public static void Decode(ref AsnValueReader reader, ReadOnlyMemory <byte> rebind, out GeneralNameAsn decoded)
{
decoded = default;
Asn1Tag tag = reader.PeekTag();
AsnValueReader explicitReader;
ReadOnlySpan <byte> rebindSpan = rebind.Span;
int offset;
ReadOnlySpan <byte> tmpSpan;
if (tag.HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 0)))
{
Medikit.Security.Cryptography.Asn1.OtherNameAsn tmpOtherName;
Medikit.Security.Cryptography.Asn1.OtherNameAsn.Decode(ref reader, new Asn1Tag(TagClass.ContextSpecific, 0), rebind, out tmpOtherName);
decoded.OtherName = tmpOtherName;
}
else if (tag.HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 1)))
{
decoded.Rfc822Name = reader.ReadCharacterString(new Asn1Tag(TagClass.ContextSpecific, 1), UniversalTagNumber.IA5String);
}
else if (tag.HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 2)))
{
decoded.DnsName = reader.ReadCharacterString(new Asn1Tag(TagClass.ContextSpecific, 2), UniversalTagNumber.IA5String);
}
else if (tag.HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 3)))
{
tmpSpan = reader.ReadEncodedValue();
decoded.X400Address = rebindSpan.Overlaps(tmpSpan, out offset) ? rebind.Slice(offset, tmpSpan.Length) : tmpSpan.ToArray();
}
else if (tag.HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 4)))
{
explicitReader = reader.ReadSequence(new Asn1Tag(TagClass.ContextSpecific, 4));
tmpSpan = explicitReader.ReadEncodedValue();
decoded.DirectoryName = rebindSpan.Overlaps(tmpSpan, out offset) ? rebind.Slice(offset, tmpSpan.Length) : tmpSpan.ToArray();
explicitReader.ThrowIfNotEmpty();
}
else if (tag.HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 5)))
{
Medikit.Security.Cryptography.Asn1.EdiPartyNameAsn tmpEdiPartyName;
Medikit.Security.Cryptography.Asn1.EdiPartyNameAsn.Decode(ref reader, new Asn1Tag(TagClass.ContextSpecific, 5), rebind, out tmpEdiPartyName);
decoded.EdiPartyName = tmpEdiPartyName;
}
else if (tag.HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 6)))
{
decoded.Uri = reader.ReadCharacterString(new Asn1Tag(TagClass.ContextSpecific, 6), UniversalTagNumber.IA5String);
}
else if (tag.HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 7)))
{
if (reader.TryReadPrimitiveOctetStringBytes(new Asn1Tag(TagClass.ContextSpecific, 7), out tmpSpan))
{
decoded.IPAddress = rebindSpan.Overlaps(tmpSpan, out offset) ? rebind.Slice(offset, tmpSpan.Length) : tmpSpan.ToArray();
}
else
{
decoded.IPAddress = reader.ReadOctetString(new Asn1Tag(TagClass.ContextSpecific, 7));
}
}
else if (tag.HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 8)))
{
decoded.RegisteredId = reader.ReadObjectIdentifierAsString(new Asn1Tag(TagClass.ContextSpecific, 8));
}
else
{
throw new CryptographicException();
}
}
public void Encode(AsnWriter writer)
{
bool wroteValue = false;
if (OtherName.HasValue)
{
if (wroteValue)
{
throw new CryptographicException();
}
OtherName.Value.Encode(writer, new Asn1Tag(TagClass.ContextSpecific, 0));
wroteValue = true;
}
if (Rfc822Name != null)
{
if (wroteValue)
{
throw new CryptographicException();
}
writer.WriteCharacterString(new Asn1Tag(TagClass.ContextSpecific, 1), UniversalTagNumber.IA5String, Rfc822Name);
wroteValue = true;
}
if (DnsName != null)
{
if (wroteValue)
{
throw new CryptographicException();
}
writer.WriteCharacterString(new Asn1Tag(TagClass.ContextSpecific, 2), UniversalTagNumber.IA5String, DnsName);
wroteValue = true;
}
if (X400Address.HasValue)
{
if (wroteValue)
{
throw new CryptographicException();
}
// Validator for tag constraint for X400Address
{
if (!Asn1Tag.TryDecode(X400Address.Value.Span, out Asn1Tag validateTag, out _) ||
!validateTag.HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 3)))
{
throw new CryptographicException();
}
}
writer.WriteEncodedValue(X400Address.Value.Span);
wroteValue = true;
}
if (DirectoryName.HasValue)
{
if (wroteValue)
{
throw new CryptographicException();
}
writer.PushSequence(new Asn1Tag(TagClass.ContextSpecific, 4));
writer.WriteEncodedValue(DirectoryName.Value.Span);
writer.PopSequence(new Asn1Tag(TagClass.ContextSpecific, 4));
