- LICENSE: the GNU Affero General Public License, version 3 (verbatim
from gnu.org).
- SPDX-License-Identifier: AGPL-3.0-only plus a copyright line on every
first-party source file (Rust, shell, Python, PHP); vendored crates keep
their own licenses.
- Cargo manifests carry license/authors/repository; the macOS bundle
copyright and the About page state the license and link the source.
- Release zips (and the macOS app bundle) include LICENSE.
- README: License section.
- sync: timestamps and tombstones in the shared file are clipped to the
local clock, and an edit wins a tie with a deletion, so a forged
future-dated record can no longer override every later local change
(or keep deleting a re-created profile) for as long as the forged date.
- write_private: the temp file is created O_EXCL under a random name, so a
symlink pre-placed in a shared folder can't be followed or overwritten.
- Vault/keychain reads return Zeroizing<String>; has_sync_password is
cached for a few seconds instead of fetching the real value every frame.
- generate_ssh_key creates a missing ~/.ssh as 0700.
- Honest wording: encrypted exports and the sync file carry login-script
values; the audit entry, the Settings hint and the docs now say so.
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.
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.
- 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.
Andy Dixon