Revert "Fixes: T1262 - dhcp requested WAN ip address doesn't get search parameter in /etc/resolv.conf"

This reverts commit 1a384ed21f1777faaef653f9d1e3d9c05542fdc8.

1 files changed, 64 insertions, 202 deletions

diff --git a/src/conf_mode/host_name.py b/src/conf_mode/host_name.py
index 27e2d9170..030735215 100755
--- a/src/conf_mode/host_name.py
+++ b/src/conf_mode/host_name.py
@@ -24,236 +24,98 @@ import os
 import re
 import sys
 import subprocess
-import copy
-import jinja2
-import glob
 
 from vyos.config import Config
 from vyos import ConfigError
 
-config_file_hosts = '/etc/hosts'
-config_file_resolv = '/etc/resolv.conf'
 
-config_tmpl_hosts = """
-### Autogenerated by host_name.py ###
-127.0.0.1       localhost {{ hostname }}{% if domain_name %}.{{ domain_name }}{% endif %}
+hosts_file = '/etc/hosts'
+hostname_regex = re.compile("^[A-Za-z0-9][-.A-Za-z0-9]*[A-Za-z0-9]$")
+local_addr = '127.0.1.1' # NOSONAR
 
-# 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
-
-# static hostname mappings
-{%- if static_host_mapping['hostnames'] %}
-{% for hn in static_host_mapping['hostnames'] -%}
-{{static_host_mapping['hostnames'][hn]['ipaddr']}}\t{{static_host_mapping['hostnames'][hn]['alias']}}\t{{hn}}
-{% endfor -%}
-{%- endif %}
-
-### modifications from other scripts should be added below
-
-"""
-
-config_tmpl_resolv = """
-### Autogenerated by host_name.py ###
-{% for ns in nameserver -%}
-nameserver {{ ns }}
-{% endfor -%}
-
-{%- if domain_name %}
-domain {{ domain_name }}
-{%- endif %}
-
-{%- if domain_search %}
-search {{ domain_search | join(" ") }}
-{%- endif %}
-
-"""
-
-# borrowed from: https://github.com/donjajo/py-world/blob/master/resolvconfReader.py, THX!
-def get_resolvers(file):
-  resolvers = []
-  try:
-    with open(file, 'r') as resolvconf:
-      for line in resolvconf.readlines():
-        line = line.split('#',1)[0];
-        line = line.rstrip();
-        if 'nameserver' in line:
-          resolvers.append(line.split()[1])
-      return resolvers
-  except IOError:
-    return []
-
-def get_dhcp_search_doms(file):
-  search_doms = []
-  try:
-    with open(file, 'r') as resolvconf:
-      for line in resolvconf.readlines():
-        line = line.split('#',1)[0];
-        line = line.rstrip();
-        if 'search' in line:
-          return re.sub('^search','',line).lstrip().split()
-  except IOError:
-    return []
-
-default_config_data = {
-    'hostname': 'vyos',
-    'domain_name': '',
-    'domain_search': [],
-    'nameserver': [],
-    'no_dhcp_ns': False
-}
 
 def get_config():
-  conf = Config()
-  hosts = copy.deepcopy(default_config_data)
+    """Get configuration"""
+    conf = Config()
 
-  hosts['hostname'] = conf.return_value("system host-name")
-  hosts['domain_name'] = conf.return_value("system domain-name")
+    hostname = conf.return_value("system host-name")
+    domain = conf.return_value("system domain-name")
 
-  if hosts['domain_name']:
-    hosts['domain_search'].append(hosts['domain_name'])
+    # No one likes fixups, but we really don't want VyOS fail to boot
+    # if hostname is not in the config
+    if not hostname:
+        hostname = "vyos"
 
-  for search in conf.return_values("system domain-search domain"):
-    hosts['domain_search'].append(search)
+    if domain:
+        fqdn = "{0}.{1}".format(hostname, domain)
+    else:
+        fqdn = hostname
 
-  hosts['nameserver'] = conf.return_values("system name-server")
-  hosts['no_dhcp_ns'] = conf.exists('system disable-dhcp-nameservers')
+    return {"hostname": hostname, "domain": domain, "fqdn": fqdn}
 
-  ## system static-host-mapping
-  hosts['static_host_mapping'] = { 'hostnames'  : {}}
-
-  if conf.exists('system static-host-mapping host-name'):
-    for hn in conf.list_nodes('system static-host-mapping host-name'):
-      hosts['static_host_mapping']['hostnames'][hn] = {
-        'ipaddr'  : conf.return_value('system static-host-mapping host-name ' + hn + ' inet'),
-        'alias'   : '' 
-      }
-      
-      if conf.exists('system static-host-mapping host-name ' + hn + ' alias'):
-        a = conf.return_values('system static-host-mapping host-name ' + hn + ' alias')
-        hosts['static_host_mapping']['hostnames'][hn]['alias'] = " ".join( conf.return_values('system static-host-mapping host-name ' + hn + ' alias') )
-
-  return hosts
 
 def verify(config):
-  if config is None:
-    return None
+    """Verify configuration"""
+    # check for invalid host
 
-  # pattern $VAR(@) "^[[:alnum:]][-.[:alnum:]]*[[:alnum:]]$" ; "invalid host name $VAR(@)"
-  hostname_regex = re.compile("^[A-Za-z0-9][-.A-Za-z0-9]*[A-Za-z0-9]$")
-  if not hostname_regex.match(config['hostname']):
-    raise ConfigError('Invalid host name ' + config["hostname"])
+    # pattern $VAR(@) "^[[:alnum:]][-.[:alnum:]]*[[:alnum:]]$" ; "invalid host name $VAR(@)"
+    if not hostname_regex.match(config["hostname"]):
+        raise ConfigError('Invalid host name ' + config["hostname"])
 
