#include <linux/dmaengine.h>
#include <linux/crypto.h>
#include <linux/cryptohash.h>
+#include <linux/kref.h>
#include <net/inet_connection_sock.h>
#include <net/inet_timewait_sock.h>
#define TCPOPT_SACK 5 /* SACK Block */
#define TCPOPT_TIMESTAMP 8 /* Better RTT estimations/PAWS */
#define TCPOPT_MD5SIG 19 /* MD5 Signature (RFC2385) */
+#define TCPOPT_COOKIE 253 /* Cookie extension (experimental) */
/*
* TCP option lengths
#define TCPOLEN_SACK_PERM 2
#define TCPOLEN_TIMESTAMP 10
#define TCPOLEN_MD5SIG 18
+#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)
+#define TCPOLEN_COOKIE_MAX (TCPOLEN_COOKIE_BASE+TCP_COOKIE_MAX)
/* But this is what stacks really send out. */
#define TCPOLEN_TSTAMP_ALIGNED 12
#define TCP_NAGLE_CORK 2 /* Socket is corked */
#define TCP_NAGLE_PUSH 4 /* Cork is overridden for already queued data */
+/* TCP thin-stream limits */
+#define TCP_THIN_LINEAR_RETRIES 6 /* After 6 linear retries, do exp. backoff */
+
extern struct inet_timewait_death_row tcp_death_row;
/* sysctl variables for tcp */
extern int sysctl_tcp_workaround_signed_windows;
extern int sysctl_tcp_slow_start_after_idle;
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 atomic_t tcp_memory_allocated;
extern struct percpu_counter tcp_sockets_allocated;
#define TCP_INC_STATS_BH(net, field) SNMP_INC_STATS_BH((net)->mib.tcp_statistics, field)
#define TCP_DEC_STATS(net, field) SNMP_DEC_STATS((net)->mib.tcp_statistics, field)
#define TCP_ADD_STATS_USER(net, field, val) SNMP_ADD_STATS_USER((net)->mib.tcp_statistics, field, val)
+#define TCP_ADD_STATS(net, field, val) SNMP_ADD_STATS((net)->mib.tcp_statistics, field, val)
extern void tcp_v4_err(struct sk_buff *skb, u32);
extern void tcp_enter_quickack_mode(struct sock *sk);
-static inline void tcp_clear_options(struct tcp_options_received *rx_opt)
-{
- rx_opt->tstamp_ok = rx_opt->sack_ok = rx_opt->wscale_ok = rx_opt->snd_wscale = 0;
-}
-
#define TCP_ECN_OK 1
#define TCP_ECN_QUEUE_CWR 2
#define TCP_ECN_DEMAND_CWR 4
int level, int optname,
char __user *optval, unsigned int optlen);
extern void tcp_set_keepalive(struct sock *sk, int val);
+extern void tcp_syn_ack_timeout(struct sock *sk,
+ struct request_sock *req);
extern int tcp_recvmsg(struct kiocb *iocb, struct sock *sk,
struct msghdr *msg,
size_t len, int nonblock,
extern void tcp_parse_options(struct sk_buff *skb,
struct tcp_options_received *opt_rx,
- int estab,
- struct dst_entry *dst);
+ u8 **hvpp,
+ int estab);
extern u8 *tcp_parse_md5sig_option(struct tcphdr *th);
* TCP v4 functions exported for the inet6 API
*/
-extern void tcp_v4_send_check(struct sock *sk, int len,
+extern void tcp_v4_send_check(struct sock *sk,
struct sk_buff *skb);
extern int tcp_v4_conn_request(struct sock *sk,
icsk->icsk_rto, TCP_RTO_MAX);
}
-static inline void tcp_push_pending_frames(struct sock *sk)
-{
