From a399a8053164ec8bcb06fed52be9941a26ecde11 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 8 Aug 2012 21:13:53 +0000 Subject: time: jiffies_delta_to_clock_t() helper to the rescue MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Various /proc/net files sometimes report crazy timer values, expressed in clock_t units. This happens when an expired timer delta (expires - jiffies) is passed to jiffies_to_clock_t(). This function has an overflow in : return div_u64((u64)x * TICK_NSEC, NSEC_PER_SEC / USER_HZ); commit cbbc719fccdb8cb (time: Change jiffies_to_clock_t() argument type to unsigned long) only got around the problem. As we cant output negative values in /proc/net/tcp without breaking various tools, I suggest adding a jiffies_delta_to_clock_t() wrapper that caps the negative delta to a 0 value. Signed-off-by: Eric Dumazet Reported-by: Maciej Żenczykowski Cc: Thomas Gleixner Cc: Paul Gortmaker Cc: Andrew Morton Cc: hank Signed-off-by: David S. Miller --- net/ipv6/tcp_ipv6.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) (limited to 'net/ipv6/tcp_ipv6.c') diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index c66b90f71c9b..aa41b0e6b163 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1875,7 +1875,7 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) tp->write_seq-tp->snd_una, (sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (tp->rcv_nxt - tp->copied_seq), timer_active, - jiffies_to_clock_t(timer_expires - jiffies), + jiffies_delta_to_clock_t(timer_expires - jiffies), icsk->icsk_retransmits, sock_i_uid(sp), icsk->icsk_probes_out, @@ -1895,10 +1895,7 @@ static void get_timewait6_sock(struct seq_file *seq, const struct in6_addr *dest, *src; __u16 destp, srcp; const struct inet6_timewait_sock *tw6 = inet6_twsk((struct sock *)tw); - int ttd = tw->tw_ttd - jiffies; - - if (ttd < 0) - ttd = 0; + long delta = tw->tw_ttd - jiffies; dest = &tw6->tw_v6_daddr; src = &tw6->tw_v6_rcv_saddr; @@ -1914,7 +1911,7 @@ static void get_timewait6_sock(struct seq_file *seq, dest->s6_addr32[0], dest->s6_addr32[1], dest->s6_addr32[2], dest->s6_addr32[3], destp, tw->tw_substate, 0, 0, - 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0, + 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, atomic_read(&tw->tw_refcnt), tw); } -- cgit v1.2.3 From a7cb5a49bf64ba64864ae16a6be028f8b0d3cc06 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 24 May 2012 01:10:10 -0600 Subject: userns: Print out socket uids in a user namespace aware fashion. Cc: Alexey Kuznetsov Cc: James Morris Cc: Hideaki YOSHIFUJI Cc: Patrick McHardy Cc: Arnaldo Carvalho de Melo Cc: Sridhar Samudrala Acked-by: Vlad Yasevich Acked-by: David S. Miller Acked-by: Serge Hallyn Signed-off-by: Eric W. Biederman --- include/net/tcp.h | 3 ++- init/Kconfig | 6 ------ net/appletalk/atalk_proc.c | 3 ++- net/ipv4/ping.c | 4 +++- net/ipv4/raw.c | 4 +++- net/ipv4/tcp_ipv4.c | 6 +++--- net/ipv4/udp.c | 4 +++- net/ipv6/raw.c | 3 ++- net/ipv6/tcp_ipv6.c | 6 +++--- net/ipv6/udp.c | 3 ++- net/ipx/ipx_proc.c | 3 ++- net/key/af_key.c | 2 +- net/llc/llc_proc.c | 2 +- net/packet/af_packet.c | 2 +- net/phonet/socket.c | 6 ++++-- net/sctp/proc.c | 6 ++++-- 16 files changed, 36 insertions(+), 27 deletions(-) (limited to 'net/ipv6/tcp_ipv6.c') diff --git a/include/net/tcp.h b/include/net/tcp.h index e19124b84cd2..91e746736a8f 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1509,7 +1509,8 @@ struct tcp_iter_state { sa_family_t family; enum tcp_seq_states state; struct sock *syn_wait_sk; - int bucket, offset, sbucket, num, uid; + int bucket, offset, sbucket, num; + kuid_t uid; loff_t last_pos; }; diff --git a/init/Kconfig b/init/Kconfig index 80fae193e3a1..25a6ebb50c64 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -942,10 +942,7 @@ config UIDGID_CONVERTED depends on PROC_EVENTS = n # Networking - depends on PACKET = n depends on NET_9P = n - depends on IPX = n - depends on PHONET = n depends on NET_CLS_FLOW = n depends on NETFILTER_XT_MATCH_OWNER = n depends on NETFILTER_XT_MATCH_RECENT = n @@ -953,14 +950,11 @@ config UIDGID_CONVERTED depends on NETFILTER_NETLINK_LOG = n depends on INET = n depends on IPV6 = n - depends on IP_SCTP = n depends on AF_RXRPC = n - depends on LLC2 = n depends on NET_KEY = n depends on INET_DIAG = n depends on DNS_RESOLVER = n depends on AX25 = n - depends on ATALK = n # Filesystems depends on USB_GADGETFS = n diff --git a/net/appletalk/atalk_proc.c b/net/appletalk/atalk_proc.c index b5b1a221c242..c30f3a0717fb 100644 --- a/net/appletalk/atalk_proc.c +++ b/net/appletalk/atalk_proc.c @@ -183,7 +183,8 @@ static int atalk_seq_socket_show(struct seq_file *seq, void *v) ntohs(at->dest_net), at->dest_node, at->dest_port, sk_wmem_alloc_get(s), sk_rmem_alloc_get(s), - s->sk_state, SOCK_INODE(s->sk_socket)->i_uid); + s->sk_state, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(s))); out: return 0; } diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c index 6232d476f37e..bee5eeb676f8 100644 --- a/net/ipv4/ping.c +++ b/net/ipv4/ping.c @@ -845,7 +845,9 @@ static void ping_format_sock(struct sock *sp, struct seq_file *f, bucket, src, srcp, dest, destp, sp->sk_state, sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), - 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), + 0, 0L, 0, + from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)), + 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops), len); } diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index ff0f071969ea..f2425785d40a 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -992,7 +992,9 @@ static void raw_sock_seq_show(struct seq_file *seq, struct sock *sp, int i) i, src, srcp, dest, destp, sp->sk_state, sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), - 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), + 0, 0L, 0, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), + 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops)); } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 42b2a6a73092..642be8a4c6a3 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2382,7 +2382,7 @@ 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, - struct seq_file *f, int i, int uid, int *len) + struct seq_file *f, int i, kuid_t uid, int *len) { const struct inet_request_sock *ireq = inet_rsk(req); int ttd = req->expires - jiffies; @@ -2399,7 +2399,7 @@ static void get_openreq4(const struct sock *sk, const struct request_sock *req, 1, /* timers active (only the expire timer) */ jiffies_to_clock_t(ttd), req->retrans, - uid, + from_kuid_munged(seq_user_ns(f), uid), 0, /* non standard timer */ 0, /* open_requests have no inode */ atomic_read(&sk->sk_refcnt), @@ -2450,7 +2450,7 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i, int *len) timer_active, jiffies_to_clock_t(timer_expires - jiffies), icsk->icsk_retransmits, - sock_i_uid(sk), + from_kuid_munged(seq_user_ns(f), sock_i_uid(sk)), icsk->icsk_probes_out, sock_i_ino(sk), atomic_read(&sk->sk_refcnt), sk, diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index b4c3582a991f..53b89817c008 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -2110,7 +2110,9 @@ static void udp4_format_sock(struct sock *sp, struct seq_file *f, bucket, src, srcp, dest, destp, sp->sk_state, sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), - 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), + 0, 0L, 0, + from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)), + 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops), len); } diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index ef0579d5bca6..7af88ef01657 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -1251,7 +1251,8 @@ static void raw6_sock_seq_show(struct seq_file *seq, struct sock *sp, int i) sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), 0, 0L, 0, - sock_i_uid(sp), 0, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), + 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops)); } diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index c66b90f71c9b..4b5b335ebde1 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1803,7 +1803,7 @@ static void tcp_v6_destroy_sock(struct sock *sk) #ifdef CONFIG_PROC_FS /* Proc filesystem TCPv6 sock list dumping. */ static void get_openreq6(struct seq_file *seq, - const struct sock *sk, struct request_sock *req, int i, int uid) + const struct sock *sk, struct request_sock *req, int i, kuid_t uid) { int ttd = req->expires - jiffies; const struct in6_addr *src = &inet6_rsk(req)->loc_addr; @@ -1827,7 +1827,7 @@ static void get_openreq6(struct seq_file *seq, 1, /* timers active (only the expire timer) */ jiffies_to_clock_t(ttd), req->retrans, - uid, + from_kuid_munged(seq_user_ns(seq), uid), 0, /* non standard timer */ 0, /* open_requests have no inode */ 0, req); @@ -1877,7 +1877,7 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) timer_active, jiffies_to_clock_t(timer_expires - jiffies), icsk->icsk_retransmits, - sock_i_uid(sp), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), icsk->icsk_probes_out, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 99d0077b56b8..bbdff07eebe1 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1458,7 +1458,8 @@ static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), 0, 0L, 0, - sock_i_uid(sp), 0, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), + 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops)); diff --git a/net/ipx/ipx_proc.c b/net/ipx/ipx_proc.c index f8ba30dfecae..02ff7f2f60d4 100644 --- a/net/ipx/ipx_proc.c +++ b/net/ipx/ipx_proc.c @@ -217,7 +217,8 @@ static int ipx_seq_socket_show(struct seq_file *seq, void *v) seq_printf(seq, "%08X %08X %02X %03d\n", sk_wmem_alloc_get(s), sk_rmem_alloc_get(s), - s->sk_state, SOCK_INODE(s->sk_socket)->i_uid); + s->sk_state, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(s))); out: return 0; } diff --git a/net/key/af_key.c b/net/key/af_key.c index 34e418508a67..0481d4b51476 100644 --- a/net/key/af_key.c +++ b/net/key/af_key.c @@ -3661,7 +3661,7 @@ static int pfkey_seq_show(struct seq_file *f, void *v) atomic_read(&s->sk_refcnt), sk_rmem_alloc_get(s), sk_wmem_alloc_get(s), - sock_i_uid(s), + from_kuid_munged(seq_user_ns(f), sock_i_uid(s)), sock_i_ino(s) ); return 0; diff --git a/net/llc/llc_proc.c b/net/llc/llc_proc.c index a1839c004357..7b4799cfbf8d 100644 --- a/net/llc/llc_proc.c +++ b/net/llc/llc_proc.c @@ -151,7 +151,7 @@ static int llc_seq_socket_show(struct seq_file *seq, void *v) sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk) - llc->copied_seq, sk->sk_state, - sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : -1, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), llc->link); out: return 0; diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index ceaca7c134a0..d147317ce9ea 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -3846,7 +3846,7 @@ static int packet_seq_show(struct seq_file *seq, void *v) po->ifindex, po->running, atomic_read(&s->sk_rmem_alloc), - sock_i_uid(s), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)), sock_i_ino(s)); } diff --git a/net/phonet/socket.c b/net/phonet/socket.c index 0acc943f713a..b7e982782255 100644 --- a/net/phonet/socket.c +++ b/net/phonet/socket.c @@ -612,7 +612,8 @@ static int pn_sock_seq_show(struct seq_file *seq, void *v) sk->sk_protocol, pn->sobject, pn->dobject, pn->resource, sk->sk_state, sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk), - sock_i_uid(sk), sock_i_ino(sk), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), + sock_i_ino(sk), atomic_read(&sk->sk_refcnt), sk, atomic_read(&sk->sk_drops), &len); } @@ -796,7 +797,8 @@ static int pn_res_seq_show(struct seq_file *seq, void *v) struct sock *sk = *psk; seq_printf(seq, "%02X %5d %lu%n", - (int) (psk - pnres.sk), sock_i_uid(sk), + (int) (psk - pnres.sk), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), sock_i_ino(sk), &len); } seq_printf(seq, "%*s\n", 63 - len, ""); diff --git a/net/sctp/proc.c b/net/sctp/proc.c index 1e2eee88c3ea..dc12febc977a 100644 --- a/net/sctp/proc.c +++ b/net/sctp/proc.c @@ -216,7 +216,8 @@ static int sctp_eps_seq_show(struct seq_file *seq, void *v) seq_printf(seq, "%8pK %8pK %-3d %-3d %-4d %-5d %5d %5lu ", ep, sk, sctp_sk(sk)->type, sk->sk_state, hash, epb->bind_addr.port, - sock_i_uid(sk), sock_i_ino(sk)); + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), + sock_i_ino(sk)); sctp_seq_dump_local_addrs(seq, epb); seq_printf(seq, "\n"); @@ -324,7 +325,8 @@ static int sctp_assocs_seq_show(struct seq_file *seq, void *v) assoc->assoc_id, assoc->sndbuf_used, atomic_read(&assoc->rmem_alloc), - sock_i_uid(sk), sock_i_ino(sk), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), + sock_i_ino(sk), epb->bind_addr.port, assoc->peer.port); seq_printf(seq, " "); -- cgit v1.2.3 From 8336886f786fdacbc19b719c1f7ea91eb70706d4 Mon Sep 17 00:00:00 2001 From: Jerry Chu Date: Fri, 31 Aug 2012 12:29:12 +0000 Subject: tcp: TCP Fast Open Server - support TFO listeners This patch builds on top of the previous patch to add the support for TFO listeners. This includes - 1. allocating, properly initializing, and managing the per listener fastopen_queue structure when TFO is enabled 2. changes to the inet_csk_accept code to support TFO. E.g., the request_sock can no longer be freed upon accept(), not until 3WHS finishes 3. allowing a TCP_SYN_RECV socket to properly poll() and sendmsg() if it's a TFO socket 4. properly closing a TFO listener, and a TFO socket before 3WHS finishes 5. supporting TCP_FASTOPEN socket option 6. modifying tcp_check_req() to use to check a TFO socket as well as request_sock 7. supporting TCP's TFO cookie option 8. adding a new SYN-ACK retransmit handler to use the timer directly off the TFO socket rather than the listener socket. Note that TFO server side will not retransmit anything other than SYN-ACK until the 3WHS is completed. The patch also contains an important function "reqsk_fastopen_remove()" to manage the somewhat complex relation between a listener, its request_sock, and the corresponding child socket. See the comment above the function for the detail. Signed-off-by: H.K. Jerry Chu Cc: Yuchung Cheng Cc: Neal Cardwell Cc: Eric Dumazet Cc: Tom Herbert Signed-off-by: David S. Miller --- include/net/request_sock.h | 13 ------ include/net/tcp.h | 6 ++- net/core/request_sock.c | 95 +++++++++++++++++++++++++++++++++++++++++ net/ipv4/af_inet.c | 28 +++++++++++- net/ipv4/inet_connection_sock.c | 57 ++++++++++++++++++++++--- net/ipv4/syncookies.c | 1 + net/ipv4/tcp.c | 49 ++++++++++++++++++--- net/ipv4/tcp_ipv4.c | 4 +- net/ipv4/tcp_minisocks.c | 61 +++++++++++++++++++++----- net/ipv4/tcp_output.c | 21 ++++++--- net/ipv4/tcp_timer.c | 39 ++++++++++++++++- net/ipv6/syncookies.c | 1 + net/ipv6/tcp_ipv6.c | 5 ++- 13 files changed, 330 insertions(+), 50 deletions(-) (limited to 'net/ipv6/tcp_ipv6.c') diff --git a/include/net/request_sock.h b/include/net/request_sock.h index c3cdd6c9f448..b01d8dd9ee7c 100644 --- a/include/net/request_sock.h +++ b/include/net/request_sock.h @@ -226,19 +226,6 @@ static inline struct request_sock *reqsk_queue_remove(struct request_sock_queue return req; } -static inline struct sock *reqsk_queue_get_child(struct request_sock_queue *queue, - struct sock *parent) -{ - struct request_sock *req = reqsk_queue_remove(queue); - struct sock *child = req->sk; - - WARN_ON(child == NULL); - - sk_acceptq_removed(parent); - __reqsk_free(req); - return child; -} - static inline int reqsk_queue_removed(struct request_sock_queue *queue, struct request_sock *req) { diff --git a/include/net/tcp.h b/include/net/tcp.h index 9f8821e3293a..1421b02a7905 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -424,7 +424,8 @@ extern enum tcp_tw_status tcp_timewait_state_process(struct inet_timewait_sock * const struct tcphdr *th); extern struct sock * tcp_check_req(struct sock *sk,struct sk_buff *skb, struct request_sock *req, - struct request_sock **prev); + struct request_sock **prev, + bool fastopen); extern int tcp_child_process(struct sock *parent, struct sock *child, struct sk_buff *skb); extern bool tcp_use_frto(struct sock *sk); @@ -478,7 +479,8 @@ extern int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, extern int tcp_connect(struct sock *sk); extern struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst, struct request_sock *req, - struct request_values *rvp); + struct request_values *rvp, + struct tcp_fastopen_cookie *foc); extern int tcp_disconnect(struct sock *sk, int flags); void tcp_connect_init(struct sock *sk); diff --git a/net/core/request_sock.c b/net/core/request_sock.c index 9b570a6a33c5..c31d9e8668c3 100644 --- a/net/core/request_sock.c +++ b/net/core/request_sock.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include @@ -130,3 +131,97 @@ void reqsk_queue_destroy(struct request_sock_queue *queue) kfree(lopt); } +/* + * This function is called to set a Fast Open socket's "fastopen_rsk" field + * to NULL when a TFO socket no longer needs to access the request_sock. + * This happens only after 3WHS has been either completed or aborted (e.g., + * RST is received). + * + * Before TFO, a child socket is created only after 3WHS is completed, + * hence it never needs to access the request_sock. things get a lot more + * complex with TFO. A child socket, accepted or not, has to access its + * request_sock for 3WHS processing, e.g., to retransmit SYN-ACK pkts, + * until 3WHS is either completed or aborted. Afterwards the req will stay + * until either the child socket is accepted, or in the rare case when the + * listener is closed before the child is accepted. + * + * In short, a request socket is only freed after BOTH 3WHS has completed + * (or aborted) and the child socket has been accepted (or listener closed). + * When a child socket is accepted, its corresponding req->sk is set to + * NULL since it's no longer needed. More importantly, "req->sk == NULL" + * will be used by the code below to determine if a child socket has been + * accepted or not, and the check is protected by the fastopenq->lock + * described below. + * + * Note that fastopen_rsk is only accessed from the child socket's context + * with its socket lock held. But a request_sock (req) can be accessed by + * both its child socket through fastopen_rsk, and a listener socket through + * icsk_accept_queue.rskq_accept_head. To protect the access a simple spin + * lock per listener "icsk->icsk_accept_queue.fastopenq->lock" is created. + * only in the rare case when both the listener and the child locks are held, + * e.g., in inet_csk_listen_stop() do we not need to acquire the lock. + * The lock also protects other fields such as fastopenq->qlen, which is + * decremented by this function when fastopen_rsk is no longer needed. + * + * Note that another solution was to simply use the existing socket lock + * from the