wroteValue = true;
}
if (EdiPartyName.HasValue)
{
if (wroteValue)
{
throw new CryptographicException();
}
EdiPartyName.Value.Encode(writer, new Asn1Tag(TagClass.ContextSpecific, 5));
wroteValue = true;
}
if (Uri != null)
{
if (wroteValue)
{
throw new CryptographicException();
}
writer.WriteCharacterString(new Asn1Tag(TagClass.ContextSpecific, 6), UniversalTagNumber.IA5String, Uri);
wroteValue = true;
}
if (IPAddress.HasValue)
{
if (wroteValue)
{
throw new CryptographicException();
}
writer.WriteOctetString(new Asn1Tag(TagClass.ContextSpecific, 7), IPAddress.Value.Span);
wroteValue = true;
}
if (RegisteredId != null)
{
if (wroteValue)
{
throw new CryptographicException();
}
writer.WriteObjectIdentifier(new Asn1Tag(TagClass.ContextSpecific, 8), RegisteredId);
wroteValue = true;
}
if (!wroteValue)
{
throw new CryptographicException();
}
}
/// <summary>
/// Write an Object Identifier with a specified tag.
/// </summary>
/// <param name="tag">The tag to write.</param>
/// <param name="oidValue">The object identifier to write.</param>
/// <exception cref="ArgumentException">
/// <paramref name="tag"/>.<see cref="Asn1Tag.TagClass"/> is
/// <see cref="TagClass.Universal"/>, but
/// <paramref name="tag"/>.<see cref="Asn1Tag.TagValue"/> is not correct for
/// the method
/// </exception>
/// <exception cref="CryptographicException">
/// <paramref name="oidValue"/> is not a valid dotted decimal
/// object identifier
/// </exception>
/// <exception cref="ObjectDisposedException">The writer has been Disposed.</exception>
public void WriteObjectIdentifier(Asn1Tag tag, ReadOnlySpan <char> oidValue)
{
CheckUniversalTag(tag, UniversalTagNumber.ObjectIdentifier);
WriteObjectIdentifierCore(tag.AsPrimitive(), oidValue);
}
// T-REC-X.690-201508 sec 8.19
private void WriteObjectIdentifierCore(Asn1Tag tag, ReadOnlySpan <char> oidValue)
{
CheckDisposed();
// T-REC-X.690-201508 sec 8.19.4
// The first character is in { 0, 1, 2 }, the second will be a '.', and a third (digit)
// will also exist.
if (oidValue.Length < 3)
{
throw new CryptographicException(SR.Argument_InvalidOidValue);
}
if (oidValue[1] != '.')
{
throw new CryptographicException(SR.Argument_InvalidOidValue);
}
// The worst case is "1.1.1.1.1", which takes 4 bytes (5 components, with the first two condensed)
// Longer numbers get smaller: "2.1.127" is only 2 bytes. (81d (0x51) and 127 (0x7F))
// So length / 2 should prevent any reallocations.
byte[] tmp = CryptoPool.Rent(oidValue.Length / 2);
int tmpOffset = 0;
try
{
int firstComponent = oidValue[0] switch
{
'0' => 0,
'1' => 1,
'2' => 2,
_ => throw new CryptographicException(SR.Argument_InvalidOidValue),
};
// The first two components are special:
// ITU X.690 8.19.4:
// The numerical value of the first subidentifier is derived from the values of the first two
// object identifier components in the object identifier value being encoded, using the formula:
// (X*40) + Y
// where X is the value of the first object identifier component and Y is the value of the
// second object identifier component.
// NOTE - This packing of the first two object identifier components recognizes that only
// three values are allocated from the root node, and at most 39 subsequent values from
// nodes reached by X = 0 and X = 1.
// skip firstComponent and the trailing .
ReadOnlySpan <char> remaining = oidValue.Slice(2);
BigInteger subIdentifier = ParseSubIdentifier(ref remaining);
subIdentifier += 40 * firstComponent;
int localLen = EncodeSubIdentifier(tmp.AsSpan(tmpOffset), ref subIdentifier);
tmpOffset += localLen;
while (!remaining.IsEmpty)
{
subIdentifier = ParseSubIdentifier(ref remaining);
localLen = EncodeSubIdentifier(tmp.AsSpan(tmpOffset), ref subIdentifier);
tmpOffset += localLen;
}
Debug.Assert(!tag.IsConstructed);
WriteTag(tag);
WriteLength(tmpOffset);
Buffer.BlockCopy(tmp, 0, _buffer, _offset, tmpOffset);
_offset += tmpOffset;
}
finally
{
CryptoPool.Return(tmp, tmpOffset);
}
}
internal void Encode(AsnWriter writer, Asn1Tag tag)
{
writer.PushSequence(tag);
// DEFAULT value handler for HashAlgorithm.
