chrony/SOURCES/ntp2chrony.py

681 lines
24 KiB
Python

#!/usr/bin/python3
#
# Convert ntp configuration to chrony
#
# Copyright (C) 2018-2019 Miroslav Lichvar <mlichvar@redhat.com>
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
import argparse
import ipaddress
import logging
import os
import re
import subprocess
import sys
# python2 compatibility hacks
if sys.version_info[0] < 3:
from io import open
reload(sys)
sys.setdefaultencoding("utf-8")
class NtpConfiguration(object):
def __init__(self, root_dir, ntp_conf, step_tickers):
self.root_dir = root_dir if root_dir != "/" else ""
self.ntp_conf_path = ntp_conf
self.step_tickers_path = step_tickers
# Read and write files using an 8-bit transparent encoding
self.file_encoding = "latin-1"
self.enabled_services = set()
self.step_tickers = []
self.time_sources = []
self.fudges = {}
self.restrictions = {
# Built-in defaults
ipaddress.ip_network(u"0.0.0.0/0"): set(),
ipaddress.ip_network(u"::/0"): set(),
}
self.keyfile = ""
self.keys = []
self.trusted_keys = []
self.driftfile = ""
self.statistics = []
self.leapfile = ""
self.tos_options = {}
self.ignored_directives = set()
self.ignored_lines = []
# self.detect_enabled_services()
self.parse_step_tickers()
self.parse_ntp_conf()
def detect_enabled_services(self):
for service in ["ntpdate", "ntpd", "ntp-wait"]:
service_path = os.path.join(self.root_dir,
"etc/systemd/system/multi-user.target.wants/{}.service".format(service))
if os.path.islink(service_path):
self.enabled_services.add(service)
logging.info("Enabled services found in /etc/systemd/system: %s",
" ".join(self.enabled_services))
def parse_step_tickers(self):
if not self.step_tickers_path:
return
path = os.path.join(self.root_dir, self.step_tickers_path)
if not os.path.isfile(path):
logging.info("Missing %s", path)
return
with open(path, encoding=self.file_encoding) as f:
for line in f:
line = line[:line.find('#')]
words = line.split()
if not words:
continue
self.step_tickers.extend(words)
def parse_ntp_conf(self, path=None):
if path is None:
path = os.path.join(self.root_dir, self.ntp_conf_path)
with open(path, encoding=self.file_encoding) as f:
logging.info("Reading %s", path)
for line in f:
line = line[:line.find('#')]
words = line.split()
if not words:
continue
if not self.parse_directive(words):
self.ignored_lines.append(line)
def parse_directive(self, words):
name = words.pop(0)
if name.startswith("logconfig"):
name = "logconfig"
if words:
if name in ["server", "peer", "pool"]:
return self.parse_source(name, words)
elif name == "fudge":
return self.parse_fudge(words)
elif name == "restrict":
return self.parse_restrict(words)
elif name == "tos":
return self.parse_tos(words)
elif name == "includefile":
return self.parse_includefile(words)
elif name == "keys":
return self.parse_keys(words)
elif name == "trustedkey":
return self.parse_trustedkey(words)
elif name == "driftfile":
self.driftfile = words[0]
elif name == "statistics":
self.statistics = words
elif name == "leapfile":
self.leapfile = words[0]
else:
self.ignored_directives.add(name)
return False
else:
self.ignored_directives.add(name)
return False
return True
def parse_source(self, source_type, words):
ipv4_only = False
ipv6_only = False
source = {
"type": source_type,
"options": []
}
if words[0] == "-4":
ipv4_only = True
words.pop(0)
elif words[0] == "-6":
ipv6_only = True
words.pop(0)
if not words:
return False
source["address"] = words.pop(0)
# Check if -4/-6 corresponds to the address and ignore hostnames
if ipv4_only or ipv6_only:
try:
version = ipaddress.ip_address(source["address"]).version
if (ipv4_only and version != 4) or (ipv6_only and version != 6):
return False
except ValueError:
return False
if source["address"].startswith("127.127."):
if not source["address"].startswith("127.127.1."):
# Ignore non-LOCAL refclocks
return False
while words:
if len(words) >= 2 and words[0] in ["minpoll", "maxpoll", "version", "key"]:
source["options"].append((words[0], words[1]))
words = words[2:]
elif words[0] in ["burst", "iburst", "noselect", "prefer", "true", "xleave"]:
source["options"].append((words[0],))
words.pop(0)
else:
return False
self.time_sources.append(source)
return True
def parse_fudge(self, words):
address = words.pop(0)
options = {}
while words:
if len(words) >= 2 and words[0] in ["stratum"]:
if not words[1].isdigit():
return False
options[words[0]] = int(words[1])
words = words[2:]
elif len(words) >= 2:
words = words[2:]
else:
return False
self.fudges[address] = options
return True
def parse_restrict(self, words):
ipv4_only = False
ipv6_only = False
flags = set()
mask = ""
if words[0] == "-4":
ipv4_only = True
words.pop(0)
elif words[0] == "-6":
ipv6_only = True
words.pop(0)
if not words:
return False
address = words.pop(0)
while words:
if len(words) >= 2 and words[0] == "mask":
mask = words[1]
words = words[2:]
else:
if words[0] not in ["kod", "nomodify", "notrap", "nopeer", "noquery",
"limited", "ignore", "noserve"]:
return False
flags.add(words[0])
words.pop(0)
# Convert to IP network(s), ignoring restrictions with hostnames
networks = []
if address == "default" and not mask:
if not ipv6_only:
networks.append(ipaddress.ip_network(u"0.0.0.0/0"))
if not ipv4_only:
networks.append(ipaddress.ip_network(u"::/0"))
else:
try:
if mask:
# Count bits in the mask (ipaddress does not support
# expanded IPv6 netmasks)
mask_ip = ipaddress.ip_address(mask)
mask_str = "{0:0{1}b}".format(int(mask_ip), mask_ip.max_prefixlen)
networks.append(ipaddress.ip_network(
u"{}/{}".format(address, len(mask_str.rstrip('0')))))
else:
networks.append(ipaddress.ip_network(address))
except ValueError:
return False
if (ipv4_only and networks[-1].version != 4) or \
(ipv6_only and networks[-1].version != 6):
return False
for network in networks:
self.restrictions[network] = flags
return True
def parse_tos(self, words):
options = {}
while words:
if len(words) >= 2 and words[0] in ["minsane", "orphan"]:
if not words[1].isdigit():
return False
options[words[0]] = int(words[1])
words = words[2:]
elif len(words) >= 2 and words[0] in ["maxdist"]:
# Check if it is a float value
if not words[1].replace('.', '', 1).isdigit():
return False
options[words[0]] = float(words[1])
words = words[2:]
else:
return False
self.tos_options.update(options)
return True
def parse_includefile(self, words):
path = os.path.join(self.root_dir, words[0])
if not os.path.isfile(path):
return False
self.parse_ntp_conf(path)
return True
def parse_keys(self, words):
keyfile = words[0]
path = os.path.join(self.root_dir, keyfile)
if not os.path.isfile(path):
logging.info("Missing %s", path)
return False
with open(path, encoding=self.file_encoding) as f:
logging.info("Reading %s", path)
keys = []
for line in f:
words = line.split()
if len(words) < 3 or not words[0].isdigit():
continue
keys.append((int(words[0]), words[1], words[2]))
self.keyfile = keyfile
self.keys = keys
return True
def parse_trustedkey(self, words):
key_ranges = []
for word in words:
if word.isdigit():
key_ranges.append((int(word), int(word)))
elif re.match("^[0-9]+-[0-9]+$", word):
first, last = word.split("-")
key_ranges.append((int(first), int(last)))
else:
return False
self.trusted_keys = key_ranges
return True
def write_chrony_configuration(self, chrony_conf_path, chrony_keys_path,
dry_run=False, backup=False):
chrony_conf = self.get_chrony_conf(chrony_keys_path)
logging.debug("Generated %s:\n%s", chrony_conf_path, chrony_conf)
if not dry_run:
self.write_file(chrony_conf_path, 0o644, chrony_conf, backup)
chrony_keys = self.get_chrony_keys()
if chrony_keys:
logging.debug("Generated %s:\n%s", chrony_keys_path, chrony_keys)
if not dry_run:
self.write_file(chrony_keys_path, 0o640, chrony_keys, backup)
def get_processed_time_sources(self):
# Convert {0,1,2,3}.*pool.ntp.org servers to 2.*pool.ntp.org pools
# Make shallow copies of all sources (only type will be modified)
time_sources = [s.copy() for s in self.time_sources]
pools = {}
for source in time_sources:
if source["type"] != "server":
continue
m = re.match("^([0123])(\\.\\w+)?\\.pool\\.ntp\\.org$", source["address"])
if m is None:
continue
number = m.group(1)
zone = m.group(2)
if zone not in pools:
pools[zone] = []
pools[zone].append((int(number), source))
remove_servers = set()
for zone, pool in pools.items():
# sort and skip all pools not in [0, 3] range
pool.sort()
if [number for number, source in pool] != [0, 1, 2, 3]:
# only exact group of 4 servers can be converted, nothing to do here
continue
# verify that parameters are the same for all servers in the pool
if not all([p[1]["options"] == pool[0][1]["options"] for p in pool]):
