| // SPDX-License-Identifier: GPL-2.0-or-later | 
 | /* | 
 |  * udp_diag.c	Module for monitoring UDP transport protocols sockets. | 
 |  * | 
 |  * Authors:	Pavel Emelyanov, <xemul@parallels.com> | 
 |  */ | 
 |  | 
 |  | 
 | #include <linux/module.h> | 
 | #include <linux/inet_diag.h> | 
 | #include <linux/udp.h> | 
 | #include <net/udp.h> | 
 | #include <net/udplite.h> | 
 | #include <linux/sock_diag.h> | 
 |  | 
 | static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, | 
 | 			struct netlink_callback *cb, | 
 | 			const struct inet_diag_req_v2 *req, | 
 | 			struct nlattr *bc, bool net_admin) | 
 | { | 
 | 	if (!inet_diag_bc_sk(bc, sk)) | 
 | 		return 0; | 
 |  | 
 | 	return inet_sk_diag_fill(sk, NULL, skb, cb, req, NLM_F_MULTI, | 
 | 				 net_admin); | 
 | } | 
 |  | 
 | static int udp_dump_one(struct udp_table *tbl, | 
 | 			struct netlink_callback *cb, | 
 | 			const struct inet_diag_req_v2 *req) | 
 | { | 
 | 	struct sk_buff *in_skb = cb->skb; | 
 | 	int err = -EINVAL; | 
 | 	struct sock *sk = NULL; | 
 | 	struct sk_buff *rep; | 
 | 	struct net *net = sock_net(in_skb->sk); | 
 |  | 
 | 	rcu_read_lock(); | 
 | 	if (req->sdiag_family == AF_INET) | 
 | 		/* src and dst are swapped for historical reasons */ | 
 | 		sk = __udp4_lib_lookup(net, | 
 | 				req->id.idiag_src[0], req->id.idiag_sport, | 
 | 				req->id.idiag_dst[0], req->id.idiag_dport, | 
 | 				req->id.idiag_if, 0, tbl, NULL); | 
 | #if IS_ENABLED(CONFIG_IPV6) | 
 | 	else if (req->sdiag_family == AF_INET6) | 
 | 		sk = __udp6_lib_lookup(net, | 
 | 				(struct in6_addr *)req->id.idiag_src, | 
 | 				req->id.idiag_sport, | 
 | 				(struct in6_addr *)req->id.idiag_dst, | 
 | 				req->id.idiag_dport, | 
 | 				req->id.idiag_if, 0, tbl, NULL); | 
 | #endif | 
 | 	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) | 
 | 		sk = NULL; | 
 | 	rcu_read_unlock(); | 
 | 	err = -ENOENT; | 
 | 	if (!sk) | 
 | 		goto out_nosk; | 
 |  | 
 | 	err = sock_diag_check_cookie(sk, req->id.idiag_cookie); | 
 | 	if (err) | 
 | 		goto out; | 
 |  | 
 | 	err = -ENOMEM; | 
 | 	rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) + | 
 | 			inet_diag_msg_attrs_size() + | 
 | 			nla_total_size(sizeof(struct inet_diag_meminfo)) + 64, | 
 | 			GFP_KERNEL); | 
 | 	if (!rep) | 
 | 		goto out; | 
 |  | 
 | 	err = inet_sk_diag_fill(sk, NULL, rep, cb, req, 0, | 
 | 				netlink_net_capable(in_skb, CAP_NET_ADMIN)); | 
 | 	if (err < 0) { | 
 | 		WARN_ON(err == -EMSGSIZE); | 
 | 		kfree_skb(rep); | 
 | 		goto out; | 
 | 	} | 
 | 	err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, | 
 | 			      MSG_DONTWAIT); | 
 | 	if (err > 0) | 
 | 		err = 0; | 
 | out: | 
 | 	if (sk) | 
 | 		sock_put(sk); | 
 | out_nosk: | 
 | 	return err; | 
 | } | 
 |  | 
 | static void udp_dump(struct udp_table *table, struct sk_buff *skb, | 
 | 		     struct netlink_callback *cb, | 
 | 		     const struct inet_diag_req_v2 *r) | 
 | { | 
 | 	bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); | 
 | 	struct net *net = sock_net(skb->sk); | 