listener. But first socket lock is difficult to use. It is not + * a simple spin lock - one must consider sock_owned_by_user() and arrange + * to use sk_add_backlog() stuff. But what really makes it infeasible is the + * locking hierarchy violation. E.g., inet_csk_listen_stop() may try to + * acquire a child's lock while holding listener's socket lock. A corner + * case might also exist in tcp_v4_hnd_req() that will trigger this locking + * order. + * + * When a TFO req is created, it needs to sock_hold its listener to prevent + * the latter data structure from going away. + * + * This function also sets "treq->listener" to NULL and unreference listener + * socket. treq->listener is used by the listener so it is protected by the + * fastopenq->lock in this function. + */ +void reqsk_fastopen_remove(struct sock *sk, struct request_sock *req, + bool reset) +{ + struct sock *lsk = tcp_rsk(req)->listener; + struct fastopen_queue *fastopenq = + inet_csk(lsk)->icsk_accept_queue.fastopenq; + + BUG_ON(!spin_is_locked(&sk->sk_lock.slock) && !sock_owned_by_user(sk)); + + tcp_sk(sk)->fastopen_rsk = NULL; + spin_lock_bh(&fastopenq->lock); + fastopenq->qlen--; + tcp_rsk(req)->listener = NULL; + if (req->sk) /* the child socket hasn't been accepted yet */ + goto out; + + if (!reset || lsk->sk_state != TCP_LISTEN) { + /* If the listener has been closed don't bother with the + * special RST handling below. + */ + spin_unlock_bh(&fastopenq->lock); + sock_put(lsk); + reqsk_free(req); + return; + } + /* Wait for 60secs before removing a req that has triggered RST. + * This is a simple defense against TFO spoofing attack - by + * counting the req against fastopen.max_qlen, and disabling + * TFO when the qlen exceeds max_qlen. + * + * For more details see CoNext'11 "TCP Fast Open" paper. + */ + req->expires = jiffies + 60*HZ; + if (fastopenq->rskq_rst_head == NULL) + fastopenq->rskq_rst_head = req; + else + fastopenq->rskq_rst_tail->dl_next = req; + + req->dl_next = NULL; + fastopenq->rskq_rst_tail = req; + fastopenq->qlen++; +out: + spin_unlock_bh(&fastopenq->lock); + sock_put(lsk); + return; +} diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 6681ccf5c3ee..4f70ef0b946d 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -149,6 +149,11 @@ void inet_sock_destruct(struct sock *sk) pr_err("Attempt to release alive inet socket %p\n", sk); return; } + if (sk->sk_type == SOCK_STREAM) { + struct fastopen_queue *fastopenq = + inet_csk(sk)->icsk_accept_queue.fastopenq; + kfree(fastopenq); + } WARN_ON(atomic_read(&sk->sk_rmem_alloc)); WARN_ON(atomic_read(&sk->sk_wmem_alloc)); @@ -212,6 +217,26 @@ int inet_listen(struct socket *sock, int backlog) * we can only allow the backlog to be adjusted. */ if (old_state != TCP_LISTEN) { + /* Check special setups for testing purpose to enable TFO w/o + * requiring TCP_FASTOPEN sockopt. + * Note that only TCP sockets (SOCK_STREAM) will reach here. + * Also fastopenq may already been allocated because this + * socket was in TCP_LISTEN state previously but was + * shutdown() (rather than close()). + */ + if ((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) != 0 && + inet_csk(sk)->icsk_accept_queue.fastopenq == NULL) { + if ((sysctl_tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) != 0) + err = fastopen_init_queue(sk, backlog); + else if ((sysctl_tcp_fastopen & + TFO_SERVER_WO_SOCKOPT2) != 0) + err = fastopen_init_queue(sk, + ((uint)sysctl_tcp_fastopen) >> 16); + else + err = 0; + if (err) + goto out; + } err = inet_csk_listen_start(sk, backlog); if (err) goto out; @@ -701,7 +726,8 @@ int inet_accept(struct socket *sock, struct socket *newsock, int flags) sock_rps_record_flow(sk2); WARN_ON(!((1 << sk2->sk_state) & - (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE))); + (TCPF_ESTABLISHED | TCPF_SYN_RECV | + TCPF_CLOSE_WAIT | TCPF_CLOSE))); sock_graft(sk2, newsock); diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index 7f75f21d7b83..8464b79c493f 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -283,7 +283,9 @@ static int inet_csk_wait_for_connect(struct sock *sk, long timeo) struct sock *inet_csk_accept(struct sock *sk, int flags, int *err) { struct inet_connection_sock *icsk = inet_csk(sk); + struct request_sock_queue *queue = &icsk->icsk_accept_queue; struct sock *newsk; + struct request_sock *req; int error; lock_sock(sk); @@ -296,7 +298,7 @@ struct sock *inet_csk_accept(struct sock *sk, int flags, int *err) goto out_err; /* Find already established connection */ - if (reqsk_queue_empty(&icsk->icsk_accept_queue)) { + if (reqsk_queue_empty(queue)) { long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); /* If this is a non blocking socket don't sleep */ @@ -308,14 +310,32 @@ struct sock *inet_csk_accept(struct sock *sk, int flags, int *err) if (error) goto out_err; } - - newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk); - WARN_ON(newsk->sk_state == TCP_SYN_RECV); + req = reqsk_queue_remove(queue); + newsk = req->sk; + + sk_acceptq_removed(sk); + if (sk->sk_type == SOCK_STREAM && queue->fastopenq != NULL) { + spin_lock_bh(&queue->fastopenq->lock); + if (tcp_rsk(req)->listener) { + /* We are still waiting for the final ACK from 3WHS + * so can't free req now. Instead, we set req->sk to + * NULL to signify that the child socket is taken + * so reqsk_fastopen_remove() will free the req + * when 3WHS finishes (or is aborted). + */ + req->sk = NULL; + req = NULL; + } + spin_unlock_bh(&queue->fastopenq->lock); + } out: release_sock(sk); + if (req) + __reqsk_free(req); return newsk; out_err: newsk = NULL; + req = NULL; *err = error; goto out; } @@ -720,13 +740,14 @@ EXPORT_SYMBOL_GPL(inet_csk_listen_start); void inet_csk_listen_stop(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); + struct request_sock_queue *queue = &icsk->icsk_accept_queue; struct request_sock *acc_req; struct request_sock *req; inet_csk_delete_keepalive_timer(sk); /* make all the listen_opt local to us */ - acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue); + acc_req = reqsk_queue_yank_acceptq(queue); /* Following specs, it would be better either to send FIN * (and enter FIN-WAIT-1, it is normal close) @@ -736,7 +757,7 @@ void inet_csk_listen_stop(struct sock *sk) * To be honest, we are not able to make either * of