summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorThomas Haller <thaller@redhat.com>2019-07-12 11:19:43 +0200
committerThomas Haller <thaller@redhat.com>2019-07-16 10:16:07 +0200
commit15b1304477ed64a10f2be01760d6837ffaaba002 (patch)
tree86ce5aeb96f61472b6c801fc53c0bd1de98f55d2
parent6ea56bc04c772b49b84b74396b5e71ba5ff1a089 (diff)
policy-routing: take ownership of externally configured rules
IP addresses, routes, TC and QDiscs are all tied to a certain interface. So when NetworkManager manages an interface, it can be confident that all related entires should be managed, deleted and modified by NetworkManager. Routing policy rules are global. For that we have NMPRulesManager which keeps track of whether NetworkManager owns a rule. This allows multiple connection profiles to specify the same rule, and NMPRulesManager can consolidate this information to know whether to add or remove the rule. NMPRulesManager would also support to explicitly block a rule by tracking it with negative priority. However that is still unused at the moment. All that devices do is to add rules (track with positive priority) and remove them (untrack) once the profile gets deactivated. As rules are not exclusively owned by NetworkManager, NetworkManager tries not to interfere with rules that it knows nothing about. That means in particular, when NetworkManager starts it will "weakly track" all rules that are present. "weakly track" is mostly interesting for two cases: - when NMPRulesManager had the same rule explicitly tracked (added) by a device, then deactivating the device will leave the rule in place. - when NMPRulesManager had the same rule explicitly blocked (tracked with negative priority), then it would restore the rule when that block gets removed (as said, currently nobody actually does this). Note that when restarting NetworkManager, then the device may stay and the rules kept. However after restart, NetworkManager no longer knows that it previously added this route, so it would weakly track it and never remove them again. That is a problem. Avoid that, by whenever explicitly tracking a rule we also make sure to no longer weakly track it. Most likely this rule was indeed previously managed by NetworkManager. If this was really a rule added by externally, then the user really should choose distinct rule priorities to avoid such conflicts altogether.
-rw-r--r--src/devices/nm-device.c7
-rw-r--r--src/nm-netns.c16
-rw-r--r--src/platform/nmp-rules-manager.c116
-rw-r--r--src/platform/nmp-rules-manager.h5
-rw-r--r--src/platform/tests/test-route.c12
5 files changed, 128 insertions, 28 deletions
diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c
index 6a27469d4..8175456b8 100644
--- a/src/devices/nm-device.c
+++ b/src/devices/nm-device.c
@@ -6618,10 +6618,15 @@ _routing_rules_sync (NMDevice *self,
rule = nm_setting_ip_config_get_routing_rule (s_ip, i);
nm_ip_routing_rule_to_platform (rule, &plrule);
+
+ /* We track this rule, but we also make it explicitly not weakly-tracked
+ * (meaning to untrack NMP_RULES_MANAGER_EXTERN_WEAKLY_TRACKED_USER_TAG at
+ * the same time). */
nmp_rules_manager_track (rules_manager,
&plrule,
10,
- user_tag);
+ user_tag,
+ NMP_RULES_MANAGER_EXTERN_WEAKLY_TRACKED_USER_TAG);
}
}
}
diff --git a/src/nm-netns.c b/src/nm-netns.c
index de822151a..c1ced1534 100644
--- a/src/nm-netns.c
+++ b/src/nm-netns.c
@@ -127,17 +127,27 @@ constructed (GObject *object)
priv->rules_manager = nmp_rules_manager_new (priv->platform);
- /* Weakly track the default rules and rules that were added
- * outside of NetworkManager. */
+ /* Weakly track the default rules with a dummy user-tag. These
+ * rules are always weekly tracked... */
nmp_rules_manager_track_default (priv->rules_manager,
AF_UNSPEC,
0,
nm_netns_parent_class /* static dummy user-tag */);
+
+ /* Also weakly track all existing rules. These were added before NetworkManager
+ * starts, so they are probably none of NetworkManager's business.
+ *
+ * However note that during service restart, devices may stay up and rules kept.
+ * That means, after restart such rules may have been added by a previous run
+ * of NetworkManager, we just don't know.
