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-rw-r--r--include/net/tcp.h164
1 files changed, 120 insertions, 44 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h
index f75a04d752cb..e19124b84cd2 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -123,7 +123,7 @@ extern void tcp_time_wait(struct sock *sk, int state, int timeo);
#endif
#define TCP_RTO_MAX ((unsigned)(120*HZ))
#define TCP_RTO_MIN ((unsigned)(HZ/5))
-#define TCP_TIMEOUT_INIT ((unsigned)(1*HZ)) /* RFC2988bis initial RTO value */
+#define TCP_TIMEOUT_INIT ((unsigned)(1*HZ)) /* RFC6298 2.1 initial RTO value */
#define TCP_TIMEOUT_FALLBACK ((unsigned)(3*HZ)) /* RFC 1122 initial RTO value, now
* used as a fallback RTO for the
* initial data transmission if no
@@ -170,6 +170,11 @@ extern void tcp_time_wait(struct sock *sk, int state, int timeo);
#define TCPOPT_TIMESTAMP 8 /* Better RTT estimations/PAWS */
#define TCPOPT_MD5SIG 19 /* MD5 Signature (RFC2385) */
#define TCPOPT_COOKIE 253 /* Cookie extension (experimental) */
+#define TCPOPT_EXP 254 /* Experimental */
+/* Magic number to be after the option value for sharing TCP
+ * experimental options. See draft-ietf-tcpm-experimental-options-00.txt
+ */
+#define TCPOPT_FASTOPEN_MAGIC 0xF989
/*
* TCP option lengths
@@ -180,6 +185,7 @@ extern void tcp_time_wait(struct sock *sk, int state, int timeo);
#define TCPOLEN_SACK_PERM 2
#define TCPOLEN_TIMESTAMP 10
#define TCPOLEN_MD5SIG 18
+#define TCPOLEN_EXP_FASTOPEN_BASE 4
#define TCPOLEN_COOKIE_BASE 2 /* Cookie-less header extension */
#define TCPOLEN_COOKIE_PAIR 3 /* Cookie pair header extension */
#define TCPOLEN_COOKIE_MIN (TCPOLEN_COOKIE_BASE+TCP_COOKIE_MIN)
@@ -206,6 +212,10 @@ extern void tcp_time_wait(struct sock *sk, int state, int timeo);
/* TCP initial congestion window as per draft-hkchu-tcpm-initcwnd-01 */
#define TCP_INIT_CWND 10
+/* Bit Flags for sysctl_tcp_fastopen */
+#define TFO_CLIENT_ENABLE 1
+#define TFO_CLIENT_NO_COOKIE 4 /* Data in SYN w/o cookie option */
+
extern struct inet_timewait_death_row tcp_death_row;
/* sysctl variables for tcp */
@@ -222,6 +232,7 @@ extern int sysctl_tcp_retries1;
extern int sysctl_tcp_retries2;
extern int sysctl_tcp_orphan_retries;
extern int sysctl_tcp_syncookies;
+extern int sysctl_tcp_fastopen;
extern int sysctl_tcp_retrans_collapse;
extern int sysctl_tcp_stdurg;
extern int sysctl_tcp_rfc1337;
@@ -252,6 +263,9 @@ extern int sysctl_tcp_max_ssthresh;
extern int sysctl_tcp_cookie_size;
extern int sysctl_tcp_thin_linear_timeouts;
extern int sysctl_tcp_thin_dupack;
+extern int sysctl_tcp_early_retrans;
+extern int sysctl_tcp_limit_output_bytes;
+extern int sysctl_tcp_challenge_ack_limit;
extern atomic_long_t tcp_memory_allocated;
extern struct percpu_counter tcp_sockets_allocated;
@@ -262,14 +276,14 @@ extern int tcp_memory_pressure;
* and worry about wraparound (automatic with unsigned arithmetic).
