| /* |
| * INET An implementation of the TCP/IP protocol suite for the LINUX |
| * operating system. INET is implemented using the BSD Socket |
| * interface as the means of communication with the user level. |
| * |
| * Support for INET connection oriented protocols. |
| * |
| * Authors: See the TCP sources |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or(at your option) any later version. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/jhash.h> |
| |
| #include <net/inet_connection_sock.h> |
| #include <net/inet_hashtables.h> |
| #include <net/inet_timewait_sock.h> |
| #include <net/ip.h> |
| #include <net/route.h> |
| #include <net/tcp_states.h> |
| #include <net/xfrm.h> |
| |
| #ifdef INET_CSK_DEBUG |
| const char inet_csk_timer_bug_msg[] = "inet_csk BUG: unknown timer value\n"; |
| EXPORT_SYMBOL(inet_csk_timer_bug_msg); |
| #endif |
| |
| /* |
| * This struct holds the first and last local port number. |
| */ |
| struct local_ports sysctl_local_ports __read_mostly = { |
| .lock = __SEQLOCK_UNLOCKED(sysctl_local_ports.lock), |
| .range = { 32768, 61000 }, |
| }; |
| |
| unsigned long *sysctl_local_reserved_ports; |
| EXPORT_SYMBOL(sysctl_local_reserved_ports); |
| |
| void inet_get_local_port_range(int *low, int *high) |
| { |
| unsigned int seq; |
| |
| do { |
| seq = read_seqbegin(&sysctl_local_ports.lock); |
| |
| *low = sysctl_local_ports.range[0]; |
| *high = sysctl_local_ports.range[1]; |
| } while (read_seqretry(&sysctl_local_ports.lock, seq)); |
| } |
| EXPORT_SYMBOL(inet_get_local_port_range); |
| |
| int inet_csk_bind_conflict(const struct sock *sk, |
| const struct inet_bind_bucket *tb, bool relax) |
| { |
| struct sock *sk2; |
| int reuse = sk->sk_reuse; |
| int reuseport = sk->sk_reuseport; |
| kuid_t uid = sock_i_uid((struct sock *)sk); |
| |
| /* |
| * Unlike other sk lookup places we do not check |
| * for sk_net here, since _all_ the socks listed |
| * in tb->owners list belong to the same net - the |
| * one this bucket belongs to. |
| */ |
| |
| sk_for_each_bound(sk2, &tb->owners) { |
| if (sk != sk2 && |
| !inet_v6_ipv6only(sk2) && |
| (!sk->sk_bound_dev_if || |
| !sk2->sk_bound_dev_if || |
| sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) { |
| if ((!reuse || !sk2->sk_reuse || |
| sk2->sk_state == TCP_LISTEN) && |
| (!reuseport || !sk2->sk_reuseport || |
| (sk2->sk_state != TCP_TIME_WAIT && |
| !uid_eq(uid, sock_i_uid(sk2))))) { |
| const __be32 sk2_rcv_saddr = sk_rcv_saddr(sk2); |
| if (!sk2_rcv_saddr || !sk_rcv_saddr(sk) || |
| sk2_rcv_saddr == sk_rcv_saddr(sk)) |
| break; |
| } |
| if (!relax && reuse && sk2->sk_reuse && |
| sk2->sk_state != TCP_LISTEN) { |
| const __be32 sk2_rcv_saddr = sk_rcv_saddr(sk2); |
| |
| if (!sk2_rcv_saddr || !sk_rcv_saddr(sk) || |
| sk2_rcv_saddr == sk_rcv_saddr(sk)) |
| break; |
| } |
| } |
| } |
| return sk2 != NULL; |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_bind_conflict); |
| |
| /* Obtain a reference to a local port for the given sock, |
| * if snum is zero it means select any available local port. |
| */ |
| int inet_csk_get_port(struct sock *sk, unsigned short snum) |
| { |
| struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo; |
| struct inet_bind_hashbucket *head; |
| struct inet_bind_bucket *tb; |
| int ret, attempts = 5; |
| struct net *net = sock_net(sk); |
| int smallest_size = -1, smallest_rover; |
| kuid_t uid = sock_i_uid(sk); |
| |
| local_bh_disable(); |
| if (!snum) { |
| int remaining, rover, low, high; |
| |
| again: |