break
remove_servers.update([pool[i][1]["address"] for i in [0, 1, 3]])
pool[2][1]["type"] = "pool"
processed_sources = []
for source in time_sources:
if source["type"] == "server" and source["address"] in remove_servers:
continue
processed_sources.append(source)
return processed_sources
def get_chrony_conf_sources(self):
conf = ""
if self.step_tickers:
conf += "# Specify NTP servers used for initial correction.\n"
conf += "initstepslew 0.1 {}\n".format(" ".join(self.step_tickers))
conf += "\n"
conf += "# Specify time sources.\n"
for source in self.get_processed_time_sources():
address = source["address"]
if address.startswith("127.127."):
if address.startswith("127.127.1."):
continue
# No other refclocks are expected from the parser
assert False
else:
conf += "{} {}".format(source["type"], address)
for option in source["options"]:
if option[0] in ["minpoll", "maxpoll", "version", "key",
"iburst", "noselect", "prefer", "xleave"]:
conf += " {}".format(" ".join(option))
elif option[0] == "burst":
conf += " presend 6"
elif option[0] == "true":
conf += " trust"
else:
# No other options are expected from the parser
assert False
conf += "\n"
conf += "\n"
return conf
def get_chrony_conf_allows(self):
allowed_networks = filter(lambda n: "ignore" not in self.restrictions[n] and
"noserve" not in self.restrictions[n],
self.restrictions.keys())
conf = ""
for network in sorted(allowed_networks, key=lambda n: (n.version, n)):
if network.num_addresses > 1:
conf += "allow {}\n".format(network)
else:
conf += "allow {}\n".format(network.network_address)
if conf:
conf = "# Allow NTP client access.\n" + conf
conf += "\n"
return conf
def get_chrony_conf_cmdallows(self):
allowed_networks = filter(lambda n: "ignore" not in self.restrictions[n] and
"noquery" not in self.restrictions[n] and
n != ipaddress.ip_network(u"127.0.0.1/32") and
n != ipaddress.ip_network(u"::1/128"),
self.restrictions.keys())
ip_versions = set()
conf = ""
for network in sorted(allowed_networks, key=lambda n: (n.version, n)):
ip_versions.add(network.version)
if network.num_addresses > 1:
conf += "cmdallow {}\n".format(network)
else:
conf += "cmdallow {}\n".format(network.network_address)
if conf:
conf = "# Allow remote monitoring.\n" + conf
if 4 in ip_versions:
conf += "bindcmdaddress 0.0.0.0\n"
if 6 in ip_versions:
conf += "bindcmdaddress ::\n"
conf += "\n"
return conf
def get_chrony_conf(self, chrony_keys_path):
local_stratum = 0
maxdistance = 0.0
minsources = 1
orphan_stratum = 0
logs = []
for source in self.time_sources:
address = source["address"]
if address.startswith("127.127.1."):
if address in self.fudges and "stratum" in self.fudges[address]:
local_stratum = self.fudges[address]["stratum"]
else:
local_stratum = 5
if "maxdist" in self.tos_options:
maxdistance = self.tos_options["maxdist"]
if "minsane" in self.tos_options:
minsources = self.tos_options["minsane"]
if "orphan" in self.tos_options:
orphan_stratum = self.tos_options["orphan"]
if "clockstats" in self.statistics:
logs.append("refclocks")
if "loopstats" in self.statistics:
logs.append("tracking")
if "peerstats" in self.statistics:
logs.append("statistics")
if "rawstats" in self.statistics:
logs.append("measurements")
conf = "# This file was converted from {}{}.\n".format(
self.ntp_conf_path,
" and " + self.step_tickers_path if self.step_tickers_path else "")
conf += "\n"
if self.ignored_lines:
conf += "# The following directives were ignored in the conversion:\n"
for line in self.ignored_lines:
# Remove sensitive information
line = re.sub(r"\s+pw\s+\S+", " pw XXX", line.rstrip())
conf += "# " + line + "\n"
conf += "\n"
conf += self.get_chrony_conf_sources()
conf += "# Record the rate at which the system clock gains/losses time.\n"
if not self.driftfile:
conf += "#"
conf += "driftfile /var/lib/chrony/drift\n"
conf += "\n"
conf += "# Allow the system clock to be stepped in the first three updates\n"
conf += "# if its offset is larger than 1 second.\n"
conf += "makestep 1.0 3\n"
conf += "\n"
conf += "# Enable kernel synchronization of the real-time clock (RTC).\n"
conf += "rtcsync\n"
conf += "\n"
conf += "# Enable hardware timestamping on all interfaces that support it.\n"
conf += "#hwtimestamp *\n"
