Profiles can be kept in step across machines through any folder they
share (cloud drive, network share, git checkout): one file,
nexus-profiles.nexus, in the encrypted-export format under a sync
password kept in the keychain/vault. Each sync merges profile by profile
(newest updated_at wins), propagates deletions as dated tombstones (an
edit after a deletion brings the profile back; tombstones expire after
180 days), validates every incoming profile, writes the file only when
it changed, and never syncs credentials.
Settings → Security → Profile sync picks the folder and sets the
password; syncs run at launch, 3 s after a profile change, every 10
minutes and on Sync Now (automatic runs stay quiet unless something
changed). An end-to-end test drives create, edit and delete between two
data directories sharing a folder.
Registration now opens with CAP LS 302 (servers without IRCv3 ignore it
and register as before). From the offered capabilities (multi-line LS
lists included) the client requests server-time and, when the profile
enables it, sasl; then AUTHENTICATE PLAIN with the account (defaulting
to the nick) and a stored SASL password (irc-sasl-password), base64 in
400-byte chunks, and CAP END on success or failure — failures are shown
on the Server tab and the connection carries on (NickServ still works).
server-time tags stamp events with the server's clock, so replayed
history shows real times.
Tested against the fake IRC server: multi-line LS, REQ/ACK, the PLAIN
exchange, 903, CAP END, and a tagged message's timestamp.
- Host certificates: certificate authorities are trusted per OpenSSH host
pattern (stored as @cert-authority known-hosts rows, matched against
'host' or '[host]:port' as OpenSSH does, with *, ? and !). For a host a
CA covers, the client asks for a certificate; one signed by a matching
CA, of host type, naming the host and in date is trusted without a
first-use prompt, and anything else is refused. Hosts no CA covers keep
the existing key checks. Applies to jump hosts and tunnels too.
- User certificates: <key>-cert.pub next to the configured private key is
used for publickey login (falling back to the plain key).
- Settings → Known Hosts: import ~/.ssh/known_hosts (hashed names and
@revoked lines skipped and counted), export in OpenSSH format, and a
Trust a CA form.
Verified against OpenSSH sshd with ssh-keygen-issued certificates: host
cert accepted without prompting and user-cert login with only
TrustedUserCAKeys; a CA for other hosts falls back to the key check; a
different CA is refused.
The tab layout (tab order and names, pins, the active tab, split trees
with their ratios) is saved whenever it changes — checked once a second,
written only on change, so it survives a crash — and reopened at the
next launch: saved profiles reconnect and local shells start in the
directory they were in (on Linux the live /proc cwd, so it isn't one
command behind). Quick Connect tabs and placeholder panes are skipped.
A General setting turns it off; it never runs when launched with
--connect, --run-local or --open, and screenshot runs never save.
Verified: a local tab left in /usr/share came back there with a
'Restored 1 tab(s)' toast.
An RDP profile can name a Kerberos KDC; CredSSP then authenticates with
Kerberos instead of NTLM, reaching the KDC through a small TCP client
(RFC 4120 length-prefixed framing, 5 s connect / 10 s read timeouts,
replies capped at 1 MiB so a hostile KDC can't force a huge allocation).
UDP KDCs are refused with a clear message. Tested against a fake KDC
(round trip, oversized reply, UDP); not against a real realm.
Smart-card logon is not implemented: it needs PC/SC hardware and a card
to build and test against.
RDP profiles can go through a Remote Desktop Gateway (MS-TSGU over an
HTTPS WebSocket) with its own username and password, stored like other
credentials (rdp-gateway-password). The gateway stream is bridged to a
loopback socket so the blocking RDP client uses it like any transport.
IronRDP's gateway crate (0.0.1) is vendored with fixes: it used
ironrdp-tls, which accepts any certificate, before sending Basic
credentials — the gateway is now verified against the web PKI; its
asserts on gateway-supplied lengths are errors instead of panics; and
the server port is passed through. Checked against a self-signed
openssl s_server: the connection is refused ('invalid peer certificate')
before any request or credential is sent. Not tested against a real
gateway; Basic-auth gateways only (no NTLM).
