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Diffstat (limited to 'net/core/fib_rules.c')
-rw-r--r--net/core/fib_rules.c161
1 files changed, 143 insertions, 18 deletions
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index 7174ced75efc..8c5474e16683 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -44,6 +44,12 @@ static void rules_ops_put(struct fib_rules_ops *ops)
module_put(ops->owner);
}
+static void flush_route_cache(struct fib_rules_ops *ops)
+{
+ if (ops->flush_cache)
+ ops->flush_cache();
+}
+
int fib_rules_register(struct fib_rules_ops *ops)
{
int err = -EEXIST;
@@ -132,10 +138,25 @@ int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
rcu_read_lock();
list_for_each_entry_rcu(rule, ops->rules_list, list) {
+jumped:
if (!fib_rule_match(rule, ops, fl, flags))
continue;
- err = ops->action(rule, fl, flags, arg);
+ if (rule->action == FR_ACT_GOTO) {
+ struct fib_rule *target;
+
+ target = rcu_dereference(rule->ctarget);
+ if (target == NULL) {
+ continue;
+ } else {
+ rule = target;
+ goto jumped;
+ }
+ } else if (rule->action == FR_ACT_NOP)
+ continue;
+ else
+ err = ops->action(rule, fl, flags, arg);
+
if (err != -EAGAIN) {
fib_rule_get(rule);
arg->rule = rule;
@@ -174,13 +195,13 @@ errout:
return err;
}
-int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
+static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
{
struct fib_rule_hdr *frh = nlmsg_data(nlh);
struct fib_rules_ops *ops = NULL;
struct fib_rule *rule, *r, *last = NULL;
struct nlattr *tb[FRA_MAX+1];
- int err = -EINVAL;
+ int err = -EINVAL, unresolved = 0;
if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
goto errout;
@@ -237,6 +258,28 @@ int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
if (!rule->pref && ops->default_pref)
rule->pref = ops->default_pref();
+ err = -EINVAL;
+ if (tb[FRA_GOTO]) {
+ if (rule->action != FR_ACT_GOTO)
+ goto errout_free;
+
+ rule->target = nla_get_u32(tb[FRA_GOTO]);
+ /* Backward jumps are prohibited to avoid endless loops */
+ if (rule->target <= rule->pref)
+ goto errout_free;
+
+ list_for_each_entry(r, ops->rules_list, list) {
+ if (r->pref == rule->target) {
+ rule->ctarget = r;
+ break;
+ }
+ }
+
+ if (rule->ctarget == NULL)
+ unresolved = 1;
+ } else if (rule->action == FR_ACT_GOTO)
+ goto errout_free;
+
err = ops->configure(rule, skb, nlh, frh, tb);
if (err < 0)
goto errout_free;
@@ -249,12 +292,35 @@ int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
fib_rule_get(rule);
+ if (ops->unresolved_rules) {
+ /*
+ * There are unresolved goto rules in the list, check if
+ * any of them are pointing to this new rule.
+ */
+ list_for_each_entry(r, ops->rules_list, list) {
+ if (r->action == FR_ACT_GOTO &&
+ r->target == rule->pref) {
+ BUG_ON(r->ctarget != NULL);
+ rcu_assign_pointer(r->ctarget, rule);
+ if (--ops->unresolved_rules == 0)
+ break;
+ }
+ }
+ }
+
+ if (rule->action == FR_ACT_GOTO)
+ ops->nr_goto_rules++;
+
+ if (unresolved)
+ ops->unresolved_rules++;
+
if (last)
list_add_rcu(&rule->list, &last->list);
else
list_add_rcu(&rule->list, ops->rules_list);
notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).pid);
+ flush_route_cache(ops);
rules_ops_put(ops);
return 0;
@@ -265,11 +331,11 @@ errout:
return err;
}
-int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
+static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
{
struct fib_rule_hdr *frh = nlmsg_data(nlh);
struct fib_rules_ops *ops = NULL;
- struct fib_rule *rule;
+ struct fib_rule *rule, *tmp;
struct nlattr *tb[FRA_MAX+1];
int err = -EINVAL;
@@ -322,10 +388,30 @@ int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
}
list_del_rcu(&rule->list);
+
+ if (rule->action == FR_ACT_GOTO)
+ ops->nr_goto_rules--;
+
+ /*
+ * Check if this rule is a target to any of them. If so,
+ * disable them. As this operation is eventually very
+ * expensive, it is only performed if goto rules have
+ * actually been added.
