Merge branch 'dccp' of git://eden-feed.erg.abdn.ac.uk/dccp_exp

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / dccp / dccp.h

diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h
index c7370de4c4d5f43d0fb1940742d6d5a025faac04..5281190aa19ca4ac79c21e2ae21ee7fba9f04c58 100644 (file)
--- a/net/dccp/dccp.h
+++ b/net/dccp/dccp.h
@@ -86,10 +86,13 @@ extern void dccp_time_wait(struct sock *sk, int state, int timeo);
  */
 #define DCCP_RTO_MAX ((unsigned)(64 * HZ))
 
+/* DCCP base time resolution - 10 microseconds (RFC 4340, 13.1 ... 13.3) */
+#define DCCP_TIME_RESOLUTION   10
+
 /*
  * RTT sampling: sanity bounds and fallback RTT value from RFC 4340, section 3.4
  */
-#define DCCP_SANE_RTT_MIN      100
+#define DCCP_SANE_RTT_MIN      (10 * DCCP_TIME_RESOLUTION)
 #define DCCP_FALLBACK_RTT      (USEC_PER_SEC / 5)
 #define DCCP_SANE_RTT_MAX      (3 * USEC_PER_SEC)
 
@@ -234,8 +237,22 @@ extern void dccp_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
 extern void dccp_send_sync(struct sock *sk, const u64 seq,
                           const enum dccp_pkt_type pkt_type);
 
-extern void dccp_write_xmit(struct sock *sk, int block);
+/*
+ * TX Packet Dequeueing Interface
+ */
+extern void            dccp_qpolicy_push(struct sock *sk, struct sk_buff *skb);
+extern bool            dccp_qpolicy_full(struct sock *sk);
+extern void            dccp_qpolicy_drop(struct sock *sk, struct sk_buff *skb);
+extern struct sk_buff  *dccp_qpolicy_top(struct sock *sk);
+extern struct sk_buff  *dccp_qpolicy_pop(struct sock *sk);
+extern bool            dccp_qpolicy_param_ok(struct sock *sk, __be32 param);
+
+/*
+ * TX Packet Output and TX Timers
+ */
+extern void dccp_write_xmit(struct sock *sk);
 extern void dccp_write_space(struct sock *sk);
+extern void dccp_flush_write_queue(struct sock *sk, long *time_budget);
 
 extern void dccp_init_xmit_timers(struct sock *sk);
 static inline void dccp_clear_xmit_timers(struct sock *sk)
@@ -317,7 +334,14 @@ extern struct sk_buff *dccp_ctl_make_reset(struct sock *sk,
 extern int        dccp_send_reset(struct sock *sk, enum dccp_reset_codes code);
 extern void       dccp_send_close(struct sock *sk, const int active);
 extern int        dccp_invalid_packet(struct sk_buff *skb);
-extern u32        dccp_sample_rtt(struct sock *sk, long delta);
+
+static inline u32  dccp_sane_rtt(long usec_sample)
+{
+       if (unlikely(usec_sample <= 0 || usec_sample > DCCP_SANE_RTT_MAX))
+               DCCP_WARN("RTT sample %ld out of bounds!\n", usec_sample);
+       return clamp_val(usec_sample, DCCP_SANE_RTT_MIN, DCCP_SANE_RTT_MAX);
+}
+extern u32 dccp_sample_rtt(struct sock *sk, long delta);
 
 static inline int dccp_bad_service_code(const struct sock *sk,
                                        const __be32 service)
@@ -415,6 +439,23 @@ static inline void dccp_update_gsr(struct sock *sk, u64 seq)
        dp->dccps_gsr = seq;
        /* Sequence validity window depends on remote Sequence Window (7.5.1) */
        dp->dccps_swl = SUB48(ADD48(dp->dccps_gsr, 1), dp->dccps_r_seq_win / 4);
+       /*
+        * Adjust SWL so that it is not below ISR. In contrast to RFC 4340,
+        * 7.5.1 we perform this check beyond the initial handshake: W/W' are
+        * always > 32, so for the first W/W' packets in the lifetime of a
+        * connection we always have to adjust SWL.
+        * A second reason why we are doing this is that the window depends on
+        * the feature-remote value of Sequence Window: nothing stops the peer
+        * from updating this value while we are busy adjusting SWL for the
+        * first W packets (we would have to count from scratch again then).
+        * Therefore it is safer to always make sure that the Sequence Window
+        * is not artificially extended by a peer who grows SWL downwards by
+        * continually updating the feature-remote Sequence-Window.
+        * If sequence numbers wrap it is bad luck. But that will take a while
+        * (48 bit), and this measure prevents Sequence-number attacks.
+        */
+       if (before48(dp->dccps_swl, dp->dccps_isr))
+               dp->dccps_swl = dp->dccps_isr;
        dp->dccps_swh = ADD48(dp->dccps_gsr, (3 * dp->dccps_r_seq_win) / 4);
 }
 
@@ -425,18 +466,21 @@ static inline void dccp_update_gss(struct sock *sk, u64 seq)
        dp->dccps_gss = seq;
        /* Ack validity window depends on local Sequence Window value (7.5.1) */
        dp->dccps_awl = SUB48(ADD48(dp->dccps_gss, 1), dp->dccps_l_seq_win);
+       /* Adjust AWL so that it is not below ISS - see comment above for SWL */
+       if (before48(dp->dccps_awl, dp->dccps_iss))
+               dp->dccps_awl = dp->dccps_iss;
        dp->dccps_awh = dp->dccps_gss;
 }
 
+static inline int dccp_ackvec_pending(const struct sock *sk)
+{
+       return dccp_sk(sk)->dccps_hc_rx_ackvec != NULL &&
+              !dccp_ackvec_is_empty(dccp_sk(sk)->dccps_hc_rx_ackvec);
+}
+
 static inline int dccp_ack_pending(const struct sock *sk)
 {
-       const struct dccp_sock *dp = dccp_sk(sk);
-       return dp->dccps_timestamp_echo != 0 ||
-#ifdef CONFIG_IP_DCCP_ACKVEC
-              (dp->dccps_hc_rx_ackvec != NULL &&
-               dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) ||
-#endif
-              inet_csk_ack_scheduled(sk);
+       return dccp_ackvec_pending(sk) || inet_csk_ack_scheduled(sk);
 }
 
 extern int  dccp_feat_signal_nn_change(struct sock *sk, u8 feat, u64 nn_val);