feat(adr-118/p1.4): BfldFrame (header + payload + CRC32) — 24/24 GREEN
Iter 4. Lands the central wire-format primitive: complete frames with
header + arbitrary-length payload, protected by CRC-32/ISO-HDLC.
Added:
- crc = "3" dependency (CRC-32/ISO-HDLC, same poly as Ethernet / zlib)
- src/frame.rs: CRC32_ALG const and crc32_of_payload(&[u8]) -> u32
- src/frame.rs: BfldFrame { header, payload: Vec<u8> } (gated on `std`)
* BfldFrame::new(header, payload) — auto-syncs payload_len + payload_crc32
* BfldFrame::to_bytes() -> Vec<u8> — header LE bytes ‖ payload
* BfldFrame::from_bytes(&[u8]) -> Result<Self, BfldError>
- BfldError::TruncatedFrame { got, need } variant
- Doc strings on BfldError::Crc and BfldError::PrivacyViolation field names
- tests/frame_roundtrip.rs (7 named tests, gated on feature = "std"):
frame_roundtrip_preserves_header_and_payload
frame_new_syncs_payload_len_and_crc
frame_serialization_is_deterministic
frame_rejects_payload_crc_mismatch
frame_rejects_truncated_buffer_smaller_than_header
frame_rejects_truncated_buffer_smaller_than_payload
empty_payload_is_valid (CRC of empty payload is 0x00000000)
Test config:
- cargo test --no-default-features → 17 passed (frame_roundtrip cfg-out)
- cargo test (default features = std) → 24 passed (3+6+7+8)
ADR-119 ACs progressed:
- AC4 partial: bad-magic + bad-version + CRC-mismatch + truncation rejected
with typed errors; field-level masking lives in the privacy_gate iter.
- AC5: BfldFrame round-trip preserves header + payload + CRC.
- AC6: Identical inputs produce bit-identical bytes (asserted explicitly).
Out of scope (next iter):
- Payload section parser (compressed_angle_matrix, amplitude_proxy, ...)
— only the byte buffer is opaque so far; sections need length prefixes.
- BfldFrameRef<'_> for ESP32-S3 self-only mode (no-alloc, ADR-123 §2.5).
- PrivacyGate::demote(frame, target_class) transformer (ADR-120 §2.4).
Co-Authored-By: claude-flow <ruv@ruv.net>
775661b2e8