the variants now. --ANK */ - reqsk_queue_destroy(&icsk->icsk_accept_queue); + reqsk_queue_destroy(queue); while ((req = acc_req) != NULL) { struct sock *child = req->sk; @@ -754,6 +775,19 @@ void inet_csk_listen_stop(struct sock *sk) percpu_counter_inc(sk->sk_prot->orphan_count); + if (sk->sk_type == SOCK_STREAM && tcp_rsk(req)->listener) { + BUG_ON(tcp_sk(child)->fastopen_rsk != req); + BUG_ON(sk != tcp_rsk(req)->listener); + + /* Paranoid, to prevent race condition if + * an inbound pkt destined for child is + * blocked by sock lock in tcp_v4_rcv(). + * Also to satisfy an assertion in + * tcp_v4_destroy_sock(). + */ + tcp_sk(child)->fastopen_rsk = NULL; + sock_put(sk); + } inet_csk_destroy_sock(child); bh_unlock_sock(child); @@ -763,6 +797,17 @@ void inet_csk_listen_stop(struct sock *sk) sk_acceptq_removed(sk); __reqsk_free(req); } + if (queue->fastopenq != NULL) { + /* Free all the reqs queued in rskq_rst_head. */ + spin_lock_bh(&queue->fastopenq->lock); + acc_req = queue->fastopenq->rskq_rst_head; + queue->fastopenq->rskq_rst_head = NULL; + spin_unlock_bh(&queue->fastopenq->lock); + while ((req = acc_req) != NULL) { + acc_req = req->dl_next; + __reqsk_free(req); + } + } WARN_ON(sk->sk_ack_backlog); } EXPORT_SYMBOL_GPL(inet_csk_listen_stop); diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c index 650e1528e1e6..ba48e799b031 100644 --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -319,6 +319,7 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb, ireq->tstamp_ok = tcp_opt.saw_tstamp; req->ts_recent = tcp_opt.saw_tstamp ? tcp_opt.rcv_tsval : 0; treq->snt_synack = tcp_opt.saw_tstamp ? tcp_opt.rcv_tsecr : 0; + treq->listener = NULL; /* We throwed the options of the initial SYN away, so we hope * the ACK carries the same options again (see RFC1122 4.2.3.8) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 2109ff4a1daf..df83d744e380 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -486,8 +486,9 @@ unsigned int tcp_poll(struct file *file, struct socket *sock, poll_table *wait) if (sk->sk_shutdown & RCV_SHUTDOWN) mask |= POLLIN | POLLRDNORM | POLLRDHUP; - /* Connected? */ - if ((1 << sk->sk_state) & ~(TCPF_SYN_SENT | TCPF_SYN_RECV)) { + /* Connected or passive Fast Open socket? */ + if (sk->sk_state != TCP_SYN_SENT && + (sk->sk_state != TCP_SYN_RECV || tp->fastopen_rsk != NULL)) { int target = sock_rcvlowat(sk, 0, INT_MAX); if (tp->urg_seq == tp->copied_seq && @@ -840,10 +841,15 @@ static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffse ssize_t copied; long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); - /* Wait for a connection to finish. */ - if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) + /* Wait for a connection to finish. One exception is TCP Fast Open + * (passive side) where data is allowed to be sent before a connection + * is fully established. + */ + if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) && + !tcp_passive_fastopen(sk)) { if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) goto out_err; + } clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); @@ -1042,10 +1048,15 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); - /* Wait for a connection to finish. */ - if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) + /* Wait for a connection to finish. One exception is TCP Fast Open + * (passive side) where data is allowed to be sent before a connection + * is fully established. + */ + if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) && + !tcp_passive_fastopen(sk)) { if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) goto do_error; + } if (unlikely(tp->repair)) { if (tp->repair_queue == TCP_RECV_QUEUE) { @@ -2144,6 +2155,10 @@ void tcp_close(struct sock *sk, long timeout) * they look as CLOSING or LAST_ACK for Linux) * Probably, I missed some more holelets. * --ANK + * XXX (TFO) - To start off we don't support SYN+ACK+FIN + * in a single packet! (May consider it later but will + * probably need API support or TCP_CORK SYN-ACK until + * data is written and socket is closed.) */ tcp_send_fin(sk); } @@ -2215,8 +2230,16 @@ adjudge_to_death: } } - if (sk->sk_state == TCP_CLOSE) + if (sk->sk_state == TCP_CLOSE) { + struct request_sock *req = tcp_sk(sk)->fastopen_rsk; + /* We could get here with a non-NULL req if the socket is + * aborted (e.g., closed with unread data) before 3WHS + * finishes. + */ + if (req != NULL) + reqsk_fastopen_remove(sk, req, false); inet_csk_destroy_sock(sk); + } /* Otherwise, socket is reprieved until protocol close. */ out: @@ -2688,6 +2711,14 @@ static int do_tcp_setsockopt(struct sock *sk, int level, else icsk->icsk_user_timeout = msecs_to_jiffies(val); break; + + case TCP_FASTOPEN: + if (val >= 0 && ((1 << sk->sk_state) & (TCPF_CLOSE | + TCPF_LISTEN))) + err = fastopen_init_queue(sk, val); + else + err = -EINVAL; + break; default: err = -ENOPROTOOPT; break; @@ -3501,11 +3532,15 @@ EXPORT_SYMBOL(tcp_cookie_generator); void tcp_done(struct sock *sk) { + struct request_sock *req = tcp_sk(sk)->fastopen_rsk; + if (sk->sk_state == TCP_SYN_SENT || sk->sk_state == TCP_SYN_RECV) TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_ATTEMPTFAILS); tcp_set_state(sk, TCP_CLOSE); tcp_clear_xmit_timers(sk); + if (req != NULL) + reqsk_fastopen_remove(sk, req, false); sk->sk_shutdown = SHUTDOWN_MASK; diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 36f02f954ac1..bb148dee1edd 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -839,7 +839,7 @@ static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst, if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL) return -1; - skb = tcp_make_synack(sk, dst, req, rvp); + skb = tcp_make_synack(sk, dst, req, rvp, NULL); if (skb) { __tcp_v4_send_check(skb, ireq->loc_addr, ireq->rmt_addr); @@ -1554,7 +1554,7 @@ static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) 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); + return tcp_check_req(sk, skb, req, prev, false); nsk = inet_lookup_established(sock_net(sk), &tcp_hashinfo, iph->saddr, th->source, iph->daddr, th->dest, inet_iif(skb)); diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 6ff7f10dce9d..e965319d610b 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -507,6 +507,7 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, 