Golden manifest tests: layout closure + per-blob goldens (wm/wa/patch), make test

Makefile

@@ -2,7 +2,7 @@ BLOBS ?= $(wildcard /lib/firmware/mediatek/mt79*_wm.bin) \
         $(wildcard /lib/firmware/mediatek/mt79*_wa.bin) \
         $(wildcard /lib/firmware/mediatek/mt79*_rom_patch.bin)
 
-.PHONY: help extract
+.PHONY: help extract test
 
 help:
 	@echo "make extract  - carve all MediaTek Connac2 blobs found on this host"
@@ -10,3 +10,6 @@ help:
 
 extract:
 	python3 tools/mtk_fw_extract.py $(BLOBS)
+
+test:
+	python3 -m unittest discover -s tests -v

docs/findings.md

@@ -66,6 +66,10 @@ patch sections: `enc_type == 0` (plaintext).
 Evidence: `mt76_connac2_load_patch()` + `struct mt76_connac2_patch_hdr/_sec`
 in `mt76_connac_mcu.h`; exact parse of 4 patch blobs.
 
+Section counts: mt7915 patch = 2 sections, all others = 1; section `type`
+constant `0x30002` on every observed section (loader downloads all sections
+regardless; field semantics otherwise unobserved).
+
 ## Unknowns registry
 
 - **U1 — `feature_set` bit 7 (0x80):** observed only on WM regions at

tests/test_extract.py

@@ -0,0 +1,105 @@
+"""Golden-manifest tests for the Connac2 container extractor.
+
+Runs against whatever MediaTek blobs exist on this host (skip otherwise).
+Golden values observed from linux-firmware snapshot 2026-04-20; when a value
+here fails against a newer snapshot, the blob changed — update the golden
+value *and* note it in the changelog, don't silently absorb it.
+"""
+import subprocess
+import sys
+import unittest
+from pathlib import Path
+
+REPO = Path(__file__).resolve().parent.parent
+FW = Path('/lib/firmware/mediatek')
+
+# filename -> (chip_id, eco, n_region, hidden_trailer_string_or_None)
+GOLDEN_WM = {
+    'mt7981_wm.bin': (0x14, 0, 11,
+                      't-neptune-main-mt7915-1953-MT7981_MP2111_IMP-20240823161204'),
+    'mt7986_wm.bin': (0x0f, 0, 11,
+                      't-neptune-main-mt7915-1953-MT7986_MP2111_IMP-20240823160608'),
+    'mt7916_wm.bin': (0x13, 0, 9,
+                      't-neptune-main-mt7915-1953-MT7916_MP2111_IMP-20240823170147'),
+    'mt7915_wm.bin': (0x0b, 1, 7,
+                      't-neptune-mp-mt7915-2045-MT7915_MP_7_4_2045-20220929103802'),
+}
+GOLDEN_WA = {
+    'mt7981_wa.bin': (0x00, 0, 3, None),
+    'mt7986_wa.bin': (0x00, 0, 3, None),
+    'mt7916_wa.bin': (0x00, 0, 3, None),
+    'mt7915_wa.bin': (0x00, 1, 3, None),
+}
+
+
+def parse(path: Path, out: Path) -> dict:
+    out.mkdir(parents=True, exist_ok=True)
+    sys.path.insert(0, str(REPO / 'tools'))
+    import mtk_fw_extract as x
+    return (x.carve_patch if 'patch' in path.name else x.carve_ram)(path, out)
+
+
+class LayoutClosure(unittest.TestCase):
+    """sum(region.len) + hidden trailer + table + trailer == file size."""
+
+    def test_closure(self):
+        blobs = sorted(FW.glob('mt79*_wm.bin')) + sorted(FW.glob('mt79*_wa.bin'))
+        if not blobs:
+            self.skipTest('no mediatek blobs on this host')
+        import struct
+        T = struct.Struct('<5B2s10s15sI')
+        R = struct.Struct('<III4sIIBB14s')
+        for p in blobs:
+            with self.subTest(blob=p.name):
+                d = p.read_bytes()
+                n = d[len(d) - T.size + 2]
+                tbl = len(d) - T.size - n * R.size
+                data_end = sum(R.unpack_from(d, tbl + i * R.size)[5]
+                               for i in range(n))
+                self.assertEqual(
+                    data_end + (tbl - data_end) + n * R.size + T.size, len(d),
+                    'layout does not close')
+
+
+class GoldenRAM(unittest.TestCase):
+
+    def run_one(self, name, golden, outdir):
+        p = FW / name
+        if not p.exists():
+            self.skipTest(f'{name} not present')
+        info = parse(p, outdir)
+        chip, eco, n, hidden = golden
+        self.assertEqual(info['chip_id'], chip, name)
+        self.assertEqual(info['eco'], eco, name)
+        self.assertEqual(info['n_region'], n, name)
+        ht = info.get('hidden_trailer', {})
+        self.assertEqual(ht.get('string'), hidden, name)
+
+    def test_wm(self):
+        for name, golden in GOLDEN_WM.items():
+            with self.subTest(blob=name):
+                self.run_one(name, golden, REPO / 'extracted' / 'test_wm')
+
+    def test_wa(self):
+        for name, golden in GOLDEN_WA.items():
+            with self.subTest(blob=name):
+                self.run_one(name, golden, REPO / 'extracted' / 'test_wa')
+
+
+class GoldenPatch(unittest.TestCase):
+
+    def test_patch(self):
+        golden = {'mt7981_rom_patch.bin': 1, 'mt7986_rom_patch.bin': 1,
+                  'mt7916_rom_patch.bin': 1, 'mt7915_rom_patch.bin': 2}
+        for p in sorted(FW.glob('mt79*_rom_patch.bin')):
+            with self.subTest(blob=p.name):
+                info = parse(p, REPO / 'extracted' / 'test_patch')
+                self.assertEqual(info['platform'], 'ALPS')
+                self.assertEqual(info['n_region'], golden[p.name])
+                for sec in info['sections']:
+                    self.assertEqual(sec['type'], '0x30002')
+                    self.assertEqual(sec['enc_type'], 0)  # plaintext (F4)
+
+
+if __name__ == '__main__':
+    unittest.main(verbosity=2)