diff options
Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
-rw-r--r-- | net/ipv4/tcp_ipv4.c | 223 |
1 files changed, 88 insertions, 135 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index f1756ee..3571f2b 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -122,7 +122,7 @@ int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp) and use initial timestamp retrieved from peer table. */ if (tcptw->tw_ts_recent_stamp && - (twp == NULL || (sysctl_tcp_tw_reuse && + (!twp || (sysctl_tcp_tw_reuse && get_seconds() - tcptw->tw_ts_recent_stamp > 1))) { tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2; if (tp->write_seq == 0) @@ -189,7 +189,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) if (!inet->inet_saddr) inet->inet_saddr = fl4->saddr; - inet->inet_rcv_saddr = inet->inet_saddr; + sk_rcv_saddr_set(sk, inet->inet_saddr); if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) { /* Reset inherited state */ @@ -204,7 +204,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) tcp_fetch_timewait_stamp(sk, &rt->dst); inet->inet_dport = usin->sin_port; - inet->inet_daddr = daddr; + sk_daddr_set(sk, daddr); inet_csk(sk)->icsk_ext_hdr_len = 0; if (inet_opt) @@ -310,6 +310,34 @@ static void do_redirect(struct sk_buff *skb, struct sock *sk) dst->ops->redirect(dst, sk, skb); } + +/* handle ICMP messages on TCP_NEW_SYN_RECV request sockets */ +void tcp_req_err(struct sock *sk, u32 seq) +{ + struct request_sock *req = inet_reqsk(sk); + struct net *net = sock_net(sk); + + /* ICMPs are not backlogged, hence we cannot get + * an established socket here. + */ + WARN_ON(req->sk); + + if (seq != tcp_rsk(req)->snt_isn) { + NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); + reqsk_put(req); + } else { + /* + * Still in SYN_RECV, just remove it silently. + * There is no good way to pass the error to the newly + * created socket, and POSIX does not want network + * errors returned from accept(). + */ + NET_INC_STATS_BH(net, LINUX_MIB_LISTENDROPS); + inet_csk_reqsk_queue_drop(req->rsk_listener, req); + } +} +EXPORT_SYMBOL(tcp_req_err); + /* * This routine is called by the ICMP module when it gets some * sort of error condition. If err < 0 then the socket should @@ -343,8 +371,9 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) int err; struct net *net = dev_net(icmp_skb->dev); - sk = inet_lookup(net, &tcp_hashinfo, iph->daddr, th->dest, - iph->saddr, th->source, inet_iif(icmp_skb)); + sk = __inet_lookup_established(net, &tcp_hashinfo, iph->daddr, + th->dest, iph->saddr, ntohs(th->source), + inet_iif(icmp_skb)); if (!sk) { ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); return; @@ -353,6 +382,9 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) inet_twsk_put(inet_twsk(sk)); return; } + seq = ntohl(th->seq); + if (sk->sk_state == TCP_NEW_SYN_RECV) + return tcp_req_err(sk, seq); bh_lock_sock(sk); /* If too many ICMPs get dropped on busy @@ -374,7 +406,6 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) icsk = inet_csk(sk); tp = tcp_sk(sk); - seq = ntohl(th->seq); /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */ fastopen = tp->fastopen_rsk; snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; @@ -458,42 +489,12 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) } switch (sk->sk_state) { - struct request_sock *req, **prev; - case TCP_LISTEN: - if (sock_owned_by_user(sk)) - goto out; - - req = inet_csk_search_req(sk, &prev, th->dest, - iph->daddr, iph->saddr); - if (!req) - goto out; - - /* ICMPs are not backlogged, hence we cannot get - an established socket here. - */ - WARN_ON(req->sk); - - if (seq != tcp_rsk(req)->snt_isn) { - NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); - goto out; - } - - /* - * Still in SYN_RECV, just remove it silently. - * There is no good way to pass the error to the newly - * created socket, and POSIX does not want network - * errors