src/Http/WebUtilities/test/BufferedReadStreamTests.cs - main - githubmirror/aspnetcore

src/Http/WebUtilities/test/BufferedReadStreamTests.cs
79 строк3 KB
Korolev Dmitry
Enforce MultipartHeadersLengthLimit across BufferedReadStream buffers (#67840)
20 июл 2026, 20:27
20 июл 2026, 20:27dfe3e58
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System.Text;

namespace Microsoft.AspNetCore.WebUtilities;

public class BufferedReadStreamTests
{
    [Fact]
    public async Task ReadLineAsync_LineWithinSingleBuffer_Succeeds()
    {
        var stream = MakeStream("hello world\r\n", bufferSize: 4096);

        var line = await stream.ReadLineAsync(lengthLimit: 100, CancellationToken.None);

        Assert.Equal("hello world", line);
    }

    [Fact]
    public async Task ReadLineAsync_LineSpanningMultipleBuffersWithinLimit_Succeeds()
    {
        var content = new string('a', 100);
        var stream = MakeStream(content + "\r\n", bufferSize: 16);

        var line = await stream.ReadLineAsync(lengthLimit: 1000, CancellationToken.None);

        Assert.Equal(content, line);
    }

    [Fact]
    public async Task ReadLineAsync_LineSpanningMultipleBuffersExceedingLimit_Throws()
    {
        // The line is larger than both the buffer size and the length limit, so it spans
        // several internal buffers before the limit is reached.
        var stream = MakeStream(new string('a', 100) + "\r\n", bufferSize: 16);

        var exception = await Assert.ThrowsAsync<InvalidDataException>(
            () => stream.ReadLineAsync(lengthLimit: 40, CancellationToken.None));
        Assert.Equal("Line length limit 40 exceeded.", exception.Message);
    }

    [Fact]
    public async Task ReadLineAsync_UnterminatedLineExceedingLimit_ThrowsInsteadOfAccumulating()
    {
        // No CRLF terminator, using the real default buffer (4 KiB) and header limit (16 KiB).
        // The limit must be enforced while reading rather than accumulating the whole payload.
        var stream = MakeStream(new string('a', 100_000), bufferSize: 1024 * 4);

        var exception = await Assert.ThrowsAsync<InvalidDataException>(
            () => stream.ReadLineAsync(lengthLimit: 1024 * 16, CancellationToken.None));
        Assert.Equal("Line length limit 16384 exceeded.", exception.Message);
    }

    [Fact]
    public void ReadLine_LineSpanningMultipleBuffersExceedingLimit_Throws()
    {
        var stream = MakeStream(new string('a', 100) + "\r\n", bufferSize: 16);

        var exception = Assert.Throws<InvalidDataException>(() => stream.ReadLine(lengthLimit: 40));
        Assert.Equal("Line length limit 40 exceeded.", exception.Message);
    }

    [Fact]
    public void ReadLine_LineSpanningMultipleBuffersWithinLimit_Succeeds()
    {
        var content = new string('a', 100);
        var stream = MakeStream(content + "\r\n", bufferSize: 16);

        var line = stream.ReadLine(lengthLimit: 1000);

        Assert.Equal(content, line);
    }

    private static BufferedReadStream MakeStream(string text, int bufferSize)
    {
        return new BufferedReadStream(new MemoryStream(Encoding.UTF8.GetBytes(text)), bufferSize);
    }
}