- struct tcp_sock *tp = tcp_sk(sk);
-
- __tcp_push_pending_frames(sk, tcp_current_mss(sk), tp->nonagle);
-}
-
static inline void tcp_init_wl(struct tcp_sock *tp, u32 seq)
{
tp->snd_wl1 = seq;
tp->ucopy.memory = 0;
} else if (skb_queue_len(&tp->ucopy.prequeue) == 1) {
- wake_up_interruptible_poll(sk->sk_sleep,
+ wake_up_interruptible_sync_poll(sk_sleep(sk),
POLLIN | POLLRDNORM | POLLRDBAND);
if (!inet_csk_ack_scheduled(sk))
inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
/* Determine a window scaling and initial window to offer. */
extern void tcp_select_initial_window(int __space, __u32 mss,
__u32 *rcv_wnd, __u32 *window_clamp,
- int wscale_ok, __u8 *rcv_wscale);
+ int wscale_ok, __u8 *rcv_wscale,
+ __u32 init_rcv_wnd);
static inline int tcp_win_from_space(int space)
{
return tp->keepalive_probes ? : sysctl_tcp_keepalive_probes;
}
+static inline u32 keepalive_time_elapsed(const struct tcp_sock *tp)
+{
+ const struct inet_connection_sock *icsk = &tp->inet_conn;
+
+ return min_t(u32, tcp_time_stamp - icsk->icsk_ack.lrcvtime,
+ tcp_time_stamp - tp->rcv_tstamp);
+}
+
static inline int tcp_fin_time(const struct sock *sk)
{
int fin_timeout = tcp_sk(sk)->linger2 ? : sysctl_tcp_fin_timeout;
#define tcp_twsk_md5_key(twsk) NULL
#endif
-extern struct tcp_md5sig_pool **tcp_alloc_md5sig_pool(struct sock *);
+extern struct tcp_md5sig_pool * __percpu *tcp_alloc_md5sig_pool(struct sock *);
extern void tcp_free_md5sig_pool(void);
-extern struct tcp_md5sig_pool *__tcp_get_md5sig_pool(int cpu);
-extern void __tcp_put_md5sig_pool(void);
+extern struct tcp_md5sig_pool *tcp_get_md5sig_pool(void);
+extern void tcp_put_md5sig_pool(void);
+
extern int tcp_md5_hash_header(struct tcp_md5sig_pool *, struct tcphdr *);
extern int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *, struct sk_buff *,
unsigned header_len);
extern int tcp_md5_hash_key(struct tcp_md5sig_pool *hp,
struct tcp_md5sig_key *key);
-static inline
-struct tcp_md5sig_pool *tcp_get_md5sig_pool(void)
-{
- int cpu = get_cpu();
- struct tcp_md5sig_pool *ret = __tcp_get_md5sig_pool(cpu);
- if (!ret)
- put_cpu();
- return ret;
-}
-
-static inline void tcp_put_md5sig_pool(void)
-{
- __tcp_put_md5sig_pool();
- put_cpu();
-}
-
/* write queue abstraction */
static inline void tcp_write_queue_purge(struct sock *sk)
{
while ((skb = __skb_dequeue(&sk->sk_write_queue)) != NULL)
sk_wmem_free_skb(sk, skb);
sk_mem_reclaim(sk);
+ tcp_clear_all_retrans_hints(tcp_sk(sk));
}
static inline struct sk_buff *tcp_write_queue_head(struct sock *sk)
#define tcp_for_write_queue_from_safe(skb, tmp, sk) \
skb_queue_walk_from_safe(&(sk)->sk_write_queue, skb, tmp)
-/* This function calculates a "timeout" which is equivalent to the timeout of a
- * TCP connection after "boundary" unsucessful, exponentially backed-off
- * retransmissions with an initial RTO of TCP_RTO_MIN.