| inet_get_local_port_range(&low, &high); |
| remaining = (high - low) + 1; |
| smallest_rover = rover = net_random() % remaining + low; |
| |
| smallest_size = -1; |
| do { |
| if (inet_is_reserved_local_port(rover)) |
| goto next_nolock; |
| head = &hashinfo->bhash[inet_bhashfn(net, rover, |
| hashinfo->bhash_size)]; |
| spin_lock(&head->lock); |
| inet_bind_bucket_for_each(tb, &head->chain) |
| if (net_eq(ib_net(tb), net) && tb->port == rover) { |
| if (((tb->fastreuse > 0 && |
| sk->sk_reuse && |
| sk->sk_state != TCP_LISTEN) || |
| (tb->fastreuseport > 0 && |
| sk->sk_reuseport && |
| uid_eq(tb->fastuid, uid))) && |
| (tb->num_owners < smallest_size || smallest_size == -1)) { |
| smallest_size = tb->num_owners; |
| smallest_rover = rover; |
| if (atomic_read(&hashinfo->bsockets) > (high - low) + 1 && |
| !inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, false)) { |
| snum = smallest_rover; |
| goto tb_found; |
| } |
| } |
| if (!inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, false)) { |
| snum = rover; |
| goto tb_found; |
| } |
| goto next; |
| } |
| break; |
| next: |
| spin_unlock(&head->lock); |
| next_nolock: |
| if (++rover > high) |
| rover = low; |
| } while (--remaining > 0); |
| |
| /* Exhausted local port range during search? It is not |
| * possible for us to be holding one of the bind hash |
| * locks if this test triggers, because if 'remaining' |
| * drops to zero, we broke out of the do/while loop at |
| * the top level, not from the 'break;' statement. |
| */ |
| ret = 1; |
| if (remaining <= 0) { |
| if (smallest_size != -1) { |
| snum = smallest_rover; |
| goto have_snum; |
| } |
| goto fail; |
| } |
| /* OK, here is the one we will use. HEAD is |
| * non-NULL and we hold it's mutex. |
| */ |
| snum = rover; |
| } else { |
| have_snum: |
| head = &hashinfo->bhash[inet_bhashfn(net, snum, |
| hashinfo->bhash_size)]; |
| spin_lock(&head->lock); |
| inet_bind_bucket_for_each(tb, &head->chain) |
| if (net_eq(ib_net(tb), net) && tb->port == snum) |
| goto tb_found; |
| } |
| tb = NULL; |
| goto tb_not_found; |
| tb_found: |
| if (!hlist_empty(&tb->owners)) { |
| if (sk->sk_reuse == SK_FORCE_REUSE) |
| goto success; |
| |
| if (((tb->fastreuse > 0 && |
| sk->sk_reuse && sk->sk_state != TCP_LISTEN) || |
| (tb->fastreuseport > 0 && |
| sk->sk_reuseport && uid_eq(tb->fastuid, uid))) && |
| smallest_size == -1) { |
| goto success; |
| } else { |
| ret = 1; |
| if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, true)) { |
| if (((sk->sk_reuse && sk->sk_state != TCP_LISTEN) || |
| (tb->fastreuseport > 0 && |
| sk->sk_reuseport && uid_eq(tb->fastuid, uid))) && |
| smallest_size != -1 && --attempts >= 0) { |
| spin_unlock(&head->lock); |
| goto again; |
| } |
| |
| goto fail_unlock; |
| } |
| } |
| } |
| tb_not_found: |
| ret = 1; |
| if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep, |
| net, head, snum)) == NULL) |
| goto fail_unlock; |
| if (hlist_empty(&tb->owners)) { |
| if (sk->sk_reuse && sk->sk_state != TCP_LISTEN) |
| tb->fastreuse = 1; |
| else |
| tb->fastreuse = 0; |
| if (sk->sk_reuseport) { |
| tb->fastreuseport = 1; |
| tb->fastuid = uid; |
| } else |
| tb->fastreuseport = 0; |
| } else { |
| if (tb->fastreuse && |
| (!sk->sk_reuse || sk->sk_state == TCP_LISTEN)) |
| tb->fastreuse = 0; |
| if (tb->fastreuseport && |
| (!sk->sk_reuseport || !uid_eq(tb->fastuid, uid))) |
| tb->fastreuseport = 0; |
| } |
| success: |
| if (!inet_csk(sk)->icsk_bind_hash) |
| inet_bind_hash(sk, tb, snum); |
