// SPDX-License-Identifier: GPL-2.0-or-later
/* L2TPv3 IP encapsulation support
 *
 * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <asm/ioctls.h>
#include <linux/icmp.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/random.h>
#include <linux/socket.h>
#include <linux/l2tp.h>
#include <linux/in.h>
#include <net/sock.h>
#include <net/ip.h>
#include <net/icmp.h>
#include <net/udp.h>
#include <net/inet_common.h>
#include <net/tcp_states.h>
#include <net/protocol.h>
#include <net/xfrm.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>

#include "l2tp_core.h"

/* per-net private data for this module */
static unsigned int l2tp_ip_net_id;
struct l2tp_ip_net {
        rwlock_t l2tp_ip_lock;
        struct hlist_head l2tp_ip_table;
        struct hlist_head l2tp_ip_bind_table;
};

struct l2tp_ip_sock {
        /* inet_sock has to be the first member of l2tp_ip_sock */
        struct inet_sock        inet;

        u32                     conn_id;
        u32                     peer_conn_id;
};

static struct l2tp_ip_sock *l2tp_ip_sk(const struct sock *sk)
{
        return (struct l2tp_ip_sock *)sk;
}

static struct l2tp_ip_net *l2tp_ip_pernet(const struct net *net)
{
        return net_generic(net, l2tp_ip_net_id);
}

static struct sock *__l2tp_ip_bind_lookup(const struct net *net, __be32 laddr,
                                          __be32 raddr, int dif, u32 tunnel_id)
{
        struct l2tp_ip_net *pn = l2tp_ip_pernet(net);
        struct sock *sk;

        sk_for_each_bound(sk, &pn->l2tp_ip_bind_table) {
                const struct l2tp_ip_sock *l2tp = l2tp_ip_sk(sk);
                const struct inet_sock *inet = inet_sk(sk);
                int bound_dev_if;

                if (!net_eq(sock_net(sk), net))
                        continue;

                bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
                if (bound_dev_if && dif && bound_dev_if != dif)
                        continue;

                if (inet->inet_rcv_saddr && laddr &&
                    inet->inet_rcv_saddr != laddr)
                        continue;

                if (inet->inet_daddr && raddr && inet->inet_daddr != raddr)
                        continue;

                if (l2tp->conn_id != tunnel_id)
                        continue;

                goto found;
        }

        sk = NULL;
found:
        return sk;
}

/* When processing receive frames, there are two cases to
 * consider. Data frames consist of a non-zero session-id and an
 * optional cookie. Control frames consist of a regular L2TP header
 * preceded by 32-bits of zeros.
 *
 * L2TPv3 Session Header Over IP
 *
 *  0                   1                   2                   3
 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |                           Session ID                          |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |               Cookie (optional, maximum 64 bits)...
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *                                                                 |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * L2TPv3 Control Message Header Over IP
 *
 *  0                   1                   2                   3
 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |                      (32 bits of zeros)                       |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |T|L|x|x|S|x|x|x|x|x|x|x|  Ver  |             Length            |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |                     Control Connection ID                     |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |               Ns              |               Nr              |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * All control frames are passed to userspace.
 */
static int l2tp_ip_recv(struct sk_buff *skb)
{
        struct net *net = dev_net(skb->dev);
        struct l2tp_ip_net *pn;
        struct sock *sk;
        u32 session_id;
        u32 tunnel_id;
        unsigned char *ptr, *optr;
        struct l2tp_session *session;
        struct l2tp_tunnel *tunnel = NULL;
        struct iphdr *iph;

        pn = l2tp_ip_pernet(net);

        if (!pskb_may_pull(skb, 4))
                goto discard;

        /* Point to L2TP header */
        optr = skb->data;
        ptr = skb->data;
        session_id = ntohl(*((__be32 *)ptr));
        ptr += 4;

        /* RFC3931: L2TP/IP packets have the first 4 bytes containing
         * the session_id. If it is 0, the packet is a L2TP control
         * frame and the session_id value can be discarded.
         */
        if (session_id == 0) {
                __skb_pull(skb, 4);
                goto pass_up;
        }

