Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

[release/6.0] Fix HTTTP/2 header decoder buffer allocation #85341

Closed
wants to merge 1 commit into from
Closed
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Original file line number Diff line number Diff line change
Expand Up @@ -187,12 +187,11 @@ private void DecodeInternal(ReadOnlySpan<byte> data, IHttpHeadersHandler handler
// will no longer be valid.
if (_headerNameRange != null)
{
EnsureStringCapacity(ref _headerNameOctets);
EnsureStringCapacity(ref _headerNameOctets, _headerNameLength);
_headerName = _headerNameOctets;

ReadOnlySpan<byte> headerBytes = data.Slice(_headerNameRange.GetValueOrDefault().start, _headerNameRange.GetValueOrDefault().length);
headerBytes.CopyTo(_headerName);
_headerNameLength = headerBytes.Length;
_headerNameRange = null;
}
}
Expand Down Expand Up @@ -427,6 +426,7 @@ private void ParseHeaderName(ReadOnlySpan<byte> data, ref int currentIndex, IHtt
{
// Fast path. Store the range rather than copying.
_headerNameRange = (start: currentIndex, count);
_headerNameLength = _stringLength;
currentIndex += count;

_state = State.HeaderValueLength;
Expand Down Expand Up @@ -616,11 +616,12 @@ int Decode(ref byte[] dst)
_state = nextState;
}

private void EnsureStringCapacity(ref byte[] dst)
private void EnsureStringCapacity(ref byte[] dst, int stringLength = -1)
{
if (dst.Length < _stringLength)
stringLength = stringLength >= 0 ? stringLength : _stringLength;
if (dst.Length < stringLength)
{
dst = new byte[Math.Max(_stringLength, dst.Length * 2)];
dst = new byte[Math.Max(stringLength, dst.Length * 2)];
}
}

Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -46,8 +46,13 @@ public class HPackDecoderTests

private const string _headerNameString = "new-header";

// On purpose longer than 4096 (DefaultStringOctetsSize from HPackDecoder) to trigger https://github.com/dotnet/runtime/issues/78516
private static readonly string _literalHeaderNameString = string.Concat(Enumerable.Range(0, 4100).Select(c => (char)('a' + (c % 26))));

private static readonly byte[] _headerNameBytes = Encoding.ASCII.GetBytes(_headerNameString);

private static readonly byte[] _literalHeaderNameBytes = Encoding.ASCII.GetBytes(_literalHeaderNameString);

// n e w - h e a d e r *
// 10101000 10111110 00010110 10011100 10100011 10010000 10110110 01111111
private static readonly byte[] _headerNameHuffmanBytes = new byte[] { 0xa8, 0xbe, 0x16, 0x9c, 0xa3, 0x90, 0xb6, 0x7f };
Expand All @@ -64,6 +69,12 @@ public class HPackDecoderTests
.Concat(_headerNameBytes)
.ToArray();

// size = 4096 ==> 0x7f, 0x81, 0x1f (7+) prefixed integer
// size = 4100 ==> 0x7f, 0x85, 0x1f (7+) prefixed integer
private static readonly byte[] _literalHeaderName = new byte[] { 0x7f, 0x85, 0x1f } // 4100
.Concat(_literalHeaderNameBytes)
.ToArray();

private static readonly byte[] _headerNameHuffman = new byte[] { (byte)(0x80 | _headerNameHuffmanBytes.Length) }
.Concat(_headerNameHuffmanBytes)
.ToArray();
Expand Down Expand Up @@ -392,6 +403,101 @@ public void DecodesLiteralHeaderFieldNeverIndexed_IndexedName_OutOfRange_Error()
Assert.Empty(_handler.DecodedHeaders);
}

[Fact]
public void DecodesLiteralHeaderFieldNeverIndexed_NewName_SingleBuffer()
{
byte[] encoded = _literalHeaderFieldWithoutIndexingNewName
.Concat(_literalHeaderName)
.Concat(_headerValue)
.ToArray();

_decoder.Decode(encoded, endHeaders: true, handler: _handler);

Assert.Equal(1, _handler.DecodedHeaders.Count);
Assert.True(_handler.DecodedHeaders.ContainsKey(_literalHeaderNameString));
Assert.Equal(_headerValueString, _handler.DecodedHeaders[_literalHeaderNameString]);
}