+ *
+ * For that reason, whenever we will touch such rules later one, we make them
+ * fully owned and no longer weekly tracked. See %NMP_RULES_MANAGER_EXTERN_WEAKLY_TRACKED_USER_TAG. */
nmp_rules_manager_track_from_platform (priv->rules_manager,
NULL,
AF_UNSPEC,
0,
- nm_netns_parent_class /* static dummy user-tag */);
+ NMP_RULES_MANAGER_EXTERN_WEAKLY_TRACKED_USER_TAG);
G_OBJECT_CLASS (nm_netns_parent_class)->constructed (object);
}
diff --git a/src/platform/nmp-rules-manager.c b/src/platform/nmp-rules-manager.c
index 970afcde5..53174e575 100644
--- a/src/platform/nmp-rules-manager.c
+++ b/src/platform/nmp-rules-manager.c
@@ -99,6 +99,17 @@ typedef enum {
CONFIG_STATE_NONE = 0,
CONFIG_STATE_ADDED_BY_US = 1,
CONFIG_STATE_REMOVED_BY_US = 2,
+
+ /* ConfigState encodes whether the rule was touched by us at all (CONFIG_STATE_NONE).
+ *
+ * Maybe we would only need to track whether we touched the rule at all. But we
+ * track it more in detail what we did: did we add it (CONFIG_STATE_ADDED_BY_US)
+ * or did we remove it (CONFIG_STATE_REMOVED_BY_US)?
+ * Finally, we need CONFIG_STATE_OWNED_BY_US, which means that we didn't actively
+ * add/remove it, but whenever we are about to undo the add/remove, we need to do it.
+ * In that sense, CONFIG_STATE_OWNED_BY_US is really just a flag that we unconditionally
+ * force the state next time when necessary. */
+ CONFIG_STATE_OWNED_BY_US = 3,
} ConfigState;
typedef struct {
@@ -111,8 +122,10 @@ typedef struct {
* This makes NMPRulesManager stateful (beyond the configuration that indicates
* which rules are tracked).
* After a restart, NetworkManager would no longer remember which rules were added
- * by us. That would need to be fixed by persisting the state and reloading it after
- * restart. */
+ * by us.
+ *
+ * That is partially fixed by NetworkManager taking over the rules that it
+ * actively configures (see %NMP_RULES_MANAGER_EXTERN_WEAKLY_TRACKED_USER_TAG). */
ConfigState config_state;
} RulesObjData;
@@ -121,6 +134,15 @@ typedef struct {
CList user_tag_lst_head;
} RulesUserTagData;
+/*****************************************************************************/
+
+static void _rules_data_untrack (NMPRulesManager *self,
+ RulesData *rules_data,
+ gboolean remove_user_tag_data,
+ gboolean make_owned_by_us);
+
+/*****************************************************************************/
+
static void
_rules_data_assert (const RulesData *rules_data, gboolean linked)
{
@@ -278,11 +300,31 @@ _rules_data_lookup (GHashTable *by_data,
return g_hash_table_lookup (by_data, &rules_data_needle);
}
+/**
+ * nmp_rules_manager_track:
+ * @self: the #NMPRulesManager instance
+ * @routing_rule: the #NMPlatformRoutingRule to track or untrack
+ * @track_priority: the priority for tracking the rule. Note that
+ * negative values indicate a forced absence of the rule. Priorities
+ * are compared with their absolute values (with higher absolute
+ * value being more important). For example, if you track the same
+ * rule twice, once with priority -5 and +10, then the rule is
+ * present (because the positive number is more important).
+ * The special value 0 indicates weakly-tracked rules.
+ * @user_tag: the tag associated with tracking this rule. The same tag
+ * must be used to untrack the rule later.
+ * @user_tag_untrack: if not %NULL, at the same time untrack this user-tag
+ * for the same rule. Note that this is different from a plain nmp_rules_manager_untrack(),
+ * because it enforces ownership of the now tracked rule. On the other hand,
+ * a plain nmp_rules_manager_untrack() merely forgets about the tracking.
+ * The purpose here is to set this to %NMP_RULES_MANAGER_EXTERN_WEAKLY_TRACKED_USER_TAG.
