X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=net%2Fipv4%2Ftcp_minisocks.c;h=96852af43ca72c9de332a31e20a0f7f6cb1cf8a1;hb=435cf559f02ea3a3159eb316f97dc88bdebe9432;hp=f8e288c8d69374a22f1bfc1cc3cc753a76672696;hpb=e6848976b721eeb5551cd94673faafeef78d9f35;p=safe%2Fjmp%2Flinux-2.6 diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index f8e288c..96852af 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -5,8 +5,6 @@ * * 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, * Mark Evans, @@ -20,7 +18,6 @@ * Jorge Cwik, */ -#include #include #include #include @@ -29,19 +26,28 @@ #include #include -#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; -int sysctl_tcp_syncookies = SYNC_INIT; -int sysctl_tcp_abort_on_overflow; +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 */ -static void tcp_tw_schedule(struct tcp_tw_bucket *tw, int timeo); + .twcal_hand = -1, + .twcal_timer = TIMER_INITIALIZER(inet_twdr_twcal_tick, 0, + (unsigned long)&tcp_death_row), +}; + +EXPORT_SYMBOL_GPL(tcp_death_row); static __inline__ int tcp_in_window(u32 seq, u32 end_seq, u32 s_win, u32 e_win) { @@ -52,48 +58,7 @@ 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; - - -/* Must be called with locally disabled BHs. */ -static void tcp_timewait_kill(struct tcp_tw_bucket *tw) -{ - struct tcp_ehash_bucket *ehead; - struct tcp_bind_hashbucket *bhead; - struct tcp_bind_bucket *tb; - - /* Unlink from established hashes. */ - ehead = &tcp_ehash[tw->tw_hashent]; - write_lock(&ehead->lock); - if (hlist_unhashed(&tw->tw_node)) { - write_unlock(&ehead->lock); - return; - } - __hlist_del(&tw->tw_node); - sk_node_init(&tw->tw_node); - write_unlock(&ehead->lock); - - /* Disassociate with bind bucket. */ - bhead = &tcp_bhash[tcp_bhashfn(tw->tw_num)]; - spin_lock(&bhead->lock); - tb = tw->tw_tb; - __hlist_del(&tw->tw_bind_node); - tw->tw_tb = NULL; - tcp_bucket_destroy(tb); - spin_unlock(&bhead->lock); - -#ifdef SOCK_REFCNT_DEBUG - if (atomic_read(&tw->tw_refcnt) != 1) { - printk(KERN_DEBUG "tw_bucket %p refcnt=%d\n", tw, - atomic_read(&tw->tw_refcnt)); - } -#endif - tcp_tw_put(tw); -} - -/* +/* * * 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. @@ -122,20 +87,21 @@ static void tcp_timewait_kill(struct tcp_tw_bucket *tw) * to avoid misread sequence numbers, states etc. --ANK */ enum tcp_tw_status -tcp_timewait_state_process(struct tcp_tw_bucket *tw, struct sk_buff *skb, - struct tcphdr *th, unsigned len) +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; int paws_reject = 0; - tmp_opt.saw_tstamp = 0; - if (th->doff > (sizeof(struct tcphdr) >> 2) && tw->tw_ts_recent_stamp) { - tcp_parse_options(skb, &tmp_opt, 0); + if (th->doff > (sizeof(*th) >> 2) && tcptw->tw_ts_recent_stamp) { + tmp_opt.tstamp_ok = 1; + tcp_parse_options(skb, &tmp_opt, 1, NULL); if (tmp_opt.saw_tstamp) { - tmp_opt.ts_recent = tw->tw_ts_recent; - tmp_opt.ts_recent_stamp = tw->tw_ts_recent_stamp; - paws_reject = tcp_paws_check(&tmp_opt, th->rst); + tmp_opt.ts_recent = tcptw->tw_ts_recent; + tmp_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; + paws_reject = tcp_paws_reject(&tmp_opt, th->rst); } } @@ -145,20 +111,21 @@ tcp_timewait_state_process(struct tcp_tw_bucket *tw, struct sk_buff *skb, /* Out of window, send ACK */ if (paws_reject || !tcp_in_window(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq, - tw->tw_rcv_nxt, - tw->tw_rcv_nxt + tw->tw_rcv_wnd)) + tcptw->tw_rcv_nxt, + tcptw->tw_rcv_nxt + tcptw->tw_rcv_wnd)) return TCP_TW_ACK; if (th->rst) goto kill; - if (th->syn && !before(TCP_SKB_CB(skb)->seq, tw->tw_rcv_nxt)) + if (th->syn && !before(TCP_SKB_CB(skb)->seq, tcptw->tw_rcv_nxt)) goto kill_with_rst; /* Dup ACK? */ - if (!after(TCP_SKB_CB(skb)->end_seq, tw->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) { - tcp_tw_put(tw); + inet_twsk_put(tw); return TCP_TW_SUCCESS; } @@ -166,32 +133,34 @@ tcp_timewait_state_process(struct tcp_tw_bucket *tw, struct sk_buff *skb, * reset. */ if (!th->fin || - TCP_SKB_CB(skb)->end_seq != tw->tw_rcv_nxt + 1) { + TCP_SKB_CB(skb)->end_seq != tcptw->tw_rcv_nxt + 1) { kill_with_rst: - tcp_tw_deschedule(tw); - tcp_tw_put(tw); + inet_twsk_deschedule(tw, &tcp_death_row); + inet_twsk_put(tw); return TCP_TW_RST; } /* FIN arrived, enter true time-wait state. */ - tw->tw_substate = TCP_TIME_WAIT; - tw->tw_rcv_nxt = TCP_SKB_CB(skb)->end_seq; + tw->tw_substate = TCP_TIME_WAIT; + tcptw->tw_rcv_nxt = TCP_SKB_CB(skb)->end_seq; if (tmp_opt.saw_tstamp) { - tw->tw_ts_recent_stamp = xtime.tv_sec; - tw->tw_ts_recent = tmp_opt.rcv_tsval; + 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 && tw->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; } @@ -202,41 +171,42 @@ kill_with_rst: * "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". */ if (!paws_reject && - (TCP_SKB_CB(skb)->seq == tw->tw_rcv_nxt && + (TCP_SKB_CB(skb)->seq == tcptw->tw_rcv_nxt && (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq || th->rst))) { /* 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); - tcp_tw_put(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) { - tw->tw_ts_recent = tmp_opt.rcv_tsval; - tw->tw_ts_recent_stamp = xtime.tv_sec; + tcptw->tw_ts_recent = tmp_opt.rcv_tsval; + tcptw->tw_ts_recent_stamp = get_seconds(); } - tcp_tw_put(tw); + inet_twsk_put(tw); return TCP_TW_SUCCESS; } @@ -258,9 +228,10 @@ kill: */ if (th->syn && !th->rst && !th->ack && !paws_reject && - (after(TCP_SKB_CB(skb)->seq, tw->tw_rcv_nxt) || - (tmp_opt.saw_tstamp && (s32)(tw->tw_ts_recent - tmp_opt.rcv_tsval) < 0))) { - u32 isn = tw->tw_snd_nxt + 65535 + 2; + (after(TCP_SKB_CB(skb)->seq, tcptw->tw_rcv_nxt) || + (tmp_opt.saw_tstamp && + (s32)(tcptw->tw_ts_recent - tmp_opt.rcv_tsval) < 0))) { + u32 isn = tcptw->tw_snd_nxt + 65535 + 2; if (isn == 0) isn++; TCP_SKB_CB(skb)->when = isn; @@ -268,9 +239,9 @@ kill: } 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 @@ -278,107 +249,81 @@ kill: * 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_ACK; } - tcp_tw_put(tw); + inet_twsk_put(tw); return TCP_TW_SUCCESS; } -/* Enter the time wait state. This is called with locally disabled BH. - * Essentially we whip up a timewait bucket, copy the - * relevant info into it from the SK, and mess with hash chains - * and list linkage. +/* + * Move a socket to time-wait or dead fin-wait-2 state. */ -static void __tcp_tw_hashdance(struct sock *sk, struct tcp_tw_bucket *tw) +void tcp_time_wait(struct sock *sk, int state, int timeo) { - struct tcp_ehash_bucket *ehead = &tcp_ehash[sk->sk_hashent]; - struct tcp_bind_hashbucket *bhead; - - /* Step 1: Put TW into bind hash. Original socket stays there too. - Note, that any socket with inet_sk(sk)->num != 0 MUST be bound in - binding