSecurityException
  Convert an I2P EdDSA private key to a Java EdDSAPrivateKey, with caching.
  Parameters:
  pk - non-null
  Returns:
  Java EdDSAPrivateKey
  Throws:
  GeneralSecurityException - if the I2P key bytes cannot be converted to a Java EdDSA key
- fromJavaKey
  public static SigningPublicKey fromJavaKey(EdDSAPublicKey pk, SigType type)
  Convert a Java EdDSAPublicKey to an I2P SigningPublicKey.
  Parameters:
  pk - non-null
  type - the I2P signature type
  Returns:
  I2P public key
- fromJavaKey
  public static SigningPrivateKey fromJavaKey(EdDSAPrivateKey pk, SigType type) throws GeneralSecurityException
  Convert a Java EdDSAPrivateKey to an I2P SigningPrivateKey. Handles EdDSA (seed-based) and RedDSA (private scalar) key types.
  Parameters:
  pk - non-null
  type - the I2P signature type
  Returns:
  I2P private key
  Throws:
  GeneralSecurityException - if the key type names neither an EdDSA seed nor a RedDSA private scalar
- toJavaDSAKey
  public static DSAPublicKey toJavaDSAKey(SigningPublicKey pk) throws GeneralSecurityException
  Convert an I2P DSA public key to a Java DSAPublicKey.
  Parameters:
  pk - non-null
  Returns:
  Java DSAPublicKey
  Throws:
  GeneralSecurityException - if conversion fails
- toJavaDSAKey
  public static DSAPrivateKey toJavaDSAKey(SigningPrivateKey pk) throws GeneralSecurityException
  Convert an I2P DSA private key to a Java DSAPrivateKey.
  Parameters:
  pk - non-null
  Returns:
  Java DSAPrivateKey
  Throws:
  GeneralSecurityException - if conversion fails
- fromJavaKey
  public static SigningPublicKey fromJavaKey(DSAPublicKey pk) throws GeneralSecurityException
  Convert a Java DSAPublicKey to an I2P DSA public key.
  Parameters:
  pk - non-null
  Returns:
  I2P DSA public key
  Throws:
  GeneralSecurityException - if conversion fails
- fromJavaKey
  public static SigningPrivateKey fromJavaKey(DSAPrivateKey pk) throws GeneralSecurityException
  Convert a Java DSAPrivateKey to an I2P DSA private key.
  Parameters:
  pk - non-null
  Returns:
  I2P DSA private key
  Throws:
  GeneralSecurityException - if conversion fails
- toJavaRSAKey
  public static RSAPublicKey toJavaRSAKey(SigningPublicKey pk) throws GeneralSecurityException
  Prefer toJavaKey(SigningPublicKey) for type-generic conversion.
  Parameters:
  pk - non-null
  Returns:
  Java RSA public key
  Throws:
  GeneralSecurityException - if conversion fails
- toJavaRSAKey
  public static RSAPrivateKey toJavaRSAKey(SigningPrivateKey pk) throws GeneralSecurityException
  Convert an I2P RSA private key to a Java RSAPrivateKey. As of 0.9.31, if pk is a RSASigningPrivateCrtKey, returns a RSAPrivateCrtKey.
  Parameters:
  pk - non-null
  Returns:
  Java RSAPrivateKey
  Throws:
  GeneralSecurityException - if conversion fails
- fromJavaKey
  public static SigningPublicKey fromJavaKey(RSAPublicKey pk, SigType type) throws GeneralSecurityException
  Convert a Java RSAPublicKey to an I2P RSA public key of the given type.
  Parameters:
  pk - non-null
  type - the I2P signature type
  Returns:
  I2P RSA public key
  Throws:
  GeneralSecurityException - if conversion fails
- fromJavaKey
  public static SigningPrivateKey fromJavaKey(RSAPrivateKey pk, SigType type) throws GeneralSecurityException
  Convert a Java RSAPrivateKey to an I2P RSA private key of the given type. As of 0.9.31, if pk is a RSAPrivateCrtKey, returns a RSASigningPrivateCrtKey.
  Parameters:
  pk - non-null
  type - the I2P signature type
  Returns:
  I2P RSA private key
  Throws:
  GeneralSecurityException - if conversion fails
- toJavaSig
  public static byte[] toJavaSig(Signature sig)
  Convert an I2P Signature to a Java ASN.1 signature byte array. RSA and EdDSA signatures are passed through unchanged.
  Parameters:
  sig - non-null
  Returns:
  ASN.1 DER-encoded signature bytes (or raw for RSA/EdDSA)
- fromJavaSig
  public static Signature fromJavaSig(byte[] asn, SigType type) throws SignatureException
  Convert a Java ASN.1 signature byte array to an I2P Signature. RSA and EdDSA signatures are passed through unchanged.
  Parameters:
  asn - ASN.1 DER-encoded signature bytes (or raw for RSA/EdDSA)