+ */
void
nmp_rules_manager_track (NMPRulesManager *self,
const NMPlatformRoutingRule *routing_rule,
gint32 track_priority,
- gconstpointer user_tag)
+ gconstpointer user_tag,
+ gconstpointer user_tag_untrack)
{
NMPObject obj_stack;
const NMPObject *p_obj_stack;
@@ -359,6 +401,17 @@ nmp_rules_manager_track (NMPRulesManager *self,
}
}
+ if (user_tag_untrack) {
+ if (user_tag != user_tag_untrack) {
+ RulesData *rules_data_untrack;
+
+ rules_data_untrack = _rules_data_lookup (self->by_data, p_obj_stack, user_tag_untrack);
+ if (rules_data_untrack)
+ _rules_data_untrack (self, rules_data_untrack, FALSE, TRUE);
+ } else
+ nm_assert_not_reached ();
+ }
+
_rules_data_assert (rules_data, TRUE);
if (changed) {
@@ -377,7 +430,8 @@ nmp_rules_manager_track (NMPRulesManager *self,
static void
_rules_data_untrack (NMPRulesManager *self,
RulesData *rules_data,
- gboolean remove_user_tag_data)
+ gboolean remove_user_tag_data,
+ gboolean make_owned_by_us)
{
RulesObjData *obj_data;
@@ -401,15 +455,22 @@ _rules_data_untrack (NMPRulesManager *self,
#endif
nm_assert (!c_list_is_empty (&rules_data->user_tag_lst));
- if ( remove_user_tag_data
- && c_list_length_is (&rules_data->user_tag_lst, 1))
- g_hash_table_remove (self->by_user_tag, &rules_data->user_tag);
obj_data = g_hash_table_lookup (self->by_obj, &rules_data->obj);
nm_assert (obj_data);
nm_assert (c_list_contains (&obj_data->obj_lst_head, &rules_data->obj_lst));
nm_assert (obj_data == g_hash_table_lookup (self->by_obj, &rules_data->obj));
+ if (make_owned_by_us) {
+ if (obj_data->config_state == CONFIG_STATE_NONE) {
+ /* we need to mark this entry that it requires a touch on the next
+ * sync. */
+ obj_data->config_state = CONFIG_STATE_OWNED_BY_US;
+ }
+ } else if ( remove_user_tag_data
+ && c_list_length_is (&rules_data->user_tag_lst, 1))
+ g_hash_table_remove (self->by_user_tag, &rules_data->user_tag);
+
/* if obj_data is marked to be "added_by_us" or "removed_by_us", we need to keep this entry
* around for the next sync -- so that we can undo what we did earlier. */
if ( obj_data->config_state == CONFIG_STATE_NONE
@@ -440,7 +501,7 @@ nmp_rules_manager_untrack (NMPRulesManager *self,
rules_data = _rules_data_lookup (self->by_data, p_obj_stack, user_tag);
if (rules_data)
- _rules_data_untrack (self, rules_data, TRUE);
+ _rules_data_untrack (self, rules_data, TRUE, FALSE);
}
void
@@ -486,7 +547,7 @@ nmp_rules_manager_untrack_all (NMPRulesManager *self,
c_list_for_each_entry_safe (rules_data, rules_data_safe, &user_tag_data->user_tag_lst_head, user_tag_lst) {
if ( all
|| rules_data->dirty)
- _rules_data_untrack (self, rules_data, FALSE);
+ _rules_data_untrack (self, rules_data, FALSE, FALSE);
}
if (c_list_is_empty (&user_tag_data->user_tag_lst_head))
g_hash_table_remove (self->by_user_tag, user_tag_data);
@@ -525,11 +586,17 @@ nmp_rules_manager_sync (NMPRulesManager *self,
rd_best = _rules_obj_get_best_data (obj_data);
if (rd_best) {
- if (rd_best->track_priority_present)
+ if (rd_best->track_priority_present) {
+ if (obj_data->config_state == CONFIG_STATE_OWNED_BY_US)
+ obj_data->config_state = CONFIG_STATE_ADDED_BY_US;
continue;
+ }
if (rd_best->track_priority_val == 0) {
- if (obj_data->config_state != CONFIG_STATE_ADDED_BY_US)
+ if (!NM_IN_SET (obj_data->config_state, CONFIG_STATE_ADDED_BY_US,
+ CONFIG_STATE_OWNED_BY_US)) {
+ obj_data->config_state = CONFIG_STATE_NONE;
continue;
+ }
obj_data->config_state = CONFIG_STATE_NONE;
}
}
@@ -563,11 +630,17 @@ nmp_rules_manager_sync (NMPRulesManager *self,
continue;
}
- if (!rd_best->track_priority_present)
+ if (!rd_best->track_priority_present) {
+ if (obj_data->config_state == CONFIG_STATE_OWNED_BY_US)
+ obj_data->config_state = CONFIG_STATE_REMOVED_BY_US;
continue;
