## Summary

Release prep for v26.5.3 — Aetherial Audio TX completion + security
hardening + 100-commit reliability sweep.

- **CHANGELOG.md** — new v26.5.3 section: 138 commits across 14
contributors since v26.5.2.1
- **README.md** — version line bump 26.5.2.1 → 26.5.3
- **CMakeLists.txt** — already at 26.5.3 (set in #3024)

## Highlights

- **Aetherial Audio TX completion** — PAPR all-pass cascade + split-band
DESS, full per-stage CHAIN UI
- **Security advisories** — GHSA-wfx7-w6p8-4jr2 (WAN cert-pin Phase 2,
#3026) + GHSA-qxhr-cwrc-pvrm (CAT PTY symlink, #3027)
- **MQTT settings dialog refactor** (#3051, @s53zo) — JSON-array topics
+ button-event lists, nested-JSON consolidation
- **Audio reliability sweep** — WASAPI silent-open watchdog, mono-only
USB PnP mic recovery, MQTT subscribe diff
- **Native Hamlib NET rigctl** — eliminates external rigctld dependency
- **Stream Deck integration** — Elgato SDK plugin
(Win/Mac/Linux-via-OpenDeck)

## Contributors thanked

@jensenpat (16), @aethersdr-agent (22 bot), @NF0T (12), @rfoust (9),
@Ozy311 (5), @M7HNF-Ian (5), @chibondking (5), @M8WLO (4), @s53zo (2),
@pepefrog1234 (2), @K5PTB (2), @chrisb1964 (1)

## Test plan

- [ ] CI green (build + check-paths + check-windows)
- [ ] CHANGELOG renders correctly on GitHub
- [ ] README version banner shows 26.5.3
- [ ] After merge: tag v26.5.3 once CI green on main

73, Jeremy KK7GWY & Claude (AI dev partner)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

…ethersdr#2962)

Implements a native SmartCAT-compatible TCP CAT server, enabling band,
mode, and frequency sync with N1MM, fldigi, WSJT-X, MacLoggerDX, and
other logging/digital-mode software via the industry-standard CAT
protocol.

## Why CAT instead of rigctld

N1MM does not speak the Hamlib NET rigctl protocol; it requires a CAT
port (TS-2000 or FlexCAT dialect). This made a full CAT implementation
necessary for N1MM compatibility. Not1MM (a separate Linux-only product)
uses rigctld — that is covered by aethersdr#2975.

## Protocol coverage

- Full Kenwood TS-2000 command set per the manual appendix
- Full FlexCAT command set per SmartCAT User Guide v4.1.5, except
  commands not applicable to a Flex radio (see PR body for gap list)
- Two TCP ports; each port has a companion PTY that accepts the same
  commands — operators with existing SmartCAT/SmartDAX configurations
  can keep them unchanged

## Integration testing

Tested against real hardware (FlexRadio 6500, firmware 4.2.18):

| App          | Connection | Result |
|--------------|-----------|--------|
| fldigi       | TCP + PTY | ✓      |
| WSJT-X       | TCP + PTY | ✓      |
| MacLoggerDX  | TCP       | ✓      |
| N1MM+        | TCP       | ✓ (CAT sync; CW keying not possible — see below) |

Primary platform: macOS. Also tested on Raspberry Pi 5 / Raspberry Pi
OS Trixie.

### N1MM CW keying — known limitation

N1MM keys CW by toggling RTS/DTR on a real serial COM port. Virtual
serial ports (PTYs) are not exposed as COM ports in Windows, so RTS/DTR
keying cannot reach AetherSDR. No workaround exists without a
WinKeyer-compatible keyer emulator; documented here so operators don't
waste time chasing it.

## Test suites

- `CAT_TS-2000_test`: 15 sections, 103 checks (92 always-on + 11
  PTT/CW gated)
- `CAT_Flex_test`: 16 sections, 129 checks (105 always-on + 24
  PTT/CW gated)

PTT and CW keyer tests are **skipped by default** to avoid unintended
transmissions. Enable with `--ptt` and `--cw` when a radio is connected
and the operator is ready to transmit.

Firmware TX race noted during CW testing: the radio briefly reports
TX=0 via CAT while the PA is still hot after CW completes. Safety
watches added to the test suite; documented as known hardware behaviour.

## CAT applet redesign

Configuration moved to a pop-out window (port number, dialect, VFO A/B
slice assignment per port) rather than the right panel. Inspired by
SmartSDR for macOS but more intuitive. The pattern — space-consuming
config in a pop-out, status summary in the applet — is worth adopting
for other applets.

