1 package org.bouncycastle.asn1.x9; 2 3 import org.bouncycastle.math.ec.ECCurve; 4 import org.bouncycastle.math.ec.ECFieldElement; 5 6 import java.math.BigInteger; 7 8 public class X9IntegerConverter 9 { 10 public int getByteLength( 11 ECCurve c) 12 { 13 return (c.getFieldSize() + 7) / 8; 14 } 15 16 public int getByteLength( 17 ECFieldElement fe) 18 { 19 return (fe.getFieldSize() + 7) / 8; 20 } 21 22 public byte[] integerToBytes( 23 BigInteger s, 24 int qLength) 25 { 26 byte[] bytes = s.toByteArray(); 27 28 if (qLength < bytes.length) 29 { 30 byte[] tmp = new byte[qLength]; 31 32 System.arraycopy(bytes, bytes.length - tmp.length, tmp, 0, tmp.length); 33 34 return tmp; 35 } 36 else if (qLength > bytes.length) 37 { 38 byte[] tmp = new byte[qLength]; 39 40 System.arraycopy(bytes, 0, tmp, tmp.length - bytes.length, bytes.length); 41 42 return tmp; 43 } 44 45 return bytes; 46 } 47 } 48