{
using (AsnWriter tmp = new AsnWriter(AsnEncodingRules.DER))
{
HashAlgorithm.Encode(tmp);
ReadOnlySpan <byte> encoded = tmp.EncodeAsSpan();
if (!encoded.SequenceEqual(DefaultHashAlgorithm))
{
writer.PushSequence(new Asn1Tag(TagClass.ContextSpecific, 0));
writer.WriteEncodedValue(encoded);
writer.PopSequence(new Asn1Tag(TagClass.ContextSpecific, 0));
}
}
}
// DEFAULT value handler for MaskGenAlgorithm.
{
using (AsnWriter tmp = new AsnWriter(AsnEncodingRules.DER))
{
MaskGenAlgorithm.Encode(tmp);
ReadOnlySpan <byte> encoded = tmp.EncodeAsSpan();
if (!encoded.SequenceEqual(DefaultMaskGenAlgorithm))
{
writer.PushSequence(new Asn1Tag(TagClass.ContextSpecific, 1));
writer.WriteEncodedValue(encoded);
writer.PopSequence(new Asn1Tag(TagClass.ContextSpecific, 1));
}
}
}
// DEFAULT value handler for SaltLength.
{
using (AsnWriter tmp = new AsnWriter(AsnEncodingRules.DER))
{
tmp.WriteInteger(SaltLength);
ReadOnlySpan <byte> encoded = tmp.EncodeAsSpan();
if (!encoded.SequenceEqual(DefaultSaltLength))
{
writer.PushSequence(new Asn1Tag(TagClass.ContextSpecific, 2));
writer.WriteEncodedValue(encoded);
writer.PopSequence(new Asn1Tag(TagClass.ContextSpecific, 2));
}
}
}
// DEFAULT value handler for TrailerField.
{
using (AsnWriter tmp = new AsnWriter(AsnEncodingRules.DER))
{
tmp.WriteInteger(TrailerField);
ReadOnlySpan <byte> encoded = tmp.EncodeAsSpan();
if (!encoded.SequenceEqual(DefaultTrailerField))
{
writer.PushSequence(new Asn1Tag(TagClass.ContextSpecific, 3));
writer.WriteEncodedValue(encoded);
writer.PopSequence(new Asn1Tag(TagClass.ContextSpecific, 3));
}
}
}
writer.PopSequence(tag);
}
/// <summary>
/// Reads the next value as an Enumerated with tag UNIVERSAL 10, converting it to the
/// non-[<see cref="FlagsAttribute"/>] enum specfied by <typeparamref name="TEnum"/>.
/// </summary>
/// <param name="expectedTag">The tag to check for before reading.</param>
/// <typeparam name="TEnum">Destination enum type</typeparam>
/// <returns>
/// the Enumerated value converted to a <typeparamref name="TEnum"/>.
/// </returns>
/// <remarks>
/// This method does not validate that the return value is defined within
/// <typeparamref name="TEnum"/>.
/// </remarks>
/// <exception cref="CryptographicException">
/// the next value does not have the correct tag --OR--
/// the length encoding is not valid under the current encoding rules --OR--
/// the contents are not valid under the current encoding rules --OR--
/// the encoded value is too big to fit in a <typeparamref name="TEnum"/> value
/// </exception>
/// <exception cref="ArgumentException">
/// <typeparamref name="TEnum"/> is not an enum type --OR--
/// <typeparamref name="TEnum"/> was declared with <see cref="FlagsAttribute"/>
/// --OR--
/// <paramref name="expectedTag"/>.<see cref="Asn1Tag.TagClass"/> is
/// <see cref="TagClass.Universal"/>, but
/// <paramref name="expectedTag"/>.<see cref="Asn1Tag.TagValue"/> is not correct for
/// the method
/// </exception>
public TEnum ReadEnumeratedValue <TEnum>(Asn1Tag expectedTag) where TEnum : struct
{
Type tEnum = typeof(TEnum);
return((TEnum)Enum.ToObject(tEnum, ReadEnumeratedValue(expectedTag, tEnum)));
}
/// <summary>
/// Write an Integer value with a specified tag.
