*
* Implementation of the Transmission Control Protocol(TCP).
*
- * Version: $Id: tcp_minisocks.c,v 1.15 2002/02/01 22:01:04 davem Exp $
- *
* Authors: Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Mark Evans, <evansmp@uhura.aston.ac.uk>
* Jorge Cwik, <jorge@laser.satlink.net>
*/
-#include <linux/config.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/sysctl.h>
#include <net/inet_common.h>
#include <net/xfrm.h>
-#ifdef CONFIG_SYSCTL
-#define SYNC_INIT 0 /* let the user enable it */
-#else
-#define SYNC_INIT 1
-#endif
+int sysctl_tcp_syncookies __read_mostly = 1;
+EXPORT_SYMBOL(sysctl_tcp_syncookies);
-int sysctl_tcp_tw_recycle;
-int sysctl_tcp_max_tw_buckets = NR_FILE*2;
+int sysctl_tcp_abort_on_overflow __read_mostly;
+
+struct inet_timewait_death_row tcp_death_row = {
+ .sysctl_max_tw_buckets = NR_FILE * 2,
+ .period = TCP_TIMEWAIT_LEN / INET_TWDR_TWKILL_SLOTS,
+ .death_lock = __SPIN_LOCK_UNLOCKED(tcp_death_row.death_lock),
+ .hashinfo = &tcp_hashinfo,
+ .tw_timer = TIMER_INITIALIZER(inet_twdr_hangman, 0,
+ (unsigned long)&tcp_death_row),
+ .twkill_work = __WORK_INITIALIZER(tcp_death_row.twkill_work,
+ inet_twdr_twkill_work),
+/* Short-time timewait calendar */
-int sysctl_tcp_syncookies = SYNC_INIT;
-int sysctl_tcp_abort_on_overflow;
+ .twcal_hand = -1,
+ .twcal_timer = TIMER_INITIALIZER(inet_twdr_twcal_tick, 0,
+ (unsigned long)&tcp_death_row),
+};
-static void tcp_tw_schedule(struct inet_timewait_sock *tw, int timeo);
+EXPORT_SYMBOL_GPL(tcp_death_row);
static __inline__ int tcp_in_window(u32 seq, u32 end_seq, u32 s_win, u32 e_win)
{
return (seq == e_win && seq == end_seq);
}
-/* New-style handling of TIME_WAIT sockets. */
-
-int tcp_tw_count;
-
-/*
+/*
* * Main purpose of TIME-WAIT state is to close connection gracefully,
* when one of ends sits in LAST-ACK or CLOSING retransmitting FIN
* (and, probably, tail of data) and one or more our ACKs are lost.
tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb,
const struct tcphdr *th)
{
- struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);
struct tcp_options_received tmp_opt;
+ u8 *hash_location;
+ struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);
int paws_reject = 0;
tmp_opt.saw_tstamp = 0;
if (th->doff > (sizeof(*th) >> 2) && tcptw->tw_ts_recent_stamp) {
- tcp_parse_options(skb, &tmp_opt, 0);
+ tcp_parse_options(skb, &tmp_opt, &hash_location, 0);
if (tmp_opt.saw_tstamp) {
tmp_opt.ts_recent = tcptw->tw_ts_recent;
tmp_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp;
- paws_reject = tcp_paws_check(&tmp_opt, th->rst);
+ paws_reject = tcp_paws_reject(&tmp_opt, th->rst);
}
}
goto kill_with_rst;
/* Dup ACK? */
- if (!after(TCP_SKB_CB(skb)->end_seq, tcptw->tw_rcv_nxt) ||
+ if (!th->ack ||
+ !after(TCP_SKB_CB(skb)->end_seq, tcptw->tw_rcv_nxt) ||
TCP_SKB_CB(skb)->end_seq == TCP_SKB_CB(skb)->seq) {
inet_twsk_put(tw);
return TCP_TW_SUCCESS;
if (!th->fin ||
TCP_SKB_CB(skb)->end_seq != tcptw->tw_rcv_nxt + 1) {
kill_with_rst:
- tcp_tw_deschedule(tw);
+ inet_twsk_deschedule(tw, &tcp_death_row);
inet_twsk_put(tw);
return TCP_TW_RST;
}
tw->tw_substate = TCP_TIME_WAIT;
tcptw->tw_rcv_nxt = TCP_SKB_CB(skb)->end_seq;
if (tmp_opt.saw_tstamp) {
- tcptw->tw_ts_recent_stamp = xtime.tv_sec;
+ tcptw->tw_ts_recent_stamp = get_seconds();
tcptw->tw_ts_recent = tmp_opt.rcv_tsval;
}
/* I am shamed, but failed to make it more elegant.
* Yes, it is direct reference to IP, which is impossible
* to generalize to IPv6. Taking into account that IPv6
- * do not undertsnad recycling in any case, it not
+ * do not understand recycling in any case, it not
* a big problem in practice. --ANK */
if (tw->tw_family == AF_INET &&
- sysctl_tcp_tw_recycle && tcptw->tw_ts_recent_stamp &&
+ tcp_death_row.sysctl_tw_recycle && tcptw->tw_ts_recent_stamp &&
tcp_v4_tw_remember_stamp(tw))
- tcp_tw_schedule(tw, tw->tw_timeout);
+ inet_twsk_schedule(tw, &tcp_death_row, tw->tw_timeout,
+ TCP_TIMEWAIT_LEN);
else
- tcp_tw_schedule(tw, TCP_TIMEWAIT_LEN);
+ inet_twsk_schedule(tw, &tcp_death_row, TCP_TIMEWAIT_LEN,
+ TCP_TIMEWAIT_LEN);
return TCP_TW_ACK;
}
* "When a connection is [...] on TIME-WAIT state [...]