UI details: dynamic PTY-path column sizing; "Flex" dialect label (was
"FlexCAT"); VFO column widths; column stretch.

## Security

- Applied the PTY symlink fix (same pattern as GHSA-qxhr-cwrc-pvrm,
  aethersdr#3027) to CatPort: per-user symlink directories, atomic rename
  instead of unlink+symlink.

## Code quality

- UAF audit: SmartCatProtocol and the new RigctlProtocol additions are
  both clean — no `[this]` captures in queued lambdas; all dispatch is
  synchronous on the main thread.
- ThemeManager: `CatControlApplet` was included in the Phase 2 mass
  migration (aethersdr#3102). Because this branch replaces the entire applet,
  that migration did not carry forward. We applied
  `ThemeManager::applyStyleSheet()` throughout — both the docked panel
  and the pop-out window — so all widgets auto-restyle on `themeChanged`,
  consistent with the rest of the codebase. One intentional hardcode
  remains: the `:checked` background `#006040` (CAT active state); there
  is no `color.background.success` token analogous to
  `color.background.tx`. Adding one would complete the conversion and is
  worth proposing as a follow-up.

Closes aethersdr#2962

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

…ethersdr#2962)

Implements a native SmartCAT-compatible TCP CAT server, enabling band,
mode, and frequency sync with N1MM, fldigi, WSJT-X, MacLoggerDX, and
other logging/digital-mode software via the industry-standard CAT
protocol.

## Why CAT instead of rigctld

N1MM does not speak the Hamlib NET rigctl protocol; it requires a CAT
port (TS-2000 or FlexCAT dialect). This made a full CAT implementation
necessary for N1MM compatibility. Not1MM (a separate Linux-only product)
uses rigctld — that is covered by aethersdr#2975.

## Protocol coverage

- Full Kenwood TS-2000 command set per the manual appendix
- Full FlexCAT command set per SmartCAT User Guide v4.1.5, with the
  exception of ZZPA/ZZPE (panadapter data streaming — out of scope)
- Two TCP ports by default: 4532 (rigctld) and 5001 (FlexCAT); up to
  6 more ports can be configured. Each TCP port has a companion PTY
  that accepts the same commands and responds identically. PTY paths
  are shown in the pop-out applet and can be copied to the clipboard
  with a right-click.

## Integration testing

Tested against real hardware (FlexRadio 6500, firmware 4.2.18):

| App          | Connection | Result |
|--------------|-----------|--------|
| fldigi       | TCP + PTY | ✓      |
| WSJT-X       | TCP + PTY | ✓      |
| MacLoggerDX  | PTY (TS-2000 only) | ✓ |
| N1MM+        | TCP       | ✓ (CAT sync; CW keying not possible — see below) |

Primary platform: macOS. Also tested on Raspberry Pi 5 / Raspberry Pi
OS Trixie.

### N1MM CW keying — known limitation

N1MM keys CW by toggling RTS/DTR on a real serial COM port. Virtual
serial ports (PTYs) are not exposed as COM ports in Windows, so RTS/DTR
keying cannot reach AetherSDR. No workaround exists without a
WinKeyer-compatible keyer emulator; documented so operators don't waste
time chasing it.

## Test suites

- `CAT_TS-2000_test`: 15 sections, 103 checks (92 always-on + 11
  PTT/CW gated)
- `CAT_Flex_test`: 16 sections, 129 checks (105 always-on + 24
  PTT/CW gated)

PTT and CW keyer tests are **skipped by default** to avoid unintended
transmissions. Enable with `--ptt` and `--cw` when a radio is connected
and the operator is ready to transmit.

Firmware TX race noted during CW testing: the radio briefly reports
TX=0 via CAT while the PA is still hot after CW completes. Safety
watches added to the test suite; documented as known hardware behaviour.

## CAT applet redesign

Inspired by SmartSDR for macOS. The space-consuming configuration
belongs in a pop-out, not the applet panel. PTY paths for running ports
are shown in the table and can be copied to the clipboard with a
right-click — handy when configuring external apps.

## Security

- Applied the PTY symlink fix (same pattern as GHSA-qxhr-cwrc-pvrm,
  aethersdr#3027) to CatPort: per-user symlink directories, atomic rename
  instead of unlink+symlink.

## Code quality

- UAF audit: SmartCatProtocol and new RigctlProtocol additions both
  clean — no [this] captures in queued lambdas; all dispatch
  synchronous on main thread
- ThemeManager: CatControlApplet was included in the Phase 2 mass
  migration (aethersdr#3102). Because this branch replaces the entire applet,
  that migration did not carry forward. Applied
  ThemeManager::applyStyleSheet() throughout — both the docked panel
  and the pop-out window — so all widgets auto-restyle on themeChanged,
  consistent with the rest of the codebase. One intentional hardcode
  remains: the :checked background #006040 (CAT active state); there
  is no color.background.success token analogous to color.background.tx.
  Adding one would complete the conversion and is worth proposing as
  a follow-up.