        /* Ok, this is a data packet. Lookup the session. */
        session = l2tp_v3_session_get(net, NULL, session_id);
        if (!session)
                goto discard;

        tunnel = session->tunnel;
        if (!tunnel)
                goto discard_sess;

        if (l2tp_v3_ensure_opt_in_linear(session, skb, &ptr, &optr))
                goto discard_sess;

        l2tp_recv_common(session, skb, ptr, optr, 0, skb->len);
        l2tp_session_put(session);

        return 0;

pass_up:
        /* Get the tunnel_id from the L2TP header */
        if (!pskb_may_pull(skb, 12))
                goto discard;

        if ((skb->data[0] & 0xc0) != 0xc0)
                goto discard;

        tunnel_id = ntohl(*(__be32 *)&skb->data[4]);
        iph = (struct iphdr *)skb_network_header(skb);

        read_lock_bh(&pn->l2tp_ip_lock);
        sk = __l2tp_ip_bind_lookup(net, iph->daddr, iph->saddr, inet_iif(skb),
                                   tunnel_id);
        if (!sk) {
                read_unlock_bh(&pn->l2tp_ip_lock);
                goto discard;
        }
        sock_hold(sk);
        read_unlock_bh(&pn->l2tp_ip_lock);

        if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
                goto discard_put;

        nf_reset_ct(skb);

        return sk_receive_skb(sk, skb, 1);

discard_sess:
        l2tp_session_put(session);
        goto discard;

discard_put:
        sock_put(sk);

discard:
        kfree_skb(skb);
        return 0;
}

static int l2tp_ip_hash(struct sock *sk)
{
        struct l2tp_ip_net *pn = l2tp_ip_pernet(sock_net(sk));

        if (sk_unhashed(sk)) {
                write_lock_bh(&pn->l2tp_ip_lock);
                sk_add_node(sk, &pn->l2tp_ip_table);
                write_unlock_bh(&pn->l2tp_ip_lock);
        }
        return 0;
}

static void l2tp_ip_unhash(struct sock *sk)
{
        struct l2tp_ip_net *pn = l2tp_ip_pernet(sock_net(sk));

        if (sk_unhashed(sk))
                return;
        write_lock_bh(&pn->l2tp_ip_lock);
        sk_del_node_init(sk);
        write_unlock_bh(&pn->l2tp_ip_lock);
}

static int l2tp_ip_open(struct sock *sk)
{
        /* Prevent autobind. We don't have ports. */
        inet_sk(sk)->inet_num = IPPROTO_L2TP;

        l2tp_ip_hash(sk);
        return 0;
}

static void l2tp_ip_close(struct sock *sk, long timeout)
{
        struct l2tp_ip_net *pn = l2tp_ip_pernet(sock_net(sk));

        write_lock_bh(&pn->l2tp_ip_lock);
        hlist_del_init(&sk->sk_bind_node);
        sk_del_node_init(sk);
        write_unlock_bh(&pn->l2tp_ip_lock);
        sk_common_release(sk);
}

static void l2tp_ip_destroy_sock(struct sock *sk)
{
        struct l2tp_tunnel *tunnel;

        __skb_queue_purge(&sk->sk_write_queue);

        tunnel = l2tp_sk_to_tunnel(sk);
        if (tunnel) {
                l2tp_tunnel_delete(tunnel);
                l2tp_tunnel_put(tunnel);
        }
}

static int l2tp_ip_bind(struct sock *sk, struct sockaddr_unsized *uaddr,
                        int addr_len)
{
        struct inet_sock *inet = inet_sk(sk);
        struct sockaddr_l2tpip *addr = (struct sockaddr_l2tpip *)uaddr;
        struct net *net = sock_net(sk);
        struct l2tp_ip_net *pn;
        int ret;
        int chk_addr_ret;

        if (addr_len < sizeof(struct sockaddr_l2tpip))
                return -EINVAL;
        if (addr->l2tp_family != AF_INET)
                return -EINVAL;

        lock_sock(sk);

        ret = -EINVAL;
        if (!sock_flag(sk, SOCK_ZAPPED))
                goto out;

        if (sk->sk_state != TCP_CLOSE)
                goto out;

        chk_addr_ret = inet_addr_type(net, addr->l2tp_addr.s_addr);
        ret = -EADDRNOTAVAIL;
        if (addr->l2tp_addr.s_addr && chk_addr_ret != RTN_LOCAL &&
            chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST)
                goto out;

        if (addr->l2tp_addr.s_addr) {
                inet->inet_rcv_saddr = addr->l2tp_addr.s_addr;
                inet->inet_saddr = addr->l2tp_addr.s_addr;
        }
        if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
                inet->inet_saddr = 0;  /* Use device */

