Improve new dig() helper, and use it in dnsrecords diagnosis as well

This commit is contained in:
Alexandre Aubin 2020-04-27 17:24:57 +02:00
parent c6c85556ac
commit 17d3ec5ad3
3 changed files with 42 additions and 19 deletions

View file

@ -2,9 +2,9 @@
import os
from moulinette.utils.process import check_output
from moulinette.utils.filesystem import read_file
from yunohost.utils.network import dig
from yunohost.diagnosis import Diagnoser
from yunohost.domain import domain_list, _build_dns_conf, _get_maindomain
@ -100,20 +100,14 @@ class DNSRecordsDiagnoser(Diagnoser):
yield output
def get_current_record(self, domain, name, type_):
if name == "@":
command = "dig +short @%s %s %s" % (self.resolver, type_, domain)
else:
command = "dig +short @%s %s %s.%s" % (self.resolver, type_, name, domain)
# FIXME : gotta handle case where this command fails ...
# e.g. no internet connectivity (dependency mechanism to good result from 'ip' diagosis ?)
# or the resolver is unavailable for some reason
output = check_output(command).strip().split("\n")
if len(output) == 0 or not output[0]:
query = "%s.%s" % (name, domain) if name != "@" else domain
success, answers = dig(query, type_, resolvers="force_external")
if success != "ok":
return None
elif len(output) == 1:
return output[0]
else:
return output
return answers[0] if len(answers) == 1 else answers
def current_record_match_expected(self, r):
if r["value"] is not None and r["current"] is None:

View file

@ -164,7 +164,7 @@ class MailDiagnoser(Diagnoser):
query = subdomain + '.' + blacklist['dns_server']
# Do the DNS Query
status, answers = dig(query, 'A')
status, _ = dig(query, 'A')
if status != 'ok':
continue

View file

@ -25,6 +25,7 @@ import dns.resolver
from moulinette.utils.network import download_text
from moulinette.utils.process import check_output
from moulinette.utils.filesystem import read_file
logger = logging.getLogger('yunohost.utils.network')
@ -85,22 +86,50 @@ def get_gateway():
return addr.popitem()[1] if len(addr) == 1 else None
def dig(qname, rdtype="A", timeout=5, resolvers=["127.0.0.1"], edns_size=1500):
# Lazy dev caching to avoid re-reading the file multiple time when calling
# dig() often during same yunohost operation
external_resolvers_ = []
def external_resolvers():
global external_resolvers_
if not external_resolvers_:
resolv_dnsmasq_conf = read_file("/etc/resolv.dnsmasq.conf").split("\n")
external_resolvers_ = [r.split(" ")[1] for r in resolv_dnsmasq_conf if r.startswith("nameserver")]
return external_resolvers_
def dig(qname, rdtype="A", timeout=5, resolvers="local", edns_size=1500, full_answers=False):
"""
Do a quick DNS request and avoid the "search" trap inside /etc/resolv.conf
"""
if resolvers == "local":
resolvers = ["127.0.0.1"]
elif resolvers == "force_external":
resolvers = external_resolvers()
else:
assert isinstance(resolvers, list)
resolver = dns.resolver.Resolver(configure=False)
resolver.use_edns(0, 0, edns_size)
resolver.nameservers = resolvers
resolver.timeout = timeout
try:
answers = resolver.query(qname, rdtype)
except (dns.resolver.NXDOMAIN, dns.resolver.NoNameservers, dns.resolver.NoAnswer,
dns.exception.Timeout) as e:
return ("nok", e.__class__.__name__, e)
except (dns.resolver.NXDOMAIN,
dns.resolver.NoNameservers,
dns.resolver.NoAnswer,
dns.exception.Timeout) as e:
return ("nok", (e.__class__.__name__, e))
return ("ok", [(answer.to_text(), answer) for answer in answers])
if not full_answers:
answers = [answer.to_text() for answer in answers]
return ("ok", answers)
def _extract_inet(string, skip_netmask=False, skip_loopback=True):