From f830f450c0c5818090eba9f9f0e0cec5551a1cef Mon Sep 17 00:00:00 2001
From: Fraser Tweedale <ftweedal@redhat.com>
Date: Thu, 30 May 2019 20:57:10 +1000
Subject: [PATCH] Handle missing LWCA certificate or chain
If lightweight CA key replication has not completed, requests for
the certificate or chain will return 404**. This can occur in
normal operation, and should be a temporary condition. Detect this
case and handle it by simply omitting the 'certificate' and/or
'certificate_out' fields in the response, and add a warning message
to the response.
Also update the client-side plugin that handles the
--certificate-out option. Because the CLI will automatically print
the warning message, if the expected field is missing from the
response, just ignore it and continue processing.
** after the Dogtag NullPointerException gets fixed!
Part of: https://pagure.io/freeipa/issue/7964
Reviewed-By: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Fraser Tweedale <ftweedal@redhat.com>
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>
Reviewed-By: Rob Crittenden <rcritten@redhat.com>
---
ipaclient/plugins/ca.py | 19 +++++++++++---
ipalib/messages.py | 9 +++++++
ipaserver/plugins/ca.py | 57 +++++++++++++++++++++++++++++++----------
3 files changed, 68 insertions(+), 17 deletions(-)
diff --git a/ipaclient/plugins/ca.py b/ipaclient/plugins/ca.py
index f0e7d5ced0d3d9318e34aba84cbc37cf42b9410d..ab47ae85df398e1dc40191691a26639eb3772493 100644
--- a/ipaclient/plugins/ca.py
+++ b/ipaclient/plugins/ca.py
@@ -33,13 +33,24 @@ class WithCertOutArgs(MethodOverride):
error=str(e))
result = super(WithCertOutArgs, self).forward(*keys, **options)
+
if filename:
+ # if result certificate / certificate_chain not present in result,
+ # it means Dogtag did not provide it (probably due to LWCA key
+ # replication lag or failure. The server transmits a warning
+ # message in this case, which the client automatically prints.
+ # So in this section we just ignore it and move on.
+ certs = None
if options.get('chain', False):
- certs = result['result']['certificate_chain']
+ if 'certificate_chain' in result['result']:
+ certs = result['result']['certificate_chain']
else:
- certs = [base64.b64decode(result['result']['certificate'])]
- certs = (x509.load_der_x509_certificate(cert) for cert in certs)
- x509.write_certificate_list(certs, filename)
+ if 'certificate' in result['result']:
+ certs = [base64.b64decode(result['result']['certificate'])]
+ if certs:
+ x509.write_certificate_list(
+ (x509.load_der_x509_certificate(cert) for cert in certs),
+ filename)
return result
diff --git a/ipalib/messages.py b/ipalib/messages.py
index 9e2c990d6db8ee41daf3fba6085eed8355dccbe7..646662795648b5a44a5ce25b7610982d5500cfac 100644
--- a/ipalib/messages.py
+++ b/ipalib/messages.py
@@ -487,6 +487,15 @@ class FailedToAddHostDNSRecords(PublicMessage):
"%(reason)s")
+class LightweightCACertificateNotAvailable(PublicMessage):
+ """
+ **13031** Certificate is not available
+ """
+ errno = 13031
+ type = "error"
+ format = _("The certificate for %(ca)s is not available on this server.")
+
+
def iter_messages(variables, base):
"""Return a tuple with all subclasses
"""
diff --git a/ipaserver/plugins/ca.py b/ipaserver/plugins/ca.py
index 88e7ec2a9f50a3c4f90947c8e3d38e327627a878..c8f1630c65d55ee9e820ea50ef34e08f92c66f4a 100644
--- a/ipaserver/plugins/ca.py
+++ b/ipaserver/plugins/ca.py
@@ -6,7 +6,7 @@ import base64
import six
-from ipalib import api, errors, output, Bytes, DNParam, Flag, Str
+from ipalib import api, errors, messages, output, Bytes, DNParam, Flag, Str
from ipalib.constants import IPA_CA_CN
from ipalib.plugable import Registry
from ipapython.dn import ATTR_NAME_BY_OID
@@ -163,28 +163,53 @@ class ca(LDAPObject):
def set_certificate_attrs(entry, options, want_cert=True):
+ """
+ Set certificate attributes into the entry. Depending on
+ options, this may contact Dogtag to retrieve certificate or
+ chain. If the retrieval fails with 404 (which can occur under
+ normal operation due to lightweight CA key replication delay),
+ return a message object that should be set in the response.
+
+ """
try:
ca_id = entry['ipacaid'][0]
except KeyError:
- return
+ return None
full = options.get('all', False)
want_chain = options.get('chain', False)
want_data = want_cert or want_chain or full
if not want_data:
- return
+ return None
+
+ msg = None
with api.Backend.ra_lightweight_ca as ca_api:
if want_cert or full:
- der = ca_api.read_ca_cert(ca_id)
- entry['certificate'] = base64.b64encode(der).decode('ascii')
+ try:
+ der = ca_api.read_ca_cert(ca_id)
+ entry['certificate'] = base64.b64encode(der).decode('ascii')
+ except errors.HTTPRequestError as e:
+ if e.status == 404: # pylint: disable=no-member
+ msg = messages.LightweightCACertificateNotAvailable(
+ ca=entry['cn'][0])
+ else:
+ raise e
if want_chain or full:
- pkcs7_der = ca_api.read_ca_chain(ca_id)
- certs = x509.pkcs7_to_certs(pkcs7_der, x509.DER)
- ders = [cert.public_bytes(x509.Encoding.DER) for cert in certs]
- entry['certificate_chain'] = ders
-
+ try:
+ pkcs7_der = ca_api.read_ca_chain(ca_id)
+ certs = x509.pkcs7_to_certs(pkcs7_der, x509.DER)
+ ders = [cert.public_bytes(x509.Encoding.DER) for cert in certs]
+ entry['certificate_chain'] = ders
+ except errors.HTTPRequestError as e:
+ if e.status == 404: # pylint: disable=no-member
+ msg = messages.LightweightCACertificateNotAvailable(
+ ca=entry['cn'][0])
+ else:
+ raise e
+
+ return msg
@register()
class ca_find(LDAPSearch):
@@ -198,7 +223,9 @@ class ca_find(LDAPSearch):
result = super(ca_find, self).execute(*keys, **options)
if not options.get('pkey_only', False):
for entry in result['result']:
- set_certificate_attrs(entry, options, want_cert=False)
+ msg = set_certificate_attrs(entry, options, want_cert=False)
+ if msg:
+ self.add_message(msg)
return result
@@ -220,7 +247,9 @@ class ca_show(LDAPRetrieve):
def execute(self, *keys, **options):
ca_enabled_check(self.api)
result = super(ca_show, self).execute(*keys, **options)
- set_certificate_attrs(result['result'], options)
+ msg = set_certificate_attrs(result['result'], options)
+ if msg:
+ self.add_message(msg)
return result
@@ -284,7 +313,9 @@ class ca_add(LDAPCreate):
return dn
def post_callback(self, ldap, dn, entry_attrs, *keys, **options):
- set_certificate_attrs(entry_attrs, options)
+ msg = set_certificate_attrs(entry_attrs, options)
+ if msg:
+ self.add_message(msg)
return dn
--
2.20.1