* [a TCP] MAY accept a new SYN from the remote TCP to
* reopen the connection directly, if it:
- *
+ *
* (1) assigns its initial sequence number for the new
* connection to be larger than the largest sequence
* number it used on the previous connection incarnation,
* and
*
- * (2) returns to TIME-WAIT state if the SYN turns out
+ * (2) returns to TIME-WAIT state if the SYN turns out
* to be an old duplicate".
*/
/* In window segment, it may be only reset or bare ack. */
if (th->rst) {
- /* This is TIME_WAIT assasination, in two flavors.
+ /* This is TIME_WAIT assassination, in two flavors.
* Oh well... nobody has a sufficient solution to this
* protocol bug yet.
*/
if (sysctl_tcp_rfc1337 == 0) {
kill:
- tcp_tw_deschedule(tw);
+ inet_twsk_deschedule(tw, &tcp_death_row);
inet_twsk_put(tw);
return TCP_TW_SUCCESS;
}
}
- tcp_tw_schedule(tw, TCP_TIMEWAIT_LEN);
+ inet_twsk_schedule(tw, &tcp_death_row, TCP_TIMEWAIT_LEN,
+ TCP_TIMEWAIT_LEN);
if (tmp_opt.saw_tstamp) {
tcptw->tw_ts_recent = tmp_opt.rcv_tsval;
- tcptw->tw_ts_recent_stamp = xtime.tv_sec;
+ tcptw->tw_ts_recent_stamp = get_seconds();
}
inet_twsk_put(tw);
}
if (paws_reject)
- NET_INC_STATS_BH(LINUX_MIB_PAWSESTABREJECTED);
+ NET_INC_STATS_BH(twsk_net(tw), LINUX_MIB_PAWSESTABREJECTED);
- if(!th->rst) {
+ if (!th->rst) {
/* In this case we must reset the TIMEWAIT timer.
*
* If it is ACKless SYN it may be both old duplicate
* Do not reschedule in the last case.
*/
if (paws_reject || th->ack)
- tcp_tw_schedule(tw, TCP_TIMEWAIT_LEN);
+ inet_twsk_schedule(tw, &tcp_death_row, TCP_TIMEWAIT_LEN,
+ TCP_TIMEWAIT_LEN);
/* Send ACK. Note, we do not put the bucket,
* it will be released by caller.
return TCP_TW_SUCCESS;
}
-/*
+/*
* Move a socket to time-wait or dead fin-wait-2 state.
- */
+ */
void tcp_time_wait(struct sock *sk, int state, int timeo)
{
struct inet_timewait_sock *tw = NULL;
+ const struct inet_connection_sock *icsk = inet_csk(sk);
const struct tcp_sock *tp = tcp_sk(sk);
int recycle_ok = 0;
- if (sysctl_tcp_tw_recycle && tp->rx_opt.ts_recent_stamp)
- recycle_ok = tp->af_specific->remember_stamp(sk);
+ if (tcp_death_row.sysctl_tw_recycle && tp->rx_opt.ts_recent_stamp)
+ recycle_ok = icsk->icsk_af_ops->remember_stamp(sk);
- if (tcp_tw_count < sysctl_tcp_max_tw_buckets)
+ if (tcp_death_row.tw_count < tcp_death_row.sysctl_max_tw_buckets)
tw = inet_twsk_alloc(sk, state);
if (tw != NULL) {
struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);
- const int rto = (tp->rto << 2) - (tp->rto >> 1);
+ const int rto = (icsk->icsk_rto << 2) - (icsk->icsk_rto >> 1);
tw->tw_rcv_wscale = tp->rx_opt.rcv_wscale;
tcptw->tw_rcv_nxt = tp->rcv_nxt;
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
if (tw->tw_family == PF_INET6) {
struct ipv6_pinfo *np = inet6_sk(sk);
- struct tcp6_timewait_sock *tcp6tw = tcp6_twsk((struct sock *)tw);
+ struct inet6_timewait_sock *tw6;
- ipv6_addr_copy(&tcp6tw->tw_v6_daddr, &np->daddr);
- ipv6_addr_copy(&tcp6tw->tw_v6_rcv_saddr, &np->rcv_saddr);
+ tw->tw_ipv6_offset = inet6_tw_offset(sk->sk_prot);
+ tw6 = inet6_twsk((struct sock *)tw);
+ ipv6_addr_copy(&tw6->tw_v6_daddr, &np->daddr);
+ ipv6_addr_copy(&tw6->tw_v6_rcv_saddr, &np->rcv_saddr);
tw->tw_ipv6only = np->ipv6only;
}
#endif
+
+#ifdef CONFIG_TCP_MD5SIG
+ /*
+ * The timewait bucket does not have the key DB from the
+ * sock structure. We just make a quick copy of the
+ * md5 key being used (if indeed we are using one)
+ * so the timewait ack generating code has the key.