 | 	struct inet_diag_dump_data *cb_data; | 
 | 	int num, s_num, slot, s_slot; | 
 | 	struct nlattr *bc; | 
 |  | 
 | 	cb_data = cb->data; | 
 | 	bc = cb_data->inet_diag_nla_bc; | 
 | 	s_slot = cb->args[0]; | 
 | 	num = s_num = cb->args[1]; | 
 |  | 
 | 	for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) { | 
 | 		struct udp_hslot *hslot = &table->hash[slot]; | 
 | 		struct sock *sk; | 
 |  | 
 | 		num = 0; | 
 |  | 
 | 		if (hlist_empty(&hslot->head)) | 
 | 			continue; | 
 |  | 
 | 		spin_lock_bh(&hslot->lock); | 
 | 		sk_for_each(sk, &hslot->head) { | 
 | 			struct inet_sock *inet = inet_sk(sk); | 
 |  | 
 | 			if (!net_eq(sock_net(sk), net)) | 
 | 				continue; | 
 | 			if (num < s_num) | 
 | 				goto next; | 
 | 			if (!(r->idiag_states & (1 << sk->sk_state))) | 
 | 				goto next; | 
 | 			if (r->sdiag_family != AF_UNSPEC && | 
 | 					sk->sk_family != r->sdiag_family) | 
 | 				goto next; | 
 | 			if (r->id.idiag_sport != inet->inet_sport && | 
 | 			    r->id.idiag_sport) | 
 | 				goto next; | 
 | 			if (r->id.idiag_dport != inet->inet_dport && | 
 | 			    r->id.idiag_dport) | 
 | 				goto next; | 
 |  | 
 | 			if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) { | 
 | 				spin_unlock_bh(&hslot->lock); | 
 | 				goto done; | 
 | 			} | 
 | next: | 
 | 			num++; | 
 | 		} | 
 | 		spin_unlock_bh(&hslot->lock); | 
 | 	} | 
 | done: | 
 | 	cb->args[0] = slot; | 
 | 	cb->args[1] = num; | 
 | } | 
 |  | 
 | static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, | 
 | 			  const struct inet_diag_req_v2 *r) | 
 | { | 
 | 	udp_dump(&udp_table, skb, cb, r); | 
 | } | 
 |  | 
 | static int udp_diag_dump_one(struct netlink_callback *cb, | 
 | 			     const struct inet_diag_req_v2 *req) | 
 | { | 
 | 	return udp_dump_one(&udp_table, cb, req); | 
 | } | 
 |  | 
 | static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, | 
 | 		void *info) | 
 | { | 
 | 	r->idiag_rqueue = udp_rqueue_get(sk); | 
 | 	r->idiag_wqueue = sk_wmem_alloc_get(sk); | 
 | } | 
 |  | 
 | #ifdef CONFIG_INET_DIAG_DESTROY | 
 | static int __udp_diag_destroy(struct sk_buff *in_skb, | 
 | 			      const struct inet_diag_req_v2 *req, | 
 | 			      struct udp_table *tbl) | 
 | { | 
 | 	struct net *net = sock_net(in_skb->sk); | 
 | 	struct sock *sk; | 
 | 	int err; | 
 |  | 
 | 	rcu_read_lock(); | 
 |  | 
 | 	if (req->sdiag_family == AF_INET) | 
 | 		sk = __udp4_lib_lookup(net, | 
 | 				req->id.idiag_dst[0], req->id.idiag_dport, | 
 | 				req->id.idiag_src[0], req->id.idiag_sport, | 
 | 				req->id.idiag_if, 0, tbl, NULL); | 
 | #if IS_ENABLED(CONFIG_IPV6) | 
 | 	else if (req->sdiag_family == AF_INET6) { | 
 | 		if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) && | 
 | 		    ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src)) | 
 | 			sk = __udp4_lib_lookup(net, | 
 | 					req->id.idiag_dst[3], req->id.idiag_dport, | 
 | 					req->id.idiag_src[3], req->id.idiag_sport, | 
 | 					req->id.idiag_if, 0, tbl, NULL); | 
 |  | 
 | 		else | 
