Commit Graph
2 Commits
Author SHA1 Message Date
1e982fa78c Sign plaintext packets in licensed mode (#10969)
* feat: sign licensed plaintext packets

Preserve and publish identity keys in licensed mode so existing XEdDSA signatures can authenticate plaintext traffic. Sign licensed broadcasts and direct messages when they fit, while keeping PKI encryption disabled and normal routing behavior unchanged.

* fix(security): persist licensed channel sanitation

* fix(security): close licensed migration lifecycle gaps

* fix(security): address licensed signing review feedback

* test: restore signing globals from Unity teardown

* fix(baseui): allow confirmed ham region selection

* fix(baseui): guard region picker validation

* style: trunk fmt

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Co-authored-by: Ben Meadors <benmmeadors@gmail.com>
Co-authored-by: Austin <vidplace7@gmail.com>
2026-07-27 02:57:15 +00:00
d846780a9b More fuzz tests and small fixes for the findings (#10864)
* first pass tests

* more tests

* Fix two crafted-admin-packet crashes found by the E5 fuzzer

Both are reachable from an authorized admin (local from==0, admin channel,
or PKC) - remote DoS:

1. SIGFPE in LoRa config validation. A set_config LoRaConfig with
   use_preset=false and bandwidth=0 makes freqSlotWidth 0, so numFreqSlots
   is 0 and `hash(name) % numFreqSlots` (RadioInterface.cpp) divides by
   zero. Guard the modulo; the existing channel_num check then rejects/
   clamps the config.

2. Stack overflow in Channels::getKey. A SECONDARY channel at the primary
   slot with an empty PSK recursed into getKey(primaryIndex) forever. Skip
   the primary-key borrow when chIndex == primaryIndex.

Re-enable the E5 admin fuzzer to hit both triggers again (use_preset both
ways incl. bandwidth 0, plus the set_channel tag) as regression guards.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* Correct fuzz-test invariants after the crash fixes

- E5 admin fuzz: node eviction under a filling NodeDB is legitimate, so
  assert only the bounded-count invariant, not that a specific seed node
  survives 6000 mutating ops.
- TMM blitz: scope off the nodeinfo direct-response send path (it needs a
  fully-wired MeshService/phone queue the fixture doesn't provide; the
  deterministic directResponse tests cover it). The crafted-nodenum
  rate/unknown/position cache stress is unchanged.

clod helped too

* realistic tests

* test: dedup fuzz RNG into shared test/support/DeterministicRng.h

The four in-tree fuzz suites (test_fuzz_decode, test_fuzz_packets,
test_hop_scaling, test_traffic_management) each carried a byte-identical
copy of the seeded 64-bit LCG (rngSeed/rngNext/rngByte/rngRange). Hoist
it into one shared header so there is a single generator to reason about
and no risk of the copies drifting. static inline keeps per-suite state
per translation unit and avoids -Wunused-function for suites that don't
use every helper. Also corrects a stale comment in test_traffic_management
(the blitz's nodeinfo direct-response path is intentionally left off).

No behavioral change: same constants, same per-suite seeds.

clod helped too

* test: fuzz uncovered ProtobufModule handlers and the MQTT downlink ingress

Extend the in-tree fuzz coverage to packet sources that previously had
none:

- test_fuzz_packets E8/E9/E10: drive PositionModule, DeviceTelemetryModule
  and NeighborInfoModule at handleReceivedProtobuf directly (via using-shims,
  bypassing the ProtobufModule reply/send path so no router is needed). The
  fixture already stands up nodeDB/service/channels, and nodeStatus/powerStatus
  are auto-initialized in main.cpp, so no new globals are required. Adds a
  shared fuzzRxHeader() helper for crafting adversarial RX packet headers.
- test_fuzz_decode: add meshtastic_KeyVerification to the decode table. The
  KeyVerification and StoreForward handler paths are documented as decode-level
  only, with the concrete reason each is intrinsic (private-state gating /
  PSRAM + self-pointer wiring), not a fixture gap.
- test_mqtt: test_receiveFuzzServiceEnvelope blitzes the non-RF broker-push
  ingress (onReceiveProto) two ways - raw garbage bytes that must fail envelope
  decode cleanly, and a well-formed ServiceEnvelope wrapping a crafted inner
  MeshPacket over crafted channel_id/gateway_id - exercising the channel match,
  isFromUs, XEdDSA receive policy and perhapsDecode chain. Adds a deliverRaw()
  passthrough to MQTTUnitTest.