        pn = l2tp_ip_pernet(net);
        write_lock_bh(&pn->l2tp_ip_lock);
        if (__l2tp_ip_bind_lookup(net, addr->l2tp_addr.s_addr, 0,
                                  sk->sk_bound_dev_if, addr->l2tp_conn_id)) {
                write_unlock_bh(&pn->l2tp_ip_lock);
                ret = -EADDRINUSE;
                goto out;
        }

        sk_dst_reset(sk);
        l2tp_ip_sk(sk)->conn_id = addr->l2tp_conn_id;

        sk_add_bind_node(sk, &pn->l2tp_ip_bind_table);
        sk_del_node_init(sk);
        write_unlock_bh(&pn->l2tp_ip_lock);

        ret = 0;
        sock_reset_flag(sk, SOCK_ZAPPED);

out:
        release_sock(sk);

        return ret;
}

static int l2tp_ip_connect(struct sock *sk, struct sockaddr_unsized *uaddr,
                           int addr_len)
{
        struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *)uaddr;
        struct l2tp_ip_net *pn = l2tp_ip_pernet(sock_net(sk));
        int rc;

        if (addr_len < sizeof(*lsa))
                return -EINVAL;

        if (ipv4_is_multicast(lsa->l2tp_addr.s_addr))
                return -EINVAL;

        lock_sock(sk);

        /* Must bind first - autobinding does not work */
        if (sock_flag(sk, SOCK_ZAPPED)) {
                rc = -EINVAL;
                goto out_sk;
        }

        rc = __ip4_datagram_connect(sk, uaddr, addr_len);
        if (rc < 0)
                goto out_sk;

        l2tp_ip_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;

        write_lock_bh(&pn->l2tp_ip_lock);
        hlist_del_init(&sk->sk_bind_node);
        sk_add_bind_node(sk, &pn->l2tp_ip_bind_table);
        write_unlock_bh(&pn->l2tp_ip_lock);

out_sk:
        release_sock(sk);

        return rc;
}

static int l2tp_ip_disconnect(struct sock *sk, int flags)
{
        if (sock_flag(sk, SOCK_ZAPPED))
                return 0;

        return __udp_disconnect(sk, flags);
}

static int l2tp_ip_getname(struct socket *sock, struct sockaddr *uaddr,
                           int peer)
{
        struct sock *sk         = sock->sk;
        struct inet_sock *inet  = inet_sk(sk);
        struct l2tp_ip_sock *lsk = l2tp_ip_sk(sk);
        struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *)uaddr;

        memset(lsa, 0, sizeof(*lsa));
        lsa->l2tp_family = AF_INET;
        if (peer) {
                if (!inet->inet_dport)
                        return -ENOTCONN;
                lsa->l2tp_conn_id = lsk->peer_conn_id;
                lsa->l2tp_addr.s_addr = inet->inet_daddr;
        } else {
                __be32 addr = inet->inet_rcv_saddr;

                if (!addr)
                        addr = inet->inet_saddr;
                lsa->l2tp_conn_id = lsk->conn_id;
                lsa->l2tp_addr.s_addr = addr;
        }
        return sizeof(*lsa);
}

static int l2tp_ip_backlog_recv(struct sock *sk, struct sk_buff *skb)
{
        int rc;

        /* Charge it to the socket, dropping if the queue is full. */
        rc = sock_queue_rcv_skb(sk, skb);
        if (rc < 0)
                goto drop;

        return 0;

drop:
        IP_INC_STATS(sock_net(sk), IPSTATS_MIB_INDISCARDS);
        kfree_skb(skb);
        return 0;
}

/* Userspace will call sendmsg() on the tunnel socket to send L2TP
 * control frames.
 */
static int l2tp_ip_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
{
        struct sk_buff *skb;
        int rc;
        struct inet_sock *inet = inet_sk(sk);
        struct rtable *rt = NULL;
        int connected = 0;
        __be32 daddr;

        lock_sock(sk);

        rc = -ENOTCONN;
        if (sock_flag(sk, SOCK_DEAD))
                goto out;

        /* Get and verify the address. */
        if (msg->msg_name) {
                DECLARE_SOCKADDR(struct sockaddr_l2tpip *, lip, msg->msg_name);

                rc = -EINVAL;
                if (msg->msg_namelen < sizeof(*lip))
                        goto out;

                if (lip->l2tp_family != AF_INET) {
                        rc = -EAFNOSUPPORT;
                        if (lip->l2tp_family != AF_UNSPEC)
                                goto out;
                }

                daddr = lip->l2tp_addr.s_addr;
        } else {
                rc = -EDESTADDRREQ;
                if (sk->sk_state != TCP_ESTABLISHED)
                        goto out;

                connected = 1;
        }

        /* Allocate a socket buffer */
        rc = -ENOMEM;
        skb = sock_wmalloc(sk, 2 + NET_SKB_PAD + sizeof(struct iphdr) +
                           4 + len, 0, GFP_KERNEL);
        if (!skb)
                goto error;