| WARN_ON(inet_csk(sk)->icsk_bind_hash != tb); |
| ret = 0; |
| |
| fail_unlock: |
| spin_unlock(&head->lock); |
| fail: |
| local_bh_enable(); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_get_port); |
| |
| /* |
| * Wait for an incoming connection, avoid race conditions. This must be called |
| * with the socket locked. |
| */ |
| static int inet_csk_wait_for_connect(struct sock *sk, long timeo) |
| { |
| struct inet_connection_sock *icsk = inet_csk(sk); |
| DEFINE_WAIT(wait); |
| int err; |
| |
| /* |
| * True wake-one mechanism for incoming connections: only |
| * one process gets woken up, not the 'whole herd'. |
| * Since we do not 'race & poll' for established sockets |
| * anymore, the common case will execute the loop only once. |
| * |
| * Subtle issue: "add_wait_queue_exclusive()" will be added |
| * after any current non-exclusive waiters, and we know that |
| * it will always _stay_ after any new non-exclusive waiters |
| * because all non-exclusive waiters are added at the |
| * beginning of the wait-queue. As such, it's ok to "drop" |
| * our exclusiveness temporarily when we get woken up without |
| * having to remove and re-insert us on the wait queue. |
| */ |
| for (;;) { |
| prepare_to_wait_exclusive(sk_sleep(sk), &wait, |
| TASK_INTERRUPTIBLE); |
| release_sock(sk); |
| if (reqsk_queue_empty(&icsk->icsk_accept_queue)) |
| timeo = schedule_timeout(timeo); |
| lock_sock(sk); |
| err = 0; |
| if (!reqsk_queue_empty(&icsk->icsk_accept_queue)) |
| break; |
| err = -EINVAL; |
| if (sk->sk_state != TCP_LISTEN) |
| break; |
| err = sock_intr_errno(timeo); |
| if (signal_pending(current)) |
| break; |
| err = -EAGAIN; |
| if (!timeo) |
| break; |
| } |
| finish_wait(sk_sleep(sk), &wait); |
| return err; |
| } |
| |
| /* |
| * This will accept the next outstanding connection. |
| */ |
| struct sock *inet_csk_accept(struct sock *sk, int flags, int *err) |
| { |
| struct inet_connection_sock *icsk = inet_csk(sk); |
| struct request_sock_queue *queue = &icsk->icsk_accept_queue; |
| struct sock *newsk; |
| struct request_sock *req; |
| int error; |
| |
| lock_sock(sk); |
| |
| /* We need to make sure that this socket is listening, |
| * and that it has something pending. |
| */ |
| error = -EINVAL; |
| if (sk->sk_state != TCP_LISTEN) |
| goto out_err; |
| |
| /* Find already established connection */ |
| if (reqsk_queue_empty(queue)) { |
| long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); |
| |
| /* If this is a non blocking socket don't sleep */ |
| error = -EAGAIN; |
| if (!timeo) |
| goto out_err; |
| |
| error = inet_csk_wait_for_connect(sk, timeo); |
| if (error) |
| goto out_err; |
| } |
| req = reqsk_queue_remove(queue); |
| newsk = req->sk; |
| |
| sk_acceptq_removed(sk); |
| if (sk->sk_protocol == IPPROTO_TCP && queue->fastopenq != NULL) { |
| spin_lock_bh(&queue->fastopenq->lock); |
| if (tcp_rsk(req)->listener) { |
| /* We are still waiting for the final ACK from 3WHS |
| * so can't free req now. Instead, we set req->sk to |
| * NULL to signify that the child socket is taken |
| * so reqsk_fastopen_remove() will free the req |
| * when 3WHS finishes (or is aborted). |
| */ |
| req->sk = NULL; |
| req = NULL; |
| } |
| spin_unlock_bh(&queue->fastopenq->lock); |
| } |
| out: |
| release_sock(sk); |
| if (req) |
| __reqsk_free(req); |
| return newsk; |
| out_err: |
| newsk = NULL; |
| req = NULL; |
| *err = error; |
| goto out; |
| } |
| EXPORT_SYMBOL(inet_csk_accept); |
| |
| /* |
| * Using different timers for retransmit, delayed acks and probes |
