diff options
| -rw-r--r-- | debian/control | 1 | ||||
| -rw-r--r-- | python/vyos/hostsd_client.py | 56 | ||||
| -rwxr-xr-x | src/services/vyos-hostsd | 254 | ||||
| -rw-r--r-- | src/systemd/vyos-hostsd.service | 22 | ||||
| -rwxr-xr-x | src/utils/vyos-hostsd-client | 82 |
5 files changed, 415 insertions, 0 deletions
diff --git a/debian/control b/debian/control index e99319124..8ad0ff1df 100644 --- a/debian/control +++ b/debian/control @@ -27,6 +27,7 @@ Depends: python3, python3-isc-dhcp-leases, python3-hurry.filesize, python3-vici (>= 5.7.2), + python3-zmq, ipaddrcheck, tcpdump, tshark, diff --git a/python/vyos/hostsd_client.py b/python/vyos/hostsd_client.py new file mode 100644 index 000000000..e02aefe6f --- /dev/null +++ b/python/vyos/hostsd_client.py @@ -0,0 +1,56 @@ +import json + +import zmq + + +SOCKET_PATH = "ipc:///run/vyos-hostsd.sock" + + +class VyOSHostsdError(Exception): + pass + + +class Client(object): + def __init__(self): + context = zmq.Context() + self.__socket = context.socket(zmq.REQ) + self.__socket.RCVTIMEO = 10000 #ms + self.__socket.setsockopt(zmq.LINGER, 0) + self.__socket.connect(SOCKET_PATH) + + def _communicate(self, msg): + request = json.dumps(msg).encode() + self.__socket.send(request) + + reply_msg = self.__socket.recv().decode() + reply = json.loads(reply_msg) + if 'error' in reply: + raise VyOSHostsdError(reply['error']) + + def set_host_name(self, host_name, domain_name, search_domains): + msg = { + 'type': 'host_name', + 'op': 'set', + 'data': { + 'host_name': host_name, + 'domain_name': domain_name, + 'search_domains': search_domains + } + } + self._communicate(msg) + + def add_hosts(self, tag, hosts): + msg = {'type': 'hosts', 'op': 'add', 'tag': tag, 'data': hosts} + self._communicate(msg) + + def delete_hosts(self, tag): + msg = {'type': 'hosts', 'op': 'delete', 'tag': tag} + self._communicate(msg) + + def add_name_servers(self, tag, servers): + msg = {'type': 'name_servers', 'op': 'add', 'tag': tag, 'data': servers} + self._communicate(msg) + + def delete_name_servers(self, tag): + msg = {'type': 'name_servers', 'op': 'delete', 'tag': tag} + self._communicate(msg) diff --git a/src/services/vyos-hostsd b/src/services/vyos-hostsd new file mode 100755 index 000000000..972c2e3dc --- /dev/null +++ b/src/services/vyos-hostsd @@ -0,0 +1,254 @@ +#!/usr/bin/env python3 +# +# Copyright (C) 2019 VyOS maintainers and contributors +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License version 2 or later as +# published by the Free Software Foundation. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. +# +# + +import os +import sys +import time +import json +import traceback + +import zmq + +import jinja2 + +debug = True + +DATA_DIR = "/var/lib/vyos/" +STATE_FILE = os.path.join(DATA_DIR, "hostsd.state") + +SOCKET_PATH = "ipc:///run/vyos-hostsd.sock" + +RESOLV_CONF_FILE = '/etc/resolv.conf' +HOSTS_FILE = '/etc/hosts' + +hosts_tmpl_source = """ +### Autogenerated by VyOS ### +127.0.0.1 localhost +127.0.1.1 {{ host_name }}{% if domain_name %}.{{ domain_name }}{% endif %} + +# The following lines are desirable for IPv6 capable hosts +::1 localhost ip6-localhost ip6-loopback +fe00::0 ip6-localnet +ff00::0 ip6-mcastprefix +ff02::1 ip6-allnodes +ff02::2 ip6-allrouters + + +{%- if hosts %} +{% for h in hosts -%} +{{hosts[h]['address']}}\t{{h}}\t{% for a in hosts[h]['aliases'] %} {{a}} {% endfor %} +{% endfor %} +{%- endif %} +""" + +hosts_tmpl = jinja2.Template(hosts_tmpl_source) + +resolv_tmpl_source = """ +### Autogenerated by VyOS ### +{% for ns in name_servers -%} +nameserver {{ns}} +{% endfor -%} + +{%- if domain_name %} +domain {{ domain_name }} +{%- endif %} + +{%- if search_domains %} +search {{ search_domains | join(" ") }} +{%- endif %} + +""" + +resolv_tmpl = jinja2.Template(resolv_tmpl_source) + +# The state data includes a list of name servers +# and a list of hosts entries. +# +# Name servers have the following structure: +# {"server": {"tag": <str>}} +# +# Hosts entries are similar: +# {"host": {"tag": <str>, "address": <str>}} +# +# The tag is either "static" or "dhcp-<intf>" +# It's used to distinguish entries created +# by different scripts so that they can be removed +# and re-created without having to track what needs +# to be changed +STATE = { + "name_servers": {}, + "hosts": {}, + "host_name": "vyos", + "domain_name": "", + "search_domains": []} + + +def make_resolv_conf(data): + resolv_conf = resolv_tmpl.render(data) + print("Writing /etc/resolv.conf") + with open(RESOLV_CONF_FILE, 'w') as f: + f.write(resolv_conf) + +def make_hosts_file(state): + print("Writing /etc/hosts") + hosts = hosts_tmpl.render(state) + with open(HOSTS_FILE, 'w') as f: + f.write(hosts) + +def add_hosts(data, entries, tag): + hosts = data['hosts'] + + if not entries: + return + + for e in entries: + host = e['host'] + hosts[host] = {} + hosts[host]['tag'] = tag + hosts[host]['address'] = e['address'] + hosts[host]['aliases'] = e['aliases'] + +def delete_hosts(data, tag): + hosts = data['hosts'] + keys_for_deletion = [] + + # You can't delete items from a dict while iterating over it, + # so we build a list of doomed items first + for h in hosts: + if hosts[h]['tag'] == tag: + keys_for_deletion.append(h) + + for k in keys_for_deletion: + del hosts[k] + +def add_name_servers(data, entries, tag): + name_servers = data['name_servers'] + + if not entries: + return + + for e in entries: + name_servers[e] = {} + name_servers[e]['tag'] = tag + +def delete_name_servers(data, tag): + name_servers = data['name_servers'] + keys_for_deletion = [] + + for ns in name_servers: + if name_servers[ns]['tag'] == tag: + keys_for_deletion.append(ns) + + for k in keys_for_deletion: + del name_servers[k] + +def set_host_name(state, data): + if data['host_name']: + state['host_name'] = data['host_name'] + if data['domain_name']: + state['domain_name'] = data['domain_name'] + if data['search_domains']: + state['search_domains'] = data['search_domains'] + +def get_option(msg, key): + if key in msg: + return msg[key] + else: + raise ValueError("Missing required option \"{0}\"".format(key)) + +def handle_message(msg_json): + msg = json.loads(msg_json) + + op = get_option(msg, 'op') + _type = get_option(msg, 'type') + + if op == 'delete': + tag = get_option(msg, 'tag') + + if _type == 'name_servers': + delete_name_servers(STATE, tag) + elif _type == 'hosts': + delete_hosts(STATE, tag) + else: + raise ValueError("Unknown message type {0}".format(_type)) + elif op == 'add': + tag = get_option(msg, 'tag') + entries = get_option(msg, 'data') + if _type == 'name_servers': + add_name_servers(STATE, entries, tag) + elif _type == 'hosts': + add_hosts(STATE, entries, tag) + else: + raise ValueError("Unknown message type {0}".format(_type)) + elif op == 'set': + # Host name/domain name/search domain are set without a tag, + # there can be only one anyway + data = get_option(msg, 'data') + if _type == 'host_name': + set_host_name(STATE, data) + else: + raise ValueError("Unknown message type {0}".format(_type)) + else: + raise ValueError("Unknown operation {0}".format(op)) + + make_resolv_conf(STATE) + make_hosts_file(STATE) + + print("Saving state to {0}".format(STATE_FILE)) + with open(STATE_FILE, 'w') as f: + json.dump(STATE, f) + + +if __name__ == '__main__': + # Create a directory for state checkpoints + os.makedirs(DATA_DIR, exist_ok=True) + if os.path.exists(STATE_FILE): + with open(STATE_FILE, 'r') as f: + try: + data = json.load(f) + STATE = data + except: + print(traceback.format_exc()) + print("Failed to load the state