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mirror of git://sourceware.org/git/lvm2.git synced 2024-12-22 17:35:59 +03:00
lvm2/test/dbus/lvm_error_inject.py
Tony Asleson 9c3b91a513 lvmdbustest: Shutdown cleanly with "exit"
Make the error injection wrapper handle the exit case, so that we can
clean up gracefully when instructed to do so.
2023-03-10 12:51:53 -06:00

345 lines
11 KiB
Python
Executable File

#!/usr/bin/python3
# Simulate errors by doing the following for both lvm and lvm shell:
# Randomly return
# - Bad exit code
# - Exit code 5 (exported VG)
# - Truncated JSON
# - Missing key in JSON
#
# This is done by sitting between lvm dbusd and lvm. If running via systemd, add the following to the service file
# Environment="LVM_BINARY=/path/to/this file/lvm2/test/dbus/lvm_error_inject.py"
# systemctl daemon-reload
# systemctl restart lvm2-lvmdbusd
import copy
import json
import multiprocessing
import os
import pty
import random
import select
import signal
import string
import subprocess
import sys
import tempfile
import traceback
from collections import deque
from fcntl import fcntl, F_GETFL, F_SETFL
from subprocess import Popen
CS = string.ascii_letters + "\n\t " + string.digits
run = multiprocessing.Value('i', 1)
SH = None
def rs(length, character_set=CS):
return ''.join(random.choice(character_set) for _ in range(length))
RS = rs(512)
d_out = open("/tmp/mitm_lvm.txt", "a")
def debug(msg):
m = str(msg)
d_out.write(m)
if m[-1] != "\n":
d_out.write("\n")
d_out.flush()
# Make stream non-blocking
def make_non_block(stream):
flags = fcntl(stream, F_GETFL)
fcntl(stream, F_SETFL, flags | os.O_NONBLOCK)
def read_decoded(stream):
tmp = stream.read()
if tmp:
return tmp.decode("utf-8")
return ''
def write_some(q, stream, remaining=False, binary=False):
if len(q) > 0:
if remaining:
to_send = len(q)
else:
to_send = random.randint(1, len(q))
for _ in range(0, to_send):
c = q.popleft()
if binary:
stream.write(bytes(c, "utf-8"))
else:
stream.write(c)
stream.flush()
def del_random_key(src_dict):
keys = list(src_dict.keys())
pick = random.randint(0, len(keys) - 1)
debug("%s will be deleted" % keys[pick])
del src_dict[keys[pick]]
def inject_key_error(output_json):
debug("Deleting a key")
for r in output_json['report']:
if 'lv' in r:
for i in r['lv']:
debug("deleting a lv key")
del_random_key(i)
return
if 'vg' in r:
for i in r["vg"]:
debug("deleting a vg key")
del_random_key(i)
return
elif 'pv' in r:
for i in r["pv"]:
debug("deleting a pv key")
del_random_key(i)
return
def inject_exit_error(output_json, val):
if 'log' in output_json and len(output_json['log']) > 0:
debug("Returning bad exit code")
# Change the exit code to failure
output_json['log'][-1:][0]['log_ret_code'] = "%d" % val
else:
# We are in fork & exec mode, just exit.
if val == 0:
sys.exit(1)
sys.exit(val)
def inject_error(output_str, output_json=None):
try:
if random.randint(0, 9) == 1:
error_case = random.randint(0, 3)
if error_case == 0:
debug("Truncating JSON")
# Create bad JSON by truncating it
str_rep = output_str[:-len(output_str) // 2]
rc = str_rep
else:
if output_json is None:
output_json = json.loads(output_str)
if error_case == 1:
inject_key_error(output_json)
elif error_case == 2:
debug("Returning bad exit code")
inject_exit_error(output_json, 0)
else:
debug("Returning exit code 5")
inject_exit_error(output_json, 5)
rc = json.dumps(output_json) + "\n"
else:
rc = output_str
except Exception as e:
debug("Exception %s occurred: JSON = \n%s\n" % (str(e), output_str))
sys.exit(100)
return rc
def run_one(cmd):
debug("run_one(%s)" % str(cmd))
result = subprocess.run(cmd, capture_output=True, text=True)
if "fullreport" in cmd:
sys.stdout.write(inject_error(result.stdout))
else:
sys.stdout.write(result.stdout)
sys.stdout.flush()
sys.stderr.write(result.stderr)
sys.stderr.flush()
return result.returncode
class LvmShellHandler:
def __init__(self, cmd):
debug(os.environ)
self.d_stdout = deque()
self.d_stderr = deque()
self.d_report = deque()
tmp_dir = tempfile.mkdtemp(prefix="pipeinmiddle_")
self.tmp_file = "%s/middle_man_report" % tmp_dir
# Let's create a fifo for the report output
os.mkfifo(self.tmp_file, 0o600)
self.child_report_fd = os.open(self.tmp_file, os.O_NONBLOCK)
self.child_report_stream = os.fdopen(self.child_report_fd, 'rb', 0)
passed_report_fd = os.open(self.tmp_file, os.O_WRONLY)
debug("passed_report_fd = %d" % passed_report_fd)
