Files
DECNET/decnet/templates/mysql/server.py
anti 6708f26e6b fix(packaging): move templates/ into decnet/ package so they ship with pip install
The docker build contexts and syslog_bridge.py lived at repo root, which
meant setuptools (include = ["decnet*"]) never shipped them. Agents
installed via `pip install $RELEASE_DIR` got site-packages/decnet/** but no
templates/, so every deploy blew up in deployer._sync_logging_helper with
FileNotFoundError on templates/syslog_bridge.py.

Move templates/ -> decnet/templates/ and declare it as setuptools
package-data. Path resolutions in services/*.py and engine/deployer.py drop
one .parent since templates now lives beside the code. Test fixtures,
bandit exclude path, and coverage omit glob updated to match.
2026-04-19 19:30:04 -04:00

112 lines
4.1 KiB
Python

#!/usr/bin/env python3
"""
MySQLserver.
Sends a realistic MySQL 5.7 server handshake, reads the client login
packet, extracts username, then closes with Access Denied. Logs auth
attempts as JSON.
"""
import asyncio
import os
import struct
from syslog_bridge import syslog_line, write_syslog_file, forward_syslog
NODE_NAME = os.environ.get("NODE_NAME", "dbserver")
SERVICE_NAME = "mysql"
LOG_TARGET = os.environ.get("LOG_TARGET", "")
PORT = int(os.environ.get("PORT", "3306"))
_MYSQL_VER = os.environ.get("MYSQL_VERSION", "5.7.38-log")
# Minimal MySQL server greeting (protocol v10) — version string is configurable
_GREETING = (
b"\x0a" # protocol version 10
+ _MYSQL_VER.encode() + b"\x00" # server version + NUL
+ b"\x01\x00\x00\x00" # connection id = 1
+ b"\x70\x76\x21\x6d\x61\x67\x69\x63" # auth-plugin-data part 1
+ b"\x00" # filler
+ b"\xff\xf7" # capability flags low
+ b"\x21" # charset utf8
+ b"\x02\x00" # status flags
+ b"\xff\x81" # capability flags high
+ b"\x15" # auth plugin data length
+ b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" # reserved (10 bytes)
+ b"\x21\x4f\x7d\x25\x3e\x55\x4d\x7c\x67\x75\x5e\x31\x00" # auth part 2
+ b"mysql_native_password\x00" # auth plugin name
)
def _make_packet(payload: bytes, seq: int = 0) -> bytes:
length = len(payload)
return struct.pack("<I", length)[:3] + bytes([seq]) + payload
def _log(event_type: str, severity: int = 6, **kwargs) -> None:
line = syslog_line(SERVICE_NAME, NODE_NAME, event_type, severity, **kwargs)
write_syslog_file(line)
forward_syslog(line, LOG_TARGET)
class MySQLProtocol(asyncio.Protocol):
def __init__(self):
self._transport = None
self._peer = None
self._buf = b""
self._greeted = False
def connection_made(self, transport):
self._transport = transport
self._peer = transport.get_extra_info("peername", ("?", 0))
_log("connect", src=self._peer[0], src_port=self._peer[1])
transport.write(_make_packet(_GREETING, seq=0))
self._greeted = True
def data_received(self, data):
self._buf += data
# MySQL packets: 3-byte length + 1-byte seq + payload
while len(self._buf) >= 4:
length = struct.unpack("<I", self._buf[:3] + b"\x00")[0]
if length > 1024 * 1024:
self._transport.close()
self._buf = b""
return
if len(self._buf) < 4 + length:
break
payload = self._buf[4:4 + length]
self._buf = self._buf[4 + length:]
self._handle_packet(payload)
def _handle_packet(self, payload: bytes):
if not payload:
return
# Login packet: capability flags (4), max_packet (4), charset (1), reserved (23), username (NUL-terminated)
if len(payload) > 32:
try:
# skip capability(4) + max_pkt(4) + charset(1) + reserved(23) = 32 bytes
username_start = 32
nul = payload.index(b"\x00", username_start)
username = payload[username_start:nul].decode(errors="replace")
except (ValueError, IndexError):
username = "<parse_error>"
_log("auth", src=self._peer[0], username=username)
# Send Access Denied error
err = b"\xff" + struct.pack("<H", 1045) + b"#28000Access denied for user\x00"
self._transport.write(_make_packet(err, seq=2))
self._transport.close()
def connection_lost(self, exc):
_log("disconnect", src=self._peer[0] if self._peer else "?")
async def main():
_log("startup", msg=f"MySQL server starting as {NODE_NAME}")
loop = asyncio.get_running_loop()
server = await loop.create_server(MySQLProtocol, "0.0.0.0", PORT) # nosec B104
async with server:
await server.serve_forever()
if __name__ == "__main__":
asyncio.run(main())