*/
-static inline int before(__u32 seq1, __u32 seq2)
+static inline bool before(__u32 seq1, __u32 seq2)
{
return (__s32)(seq1-seq2) < 0;
}
#define after(seq2, seq1) before(seq1, seq2)
/* is s2<=s1<=s3 ? */
-static inline int between(__u32 seq1, __u32 seq2, __u32 seq3)
+static inline bool between(__u32 seq1, __u32 seq2, __u32 seq3)
{
return seq3 - seq2 >= seq1 - seq2;
}
@@ -304,7 +318,7 @@ static inline void tcp_synq_overflow(struct sock *sk)
}
/* syncookies: no recent synqueue overflow on this listening socket? */
-static inline int tcp_synq_no_recent_overflow(const struct sock *sk)
+static inline bool tcp_synq_no_recent_overflow(const struct sock *sk)
{
unsigned long last_overflow = tcp_sk(sk)->rx_opt.ts_recent_stamp;
return time_after(jiffies, last_overflow + TCP_TIMEOUT_FALLBACK);
@@ -320,19 +334,24 @@ extern struct proto tcp_prot;
extern void tcp_init_mem(struct net *net);
+extern void tcp_tasklet_init(void);
+
extern void tcp_v4_err(struct sk_buff *skb, u32);
extern void tcp_shutdown (struct sock *sk, int how);
+extern void tcp_v4_early_demux(struct sk_buff *skb);
extern int tcp_v4_rcv(struct sk_buff *skb);
-extern struct inet_peer *tcp_v4_get_peer(struct sock *sk, bool *release_it);
-extern void *tcp_v4_tw_get_peer(struct sock *sk);
+extern struct inet_peer *tcp_v4_get_peer(struct sock *sk);
extern int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw);
extern int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
size_t size);
extern int tcp_sendpage(struct sock *sk, struct page *page, int offset,
size_t size, int flags);
+extern void tcp_release_cb(struct sock *sk);
+extern void tcp_write_timer_handler(struct sock *sk);
+extern void tcp_delack_timer_handler(struct sock *sk);
extern int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg);
extern int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
const struct tcphdr *th, unsigned int len);
@@ -366,13 +385,6 @@ static inline void tcp_dec_quickack_mode(struct sock *sk,
#define TCP_ECN_DEMAND_CWR 4
#define TCP_ECN_SEEN 8
-static __inline__ void
-TCP_ECN_create_request(struct request_sock *req, struct tcphdr *th)
-{
- if (sysctl_tcp_ecn && th->ece && th->cwr)
- inet_rsk(req)->ecn_ok = 1;
-}
-
enum tcp_tw_status {
TCP_TW_SUCCESS = 0,
TCP_TW_RST = 1,
@@ -389,12 +401,26 @@ extern struct sock * tcp_check_req(struct sock *sk,struct sk_buff *skb,
struct request_sock **prev);
extern int tcp_child_process(struct sock *parent, struct sock *child,
struct sk_buff *skb);
-extern int tcp_use_frto(struct sock *sk);
+extern bool tcp_use_frto(struct sock *sk);
extern void tcp_enter_frto(struct sock *sk);
extern void tcp_enter_loss(struct sock *sk, int how);
extern void tcp_clear_retrans(struct tcp_sock *tp);
extern void tcp_update_metrics(struct sock *sk);
+extern void tcp_init_metrics(struct sock *sk);
+extern void tcp_metrics_init(void);
+extern bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst, bool paws_check);
+extern bool tcp_remember_stamp(struct sock *sk);
+extern bool tcp_tw_remember_stamp(struct inet_timewait_sock *tw);
+extern void tcp_fastopen_cache_get(struct sock *sk, u16 *mss,
+ struct tcp_fastopen_cookie *cookie,
+ int *syn_loss, unsigned long *last_syn_loss);
+extern void tcp_fastopen_cache_set(struct sock *sk, u16 mss,
+ struct tcp_fastopen_cookie *cookie,
+ bool syn_lost);
+extern void tcp_fetch_timewait_stamp(struct sock *sk, struct dst_entry *dst);
+extern void tcp_disable_fack(struct tcp_sock *tp);
extern void tcp_close(struct sock *sk, long timeout);
+extern void tcp_init_sock(struct sock *sk);
extern unsigned int tcp_poll(struct file * file, struct socket *sock,
struct poll_table_struct *wait);
extern int tcp_getsockopt(struct sock *sk, int level, int optname,
@@ -411,7 +437,7 @@ extern int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
size_t len, int nonblock, int flags, int *addr_len);
extern void tcp_parse_options(const struct sk_buff *skb,
struct tcp_options_received *opt_rx, const u8 **hvpp,
- int estab);
