configure DNA plugin shared config entries to allow connection with GSSAPI

https://fedorahosted.org/freeipa/ticket/4026

When a replica needs to extend its DNA range, it selects the remote replica with the
larger available range. If there is no replica agreement to that remote replica,
the shared config entry needs to contain the connection method/protocol.
This fix requires 389-ds
 * https://fedorahosted.org/389/ticket/47779
 * https://fedorahosted.org/389/ticket/48362

That are both fixed in 1.3.4.6

Reviewed-By: Martin Babinsky <mbabinsk@redhat.com>

freeipa.spec.in

@@ -130,7 +130,7 @@ Requires: %{name}-client = %{version}-%{release}
 Requires: %{name}-admintools = %{version}-%{release}
 Requires: %{name}-common = %{version}-%{release}
 Requires: python2-ipaserver = %{version}-%{release}
-Requires: 389-ds-base >= 1.3.4.4
+Requires: 389-ds-base >= 1.3.4.6
 Requires: openldap-clients > 2.4.35-4
 Requires: nss >= 3.14.3-12.0
 Requires: nss-tools >= 3.14.3-12.0
@@ -162,7 +162,7 @@ Requires: zip
 Requires: policycoreutils >= 2.1.12-5
 Requires: tar
 Requires(pre): certmonger >= 0.78
-Requires(pre): 389-ds-base >= 1.3.4.4
+Requires(pre): 389-ds-base >= 1.3.4.6
 Requires: fontawesome-fonts
 Requires: open-sans-fonts
 Requires: openssl

ipaserver/install/dsinstance.py

@@ -1261,3 +1261,107 @@ class DsInstance(service.Service):
 
         # check for open secure port 636 from now on
         self.open_ports.append(636)
+
+    def update_dna_shared_config(self, method="SASL/GSSAPI", protocol="LDAP"):
+
+        dna_bind_method = "dnaRemoteBindMethod"
+        dna_conn_protocol = "dnaRemoteConnProtocol"
+        dna_plugin = DN(('cn', 'Distributed Numeric Assignment Plugin'),
+                        ('cn', 'plugins'),
+                        ('cn', 'config'))
+        dna_config_base = DN(('cn', 'posix IDs'), dna_plugin)
+
+        if not self.admin_conn:
+            self.ldap_connect()
+        conn = self.admin_conn
+
+        # Check the plugin is enabled else it is useless to update
+        # the shared entry
+        try:
+            entry = conn.get_entry(dna_plugin)
+            if entry.single_value.get('nsslapd-pluginenabled') == 'off':
+                return
+        except errors.NotFound:
+            root_logger.error("Could not find DNA plugin entry: %s" %
+                              dna_config_base)
+            return
+
+        try:
+            entry = conn.get_entry(dna_config_base)
+        except errors.NotFound:
+            root_logger.error("Could not find DNA config entry: %s" %
+                              dna_config_base)
+            return
+
+        sharedcfgdn = entry.single_value.get("dnaSharedCfgDN")
+        if sharedcfgdn is not None:
+            sharedcfgdn = DN(sharedcfgdn)
+        else:
+            root_logger.error(
+                "Could not find DNA shared config DN in entry: %s" %
+                dna_config_base)
+            return
+
+        #
+        # Update the shared config entry related to that host
+        #
+        # If the shared config entry already exists (like upgrade)
+        # the update occurs immediately without sleep.
+        #
+        # If the shared config entry does not exist (fresh install)
+        # DS server waits for 30s after its startup to create it.
+        # Startup likely occurred few sec before this function is
+        # called so this loop will wait for 30s max.
+        #
+        # In case the server is not able to create the entry
+        # The loop gives a grace period of 60s before logging
+        # the failure to update the shared config entry and return
+        #
+        max_wait = 30
+        for i in range(0, max_wait + 1):
+            try:
+                entries = conn.get_entries(
+                    sharedcfgdn, scope=ldap.SCOPE_ONELEVEL,
+                    filter='dnaHostname=%s' % self.fqdn
+                )
+                break
+            except errors.NotFound:
+                root_logger.debug(
+                    "Unable to find DNA shared config entry for "
+                    "dnaHostname=%s (under %s) so far. Retry in 2 sec." %
+                    (self.fqdn, sharedcfgdn)
+                )
+                time.sleep(2)
+        else:
+            root_logger.error(
+                "Could not get dnaHostname entries in {} seconds".format(
+                    max_wait * 2)
+            )
+            return
+
+        # If there are several entries, all of them will be updated
+        # just log a debug msg. This is likely the result of #5510
+        if len(entries) != 1:
+            root_logger.debug(
+                "%d entries dnaHostname=%s under %s. One expected" %
+                (len(entries), self.fqdn, sharedcfgdn)
+            )
+
+        # time to set the bind method and the protocol in the
+        # shared config entries
+        for entry in entries:
+            mod = []
+            if entry.single_value.get(dna_bind_method) != method:
+                mod.append((ldap.MOD_REPLACE, dna_bind_method, method))
+
+            if entry.single_value.get(dna_conn_protocol) != method:
+                mod.append((ldap.MOD_REPLACE, dna_conn_protocol, protocol))
+
+            if mod:
+                try:
+                    conn.modify_s(entry.dn, mod)
+                except Exception as e:
+                    root_logger.error(
+                        "Failed to set SASL/GSSAPI bind method/protocol "
+                        "in entry {}: {}".format(entry, e)
+                    )

ipaserver/install/server/install.py

@@ -988,6 +988,10 @@ def install(installer):
     service.print_msg("Restarting the web server")
     http.restart()
 
+    # update DNA shared config entry is done as far as possible
+    # from restart to avoid waiting for its creation
+    ds.update_dna_shared_config()
+
     # Set the admin user kerberos password
     ds.change_admin_password(admin_password)
 

ipaserver/install/server/replicainstall.py

@@ -881,6 +881,10 @@ def install(installer):
 
     ds.replica_populate()
 
+    # update DNA shared config entry is done as far as possible
+    # from restart to avoid waiting for its creation
+    ds.update_dna_shared_config()
+
     # Everything installed properly, activate ipa service.
     services.knownservices.ipa.enable()
 
@@ -1457,6 +1461,10 @@ def promote(installer):
 
     ds.replica_populate()
 
+    # update DNA shared config entry is done as far as possible
+    # from restart to avoid waiting for its creation
+    ds.update_dna_shared_config()
+
     custodia.import_dm_password(config.master_host_name)
 
     promote_sssd(config.host_name)

ipaserver/install/server/upgrade.py

@@ -1544,6 +1544,7 @@ def upgrade_configuration():
 
     ds.ldap_connect()
     ds_enable_sidgen_extdom_plugins(ds)
+    ds.update_dna_shared_config()
     ds.ldap_disconnect()
 
     # Now 389-ds is available, run the remaining http tasks