`download()` is actually a general-purpose function for sending HTTP
requests on a stream. We will soon repurpose it for `POST`-ing
descriptors, so let's rename it to `send_request`.
The `KeypairData` type from [ssh-key] at some point leaked into the
keymgr API (via the `EncodableKey` trait). Instead of re-exporting just
`KeypairData`, let's re-export the entire `ssh_key` crate
(`EncodableKey` implementors would need additional types from `ssh_key`
to construct a `KeypairData` object anyway).
[ssh-key]: https://crates.io/crates/ssh-key
Previously, the Arti key store would store x25519 secret keys as ed25519
OpenSSH keys, which it would convert to x25519 upon loading (using the
conversion function added in !1297 (merged)). This approach isn't good
enough though: most people will probably want to bring their existing
x25519 keys, and in order to store those in OpenSSH format, we'd need
convert them to ed25519, which is impossible (because the secret part of
an x25519 key contains a SHA512'd secret, whereas the corresponding,
"un-expanded", ed25519 secret key contains the secret itself rather than
the SHA).
Now that `ssh-key` has support for ssh keys with [custom algorithm
names], we can store x25519 in OpenSSH format directly. This commit
changes the storage format used by the keymgr for x25519 client auth
keys (from ed25519-ssh to our own custom key type with an algorithm name
of `"x25519@torproject.org"`).
Closes#936
[custom algorithm names]: https://github.com/RustCrypto/SSH/pull/136
I had planned to make this code accept extensions of unknown type,
but for now I'm backing out of that plan: the set of extensions we
send influences the set that we're willing to receive.
Previously we were using backtrace 0.3.39, which has a [bug] that causes
it to segault in some circumstances. I experienced this bug while trying
to fix the minimal-versions build in !1508.
[bug]: https://github.com/rust-lang/backtrace-rs/issues/267
This is the API deficiency in ed25519-dalek v1 that allows you to
mismatch public and private keys, leading to a (fatal)
double-signing attack. We have worked around this in our current
design, so it's appropriate to suppress this warning for now.
This should be enough now to establish real introduction points,
though there is still a lot of work to do. Part of #976.
This has been rebased and edited to incorporate discussions from
!1465.
These values are computed as part of the circuit extension
handshake, and are used as MAC keys to bind `ESTABLISH_INTRO`
messages to a particular circuit so that they can't be replayed.
Part of #993.
This allows us to allow passing in opaque HsMacKey objects,
rather than untyped byte slices.
Additionally, we now check both MAC and signature unconditionally,
to avoid the large timing side-channel. The small timing
side-channel of combining booleans with `&` is considered safe.
Part of #993.
This will be useful in preference to the regular Mac trait for the
places where we need to pass a Mac key around, but we don't need to
support incremental operation.
Part of arti#993, where we want to expose a MAC object without
exposing sensitive data.
This commit makes a trait function use another currently unused trait
function, thereby increasing the test coverage, as well as being
potentially more correct from a semantic point of view.
Gabriela Moldovan
Ian Jackson
Nick Mathewson
Emil Engler