+ int estab, struct tcp_fastopen_cookie *foc);
extern const u8 *tcp_parse_md5sig_option(const struct tcphdr *th);
/*
@@ -435,6 +461,9 @@ extern struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst,
struct request_values *rvp);
extern int tcp_disconnect(struct sock *sk, int flags);
+void tcp_connect_init(struct sock *sk);
+void tcp_finish_connect(struct sock *sk, struct sk_buff *skb);
+int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size);
/* From syncookies.c */
extern __u32 syncookie_secret[2][16-4+SHA_DIGEST_WORDS];
@@ -472,7 +501,7 @@ static inline __u32 cookie_v6_init_sequence(struct sock *sk,
extern void __tcp_push_pending_frames(struct sock *sk, unsigned int cur_mss,
int nonagle);
-extern int tcp_may_send_now(struct sock *sk);
+extern bool tcp_may_send_now(struct sock *sk);
extern int tcp_retransmit_skb(struct sock *, struct sk_buff *);
extern void tcp_retransmit_timer(struct sock *sk);
extern void tcp_xmit_retransmit_queue(struct sock *);
@@ -486,15 +515,17 @@ extern int tcp_write_wakeup(struct sock *);
extern void tcp_send_fin(struct sock *sk);
extern void tcp_send_active_reset(struct sock *sk, gfp_t priority);
extern int tcp_send_synack(struct sock *);
-extern int tcp_syn_flood_action(struct sock *sk,
- const struct sk_buff *skb,
- const char *proto);
+extern bool tcp_syn_flood_action(struct sock *sk,
+ const struct sk_buff *skb,
+ const char *proto);
extern void tcp_push_one(struct sock *, unsigned int mss_now);
extern void tcp_send_ack(struct sock *sk);
extern void tcp_send_delayed_ack(struct sock *sk);
/* tcp_input.c */
extern void tcp_cwnd_application_limited(struct sock *sk);
+extern void tcp_resume_early_retransmit(struct sock *sk);
+extern void tcp_rearm_rto(struct sock *sk);
/* tcp_timer.c */
extern void tcp_init_xmit_timers(struct sock *);
@@ -540,8 +571,8 @@ extern int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
extern void tcp_initialize_rcv_mss(struct sock *sk);
-extern int tcp_mtu_to_mss(const struct sock *sk, int pmtu);
-extern int tcp_mss_to_mtu(const struct sock *sk, int mss);
+extern int tcp_mtu_to_mss(struct sock *sk, int pmtu);
+extern int tcp_mss_to_mtu(struct sock *sk, int mss);
extern void tcp_mtup_init(struct sock *sk);
extern void tcp_valid_rtt_meas(struct sock *sk, u32 seq_rtt);
@@ -556,6 +587,8 @@ static inline u32 __tcp_set_rto(const struct tcp_sock *tp)
return (tp->srtt >> 3) + tp->rttvar;
}
+extern void tcp_set_rto(struct sock *sk);
+
static inline void __tcp_fast_path_on(struct tcp_sock *tp, u32 snd_wnd)
{
tp->pred_flags = htonl((tp->tcp_header_len << 26) |
@@ -609,6 +642,8 @@ static inline u32 tcp_receive_window(const struct tcp_sock *tp)
*/
extern u32 __tcp_select_window(struct sock *sk);
+void tcp_send_window_probe(struct sock *sk);
+
/* TCP timestamps are only 32-bits, this causes a slight
* complication on 64-bit systems since we store a snapshot
* of jiffies in the buffer control blocks below. We decided
@@ -645,21 +680,38 @@ struct tcp_skb_cb {
__u32 end_seq; /* SEQ + FIN + SYN + datalen */
__u32 when; /* used to compute rtt's */
__u8 tcp_flags; /* TCP header flags. (tcp[13]) */
+
__u8 sacked; /* State flags for SACK/FACK. */
#define TCPCB_SACKED_ACKED 0x01 /* SKB ACK'd by a SACK block */
#define TCPCB_SACKED_RETRANS 0x02 /* SKB retransmitted */
#define TCPCB_LOST 0x04 /* SKB is lost */
#define TCPCB_TAGBITS 0x07 /* All tag bits */
- __u8 ip_dsfield; /* IPv4 tos or IPv6 dsfield */
- /* 1 byte hole */
#define TCPCB_EVER_RETRANS 0x80 /* Ever retransmitted frame */
#define TCPCB_RETRANS (TCPCB_SACKED_RETRANS|TCPCB_EVER_RETRANS)
+ __u8 ip_dsfield; /* IPv4 tos or IPv6 dsfield */
+ /* 1 byte hole */
__u32 ack_seq; /* Sequence number ACK'd */
};
#define TCP_SKB_CB(__skb) ((struct tcp_skb_cb *)&((__skb)->cb[0]))
+/* RFC3168 : 6.1.1 SYN packets must not have ECT/ECN bits set
+ *
+ * If we receive a SYN packet with these bits set, it means a network is
+ * playing bad games with TOS bits. In order to avoid possible false congestion
+ * notifications, we disable TCP ECN negociation.