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); + newtp->fastopen_rsk = NULL; TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_PASSIVEOPENS); } @@ -515,13 +516,18 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, EXPORT_SYMBOL(tcp_create_openreq_child); /* - * Process an incoming packet for SYN_RECV sockets represented - * as a request_sock. + * Process an incoming packet for SYN_RECV sockets represented as a + * request_sock. Normally sk is the listener socket but for TFO it + * points to the child socket. + * + * XXX (TFO) - The current impl contains a special check for ack + * validation and inside tcp_v4_reqsk_send_ack(). Can we do better? */ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, struct request_sock *req, - struct request_sock **prev) + struct request_sock **prev, + bool fastopen) { struct tcp_options_received tmp_opt; const u8 *hash_location; @@ -530,6 +536,8 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, __be32 flg = tcp_flag_word(th) & (TCP_FLAG_RST|TCP_FLAG_SYN|TCP_FLAG_ACK); bool paws_reject = false; + BUG_ON(fastopen == (sk->sk_state == TCP_LISTEN)); + tmp_opt.saw_tstamp = 0; if (th->doff > (sizeof(struct tcphdr)>>2)) { tcp_parse_options(skb, &tmp_opt, &hash_location, 0, NULL); @@ -565,6 +573,9 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, * * Enforce "SYN-ACK" according to figure 8, figure 6 * of RFC793, fixed by RFC1122. + * + * Note that even if there is new data in the SYN packet + * they will be thrown away too. */ req->rsk_ops->rtx_syn_ack(sk, req, NULL); return NULL; @@ -622,9 +633,12 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, * sent (the segment carries an unacceptable ACK) ... * a reset is sent." * - * Invalid ACK: reset will be sent by listening socket + * Invalid ACK: reset will be sent by listening socket. + * Note that the ACK validity check for a Fast Open socket is done + * elsewhere and is checked directly against the child socket rather + * than req because user data may have been sent out. */ - if ((flg & TCP_FLAG_ACK) && + if ((flg & TCP_FLAG_ACK) && !fastopen && (TCP_SKB_CB(skb)->ack_seq != tcp_rsk(req)->snt_isn + 1 + tcp_s_data_size(tcp_sk(sk)))) return sk; @@ -637,7 +651,7 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, /* RFC793: "first check sequence number". */ if (paws_reject || !tcp_in_window(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq, - tcp_rsk(req)->rcv_isn + 1, tcp_rsk(req)->rcv_isn + 1 + req->rcv_wnd)) { + tcp_rsk(req)->rcv_nxt, tcp_rsk(req)->rcv_nxt + req->rcv_wnd)) { /* Out of window: send ACK and drop. */ if (!(flg & TCP_FLAG_RST)) req->rsk_ops->send_ack(sk, skb, req); @@ -648,7 +662,7 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, /* In sequence, PAWS is OK. */ - if (tmp_opt.saw_tstamp && !after(TCP_SKB_CB(skb)->seq, tcp_rsk(req)->rcv_isn + 1)) + if (tmp_opt.saw_tstamp && !after(TCP_SKB_CB(skb)->seq, tcp_rsk(req)->rcv_nxt)) req->ts_recent = tmp_opt.rcv_tsval; if (TCP_SKB_CB(skb)->seq == tcp_rsk(req)->rcv_isn) { @@ -667,10 +681,19 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, /* ACK sequence verified above, just make sure ACK is * set. If ACK not set, just silently drop the packet. + * + * XXX (TFO) - if we ever allow "data after SYN", the + * following check needs to be removed. */ if (!(flg & TCP_FLAG_ACK)) return NULL; + /* For Fast Open no more processing is needed (sk is the + * child socket). + */ + if (fastopen) + return sk; + /* 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) { @@ -706,11 +729,21 @@ listen_overflow: } embryonic_reset: - NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_EMBRYONICRSTS); - if (!(flg & TCP_FLAG_RST)) + if (!(flg & TCP_FLAG_RST)) { + /* Received a bad SYN pkt - for TFO We try not to reset + * the local connection unless it's really necessary to + * avoid becoming vulnerable to outside attack aiming at + * resetting legit local connections. + */ req->rsk_ops->send_reset(sk, skb); - - inet_csk_reqsk_queue_drop(sk, req, prev); + } else if (fastopen) { /* received a valid RST pkt */ + reqsk_fastopen_remove(sk, req, true); + tcp_reset(sk); + } + if (!fastopen) { + inet_csk_reqsk_queue_drop(sk, req, prev); + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_EMBRYONICRSTS); + } return NULL; } EXPORT_SYMBOL(tcp_check_req); @@ -719,6 +752,12 @@ EXPORT_SYMBOL(tcp_check_req); * Queue segment on the new socket if the new socket is active, * otherwise we just shortcircuit this and continue with * the new socket. + * + * For the vast majority of cases child->sk_state will be TCP_SYN_RECV + * when entering. But other states are possible due to a race condition + * where after __inet_lookup_established() fails but before the listener + * locked is obtained, other packets cause the same connection to + * be created. */ int tcp_child_process(struct sock *parent, struct sock *child, diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index d04632673a9e..9383b51f3efc 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -702,7 +702,8 @@ static unsigned int tcp_synack_options(struct sock *sk, unsigned int mss, struct sk_buff *skb, struct tcp_out_options *opts, struct tcp_md5sig_key **md5, - struct tcp_extend_values *xvp) + struct tcp_extend_values *xvp, + struct tcp_fastopen_cookie *foc) { struct inet_request_sock *ireq = inet_rsk(req); unsigned int remaining = MAX_TCP_OPTION_SPACE; @@ -747,7 +748,15 @@ static unsigned int tcp_synack_options(struct sock *sk, if (unlikely(!ireq->tstamp_ok)) remaining -= TCPOLEN_SACKPERM_ALIGNED; } - + if (foc != NULL) { + u32 need = TCPOLEN_EXP_FASTOPEN_BASE + foc->len; + need = (need + 3) & ~3U; /* Align to 32 bits */ + if (remaining >= need) { + opts->options |= OPTION_FAST_OPEN_COOKIE; + opts->fastopen_cookie = foc; + remaining -= need; + } + } /* Similar rationale to tcp_syn_options() applies here, too. * If the options fit, the same options should fit now! */ @@ -2658,7 +2667,8 @@ int tcp_send_synack(struct sock *sk) */ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst, struct request_sock *req, - struct request_values *rvp) + struct request_values *rvp, + struct tcp_fastopen_cookie *foc) { struct tcp_out_options opts; struct tcp_extend_values *xvp = tcp_xv(rvp); @@ -2718,7 +2728,7 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst, #endif