+ }
if (rd_best->track_priority_val == 0) {
- if (obj_data->config_state != CONFIG_STATE_REMOVED_BY_US)
+ if (!NM_IN_SET (obj_data->config_state, CONFIG_STATE_REMOVED_BY_US,
+ CONFIG_STATE_OWNED_BY_US)) {
+ obj_data->config_state = CONFIG_STATE_NONE;
continue;
+ }
obj_data->config_state = CONFIG_STATE_NONE;
}
@@ -610,7 +683,7 @@ nmp_rules_manager_track_from_platform (NMPRulesManager *self,
&& rr->addr_family != addr_family)
continue;
- nmp_rules_manager_track (self, rr, tracking_priority, user_tag);
+ nmp_rules_manager_track (self, rr, tracking_priority, user_tag, NULL);
}
}
@@ -638,7 +711,8 @@ nmp_rules_manager_track_default (NMPRulesManager *self,
.protocol = RTPROT_KERNEL,
}),
track_priority,
- user_tag);
+ user_tag,
+ NULL);
nmp_rules_manager_track (self,
&((NMPlatformRoutingRule) {
.addr_family = AF_INET,
@@ -648,7 +722,8 @@ nmp_rules_manager_track_default (NMPRulesManager *self,
.protocol = RTPROT_KERNEL,
}),
track_priority,
- user_tag);
+ user_tag,
+ NULL);
nmp_rules_manager_track (self,
&((NMPlatformRoutingRule) {
.addr_family = AF_INET,
@@ -658,7 +733,8 @@ nmp_rules_manager_track_default (NMPRulesManager *self,
.protocol = RTPROT_KERNEL,
}),
track_priority,
- user_tag);
+ user_tag,
+ NULL);
}
if (NM_IN_SET (addr_family, AF_UNSPEC, AF_INET6)) {
nmp_rules_manager_track (self,
@@ -670,7 +746,8 @@ nmp_rules_manager_track_default (NMPRulesManager *self,
.protocol = RTPROT_KERNEL,
}),
track_priority,
- user_tag);
+ user_tag,
+ NULL);
nmp_rules_manager_track (self,
&((NMPlatformRoutingRule) {
.addr_family = AF_INET6,
@@ -680,7 +757,8 @@ nmp_rules_manager_track_default (NMPRulesManager *self,
.protocol = RTPROT_KERNEL,
}),
track_priority,
- user_tag);
+ user_tag,
+ NULL);
}
}
diff --git a/src/platform/nmp-rules-manager.h b/src/platform/nmp-rules-manager.h
index 310c7971f..645df5c28 100644
--- a/src/platform/nmp-rules-manager.h
+++ b/src/platform/nmp-rules-manager.h
@@ -22,6 +22,8 @@
/*****************************************************************************/
+#define NMP_RULES_MANAGER_EXTERN_WEAKLY_TRACKED_USER_TAG ((const void *) nmp_rules_manager_new)
+
typedef struct _NMPRulesManager NMPRulesManager;
NMPRulesManager *nmp_rules_manager_new (NMPlatform *platform);
@@ -35,7 +37,8 @@ NM_AUTO_DEFINE_FCN0 (NMPRulesManager *, _nmp_rules_manager_unref, nmp_rules_mana
void nmp_rules_manager_track (NMPRulesManager *self,
const NMPlatformRoutingRule *routing_rule,
gint32 track_priority,
- gconstpointer user_tag);
+ gconstpointer user_tag,
+ gconstpointer user_tag_untrack);
void nmp_rules_manager_track_default (NMPRulesManager *self,
int addr_family,
diff --git a/src/platform/tests/test-route.c b/src/platform/tests/test-route.c
index 0d7fdcf33..44bfbc583 100644
--- a/src/platform/tests/test-route.c
+++ b/src/platform/tests/test-route.c
@@ -1534,14 +1534,16 @@ again:
nmp_rules_manager_track (rules_manager,
NMP_OBJECT_CAST_ROUTING_RULE (objs_sync->pdata[i]),
1,
- USER_TAG_1);
+ USER_TAG_1,
+ NULL);
if (nmtst_get_rand_bool ()) {
/* this has no effect, because a negative priority (of same absolute value)
* has lower priority than the positive priority above. */
nmp_rules_manager_track (rules_manager,
NMP_OBJECT_CAST_ROUTING_RULE (objs_sync->pdata[i]),
-1,
- USER_TAG_2);
+ USER_TAG_2,
+ NULL);
}
if (nmtst_get_rand_uint32 () % objs_sync->len == 0) {
nmp_rules_manager_sync (rules_manager, FALSE);
@@ -1566,13 +1568,15 @@ again:
nmp_rules_manager_track (rules_manager,
NMP_OBJECT_CAST_ROUTING_RULE (objs_sync->pdata[i]),
-1,
- USER_TAG_1);
+ USER_TAG_1,
+ NULL);
break;
case 2:
nmp_rules_manager_track (rules_manager,
NMP_OBJECT_CAST_ROUTING_RULE (objs_sync->pdata[i]),
-2,
- USER_TAG_2);
+ USER_TAG_2,
+ NULL);
break;
}
if (nmtst_get_rand_uint32 () % objs_sync->len == 0) {