/// </summary>
/// <param name="tag">The tag to write.</param>
/// <param name="value">The value to write.</param>
/// <exception cref="ArgumentException">
/// <paramref name="tag"/>.<see cref="Asn1Tag.TagClass"/> is
/// <see cref="TagClass.Universal"/>, but
/// <paramref name="tag"/>.<see cref="Asn1Tag.TagValue"/> is not correct for
/// the method
/// </exception>
/// <exception cref="ObjectDisposedException">The writer has been Disposed.</exception>
public void WriteInteger(Asn1Tag tag, ulong value)
{
CheckUniversalTag(tag, UniversalTagNumber.Integer);
WriteNonNegativeIntegerCore(tag.AsPrimitive(), value);
}
internal static void Decode(ref AsnValueReader reader, Asn1Tag expectedTag, ReadOnlyMemory <byte> rebind, out PssParamsAsn decoded)
{
decoded = default;
AsnValueReader sequenceReader = reader.ReadSequence(expectedTag);
AsnValueReader explicitReader;
AsnValueReader defaultReader;
if (sequenceReader.HasData && sequenceReader.PeekTag().HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 0)))
{
explicitReader = sequenceReader.ReadSequence(new Asn1Tag(TagClass.ContextSpecific, 0));
Medikit.Security.Cryptography.Asn1.AlgorithmIdentifierAsn.Decode(ref explicitReader, rebind, out decoded.HashAlgorithm);
explicitReader.ThrowIfNotEmpty();
}
else
{
defaultReader = new AsnValueReader(DefaultHashAlgorithm, AsnEncodingRules.DER);
Medikit.Security.Cryptography.Asn1.AlgorithmIdentifierAsn.Decode(ref defaultReader, rebind, out decoded.HashAlgorithm);
}
if (sequenceReader.HasData && sequenceReader.PeekTag().HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 1)))
{
explicitReader = sequenceReader.ReadSequence(new Asn1Tag(TagClass.ContextSpecific, 1));
Medikit.Security.Cryptography.Asn1.AlgorithmIdentifierAsn.Decode(ref explicitReader, rebind, out decoded.MaskGenAlgorithm);
explicitReader.ThrowIfNotEmpty();
}
else
{
defaultReader = new AsnValueReader(DefaultMaskGenAlgorithm, AsnEncodingRules.DER);
Medikit.Security.Cryptography.Asn1.AlgorithmIdentifierAsn.Decode(ref defaultReader, rebind, out decoded.MaskGenAlgorithm);
}
if (sequenceReader.HasData && sequenceReader.PeekTag().HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 2)))
{
explicitReader = sequenceReader.ReadSequence(new Asn1Tag(TagClass.ContextSpecific, 2));
if (!explicitReader.TryReadInt32(out decoded.SaltLength))
{
explicitReader.ThrowIfNotEmpty();
}
explicitReader.ThrowIfNotEmpty();
}
else
{
defaultReader = new AsnValueReader(DefaultSaltLength, AsnEncodingRules.DER);
if (!defaultReader.TryReadInt32(out decoded.SaltLength))
{
defaultReader.ThrowIfNotEmpty();
}
}
if (sequenceReader.HasData && sequenceReader.PeekTag().HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 3)))
{
explicitReader = sequenceReader.ReadSequence(new Asn1Tag(TagClass.ContextSpecific, 3));
if (!explicitReader.TryReadInt32(out decoded.TrailerField))
{
explicitReader.ThrowIfNotEmpty();
}
explicitReader.ThrowIfNotEmpty();
}
else
{
defaultReader = new AsnValueReader(DefaultTrailerField, AsnEncodingRules.DER);
if (!defaultReader.TryReadInt32(out decoded.TrailerField))
{
defaultReader.ThrowIfNotEmpty();
}
}
sequenceReader.ThrowIfNotEmpty();
}
// T-REC-X.690-201508 sec 8.3
private void WriteNonNegativeIntegerCore(Asn1Tag tag, ulong value)
{
int valueLength;
// 0x80 needs two bytes: 0x00 0x80
if (value < 0x80)
{
valueLength = 1;
}
else if (value < 0x8000)
{
valueLength = 2;
}
else if (value < 0x800000)
{
valueLength = 3;
}
else if (value < 0x80000000)
{
valueLength = 4;
}
else if (value < 0x80_00000000)
{
valueLength = 5;
}
else if (value < 0x8000_00000000)
{
valueLength = 6;
}
else if (value < 0x800000_00000000)
{
valueLength = 7;
}
else if (value < 0x80000000_00000000)
{
valueLength = 8;
}
else
{
valueLength = 9;
}
// Clear the constructed bit, if it was set.
