Check for value > 7 days in X-Amz-Expires header. (#5163)

Add a check to see if the X-Amz-Expires header in the presigned URL is less than 7 days.

Fixes #5162

cmd/signature-v4-parser.go

@@ -188,6 +188,11 @@ func parsePreSignV4(query url.Values) (psv preSignValues, aec APIErrorCode) {
 	if preSignV4Values.Expires < 0 {
 		return psv, ErrNegativeExpires
 	}
+
+	// Check if Expiry time is less than 7 days (value in seconds).
+	if preSignV4Values.Expires.Seconds() > 604800 {
+		return psv, ErrMaximumExpires
+	}
 	// Save signed headers.
 	preSignV4Values.SignedHeaders, err = parseSignedHeader("SignedHeaders=" + query.Get("X-Amz-SignedHeaders"))
 	if err != ErrNone {