[NETFILTER]: nfnetlink: support attribute policies
Add support for automatic checking of per-callback attribute policies.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index e212102..cb41990 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -111,35 +111,6 @@
return &ss->cb[cb_id];
}
-/**
- * nfnetlink_check_attributes - check and parse nfnetlink attributes
- *
- * subsys: nfnl subsystem for which this message is to be parsed
- * nlmsghdr: netlink message to be checked/parsed
- * cda: array of pointers, needs to be at least subsys->attr_count+1 big
- *
- */
-static int
-nfnetlink_check_attributes(const struct nfnetlink_subsystem *subsys,
- struct nlmsghdr *nlh, struct nlattr *cda[])
-{
- int min_len = NLMSG_SPACE(sizeof(struct nfgenmsg));
- u_int8_t cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type);
- u_int16_t attr_count = subsys->cb[cb_id].attr_count;
-
- /* check attribute lengths. */
- if (likely(nlh->nlmsg_len > min_len)) {
- struct nlattr *attr = (void *)nlh + NLMSG_ALIGN(min_len);
- int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
- nla_parse(cda, attr_count, attr, attrlen, NULL);
- }
-
- /* implicit: if nlmsg_len == min_len, we return 0, and an empty
- * (zeroed) cda[] array. The message is valid, but empty. */
-
- return 0;
-}
-
int nfnetlink_has_listeners(unsigned int group)
{
return netlink_has_listeners(nfnl, group);
@@ -192,15 +163,22 @@
return -EINVAL;
{
- u_int16_t attr_count =
- ss->cb[NFNL_MSG_TYPE(nlh->nlmsg_type)].attr_count;
+ int min_len = NLMSG_SPACE(sizeof(struct nfgenmsg));
+ u_int8_t cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type);
+ u_int16_t attr_count = ss->cb[cb_id].attr_count;
struct nlattr *cda[attr_count+1];
- memset(cda, 0, sizeof(struct nlattr *) * attr_count);
+ if (likely(nlh->nlmsg_len >= min_len)) {
+ struct nlattr *attr = (void *)nlh + NLMSG_ALIGN(min_len);
+ int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
- err = nfnetlink_check_attributes(ss, nlh, cda);
- if (err < 0)
- return err;
+ err = nla_parse(cda, attr_count, attr, attrlen,
+ ss->cb[cb_id].policy);
+ if (err < 0)
+ return err;
+ } else
+ return -EINVAL;
+
return nc->call(nfnl, skb, nlh, cda);
}
}