| * We may wish use just one timer maintaining a list of expire jiffies |
| * to optimize. |
| */ |
| void inet_csk_init_xmit_timers(struct sock *sk, |
| void (*retransmit_handler)(unsigned long), |
| void (*delack_handler)(unsigned long), |
| void (*keepalive_handler)(unsigned long)) |
| { |
| struct inet_connection_sock *icsk = inet_csk(sk); |
| |
| setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler, |
| (unsigned long)sk); |
| setup_timer(&icsk->icsk_delack_timer, delack_handler, |
| (unsigned long)sk); |
| setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk); |
| icsk->icsk_pending = icsk->icsk_ack.pending = 0; |
| } |
| EXPORT_SYMBOL(inet_csk_init_xmit_timers); |
| |
| void inet_csk_clear_xmit_timers(struct sock *sk) |
| { |
| struct inet_connection_sock *icsk = inet_csk(sk); |
| |
| icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0; |
| |
| sk_stop_timer(sk, &icsk->icsk_retransmit_timer); |
| sk_stop_timer(sk, &icsk->icsk_delack_timer); |
| sk_stop_timer(sk, &sk->sk_timer); |
| } |
| EXPORT_SYMBOL(inet_csk_clear_xmit_timers); |
| |
| void inet_csk_delete_keepalive_timer(struct sock *sk) |
| { |
| sk_stop_timer(sk, &sk->sk_timer); |
| } |
| EXPORT_SYMBOL(inet_csk_delete_keepalive_timer); |
| |
| void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len) |
| { |
| sk_reset_timer(sk, &sk->sk_timer, jiffies + len); |
| } |
| EXPORT_SYMBOL(inet_csk_reset_keepalive_timer); |
| |
| struct dst_entry *inet_csk_route_req(struct sock *sk, |
| struct flowi4 *fl4, |
| const struct request_sock *req) |
| { |
| struct rtable *rt; |
| const struct inet_request_sock *ireq = inet_rsk(req); |
| struct ip_options_rcu *opt = inet_rsk(req)->opt; |
| struct net *net = sock_net(sk); |
| int flags = inet_sk_flowi_flags(sk); |
| |
| flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark, |
| RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE, |
| sk->sk_protocol, |
| flags, |
| (opt && opt->opt.srr) ? opt->opt.faddr : ireq->rmt_addr, |
| ireq->loc_addr, ireq->rmt_port, inet_sk(sk)->inet_sport); |
| security_req_classify_flow(req, flowi4_to_flowi(fl4)); |
| rt = ip_route_output_flow(net, fl4, sk); |
| if (IS_ERR(rt)) |
| goto no_route; |
| if (opt && opt->opt.is_strictroute && rt->rt_uses_gateway) |
| goto route_err; |
| return &rt->dst; |
| |
| route_err: |
| ip_rt_put(rt); |
| no_route: |
| IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); |
| return NULL; |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_route_req); |
| |
| struct dst_entry *inet_csk_route_child_sock(struct sock *sk, |
| struct sock *newsk, |
| const struct request_sock *req) |
| { |
| const struct inet_request_sock *ireq = inet_rsk(req); |
| struct inet_sock *newinet = inet_sk(newsk); |
| struct ip_options_rcu *opt; |
| struct net *net = sock_net(sk); |
| struct flowi4 *fl4; |
| struct rtable *rt; |
| |
| fl4 = &newinet->cork.fl.u.ip4; |
| |
| rcu_read_lock(); |
| opt = rcu_dereference(newinet->inet_opt); |
| flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark, |
| RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE, |
| sk->sk_protocol, inet_sk_flowi_flags(sk), |
| (opt && opt->opt.srr) ? opt->opt.faddr : ireq->rmt_addr, |
| ireq->loc_addr, ireq->rmt_port, inet_sk(sk)->inet_sport); |
| security_req_classify_flow(req, flowi4_to_flowi(fl4)); |
| rt = ip_route_output_flow(net, fl4, sk); |
| if (IS_ERR(rt)) |
| goto no_route; |
| if (opt && opt->opt.is_strictroute && rt->rt_uses_gateway) |
| goto route_err; |
