When you say unknown fields- you mean that if hostA has an .proto schema of version N and hostB has a .proto schema of version M<N and when hostA would send a message to hostB, hostB would drop all fields its schema doesn't contain?
On Tuesday, 14 February 2017 19:21:16 UTC+2, Adam Cozzette wrote: > > You might be able to make this work, but it can be tricky to get it right > and so I wouldn't necessarily recommend it. One major problem is that maps > are serialized non-deterministically because they are logically unordered. > Another problem is unknown fields; if you're using proto3 then unknown > fields are dropped at parsing time, so when B parses and reserializes the > proto it will lose any unknown fields. > > On Sat, Feb 11, 2017 at 9:19 AM, Yacov Manevich <m.ya...@gmail.com > <javascript:>> wrote: > >> Hi all. >> >> We use protobuf in our product, and I have a question regarding >> incorporating it with signatures. >> If I have 2 hosts (let's assume they can be different platforms, OS, >> etc.) - hostA and hostB and the following scenario: >> >> A creates message M, sends B the message M, as well as the output of >> proto.Marshal >> <https://godoc.org/github.com/golang/protobuf/proto#Marshal> on M (the >> bytes) - denoted as Ma >> 1) A sends a message M to B via gRPC >> 2) B receives the message, and calls proto.Marshal >> <https://godoc.org/github.com/golang/protobuf/proto#Marshal> on M, >> denoted Mb. >> 3) B checks whether Ma is equal to Mb. >> >> Is Ma equal to Mb? >> >> I'm asking the question because I wish to sign messages in the following >> way: >> Defining a message M: >> message M { >> field1 ... >> fiedl2 ... >> ... >> bytes signature = n; >> } >> >> And then the sender would: >> 1) Nullify the signature >> 2) call proto.Marshal >> <https://godoc.org/github.com/golang/protobuf/proto#Marshal> >> 3) Hash the bytes >> 4) Sign the hash >> 5) Put the signature into M.signature >> 6) Send M over the wire >> >> The receiver would: >> 1) Backup the signature >> 2) Nullify the signature field >> 3) Call proto.Unmarshal >> <https://godoc.org/github.com/golang/protobuf/proto#Unmarshal> on M >> 4) hash the bytes >> 5) Verify the signature >> >> >> Would that work or not? >> >> >> Many thanks in advance, Yacov. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Protocol Buffers" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to protobuf+u...@googlegroups.com <javascript:>. >> To post to this group, send email to prot...@googlegroups.com >> <javascript:>. >> Visit this group at https://groups.google.com/group/protobuf. >> For more options, visit https://groups.google.com/d/optout. >> > > -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To unsubscribe from this group and stop receiving emails from it, send an email to protobuf+unsubscr...@googlegroups.com. To post to this group, send email to protobuf@googlegroups.com. Visit this group at https://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/d/optout.
