When a user wants to assign a routing table to a group of incoming
interfaces, the current solutions are:
- one IP rule for each interface (scalability problems)
- use of fwmark and devgroup matcher (don't work with internal route
lookups, used for example by RPF)
- use of VRF devices (more complex)
Each interface can be assigned to a numeric group using IFLA_GROUP. This
commit enables a user to reference such a group into an IP rule. Here is
an example of output of iproute2:
$ ip rule show
0: from all lookup local
32764: from all iifgroup 2 lookup 2
32765: from all iifgroup 1 lookup 1
32766: from all lookup main
32767: from all lookup default
Signed-off-by: Vincent Bernat <[email protected]>
---
include/net/fib_rules.h | 6 ++++-
include/uapi/linux/fib_rules.h | 2 ++
net/core/fib_rules.c | 57 +++++++++++++++++++++++++++++++++++++++++-
3 files changed, 63 insertions(+), 2 deletions(-)
diff --git a/include/net/fib_rules.h b/include/net/fib_rules.h
index 456e4a6006ab..a96b186ccd02 100644
--- a/include/net/fib_rules.h
+++ b/include/net/fib_rules.h
@@ -28,6 +28,8 @@ struct fib_rule {
u32 pref;
int suppress_ifgroup;
int suppress_prefixlen;
+ int iifgroup;
+ int oifgroup;
char iifname[IFNAMSIZ];
char oifname[IFNAMSIZ];
struct rcu_head rcu;
@@ -92,7 +94,9 @@ struct fib_rules_ops {
[FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, \
[FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, \
[FRA_GOTO] = { .type = NLA_U32 }, \
- [FRA_L3MDEV] = { .type = NLA_U8 }
+ [FRA_L3MDEV] = { .type = NLA_U8 }, \
+ [FRA_IIFGROUP] = { .type = NLA_U32 }, \
+ [FRA_OIFGROUP] = { .type = NLA_U32 }
static inline void fib_rule_get(struct fib_rule *rule)
{
diff --git a/include/uapi/linux/fib_rules.h b/include/uapi/linux/fib_rules.h
index 14404b3ebb89..0bf5a5e94d9a 100644
--- a/include/uapi/linux/fib_rules.h
+++ b/include/uapi/linux/fib_rules.h
@@ -51,6 +51,8 @@ enum {
FRA_OIFNAME,
FRA_PAD,
FRA_L3MDEV, /* iif or oif is l3mdev goto its table */
+ FRA_IIFGROUP, /* interface group */
+ FRA_OIFGROUP,
__FRA_MAX
};
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index be4629c344a6..f8ed6ba85c72 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -37,6 +37,9 @@ int fib_default_rule_add(struct fib_rules_ops *ops,
r->suppress_prefixlen = -1;
r->suppress_ifgroup = -1;
+ r->iifgroup = -1;
+ r->oifgroup = -1;
+
/* The lock is not required here, the list in unreacheable
* at the moment this function is called */
list_add_tail(&r->list, &ops->rules_list);
@@ -193,6 +196,30 @@ static int fib_rule_match(struct fib_rule *rule, struct
fib_rules_ops *ops,
if (rule->l3mdev && !l3mdev_fib_rule_match(rule->fr_net, fl, arg))
goto out;
+ if (rule->iifgroup != -1) {
+ struct net_device *dev;
+
+ rcu_read_lock();
+ dev = dev_get_by_index_rcu(rule->fr_net, fl->flowi_iif);
+ if (!dev || dev->group != rule->iifgroup) {
+ rcu_read_unlock();
+ goto out;
+ }
+ rcu_read_unlock();
+ }
+
+ if (rule->oifgroup != -1) {
+ struct net_device *dev;
+
+ rcu_read_lock();
+ dev = dev_get_by_index_rcu(rule->fr_net, fl->flowi_oif);
+ if (!dev || dev->group != rule->oifgroup) {
+ rcu_read_unlock();
+ goto out;
+ }
+ rcu_read_unlock();
+ }
+
ret = ops->match(rule, fl, flags);
out:
return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
@@ -305,6 +332,12 @@ static int rule_exists(struct fib_rules_ops *ops, struct
fib_rule_hdr *frh,
if (r->l3mdev != rule->l3mdev)
continue;
+ if (r->iifgroup != rule->iifgroup)
+ continue;
+
+ if (r->oifgroup != rule->oifgroup)
+ continue;
+
if (!ops->compare(r, frh, tb))
continue;
return 1;
@@ -391,6 +424,16 @@ int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr
*nlh)
goto errout_free;
}
+ if (tb[FRA_IIFGROUP])
+ rule->iifgroup = nla_get_u32(tb[FRA_IIFGROUP]);
+ else
+ rule->iifgroup = -1;
+
+ if (tb[FRA_OIFGROUP])
+ rule->oifgroup = nla_get_u32(tb[FRA_OIFGROUP]);
+ else
+ rule->oifgroup = -1;
+
rule->action = frh->action;
rule->flags = frh->flags;
rule->table = frh_get_table(frh, tb);
@@ -552,6 +595,14 @@ int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr
*nlh)
(rule->l3mdev != nla_get_u8(tb[FRA_L3MDEV])))
continue;
+ if (tb[FRA_IIFGROUP] &&
+ (rule->iifgroup != nla_get_u32(tb[FRA_IIFGROUP])))
+ continue;
+
+ if (tb[FRA_OIFGROUP] &&
+ (rule->oifgroup != nla_get_u32(tb[FRA_OIFGROUP])))
+ continue;
+
if (!ops->compare(rule, frh, tb))
continue;
@@ -679,7 +730,11 @@ static int fib_nl_fill_rule(struct sk_buff *skb, struct
fib_rule *rule,
(rule->tun_id &&
nla_put_be64(skb, FRA_TUN_ID, rule->tun_id, FRA_PAD)) ||
(rule->l3mdev &&
- nla_put_u8(skb, FRA_L3MDEV, rule->l3mdev)))
+ nla_put_u8(skb, FRA_L3MDEV, rule->l3mdev)) ||
+ ((rule->iifgroup != -1) &&
+ nla_put_u32(skb, FRA_IIFGROUP, rule->iifgroup)) ||
+ ((rule->oifgroup != -1) &&
+ nla_put_u32(skb, FRA_OIFGROUP, rule->oifgroup)))
goto nla_put_failure;
if (rule->suppress_ifgroup != -1) {
--
2.9.3