TCP_SKB_CB(skb)->when = tcp_time_stamp; tcp_header_size = tcp_synack_options(sk, req, mss, - skb, &opts, &md5, xvp) + skb, &opts, &md5, xvp, foc) + sizeof(*th); skb_push(skb, tcp_header_size); @@ -2772,7 +2782,8 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst, } th->seq = htonl(TCP_SKB_CB(skb)->seq); - th->ack_seq = htonl(tcp_rsk(req)->rcv_isn + 1); + /* XXX data is queued and acked as is. No buffer/window check */ + th->ack_seq = htonl(tcp_rsk(req)->rcv_nxt); /* RFC1323: The window in SYN & SYN/ACK segments is never scaled. */ th->window = htons(min(req->rcv_wnd, 65535U)); diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index b774a03bd1dc..fc04711e80c8 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -304,6 +304,35 @@ static void tcp_probe_timer(struct sock *sk) } } +/* + * Timer for Fast Open socket to retransmit SYNACK. Note that the + * sk here is the child socket, not the parent (listener) socket. + */ +static void tcp_fastopen_synack_timer(struct sock *sk) +{ + struct inet_connection_sock *icsk = inet_csk(sk); + int max_retries = icsk->icsk_syn_retries ? : + sysctl_tcp_synack_retries + 1; /* add one more retry for fastopen */ + struct request_sock *req; + + req = tcp_sk(sk)->fastopen_rsk; + req->rsk_ops->syn_ack_timeout(sk, req); + + if (req->retrans >= max_retries) { + tcp_write_err(sk); + return; + } + /* XXX (TFO) - Unlike regular SYN-ACK retransmit, we ignore error + * returned from rtx_syn_ack() to make it more persistent like + * regular retransmit because if the child socket has been accepted + * it's not good to give up too easily. + */ + req->rsk_ops->rtx_syn_ack(sk, req, NULL); + req->retrans++; + inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, + TCP_TIMEOUT_INIT << req->retrans, TCP_RTO_MAX); +} + /* * The TCP retransmit timer. */ @@ -317,7 +346,15 @@ void tcp_retransmit_timer(struct sock *sk) tcp_resume_early_retransmit(sk); return; } - + if (tp->fastopen_rsk) { + BUG_ON(sk->sk_state != TCP_SYN_RECV && + sk->sk_state != TCP_FIN_WAIT1); + tcp_fastopen_synack_timer(sk); + /* Before we receive ACK to our SYN-ACK don't retransmit + * anything else (e.g., data or FIN segments). + */ + return; + } if (!tp->packets_out) goto out; diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index bb46061c813a..182ab9a85d6c 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -190,6 +190,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) ireq = inet_rsk(req); ireq6 = inet6_rsk(req); treq = tcp_rsk(req); + treq->listener = NULL; if (security_inet_conn_request(sk, skb, req)) goto out_free; diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index f99b81d53cca..09078b9bc6f6 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -475,7 +475,7 @@ static int tcp_v6_send_synack(struct sock *sk, struct dst_entry *dst, if (!dst && (dst = inet6_csk_route_req(sk, fl6, req)) == NULL) goto done; - skb = tcp_make_synack(sk, dst, req, rvp); + skb = tcp_make_synack(sk, dst, req, rvp, NULL); if (skb) { __tcp_v6_send_check(skb, &treq->loc_addr, &treq->rmt_addr); @@ -987,7 +987,7 @@ static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb) &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr, inet6_iif(skb)); if (req) - return tcp_check_req(sk, skb, req, prev); + return tcp_check_req(sk, skb, req, prev, false); nsk = __inet6_lookup_established(sock_net(sk), &tcp_hashinfo, &ipv6_hdr(skb)->saddr, th->source, @@ -1179,6 +1179,7 @@ have_isn: want_cookie) goto drop_and_free; + tcp_rsk(req)->listener = NULL; inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); return 0; -- cgit v1.2.3 From 623df484a777f3c00c1ea3d6a7565b8d8ac688a1 Mon Sep 17 00:00:00 2001 From: Neal Cardwell Date: Sat, 22 Sep 2012 04:18:54 +0000 Subject: tcp: extract code to compute SYNACK RTT In preparation for adding another spot where we compute the SYNACK RTT, extract this code so that it can be shared. Signed-off-by: Neal Cardwell Signed-off-by: David S. Miller --- include/net/tcp.h | 9 +++++++++ net/ipv4/tcp_ipv4.c | 4 +--- net/ipv6/tcp_ipv6.c | 4 +--- 3 files changed, 11 insertions(+), 6 deletions(-) (limited to 'net/ipv6/tcp_ipv6.c') diff --git a/include/net/tcp.h b/include/net/tcp.h index a8cb00c0c6d9..a718d0e3d8e7 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1137,6 +1137,15 @@ static inline void tcp_openreq_init(struct request_sock *req, ireq->loc_port = tcp_hdr(skb)->dest; } +/* Compute time elapsed between SYNACK and the ACK completing 3WHS */ +static inline void tcp_synack_rtt_meas(struct sock *sk, + struct request_sock *req) +{ + if (tcp_rsk(req)->snt_synack) + tcp_valid_rtt_meas(sk, + tcp_time_stamp - tcp_rsk(req)->snt_synack); +} + extern void tcp_enter_memory_pressure(struct sock *sk); static inline int keepalive_intvl_when(const struct tcp_sock *tp) diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index e64abed249cc..1e66f7fb4fe6 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1733,9 +1733,7 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; tcp_initialize_rcv_mss(newsk); - if (tcp_rsk(req)->snt_synack) - tcp_valid_rtt_meas(newsk, - tcp_time_stamp - tcp_rsk(req)->snt_synack); + tcp_synack_rtt_meas(newsk, req); newtp->total_retrans = req->retrans; #ifdef CONFIG_TCP_MD5SIG diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index f3bfb8bbfdec..cfeeeb7fcf54 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1348,9 +1348,7 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; tcp_initialize_rcv_mss(newsk); - if (tcp_rsk(req)->snt_synack) - tcp_valid_rtt_meas(newsk, - tcp_time_stamp - tcp_rsk(req)->snt_synack); + tcp_synack_rtt_meas(newsk, req); newtp->total_retrans = req->retrans; newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; -- cgit v1.2.3 From 016818d076871c4ee34db1e8d74dc17ac1de626a Mon Sep 17 00:00:00 2001 From: Neal Cardwell Date: Sat, 22 Sep 2012 04:18:55 +0000 Subject: tcp: TCP Fast Open Server - take SYNACK RTT after completing 3WHS When taking SYNACK RTT samples for servers using TCP Fast Open, fix the code to ensure that we only call tcp_valid_rtt_meas() after we receive the ACK that completes the 3-way handshake. Previously we were always taking an RTT sample in tcp_v4_syn_recv_sock(). However, for TCP Fast Open connections tcp_v4_conn_req_fastopen() calls tcp_v4_syn_recv_sock() at the