+ */
+ do {
+ struct tcp_md5sig_key *key;
+ memset(tcptw->tw_md5_key, 0, sizeof(tcptw->tw_md5_key));
+ tcptw->tw_md5_keylen = 0;
+ key = tp->af_specific->md5_lookup(sk, sk);
+ if (key != NULL) {
+ memcpy(&tcptw->tw_md5_key, key->key, key->keylen);
+ tcptw->tw_md5_keylen = key->keylen;
+ if (tcp_alloc_md5sig_pool(sk) == NULL)
+ BUG();
+ }
+ } while (0);
+#endif
+
/* Linkage updates. */
__inet_twsk_hashdance(tw, sk, &tcp_hashinfo);
timeo = TCP_TIMEWAIT_LEN;
}
- tcp_tw_schedule(tw, timeo);
+ inet_twsk_schedule(tw, &tcp_death_row, timeo,
+ TCP_TIMEWAIT_LEN);
inet_twsk_put(tw);
} else {
/* Sorry, if we're out of memory, just CLOSE this
* socket up. We've got bigger problems than
* non-graceful socket closings.
*/
- if (net_ratelimit())
- printk(KERN_INFO "TCP: time wait bucket table overflow\n");
+ LIMIT_NETDEBUG(KERN_INFO "TCP: time wait bucket table overflow\n");
}
tcp_update_metrics(sk);
tcp_done(sk);
}
-/* Kill off TIME_WAIT sockets once their lifetime has expired. */
-static int tcp_tw_death_row_slot;
-
-static void tcp_twkill(unsigned long);
-
-/* TIME_WAIT reaping mechanism. */
-#define TCP_TWKILL_SLOTS 8 /* Please keep this a power of 2. */
-#define TCP_TWKILL_PERIOD (TCP_TIMEWAIT_LEN/TCP_TWKILL_SLOTS)
-
-#define TCP_TWKILL_QUOTA 100
-
-static struct hlist_head tcp_tw_death_row[TCP_TWKILL_SLOTS];
-static DEFINE_SPINLOCK(tw_death_lock);
-static struct timer_list tcp_tw_timer = TIMER_INITIALIZER(tcp_twkill, 0, 0);
-static void twkill_work(void *);
-static DECLARE_WORK(tcp_twkill_work, twkill_work, NULL);
-static u32 twkill_thread_slots;
-
-/* Returns non-zero if quota exceeded. */
-static int tcp_do_twkill_work(int slot, unsigned int quota)
+void tcp_twsk_destructor(struct sock *sk)
{
- struct inet_timewait_sock *tw;
- struct hlist_node *node;
- unsigned int killed;
- int ret;
-
- /* NOTE: compare this to previous version where lock
- * was released after detaching chain. It was racy,
- * because tw buckets are scheduled in not serialized context
- * in 2.3 (with netfilter), and with softnet it is common, because
- * soft irqs are not sequenced.
- */
- killed = 0;
- ret = 0;
-rescan:
- inet_twsk_for_each_inmate(tw, node, &tcp_tw_death_row[slot]) {
- __inet_twsk_del_dead_node(tw);
- spin_unlock(&tw_death_lock);
- __inet_twsk_kill(tw, &tcp_hashinfo);
- inet_twsk_put(tw);
- killed++;
- spin_lock(&tw_death_lock);
- if (killed > quota) {
- ret = 1;
- break;
- }
-
- /* While we dropped tw_death_lock, another cpu may have
- * killed off the next TW bucket in the list, therefore
- * do a fresh re-read of the hlist head node with the
- * lock reacquired. We still use the hlist traversal
- * macro in order to get the prefetches.
- */
- goto rescan;
- }
-
- tcp_tw_count -= killed;
- NET_ADD_STATS_BH(LINUX_MIB_TIMEWAITED, killed);
-
- return ret;
-}
-
-static void tcp_twkill(unsigned long dummy)
-{
- int need_timer, ret;
-
- spin_lock(&tw_death_lock);
-
- if (tcp_tw_count == 0)
- goto out;
-
- need_timer = 0;
- ret = tcp_do_twkill_work(tcp_tw_death_row_slot, TCP_TWKILL_QUOTA);
- if (ret) {
- twkill_thread_slots |= (1 << tcp_tw_death_row_slot);
- mb();
- schedule_work(&tcp_twkill_work);
- need_timer = 1;
- } else {
- /* We purged the entire slot, anything left? */
- if (tcp_tw_count)
- need_timer = 1;
- }
- tcp_tw_death_row_slot =
- ((tcp_tw_death_row_slot + 1) & (TCP_TWKILL_SLOTS - 1));
- if (need_timer)
- mod_timer(&tcp_tw_timer, jiffies + TCP_TWKILL_PERIOD);
-out:
- spin_unlock(&tw_death_lock);
-}
-
-extern void twkill_slots_invalid(void);
-
-static void twkill_work(void *dummy)
-{
- int i;
-
- if ((TCP_TWKILL_SLOTS - 1) > (sizeof(twkill_thread_slots) * 8))
- twkill_slots_invalid();
-
- while (twkill_thread_slots) {
- spin_lock_bh(&tw_death_lock);
- for (i = 0; i < TCP_TWKILL_SLOTS; i++) {
- if (!(twkill_thread_slots & (1 << i)))
- continue;
-
- while (tcp_do_twkill_work(i, TCP_TWKILL_QUOTA) != 0) {
- if (need_resched()) {
- spin_unlock_bh(&tw_death_lock);
- schedule();
- spin_lock_bh(&tw_death_lock);
- }
- }
-
- twkill_thread_slots &= ~(1 << i);
- }
- spin_unlock_bh(&tw_death_lock);
- }
-}
-
-/* These are always called from BH context. See callers in
- * tcp_input.c to verify this.