returned from accept(). - */ - inet_csk_reqsk_queue_drop(sk, req, prev); - NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); - goto out; - case TCP_SYN_SENT: case TCP_SYN_RECV: /* Only in fast or simultaneous open. If a fast open socket is * is already accepted it is treated as a connected one below. */ - if (fastopen && fastopen->sk == NULL) + if (fastopen && !fastopen->sk) break; if (!sock_owned_by_user(sk)) { @@ -647,7 +648,7 @@ static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb) if (!key) goto release_sk1; - genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, NULL, skb); + genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) goto release_sk1; } else { @@ -855,35 +856,6 @@ static void tcp_v4_reqsk_destructor(struct request_sock *req) kfree(inet_rsk(req)->opt); } -/* - * Return true if a syncookie should be sent - */ -bool tcp_syn_flood_action(struct sock *sk, - const struct sk_buff *skb, - const char *proto) -{ - const char *msg = "Dropping request"; - bool want_cookie = false; - struct listen_sock *lopt; - -#ifdef CONFIG_SYN_COOKIES - if (sysctl_tcp_syncookies) { - msg = "Sending cookies"; - want_cookie = true; - NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDOCOOKIES); - } else -#endif - NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDROP); - - lopt = inet_csk(sk)->icsk_accept_queue.listen_opt; - if (!lopt->synflood_warned && sysctl_tcp_syncookies != 2) { - lopt->synflood_warned = 1; - pr_info("%s: Possible SYN flooding on port %d. %s. Check SNMP counters.\n", - proto, ntohs(tcp_hdr(skb)->dest), msg); - } - return want_cookie; -} -EXPORT_SYMBOL(tcp_syn_flood_action); #ifdef CONFIG_TCP_MD5SIG /* @@ -897,10 +869,10 @@ struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk, const union tcp_md5_addr *addr, int family) { - struct tcp_sock *tp = tcp_sk(sk); + const struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_key *key; unsigned int size = sizeof(struct in_addr); - struct tcp_md5sig_info *md5sig; + const struct tcp_md5sig_info *md5sig; /* caller either holds rcu_read_lock() or socket lock */ md5sig = rcu_dereference_check(tp->md5sig_info, @@ -923,24 +895,15 @@ struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk, EXPORT_SYMBOL(tcp_md5_do_lookup); struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk, - struct sock *addr_sk) + const struct sock *addr_sk) { - union tcp_md5_addr *addr; + const union tcp_md5_addr *addr; - addr = (union tcp_md5_addr *)&inet_sk(addr_sk)->inet_daddr; + addr = (const union tcp_md5_addr *)&addr_sk->sk_daddr; return tcp_md5_do_lookup(sk, addr, AF_INET); } EXPORT_SYMBOL(tcp_v4_md5_lookup); -static struct tcp_md5sig_key *tcp_v4_reqsk_md5_lookup(struct sock *sk, - struct request_sock *req) -{ - union tcp_md5_addr *addr; - - addr = (union tcp_md5_addr *)&inet_rsk(req)->ir_rmt_addr; - return tcp_md5_do_lookup(sk, addr, AF_INET); -} - /* This can be called on a newly created socket, from other files */ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, int family, const u8 *newkey, u8 newkeylen, gfp_t gfp) @@ -1101,8 +1064,8 @@ clear_hash_noput: return 1; } -int tcp_v4_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key, - const struct sock *sk, const struct request_sock *req, +int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key, + const struct sock *sk, const struct sk_buff *skb) { struct tcp_md5sig_pool *hp; @@ -1110,12 +1073,9 @@ int tcp_v4_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key, const struct tcphdr *th = tcp_hdr(skb); __be32 saddr, daddr; - if (sk) { - saddr = inet_sk(sk)->inet_saddr; - daddr = inet_sk(sk)->inet_daddr; - } else if (req) { - saddr = inet_rsk(req)->ir_loc_addr; - daddr = inet_rsk(req)->ir_rmt_addr; + if (sk) { /* valid for establish/request sockets */ + saddr = sk->sk_rcv_saddr; + daddr = sk->sk_daddr; } else { const struct iphdr *iph = ip_hdr(skb); saddr = iph->saddr; @@ -1152,8 +1112,9 @@ clear_hash_noput: } EXPORT_SYMBOL(tcp_v4_md5_hash_skb); -static bool __tcp_v4_inbound_md5_hash(struct sock *sk, - const struct sk_buff *skb) +/* Called with rcu_read_lock() */ +static bool tcp_v4_inbound_md5_hash(struct sock *sk, + const struct sk_buff *skb) { /* * This gets called for each TCP segment that arrives @@ -1193,7 +1154,7 @@ static bool __tcp_v4_inbound_md5_hash(struct sock *sk, */ genhash = tcp_v4_md5_hash_skb(newhash, hash_expected, - NULL, NULL, skb); + NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) { net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s\n", @@ -1205,28 +1166,16 @@ static bool __tcp_v4_inbound_md5_hash(struct sock *sk, } return false; } - -static bool tcp_v4_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb) -{ - bool ret; - - rcu_read_lock(); - ret = __tcp_v4_inbound_md5_hash(sk, skb); - rcu_read_unlock(); - - return ret; -} - #endif -static void tcp_v4_init_req(struct request_sock *req, struct sock *sk, +static void tcp_v4_init_req(struct request_sock *req, struct sock *sk_listener, struct sk_buff *skb) { struct inet_request_sock *ireq = inet_rsk(req); - ireq->ir_loc_addr = ip_hdr(skb)->daddr; - ireq->ir_rmt_addr = ip_hdr(skb)->saddr; - ireq->no_srccheck = inet_sk(sk)->transparent; + sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr); + sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr); + ireq->no_srccheck = inet_sk(sk_listener)->transparent; ireq->opt = tcp_v4_save_options(skb); } @@ -1259,7 +1208,7 @@ struct request_sock_ops tcp_request_sock_ops __read_mostly = { static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { .mss_clamp = TCP_MSS_DEFAULT, #ifdef CONFIG_TCP_MD5SIG - .md5_lookup = tcp_v4_reqsk_md5_lookup, + .req_md5_lookup = tcp_v4_md5_lookup, .calc_md5_hash = tcp_v4_md5_hash_skb, #endif .init_req = tcp_v4_init_req, @@ -1318,8 +1267,8 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, newtp = tcp_sk(newsk); newinet = inet_sk(newsk); ireq = inet_rsk(req); - newinet->inet_daddr = ireq->ir_rmt_addr; - newinet->inet_rcv_saddr = ireq->ir_loc_addr; + sk_daddr_set(newsk, ireq->ir_rmt_addr); + sk_rcv_saddr_set(newsk, ireq->ir_loc_addr); newinet->inet_saddr = ireq->ir_loc_addr; inet_opt = ireq->opt; rcu_assign_pointer(newinet->inet_opt, inet_opt); @@ -1356,7 +1305,7 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, /* Copy over the MD5 key from the original socket */ key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&newinet->inet_daddr, AF_INET); - if (key != NULL) { + if (key) { /* * We're using one, so create a matching key * on the newsk structure. If we fail to get @@ -1391,15 +1340,17 @@ EXPORT_SYMBOL(tcp_v4_syn_recv_sock); static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) { - struct tcphdr *th = tcp_hdr(skb); + const struct tcphdr *th = tcp_hdr(skb); const struct iphdr *iph = ip_hdr(skb); + struct request_sock *req; struct sock *nsk; - struct request_sock **prev; - /* Find possible connection requests. */ - struct request_sock *req = inet_csk_search_req(sk, &prev, th->source, - iph->saddr, iph->daddr); - if (req) - return tcp_check_req(sk, skb, req, prev, false); + + req = inet_csk_search_req(sk, th->source, iph->saddr, iph->daddr); + if (req) { + nsk = tcp_check_req(sk, skb, req, false); + reqsk_put(req); + return nsk; + } nsk = inet_lookup_established(sock_net(sk), &tcp_hashinfo, iph->saddr, th->source, iph->daddr, th->dest, inet_iif(skb)); @@ -1439,7 +1390,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) sk_mark_napi_id(sk, skb); if (dst) { if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || - dst->ops->check(dst, 0) == NULL) { + !dst->ops->check(dst, 0)) { dst_release(dst); sk->sk_rx_dst = NULL; } @@ -1517,7 +1468,7 @@ void tcp_v4_early_demux(struct sk_buff *skb) if (sk) { skb->sk = sk; skb->destructor = sock_edemux; - if (sk->sk_state != TCP_TIME_WAIT) { + if (sk_fullsock(sk)) { struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); if (dst) @@ -1734,7 +1685,7 @@ do_time_wait: iph->daddr, th->dest, inet_iif(skb)); if (sk2) { - inet_twsk_deschedule(inet_twsk(sk), &tcp_death_row); + inet_twsk_deschedule(inet_twsk(sk)); inet_twsk_put(inet_twsk(sk)); sk = sk2; goto process; @@ -1846,7 +1797,7 @@ void tcp_v4_destroy_sock(struct sock *sk) if (inet_csk(sk)->icsk_bind_hash) inet_put_port(sk); - BUG_ON(tp->fastopen_rsk != NULL); + BUG_ON(tp->fastopen_rsk); /* If socket is aborted during connect operation */ tcp_free_fastopen_req(tp); @@ -1904,13 +1855,13 @@ get_req: } sk = sk_nulls_next(st->syn_wait_sk); st->state = TCP_SEQ_STATE_LISTENING; - read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); + spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); } else { icsk = inet_csk(sk); - read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); + spin_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); if (reqsk_queue_len(&icsk->icsk_accept_queue)) goto start_req; - read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); + spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); sk = sk_nulls_next(sk); } get_sk: @@ -1922,7 +1873,7 @@ get_sk: goto out; } icsk = inet_csk(sk); - read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); + spin_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); if (reqsk_queue_len(&icsk->icsk_accept_queue)) { start_req: st->uid = sock_i_uid(sk); @@ -1931,7 +1882,7 @@ start_req: st->sbucket = 0; goto get_req; } - read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); + spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); } spin_unlock_bh(&ilb->lock); st->offset = 0; @@ -2150,7 +2101,7 @@ static void tcp_seq_stop(struct seq_file *seq, void *v) case TCP_SEQ_STATE_OPENREQ: if (v) { struct inet_connection_sock *icsk = inet_csk(st->syn_wait_sk); - read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); + spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); } case TCP_SEQ_STATE_LISTENING: if (v != SEQ_START_TOKEN) @@ -2204,17 +2155,17 @@ void tcp_proc_unregister(struct net *net, struct tcp_seq_afinfo *afinfo) } EXPORT_SYMBOL(tcp_proc_unregister); -static void get_openreq4(const struct sock *sk, const struct request_sock *req, +static void get_openreq4(const struct request_sock *req, struct seq_file *f, int i, kuid_t uid) { const struct inet_request_sock *ireq = inet_rsk(req); - long delta = req->expires - jiffies; + long delta = req->rsk_timer.expires - jiffies; seq_printf(f, "%4d: %08X:%04X %08X:%04X" " %02X %08X:%08X %02X:%08lX %08X %5u %8d %u %d %pK", i, ireq->ir_loc_addr, - ntohs(inet_sk(sk)->inet_sport), + ireq->ir_num, ireq->ir_rmt_addr, ntohs(ireq->ir_rmt_port), TCP_SYN_RECV, @@ -2225,7 +2176,7 @@ static void get_openreq4(const struct sock *sk, const struct request_sock *req, from_kuid_munged(seq_user_ns(f), uid), 0, /* non standard timer */ 0, /* open_requests have no inode */ - atomic_read(&sk->sk_refcnt), + 0, req); } @@ -2291,9 +2242,9 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i) static void get_timewait4_sock(const struct inet_timewait_sock *tw, struct seq_file *f, int i) { + long delta = tw->tw_timer.expires - jiffies; __be32 dest, src; __u16 destp, srcp; - s32 delta = tw->tw_ttd - inet_tw_time_stamp(); dest = tw->tw_daddr; src = tw->tw_rcv_saddr; @@ -2332,7 +2283,7 @@ static int tcp4_seq_show(struct seq_file *seq, void *v) get_tcp4_sock(v, seq, st->num); break; case TCP_SEQ_STATE_OPENREQ: - get_openreq4(st->syn_wait_sk, v, seq, st->num, st->uid); + get_openreq4(v, seq, st->num, st->uid); break; } out: @@ -2460,6 +2411,8 @@ static int __net_init tcp_sk_init(struct net *net) } net->ipv4.sysctl_tcp_ecn = 2; net->ipv4.sysctl_tcp_base_mss = TCP_BASE_MSS; + net->ipv4.sysctl_tcp_probe_threshold = TCP_PROBE_THRESHOLD; + net->ipv4.sysctl_tcp_probe_interval = TCP_PROBE_INTERVAL; return 0; fail: |