Commit 0bccf8ed authored by Petr Machata's avatar Petr Machata Committed by Jakub Kicinski
Browse files

nexthop: Extract a helper for validation of get/del RTNL requests 



Validation of messages for get / del of a next hop is the same as will be
validation of messages for get of a resilient next hop group bucket. The
difference is that policy for resilient next hop group buckets is a
superset of that used for next-hop get.

It is therefore possible to reuse the code that validates the nhmsg fields,
extracts the next-hop ID, and validates that. To that end, extract from
nh_valid_get_del_req() a helper __nh_valid_get_del_req() that does just
that.

Make the nlh argument const so that the function can be called from the
dump context, which only has a const nlh. Propagate the constness to
nh_valid_get_del_req().

Signed-off-by: default avatarPetr Machata <petrm@nvidia.com>
Reviewed-by: default avatarIdo Schimmel <idosch@nvidia.com>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent e948217d

net/ipv4/nexthop.c

+25 −18
Original line number Diff line number Diff line
@@ -1872,37 +1872,44 @@ static int rtm_new_nexthop(struct sk_buff *skb, struct nlmsghdr *nlh, 
	return err;

}



static int nh_valid_get_del_req(struct nlmsghdr *nlh, u32 *id,

static int __nh_valid_get_del_req(const struct nlmsghdr *nlh,

				  struct nlattr **tb, u32 *id,

				  struct netlink_ext_ack *extack)

{

	struct nhmsg *nhm = nlmsg_data(nlh);

	struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_get)];

	int err;



	err = nlmsg_parse(nlh, sizeof(*nhm), tb,

			  ARRAY_SIZE(rtm_nh_policy_get) - 1,

			  rtm_nh_policy_get, extack);

	if (err < 0)

		return err;



	err = -EINVAL;

	if (nhm->nh_protocol || nhm->resvd || nhm->nh_scope || nhm->nh_flags) {

		NL_SET_ERR_MSG(extack, "Invalid values in header");

		goto out;

		return -EINVAL;

	}



	if (!tb[NHA_ID]) {

		NL_SET_ERR_MSG(extack, "Nexthop id is missing");

		goto out;

		return -EINVAL;

	}



	*id = nla_get_u32(tb[NHA_ID]);

	if (!(*id))

	if (!(*id)) {

		NL_SET_ERR_MSG(extack, "Invalid nexthop id");

	else

		err = 0;

out:

		return -EINVAL;

	}



	return 0;

}



static int nh_valid_get_del_req(const struct nlmsghdr *nlh, u32 *id,

				struct netlink_ext_ack *extack)

{

	struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_get)];

	int err;



	err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb,

			  ARRAY_SIZE(rtm_nh_policy_get) - 1,

			  rtm_nh_policy_get, extack);

	if (err < 0)

		return err;



	return __nh_valid_get_del_req(nlh, tb, id, extack);

}



/* rtnl */