Current File : //backups/router/usr/local/opnsense/scripts/interfaces/capture.py
#!/usr/local/bin/python3
"""
Copyright (c) 2022 Ad Schellevis <ad@opnsense.org>
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
"""
TEMP_DIR = '/tmp/captures/'
import argparse
import glob
import subprocess
import os
import sys
import ujson
import zipfile
from datetime import datetime
def capture_pids(jobid):
""" search for capture pids using output filename
:param jobid: job uuid number
:return: list of pids
"""
pids = []
args = ['/bin/pgrep', '-af', "%s%s" % (TEMP_DIR, jobid)]
for line in subprocess.run(args, capture_output=True, text=True).stdout.split():
if line.isdigit():
pids.append(line)
return pids
def load_settings(filename):
try:
return ujson.load(open(filename, 'r'))
except ValueError:
return {}
def pcap_reader(filename, eargs=None):
args = ['/usr/sbin/tcpdump', '-n', '-e', '-tt', '-r', filename]
if eargs:
args = args + eargs
sp = subprocess.Popen(args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
for line in sp.stdout:
if not line.startswith(b'reading'):
yield line.decode()
sp.communicate()
yield '\n'
if __name__ == '__main__':
result = dict()
parser = argparse.ArgumentParser()
parser.add_argument('--job', help='job id', default=None)
parser.add_argument('--detail', help='detail level', choices=['normal', 'medium','high'], default='normal')
parser.add_argument(
'action',
help='action to perfom',
choices=['list', 'start', 'stop', 'remove', 'view', 'archive']
)
cmd_args = parser.parse_args()
all_jobs = {}
if os.path.exists(TEMP_DIR):
for filename in glob.glob("%s*.json" % TEMP_DIR):
all_jobs[os.path.basename(filename).split('.')[0]] = filename
if cmd_args.action == 'list':
result['jobs'] = []
result['status'] = 'ok'
for jobid in all_jobs:
this_pids = capture_pids(jobid)
settings = load_settings(all_jobs[jobid])
settings['id'] = jobid
settings['status'] = "running" if len(this_pids) > 0 else "stopped"
result['jobs'].append(settings)
elif cmd_args.action == 'start' and cmd_args.job in all_jobs:
this_pids = capture_pids(cmd_args.job)
if len(this_pids) > 0:
result['status'] = 'failed'
result['status_msg'] = 'already active (pids: %s)' % ','.join(this_pids)
else:
result['status'] = 'ok'
result['started_processes'] = 0
settings = load_settings(all_jobs[cmd_args.job])
for intf in settings.get('interface', '').split(','):
result['started_processes'] += 1
args = [
'/usr/sbin/daemon',
'-f',
'/usr/sbin/tcpdump',
'-i', intf,
'-n',
'-U',
'-w', "%s%s_%s.pcap" % (TEMP_DIR, cmd_args.job, intf)
]
if settings.get('promiscuous', '0') == '1':
args.append('-p')
if settings.get('snaplen', '').isdigit():
args.append('-s')
args.append(settings.get('snaplen'))
if settings.get('count', '').isdigit() and int(settings.get('count')) > 0:
args.append('-c')
args.append(settings.get('count'))
filters = []
if settings.get('fam', 'any') != 'any':
filters.append(settings.get('fam'))
if settings.get('protocol', 'any') != 'any':
if settings.get('protocol_not', '0') == '1':
filters.append('proto not %s' % settings.get('protocol'))
else:
filters.append('proto %s' % settings.get('protocol'))
if settings.get('host', '') != '':
tokens = []
for token in settings.get('host').split():
if token.lower() in ['and', 'or', 'not']:
tokens.append(token)
elif token.find('/') > -1:
tokens.append('net %s' % token)
elif token.count(':') == 5 and sum([len(x) == 2 for x in token.split(':')]) == 6:
tokens.append('ether host %s' % token)
else:
tokens.append('host %s' % token)
filters.append('( %s )' % ' '.join(tokens))
if settings.get('port', '') != '':
if settings.get('port_not', '0') == '1':
filters.append('port not %s' % settings.get('port'))
else:
filters.append('port %s' % settings.get('port'))
if len(filters) > 0:
args.append(' and '.join(filters))
subprocess.run(args)
elif cmd_args.action == 'stop' and cmd_args.job in all_jobs:
result['status'] = 'ok'
result['stopped_processes'] = 0
for pid in capture_pids(cmd_args.job):
subprocess.run(['kill', pid])
result['stopped_processes'] += 1
elif cmd_args.action == 'remove' and cmd_args.job in all_jobs:
result['status'] = 'ok'
result['stopped_processes'] = 0
for pid in capture_pids(cmd_args.job):
subprocess.run(['kill', pid])
result['stopped_processes'] += 1
for filename in glob.glob("%s%s*" % (TEMP_DIR, cmd_args.job)):
os.remove(filename)
elif cmd_args.action == 'view' and cmd_args.job in all_jobs:
result['settings'] = load_settings(all_jobs[cmd_args.job])
result['status'] = 'ok'
result['interfaces'] = {}
for filename in glob.glob("%s%s*.pcap" % (TEMP_DIR, cmd_args.job)):
intf = filename.split('_', 1)[-1].rsplit('.', 1)[0]
result['interfaces'][intf] = {'rows': []}
args = []
if cmd_args.detail == 'normal':
args.append('-q')
elif cmd_args.detail == 'medium':
args.append('-v')
elif cmd_args.detail == 'high':
args.append('-vv')
this_record = []
for line in pcap_reader(filename, args):
if len(line) > 0 and not line[0] in [' ', '\t']:
if this_record and this_record[0].count(' ') > 3:
first_row = this_record[0].split()
if first_row[0].replace('.', '').isdigit():
this_record[0] = this_record[0][this_record[0].find(',')+1:].lstrip()
payload = {
'timestamp': datetime.fromtimestamp(float(first_row[0])).isoformat(),
'esrc': first_row[1] if first_row[1].count(':') == 5 else None,
'edst': first_row[3].rstrip(',') if first_row[3].count(':') == 5 > 0 else None,
'raw': ''.join(this_record)
}
if 'IPv4,' in first_row:
payload['fam'] = 'ip'
elif 'IPv6,' in first_row:
payload['fam'] = 'ip6'
result['interfaces'][intf]['rows'].append(payload)
if len(result['interfaces'][intf]['rows']) > 500:
# max frames reached
break
this_record = [line]
else:
this_record.append(line)
elif cmd_args.action == 'archive' and cmd_args.job in all_jobs:
result['filename'] = "%s%s.zip" % (TEMP_DIR, cmd_args.job)
result['status'] = 'ok'
zfh = zipfile.ZipFile(result['filename'], mode='w')
for filename in glob.glob("%s%s*" % (TEMP_DIR, cmd_args.job)):
if not filename.endswith('.zip'):
zfh.write(filename, os.path.basename(filename))
zfh.close()
print (ujson.dumps(result))
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