# The report FD from who executed us.
self.daemon_report_fd = int(os.environ["LVM_REPORT_FD"])
self.daemon_report_stream = os.fdopen(self.daemon_report_fd, "wb", 0)
env = copy.deepcopy(os.environ)
env["LVM_REPORT_FD"] = "%s" % str(passed_report_fd)
env["LC_ALL"] = "C"
env["LVM_COMMAND_PROFILE"] = "lvmdbusd"
self.parent_stdin_fd, child_stdin_fd = pty.openpty()
self.parent_stdout_fd, child_stdout_fd = pty.openpty()
self.parent_stderr_fd, child_stderr_fd = pty.openpty()
self.parent_stdin = os.fdopen(self.parent_stdin_fd, "w")
self.parent_stdout = os.fdopen(self.parent_stdout_fd, "r")
self.parent_stderr = os.fdopen(self.parent_stderr_fd, "r")
debug("exec'ing %s" % cmd)
self.process = Popen(cmd,
stdin=child_stdin_fd,
stdout=child_stdout_fd,
stderr=child_stderr_fd,
close_fds=True,
env=env,
pass_fds=[passed_report_fd, ],
shell=False)
os.close(passed_report_fd)
os.close(child_stdin_fd)
os.close(child_stdout_fd)
os.close(child_stderr_fd)
make_non_block(self.parent_stdout_fd)
make_non_block(self.parent_stderr_fd)
make_non_block(sys.stdin)
self.report_text_in_progress = ""
self.last_request = ""
os.unlink(self.tmp_file)
os.rmdir(tmp_dir)
def _complete_response(self):
try:
_complete_json = json.loads(self.report_text_in_progress)
return _complete_json
except ValueError:
return None
def _write_all(self):
write_some(self.d_stderr, sys.stderr, remaining=True)
write_some(self.d_report, self.daemon_report_stream, remaining=True, binary=True)
write_some(self.d_stdout, sys.stdout, remaining=True)
def _handle_report(self):
# Read from child report stream, write to parent report stream
report_text = read_decoded(self.child_report_stream)
self.report_text_in_progress += report_text
report_json = self._complete_response()
# Always wait until we have a full response before we do anything with the output
if report_json is not None:
# Only add data to d_report after we have the entire JSON and have injected
# an error into it if we so wish, usually only for 'fullreport'
if "fullreport" in self.last_request:
self.d_report.extend(inject_error(self.report_text_in_progress, report_json))
else:
debug("Not the cmd we are looking for ...")
self.d_report.extend(self.report_text_in_progress)
self.report_text_in_progress = ""
def _handle_command(self):
global run
stdin_text = sys.stdin.readline()
self.last_request = stdin_text
debug("stdin: %s..." % stdin_text[:min(10, len(stdin_text) - 1)])
if "exit\n" in stdin_text:
debug("asking to exit ...")
run.value = 0
self.parent_stdin.writelines(stdin_text)
self.parent_stdin.flush()
@staticmethod
def _empty_stream_to_queue(stream, queue):
read_text = stream.readlines()
for line in read_text:
queue.extend(line)
def run(self):
global run
select_tmo = 0.2
while run.value == 1:
try:
rd_fd = [sys.stdin.fileno(), self.parent_stdout_fd, self.parent_stderr_fd, self.child_report_fd]
ready = select.select(rd_fd, [], [], select_tmo)
if len(ready[0]) == 0:
write_some(self.d_stderr, sys.stderr)
write_some(self.d_report, self.daemon_report_stream, binary=True)
for r in ready[0]:
if r == self.parent_stdout_fd:
LvmShellHandler._empty_stream_to_queue(self.parent_stdout, self.d_stdout)
elif r == self.parent_stderr_fd:
LvmShellHandler._empty_stream_to_queue(self.parent_stderr, self.d_stderr)
elif r == self.child_report_fd:
self._handle_report()
elif r == sys.stdin.fileno():
# Read from parent stdin write to child stdin, this is a command getting issued.
self._handle_command()
else:
debug("FD %d not handled!" % r)
sys.exit(10)
# We have handled all the FDs that were ready, write some output
if len(self.d_stdout) > 0:
self._write_all()
else:
write_some(self.d_stderr, sys.stderr)
write_some(self.d_report, self.daemon_report_stream, binary=True)
# Check to see if child process has terminated, None when running
if self.process.poll() is not None:
self._write_all()
debug("child process %s exited %d" % (cmd, self.process.returncode))
break
except IOError as ioe:
debug("run_cmd:" + str(ioe))
if self.process.poll() is not None:
debug("exiting %d " % self.process.returncode)
else:
debug("lvm process still running, be we are exiting ...")
return self.process.returncode
if __name__ == "__main__":
try:
args = sys.argv[1:]
exe = os.getenv("LVM_MAN_IN_MIDDLE", "/usr/sbin/lvm")
cmdline = [exe, ]
if args:
cmdline.extend(args)
ec = run_one(cmdline)
else:
SH = LvmShellHandler(cmdline)
ec = SH.run()
sys.exit(ec)
except Exception:
traceback.print_exc(file=d_out)
sys.exit(1)