public static void ReadIntegers()
{
byte[] derEncoded =
{
/* SEQUENCE */ 0x30, 23,
/* INTEGER(0) */ 0x02, 0x01, 0x00,
/* INTEGER(256) */ 0x02, 0x02, 0x01, 0x00,
/* INTEGER(-1) */ 0x02, 0x01, 0xFF,
/* Big integer */ 0x02, 0x0B, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D,
};
DerSequenceReader reader = new DerSequenceReader(derEncoded);
Assert.True(reader.HasData);
Assert.Equal(23, reader.ContentLength);
int first = reader.ReadInteger();
Assert.Equal(0, first);
int second = reader.ReadInteger();
Assert.Equal(256, second);
int third = reader.ReadInteger();
Assert.Equal(-1, third);
// Reader reads Big-Endian, BigInteger reads Little-Endian
byte[] fourthBytes = reader.ReadIntegerBytes();
Array.Reverse(fourthBytes);
BigInteger fourth = new BigInteger(fourthBytes);
Assert.Equal(BigInteger.Parse("3645759592820458633497613"), fourth);
// And... done.
Assert.False(reader.HasData);
}
/// <summary>
/// Convert Der format of (r, s) to Ieee1363 format
/// </summary>
public static byte[] ConvertDerToIeee1363(byte[] input, int inputOffset, int inputCount, int fieldSizeBits)
{
int size = BitsToBytes(fieldSizeBits);
try
{
DerSequenceReader reader = new DerSequenceReader(input, inputOffset, inputCount);
byte[] rDer = reader.ReadIntegerBytes();
byte[] sDer = reader.ReadIntegerBytes();
byte[] response = new byte[2 * size];
CopySignatureField(rDer, response, 0, size);
CopySignatureField(sDer, response, size, size);
return(response);
}
catch (InvalidOperationException e)
{
throw new CryptographicException(SR.Arg_CryptographyException, e);
}
}
public static byte[] ConvertDerToIeee1363(byte[] input, int inputOffset, int inputCount, int fieldSizeBits)
{
int bytes = BitsToBytes(fieldSizeBits);
try
{
DerSequenceReader derSequenceReader =
new DerSequenceReader(input, inputOffset, inputCount);
byte[] signatureField1 = derSequenceReader.ReadIntegerBytes();
byte[] signatureField2 = derSequenceReader.ReadIntegerBytes();
byte[] response = new byte[2 * bytes];
CopySignatureField(signatureField1, response, 0, bytes);
CopySignatureField(signatureField2, response, bytes, bytes);
return(response);
}
catch (System.InvalidOperationException ex)
{
throw new System.Security.Cryptography.CryptographicException($"Cryptography Exception", ex);
}
}
internal static byte[] GetAsn1IntegerBytes(SafeSharedAsn1IntegerHandle asn1Integer)
{
CheckValidOpenSslHandle(asn1Integer);
// OpenSSL stores negative numbers in their two's complement (positive) form, but
// sets an internal negative bit.
//
// If the number was positive, but could sign-test as negative, DER puts in a leading
// 0x00 byte, which reading OpenSSL's data directly won't have.
//
// So to ensure we're getting a set of bytes compatible with BigInteger (though with the
// wrong endianness here), DER encode it, then use the DER reader to skip past the tag
// and length.
byte[] derEncoded = OpenSslEncode(
handle => GetAsn1IntegerDerSize(handle),
(handle, buf) => EncodeAsn1Integer(handle, buf),
asn1Integer);
DerSequenceReader reader = DerSequenceReader.CreateForPayload(derEncoded);
return(reader.ReadIntegerBytes());
}
public static void ReadIntegers()
{
byte[] derEncoded =
{
/* SEQUENCE */ 0x30, 23,
/* INTEGER(0) */ 0x02, 0x01, 0x00,
/* INTEGER(256) */ 0x02, 0x02, 0x01, 0x00,
/* INTEGER(-1) */ 0x02, 0x01, 0xFF,
/* Big integer */ 0x02, 0x0B, 0x03, 0x04,0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D,
};
DerSequenceReader reader = new DerSequenceReader(derEncoded);
Assert.True(reader.HasData);
Assert.Equal(23, reader.ContentLength);
int first = reader.ReadInteger();
Assert.Equal(0, first);
int second = reader.ReadInteger();
Assert.Equal(256, second);
int third = reader.ReadInteger();
Assert.Equal(-1, third);
// Reader reads Big-Endian, BigInteger reads Little-Endian
byte[] fourthBytes = reader.ReadIntegerBytes();
Array.Reverse(fourthBytes);
BigInteger fourth = new BigInteger(fourthBytes);
Assert.Equal(BigInteger.Parse("3645759592820458633497613"), fourth);
// And... done.
Assert.False(reader.HasData);
}