add support for ipv6 slaac

etc/network/ifupdown2/addons.conf

@@ -15,6 +15,7 @@ pre-up,mstpctl
 pre-up,tunnel
 pre-up,vrf
 pre-up,ethtool
+pre-up,auto
 pre-up,address
 up,dhcp
 up,address
@@ -28,6 +29,7 @@ pre-down,usercmds
 pre-down,vxrd
 pre-down,dhcp
 down,ppp
+down,auto
 down,addressvirtual
 down,address
 down,usercmds

ifupdown2/addons/address.py

@@ -188,6 +188,19 @@ class address(AddonWithIpBlackList, moduleBase):
                 'default': 'off',
                 'example': ['arp-accept on']
             },
+            'accept-ra': {
+                'help': 'accept ipv6 router advertisement',
+                'validvals': ['0', '1', '2'],
+                'default': '0',
+                'example': ['accept-ra 1']
+            },
+            'autoconf': {
+                'help': 'enable ipv6 slaac autoconfiguration',
+                'validvals': ['0', '1'],
+                'default': '0',
+                'example': ['autoconf 1']
+            },
+
         }
     }
 
@@ -256,6 +269,16 @@ def __init__(self, *args, **kargs):
             attr="check_l3_svi_ip_forwarding")
         )
 
+        try:
+            self.default_accept_ra = str(self.sysctl_get('net.ipv6.conf.all.accept_ra'))
+        except Exception:
+            self.default_accept_ra = 1
+
+        try:
+            self.default_autoconf = str(self.sysctl_get('net.ipv6.conf.all.autoconf'))
+        except Exception:
+            self.default_autoconf = 1
+
     def __policy_get_default_mtu(self):
         default_mtu = policymanager.policymanager_api.get_attr_default(
             module_name=self.__class__.__name__,
@@ -627,21 +650,31 @@ def process_addresses(self, ifaceobj, ifaceobj_getfunc=None, force_reapply=False
                 if force_reapply:
                     self.__add_ip_addresses_with_attributes(ifaceobj, ifname, user_config_ip_addrs_list)
                 return
+
+            purge_dynamic_v6_addresses = True
+            running_autoconf = self.cache.get_link_inet6_autoconf(ifaceobj)
+            if running_autoconf == '1' and not squash_addr_config:
+                purge_dynamic_v6_addresses = False
+
             try:
-                # if primary address is not same, there is no need to keep any, reset all addresses.
-                if ordered_user_configured_ips and running_ip_addrs and ordered_user_configured_ips[0] != running_ip_addrs[0]:
-                    self.logger.info("%s: primary ip changed (from %s to %s) we need to purge all ip addresses and re-add them"
-                                     % (ifname, ordered_user_configured_ips[0], running_ip_addrs[0]))
-                    skip_addrs = []
+                # if primary ipv4 address is not same, there is no need to keep any, reset all ipv4 addresses.
+                if user_ip4 and running_ip_addrs and running_ip_addrs[0].version == 4 and user_ip4[0] != running_ip_addrs[0]:
+                    self.logger.info("%s: primary ipv4 changed (from %s to %s) we need to purge all ipv4 addresses and re-add them"
+                                     % (ifname, user_ip4[0], running_ip_addrs[0]))
+                    skip_addrs = user_ip6
                 else:
                     skip_addrs = ordered_user_configured_ips
 
                 if anycast_ip:
                     skip_addrs.append(anycast_ip)
 
+                ip_flags = self.cache.get_ip_addresses_flags(ifname)
                 for addr in running_ip_addrs:
                     if addr in skip_addrs:
                         continue
+                    # don't purge dynamic ipv6 ip if autoconf is enabled
+                    if addr.version == 6 and not purge_dynamic_v6_addresses and addr in ip_flags and not ip_flags[addr] & 0x80:
+                        continue
                     self.netlink.addr_del(ifname, addr)
             except Exception as e:
                 self.log_warn(str(e))
@@ -872,7 +905,9 @@ def _set_bridge_forwarding(self, ifaceobj):
         netconf_ipv4_forwarding = self.cache.get_netconf_forwarding(socket.AF_INET, ifname)
         netconf_ipv6_forwarding = self.cache.get_netconf_forwarding(socket.AF_INET6, ifname)
 