| rcu_read_unlock(); |
| return &rt->dst; |
| |
| route_err: |
| ip_rt_put(rt); |
| no_route: |
| rcu_read_unlock(); |
| IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); |
| return NULL; |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_route_child_sock); |
| |
| static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport, |
| const u32 rnd, const u32 synq_hsize) |
| { |
| return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1); |
| } |
| |
| #if IS_ENABLED(CONFIG_IPV6) |
| #define AF_INET_FAMILY(fam) ((fam) == AF_INET) |
| #else |
| #define AF_INET_FAMILY(fam) 1 |
| #endif |
| |
| struct request_sock *inet_csk_search_req(const struct sock *sk, |
| struct request_sock ***prevp, |
| const __be16 rport, const __be32 raddr, |
| const __be32 laddr) |
| { |
| const struct inet_connection_sock *icsk = inet_csk(sk); |
| struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; |
| struct request_sock *req, **prev; |
| |
| for (prev = &lopt->syn_table[inet_synq_hash(raddr, rport, lopt->hash_rnd, |
| lopt->nr_table_entries)]; |
| (req = *prev) != NULL; |
| prev = &req->dl_next) { |
| const struct inet_request_sock *ireq = inet_rsk(req); |
| |
| if (ireq->rmt_port == rport && |
| ireq->rmt_addr == raddr && |
| ireq->loc_addr == laddr && |
| AF_INET_FAMILY(req->rsk_ops->family)) { |
| WARN_ON(req->sk); |
| *prevp = prev; |
| break; |
| } |
| } |
| |
| return req; |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_search_req); |
| |
| void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req, |
| unsigned long timeout) |
| { |
| struct inet_connection_sock *icsk = inet_csk(sk); |
| struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; |
| const u32 h = inet_synq_hash(inet_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port, |
| lopt->hash_rnd, lopt->nr_table_entries); |
| |
| reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout); |
| inet_csk_reqsk_queue_added(sk, timeout); |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add); |
| |
| /* Only thing we need from tcp.h */ |
| extern int sysctl_tcp_synack_retries; |
| |
| |
| /* Decide when to expire the request and when to resend SYN-ACK */ |
| static inline void syn_ack_recalc(struct request_sock *req, const int thresh, |
| const int max_retries, |
| const u8 rskq_defer_accept, |
| int *expire, int *resend) |
| { |
| if (!rskq_defer_accept) { |
| *expire = req->num_timeout >= thresh; |
| *resend = 1; |
| return; |
| } |
| *expire = req->num_timeout >= thresh && |
| (!inet_rsk(req)->acked || req->num_timeout >= max_retries); |
| /* |
| * Do not resend while waiting for data after ACK, |
| * start to resend on end of deferring period to give |
| * last chance for data or ACK to create established socket. |
| */ |
| *resend = !inet_rsk(req)->acked || |
| req->num_timeout >= rskq_defer_accept - 1; |
| } |
| |
| int inet_rtx_syn_ack(struct sock *parent, struct request_sock *req) |
| { |
| int err = req->rsk_ops->rtx_syn_ack(parent, req, NULL); |
| |
| if (!err) |
| req->num_retrans++; |
| return err; |
| } |
| EXPORT_SYMBOL(inet_rtx_syn_ack); |
| |
| void inet_csk_reqsk_queue_prune(struct sock *parent, |
| const unsigned long interval, |
| const unsigned long timeout, |
| const unsigned long max_rto) |
| { |
| struct inet_connection_sock *icsk = inet_csk(parent); |
| struct request_sock_queue *queue = &icsk->icsk_accept_queue; |
| struct listen_sock *lopt = queue->listen_opt; |
| int max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries; |