time we receive the SYN. So for TFO we must wait until tcp_rcv_state_process() to take the RTT sample. To fix this, we wait until after TFO calls tcp_v4_syn_recv_sock() before we set the snt_synack timestamp, since tcp_synack_rtt_meas() already ensures that we only take a SYNACK RTT sample if snt_synack is non-zero. To be careful, we only take a snt_synack timestamp when a SYNACK transmit or retransmit succeeds. Signed-off-by: Neal Cardwell Signed-off-by: David S. Miller --- include/net/tcp.h | 1 + net/ipv4/tcp_input.c | 1 + net/ipv4/tcp_ipv4.c | 12 +++++++++--- net/ipv6/tcp_ipv6.c | 2 +- 4 files changed, 12 insertions(+), 4 deletions(-) (limited to 'net/ipv6/tcp_ipv6.c') diff --git a/include/net/tcp.h b/include/net/tcp.h index a718d0e3d8e7..6feeccd83dd7 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1125,6 +1125,7 @@ static inline void tcp_openreq_init(struct request_sock *req, req->cookie_ts = 0; tcp_rsk(req)->rcv_isn = TCP_SKB_CB(skb)->seq; tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->seq + 1; + tcp_rsk(req)->snt_synack = 0; req->mss = rx_opt->mss_clamp; req->ts_recent = rx_opt->saw_tstamp ? rx_opt->rcv_tsval : 0; ireq->tstamp_ok = rx_opt->tstamp_ok; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index e2bec815ff23..bb326684495b 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5983,6 +5983,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb, * need req so release it. */ if (req) { + tcp_synack_rtt_meas(sk, req); reqsk_fastopen_remove(sk, req, false); } else { /* Make sure socket is routed, for diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 1e66f7fb4fe6..0a7e020f16b5 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -868,6 +868,8 @@ static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst, ireq->rmt_addr, ireq->opt); err = net_xmit_eval(err); + if (!tcp_rsk(req)->snt_synack && !err) + tcp_rsk(req)->snt_synack = tcp_time_stamp; } return err; @@ -1382,6 +1384,7 @@ static int tcp_v4_conn_req_fastopen(struct sock *sk, struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue; const struct inet_request_sock *ireq = inet_rsk(req); struct sock *child; + int err; req->retrans = 0; req->sk = NULL; @@ -1393,8 +1396,11 @@ static int tcp_v4_conn_req_fastopen(struct sock *sk, kfree_skb(skb_synack); return -1; } - ip_build_and_send_pkt(skb_synack, sk, ireq->loc_addr, - ireq->rmt_addr, ireq->opt); + err = ip_build_and_send_pkt(skb_synack, sk, ireq->loc_addr, + ireq->rmt_addr, ireq->opt); + err = net_xmit_eval(err); + if (!err) + tcp_rsk(req)->snt_synack = tcp_time_stamp; /* XXX (TFO) - is it ok to ignore error and continue? */ spin_lock(&queue->fastopenq->lock); @@ -1612,7 +1618,6 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) isn = tcp_v4_init_sequence(skb); } tcp_rsk(req)->snt_isn = isn; - tcp_rsk(req)->snt_synack = tcp_time_stamp; if (dst == NULL) { dst = inet_csk_route_req(sk, &fl4, req); @@ -1650,6 +1655,7 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) if (err || want_cookie) goto drop_and_free; + tcp_rsk(req)->snt_synack = tcp_time_stamp; tcp_rsk(req)->listener = NULL; /* Add the request_sock to the SYN table */ inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index cfeeeb7fcf54..d6212d6bc8d8 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1169,7 +1169,6 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) } have_isn: tcp_rsk(req)->snt_isn = isn; - tcp_rsk(req)->snt_synack = tcp_time_stamp; if (security_inet_conn_request(sk, skb, req)) goto drop_and_release; @@ -1180,6 +1179,7 @@ have_isn: want_cookie) goto drop_and_free; + tcp_rsk(req)->snt_synack = tcp_time_stamp; tcp_rsk(req)->listener = NULL; inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); return 0; -- cgit v1.2.3 From 861b650101eb0c627d171eb18de81dddb93d395e Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 27 Sep 2012 02:14:53 +0000 Subject: tcp: gro: add checksuming helpers skb with CHECKSUM_NONE cant currently be handled by GRO, and we notice this deep in GRO stack in tcp[46]_gro_receive() But there are cases where GRO can be a benefit, even with a lack of checksums. This preliminary work is needed to add GRO support to tunnels. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp_ipv4.c | 19 ++++++++++++++++--- net/ipv6/tcp_ipv6.c | 20 +++++++++++++++++--- 2 files changed, 33 insertions(+), 6 deletions(-) (limited to 'net/ipv6/tcp_ipv6.c') diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 385eb79cf6aa..75735c9a6a9d 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2803,6 +2803,8 @@ void tcp4_proc_exit(void) struct sk_buff **tcp4_gro_receive(struct sk_buff **head, struct sk_buff *skb) { const struct iphdr *iph = skb_gro_network_header(skb); + __wsum wsum; + __sum16 sum; switch (skb->ip_summed) { case CHECKSUM_COMPLETE: @@ -2811,11 +2813,22 @@ struct sk_buff **tcp4_gro_receive(struct sk_buff **head, struct sk_buff *skb) skb->ip_summed = CHECKSUM_UNNECESSARY; break; } - - /* fall through */ - case CHECKSUM_NONE: +flush: NAPI_GRO_CB(skb)->flush = 1; return NULL; + + case CHECKSUM_NONE: + wsum = csum_tcpudp_nofold(iph->saddr, iph->daddr, + skb_gro_len(skb), IPPROTO_TCP, 0); + sum = csum_fold(skb_checksum(skb, + skb_gro_offset(skb), + skb_gro_len(skb), + wsum)); + if (sum) + goto flush; + + skb->ip_summed = CHECKSUM_UNNECESSARY; + break; } return tcp_gro_receive(head, skb); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index d6212d6bc8d8..49c890386ce9 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -763,6 +763,8 @@ static struct sk_buff **tcp6_gro_receive(struct sk_buff **head, struct sk_buff *skb) { const struct ipv6hdr *iph = skb_gro_network_header(skb); + __wsum wsum; + __sum16 sum; switch (skb->ip_summed) { case CHECKSUM_COMPLETE: @@ -771,11 +773,23 @@ static struct sk_buff **tcp6_gro_receive(struct sk_buff **head, skb->ip_summed = CHECKSUM_UNNECESSARY; break; } - - /* fall through */ - case CHECKSUM_NONE: +flush: NAPI_GRO_CB(skb)->flush = 1; return NULL; + + case CHECKSUM_NONE: + wsum = ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr, + skb_gro_len(skb), + IPPROTO_TCP, 0)); + sum = csum_fold(skb_checksum(skb, + skb_gro_offset(skb), + skb_gro_len(skb), + wsum)); + if (sum) + goto flush; + + skb->ip_summed = CHECKSUM_UNNECESSARY; + break; } return tcp_gro_receive(head, skb); -- cgit v1.2.3