- */
-
-/* This is for handling early-kills of TIME_WAIT sockets. */
-void tcp_tw_deschedule(struct inet_timewait_sock *tw)
-{
- spin_lock(&tw_death_lock);
- if (inet_twsk_del_dead_node(tw)) {
- inet_twsk_put(tw);
- if (--tcp_tw_count == 0)
- del_timer(&tcp_tw_timer);
- }
- spin_unlock(&tw_death_lock);
- __inet_twsk_kill(tw, &tcp_hashinfo);
+#ifdef CONFIG_TCP_MD5SIG
+ struct tcp_timewait_sock *twsk = tcp_twsk(sk);
+ if (twsk->tw_md5_keylen)
+ tcp_free_md5sig_pool();
+#endif
}
-/* Short-time timewait calendar */
-
-static int tcp_twcal_hand = -1;
-static int tcp_twcal_jiffie;
-static void tcp_twcal_tick(unsigned long);
-static struct timer_list tcp_twcal_timer =
- TIMER_INITIALIZER(tcp_twcal_tick, 0, 0);
-static struct hlist_head tcp_twcal_row[TCP_TW_RECYCLE_SLOTS];
-
-static void tcp_tw_schedule(struct inet_timewait_sock *tw, const int timeo)
-{
- struct hlist_head *list;
- int slot;
-
- /* timeout := RTO * 3.5
- *
- * 3.5 = 1+2+0.5 to wait for two retransmits.
- *
- * RATIONALE: if FIN arrived and we entered TIME-WAIT state,
- * our ACK acking that FIN can be lost. If N subsequent retransmitted
- * FINs (or previous seqments) are lost (probability of such event
- * is p^(N+1), where p is probability to lose single packet and
- * time to detect the loss is about RTO*(2^N - 1) with exponential
- * backoff). Normal timewait length is calculated so, that we
- * waited at least for one retransmitted FIN (maximal RTO is 120sec).
- * [ BTW Linux. following BSD, violates this requirement waiting
- * only for 60sec, we should wait at least for 240 secs.
- * Well, 240 consumes too much of resources 8)
- * ]
- * This interval is not reduced to catch old duplicate and
- * responces to our wandering segments living for two MSLs.
- * However, if we use PAWS to detect
- * old duplicates, we can reduce the interval to bounds required
- * by RTO, rather than MSL. So, if peer understands PAWS, we
- * kill tw bucket after 3.5*RTO (it is important that this number
- * is greater than TS tick!) and detect old duplicates with help
- * of PAWS.
- */
- slot = (timeo + (1<<TCP_TW_RECYCLE_TICK) - 1) >> TCP_TW_RECYCLE_TICK;
-
- spin_lock(&tw_death_lock);
-
- /* Unlink it, if it was scheduled */
- if (inet_twsk_del_dead_node(tw))
- tcp_tw_count--;
- else
- atomic_inc(&tw->tw_refcnt);
-
- if (slot >= TCP_TW_RECYCLE_SLOTS) {
- /* Schedule to slow timer */
- if (timeo >= TCP_TIMEWAIT_LEN) {
- slot = TCP_TWKILL_SLOTS-1;
- } else {
- slot = (timeo + TCP_TWKILL_PERIOD-1) / TCP_TWKILL_PERIOD;
- if (slot >= TCP_TWKILL_SLOTS)
- slot = TCP_TWKILL_SLOTS-1;
- }
- tw->tw_ttd = jiffies + timeo;
- slot = (tcp_tw_death_row_slot + slot) & (TCP_TWKILL_SLOTS - 1);
- list = &tcp_tw_death_row[slot];
- } else {
- tw->tw_ttd = jiffies + (slot << TCP_TW_RECYCLE_TICK);
-
- if (tcp_twcal_hand < 0) {
- tcp_twcal_hand = 0;
- tcp_twcal_jiffie = jiffies;
- tcp_twcal_timer.expires = tcp_twcal_jiffie + (slot<<TCP_TW_RECYCLE_TICK);
- add_timer(&tcp_twcal_timer);
- } else {
- if (time_after(tcp_twcal_timer.expires, jiffies + (slot<<TCP_TW_RECYCLE_TICK)))
- mod_timer(&tcp_twcal_timer, jiffies + (slot<<TCP_TW_RECYCLE_TICK));
- slot = (tcp_twcal_hand + slot)&(TCP_TW_RECYCLE_SLOTS-1);
- }
- list = &tcp_twcal_row[slot];
- }
-
- hlist_add_head(&tw->tw_death_node, list);
-
- if (tcp_tw_count++ == 0)
- mod_timer(&tcp_tw_timer, jiffies+TCP_TWKILL_PERIOD);
- spin_unlock(&tw_death_lock);
-}
+EXPORT_SYMBOL_GPL(tcp_twsk_destructor);
-void tcp_twcal_tick(unsigned long dummy)
+static inline void TCP_ECN_openreq_child(struct tcp_sock *tp,
+ struct request_sock *req)
