This change does two things: 1. Fix a length checking bug in the Decrypt function. 2. Use binary.LittleEndian for byte conversions. Fixes golang/go#19881 Change-Id: I9d33b92f2bd7e6ca8f69308388f1e8a5c6df2be8 Reviewed-on: https://go-review.googlesource.com/39954 Reviewed-by: Adam Langley <agl@golang.org>