Closes aethersdr#2962

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

…ation

The GHSA security fix (aethersdr#3027) moved PTY symlinks from /tmp/AetherSDR-CAT-*
to per-user directories (QStandardPaths::CacheLocation/cat-{A,B,C}).
All three integration test suites hardcoded the old /tmp paths as their
--pty default, causing section 14/15/16 to skip every run.

Replace each hardcoded string with a runtime-computed defaultPtyPath()
that mirrors CatPort::defaultSymlinkPath() exactly. The --pty override
still works for non-standard setups.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

…3131)

## CAT Protocol Coverage

- Full Kenwood TS-2000 command set, referencing the manual appendix,
except commands not applicable to a FlexRadio
- Full FlexCAT command set per SmartCAT User Guide v4.1.5, with the
exception of ZZPA/ZZPE (panadapter data streaming — out of scope for a
CAT server)
- Two TCP ports by default: 4532 (rigctld) and 5001 (FlexCAT). Up to 6
more ports can be configured/enabled; each port has a companion PTY that
accepts the same commands and responds identically. PTY paths are shown
in the pop-out applet and can be copied to the clipboard with a
right-click — handy when configuring external apps.

## Why CAT in addition to rigctld

Some external apps do not support rigctld, but expect to send TS-2000
CAT commands, with extensions by FlexRadio. AetherSDR now speaks both
protocols, giving operators the flexibility to use whichever their
software requires — setups that currently use SmartCAT can work directly
with AetherSDR without change. TCI is preferred, but this supports both
legacy apps and legacy hams.

## CAT applet redesign

Inspired by SmartSDR for macOS. The space-consuming configuration only
appears when popped out, avoiding clutter of the right panel.

## Test suites

- **`CAT_TS-2000_test`**: 15 sections, 103 checks (92 always-on + 11
PTT/CW gated)
- **`CAT_Flex_test`**: 16 sections, 129 checks (105 always-on + 24
PTT/CW gated)

PTT and CW keyer tests are **skipped by default** to avoid unintended
transmissions. Enable with `--ptt` and `--cw` when a radio is connected
and the operator is ready to transmit.

A firmware TX race was noted during CW testing: the radio briefly
reports TX=0 via CAT while the PA is still hot after CW completes.
Safety watches are added to the test suite; documented as known hardware
behaviour.

## Integration testing

Tested against real hardware (FlexRadio 6500, firmware 4.2.18). Primary
platform: macOS. Also tested on Raspberry Pi 5 / Raspberry Pi OS Trixie.

| App | Connection | Result |
|---|---|---|
| fldigi | TCP + PTY | ✓ |
| WSJT-X | TCP + PTY | ✓ |
| MacLoggerDX | PTY (TS-2000 only) | ✓ |
| N1MM+ | TCP | ✓ (CAT sync; CW keying not possible — see below) |

### N1MM CW keying — known limitation

N1MM keys CW by toggling RTS/DTR on a real serial COM port. Virtual
serial ports (PTYs) are not exposed as COM ports in Windows, so RTS/DTR
keying cannot reach AetherSDR. No workaround exists without a
WinKeyer-compatible keyer emulator. Documented here so operators don't
waste time chasing it.

## Security

Applied the PTY symlink fix (same pattern as GHSA-qxhr-cwrc-pvrm, #3027)
to `CatPort`: per-user symlink directories, atomic rename instead of
unlink+symlink.

## Code quality

**UAF audit:** `SmartCatProtocol` and the new `RigctlProtocol` additions
are both clean — no `[this]` captures in queued lambdas; all dispatch is
synchronous on the main thread.

**ThemeManager:** `CatControlApplet` was included in the Phase 2 mass
migration (#3102). Because this branch replaces the entire applet, that
migration did not carry forward. We applied
`ThemeManager::applyStyleSheet()` throughout — both the docked panel and
the pop-out — so all widgets auto-restyle on `themeChanged`, consistent
with the rest of the codebase. One intentional hardcode remains: the
`:checked` background `#006040` (CAT active state). There is no
`color.background.success` token analogous to `color.background.tx`;
adding one would complete the conversion and is worth proposing as a
follow-up.

Closes #2962

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

…ethersdr#3027)

## Summary

Fixes
[GHSA-qxhr-cwrc-pvrm](GHSA-qxhr-cwrc-pvrm)
— one half of the aethersdr#2940 security audit.

