Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit cff478b9 authored by Nicolas Dichtel's avatar Nicolas Dichtel Committed by David S. Miller
Browse files

netns: add support of NETNSA_TARGET_NSID 



Like it was done for link and address, add the ability to perform get/dump
in another netns by specifying a target nsid attribute.

Signed-off-by: default avatarNicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: default avatarDavid Ahern <dsahern@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a0732ad1

include/uapi/linux/net_namespace.h

+1 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ enum { 
	NETNSA_NSID,

	NETNSA_PID,

	NETNSA_FD,

	NETNSA_TARGET_NSID,

	__NETNSA_MAX,

};

net/core/net_namespace.c

+75 −11
Original line number Diff line number Diff line
@@ -669,6 +669,7 @@ static const struct nla_policy rtnl_net_policy[NETNSA_MAX + 1] = { 
	[NETNSA_NSID]		= { .type = NLA_S32 },

	[NETNSA_PID]		= { .type = NLA_U32 },

	[NETNSA_FD]		= { .type = NLA_U32 },

	[NETNSA_TARGET_NSID]	= { .type = NLA_S32 },

};



static int rtnl_net_newid(struct sk_buff *skb, struct nlmsghdr *nlh,
@@ -780,9 +781,10 @@ static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh, 
		.seq = nlh->nlmsg_seq,

		.cmd = RTM_NEWNSID,

	};

	struct net *peer, *target = net;

	bool put_target = false;

	struct nlattr *nla;

	struct sk_buff *msg;

	struct net *peer;

	int err;



	err = nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, NETNSA_MAX,
@@ -806,13 +808,27 @@ static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh, 
		return PTR_ERR(peer);

	}



	if (tb[NETNSA_TARGET_NSID]) {

		int id = nla_get_s32(tb[NETNSA_TARGET_NSID]);



		target = rtnl_get_net_ns_capable(NETLINK_CB(skb).sk, id);

		if (IS_ERR(target)) {

			NL_SET_BAD_ATTR(extack, tb[NETNSA_TARGET_NSID]);

			NL_SET_ERR_MSG(extack,

				       "Target netns reference is invalid");

			err = PTR_ERR(target);

			goto out;

		}

		put_target = true;

	}



	msg = nlmsg_new(rtnl_net_get_size(), GFP_KERNEL);

	if (!msg) {

		err = -ENOMEM;

		goto out;

	}



	fillargs.nsid = peernet2id(net, peer);

	fillargs.nsid = peernet2id(target, peer);

	err = rtnl_net_fill(msg, &fillargs);

	if (err < 0)

		goto err_out;
@@ -823,15 +839,19 @@ static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh, 
err_out:

	nlmsg_free(msg);

out:

	if (put_target)

		put_net(target);

	put_net(peer);

	return err;

}



struct rtnl_net_dump_cb {

	struct net *tgt_net;

	struct sk_buff *skb;

	struct net_fill_args fillargs;

	int idx;

	int s_idx;

	bool put_tgt_net;

};



static int rtnl_net_dumpid_one(int id, void *peer, void *data)
@@ -852,10 +872,50 @@ static int rtnl_net_dumpid_one(int id, void *peer, void *data) 
	return 0;

}



static int rtnl_valid_dump_net_req(const struct nlmsghdr *nlh, struct sock *sk,

				   struct rtnl_net_dump_cb *net_cb,

				   struct netlink_callback *cb)

{

	struct netlink_ext_ack *extack = cb->extack;

	struct nlattr *tb[NETNSA_MAX + 1];

	int err, i;



	err = nlmsg_parse_strict(nlh, sizeof(struct rtgenmsg), tb, NETNSA_MAX,

				 rtnl_net_policy, extack);

	if (err < 0)

		return err;



	for (i = 0; i <= NETNSA_MAX; i++) {

		if (!tb[i])

			continue;



		if (i == NETNSA_TARGET_NSID) {

			struct net *net;



			net = rtnl_get_net_ns_capable(sk, nla_get_s32(tb[i]));

			if (IS_ERR(net)) {

				NL_SET_BAD_ATTR(extack, tb[i]);

				NL_SET_ERR_MSG(extack,

					       "Invalid target network namespace id");

				return PTR_ERR(net);

			}

			net_cb->tgt_net = net;

			net_cb->put_tgt_net = true;

		} else {

			NL_SET_BAD_ATTR(extack, tb[i]);

			NL_SET_ERR_MSG(extack,

				       "Unsupported attribute in dump request");

			return -EINVAL;

		}

	}



	return 0;

}



static int rtnl_net_dumpid(struct sk_buff *skb, struct netlink_callback *cb)

{

	struct net *net = sock_net(skb->sk);

	struct rtnl_net_dump_cb net_cb = {

		.tgt_net = sock_net(skb->sk),

		.skb = skb,

		.fillargs = {

			.portid = NETLINK_CB(cb->skb).portid,
@@ -866,19 +926,23 @@ static int rtnl_net_dumpid(struct sk_buff *skb, struct netlink_callback *cb) 
		.idx = 0,

		.s_idx = cb->args[0],

	};

	int err = 0;



	if (cb->strict_check &&

	    nlmsg_attrlen(cb->nlh, sizeof(struct rtgenmsg))) {

			NL_SET_ERR_MSG(cb->extack, "Unknown data in network namespace id dump request");

			return -EINVAL;

	if (cb->strict_check) {

		err = rtnl_valid_dump_net_req(cb->nlh, skb->sk, &net_cb, cb);

		if (err < 0)

			goto end;

	}



	spin_lock_bh(&net->nsid_lock);

	idr_for_each(&net->netns_ids, rtnl_net_dumpid_one, &net_cb);

	spin_unlock_bh(&net->nsid_lock);

	spin_lock_bh(&net_cb.tgt_net->nsid_lock);

	idr_for_each(&net_cb.tgt_net->netns_ids, rtnl_net_dumpid_one, &net_cb);

	spin_unlock_bh(&net_cb.tgt_net->nsid_lock);



	cb->args[0] = net_cb.idx;

	return skb->len;

end:

	if (net_cb.put_tgt_net)

		put_net(net_cb.tgt_net);

	return err < 0 ? err : skb->len;

}



static void rtnl_net_notifyid(struct net *net, int cmd, int id)