-        if not ifaceobj.upperifaces and not ifaceobj.get_attr_value('address') and (ifaceobj.addr_method and "dhcp" not in ifaceobj.addr_method):
+        if ( not ifaceobj.upperifaces and not ifaceobj.get_attr_value('address') and
+             ifaceobj.addr_method and "dhcp" not in ifaceobj.addr_method and "auto" not in ifaceobj.addr_method):
+
             if netconf_ipv4_forwarding:
                 self.sysctl_write_forwarding_value_to_proc(ifname, "ipv4", 0)
             if netconf_ipv6_forwarding:
@@ -886,6 +921,43 @@ def _set_bridge_forwarding(self, ifaceobj):
     def sysctl_write_forwarding_value_to_proc(self, ifname, family, value):
         self.write_file("/proc/sys/net/%s/conf/%s/forwarding" % (family, ifname), "%s\n" % value)
 
+    def _sysctl_slaac(self, ifaceobj):
+        addr_method = ifaceobj.addr_method
+        if addr_method not in ["auto"]:
+
+            try:
+                running_accept_ra = self.cache.get_link_inet6_accept_ra(ifaceobj)
+                if running_accept_ra == '':
+                    running_accept_ra = self.default_accept_ra
+                accept_ra = ifaceobj.get_attr_value_first('accept-ra')
+                if accept_ra is None:
+                    accept_ra = self.default_accept_ra
+
+                if running_accept_ra != accept_ra:
+                    self.sysctl_set('net.ipv6.conf.%s.accept_ra'
+                                    %('/'.join(ifaceobj.name.split("."))),
+                                    accept_ra)
+                    self.cache.update_link_inet6_accept_ra(ifaceobj.name, accept_ra)
+
+                running_autoconf = self.cache.get_link_inet6_autoconf(ifaceobj)
+                if running_autoconf == '':
+                    running_autoconf = self.default_autoconf
+                autoconf = ifaceobj.get_attr_value_first('autoconf')
+                if autoconf is None:
+                    autoconf = self.default_autoconf
+
+                if running_autoconf != autoconf:
+                    self.sysctl_set('net.ipv6.conf.%s.autoconf'
+                                    %('/'.join(ifaceobj.name.split("."))),
+                                    autoconf)
+                    self.cache.update_link_inet6_autoconf(ifaceobj.name, autoconf)
+
+            except Exception as e:
+                if not setting_default_value:
+                    ifaceobj.status = ifaceStatus.ERROR
+                    self.logger.error('%s: %s' %(ifaceobj.name, str(e)))
+
+
     def _sysctl_config(self, ifaceobj):
         setting_default_value = False
         mpls_enable = ifaceobj.get_attr_value_first('mpls-enable');
@@ -912,6 +984,7 @@ def _sysctl_config(self, ifaceobj):
 
         if (ifaceobj.link_kind & ifaceLinkKind.BRIDGE):
             self._set_bridge_forwarding(ifaceobj)
+            self._sysctl_slaac(ifaceobj)
             return
         if not self.syntax_check_sysctls(ifaceobj):
             return
@@ -979,6 +1052,8 @@ def _sysctl_config(self, ifaceobj):
                        ifaceobj.status = ifaceStatus.ERROR
                        self.logger.error('%s: %s' %(ifaceobj.name, str(e)))
 
+        self._sysctl_slaac(ifaceobj)
+
     def process_mtu(self, ifaceobj, ifaceobj_getfunc):
 
         if ifaceobj.link_privflags & ifaceLinkPrivFlags.OPENVSWITCH:
@@ -1016,7 +1091,7 @@ def up_ipv6_addrgen(self, ifaceobj):
             # no need to go further during perfmode (boot)
             return
 
