Hyrum's Law dictates that if we do not prevent naughty behavior,
people will rely on it. If we do not validate that the provided
file descriptor is correct today, it will be near impossible
to add proper validation checks later on.
The logic added validates that the provided file descriptor is
correct according to the same semantics as protoc,
which was reversed engineered to derive the set of rules implemented here.
The rules are unfortunately complicated because protobuf is a language
full of many non-orthogonal features. While our logic is complicated,
it is still 1/7th the size of the equivalent C++ code!
Change-Id: I6acc5dc3bd2e4c6bea6cd9e81214f8104402602a
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/184837
Reviewed-by: Damien Neil <dneil@google.com>
The internal/fileinit package is split apart into two packages:
* internal/filedesc constructs descriptors from the raw proto.
It is very similar to the previous internal/fileinit package.
* internal/filetype wraps descriptors with Go type information
Overview:
* The internal/fileinit package will be deleted in a future CL.
It is kept around since the v1 repo currently depends on it.
* The internal/prototype package is deleted. All former usages of it
are now using internal/filedesc instead. Most significantly,
the reflect/protodesc package was almost entirely re-written.
* The internal/impl package drops support for messages that do not
have a Descriptor method (pre-2016). This removes a significant amount
of technical debt.
filedesc.Builder to parse raw descriptors.
* The internal/encoding/defval package now handles enum values by name.
Change-Id: I3957bcc8588a70470fd6c7de1122216b80615ab7
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/182360
Reviewed-by: Damien Neil <dneil@google.com>