Merge pull request #419 from dhpiggott/improve-dmarc-and-spf-descriptions

Improve DMARC and SPF record descriptions
This commit is contained in:
Joshua Tauberer 2015-05-28 13:06:44 -04:00
commit d3c82d7363
1 changed files with 11 additions and 11 deletions

View File

@ -24,7 +24,7 @@ def get_dns_zones(env):
# What domains should we create DNS zones for? Never create a zone for # What domains should we create DNS zones for? Never create a zone for
# a domain & a subdomain of that domain. # a domain & a subdomain of that domain.
domains = get_dns_domains(env) domains = get_dns_domains(env)
# Exclude domains that are subdomains of other domains we know. Proceed # Exclude domains that are subdomains of other domains we know. Proceed
# by looking at shorter domains first. # by looking at shorter domains first.
zone_domains = set() zone_domains = set()
@ -49,7 +49,7 @@ def get_dns_zones(env):
zonefiles.sort(key = lambda zone : zone_order.index(zone[0]) ) zonefiles.sort(key = lambda zone : zone_order.index(zone[0]) )
return zonefiles return zonefiles
def do_dns_update(env, force=False): def do_dns_update(env, force=False):
# What domains (and their zone filenames) should we build? # What domains (and their zone filenames) should we build?
domains = get_dns_domains(env) domains = get_dns_domains(env)
@ -247,17 +247,17 @@ def build_zone(domain, all_domains, additional_records, env, is_zone=True):
# Append a DMARC record. # Append a DMARC record.
# Skip if the user has set a DMARC record already. # Skip if the user has set a DMARC record already.
if not has_rec("_dmarc", "TXT", prefix="v=DMARC1; "): if not has_rec("_dmarc", "TXT", prefix="v=DMARC1; "):
records.append(("_dmarc", "TXT", 'v=DMARC1; p=quarantine', "Optional. Specifies that mail that does not originate from the box but claims to be from @%s is suspect and should be quarantined by the recipient's mail system." % domain)) records.append(("_dmarc", "TXT", 'v=DMARC1; p=quarantine', "Recommended. Specifies that mail that does not originate from the box but claims to be from @%s or which does not have a valid DKIM signature is suspect and should be quarantined by the recipient's mail system." % domain))
# For any subdomain with an A record but no SPF or DMARC record, add strict policy records. # For any subdomain with an A record but no SPF or DMARC record, add strict policy records.
all_resolvable_qnames = set(r[0] for r in records if r[1] in ("A", "AAAA")) all_resolvable_qnames = set(r[0] for r in records if r[1] in ("A", "AAAA"))
for qname in all_resolvable_qnames: for qname in all_resolvable_qnames:
if not has_rec(qname, "TXT", prefix="v=spf1 "): if not has_rec(qname, "TXT", prefix="v=spf1 "):
records.append((qname, "TXT", 'v=spf1 a mx -all', "Prevents unauthorized use of this domain name for outbound mail by requiring outbound mail to originate from the indicated host(s).")) records.append((qname, "TXT", 'v=spf1 a mx -all', "Recommended. Prevents unauthorized use of this domain name for outbound mail by specifying that only servers pointed to by a parallel A or MX record are valid sources for mail from @%s." % (qname + "." + domain)))
dmarc_qname = "_dmarc" + ("" if qname is None else "." + qname) dmarc_qname = "_dmarc" + ("" if qname is None else "." + qname)
if not has_rec(dmarc_qname, "TXT", prefix="v=DMARC1; "): if not has_rec(dmarc_qname, "TXT", prefix="v=DMARC1; "):
records.append((dmarc_qname, "TXT", 'v=DMARC1; p=reject', "Prevents unauthorized use of this domain name for outbound mail by requiring a valid DKIM signature.")) records.append((dmarc_qname, "TXT", 'v=DMARC1; p=reject', "Recommended. Prevents unauthorized use of this domain name for outbound mail by specifying that the SPF rule should be honoured for mail from @%s." % (qname + "." + domain)))
# Sort the records. The None records *must* go first in the nsd zone file. Otherwise it doesn't matter. # Sort the records. The None records *must* go first in the nsd zone file. Otherwise it doesn't matter.
records.sort(key = lambda rec : list(reversed(rec[0].split(".")) if rec[0] is not None else "")) records.sort(key = lambda rec : list(reversed(rec[0].split(".")) if rec[0] is not None else ""))
@ -325,7 +325,7 @@ def build_sshfp_records():
# Lots of things can go wrong. Don't let it disturb the DNS # Lots of things can go wrong. Don't let it disturb the DNS
# zone. # zone.
pass pass
######################################################################## ########################################################################
def write_nsd_zone(domain, zonefile, records, env, force): def write_nsd_zone(domain, zonefile, records, env, force):
@ -435,7 +435,7 @@ def write_nsd_conf(zonefiles, additional_records, env):
# Write the list of zones to a configuration file. # Write the list of zones to a configuration file.
nsd_conf_file = "/etc/nsd/zones.conf" nsd_conf_file = "/etc/nsd/zones.conf"
nsdconf = "" nsdconf = ""
# Append the zones. # Append the zones.
for domain, zonefile in zonefiles: for domain, zonefile in zonefiles:
nsdconf += """ nsdconf += """
@ -492,7 +492,7 @@ def sign_zone(domain, zonefile, env):
# a new .key file with a DNSSEC record for the specific domain. We # a new .key file with a DNSSEC record for the specific domain. We
# can reuse the same key, but it won't validate without a DNSSEC # can reuse the same key, but it won't validate without a DNSSEC
# record specifically for the domain. # record specifically for the domain.
# #
# Copy the .key and .private files to /tmp to patch them up. # Copy the .key and .private files to /tmp to patch them up.
# #
# Use os.umask and open().write() to securely create a copy that only # Use os.umask and open().write() to securely create a copy that only
@ -691,8 +691,8 @@ def write_custom_dns_config(config, env):
if len(values) == 1: if len(values) == 1:
values = values[0] values = values[0]
dns[qname][rtype] = values dns[qname][rtype] = values
# Write. # Write.
config_yaml = rtyaml.dump(dns) config_yaml = rtyaml.dump(dns)
with open(os.path.join(env['STORAGE_ROOT'], 'dns/custom.yaml'), "w") as f: with open(os.path.join(env['STORAGE_ROOT'], 'dns/custom.yaml'), "w") as f:
f.write(config_yaml) f.write(config_yaml)