conf += "\n"
if maxdistance > 0.0:
conf += "# Specify the maximum distance of sources to be selectable.\n"
conf += "maxdistance {}\n".format(maxdistance)
conf += "\n"
conf += "# Increase the minimum number of selectable sources required to adjust\n"
conf += "# the system clock.\n"
if minsources > 1:
conf += "minsources {}\n".format(minsources)
else:
conf += "#minsources 2\n"
conf += "\n"
conf += self.get_chrony_conf_allows()
conf += self.get_chrony_conf_cmdallows()
conf += "# Serve time even if not synchronized to a time source.\n"
if orphan_stratum > 0 and orphan_stratum < 16:
conf += "local stratum {} orphan\n".format(orphan_stratum)
elif local_stratum > 0 and local_stratum < 16:
conf += "local stratum {}\n".format(local_stratum)
else:
conf += "#local stratum 10\n"
conf += "\n"
conf += "# Specify file containing keys for NTP authentication.\n"
conf += "keyfile {}\n".format(chrony_keys_path)
conf += "\n"
conf += "# Get TAI-UTC offset and leap seconds from the system tz database.\n"
conf += "leapsectz right/UTC\n"
conf += "\n"
conf += "# Specify directory for log files.\n"
conf += "logdir /var/log/chrony\n"
conf += "\n"
conf += "# Select which information is logged.\n"
if logs:
conf += "log {}\n".format(" ".join(logs))
else:
conf += "#log measurements statistics tracking\n"
return conf
def get_chrony_keys(self):
if not self.keyfile:
return ""
keys = "# This file was converted from {}.\n".format(self.keyfile)
keys += "\n"
for key in self.keys:
key_id = key[0]
key_type = key[1]
password = key[2]
if key_type in ["m", "M"]:
key_type = "MD5"
elif key_type == "AES128CMAC":
key_type = "AES128"
elif key_type not in ["MD5", "SHA1", "SHA256", "SHA384", "SHA512"]:
continue
prefix = "ASCII" if len(password) <= 20 else "HEX"
for first, last in self.trusted_keys:
if first <= key_id <= last:
trusted = True
break
else:
trusted = False
# Disable keys that were not marked as trusted
if not trusted:
keys += "#"
keys += "{} {} {}:{}\n".format(key_id, key_type, prefix, password)
return keys
def write_file(self, path, mode, content, backup):
path = self.root_dir + path
if backup and os.path.isfile(path):
os.rename(path, path + ".old")
with open(os.open(path, os.O_CREAT | os.O_WRONLY | os.O_EXCL, mode), "w",
encoding=self.file_encoding) as f:
logging.info("Writing %s", path)
f.write(u"" + content)
# Fix SELinux context if restorecon is installed
try:
subprocess.call(["restorecon", path])
except OSError:
pass
def main():
parser = argparse.ArgumentParser(description="Convert ntp configuration to chrony.")
parser.add_argument("-r", "--root", dest="roots", default=["/"], nargs="+",
metavar="DIR", help="specify root directory (default /)")
parser.add_argument("--ntp-conf", action="store", default="/etc/ntp.conf",
metavar="FILE", help="specify ntp config (default /etc/ntp.conf)")
parser.add_argument("--step-tickers", action="store", default="",
metavar="FILE", help="specify ntpdate step-tickers config (no default)")
parser.add_argument("--chrony-conf", action="store", default="/etc/chrony.conf",
metavar="FILE", help="specify chrony config (default /etc/chrony.conf)")
parser.add_argument("--chrony-keys", action="store", default="/etc/chrony.keys",
metavar="FILE", help="specify chrony keyfile (default /etc/chrony.keys)")
parser.add_argument("-b", "--backup", action="store_true", help="backup existing configs before writing")
parser.add_argument("-L", "--ignored-lines", action="store_true", help="print ignored lines")
parser.add_argument("-D", "--ignored-directives", action="store_true",
help="print names of ignored directives")
parser.add_argument("-n", "--dry-run", action="store_true", help="don't make any changes")
parser.add_argument("-v", "--verbose", action="count", default=0, help="increase verbosity")
args = parser.parse_args()
logging.basicConfig(format="%(message)s",
level=[logging.ERROR, logging.INFO, logging.DEBUG][min(args.verbose, 2)])
for root in args.roots:
conf = NtpConfiguration(root, args.ntp_conf, args.step_tickers)
if args.ignored_lines:
for line in conf.ignored_lines:
print(line)
if args.ignored_directives:
for directive in conf.ignored_directives:
print(directive)
conf.write_chrony_configuration(args.chrony_conf, args.chrony_keys, args.dry_run, args.backup)
if __name__ == "__main__":
main()