An optional 'Nexus Terminal' printer (IronRDP's PostScript driver
announce) appears on the remote desktop; each job is written to
'Nexus print <time>.ps' in Downloads, with a toast saying where. Jobs
are capped at 256 MiB and empty jobs leave no file. The shared drive and
the printer now share one RDPDR backend (rdp_devices); the printer
works on every platform, the drive on Linux and macOS.
Tested with a unit test driving create/write/close; xrdp has no printer
redirection, so not exercised against a server.
- Audio: the RDPSND channel with IronRDP's cpal playback backend (PCM;
Opus left out to avoid another native library). On by default for new
RDP profiles. Building now needs the ALSA headers on Linux
(libasound2-dev), added to CI, release and fuzz jobs and the build docs.
- Shared folder (Linux/macOS): one local folder appears on the remote
desktop as a drive. IronRDP's native backend joins server paths onto
the share unchecked, so it is wrapped in ConfinedDrive: create, list
and rename paths with '..' components, NUL bytes, or that resolve
through a symlink outside the share are refused (ACCESS_DENIED);
tests cover the escapes.
Verified against xrdp (with FUSE): the remote read the shared file, and
writes, mkdir and rename landed in the local folder. Not verified:
audio playback (the test container has no sound module), and xrdp lists
the drive as 'ignored' and can't list its directories (an IronRDP/xrdp
naming and listing mismatch, fixed upstream for the name).
A CLIPRDR channel with a text-only backend (CF_UNICODETEXT): text copied
on the remote desktop is fetched and goes through the app's remote-
clipboard preference like VNC and OSC 52; local text is offered to the
remote when the desktop gains focus, on Ctrl+V and with Paste Clipboard
(which no longer types the text). Backend callbacks run inside the
active stage, so they queue requests that the session loop sends.
Verified against xrdp: the remote X clipboard read back the offered
text, and a remote copy arrived through on_clipboard.
rust/fuzz (cargo-fuzz, nightly, its own workspace with the same IronRDP
patches) has targets for the Telnet IAC parser, the IRC parser + state
machine + mIRC formatter, VNC framebuffer updates and decoders,
~/.ssh/config parsing and the update manifest. They reach the private
parsers through hidden entry points behind nexus-core's 'fuzzing'
feature. A nightly workflow runs each for two minutes and uploads any
crashing input. A first 45 s run of each locally found nothing.
- Credential callbacks (SecretFn) now return Zeroizing<String>, as do the
session-only/pending caches they read and the RDP client's password,
so Nexus's own copies are wiped; a plain String copy is made only
where a library API needs one (SSH password auth, IRC, VNC, CredSSP).
- Release builds disable core dumps (RLIMIT_CORE 0) and, on Linux, mark
the process non-dumpable (PR_SET_DUMPABLE 0), which also blocks ptrace
attach and /proc/<pid>/mem reads by other processes of the same user.
Debug builds are unchanged so they stay debuggable. Verified on the
release binary: core limit 0, /proc/<pid>/{environ,mem} root-owned and
unreadable, local shells (including cwd capture) still work.
Closes the remaining parts of SEC-20261012-007 that the app controls;
egui's internal text buffers remain outside its reach.
The app now writes a diagnostic log to nexus.log in the data directory
(0600, rotated at 5 MiB): connection attempts and results, remote
closes, reconnect scheduling, host-key/certificate checks with the
policy applied, and credentials that couldn't be stored (kind only).
Credentials and terminal data are never logged. RUST_LOG sets the level
and also mirrors the log to stderr. The remaining eprintln! diagnostics
in storage and URL handling go through it too.
