Socket-transport cmd space (off_14 ids) from live capture: 1101/1307/1705/1707 + host_probe3

scripts/host_probe3.py

@@ -0,0 +1,144 @@
+#!/usr/bin/env python3
+"""Host probe v3 — socket-transport command ids (stdlib only).
+
+A PCAPdroid capture of the working app showed ``{"cmdType":1101, ...}`` on
+the wire: ``CommunicationCmd::cmd`` returns the *second* id field for
+socket mode (QUERY_DEVICE_INFO 1101, APOWER 1307, BMS 1705, EMS 1707).
+Earlier probes used the small ids (25/0/29/30) and were dropped silently.
+
+Run on the SoftAP-joined host:
+    python3 host_probe3.py --sn A03X2516013210060005 --ports 9000
+"""
+
+import argparse
+import json
+import socket
+import time
+import zlib
+
+# Wire cmdType per CommunicationCmd::cmd (socket mode).
+APOWER, QUERY_INFO, BMS, EMS = 0x51B, 0x44D, 0x6A9, 0x6AB
+SNNO = [0]
+
+
+def secret_key(sn):
+    return format(sum(sn.encode()) & 0xFF, "x")
+
+
+def build_envelope(sn, cmd, data=None, snno=None, ts=None, equip=None):
+    SNNO[0] = (SNNO[0] % 9999) + 1
+    env = {"cmdType": cmd, "equipNo": equip if equip is not None else sn,
+           "type": 0,
+           "timeStamp": ts if ts is not None else int(time.time()),
+           "snno": snno if snno is not None else SNNO[0], "len": 0, "crc": ""}
+    if data:
+        compact = json.dumps(data, separators=(",", ":"))
+        env["len"] = len(compact.encode())
+        env["crc"] = format(zlib.crc32(compact.encode()), "X")
+        env["dataArea"] = data
+    return json.dumps(env, separators=(",", ":"))
+
+
+def encrypt(json_str, key):
+    parts = json_str.split(",")
+    a = (parts[0] + "," + parts[1] + ",").encode()
+    b = ",".join(parts[2:]).encode()
+    n = int(key, 32)
+    return a + bytes((b[i] + i + len(a) + n) & 0xFF
+                     for i in range(len(b)))
+
+
+def decrypt_data(wire, radix=32):
+    try:
+        i = wire.find(b"\x58")
+        if i < 0:
+            return ""
+        j = wire.find(b"\x58", i + 1)
+        if j < 0:
+            return ""
+        s = wire[:j].decode()
+        probe = json.loads(s + "}")
+        if not isinstance(probe, dict):
+            return ""
+        n = int(secret_key(str(probe.get("equipNo", ""))), radix)
+        prefix = s + ","
+        tail = wire[j + 1:]
+        pl = len(prefix.encode())
+        plain = bytes((t - k - pl - n) & 0xFF for k, t in enumerate(tail))
+        return prefix + plain.decode()
+    except Exception:
+        return ""
+
+
+def recv_all(sock, idle=6.0):
+    out = bytearray()
+    sock.settimeout(idle)
+    while True:
+        try:
+            chunk = sock.recv(65536)
+        except (socket.timeout, TimeoutError):
+            break
+        if not chunk:
+            break
+        out.extend(chunk)
+    return bytes(out)
+
+
+def run(label, host, port, tx, timeout, pre_read=0.0):
+    rx_pre, rx, err, reply = b"", b"", None, None
+    try:
+        with socket.create_connection((host, port),
+                                      timeout=timeout) as sock:
+            if pre_read:
+                rx_pre = recv_all(sock, idle=pre_read)
+            if tx:
+                sock.sendall(tx)
+                rx = recv_all(sock)
+            if rx:
+                dec = decrypt_data(rx)
+                reply = json.loads(dec) if dec else {"_raw": rx.hex()}
+    except (ConnectionError, socket.error, TimeoutError) as exc:
+        err = "%s: %s" % (type(exc).__name__, exc)
+    print("--- %s -> %s:%d" % (label, host, port))
+    print("  tx (%d B): %s" % (len(tx), tx.hex() or "(none)"))
+    if rx_pre:
+        print("  rx_pre (%d B): %s" % (len(rx_pre), rx_pre.hex()))
+    print("  rx (%d B): %s" % (len(rx), rx.hex() or "(empty)"))
+    if reply is not None:
+        print("  reply: " + json.dumps(reply, default=str)[:2000])
+    if err:
+        print("  error: %s" % err)
+    return rx
+
+
+def main():
+    ap = argparse.ArgumentParser()
+    ap.add_argument("--sn", required=True)
+    ap.add_argument("--host", default="10.100.1.1")
+    ap.add_argument("--ports", default="9000")
+    ap.add_argument("--timeout", type=float, default=5.0)
+    args = ap.parse_args()
+    key = secret_key(args.sn)
+    print("secret key for %s: %s (radix 32)" % (args.sn, key))
+    variants = [
+        ("queryInfo/1101+SN", QUERY_INFO, None, None),
+        ("queryInfo/1101+empty-SN", QUERY_INFO, None, ""),
+        ("apower/1307+update2", APOWER, {"update": 2}, None),
+        ("apower/1307+none", APOWER, None, None),
+        ("bms/1705", BMS, None, None),
+        ("ems/1707", EMS, None, None),
+    ]
+    for port in [int(p) for p in args.ports.split(",") if p.strip()]:
+        for label, cmd, data, equip in variants:
+            tx = encrypt(build_envelope(
+                args.sn, cmd, data,
+                equip=args.sn if equip is None else equip or "00000000",
+            ), key)
+            if run(label, args.host, port, tx, args.timeout,
+                   pre_read=4.0 if label.startswith("queryInfo/1101+SN")
+                   else 0.0):
+                return
+
+
+if __name__ == "__main__":
+    main()