*: Change default chunk payload string length

Closes #1032.

Signed-off-by: Evgenii Baidakov <evgenii@nspcc.io>

api/auth/center_test.go

@@ -318,7 +318,7 @@ func TestAwsEncodedChunkReader(t *testing.T) {
 
 	t.Run("err chunk header too long", func(t *testing.T) {
 		streamSigner := v4.NewChunkSigner("us-east-1", "s3", seedSignature, ts, awsCreds)
-		chunkThreeBody := make([]byte, 4097)
+		chunkThreeBody := make([]byte, v4.MaxChunkedPayloadLineLength+1)
 		for i := range chunkThreeBody {
 			chunkThreeBody[i] = 'a'
 		}
@@ -341,7 +341,7 @@ func TestAwsEncodedChunkReader(t *testing.T) {
 			_ = chunkedReader.Close()
 		}()
 
-		chunk := make([]byte, 4096)
+		chunk := make([]byte, v4.MaxChunkedPayloadLineLength)
 		payload := bytes.NewBuffer(nil)
 		_, err = io.CopyBuffer(payload, chunkedReader, chunk)
 

api/auth/signer/v4/chunked_reader.go

@@ -15,10 +15,13 @@ import (
 	"io"
 )
 
-const maxLineLength = 4096 // assumed <= bufio.defaultBufSize
+// MaxChunkedPayloadLineLength defines the maximum chunk payload length.
+// Considering https://github.com/aws/aws-sdk-go-v2/blob/9a211f9a8eb9923a47740503892928d702a2ac63/service/internal/checksum/aws_chunked_encoding.go#L15
+// as default value.
+const MaxChunkedPayloadLineLength = 1024 * 64
 
 var (
-	// ErrLineTooLong appears if chunk header exceeds maxLineLength.
+	// ErrLineTooLong appears if chunk header exceeds MaxChunkedPayloadLineLength.
 	ErrLineTooLong = errors.New("header line too long")
 
 	// ErrInvalidChunkSignature appears if passed chunk signature differs from calculated.
@@ -37,7 +40,7 @@ var (
 // The chunkedReader returns io.EOF when the final 0-length chunk is read.
 func NewChunkedReader(r io.ReadCloser, streamSigner *ChunkSigner) io.ReadCloser {
 	return &chunkedReader{
-		r: bufio.NewReader(r),
+		r: bufio.NewReaderSize(r, MaxChunkedPayloadLineLength),
 		// bufio.Reader can't be closed, thus left link to the original reader to close it later.
 		origReader:   r,
 		streamSigner: streamSigner,
@@ -184,7 +187,7 @@ func (cr *chunkedReader) Read(b []uint8) (n int, err error) {
 }
 
 // Read a line of bytes (up to \n) from b.
-// Give up if the line exceeds maxLineLength.
+// Give up if the line exceeds MaxChunkedPayloadLineLength.
 // The returned bytes are owned by the bufio.Reader
 // so they are only valid until the next bufio read.
 func readChunkLine(b *bufio.Reader) ([]byte, []byte, error) {
@@ -199,7 +202,7 @@ func readChunkLine(b *bufio.Reader) ([]byte, []byte, error) {
 		}
 		return nil, nil, err
 	}
-	if len(p) >= maxLineLength {
+	if len(p) >= MaxChunkedPayloadLineLength {
 		return nil, nil, ErrLineTooLong
 	}