| int thresh = max_retries; |
| unsigned long now = jiffies; |
| struct request_sock **reqp, *req; |
| int i, budget; |
| |
| if (lopt == NULL || lopt->qlen == 0) |
| return; |
| |
| /* Normally all the openreqs are young and become mature |
| * (i.e. converted to established socket) for first timeout. |
| * If synack was not acknowledged for 1 second, it means |
| * one of the following things: synack was lost, ack was lost, |
| * rtt is high or nobody planned to ack (i.e. synflood). |
| * When server is a bit loaded, queue is populated with old |
| * open requests, reducing effective size of queue. |
| * When server is well loaded, queue size reduces to zero |
| * after several minutes of work. It is not synflood, |
| * it is normal operation. The solution is pruning |
| * too old entries overriding normal timeout, when |
| * situation becomes dangerous. |
| * |
| * Essentially, we reserve half of room for young |
| * embrions; and abort old ones without pity, if old |
| * ones are about to clog our table. |
| */ |
| if (lopt->qlen>>(lopt->max_qlen_log-1)) { |
| int young = (lopt->qlen_young<<1); |
| |
| while (thresh > 2) { |
| if (lopt->qlen < young) |
| break; |
| thresh--; |
| young <<= 1; |
| } |
| } |
| |
| if (queue->rskq_defer_accept) |
| max_retries = queue->rskq_defer_accept; |
| |
| budget = 2 * (lopt->nr_table_entries / (timeout / interval)); |
| i = lopt->clock_hand; |
| |
| do { |
| reqp=&lopt->syn_table[i]; |
| while ((req = *reqp) != NULL) { |
| if (time_after_eq(now, req->expires)) { |
| int expire = 0, resend = 0; |
| |
| syn_ack_recalc(req, thresh, max_retries, |
| queue->rskq_defer_accept, |
| &expire, &resend); |
| req->rsk_ops->syn_ack_timeout(parent, req); |
| if (!expire && |
| (!resend || |
| !inet_rtx_syn_ack(parent, req) || |
| inet_rsk(req)->acked)) { |
| unsigned long timeo; |
| |
| if (req->num_timeout++ == 0) |
| lopt->qlen_young--; |
| timeo = min(timeout << req->num_timeout, |
| max_rto); |
| req->expires = now + timeo; |
| reqp = &req->dl_next; |
| continue; |
| } |
| |
| /* Drop this request */ |
| inet_csk_reqsk_queue_unlink(parent, req, reqp); |
| reqsk_queue_removed(queue, req); |
| reqsk_free(req); |
| continue; |
| } |
| reqp = &req->dl_next; |
| } |
| |
| i = (i + 1) & (lopt->nr_table_entries - 1); |
| |
| } while (--budget > 0); |
| |
| lopt->clock_hand = i; |
| |
| if (lopt->qlen) |
| inet_csk_reset_keepalive_timer(parent, interval); |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune); |
| |
| /** |
| * inet_csk_clone_lock - clone an inet socket, and lock its clone |
| * @sk: the socket to clone |
| * @req: request_sock |
| * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) |
| * |
| * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) |
| */ |
| struct sock *inet_csk_clone_lock(const struct sock *sk, |
| const struct request_sock *req, |
| const gfp_t priority) |
| { |
| struct sock *newsk = sk_clone_lock(sk, priority); |
| |
| if (newsk != NULL) { |
| struct inet_connection_sock *newicsk = inet_csk(newsk); |
| |
| newsk->sk_state = TCP_SYN_RECV; |
| newicsk->icsk_bind_hash = NULL; |
| |
| inet_sk(newsk)->inet_dport = inet_rsk(req)->rmt_port; |
| inet_sk(newsk)->inet_num = ntohs(inet_rsk(req)->loc_port); |
| inet_sk(newsk)->inet_sport = inet_rsk(req)->loc_port; |
| newsk->sk_write_space = sk_stream_write_space; |
| |
| newicsk->icsk_retransmits = 0; |
| newicsk->icsk_backoff = 0; |
| newicsk->icsk_probes_out = 0; |
| |
| /* Deinitialize accept_queue to trap illegal accesses. */ |
| memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue)); |
| |
| security_inet_csk_clone(newsk, req); |
| } |
| return newsk; |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_clone_lock); |
| |
| /* |
| * At this point, there should be no process reference to this |
| * socket, and thus no user references at all. Therefore we |
| * can assume the socket waitqueue is inactive and nobody will |
| * try to jump onto it. |
| */ |
| void inet_csk_destroy_sock(struct sock *sk) |
| { |
| WARN_ON(sk->sk_state != TCP_CLOSE); |
| WARN_ON(!sock_flag(sk, SOCK_DEAD)); |
| |
| /* It cannot be in hash table! */ |
| WARN_ON(!sk_unhashed(sk)); |
| |
| /* If it has not 0 inet_sk(sk)->inet_num, it must be bound */ |
| WARN_ON(inet_sk(sk)->inet_num && !inet_csk(sk)->icsk_bind_hash); |
| |
| sk->sk_prot->destroy(sk); |
| |
| sk_stream_kill_queues(sk); |
| |
| xfrm_sk_free_policy(sk); |
| |
| sk_refcnt_debug_release(sk); |
| |
| percpu_counter_dec(sk->sk_prot->orphan_count); |
| sock_put(sk); |
| } |
| EXPORT_SYMBOL(inet_csk_destroy_sock); |
| |
| /* This function allows to force a closure of a socket after the call to |
| * tcp/dccp_create_openreq_child(). |
| */ |
| void inet_csk_prepare_forced_close(struct sock *sk) |
| __releases(&sk->sk_lock.slock) |
| { |
| /* sk_clone_lock locked the socket and set refcnt to 2 */ |
| bh_unlock_sock(sk); |
| sock_put(sk); |
| |
| /* The below has to be done to allow calling inet_csk_destroy_sock */ |
| sock_set_flag(sk, SOCK_DEAD); |
| percpu_counter_inc(sk->sk_prot->orphan_count); |
| inet_sk(sk)->inet_num = 0; |
| } |
| EXPORT_SYMBOL(inet_csk_prepare_forced_close); |
| |
| int inet_csk_listen_start(struct sock *sk, const int nr_table_entries) |
| { |
| struct inet_sock *inet = inet_sk(sk); |
| struct inet_connection_sock *icsk = inet_csk(sk); |
| int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries); |
| |
| if (rc != 0) |
| return rc; |
| |
| sk->sk_max_ack_backlog = 0; |
| sk->sk_ack_backlog = 0; |
| inet_csk_delack_init(sk); |
| |
| /* 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->inet_num)) { |
| inet->inet_sport = htons(inet->inet_num); |
| |
| sk_dst_reset(sk); |
| sk->sk_prot->hash(sk); |
| |
| return 0; |
| } |
| |
| sk->sk_state = TCP_CLOSE; |
| __reqsk_queue_destroy(&icsk->icsk_accept_queue); |
| return -EADDRINUSE; |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_listen_start); |
| |
| /* |
| * This routine closes sockets which have been at least partially |
| * opened, but not yet accepted. |
| */ |
| void inet_csk_listen_stop(struct sock *sk) |
| { |
| struct inet_connection_sock *icsk = inet_csk(sk); |
| struct request_sock_queue *queue = &icsk->icsk_accept_queue; |
| struct request_sock *acc_req; |
| struct request_sock *req; |
| |
| inet_csk_delete_keepalive_timer(sk); |
| |
| /* make all the listen_opt local to us */ |
| acc_req = reqsk_queue_yank_acceptq(queue); |
| |
| /* 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 |
| */ |
| reqsk_queue_destroy(queue); |
| |
| while ((req = acc_req) != NULL) { |
| struct sock *child = req->sk; |
| |
| acc_req = req->dl_next; |
| |
| local_bh_disable(); |
| bh_lock_sock(child); |
| WARN_ON(sock_owned_by_user(child)); |
| sock_hold(child); |
| |
| sk->sk_prot->disconnect(child, O_NONBLOCK); |
| |
| sock_orphan(child); |
| |
| percpu_counter_inc(sk->sk_prot->orphan_count); |
| |
| if (sk->sk_protocol == IPPROTO_TCP && tcp_rsk(req)->listener) { |
| BUG_ON(tcp_sk(child)->fastopen_rsk != req); |
| BUG_ON(sk != tcp_rsk(req)->listener); |