+ */
+static inline void
+TCP_ECN_create_request(struct request_sock *req, const struct sk_buff *skb)
+{
+ const struct tcphdr *th = tcp_hdr(skb);
+
+ if (sysctl_tcp_ecn && th->ece && th->cwr &&
+ INET_ECN_is_not_ect(TCP_SKB_CB(skb)->ip_dsfield))
+ inet_rsk(req)->ecn_ok = 1;
+}
+
/* Due to TSO, an SKB can be composed of multiple actual
* packets. To keep these tracked properly, we use this.
*/
@@ -775,12 +827,12 @@ static inline int tcp_is_sack(const struct tcp_sock *tp)
return tp->rx_opt.sack_ok;
}
-static inline int tcp_is_reno(const struct tcp_sock *tp)
+static inline bool tcp_is_reno(const struct tcp_sock *tp)
{
return !tcp_is_sack(tp);
}
-static inline int tcp_is_fack(const struct tcp_sock *tp)
+static inline bool tcp_is_fack(const struct tcp_sock *tp)
{
return tp->rx_opt.sack_ok & TCP_FACK_ENABLED;
}
@@ -790,6 +842,21 @@ static inline void tcp_enable_fack(struct tcp_sock *tp)
tp->rx_opt.sack_ok |= TCP_FACK_ENABLED;
}
+/* TCP early-retransmit (ER) is similar to but more conservative than
+ * the thin-dupack feature. Enable ER only if thin-dupack is disabled.
+ */
+static inline void tcp_enable_early_retrans(struct tcp_sock *tp)
+{
+ tp->do_early_retrans = sysctl_tcp_early_retrans &&
+ !sysctl_tcp_thin_dupack && sysctl_tcp_reordering == 3;
+ tp->early_retrans_delayed = 0;
+}
+
+static inline void tcp_disable_early_retrans(struct tcp_sock *tp)
+{
+ tp->do_early_retrans = 0;
+}
+
static inline unsigned int tcp_left_out(const struct tcp_sock *tp)
{
return tp->sacked_out + tp->lost_out;
@@ -867,7 +934,7 @@ static inline u32 tcp_wnd_end(const struct tcp_sock *tp)
{
return tp->snd_una + tp->snd_wnd;
}
-extern int tcp_is_cwnd_limited(const struct sock *sk, u32 in_flight);
+extern bool tcp_is_cwnd_limited(const struct sock *sk, u32 in_flight);
static inline void tcp_minshall_update(struct tcp_sock *tp, unsigned int mss,
const struct sk_buff *skb)
@@ -910,7 +977,7 @@ static inline __sum16 __tcp_checksum_complete(struct sk_buff *skb)
return __skb_checksum_complete(skb);
}
-static inline int tcp_checksum_complete(struct sk_buff *skb)
+static inline bool tcp_checksum_complete(struct sk_buff *skb)
{
return !skb_csum_unnecessary(skb) &&
__tcp_checksum_complete(skb);
@@ -940,12 +1007,12 @@ static inline void tcp_prequeue_init(struct tcp_sock *tp)
*
* NOTE: is this not too big to inline?
