DerInteger
using Org.BouncyCastle.Math;
using Org.BouncyCastle.Utilities;
using System;
using System.IO;
namespace Org.BouncyCastle.Asn1
{
public class DerInteger : Asn1Object
{
internal class Meta : Asn1UniversalType
{
internal static readonly Asn1UniversalType Instance = new Meta();
private Meta()
: base(typeof(DerInteger), 2)
{
}
internal override Asn1Object FromImplicitPrimitive(DerOctetString octetString)
{
return CreatePrimitive(octetString.GetOctets());
}
}
public const string AllowUnsafeProperty = "Org.BouncyCastle.Asn1.AllowUnsafeInteger";
internal const int SignExtSigned = -1;
internal const int SignExtUnsigned = 255;
private readonly byte[] bytes;
private readonly int start;
public BigInteger PositiveValue => new BigInteger(1, bytes);
public BigInteger Value => new BigInteger(bytes);
public int IntPositiveValueExact {
get {
int num = bytes.Length - start;
if (num > 4 || (num == 4 && (bytes[start] & 128) != 0))
throw new ArithmeticException("ASN.1 Integer out of positive int range");
return IntValue(bytes, start, 255);
}
}
public int IntValueExact {
get {
if (bytes.Length - start > 4)
throw new ArithmeticException("ASN.1 Integer out of int range");
return IntValue(bytes, start, -1);
}
}
public long LongValueExact {
get {
if (bytes.Length - start > 8)
throw new ArithmeticException("ASN.1 Integer out of long range");
return LongValue(bytes, start, -1);
}
}
internal static bool AllowUnsafe()
{
string environmentVariable = Platform.GetEnvironmentVariable("Org.BouncyCastle.Asn1.AllowUnsafeInteger");
if (environmentVariable != null)
return Platform.EqualsIgnoreCase("true", environmentVariable);
return false;
}
public static DerInteger GetInstance(object obj)
{
if (obj == null)
return null;
DerInteger derInteger = obj as DerInteger;
if (derInteger != null)
return derInteger;
IAsn1Convertible asn1Convertible = obj as IAsn1Convertible;
if (asn1Convertible != null) {
DerInteger derInteger2 = asn1Convertible.ToAsn1Object() as DerInteger;
if (derInteger2 != null)
return derInteger2;
} else {
byte[] array = obj as byte[];
if (array != null)
try {
return (DerInteger)Meta.Instance.FromByteArray(array);
} catch (IOException ex) {
throw new ArgumentException("failed to construct integer from byte[]: " + ex.Message);
}
}
throw new ArgumentException("illegal object in GetInstance: " + Platform.GetTypeName(obj));
}
public static DerInteger GetInstance(Asn1TaggedObject taggedObject, bool declaredExplicit)
{
return (DerInteger)Meta.Instance.GetContextInstance(taggedObject, declaredExplicit);
}
public DerInteger(int value)
{
bytes = BigInteger.ValueOf(value).ToByteArray();
start = 0;
}
public DerInteger(long value)
{
bytes = BigInteger.ValueOf(value).ToByteArray();
start = 0;
}
public DerInteger(BigInteger value)
{
if (value == null)
throw new ArgumentNullException("value");
bytes = value.ToByteArray();
start = 0;
}
public DerInteger(byte[] bytes)
: this(bytes, true)
{
}
internal DerInteger(byte[] bytes, bool clone)
{
if (IsMalformed(bytes))
throw new ArgumentException("malformed integer", "bytes");
this.bytes = (clone ? Arrays.Clone(bytes) : bytes);
start = SignBytesToSkip(bytes);
}
public bool HasValue(int x)
{
if (bytes.Length - start <= 4)
return IntValue(bytes, start, -1) == x;
return false;
}
public bool HasValue(long x)
{
if (bytes.Length - start <= 8)
return LongValue(bytes, start, -1) == x;
return false;
}
public bool HasValue(BigInteger x)
{
if (x != null && IntValue(bytes, start, -1) == x.IntValue)
return Value.Equals(x);
return false;
}
internal override IAsn1Encoding GetEncoding(int encoding)
{
return new PrimitiveEncoding(0, 2, bytes);
}
internal override IAsn1Encoding GetEncodingImplicit(int encoding, int tagClass, int tagNo)
{
return new PrimitiveEncoding(tagClass, tagNo, bytes);
}
internal sealed override DerEncoding GetEncodingDer()
{
return new PrimitiveDerEncoding(0, 2, bytes);
}
internal sealed override DerEncoding GetEncodingDerImplicit(int tagClass, int tagNo)
{
return new PrimitiveDerEncoding(tagClass, tagNo, bytes);
}
protected override int Asn1GetHashCode()
{
return Arrays.GetHashCode(bytes);
}
protected override bool Asn1Equals(Asn1Object asn1Object)
{
DerInteger derInteger = asn1Object as DerInteger;
if (derInteger == null)
return false;
return Arrays.AreEqual(bytes, derInteger.bytes);
}
public override string ToString()
{
return Value.ToString();
}
internal static DerInteger CreatePrimitive(byte[] contents)
{
return new DerInteger(contents, false);
}
internal static int GetEncodingLength(BigInteger x)
{
return Asn1OutputStream.GetLengthOfEncodingDL(2, BigIntegers.GetByteLength(x));
}
internal static int IntValue(byte[] bytes, int start, int signExt)
{
int num = bytes.Length;
int num2 = System.Math.Max(start, num - 4);
int num3 = (sbyte)bytes[num2] & signExt;
while (++num2 < num) {
num3 = ((num3 << 8) | bytes[num2]);
}
return num3;
}
internal static long LongValue(byte[] bytes, int start, int signExt)
{
int num = bytes.Length;
int num2 = System.Math.Max(start, num - 8);
long num3 = (sbyte)bytes[num2] & signExt;
while (++num2 < num) {
num3 = ((num3 << 8) | bytes[num2]);
}
return num3;
}
internal static bool IsMalformed(byte[] bytes)
{
switch (bytes.LongLength) {
case 0:
return true;
case 1:
return false;
default:
if ((sbyte)bytes[0] == (sbyte)bytes[1] >> 7)
return !AllowUnsafe();
return false;
}
}
internal static int SignBytesToSkip(byte[] bytes)
{
int i = 0;
for (int num = bytes.Length - 1; i < num && (sbyte)bytes[i] == (sbyte)bytes[i + 1] >> 7; i++) {
}
return i;
}
}
}