Debug.Assert(!tag.IsConstructed);
WriteTag(tag);
WriteLength(valueLength);
ulong remaining = value;
int idx = _offset + valueLength - 1;
do
{
_buffer[idx] = (byte)remaining;
remaining >>= 8;
idx--;
} while (idx >= _offset);
#if DEBUG
if (valueLength > 1)
{
// T-REC-X.690-201508 sec 8.3.2
// Cannot start with 9 bits of 0 (or 9 bits of 1, but that's not this method).
Debug.Assert(_buffer[_offset] != 0 || _buffer[_offset + 1] > 0x7F);
}
#endif
_offset += valueLength;
}
// T-REC-X.690-201508 sec 8.3
private void WriteIntegerCore(Asn1Tag tag, long value)
{
if (value >= 0)
{
WriteNonNegativeIntegerCore(tag, (ulong)value);
return;
}
int valueLength;
if (value >= sbyte.MinValue)
{
valueLength = 1;
}
else if (value >= short.MinValue)
{
valueLength = 2;
}
else if (value >= unchecked ((long)0xFFFFFFFF_FF800000))
{
valueLength = 3;
}
else if (value >= int.MinValue)
{
valueLength = 4;
}
else if (value >= unchecked ((long)0xFFFFFF80_00000000))
{
valueLength = 5;
}
else if (value >= unchecked ((long)0xFFFF8000_00000000))
{
valueLength = 6;
}
else if (value >= unchecked ((long)0xFF800000_00000000))
{
valueLength = 7;
}
else
{
valueLength = 8;
}
Debug.Assert(!tag.IsConstructed);
WriteTag(tag);
WriteLength(valueLength);
long remaining = value;
int idx = _offset + valueLength - 1;
do
{
_buffer[idx] = (byte)remaining;
remaining >>= 8;
idx--;
} while (idx >= _offset);
#if DEBUG
if (valueLength > 1)
{
// T-REC-X.690-201508 sec 8.3.2
// Cannot start with 9 bits of 1 (or 9 bits of 0, but that's not this method).
Debug.Assert(_buffer[_offset] != 0xFF || _buffer[_offset + 1] < 0x80);
}
#endif
_offset += valueLength;
}
/// <summary>
/// Write an Integer value with a specified tag.
/// </summary>
/// <param name="tag">The tag to write.</param>
/// <param name="value">The integer value to write, in unsigned big-endian byte order.</param>
/// <exception cref="ArgumentException">
/// <paramref name="tag"/>.<see cref="Asn1Tag.TagClass"/> is
/// <see cref="TagClass.Universal"/>, but
/// <paramref name="tag"/>.<see cref="Asn1Tag.TagValue"/> is not correct for
/// the method
/// </exception>
/// <exception cref="CryptographicException">
/// the 9 most sigificant bits are all unset
/// </exception>
/// <exception cref="ObjectDisposedException">The writer has been Disposed.</exception>
public void WriteIntegerUnsigned(Asn1Tag tag, ReadOnlySpan <byte> value)
{
CheckUniversalTag(tag, UniversalTagNumber.Integer);
WriteIntegerUnsignedCore(tag.AsPrimitive(), value);
}
/// <summary>
/// Write an Integer value with a specified tag.
/// </summary>
/// <param name="tag">The tag to write.</param>
/// <param name="value">The value to write.</param>
/// <exception cref="ArgumentException">
/// <paramref name="tag"/>.<see cref="Asn1Tag.TagClass"/> is
/// <see cref="TagClass.Universal"/>, but
/// <paramref name="tag"/>.<see cref="Asn1Tag.TagValue"/> is not correct for
/// the method
/// </exception>
/// <exception cref="ObjectDisposedException">The writer has been Disposed.</exception>
public void WriteInteger(Asn1Tag tag, BigInteger value)
{
CheckUniversalTag(tag, UniversalTagNumber.Integer);
WriteIntegerCore(tag.AsPrimitive(), value);
}
/// <summary>
/// Write a Boolean value with a specified tag.
/// </summary>
/// <param name="tag">The tag to write.</param>
/// <param name="value">The value to write.</param>
/// <exception cref="ArgumentException">
/// <paramref name="tag"/>.<see cref="Asn1Tag.TagClass"/> is
/// <see cref="TagClass.Universal"/>, but
/// <paramref name="tag"/>.<see cref="Asn1Tag.TagValue"/> is not correct for
/// the method
/// </exception>
public void WriteBoolean(Asn1Tag tag, bool value)
{
CheckUniversalTag(tag, UniversalTagNumber.Boolean);
WriteBooleanCore(tag.AsPrimitive(), value);
}
