1 files changed, 61 insertions, 32 deletions

diff --git a/include/linux/dccp.h b/include/linux/dccp.h
index 333c3ea82a5d..aa0737019e37 100644
--- a/include/linux/dccp.h
+++ b/include/linux/dccp.h
@@ -205,6 +205,7 @@ struct dccp_so_feat {
 #define DCCP_SOCKOPT_CHANGE_L           3
 #define DCCP_SOCKOPT_CHANGE_R           4
 #define DCCP_SOCKOPT_GET_CUR_MPS        5
+#define DCCP_SOCKOPT_SERVER_TIMEWAIT    6
 #define DCCP_SOCKOPT_SEND_CSCOV         10
 #define DCCP_SOCKOPT_RECV_CSCOV         11
 #define DCCP_SOCKOPT_CCID_RX_INFO       128
@@ -227,37 +228,50 @@ struct dccp_so_feat {
 #include <net/tcp_states.h>
 
 enum dccp_state {
-        DCCP_OPEN       = TCP_ESTABLISHED,
-        DCCP_REQUESTING = TCP_SYN_SENT,
-        DCCP_PARTOPEN   = TCP_FIN_WAIT1, /* FIXME:
-                                            This mapping is horrible, but TCP has
-                                            no matching state for DCCP_PARTOPEN,
-                                            as TCP_SYN_RECV is already used by
-                                            DCCP_RESPOND, why don't stop using TCP
-                                            mapping of states? OK, now we don't use
-                                            sk_stream_sendmsg anymore, so doesn't
-                                            seem to exist any reason for us to
-                                            do the TCP mapping here */
-        DCCP_LISTEN     = TCP_LISTEN,
-        DCCP_RESPOND    = TCP_SYN_RECV,
-        DCCP_CLOSING    = TCP_CLOSING,
-        DCCP_TIME_WAIT  = TCP_TIME_WAIT,
-        DCCP_CLOSED     = TCP_CLOSE,
-        DCCP_MAX_STATES = TCP_MAX_STATES,
+        DCCP_OPEN            = TCP_ESTABLISHED,
+        DCCP_REQUESTING      = TCP_SYN_SENT,
+        DCCP_LISTEN          = TCP_LISTEN,
+        DCCP_RESPOND         = TCP_SYN_RECV,
+        /*
+         * States involved in closing a DCCP connection:
+         * 1) ACTIVE_CLOSEREQ is entered by a server sending a CloseReq.
+         *
+         * 2) CLOSING can have three different meanings (RFC 4340, 8.3):
+         *  a. Client has performed active-close, has sent a Close to the server
+         *     from state OPEN or PARTOPEN, and is waiting for the final Reset
+         *     (in this case, SOCK_DONE == 1).
+         *  b. Client is asked to perform passive-close, by receiving a CloseReq
+         *     in (PART)OPEN state. It sends a Close and waits for final Reset
+         *     (in this case, SOCK_DONE == 0).
+         *  c. Server performs an active-close as in (a), keeps TIMEWAIT state.
+         *
+         * 3) The following intermediate states are employed to give passively
+         *    closing nodes a chance to process their unread data:
+         *    - PASSIVE_CLOSE    (from OPEN => CLOSED) and
+         *    - PASSIVE_CLOSEREQ (from (PART)OPEN to CLOSING; case (b) above).
+         */
+        DCCP_ACTIVE_CLOSEREQ = TCP_FIN_WAIT1,
+        DCCP_PASSIVE_CLOSE   = TCP_CLOSE_WAIT,  /* any node receiving a Close */
+        DCCP_CLOSING         = TCP_CLOSING,
+        DCCP_TIME_WAIT       = TCP_TIME_WAIT,
+        DCCP_CLOSED          = TCP_CLOSE,
+        DCCP_PARTOPEN        = TCP_MAX_STATES,
+        DCCP_PASSIVE_CLOSEREQ,                  /* clients receiving CloseReq */
+        DCCP_MAX_STATES
 };
 