{
- int n, slot;
- unsigned long j;
- unsigned long now = jiffies;
- int killed = 0;
- int adv = 0;
-
- spin_lock(&tw_death_lock);
- if (tcp_twcal_hand < 0)
- goto out;
-
- slot = tcp_twcal_hand;
- j = tcp_twcal_jiffie;
-
- for (n=0; n<TCP_TW_RECYCLE_SLOTS; n++) {
- if (time_before_eq(j, now)) {
- struct hlist_node *node, *safe;
- struct inet_timewait_sock *tw;
-
- inet_twsk_for_each_inmate_safe(tw, node, safe,
- &tcp_twcal_row[slot]) {
- __inet_twsk_del_dead_node(tw);
- __inet_twsk_kill(tw, &tcp_hashinfo);
- inet_twsk_put(tw);
- killed++;
- }
- } else {
- if (!adv) {
- adv = 1;
- tcp_twcal_jiffie = j;
- tcp_twcal_hand = slot;
- }
-
- if (!hlist_empty(&tcp_twcal_row[slot])) {
- mod_timer(&tcp_twcal_timer, j);
- goto out;
- }
- }
- j += (1<<TCP_TW_RECYCLE_TICK);
- slot = (slot+1)&(TCP_TW_RECYCLE_SLOTS-1);
- }
- tcp_twcal_hand = -1;
-
-out:
- if ((tcp_tw_count -= killed) == 0)
- del_timer(&tcp_tw_timer);
- NET_ADD_STATS_BH(LINUX_MIB_TIMEWAITKILLED, killed);
- spin_unlock(&tw_death_lock);
+ tp->ecn_flags = inet_rsk(req)->ecn_ok ? TCP_ECN_OK : 0;
}
/* This is not only more efficient than what we used to do, it eliminates
*/
struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, struct sk_buff *skb)
{
- /* allocate the newsk from the same slab of the master sock,
- * if not, at sk_free time we'll try to free it from the wrong
- * slabcache (i.e. is it TCPv4 or v6?), this is handled thru sk->sk_prot -acme */
- struct sock *newsk = sk_alloc(PF_INET, GFP_ATOMIC, sk->sk_prot, 0);
+ struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC);
- if(newsk != NULL) {
- struct inet_request_sock *ireq = inet_rsk(req);
+ if (newsk != NULL) {
+ const struct inet_request_sock *ireq = inet_rsk(req);
struct tcp_request_sock *treq = tcp_rsk(req);
- struct inet_sock *newinet = inet_sk(newsk);
- struct tcp_sock *newtp;
- struct sk_filter *filter;
-
- memcpy(newsk, sk, sizeof(struct tcp_sock));
- newsk->sk_state = TCP_SYN_RECV;
-
- /* SANITY */
- sk_node_init(&newsk->sk_node);
- newinet->bind_hash = NULL;
-
- /* Clone the TCP header template */
- newinet->dport = ireq->rmt_port;
-
- sock_lock_init(newsk);
- bh_lock_sock(newsk);
-
- rwlock_init(&newsk->sk_dst_lock);
- newsk->sk_dst_cache = NULL;
- atomic_set(&newsk->sk_rmem_alloc, 0);
- skb_queue_head_init(&newsk->sk_receive_queue);
- atomic_set(&newsk->sk_wmem_alloc, 0);
- skb_queue_head_init(&newsk->sk_write_queue);
- atomic_set(&newsk->sk_omem_alloc, 0);
- newsk->sk_wmem_queued = 0;
- newsk->sk_forward_alloc = 0;
-
- sock_reset_flag(newsk, SOCK_DONE);
- newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
- newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
- newsk->sk_send_head = NULL;
- rwlock_init(&newsk->sk_callback_lock);
- skb_queue_head_init(&newsk->sk_error_queue);
- newsk->sk_write_space = sk_stream_write_space;
-
- if ((filter = newsk->sk_filter) != NULL)
- sk_filter_charge(newsk, filter);
-
- if (unlikely(xfrm_sk_clone_policy(newsk))) {
- /* It is still raw copy of parent, so invalidate
- * destructor and make plain sk_free() */
- newsk->sk_destruct = NULL;
- sk_free(newsk);
- return NULL;
+ struct inet_connection_sock *newicsk = inet_csk(newsk);
+ struct tcp_sock *newtp = tcp_sk(newsk);
+ struct tcp_sock *oldtp = tcp_sk(sk);
+ struct tcp_cookie_values *oldcvp = oldtp->cookie_values;
+
+ /* TCP Cookie Transactions require space for the cookie pair,
+ * as it differs for each connection. There is no need to
+ * copy any s_data_payload stored at the original socket.
+ * Failure will prevent resuming the connection.
