serversdown/seismo-relay
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

fix: validate offset size in build_bw_frame and adjust payload construction

Browse Source
This commit is contained in:
Brian Harrison
2026-04-01 13:28:00 -04:00
parent 7e501620fc
commit 824322597a
1 changed files with 9 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
minimateplus/framing.py
View File

@@ -120,7 +120,15 @@ def build_bw_frame(sub: int, offset: int = 0, params: bytes = bytes(10)) -> byte
""" """
if len(params) != 10: if len(params) != 10:
raise ValueError(f"params must be exactly 10 bytes, got {len(params)}") raise ValueError(f"params must be exactly 10 bytes, got {len(params)}")
payload = bytes([BW_CMD, 0x00, sub, 0x00, 0x00, offset]) + params if offset > 0xFFFF:
raise ValueError(f"offset must fit in uint16, got {offset:#06x}")
# offset is a uint16 split across bytes [4] (high) and [5] (low).
# For all standard reads (offset ≤ 0xFF), byte[4] = 0x00 — consistent with
# every captured BW frame. For large payloads (e.g. SUB 1A / E5 at 0x082A),
# byte[4] carries the high byte. 🔶 INFERRED — confirm once E5 is captured.
offset_hi = (offset >> 8) & 0xFF
offset_lo = offset & 0xFF
payload = bytes([BW_CMD, 0x00, sub, 0x00, offset_hi, offset_lo]) + params
chk = checksum(payload) chk = checksum(payload)
wire = bytes([ACK, STX]) + dle_stuff(payload + bytes([chk])) + bytes([ETX]) wire = bytes([ACK, STX]) + dle_stuff(payload + bytes([chk])) + bytes([ETX])
return wire return wire