Files
quic-go/http3/capsule_test.go
Benjamin M. Schwartz c7cf12703d quicvarint: tolerate empty reads of the underlying io.Reader (#5275)
* Tolerate empty reads in `quicvarint.Read`

Currently, `quicvarint.Read` misinterprets an empty read (`n==0`)
as a single zero byte.  While empty reads are "discouraged" in
the `io.Reader` interface, they do sometimes happen, especially
when using `io.Pipe()`.

This change tolerates empty reads, adds a corresponding unit test,
and also includes some additional test coverage related to empty
capsules

* minor test refactor

---------

Co-authored-by: Marten Seemann <martenseemann@gmail.com>
2025-08-05 08:05:52 +02:00

108 lines
2.6 KiB
Go

package http3
import (
"bytes"
"io"
"testing"
"github.com/quic-go/quic-go/quicvarint"
"github.com/stretchr/testify/require"
)
func TestCapsuleParsing(t *testing.T) {
b := quicvarint.Append(nil, 1337)
b = quicvarint.Append(b, 6)
b = append(b, []byte("foobar")...)
ct, r, err := ParseCapsule(bytes.NewReader(b))
require.NoError(t, err)
require.Equal(t, CapsuleType(1337), ct)
buf := make([]byte, 3)
n, err := r.Read(buf)
require.NoError(t, err)
require.Equal(t, 3, n)
require.Equal(t, []byte("foo"), buf)
data, err := io.ReadAll(r) // reads until EOF
require.NoError(t, err)
require.Equal(t, []byte("bar"), data)
}
func TestEmptyCapsuleParsing(t *testing.T) {
b := quicvarint.Append(nil, 1337)
b = quicvarint.Append(b, 0)
// Capsule content is empty.
ct, r, err := ParseCapsule(bytes.NewReader(b))
require.NoError(t, err)
require.Equal(t, CapsuleType(1337), ct)
data, err := io.ReadAll(r) // reads until EOF
require.NoError(t, err)
require.Equal(t, []byte{}, data)
}
// test EOF vs ErrUnexpectedEOF
func TestCapsuleTruncation(t *testing.T) {
t.Run("with content", func(t *testing.T) {
b := quicvarint.Append(nil, 1337)
b = quicvarint.Append(b, 6)
b = append(b, []byte("foobar")...)
testCapsuleTruncation(t, b)
})
t.Run("empty content", func(t *testing.T) {
b := quicvarint.Append(nil, 1337)
b = quicvarint.Append(b, 0)
testCapsuleTruncation(t, b)
})
}
func testCapsuleTruncation(t *testing.T, b []byte) {
for i := range b {
ct, r, err := ParseCapsule(bytes.NewReader(b[:i]))
if err != nil {
if i == 0 {
require.ErrorIs(t, err, io.EOF)
} else {
require.ErrorIs(t, err, io.ErrUnexpectedEOF)
}
continue
}
require.Equal(t, CapsuleType(1337), ct)
_, err = io.ReadAll(r)
require.ErrorIs(t, err, io.ErrUnexpectedEOF)
}
}
func TestCapsuleWriting(t *testing.T) {
var buf bytes.Buffer
require.NoError(t, WriteCapsule(&buf, 1337, []byte("foobar")))
ct, r, err := ParseCapsule(&buf)
require.NoError(t, err)
require.Equal(t, CapsuleType(1337), ct)
val, err := io.ReadAll(r)
require.NoError(t, err)
require.Equal(t, "foobar", string(val))
}
func TestCapsuleWriteEmpty(t *testing.T) {
var buf bytes.Buffer
require.NoError(t, WriteCapsule(&buf, 1337, []byte{}))
require.NoError(t, WriteCapsule(&buf, 1337, []byte{}))
ct, r, err := ParseCapsule(&buf)
require.NoError(t, err)
require.Equal(t, CapsuleType(1337), ct)
val, err := io.ReadAll(r)
require.NoError(t, err)
require.Empty(t, val)
ct, r, err = ParseCapsule(&buf)
require.NoError(t, err)
require.Equal(t, CapsuleType(1337), ct)
val, err = io.ReadAll(r)
require.NoError(t, err)
require.Empty(t, val)
}