        /* Reserve space for headers, putting IP header on 4-byte boundary. */
        skb_reserve(skb, 2 + NET_SKB_PAD);
        skb_reset_network_header(skb);
        skb_reserve(skb, sizeof(struct iphdr));
        skb_reset_transport_header(skb);

        /* Insert 0 session_id */
        *((__be32 *)skb_put(skb, 4)) = 0;

        /* Copy user data into skb */
        rc = memcpy_from_msg(skb_put(skb, len), msg, len);
        if (rc < 0) {
                kfree_skb(skb);
                goto error;
        }

        if (connected)
                rt = dst_rtable(__sk_dst_check(sk, 0));

        rcu_read_lock();
        if (!rt) {
                struct flowi4 *fl4 = &inet->cork.fl.u.ip4;

                inet_sk_init_flowi4(inet, fl4);

                /* Overwrite ->daddr if msg->msg_name was provided */
                if (!connected)
                        fl4->daddr = daddr;

                /* If this fails, retransmit mechanism of transport layer will
                 * keep trying until route appears or the connection times
                 * itself out.
                 */
                rt = ip_route_output_flow(sock_net(sk), fl4, sk);
                if (IS_ERR(rt))
                        goto no_route;
                if (connected) {
                        sk_setup_caps(sk, &rt->dst);
                } else {
                        skb_dst_set(skb, &rt->dst);
                        goto xmit;
                }
        }

        /* We don't need to clone dst here, it is guaranteed to not disappear.
         *  __dev_xmit_skb() might force a refcount if needed.
         */
        skb_dst_set_noref(skb, &rt->dst);

xmit:
        /* Queue the packet to IP for output */
        rc = ip_queue_xmit(sk, skb, &inet->cork.fl);
        rcu_read_unlock();

error:
        if (rc >= 0)
                rc = len;

out:
        release_sock(sk);
        return rc;

no_route:
        rcu_read_unlock();
        IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
        kfree_skb(skb);
        rc = -EHOSTUNREACH;
        goto out;
}

static int l2tp_ip_recvmsg(struct sock *sk, struct msghdr *msg,
                           size_t len, int flags, int *addr_len)
{
        struct inet_sock *inet = inet_sk(sk);
        size_t copied = 0;
        int err = -EOPNOTSUPP;
        DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
        struct sk_buff *skb;

        if (flags & MSG_OOB)
                goto out;

        skb = skb_recv_datagram(sk, flags, &err);
        if (!skb)
                goto out;

        copied = skb->len;
        if (len < copied) {
                msg->msg_flags |= MSG_TRUNC;
                copied = len;
        }

        err = skb_copy_datagram_msg(skb, 0, msg, copied);
        if (err)
                goto done;

        sock_recv_timestamp(msg, sk, skb);

        /* Copy the address. */
        if (sin) {
                sin->sin_family = AF_INET;
                sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
                sin->sin_port = 0;
                memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
                *addr_len = sizeof(*sin);
        }
        if (inet_cmsg_flags(inet))
                ip_cmsg_recv(msg, skb);
        if (flags & MSG_TRUNC)
                copied = skb->len;
done:
        skb_free_datagram(sk, skb);
out:
        return err ? err : copied;
}

int l2tp_ioctl(struct sock *sk, int cmd, int *karg)
{
        struct sk_buff *skb;

        switch (cmd) {
        case SIOCOUTQ:
                *karg = sk_wmem_alloc_get(sk);
                break;
        case SIOCINQ:
                spin_lock_bh(&sk->sk_receive_queue.lock);
                skb = skb_peek(&sk->sk_receive_queue);
                *karg = skb ? skb->len : 0;
                spin_unlock_bh(&sk->sk_receive_queue.lock);
                break;

        default:
                return -ENOIOCTLCMD;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(l2tp_ioctl);