Moves the rigctld convenience symlink out of the shared `/tmp` directory
into a per-user runtime/cache directory, and replaces the non-atomic
`unlink + symlink` sequence with an atomic `symlink + rename` pattern.

## Why

- **Cross-user conflicts**: Two users running AetherSDR on the same
machine fight over `/tmp/AetherSDR-CAT-{A,B,C,D}`. Second user gets
`EEXIST` on `symlink()`, their CAT software can't auto-discover the PTY.
- **TOCTOU on non-sticky `/tmp`**: Rare hardening configs / sandboxed
setups don't apply the sticky bit. The `unlink → symlink` gap allows an
attacker to insert a symlink between the two calls. (Sticky bit + PTY
mode 0620 mitigate on standard systems; this fix removes the
dependency.)
- **Hygiene**: A per-user resource should not live in shared `/tmp`.
Right home is `$XDG_RUNTIME_DIR` (Linux) or `~/Library/Caches/` (macOS).

## What changed

New static `RigctlPty::defaultSymlinkPath(int sliceIndex)`:

| Platform | Path |
|---|---|
| Linux (systemd) | `$XDG_RUNTIME_DIR/aethersdr/cat-{A,B,C,D}` |
| Linux fallback | `$HOME/.cache/aethersdr/cat-{A,B,C,D}` |
| macOS | `$HOME/Library/Caches/AetherSDR/cat-{A,B,C,D}` |

Parent dir created via `mkpath` and tightened to mode 0700 via `chmod`
so a hostile group member can't `readlink()` the PTY path even on shared
systems with shared primary groups.

`RigctlPty::start()`: replaces `unlink + symlink` with
`symlink(slaveName, tmpPath)` + `rename(tmpPath, finalPath)`. `rename()`
is atomic; the temp file is in the same per-user directory so the rename
stays within one filesystem.

UI surfaces updated: `MainWindow` and `CatControlApplet` both call
`RigctlPty::defaultSymlinkPath(i)` instead of hardcoding
`/tmp/AetherSDR-CAT-${letter}`. The displayed path always matches the
actual symlink location.

## Migration impact

**User-visible change**: anyone with WSJT-X / fldigi / etc. configured
to point at `/tmp/AetherSDR-CAT-A` will need to update their CAT
software config to the new per-user path. The displayed path in the CAT
applet shows the new location.

Worth a release-notes mention. Defaulting to the canonical per-user
location going forward — no automatic compatibility symlink at `/tmp`
(would re-introduce the hygiene issue).

## Stats

- 4 files, +98 / −17
- No new dependencies
- No flat-key AppSettings additions (Principle V — N/A, this isn't
settings code)

## Test plan

- [x] Clean build, 0 errors
- [x] Existing test suite passes (18/18)
- [ ] Manual: start AetherSDR, open CAT applet, confirm displayed path
is under `$XDG_RUNTIME_DIR/aethersdr/` or equivalent
- [ ] Manual: verify the symlink actually exists at that path and points
to the PTY slave
- [ ] Manual: re-point CAT software at the new path, confirm commands
flow
- [ ] Manual: stop / restart the PTY, confirm atomic replacement works
(no stale `.tmp` file)
- [ ] Multi-user: two simultaneous AetherSDR instances on the same
machine no longer conflict over the symlink path

## Checklist

- [x] No new flat-key `AppSettings` calls
- [x] All meter UI uses `MeterSmoother` (N/A)
- [x] Documentation will be updated in release notes
- [x] Security-sensitive change references GHSA-qxhr-cwrc-pvrm

Closes aethersdr#2940 (RigctlPty half — VAB half is in flight separately).

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

## Summary

Release prep for v26.5.3 — Aetherial Audio TX completion + security
hardening + 100-commit reliability sweep.

- **CHANGELOG.md** — new v26.5.3 section: 138 commits across 14
contributors since v26.5.2.1
- **README.md** — version line bump 26.5.2.1 → 26.5.3
- **CMakeLists.txt** — already at 26.5.3 (set in aethersdr#3024)

## Highlights

- **Aetherial Audio TX completion** — PAPR all-pass cascade + split-band
DESS, full per-stage CHAIN UI
- **Security advisories** — GHSA-wfx7-w6p8-4jr2 (WAN cert-pin Phase 2,
aethersdr#3026) + GHSA-qxhr-cwrc-pvrm (CAT PTY symlink, aethersdr#3027)
- **MQTT settings dialog refactor** (aethersdr#3051, @s53zo) — JSON-array topics
+ button-event lists, nested-JSON consolidation
- **Audio reliability sweep** — WASAPI silent-open watchdog, mono-only
USB PnP mic recovery, MQTT subscribe diff
- **Native Hamlib NET rigctl** — eliminates external rigctld dependency
- **Stream Deck integration** — Elgato SDK plugin
(Win/Mac/Linux-via-OpenDeck)