| |
| /* Paranoid, to prevent race condition if |
| * an inbound pkt destined for child is |
| * blocked by sock lock in tcp_v4_rcv(). |
| * Also to satisfy an assertion in |
| * tcp_v4_destroy_sock(). |
| */ |
| tcp_sk(child)->fastopen_rsk = NULL; |
| sock_put(sk); |
| } |
| inet_csk_destroy_sock(child); |
| |
| bh_unlock_sock(child); |
| local_bh_enable(); |
| sock_put(child); |
| |
| sk_acceptq_removed(sk); |
| __reqsk_free(req); |
| } |
| if (queue->fastopenq != NULL) { |
| /* Free all the reqs queued in rskq_rst_head. */ |
| spin_lock_bh(&queue->fastopenq->lock); |
| acc_req = queue->fastopenq->rskq_rst_head; |
| queue->fastopenq->rskq_rst_head = NULL; |
| spin_unlock_bh(&queue->fastopenq->lock); |
| while ((req = acc_req) != NULL) { |
| acc_req = req->dl_next; |
| __reqsk_free(req); |
| } |
| } |
| WARN_ON(sk->sk_ack_backlog); |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_listen_stop); |
| |
| void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr) |
| { |
| struct sockaddr_in *sin = (struct sockaddr_in *)uaddr; |
| const struct inet_sock *inet = inet_sk(sk); |
| |
| sin->sin_family = AF_INET; |
| sin->sin_addr.s_addr = inet->inet_daddr; |
| sin->sin_port = inet->inet_dport; |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr); |
| |
| #ifdef CONFIG_COMPAT |
| int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname, |
| char __user *optval, int __user *optlen) |
| { |
| const struct inet_connection_sock *icsk = inet_csk(sk); |
| |
| if (icsk->icsk_af_ops->compat_getsockopt != NULL) |
| return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname, |
| optval, optlen); |
| return icsk->icsk_af_ops->getsockopt(sk, level, optname, |
| optval, optlen); |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt); |
| |
| int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, |
| char __user *optval, unsigned int optlen) |
| { |
| const struct inet_connection_sock *icsk = inet_csk(sk); |
| |
| if (icsk->icsk_af_ops->compat_setsockopt != NULL) |
| return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname, |
| optval, optlen); |
| return icsk->icsk_af_ops->setsockopt(sk, level, optname, |
| optval, optlen); |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt); |
| #endif |
| |
| static struct dst_entry *inet_csk_rebuild_route(struct sock *sk, struct flowi *fl) |
| { |
| const struct inet_sock *inet = inet_sk(sk); |
| const struct ip_options_rcu *inet_opt; |
| __be32 daddr = inet->inet_daddr; |
| struct flowi4 *fl4; |
| struct rtable *rt; |
| |
| rcu_read_lock(); |
| inet_opt = rcu_dereference(inet->inet_opt); |
| if (inet_opt && inet_opt->opt.srr) |
| daddr = inet_opt->opt.faddr; |
| fl4 = &fl->u.ip4; |
| rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, |
| inet->inet_saddr, inet->inet_dport, |
| inet->inet_sport, sk->sk_protocol, |
| RT_CONN_FLAGS(sk), sk->sk_bound_dev_if); |
| if (IS_ERR(rt)) |
| rt = NULL; |
| if (rt) |
| sk_setup_caps(sk, &rt->dst); |
| rcu_read_unlock(); |
| |
| return &rt->dst; |
| } |
| |
| struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu) |
| { |
| struct dst_entry *dst = __sk_dst_check(sk, 0); |
| struct inet_sock *inet = inet_sk(sk); |
| |
| if (!dst) { |
| dst = inet_csk_rebuild_route(sk, &inet->cork.fl); |
| if (!dst) |
| goto out; |
| } |
| dst->ops->update_pmtu(dst, sk, NULL, mtu); |
| |
| dst = __sk_dst_check(sk, 0); |
| if (!dst) |
| dst = inet_csk_rebuild_route(sk, &inet->cork.fl); |
| out: |
| return dst; |
| } |
| EXPORT_SYMBOL_GPL(inet_csk_update_pmtu); |