  type - the I2P signature type
  Returns:
  an I2P Signature with the given type
  Throws:
  SignatureException - if ASN.1 decoding fails
- importJavaPublicKey
  public static PublicKey importJavaPublicKey(File file, SigType type) throws GeneralSecurityException, IOException
  Import a Java X.509-encoded public key from a file.
  Parameters:
  file - non-null, containing X.509 encoded key data
  type - the I2P signature type
  Returns:
  Java PublicKey
  Throws:
  GeneralSecurityException - if key conversion fails
  IOException - if file reading fails
- importJavaPrivateKey
  public static PrivateKey importJavaPrivateKey(File file, SigType type) throws GeneralSecurityException, IOException
  Import a Java PKCS8-encoded private key from a file.
  Parameters:
  file - non-null, containing PKCS8 encoded key data
  type - the I2P signature type
  Returns:
  Java PrivateKey
  Throws:
  GeneralSecurityException - if key conversion fails
  IOException - if file reading fails
- combine
  static byte[] combine(BigInteger x, BigInteger y, int len) throws InvalidKeyException
  Combine two BigIntegers of nominal length = len / 2.
  Parameters:
  x - non-negative first value
  y - non-negative second value
  len - total output length (must be even)
  Returns:
  array of exactly len bytes
  Throws:
  InvalidKeyException - if length is odd or either value is too large
- rectify
  public static byte[] rectify(BigInteger bi, int len) throws InvalidKeyException
  Convert a BigInteger to a fixed-length byte array, trimming or zero-padding as needed.
  Parameters:
  bi - non-negative
  len - desired output length
  Returns:
  array of exactly len bytes
  Throws:
  InvalidKeyException - if the value is negative or too large to fit
- sigBytesToASN1
  public static byte[] sigBytesToASN1(BigInteger r, BigInteger s)
  Encode two BigInteger values (r, s) into an ASN.1 DER SEQUENCE of two INTEGER values. r and s are always non-negative.
  Only supports sigs up to about 65530 bytes. See code to fix BER encoding for this before you add a SigType with bigger signatures.
  The output is an ASN.1 DER SEQUENCE of two INTEGER values, r and s, in that order:
  SEQUENCE ::= { r INTEGER, s INTEGER } 30 -- tag indicating SEQUENCE xx - length in octets 02 -- tag indicating INTEGER xx - length in octets xxxxxx - value
  Parameters:
  r - non-negative
  s - non-negative
  Returns:
  ASN.1 DER-encoded SEQUENCE { r INTEGER, s INTEGER }
  Throws:
  IllegalArgumentException - if too big
  See Also:
  Java Cryptography Architecture Reference Guide
  Abstract Syntax Notation One
- intToASN1
  public static int intToASN1(byte[] d, int idx, int val)
  Output an length or integer value in ASN.1 Does NOT output the tag e.g. 0x02 / 0x30.
  Parameters:
  d - the destination buffer to write the ASN.1 form into
  idx - the offset in d to start writing at, advanced past what is written
  val - 0-65535
  Returns:
  the new index
- aSN1ToBigInteger
  public static NativeBigInteger[] aSN1ToBigInteger(byte[] asn, int len) throws SignatureException
  See above. Only supports sigs up to about 65530 bytes. See code to fix BER encoding for bigger than that.
  Parameters:
  asn - the ASN.1 encoded signature or public key to decode
  len - the nominal length of each BigInteger the encoding holds
  Returns:
  the R and S integers, each of len bytes
  Throws:
  SignatureException - if the encoding does not hold the two integers of the expected length
- clearCaches
  public static void clearCaches()
  Clear all cached Java key conversions. Should be called when key types or configurations change.

Method Summary

Methods inherited from class Object

Method Details

toJavaKey

toJavaKey

fromJavaKey

fromJavaKey

fromJavaKey

fromJavaKey

toJavaECKey

toJavaECKey

fromJavaKey

fromJavaKey

toJavaEdDSAKey

toJavaEdDSAKey

fromJavaKey

fromJavaKey

toJavaDSAKey

toJavaDSAKey

fromJavaKey

fromJavaKey

toJavaRSAKey

toJavaRSAKey

fromJavaKey

fromJavaKey

toJavaSig

fromJavaSig

importJavaPublicKey

importJavaPrivateKey

combine

rectify

sigBytesToASN1

intToASN1

aSN1ToBigInteger

clearCaches