+ */
+ if (ops->nr_goto_rules > 0) {
+ list_for_each_entry(tmp, ops->rules_list, list) {
+ if (tmp->ctarget == rule) {
+ rcu_assign_pointer(tmp->ctarget, NULL);
+ ops->unresolved_rules++;
+ }
+ }
+ }
+
synchronize_rcu();
notify_rule_change(RTM_DELRULE, rule, ops, nlh,
NETLINK_CB(skb).pid);
fib_rule_put(rule);
+ flush_route_cache(ops);
rules_ops_put(ops);
return 0;
}
@@ -371,9 +457,16 @@ static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
frh->action = rule->action;
frh->flags = rule->flags;
- if (rule->ifname[0])
+ if (rule->action == FR_ACT_GOTO && rule->ctarget == NULL)
+ frh->flags |= FIB_RULE_UNRESOLVED;
+
+ if (rule->ifname[0]) {
NLA_PUT_STRING(skb, FRA_IFNAME, rule->ifname);
+ if (rule->ifindex == -1)
+ frh->flags |= FIB_RULE_DEV_DETACHED;
+ }
+
if (rule->pref)
NLA_PUT_U32(skb, FRA_PRIORITY, rule->pref);
@@ -383,6 +476,9 @@ static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
if (rule->mark_mask || rule->mark)
NLA_PUT_U32(skb, FRA_FWMASK, rule->mark_mask);
+ if (rule->target)
+ NLA_PUT_U32(skb, FRA_GOTO, rule->target);
+
if (ops->fill(rule, skb, nlh, frh) < 0)
goto nla_put_failure;
@@ -393,19 +489,14 @@ nla_put_failure:
return -EMSGSIZE;
}
-int fib_rules_dump(struct sk_buff *skb, struct netlink_callback *cb, int family)
+static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
+ struct fib_rules_ops *ops)
{
int idx = 0;
struct fib_rule *rule;
- struct fib_rules_ops *ops;
-
- ops = lookup_rules_ops(family);
- if (ops == NULL)
- return -EAFNOSUPPORT;
- rcu_read_lock();
- list_for_each_entry_rcu(rule, ops->rules_list, list) {
- if (idx < cb->args[0])
+ list_for_each_entry(rule, ops->rules_list, list) {
+ if (idx < cb->args[1])
goto skip;
if (fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).pid,
@@ -415,14 +506,44 @@ int fib_rules_dump(struct sk_buff *skb, struct netlink_callback *cb, int family)
skip:
idx++;
}
- rcu_read_unlock();
- cb->args[0] = idx;
+ cb->args[1] = idx;
rules_ops_put(ops);
return skb->len;
}
-EXPORT_SYMBOL_GPL(fib_rules_dump);
+static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct fib_rules_ops *ops;
+ int idx = 0, family;
+
+ family = rtnl_msg_family(cb->nlh);
+ if (family != AF_UNSPEC) {
+ /* Protocol specific dump request */
+ ops = lookup_rules_ops(family);
+ if (ops == NULL)
+ return -EAFNOSUPPORT;
+
+ return dump_rules(skb, cb, ops);
+ }
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ops, &rules_ops, list) {
+ if (idx < cb->args[0] || !try_module_get(ops->owner))
+ goto skip;
+
+ if (dump_rules(skb, cb, ops) < 0)
+ break;
+
+ cb->args[1] = 0;
+ skip:
+ idx++;
+ }
+ rcu_read_unlock();
+ cb->args[0] = idx;
+
+ return skb->len;
+}
static void notify_rule_change(int event, struct fib_rule *rule,
struct fib_rules_ops *ops, struct nlmsghdr *nlh,
@@ -501,6 +622,10 @@ static struct notifier_block fib_rules_notifier = {
static int __init fib_rules_init(void)
{
+ rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL);
+ rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL);
+ rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule);
+
return register_netdevice_notifier(&fib_rules_notifier);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 23:39:53 +0000