diff options
author | Arnaldo Carvalho de Melo <acme@ghostprotocols.net> | 2005-08-10 03:11:08 (GMT) |
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committer | David S. Miller <davem@sunset.davemloft.net> | 2005-08-29 22:49:14 (GMT) |
commit | 3f421baa4720b708022f8bcc52a61e5cd6f10bf8 (patch) | |
tree | e4201b1e2356cea8b7bd8d68dfba06e84002a77d /net/ipv4/inet_connection_sock.c | |
parent | 463c84b97f24010a67cd871746d6a7e4c925a5f9 (diff) | |
download | linux-fsl-qoriq-3f421baa4720b708022f8bcc52a61e5cd6f10bf8.tar.xz |
[NET]: Just move the inet_connection_sock function from tcp sources
Completing the previous changeset, this also generalises tcp_v4_synq_add,
renaming it to inet_csk_reqsk_queue_hash_add, already geing used in the
DCCP tree, which I plan to merge RSN.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/inet_connection_sock.c')
-rw-r--r-- | net/ipv4/inet_connection_sock.c | 401 |
1 files changed, 401 insertions, 0 deletions
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c new file mode 100644 index 0000000..2712400 --- /dev/null +++ b/net/ipv4/inet_connection_sock.c @@ -0,0 +1,401 @@ +/* + * 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/config.h> +#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> + +#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 array holds the first and last local port number. + * For high-usage systems, use sysctl to change this to + * 32768-61000 + */ +int sysctl_local_port_range[2] = { 1024, 4999 }; + +static inline int inet_csk_bind_conflict(struct sock *sk, struct inet_bind_bucket *tb) +{ + const u32 sk_rcv_saddr = inet_rcv_saddr(sk); + struct sock *sk2; + struct hlist_node *node; + int reuse = sk->sk_reuse; + + sk_for_each_bound(sk2, node, &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) { + const u32 sk2_rcv_saddr = inet_rcv_saddr(sk2); + if (!sk2_rcv_saddr || !sk_rcv_saddr || + sk2_rcv_saddr == sk_rcv_saddr) + break; + } + } + } + return node != NULL; +} + +/* 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 inet_hashinfo *hashinfo, + struct sock *sk, unsigned short snum) +{ + struct inet_bind_hashbucket *head; + struct hlist_node *node; + struct inet_bind_bucket *tb; + int ret; + + local_bh_disable(); + if (!snum) { + int low = sysctl_local_port_range[0]; + int high = sysctl_local_port_range[1]; + int remaining = (high - low) + 1; + int rover; + + spin_lock(&hashinfo->portalloc_lock); + if (hashinfo->port_rover < low) + rover = low; + else + rover = hashinfo->port_rover; + do { + rover++; + if (rover > high) + rover = low; + head = &hashinfo->bhash[inet_bhashfn(rover, hashinfo->bhash_size)]; + spin_lock(&head->lock); + inet_bind_bucket_for_each(tb, node, &head->chain) + if (tb->port == rover) + goto next; + break; + next: + spin_unlock(&head->lock); + } while (--remaining > 0); + hashinfo->port_rover = rover; + spin_unlock(&hashinfo->portalloc_lock); + + /* 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) + goto fail; + + /* OK, here is the one we will use. HEAD is + * non-NULL and we hold it's mutex. + */ + snum = rover; + } else { + head = &hashinfo->bhash[inet_bhashfn(snum, hashinfo->bhash_size)]; + spin_lock(&head->lock); + inet_bind_bucket_for_each(tb, node, &head->chain) + if (tb->port == snum) + goto tb_found; + } + tb = NULL; + goto tb_not_found; +tb_found: + if (!hlist_empty(&tb->owners)) { + if (sk->sk_reuse > 1) + goto success; + if (tb->fastreuse > 0 && + sk->sk_reuse && sk->sk_state != TCP_LISTEN) { + goto success; + } else { + ret = 1; + if (inet_csk_bind_conflict(sk, tb)) + goto fail_unlock; + } + } +tb_not_found: + ret = 1; + if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep, 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; + } else if (tb->fastreuse && + (!sk->sk_reuse || sk->sk_state == TCP_LISTEN)) + tb->fastreuse = 0; +success: + if (!inet_csk(sk)->icsk_bind_hash) + inet_bind_hash(sk, tb, snum); + BUG_TRAP(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->sk_sleep, &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->sk_sleep, &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 sock *newsk; + 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(&icsk->icsk_accept_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; + } + + newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk); + BUG_TRAP(newsk->sk_state != TCP_SYN_RECV); +out: + release_sock(sk); + return newsk; +out_err: + newsk = 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); + + init_timer(&icsk->icsk_retransmit_timer); + init_timer(&icsk->icsk_delack_timer); + init_timer(&sk->sk_timer); + + icsk->icsk_retransmit_timer.function = retransmit_handler; + icsk->icsk_delack_timer.function = delack_handler; + sk->sk_timer.function = keepalive_handler; + + icsk->icsk_retransmit_timer.data = + icsk->icsk_delack_timer.data = + sk->sk_timer.data = (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, + const struct request_sock *req) +{ + struct rtable *rt; + const struct inet_request_sock *ireq = inet_rsk(req); + struct ip_options *opt = inet_rsk(req)->opt; + struct flowi fl = { .oif = sk->sk_bound_dev_if, + .nl_u = { .ip4_u = + { .daddr = ((opt && opt->srr) ? + opt->faddr : + ireq->rmt_addr), + .saddr = ireq->loc_addr, + .tos = RT_CONN_FLAGS(sk) } }, + .proto = sk->sk_protocol, + .uli_u = { .ports = + { .sport = inet_sk(sk)->sport, + .dport = ireq->rmt_port } } }; + + if (ip_route_output_flow(&rt, &fl, sk, 0)) { + IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES); + return NULL; + } + if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway) { + ip_rt_put(rt); + IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES); + return NULL; + } + return &rt->u.dst; +} + +EXPORT_SYMBOL_GPL(inet_csk_route_req); + +static inline u32 inet_synq_hash(const u32 raddr, const u16 rport, + const u32 rnd, const u16 synq_hsize) +{ + return jhash_2words(raddr, (u32)rport, rnd) & (synq_hsize - 1); +} + +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) +#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 __u16 rport, const __u32 raddr, + const __u32 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)) { + BUG_TRAP(!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, + const unsigned 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); |