+ *
+ * Presumed copied, in order of appearance:
+ * cookie_in_always, cookie_out_never
+ */
+ if (oldcvp != NULL) {
+ struct tcp_cookie_values *newcvp =
+ kzalloc(sizeof(*newtp->cookie_values),
+ GFP_ATOMIC);
+
+ if (newcvp != NULL) {
+ kref_init(&newcvp->kref);
+ newcvp->cookie_desired =
+ oldcvp->cookie_desired;
+ newtp->cookie_values = newcvp;
+ } else {
+ /* Not Yet Implemented */
+ newtp->cookie_values = NULL;
+ }
}
/* Now setup tcp_sock */
- newtp = tcp_sk(newsk);
newtp->pred_flags = 0;
+
+ newtp->rcv_wup = newtp->copied_seq =
newtp->rcv_nxt = treq->rcv_isn + 1;
- newtp->snd_nxt = treq->snt_isn + 1;
- newtp->snd_una = treq->snt_isn + 1;
- newtp->snd_sml = treq->snt_isn + 1;
+
+ newtp->snd_sml = newtp->snd_una =
+ newtp->snd_nxt = newtp->snd_up =
+ treq->snt_isn + 1 + tcp_s_data_size(oldtp);
tcp_prequeue_init(newtp);
- tcp_init_wl(newtp, treq->snt_isn, treq->rcv_isn);
+ tcp_init_wl(newtp, treq->rcv_isn);
- newtp->retransmits = 0;
- newtp->backoff = 0;
newtp->srtt = 0;
newtp->mdev = TCP_TIMEOUT_INIT;
- newtp->rto = TCP_TIMEOUT_INIT;
+ newicsk->icsk_rto = TCP_TIMEOUT_INIT;
newtp->packets_out = 0;
- newtp->left_out = 0;
newtp->retrans_out = 0;
newtp->sacked_out = 0;
newtp->fackets_out = 0;
- newtp->snd_ssthresh = 0x7fffffff;
+ newtp->snd_ssthresh = TCP_INFINITE_SSTHRESH;
/* So many TCP implementations out there (incorrectly) count the
* initial SYN frame in their delayed-ACK and congestion control
*/
newtp->snd_cwnd = 2;
newtp->snd_cwnd_cnt = 0;
+ newtp->bytes_acked = 0;
newtp->frto_counter = 0;
newtp->frto_highmark = 0;
- newtp->ca_ops = &tcp_reno;
+ newicsk->icsk_ca_ops = &tcp_init_congestion_ops;
- tcp_set_ca_state(newtp, TCP_CA_Open);
+ tcp_set_ca_state(newsk, TCP_CA_Open);
tcp_init_xmit_timers(newsk);
skb_queue_head_init(&newtp->out_of_order_queue);
- newtp->rcv_wup = treq->rcv_isn + 1;
- newtp->write_seq = treq->snt_isn + 1;
- newtp->pushed_seq = newtp->write_seq;
- newtp->copied_seq = treq->rcv_isn + 1;
+ newtp->write_seq = newtp->pushed_seq =
+ treq->snt_isn + 1 + tcp_s_data_size(oldtp);
newtp->rx_opt.saw_tstamp = 0;
newtp->rx_opt.dsack = 0;
- newtp->rx_opt.eff_sacks = 0;
-
- newtp->probes_out = 0;
newtp->rx_opt.num_sacks = 0;
- newtp->urg_data = 0;
- /* Deinitialize accept_queue to trap illegal accesses. */
- memset(&newtp->accept_queue, 0, sizeof(newtp->accept_queue));
-
- /* Back to base struct sock members. */
- newsk->sk_err = 0;
- newsk->sk_priority = 0;
- atomic_set(&newsk->sk_refcnt, 2);
-
- /*
- * Increment the counter in the same struct proto as the master
- * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
- * is the same as sk->sk_prot->socks, as this field was copied
- * with memcpy), same rationale as the first comment in this
- * function.