Every client's reader thread (Telnet/RAW, serial, local shell, IRC, VNC,
RDP) and SSH's channel reader task now run under clients::guarded /
guarded_task. A panic there, such as a decoder bug triggered by a
hostile server, reports 'internal error: …' through the session's
on_error and then closes it, so the tab shows the error (and
auto-reconnect can run) instead of looking connected with nothing
reading. Other sessions were already unaffected since the switch to
parking_lot locks.
- Protocol::Rdp with RdpConfig (domain, password mode, certificate
policy, TLS-only fallback, fixed or tab-sized resolution, SOCKS5/HTTP
proxy, SSH tunnel); migration 008 adds rdp_config and drops the
protocol CHECK constraint so new protocols no longer need a rebuild.
- Session manager: connect_rdp dials directly, via the shared proxy
module (proxy password from the secret store) or an SSH tunnel; the
server certificate goes through the known-hosts check (key type
rdp-tls); a tab-sized desktop uses the tab's reported pixel size, and
resizes wait until the server opens Display Control. Rejected NLA
passwords count as auth failures, so a saved one is asked again.
- The VNC viewer becomes DesktopView for both protocols; a small adapter
turns its keysyms and pointer masks into RDP scancodes, Unicode keys,
buttons and wheel events. For RDP, Paste Clipboard types the text.
- Profile editor RDP section, Quick Connect, badges, docs.
Verified against xrdp in the app: logon, desktop, input, and connections
through SOCKS5 and HTTP CONNECT relays. Not verified here: Windows/NLA
servers, the SSH tunnel route, and Display Control resizing (xrdp
0.9.24 never opened the channel).
clients::rdp connects over any caller-dialled TCP stream (direct, proxy
or SSH tunnel), upgrades to TLS and logs on with NLA (CredSSP/NTLM),
optionally falling back to TLS-only logon for servers without NLA such
as xrdp (credentials are passed so they log straight in). The server
certificate is pinned through a caller check on its SHA256 fingerprint
before any credentials are sent. The desktop decodes into the VNC
client's RGBA framebuffer; input (IronRDP's scancode/Unicode/mouse
operations), Display Control resizes and the deactivation-reactivation
sequence run on the session thread.
IronRDP's releases need three vendored patches (vendor/README.md):
picky and sspi with their RustCrypto release-candidate pins relaxed so
they share russh's stable versions (their own suites, 402 tests, pass
against them), and ironrdp-session with two unreleased upstream bitmap
fixes (#1486 stride, #1524 RDP6 orientation) without which xrdp desktops
render sheared.
Verified live against xrdp (scottyhardy/docker-remote-desktop): logon,
full desktop rendering, keyboard and mouse input.
SSH's async SOCKS5 and HTTP CONNECT code moves to clients::proxy as a
blocking dialer (SSH runs it on a blocking thread), so RDP and others can
use the same implementation. The proxy handshake now has a read timeout,
and new tests drive both proxy types against fake proxies, including
SOCKS5 username/password auth and a refused HTTP CONNECT (407).
The Go-generated link.db, profiles.link and rec1.cast fixtures and the
tests that read them are removed. Their coverage is kept by tests on
data this build writes: a fresh database round-trips SSH profiles (env
vars, login scripts, forwards), serial profiles, IRC room state, known
hosts, snippets and preferences, and encrypted exports round-trip and
reject a wrong password. The import dialog no longer offers .link files
and the docs stop mentioning them.
Unlock now always checks the verifier, so an empty vault can never
accept a wrong master password and the 'verify against the first entry'
fallback for Go/older vaults is gone. A vault without a verifier is
refused with a message naming the file to remove (SEC-20261012-016).
The Go vault fixture and its test go with it.
Keychain reads no longer fall back to the AlchementaryLink service and
copy entries forward, and Windows Credential Manager entries use
keyring's own target naming instead of go-keyring's 'service:user'.
Credentials saved by Alchementary Link, or by earlier builds on Windows,
are no longer found and need re-entering.
