fib_rules: fix suppressor names and default values

This change brings the suppressor attribute names into line; it also changes
the data types to provide a more consistent interface.

While -1 indicates that the suppressor is not enabled, values >= 0 for
suppress_prefixlen or suppress_ifgroup  reject routing decisions violating the
constraint.

This changes the previously presented behaviour of suppress_prefixlen, where a
prefix length _less_ than the attribute value was rejected. After this change,
a prefix length less than *or* equal to the value is considered a violation of
the rule constraint.

It also changes the default values for default and newly added rules (disabling
any suppression for those).

Signed-off-by: Stefan Tomanek <stefan.tomanek@wertarbyte.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 4 deletions

diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index 5040a61bf28a..2e654138433c 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -33,6 +33,9 @@ int fib_default_rule_add(struct fib_rules_ops *ops,
         r->flags = flags;
         r->fr_net = hold_net(ops->fro_net);
 
+        r->suppress_prefixlen = -1;
+        r->suppress_ifgroup = -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);
@@ -340,11 +343,15 @@ static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh)
         rule->action = frh->action;
         rule->flags = frh->flags;
         rule->table = frh_get_table(frh, tb);
-        if (tb[FRA_TABLE_PREFIXLEN_MIN])
-                rule->table_prefixlen_min = nla_get_u8(tb[FRA_TABLE_PREFIXLEN_MIN]);
+        if (tb[FRA_SUPPRESS_PREFIXLEN])
+                rule->suppress_prefixlen = nla_get_u32(tb[FRA_SUPPRESS_PREFIXLEN]);
+        else
+                rule->suppress_prefixlen = -1;
 
         if (tb[FRA_SUPPRESS_IFGROUP])
                 rule->suppress_ifgroup = nla_get_u32(tb[FRA_SUPPRESS_IFGROUP]);
+        else
+                rule->suppress_ifgroup = -1;
 
         if (!tb[FRA_PRIORITY] && ops->default_pref)
                 rule->pref = ops->default_pref(ops);
@@ -531,7 +538,7 @@ static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
                          + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
                          + nla_total_size(4) /* FRA_PRIORITY */
                          + nla_total_size(4) /* FRA_TABLE */
-                         + nla_total_size(1) /* FRA_TABLE_PREFIXLEN_MIN */
+                         + nla_total_size(4) /* FRA_SUPPRESS_PREFIXLEN */
                          + nla_total_size(4) /* FRA_SUPPRESS_IFGROUP */
                          + nla_total_size(4) /* FRA_FWMARK */
                          + nla_total_size(4); /* FRA_FWMASK */
@@ -558,7 +565,7 @@ static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
         frh->table = rule->table;
         if (nla_put_u32(skb, FRA_TABLE, rule->table))
                 goto nla_put_failure;
-        if (nla_put_u8(skb, FRA_TABLE_PREFIXLEN_MIN, rule->table_prefixlen_min))
+        if (nla_put_u32(skb, FRA_SUPPRESS_PREFIXLEN, rule->suppress_prefixlen))
                 goto nla_put_failure;
         frh->res1 = 0;
         frh->res2 = 0;