// Copy request.
	req := *r

	// Save authorization header.
	v4Auth := req.Header.Get(xhttp.Authorization)

	// Parse signature version '4' header.
	signV4Values, err := parseSignV4(v4Auth, region, stype)
	if err != ErrNone {
		return err
	}

	// Extract all the signed headers along with its values.
	extractedSignedHeaders, errCode := extractSignedHeaders(signV4Values.SignedHeaders, r)

				Signature:     "abcd",
			},
			expectedErrCode: ErrNone,
		},
	}

	for i, testCase := range testCases {
		parsedAuthField, actualErrCode := parseSignV4(testCase.inputV4AuthStr, "", "s3")

		if testCase.expectedErrCode != actualErrCode {
			t.Fatalf("Test %d: Expected the APIErrCode to be %d, got %d", i+1, testCase.expectedErrCode, actualErrCode)
		}

	// Copy request.
	req := *r

	// Save authorization header.
	v4Auth := req.Header.Get(xhttp.Authorization)

	// Parse signature version '4' header.
	signV4Values, errCode := parseSignV4(v4Auth, globalSite.Region(), serviceS3)
	if errCode != ErrNone {
		return cred, "", "", time.Time{}, errCode
	}

	// Payload streaming.
	payload := streamingContentSHA256
	if trailers {