static struct proto l2tp_ip_prot = {
        .name              = "L2TP/IP",
        .owner             = THIS_MODULE,
        .init              = l2tp_ip_open,
        .close             = l2tp_ip_close,
        .bind              = l2tp_ip_bind,
        .connect           = l2tp_ip_connect,
        .disconnect        = l2tp_ip_disconnect,
        .ioctl             = l2tp_ioctl,
        .destroy           = l2tp_ip_destroy_sock,
        .setsockopt        = ip_setsockopt,
        .getsockopt        = ip_getsockopt,
        .sendmsg           = l2tp_ip_sendmsg,
        .recvmsg           = l2tp_ip_recvmsg,
        .backlog_rcv       = l2tp_ip_backlog_recv,
        .hash              = l2tp_ip_hash,
        .unhash            = l2tp_ip_unhash,
        .obj_size          = sizeof(struct l2tp_ip_sock),
};

static const struct proto_ops l2tp_ip_ops = {
        .family            = PF_INET,
        .owner             = THIS_MODULE,
        .release           = inet_release,
        .bind              = inet_bind,
        .connect           = inet_dgram_connect,
        .socketpair        = sock_no_socketpair,
        .accept            = sock_no_accept,
        .getname           = l2tp_ip_getname,
        .poll              = datagram_poll,
        .ioctl             = inet_ioctl,
        .gettstamp         = sock_gettstamp,
        .listen            = sock_no_listen,
        .shutdown          = inet_shutdown,
        .setsockopt        = sock_common_setsockopt,
        .getsockopt        = sock_common_getsockopt,
        .sendmsg           = inet_sendmsg,
        .recvmsg           = sock_common_recvmsg,
        .mmap              = sock_no_mmap,
};

static struct inet_protosw l2tp_ip_protosw = {
        .type           = SOCK_DGRAM,
        .protocol       = IPPROTO_L2TP,
        .prot           = &l2tp_ip_prot,
        .ops            = &l2tp_ip_ops,
};

static struct net_protocol l2tp_ip_protocol __read_mostly = {
        .handler        = l2tp_ip_recv,
};

static __net_init int l2tp_ip_init_net(struct net *net)
{
        struct l2tp_ip_net *pn = net_generic(net, l2tp_ip_net_id);

        rwlock_init(&pn->l2tp_ip_lock);
        INIT_HLIST_HEAD(&pn->l2tp_ip_table);
        INIT_HLIST_HEAD(&pn->l2tp_ip_bind_table);
        return 0;
}

static __net_exit void l2tp_ip_exit_net(struct net *net)
{
        struct l2tp_ip_net *pn = l2tp_ip_pernet(net);

        write_lock_bh(&pn->l2tp_ip_lock);
        WARN_ON_ONCE(hlist_count_nodes(&pn->l2tp_ip_table) != 0);
        WARN_ON_ONCE(hlist_count_nodes(&pn->l2tp_ip_bind_table) != 0);
        write_unlock_bh(&pn->l2tp_ip_lock);
}

static struct pernet_operations l2tp_ip_net_ops = {
        .init = l2tp_ip_init_net,
        .exit = l2tp_ip_exit_net,
        .id   = &l2tp_ip_net_id,
        .size = sizeof(struct l2tp_ip_net),
};

static int __init l2tp_ip_init(void)
{
        int err;

        pr_info("L2TP IP encapsulation support (L2TPv3)\n");

        err = register_pernet_device(&l2tp_ip_net_ops);
        if (err)
                goto out;

        err = proto_register(&l2tp_ip_prot, 1);
        if (err != 0)
                goto out1;

        err = inet_add_protocol(&l2tp_ip_protocol, IPPROTO_L2TP);
        if (err)
                goto out2;

        inet_register_protosw(&l2tp_ip_protosw);
        return 0;

out2:
        proto_unregister(&l2tp_ip_prot);
out1:
        unregister_pernet_device(&l2tp_ip_net_ops);
out:
        return err;
}

static void __exit l2tp_ip_exit(void)
{
        inet_unregister_protosw(&l2tp_ip_protosw);
        inet_del_protocol(&l2tp_ip_protocol, IPPROTO_L2TP);
        proto_unregister(&l2tp_ip_prot);
        unregister_pernet_device(&l2tp_ip_net_ops);
}

module_init(l2tp_ip_init);
module_exit(l2tp_ip_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
MODULE_DESCRIPTION("L2TP over IP");
MODULE_VERSION("1.0");

/* Use the values of SOCK_DGRAM (2) as type and IPPROTO_L2TP (115) as protocol,
 * because __stringify doesn't like enums
 */
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 115, 2);
MODULE_ALIAS_NET_PF_PROTO(PF_INET, 115);