- *
- * This _changes_ the previous behaviour, where
- * tcp_create_openreq_child always was incrementing the
- * equivalent to tcp_prot->socks (inet_sock_nr), so this have
- * to be taken into account in all callers. -acme
- */
- sk_refcnt_debug_inc(newsk);
- atomic_inc(&tcp_sockets_allocated);
+ newtp->urg_data = 0;
if (sock_flag(newsk, SOCK_KEEPOPEN))
- tcp_reset_keepalive_timer(newsk,
- keepalive_time_when(newtp));
- newsk->sk_socket = NULL;
- newsk->sk_sleep = NULL;
+ inet_csk_reset_keepalive_timer(newsk,
+ keepalive_time_when(newtp));
newtp->rx_opt.tstamp_ok = ireq->tstamp_ok;
- if((newtp->rx_opt.sack_ok = ireq->sack_ok) != 0) {
+ if ((newtp->rx_opt.sack_ok = ireq->sack_ok) != 0) {
if (sysctl_tcp_fack)
- newtp->rx_opt.sack_ok |= 2;
+ tcp_enable_fack(newtp);
}
newtp->window_clamp = req->window_clamp;
newtp->rcv_ssthresh = req->rcv_wnd;
newtp->rx_opt.snd_wscale = newtp->rx_opt.rcv_wscale = 0;
newtp->window_clamp = min(newtp->window_clamp, 65535U);
}
- newtp->snd_wnd = ntohs(skb->h.th->window) << newtp->rx_opt.snd_wscale;
+ newtp->snd_wnd = (ntohs(tcp_hdr(skb)->window) <<
+ newtp->rx_opt.snd_wscale);
newtp->max_window = newtp->snd_wnd;
if (newtp->rx_opt.tstamp_ok) {
newtp->rx_opt.ts_recent = req->ts_recent;
- newtp->rx_opt.ts_recent_stamp = xtime.tv_sec;
+ newtp->rx_opt.ts_recent_stamp = get_seconds();
newtp->tcp_header_len = sizeof(struct tcphdr) + TCPOLEN_TSTAMP_ALIGNED;
} else {
newtp->rx_opt.ts_recent_stamp = 0;
newtp->tcp_header_len = sizeof(struct tcphdr);
}
- if (skb->len >= TCP_MIN_RCVMSS+newtp->tcp_header_len)
- newtp->ack.last_seg_size = skb->len-newtp->tcp_header_len;
+#ifdef CONFIG_TCP_MD5SIG
+ newtp->md5sig_info = NULL; /*XXX*/
+ if (newtp->af_specific->md5_lookup(sk, newsk))
+ newtp->tcp_header_len += TCPOLEN_MD5SIG_ALIGNED;
+#endif
+ if (skb->len >= TCP_MSS_DEFAULT + newtp->tcp_header_len)
+ newicsk->icsk_ack.last_seg_size = skb->len - newtp->tcp_header_len;
newtp->rx_opt.mss_clamp = req->mss;
TCP_ECN_openreq_child(newtp, req);
- if (newtp->ecn_flags&TCP_ECN_OK)
- sock_set_flag(newsk, SOCK_NO_LARGESEND);
- TCP_INC_STATS_BH(TCP_MIB_PASSIVEOPENS);
+ TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_PASSIVEOPENS);
}
return newsk;
}
-/*
+/*
* Process an incoming packet for SYN_RECV sockets represented
* as a request_sock.
*/
-struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb,
+struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb,
struct request_sock *req,
struct request_sock **prev)
{
- struct tcphdr *th = skb->h.th;
- struct tcp_sock *tp = tcp_sk(sk);
- u32 flg = tcp_flag_word(th) & (TCP_FLAG_RST|TCP_FLAG_SYN|TCP_FLAG_ACK);
- int paws_reject = 0;
struct tcp_options_received tmp_opt;
+ u8 *hash_location;
struct sock *child;
+ const struct tcphdr *th = tcp_hdr(skb);
+ __be32 flg = tcp_flag_word(th) & (TCP_FLAG_RST|TCP_FLAG_SYN|TCP_FLAG_ACK);
+ int paws_reject = 0;
tmp_opt.saw_tstamp = 0;
if (th->doff > (sizeof(struct tcphdr)>>2)) {
- tcp_parse_options(skb, &tmp_opt, 0);
+ tcp_parse_options(skb, &tmp_opt, &hash_location, 0);
if (tmp_opt.saw_tstamp) {
tmp_opt.ts_recent = req->ts_recent;
* it can be estimated (approximately)
* from another data.
*/
- tmp_opt.ts_recent_stamp = xtime.tv_sec - ((TCP_TIMEOUT_INIT/HZ)<<req->retrans);
- paws_reject = tcp_paws_check(&tmp_opt, th->rst);
+ tmp_opt.ts_recent_stamp = get_seconds() - ((TCP_TIMEOUT_INIT/HZ)<<req->retrans);
+ paws_reject = tcp_paws_reject(&tmp_opt, th->rst);
}
}
does sequence test, SYN is truncated, and thus we consider
it a bare ACK.
- If tp->defer_accept, we silently drop this bare ACK. Otherwise,
- we create an established connection. Both ends (listening sockets)
- accept the new incoming connection and try to talk to each other. 8-)
+ If icsk->icsk_accept_queue.rskq_defer_accept, we silently drop this
+ bare ACK. Otherwise, we create an established connection. Both
+ ends (listening sockets) accept the new incoming connection and try
+ to talk to each other. 8-)
Note: This case is both harmless, and rare. Possibility is about the
same as us discovering intelligent life on another plant tomorrow.
/* RFC793 page 36: "If the connection is in any non-synchronized state ...
* and the incoming segment acknowledges something not yet
- * sent (the segment carries an unaccaptable ACK) ...
+ * sent (the segment carries an unacceptable ACK) ...
* a reset is sent."