-#define DCCP_STATE_MASK 0xf
-#define DCCP_ACTION_FIN (1<<7)
+#define DCCP_STATE_MASK 0x1f
 
 enum {
-        DCCPF_OPEN       = TCPF_ESTABLISHED,
-        DCCPF_REQUESTING = TCPF_SYN_SENT,
-        DCCPF_PARTOPEN   = TCPF_FIN_WAIT1,
-        DCCPF_LISTEN     = TCPF_LISTEN,
-        DCCPF_RESPOND    = TCPF_SYN_RECV,
-        DCCPF_CLOSING    = TCPF_CLOSING,
-        DCCPF_TIME_WAIT  = TCPF_TIME_WAIT,
-        DCCPF_CLOSED     = TCPF_CLOSE,
+        DCCPF_OPEN            = TCPF_ESTABLISHED,
+        DCCPF_REQUESTING      = TCPF_SYN_SENT,
+        DCCPF_LISTEN          = TCPF_LISTEN,
+        DCCPF_RESPOND         = TCPF_SYN_RECV,
+        DCCPF_ACTIVE_CLOSEREQ = TCPF_FIN_WAIT1,
+        DCCPF_CLOSING         = TCPF_CLOSING,
+        DCCPF_TIME_WAIT       = TCPF_TIME_WAIT,
+        DCCPF_CLOSED          = TCPF_CLOSE,
+        DCCPF_PARTOPEN        = (1 << DCCP_PARTOPEN),
 };
 
 static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb)
@@ -393,13 +407,23 @@ struct dccp_opt_pend {
 
 extern void dccp_minisock_init(struct dccp_minisock *dmsk);
 
-extern int dccp_parse_options(struct sock *sk, struct sk_buff *skb);
-
+/**
+ * struct dccp_request_sock  -  represent DCCP-specific connection request
+ * @dreq_inet_rsk: structure inherited from
+ * @dreq_iss: initial sequence number sent on the Response (RFC 4340, 7.1)
+ * @dreq_isr: initial sequence number received on the Request
+ * @dreq_service: service code present on the Request (there is just one)
+ * The following two fields are analogous to the ones in dccp_sock:
+ * @dreq_timestamp_echo: last received timestamp to echo (13.1)
+ * @dreq_timestamp_echo: the time of receiving the last @dreq_timestamp_echo
+ */
 struct dccp_request_sock {
         struct inet_request_sock dreq_inet_rsk;
         __u64                    dreq_iss;
         __u64                    dreq_isr;
         __be32                   dreq_service;
+        __u32                    dreq_timestamp_echo;
+        __u32                    dreq_timestamp_time;
 };
 
 static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
@@ -409,6 +433,9 @@ static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
 
 extern struct inet_timewait_death_row dccp_death_row;
 
+extern int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
+                              struct sk_buff *skb);
+
 struct dccp_options_received {
         u32     dccpor_ndp; /* only 24 bits */
         u32     dccpor_timestamp;
@@ -462,8 +489,8 @@ struct dccp_ackvec;
  * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss
  * @dccps_service - first (passive sock) or unique (active sock) service code
  * @dccps_service_list - second .. last service code on passive socket
- * @dccps_timestamp_time - time of latest TIMESTAMP option
  * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option
+ * @dccps_timestamp_time - time of receiving latest @dccps_timestamp_echo
  * @dccps_l_ack_ratio - feature-local Ack Ratio
  * @dccps_r_ack_ratio - feature-remote Ack Ratio
  * @dccps_pcslen - sender   partial checksum coverage (via sockopt)
@@ -479,6 +506,7 @@ struct dccp_ackvec;
  * @dccps_role - role of this sock, one of %dccp_role
  * @dccps_hc_rx_insert_options - receiver wants to add options when acking
  * @dccps_hc_tx_insert_options - sender wants to add options when sending
+ * @dccps_server_timewait - server holds timewait state on close (RFC 4340, 8.3)
  * @dccps_xmit_timer - timer for when CCID is not ready to send
  * @dccps_syn_rtt - RTT sample from Request/Response exchange (in usecs)
  */
@@ -497,15 +525,15 @@ struct dccp_sock {
         __u64                           dccps_gsr;
         __u64                           dccps_gar;
         __be32                          dccps_service;
+        __u32                           dccps_mss_cache;
         struct dccp_service_list        *dccps_service_list;
-        ktime_t                         dccps_timestamp_time;
         __u32                           dccps_timestamp_echo;
+        __u32                           dccps_timestamp_time;
         __u16                           dccps_l_ack_ratio;
         __u16                           dccps_r_ack_ratio;
         __u16                           dccps_pcslen;
         __u16                           dccps_pcrlen;
         unsigned long                   dccps_ndp_count;
-        __u32                           dccps_mss_cache;
         unsigned long                   dccps_rate_last;
         struct dccp_minisock            dccps_minisock;
         struct dccp_ackvec              *dccps_hc_rx_ackvec;
@@ -515,6 +543,7 @@ struct dccp_sock {
         enum dccp_role                  dccps_role:2;
         __u8                            dccps_hc_rx_insert_options:1;
         __u8                            dccps_hc_tx_insert_options:1;
+        __u8                            dccps_server_timewait:1;
         struct timer_list               dccps_xmit_timer;
 };