*/
-static inline int tcp_prequeue(struct sock *sk, struct sk_buff *skb)
+static inline bool tcp_prequeue(struct sock *sk, struct sk_buff *skb)
{
struct tcp_sock *tp = tcp_sk(sk);
if (sysctl_tcp_low_latency || !tp->ucopy.task)
- return 0;
+ return false;
__skb_queue_tail(&tp->ucopy.prequeue, skb);
tp->ucopy.memory += skb->truesize;
@@ -969,7 +1036,7 @@ static inline int tcp_prequeue(struct sock *sk, struct sk_buff *skb)
(3 * tcp_rto_min(sk)) / 4,
TCP_RTO_MAX);
}
- return 1;
+ return true;
}
@@ -1074,28 +1141,28 @@ static inline int tcp_fin_time(const struct sock *sk)
return fin_timeout;
}
-static inline int tcp_paws_check(const struct tcp_options_received *rx_opt,
- int paws_win)
+static inline bool tcp_paws_check(const struct tcp_options_received *rx_opt,
+ int paws_win)
{
if ((s32)(rx_opt->ts_recent - rx_opt->rcv_tsval) <= paws_win)
- return 1;
+ return true;
if (unlikely(get_seconds() >= rx_opt->ts_recent_stamp + TCP_PAWS_24DAYS))
- return 1;
+ return true;
/*
* Some OSes send SYN and SYNACK messages with tsval=0 tsecr=0,
* then following tcp messages have valid values. Ignore 0 value,
* or else 'negative' tsval might forbid us to accept their packets.
*/
if (!rx_opt->ts_recent)
- return 1;
- return 0;
+ return true;
+ return false;
}
-static inline int tcp_paws_reject(const struct tcp_options_received *rx_opt,
- int rst)
+static inline bool tcp_paws_reject(const struct tcp_options_received *rx_opt,
+ int rst)
{
if (tcp_paws_check(rx_opt, 0))
- return 0;
+ return false;
/* RST segments are not recommended to carry timestamp,
and, if they do, it is recommended to ignore PAWS because
@@ -1110,8 +1177,8 @@ static inline int tcp_paws_reject(const struct tcp_options_received *rx_opt,
However, we can relax time bounds for RST segments to MSL.
*/
if (rst && get_seconds() >= rx_opt->ts_recent_stamp + TCP_PAWS_MSL)
- return 0;
- return 1;
+ return false;
+ return true;
}
static inline void tcp_mib_init(struct net *net)
@@ -1226,10 +1293,19 @@ extern void tcp_put_md5sig_pool(void);
extern int tcp_md5_hash_header(struct tcp_md5sig_pool *, const struct tcphdr *);
extern int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *, const struct sk_buff *,
- unsigned header_len);
+ unsigned int header_len);
extern int tcp_md5_hash_key(struct tcp_md5sig_pool *hp,
const struct tcp_md5sig_key *key);
+struct tcp_fastopen_request {
+ /* Fast Open cookie. Size 0 means a cookie request */
+ struct tcp_fastopen_cookie cookie;
+ struct msghdr *data; /* data in MSG_FASTOPEN */
+ u16 copied; /* queued in tcp_connect() */
+};
+
+void tcp_free_fastopen_req(struct tcp_sock *tp);
+
/* write queue abstraction */
static inline void tcp_write_queue_purge(struct sock *sk)
{
@@ -1349,7 +1425,7 @@ static inline void tcp_unlink_write_queue(struct sk_buff *skb, struct sock *sk)
__skb_unlink(skb, &sk->sk_write_queue);
}
-static inline int tcp_write_queue_empty(struct sock *sk)
+static inline bool tcp_write_queue_empty(struct sock *sk)
{
return skb_queue_empty(&sk->sk_write_queue);
}
@@ -1406,7 +1482,7 @@ static inline void tcp_highest_sack_combine(struct sock *sk,
/* Determines whether this is a thin stream (which may suffer from
* increased latency). Used to trigger latency-reducing mechanisms.
*/
-static inline unsigned int tcp_stream_is_thin(struct tcp_sock *tp)
+static inline bool tcp_stream_is_thin(struct tcp_sock *tp)
{
return tp->packets_out < 4 && !tcp_in_initial_slowstart(tp);
}
generated by cgit v1.2.3 (git 2.0.4) at 2025-09-14 16:32:35 +0000