fib_rules: Added NLM_F_EXCL support to fib_nl_newrule
Subsystems (3)
PATCH v3 1/1 fib_rules: Added NLM_F_EXCL support to fib_nl_newrule
When adding rule with NLM_F_EXCL flag then check if the same rule exist. If yes then exit with -EEXIST.
This is already implemented in iproute2:
if (cmd == RTM_NEWRULE) {
req.n.nlmsg_flags |= NLM_F_CREATE|NLM_F_EXCL;
req.r.rtm_type = RTN_UNICAST;
}Tested ipv4 and ipv6 with net-next linux on qemu x86
expected behavior after patch:
localhost ~ # ip rule
0: from all lookup local
32766: from all lookup main
32767: from all lookup default
localhost ~ # ip rule add from 10.46.177.97 lookup 104 pref 1005 localhost ~ # ip rule add from 10.46.177.97 lookup 104 pref 1005 RTNETLINK answers: File exists
localhost ~ # ip rule
0: from all lookup local
1005: from 10.46.177.97 lookup 104
32766: from all lookup main
32767: from all lookup default
There was already topic regarding this but I don't see any changes merged and problem still occurs.
https://lkml.kernel.org/r/1135778809.5944.7.camel+%28%29+localhost+%21+localdomain
---
Changes in v2: section moved to new place where new rule is already built Changes in v3: compare moved to helper, added fr_net compare
net/core/fib_rules.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+)
net/core/fib_rules.c +46 -0
@@ -269,6 +269,46 @@ errout:return err; } +static int rule_exists (struct fib_rules_ops *ops,struct fib_rule_hdr *frh, +struct nlattr **tb,struct fib_rule *rule) +{ +struct fib_rule *r; + +list_for_each_entry (r, &ops->rules_list, list) { +if (r->action != rule->action) +continue ; + +if (r->table != rule->table) +continue ; + +if (r->pref != rule->pref) +continue ; + +if (memcmp (r->iifname, rule->iifname,IFNAMSIZ )) +continue ; + +if (memcmp (r->oifname, rule->oifname,IFNAMSIZ )) +continue ; + +if (r->mark != rule->mark) +continue ; + +if (r->mark_mask != rule->mark_mask) +continue ; + +if (r->tun_id != rule->tun_id) +continue ; + +if (r->fr_net != rule->fr_net) +continue ; + +if (!ops->compare (r, frh, tb)) +continue ; +return 1 ; + } +return 0 ; +} +int fib_nl_newrule (struct sk_buff *skb,struct nlmsghdr *nlh) {struct net *net =sock_net (skb->sk);
@@ -386,6 +426,12 @@ int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh)if (rule->l3mdev && rule->table) goto errout_free; +if ((nlh->nlmsg_flags &NLM_F_EXCL ) && +rule_exists (ops, frh, tb, rule)) { + err = -EEXIST ; + goto errout_free; + } + err = ops->configure (rule, skb, frh, tb);if (err <0 ) goto errout_free;
Signature · 1 line
2.6.4
Quoted 33 lines · Mateusz Bajorski
net/core/fib_rules.c +25
-0@@ -269,6 +269,46 @@ errout:return err; } +static int rule_exists (struct fib_rules_ops *ops,struct fib_rule_hdr *frh, +struct nlattr **tb,struct fib_rule *rule) +{ +struct fib_rule *r; + +list_for_each_entry (r, &ops->rules_list, list) { +if (r->action != rule->action) +continue ; + +if (r->table != rule->table) +continue ; + +if (r->pref != rule->pref) +continue ; + +if (memcmp (r->iifname, rule->iifname,IFNAMSIZ )) +continue ; + +if (memcmp (r->oifname, rule->oifname,IFNAMSIZ )) +continue ; + +if (r->mark != rule->mark) +continue ; + +if (r->mark_mask != rule->mark_mask)
net/core/fib_rules.c errout: · line 306
Quoted 10 lines
net/core/fib_rules.c +10
-0+continue ; + +if (r->tun_id != rule->tun_id) +continue ; + +if (r->fr_net != rule->fr_net) +continue ; + +if (!ops->compare (r, frh, tb)) +continue ;
l3mdev attribute snuck in a couple of weeks ago. You need to compare r->l3mdev != rule->l3mdev