ntpclients/ntptrace.py

   1 #! @PYSHEBANG@
   2 # -*- coding: utf-8 -*-
   3 """
   4 ntptrace - trace peers of an NTP server
   5
   6 Usage: ntptrace [-n | --numeric] [-m number | --max-hosts=number]
   7                 [-r hostname | --host=hostname] [--help | --more-help]
   8                 [-V | --version]
   9                 hostname
  10
  11 See the manual page for details.
  12 """
  13
  14 # Copyright the NTPsec project contributors
  15 #
  16 # SPDX-License-Identifier: BSD-2-Clause
  17
  18 from __future__ import print_function
  19
  20 import getopt
  21 import re
  22 import subprocess
  23 import sys
  24
  25 try:
  26     import ntp.util
  27 except ImportError as e:
  28     sys.stderr.write(
  29         "ntptrace: can't find Python NTP library.\n")
  30     sys.stderr.write("%s\n" % e)
  31     sys.exit(1)
  32
  33
  34 def get_info(host):
  35     info = ntp_read_vars(0, [], host)
  36     if info is None or 'stratum' not in info:
  37         return
  38
  39     info['offset'] = round(float(info['offset']) / 1000, 6)
  40     info['syncdistance'] = \
  41         (float(info['rootdisp']) + (float(info['rootdelay']) / 2)) / 1000
  42
  43     return info
  44
  45
  46 def get_next_host(peer, host):
  47     info = ntp_read_vars(peer, ["srcadr"], host)
  48     if info is None:
  49         return
  50     return info['srcadr']
  51
  52
  53 def ntp_read_vars(peer, vars, host):
  54     obsolete = {'phase': 'offset',
  55                 'rootdispersion': 'rootdisp'}
  56
  57     if not vars:
  58         do_all = True
  59     else:
  60         do_all = False
  61     outvars = {}.fromkeys(vars)
  62
  63     if do_all:
  64         outvars['status_line'] = {}
  65
  66     cmd = ["ntpq", "-n", "-c", "rv %s %s" % (peer, ",".join(vars))]
  67     if host is not None:
  68         cmd.append(host)
  69
  70     try:
  71         # sadly subprocess.check_output() is not in Python 2.6
  72         proc = subprocess.Popen(
  73             cmd,
  74             stdout=subprocess.PIPE,
  75             stderr=subprocess.STDOUT)
  76         out = proc.communicate()[0]
  77         output = out.decode('utf-8').splitlines()
  78     except subprocess.CalledProcessError as e:
  79         print("Could not start ntpq: %s" % e.output, file=sys.stderr)
  80         raise SystemExit(1)
  81     except OSError as e:
  82         print("Could not start ntpq: %s" % e.strerror, file=sys.stderr)
  83         raise SystemExit(1)
  84
  85     for line in output:
  86         if re.search(r'Connection refused', line):
  87             return
  88
  89         match = re.search(r'^asso?c?id=0 status=(\S{4}) (\S+), (\S+),', line,
  90                           flags=re.IGNORECASE)
  91         if match:
  92             outvars['status_line']['status'] = match.group(1)
  93             outvars['status_line']['leap'] = match.group(2)
  94             outvars['status_line']['sync'] = match.group(3)
  95
  96         iterator = re.finditer(r'(\w+)=([^,]+),?\s?', line)
  97         for match in iterator:
  98             key = match.group(1)
  99             val = match.group(2)
 100             val = re.sub(r'^"([^"]+)"$', r'\1', val)
 101             if key in obsolete:
 102                 key = obsolete[key]
 103             if do_all or key in outvars:
 104                 outvars[key] = val
 105
 106     return outvars
 107
 108
 109 usage = r"""ntptrace - trace peers of an NTP server
 110 USAGE: ntptrace [-<flag> [<val>] | --<name>[{=| }<val>]]... [host]
 111
 112     -n, --numeric                Print IP addresses instead of hostnames
 113     -m, --max-hosts=num          Maximum number of peers to trace
 114     -r, --host=str               Single remote host
 115     -?, --help                   Display usage information and exit
 116         --more-help              Pass the extended usage text through a pager
 117     -V, --version                Output version information and exit
 118
 119 Options are specified by doubled hyphens and their name or by a single
 120 hyphen and the flag character.""" + "\n"
 121
 122 bin_ver = "ntpsec-@NTPSEC_VERSION_EXTENDED@"
 123 ntp.util.stdversioncheck(bin_ver)
 124
 125 try:
 126     (options, arguments) = getopt.getopt(
 127         sys.argv[1:], "m:nr:?V",
 128         ["help", "host=", "max-hosts=", "more-help", "numeric", "version"])
 129 except getopt.GetoptError as err:
 130     sys.stderr.write(str(err) + "\n")
 131     raise SystemExit(1)
 132
 133 numeric = False
 134 maxhosts = 99
 135 host = '127.0.0.1'
 136
 137 for (switch, val) in options:
 138     if switch == "-m" or switch == "--max-hosts":
 139         errmsg = "Error: -m parameter '%s' not a number\n"
 140         maxhosts = ntp.util.safeargcast(val, int, errmsg, usage)
 141     elif switch == "-n" or switch == "--numeric":
 142         numeric = True
 143     elif switch == "-r" or switch == "--host":
 144         host = val
 145     elif switch == "-?" or switch == "--help" or switch == "--more-help":
 146         print(usage, file=sys.stderr)
 147         raise SystemExit(0)
 148     elif switch == "-V" or switch == "--version":
 149         print("ntptrace %s" % ntp.util.stdversion())
 150         raise SystemExit(0)
 151
 152 if arguments:
 153     host = arguments[0]
 154
 155 hostcount = 0
 156
 157 while True:
 158     hostcount += 1
 159
 160     info = get_info(host)
 161
 162     if info is None:
 163         break
 164
 165     if not numeric:
 166         host = ntp.util.canonicalize_dns(host)
 167
 168     print("%s: stratum %d, offset %f, synch distance %f" %
 169           (host, int(info['stratum']), info['offset'], info['syncdistance']),
 170           end='')
 171     if int(info['stratum']) == 1:
 172         print(", refid '%s'" % info['refid'], end='')
 173     print()
 174
 175     if (int(info['stratum']) == 0 or int(info['stratum']) == 1 or
 176             int(info['stratum']) == 16):
 177         break
 178
 179     if re.search(r'^127\.127\.\d{1,3}\.\d{1,3}$', info['refid']):
 180         break
 181
 182     if hostcount == maxhosts:
 183         break
 184
 185     next_host = get_next_host(info['peer'], host)
 186
 187     if next_host is None:
 188         break
 189     if re.search(r'^127\.127\.\d{1,3}\.\d{1,3}$', next_host):
 190         break
 191
 192     host = next_host