/// <inheritdoc/>
public bool TryGetHeader(JwtHeader header, KeyManagementAlgorithm alg, EncryptionAlgorithm enc, JsonEncodedText kid, string?typ, string?cty, [NotNullWhen(true)] out byte[]?base64UrlHeader)
{
if (ReferenceEquals(_firstHeader.Header, header))
{
base64UrlHeader = _firstHeader.BinaryHeader;
goto Found;
}
if (IsEligibleHeaderForJwe(header.Count, kid, typ, cty))
{
int algorithmId = enc.ComputeKey(alg);
var node = _head;
while (node != null)
{
if (algorithmId == node.AlgorithmId)
{
if (node.TryGetEntry(kid, out var entry))
{
if (cty != entry.Cty)
{
goto NotFound;
}
if (typ != entry.Typ)
{
goto NotFound;
}
base64UrlHeader = entry.Data;
if (node != _head)
{
MoveToHead(node);
}
goto Found;
}
}
node = node.Next;
}
}
NotFound:
#if NET5_0_OR_GREATER
Unsafe.SkipInit(out base64UrlHeader);
#else
base64UrlHeader = default;
#endif
return(false);
Found:
return(true);
}
/// <inheritdoc/>
public void AddHeader(JwtHeader header, KeyManagementAlgorithm alg, EncryptionAlgorithm enc, JsonEncodedText kid, string?typ, string?cty, ReadOnlySpan <byte> base6UrlHeader)
{
_firstHeader = new WrappedHeader(header, base6UrlHeader.ToArray());
if (IsEligibleHeaderForJwe(header.Count, kid, typ, cty))
{
int algorithmId = enc.ComputeKey(alg);
bool lockTaken = false;
try
{
_spinLock.Enter(ref lockTaken);
if (_count >= MaxSize)
{
_head = null;
_tail = null;
_count = 0;
}
var node = _head;
while (node != null)
{
if (algorithmId == node.AlgorithmId)
{
break;
}
node = node.Next;
}
var key = alg.Id;
if (node is null)
{
_count++;
node = new Bucket(algorithmId, kid, new CacheEntry(base6UrlHeader.ToArray(), typ, cty))
{
Next = _head
};
}
else
{
if (!node.Entries.ContainsKey(kid !))
{
_count++;
node.Entries[kid] = new CacheEntry(base6UrlHeader.ToArray(), typ, cty);
}
}
if (!ReferenceEquals(_head, node))
{
if (_head != null)
{
_head.Previous = node;
}
_head = node;
}
if (_tail is null)
{
_tail = node;
}
}
finally
{
if (lockTaken)
{
_spinLock.Exit();
}
}
}
}