 | 			sk = __udp6_lib_lookup(net, | 
 | 					(struct in6_addr *)req->id.idiag_dst, | 
 | 					req->id.idiag_dport, | 
 | 					(struct in6_addr *)req->id.idiag_src, | 
 | 					req->id.idiag_sport, | 
 | 					req->id.idiag_if, 0, tbl, NULL); | 
 | 	} | 
 | #endif | 
 | 	else { | 
 | 		rcu_read_unlock(); | 
 | 		return -EINVAL; | 
 | 	} | 
 |  | 
 | 	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) | 
 | 		sk = NULL; | 
 |  | 
 | 	rcu_read_unlock(); | 
 |  | 
 | 	if (!sk) | 
 | 		return -ENOENT; | 
 |  | 
 | 	if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) { | 
 | 		sock_put(sk); | 
 | 		return -ENOENT; | 
 | 	} | 
 |  | 
 | 	err = sock_diag_destroy(sk, ECONNABORTED); | 
 |  | 
 | 	sock_put(sk); | 
 |  | 
 | 	return err; | 
 | } | 
 |  | 
 | static int udp_diag_destroy(struct sk_buff *in_skb, | 
 | 			    const struct inet_diag_req_v2 *req) | 
 | { | 
 | 	return __udp_diag_destroy(in_skb, req, &udp_table); | 
 | } | 
 |  | 
 | static int udplite_diag_destroy(struct sk_buff *in_skb, | 
 | 				const struct inet_diag_req_v2 *req) | 
 | { | 
 | 	return __udp_diag_destroy(in_skb, req, &udplite_table); | 
 | } | 
 |  | 
 | #endif | 
 |  | 
 | static const struct inet_diag_handler udp_diag_handler = { | 
 | 	.dump		 = udp_diag_dump, | 
 | 	.dump_one	 = udp_diag_dump_one, | 
 | 	.idiag_get_info  = udp_diag_get_info, | 
 | 	.idiag_type	 = IPPROTO_UDP, | 
 | 	.idiag_info_size = 0, | 
 | #ifdef CONFIG_INET_DIAG_DESTROY | 
 | 	.destroy	 = udp_diag_destroy, | 
 | #endif | 
 | }; | 
 |  | 
 | static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, | 
 | 			      const struct inet_diag_req_v2 *r) | 
 | { | 
 | 	udp_dump(&udplite_table, skb, cb, r); | 
 | } | 
 |  | 
 | static int udplite_diag_dump_one(struct netlink_callback *cb, | 
 | 				 const struct inet_diag_req_v2 *req) | 
 | { | 
 | 	return udp_dump_one(&udplite_table, cb, req); | 
 | } | 
 |  | 
 | static const struct inet_diag_handler udplite_diag_handler = { | 
 | 	.dump		 = udplite_diag_dump, | 
 | 	.dump_one	 = udplite_diag_dump_one, | 
 | 	.idiag_get_info  = udp_diag_get_info, | 
 | 	.idiag_type	 = IPPROTO_UDPLITE, | 
 | 	.idiag_info_size = 0, | 
 | #ifdef CONFIG_INET_DIAG_DESTROY | 
 | 	.destroy	 = udplite_diag_destroy, | 
 | #endif | 
 | }; | 
 |  | 
 | static int __init udp_diag_init(void) | 
 | { | 
 | 	int err; | 
 |  | 
 | 	err = inet_diag_register(&udp_diag_handler); | 
 | 	if (err) | 
 | 		goto out; | 
 | 	err = inet_diag_register(&udplite_diag_handler); | 
 | 	if (err) | 
 | 		goto out_lite; | 
 | out: | 
 | 	return err; | 
 | out_lite: | 
 | 	inet_diag_unregister(&udp_diag_handler); | 
 | 	goto out; | 
 | } | 
 |  | 
 | static void __exit udp_diag_exit(void) | 
 | { | 
 | 	inet_diag_unregister(&udplite_diag_handler); | 
 | 	inet_diag_unregister(&udp_diag_handler); | 
 | } | 
 |  | 
 | module_init(udp_diag_init); | 
 | module_exit(udp_diag_exit); | 
 | MODULE_LICENSE("GPL"); | 
 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */); | 
 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */); |