cache, even if it is closed. - */ - bhead = &tcp_bhash[tcp_bhashfn(inet_sk(sk)->num)]; - spin_lock(&bhead->lock); - tw->tw_tb = tcp_sk(sk)->bind_hash; - BUG_TRAP(tcp_sk(sk)->bind_hash); - tw_add_bind_node(tw, &tw->tw_tb->owners); - spin_unlock(&bhead->lock); + 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; - write_lock(&ehead->lock); + if (tcp_death_row.sysctl_tw_recycle && tp->rx_opt.ts_recent_stamp) + recycle_ok = icsk->icsk_af_ops->remember_stamp(sk); - /* Step 2: Remove SK from established hash. */ - if (__sk_del_node_init(sk)) - sock_prot_dec_use(sk->sk_prot); + if (tcp_death_row.tw_count < tcp_death_row.sysctl_max_tw_buckets) + tw = inet_twsk_alloc(sk, state); - /* Step 3: Hash TW into TIMEWAIT half of established hash table. */ - tw_add_node(tw, &(ehead + tcp_ehash_size)->chain); - atomic_inc(&tw->tw_refcnt); + if (tw != NULL) { + struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw); + const int rto = (icsk->icsk_rto << 2) - (icsk->icsk_rto >> 1); - write_unlock(&ehead->lock); -} - -/* - * Move a socket to time-wait or dead fin-wait-2 state. - */ -void tcp_time_wait(struct sock *sk, int state, int timeo) -{ - struct tcp_tw_bucket *tw = NULL; - 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_tw_count < sysctl_tcp_max_tw_buckets) - tw = kmem_cache_alloc(tcp_timewait_cachep, SLAB_ATOMIC); - - if(tw != NULL) { - struct inet_sock *inet = inet_sk(sk); - int rto = (tp->rto<<2) - (tp->rto>>1); - - /* Give us an identity. */ - tw->tw_daddr = inet->daddr; - tw->tw_rcv_saddr = inet->rcv_saddr; - tw->tw_bound_dev_if = sk->sk_bound_dev_if; - tw->tw_num = inet->num; - tw->tw_state = TCP_TIME_WAIT; - tw->tw_substate = state; - tw->tw_sport = inet->sport; - tw->tw_dport = inet->dport; - tw->tw_family = sk->sk_family; - tw->tw_reuse = sk->sk_reuse; tw->tw_rcv_wscale = tp->rx_opt.rcv_wscale; - atomic_set(&tw->tw_refcnt, 1); - - tw->tw_hashent = sk->sk_hashent; - tw->tw_rcv_nxt = tp->rcv_nxt; - tw->tw_snd_nxt = tp->snd_nxt; - tw->tw_rcv_wnd = tcp_receive_window(tp); - tw->tw_ts_recent = tp->rx_opt.ts_recent; - tw->tw_ts_recent_stamp = tp->rx_opt.ts_recent_stamp; - tw_dead_node_init(tw); + tcptw->tw_rcv_nxt = tp->rcv_nxt; + tcptw->tw_snd_nxt = tp->snd_nxt; + tcptw->tw_rcv_wnd = tcp_receive_window(tp); + tcptw->tw_ts_recent = tp->rx_opt.ts_recent; + tcptw->tw_ts_recent_stamp = tp->rx_opt.ts_recent_stamp; #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) if (tw->tw_family == PF_INET6) { struct ipv6_pinfo *np = inet6_sk(sk); + struct inet6_timewait_sock *tw6; - ipv6_addr_copy(&tw->tw_v6_daddr, &np->daddr); - ipv6_addr_copy(&tw->tw_v6_rcv_saddr, &np->rcv_saddr); - tw->tw_v6_ipv6only = np->ipv6only; - } else { - memset(&tw->tw_v6_daddr, 0, sizeof(tw->tw_v6_daddr)); - memset(&tw->tw_v6_rcv_saddr, 0, sizeof(tw->tw_v6_rcv_saddr)); - tw->tw_v6_ipv6only = 0; + 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. */ - __tcp_tw_hashdance(sk, tw); + __inet_twsk_hashdance(tw, sk, &tcp_hashinfo); /* Get the TIME_WAIT timeout firing. */ if (timeo < rto) @@ -392,290 +337,36 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) timeo = TCP_TIMEWAIT_LEN; } - tcp_tw_schedule(tw, timeo); - tcp_tw_put(tw); + 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) -{ - struct tcp_tw_bucket *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: - tw_for_each_inmate(tw, node, &tcp_tw_death_row[slot]) { - __tw_del_dead_node(tw); - spin_unlock(&tw_death_lock); - tcp_timewait_kill(tw); - tcp_tw_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) +void tcp_twsk_destructor(struct sock *sk) { - 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 tcp_tw_bucket *tw) -{ - spin_lock(&tw_death_lock); - if (tw_del_dead_node(tw)) { - tcp_tw_put(tw); - if (--tcp_tw_count == 0) - del_timer(&tcp_tw_timer); - } - spin_unlock(&tw_death_lock); - tcp_timewait_kill(tw); +#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 tcp_tw_bucket *tw, 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; - - spin_lock(&tw_death_lock); - - /* Unlink it, if it was scheduled */ - if (tw_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<tw_death_node, list); - - if (tcp_tw_count++ == 0) - mod_timer(&tcp_tw_timer, jiffies+TCP_TWKILL_PERIOD); - spin_unlock(&tw_death_lock); -} - -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; necn_flags = inet_rsk(req)->ecn_ok ? TCP_ECN_OK : 0; } /* This is not only more efficient than what we used to do, it eliminates @@ -686,82 +377,63 @@ out: */ 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 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); - tcp_sk(newsk)->bind_hash = NULL; - - /* Clone the TCP header template */ - inet_sk(newsk)->dport = ireq->rmt_port; - - sock_lock_init(newsk); - bh_lock_sock(newsk); - - rwlock_init(&newsk->sk_dst_lock); - 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 @@ -770,62 +442,34 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, */ 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; @@ -838,48 +482,51 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, 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); + 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; struct tcp_options_received tmp_opt; struct sock *child; - tmp_opt.saw_tstamp = 0; - if (th->doff > (sizeof(struct tcphdr)>>2)) { - tcp_parse_options(skb, &tmp_opt, 0); + if ((th->doff > (sizeof(struct tcphdr)>>2)) && (req->ts_recent)) { + tmp_opt.tstamp_ok = 1; + tcp_parse_options(skb, &tmp_opt, 1, NULL); if (tmp_opt.saw_tstamp) { tmp_opt.ts_recent = req->ts_recent; @@ -887,8 +534,8 @@ struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb, * it can be estimated (approximately) * from another data. */ - tmp_opt.ts_recent_stamp = xtime.tv_sec - ((TCP_TIMEOUT_INIT/HZ)<retrans); - paws_reject = tcp_paws_check(&tmp_opt, th->rst); + tmp_opt.ts_recent_stamp = get_seconds() - ((TCP_TIMEOUT_INIT/HZ)<retrans); + paws_reject = tcp_paws_reject(&tmp_opt, th->rst); } } @@ -946,9 +593,10 @@ struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb, 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. @@ -965,13 +613,14 @@ struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb, /* 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 @@ -985,70 +634,73 @@ struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb, 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; } /* @@ -1064,8 +716,8 @@ int tcp_child_process(struct sock *parent, struct sock *child, 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); @@ -1086,4 +738,3 @@ EXPORT_SYMBOL(tcp_check_req); EXPORT_SYMBOL(tcp_child_process); EXPORT_SYMBOL(tcp_create_openreq_child); EXPORT_SYMBOL(tcp_timewait_state_process); -EXPORT_SYMBOL(tcp_tw_deschedule);