private void Append(ref KeyValueAccumulator accumulator)
{
if (ReadSucceded())
{
accumulator.Append(_currentKey, _currentValue);
if (accumulator.ValueCount > ValueCountLimit)
{
throw new InvalidDataException($"Form value count limit {ValueCountLimit} exceeded.");
}
}
}
private async Task<IFormCollection> InnerReadFormAsync(CancellationToken cancellationToken)
{
if (!HasFormContentType)
{
throw new InvalidOperationException("Incorrect Content-Type: " + _request.ContentType);
}
cancellationToken.ThrowIfCancellationRequested();
if (_options.BufferBody)
{
_request.EnableRewind(_options.MemoryBufferThreshold, _options.BufferBodyLengthLimit);
}
FormCollection formFields = null;
FormFileCollection files = null;
// Some of these code paths use StreamReader which does not support cancellation tokens.
using (cancellationToken.Register((state) => ((HttpContext)state).Abort(), _request.HttpContext))
{
var contentType = ContentType;
// Check the content-type
if (HasApplicationFormContentType(contentType))
{
var encoding = FilterEncoding(contentType.Encoding);
using (var formReader = new FormReader(_request.Body, encoding)
{
ValueCountLimit = _options.ValueCountLimit,
KeyLengthLimit = _options.KeyLengthLimit,
ValueLengthLimit = _options.ValueLengthLimit,
})
{
formFields = new FormCollection(await formReader.ReadFormAsync(cancellationToken));
}
}
else if (HasMultipartFormContentType(contentType))
{
var formAccumulator = new KeyValueAccumulator();
var boundary = GetBoundary(contentType, _options.MultipartBoundaryLengthLimit);
var multipartReader = new MultipartReader(boundary, _request.Body)
{
HeadersCountLimit = _options.MultipartHeadersCountLimit,
HeadersLengthLimit = _options.MultipartHeadersLengthLimit,
BodyLengthLimit = _options.MultipartBodyLengthLimit,
};
var section = await multipartReader.ReadNextSectionAsync(cancellationToken);
while (section != null)
{
ContentDispositionHeaderValue contentDisposition;
ContentDispositionHeaderValue.TryParse(section.ContentDisposition, out contentDisposition);
if (HasFileContentDisposition(contentDisposition))
{
// Enable buffering for the file if not already done for the full body
section.EnableRewind(_request.HttpContext.Response.RegisterForDispose,
_options.MemoryBufferThreshold, _options.MultipartBodyLengthLimit);
// Find the end
await section.Body.DrainAsync(cancellationToken);
var name = HeaderUtilities.RemoveQuotes(contentDisposition.Name) ?? string.Empty;
var fileName = HeaderUtilities.RemoveQuotes(contentDisposition.FileName) ?? string.Empty;
FormFile file;
if (section.BaseStreamOffset.HasValue)
{
// Relative reference to buffered request body
file = new FormFile(_request.Body, section.BaseStreamOffset.Value, section.Body.Length, name, fileName);
}
else
{
// Individually buffered file body
file = new FormFile(section.Body, 0, section.Body.Length, name, fileName);
}
file.Headers = new HeaderDictionary(section.Headers);
if (files == null)
{
files = new FormFileCollection();
}
if (files.Count >= _options.ValueCountLimit)
{
throw new InvalidDataException($"Form value count limit {_options.ValueCountLimit} exceeded.");
}
files.Add(file);
}
else if (HasFormDataContentDisposition(contentDisposition))
{
// Content-Disposition: form-data; name="key"
//
// value
// Do not limit the key name length here because the mulipart headers length limit is already in effect.
var key = HeaderUtilities.RemoveQuotes(contentDisposition.Name);
MediaTypeHeaderValue mediaType;
MediaTypeHeaderValue.TryParse(section.ContentType, out mediaType);
var encoding = FilterEncoding(mediaType?.Encoding);
using (var reader = new StreamReader(section.Body, encoding, detectEncodingFromByteOrderMarks: true, bufferSize: 1024, leaveOpen: true))
{
// The value length limit is enforced by MultipartBodyLengthLimit
var value = await reader.ReadToEndAsync();
formAccumulator.Append(key, value);
if (formAccumulator.ValueCount > _options.ValueCountLimit)
{
throw new InvalidDataException($"Form value count limit {_options.ValueCountLimit} exceeded.");
}
}
}
else
{
System.Diagnostics.Debug.Assert(false, "Unrecognized content-disposition for this section: " + section.ContentDisposition);
}
section = await multipartReader.ReadNextSectionAsync(cancellationToken);
}
if (formAccumulator.HasValues)
{
formFields = new FormCollection(formAccumulator.GetResults(), files);
}
}
}
// Rewind so later readers don't have to.
if (_request.Body.CanSeek)
{
_request.Body.Seek(0, SeekOrigin.Begin);
}
if (formFields != null)
{
Form = formFields;
}
else if (files != null)
{
Form = new FormCollection(null, files);
}
else
{
Form = FormCollection.Empty;
}
return Form;
}