-
-int tcp_listen_start(struct sock *sk)
-{
- struct inet_opt *inet = inet_sk(sk);
- struct tcp_opt *tp = tcp_sk(sk);
- struct tcp_listen_opt *lopt;
-
- sk->sk_max_ack_backlog = 0;
- sk->sk_ack_backlog = 0;
- tp->accept_queue = tp->accept_queue_tail = NULL;
- tp->syn_wait_lock = RW_LOCK_UNLOCKED;
- tcp_delack_init(tp);
-
- lopt = kmalloc(sizeof(struct tcp_listen_opt), GFP_KERNEL);
- if (!lopt)
- return -ENOMEM;
-
- memset(lopt, 0, sizeof(struct tcp_listen_opt));
- for (lopt->max_qlen_log = 6; ; lopt->max_qlen_log++)
- if ((1 << lopt->max_qlen_log) >= sysctl_max_syn_backlog)
- break;
- get_random_bytes(&lopt->hash_rnd, 4);
-
- write_lock_bh(&tp->syn_wait_lock);
- tp->listen_opt = lopt;
- write_unlock_bh(&tp->syn_wait_lock);
-
- /* There is race window here: we announce ourselves listening,
- * but this transition is still not validated by get_port().
- * It is OK, because this socket enters to hash table only
- * after validation is complete.
- */
- sk->sk_state = TCP_LISTEN;
- if (!sk->sk_prot->get_port(sk, inet->num)) {
- inet->sport = htons(inet->num);
-
- sk_dst_reset(sk);
- sk->sk_prot->hash(sk);
-
- return 0;
- }
-
- sk->sk_state = TCP_CLOSE;
- write_lock_bh(&tp->syn_wait_lock);
- tp->listen_opt = NULL;
- write_unlock_bh(&tp->syn_wait_lock);
- kfree(lopt);
- return -EADDRINUSE;
-}
-
-/*
- * This routine closes sockets which have been at least partially
- * opened, but not yet accepted.
- */
-
-static void tcp_listen_stop (struct sock *sk)
-{
- struct tcp_opt *tp = tcp_sk(sk);
- struct tcp_listen_opt *lopt = tp->listen_opt;
- struct open_request *acc_req = tp->accept_queue;
- struct open_request *req;
- int i;
-
- tcp_delete_keepalive_timer(sk);
-
- /* make all the listen_opt local to us */
- write_lock_bh(&tp->syn_wait_lock);
- tp->listen_opt = NULL;
- write_unlock_bh(&tp->syn_wait_lock);
- tp->accept_queue = tp->accept_queue_tail = NULL;
-
- if (lopt->qlen) {
- for (i = 0; i < TCP_SYNQ_HSIZE; i++) {
- while ((req = lopt->syn_table[i]) != NULL) {
- lopt->syn_table[i] = req->dl_next;
- lopt->qlen--;
- tcp_openreq_free(req);
-
- /* Following specs, it would be better either to send FIN
- * (and enter FIN-WAIT-1, it is normal close)
- * or to send active reset (abort).
- * Certainly, it is pretty dangerous while synflood, but it is
- * bad justification for our negligence 8)
- * To be honest, we are not able to make either
- * of the variants now. --ANK
- */
- }
- }
- }
- BUG_TRAP(!lopt->qlen);
-
- kfree(lopt);
-
- while ((req = acc_req) != NULL) {
- struct sock *child = req->sk;
-
- acc_req = req->dl_next;
-
- local_bh_disable();
- bh_lock_sock(child);
- BUG_TRAP(!sock_owned_by_user(child));
- sock_hold(child);
-
- tcp_disconnect(child, O_NONBLOCK);
-
- sock_orphan(child);
-
- atomic_inc(&tcp_orphan_count);
-
- tcp_destroy_sock(child);
-
- bh_unlock_sock(child);
- local_bh_enable();
- sock_put(child);
-
- sk_acceptq_removed(sk);
- tcp_openreq_fastfree(req);
- }
- BUG_TRAP(!sk->sk_ack_backlog);
-}
-
-static inline void tcp_mark_push(struct tcp_opt *tp, struct sk_buff *skb)