All under the coverage env (ASan/LSan). No firmware/src changes. Full sweep
GREEN 27/27, 544 cases.

clod helped too

* Harden LoRa/channel config against crafted admin messages; consolidate test helpers

Production (review findings on the hot-fuzz crash fixes):
- Clamp bandwidth at the source (clampBandwidthKHz) in checkOrClampConfigLora
  and applyModemConfig so numFreqSlots can never be 0 for any consumer; a
  bandwidth-0 set_config previously passed validation and re-armed the SIGFPE
  on the next applyModemConfig.
- Guard applyModemConfig's hash % numFreqSlots (the validator's sibling modulo
  was fixed earlier but this one was still unguarded).
- Enforce the primary-channel invariant in Channels::onConfigChanged: a config
  demoting every slot now re-promotes the stale SECONDARY slot (keeping its
  key) or restores the default channel if the slot is DISABLED, instead of
  leaving every getPrimaryIndex() reader on a non-primary slot. The getKey
  recursion guard stays as defense-in-depth.

Tests:
- New test/support/MockMeshService.h and AdminModuleTestShim.h replace four
  byte-identical mocks and three divergent admin shims (test_mqtt's capturing
  mock is genuinely different and stays).
- DeterministicRng.h: add rngFill() (replaces 14 hand-rolled fill loops) and
  rngEdgeNodeNum() (unifies the three NodeNum boundary pools).
- Extract fuzzChannelSettings() shared by the set_channel case and fuzzBeacon.
- fuzzBeacon: the un-terminated branch now fills the whole buffer with non-NUL
  bytes so the strnlen bound is actually stressed (~50% of iterations, not ~4%).
- E6 beacon fuzz: replace the TEST_ASSERT_TRUE(true) tautology with real
  invariants (handler never consumes; offers land in lastReceivedOffer keyed
  to the sender).
- Trim the seven over-long comment blocks flagged against the 1-2 line rule;
  the FINDINGS trailer moves to this commit message (see production notes).

Full native suite GREEN 27/27 under the coverage (ASan/LSan) env.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* Clamp UTF-8 char length in the emote walkers; add test_fuzz_emotes

A TEXT_MESSAGE payload is opaque protobuf bytes, so PB_VALIDATE_UTF8 never
screens it - invalid UTF-8 and truncated multi-byte lead bytes reach the
emote/width render path verbatim. EmoteRenderer's walkers advanced by
utf8CharLen(lead) without clamping to the bytes actually remaining, so a
truncated lead (e.g. a lone 0xF0, which claims 4 bytes) near the end of the
buffer made getUtf8ChunkWidth's memcpy read past the string. ASan confirms a
heap-buffer-overflow READ from measureStringWithEmotes.

Add utf8CharLenClamped() and use it at every walk site (width measure,
truncation cut-loop, and the draw-path text-run/chunk builders); the one
already-guarded site (matchAtIgnoringModifiers) is unchanged.

New test/test_fuzz_emotes drives measureStringWithEmotes and truncateToWidth
over adversarial byte strings (biased to embed/end in truncated multi-byte
leads) in exact-sized heap buffers so any over-read is a hard ASan fault. Its
headless display uses a synthetic font (firstChar 0, fontData centered in a
large buffer) so the stock OLEDDisplay::getStringWidth - which indexes the
font jump table with a signed char and over-reads for any byte >= 0x80 - does
not mask the finding. native-suite-count bumped 27 -> 28.

Full native suite GREEN 28/28 under the coverage (ASan/LSan) env.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* Keep emote width measurement in-bounds for non-ASCII bytes

OLEDDisplay::getStringWidth (the utf8=false path EmoteRenderer uses on default
builds) indexes the font jump table by (c - firstChar) with a signed char and
no bounds check, so any byte outside printable ASCII - high bytes from UTF-8
text, but also a stray control byte like 0x0A - reads outside the font array.
On-device this reads adjacent flash and returns a garbage width; under ASan the
test_fuzz_emotes fuzzer flags it as a global-buffer-overflow, and it made the
non-ASCII width measurement meaningless either way.

The OLED driver is a pinned upstream dependency, so guard it firmware-side in
EmoteRenderer's getStringWidth helper: measure a sanitized copy where any byte
outside [0x20, 0x7E] counts as a '?' placeholder. Printable ASCII is unchanged
and the UA/RU lookup path is untouched.

test_fuzz_emotes now drives a real ArialMT font instead of the synthetic
in-bounds font it needed before this fix, so the suite exercises the true
production width path (utf8CharLen clamp + this sanitizer) end to end. The same
fuzzer tripped the global-buffer-overflow before this change.

Full native suite GREEN 28/28 under the coverage (ASan/LSan) env.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

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Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
2026-07-06 13:19:01 -05:00