diff options
Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
-rw-r--r-- | net/ipv4/tcp_ipv4.c | 144 |
1 files changed, 112 insertions, 32 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 202cf09c4cd4..8fa32f5ae2ce 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -204,10 +204,12 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) * TIME-WAIT * and initialize rx_opt.ts_recent from it, * when trying new connection. */ - if (peer != NULL && - (u32)get_seconds() - peer->tcp_ts_stamp <= TCP_PAWS_MSL) { - tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp; - tp->rx_opt.ts_recent = peer->tcp_ts; + if (peer) { + inet_peer_refcheck(peer); + if ((u32)get_seconds() - peer->tcp_ts_stamp <= TCP_PAWS_MSL) { + tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp; + tp->rx_opt.ts_recent = peer->tcp_ts; + } } } @@ -237,7 +239,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) /* OK, now commit destination to socket. */ sk->sk_gso_type = SKB_GSO_TCPV4; - sk_setup_caps(sk, &rt->u.dst); + sk_setup_caps(sk, &rt->dst); if (!tp->write_seq) tp->write_seq = secure_tcp_sequence_number(inet->inet_saddr, @@ -793,19 +795,20 @@ static void tcp_v4_reqsk_destructor(struct request_sock *req) kfree(inet_rsk(req)->opt); } -#ifdef CONFIG_SYN_COOKIES -static void syn_flood_warning(struct sk_buff *skb) +static void syn_flood_warning(const struct sk_buff *skb) { - static unsigned long warntime; + const char *msg; - if (time_after(jiffies, (warntime + HZ * 60))) { - warntime = jiffies; - printk(KERN_INFO - "possible SYN flooding on port %d. Sending cookies.\n", - ntohs(tcp_hdr(skb)->dest)); - } -} +#ifdef CONFIG_SYN_COOKIES + if (sysctl_tcp_syncookies) + msg = "Sending cookies"; + else #endif + msg = "Dropping request"; + + pr_info("TCP: Possible SYN flooding on port %d. %s.\n", + ntohs(tcp_hdr(skb)->dest), msg); +} /* * Save and compile IPv4 options into the request_sock if needed. @@ -1243,6 +1246,8 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) * evidently real one. */ if (inet_csk_reqsk_queue_is_full(sk) && !isn) { + if (net_ratelimit()) + syn_flood_warning(skb); #ifdef CONFIG_SYN_COOKIES if (sysctl_tcp_syncookies) { want_cookie = 1; @@ -1323,15 +1328,12 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) if (security_inet_conn_request(sk, skb, req)) goto drop_and_free; - if (!want_cookie) + if (!want_cookie || tmp_opt.tstamp_ok) TCP_ECN_create_request(req, tcp_hdr(skb)); if (want_cookie) { -#ifdef CONFIG_SYN_COOKIES - syn_flood_warning(skb); - req->cookie_ts = tmp_opt.tstamp_ok; -#endif isn = cookie_v4_init_sequence(sk, skb, &req->mss); + req->cookie_ts = tmp_opt.tstamp_ok; } else if (!isn) { struct inet_peer *peer = NULL; @@ -1349,6 +1351,7 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) (dst = inet_csk_route_req(sk, req)) != NULL && (peer = rt_get_peer((struct rtable *)dst)) != NULL && peer->v4daddr == saddr) { + inet_peer_refcheck(peer); if ((u32)get_seconds() - peer->tcp_ts_stamp < TCP_PAWS_MSL && (s32)(peer->tcp_ts - req->ts_recent) > TCP_PAWS_WINDOW) { @@ -1504,7 +1507,7 @@ static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) } #ifdef CONFIG_SYN_COOKIES - if (!th->rst && !th->syn && th->ack) + if (!th->syn) sk = cookie_v4_check(sk, skb, &(IPCB(skb)->opt)); #endif return sk; @@ -1555,6 +1558,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) #endif if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ + sock_rps_save_rxhash(sk, skb->rxhash); TCP_CHECK_TIMER(sk); if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len)) { rsk = sk; @@ -1579,7 +1583,9 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) } return 0; } - } + } else + sock_rps_save_rxhash(sk, skb->rxhash); + TCP_CHECK_TIMER(sk); if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len)) { @@ -1672,8 +1678,6 @@ process: skb->dev = NULL; - sock_rps_save_rxhash(sk, skb->rxhash); - bh_lock_sock_nested(sk); ret = 0; if (!sock_owned_by_user(sk)) { @@ -1977,6 +1981,11 @@ static inline struct inet_timewait_sock *tw_next(struct inet_timewait_sock *tw) hlist_nulls_entry(tw->tw_node.next, typeof(*tw), tw_node) : NULL; } +/* + * Get next listener socket follow cur. If cur is NULL, get first socket + * starting from bucket given in st->bucket; when st->bucket is zero the + * very first socket in the hash table is returned. + */ static void *listening_get_next(struct seq_file *seq, void *cur) { struct inet_connection_sock *icsk; @@ -1987,14 +1996,15 @@ static void *listening_get_next(struct seq_file *seq, void *cur) struct net *net = seq_file_net(seq); if (!sk) { - st->bucket = 0; - ilb = &tcp_hashinfo.listening_hash[0]; + ilb = &tcp_hashinfo.listening_hash[st->bucket]; spin_lock_bh(&ilb->lock); sk = sk_nulls_head(&ilb->head); + st->offset = 0; goto get_sk; } ilb = &tcp_hashinfo.listening_hash[st->bucket]; ++st->num; + ++st->offset; if (st->state == TCP_SEQ_STATE_OPENREQ) { struct request_sock *req = cur; @@ -2009,6 +2019,7 @@ static void *listening_get_next(struct seq_file *seq, void *cur) } req = req->dl_next; } + st->offset = 0; if (++st->sbucket >= icsk->icsk_accept_queue.listen_opt->nr_table_entries) break; get_req: @@ -2044,6 +2055,7 @@ start_req: read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); } spin_unlock_bh(&ilb->lock); + st->offset = 0; if (++st->bucket < INET_LHTABLE_SIZE) { ilb = &tcp_hashinfo.listening_hash[st->bucket]; spin_lock_bh(&ilb->lock); @@ -2057,7 +2069,12 @@ out: static void *listening_get_idx(struct seq_file *seq, loff_t *pos) { - void *rc = listening_get_next(seq, NULL); + struct tcp_iter_state *st = seq->private; + void *rc; + + st->bucket = 0; + st->offset = 0; + rc = listening_get_next(seq, NULL); while (rc && *pos) { rc = listening_get_next(seq, rc); @@ -2072,13 +2089,18 @@ static inline int empty_bucket(struct tcp_iter_state *st) hlist_nulls_empty(&tcp_hashinfo.ehash[st->bucket].twchain); } +/* + * Get first established socket starting from bucket given in st->bucket. + * If st->bucket is zero, the very first socket in the hash is returned. + */ static void *established_get_first(struct seq_file *seq) { struct tcp_iter_state *st = seq->private; struct net *net = seq_file_net(seq); void *rc = NULL; - for (st->bucket = 0; st->bucket <= tcp_hashinfo.ehash_mask; ++st->bucket) { + st->offset = 0; + for (; st->bucket <= tcp_hashinfo.ehash_mask; ++st->bucket) { struct sock *sk; struct hlist_nulls_node *node; struct inet_timewait_sock *tw; @@ -2123,6 +2145,7 @@ static void *established_get_next(struct seq_file *seq, void *cur) struct net *net = seq_file_net(seq); ++st->num; + ++st->offset; if (st->state == TCP_SEQ_STATE_TIME_WAIT) { tw = cur; @@ -2139,6 +2162,7 @@ get_tw: st->state = TCP_SEQ_STATE_ESTABLISHED; /* Look for next non empty bucket */ + st->offset = 0; while (++st->bucket <= tcp_hashinfo.ehash_mask && empty_bucket(st)) ; @@ -2166,7 +2190,11 @@ out: static void *established_get_idx(struct seq_file *seq, loff_t pos) { - void *rc = established_get_first(seq); + struct tcp_iter_state *st = seq->private; + void *rc; + + st->bucket = 0; + rc = established_get_first(seq); while (rc && pos) { rc = established_get_next(seq, rc); @@ -2191,24 +2219,72 @@ static void *tcp_get_idx(struct seq_file *seq, loff_t pos) return rc; } +static void *tcp_seek_last_pos(struct seq_file *seq) +{ + struct tcp_iter_state *st = seq->private; + int offset = st->offset; + int orig_num = st->num; + void *rc = NULL; + + switch (st->state) { + case TCP_SEQ_STATE_OPENREQ: + case TCP_SEQ_STATE_LISTENING: + if (st->bucket >= INET_LHTABLE_SIZE) + break; + st->state = TCP_SEQ_STATE_LISTENING; + rc = listening_get_next(seq, NULL); + while (offset-- && rc) + rc = listening_get_next(seq, rc); + if (rc) + break; + st->bucket = 0; + /* Fallthrough */ + case TCP_SEQ_STATE_ESTABLISHED: + case TCP_SEQ_STATE_TIME_WAIT: + st->state = TCP_SEQ_STATE_ESTABLISHED; + if (st->bucket > tcp_hashinfo.ehash_mask) + break; + rc = established_get_first(seq); + while (offset-- && rc) + rc = established_get_next(seq, rc); + } + + st->num = orig_num; + + return rc; +} + static void *tcp_seq_start(struct seq_file *seq, loff_t *pos) { struct tcp_iter_state *st = seq->private; + void *rc; + + if (*pos && *pos == st->last_pos) { + rc = tcp_seek_last_pos(seq); + if (rc) + goto out; + } + st->state = TCP_SEQ_STATE_LISTENING; st->num = 0; - return *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; + st->bucket = 0; + st->offset = 0; + rc = *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; + +out: + st->last_pos = *pos; + return rc; } static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) { + struct tcp_iter_state *st = seq->private; void *rc = NULL; - struct tcp_iter_state *st; if (v == SEQ_START_TOKEN) { rc = tcp_get_idx(seq, 0); goto out; } - st = seq->private; switch (st->state) { case TCP_SEQ_STATE_OPENREQ: @@ -2216,6 +2292,8 @@ static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) rc = listening_get_next(seq, v); if (!rc) { st->state = TCP_SEQ_STATE_ESTABLISHED; + st->bucket = 0; + st->offset = 0; rc = established_get_first(seq); } break; @@ -2226,6 +2304,7 @@ static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) } out: ++*pos; + st->last_pos = *pos; return rc; } @@ -2264,6 +2343,7 @@ static int tcp_seq_open(struct inode *inode, struct file *file) s = ((struct seq_file *)file->private_data)->private; s->family = afinfo->family; + s->last_pos = 0; return 0; } |