[Fact]
public void DecodesLiteralHeaderFieldNeverIndexed_NewName_NameLengthBrokenIntoSeparateBuffers()
{
byte[] encoded = _literalHeaderFieldWithoutIndexingNewName
.Concat(_literalHeaderName)
.Concat(_headerValue)
.ToArray();

_decoder.Decode(encoded[..1], endHeaders: false, handler: _handler);
_decoder.Decode(encoded[1..], endHeaders: true, handler: _handler);

Assert.Equal(1, _handler.DecodedHeaders.Count);
Assert.True(_handler.DecodedHeaders.ContainsKey(_literalHeaderNameString));
Assert.Equal(_headerValueString, _handler.DecodedHeaders[_literalHeaderNameString]);
}

[Fact]
public void DecodesLiteralHeaderFieldNeverIndexed_NewName_NameBrokenIntoSeparateBuffers()
{
byte[] encoded = _literalHeaderFieldWithoutIndexingNewName
.Concat(_literalHeaderName)
.Concat(_headerValue)
.ToArray();

_decoder.Decode(encoded[..(_literalHeaderNameString.Length / 2)], endHeaders: false, handler: _handler);
_decoder.Decode(encoded[(_literalHeaderNameString.Length / 2)..], endHeaders: true, handler: _handler);

Assert.Equal(1, _handler.DecodedHeaders.Count);
Assert.True(_handler.DecodedHeaders.ContainsKey(_literalHeaderNameString));
Assert.Equal(_headerValueString, _handler.DecodedHeaders[_literalHeaderNameString]);
}

[Fact]
public void DecodesLiteralHeaderFieldNeverIndexed_NewName_NameAndValueBrokenIntoSeparateBuffers()
{
byte[] encoded = _literalHeaderFieldWithoutIndexingNewName
.Concat(_literalHeaderName)
.Concat(_headerValue)
.ToArray();

_decoder.Decode(encoded[..^_headerValue.Length], endHeaders: false, handler: _handler);
_decoder.Decode(encoded[^_headerValue.Length..], endHeaders: true, handler: _handler);

Assert.Equal(1, _handler.DecodedHeaders.Count);
Assert.True(_handler.DecodedHeaders.ContainsKey(_literalHeaderNameString));
Assert.Equal(_headerValueString, _handler.DecodedHeaders[_literalHeaderNameString]);
}

[Fact]
public void DecodesLiteralHeaderFieldNeverIndexed_NewName_ValueLengthBrokenIntoSeparateBuffers()
{
byte[] encoded = _literalHeaderFieldWithoutIndexingNewName
.Concat(_literalHeaderName)
.Concat(_headerValue)
.ToArray();

_decoder.Decode(encoded[..^(_headerValue.Length - 1)], endHeaders: false, handler: _handler);
_decoder.Decode(encoded[^(_headerValue.Length - 1)..], endHeaders: true, handler: _handler);

Assert.Equal(1, _handler.DecodedHeaders.Count);
Assert.True(_handler.DecodedHeaders.ContainsKey(_literalHeaderNameString));
Assert.Equal(_headerValueString, _handler.DecodedHeaders[_literalHeaderNameString]);
}

[Fact]
public void DecodesLiteralHeaderFieldNeverIndexed_NewName_ValueBrokenIntoSeparateBuffers()
{
byte[] encoded = _literalHeaderFieldWithoutIndexingNewName
.Concat(_literalHeaderName)
.Concat(_headerValue)
.ToArray();

_decoder.Decode(encoded[..^(_headerValueString.Length / 2)], endHeaders: false, handler: _handler);
_decoder.Decode(encoded[^(_headerValueString.Length / 2)..], endHeaders: true, handler: _handler);

Assert.Equal(1, _handler.DecodedHeaders.Count);
Assert.True(_handler.DecodedHeaders.ContainsKey(_literalHeaderNameString));
Assert.Equal(_headerValueString, _handler.DecodedHeaders[_literalHeaderNameString]);
}

[Fact]
public void DecodesDynamicTableSizeUpdate()
{
Expand Down