This will be useful for the upcoming "persistent wormhole" mode. A
client might send an allocation request, crash/terminate before
receiving a response, then restart, then re-send the request. If the
server sees a request with the same request_id a previous request, it
can return the same nameplate.
We'll need code changes on both sides to support this (nothing sends or
checks request_id yet), but this lands the schema change early to reduce
future disruption.
This will allow a future peer to figure out what transit modes we can
and cannot do, and thus avoid spinning up expensive modes that we won't
be able to use (e.g. WebRTC).
The new autobahn release removes the Twisted pin, so we no longer need
one. Depend on the new autobahn to flush out any environments that are
still using the old one (and thus can't use the current Twisted).
Thanks https://github.com/crossbario/autobahn-python/issues/680 !
This enhances the ACK that wormhole-receive returns when it finishes
receiving all the data to be a dictionary. The dict includes the SHA256
hash of everything it received, and the sender checks this for a match
before declaring the transfer to be a success. This guards against data
being shuffled somehow during transit.
This better reflects the purpose of the message. Key confirmation is a
side-effect.
This patch only changes the "phase:" name and the key-derivation string.
A subsequent patch will modify the function and variable names to match.
The file-send protocol now sends a "hints-v1" key in the "transit"
message, which contains a list of JSON data structures that describe the
connection hints (a mixture of direct, tor, and relay hints, for now).
Previously the direct/tor and relay hints were sent in different keys,
and all were sent as strings like "tcp:hostname:1234" which had to be
parsed by the recipient.
The new structures include a version string, to make it easier to add
new types in the future. Transit logs+ignores hints it cannot
understand.
In the future, both sides should expect to receive "transit" messages at
any time, and they will add to the list of hints that they should try.
For now, each side only sends a single transit message, before they send
the offer (sender) or answer (receiver).
This moves us slowly towards a file-transfer protocol that exchanges
multiple messages, with a single offer (sender->receiver) and
answer (receiver->sender), and one or more connection hint messages (in
either direction) that appear gradually over time as connection
providers come online.
At present the protocol still expects the whole hint list to be present
in the offer/answer message.
