本地证书实现数字信封加解密demo-java

package server; // // Source code recreated from a .class file by IntelliJ IDEA // (powered by Fernflower decompiler) // import java.io.ByteArrayOutputStream; import java.io.FileInputStream; import java.io.FileOutputStream; import java.math.BigInteger; public class Util { private static final char[] DIGITS_LOWER = new char[]{'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'}; private static final char[] DIGITS_UPPER = new char[]{'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'}; public Util() { } public static byte[] intToBytes(int num) { byte[] bytes = new byte[]{(byte)(255 & num >> 0), (byte)(255 & num >> 8), (byte)(255 & num >> 16), (byte)(255 & num >> 24)}; return bytes; } public static int byteToInt(byte[] bytes) { int num = 0; int temp = (255 & bytes[0]) << 0; num = num | temp; temp = (255 & bytes[1]) << 8; num |= temp; temp = (255 & bytes[2]) << 16; num |= temp; temp = (255 & bytes[3]) << 24; num |= temp; return num; } public static byte[] longToBytes(long num) { byte[] bytes = new byte[8]; for(int i = 0; i < 8; ++i) { bytes[i] = (byte)((int)(255L & num >> i * 8)); } return bytes; } public static byte[] byteConvert32Bytes(BigInteger n) { byte[] tmpd = (byte[])null; if (n == null) { return null; } else { if (n.toByteArray().length == 33) { tmpd = new byte[32]; System.arraycopy(n.toByteArray(), 1, tmpd, 0, 32); } else if (n.toByteArray().length == 32) { tmpd = n.toByteArray(); } else { tmpd = new byte[32]; for(int i = 0; i < 32 - n.toByteArray().length; ++i) { tmpd[i] = 0; } System.arraycopy(n.toByteArray(), 0, tmpd, 32 - n.toByteArray().length, n.toByteArray().length); } return tmpd; } } public static BigInteger byteConvertInteger(byte[] b) { if (b[0] < 0) { byte[] temp = new byte[b.length + 1]; temp[0] = 0; System.arraycopy(b, 0, temp, 1, b.length); return new BigInteger(temp); } else { return new BigInteger(b); } } public static String getHexString(byte[] bytes) { return getHexString(bytes, true); } public static String getHexString(byte[] bytes, boolean upperCase) { String ret = ""; for(int i = 0; i < bytes.length; ++i) { ret = ret + Integer.toString((bytes[i] & 255) + 256, 16).substring(1); } return upperCase ? ret.toUpperCase() : ret; } public static void printHexString(byte[] bytes) { for(int i = 0; i < bytes.length; ++i) { String hex = Integer.toHexString(bytes[i] & 255); if (hex.length() == 1) { hex = '0' + hex; } System.out.print("0x" + hex.toUpperCase() + ","); } System.out.println(""); } public static String bytesToHexString(byte[] src){ StringBuilder stringBuilder = new StringBuilder(""); if (src == null || src.length <= 0) { return null; } for (int i = 0; i < src.length; i++) { int v = src[i] & 0xFF; String hv = Integer.toHexString(v); if (hv.length() < 2) { stringBuilder.append(0); } stringBuilder.append(hv); } return stringBuilder.toString(); } public static byte[] hexStringToBytes(String hexString) { if (hexString != null && !hexString.equals("")) { hexString = hexString.toUpperCase(); int length = hexString.length() / 2; char[] hexChars = hexString.toCharArray(); byte[] d = new byte[length]; for(int i = 0; i < length; ++i) { int pos = i * 2; d[i] = (byte)(charToByte(hexChars[pos]) << 4 | charToByte(hexChars[pos + 1])); } return d; } else { return null; } } public static byte charToByte(char c) { return (byte)"0123456789ABCDEF".indexOf(c); } public static char[] encodeHex(byte[] data) { return encodeHex(data, true); } public static char[] encodeHex(byte[] data, boolean toLowerCase) { return encodeHex(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER); } protected static char[] encodeHex(byte[] data, char[] toDigits) { int l = data.length; char[] out = new char[l << 1]; int i = 0; for(int var5 = 0; i < l; ++i) { out[var5++] = toDigits[(240 & data[i]) >>> 4]; out[var5++] = toDigits[15 & data[i]]; } return out; } public static String encodeHexString(byte[] data) { return encodeHexString(data, true); } public static String encodeHexString(byte[] data, boolean toLowerCase) { return encodeHexString(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER); } protected static String encodeHexString(byte[] data, char[] toDigits) { return new String(encodeHex(data, toDigits)); } public static byte[] decodeHex(char[] data) { int len = data.length; if ((len & 1) != 0) { throw new RuntimeException("Odd number of characters."); } else { byte[] out = new byte[len >> 1]; int i = 0; for(int j = 0; j < len; ++i) { int f = toDigit(data[j], j) << 4; ++j; f |= toDigit(data[j], j); ++j; out[i] = (byte)(f & 255); } return out; } } protected static int toDigit(char ch, int index) { int digit = Character.digit(ch, 16); if (digit == -1) { throw new RuntimeException("Illegal hexadecimal character " + ch + " at index " + index); } else { return digit; } } public static String StringToAsciiString(String content) { String result = ""; int max = content.length(); for(int i = 0; i < max; ++i) { char c = content.charAt(i); String b = Integer.toHexString(c); result = result + b; } return result; } public static String hexStringToString(String hexString, int encodeType) { String result = ""; int max = hexString.length() / encodeType; for(int i = 0; i < max; ++i) { char c = (char)hexStringToAlgorism(hexString.substring(i * encodeType, (i + 1) * encodeType)); result = result + c; } return result; } public static int hexStringToAlgorism(String hex) { hex = hex.toUpperCase(); int max = hex.length(); int result = 0; for(int i = max; i > 0; --i) { char c = hex.charAt(i - 1); //int algorism = false; int algorism; if (c >= '0' && c <= '9') { algorism = c - 48; } else { algorism = c - 55; } result = (int)((double)result + Math.pow(16.0D, (double)(max - i)) * (double)algorism); } return result; } public static String hexStringToBinary(String hex) { hex = hex.toUpperCase(); String result = ""; int max = hex.length(); for(int i = 0; i < max; ++i) { char c = hex.ch