Startup no longer looks for an AlchementaryLink data directory to copy
into NexusTerminal, and the 'Imported your Alchementary Link data' toast
and the migration docs are gone. Existing Alchementary Link installs are
no longer picked up automatically.
SshConfig no longer has proxyPassword or totpSecret fields, so neither
can sit in clear in nexus.db or travel in an export. The proxy password
is a SecretKind (profile:<id>:proxy-password) edited like other saved
credentials and purged with the profile; the session manager hands both
it and the TOTP seed to the SSH client from the keychain/vault at
connect time.
This drops compatibility with Go-era profiles and .link/.nexus files
that carry these values inline: they are ignored on read and must be
re-entered (SEC-20261012-011).
Seeded pseudo-random input, biased towards each parser's control bytes,
is fed to the IRC line parser and state machine (plus mIRC formatting),
Telnet IAC negotiation, VNC framebuffer updates (including ZRLE behind a
real zlib stream, with a check that the decoders are actually reached),
~/.ssh/config parsing and the update manifest. None panic, and Telnet's
pending buffer stays bounded.
These run on stable in every CI run; they are not coverage-guided, so a
cargo-fuzz setup (nightly) remains a possible follow-up.
Session-only credentials (kept for a whole session so reconnects don't
re-prompt), credentials pending until a connection succeeds, and the
credential prompt's text buffer are now Zeroizing and wiped when
dropped, including when a prompt is cancelled or abandoned
(SEC-20261012-007, partial).
Still open: the values handed to the protocol clients are plain Strings
for the duration of authentication, egui keeps its own copies of typed
text, and no mlock/PR_SET_DUMPABLE is applied.
The working-directory capture (used to restart a local shell where it
left off) ran /usr/sbin/lsof inside write(), so each Enter in a macOS
local tab waited for a subprocess. On macOS the lookup now runs on a
background thread, triggered by the shell's next output after a line is
entered, so it sees the directory after the command; a failed lookup
keeps the last known directory. Linux keeps the cheap /proc readlink
(F10). Not exercised on macOS in this environment.
Every refresh looked up the latest commit of every repository (up to
5000), which can exhaust the API's hourly rate limit and then surfaces as
'authentication failed'. Lookups are now cached per repo against its
pushed_at, definite misses (404/409) included, and at most 100 new lookups
run per refresh, most recently pushed first (F13).
Startup wrote and deleted a probe item to see whether the keychain works,
waking D-Bus on Linux and risking a Keychain prompt on macOS. A read of a
missing entry answering 'no entry' proves the same; if a later write is
refused anyway, set_checked already falls back to the vault (F11).
Not verified against a live Secret Service or macOS Keychain in this
environment (no secret service here; the probe correctly reports it
unavailable).
- Quick Connect runs the same validation as saved profiles, so an SSH
connection without a username fails up front with a clear message (F5).
- ~/.ssh/config imports fill a missing User (and jump-host user) with the
local user name, as ssh does, and skip blocks that still don't validate,
reporting how many (F6).
- An unrecognised hostKeyPolicy/lineEnding/parity/flowControl/direction in
a stored config falls back to that field's default instead of failing
the whole JSON column and silently resetting every other setting; parse
failures that remain are logged (F7).
- A JSON export without secrets now blanks login-script 'send' steps that
answer a password-like 'wait' prompt (SSH and Telnet), not just the
proxy password and inline TOTP seed (SEC-20261012-011, partial).
- Credential kinds were string literals in the session manager, profile
editor and secret store; they are now SecretKind with one ALL list, so
the profile-delete purge can't miss a kind (F19).
Moving proxyPassword out of the profile record is left open: it changes
.link/.nexus compatibility with the Go app and needs an owner decision.
An empty vault accepted any password, so a typo at the first unlock
encrypted later secrets under the wrong key. New vaults store a verifier
(a known value sealed under the key) that every unlock must open. Vaults
from Go or older builds keep today's behaviour and gain a verifier on
their next write; Go ignores the extra field (SEC-20261012-016, F8).
