| package org.bouncycastle.crypto.util; |
| |
| public abstract class Pack |
| { |
| public static int bigEndianToInt(byte[] bs, int off) |
| { |
| int n = bs[ off] << 24; |
| n |= (bs[++off] & 0xff) << 16; |
| n |= (bs[++off] & 0xff) << 8; |
| n |= (bs[++off] & 0xff); |
| return n; |
| } |
| |
| public static void intToBigEndian(int n, byte[] bs, int off) |
| { |
| bs[ off] = (byte)(n >>> 24); |
| bs[++off] = (byte)(n >>> 16); |
| bs[++off] = (byte)(n >>> 8); |
| bs[++off] = (byte)(n ); |
| } |
| |
| public static long bigEndianToLong(byte[] bs, int off) |
| { |
| int hi = bigEndianToInt(bs, off); |
| int lo = bigEndianToInt(bs, off + 4); |
| return ((long)(hi & 0xffffffffL) << 32) | (long)(lo & 0xffffffffL); |
| } |
| |
| public static void longToBigEndian(long n, byte[] bs, int off) |
| { |
| intToBigEndian((int)(n >>> 32), bs, off); |
| intToBigEndian((int)(n & 0xffffffffL), bs, off + 4); |
| } |
| |
| public static int littleEndianToInt(byte[] bs, int off) |
| { |
| int n = bs[ off]; |
| n |= (bs[++off] & 0xff) << 8; |
| n |= (bs[++off] & 0xff) << 16; |
| n |= (bs[++off] & 0xff) << 24; |
| return n; |
| } |
| |
| public static void intToLittleEndian(int n, byte[] bs, int off) |
| { |
| bs[ off] = (byte)(n ); |
| bs[++off] = (byte)(n >>> 8); |
| bs[++off] = (byte)(n >>> 16); |
| bs[++off] = (byte)(n >>> 24); |
| } |
| |
| public static long littleEndianToLong(byte[] bs, int off) |
| { |
| int lo = littleEndianToInt(bs, off); |
| int hi = littleEndianToInt(bs, off + 4); |
| return ((long)(hi & 0xffffffffL) << 32) | (long)(lo & 0xffffffffL); |
| } |
| |
| public static void longToLittleEndian(long n, byte[] bs, int off) |
| { |
| intToLittleEndian((int)(n & 0xffffffffL), bs, off); |
| intToLittleEndian((int)(n >>> 32), bs, off + 4); |
| } |
| } |