This establishes what our mailbox protocol does to encrypt the
individual (post-SPAKE2) messages, which combines NaCl SecretBox and our own
key-derivation choices. I'd like to move off of NaCl/libsodium and I think
some RFC7539-implementing library might be compatible, and with these test
vectors I can check that. I also want to copy these tests into the Rust port.
The flake8 config excludes E741, which would complain about using
'l' (lower-case ell) as a variable name. We use this for the Lister object in
one test that uses single-character variable names for all the machines ('b'
for Boss, 'm' for Mailbox, etc). That comment was added before excluding
E741. If we ever restore that warning, we might want to rename the variable.
This renames all the existing API methods, to use a consistent
"d=get_XYZ()" (for Deferred mode) or "dg.wormhole_got_XYZ()" (for Delegated
mode). It updates cmd_send/cmd_receive/cmd_ssh to use the new API.
Since we now have get_welcome(), apps handle the Welcome message with a
Deferred callback instead of registering a "welcome handler". This lets us
make sure we've finished printing any server message-of-the-day or "you
should update your client" message to stdout before using stdio to ask for
the wormhole code. (Previously, the code-input prompt was overwritten by the
server message, and it was ugly). refs #145. This approach adds an extra
roundtrip to the receiver, but we can fix that (see #145 for details).
Because of that change, the server-is-being-slow message is printed at a
slightly different time, so those tests needed some extra work to exercise it
properly.
Previously, w.when_verified() was documented to fire only after a valid
encrypted message was received, but in fact it fired as soon as the shared
key was derived (before any encrypted messages are seen, so no actual
"verification" could occur yet).
This fixes that, and also adds a new w.when_key() API call which fires at the
earlier point. Having something which fires early is useful for the CLI
commands that want to print a pacifier message when the peer is responding
slowly. In particular it helps detect the case where 'wormhole send' has quit
early (after depositing the PAKE message on the server, but before the
receiver has started). In this case, the receiver will compute the shared
key, but then wait forever hoping for a VERSION that will never come. By
starting a timer when w.when_key() fires, and cancelling it when
w.when_verified() fires, we have a good place to tell the user that something
is taking longer than it should have.
This shifts responsibility for notifying Boss.got_verifier, out of Key and
into Receive, since Receive is what notices the first valid encrypted
message. It also shifts the Boss's ordering expectations: it now receives
B.happy() before B.got_verifier(), and consequently got_verifier ought to
arrive in the S2_happy state rather than S1_lonely.
* InputHelper returns full words, not just suffixes. I liked the fact that
suffixes made it impossible to violate the "all matches will start with
your prefix" invariant, but in practice it was fiddly to work with.
* add ih.when_wordlist_is_available(), so the frontend can block (after
claiming the nameplate) until it can return a complete wordlist to
readline. This helps the user experience, because readline wasn't really
built to work with completions that change over time
* make the Wordlist responsible for appending hyphens to all non-final word
completions. InputHelper remains responsible for hyphens on nameplates.
This makes the frontend simpler, but I may change it again in the future if
it helps non-readline GUI frontends.
* CodeInputter: after claiming, wait for the wordlist rather than returning
an empty list
* PGPWordList: change to match
This has the unfortunate side-effect that e.g. typing "3-yucatan-tu TAB"
shows you completions that include the entire phrase: "3-yucatan-tumor
3-yucatan-tunnel", rather than only mentioning the final word. I'd like to
fix this eventually.
This also changes the can-I-run-wormhole check to use C.UTF-8 instead of
en_US.UTF-8, which seems necessary to hush Click on py3. See issue #127 for
more discusson.