- */
-static inline bool retransmits_timed_out(const struct sock *sk,
- unsigned int boundary)
-{
- unsigned int timeout, linear_backoff_thresh;
-
- if (!inet_csk(sk)->icsk_retransmits)
- return false;
-
- linear_backoff_thresh = ilog2(TCP_RTO_MAX/TCP_RTO_MIN);
-
- if (boundary <= linear_backoff_thresh)
- timeout = ((2 << boundary) - 1) * TCP_RTO_MIN;
- else
- timeout = ((2 << linear_backoff_thresh) - 1) * TCP_RTO_MIN +
- (boundary - linear_backoff_thresh) * TCP_RTO_MAX;
-
- return (tcp_time_stamp - tcp_sk(sk)->retrans_stamp) >= timeout;
-}
-
static inline struct sk_buff *tcp_send_head(struct sock *sk)
{
return sk->sk_send_head;
return skb_queue_empty(&sk->sk_write_queue);
}
+static inline void tcp_push_pending_frames(struct sock *sk)
+{
+ if (tcp_send_head(sk)) {
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ __tcp_push_pending_frames(sk, tcp_current_mss(sk), tp->nonagle);
+ }
+}
+
/* Start sequence of the highest skb with SACKed bit, valid only if
* sacked > 0 or when the caller has ensured validity by itself.
*/
tcp_sk(sk)->highest_sack = new;
}
+/* 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)
+{
+ return tp->packets_out < 4 && !tcp_in_initial_slowstart(tp);
+}
+
/* /proc */
enum tcp_seq_states {
TCP_SEQ_STATE_LISTENING,
extern int tcp_cookie_generator(u32 *bakery);
+/**
+ * struct tcp_cookie_values - each socket needs extra space for the
+ * cookies, together with (optional) space for any SYN data.
+ *
+ * A tcp_sock contains a pointer to the current value, and this is
+ * cloned to the tcp_timewait_sock.
+ *
+ * @cookie_pair: variable data from the option exchange.
+ *
+ * @cookie_desired: user specified tcpct_cookie_desired. Zero
+ * indicates default (sysctl_tcp_cookie_size).
+ * After cookie sent, remembers size of cookie.
+ * Range 0, TCP_COOKIE_MIN to TCP_COOKIE_MAX.
+ *
+ * @s_data_desired: user specified tcpct_s_data_desired. When the
+ * constant payload is specified (@s_data_constant),
+ * holds its length instead.
+ * Range 0 to TCP_MSS_DESIRED.
+ *
+ * @s_data_payload: constant data that is to be included in the
+ * payload of SYN or SYNACK segments when the
+ * cookie option is present.
+ */
+struct tcp_cookie_values {
+ struct kref kref;
+ u8 cookie_pair[TCP_COOKIE_PAIR_SIZE];
+ u8 cookie_pair_size;
+ u8 cookie_desired;
+ u16 s_data_desired:11,
+ s_data_constant:1,
+ s_data_in:1,
+ s_data_out:1,
+ s_data_unused:2;
+ u8 s_data_payload[0];
+};
+
+static inline void tcp_cookie_values_release(struct kref *kref)
+{
+ kfree(container_of(kref, struct tcp_cookie_values, kref));
+}
+
+/* The length of constant payload data. Note that s_data_desired is
+ * overloaded, depending on s_data_constant: either the length of constant
+ * data (returned here) or the limit on variable data.
+ */
+static inline int tcp_s_data_size(const struct tcp_sock *tp)
+{
+ return (tp->cookie_values != NULL && tp->cookie_values->s_data_constant)
+ ? tp->cookie_values->s_data_desired
+ : 0;
+}
+
+/**
+ * struct tcp_extend_values - tcp_ipv?.c to tcp_output.c workspace.
+ *
+ * As tcp_request_sock has already been extended in other places, the
+ * only remaining method is to pass stack values along as function
+ * parameters. These parameters are not needed after sending SYNACK.
+ *
+ * @cookie_bakery: cryptographic secret and message workspace.
+ *
+ * @cookie_plus: bytes in authenticator/cookie option, copied from
+ * struct tcp_options_received (above).
+ */
+struct tcp_extend_values {
+ struct request_values rv;
+ u32 cookie_bakery[COOKIE_WORKSPACE_WORDS];
+ u8 cookie_plus:6,
+ cookie_out_never:1,
+ cookie_in_always:1;
+};
+
+static inline struct tcp_extend_values *tcp_xv(struct request_values *rvp)
+{
+ return (struct tcp_extend_values *)rvp;
+}
+
extern void tcp_v4_init(void);
extern void tcp_init(void);