file, using default") + + context = zmq.Context() + socket = context.socket(zmq.REP) + socket.bind(SOCKET_PATH) + + while True: + # Wait for next request from client + message = socket.recv().decode() + print("Received a configuration change request") + if debug: + print("Request data: {0}".format(message)) + + resp = {} + + try: + handle_message(message) + except ValueError as e: + resp['error'] = str(e) + except: + print(traceback.format_exc()) + resp['error'] = "Internal error" + + if debug: + print("Sent response: {0}".format(resp)) + + # Send reply back to client + socket.send(json.dumps(resp).encode()) diff --git a/src/systemd/vyos-hostsd.service b/src/systemd/vyos-hostsd.service new file mode 100644 index 000000000..fe6c163d7 --- /dev/null +++ b/src/systemd/vyos-hostsd.service @@ -0,0 +1,22 @@ +[Unit] +Description=VyOS DNS configuration keeper +After=auditd.service systemd-user-sessions.service time-sync.target + +[Service] +ExecStart=/usr/bin/python3 -u /usr/libexec/vyos/services/vyos-hostsd +Type=idle +KillMode=process + +SyslogIdentifier=vyos-hostsd +SyslogFacility=daemon + +Restart=on-failure + +# Does't work but leave it here +User=root +Group=vyattacfg + +[Install] +# Installing in a earlier target leaves ExecStartPre waiting +WantedBy=getty.target + diff --git a/src/utils/vyos-hostsd-client b/src/utils/vyos-hostsd-client new file mode 100755 index 000000000..d3105c9cf --- /dev/null +++ b/src/utils/vyos-hostsd-client @@ -0,0 +1,82 @@ +#!/usr/bin/env python3 +# +# Copyright (C) 2019 VyOS maintainers and contributors +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License version 2 or later as +# published by the Free Software Foundation. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. +# +# + +import sys +import argparse + +import vyos.hostsd_client + +parser = argparse.ArgumentParser() +group = parser.add_mutually_exclusive_group() +group.add_argument('--add-hosts', action="store_true") +group.add_argument('--delete-hosts', action="store_true") +group.add_argument('--add-name-servers', action="store_true") +group.add_argument('--delete-name-servers', action="store_true") +group.add_argument('--set-host-name', action="store_true") + +parser.add_argument('--host', type=str, action="append") +parser.add_argument('--name-server', type=str, action="append") +parser.add_argument('--host-name', type=str) +parser.add_argument('--domain-name', type=str) +parser.add_argument('--search-domain', type=str, action="append") + +parser.add_argument('--tag', type=str) + +args = parser.parse_args() + +try: + client = vyos.hostsd_client.Client() + + if args.add_hosts: + if not args.tag: + raise ValueError("Tag is required for this operation") + data = [] + for h in args.host: + entry = {} + params = h.split(",") + if len(params) < 2: + raise ValueError("Malformed host entry") + entry['host'] = params[0] + entry['address'] = params[1] + entry['aliases'] = params[2:] + data.append(entry) + client.add_hosts(args.tag, data) + elif args.delete_hosts: + if not args.tag: + raise ValueError("Tag is required for this operation") + client.delete_hosts(args.tag) + elif args.add_name_servers: + if not args.tag: + raise ValueError("Tag is required for this operation") + client.add_name_servers(args.tag, args.name_server) + elif args.delete_name_servers: + if not args.tag: + raise ValueError("Tag is required for this operation") + client.delete_name_servers(args.tag) + elif args.set_host_name: + client.set_host_name(args.host_name, args.domain_name, args.search_domain) + else: + raise ValueError("Operation required") + +except ValueError as e: + print("Incorrect options: {0}".format(e)) + sys.exit(1) +except vyos.hostsd_client.VyOSHostsdError as e: + print("Server returned an error: {0}".format(e)) + sys.exit(1) + |