## Contributors thanked

@jensenpat (16), @aethersdr-agent (22 bot), @NF0T (12), @rfoust (9),
@Ozy311 (5), @M7HNF-Ian (5), @chibondking (5), @M8WLO (4), @s53zo (2),
@pepefrog1234 (2), @K5PTB (2), @chrisb1964 (1)

## Test plan

- [ ] CI green (build + check-paths + check-windows)
- [ ] CHANGELOG renders correctly on GitHub
- [ ] README version banner shows 26.5.3
- [ ] After merge: tag v26.5.3 once CI green on main

73, Jeremy KK7GWY & Claude (AI dev partner)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

…ethersdr#3131)

## CAT Protocol Coverage

- Full Kenwood TS-2000 command set, referencing the manual appendix,
except commands not applicable to a FlexRadio
- Full FlexCAT command set per SmartCAT User Guide v4.1.5, with the
exception of ZZPA/ZZPE (panadapter data streaming — out of scope for a
CAT server)
- Two TCP ports by default: 4532 (rigctld) and 5001 (FlexCAT). Up to 6
more ports can be configured/enabled; each port has a companion PTY that
accepts the same commands and responds identically. PTY paths are shown
in the pop-out applet and can be copied to the clipboard with a
right-click — handy when configuring external apps.

## Why CAT in addition to rigctld

Some external apps do not support rigctld, but expect to send TS-2000
CAT commands, with extensions by FlexRadio. AetherSDR now speaks both
protocols, giving operators the flexibility to use whichever their
software requires — setups that currently use SmartCAT can work directly
with AetherSDR without change. TCI is preferred, but this supports both
legacy apps and legacy hams.

## CAT applet redesign

Inspired by SmartSDR for macOS. The space-consuming configuration only
appears when popped out, avoiding clutter of the right panel.

## Test suites

- **`CAT_TS-2000_test`**: 15 sections, 103 checks (92 always-on + 11
PTT/CW gated)
- **`CAT_Flex_test`**: 16 sections, 129 checks (105 always-on + 24
PTT/CW gated)

PTT and CW keyer tests are **skipped by default** to avoid unintended
transmissions. Enable with `--ptt` and `--cw` when a radio is connected
and the operator is ready to transmit.

A firmware TX race was noted during CW testing: the radio briefly
reports TX=0 via CAT while the PA is still hot after CW completes.
Safety watches are added to the test suite; documented as known hardware
behaviour.

## Integration testing

Tested against real hardware (FlexRadio 6500, firmware 4.2.18). Primary
platform: macOS. Also tested on Raspberry Pi 5 / Raspberry Pi OS Trixie.

| App | Connection | Result |
|---|---|---|
| fldigi | TCP + PTY | ✓ |
| WSJT-X | TCP + PTY | ✓ |
| MacLoggerDX | PTY (TS-2000 only) | ✓ |
| N1MM+ | TCP | ✓ (CAT sync; CW keying not possible — see below) |

### N1MM CW keying — known limitation

N1MM keys CW by toggling RTS/DTR on a real serial COM port. Virtual
serial ports (PTYs) are not exposed as COM ports in Windows, so RTS/DTR
keying cannot reach AetherSDR. No workaround exists without a
WinKeyer-compatible keyer emulator. Documented here so operators don't
waste time chasing it.

## Security

Applied the PTY symlink fix (same pattern as GHSA-qxhr-cwrc-pvrm, aethersdr#3027)
to `CatPort`: per-user symlink directories, atomic rename instead of
unlink+symlink.

## Code quality

**UAF audit:** `SmartCatProtocol` and the new `RigctlProtocol` additions
are both clean — no `[this]` captures in queued lambdas; all dispatch is
synchronous on the main thread.

**ThemeManager:** `CatControlApplet` was included in the Phase 2 mass
migration (aethersdr#3102). Because this branch replaces the entire applet, that
migration did not carry forward. We applied
`ThemeManager::applyStyleSheet()` throughout — both the docked panel and
the pop-out — so all widgets auto-restyle on `themeChanged`, consistent
with the rest of the codebase. One intentional hardcode remains: the
`:checked` background `#006040` (CAT active state). There is no
`color.background.success` token analogous to `color.background.tx`;
adding one would complete the conversion and is worth proposing as a
follow-up.

Closes aethersdr#2962

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>