if !timestamp.match /^[\da-f]+$/
raise Blob::InvalidSignatureError.new 'Timestamp is not a base16 number.'
end
- if timestamp.to_i(16) < db_current_time.to_i
+ if timestamp.to_i(16) < (opts[:now] or db_current_time.to_i)
raise Blob::InvalidSignatureError.new 'Signature expiry time has passed.'
end