- IRC: channel state is kept only for rooms the client itself joined, so
JOIN/PART/KICK/NAMES for other rooms can't grow it; users per channel
are capped at 10 000 and the view keeps at most 200 conversations,
dropping the oldest idle query (SEC-20261012-014, F14).
- Recordings: the list reads the header line and the last 64 KiB for the
duration instead of whole files of up to 250 MiB, falling back to a
full scan only when the final event is longer than the window
(SEC-20261012-020, F9).
- Audit log: keeps the newest 10 000 entries (F17).
Every shared lock was std::sync::Mutex with lock().unwrap() (~150 sites),
so a panic in any session's reader or callback poisoned the lock and the
next UI frame panicked too, dropping every open session. Locks are now
parking_lot::Mutex (no poisoning; already in the dependency tree), and a
panic hook reports worker panics as an error toast instead of the session
silently stopping (F3, F4).
A password typed at a 'saved' prompt was stored before the server
accepted it, so a typo was persisted and silently retried on every
reconnect. Typed values are now held per attempt and written once the
session connects; when the server refuses a saved credential the next
attempt asks again and the new value replaces it on success. A store
failure (keychain refused, vault locked) now shows a toast instead of
being swallowed, and reconnect prompts wait 5 minutes like the first
connect (SEC-20261012-015, F1, F2, F20).
OSC 52 and VNC ServerCutText now go through one handler that honours
'allow remote clipboard' and always toasts the first line, so a silent
clipboard swap can't set up a paste into another shell (SEC-20261012-010).
Multi-line pastes into a terminal without bracketed paste ask first, with a
preview (SEC-20261012-017). The launch-time update check can be turned off
and the updater docs no longer claim it is opt-in; the unused GitHub
fallback is removed (SEC-20261012-013, F15).
Under the 'ask' policy a changed host key used to be a hard error. The
prompt now shows the stored and received fingerprints and offers Reject,
Accept Once (connect, keep the record) and Accept & Update (replace the
record; audited). Unknown keys gain an Accept Once option too. Strict and
accept-new still refuse changed keys without prompting. Known-host rows
written by the old app are confirmed removable by id (test).
The NickServ password (and any other "remember for this session" secret) was
resolved through a fresh per-connect cache, so every auto-reconnect prompted
again with a 60 s timeout and an unanswered prompt failed the reconnect.
Session-only secrets now live on the session, survive auto and explicit
reconnects, and IDENTIFY is sent on every registration as before.
- The VNC client refuses desktop sizes over 64 Mpx (ServerInit and
DesktopSize/ExtendedDesktopSize) and ZRLE rectangles over 64 MiB before
allocating, so a hostile server can't force a multi-gigabyte allocation.
- Release URLs from the update manifest and repository URLs from the GitHub
API are handed to the system opener only when they are http(s) links.
- SSH key pairs are generated with ssh-key (Ed25519/ECDSA P-256/RSA) and
encrypted in-process, so the passphrase no longer appears as an ssh-keygen
command-line argument visible in the process list.
- open_tunnel's loopback bridge checks the accepted peer is our own client
socket, so a local process racing for the ephemeral port can't be spliced
into the IRC/VNC SSH tunnel.
- run_command caps buffered output at 1 MiB; local-forward abort handles are
pruned as connections finish; SOCKS5 host/credential lengths over 255 bytes
are rejected instead of being truncated into a malformed request.
- Secrets::delete_profile removes every profile credential kind from the OS
keychain as well as the vault (previously only the vault was purged, so
keychain passwords/tokens outlived the profile).
- write_private writes to a sibling temp file and renames it into place, so a
crash mid-write cannot truncate the vault or an export, and a pre-existing
world-readable file is replaced rather than reused.
- Argon2-derived vault/export keys are Zeroizing and wiped on drop.
- Recordings (which capture typed input), JSON exports and --data-dir
directories are created owner-only.
Andy Dixon