-        if not user_configured_ipv6_addrgen and ifaceobj.addr_method in ["dhcp", "ppp"]:
+        if not user_configured_ipv6_addrgen and ifaceobj.addr_method in ["dhcp", "ppp", "auto"]:
             return
 
         if not user_configured_ipv6_addrgen:
@@ -1213,7 +1288,7 @@ def _down(self, ifaceobj, ifaceobj_getfunc=None):
             if not self.cache.link_exists(ifaceobj.name):
                 return
             addr_method = ifaceobj.addr_method
-            if addr_method not in ["dhcp", "ppp"]:
+            if addr_method not in ["dhcp", "ppp", "auto"]:
                 if ifaceobj.get_attr_value_first('address-purge')=='no':
                     addrlist = ifaceobj.get_attr_value('address')
                     for addr in addrlist or []:
@@ -1326,6 +1401,22 @@ def _query_sysctl(self, ifaceobj, ifaceobjcurr):
             ifaceobjcurr.update_config_with_status('mpls-enable',
                                                    running_mpls_enable,
                                             mpls_enable != running_mpls_enable)
+
+        accept_ra = ifaceobj.get_attr_value_first('accept-ra')
+        if accept_ra:
+            running_accept_ra = self.cache.get_link_inet6_accept_ra(ifaceobj)
+
+            ifaceobjcurr.update_config_with_status('accept_ra',
+                                                   running_accept_ra,
+                                            accept_ra != running_accept_ra)
+
+        autoconf = ifaceobj.get_attr_value_first('autoconf')
+        if autoconf:
+            running_autoconf = self.cache.get_link_inet6_autoconf(ifaceobj)
+
+            ifaceobjcurr.update_config_with_status('autoconf',
+                                                   running_autoconf,
+                                            autoconf != running_autoconf)
         return
 
     def query_check_ipv6_addrgen(self, ifaceobj, ifaceobjcurr):
@@ -1380,7 +1471,7 @@ def _query_check(self, ifaceobj, ifaceobjcurr, ifaceobj_getfunc=None):
 
     def _query_check_address(self, ifaceobj, ifaceobjcurr, ifaceobj_getfunc):
         """ ifquery-check: attribute: "address" """
-        if ifaceobj.addr_method in ["dhcp", "ppp"]:
+        if ifaceobj.addr_method in ["dhcp", "ppp", "auto"]:
             return
 
         if ifaceobj_getfunc:

ifupdown2/addons/auto.py

@@ -0,0 +1,168 @@
+#!/usr/bin/env python3
+#
+
+import re
+import time
+import socket
+
+try:
+    from ifupdown2.lib.addon import Addon
+    from ifupdown2.lib.log import LogManager
+
+    import ifupdown2.ifupdown.policymanager as policymanager
+    import ifupdown2.ifupdown.ifupdownflags as ifupdownflags
+
+    from ifupdown2.ifupdown.iface import *
+    from ifupdown2.ifupdown.utils import utils
+
+    from ifupdown2.ifupdownaddons.modulebase import moduleBase
+except (ImportError, ModuleNotFoundError):
+    from lib.addon import Addon
+    from lib.log import LogManager
+
+    import ifupdown.policymanager as policymanager
+    import ifupdown.ifupdownflags as ifupdownflags
+
+    from ifupdown.iface import *
+    from ifupdown.utils import utils
+
+    from ifupdownaddons.modulebase import moduleBase
+
+
+class auto(Addon, moduleBase):
+    """ ifupdown2 addon module to configure slaac on inet6 interface """
+
+    def __init__(self, *args, **kargs):
+        Addon.__init__(self)
+        moduleBase.__init__(self, *args, **kargs)
+
+    def syntax_check(self, ifaceobj, ifaceobj_getfunc):
+        return self.is_auto_allowed_on(ifaceobj, syntax_check=True)
+
+    def is_auto_allowed_on(self, ifaceobj, syntax_check):
+        if ifaceobj.addr_method and 'auto' in ifaceobj.addr_method:
+            return utils.is_addr_ip_allowed_on(ifaceobj, syntax_check=True)
+        return True
+
+    def _up(self, ifaceobj):
+
+        if ifaceobj.link_privflags & ifaceLinkPrivFlags.KEEP_LINK_DOWN:
+            self.logger.info("%s: skipping auto configuration: link-down yes" % ifaceobj.name)
+            return
+
+        try:
+            if 'inet6' in ifaceobj.addr_family:
+                running_accept_ra = self.cache.get_link_inet6_accept_ra(ifaceobj)
+                if running_accept_ra != '2':
+                    accept_ra = '2'
+                    self.sysctl_set('net.ipv6.conf.%s.accept_ra'
+                                    %('/'.join(ifaceobj.name.split("."))),
+                                    accept_ra)
+                    self.cache.update_link_inet6_accept_ra(ifaceobj.name, accept_ra)
+
+                running_autoconf = self.cache.get_link_inet6_autoconf(ifaceobj)
+                if running_autoconf != '1':
+                    autoconf = '1'
+                    self.sysctl_set('net.ipv6.conf.%s.autoconf'
+                                    %('/'.join(ifaceobj.name.split("."))),
+                                    autoconf)
+                    self.cache.update_link_inet6_autoconf(ifaceobj.name, autoconf)
+
+        except Exception as e:
+            self.logger.error("%s: %s" % (ifaceobj.name, str(e)))
+            ifaceobj.set_status(ifaceStatus.ERROR)
+
+    def _down(self, ifaceobj):
+        if 'inet6' in ifaceobj.addr_family:
+            self.cache.force_address_flush_family(ifaceobj.name, socket.AF_INET6)
+        self.netlink.link_down(ifaceobj.name)
+
+    def _query_check(self, ifaceobj, ifaceobjcurr):
+        if not self.cache.link_exists(ifaceobj.name):
+            return
+        ifaceobjcurr.addr_family = ifaceobj.addr_family
+        ifaceobjcurr.addr_method = 'auto'
+
+        inet6conf = self.cache.get_link_inet6_conf(ifaceobj.name)
+        if inet6conf['accept_ra'] == 2 and inet6conf['autoconf'] == 1:
+            ifaceobjcurr.status = ifaceStatus.SUCCESS
+        else:
+            ifaceobjcurr.status = ifaceStatus.ERROR
+
+    def _query_running(self, ifaceobjrunning):
+        pass
+
+    _run_ops = {'pre-up' : _up,
+               'up' : _up,
+               'down' : _down,
+               'pre-down' : _down,
+               'query-checkcurr' : _query_check,
+               'query-running' : _query_running }
+
+    def get_ops(self):
+        """ returns list of ops supported by this module """
+        return list(self._run_ops.keys())
+
+    def run(self, ifaceobj, operation, query_ifaceobj=None, **extra_args):
+        """ run dhcp configuration on the interface object passed as argument
+
+        Args:
+            **ifaceobj** (object): iface object
+
+            **operation** (str): any of 'up', 'down', 'query-checkcurr',
+                                 'query-running'
+
+        Kwargs:
+            **query_ifaceobj** (object): query check ifaceobject. This is only
+                valid when op is 'query-checkcurr'. It is an object same as
+                ifaceobj, but contains running attribute values and its config
+                status. The modules can use it to return queried running state
+                of interfaces. status is success if the running state is same
+                as user required state in ifaceobj. error otherwise.
+        """
+        op_handler = self._run_ops.get(operation)
+        if not op_handler:
+            return
+        try:
+            if (operation != 'query-running' and ifaceobj.addr_method != 'auto'):
+                return
+        except Exception:
+            return
+        if not self.is_auto_allowed_on(ifaceobj, syntax_check=False):
+            return
+
+        log_manager = LogManager.get_instance()
+
+        syslog_log_level = logging.INFO
+        disable_syslog_on_exit = None
+
+        if operation in ["up", "down"]:
+            # if syslog is already enabled we shouldn't disable it
+            if log_manager.is_syslog_enabled():
+                # save current syslog level
+                syslog_log_level = log_manager.get_syslog_log_level()
+                # prevent syslog from being disabled on exit
+                disable_syslog_on_exit = False
+            else:
+                # enabling syslog
+                log_manager.enable_syslog()
+                # syslog will be disabled once we are done
+                disable_syslog_on_exit = True
+
+            # update the current syslog handler log level if higher than INFO
+            if syslog_log_level >= logging.INFO:
+                log_manager.set_level_syslog(logging.INFO)
+
+            self.logger.info("%s: enabling syslog for auto configuration" % ifaceobj.name)
+
+        try:
+            if operation == 'query-checkcurr':
+                op_handler(self, ifaceobj, query_ifaceobj)
+            else:
+                op_handler(self, ifaceobj)
+        finally:
+            # disable syslog handler or re-set the proper log-level
+            if disable_syslog_on_exit is True:
+                log_manager.get_instance().disable_syslog()
+            elif disable_syslog_on_exit is False:
+                log_manager.set_level_syslog(syslog_log_level)