We don't need to special-case `NotFound` errors because
`ssh_key::PrivateKey::from_openssh` doesn't read from disk (so it
shouldn't be returning `NotFound` errors in the first place).
Previously, this condition made sense because we were using
`ssh_key::PrivateKey::read_openssh_file` instead of
`ssh_key::PrivateKey::from_openssh`, which _does_ read from disk. This
condition should have been removed in !1263 (the refactoring where we
switched to `from_openssh`).
(Also, after #901 is implemented, we probably won't have an
`Error::NotFound` error anymore).
The functions that handle OpenSSH-formatted keys now no longer read or
write from disk. This commit updates their names and doc strings to stop
suggesting they do.
This moves the filesystem calls from the `ssh` module to
`ArtiNativeKeyStore`. While `ArtiNativeKeyStore` shouldn't be concerning
itself with filesystem operations either, that refactoring will be
tackled separately (see arti#899).
This simplifies usage quite a bit and will enable us to implement a
dummy `KeyMgr` that doesn't depend on the error types from tor-keymgr
(which will replace the "real" `KeyMgr` if the keymgr feature is
disabled).
The HS `HsClientSpecifier` and `HsClientSecretKeySpecifier` are moved to
`tor-hsclient`. The HS service secret key specifier stubs are moved to
`tor-hsservice`.
This means `KeyMgr` users don't need to specify the underlying key type
(e.g. `ed25519::Keypair`) when retrieving keys. Instead, they can just
specify the type required (as long as it implements `ToEncodableKey`),
e.g. `HsClientIntroAuthKeypair`.
This adds a proof-of-concept `SshKeyType::read_ssh_format_erased`
implementation for `KeyType`. The implementation decodes an OpenSSH key
and converts it to one of the key types used internally by Arti. The
value returned is type-erased, and will be downscast later down the line
by the `KeyMgr` (note: `KeyMgr` doesn't exist yet).
The `SshKeyType::write_ssh_format` will be implemented once these APIs
are a bit more stable.
Gabriela Moldovan
Ian Jackson
Alexander Færøy