-  # pattern $VAR(@) "^.{1,63}$" ; "invalid host-name length"
-  length = len(config['hostname'])
-  if length < 1 or length > 63:
-    raise ConfigError('Invalid host-name length, must be less than 63 characters')
+    # pattern $VAR(@) "^.{1,63}$" ; "invalid host-name length"
+    length = len(config["hostname"])
+    if length < 1 or length > 63:
+        raise ConfigError(
+            'Invalid host-name length, must be less than 63 characters')
 
-  # The search list is currently limited to six domains with a total of 256 characters.
-  # https://linux.die.net/man/5/resolv.conf
-  if len(config['domain_search']) > 6:
-    raise ConfigError('The search list is currently limited to six domains')
-
-  tmp = ' '.join(config['domain_search'])
-  if len(tmp) > 256:
-    raise ConfigError('The search list is currently limited to 256 characters')
-
-  # static mappings alias hostname
-  if config['static_host_mapping']['hostnames']:
-    for hn in config['static_host_mapping']['hostnames']:
-      if not config['static_host_mapping']['hostnames'][hn]['ipaddr']:
-        raise ConfigError('IP address required for ' + hn)
-      for hn_alias in config['static_host_mapping']['hostnames'][hn]['alias'].split(' '):
-        if not hostname_regex.match(hn_alias) and len (hn_alias) !=0:
-          raise ConfigError('Invalid hostname alias ' + hn_alias)
-
-  return None
-
-def generate(config):
-  if config is None:
     return None
 
-  # If "system disable-dhcp-nameservers" is __configured__ all DNS resolvers
-  # received via dhclient should not be added into the final 'resolv.conf'.
-  #
-  # We iterate over every resolver file and retrieve the received nameservers
-  # for later adjustment of the system nameservers
-  dhcp_ns = []
-  for file in glob.glob('/etc/resolv.conf.dhclient-new*'):
-    for r in get_resolvers(file):
-      dhcp_ns.append(r)
-
-  if not config['no_dhcp_ns']:
-    config['nameserver'] += dhcp_ns
-    for file in glob.glob('/etc/resolv.conf.dhclient-new*'):
-      config['domain_search'] = get_dhcp_search_doms(file)
-
-  # We have third party scripts altering /etc/hosts, too.
-  # One example are the DHCP hostname update scripts thus we need to cache in
-  # every modification first - so changing domain-name, domain-search or hostname
-  # during runtime works
-  old_hosts = ""
-  with open(config_file_hosts, 'r') as f:
-    # Skips text before the beginning of our marker.
-    # NOTE: Marker __MUST__ match the one specified in config_tmpl_hosts
-    for line in f:
-      if line.strip() == '### modifications from other scripts should be added below':
-        break
-
-    for line in f:
-      # This additional line.strip() filters empty lines
-      if line.strip():
-        old_hosts += line
 
-  # Add an additional newline
-  old_hosts += '\n'
-
-  tmpl = jinja2.Template(config_tmpl_hosts)
-  config_text = tmpl.render(config)
-
-  with open(config_file_hosts, 'w') as f:
-    f.write(config_text)
-    f.write(old_hosts)
+def generate(config):
+    """Generate configuration files"""
+    # read the hosts file
+    with open(hosts_file, 'r') as f:
+        hosts = f.read()
+
+    # get the current hostname
+    old_hostname = subprocess.check_output(['hostname']).decode().strip()
+
+    # replace the local host line
+    vyos_host_line_re = re.compile(r"({}\s+{}.*)".format(local_addr, old_hostname))
+    vyos_host_line = "{}\t{} # VyOS entry\n".format(local_addr, config["fqdn"])
+    if re.search(vyos_host_line_re, hosts):
+        hosts = re.sub(vyos_host_line_re, vyos_host_line, hosts)
+    else:
+        # On boot (or after errors), the /etc/hosts file has no line for vyos hostname,
+        # so we have to add it
+        hosts = "{0}\n{1}".format(hosts, vyos_host_line)
+
+    with open(hosts_file, 'w') as f:
+        f.write(hosts)
 
-  tmpl = jinja2.Template(config_tmpl_resolv)
-  config_text = tmpl.render(config)
-  with open(config_file_resolv, 'w') as f:
-    f.write(config_text)
+    return None
 
-  return None
 
 def apply(config):
-  if config is None:
-    return None
-
-  fqdn = config['hostname']
-  if config['domain_name']:
-    fqdn += '.' + config['domain_name']
+    """Apply configuration"""
+    os.system("hostnamectl set-hostname --static {0}".format(config["fqdn"]))
 
-  os.system("hostnamectl set-hostname --static {0}".format(fqdn))
+    # Restart services that use the hostname
+    os.system("systemctl restart rsyslog.service")
 
-  # Restart services that use the hostname
-  os.system("systemctl restart rsyslog.service")
+    # If SNMP is running, restart it too
+    if os.system("pgrep snmpd > /dev/null") == 0:
+        os.system("systemctl restart snmpd.service")
 
-  # If SNMP is running, restart it too
-  if os.system("pgrep snmpd > /dev/null") == 0:
-    os.system("systemctl restart snmpd.service")
-  
-  # restart pdns if it is used
-  if os.system("/usr/bin/rec_control ping >/dev/null 2>&1") == 0:
-    os.system("/etc/init.d/pdns-recursor restart >/dev/null")
+    return None
 
-  return None
 
 if __name__ == '__main__':
-  try:
-    c = get_config()
-    verify(c)
-    generate(c)
-    apply(c)
-  except ConfigError as e:
-    print(e)
-    sys.exit(1)
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        sys.exit(1)