*
* Invalid ACK: reset will be sent by listening socket
*/
if ((flg & TCP_FLAG_ACK) &&
- (TCP_SKB_CB(skb)->ack_seq != tcp_rsk(req)->snt_isn + 1))
+ (TCP_SKB_CB(skb)->ack_seq !=
+ tcp_rsk(req)->snt_isn + 1 + tcp_s_data_size(tcp_sk(sk))))
return sk;
/* Also, it would be not so bad idea to check rcv_tsecr, which
tcp_rsk(req)->rcv_isn + 1, tcp_rsk(req)->rcv_isn + 1 + req->rcv_wnd)) {
/* Out of window: send ACK and drop. */
if (!(flg & TCP_FLAG_RST))
- req->rsk_ops->send_ack(skb, req);
+ req->rsk_ops->send_ack(sk, skb, req);
if (paws_reject)
- NET_INC_STATS_BH(LINUX_MIB_PAWSESTABREJECTED);
+ NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_PAWSESTABREJECTED);
return NULL;
}
/* In sequence, PAWS is OK. */
if (tmp_opt.saw_tstamp && !after(TCP_SKB_CB(skb)->seq, tcp_rsk(req)->rcv_isn + 1))
- req->ts_recent = tmp_opt.rcv_tsval;
+ req->ts_recent = tmp_opt.rcv_tsval;
- if (TCP_SKB_CB(skb)->seq == tcp_rsk(req)->rcv_isn) {
- /* Truncate SYN, it is out of window starting
- at tcp_rsk(req)->rcv_isn + 1. */
- flg &= ~TCP_FLAG_SYN;
- }
+ if (TCP_SKB_CB(skb)->seq == tcp_rsk(req)->rcv_isn) {
+ /* Truncate SYN, it is out of window starting
+ at tcp_rsk(req)->rcv_isn + 1. */
+ flg &= ~TCP_FLAG_SYN;
+ }
- /* RFC793: "second check the RST bit" and
- * "fourth, check the SYN bit"
- */
- if (flg & (TCP_FLAG_RST|TCP_FLAG_SYN))
- goto embryonic_reset;
+ /* RFC793: "second check the RST bit" and
+ * "fourth, check the SYN bit"
+ */
+ if (flg & (TCP_FLAG_RST|TCP_FLAG_SYN)) {
+ TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_ATTEMPTFAILS);
+ goto embryonic_reset;
+ }
- /* ACK sequence verified above, just make sure ACK is
- * set. If ACK not set, just silently drop the packet.
- */
- if (!(flg & TCP_FLAG_ACK))
- return NULL;
+ /* ACK sequence verified above, just make sure ACK is
+ * set. If ACK not set, just silently drop the packet.
+ */
+ if (!(flg & TCP_FLAG_ACK))
+ return NULL;
- /* If TCP_DEFER_ACCEPT is set, drop bare ACK. */
- if (tp->defer_accept && TCP_SKB_CB(skb)->end_seq == tcp_rsk(req)->rcv_isn + 1) {
- inet_rsk(req)->acked = 1;
- return NULL;
- }
+ /* While TCP_DEFER_ACCEPT is active, drop bare ACK. */
+ if (req->retrans < inet_csk(sk)->icsk_accept_queue.rskq_defer_accept &&
+ TCP_SKB_CB(skb)->end_seq == tcp_rsk(req)->rcv_isn + 1) {
+ inet_rsk(req)->acked = 1;
+ return NULL;
+ }
- /* OK, ACK is valid, create big socket and
- * feed this segment to it. It will repeat all
- * the tests. THIS SEGMENT MUST MOVE SOCKET TO
- * ESTABLISHED STATE. If it will be dropped after
- * socket is created, wait for troubles.
- */
- child = tp->af_specific->syn_recv_sock(sk, skb, req, NULL);
- if (child == NULL)
- goto listen_overflow;
+ /* OK, ACK is valid, create big socket and
+ * feed this segment to it. It will repeat all
+ * the tests. THIS SEGMENT MUST MOVE SOCKET TO
+ * ESTABLISHED STATE. If it will be dropped after
+ * socket is created, wait for troubles.
+ */
+ child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL);
+ if (child == NULL)
+ goto listen_overflow;
- tcp_synq_unlink(tp, req, prev);
- tcp_synq_removed(sk, req);
+ inet_csk_reqsk_queue_unlink(sk, req, prev);
+ inet_csk_reqsk_queue_removed(sk, req);
- tcp_acceptq_queue(sk, req, child);
- return child;
+ inet_csk_reqsk_queue_add(sk, req, child);
+ return child;
- listen_overflow:
- if (!sysctl_tcp_abort_on_overflow) {
- inet_rsk(req)->acked = 1;
- return NULL;
- }
+listen_overflow:
+ if (!sysctl_tcp_abort_on_overflow) {
+ inet_rsk(req)->acked = 1;
+ return NULL;
+ }
- embryonic_reset:
- NET_INC_STATS_BH(LINUX_MIB_EMBRYONICRSTS);
- if (!(flg & TCP_FLAG_RST))
- req->rsk_ops->send_reset(skb);
+embryonic_reset:
+ NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_EMBRYONICRSTS);
+ if (!(flg & TCP_FLAG_RST))
+ req->rsk_ops->send_reset(sk, skb);
- tcp_synq_drop(sk, req, prev);
- return NULL;
+ inet_csk_reqsk_queue_drop(sk, req, prev);
+ return NULL;
}
/*
int state = child->sk_state;
if (!sock_owned_by_user(child)) {
- ret = tcp_rcv_state_process(child, skb, skb->h.th, skb->len);
-
+ ret = tcp_rcv_state_process(child, skb, tcp_hdr(skb),
+ skb->len);
/* Wakeup parent, send SIGIO */
if (state == TCP_SYN_RECV && child->sk_state != state)
parent->sk_data_ready(parent, 0);
EXPORT_SYMBOL(tcp_child_process);
EXPORT_SYMBOL(tcp_create_openreq_child);
EXPORT_SYMBOL(tcp_timewait_state_process);
-EXPORT_SYMBOL(tcp_tw_deschedule);