| | 1 | | // Copyright (c) Microsoft Corporation. All rights reserved. |
| | 2 | | // Licensed under the MIT License. |
| | 3 | |
|
| | 4 | | // Copied from https://github.com/aspnet/AspNetCore/tree/master/src/Http/WebUtilities/src |
| | 5 | |
|
| | 6 | | using System; |
| | 7 | | using System.Collections.Generic; |
| | 8 | | using System.Diagnostics; |
| | 9 | | using System.IO; |
| | 10 | | using System.Threading; |
| | 11 | | using System.Threading.Tasks; |
| | 12 | |
|
| | 13 | | #pragma warning disable CA1001 // disposable fields |
| | 14 | | #pragma warning disable IDE0008 // Use explicit type |
| | 15 | |
|
| | 16 | | namespace Azure.Core.Http.Multipart |
| | 17 | | { |
| | 18 | | // https://www.ietf.org/rfc/rfc2046.txt |
| | 19 | | internal class MultipartReader |
| | 20 | | { |
| | 21 | | public const int DefaultHeadersCountLimit = 16; |
| | 22 | | public const int DefaultHeadersLengthLimit = 1024 * 16; |
| | 23 | | private const int DefaultBufferSize = 1024 * 4; |
| | 24 | |
|
| | 25 | | private readonly BufferedReadStream _stream; |
| | 26 | | private readonly MultipartBoundary _boundary; |
| | 27 | | private MultipartReaderStream _currentStream; |
| | 28 | |
|
| | 29 | | public MultipartReader(string boundary, Stream stream) |
| 88 | 30 | | : this(boundary, stream, DefaultBufferSize) |
| | 31 | | { |
| 88 | 32 | | } |
| | 33 | |
|
| 88 | 34 | | public MultipartReader(string boundary, Stream stream, int bufferSize) |
| | 35 | | { |
| 88 | 36 | | if (boundary == null) |
| | 37 | | { |
| 0 | 38 | | throw new ArgumentNullException(nameof(boundary)); |
| | 39 | | } |
| | 40 | |
|
| 88 | 41 | | if (stream == null) |
| | 42 | | { |
| 0 | 43 | | throw new ArgumentNullException(nameof(stream)); |
| | 44 | | } |
| | 45 | |
|
| 88 | 46 | | if (bufferSize < boundary.Length + 8) // Size of the boundary + leading and trailing CRLF + leading and trai |
| | 47 | | { |
| 0 | 48 | | throw new ArgumentOutOfRangeException(nameof(bufferSize), bufferSize, "Insufficient buffer space, the bu |
| | 49 | | } |
| 88 | 50 | | _stream = new BufferedReadStream(stream, bufferSize); |
| 88 | 51 | | _boundary = new MultipartBoundary(boundary, false); |
| | 52 | | // This stream will drain any preamble data and remove the first boundary marker. |
| | 53 | | // TODO: HeadersLengthLimit can't be modified until after the constructor. |
| 88 | 54 | | _currentStream = new MultipartReaderStream(_stream, _boundary) { LengthLimit = HeadersLengthLimit }; |
| 88 | 55 | | } |
| | 56 | |
|
| | 57 | | /// <summary> |
| | 58 | | /// The limit for the number of headers to read. |
| | 59 | | /// </summary> |
| 0 | 60 | | public int HeadersCountLimit { get; set; } = DefaultHeadersCountLimit; |
| | 61 | |
|
| | 62 | | /// <summary> |
| | 63 | | /// The combined size limit for headers per multipart section. |
| | 64 | | /// </summary> |
| 0 | 65 | | public int HeadersLengthLimit { get; set; } = DefaultHeadersLengthLimit; |
| | 66 | |
|
| | 67 | | /// <summary> |
| | 68 | | /// The optional limit for the total response body length. |
| | 69 | | /// </summary> |
| 0 | 70 | | public long? BodyLengthLimit { get; set; } |
| | 71 | |
|
| | 72 | | public async Task<MultipartSection> ReadNextSectionAsync(CancellationToken cancellationToken = new CancellationT |
| | 73 | | { |
| | 74 | | // Drain the prior section. |
| 1360 | 75 | | await _currentStream.DrainAsync(cancellationToken).ConfigureAwait(false); |
| | 76 | | // If we're at the end return null |
| 1360 | 77 | | if (_currentStream.FinalBoundaryFound) |
| | 78 | | { |
| | 79 | | // There may be trailer data after the last boundary. |
| 88 | 80 | | await _stream.DrainAsync(HeadersLengthLimit, cancellationToken).ConfigureAwait(false); |
| 88 | 81 | | return null; |
| | 82 | | } |
| 1272 | 83 | | var headers = await ReadHeadersAsync(cancellationToken).ConfigureAwait(false); |
| 1272 | 84 | | _boundary.ExpectLeadingCrlf = true; |
| 1272 | 85 | | _currentStream = new MultipartReaderStream(_stream, _boundary) { LengthLimit = BodyLengthLimit }; |
| 1272 | 86 | | long? baseStreamOffset = _stream.CanSeek ? (long?)_stream.Position : null; |
| 1272 | 87 | | return new MultipartSection() { Headers = headers, Body = _currentStream, BaseStreamOffset = baseStreamOffse |
| 1360 | 88 | | } |
| | 89 | |
|
| | 90 | | private async Task<Dictionary<string, StringValues>> ReadHeadersAsync(CancellationToken cancellationToken) |
| | 91 | | { |
| 1272 | 92 | | int totalSize = 0; |
| 1272 | 93 | | var accumulator = new KeyValueAccumulator(); |
| 1272 | 94 | | var line = await _stream.ReadLineAsync(HeadersLengthLimit - totalSize, cancellationToken).ConfigureAwait(fal |
| 3812 | 95 | | while (!string.IsNullOrEmpty(line)) |
| | 96 | | { |
| 2540 | 97 | | if (HeadersLengthLimit - totalSize < line.Length) |
| | 98 | | { |
| 0 | 99 | | throw new InvalidDataException($"Multipart headers length limit {HeadersLengthLimit} exceeded."); |
| | 100 | | } |
| 2540 | 101 | | totalSize += line.Length; |
| 2540 | 102 | | int splitIndex = line.IndexOf(':'); |
| 2540 | 103 | | if (splitIndex <= 0) |
| | 104 | | { |
| 0 | 105 | | throw new InvalidDataException($"Invalid header line: {line}"); |
| | 106 | | } |
| | 107 | |
|
| 2540 | 108 | | var name = line.Substring(0, splitIndex); |
| 2540 | 109 | | var value = line.Substring(splitIndex + 1, line.Length - splitIndex - 1).Trim(); |
| 2540 | 110 | | accumulator.Append(name, value); |
| 2540 | 111 | | if (accumulator.KeyCount > HeadersCountLimit) |
| | 112 | | { |
| 0 | 113 | | throw new InvalidDataException($"Multipart headers count limit {HeadersCountLimit} exceeded."); |
| | 114 | | } |
| | 115 | |
|
| 2540 | 116 | | line = await _stream.ReadLineAsync(HeadersLengthLimit - totalSize, cancellationToken).ConfigureAwait(fal |
| | 117 | | } |
| | 118 | |
|
| 1272 | 119 | | return accumulator.GetResults(); |
| 1272 | 120 | | } |
| | 121 | | } |
| | 122 | | } |