Iter 6. Connects the typed payload parser (iter 5) to the framed
wire format (iter 4): the CRC32 now covers the section-prefixed
payload bytes per ADR-119 §2.2 ("CRC32 covers all section bytes
including length prefixes").
Added:
- BfldFrame::from_payload(header, &BfldPayload) -> Self
Auto-syncs header.flags HAS_CSI_DELTA bit from payload.csi_delta.is_some(),
serializes payload via to_bytes(), feeds BfldFrame::new() which computes
payload_len + payload_crc32 over the section-prefixed bytes.
- BfldFrame::parse_payload(&self) -> Result<BfldPayload, BfldError>
Reads HAS_CSI_DELTA bit from header.flags and dispatches to
BfldPayload::from_bytes(&self.payload, expect_csi_delta).
tests/frame_payload_integration.rs (7 named tests, all green):
from_payload_then_parse_payload_is_identity
from_payload_autosets_has_csi_delta_flag
from_payload_clears_has_csi_delta_flag_when_csi_absent
(verifies the flag is cleared when csi_delta is None even if caller
pre-set the bit; other flag bits like PRIVACY_MODE are preserved)
frame_crc_covers_section_prefixed_bytes
(mutating a byte inside section body trips CRC, not magic/length)
frame_crc_covers_section_length_prefixes
(mutating a section length-prefix byte trips CRC before parser ever runs)
empty_typed_payload_roundtrips
end_to_end_wire_roundtrip_via_bytes
(BfldPayload -> from_payload -> to_bytes -> from_bytes -> parse_payload
is the identity function modulo flag auto-set)
ACs progressed:
- AC5 ↑ — full payload round-trip through the framed bytes (closes
the round-trip leg from BfldPayload through wire and back).
- AC6 ↑ — same input produces same bytes through both layers.
- AC4 ↑ — CRC mismatch on tampered section bodies and tampered section
length prefixes both surface as BfldError::Crc, not as silent acceptance
or as a deeper parser error.
Test config:
- cargo test --no-default-features → 17 passed (integration tests cfg-out)
- cargo test → 39 passed (3 + 6 + 7 + 8 + 8 + 7)
Out of scope (next iter target):
- PrivacyGate::demote(frame, target_class) — ADR-120 §2.4 class transition
transformer with subtle::Zeroize on dropped fields.
- IdentityEmbedding newtype with no Serialize impl (ADR-120 §2.5 / I2).
Co-Authored-By: claude-flow <ruv@ruv.net>
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